diff options
| author | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2015-08-05 17:04:01 -0300 |
|---|---|---|
| committer | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2015-08-05 17:04:01 -0300 |
| commit | 57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch) | |
| tree | 5e910f0e82173f4ef4f51111366a3f1299037a7b /drivers/spi | |
Initial import
Diffstat (limited to 'drivers/spi')
89 files changed, 56934 insertions, 0 deletions
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig new file mode 100644 index 000000000..72b059081 --- /dev/null +++ b/drivers/spi/Kconfig @@ -0,0 +1,672 @@ +# +# SPI driver configuration +# +# NOTE: the reason this doesn't show SPI slave support is mostly that +# nobody's needed a slave side API yet. The master-role API is not +# fully appropriate there, so it'd need some thought to do well. +# +menuconfig SPI + bool "SPI support" + depends on HAS_IOMEM + help + The "Serial Peripheral Interface" is a low level synchronous + protocol. Chips that support SPI can have data transfer rates + up to several tens of Mbit/sec. Chips are addressed with a + controller and a chipselect. Most SPI slaves don't support + dynamic device discovery; some are even write-only or read-only. + + SPI is widely used by microcontrollers to talk with sensors, + eeprom and flash memory, codecs and various other controller + chips, analog to digital (and d-to-a) converters, and more. + MMC and SD cards can be accessed using SPI protocol; and for + DataFlash cards used in MMC sockets, SPI must always be used. + + SPI is one of a family of similar protocols using a four wire + interface (select, clock, data in, data out) including Microwire + (half duplex), SSP, SSI, and PSP. This driver framework should + work with most such devices and controllers. + +if SPI + +config SPI_DEBUG + bool "Debug support for SPI drivers" + depends on DEBUG_KERNEL + help + Say "yes" to enable debug messaging (like dev_dbg and pr_debug), + sysfs, and debugfs support in SPI controller and protocol drivers. + +# +# MASTER side ... talking to discrete SPI slave chips including microcontrollers +# + +config SPI_MASTER +# bool "SPI Master Support" + bool + default SPI + help + If your system has an master-capable SPI controller (which + provides the clock and chipselect), you can enable that + controller and the protocol drivers for the SPI slave chips + that are connected. + +if SPI_MASTER + +comment "SPI Master Controller Drivers" + +config SPI_ALTERA + tristate "Altera SPI Controller" + select SPI_BITBANG + help + This is the driver for the Altera SPI Controller. + +config SPI_ATH79 + tristate "Atheros AR71XX/AR724X/AR913X SPI controller driver" + depends on ATH79 && GPIOLIB + select SPI_BITBANG + help + This enables support for the SPI controller present on the + Atheros AR71XX/AR724X/AR913X SoCs. + +config SPI_ATMEL + tristate "Atmel SPI Controller" + depends on HAS_DMA + depends on (ARCH_AT91 || AVR32 || COMPILE_TEST) + help + This selects a driver for the Atmel SPI Controller, present on + many AT32 (AVR32) and AT91 (ARM) chips. + +config SPI_BCM2835 + tristate "BCM2835 SPI controller" + depends on ARCH_BCM2835 || COMPILE_TEST + depends on GPIOLIB + help + This selects a driver for the Broadcom BCM2835 SPI master. + + The BCM2835 contains two types of SPI master controller; the + "universal SPI master", and the regular SPI controller. This driver + is for the regular SPI controller. Slave mode operation is not also + not supported. + +config SPI_BFIN5XX + tristate "SPI controller driver for ADI Blackfin5xx" + depends on BLACKFIN && !BF60x + help + This is the SPI controller master driver for Blackfin 5xx processor. + +config SPI_ADI_V3 + tristate "SPI controller v3 for ADI" + depends on BF60x + help + This is the SPI controller v3 master driver + found on Blackfin 60x processor. + +config SPI_BFIN_SPORT + tristate "SPI bus via Blackfin SPORT" + depends on BLACKFIN + help + Enable support for a SPI bus via the Blackfin SPORT peripheral. + +config SPI_AU1550 + tristate "Au1550/Au1200/Au1300 SPI Controller" + depends on MIPS_ALCHEMY + select SPI_BITBANG + help + If you say yes to this option, support will be included for the + PSC SPI controller found on Au1550, Au1200 and Au1300 series. + +config SPI_BCM53XX + tristate "Broadcom BCM53xx SPI controller" + depends on ARCH_BCM_5301X + depends on BCMA_POSSIBLE + select BCMA + help + Enable support for the SPI controller on Broadcom BCM53xx ARM SoCs. + +config SPI_BCM63XX + tristate "Broadcom BCM63xx SPI controller" + depends on BCM63XX + help + Enable support for the SPI controller on the Broadcom BCM63xx SoCs. + +config SPI_BCM63XX_HSSPI + tristate "Broadcom BCM63XX HS SPI controller driver" + depends on BCM63XX || COMPILE_TEST + help + This enables support for the High Speed SPI controller present on + newer Broadcom BCM63XX SoCs. + +config SPI_BITBANG + tristate "Utilities for Bitbanging SPI masters" + help + With a few GPIO pins, your system can bitbang the SPI protocol. + Select this to get SPI support through I/O pins (GPIO, parallel + port, etc). Or, some systems' SPI master controller drivers use + this code to manage the per-word or per-transfer accesses to the + hardware shift registers. + + This is library code, and is automatically selected by drivers that + need it. You only need to select this explicitly to support driver + modules that aren't part of this kernel tree. + +config SPI_BUTTERFLY + tristate "Parallel port adapter for AVR Butterfly (DEVELOPMENT)" + depends on PARPORT + select SPI_BITBANG + help + This uses a custom parallel port cable to connect to an AVR + Butterfly <http://www.atmel.com/products/avr/butterfly>, an + inexpensive battery powered microcontroller evaluation board. + This same cable can be used to flash new firmware. + +config SPI_CADENCE + tristate "Cadence SPI controller" + help + This selects the Cadence SPI controller master driver + used by Xilinx Zynq and ZynqMP. + +config SPI_CLPS711X + tristate "CLPS711X host SPI controller" + depends on ARCH_CLPS711X || COMPILE_TEST + help + This enables dedicated general purpose SPI/Microwire1-compatible + master mode interface (SSI1) for CLPS711X-based CPUs. + +config SPI_COLDFIRE_QSPI + tristate "Freescale Coldfire QSPI controller" + depends on (M520x || M523x || M5249 || M525x || M527x || M528x || M532x) + help + This enables support for the Coldfire QSPI controller in master + mode. + +config SPI_DAVINCI + tristate "Texas Instruments DaVinci/DA8x/OMAP-L/AM1x SoC SPI controller" + depends on ARCH_DAVINCI || ARCH_KEYSTONE + select SPI_BITBANG + help + SPI master controller for DaVinci/DA8x/OMAP-L/AM1x SPI modules. + +config SPI_DLN2 + tristate "Diolan DLN-2 USB SPI adapter" + depends on MFD_DLN2 + help + If you say yes to this option, support will be included for Diolan + DLN2, a USB to SPI interface. + + This driver can also be built as a module. If so, the module + will be called spi-dln2. + +config SPI_EFM32 + tristate "EFM32 SPI controller" + depends on OF && ARM && (ARCH_EFM32 || COMPILE_TEST) + select SPI_BITBANG + help + Driver for the spi controller found on Energy Micro's EFM32 SoCs. + +config SPI_EP93XX + tristate "Cirrus Logic EP93xx SPI controller" + depends on HAS_DMA + depends on ARCH_EP93XX || COMPILE_TEST + help + This enables using the Cirrus EP93xx SPI controller in master + mode. + +config SPI_FALCON + tristate "Falcon SPI controller support" + depends on SOC_FALCON + help + The external bus unit (EBU) found on the FALC-ON SoC has SPI + emulation that is designed for serial flash access. This driver + has only been tested with m25p80 type chips. The hardware has no + support for other types of SPI peripherals. + +config SPI_GPIO + tristate "GPIO-based bitbanging SPI Master" + depends on GPIOLIB + select SPI_BITBANG + help + This simple GPIO bitbanging SPI master uses the arch-neutral GPIO + interface to manage MOSI, MISO, SCK, and chipselect signals. SPI + slaves connected to a bus using this driver are configured as usual, + except that the spi_board_info.controller_data holds the GPIO number + for the chipselect used by this controller driver. + + Note that this driver often won't achieve even 1 Mbit/sec speeds, + making it unusually slow for SPI. If your platform can inline + GPIO operations, you should be able to leverage that for better + speed with a custom version of this driver; see the source code. + +config SPI_IMG_SPFI + tristate "IMG SPFI controller" + depends on MIPS || COMPILE_TEST + help + This enables support for the SPFI master controller found on + IMG SoCs. + +config SPI_IMX + tristate "Freescale i.MX SPI controllers" + depends on ARCH_MXC || COMPILE_TEST + select SPI_BITBANG + help + This enables using the Freescale i.MX SPI controllers in master + mode. + +config SPI_LM70_LLP + tristate "Parallel port adapter for LM70 eval board (DEVELOPMENT)" + depends on PARPORT + select SPI_BITBANG + help + This driver supports the NS LM70 LLP Evaluation Board, + which interfaces to an LM70 temperature sensor using + a parallel port. + +config SPI_MPC52xx + tristate "Freescale MPC52xx SPI (non-PSC) controller support" + depends on PPC_MPC52xx + help + This drivers supports the MPC52xx SPI controller in master SPI + mode. + +config SPI_MPC52xx_PSC + tristate "Freescale MPC52xx PSC SPI controller" + depends on PPC_MPC52xx + help + This enables using the Freescale MPC52xx Programmable Serial + Controller in master SPI mode. + +config SPI_MPC512x_PSC + tristate "Freescale MPC512x PSC SPI controller" + depends on PPC_MPC512x + help + This enables using the Freescale MPC5121 Programmable Serial + Controller in SPI master mode. + +config SPI_FSL_LIB + tristate + depends on OF + +config SPI_FSL_CPM + tristate + depends on FSL_SOC + +config SPI_FSL_SPI + tristate "Freescale SPI controller and Aeroflex Gaisler GRLIB SPI controller" + depends on OF + select SPI_FSL_LIB + select SPI_FSL_CPM if FSL_SOC + help + This enables using the Freescale SPI controllers in master mode. + MPC83xx platform uses the controller in cpu mode or CPM/QE mode. + MPC8569 uses the controller in QE mode, MPC8610 in cpu mode. + This also enables using the Aeroflex Gaisler GRLIB SPI controller in + master mode. + +config SPI_FSL_DSPI + tristate "Freescale DSPI controller" + select REGMAP_MMIO + depends on SOC_VF610 || SOC_LS1021A || COMPILE_TEST + help + This enables support for the Freescale DSPI controller in master + mode. VF610 platform uses the controller. + +config SPI_FSL_ESPI + tristate "Freescale eSPI controller" + depends on FSL_SOC + select SPI_FSL_LIB + help + This enables using the Freescale eSPI controllers in master mode. + From MPC8536, 85xx platform uses the controller, and all P10xx, + P20xx, P30xx,P40xx, P50xx uses this controller. + +config SPI_MESON_SPIFC + tristate "Amlogic Meson SPIFC controller" + depends on ARCH_MESON || COMPILE_TEST + select REGMAP_MMIO + help + This enables master mode support for the SPIFC (SPI flash + controller) available in Amlogic Meson SoCs. + +config SPI_OC_TINY + tristate "OpenCores tiny SPI" + depends on GPIOLIB + select SPI_BITBANG + help + This is the driver for OpenCores tiny SPI master controller. + +config SPI_OCTEON + tristate "Cavium OCTEON SPI controller" + depends on CAVIUM_OCTEON_SOC + help + SPI host driver for the hardware found on some Cavium OCTEON + SOCs. + +config SPI_OMAP_UWIRE + tristate "OMAP1 MicroWire" + depends on ARCH_OMAP1 + select SPI_BITBANG + help + This hooks up to the MicroWire controller on OMAP1 chips. + +config SPI_OMAP24XX + tristate "McSPI driver for OMAP" + depends on HAS_DMA + depends on ARM || ARM64 || AVR32 || HEXAGON || MIPS || SUPERH + depends on ARCH_OMAP2PLUS || COMPILE_TEST + help + SPI master controller for OMAP24XX and later Multichannel SPI + (McSPI) modules. + +config SPI_TI_QSPI + tristate "DRA7xxx QSPI controller support" + depends on ARCH_OMAP2PLUS || COMPILE_TEST + help + QSPI master controller for DRA7xxx used for flash devices. + This device supports single, dual and quad read support, while + it only supports single write mode. + +config SPI_OMAP_100K + tristate "OMAP SPI 100K" + depends on ARCH_OMAP850 || ARCH_OMAP730 || COMPILE_TEST + help + OMAP SPI 100K master controller for omap7xx boards. + +config SPI_ORION + tristate "Orion SPI master" + depends on PLAT_ORION || COMPILE_TEST + help + This enables using the SPI master controller on the Orion chips. + +config SPI_PL022 + tristate "ARM AMBA PL022 SSP controller" + depends on ARM_AMBA + default y if MACH_U300 + default y if ARCH_REALVIEW + default y if INTEGRATOR_IMPD1 + default y if ARCH_VERSATILE + help + This selects the ARM(R) AMBA(R) PrimeCell PL022 SSP + controller. If you have an embedded system with an AMBA(R) + bus and a PL022 controller, say Y or M here. + +config SPI_PPC4xx + tristate "PPC4xx SPI Controller" + depends on PPC32 && 4xx + select SPI_BITBANG + help + This selects a driver for the PPC4xx SPI Controller. + +config SPI_PXA2XX_PXADMA + bool "PXA2xx SSP legacy PXA DMA API support" + depends on SPI_PXA2XX && ARCH_PXA + help + Enable PXA private legacy DMA API support. Note that this is + deprecated in favor of generic DMA engine API. + +config SPI_PXA2XX_DMA + def_bool y + depends on SPI_PXA2XX && !SPI_PXA2XX_PXADMA + +config SPI_PXA2XX + tristate "PXA2xx SSP SPI master" + depends on (ARCH_PXA || PCI || ACPI) + select PXA_SSP if ARCH_PXA + help + This enables using a PXA2xx or Sodaville SSP port as a SPI master + controller. The driver can be configured to use any SSP port and + additional documentation can be found a Documentation/spi/pxa2xx. + +config SPI_PXA2XX_PCI + def_tristate SPI_PXA2XX && PCI && COMMON_CLK + +config SPI_ROCKCHIP + tristate "Rockchip SPI controller driver" + depends on ARM || ARM64 || AVR32 || HEXAGON || MIPS || SUPERH + help + This selects a driver for Rockchip SPI controller. + + If you say yes to this option, support will be included for + RK3066, RK3188 and RK3288 families of SPI controller. + Rockchip SPI controller support DMA transport and PIO mode. + The main usecase of this controller is to use spi flash as boot + device. + +config SPI_RSPI + tristate "Renesas RSPI/QSPI controller" + depends on SUPERH || ARCH_SHMOBILE || COMPILE_TEST + help + SPI driver for Renesas RSPI and QSPI blocks. + +config SPI_QUP + tristate "Qualcomm SPI controller with QUP interface" + depends on ARCH_QCOM || (ARM && COMPILE_TEST) + help + Qualcomm Universal Peripheral (QUP) core is an AHB slave that + provides a common data path (an output FIFO and an input FIFO) + for serial peripheral interface (SPI) mini-core. SPI in master + mode supports up to 50MHz, up to four chip selects, programmable + data path from 4 bits to 32 bits and numerous protocol variants. + + This driver can also be built as a module. If so, the module + will be called spi_qup. + +config SPI_S3C24XX + tristate "Samsung S3C24XX series SPI" + depends on ARCH_S3C24XX + select SPI_BITBANG + help + SPI driver for Samsung S3C24XX series ARM SoCs + +config SPI_S3C24XX_FIQ + bool "S3C24XX driver with FIQ pseudo-DMA" + depends on SPI_S3C24XX + select FIQ + help + Enable FIQ support for the S3C24XX SPI driver to provide pseudo + DMA by using the fast-interrupt request framework, This allows + the driver to get DMA-like performance when there are either + no free DMA channels, or when doing transfers that required both + TX and RX data paths. + +config SPI_S3C64XX + tristate "Samsung S3C64XX series type SPI" + depends on (PLAT_SAMSUNG || ARCH_EXYNOS) + help + SPI driver for Samsung S3C64XX and newer SoCs. + +config SPI_SC18IS602 + tristate "NXP SC18IS602/602B/603 I2C to SPI bridge" + depends on I2C + help + SPI driver for NXP SC18IS602/602B/603 I2C to SPI bridge. + +config SPI_SH_MSIOF + tristate "SuperH MSIOF SPI controller" + depends on HAVE_CLK && HAS_DMA + depends on SUPERH || ARCH_SHMOBILE || COMPILE_TEST + help + SPI driver for SuperH and SH Mobile MSIOF blocks. + +config SPI_SH + tristate "SuperH SPI controller" + depends on SUPERH || COMPILE_TEST + help + SPI driver for SuperH SPI blocks. + +config SPI_SH_SCI + tristate "SuperH SCI SPI controller" + depends on SUPERH + select SPI_BITBANG + help + SPI driver for SuperH SCI blocks. + +config SPI_SH_HSPI + tristate "SuperH HSPI controller" + depends on ARCH_SHMOBILE || COMPILE_TEST + help + SPI driver for SuperH HSPI blocks. + +config SPI_SIRF + tristate "CSR SiRFprimaII SPI controller" + depends on SIRF_DMA + select SPI_BITBANG + help + SPI driver for CSR SiRFprimaII SoCs + +config SPI_ST_SSC4 + tristate "STMicroelectronics SPI SSC-based driver" + depends on ARCH_STI + help + STMicroelectronics SoCs support for SPI. If you say yes to + this option, support will be included for the SSC driven SPI. + +config SPI_SUN4I + tristate "Allwinner A10 SoCs SPI controller" + depends on ARCH_SUNXI || COMPILE_TEST + help + SPI driver for Allwinner sun4i, sun5i and sun7i SoCs + +config SPI_SUN6I + tristate "Allwinner A31 SPI controller" + depends on ARCH_SUNXI || COMPILE_TEST + depends on RESET_CONTROLLER + help + This enables using the SPI controller on the Allwinner A31 SoCs. + +config SPI_MXS + tristate "Freescale MXS SPI controller" + depends on ARCH_MXS + select STMP_DEVICE + help + SPI driver for Freescale MXS devices. + +config SPI_TEGRA114 + tristate "NVIDIA Tegra114 SPI Controller" + depends on (ARCH_TEGRA && TEGRA20_APB_DMA) || COMPILE_TEST + depends on RESET_CONTROLLER && HAS_DMA + help + SPI driver for NVIDIA Tegra114 SPI Controller interface. This controller + is different than the older SoCs SPI controller and also register interface + get changed with this controller. + +config SPI_TEGRA20_SFLASH + tristate "Nvidia Tegra20 Serial flash Controller" + depends on ARCH_TEGRA || COMPILE_TEST + depends on RESET_CONTROLLER + help + SPI driver for Nvidia Tegra20 Serial flash Controller interface. + The main usecase of this controller is to use spi flash as boot + device. + +config SPI_TEGRA20_SLINK + tristate "Nvidia Tegra20/Tegra30 SLINK Controller" + depends on (ARCH_TEGRA && TEGRA20_APB_DMA) || COMPILE_TEST + depends on RESET_CONTROLLER && HAS_DMA + help + SPI driver for Nvidia Tegra20/Tegra30 SLINK Controller interface. + +config SPI_TOPCLIFF_PCH + tristate "Intel EG20T PCH/LAPIS Semicon IOH(ML7213/ML7223/ML7831) SPI" + depends on PCI && (X86_32 || COMPILE_TEST) + help + SPI driver for the Topcliff PCH (Platform Controller Hub) SPI bus + used in some x86 embedded processors. + + This driver also supports the ML7213/ML7223/ML7831, a companion chip + for the Atom E6xx series and compatible with the Intel EG20T PCH. + +config SPI_TXX9 + tristate "Toshiba TXx9 SPI controller" + depends on GPIOLIB && (CPU_TX49XX || COMPILE_TEST) + help + SPI driver for Toshiba TXx9 MIPS SoCs + +config SPI_XCOMM + tristate "Analog Devices AD-FMCOMMS1-EBZ SPI-I2C-bridge driver" + depends on I2C + help + Support for the SPI-I2C bridge found on the Analog Devices + AD-FMCOMMS1-EBZ board. + +config SPI_XILINX + tristate "Xilinx SPI controller common module" + depends on HAS_IOMEM + select SPI_BITBANG + help + This exposes the SPI controller IP from the Xilinx EDK. + + See the "OPB Serial Peripheral Interface (SPI) (v1.00e)" + Product Specification document (DS464) for hardware details. + + Or for the DS570, see "XPS Serial Peripheral Interface (SPI) (v2.00b)" + +config SPI_XTENSA_XTFPGA + tristate "Xtensa SPI controller for xtfpga" + depends on (XTENSA && XTENSA_PLATFORM_XTFPGA) || COMPILE_TEST + select SPI_BITBANG + help + SPI driver for xtfpga SPI master controller. + + This simple SPI master controller is built into xtfpga bitstreams + and is used to control daughterboard audio codec. It always transfers + 16 bit words in SPI mode 0, automatically asserting CS on transfer + start and deasserting on end. + +config SPI_NUC900 + tristate "Nuvoton NUC900 series SPI" + depends on ARCH_W90X900 + select SPI_BITBANG + help + SPI driver for Nuvoton NUC900 series ARM SoCs + +# +# Add new SPI master controllers in alphabetical order above this line +# + +config SPI_DESIGNWARE + tristate "DesignWare SPI controller core support" + help + general driver for SPI controller core from DesignWare + +config SPI_DW_PCI + tristate "PCI interface driver for DW SPI core" + depends on SPI_DESIGNWARE && PCI + +config SPI_DW_MID_DMA + bool "DMA support for DW SPI controller on Intel MID platform" + depends on SPI_DW_PCI && DW_DMAC_PCI + +config SPI_DW_MMIO + tristate "Memory-mapped io interface driver for DW SPI core" + depends on SPI_DESIGNWARE + +# +# There are lots of SPI device types, with sensors and memory +# being probably the most widely used ones. +# +comment "SPI Protocol Masters" + +config SPI_SPIDEV + tristate "User mode SPI device driver support" + help + This supports user mode SPI protocol drivers. + + Note that this application programming interface is EXPERIMENTAL + and hence SUBJECT TO CHANGE WITHOUT NOTICE while it stabilizes. + +config SPI_TLE62X0 + tristate "Infineon TLE62X0 (for power switching)" + depends on SYSFS + help + SPI driver for Infineon TLE62X0 series line driver chips, + such as the TLE6220, TLE6230 and TLE6240. This provides a + sysfs interface, with each line presented as a kind of GPIO + exposing both switch control and diagnostic feedback. + +# +# Add new SPI protocol masters in alphabetical order above this line +# + +endif # SPI_MASTER + +# (slave support would go here) + +endif # SPI diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile new file mode 100644 index 000000000..d8cbf6549 --- /dev/null +++ b/drivers/spi/Makefile @@ -0,0 +1,91 @@ +# +# Makefile for kernel SPI drivers. +# + +ccflags-$(CONFIG_SPI_DEBUG) := -DDEBUG + +# small core, mostly translating board-specific +# config declarations into driver model code +obj-$(CONFIG_SPI_MASTER) += spi.o +obj-$(CONFIG_SPI_SPIDEV) += spidev.o + +# SPI master controller drivers (bus) +obj-$(CONFIG_SPI_ALTERA) += spi-altera.o +obj-$(CONFIG_SPI_ATMEL) += spi-atmel.o +obj-$(CONFIG_SPI_ATH79) += spi-ath79.o +obj-$(CONFIG_SPI_AU1550) += spi-au1550.o +obj-$(CONFIG_SPI_BCM2835) += spi-bcm2835.o +obj-$(CONFIG_SPI_BCM53XX) += spi-bcm53xx.o +obj-$(CONFIG_SPI_BCM63XX) += spi-bcm63xx.o +obj-$(CONFIG_SPI_BCM63XX_HSSPI) += spi-bcm63xx-hsspi.o +obj-$(CONFIG_SPI_BFIN5XX) += spi-bfin5xx.o +obj-$(CONFIG_SPI_ADI_V3) += spi-adi-v3.o +obj-$(CONFIG_SPI_BFIN_SPORT) += spi-bfin-sport.o +obj-$(CONFIG_SPI_BITBANG) += spi-bitbang.o +obj-$(CONFIG_SPI_BUTTERFLY) += spi-butterfly.o +obj-$(CONFIG_SPI_CADENCE) += spi-cadence.o +obj-$(CONFIG_SPI_CLPS711X) += spi-clps711x.o +obj-$(CONFIG_SPI_COLDFIRE_QSPI) += spi-coldfire-qspi.o +obj-$(CONFIG_SPI_DAVINCI) += spi-davinci.o +obj-$(CONFIG_SPI_DLN2) += spi-dln2.o +obj-$(CONFIG_SPI_DESIGNWARE) += spi-dw.o +obj-$(CONFIG_SPI_DW_MMIO) += spi-dw-mmio.o +obj-$(CONFIG_SPI_DW_PCI) += spi-dw-midpci.o +spi-dw-midpci-objs := spi-dw-pci.o spi-dw-mid.o +obj-$(CONFIG_SPI_EFM32) += spi-efm32.o +obj-$(CONFIG_SPI_EP93XX) += spi-ep93xx.o +obj-$(CONFIG_SPI_FALCON) += spi-falcon.o +obj-$(CONFIG_SPI_FSL_CPM) += spi-fsl-cpm.o +obj-$(CONFIG_SPI_FSL_DSPI) += spi-fsl-dspi.o +obj-$(CONFIG_SPI_FSL_LIB) += spi-fsl-lib.o +obj-$(CONFIG_SPI_FSL_ESPI) += spi-fsl-espi.o +obj-$(CONFIG_SPI_FSL_SPI) += spi-fsl-spi.o +obj-$(CONFIG_SPI_GPIO) += spi-gpio.o +obj-$(CONFIG_SPI_IMG_SPFI) += spi-img-spfi.o +obj-$(CONFIG_SPI_IMX) += spi-imx.o +obj-$(CONFIG_SPI_LM70_LLP) += spi-lm70llp.o +obj-$(CONFIG_SPI_MESON_SPIFC) += spi-meson-spifc.o +obj-$(CONFIG_SPI_MPC512x_PSC) += spi-mpc512x-psc.o +obj-$(CONFIG_SPI_MPC52xx_PSC) += spi-mpc52xx-psc.o +obj-$(CONFIG_SPI_MPC52xx) += spi-mpc52xx.o +obj-$(CONFIG_SPI_MXS) += spi-mxs.o +obj-$(CONFIG_SPI_NUC900) += spi-nuc900.o +obj-$(CONFIG_SPI_OC_TINY) += spi-oc-tiny.o +obj-$(CONFIG_SPI_OCTEON) += spi-octeon.o +obj-$(CONFIG_SPI_OMAP_UWIRE) += spi-omap-uwire.o +obj-$(CONFIG_SPI_OMAP_100K) += spi-omap-100k.o +obj-$(CONFIG_SPI_OMAP24XX) += spi-omap2-mcspi.o +obj-$(CONFIG_SPI_TI_QSPI) += spi-ti-qspi.o +obj-$(CONFIG_SPI_ORION) += spi-orion.o +obj-$(CONFIG_SPI_PL022) += spi-pl022.o +obj-$(CONFIG_SPI_PPC4xx) += spi-ppc4xx.o +spi-pxa2xx-platform-objs := spi-pxa2xx.o +spi-pxa2xx-platform-$(CONFIG_SPI_PXA2XX_PXADMA) += spi-pxa2xx-pxadma.o +spi-pxa2xx-platform-$(CONFIG_SPI_PXA2XX_DMA) += spi-pxa2xx-dma.o +obj-$(CONFIG_SPI_PXA2XX) += spi-pxa2xx-platform.o +obj-$(CONFIG_SPI_PXA2XX_PCI) += spi-pxa2xx-pci.o +obj-$(CONFIG_SPI_QUP) += spi-qup.o +obj-$(CONFIG_SPI_ROCKCHIP) += spi-rockchip.o +obj-$(CONFIG_SPI_RSPI) += spi-rspi.o +obj-$(CONFIG_SPI_S3C24XX) += spi-s3c24xx-hw.o +spi-s3c24xx-hw-y := spi-s3c24xx.o +spi-s3c24xx-hw-$(CONFIG_SPI_S3C24XX_FIQ) += spi-s3c24xx-fiq.o +obj-$(CONFIG_SPI_S3C64XX) += spi-s3c64xx.o +obj-$(CONFIG_SPI_SC18IS602) += spi-sc18is602.o +obj-$(CONFIG_SPI_SH) += spi-sh.o +obj-$(CONFIG_SPI_SH_HSPI) += spi-sh-hspi.o +obj-$(CONFIG_SPI_SH_MSIOF) += spi-sh-msiof.o +obj-$(CONFIG_SPI_SH_SCI) += spi-sh-sci.o +obj-$(CONFIG_SPI_SIRF) += spi-sirf.o +obj-$(CONFIG_SPI_ST_SSC4) += spi-st-ssc4.o +obj-$(CONFIG_SPI_SUN4I) += spi-sun4i.o +obj-$(CONFIG_SPI_SUN6I) += spi-sun6i.o +obj-$(CONFIG_SPI_TEGRA114) += spi-tegra114.o +obj-$(CONFIG_SPI_TEGRA20_SFLASH) += spi-tegra20-sflash.o +obj-$(CONFIG_SPI_TEGRA20_SLINK) += spi-tegra20-slink.o +obj-$(CONFIG_SPI_TLE62X0) += spi-tle62x0.o +obj-$(CONFIG_SPI_TOPCLIFF_PCH) += spi-topcliff-pch.o +obj-$(CONFIG_SPI_TXX9) += spi-txx9.o +obj-$(CONFIG_SPI_XCOMM) += spi-xcomm.o +obj-$(CONFIG_SPI_XILINX) += spi-xilinx.o +obj-$(CONFIG_SPI_XTENSA_XTFPGA) += spi-xtensa-xtfpga.o diff --git a/drivers/spi/spi-adi-v3.c b/drivers/spi/spi-adi-v3.c new file mode 100644 index 000000000..a16b25dcd --- /dev/null +++ b/drivers/spi/spi-adi-v3.c @@ -0,0 +1,984 @@ +/* + * Analog Devices SPI3 controller driver + * + * Copyright (c) 2014 Analog Devices Inc. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/dma-mapping.h> +#include <linux/errno.h> +#include <linux/gpio.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/ioport.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/spi/spi.h> +#include <linux/spi/adi_spi3.h> +#include <linux/types.h> + +#include <asm/dma.h> +#include <asm/portmux.h> + +enum adi_spi_state { + START_STATE, + RUNNING_STATE, + DONE_STATE, + ERROR_STATE +}; + +struct adi_spi_master; + +struct adi_spi_transfer_ops { + void (*write) (struct adi_spi_master *); + void (*read) (struct adi_spi_master *); + void (*duplex) (struct adi_spi_master *); +}; + +/* runtime info for spi master */ +struct adi_spi_master { + /* SPI framework hookup */ + struct spi_master *master; + + /* Regs base of SPI controller */ + struct adi_spi_regs __iomem *regs; + + /* Pin request list */ + u16 *pin_req; + + /* Message Transfer pump */ + struct tasklet_struct pump_transfers; + + /* Current message transfer state info */ + struct spi_message *cur_msg; + struct spi_transfer *cur_transfer; + struct adi_spi_device *cur_chip; + unsigned transfer_len; + + /* transfer buffer */ + void *tx; + void *tx_end; + void *rx; + void *rx_end; + + /* dma info */ + unsigned int tx_dma; + unsigned int rx_dma; + dma_addr_t tx_dma_addr; + dma_addr_t rx_dma_addr; + unsigned long dummy_buffer; /* used in unidirectional transfer */ + unsigned long tx_dma_size; + unsigned long rx_dma_size; + int tx_num; + int rx_num; + + /* store register value for suspend/resume */ + u32 control; + u32 ssel; + + unsigned long sclk; + enum adi_spi_state state; + + const struct adi_spi_transfer_ops *ops; +}; + +struct adi_spi_device { + u32 control; + u32 clock; + u32 ssel; + + u8 cs; + u16 cs_chg_udelay; /* Some devices require > 255usec delay */ + u32 cs_gpio; + u32 tx_dummy_val; /* tx value for rx only transfer */ + bool enable_dma; + const struct adi_spi_transfer_ops *ops; +}; + +static void adi_spi_enable(struct adi_spi_master *drv_data) +{ + u32 ctl; + + ctl = ioread32(&drv_data->regs->control); + ctl |= SPI_CTL_EN; + iowrite32(ctl, &drv_data->regs->control); +} + +static void adi_spi_disable(struct adi_spi_master *drv_data) +{ + u32 ctl; + + ctl = ioread32(&drv_data->regs->control); + ctl &= ~SPI_CTL_EN; + iowrite32(ctl, &drv_data->regs->control); +} + +/* Caculate the SPI_CLOCK register value based on input HZ */ +static u32 hz_to_spi_clock(u32 sclk, u32 speed_hz) +{ + u32 spi_clock = sclk / speed_hz; + + if (spi_clock) + spi_clock--; + return spi_clock; +} + +static int adi_spi_flush(struct adi_spi_master *drv_data) +{ + unsigned long limit = loops_per_jiffy << 1; + + /* wait for stop and clear stat */ + while (!(ioread32(&drv_data->regs->status) & SPI_STAT_SPIF) && --limit) + cpu_relax(); + + iowrite32(0xFFFFFFFF, &drv_data->regs->status); + + return limit; +} + +/* Chip select operation functions for cs_change flag */ +static void adi_spi_cs_active(struct adi_spi_master *drv_data, struct adi_spi_device *chip) +{ + if (likely(chip->cs < MAX_CTRL_CS)) { + u32 reg; + reg = ioread32(&drv_data->regs->ssel); + reg &= ~chip->ssel; + iowrite32(reg, &drv_data->regs->ssel); + } else { + gpio_set_value(chip->cs_gpio, 0); + } +} + +static void adi_spi_cs_deactive(struct adi_spi_master *drv_data, + struct adi_spi_device *chip) +{ + if (likely(chip->cs < MAX_CTRL_CS)) { + u32 reg; + reg = ioread32(&drv_data->regs->ssel); + reg |= chip->ssel; + iowrite32(reg, &drv_data->regs->ssel); + } else { + gpio_set_value(chip->cs_gpio, 1); + } + + /* Move delay here for consistency */ + if (chip->cs_chg_udelay) + udelay(chip->cs_chg_udelay); +} + +/* enable or disable the pin muxed by GPIO and SPI CS to work as SPI CS */ +static inline void adi_spi_cs_enable(struct adi_spi_master *drv_data, + struct adi_spi_device *chip) +{ + if (chip->cs < MAX_CTRL_CS) { + u32 reg; + reg = ioread32(&drv_data->regs->ssel); + reg |= chip->ssel >> 8; + iowrite32(reg, &drv_data->regs->ssel); + } +} + +static inline void adi_spi_cs_disable(struct adi_spi_master *drv_data, + struct adi_spi_device *chip) +{ + if (chip->cs < MAX_CTRL_CS) { + u32 reg; + reg = ioread32(&drv_data->regs->ssel); + reg &= ~(chip->ssel >> 8); + iowrite32(reg, &drv_data->regs->ssel); + } +} + +/* stop controller and re-config current chip*/ +static void adi_spi_restore_state(struct adi_spi_master *drv_data) +{ + struct adi_spi_device *chip = drv_data->cur_chip; + + /* Clear status and disable clock */ + iowrite32(0xFFFFFFFF, &drv_data->regs->status); + iowrite32(0x0, &drv_data->regs->rx_control); + iowrite32(0x0, &drv_data->regs->tx_control); + adi_spi_disable(drv_data); + + /* Load the registers */ + iowrite32(chip->control, &drv_data->regs->control); + iowrite32(chip->clock, &drv_data->regs->clock); + + adi_spi_enable(drv_data); + drv_data->tx_num = drv_data->rx_num = 0; + /* we always choose tx transfer initiate */ + iowrite32(SPI_RXCTL_REN, &drv_data->regs->rx_control); + iowrite32(SPI_TXCTL_TEN | SPI_TXCTL_TTI, &drv_data->regs->tx_control); + adi_spi_cs_active(drv_data, chip); +} + +/* discard invalid rx data and empty rfifo */ +static inline void dummy_read(struct adi_spi_master *drv_data) +{ + while (!(ioread32(&drv_data->regs->status) & SPI_STAT_RFE)) + ioread32(&drv_data->regs->rfifo); +} + +static void adi_spi_u8_write(struct adi_spi_master *drv_data) +{ + dummy_read(drv_data); + while (drv_data->tx < drv_data->tx_end) { + iowrite32(*(u8 *)(drv_data->tx++), &drv_data->regs->tfifo); + while (ioread32(&drv_data->regs->status) & SPI_STAT_RFE) + cpu_relax(); + ioread32(&drv_data->regs->rfifo); + } +} + +static void adi_spi_u8_read(struct adi_spi_master *drv_data) +{ + u32 tx_val = drv_data->cur_chip->tx_dummy_val; + + dummy_read(drv_data); + while (drv_data->rx < drv_data->rx_end) { + iowrite32(tx_val, &drv_data->regs->tfifo); + while (ioread32(&drv_data->regs->status) & SPI_STAT_RFE) + cpu_relax(); + *(u8 *)(drv_data->rx++) = ioread32(&drv_data->regs->rfifo); + } +} + +static void adi_spi_u8_duplex(struct adi_spi_master *drv_data) +{ + dummy_read(drv_data); + while (drv_data->rx < drv_data->rx_end) { + iowrite32(*(u8 *)(drv_data->tx++), &drv_data->regs->tfifo); + while (ioread32(&drv_data->regs->status) & SPI_STAT_RFE) + cpu_relax(); + *(u8 *)(drv_data->rx++) = ioread32(&drv_data->regs->rfifo); + } +} + +static const struct adi_spi_transfer_ops adi_spi_transfer_ops_u8 = { + .write = adi_spi_u8_write, + .read = adi_spi_u8_read, + .duplex = adi_spi_u8_duplex, +}; + +static void adi_spi_u16_write(struct adi_spi_master *drv_data) +{ + dummy_read(drv_data); + while (drv_data->tx < drv_data->tx_end) { + iowrite32(*(u16 *)drv_data->tx, &drv_data->regs->tfifo); + drv_data->tx += 2; + while (ioread32(&drv_data->regs->status) & SPI_STAT_RFE) + cpu_relax(); + ioread32(&drv_data->regs->rfifo); + } +} + +static void adi_spi_u16_read(struct adi_spi_master *drv_data) +{ + u32 tx_val = drv_data->cur_chip->tx_dummy_val; + + dummy_read(drv_data); + while (drv_data->rx < drv_data->rx_end) { + iowrite32(tx_val, &drv_data->regs->tfifo); + while (ioread32(&drv_data->regs->status) & SPI_STAT_RFE) + cpu_relax(); + *(u16 *)drv_data->rx = ioread32(&drv_data->regs->rfifo); + drv_data->rx += 2; + } +} + +static void adi_spi_u16_duplex(struct adi_spi_master *drv_data) +{ + dummy_read(drv_data); + while (drv_data->rx < drv_data->rx_end) { + iowrite32(*(u16 *)drv_data->tx, &drv_data->regs->tfifo); + drv_data->tx += 2; + while (ioread32(&drv_data->regs->status) & SPI_STAT_RFE) + cpu_relax(); + *(u16 *)drv_data->rx = ioread32(&drv_data->regs->rfifo); + drv_data->rx += 2; + } +} + +static const struct adi_spi_transfer_ops adi_spi_transfer_ops_u16 = { + .write = adi_spi_u16_write, + .read = adi_spi_u16_read, + .duplex = adi_spi_u16_duplex, +}; + +static void adi_spi_u32_write(struct adi_spi_master *drv_data) +{ + dummy_read(drv_data); + while (drv_data->tx < drv_data->tx_end) { + iowrite32(*(u32 *)drv_data->tx, &drv_data->regs->tfifo); + drv_data->tx += 4; + while (ioread32(&drv_data->regs->status) & SPI_STAT_RFE) + cpu_relax(); + ioread32(&drv_data->regs->rfifo); + } +} + +static void adi_spi_u32_read(struct adi_spi_master *drv_data) +{ + u32 tx_val = drv_data->cur_chip->tx_dummy_val; + + dummy_read(drv_data); + while (drv_data->rx < drv_data->rx_end) { + iowrite32(tx_val, &drv_data->regs->tfifo); + while (ioread32(&drv_data->regs->status) & SPI_STAT_RFE) + cpu_relax(); + *(u32 *)drv_data->rx = ioread32(&drv_data->regs->rfifo); + drv_data->rx += 4; + } +} + +static void adi_spi_u32_duplex(struct adi_spi_master *drv_data) +{ + dummy_read(drv_data); + while (drv_data->rx < drv_data->rx_end) { + iowrite32(*(u32 *)drv_data->tx, &drv_data->regs->tfifo); + drv_data->tx += 4; + while (ioread32(&drv_data->regs->status) & SPI_STAT_RFE) + cpu_relax(); + *(u32 *)drv_data->rx = ioread32(&drv_data->regs->rfifo); + drv_data->rx += 4; + } +} + +static const struct adi_spi_transfer_ops adi_spi_transfer_ops_u32 = { + .write = adi_spi_u32_write, + .read = adi_spi_u32_read, + .duplex = adi_spi_u32_duplex, +}; + + +/* test if there is more transfer to be done */ +static void adi_spi_next_transfer(struct adi_spi_master *drv) +{ + struct spi_message *msg = drv->cur_msg; + struct spi_transfer *t = drv->cur_transfer; + + /* Move to next transfer */ + if (t->transfer_list.next != &msg->transfers) { + drv->cur_transfer = list_entry(t->transfer_list.next, + struct spi_transfer, transfer_list); + drv->state = RUNNING_STATE; + } else { + drv->state = DONE_STATE; + drv->cur_transfer = NULL; + } +} + +static void adi_spi_giveback(struct adi_spi_master *drv_data) +{ + struct adi_spi_device *chip = drv_data->cur_chip; + + adi_spi_cs_deactive(drv_data, chip); + spi_finalize_current_message(drv_data->master); +} + +static int adi_spi_setup_transfer(struct adi_spi_master *drv) +{ + struct spi_transfer *t = drv->cur_transfer; + u32 cr, cr_width; + + if (t->tx_buf) { + drv->tx = (void *)t->tx_buf; + drv->tx_end = drv->tx + t->len; + } else { + drv->tx = NULL; + } + + if (t->rx_buf) { + drv->rx = t->rx_buf; + drv->rx_end = drv->rx + t->len; + } else { + drv->rx = NULL; + } + + drv->transfer_len = t->len; + + /* bits per word setup */ + switch (t->bits_per_word) { + case 8: + cr_width = SPI_CTL_SIZE08; + drv->ops = &adi_spi_transfer_ops_u8; + break; + case 16: + cr_width = SPI_CTL_SIZE16; + drv->ops = &adi_spi_transfer_ops_u16; + break; + case 32: + cr_width = SPI_CTL_SIZE32; + drv->ops = &adi_spi_transfer_ops_u32; + break; + default: + return -EINVAL; + } + cr = ioread32(&drv->regs->control) & ~SPI_CTL_SIZE; + cr |= cr_width; + iowrite32(cr, &drv->regs->control); + + /* speed setup */ + iowrite32(hz_to_spi_clock(drv->sclk, t->speed_hz), &drv->regs->clock); + return 0; +} + +static int adi_spi_dma_xfer(struct adi_spi_master *drv_data) +{ + struct spi_transfer *t = drv_data->cur_transfer; + struct spi_message *msg = drv_data->cur_msg; + struct adi_spi_device *chip = drv_data->cur_chip; + u32 dma_config; + unsigned long word_count, word_size; + void *tx_buf, *rx_buf; + + switch (t->bits_per_word) { + case 8: + dma_config = WDSIZE_8 | PSIZE_8; + word_count = drv_data->transfer_len; + word_size = 1; + break; + case 16: + dma_config = WDSIZE_16 | PSIZE_16; + word_count = drv_data->transfer_len / 2; + word_size = 2; + break; + default: + dma_config = WDSIZE_32 | PSIZE_32; + word_count = drv_data->transfer_len / 4; + word_size = 4; + break; + } + + if (!drv_data->rx) { + tx_buf = drv_data->tx; + rx_buf = &drv_data->dummy_buffer; + drv_data->tx_dma_size = drv_data->transfer_len; + drv_data->rx_dma_size = sizeof(drv_data->dummy_buffer); + set_dma_x_modify(drv_data->tx_dma, word_size); + set_dma_x_modify(drv_data->rx_dma, 0); + } else if (!drv_data->tx) { + drv_data->dummy_buffer = chip->tx_dummy_val; + tx_buf = &drv_data->dummy_buffer; + rx_buf = drv_data->rx; + drv_data->tx_dma_size = sizeof(drv_data->dummy_buffer); + drv_data->rx_dma_size = drv_data->transfer_len; + set_dma_x_modify(drv_data->tx_dma, 0); + set_dma_x_modify(drv_data->rx_dma, word_size); + } else { + tx_buf = drv_data->tx; + rx_buf = drv_data->rx; + drv_data->tx_dma_size = drv_data->rx_dma_size + = drv_data->transfer_len; + set_dma_x_modify(drv_data->tx_dma, word_size); + set_dma_x_modify(drv_data->rx_dma, word_size); + } + + drv_data->tx_dma_addr = dma_map_single(&msg->spi->dev, + (void *)tx_buf, + drv_data->tx_dma_size, + DMA_TO_DEVICE); + if (dma_mapping_error(&msg->spi->dev, + drv_data->tx_dma_addr)) + return -ENOMEM; + + drv_data->rx_dma_addr = dma_map_single(&msg->spi->dev, + (void *)rx_buf, + drv_data->rx_dma_size, + DMA_FROM_DEVICE); + if (dma_mapping_error(&msg->spi->dev, + drv_data->rx_dma_addr)) { + dma_unmap_single(&msg->spi->dev, + drv_data->tx_dma_addr, + drv_data->tx_dma_size, + DMA_TO_DEVICE); + return -ENOMEM; + } + + dummy_read(drv_data); + set_dma_x_count(drv_data->tx_dma, word_count); + set_dma_x_count(drv_data->rx_dma, word_count); + set_dma_start_addr(drv_data->tx_dma, drv_data->tx_dma_addr); + set_dma_start_addr(drv_data->rx_dma, drv_data->rx_dma_addr); + dma_config |= DMAFLOW_STOP | RESTART | DI_EN; + set_dma_config(drv_data->tx_dma, dma_config); + set_dma_config(drv_data->rx_dma, dma_config | WNR); + enable_dma(drv_data->tx_dma); + enable_dma(drv_data->rx_dma); + + iowrite32(SPI_RXCTL_REN | SPI_RXCTL_RDR_NE, + &drv_data->regs->rx_control); + iowrite32(SPI_TXCTL_TEN | SPI_TXCTL_TTI | SPI_TXCTL_TDR_NF, + &drv_data->regs->tx_control); + + return 0; +} + +static int adi_spi_pio_xfer(struct adi_spi_master *drv_data) +{ + struct spi_message *msg = drv_data->cur_msg; + + if (!drv_data->rx) { + /* write only half duplex */ + drv_data->ops->write(drv_data); + if (drv_data->tx != drv_data->tx_end) + return -EIO; + } else if (!drv_data->tx) { + /* read only half duplex */ + drv_data->ops->read(drv_data); + if (drv_data->rx != drv_data->rx_end) + return -EIO; + } else { + /* full duplex mode */ + drv_data->ops->duplex(drv_data); + if (drv_data->tx != drv_data->tx_end) + return -EIO; + } + + if (!adi_spi_flush(drv_data)) + return -EIO; + msg->actual_length += drv_data->transfer_len; + tasklet_schedule(&drv_data->pump_transfers); + return 0; +} + +static void adi_spi_pump_transfers(unsigned long data) +{ + struct adi_spi_master *drv_data = (struct adi_spi_master *)data; + struct spi_message *msg = NULL; + struct spi_transfer *t = NULL; + struct adi_spi_device *chip = NULL; + int ret; + + /* Get current state information */ + msg = drv_data->cur_msg; + t = drv_data->cur_transfer; + chip = drv_data->cur_chip; + + /* Handle for abort */ + if (drv_data->state == ERROR_STATE) { + msg->status = -EIO; + adi_spi_giveback(drv_data); + return; + } + + if (drv_data->state == RUNNING_STATE) { + if (t->delay_usecs) + udelay(t->delay_usecs); + if (t->cs_change) + adi_spi_cs_deactive(drv_data, chip); + adi_spi_next_transfer(drv_data); + t = drv_data->cur_transfer; + } + /* Handle end of message */ + if (drv_data->state == DONE_STATE) { + msg->status = 0; + adi_spi_giveback(drv_data); + return; + } + + if ((t->len == 0) || (t->tx_buf == NULL && t->rx_buf == NULL)) { + /* Schedule next transfer tasklet */ + tasklet_schedule(&drv_data->pump_transfers); + return; + } + + ret = adi_spi_setup_transfer(drv_data); + if (ret) { + msg->status = ret; + adi_spi_giveback(drv_data); + } + + iowrite32(0xFFFFFFFF, &drv_data->regs->status); + adi_spi_cs_active(drv_data, chip); + drv_data->state = RUNNING_STATE; + + if (chip->enable_dma) + ret = adi_spi_dma_xfer(drv_data); + else + ret = adi_spi_pio_xfer(drv_data); + if (ret) { + msg->status = ret; + adi_spi_giveback(drv_data); + } +} + +static int adi_spi_transfer_one_message(struct spi_master *master, + struct spi_message *m) +{ + struct adi_spi_master *drv_data = spi_master_get_devdata(master); + + drv_data->cur_msg = m; + drv_data->cur_chip = spi_get_ctldata(drv_data->cur_msg->spi); + adi_spi_restore_state(drv_data); + + drv_data->state = START_STATE; + drv_data->cur_transfer = list_entry(drv_data->cur_msg->transfers.next, + struct spi_transfer, transfer_list); + + tasklet_schedule(&drv_data->pump_transfers); + return 0; +} + +#define MAX_SPI_SSEL 7 + +static const u16 ssel[][MAX_SPI_SSEL] = { + {P_SPI0_SSEL1, P_SPI0_SSEL2, P_SPI0_SSEL3, + P_SPI0_SSEL4, P_SPI0_SSEL5, + P_SPI0_SSEL6, P_SPI0_SSEL7}, + + {P_SPI1_SSEL1, P_SPI1_SSEL2, P_SPI1_SSEL3, + P_SPI1_SSEL4, P_SPI1_SSEL5, + P_SPI1_SSEL6, P_SPI1_SSEL7}, + + {P_SPI2_SSEL1, P_SPI2_SSEL2, P_SPI2_SSEL3, + P_SPI2_SSEL4, P_SPI2_SSEL5, + P_SPI2_SSEL6, P_SPI2_SSEL7}, +}; + +static int adi_spi_setup(struct spi_device *spi) +{ + struct adi_spi_master *drv_data = spi_master_get_devdata(spi->master); + struct adi_spi_device *chip = spi_get_ctldata(spi); + u32 ctl_reg = SPI_CTL_ODM | SPI_CTL_PSSE; + int ret = -EINVAL; + + if (!chip) { + struct adi_spi3_chip *chip_info = spi->controller_data; + + chip = kzalloc(sizeof(*chip), GFP_KERNEL); + if (!chip) + return -ENOMEM; + + if (chip_info) { + if (chip_info->control & ~ctl_reg) { + dev_err(&spi->dev, + "do not set bits that the SPI framework manages\n"); + goto error; + } + chip->control = chip_info->control; + chip->cs_chg_udelay = chip_info->cs_chg_udelay; + chip->tx_dummy_val = chip_info->tx_dummy_val; + chip->enable_dma = chip_info->enable_dma; + } + chip->cs = spi->chip_select; + + if (chip->cs < MAX_CTRL_CS) { + chip->ssel = (1 << chip->cs) << 8; + ret = peripheral_request(ssel[spi->master->bus_num] + [chip->cs-1], dev_name(&spi->dev)); + if (ret) { + dev_err(&spi->dev, "peripheral_request() error\n"); + goto error; + } + } else { + chip->cs_gpio = chip->cs - MAX_CTRL_CS; + ret = gpio_request_one(chip->cs_gpio, GPIOF_OUT_INIT_HIGH, + dev_name(&spi->dev)); + if (ret) { + dev_err(&spi->dev, "gpio_request_one() error\n"); + goto error; + } + } + spi_set_ctldata(spi, chip); + } + + /* force a default base state */ + chip->control &= ctl_reg; + + if (spi->mode & SPI_CPOL) + chip->control |= SPI_CTL_CPOL; + if (spi->mode & SPI_CPHA) + chip->control |= SPI_CTL_CPHA; + if (spi->mode & SPI_LSB_FIRST) + chip->control |= SPI_CTL_LSBF; + chip->control |= SPI_CTL_MSTR; + /* we choose software to controll cs */ + chip->control &= ~SPI_CTL_ASSEL; + + chip->clock = hz_to_spi_clock(drv_data->sclk, spi->max_speed_hz); + + adi_spi_cs_enable(drv_data, chip); + adi_spi_cs_deactive(drv_data, chip); + + return 0; +error: + if (chip) { + kfree(chip); + spi_set_ctldata(spi, NULL); + } + + return ret; +} + +static void adi_spi_cleanup(struct spi_device *spi) +{ + struct adi_spi_device *chip = spi_get_ctldata(spi); + struct adi_spi_master *drv_data = spi_master_get_devdata(spi->master); + + if (!chip) + return; + + if (chip->cs < MAX_CTRL_CS) { + peripheral_free(ssel[spi->master->bus_num] + [chip->cs-1]); + adi_spi_cs_disable(drv_data, chip); + } else { + gpio_free(chip->cs_gpio); + } + + kfree(chip); + spi_set_ctldata(spi, NULL); +} + +static irqreturn_t adi_spi_tx_dma_isr(int irq, void *dev_id) +{ + struct adi_spi_master *drv_data = dev_id; + u32 dma_stat = get_dma_curr_irqstat(drv_data->tx_dma); + u32 tx_ctl; + + clear_dma_irqstat(drv_data->tx_dma); + if (dma_stat & DMA_DONE) { + drv_data->tx_num++; + } else { + dev_err(&drv_data->master->dev, + "spi tx dma error: %d\n", dma_stat); + if (drv_data->tx) + drv_data->state = ERROR_STATE; + } + tx_ctl = ioread32(&drv_data->regs->tx_control); + tx_ctl &= ~SPI_TXCTL_TDR_NF; + iowrite32(tx_ctl, &drv_data->regs->tx_control); + return IRQ_HANDLED; +} + +static irqreturn_t adi_spi_rx_dma_isr(int irq, void *dev_id) +{ + struct adi_spi_master *drv_data = dev_id; + struct spi_message *msg = drv_data->cur_msg; + u32 dma_stat = get_dma_curr_irqstat(drv_data->rx_dma); + + clear_dma_irqstat(drv_data->rx_dma); + if (dma_stat & DMA_DONE) { + drv_data->rx_num++; + /* we may fail on tx dma */ + if (drv_data->state != ERROR_STATE) + msg->actual_length += drv_data->transfer_len; + } else { + drv_data->state = ERROR_STATE; + dev_err(&drv_data->master->dev, + "spi rx dma error: %d\n", dma_stat); + } + iowrite32(0, &drv_data->regs->tx_control); + iowrite32(0, &drv_data->regs->rx_control); + if (drv_data->rx_num != drv_data->tx_num) + dev_dbg(&drv_data->master->dev, + "dma interrupt missing: tx=%d,rx=%d\n", + drv_data->tx_num, drv_data->rx_num); + tasklet_schedule(&drv_data->pump_transfers); + return IRQ_HANDLED; +} + +static int adi_spi_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct adi_spi3_master *info = dev_get_platdata(dev); + struct spi_master *master; + struct adi_spi_master *drv_data; + struct resource *mem, *res; + unsigned int tx_dma, rx_dma; + struct clk *sclk; + int ret; + + if (!info) { + dev_err(dev, "platform data missing!\n"); + return -ENODEV; + } + + sclk = devm_clk_get(dev, "spi"); + if (IS_ERR(sclk)) { + dev_err(dev, "can not get spi clock\n"); + return PTR_ERR(sclk); + } + + res = platform_get_resource(pdev, IORESOURCE_DMA, 0); + if (!res) { + dev_err(dev, "can not get tx dma resource\n"); + return -ENXIO; + } + tx_dma = res->start; + + res = platform_get_resource(pdev, IORESOURCE_DMA, 1); + if (!res) { + dev_err(dev, "can not get rx dma resource\n"); + return -ENXIO; + } + rx_dma = res->start; + + /* allocate master with space for drv_data */ + master = spi_alloc_master(dev, sizeof(*drv_data)); + if (!master) { + dev_err(dev, "can not alloc spi_master\n"); + return -ENOMEM; + } + platform_set_drvdata(pdev, master); + + /* the mode bits supported by this driver */ + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST; + + master->bus_num = pdev->id; + master->num_chipselect = info->num_chipselect; + master->cleanup = adi_spi_cleanup; + master->setup = adi_spi_setup; + master->transfer_one_message = adi_spi_transfer_one_message; + master->bits_per_word_mask = SPI_BPW_MASK(32) | SPI_BPW_MASK(16) | + SPI_BPW_MASK(8); + + drv_data = spi_master_get_devdata(master); + drv_data->master = master; + drv_data->tx_dma = tx_dma; + drv_data->rx_dma = rx_dma; + drv_data->pin_req = info->pin_req; + drv_data->sclk = clk_get_rate(sclk); + + mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); + drv_data->regs = devm_ioremap_resource(dev, mem); + if (IS_ERR(drv_data->regs)) { + ret = PTR_ERR(drv_data->regs); + goto err_put_master; + } + + /* request tx and rx dma */ + ret = request_dma(tx_dma, "SPI_TX_DMA"); + if (ret) { + dev_err(dev, "can not request SPI TX DMA channel\n"); + goto err_put_master; + } + set_dma_callback(tx_dma, adi_spi_tx_dma_isr, drv_data); + + ret = request_dma(rx_dma, "SPI_RX_DMA"); + if (ret) { + dev_err(dev, "can not request SPI RX DMA channel\n"); + goto err_free_tx_dma; + } + set_dma_callback(drv_data->rx_dma, adi_spi_rx_dma_isr, drv_data); + + /* request CLK, MOSI and MISO */ + ret = peripheral_request_list(drv_data->pin_req, "adi-spi3"); + if (ret < 0) { + dev_err(dev, "can not request spi pins\n"); + goto err_free_rx_dma; + } + + iowrite32(SPI_CTL_MSTR | SPI_CTL_CPHA, &drv_data->regs->control); + iowrite32(0x0000FE00, &drv_data->regs->ssel); + iowrite32(0x0, &drv_data->regs->delay); + + tasklet_init(&drv_data->pump_transfers, + adi_spi_pump_transfers, (unsigned long)drv_data); + /* register with the SPI framework */ + ret = devm_spi_register_master(dev, master); + if (ret) { + dev_err(dev, "can not register spi master\n"); + goto err_free_peripheral; + } + + return ret; + +err_free_peripheral: + peripheral_free_list(drv_data->pin_req); +err_free_rx_dma: + free_dma(rx_dma); +err_free_tx_dma: + free_dma(tx_dma); +err_put_master: + spi_master_put(master); + + return ret; +} + +static int adi_spi_remove(struct platform_device *pdev) +{ + struct spi_master *master = platform_get_drvdata(pdev); + struct adi_spi_master *drv_data = spi_master_get_devdata(master); + + adi_spi_disable(drv_data); + peripheral_free_list(drv_data->pin_req); + free_dma(drv_data->rx_dma); + free_dma(drv_data->tx_dma); + return 0; +} + +#ifdef CONFIG_PM +static int adi_spi_suspend(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct adi_spi_master *drv_data = spi_master_get_devdata(master); + + spi_master_suspend(master); + + drv_data->control = ioread32(&drv_data->regs->control); + drv_data->ssel = ioread32(&drv_data->regs->ssel); + + iowrite32(SPI_CTL_MSTR | SPI_CTL_CPHA, &drv_data->regs->control); + iowrite32(0x0000FE00, &drv_data->regs->ssel); + dma_disable_irq(drv_data->rx_dma); + dma_disable_irq(drv_data->tx_dma); + + return 0; +} + +static int adi_spi_resume(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct adi_spi_master *drv_data = spi_master_get_devdata(master); + int ret = 0; + + /* bootrom may modify spi and dma status when resume in spi boot mode */ + disable_dma(drv_data->rx_dma); + + dma_enable_irq(drv_data->rx_dma); + dma_enable_irq(drv_data->tx_dma); + iowrite32(drv_data->control, &drv_data->regs->control); + iowrite32(drv_data->ssel, &drv_data->regs->ssel); + + ret = spi_master_resume(master); + if (ret) { + free_dma(drv_data->rx_dma); + free_dma(drv_data->tx_dma); + } + + return ret; +} +#endif +static const struct dev_pm_ops adi_spi_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(adi_spi_suspend, adi_spi_resume) +}; + +MODULE_ALIAS("platform:adi-spi3"); +static struct platform_driver adi_spi_driver = { + .driver = { + .name = "adi-spi3", + .pm = &adi_spi_pm_ops, + }, + .remove = adi_spi_remove, +}; + +module_platform_driver_probe(adi_spi_driver, adi_spi_probe); + +MODULE_DESCRIPTION("Analog Devices SPI3 controller driver"); +MODULE_AUTHOR("Scott Jiang <Scott.Jiang.Linux@gmail.com>"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/spi/spi-altera.c b/drivers/spi/spi-altera.c new file mode 100644 index 000000000..b95010e72 --- /dev/null +++ b/drivers/spi/spi-altera.c @@ -0,0 +1,294 @@ +/* + * Altera SPI driver + * + * Copyright (C) 2008 Thomas Chou <thomas@wytron.com.tw> + * + * Based on spi_s3c24xx.c, which is: + * Copyright (c) 2006 Ben Dooks + * Copyright (c) 2006 Simtec Electronics + * Ben Dooks <ben@simtec.co.uk> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/interrupt.h> +#include <linux/errno.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/spi/spi.h> +#include <linux/spi/spi_bitbang.h> +#include <linux/io.h> +#include <linux/of.h> + +#define DRV_NAME "spi_altera" + +#define ALTERA_SPI_RXDATA 0 +#define ALTERA_SPI_TXDATA 4 +#define ALTERA_SPI_STATUS 8 +#define ALTERA_SPI_CONTROL 12 +#define ALTERA_SPI_SLAVE_SEL 20 + +#define ALTERA_SPI_STATUS_ROE_MSK 0x8 +#define ALTERA_SPI_STATUS_TOE_MSK 0x10 +#define ALTERA_SPI_STATUS_TMT_MSK 0x20 +#define ALTERA_SPI_STATUS_TRDY_MSK 0x40 +#define ALTERA_SPI_STATUS_RRDY_MSK 0x80 +#define ALTERA_SPI_STATUS_E_MSK 0x100 + +#define ALTERA_SPI_CONTROL_IROE_MSK 0x8 +#define ALTERA_SPI_CONTROL_ITOE_MSK 0x10 +#define ALTERA_SPI_CONTROL_ITRDY_MSK 0x40 +#define ALTERA_SPI_CONTROL_IRRDY_MSK 0x80 +#define ALTERA_SPI_CONTROL_IE_MSK 0x100 +#define ALTERA_SPI_CONTROL_SSO_MSK 0x400 + +struct altera_spi { + /* bitbang has to be first */ + struct spi_bitbang bitbang; + struct completion done; + + void __iomem *base; + int irq; + int len; + int count; + int bytes_per_word; + unsigned long imr; + + /* data buffers */ + const unsigned char *tx; + unsigned char *rx; +}; + +static inline struct altera_spi *altera_spi_to_hw(struct spi_device *sdev) +{ + return spi_master_get_devdata(sdev->master); +} + +static void altera_spi_chipsel(struct spi_device *spi, int value) +{ + struct altera_spi *hw = altera_spi_to_hw(spi); + + if (spi->mode & SPI_CS_HIGH) { + switch (value) { + case BITBANG_CS_INACTIVE: + writel(1 << spi->chip_select, + hw->base + ALTERA_SPI_SLAVE_SEL); + hw->imr |= ALTERA_SPI_CONTROL_SSO_MSK; + writel(hw->imr, hw->base + ALTERA_SPI_CONTROL); + break; + + case BITBANG_CS_ACTIVE: + hw->imr &= ~ALTERA_SPI_CONTROL_SSO_MSK; + writel(hw->imr, hw->base + ALTERA_SPI_CONTROL); + writel(0, hw->base + ALTERA_SPI_SLAVE_SEL); + break; + } + } else { + switch (value) { + case BITBANG_CS_INACTIVE: + hw->imr &= ~ALTERA_SPI_CONTROL_SSO_MSK; + writel(hw->imr, hw->base + ALTERA_SPI_CONTROL); + break; + + case BITBANG_CS_ACTIVE: + writel(1 << spi->chip_select, + hw->base + ALTERA_SPI_SLAVE_SEL); + hw->imr |= ALTERA_SPI_CONTROL_SSO_MSK; + writel(hw->imr, hw->base + ALTERA_SPI_CONTROL); + break; + } + } +} + +static inline unsigned int hw_txbyte(struct altera_spi *hw, int count) +{ + if (hw->tx) { + switch (hw->bytes_per_word) { + case 1: + return hw->tx[count]; + case 2: + return (hw->tx[count * 2] + | (hw->tx[count * 2 + 1] << 8)); + } + } + return 0; +} + +static int altera_spi_txrx(struct spi_device *spi, struct spi_transfer *t) +{ + struct altera_spi *hw = altera_spi_to_hw(spi); + + hw->tx = t->tx_buf; + hw->rx = t->rx_buf; + hw->count = 0; + hw->bytes_per_word = DIV_ROUND_UP(t->bits_per_word, 8); + hw->len = t->len / hw->bytes_per_word; + + if (hw->irq >= 0) { + /* enable receive interrupt */ + hw->imr |= ALTERA_SPI_CONTROL_IRRDY_MSK; + writel(hw->imr, hw->base + ALTERA_SPI_CONTROL); + + /* send the first byte */ + writel(hw_txbyte(hw, 0), hw->base + ALTERA_SPI_TXDATA); + + wait_for_completion(&hw->done); + /* disable receive interrupt */ + hw->imr &= ~ALTERA_SPI_CONTROL_IRRDY_MSK; + writel(hw->imr, hw->base + ALTERA_SPI_CONTROL); + } else { + while (hw->count < hw->len) { + unsigned int rxd; + + writel(hw_txbyte(hw, hw->count), + hw->base + ALTERA_SPI_TXDATA); + + while (!(readl(hw->base + ALTERA_SPI_STATUS) & + ALTERA_SPI_STATUS_RRDY_MSK)) + cpu_relax(); + + rxd = readl(hw->base + ALTERA_SPI_RXDATA); + if (hw->rx) { + switch (hw->bytes_per_word) { + case 1: + hw->rx[hw->count] = rxd; + break; + case 2: + hw->rx[hw->count * 2] = rxd; + hw->rx[hw->count * 2 + 1] = rxd >> 8; + break; + } + } + + hw->count++; + } + } + + return hw->count * hw->bytes_per_word; +} + +static irqreturn_t altera_spi_irq(int irq, void *dev) +{ + struct altera_spi *hw = dev; + unsigned int rxd; + + rxd = readl(hw->base + ALTERA_SPI_RXDATA); + if (hw->rx) { + switch (hw->bytes_per_word) { + case 1: + hw->rx[hw->count] = rxd; + break; + case 2: + hw->rx[hw->count * 2] = rxd; + hw->rx[hw->count * 2 + 1] = rxd >> 8; + break; + } + } + + hw->count++; + + if (hw->count < hw->len) + writel(hw_txbyte(hw, hw->count), hw->base + ALTERA_SPI_TXDATA); + else + complete(&hw->done); + + return IRQ_HANDLED; +} + +static int altera_spi_probe(struct platform_device *pdev) +{ + struct altera_spi *hw; + struct spi_master *master; + struct resource *res; + int err = -ENODEV; + + master = spi_alloc_master(&pdev->dev, sizeof(struct altera_spi)); + if (!master) + return err; + + /* setup the master state. */ + master->bus_num = pdev->id; + master->num_chipselect = 16; + master->mode_bits = SPI_CS_HIGH; + master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 16); + master->dev.of_node = pdev->dev.of_node; + + hw = spi_master_get_devdata(master); + platform_set_drvdata(pdev, hw); + + /* setup the state for the bitbang driver */ + hw->bitbang.master = master; + hw->bitbang.chipselect = altera_spi_chipsel; + hw->bitbang.txrx_bufs = altera_spi_txrx; + + /* find and map our resources */ + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + hw->base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(hw->base)) { + err = PTR_ERR(hw->base); + goto exit; + } + /* program defaults into the registers */ + hw->imr = 0; /* disable spi interrupts */ + writel(hw->imr, hw->base + ALTERA_SPI_CONTROL); + writel(0, hw->base + ALTERA_SPI_STATUS); /* clear status reg */ + if (readl(hw->base + ALTERA_SPI_STATUS) & ALTERA_SPI_STATUS_RRDY_MSK) + readl(hw->base + ALTERA_SPI_RXDATA); /* flush rxdata */ + /* irq is optional */ + hw->irq = platform_get_irq(pdev, 0); + if (hw->irq >= 0) { + init_completion(&hw->done); + err = devm_request_irq(&pdev->dev, hw->irq, altera_spi_irq, 0, + pdev->name, hw); + if (err) + goto exit; + } + + /* register our spi controller */ + err = spi_bitbang_start(&hw->bitbang); + if (err) + goto exit; + dev_info(&pdev->dev, "base %p, irq %d\n", hw->base, hw->irq); + + return 0; +exit: + spi_master_put(master); + return err; +} + +static int altera_spi_remove(struct platform_device *dev) +{ + struct altera_spi *hw = platform_get_drvdata(dev); + struct spi_master *master = hw->bitbang.master; + + spi_bitbang_stop(&hw->bitbang); + spi_master_put(master); + return 0; +} + +#ifdef CONFIG_OF +static const struct of_device_id altera_spi_match[] = { + { .compatible = "ALTR,spi-1.0", }, + { .compatible = "altr,spi-1.0", }, + {}, +}; +MODULE_DEVICE_TABLE(of, altera_spi_match); +#endif /* CONFIG_OF */ + +static struct platform_driver altera_spi_driver = { + .probe = altera_spi_probe, + .remove = altera_spi_remove, + .driver = { + .name = DRV_NAME, + .pm = NULL, + .of_match_table = of_match_ptr(altera_spi_match), + }, +}; +module_platform_driver(altera_spi_driver); + +MODULE_DESCRIPTION("Altera SPI driver"); +MODULE_AUTHOR("Thomas Chou <thomas@wytron.com.tw>"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:" DRV_NAME); diff --git a/drivers/spi/spi-ath79.c b/drivers/spi/spi-ath79.c new file mode 100644 index 000000000..b02eb4ac0 --- /dev/null +++ b/drivers/spi/spi-ath79.c @@ -0,0 +1,317 @@ +/* + * SPI controller driver for the Atheros AR71XX/AR724X/AR913X SoCs + * + * Copyright (C) 2009-2011 Gabor Juhos <juhosg@openwrt.org> + * + * This driver has been based on the spi-gpio.c: + * Copyright (C) 2006,2008 David Brownell + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/delay.h> +#include <linux/spinlock.h> +#include <linux/platform_device.h> +#include <linux/io.h> +#include <linux/spi/spi.h> +#include <linux/spi/spi_bitbang.h> +#include <linux/bitops.h> +#include <linux/gpio.h> +#include <linux/clk.h> +#include <linux/err.h> + +#include <asm/mach-ath79/ar71xx_regs.h> +#include <asm/mach-ath79/ath79_spi_platform.h> + +#define DRV_NAME "ath79-spi" + +#define ATH79_SPI_RRW_DELAY_FACTOR 12000 +#define MHZ (1000 * 1000) + +struct ath79_spi { + struct spi_bitbang bitbang; + u32 ioc_base; + u32 reg_ctrl; + void __iomem *base; + struct clk *clk; + unsigned rrw_delay; +}; + +static inline u32 ath79_spi_rr(struct ath79_spi *sp, unsigned reg) +{ + return ioread32(sp->base + reg); +} + +static inline void ath79_spi_wr(struct ath79_spi *sp, unsigned reg, u32 val) +{ + iowrite32(val, sp->base + reg); +} + +static inline struct ath79_spi *ath79_spidev_to_sp(struct spi_device *spi) +{ + return spi_master_get_devdata(spi->master); +} + +static inline void ath79_spi_delay(struct ath79_spi *sp, unsigned nsecs) +{ + if (nsecs > sp->rrw_delay) + ndelay(nsecs - sp->rrw_delay); +} + +static void ath79_spi_chipselect(struct spi_device *spi, int is_active) +{ + struct ath79_spi *sp = ath79_spidev_to_sp(spi); + int cs_high = (spi->mode & SPI_CS_HIGH) ? is_active : !is_active; + + if (is_active) { + /* set initial clock polarity */ + if (spi->mode & SPI_CPOL) + sp->ioc_base |= AR71XX_SPI_IOC_CLK; + else + sp->ioc_base &= ~AR71XX_SPI_IOC_CLK; + + ath79_spi_wr(sp, AR71XX_SPI_REG_IOC, sp->ioc_base); + } + + if (spi->chip_select) { + struct ath79_spi_controller_data *cdata = spi->controller_data; + + /* SPI is normally active-low */ + gpio_set_value(cdata->gpio, cs_high); + } else { + if (cs_high) + sp->ioc_base |= AR71XX_SPI_IOC_CS0; + else + sp->ioc_base &= ~AR71XX_SPI_IOC_CS0; + + ath79_spi_wr(sp, AR71XX_SPI_REG_IOC, sp->ioc_base); + } + +} + +static void ath79_spi_enable(struct ath79_spi *sp) +{ + /* enable GPIO mode */ + ath79_spi_wr(sp, AR71XX_SPI_REG_FS, AR71XX_SPI_FS_GPIO); + + /* save CTRL register */ + sp->reg_ctrl = ath79_spi_rr(sp, AR71XX_SPI_REG_CTRL); + sp->ioc_base = ath79_spi_rr(sp, AR71XX_SPI_REG_IOC); + + /* TODO: setup speed? */ + ath79_spi_wr(sp, AR71XX_SPI_REG_CTRL, 0x43); +} + +static void ath79_spi_disable(struct ath79_spi *sp) +{ + /* restore CTRL register */ + ath79_spi_wr(sp, AR71XX_SPI_REG_CTRL, sp->reg_ctrl); + /* disable GPIO mode */ + ath79_spi_wr(sp, AR71XX_SPI_REG_FS, 0); +} + +static int ath79_spi_setup_cs(struct spi_device *spi) +{ + struct ath79_spi_controller_data *cdata; + int status; + + cdata = spi->controller_data; + if (spi->chip_select && !cdata) + return -EINVAL; + + status = 0; + if (spi->chip_select) { + unsigned long flags; + + flags = GPIOF_DIR_OUT; + if (spi->mode & SPI_CS_HIGH) + flags |= GPIOF_INIT_LOW; + else + flags |= GPIOF_INIT_HIGH; + + status = gpio_request_one(cdata->gpio, flags, + dev_name(&spi->dev)); + } + + return status; +} + +static void ath79_spi_cleanup_cs(struct spi_device *spi) +{ + if (spi->chip_select) { + struct ath79_spi_controller_data *cdata = spi->controller_data; + gpio_free(cdata->gpio); + } +} + +static int ath79_spi_setup(struct spi_device *spi) +{ + int status = 0; + + if (!spi->controller_state) { + status = ath79_spi_setup_cs(spi); + if (status) + return status; + } + + status = spi_bitbang_setup(spi); + if (status && !spi->controller_state) + ath79_spi_cleanup_cs(spi); + + return status; +} + +static void ath79_spi_cleanup(struct spi_device *spi) +{ + ath79_spi_cleanup_cs(spi); + spi_bitbang_cleanup(spi); +} + +static u32 ath79_spi_txrx_mode0(struct spi_device *spi, unsigned nsecs, + u32 word, u8 bits) +{ + struct ath79_spi *sp = ath79_spidev_to_sp(spi); + u32 ioc = sp->ioc_base; + + /* clock starts at inactive polarity */ + for (word <<= (32 - bits); likely(bits); bits--) { + u32 out; + + if (word & (1 << 31)) + out = ioc | AR71XX_SPI_IOC_DO; + else + out = ioc & ~AR71XX_SPI_IOC_DO; + + /* setup MSB (to slave) on trailing edge */ + ath79_spi_wr(sp, AR71XX_SPI_REG_IOC, out); + ath79_spi_delay(sp, nsecs); + ath79_spi_wr(sp, AR71XX_SPI_REG_IOC, out | AR71XX_SPI_IOC_CLK); + ath79_spi_delay(sp, nsecs); + if (bits == 1) + ath79_spi_wr(sp, AR71XX_SPI_REG_IOC, out); + + word <<= 1; + } + + return ath79_spi_rr(sp, AR71XX_SPI_REG_RDS); +} + +static int ath79_spi_probe(struct platform_device *pdev) +{ + struct spi_master *master; + struct ath79_spi *sp; + struct ath79_spi_platform_data *pdata; + struct resource *r; + unsigned long rate; + int ret; + + master = spi_alloc_master(&pdev->dev, sizeof(*sp)); + if (master == NULL) { + dev_err(&pdev->dev, "failed to allocate spi master\n"); + return -ENOMEM; + } + + sp = spi_master_get_devdata(master); + platform_set_drvdata(pdev, sp); + + pdata = dev_get_platdata(&pdev->dev); + + master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32); + master->setup = ath79_spi_setup; + master->cleanup = ath79_spi_cleanup; + if (pdata) { + master->bus_num = pdata->bus_num; + master->num_chipselect = pdata->num_chipselect; + } + + sp->bitbang.master = master; + sp->bitbang.chipselect = ath79_spi_chipselect; + sp->bitbang.txrx_word[SPI_MODE_0] = ath79_spi_txrx_mode0; + sp->bitbang.setup_transfer = spi_bitbang_setup_transfer; + sp->bitbang.flags = SPI_CS_HIGH; + + r = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (r == NULL) { + ret = -ENOENT; + goto err_put_master; + } + + sp->base = devm_ioremap(&pdev->dev, r->start, resource_size(r)); + if (!sp->base) { + ret = -ENXIO; + goto err_put_master; + } + + sp->clk = devm_clk_get(&pdev->dev, "ahb"); + if (IS_ERR(sp->clk)) { + ret = PTR_ERR(sp->clk); + goto err_put_master; + } + + ret = clk_enable(sp->clk); + if (ret) + goto err_put_master; + + rate = DIV_ROUND_UP(clk_get_rate(sp->clk), MHZ); + if (!rate) { + ret = -EINVAL; + goto err_clk_disable; + } + + sp->rrw_delay = ATH79_SPI_RRW_DELAY_FACTOR / rate; + dev_dbg(&pdev->dev, "register read/write delay is %u nsecs\n", + sp->rrw_delay); + + ath79_spi_enable(sp); + ret = spi_bitbang_start(&sp->bitbang); + if (ret) + goto err_disable; + + return 0; + +err_disable: + ath79_spi_disable(sp); +err_clk_disable: + clk_disable(sp->clk); +err_put_master: + spi_master_put(sp->bitbang.master); + + return ret; +} + +static int ath79_spi_remove(struct platform_device *pdev) +{ + struct ath79_spi *sp = platform_get_drvdata(pdev); + + spi_bitbang_stop(&sp->bitbang); + ath79_spi_disable(sp); + clk_disable(sp->clk); + spi_master_put(sp->bitbang.master); + + return 0; +} + +static void ath79_spi_shutdown(struct platform_device *pdev) +{ + ath79_spi_remove(pdev); +} + +static struct platform_driver ath79_spi_driver = { + .probe = ath79_spi_probe, + .remove = ath79_spi_remove, + .shutdown = ath79_spi_shutdown, + .driver = { + .name = DRV_NAME, + }, +}; +module_platform_driver(ath79_spi_driver); + +MODULE_DESCRIPTION("SPI controller driver for Atheros AR71XX/AR724X/AR913X"); +MODULE_AUTHOR("Gabor Juhos <juhosg@openwrt.org>"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:" DRV_NAME); diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c new file mode 100644 index 000000000..a2f40b1b2 --- /dev/null +++ b/drivers/spi/spi-atmel.c @@ -0,0 +1,1540 @@ +/* + * Driver for Atmel AT32 and AT91 SPI Controllers + * + * Copyright (C) 2006 Atmel Corporation + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/kernel.h> +#include <linux/clk.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/delay.h> +#include <linux/dma-mapping.h> +#include <linux/dmaengine.h> +#include <linux/err.h> +#include <linux/interrupt.h> +#include <linux/spi/spi.h> +#include <linux/slab.h> +#include <linux/platform_data/atmel.h> +#include <linux/platform_data/dma-atmel.h> +#include <linux/of.h> + +#include <linux/io.h> +#include <linux/gpio.h> +#include <linux/pinctrl/consumer.h> +#include <linux/pm_runtime.h> + +/* SPI register offsets */ +#define SPI_CR 0x0000 +#define SPI_MR 0x0004 +#define SPI_RDR 0x0008 +#define SPI_TDR 0x000c +#define SPI_SR 0x0010 +#define SPI_IER 0x0014 +#define SPI_IDR 0x0018 +#define SPI_IMR 0x001c +#define SPI_CSR0 0x0030 +#define SPI_CSR1 0x0034 +#define SPI_CSR2 0x0038 +#define SPI_CSR3 0x003c +#define SPI_VERSION 0x00fc +#define SPI_RPR 0x0100 +#define SPI_RCR 0x0104 +#define SPI_TPR 0x0108 +#define SPI_TCR 0x010c +#define SPI_RNPR 0x0110 +#define SPI_RNCR 0x0114 +#define SPI_TNPR 0x0118 +#define SPI_TNCR 0x011c +#define SPI_PTCR 0x0120 +#define SPI_PTSR 0x0124 + +/* Bitfields in CR */ +#define SPI_SPIEN_OFFSET 0 +#define SPI_SPIEN_SIZE 1 +#define SPI_SPIDIS_OFFSET 1 +#define SPI_SPIDIS_SIZE 1 +#define SPI_SWRST_OFFSET 7 +#define SPI_SWRST_SIZE 1 +#define SPI_LASTXFER_OFFSET 24 +#define SPI_LASTXFER_SIZE 1 + +/* Bitfields in MR */ +#define SPI_MSTR_OFFSET 0 +#define SPI_MSTR_SIZE 1 +#define SPI_PS_OFFSET 1 +#define SPI_PS_SIZE 1 +#define SPI_PCSDEC_OFFSET 2 +#define SPI_PCSDEC_SIZE 1 +#define SPI_FDIV_OFFSET 3 +#define SPI_FDIV_SIZE 1 +#define SPI_MODFDIS_OFFSET 4 +#define SPI_MODFDIS_SIZE 1 +#define SPI_WDRBT_OFFSET 5 +#define SPI_WDRBT_SIZE 1 +#define SPI_LLB_OFFSET 7 +#define SPI_LLB_SIZE 1 +#define SPI_PCS_OFFSET 16 +#define SPI_PCS_SIZE 4 +#define SPI_DLYBCS_OFFSET 24 +#define SPI_DLYBCS_SIZE 8 + +/* Bitfields in RDR */ +#define SPI_RD_OFFSET 0 +#define SPI_RD_SIZE 16 + +/* Bitfields in TDR */ +#define SPI_TD_OFFSET 0 +#define SPI_TD_SIZE 16 + +/* Bitfields in SR */ +#define SPI_RDRF_OFFSET 0 +#define SPI_RDRF_SIZE 1 +#define SPI_TDRE_OFFSET 1 +#define SPI_TDRE_SIZE 1 +#define SPI_MODF_OFFSET 2 +#define SPI_MODF_SIZE 1 +#define SPI_OVRES_OFFSET 3 +#define SPI_OVRES_SIZE 1 +#define SPI_ENDRX_OFFSET 4 +#define SPI_ENDRX_SIZE 1 +#define SPI_ENDTX_OFFSET 5 +#define SPI_ENDTX_SIZE 1 +#define SPI_RXBUFF_OFFSET 6 +#define SPI_RXBUFF_SIZE 1 +#define SPI_TXBUFE_OFFSET 7 +#define SPI_TXBUFE_SIZE 1 +#define SPI_NSSR_OFFSET 8 +#define SPI_NSSR_SIZE 1 +#define SPI_TXEMPTY_OFFSET 9 +#define SPI_TXEMPTY_SIZE 1 +#define SPI_SPIENS_OFFSET 16 +#define SPI_SPIENS_SIZE 1 + +/* Bitfields in CSR0 */ +#define SPI_CPOL_OFFSET 0 +#define SPI_CPOL_SIZE 1 +#define SPI_NCPHA_OFFSET 1 +#define SPI_NCPHA_SIZE 1 +#define SPI_CSAAT_OFFSET 3 +#define SPI_CSAAT_SIZE 1 +#define SPI_BITS_OFFSET 4 +#define SPI_BITS_SIZE 4 +#define SPI_SCBR_OFFSET 8 +#define SPI_SCBR_SIZE 8 +#define SPI_DLYBS_OFFSET 16 +#define SPI_DLYBS_SIZE 8 +#define SPI_DLYBCT_OFFSET 24 +#define SPI_DLYBCT_SIZE 8 + +/* Bitfields in RCR */ +#define SPI_RXCTR_OFFSET 0 +#define SPI_RXCTR_SIZE 16 + +/* Bitfields in TCR */ +#define SPI_TXCTR_OFFSET 0 +#define SPI_TXCTR_SIZE 16 + +/* Bitfields in RNCR */ +#define SPI_RXNCR_OFFSET 0 +#define SPI_RXNCR_SIZE 16 + +/* Bitfields in TNCR */ +#define SPI_TXNCR_OFFSET 0 +#define SPI_TXNCR_SIZE 16 + +/* Bitfields in PTCR */ +#define SPI_RXTEN_OFFSET 0 +#define SPI_RXTEN_SIZE 1 +#define SPI_RXTDIS_OFFSET 1 +#define SPI_RXTDIS_SIZE 1 +#define SPI_TXTEN_OFFSET 8 +#define SPI_TXTEN_SIZE 1 +#define SPI_TXTDIS_OFFSET 9 +#define SPI_TXTDIS_SIZE 1 + +/* Constants for BITS */ +#define SPI_BITS_8_BPT 0 +#define SPI_BITS_9_BPT 1 +#define SPI_BITS_10_BPT 2 +#define SPI_BITS_11_BPT 3 +#define SPI_BITS_12_BPT 4 +#define SPI_BITS_13_BPT 5 +#define SPI_BITS_14_BPT 6 +#define SPI_BITS_15_BPT 7 +#define SPI_BITS_16_BPT 8 + +/* Bit manipulation macros */ +#define SPI_BIT(name) \ + (1 << SPI_##name##_OFFSET) +#define SPI_BF(name, value) \ + (((value) & ((1 << SPI_##name##_SIZE) - 1)) << SPI_##name##_OFFSET) +#define SPI_BFEXT(name, value) \ + (((value) >> SPI_##name##_OFFSET) & ((1 << SPI_##name##_SIZE) - 1)) +#define SPI_BFINS(name, value, old) \ + (((old) & ~(((1 << SPI_##name##_SIZE) - 1) << SPI_##name##_OFFSET)) \ + | SPI_BF(name, value)) + +/* Register access macros */ +#ifdef CONFIG_AVR32 +#define spi_readl(port, reg) \ + __raw_readl((port)->regs + SPI_##reg) +#define spi_writel(port, reg, value) \ + __raw_writel((value), (port)->regs + SPI_##reg) +#else +#define spi_readl(port, reg) \ + readl_relaxed((port)->regs + SPI_##reg) +#define spi_writel(port, reg, value) \ + writel_relaxed((value), (port)->regs + SPI_##reg) +#endif +/* use PIO for small transfers, avoiding DMA setup/teardown overhead and + * cache operations; better heuristics consider wordsize and bitrate. + */ +#define DMA_MIN_BYTES 16 + +#define SPI_DMA_TIMEOUT (msecs_to_jiffies(1000)) + +#define AUTOSUSPEND_TIMEOUT 2000 + +struct atmel_spi_dma { + struct dma_chan *chan_rx; + struct dma_chan *chan_tx; + struct scatterlist sgrx; + struct scatterlist sgtx; + struct dma_async_tx_descriptor *data_desc_rx; + struct dma_async_tx_descriptor *data_desc_tx; + + struct at_dma_slave dma_slave; +}; + +struct atmel_spi_caps { + bool is_spi2; + bool has_wdrbt; + bool has_dma_support; +}; + +/* + * The core SPI transfer engine just talks to a register bank to set up + * DMA transfers; transfer queue progress is driven by IRQs. The clock + * framework provides the base clock, subdivided for each spi_device. + */ +struct atmel_spi { + spinlock_t lock; + unsigned long flags; + + phys_addr_t phybase; + void __iomem *regs; + int irq; + struct clk *clk; + struct platform_device *pdev; + + struct spi_transfer *current_transfer; + int current_remaining_bytes; + int done_status; + + struct completion xfer_completion; + + /* scratch buffer */ + void *buffer; + dma_addr_t buffer_dma; + + struct atmel_spi_caps caps; + + bool use_dma; + bool use_pdc; + /* dmaengine data */ + struct atmel_spi_dma dma; + + bool keep_cs; + bool cs_active; +}; + +/* Controller-specific per-slave state */ +struct atmel_spi_device { + unsigned int npcs_pin; + u32 csr; +}; + +#define BUFFER_SIZE PAGE_SIZE +#define INVALID_DMA_ADDRESS 0xffffffff + +/* + * Version 2 of the SPI controller has + * - CR.LASTXFER + * - SPI_MR.DIV32 may become FDIV or must-be-zero (here: always zero) + * - SPI_SR.TXEMPTY, SPI_SR.NSSR (and corresponding irqs) + * - SPI_CSRx.CSAAT + * - SPI_CSRx.SBCR allows faster clocking + */ +static bool atmel_spi_is_v2(struct atmel_spi *as) +{ + return as->caps.is_spi2; +} + +/* + * Earlier SPI controllers (e.g. on at91rm9200) have a design bug whereby + * they assume that spi slave device state will not change on deselect, so + * that automagic deselection is OK. ("NPCSx rises if no data is to be + * transmitted") Not so! Workaround uses nCSx pins as GPIOs; or newer + * controllers have CSAAT and friends. + * + * Since the CSAAT functionality is a bit weird on newer controllers as + * well, we use GPIO to control nCSx pins on all controllers, updating + * MR.PCS to avoid confusing the controller. Using GPIOs also lets us + * support active-high chipselects despite the controller's belief that + * only active-low devices/systems exists. + * + * However, at91rm9200 has a second erratum whereby nCS0 doesn't work + * right when driven with GPIO. ("Mode Fault does not allow more than one + * Master on Chip Select 0.") No workaround exists for that ... so for + * nCS0 on that chip, we (a) don't use the GPIO, (b) can't support CS_HIGH, + * and (c) will trigger that first erratum in some cases. + */ + +static void cs_activate(struct atmel_spi *as, struct spi_device *spi) +{ + struct atmel_spi_device *asd = spi->controller_state; + unsigned active = spi->mode & SPI_CS_HIGH; + u32 mr; + + if (atmel_spi_is_v2(as)) { + spi_writel(as, CSR0 + 4 * spi->chip_select, asd->csr); + /* For the low SPI version, there is a issue that PDC transfer + * on CS1,2,3 needs SPI_CSR0.BITS config as SPI_CSR1,2,3.BITS + */ + spi_writel(as, CSR0, asd->csr); + if (as->caps.has_wdrbt) { + spi_writel(as, MR, + SPI_BF(PCS, ~(0x01 << spi->chip_select)) + | SPI_BIT(WDRBT) + | SPI_BIT(MODFDIS) + | SPI_BIT(MSTR)); + } else { + spi_writel(as, MR, + SPI_BF(PCS, ~(0x01 << spi->chip_select)) + | SPI_BIT(MODFDIS) + | SPI_BIT(MSTR)); + } + + mr = spi_readl(as, MR); + gpio_set_value(asd->npcs_pin, active); + } else { + u32 cpol = (spi->mode & SPI_CPOL) ? SPI_BIT(CPOL) : 0; + int i; + u32 csr; + + /* Make sure clock polarity is correct */ + for (i = 0; i < spi->master->num_chipselect; i++) { + csr = spi_readl(as, CSR0 + 4 * i); + if ((csr ^ cpol) & SPI_BIT(CPOL)) + spi_writel(as, CSR0 + 4 * i, + csr ^ SPI_BIT(CPOL)); + } + + mr = spi_readl(as, MR); + mr = SPI_BFINS(PCS, ~(1 << spi->chip_select), mr); + if (spi->chip_select != 0) + gpio_set_value(asd->npcs_pin, active); + spi_writel(as, MR, mr); + } + + dev_dbg(&spi->dev, "activate %u%s, mr %08x\n", + asd->npcs_pin, active ? " (high)" : "", + mr); +} + +static void cs_deactivate(struct atmel_spi *as, struct spi_device *spi) +{ + struct atmel_spi_device *asd = spi->controller_state; + unsigned active = spi->mode & SPI_CS_HIGH; + u32 mr; + + /* only deactivate *this* device; sometimes transfers to + * another device may be active when this routine is called. + */ + mr = spi_readl(as, MR); + if (~SPI_BFEXT(PCS, mr) & (1 << spi->chip_select)) { + mr = SPI_BFINS(PCS, 0xf, mr); + spi_writel(as, MR, mr); + } + + dev_dbg(&spi->dev, "DEactivate %u%s, mr %08x\n", + asd->npcs_pin, active ? " (low)" : "", + mr); + + if (atmel_spi_is_v2(as) || spi->chip_select != 0) + gpio_set_value(asd->npcs_pin, !active); +} + +static void atmel_spi_lock(struct atmel_spi *as) __acquires(&as->lock) +{ + spin_lock_irqsave(&as->lock, as->flags); +} + +static void atmel_spi_unlock(struct atmel_spi *as) __releases(&as->lock) +{ + spin_unlock_irqrestore(&as->lock, as->flags); +} + +static inline bool atmel_spi_use_dma(struct atmel_spi *as, + struct spi_transfer *xfer) +{ + return as->use_dma && xfer->len >= DMA_MIN_BYTES; +} + +static int atmel_spi_dma_slave_config(struct atmel_spi *as, + struct dma_slave_config *slave_config, + u8 bits_per_word) +{ + int err = 0; + + if (bits_per_word > 8) { + slave_config->dst_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES; + slave_config->src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES; + } else { + slave_config->dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; + slave_config->src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; + } + + slave_config->dst_addr = (dma_addr_t)as->phybase + SPI_TDR; + slave_config->src_addr = (dma_addr_t)as->phybase + SPI_RDR; + slave_config->src_maxburst = 1; + slave_config->dst_maxburst = 1; + slave_config->device_fc = false; + + slave_config->direction = DMA_MEM_TO_DEV; + if (dmaengine_slave_config(as->dma.chan_tx, slave_config)) { + dev_err(&as->pdev->dev, + "failed to configure tx dma channel\n"); + err = -EINVAL; + } + + slave_config->direction = DMA_DEV_TO_MEM; + if (dmaengine_slave_config(as->dma.chan_rx, slave_config)) { + dev_err(&as->pdev->dev, + "failed to configure rx dma channel\n"); + err = -EINVAL; + } + + return err; +} + +static int atmel_spi_configure_dma(struct atmel_spi *as) +{ + struct dma_slave_config slave_config; + struct device *dev = &as->pdev->dev; + int err; + + dma_cap_mask_t mask; + dma_cap_zero(mask); + dma_cap_set(DMA_SLAVE, mask); + + as->dma.chan_tx = dma_request_slave_channel_reason(dev, "tx"); + if (IS_ERR(as->dma.chan_tx)) { + err = PTR_ERR(as->dma.chan_tx); + if (err == -EPROBE_DEFER) { + dev_warn(dev, "no DMA channel available at the moment\n"); + return err; + } + dev_err(dev, + "DMA TX channel not available, SPI unable to use DMA\n"); + err = -EBUSY; + goto error; + } + + /* + * No reason to check EPROBE_DEFER here since we have already requested + * tx channel. If it fails here, it's for another reason. + */ + as->dma.chan_rx = dma_request_slave_channel(dev, "rx"); + + if (!as->dma.chan_rx) { + dev_err(dev, + "DMA RX channel not available, SPI unable to use DMA\n"); + err = -EBUSY; + goto error; + } + + err = atmel_spi_dma_slave_config(as, &slave_config, 8); + if (err) + goto error; + + dev_info(&as->pdev->dev, + "Using %s (tx) and %s (rx) for DMA transfers\n", + dma_chan_name(as->dma.chan_tx), + dma_chan_name(as->dma.chan_rx)); + return 0; +error: + if (as->dma.chan_rx) + dma_release_channel(as->dma.chan_rx); + if (!IS_ERR(as->dma.chan_tx)) + dma_release_channel(as->dma.chan_tx); + return err; +} + +static void atmel_spi_stop_dma(struct atmel_spi *as) +{ + if (as->dma.chan_rx) + dmaengine_terminate_all(as->dma.chan_rx); + if (as->dma.chan_tx) + dmaengine_terminate_all(as->dma.chan_tx); +} + +static void atmel_spi_release_dma(struct atmel_spi *as) +{ + if (as->dma.chan_rx) + dma_release_channel(as->dma.chan_rx); + if (as->dma.chan_tx) + dma_release_channel(as->dma.chan_tx); +} + +/* This function is called by the DMA driver from tasklet context */ +static void dma_callback(void *data) +{ + struct spi_master *master = data; + struct atmel_spi *as = spi_master_get_devdata(master); + + complete(&as->xfer_completion); +} + +/* + * Next transfer using PIO. + */ +static void atmel_spi_next_xfer_pio(struct spi_master *master, + struct spi_transfer *xfer) +{ + struct atmel_spi *as = spi_master_get_devdata(master); + unsigned long xfer_pos = xfer->len - as->current_remaining_bytes; + + dev_vdbg(master->dev.parent, "atmel_spi_next_xfer_pio\n"); + + /* Make sure data is not remaining in RDR */ + spi_readl(as, RDR); + while (spi_readl(as, SR) & SPI_BIT(RDRF)) { + spi_readl(as, RDR); + cpu_relax(); + } + + if (xfer->tx_buf) { + if (xfer->bits_per_word > 8) + spi_writel(as, TDR, *(u16 *)(xfer->tx_buf + xfer_pos)); + else + spi_writel(as, TDR, *(u8 *)(xfer->tx_buf + xfer_pos)); + } else { + spi_writel(as, TDR, 0); + } + + dev_dbg(master->dev.parent, + " start pio xfer %p: len %u tx %p rx %p bitpw %d\n", + xfer, xfer->len, xfer->tx_buf, xfer->rx_buf, + xfer->bits_per_word); + + /* Enable relevant interrupts */ + spi_writel(as, IER, SPI_BIT(RDRF) | SPI_BIT(OVRES)); +} + +/* + * Submit next transfer for DMA. + */ +static int atmel_spi_next_xfer_dma_submit(struct spi_master *master, + struct spi_transfer *xfer, + u32 *plen) +{ + struct atmel_spi *as = spi_master_get_devdata(master); + struct dma_chan *rxchan = as->dma.chan_rx; + struct dma_chan *txchan = as->dma.chan_tx; + struct dma_async_tx_descriptor *rxdesc; + struct dma_async_tx_descriptor *txdesc; + struct dma_slave_config slave_config; + dma_cookie_t cookie; + u32 len = *plen; + + dev_vdbg(master->dev.parent, "atmel_spi_next_xfer_dma_submit\n"); + + /* Check that the channels are available */ + if (!rxchan || !txchan) + return -ENODEV; + + /* release lock for DMA operations */ + atmel_spi_unlock(as); + + /* prepare the RX dma transfer */ + sg_init_table(&as->dma.sgrx, 1); + if (xfer->rx_buf) { + as->dma.sgrx.dma_address = xfer->rx_dma + xfer->len - *plen; + } else { + as->dma.sgrx.dma_address = as->buffer_dma; + if (len > BUFFER_SIZE) + len = BUFFER_SIZE; + } + + /* prepare the TX dma transfer */ + sg_init_table(&as->dma.sgtx, 1); + if (xfer->tx_buf) { + as->dma.sgtx.dma_address = xfer->tx_dma + xfer->len - *plen; + } else { + as->dma.sgtx.dma_address = as->buffer_dma; + if (len > BUFFER_SIZE) + len = BUFFER_SIZE; + memset(as->buffer, 0, len); + } + + sg_dma_len(&as->dma.sgtx) = len; + sg_dma_len(&as->dma.sgrx) = len; + + *plen = len; + + if (atmel_spi_dma_slave_config(as, &slave_config, 8)) + goto err_exit; + + /* Send both scatterlists */ + rxdesc = dmaengine_prep_slave_sg(rxchan, &as->dma.sgrx, 1, + DMA_FROM_DEVICE, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + if (!rxdesc) + goto err_dma; + + txdesc = dmaengine_prep_slave_sg(txchan, &as->dma.sgtx, 1, + DMA_TO_DEVICE, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + if (!txdesc) + goto err_dma; + + dev_dbg(master->dev.parent, + " start dma xfer %p: len %u tx %p/%08llx rx %p/%08llx\n", + xfer, xfer->len, xfer->tx_buf, (unsigned long long)xfer->tx_dma, + xfer->rx_buf, (unsigned long long)xfer->rx_dma); + + /* Enable relevant interrupts */ + spi_writel(as, IER, SPI_BIT(OVRES)); + + /* Put the callback on the RX transfer only, that should finish last */ + rxdesc->callback = dma_callback; + rxdesc->callback_param = master; + + /* Submit and fire RX and TX with TX last so we're ready to read! */ + cookie = rxdesc->tx_submit(rxdesc); + if (dma_submit_error(cookie)) + goto err_dma; + cookie = txdesc->tx_submit(txdesc); + if (dma_submit_error(cookie)) + goto err_dma; + rxchan->device->device_issue_pending(rxchan); + txchan->device->device_issue_pending(txchan); + + /* take back lock */ + atmel_spi_lock(as); + return 0; + +err_dma: + spi_writel(as, IDR, SPI_BIT(OVRES)); + atmel_spi_stop_dma(as); +err_exit: + atmel_spi_lock(as); + return -ENOMEM; +} + +static void atmel_spi_next_xfer_data(struct spi_master *master, + struct spi_transfer *xfer, + dma_addr_t *tx_dma, + dma_addr_t *rx_dma, + u32 *plen) +{ + struct atmel_spi *as = spi_master_get_devdata(master); + u32 len = *plen; + + /* use scratch buffer only when rx or tx data is unspecified */ + if (xfer->rx_buf) + *rx_dma = xfer->rx_dma + xfer->len - *plen; + else { + *rx_dma = as->buffer_dma; + if (len > BUFFER_SIZE) + len = BUFFER_SIZE; + } + + if (xfer->tx_buf) + *tx_dma = xfer->tx_dma + xfer->len - *plen; + else { + *tx_dma = as->buffer_dma; + if (len > BUFFER_SIZE) + len = BUFFER_SIZE; + memset(as->buffer, 0, len); + dma_sync_single_for_device(&as->pdev->dev, + as->buffer_dma, len, DMA_TO_DEVICE); + } + + *plen = len; +} + +static int atmel_spi_set_xfer_speed(struct atmel_spi *as, + struct spi_device *spi, + struct spi_transfer *xfer) +{ + u32 scbr, csr; + unsigned long bus_hz; + + /* v1 chips start out at half the peripheral bus speed. */ + bus_hz = clk_get_rate(as->clk); + if (!atmel_spi_is_v2(as)) + bus_hz /= 2; + + /* + * Calculate the lowest divider that satisfies the + * constraint, assuming div32/fdiv/mbz == 0. + */ + if (xfer->speed_hz) + scbr = DIV_ROUND_UP(bus_hz, xfer->speed_hz); + else + /* + * This can happend if max_speed is null. + * In this case, we set the lowest possible speed + */ + scbr = 0xff; + + /* + * If the resulting divider doesn't fit into the + * register bitfield, we can't satisfy the constraint. + */ + if (scbr >= (1 << SPI_SCBR_SIZE)) { + dev_err(&spi->dev, + "setup: %d Hz too slow, scbr %u; min %ld Hz\n", + xfer->speed_hz, scbr, bus_hz/255); + return -EINVAL; + } + if (scbr == 0) { + dev_err(&spi->dev, + "setup: %d Hz too high, scbr %u; max %ld Hz\n", + xfer->speed_hz, scbr, bus_hz); + return -EINVAL; + } + csr = spi_readl(as, CSR0 + 4 * spi->chip_select); + csr = SPI_BFINS(SCBR, scbr, csr); + spi_writel(as, CSR0 + 4 * spi->chip_select, csr); + + return 0; +} + +/* + * Submit next transfer for PDC. + * lock is held, spi irq is blocked + */ +static void atmel_spi_pdc_next_xfer(struct spi_master *master, + struct spi_message *msg, + struct spi_transfer *xfer) +{ + struct atmel_spi *as = spi_master_get_devdata(master); + u32 len; + dma_addr_t tx_dma, rx_dma; + + spi_writel(as, PTCR, SPI_BIT(RXTDIS) | SPI_BIT(TXTDIS)); + + len = as->current_remaining_bytes; + atmel_spi_next_xfer_data(master, xfer, &tx_dma, &rx_dma, &len); + as->current_remaining_bytes -= len; + + spi_writel(as, RPR, rx_dma); + spi_writel(as, TPR, tx_dma); + + if (msg->spi->bits_per_word > 8) + len >>= 1; + spi_writel(as, RCR, len); + spi_writel(as, TCR, len); + + dev_dbg(&msg->spi->dev, + " start xfer %p: len %u tx %p/%08llx rx %p/%08llx\n", + xfer, xfer->len, xfer->tx_buf, + (unsigned long long)xfer->tx_dma, xfer->rx_buf, + (unsigned long long)xfer->rx_dma); + + if (as->current_remaining_bytes) { + len = as->current_remaining_bytes; + atmel_spi_next_xfer_data(master, xfer, &tx_dma, &rx_dma, &len); + as->current_remaining_bytes -= len; + + spi_writel(as, RNPR, rx_dma); + spi_writel(as, TNPR, tx_dma); + + if (msg->spi->bits_per_word > 8) + len >>= 1; + spi_writel(as, RNCR, len); + spi_writel(as, TNCR, len); + + dev_dbg(&msg->spi->dev, + " next xfer %p: len %u tx %p/%08llx rx %p/%08llx\n", + xfer, xfer->len, xfer->tx_buf, + (unsigned long long)xfer->tx_dma, xfer->rx_buf, + (unsigned long long)xfer->rx_dma); + } + + /* REVISIT: We're waiting for RXBUFF before we start the next + * transfer because we need to handle some difficult timing + * issues otherwise. If we wait for TXBUFE in one transfer and + * then starts waiting for RXBUFF in the next, it's difficult + * to tell the difference between the RXBUFF interrupt we're + * actually waiting for and the RXBUFF interrupt of the + * previous transfer. + * + * It should be doable, though. Just not now... + */ + spi_writel(as, IER, SPI_BIT(RXBUFF) | SPI_BIT(OVRES)); + spi_writel(as, PTCR, SPI_BIT(TXTEN) | SPI_BIT(RXTEN)); +} + +/* + * For DMA, tx_buf/tx_dma have the same relationship as rx_buf/rx_dma: + * - The buffer is either valid for CPU access, else NULL + * - If the buffer is valid, so is its DMA address + * + * This driver manages the dma address unless message->is_dma_mapped. + */ +static int +atmel_spi_dma_map_xfer(struct atmel_spi *as, struct spi_transfer *xfer) +{ + struct device *dev = &as->pdev->dev; + + xfer->tx_dma = xfer->rx_dma = INVALID_DMA_ADDRESS; + if (xfer->tx_buf) { + /* tx_buf is a const void* where we need a void * for the dma + * mapping */ + void *nonconst_tx = (void *)xfer->tx_buf; + + xfer->tx_dma = dma_map_single(dev, + nonconst_tx, xfer->len, + DMA_TO_DEVICE); + if (dma_mapping_error(dev, xfer->tx_dma)) + return -ENOMEM; + } + if (xfer->rx_buf) { + xfer->rx_dma = dma_map_single(dev, + xfer->rx_buf, xfer->len, + DMA_FROM_DEVICE); + if (dma_mapping_error(dev, xfer->rx_dma)) { + if (xfer->tx_buf) + dma_unmap_single(dev, + xfer->tx_dma, xfer->len, + DMA_TO_DEVICE); + return -ENOMEM; + } + } + return 0; +} + +static void atmel_spi_dma_unmap_xfer(struct spi_master *master, + struct spi_transfer *xfer) +{ + if (xfer->tx_dma != INVALID_DMA_ADDRESS) + dma_unmap_single(master->dev.parent, xfer->tx_dma, + xfer->len, DMA_TO_DEVICE); + if (xfer->rx_dma != INVALID_DMA_ADDRESS) + dma_unmap_single(master->dev.parent, xfer->rx_dma, + xfer->len, DMA_FROM_DEVICE); +} + +static void atmel_spi_disable_pdc_transfer(struct atmel_spi *as) +{ + spi_writel(as, PTCR, SPI_BIT(RXTDIS) | SPI_BIT(TXTDIS)); +} + +/* Called from IRQ + * + * Must update "current_remaining_bytes" to keep track of data + * to transfer. + */ +static void +atmel_spi_pump_pio_data(struct atmel_spi *as, struct spi_transfer *xfer) +{ + u8 *rxp; + u16 *rxp16; + unsigned long xfer_pos = xfer->len - as->current_remaining_bytes; + + if (xfer->rx_buf) { + if (xfer->bits_per_word > 8) { + rxp16 = (u16 *)(((u8 *)xfer->rx_buf) + xfer_pos); + *rxp16 = spi_readl(as, RDR); + } else { + rxp = ((u8 *)xfer->rx_buf) + xfer_pos; + *rxp = spi_readl(as, RDR); + } + } else { + spi_readl(as, RDR); + } + if (xfer->bits_per_word > 8) { + if (as->current_remaining_bytes > 2) + as->current_remaining_bytes -= 2; + else + as->current_remaining_bytes = 0; + } else { + as->current_remaining_bytes--; + } +} + +/* Interrupt + * + * No need for locking in this Interrupt handler: done_status is the + * only information modified. + */ +static irqreturn_t +atmel_spi_pio_interrupt(int irq, void *dev_id) +{ + struct spi_master *master = dev_id; + struct atmel_spi *as = spi_master_get_devdata(master); + u32 status, pending, imr; + struct spi_transfer *xfer; + int ret = IRQ_NONE; + + imr = spi_readl(as, IMR); + status = spi_readl(as, SR); + pending = status & imr; + + if (pending & SPI_BIT(OVRES)) { + ret = IRQ_HANDLED; + spi_writel(as, IDR, SPI_BIT(OVRES)); + dev_warn(master->dev.parent, "overrun\n"); + + /* + * When we get an overrun, we disregard the current + * transfer. Data will not be copied back from any + * bounce buffer and msg->actual_len will not be + * updated with the last xfer. + * + * We will also not process any remaning transfers in + * the message. + */ + as->done_status = -EIO; + smp_wmb(); + + /* Clear any overrun happening while cleaning up */ + spi_readl(as, SR); + + complete(&as->xfer_completion); + + } else if (pending & SPI_BIT(RDRF)) { + atmel_spi_lock(as); + + if (as->current_remaining_bytes) { + ret = IRQ_HANDLED; + xfer = as->current_transfer; + atmel_spi_pump_pio_data(as, xfer); + if (!as->current_remaining_bytes) + spi_writel(as, IDR, pending); + + complete(&as->xfer_completion); + } + + atmel_spi_unlock(as); + } else { + WARN_ONCE(pending, "IRQ not handled, pending = %x\n", pending); + ret = IRQ_HANDLED; + spi_writel(as, IDR, pending); + } + + return ret; +} + +static irqreturn_t +atmel_spi_pdc_interrupt(int irq, void *dev_id) +{ + struct spi_master *master = dev_id; + struct atmel_spi *as = spi_master_get_devdata(master); + u32 status, pending, imr; + int ret = IRQ_NONE; + + imr = spi_readl(as, IMR); + status = spi_readl(as, SR); + pending = status & imr; + + if (pending & SPI_BIT(OVRES)) { + + ret = IRQ_HANDLED; + + spi_writel(as, IDR, (SPI_BIT(RXBUFF) | SPI_BIT(ENDRX) + | SPI_BIT(OVRES))); + + /* Clear any overrun happening while cleaning up */ + spi_readl(as, SR); + + as->done_status = -EIO; + + complete(&as->xfer_completion); + + } else if (pending & (SPI_BIT(RXBUFF) | SPI_BIT(ENDRX))) { + ret = IRQ_HANDLED; + + spi_writel(as, IDR, pending); + + complete(&as->xfer_completion); + } + + return ret; +} + +static int atmel_spi_setup(struct spi_device *spi) +{ + struct atmel_spi *as; + struct atmel_spi_device *asd; + u32 csr; + unsigned int bits = spi->bits_per_word; + unsigned int npcs_pin; + int ret; + + as = spi_master_get_devdata(spi->master); + + /* see notes above re chipselect */ + if (!atmel_spi_is_v2(as) + && spi->chip_select == 0 + && (spi->mode & SPI_CS_HIGH)) { + dev_dbg(&spi->dev, "setup: can't be active-high\n"); + return -EINVAL; + } + + csr = SPI_BF(BITS, bits - 8); + if (spi->mode & SPI_CPOL) + csr |= SPI_BIT(CPOL); + if (!(spi->mode & SPI_CPHA)) + csr |= SPI_BIT(NCPHA); + + /* DLYBS is mostly irrelevant since we manage chipselect using GPIOs. + * + * DLYBCT would add delays between words, slowing down transfers. + * It could potentially be useful to cope with DMA bottlenecks, but + * in those cases it's probably best to just use a lower bitrate. + */ + csr |= SPI_BF(DLYBS, 0); + csr |= SPI_BF(DLYBCT, 0); + + /* chipselect must have been muxed as GPIO (e.g. in board setup) */ + npcs_pin = (unsigned long)spi->controller_data; + + if (gpio_is_valid(spi->cs_gpio)) + npcs_pin = spi->cs_gpio; + + asd = spi->controller_state; + if (!asd) { + asd = kzalloc(sizeof(struct atmel_spi_device), GFP_KERNEL); + if (!asd) + return -ENOMEM; + + ret = gpio_request(npcs_pin, dev_name(&spi->dev)); + if (ret) { + kfree(asd); + return ret; + } + + asd->npcs_pin = npcs_pin; + spi->controller_state = asd; + gpio_direction_output(npcs_pin, !(spi->mode & SPI_CS_HIGH)); + } + + asd->csr = csr; + + dev_dbg(&spi->dev, + "setup: bpw %u mode 0x%x -> csr%d %08x\n", + bits, spi->mode, spi->chip_select, csr); + + if (!atmel_spi_is_v2(as)) + spi_writel(as, CSR0 + 4 * spi->chip_select, csr); + + return 0; +} + +static int atmel_spi_one_transfer(struct spi_master *master, + struct spi_message *msg, + struct spi_transfer *xfer) +{ + struct atmel_spi *as; + struct spi_device *spi = msg->spi; + u8 bits; + u32 len; + struct atmel_spi_device *asd; + int timeout; + int ret; + unsigned long dma_timeout; + + as = spi_master_get_devdata(master); + + if (!(xfer->tx_buf || xfer->rx_buf) && xfer->len) { + dev_dbg(&spi->dev, "missing rx or tx buf\n"); + return -EINVAL; + } + + if (xfer->bits_per_word) { + asd = spi->controller_state; + bits = (asd->csr >> 4) & 0xf; + if (bits != xfer->bits_per_word - 8) { + dev_dbg(&spi->dev, + "you can't yet change bits_per_word in transfers\n"); + return -ENOPROTOOPT; + } + } + + /* + * DMA map early, for performance (empties dcache ASAP) and + * better fault reporting. + */ + if ((!msg->is_dma_mapped) + && (atmel_spi_use_dma(as, xfer) || as->use_pdc)) { + if (atmel_spi_dma_map_xfer(as, xfer) < 0) + return -ENOMEM; + } + + atmel_spi_set_xfer_speed(as, msg->spi, xfer); + + as->done_status = 0; + as->current_transfer = xfer; + as->current_remaining_bytes = xfer->len; + while (as->current_remaining_bytes) { + reinit_completion(&as->xfer_completion); + + if (as->use_pdc) { + atmel_spi_pdc_next_xfer(master, msg, xfer); + } else if (atmel_spi_use_dma(as, xfer)) { + len = as->current_remaining_bytes; + ret = atmel_spi_next_xfer_dma_submit(master, + xfer, &len); + if (ret) { + dev_err(&spi->dev, + "unable to use DMA, fallback to PIO\n"); + atmel_spi_next_xfer_pio(master, xfer); + } else { + as->current_remaining_bytes -= len; + if (as->current_remaining_bytes < 0) + as->current_remaining_bytes = 0; + } + } else { + atmel_spi_next_xfer_pio(master, xfer); + } + + /* interrupts are disabled, so free the lock for schedule */ + atmel_spi_unlock(as); + dma_timeout = wait_for_completion_timeout(&as->xfer_completion, + SPI_DMA_TIMEOUT); + atmel_spi_lock(as); + if (WARN_ON(dma_timeout == 0)) { + dev_err(&spi->dev, "spi transfer timeout\n"); + as->done_status = -EIO; + } + + if (as->done_status) + break; + } + + if (as->done_status) { + if (as->use_pdc) { + dev_warn(master->dev.parent, + "overrun (%u/%u remaining)\n", + spi_readl(as, TCR), spi_readl(as, RCR)); + + /* + * Clean up DMA registers and make sure the data + * registers are empty. + */ + spi_writel(as, RNCR, 0); + spi_writel(as, TNCR, 0); + spi_writel(as, RCR, 0); + spi_writel(as, TCR, 0); + for (timeout = 1000; timeout; timeout--) + if (spi_readl(as, SR) & SPI_BIT(TXEMPTY)) + break; + if (!timeout) + dev_warn(master->dev.parent, + "timeout waiting for TXEMPTY"); + while (spi_readl(as, SR) & SPI_BIT(RDRF)) + spi_readl(as, RDR); + + /* Clear any overrun happening while cleaning up */ + spi_readl(as, SR); + + } else if (atmel_spi_use_dma(as, xfer)) { + atmel_spi_stop_dma(as); + } + + if (!msg->is_dma_mapped + && (atmel_spi_use_dma(as, xfer) || as->use_pdc)) + atmel_spi_dma_unmap_xfer(master, xfer); + + return 0; + + } else { + /* only update length if no error */ + msg->actual_length += xfer->len; + } + + if (!msg->is_dma_mapped + && (atmel_spi_use_dma(as, xfer) || as->use_pdc)) + atmel_spi_dma_unmap_xfer(master, xfer); + + if (xfer->delay_usecs) + udelay(xfer->delay_usecs); + + if (xfer->cs_change) { + if (list_is_last(&xfer->transfer_list, + &msg->transfers)) { + as->keep_cs = true; + } else { + as->cs_active = !as->cs_active; + if (as->cs_active) + cs_activate(as, msg->spi); + else + cs_deactivate(as, msg->spi); + } + } + + return 0; +} + +static int atmel_spi_transfer_one_message(struct spi_master *master, + struct spi_message *msg) +{ + struct atmel_spi *as; + struct spi_transfer *xfer; + struct spi_device *spi = msg->spi; + int ret = 0; + + as = spi_master_get_devdata(master); + + dev_dbg(&spi->dev, "new message %p submitted for %s\n", + msg, dev_name(&spi->dev)); + + atmel_spi_lock(as); + cs_activate(as, spi); + + as->cs_active = true; + as->keep_cs = false; + + msg->status = 0; + msg->actual_length = 0; + + list_for_each_entry(xfer, &msg->transfers, transfer_list) { + ret = atmel_spi_one_transfer(master, msg, xfer); + if (ret) + goto msg_done; + } + + if (as->use_pdc) + atmel_spi_disable_pdc_transfer(as); + + list_for_each_entry(xfer, &msg->transfers, transfer_list) { + dev_dbg(&spi->dev, + " xfer %p: len %u tx %p/%pad rx %p/%pad\n", + xfer, xfer->len, + xfer->tx_buf, &xfer->tx_dma, + xfer->rx_buf, &xfer->rx_dma); + } + +msg_done: + if (!as->keep_cs) + cs_deactivate(as, msg->spi); + + atmel_spi_unlock(as); + + msg->status = as->done_status; + spi_finalize_current_message(spi->master); + + return ret; +} + +static void atmel_spi_cleanup(struct spi_device *spi) +{ + struct atmel_spi_device *asd = spi->controller_state; + unsigned gpio = (unsigned long) spi->controller_data; + + if (!asd) + return; + + spi->controller_state = NULL; + gpio_free(gpio); + kfree(asd); +} + +static inline unsigned int atmel_get_version(struct atmel_spi *as) +{ + return spi_readl(as, VERSION) & 0x00000fff; +} + +static void atmel_get_caps(struct atmel_spi *as) +{ + unsigned int version; + + version = atmel_get_version(as); + dev_info(&as->pdev->dev, "version: 0x%x\n", version); + + as->caps.is_spi2 = version > 0x121; + as->caps.has_wdrbt = version >= 0x210; + as->caps.has_dma_support = version >= 0x212; +} + +/*-------------------------------------------------------------------------*/ + +static int atmel_spi_probe(struct platform_device *pdev) +{ + struct resource *regs; + int irq; + struct clk *clk; + int ret; + struct spi_master *master; + struct atmel_spi *as; + + /* Select default pin state */ + pinctrl_pm_select_default_state(&pdev->dev); + + regs = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!regs) + return -ENXIO; + + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; + + clk = devm_clk_get(&pdev->dev, "spi_clk"); + if (IS_ERR(clk)) + return PTR_ERR(clk); + + /* setup spi core then atmel-specific driver state */ + ret = -ENOMEM; + master = spi_alloc_master(&pdev->dev, sizeof(*as)); + if (!master) + goto out_free; + + /* the spi->mode bits understood by this driver: */ + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH; + master->bits_per_word_mask = SPI_BPW_RANGE_MASK(8, 16); + master->dev.of_node = pdev->dev.of_node; + master->bus_num = pdev->id; + master->num_chipselect = master->dev.of_node ? 0 : 4; + master->setup = atmel_spi_setup; + master->transfer_one_message = atmel_spi_transfer_one_message; + master->cleanup = atmel_spi_cleanup; + master->auto_runtime_pm = true; + platform_set_drvdata(pdev, master); + + as = spi_master_get_devdata(master); + + /* + * Scratch buffer is used for throwaway rx and tx data. + * It's coherent to minimize dcache pollution. + */ + as->buffer = dma_alloc_coherent(&pdev->dev, BUFFER_SIZE, + &as->buffer_dma, GFP_KERNEL); + if (!as->buffer) + goto out_free; + + spin_lock_init(&as->lock); + + as->pdev = pdev; + as->regs = devm_ioremap_resource(&pdev->dev, regs); + if (IS_ERR(as->regs)) { + ret = PTR_ERR(as->regs); + goto out_free_buffer; + } + as->phybase = regs->start; + as->irq = irq; + as->clk = clk; + + init_completion(&as->xfer_completion); + + atmel_get_caps(as); + + as->use_dma = false; + as->use_pdc = false; + if (as->caps.has_dma_support) { + ret = atmel_spi_configure_dma(as); + if (ret == 0) + as->use_dma = true; + else if (ret == -EPROBE_DEFER) + return ret; + } else { + as->use_pdc = true; + } + + if (as->caps.has_dma_support && !as->use_dma) + dev_info(&pdev->dev, "Atmel SPI Controller using PIO only\n"); + + if (as->use_pdc) { + ret = devm_request_irq(&pdev->dev, irq, atmel_spi_pdc_interrupt, + 0, dev_name(&pdev->dev), master); + } else { + ret = devm_request_irq(&pdev->dev, irq, atmel_spi_pio_interrupt, + 0, dev_name(&pdev->dev), master); + } + if (ret) + goto out_unmap_regs; + + /* Initialize the hardware */ + ret = clk_prepare_enable(clk); + if (ret) + goto out_free_irq; + spi_writel(as, CR, SPI_BIT(SWRST)); + spi_writel(as, CR, SPI_BIT(SWRST)); /* AT91SAM9263 Rev B workaround */ + if (as->caps.has_wdrbt) { + spi_writel(as, MR, SPI_BIT(WDRBT) | SPI_BIT(MODFDIS) + | SPI_BIT(MSTR)); + } else { + spi_writel(as, MR, SPI_BIT(MSTR) | SPI_BIT(MODFDIS)); + } + + if (as->use_pdc) + spi_writel(as, PTCR, SPI_BIT(RXTDIS) | SPI_BIT(TXTDIS)); + spi_writel(as, CR, SPI_BIT(SPIEN)); + + /* go! */ + dev_info(&pdev->dev, "Atmel SPI Controller at 0x%08lx (irq %d)\n", + (unsigned long)regs->start, irq); + + pm_runtime_set_autosuspend_delay(&pdev->dev, AUTOSUSPEND_TIMEOUT); + pm_runtime_use_autosuspend(&pdev->dev); + pm_runtime_set_active(&pdev->dev); + pm_runtime_enable(&pdev->dev); + + ret = devm_spi_register_master(&pdev->dev, master); + if (ret) + goto out_free_dma; + + return 0; + +out_free_dma: + pm_runtime_disable(&pdev->dev); + pm_runtime_set_suspended(&pdev->dev); + + if (as->use_dma) + atmel_spi_release_dma(as); + + spi_writel(as, CR, SPI_BIT(SWRST)); + spi_writel(as, CR, SPI_BIT(SWRST)); /* AT91SAM9263 Rev B workaround */ + clk_disable_unprepare(clk); +out_free_irq: +out_unmap_regs: +out_free_buffer: + dma_free_coherent(&pdev->dev, BUFFER_SIZE, as->buffer, + as->buffer_dma); +out_free: + spi_master_put(master); + return ret; +} + +static int atmel_spi_remove(struct platform_device *pdev) +{ + struct spi_master *master = platform_get_drvdata(pdev); + struct atmel_spi *as = spi_master_get_devdata(master); + + pm_runtime_get_sync(&pdev->dev); + + /* reset the hardware and block queue progress */ + spin_lock_irq(&as->lock); + if (as->use_dma) { + atmel_spi_stop_dma(as); + atmel_spi_release_dma(as); + } + + spi_writel(as, CR, SPI_BIT(SWRST)); + spi_writel(as, CR, SPI_BIT(SWRST)); /* AT91SAM9263 Rev B workaround */ + spi_readl(as, SR); + spin_unlock_irq(&as->lock); + + dma_free_coherent(&pdev->dev, BUFFER_SIZE, as->buffer, + as->buffer_dma); + + clk_disable_unprepare(as->clk); + + pm_runtime_put_noidle(&pdev->dev); + pm_runtime_disable(&pdev->dev); + + return 0; +} + +#ifdef CONFIG_PM +static int atmel_spi_runtime_suspend(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct atmel_spi *as = spi_master_get_devdata(master); + + clk_disable_unprepare(as->clk); + pinctrl_pm_select_sleep_state(dev); + + return 0; +} + +static int atmel_spi_runtime_resume(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct atmel_spi *as = spi_master_get_devdata(master); + + pinctrl_pm_select_default_state(dev); + + return clk_prepare_enable(as->clk); +} + +static int atmel_spi_suspend(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + int ret; + + /* Stop the queue running */ + ret = spi_master_suspend(master); + if (ret) { + dev_warn(dev, "cannot suspend master\n"); + return ret; + } + + if (!pm_runtime_suspended(dev)) + atmel_spi_runtime_suspend(dev); + + return 0; +} + +static int atmel_spi_resume(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + int ret; + + if (!pm_runtime_suspended(dev)) { + ret = atmel_spi_runtime_resume(dev); + if (ret) + return ret; + } + + /* Start the queue running */ + ret = spi_master_resume(master); + if (ret) + dev_err(dev, "problem starting queue (%d)\n", ret); + + return ret; +} + +static const struct dev_pm_ops atmel_spi_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(atmel_spi_suspend, atmel_spi_resume) + SET_RUNTIME_PM_OPS(atmel_spi_runtime_suspend, + atmel_spi_runtime_resume, NULL) +}; +#define ATMEL_SPI_PM_OPS (&atmel_spi_pm_ops) +#else +#define ATMEL_SPI_PM_OPS NULL +#endif + +#if defined(CONFIG_OF) +static const struct of_device_id atmel_spi_dt_ids[] = { + { .compatible = "atmel,at91rm9200-spi" }, + { /* sentinel */ } +}; + +MODULE_DEVICE_TABLE(of, atmel_spi_dt_ids); +#endif + +static struct platform_driver atmel_spi_driver = { + .driver = { + .name = "atmel_spi", + .pm = ATMEL_SPI_PM_OPS, + .of_match_table = of_match_ptr(atmel_spi_dt_ids), + }, + .probe = atmel_spi_probe, + .remove = atmel_spi_remove, +}; +module_platform_driver(atmel_spi_driver); + +MODULE_DESCRIPTION("Atmel AT32/AT91 SPI Controller driver"); +MODULE_AUTHOR("Haavard Skinnemoen (Atmel)"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:atmel_spi"); diff --git a/drivers/spi/spi-au1550.c b/drivers/spi/spi-au1550.c new file mode 100644 index 000000000..f45e085c0 --- /dev/null +++ b/drivers/spi/spi-au1550.c @@ -0,0 +1,1002 @@ +/* + * au1550 psc spi controller driver + * may work also with au1200, au1210, au1250 + * will not work on au1000, au1100 and au1500 (no full spi controller there) + * + * Copyright (c) 2006 ATRON electronic GmbH + * Author: Jan Nikitenko <jan.nikitenko@gmail.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/slab.h> +#include <linux/errno.h> +#include <linux/module.h> +#include <linux/device.h> +#include <linux/platform_device.h> +#include <linux/resource.h> +#include <linux/spi/spi.h> +#include <linux/spi/spi_bitbang.h> +#include <linux/dma-mapping.h> +#include <linux/completion.h> +#include <asm/mach-au1x00/au1000.h> +#include <asm/mach-au1x00/au1xxx_psc.h> +#include <asm/mach-au1x00/au1xxx_dbdma.h> + +#include <asm/mach-au1x00/au1550_spi.h> + +static unsigned usedma = 1; +module_param(usedma, uint, 0644); + +/* +#define AU1550_SPI_DEBUG_LOOPBACK +*/ + + +#define AU1550_SPI_DBDMA_DESCRIPTORS 1 +#define AU1550_SPI_DMA_RXTMP_MINSIZE 2048U + +struct au1550_spi { + struct spi_bitbang bitbang; + + volatile psc_spi_t __iomem *regs; + int irq; + + unsigned len; + unsigned tx_count; + unsigned rx_count; + const u8 *tx; + u8 *rx; + + void (*rx_word)(struct au1550_spi *hw); + void (*tx_word)(struct au1550_spi *hw); + int (*txrx_bufs)(struct spi_device *spi, struct spi_transfer *t); + irqreturn_t (*irq_callback)(struct au1550_spi *hw); + + struct completion master_done; + + unsigned usedma; + u32 dma_tx_id; + u32 dma_rx_id; + u32 dma_tx_ch; + u32 dma_rx_ch; + + u8 *dma_rx_tmpbuf; + unsigned dma_rx_tmpbuf_size; + u32 dma_rx_tmpbuf_addr; + + struct spi_master *master; + struct device *dev; + struct au1550_spi_info *pdata; + struct resource *ioarea; +}; + + +/* we use an 8-bit memory device for dma transfers to/from spi fifo */ +static dbdev_tab_t au1550_spi_mem_dbdev = +{ + .dev_id = DBDMA_MEM_CHAN, + .dev_flags = DEV_FLAGS_ANYUSE|DEV_FLAGS_SYNC, + .dev_tsize = 0, + .dev_devwidth = 8, + .dev_physaddr = 0x00000000, + .dev_intlevel = 0, + .dev_intpolarity = 0 +}; + +static int ddma_memid; /* id to above mem dma device */ + +static void au1550_spi_bits_handlers_set(struct au1550_spi *hw, int bpw); + + +/* + * compute BRG and DIV bits to setup spi clock based on main input clock rate + * that was specified in platform data structure + * according to au1550 datasheet: + * psc_tempclk = psc_mainclk / (2 << DIV) + * spiclk = psc_tempclk / (2 * (BRG + 1)) + * BRG valid range is 4..63 + * DIV valid range is 0..3 + */ +static u32 au1550_spi_baudcfg(struct au1550_spi *hw, unsigned speed_hz) +{ + u32 mainclk_hz = hw->pdata->mainclk_hz; + u32 div, brg; + + for (div = 0; div < 4; div++) { + brg = mainclk_hz / speed_hz / (4 << div); + /* now we have BRG+1 in brg, so count with that */ + if (brg < (4 + 1)) { + brg = (4 + 1); /* speed_hz too big */ + break; /* set lowest brg (div is == 0) */ + } + if (brg <= (63 + 1)) + break; /* we have valid brg and div */ + } + if (div == 4) { + div = 3; /* speed_hz too small */ + brg = (63 + 1); /* set highest brg and div */ + } + brg--; + return PSC_SPICFG_SET_BAUD(brg) | PSC_SPICFG_SET_DIV(div); +} + +static inline void au1550_spi_mask_ack_all(struct au1550_spi *hw) +{ + hw->regs->psc_spimsk = + PSC_SPIMSK_MM | PSC_SPIMSK_RR | PSC_SPIMSK_RO + | PSC_SPIMSK_RU | PSC_SPIMSK_TR | PSC_SPIMSK_TO + | PSC_SPIMSK_TU | PSC_SPIMSK_SD | PSC_SPIMSK_MD; + wmb(); /* drain writebuffer */ + + hw->regs->psc_spievent = + PSC_SPIEVNT_MM | PSC_SPIEVNT_RR | PSC_SPIEVNT_RO + | PSC_SPIEVNT_RU | PSC_SPIEVNT_TR | PSC_SPIEVNT_TO + | PSC_SPIEVNT_TU | PSC_SPIEVNT_SD | PSC_SPIEVNT_MD; + wmb(); /* drain writebuffer */ +} + +static void au1550_spi_reset_fifos(struct au1550_spi *hw) +{ + u32 pcr; + + hw->regs->psc_spipcr = PSC_SPIPCR_RC | PSC_SPIPCR_TC; + wmb(); /* drain writebuffer */ + do { + pcr = hw->regs->psc_spipcr; + wmb(); /* drain writebuffer */ + } while (pcr != 0); +} + +/* + * dma transfers are used for the most common spi word size of 8-bits + * we cannot easily change already set up dma channels' width, so if we wanted + * dma support for more than 8-bit words (up to 24 bits), we would need to + * setup dma channels from scratch on each spi transfer, based on bits_per_word + * instead we have pre set up 8 bit dma channels supporting spi 4 to 8 bits + * transfers, and 9 to 24 bits spi transfers will be done in pio irq based mode + * callbacks to handle dma or pio are set up in au1550_spi_bits_handlers_set() + */ +static void au1550_spi_chipsel(struct spi_device *spi, int value) +{ + struct au1550_spi *hw = spi_master_get_devdata(spi->master); + unsigned cspol = spi->mode & SPI_CS_HIGH ? 1 : 0; + u32 cfg, stat; + + switch (value) { + case BITBANG_CS_INACTIVE: + if (hw->pdata->deactivate_cs) + hw->pdata->deactivate_cs(hw->pdata, spi->chip_select, + cspol); + break; + + case BITBANG_CS_ACTIVE: + au1550_spi_bits_handlers_set(hw, spi->bits_per_word); + + cfg = hw->regs->psc_spicfg; + wmb(); /* drain writebuffer */ + hw->regs->psc_spicfg = cfg & ~PSC_SPICFG_DE_ENABLE; + wmb(); /* drain writebuffer */ + + if (spi->mode & SPI_CPOL) + cfg |= PSC_SPICFG_BI; + else + cfg &= ~PSC_SPICFG_BI; + if (spi->mode & SPI_CPHA) + cfg &= ~PSC_SPICFG_CDE; + else + cfg |= PSC_SPICFG_CDE; + + if (spi->mode & SPI_LSB_FIRST) + cfg |= PSC_SPICFG_MLF; + else + cfg &= ~PSC_SPICFG_MLF; + + if (hw->usedma && spi->bits_per_word <= 8) + cfg &= ~PSC_SPICFG_DD_DISABLE; + else + cfg |= PSC_SPICFG_DD_DISABLE; + cfg = PSC_SPICFG_CLR_LEN(cfg); + cfg |= PSC_SPICFG_SET_LEN(spi->bits_per_word); + + cfg = PSC_SPICFG_CLR_BAUD(cfg); + cfg &= ~PSC_SPICFG_SET_DIV(3); + cfg |= au1550_spi_baudcfg(hw, spi->max_speed_hz); + + hw->regs->psc_spicfg = cfg | PSC_SPICFG_DE_ENABLE; + wmb(); /* drain writebuffer */ + do { + stat = hw->regs->psc_spistat; + wmb(); /* drain writebuffer */ + } while ((stat & PSC_SPISTAT_DR) == 0); + + if (hw->pdata->activate_cs) + hw->pdata->activate_cs(hw->pdata, spi->chip_select, + cspol); + break; + } +} + +static int au1550_spi_setupxfer(struct spi_device *spi, struct spi_transfer *t) +{ + struct au1550_spi *hw = spi_master_get_devdata(spi->master); + unsigned bpw, hz; + u32 cfg, stat; + + bpw = spi->bits_per_word; + hz = spi->max_speed_hz; + if (t) { + if (t->bits_per_word) + bpw = t->bits_per_word; + if (t->speed_hz) + hz = t->speed_hz; + } + + if (!hz) + return -EINVAL; + + au1550_spi_bits_handlers_set(hw, spi->bits_per_word); + + cfg = hw->regs->psc_spicfg; + wmb(); /* drain writebuffer */ + hw->regs->psc_spicfg = cfg & ~PSC_SPICFG_DE_ENABLE; + wmb(); /* drain writebuffer */ + + if (hw->usedma && bpw <= 8) + cfg &= ~PSC_SPICFG_DD_DISABLE; + else + cfg |= PSC_SPICFG_DD_DISABLE; + cfg = PSC_SPICFG_CLR_LEN(cfg); + cfg |= PSC_SPICFG_SET_LEN(bpw); + + cfg = PSC_SPICFG_CLR_BAUD(cfg); + cfg &= ~PSC_SPICFG_SET_DIV(3); + cfg |= au1550_spi_baudcfg(hw, hz); + + hw->regs->psc_spicfg = cfg; + wmb(); /* drain writebuffer */ + + if (cfg & PSC_SPICFG_DE_ENABLE) { + do { + stat = hw->regs->psc_spistat; + wmb(); /* drain writebuffer */ + } while ((stat & PSC_SPISTAT_DR) == 0); + } + + au1550_spi_reset_fifos(hw); + au1550_spi_mask_ack_all(hw); + return 0; +} + +/* + * for dma spi transfers, we have to setup rx channel, otherwise there is + * no reliable way how to recognize that spi transfer is done + * dma complete callbacks are called before real spi transfer is finished + * and if only tx dma channel is set up (and rx fifo overflow event masked) + * spi master done event irq is not generated unless rx fifo is empty (emptied) + * so we need rx tmp buffer to use for rx dma if user does not provide one + */ +static int au1550_spi_dma_rxtmp_alloc(struct au1550_spi *hw, unsigned size) +{ + hw->dma_rx_tmpbuf = kmalloc(size, GFP_KERNEL); + if (!hw->dma_rx_tmpbuf) + return -ENOMEM; + hw->dma_rx_tmpbuf_size = size; + hw->dma_rx_tmpbuf_addr = dma_map_single(hw->dev, hw->dma_rx_tmpbuf, + size, DMA_FROM_DEVICE); + if (dma_mapping_error(hw->dev, hw->dma_rx_tmpbuf_addr)) { + kfree(hw->dma_rx_tmpbuf); + hw->dma_rx_tmpbuf = 0; + hw->dma_rx_tmpbuf_size = 0; + return -EFAULT; + } + return 0; +} + +static void au1550_spi_dma_rxtmp_free(struct au1550_spi *hw) +{ + dma_unmap_single(hw->dev, hw->dma_rx_tmpbuf_addr, + hw->dma_rx_tmpbuf_size, DMA_FROM_DEVICE); + kfree(hw->dma_rx_tmpbuf); + hw->dma_rx_tmpbuf = 0; + hw->dma_rx_tmpbuf_size = 0; +} + +static int au1550_spi_dma_txrxb(struct spi_device *spi, struct spi_transfer *t) +{ + struct au1550_spi *hw = spi_master_get_devdata(spi->master); + dma_addr_t dma_tx_addr; + dma_addr_t dma_rx_addr; + u32 res; + + hw->len = t->len; + hw->tx_count = 0; + hw->rx_count = 0; + + hw->tx = t->tx_buf; + hw->rx = t->rx_buf; + dma_tx_addr = t->tx_dma; + dma_rx_addr = t->rx_dma; + + /* + * check if buffers are already dma mapped, map them otherwise: + * - first map the TX buffer, so cache data gets written to memory + * - then map the RX buffer, so that cache entries (with + * soon-to-be-stale data) get removed + * use rx buffer in place of tx if tx buffer was not provided + * use temp rx buffer (preallocated or realloc to fit) for rx dma + */ + if (t->tx_buf) { + if (t->tx_dma == 0) { /* if DMA_ADDR_INVALID, map it */ + dma_tx_addr = dma_map_single(hw->dev, + (void *)t->tx_buf, + t->len, DMA_TO_DEVICE); + if (dma_mapping_error(hw->dev, dma_tx_addr)) + dev_err(hw->dev, "tx dma map error\n"); + } + } + + if (t->rx_buf) { + if (t->rx_dma == 0) { /* if DMA_ADDR_INVALID, map it */ + dma_rx_addr = dma_map_single(hw->dev, + (void *)t->rx_buf, + t->len, DMA_FROM_DEVICE); + if (dma_mapping_error(hw->dev, dma_rx_addr)) + dev_err(hw->dev, "rx dma map error\n"); + } + } else { + if (t->len > hw->dma_rx_tmpbuf_size) { + int ret; + + au1550_spi_dma_rxtmp_free(hw); + ret = au1550_spi_dma_rxtmp_alloc(hw, max(t->len, + AU1550_SPI_DMA_RXTMP_MINSIZE)); + if (ret < 0) + return ret; + } + hw->rx = hw->dma_rx_tmpbuf; + dma_rx_addr = hw->dma_rx_tmpbuf_addr; + dma_sync_single_for_device(hw->dev, dma_rx_addr, + t->len, DMA_FROM_DEVICE); + } + + if (!t->tx_buf) { + dma_sync_single_for_device(hw->dev, dma_rx_addr, + t->len, DMA_BIDIRECTIONAL); + hw->tx = hw->rx; + } + + /* put buffers on the ring */ + res = au1xxx_dbdma_put_dest(hw->dma_rx_ch, virt_to_phys(hw->rx), + t->len, DDMA_FLAGS_IE); + if (!res) + dev_err(hw->dev, "rx dma put dest error\n"); + + res = au1xxx_dbdma_put_source(hw->dma_tx_ch, virt_to_phys(hw->tx), + t->len, DDMA_FLAGS_IE); + if (!res) + dev_err(hw->dev, "tx dma put source error\n"); + + au1xxx_dbdma_start(hw->dma_rx_ch); + au1xxx_dbdma_start(hw->dma_tx_ch); + + /* by default enable nearly all events interrupt */ + hw->regs->psc_spimsk = PSC_SPIMSK_SD; + wmb(); /* drain writebuffer */ + + /* start the transfer */ + hw->regs->psc_spipcr = PSC_SPIPCR_MS; + wmb(); /* drain writebuffer */ + + wait_for_completion(&hw->master_done); + + au1xxx_dbdma_stop(hw->dma_tx_ch); + au1xxx_dbdma_stop(hw->dma_rx_ch); + + if (!t->rx_buf) { + /* using the temporal preallocated and premapped buffer */ + dma_sync_single_for_cpu(hw->dev, dma_rx_addr, t->len, + DMA_FROM_DEVICE); + } + /* unmap buffers if mapped above */ + if (t->rx_buf && t->rx_dma == 0 ) + dma_unmap_single(hw->dev, dma_rx_addr, t->len, + DMA_FROM_DEVICE); + if (t->tx_buf && t->tx_dma == 0 ) + dma_unmap_single(hw->dev, dma_tx_addr, t->len, + DMA_TO_DEVICE); + + return hw->rx_count < hw->tx_count ? hw->rx_count : hw->tx_count; +} + +static irqreturn_t au1550_spi_dma_irq_callback(struct au1550_spi *hw) +{ + u32 stat, evnt; + + stat = hw->regs->psc_spistat; + evnt = hw->regs->psc_spievent; + wmb(); /* drain writebuffer */ + if ((stat & PSC_SPISTAT_DI) == 0) { + dev_err(hw->dev, "Unexpected IRQ!\n"); + return IRQ_NONE; + } + + if ((evnt & (PSC_SPIEVNT_MM | PSC_SPIEVNT_RO + | PSC_SPIEVNT_RU | PSC_SPIEVNT_TO + | PSC_SPIEVNT_TU | PSC_SPIEVNT_SD)) + != 0) { + /* + * due to an spi error we consider transfer as done, + * so mask all events until before next transfer start + * and stop the possibly running dma immediately + */ + au1550_spi_mask_ack_all(hw); + au1xxx_dbdma_stop(hw->dma_rx_ch); + au1xxx_dbdma_stop(hw->dma_tx_ch); + + /* get number of transferred bytes */ + hw->rx_count = hw->len - au1xxx_get_dma_residue(hw->dma_rx_ch); + hw->tx_count = hw->len - au1xxx_get_dma_residue(hw->dma_tx_ch); + + au1xxx_dbdma_reset(hw->dma_rx_ch); + au1xxx_dbdma_reset(hw->dma_tx_ch); + au1550_spi_reset_fifos(hw); + + if (evnt == PSC_SPIEVNT_RO) + dev_err(hw->dev, + "dma transfer: receive FIFO overflow!\n"); + else + dev_err(hw->dev, + "dma transfer: unexpected SPI error " + "(event=0x%x stat=0x%x)!\n", evnt, stat); + + complete(&hw->master_done); + return IRQ_HANDLED; + } + + if ((evnt & PSC_SPIEVNT_MD) != 0) { + /* transfer completed successfully */ + au1550_spi_mask_ack_all(hw); + hw->rx_count = hw->len; + hw->tx_count = hw->len; + complete(&hw->master_done); + } + return IRQ_HANDLED; +} + + +/* routines to handle different word sizes in pio mode */ +#define AU1550_SPI_RX_WORD(size, mask) \ +static void au1550_spi_rx_word_##size(struct au1550_spi *hw) \ +{ \ + u32 fifoword = hw->regs->psc_spitxrx & (u32)(mask); \ + wmb(); /* drain writebuffer */ \ + if (hw->rx) { \ + *(u##size *)hw->rx = (u##size)fifoword; \ + hw->rx += (size) / 8; \ + } \ + hw->rx_count += (size) / 8; \ +} + +#define AU1550_SPI_TX_WORD(size, mask) \ +static void au1550_spi_tx_word_##size(struct au1550_spi *hw) \ +{ \ + u32 fifoword = 0; \ + if (hw->tx) { \ + fifoword = *(u##size *)hw->tx & (u32)(mask); \ + hw->tx += (size) / 8; \ + } \ + hw->tx_count += (size) / 8; \ + if (hw->tx_count >= hw->len) \ + fifoword |= PSC_SPITXRX_LC; \ + hw->regs->psc_spitxrx = fifoword; \ + wmb(); /* drain writebuffer */ \ +} + +AU1550_SPI_RX_WORD(8,0xff) +AU1550_SPI_RX_WORD(16,0xffff) +AU1550_SPI_RX_WORD(32,0xffffff) +AU1550_SPI_TX_WORD(8,0xff) +AU1550_SPI_TX_WORD(16,0xffff) +AU1550_SPI_TX_WORD(32,0xffffff) + +static int au1550_spi_pio_txrxb(struct spi_device *spi, struct spi_transfer *t) +{ + u32 stat, mask; + struct au1550_spi *hw = spi_master_get_devdata(spi->master); + + hw->tx = t->tx_buf; + hw->rx = t->rx_buf; + hw->len = t->len; + hw->tx_count = 0; + hw->rx_count = 0; + + /* by default enable nearly all events after filling tx fifo */ + mask = PSC_SPIMSK_SD; + + /* fill the transmit FIFO */ + while (hw->tx_count < hw->len) { + + hw->tx_word(hw); + + if (hw->tx_count >= hw->len) { + /* mask tx fifo request interrupt as we are done */ + mask |= PSC_SPIMSK_TR; + } + + stat = hw->regs->psc_spistat; + wmb(); /* drain writebuffer */ + if (stat & PSC_SPISTAT_TF) + break; + } + + /* enable event interrupts */ + hw->regs->psc_spimsk = mask; + wmb(); /* drain writebuffer */ + + /* start the transfer */ + hw->regs->psc_spipcr = PSC_SPIPCR_MS; + wmb(); /* drain writebuffer */ + + wait_for_completion(&hw->master_done); + + return hw->rx_count < hw->tx_count ? hw->rx_count : hw->tx_count; +} + +static irqreturn_t au1550_spi_pio_irq_callback(struct au1550_spi *hw) +{ + int busy; + u32 stat, evnt; + + stat = hw->regs->psc_spistat; + evnt = hw->regs->psc_spievent; + wmb(); /* drain writebuffer */ + if ((stat & PSC_SPISTAT_DI) == 0) { + dev_err(hw->dev, "Unexpected IRQ!\n"); + return IRQ_NONE; + } + + if ((evnt & (PSC_SPIEVNT_MM | PSC_SPIEVNT_RO + | PSC_SPIEVNT_RU | PSC_SPIEVNT_TO + | PSC_SPIEVNT_SD)) + != 0) { + /* + * due to an error we consider transfer as done, + * so mask all events until before next transfer start + */ + au1550_spi_mask_ack_all(hw); + au1550_spi_reset_fifos(hw); + dev_err(hw->dev, + "pio transfer: unexpected SPI error " + "(event=0x%x stat=0x%x)!\n", evnt, stat); + complete(&hw->master_done); + return IRQ_HANDLED; + } + + /* + * while there is something to read from rx fifo + * or there is a space to write to tx fifo: + */ + do { + busy = 0; + stat = hw->regs->psc_spistat; + wmb(); /* drain writebuffer */ + + /* + * Take care to not let the Rx FIFO overflow. + * + * We only write a byte if we have read one at least. Initially, + * the write fifo is full, so we should read from the read fifo + * first. + * In case we miss a word from the read fifo, we should get a + * RO event and should back out. + */ + if (!(stat & PSC_SPISTAT_RE) && hw->rx_count < hw->len) { + hw->rx_word(hw); + busy = 1; + + if (!(stat & PSC_SPISTAT_TF) && hw->tx_count < hw->len) + hw->tx_word(hw); + } + } while (busy); + + hw->regs->psc_spievent = PSC_SPIEVNT_RR | PSC_SPIEVNT_TR; + wmb(); /* drain writebuffer */ + + /* + * Restart the SPI transmission in case of a transmit underflow. + * This seems to work despite the notes in the Au1550 data book + * of Figure 8-4 with flowchart for SPI master operation: + * + * """Note 1: An XFR Error Interrupt occurs, unless masked, + * for any of the following events: Tx FIFO Underflow, + * Rx FIFO Overflow, or Multiple-master Error + * Note 2: In case of a Tx Underflow Error, all zeroes are + * transmitted.""" + * + * By simply restarting the spi transfer on Tx Underflow Error, + * we assume that spi transfer was paused instead of zeroes + * transmittion mentioned in the Note 2 of Au1550 data book. + */ + if (evnt & PSC_SPIEVNT_TU) { + hw->regs->psc_spievent = PSC_SPIEVNT_TU | PSC_SPIEVNT_MD; + wmb(); /* drain writebuffer */ + hw->regs->psc_spipcr = PSC_SPIPCR_MS; + wmb(); /* drain writebuffer */ + } + + if (hw->rx_count >= hw->len) { + /* transfer completed successfully */ + au1550_spi_mask_ack_all(hw); + complete(&hw->master_done); + } + return IRQ_HANDLED; +} + +static int au1550_spi_txrx_bufs(struct spi_device *spi, struct spi_transfer *t) +{ + struct au1550_spi *hw = spi_master_get_devdata(spi->master); + return hw->txrx_bufs(spi, t); +} + +static irqreturn_t au1550_spi_irq(int irq, void *dev) +{ + struct au1550_spi *hw = dev; + return hw->irq_callback(hw); +} + +static void au1550_spi_bits_handlers_set(struct au1550_spi *hw, int bpw) +{ + if (bpw <= 8) { + if (hw->usedma) { + hw->txrx_bufs = &au1550_spi_dma_txrxb; + hw->irq_callback = &au1550_spi_dma_irq_callback; + } else { + hw->rx_word = &au1550_spi_rx_word_8; + hw->tx_word = &au1550_spi_tx_word_8; + hw->txrx_bufs = &au1550_spi_pio_txrxb; + hw->irq_callback = &au1550_spi_pio_irq_callback; + } + } else if (bpw <= 16) { + hw->rx_word = &au1550_spi_rx_word_16; + hw->tx_word = &au1550_spi_tx_word_16; + hw->txrx_bufs = &au1550_spi_pio_txrxb; + hw->irq_callback = &au1550_spi_pio_irq_callback; + } else { + hw->rx_word = &au1550_spi_rx_word_32; + hw->tx_word = &au1550_spi_tx_word_32; + hw->txrx_bufs = &au1550_spi_pio_txrxb; + hw->irq_callback = &au1550_spi_pio_irq_callback; + } +} + +static void au1550_spi_setup_psc_as_spi(struct au1550_spi *hw) +{ + u32 stat, cfg; + + /* set up the PSC for SPI mode */ + hw->regs->psc_ctrl = PSC_CTRL_DISABLE; + wmb(); /* drain writebuffer */ + hw->regs->psc_sel = PSC_SEL_PS_SPIMODE; + wmb(); /* drain writebuffer */ + + hw->regs->psc_spicfg = 0; + wmb(); /* drain writebuffer */ + + hw->regs->psc_ctrl = PSC_CTRL_ENABLE; + wmb(); /* drain writebuffer */ + + do { + stat = hw->regs->psc_spistat; + wmb(); /* drain writebuffer */ + } while ((stat & PSC_SPISTAT_SR) == 0); + + + cfg = hw->usedma ? 0 : PSC_SPICFG_DD_DISABLE; + cfg |= PSC_SPICFG_SET_LEN(8); + cfg |= PSC_SPICFG_RT_FIFO8 | PSC_SPICFG_TT_FIFO8; + /* use minimal allowed brg and div values as initial setting: */ + cfg |= PSC_SPICFG_SET_BAUD(4) | PSC_SPICFG_SET_DIV(0); + +#ifdef AU1550_SPI_DEBUG_LOOPBACK + cfg |= PSC_SPICFG_LB; +#endif + + hw->regs->psc_spicfg = cfg; + wmb(); /* drain writebuffer */ + + au1550_spi_mask_ack_all(hw); + + hw->regs->psc_spicfg |= PSC_SPICFG_DE_ENABLE; + wmb(); /* drain writebuffer */ + + do { + stat = hw->regs->psc_spistat; + wmb(); /* drain writebuffer */ + } while ((stat & PSC_SPISTAT_DR) == 0); + + au1550_spi_reset_fifos(hw); +} + + +static int au1550_spi_probe(struct platform_device *pdev) +{ + struct au1550_spi *hw; + struct spi_master *master; + struct resource *r; + int err = 0; + + master = spi_alloc_master(&pdev->dev, sizeof(struct au1550_spi)); + if (master == NULL) { + dev_err(&pdev->dev, "No memory for spi_master\n"); + err = -ENOMEM; + goto err_nomem; + } + + /* the spi->mode bits understood by this driver: */ + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LSB_FIRST; + master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 24); + + hw = spi_master_get_devdata(master); + + hw->master = master; + hw->pdata = dev_get_platdata(&pdev->dev); + hw->dev = &pdev->dev; + + if (hw->pdata == NULL) { + dev_err(&pdev->dev, "No platform data supplied\n"); + err = -ENOENT; + goto err_no_pdata; + } + + r = platform_get_resource(pdev, IORESOURCE_IRQ, 0); + if (!r) { + dev_err(&pdev->dev, "no IRQ\n"); + err = -ENODEV; + goto err_no_iores; + } + hw->irq = r->start; + + hw->usedma = 0; + r = platform_get_resource(pdev, IORESOURCE_DMA, 0); + if (r) { + hw->dma_tx_id = r->start; + r = platform_get_resource(pdev, IORESOURCE_DMA, 1); + if (r) { + hw->dma_rx_id = r->start; + if (usedma && ddma_memid) { + if (pdev->dev.dma_mask == NULL) + dev_warn(&pdev->dev, "no dma mask\n"); + else + hw->usedma = 1; + } + } + } + + r = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!r) { + dev_err(&pdev->dev, "no mmio resource\n"); + err = -ENODEV; + goto err_no_iores; + } + + hw->ioarea = request_mem_region(r->start, sizeof(psc_spi_t), + pdev->name); + if (!hw->ioarea) { + dev_err(&pdev->dev, "Cannot reserve iomem region\n"); + err = -ENXIO; + goto err_no_iores; + } + + hw->regs = (psc_spi_t __iomem *)ioremap(r->start, sizeof(psc_spi_t)); + if (!hw->regs) { + dev_err(&pdev->dev, "cannot ioremap\n"); + err = -ENXIO; + goto err_ioremap; + } + + platform_set_drvdata(pdev, hw); + + init_completion(&hw->master_done); + + hw->bitbang.master = hw->master; + hw->bitbang.setup_transfer = au1550_spi_setupxfer; + hw->bitbang.chipselect = au1550_spi_chipsel; + hw->bitbang.txrx_bufs = au1550_spi_txrx_bufs; + + if (hw->usedma) { + hw->dma_tx_ch = au1xxx_dbdma_chan_alloc(ddma_memid, + hw->dma_tx_id, NULL, (void *)hw); + if (hw->dma_tx_ch == 0) { + dev_err(&pdev->dev, + "Cannot allocate tx dma channel\n"); + err = -ENXIO; + goto err_no_txdma; + } + au1xxx_dbdma_set_devwidth(hw->dma_tx_ch, 8); + if (au1xxx_dbdma_ring_alloc(hw->dma_tx_ch, + AU1550_SPI_DBDMA_DESCRIPTORS) == 0) { + dev_err(&pdev->dev, + "Cannot allocate tx dma descriptors\n"); + err = -ENXIO; + goto err_no_txdma_descr; + } + + + hw->dma_rx_ch = au1xxx_dbdma_chan_alloc(hw->dma_rx_id, + ddma_memid, NULL, (void *)hw); + if (hw->dma_rx_ch == 0) { + dev_err(&pdev->dev, + "Cannot allocate rx dma channel\n"); + err = -ENXIO; + goto err_no_rxdma; + } + au1xxx_dbdma_set_devwidth(hw->dma_rx_ch, 8); + if (au1xxx_dbdma_ring_alloc(hw->dma_rx_ch, + AU1550_SPI_DBDMA_DESCRIPTORS) == 0) { + dev_err(&pdev->dev, + "Cannot allocate rx dma descriptors\n"); + err = -ENXIO; + goto err_no_rxdma_descr; + } + + err = au1550_spi_dma_rxtmp_alloc(hw, + AU1550_SPI_DMA_RXTMP_MINSIZE); + if (err < 0) { + dev_err(&pdev->dev, + "Cannot allocate initial rx dma tmp buffer\n"); + goto err_dma_rxtmp_alloc; + } + } + + au1550_spi_bits_handlers_set(hw, 8); + + err = request_irq(hw->irq, au1550_spi_irq, 0, pdev->name, hw); + if (err) { + dev_err(&pdev->dev, "Cannot claim IRQ\n"); + goto err_no_irq; + } + + master->bus_num = pdev->id; + master->num_chipselect = hw->pdata->num_chipselect; + + /* + * precompute valid range for spi freq - from au1550 datasheet: + * psc_tempclk = psc_mainclk / (2 << DIV) + * spiclk = psc_tempclk / (2 * (BRG + 1)) + * BRG valid range is 4..63 + * DIV valid range is 0..3 + * round the min and max frequencies to values that would still + * produce valid brg and div + */ + { + int min_div = (2 << 0) * (2 * (4 + 1)); + int max_div = (2 << 3) * (2 * (63 + 1)); + master->max_speed_hz = hw->pdata->mainclk_hz / min_div; + master->min_speed_hz = + hw->pdata->mainclk_hz / (max_div + 1) + 1; + } + + au1550_spi_setup_psc_as_spi(hw); + + err = spi_bitbang_start(&hw->bitbang); + if (err) { + dev_err(&pdev->dev, "Failed to register SPI master\n"); + goto err_register; + } + + dev_info(&pdev->dev, + "spi master registered: bus_num=%d num_chipselect=%d\n", + master->bus_num, master->num_chipselect); + + return 0; + +err_register: + free_irq(hw->irq, hw); + +err_no_irq: + au1550_spi_dma_rxtmp_free(hw); + +err_dma_rxtmp_alloc: +err_no_rxdma_descr: + if (hw->usedma) + au1xxx_dbdma_chan_free(hw->dma_rx_ch); + +err_no_rxdma: +err_no_txdma_descr: + if (hw->usedma) + au1xxx_dbdma_chan_free(hw->dma_tx_ch); + +err_no_txdma: + iounmap((void __iomem *)hw->regs); + +err_ioremap: + release_mem_region(r->start, sizeof(psc_spi_t)); + +err_no_iores: +err_no_pdata: + spi_master_put(hw->master); + +err_nomem: + return err; +} + +static int au1550_spi_remove(struct platform_device *pdev) +{ + struct au1550_spi *hw = platform_get_drvdata(pdev); + + dev_info(&pdev->dev, "spi master remove: bus_num=%d\n", + hw->master->bus_num); + + spi_bitbang_stop(&hw->bitbang); + free_irq(hw->irq, hw); + iounmap((void __iomem *)hw->regs); + release_mem_region(hw->ioarea->start, sizeof(psc_spi_t)); + + if (hw->usedma) { + au1550_spi_dma_rxtmp_free(hw); + au1xxx_dbdma_chan_free(hw->dma_rx_ch); + au1xxx_dbdma_chan_free(hw->dma_tx_ch); + } + + spi_master_put(hw->master); + return 0; +} + +/* work with hotplug and coldplug */ +MODULE_ALIAS("platform:au1550-spi"); + +static struct platform_driver au1550_spi_drv = { + .probe = au1550_spi_probe, + .remove = au1550_spi_remove, + .driver = { + .name = "au1550-spi", + }, +}; + +static int __init au1550_spi_init(void) +{ + /* + * create memory device with 8 bits dev_devwidth + * needed for proper byte ordering to spi fifo + */ + switch (alchemy_get_cputype()) { + case ALCHEMY_CPU_AU1550: + case ALCHEMY_CPU_AU1200: + case ALCHEMY_CPU_AU1300: + break; + default: + return -ENODEV; + } + + if (usedma) { + ddma_memid = au1xxx_ddma_add_device(&au1550_spi_mem_dbdev); + if (!ddma_memid) + printk(KERN_ERR "au1550-spi: cannot add memory" + "dbdma device\n"); + } + return platform_driver_register(&au1550_spi_drv); +} +module_init(au1550_spi_init); + +static void __exit au1550_spi_exit(void) +{ + if (usedma && ddma_memid) + au1xxx_ddma_del_device(ddma_memid); + platform_driver_unregister(&au1550_spi_drv); +} +module_exit(au1550_spi_exit); + +MODULE_DESCRIPTION("Au1550 PSC SPI Driver"); +MODULE_AUTHOR("Jan Nikitenko <jan.nikitenko@gmail.com>"); +MODULE_LICENSE("GPL"); diff --git a/drivers/spi/spi-bcm2835.c b/drivers/spi/spi-bcm2835.c new file mode 100644 index 000000000..37875cf94 --- /dev/null +++ b/drivers/spi/spi-bcm2835.c @@ -0,0 +1,517 @@ +/* + * Driver for Broadcom BCM2835 SPI Controllers + * + * Copyright (C) 2012 Chris Boot + * Copyright (C) 2013 Stephen Warren + * Copyright (C) 2015 Martin Sperl + * + * This driver is inspired by: + * spi-ath79.c, Copyright (C) 2009-2011 Gabor Juhos <juhosg@openwrt.org> + * spi-atmel.c, Copyright (C) 2006 Atmel Corporation + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/clk.h> +#include <linux/completion.h> +#include <linux/delay.h> +#include <linux/err.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_irq.h> +#include <linux/of_gpio.h> +#include <linux/of_device.h> +#include <linux/spi/spi.h> + +/* SPI register offsets */ +#define BCM2835_SPI_CS 0x00 +#define BCM2835_SPI_FIFO 0x04 +#define BCM2835_SPI_CLK 0x08 +#define BCM2835_SPI_DLEN 0x0c +#define BCM2835_SPI_LTOH 0x10 +#define BCM2835_SPI_DC 0x14 + +/* Bitfields in CS */ +#define BCM2835_SPI_CS_LEN_LONG 0x02000000 +#define BCM2835_SPI_CS_DMA_LEN 0x01000000 +#define BCM2835_SPI_CS_CSPOL2 0x00800000 +#define BCM2835_SPI_CS_CSPOL1 0x00400000 +#define BCM2835_SPI_CS_CSPOL0 0x00200000 +#define BCM2835_SPI_CS_RXF 0x00100000 +#define BCM2835_SPI_CS_RXR 0x00080000 +#define BCM2835_SPI_CS_TXD 0x00040000 +#define BCM2835_SPI_CS_RXD 0x00020000 +#define BCM2835_SPI_CS_DONE 0x00010000 +#define BCM2835_SPI_CS_LEN 0x00002000 +#define BCM2835_SPI_CS_REN 0x00001000 +#define BCM2835_SPI_CS_ADCS 0x00000800 +#define BCM2835_SPI_CS_INTR 0x00000400 +#define BCM2835_SPI_CS_INTD 0x00000200 +#define BCM2835_SPI_CS_DMAEN 0x00000100 +#define BCM2835_SPI_CS_TA 0x00000080 +#define BCM2835_SPI_CS_CSPOL 0x00000040 +#define BCM2835_SPI_CS_CLEAR_RX 0x00000020 +#define BCM2835_SPI_CS_CLEAR_TX 0x00000010 +#define BCM2835_SPI_CS_CPOL 0x00000008 +#define BCM2835_SPI_CS_CPHA 0x00000004 +#define BCM2835_SPI_CS_CS_10 0x00000002 +#define BCM2835_SPI_CS_CS_01 0x00000001 + +#define BCM2835_SPI_POLLING_LIMIT_US 30 +#define BCM2835_SPI_TIMEOUT_MS 30000 +#define BCM2835_SPI_MODE_BITS (SPI_CPOL | SPI_CPHA | SPI_CS_HIGH \ + | SPI_NO_CS | SPI_3WIRE) + +#define DRV_NAME "spi-bcm2835" + +struct bcm2835_spi { + void __iomem *regs; + struct clk *clk; + int irq; + const u8 *tx_buf; + u8 *rx_buf; + int tx_len; + int rx_len; +}; + +static inline u32 bcm2835_rd(struct bcm2835_spi *bs, unsigned reg) +{ + return readl(bs->regs + reg); +} + +static inline void bcm2835_wr(struct bcm2835_spi *bs, unsigned reg, u32 val) +{ + writel(val, bs->regs + reg); +} + +static inline void bcm2835_rd_fifo(struct bcm2835_spi *bs) +{ + u8 byte; + + while ((bs->rx_len) && + (bcm2835_rd(bs, BCM2835_SPI_CS) & BCM2835_SPI_CS_RXD)) { + byte = bcm2835_rd(bs, BCM2835_SPI_FIFO); + if (bs->rx_buf) + *bs->rx_buf++ = byte; + bs->rx_len--; + } +} + +static inline void bcm2835_wr_fifo(struct bcm2835_spi *bs) +{ + u8 byte; + + while ((bs->tx_len) && + (bcm2835_rd(bs, BCM2835_SPI_CS) & BCM2835_SPI_CS_TXD)) { + byte = bs->tx_buf ? *bs->tx_buf++ : 0; + bcm2835_wr(bs, BCM2835_SPI_FIFO, byte); + bs->tx_len--; + } +} + +static void bcm2835_spi_reset_hw(struct spi_master *master) +{ + struct bcm2835_spi *bs = spi_master_get_devdata(master); + u32 cs = bcm2835_rd(bs, BCM2835_SPI_CS); + + /* Disable SPI interrupts and transfer */ + cs &= ~(BCM2835_SPI_CS_INTR | + BCM2835_SPI_CS_INTD | + BCM2835_SPI_CS_TA); + /* and reset RX/TX FIFOS */ + cs |= BCM2835_SPI_CS_CLEAR_RX | BCM2835_SPI_CS_CLEAR_TX; + + /* and reset the SPI_HW */ + bcm2835_wr(bs, BCM2835_SPI_CS, cs); +} + +static irqreturn_t bcm2835_spi_interrupt(int irq, void *dev_id) +{ + struct spi_master *master = dev_id; + struct bcm2835_spi *bs = spi_master_get_devdata(master); + + /* Read as many bytes as possible from FIFO */ + bcm2835_rd_fifo(bs); + /* Write as many bytes as possible to FIFO */ + bcm2835_wr_fifo(bs); + + /* based on flags decide if we can finish the transfer */ + if (bcm2835_rd(bs, BCM2835_SPI_CS) & BCM2835_SPI_CS_DONE) { + /* Transfer complete - reset SPI HW */ + bcm2835_spi_reset_hw(master); + /* wake up the framework */ + complete(&master->xfer_completion); + } + + return IRQ_HANDLED; +} + +static int bcm2835_spi_transfer_one_poll(struct spi_master *master, + struct spi_device *spi, + struct spi_transfer *tfr, + u32 cs, + unsigned long xfer_time_us) +{ + struct bcm2835_spi *bs = spi_master_get_devdata(master); + /* set timeout to 1 second of maximum polling */ + unsigned long timeout = jiffies + HZ; + + /* enable HW block without interrupts */ + bcm2835_wr(bs, BCM2835_SPI_CS, cs | BCM2835_SPI_CS_TA); + + /* loop until finished the transfer */ + while (bs->rx_len) { + /* read from fifo as much as possible */ + bcm2835_rd_fifo(bs); + /* fill in tx fifo as much as possible */ + bcm2835_wr_fifo(bs); + /* if we still expect some data after the read, + * check for a possible timeout + */ + if (bs->rx_len && time_after(jiffies, timeout)) { + /* Transfer complete - reset SPI HW */ + bcm2835_spi_reset_hw(master); + /* and return timeout */ + return -ETIMEDOUT; + } + } + + /* Transfer complete - reset SPI HW */ + bcm2835_spi_reset_hw(master); + /* and return without waiting for completion */ + return 0; +} + +static int bcm2835_spi_transfer_one_irq(struct spi_master *master, + struct spi_device *spi, + struct spi_transfer *tfr, + u32 cs) +{ + struct bcm2835_spi *bs = spi_master_get_devdata(master); + + /* fill in fifo if we have gpio-cs + * note that there have been rare events where the native-CS + * flapped for <1us which may change the behaviour + * with gpio-cs this does not happen, so it is implemented + * only for this case + */ + if (gpio_is_valid(spi->cs_gpio)) { + /* enable HW block, but without interrupts enabled + * this would triggern an immediate interrupt + */ + bcm2835_wr(bs, BCM2835_SPI_CS, + cs | BCM2835_SPI_CS_TA); + /* fill in tx fifo as much as possible */ + bcm2835_wr_fifo(bs); + } + + /* + * Enable the HW block. This will immediately trigger a DONE (TX + * empty) interrupt, upon which we will fill the TX FIFO with the + * first TX bytes. Pre-filling the TX FIFO here to avoid the + * interrupt doesn't work:-( + */ + cs |= BCM2835_SPI_CS_INTR | BCM2835_SPI_CS_INTD | BCM2835_SPI_CS_TA; + bcm2835_wr(bs, BCM2835_SPI_CS, cs); + + /* signal that we need to wait for completion */ + return 1; +} + +static int bcm2835_spi_transfer_one(struct spi_master *master, + struct spi_device *spi, + struct spi_transfer *tfr) +{ + struct bcm2835_spi *bs = spi_master_get_devdata(master); + unsigned long spi_hz, clk_hz, cdiv; + unsigned long spi_used_hz, xfer_time_us; + u32 cs = bcm2835_rd(bs, BCM2835_SPI_CS); + + /* set clock */ + spi_hz = tfr->speed_hz; + clk_hz = clk_get_rate(bs->clk); + + if (spi_hz >= clk_hz / 2) { + cdiv = 2; /* clk_hz/2 is the fastest we can go */ + } else if (spi_hz) { + /* CDIV must be a multiple of two */ + cdiv = DIV_ROUND_UP(clk_hz, spi_hz); + cdiv += (cdiv % 2); + + if (cdiv >= 65536) + cdiv = 0; /* 0 is the slowest we can go */ + } else { + cdiv = 0; /* 0 is the slowest we can go */ + } + spi_used_hz = cdiv ? (clk_hz / cdiv) : (clk_hz / 65536); + bcm2835_wr(bs, BCM2835_SPI_CLK, cdiv); + + /* handle all the modes */ + if ((spi->mode & SPI_3WIRE) && (tfr->rx_buf)) + cs |= BCM2835_SPI_CS_REN; + if (spi->mode & SPI_CPOL) + cs |= BCM2835_SPI_CS_CPOL; + if (spi->mode & SPI_CPHA) + cs |= BCM2835_SPI_CS_CPHA; + + /* for gpio_cs set dummy CS so that no HW-CS get changed + * we can not run this in bcm2835_spi_set_cs, as it does + * not get called for cs_gpio cases, so we need to do it here + */ + if (gpio_is_valid(spi->cs_gpio) || (spi->mode & SPI_NO_CS)) + cs |= BCM2835_SPI_CS_CS_10 | BCM2835_SPI_CS_CS_01; + + /* set transmit buffers and length */ + bs->tx_buf = tfr->tx_buf; + bs->rx_buf = tfr->rx_buf; + bs->tx_len = tfr->len; + bs->rx_len = tfr->len; + + /* calculate the estimated time in us the transfer runs */ + xfer_time_us = tfr->len + * 9 /* clocks/byte - SPI-HW waits 1 clock after each byte */ + * 1000000 / spi_used_hz; + + /* for short requests run polling*/ + if (xfer_time_us <= BCM2835_SPI_POLLING_LIMIT_US) + return bcm2835_spi_transfer_one_poll(master, spi, tfr, + cs, xfer_time_us); + + return bcm2835_spi_transfer_one_irq(master, spi, tfr, cs); +} + +static void bcm2835_spi_handle_err(struct spi_master *master, + struct spi_message *msg) +{ + bcm2835_spi_reset_hw(master); +} + +static void bcm2835_spi_set_cs(struct spi_device *spi, bool gpio_level) +{ + /* + * we can assume that we are "native" as per spi_set_cs + * calling us ONLY when cs_gpio is not set + * we can also assume that we are CS < 3 as per bcm2835_spi_setup + * we would not get called because of error handling there. + * the level passed is the electrical level not enabled/disabled + * so it has to get translated back to enable/disable + * see spi_set_cs in spi.c for the implementation + */ + + struct spi_master *master = spi->master; + struct bcm2835_spi *bs = spi_master_get_devdata(master); + u32 cs = bcm2835_rd(bs, BCM2835_SPI_CS); + bool enable; + + /* calculate the enable flag from the passed gpio_level */ + enable = (spi->mode & SPI_CS_HIGH) ? gpio_level : !gpio_level; + + /* set flags for "reverse" polarity in the registers */ + if (spi->mode & SPI_CS_HIGH) { + /* set the correct CS-bits */ + cs |= BCM2835_SPI_CS_CSPOL; + cs |= BCM2835_SPI_CS_CSPOL0 << spi->chip_select; + } else { + /* clean the CS-bits */ + cs &= ~BCM2835_SPI_CS_CSPOL; + cs &= ~(BCM2835_SPI_CS_CSPOL0 << spi->chip_select); + } + + /* select the correct chip_select depending on disabled/enabled */ + if (enable) { + /* set cs correctly */ + if (spi->mode & SPI_NO_CS) { + /* use the "undefined" chip-select */ + cs |= BCM2835_SPI_CS_CS_10 | BCM2835_SPI_CS_CS_01; + } else { + /* set the chip select */ + cs &= ~(BCM2835_SPI_CS_CS_10 | BCM2835_SPI_CS_CS_01); + cs |= spi->chip_select; + } + } else { + /* disable CSPOL which puts HW-CS into deselected state */ + cs &= ~BCM2835_SPI_CS_CSPOL; + /* use the "undefined" chip-select as precaution */ + cs |= BCM2835_SPI_CS_CS_10 | BCM2835_SPI_CS_CS_01; + } + + /* finally set the calculated flags in SPI_CS */ + bcm2835_wr(bs, BCM2835_SPI_CS, cs); +} + +static int chip_match_name(struct gpio_chip *chip, void *data) +{ + return !strcmp(chip->label, data); +} + +static int bcm2835_spi_setup(struct spi_device *spi) +{ + int err; + struct gpio_chip *chip; + /* + * sanity checking the native-chipselects + */ + if (spi->mode & SPI_NO_CS) + return 0; + if (gpio_is_valid(spi->cs_gpio)) + return 0; + if (spi->chip_select > 1) { + /* error in the case of native CS requested with CS > 1 + * officially there is a CS2, but it is not documented + * which GPIO is connected with that... + */ + dev_err(&spi->dev, + "setup: only two native chip-selects are supported\n"); + return -EINVAL; + } + /* now translate native cs to GPIO */ + + /* get the gpio chip for the base */ + chip = gpiochip_find("pinctrl-bcm2835", chip_match_name); + if (!chip) + return 0; + + /* and calculate the real CS */ + spi->cs_gpio = chip->base + 8 - spi->chip_select; + + /* and set up the "mode" and level */ + dev_info(&spi->dev, "setting up native-CS%i as GPIO %i\n", + spi->chip_select, spi->cs_gpio); + + /* set up GPIO as output and pull to the correct level */ + err = gpio_direction_output(spi->cs_gpio, + (spi->mode & SPI_CS_HIGH) ? 0 : 1); + if (err) { + dev_err(&spi->dev, + "could not set CS%i gpio %i as output: %i", + spi->chip_select, spi->cs_gpio, err); + return err; + } + /* the implementation of pinctrl-bcm2835 currently does not + * set the GPIO value when using gpio_direction_output + * so we are setting it here explicitly + */ + gpio_set_value(spi->cs_gpio, (spi->mode & SPI_CS_HIGH) ? 0 : 1); + + return 0; +} + +static int bcm2835_spi_probe(struct platform_device *pdev) +{ + struct spi_master *master; + struct bcm2835_spi *bs; + struct resource *res; + int err; + + master = spi_alloc_master(&pdev->dev, sizeof(*bs)); + if (!master) { + dev_err(&pdev->dev, "spi_alloc_master() failed\n"); + return -ENOMEM; + } + + platform_set_drvdata(pdev, master); + + master->mode_bits = BCM2835_SPI_MODE_BITS; + master->bits_per_word_mask = SPI_BPW_MASK(8); + master->num_chipselect = 3; + master->setup = bcm2835_spi_setup; + master->set_cs = bcm2835_spi_set_cs; + master->transfer_one = bcm2835_spi_transfer_one; + master->handle_err = bcm2835_spi_handle_err; + master->dev.of_node = pdev->dev.of_node; + + bs = spi_master_get_devdata(master); + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + bs->regs = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(bs->regs)) { + err = PTR_ERR(bs->regs); + goto out_master_put; + } + + bs->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(bs->clk)) { + err = PTR_ERR(bs->clk); + dev_err(&pdev->dev, "could not get clk: %d\n", err); + goto out_master_put; + } + + bs->irq = irq_of_parse_and_map(pdev->dev.of_node, 0); + if (bs->irq <= 0) { + dev_err(&pdev->dev, "could not get IRQ: %d\n", bs->irq); + err = bs->irq ? bs->irq : -ENODEV; + goto out_master_put; + } + + clk_prepare_enable(bs->clk); + + err = devm_request_irq(&pdev->dev, bs->irq, bcm2835_spi_interrupt, 0, + dev_name(&pdev->dev), master); + if (err) { + dev_err(&pdev->dev, "could not request IRQ: %d\n", err); + goto out_clk_disable; + } + + /* initialise the hardware with the default polarities */ + bcm2835_wr(bs, BCM2835_SPI_CS, + BCM2835_SPI_CS_CLEAR_RX | BCM2835_SPI_CS_CLEAR_TX); + + err = devm_spi_register_master(&pdev->dev, master); + if (err) { + dev_err(&pdev->dev, "could not register SPI master: %d\n", err); + goto out_clk_disable; + } + + return 0; + +out_clk_disable: + clk_disable_unprepare(bs->clk); +out_master_put: + spi_master_put(master); + return err; +} + +static int bcm2835_spi_remove(struct platform_device *pdev) +{ + struct spi_master *master = platform_get_drvdata(pdev); + struct bcm2835_spi *bs = spi_master_get_devdata(master); + + /* Clear FIFOs, and disable the HW block */ + bcm2835_wr(bs, BCM2835_SPI_CS, + BCM2835_SPI_CS_CLEAR_RX | BCM2835_SPI_CS_CLEAR_TX); + + clk_disable_unprepare(bs->clk); + + return 0; +} + +static const struct of_device_id bcm2835_spi_match[] = { + { .compatible = "brcm,bcm2835-spi", }, + {} +}; +MODULE_DEVICE_TABLE(of, bcm2835_spi_match); + +static struct platform_driver bcm2835_spi_driver = { + .driver = { + .name = DRV_NAME, + .of_match_table = bcm2835_spi_match, + }, + .probe = bcm2835_spi_probe, + .remove = bcm2835_spi_remove, +}; +module_platform_driver(bcm2835_spi_driver); + +MODULE_DESCRIPTION("SPI controller driver for Broadcom BCM2835"); +MODULE_AUTHOR("Chris Boot <bootc@bootc.net>"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/spi/spi-bcm53xx.c b/drivers/spi/spi-bcm53xx.c new file mode 100644 index 000000000..152055497 --- /dev/null +++ b/drivers/spi/spi-bcm53xx.c @@ -0,0 +1,299 @@ +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/delay.h> +#include <linux/bcma/bcma.h> +#include <linux/spi/spi.h> + +#include "spi-bcm53xx.h" + +#define BCM53XXSPI_MAX_SPI_BAUD 13500000 /* 216 MHz? */ + +/* The longest observed required wait was 19 ms */ +#define BCM53XXSPI_SPE_TIMEOUT_MS 80 + +struct bcm53xxspi { + struct bcma_device *core; + struct spi_master *master; + + size_t read_offset; +}; + +static inline u32 bcm53xxspi_read(struct bcm53xxspi *b53spi, u16 offset) +{ + return bcma_read32(b53spi->core, offset); +} + +static inline void bcm53xxspi_write(struct bcm53xxspi *b53spi, u16 offset, + u32 value) +{ + bcma_write32(b53spi->core, offset, value); +} + +static inline unsigned int bcm53xxspi_calc_timeout(size_t len) +{ + /* Do some magic calculation based on length and buad. Add 10% and 1. */ + return (len * 9000 / BCM53XXSPI_MAX_SPI_BAUD * 110 / 100) + 1; +} + +static int bcm53xxspi_wait(struct bcm53xxspi *b53spi, unsigned int timeout_ms) +{ + unsigned long deadline; + u32 tmp; + + /* SPE bit has to be 0 before we read MSPI STATUS */ + deadline = jiffies + msecs_to_jiffies(BCM53XXSPI_SPE_TIMEOUT_MS); + do { + tmp = bcm53xxspi_read(b53spi, B53SPI_MSPI_SPCR2); + if (!(tmp & B53SPI_MSPI_SPCR2_SPE)) + break; + udelay(5); + } while (!time_after_eq(jiffies, deadline)); + + if (tmp & B53SPI_MSPI_SPCR2_SPE) + goto spi_timeout; + + /* Check status */ + deadline = jiffies + msecs_to_jiffies(timeout_ms); + do { + tmp = bcm53xxspi_read(b53spi, B53SPI_MSPI_MSPI_STATUS); + if (tmp & B53SPI_MSPI_MSPI_STATUS_SPIF) { + bcm53xxspi_write(b53spi, B53SPI_MSPI_MSPI_STATUS, 0); + return 0; + } + + cpu_relax(); + udelay(100); + } while (!time_after_eq(jiffies, deadline)); + +spi_timeout: + bcm53xxspi_write(b53spi, B53SPI_MSPI_MSPI_STATUS, 0); + + pr_err("Timeout waiting for SPI to be ready!\n"); + + return -EBUSY; +} + +static void bcm53xxspi_buf_write(struct bcm53xxspi *b53spi, u8 *w_buf, + size_t len, bool cont) +{ + u32 tmp; + int i; + + for (i = 0; i < len; i++) { + /* Transmit Register File MSB */ + bcm53xxspi_write(b53spi, B53SPI_MSPI_TXRAM + 4 * (i * 2), + (unsigned int)w_buf[i]); + } + + for (i = 0; i < len; i++) { + tmp = B53SPI_CDRAM_CONT | B53SPI_CDRAM_PCS_DISABLE_ALL | + B53SPI_CDRAM_PCS_DSCK; + if (!cont && i == len - 1) + tmp &= ~B53SPI_CDRAM_CONT; + tmp &= ~0x1; + /* Command Register File */ + bcm53xxspi_write(b53spi, B53SPI_MSPI_CDRAM + 4 * i, tmp); + } + + /* Set queue pointers */ + bcm53xxspi_write(b53spi, B53SPI_MSPI_NEWQP, 0); + bcm53xxspi_write(b53spi, B53SPI_MSPI_ENDQP, len - 1); + + if (cont) + bcm53xxspi_write(b53spi, B53SPI_MSPI_WRITE_LOCK, 1); + + /* Start SPI transfer */ + tmp = bcm53xxspi_read(b53spi, B53SPI_MSPI_SPCR2); + tmp |= B53SPI_MSPI_SPCR2_SPE; + if (cont) + tmp |= B53SPI_MSPI_SPCR2_CONT_AFTER_CMD; + bcm53xxspi_write(b53spi, B53SPI_MSPI_SPCR2, tmp); + + /* Wait for SPI to finish */ + bcm53xxspi_wait(b53spi, bcm53xxspi_calc_timeout(len)); + + if (!cont) + bcm53xxspi_write(b53spi, B53SPI_MSPI_WRITE_LOCK, 0); + + b53spi->read_offset = len; +} + +static void bcm53xxspi_buf_read(struct bcm53xxspi *b53spi, u8 *r_buf, + size_t len, bool cont) +{ + u32 tmp; + int i; + + for (i = 0; i < b53spi->read_offset + len; i++) { + tmp = B53SPI_CDRAM_CONT | B53SPI_CDRAM_PCS_DISABLE_ALL | + B53SPI_CDRAM_PCS_DSCK; + if (!cont && i == b53spi->read_offset + len - 1) + tmp &= ~B53SPI_CDRAM_CONT; + tmp &= ~0x1; + /* Command Register File */ + bcm53xxspi_write(b53spi, B53SPI_MSPI_CDRAM + 4 * i, tmp); + } + + /* Set queue pointers */ + bcm53xxspi_write(b53spi, B53SPI_MSPI_NEWQP, 0); + bcm53xxspi_write(b53spi, B53SPI_MSPI_ENDQP, + b53spi->read_offset + len - 1); + + if (cont) + bcm53xxspi_write(b53spi, B53SPI_MSPI_WRITE_LOCK, 1); + + /* Start SPI transfer */ + tmp = bcm53xxspi_read(b53spi, B53SPI_MSPI_SPCR2); + tmp |= B53SPI_MSPI_SPCR2_SPE; + if (cont) + tmp |= B53SPI_MSPI_SPCR2_CONT_AFTER_CMD; + bcm53xxspi_write(b53spi, B53SPI_MSPI_SPCR2, tmp); + + /* Wait for SPI to finish */ + bcm53xxspi_wait(b53spi, bcm53xxspi_calc_timeout(len)); + + if (!cont) + bcm53xxspi_write(b53spi, B53SPI_MSPI_WRITE_LOCK, 0); + + for (i = 0; i < len; ++i) { + int offset = b53spi->read_offset + i; + + /* Data stored in the transmit register file LSB */ + r_buf[i] = (u8)bcm53xxspi_read(b53spi, B53SPI_MSPI_RXRAM + 4 * (1 + offset * 2)); + } + + b53spi->read_offset = 0; +} + +static int bcm53xxspi_transfer_one(struct spi_master *master, + struct spi_device *spi, + struct spi_transfer *t) +{ + struct bcm53xxspi *b53spi = spi_master_get_devdata(master); + u8 *buf; + size_t left; + + if (t->tx_buf) { + buf = (u8 *)t->tx_buf; + left = t->len; + while (left) { + size_t to_write = min_t(size_t, 16, left); + bool cont = left - to_write > 0; + + bcm53xxspi_buf_write(b53spi, buf, to_write, cont); + left -= to_write; + buf += to_write; + } + } + + if (t->rx_buf) { + buf = (u8 *)t->rx_buf; + left = t->len; + while (left) { + size_t to_read = min_t(size_t, 16 - b53spi->read_offset, + left); + bool cont = left - to_read > 0; + + bcm53xxspi_buf_read(b53spi, buf, to_read, cont); + left -= to_read; + buf += to_read; + } + } + + return 0; +} + +/************************************************** + * BCMA + **************************************************/ + +static struct spi_board_info bcm53xx_info = { + .modalias = "bcm53xxspiflash", +}; + +static const struct bcma_device_id bcm53xxspi_bcma_tbl[] = { + BCMA_CORE(BCMA_MANUF_BCM, BCMA_CORE_NS_QSPI, BCMA_ANY_REV, BCMA_ANY_CLASS), + {}, +}; +MODULE_DEVICE_TABLE(bcma, bcm53xxspi_bcma_tbl); + +static int bcm53xxspi_bcma_probe(struct bcma_device *core) +{ + struct bcm53xxspi *b53spi; + struct spi_master *master; + int err; + + if (core->bus->drv_cc.core->id.rev != 42) { + pr_err("SPI on SoC with unsupported ChipCommon rev\n"); + return -ENOTSUPP; + } + + master = spi_alloc_master(&core->dev, sizeof(*b53spi)); + if (!master) + return -ENOMEM; + + b53spi = spi_master_get_devdata(master); + b53spi->master = master; + b53spi->core = core; + + master->transfer_one = bcm53xxspi_transfer_one; + + bcma_set_drvdata(core, b53spi); + + err = devm_spi_register_master(&core->dev, master); + if (err) { + spi_master_put(master); + bcma_set_drvdata(core, NULL); + goto out; + } + + /* Broadcom SoCs (at least with the CC rev 42) use SPI for flash only */ + spi_new_device(master, &bcm53xx_info); + +out: + return err; +} + +static void bcm53xxspi_bcma_remove(struct bcma_device *core) +{ + struct bcm53xxspi *b53spi = bcma_get_drvdata(core); + + spi_unregister_master(b53spi->master); +} + +static struct bcma_driver bcm53xxspi_bcma_driver = { + .name = KBUILD_MODNAME, + .id_table = bcm53xxspi_bcma_tbl, + .probe = bcm53xxspi_bcma_probe, + .remove = bcm53xxspi_bcma_remove, +}; + +/************************************************** + * Init & exit + **************************************************/ + +static int __init bcm53xxspi_module_init(void) +{ + int err = 0; + + err = bcma_driver_register(&bcm53xxspi_bcma_driver); + if (err) + pr_err("Failed to register bcma driver: %d\n", err); + + return err; +} + +static void __exit bcm53xxspi_module_exit(void) +{ + bcma_driver_unregister(&bcm53xxspi_bcma_driver); +} + +module_init(bcm53xxspi_module_init); +module_exit(bcm53xxspi_module_exit); + +MODULE_DESCRIPTION("Broadcom BCM53xx SPI Controller driver"); +MODULE_AUTHOR("RafaÅ‚ MiÅ‚ecki <zajec5@gmail.com>"); +MODULE_LICENSE("GPL"); diff --git a/drivers/spi/spi-bcm53xx.h b/drivers/spi/spi-bcm53xx.h new file mode 100644 index 000000000..73575dfe6 --- /dev/null +++ b/drivers/spi/spi-bcm53xx.h @@ -0,0 +1,72 @@ +#ifndef SPI_BCM53XX_H +#define SPI_BCM53XX_H + +#define B53SPI_BSPI_REVISION_ID 0x000 +#define B53SPI_BSPI_SCRATCH 0x004 +#define B53SPI_BSPI_MAST_N_BOOT_CTRL 0x008 +#define B53SPI_BSPI_BUSY_STATUS 0x00c +#define B53SPI_BSPI_INTR_STATUS 0x010 +#define B53SPI_BSPI_B0_STATUS 0x014 +#define B53SPI_BSPI_B0_CTRL 0x018 +#define B53SPI_BSPI_B1_STATUS 0x01c +#define B53SPI_BSPI_B1_CTRL 0x020 +#define B53SPI_BSPI_STRAP_OVERRIDE_CTRL 0x024 +#define B53SPI_BSPI_FLEX_MODE_ENABLE 0x028 +#define B53SPI_BSPI_BITS_PER_CYCLE 0x02c +#define B53SPI_BSPI_BITS_PER_PHASE 0x030 +#define B53SPI_BSPI_CMD_AND_MODE_BYTE 0x034 +#define B53SPI_BSPI_BSPI_FLASH_UPPER_ADDR_BYTE 0x038 +#define B53SPI_BSPI_BSPI_XOR_VALUE 0x03c +#define B53SPI_BSPI_BSPI_XOR_ENABLE 0x040 +#define B53SPI_BSPI_BSPI_PIO_MODE_ENABLE 0x044 +#define B53SPI_BSPI_BSPI_PIO_IODIR 0x048 +#define B53SPI_BSPI_BSPI_PIO_DATA 0x04c + +/* RAF */ +#define B53SPI_RAF_START_ADDR 0x100 +#define B53SPI_RAF_NUM_WORDS 0x104 +#define B53SPI_RAF_CTRL 0x108 +#define B53SPI_RAF_FULLNESS 0x10c +#define B53SPI_RAF_WATERMARK 0x110 +#define B53SPI_RAF_STATUS 0x114 +#define B53SPI_RAF_READ_DATA 0x118 +#define B53SPI_RAF_WORD_CNT 0x11c +#define B53SPI_RAF_CURR_ADDR 0x120 + +/* MSPI */ +#define B53SPI_MSPI_SPCR0_LSB 0x200 +#define B53SPI_MSPI_SPCR0_MSB 0x204 +#define B53SPI_MSPI_SPCR1_LSB 0x208 +#define B53SPI_MSPI_SPCR1_MSB 0x20c +#define B53SPI_MSPI_NEWQP 0x210 +#define B53SPI_MSPI_ENDQP 0x214 +#define B53SPI_MSPI_SPCR2 0x218 +#define B53SPI_MSPI_SPCR2_SPE 0x00000040 +#define B53SPI_MSPI_SPCR2_CONT_AFTER_CMD 0x00000080 +#define B53SPI_MSPI_MSPI_STATUS 0x220 +#define B53SPI_MSPI_MSPI_STATUS_SPIF 0x00000001 +#define B53SPI_MSPI_CPTQP 0x224 +#define B53SPI_MSPI_TXRAM 0x240 /* 32 registers, up to 0x2b8 */ +#define B53SPI_MSPI_RXRAM 0x2c0 /* 32 registers, up to 0x33c */ +#define B53SPI_MSPI_CDRAM 0x340 /* 16 registers, up to 0x37c */ +#define B53SPI_CDRAM_PCS_PCS0 0x00000001 +#define B53SPI_CDRAM_PCS_PCS1 0x00000002 +#define B53SPI_CDRAM_PCS_PCS2 0x00000004 +#define B53SPI_CDRAM_PCS_PCS3 0x00000008 +#define B53SPI_CDRAM_PCS_DISABLE_ALL 0x0000000f +#define B53SPI_CDRAM_PCS_DSCK 0x00000010 +#define B53SPI_CDRAM_BITSE 0x00000040 +#define B53SPI_CDRAM_CONT 0x00000080 +#define B53SPI_MSPI_WRITE_LOCK 0x380 +#define B53SPI_MSPI_DISABLE_FLUSH_GEN 0x384 + +/* Interrupt */ +#define B53SPI_INTR_RAF_LR_FULLNESS_REACHED 0x3a0 +#define B53SPI_INTR_RAF_LR_TRUNCATED 0x3a4 +#define B53SPI_INTR_RAF_LR_IMPATIENT 0x3a8 +#define B53SPI_INTR_RAF_LR_SESSION_DONE 0x3ac +#define B53SPI_INTR_RAF_LR_OVERREAD 0x3b0 +#define B53SPI_INTR_MSPI_DONE 0x3b4 +#define B53SPI_INTR_MSPI_HALT_SET_TRANSACTION_DONE 0x3b8 + +#endif /* SPI_BCM53XX_H */ diff --git a/drivers/spi/spi-bcm63xx-hsspi.c b/drivers/spi/spi-bcm63xx-hsspi.c new file mode 100644 index 000000000..f5ca6dc3a --- /dev/null +++ b/drivers/spi/spi-bcm63xx-hsspi.c @@ -0,0 +1,473 @@ +/* + * Broadcom BCM63XX High Speed SPI Controller driver + * + * Copyright 2000-2010 Broadcom Corporation + * Copyright 2012-2013 Jonas Gorski <jogo@openwrt.org> + * + * Licensed under the GNU/GPL. See COPYING for details. + */ + +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/io.h> +#include <linux/clk.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/delay.h> +#include <linux/dma-mapping.h> +#include <linux/err.h> +#include <linux/interrupt.h> +#include <linux/spi/spi.h> +#include <linux/mutex.h> + +#define HSSPI_GLOBAL_CTRL_REG 0x0 +#define GLOBAL_CTRL_CS_POLARITY_SHIFT 0 +#define GLOBAL_CTRL_CS_POLARITY_MASK 0x000000ff +#define GLOBAL_CTRL_PLL_CLK_CTRL_SHIFT 8 +#define GLOBAL_CTRL_PLL_CLK_CTRL_MASK 0x0000ff00 +#define GLOBAL_CTRL_CLK_GATE_SSOFF BIT(16) +#define GLOBAL_CTRL_CLK_POLARITY BIT(17) +#define GLOBAL_CTRL_MOSI_IDLE BIT(18) + +#define HSSPI_GLOBAL_EXT_TRIGGER_REG 0x4 + +#define HSSPI_INT_STATUS_REG 0x8 +#define HSSPI_INT_STATUS_MASKED_REG 0xc +#define HSSPI_INT_MASK_REG 0x10 + +#define HSSPI_PINGx_CMD_DONE(i) BIT((i * 8) + 0) +#define HSSPI_PINGx_RX_OVER(i) BIT((i * 8) + 1) +#define HSSPI_PINGx_TX_UNDER(i) BIT((i * 8) + 2) +#define HSSPI_PINGx_POLL_TIMEOUT(i) BIT((i * 8) + 3) +#define HSSPI_PINGx_CTRL_INVAL(i) BIT((i * 8) + 4) + +#define HSSPI_INT_CLEAR_ALL 0xff001f1f + +#define HSSPI_PINGPONG_COMMAND_REG(x) (0x80 + (x) * 0x40) +#define PINGPONG_CMD_COMMAND_MASK 0xf +#define PINGPONG_COMMAND_NOOP 0 +#define PINGPONG_COMMAND_START_NOW 1 +#define PINGPONG_COMMAND_START_TRIGGER 2 +#define PINGPONG_COMMAND_HALT 3 +#define PINGPONG_COMMAND_FLUSH 4 +#define PINGPONG_CMD_PROFILE_SHIFT 8 +#define PINGPONG_CMD_SS_SHIFT 12 + +#define HSSPI_PINGPONG_STATUS_REG(x) (0x84 + (x) * 0x40) + +#define HSSPI_PROFILE_CLK_CTRL_REG(x) (0x100 + (x) * 0x20) +#define CLK_CTRL_FREQ_CTRL_MASK 0x0000ffff +#define CLK_CTRL_SPI_CLK_2X_SEL BIT(14) +#define CLK_CTRL_ACCUM_RST_ON_LOOP BIT(15) + +#define HSSPI_PROFILE_SIGNAL_CTRL_REG(x) (0x104 + (x) * 0x20) +#define SIGNAL_CTRL_LATCH_RISING BIT(12) +#define SIGNAL_CTRL_LAUNCH_RISING BIT(13) +#define SIGNAL_CTRL_ASYNC_INPUT_PATH BIT(16) + +#define HSSPI_PROFILE_MODE_CTRL_REG(x) (0x108 + (x) * 0x20) +#define MODE_CTRL_MULTIDATA_RD_STRT_SHIFT 8 +#define MODE_CTRL_MULTIDATA_WR_STRT_SHIFT 12 +#define MODE_CTRL_MULTIDATA_RD_SIZE_SHIFT 16 +#define MODE_CTRL_MULTIDATA_WR_SIZE_SHIFT 18 +#define MODE_CTRL_MODE_3WIRE BIT(20) +#define MODE_CTRL_PREPENDBYTE_CNT_SHIFT 24 + +#define HSSPI_FIFO_REG(x) (0x200 + (x) * 0x200) + + +#define HSSPI_OP_CODE_SHIFT 13 +#define HSSPI_OP_SLEEP (0 << HSSPI_OP_CODE_SHIFT) +#define HSSPI_OP_READ_WRITE (1 << HSSPI_OP_CODE_SHIFT) +#define HSSPI_OP_WRITE (2 << HSSPI_OP_CODE_SHIFT) +#define HSSPI_OP_READ (3 << HSSPI_OP_CODE_SHIFT) +#define HSSPI_OP_SETIRQ (4 << HSSPI_OP_CODE_SHIFT) + +#define HSSPI_BUFFER_LEN 512 +#define HSSPI_OPCODE_LEN 2 + +#define HSSPI_MAX_PREPEND_LEN 15 + +#define HSSPI_MAX_SYNC_CLOCK 30000000 + +#define HSSPI_BUS_NUM 1 /* 0 is legacy SPI */ + +struct bcm63xx_hsspi { + struct completion done; + struct mutex bus_mutex; + + struct platform_device *pdev; + struct clk *clk; + void __iomem *regs; + u8 __iomem *fifo; + + u32 speed_hz; + u8 cs_polarity; +}; + +static void bcm63xx_hsspi_set_cs(struct bcm63xx_hsspi *bs, unsigned cs, + bool active) +{ + u32 reg; + + mutex_lock(&bs->bus_mutex); + reg = __raw_readl(bs->regs + HSSPI_GLOBAL_CTRL_REG); + + reg &= ~BIT(cs); + if (active == !(bs->cs_polarity & BIT(cs))) + reg |= BIT(cs); + + __raw_writel(reg, bs->regs + HSSPI_GLOBAL_CTRL_REG); + mutex_unlock(&bs->bus_mutex); +} + +static void bcm63xx_hsspi_set_clk(struct bcm63xx_hsspi *bs, + struct spi_device *spi, int hz) +{ + unsigned profile = spi->chip_select; + u32 reg; + + reg = DIV_ROUND_UP(2048, DIV_ROUND_UP(bs->speed_hz, hz)); + __raw_writel(CLK_CTRL_ACCUM_RST_ON_LOOP | reg, + bs->regs + HSSPI_PROFILE_CLK_CTRL_REG(profile)); + + reg = __raw_readl(bs->regs + HSSPI_PROFILE_SIGNAL_CTRL_REG(profile)); + if (hz > HSSPI_MAX_SYNC_CLOCK) + reg |= SIGNAL_CTRL_ASYNC_INPUT_PATH; + else + reg &= ~SIGNAL_CTRL_ASYNC_INPUT_PATH; + __raw_writel(reg, bs->regs + HSSPI_PROFILE_SIGNAL_CTRL_REG(profile)); + + mutex_lock(&bs->bus_mutex); + /* setup clock polarity */ + reg = __raw_readl(bs->regs + HSSPI_GLOBAL_CTRL_REG); + reg &= ~GLOBAL_CTRL_CLK_POLARITY; + if (spi->mode & SPI_CPOL) + reg |= GLOBAL_CTRL_CLK_POLARITY; + __raw_writel(reg, bs->regs + HSSPI_GLOBAL_CTRL_REG); + mutex_unlock(&bs->bus_mutex); +} + +static int bcm63xx_hsspi_do_txrx(struct spi_device *spi, struct spi_transfer *t) +{ + struct bcm63xx_hsspi *bs = spi_master_get_devdata(spi->master); + unsigned chip_select = spi->chip_select; + u16 opcode = 0; + int pending = t->len; + int step_size = HSSPI_BUFFER_LEN; + const u8 *tx = t->tx_buf; + u8 *rx = t->rx_buf; + + bcm63xx_hsspi_set_clk(bs, spi, t->speed_hz); + bcm63xx_hsspi_set_cs(bs, spi->chip_select, true); + + if (tx && rx) + opcode = HSSPI_OP_READ_WRITE; + else if (tx) + opcode = HSSPI_OP_WRITE; + else if (rx) + opcode = HSSPI_OP_READ; + + if (opcode != HSSPI_OP_READ) + step_size -= HSSPI_OPCODE_LEN; + + __raw_writel(0 << MODE_CTRL_PREPENDBYTE_CNT_SHIFT | + 2 << MODE_CTRL_MULTIDATA_WR_STRT_SHIFT | + 2 << MODE_CTRL_MULTIDATA_RD_STRT_SHIFT | 0xff, + bs->regs + HSSPI_PROFILE_MODE_CTRL_REG(chip_select)); + + while (pending > 0) { + int curr_step = min_t(int, step_size, pending); + + reinit_completion(&bs->done); + if (tx) { + memcpy_toio(bs->fifo + HSSPI_OPCODE_LEN, tx, curr_step); + tx += curr_step; + } + + __raw_writew(opcode | curr_step, bs->fifo); + + /* enable interrupt */ + __raw_writel(HSSPI_PINGx_CMD_DONE(0), + bs->regs + HSSPI_INT_MASK_REG); + + /* start the transfer */ + __raw_writel(!chip_select << PINGPONG_CMD_SS_SHIFT | + chip_select << PINGPONG_CMD_PROFILE_SHIFT | + PINGPONG_COMMAND_START_NOW, + bs->regs + HSSPI_PINGPONG_COMMAND_REG(0)); + + if (wait_for_completion_timeout(&bs->done, HZ) == 0) { + dev_err(&bs->pdev->dev, "transfer timed out!\n"); + return -ETIMEDOUT; + } + + if (rx) { + memcpy_fromio(rx, bs->fifo, curr_step); + rx += curr_step; + } + + pending -= curr_step; + } + + return 0; +} + +static int bcm63xx_hsspi_setup(struct spi_device *spi) +{ + struct bcm63xx_hsspi *bs = spi_master_get_devdata(spi->master); + u32 reg; + + reg = __raw_readl(bs->regs + + HSSPI_PROFILE_SIGNAL_CTRL_REG(spi->chip_select)); + reg &= ~(SIGNAL_CTRL_LAUNCH_RISING | SIGNAL_CTRL_LATCH_RISING); + if (spi->mode & SPI_CPHA) + reg |= SIGNAL_CTRL_LAUNCH_RISING; + else + reg |= SIGNAL_CTRL_LATCH_RISING; + __raw_writel(reg, bs->regs + + HSSPI_PROFILE_SIGNAL_CTRL_REG(spi->chip_select)); + + mutex_lock(&bs->bus_mutex); + reg = __raw_readl(bs->regs + HSSPI_GLOBAL_CTRL_REG); + + /* only change actual polarities if there is no transfer */ + if ((reg & GLOBAL_CTRL_CS_POLARITY_MASK) == bs->cs_polarity) { + if (spi->mode & SPI_CS_HIGH) + reg |= BIT(spi->chip_select); + else + reg &= ~BIT(spi->chip_select); + __raw_writel(reg, bs->regs + HSSPI_GLOBAL_CTRL_REG); + } + + if (spi->mode & SPI_CS_HIGH) + bs->cs_polarity |= BIT(spi->chip_select); + else + bs->cs_polarity &= ~BIT(spi->chip_select); + + mutex_unlock(&bs->bus_mutex); + + return 0; +} + +static int bcm63xx_hsspi_transfer_one(struct spi_master *master, + struct spi_message *msg) +{ + struct bcm63xx_hsspi *bs = spi_master_get_devdata(master); + struct spi_transfer *t; + struct spi_device *spi = msg->spi; + int status = -EINVAL; + int dummy_cs; + u32 reg; + + /* This controller does not support keeping CS active during idle. + * To work around this, we use the following ugly hack: + * + * a. Invert the target chip select's polarity so it will be active. + * b. Select a "dummy" chip select to use as the hardware target. + * c. Invert the dummy chip select's polarity so it will be inactive + * during the actual transfers. + * d. Tell the hardware to send to the dummy chip select. Thanks to + * the multiplexed nature of SPI the actual target will receive + * the transfer and we see its response. + * + * e. At the end restore the polarities again to their default values. + */ + + dummy_cs = !spi->chip_select; + bcm63xx_hsspi_set_cs(bs, dummy_cs, true); + + list_for_each_entry(t, &msg->transfers, transfer_list) { + status = bcm63xx_hsspi_do_txrx(spi, t); + if (status) + break; + + msg->actual_length += t->len; + + if (t->delay_usecs) + udelay(t->delay_usecs); + + if (t->cs_change) + bcm63xx_hsspi_set_cs(bs, spi->chip_select, false); + } + + mutex_lock(&bs->bus_mutex); + reg = __raw_readl(bs->regs + HSSPI_GLOBAL_CTRL_REG); + reg &= ~GLOBAL_CTRL_CS_POLARITY_MASK; + reg |= bs->cs_polarity; + __raw_writel(reg, bs->regs + HSSPI_GLOBAL_CTRL_REG); + mutex_unlock(&bs->bus_mutex); + + msg->status = status; + spi_finalize_current_message(master); + + return 0; +} + +static irqreturn_t bcm63xx_hsspi_interrupt(int irq, void *dev_id) +{ + struct bcm63xx_hsspi *bs = (struct bcm63xx_hsspi *)dev_id; + + if (__raw_readl(bs->regs + HSSPI_INT_STATUS_MASKED_REG) == 0) + return IRQ_NONE; + + __raw_writel(HSSPI_INT_CLEAR_ALL, bs->regs + HSSPI_INT_STATUS_REG); + __raw_writel(0, bs->regs + HSSPI_INT_MASK_REG); + + complete(&bs->done); + + return IRQ_HANDLED; +} + +static int bcm63xx_hsspi_probe(struct platform_device *pdev) +{ + struct spi_master *master; + struct bcm63xx_hsspi *bs; + struct resource *res_mem; + void __iomem *regs; + struct device *dev = &pdev->dev; + struct clk *clk; + int irq, ret; + u32 reg, rate; + + irq = platform_get_irq(pdev, 0); + if (irq < 0) { + dev_err(dev, "no irq\n"); + return -ENXIO; + } + + res_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); + regs = devm_ioremap_resource(dev, res_mem); + if (IS_ERR(regs)) + return PTR_ERR(regs); + + clk = devm_clk_get(dev, "hsspi"); + + if (IS_ERR(clk)) + return PTR_ERR(clk); + + rate = clk_get_rate(clk); + if (!rate) + return -EINVAL; + + ret = clk_prepare_enable(clk); + if (ret) + return ret; + + master = spi_alloc_master(&pdev->dev, sizeof(*bs)); + if (!master) { + ret = -ENOMEM; + goto out_disable_clk; + } + + bs = spi_master_get_devdata(master); + bs->pdev = pdev; + bs->clk = clk; + bs->regs = regs; + bs->speed_hz = rate; + bs->fifo = (u8 __iomem *)(bs->regs + HSSPI_FIFO_REG(0)); + + mutex_init(&bs->bus_mutex); + init_completion(&bs->done); + + master->bus_num = HSSPI_BUS_NUM; + master->num_chipselect = 8; + master->setup = bcm63xx_hsspi_setup; + master->transfer_one_message = bcm63xx_hsspi_transfer_one; + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH; + master->bits_per_word_mask = SPI_BPW_MASK(8); + master->auto_runtime_pm = true; + + platform_set_drvdata(pdev, master); + + /* Initialize the hardware */ + __raw_writel(0, bs->regs + HSSPI_INT_MASK_REG); + + /* clean up any pending interrupts */ + __raw_writel(HSSPI_INT_CLEAR_ALL, bs->regs + HSSPI_INT_STATUS_REG); + + /* read out default CS polarities */ + reg = __raw_readl(bs->regs + HSSPI_GLOBAL_CTRL_REG); + bs->cs_polarity = reg & GLOBAL_CTRL_CS_POLARITY_MASK; + __raw_writel(reg | GLOBAL_CTRL_CLK_GATE_SSOFF, + bs->regs + HSSPI_GLOBAL_CTRL_REG); + + ret = devm_request_irq(dev, irq, bcm63xx_hsspi_interrupt, IRQF_SHARED, + pdev->name, bs); + + if (ret) + goto out_put_master; + + /* register and we are done */ + ret = devm_spi_register_master(dev, master); + if (ret) + goto out_put_master; + + return 0; + +out_put_master: + spi_master_put(master); +out_disable_clk: + clk_disable_unprepare(clk); + return ret; +} + + +static int bcm63xx_hsspi_remove(struct platform_device *pdev) +{ + struct spi_master *master = platform_get_drvdata(pdev); + struct bcm63xx_hsspi *bs = spi_master_get_devdata(master); + + /* reset the hardware and block queue progress */ + __raw_writel(0, bs->regs + HSSPI_INT_MASK_REG); + clk_disable_unprepare(bs->clk); + + return 0; +} + +#ifdef CONFIG_PM_SLEEP +static int bcm63xx_hsspi_suspend(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct bcm63xx_hsspi *bs = spi_master_get_devdata(master); + + spi_master_suspend(master); + clk_disable_unprepare(bs->clk); + + return 0; +} + +static int bcm63xx_hsspi_resume(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct bcm63xx_hsspi *bs = spi_master_get_devdata(master); + int ret; + + ret = clk_prepare_enable(bs->clk); + if (ret) + return ret; + + spi_master_resume(master); + + return 0; +} +#endif + +static SIMPLE_DEV_PM_OPS(bcm63xx_hsspi_pm_ops, bcm63xx_hsspi_suspend, + bcm63xx_hsspi_resume); + +static struct platform_driver bcm63xx_hsspi_driver = { + .driver = { + .name = "bcm63xx-hsspi", + .pm = &bcm63xx_hsspi_pm_ops, + }, + .probe = bcm63xx_hsspi_probe, + .remove = bcm63xx_hsspi_remove, +}; + +module_platform_driver(bcm63xx_hsspi_driver); + +MODULE_ALIAS("platform:bcm63xx_hsspi"); +MODULE_DESCRIPTION("Broadcom BCM63xx High Speed SPI Controller driver"); +MODULE_AUTHOR("Jonas Gorski <jogo@openwrt.org>"); +MODULE_LICENSE("GPL"); diff --git a/drivers/spi/spi-bcm63xx.c b/drivers/spi/spi-bcm63xx.c new file mode 100644 index 000000000..e73e2b052 --- /dev/null +++ b/drivers/spi/spi-bcm63xx.c @@ -0,0 +1,480 @@ +/* + * Broadcom BCM63xx SPI controller support + * + * Copyright (C) 2009-2012 Florian Fainelli <florian@openwrt.org> + * Copyright (C) 2010 Tanguy Bouzeloc <tanguy.bouzeloc@efixo.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/kernel.h> +#include <linux/clk.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/delay.h> +#include <linux/interrupt.h> +#include <linux/spi/spi.h> +#include <linux/completion.h> +#include <linux/err.h> +#include <linux/pm_runtime.h> + +#include <bcm63xx_dev_spi.h> + +#define BCM63XX_SPI_MAX_PREPEND 15 + +struct bcm63xx_spi { + struct completion done; + + void __iomem *regs; + int irq; + + /* Platform data */ + unsigned fifo_size; + unsigned int msg_type_shift; + unsigned int msg_ctl_width; + + /* data iomem */ + u8 __iomem *tx_io; + const u8 __iomem *rx_io; + + struct clk *clk; + struct platform_device *pdev; +}; + +static inline u8 bcm_spi_readb(struct bcm63xx_spi *bs, + unsigned int offset) +{ + return bcm_readb(bs->regs + bcm63xx_spireg(offset)); +} + +static inline u16 bcm_spi_readw(struct bcm63xx_spi *bs, + unsigned int offset) +{ + return bcm_readw(bs->regs + bcm63xx_spireg(offset)); +} + +static inline void bcm_spi_writeb(struct bcm63xx_spi *bs, + u8 value, unsigned int offset) +{ + bcm_writeb(value, bs->regs + bcm63xx_spireg(offset)); +} + +static inline void bcm_spi_writew(struct bcm63xx_spi *bs, + u16 value, unsigned int offset) +{ + bcm_writew(value, bs->regs + bcm63xx_spireg(offset)); +} + +static const unsigned bcm63xx_spi_freq_table[SPI_CLK_MASK][2] = { + { 20000000, SPI_CLK_20MHZ }, + { 12500000, SPI_CLK_12_50MHZ }, + { 6250000, SPI_CLK_6_250MHZ }, + { 3125000, SPI_CLK_3_125MHZ }, + { 1563000, SPI_CLK_1_563MHZ }, + { 781000, SPI_CLK_0_781MHZ }, + { 391000, SPI_CLK_0_391MHZ } +}; + +static void bcm63xx_spi_setup_transfer(struct spi_device *spi, + struct spi_transfer *t) +{ + struct bcm63xx_spi *bs = spi_master_get_devdata(spi->master); + u8 clk_cfg, reg; + int i; + + /* Find the closest clock configuration */ + for (i = 0; i < SPI_CLK_MASK; i++) { + if (t->speed_hz >= bcm63xx_spi_freq_table[i][0]) { + clk_cfg = bcm63xx_spi_freq_table[i][1]; + break; + } + } + + /* No matching configuration found, default to lowest */ + if (i == SPI_CLK_MASK) + clk_cfg = SPI_CLK_0_391MHZ; + + /* clear existing clock configuration bits of the register */ + reg = bcm_spi_readb(bs, SPI_CLK_CFG); + reg &= ~SPI_CLK_MASK; + reg |= clk_cfg; + + bcm_spi_writeb(bs, reg, SPI_CLK_CFG); + dev_dbg(&spi->dev, "Setting clock register to %02x (hz %d)\n", + clk_cfg, t->speed_hz); +} + +/* the spi->mode bits understood by this driver: */ +#define MODEBITS (SPI_CPOL | SPI_CPHA) + +static int bcm63xx_txrx_bufs(struct spi_device *spi, struct spi_transfer *first, + unsigned int num_transfers) +{ + struct bcm63xx_spi *bs = spi_master_get_devdata(spi->master); + u16 msg_ctl; + u16 cmd; + u8 rx_tail; + unsigned int i, timeout = 0, prepend_len = 0, len = 0; + struct spi_transfer *t = first; + bool do_rx = false; + bool do_tx = false; + + /* Disable the CMD_DONE interrupt */ + bcm_spi_writeb(bs, 0, SPI_INT_MASK); + + dev_dbg(&spi->dev, "txrx: tx %p, rx %p, len %d\n", + t->tx_buf, t->rx_buf, t->len); + + if (num_transfers > 1 && t->tx_buf && t->len <= BCM63XX_SPI_MAX_PREPEND) + prepend_len = t->len; + + /* prepare the buffer */ + for (i = 0; i < num_transfers; i++) { + if (t->tx_buf) { + do_tx = true; + memcpy_toio(bs->tx_io + len, t->tx_buf, t->len); + + /* don't prepend more than one tx */ + if (t != first) + prepend_len = 0; + } + + if (t->rx_buf) { + do_rx = true; + /* prepend is half-duplex write only */ + if (t == first) + prepend_len = 0; + } + + len += t->len; + + t = list_entry(t->transfer_list.next, struct spi_transfer, + transfer_list); + } + + reinit_completion(&bs->done); + + /* Fill in the Message control register */ + msg_ctl = (len << SPI_BYTE_CNT_SHIFT); + + if (do_rx && do_tx && prepend_len == 0) + msg_ctl |= (SPI_FD_RW << bs->msg_type_shift); + else if (do_rx) + msg_ctl |= (SPI_HD_R << bs->msg_type_shift); + else if (do_tx) + msg_ctl |= (SPI_HD_W << bs->msg_type_shift); + + switch (bs->msg_ctl_width) { + case 8: + bcm_spi_writeb(bs, msg_ctl, SPI_MSG_CTL); + break; + case 16: + bcm_spi_writew(bs, msg_ctl, SPI_MSG_CTL); + break; + } + + /* Issue the transfer */ + cmd = SPI_CMD_START_IMMEDIATE; + cmd |= (prepend_len << SPI_CMD_PREPEND_BYTE_CNT_SHIFT); + cmd |= (spi->chip_select << SPI_CMD_DEVICE_ID_SHIFT); + bcm_spi_writew(bs, cmd, SPI_CMD); + + /* Enable the CMD_DONE interrupt */ + bcm_spi_writeb(bs, SPI_INTR_CMD_DONE, SPI_INT_MASK); + + timeout = wait_for_completion_timeout(&bs->done, HZ); + if (!timeout) + return -ETIMEDOUT; + + if (!do_rx) + return 0; + + len = 0; + t = first; + /* Read out all the data */ + for (i = 0; i < num_transfers; i++) { + if (t->rx_buf) + memcpy_fromio(t->rx_buf, bs->rx_io + len, t->len); + + if (t != first || prepend_len == 0) + len += t->len; + + t = list_entry(t->transfer_list.next, struct spi_transfer, + transfer_list); + } + + return 0; +} + +static int bcm63xx_spi_transfer_one(struct spi_master *master, + struct spi_message *m) +{ + struct bcm63xx_spi *bs = spi_master_get_devdata(master); + struct spi_transfer *t, *first = NULL; + struct spi_device *spi = m->spi; + int status = 0; + unsigned int n_transfers = 0, total_len = 0; + bool can_use_prepend = false; + + /* + * This SPI controller does not support keeping CS active after a + * transfer. + * Work around this by merging as many transfers we can into one big + * full-duplex transfers. + */ + list_for_each_entry(t, &m->transfers, transfer_list) { + if (!first) + first = t; + + n_transfers++; + total_len += t->len; + + if (n_transfers == 2 && !first->rx_buf && !t->tx_buf && + first->len <= BCM63XX_SPI_MAX_PREPEND) + can_use_prepend = true; + else if (can_use_prepend && t->tx_buf) + can_use_prepend = false; + + /* we can only transfer one fifo worth of data */ + if ((can_use_prepend && + total_len > (bs->fifo_size + BCM63XX_SPI_MAX_PREPEND)) || + (!can_use_prepend && total_len > bs->fifo_size)) { + dev_err(&spi->dev, "unable to do transfers larger than FIFO size (%i > %i)\n", + total_len, bs->fifo_size); + status = -EINVAL; + goto exit; + } + + /* all combined transfers have to have the same speed */ + if (t->speed_hz != first->speed_hz) { + dev_err(&spi->dev, "unable to change speed between transfers\n"); + status = -EINVAL; + goto exit; + } + + /* CS will be deasserted directly after transfer */ + if (t->delay_usecs) { + dev_err(&spi->dev, "unable to keep CS asserted after transfer\n"); + status = -EINVAL; + goto exit; + } + + if (t->cs_change || + list_is_last(&t->transfer_list, &m->transfers)) { + /* configure adapter for a new transfer */ + bcm63xx_spi_setup_transfer(spi, first); + + /* send the data */ + status = bcm63xx_txrx_bufs(spi, first, n_transfers); + if (status) + goto exit; + + m->actual_length += total_len; + + first = NULL; + n_transfers = 0; + total_len = 0; + can_use_prepend = false; + } + } +exit: + m->status = status; + spi_finalize_current_message(master); + + return 0; +} + +/* This driver supports single master mode only. Hence + * CMD_DONE is the only interrupt we care about + */ +static irqreturn_t bcm63xx_spi_interrupt(int irq, void *dev_id) +{ + struct spi_master *master = (struct spi_master *)dev_id; + struct bcm63xx_spi *bs = spi_master_get_devdata(master); + u8 intr; + + /* Read interupts and clear them immediately */ + intr = bcm_spi_readb(bs, SPI_INT_STATUS); + bcm_spi_writeb(bs, SPI_INTR_CLEAR_ALL, SPI_INT_STATUS); + bcm_spi_writeb(bs, 0, SPI_INT_MASK); + + /* A transfer completed */ + if (intr & SPI_INTR_CMD_DONE) + complete(&bs->done); + + return IRQ_HANDLED; +} + + +static int bcm63xx_spi_probe(struct platform_device *pdev) +{ + struct resource *r; + struct device *dev = &pdev->dev; + struct bcm63xx_spi_pdata *pdata = dev_get_platdata(&pdev->dev); + int irq; + struct spi_master *master; + struct clk *clk; + struct bcm63xx_spi *bs; + int ret; + + irq = platform_get_irq(pdev, 0); + if (irq < 0) { + dev_err(dev, "no irq\n"); + return -ENXIO; + } + + clk = devm_clk_get(dev, "spi"); + if (IS_ERR(clk)) { + dev_err(dev, "no clock for device\n"); + return PTR_ERR(clk); + } + + master = spi_alloc_master(dev, sizeof(*bs)); + if (!master) { + dev_err(dev, "out of memory\n"); + return -ENOMEM; + } + + bs = spi_master_get_devdata(master); + init_completion(&bs->done); + + platform_set_drvdata(pdev, master); + bs->pdev = pdev; + + r = platform_get_resource(pdev, IORESOURCE_MEM, 0); + bs->regs = devm_ioremap_resource(&pdev->dev, r); + if (IS_ERR(bs->regs)) { + ret = PTR_ERR(bs->regs); + goto out_err; + } + + bs->irq = irq; + bs->clk = clk; + bs->fifo_size = pdata->fifo_size; + + ret = devm_request_irq(&pdev->dev, irq, bcm63xx_spi_interrupt, 0, + pdev->name, master); + if (ret) { + dev_err(dev, "unable to request irq\n"); + goto out_err; + } + + master->bus_num = pdata->bus_num; + master->num_chipselect = pdata->num_chipselect; + master->transfer_one_message = bcm63xx_spi_transfer_one; + master->mode_bits = MODEBITS; + master->bits_per_word_mask = SPI_BPW_MASK(8); + master->auto_runtime_pm = true; + bs->msg_type_shift = pdata->msg_type_shift; + bs->msg_ctl_width = pdata->msg_ctl_width; + bs->tx_io = (u8 *)(bs->regs + bcm63xx_spireg(SPI_MSG_DATA)); + bs->rx_io = (const u8 *)(bs->regs + bcm63xx_spireg(SPI_RX_DATA)); + + switch (bs->msg_ctl_width) { + case 8: + case 16: + break; + default: + dev_err(dev, "unsupported MSG_CTL width: %d\n", + bs->msg_ctl_width); + goto out_err; + } + + /* Initialize hardware */ + ret = clk_prepare_enable(bs->clk); + if (ret) + goto out_err; + + bcm_spi_writeb(bs, SPI_INTR_CLEAR_ALL, SPI_INT_STATUS); + + /* register and we are done */ + ret = devm_spi_register_master(dev, master); + if (ret) { + dev_err(dev, "spi register failed\n"); + goto out_clk_disable; + } + + dev_info(dev, "at 0x%08x (irq %d, FIFOs size %d)\n", + r->start, irq, bs->fifo_size); + + return 0; + +out_clk_disable: + clk_disable_unprepare(clk); +out_err: + spi_master_put(master); + return ret; +} + +static int bcm63xx_spi_remove(struct platform_device *pdev) +{ + struct spi_master *master = platform_get_drvdata(pdev); + struct bcm63xx_spi *bs = spi_master_get_devdata(master); + + /* reset spi block */ + bcm_spi_writeb(bs, 0, SPI_INT_MASK); + + /* HW shutdown */ + clk_disable_unprepare(bs->clk); + + return 0; +} + +#ifdef CONFIG_PM_SLEEP +static int bcm63xx_spi_suspend(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct bcm63xx_spi *bs = spi_master_get_devdata(master); + + spi_master_suspend(master); + + clk_disable_unprepare(bs->clk); + + return 0; +} + +static int bcm63xx_spi_resume(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct bcm63xx_spi *bs = spi_master_get_devdata(master); + int ret; + + ret = clk_prepare_enable(bs->clk); + if (ret) + return ret; + + spi_master_resume(master); + + return 0; +} +#endif + +static const struct dev_pm_ops bcm63xx_spi_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(bcm63xx_spi_suspend, bcm63xx_spi_resume) +}; + +static struct platform_driver bcm63xx_spi_driver = { + .driver = { + .name = "bcm63xx-spi", + .pm = &bcm63xx_spi_pm_ops, + }, + .probe = bcm63xx_spi_probe, + .remove = bcm63xx_spi_remove, +}; + +module_platform_driver(bcm63xx_spi_driver); + +MODULE_ALIAS("platform:bcm63xx_spi"); +MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>"); +MODULE_AUTHOR("Tanguy Bouzeloc <tanguy.bouzeloc@efixo.com>"); +MODULE_DESCRIPTION("Broadcom BCM63xx SPI Controller driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/spi/spi-bfin-sport.c b/drivers/spi/spi-bfin-sport.c new file mode 100644 index 000000000..a78693189 --- /dev/null +++ b/drivers/spi/spi-bfin-sport.c @@ -0,0 +1,929 @@ +/* + * SPI bus via the Blackfin SPORT peripheral + * + * Enter bugs at http://blackfin.uclinux.org/ + * + * Copyright 2009-2011 Analog Devices Inc. + * + * Licensed under the GPL-2 or later. + */ + +#include <linux/module.h> +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/gpio.h> +#include <linux/io.h> +#include <linux/ioport.h> +#include <linux/irq.h> +#include <linux/errno.h> +#include <linux/interrupt.h> +#include <linux/platform_device.h> +#include <linux/spi/spi.h> +#include <linux/workqueue.h> + +#include <asm/portmux.h> +#include <asm/bfin5xx_spi.h> +#include <asm/blackfin.h> +#include <asm/bfin_sport.h> +#include <asm/cacheflush.h> + +#define DRV_NAME "bfin-sport-spi" +#define DRV_DESC "SPI bus via the Blackfin SPORT" + +MODULE_AUTHOR("Cliff Cai"); +MODULE_DESCRIPTION(DRV_DESC); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:bfin-sport-spi"); + +enum bfin_sport_spi_state { + START_STATE, + RUNNING_STATE, + DONE_STATE, + ERROR_STATE, +}; + +struct bfin_sport_spi_master_data; + +struct bfin_sport_transfer_ops { + void (*write) (struct bfin_sport_spi_master_data *); + void (*read) (struct bfin_sport_spi_master_data *); + void (*duplex) (struct bfin_sport_spi_master_data *); +}; + +struct bfin_sport_spi_master_data { + /* Driver model hookup */ + struct device *dev; + + /* SPI framework hookup */ + struct spi_master *master; + + /* Regs base of SPI controller */ + struct sport_register __iomem *regs; + int err_irq; + + /* Pin request list */ + u16 *pin_req; + + /* Driver message queue */ + struct workqueue_struct *workqueue; + struct work_struct pump_messages; + spinlock_t lock; + struct list_head queue; + int busy; + bool run; + + /* Message Transfer pump */ + struct tasklet_struct pump_transfers; + + /* Current message transfer state info */ + enum bfin_sport_spi_state state; + struct spi_message *cur_msg; + struct spi_transfer *cur_transfer; + struct bfin_sport_spi_slave_data *cur_chip; + union { + void *tx; + u8 *tx8; + u16 *tx16; + }; + void *tx_end; + union { + void *rx; + u8 *rx8; + u16 *rx16; + }; + void *rx_end; + + int cs_change; + struct bfin_sport_transfer_ops *ops; +}; + +struct bfin_sport_spi_slave_data { + u16 ctl_reg; + u16 baud; + u16 cs_chg_udelay; /* Some devices require > 255usec delay */ + u32 cs_gpio; + u16 idle_tx_val; + struct bfin_sport_transfer_ops *ops; +}; + +static void +bfin_sport_spi_enable(struct bfin_sport_spi_master_data *drv_data) +{ + bfin_write_or(&drv_data->regs->tcr1, TSPEN); + bfin_write_or(&drv_data->regs->rcr1, TSPEN); + SSYNC(); +} + +static void +bfin_sport_spi_disable(struct bfin_sport_spi_master_data *drv_data) +{ + bfin_write_and(&drv_data->regs->tcr1, ~TSPEN); + bfin_write_and(&drv_data->regs->rcr1, ~TSPEN); + SSYNC(); +} + +/* Caculate the SPI_BAUD register value based on input HZ */ +static u16 +bfin_sport_hz_to_spi_baud(u32 speed_hz) +{ + u_long clk, sclk = get_sclk(); + int div = (sclk / (2 * speed_hz)) - 1; + + if (div < 0) + div = 0; + + clk = sclk / (2 * (div + 1)); + + if (clk > speed_hz) + div++; + + return div; +} + +/* Chip select operation functions for cs_change flag */ +static void +bfin_sport_spi_cs_active(struct bfin_sport_spi_slave_data *chip) +{ + gpio_direction_output(chip->cs_gpio, 0); +} + +static void +bfin_sport_spi_cs_deactive(struct bfin_sport_spi_slave_data *chip) +{ + gpio_direction_output(chip->cs_gpio, 1); + /* Move delay here for consistency */ + if (chip->cs_chg_udelay) + udelay(chip->cs_chg_udelay); +} + +static void +bfin_sport_spi_stat_poll_complete(struct bfin_sport_spi_master_data *drv_data) +{ + unsigned long timeout = jiffies + HZ; + while (!(bfin_read(&drv_data->regs->stat) & RXNE)) { + if (!time_before(jiffies, timeout)) + break; + } +} + +static void +bfin_sport_spi_u8_writer(struct bfin_sport_spi_master_data *drv_data) +{ + u16 dummy; + + while (drv_data->tx < drv_data->tx_end) { + bfin_write(&drv_data->regs->tx16, *drv_data->tx8++); + bfin_sport_spi_stat_poll_complete(drv_data); + dummy = bfin_read(&drv_data->regs->rx16); + } +} + +static void +bfin_sport_spi_u8_reader(struct bfin_sport_spi_master_data *drv_data) +{ + u16 tx_val = drv_data->cur_chip->idle_tx_val; + + while (drv_data->rx < drv_data->rx_end) { + bfin_write(&drv_data->regs->tx16, tx_val); + bfin_sport_spi_stat_poll_complete(drv_data); + *drv_data->rx8++ = bfin_read(&drv_data->regs->rx16); + } +} + +static void +bfin_sport_spi_u8_duplex(struct bfin_sport_spi_master_data *drv_data) +{ + while (drv_data->rx < drv_data->rx_end) { + bfin_write(&drv_data->regs->tx16, *drv_data->tx8++); + bfin_sport_spi_stat_poll_complete(drv_data); + *drv_data->rx8++ = bfin_read(&drv_data->regs->rx16); + } +} + +static struct bfin_sport_transfer_ops bfin_sport_transfer_ops_u8 = { + .write = bfin_sport_spi_u8_writer, + .read = bfin_sport_spi_u8_reader, + .duplex = bfin_sport_spi_u8_duplex, +}; + +static void +bfin_sport_spi_u16_writer(struct bfin_sport_spi_master_data *drv_data) +{ + u16 dummy; + + while (drv_data->tx < drv_data->tx_end) { + bfin_write(&drv_data->regs->tx16, *drv_data->tx16++); + bfin_sport_spi_stat_poll_complete(drv_data); + dummy = bfin_read(&drv_data->regs->rx16); + } +} + +static void +bfin_sport_spi_u16_reader(struct bfin_sport_spi_master_data *drv_data) +{ + u16 tx_val = drv_data->cur_chip->idle_tx_val; + + while (drv_data->rx < drv_data->rx_end) { + bfin_write(&drv_data->regs->tx16, tx_val); + bfin_sport_spi_stat_poll_complete(drv_data); + *drv_data->rx16++ = bfin_read(&drv_data->regs->rx16); + } +} + +static void +bfin_sport_spi_u16_duplex(struct bfin_sport_spi_master_data *drv_data) +{ + while (drv_data->rx < drv_data->rx_end) { + bfin_write(&drv_data->regs->tx16, *drv_data->tx16++); + bfin_sport_spi_stat_poll_complete(drv_data); + *drv_data->rx16++ = bfin_read(&drv_data->regs->rx16); + } +} + +static struct bfin_sport_transfer_ops bfin_sport_transfer_ops_u16 = { + .write = bfin_sport_spi_u16_writer, + .read = bfin_sport_spi_u16_reader, + .duplex = bfin_sport_spi_u16_duplex, +}; + +/* stop controller and re-config current chip */ +static void +bfin_sport_spi_restore_state(struct bfin_sport_spi_master_data *drv_data) +{ + struct bfin_sport_spi_slave_data *chip = drv_data->cur_chip; + + bfin_sport_spi_disable(drv_data); + dev_dbg(drv_data->dev, "restoring spi ctl state\n"); + + bfin_write(&drv_data->regs->tcr1, chip->ctl_reg); + bfin_write(&drv_data->regs->tclkdiv, chip->baud); + SSYNC(); + + bfin_write(&drv_data->regs->rcr1, chip->ctl_reg & ~(ITCLK | ITFS)); + SSYNC(); + + bfin_sport_spi_cs_active(chip); +} + +/* test if there is more transfer to be done */ +static enum bfin_sport_spi_state +bfin_sport_spi_next_transfer(struct bfin_sport_spi_master_data *drv_data) +{ + struct spi_message *msg = drv_data->cur_msg; + struct spi_transfer *trans = drv_data->cur_transfer; + + /* Move to next transfer */ + if (trans->transfer_list.next != &msg->transfers) { + drv_data->cur_transfer = + list_entry(trans->transfer_list.next, + struct spi_transfer, transfer_list); + return RUNNING_STATE; + } + + return DONE_STATE; +} + +/* + * caller already set message->status; + * dma and pio irqs are blocked give finished message back + */ +static void +bfin_sport_spi_giveback(struct bfin_sport_spi_master_data *drv_data) +{ + struct bfin_sport_spi_slave_data *chip = drv_data->cur_chip; + unsigned long flags; + struct spi_message *msg; + + spin_lock_irqsave(&drv_data->lock, flags); + msg = drv_data->cur_msg; + drv_data->state = START_STATE; + drv_data->cur_msg = NULL; + drv_data->cur_transfer = NULL; + drv_data->cur_chip = NULL; + queue_work(drv_data->workqueue, &drv_data->pump_messages); + spin_unlock_irqrestore(&drv_data->lock, flags); + + if (!drv_data->cs_change) + bfin_sport_spi_cs_deactive(chip); + + if (msg->complete) + msg->complete(msg->context); +} + +static irqreturn_t +sport_err_handler(int irq, void *dev_id) +{ + struct bfin_sport_spi_master_data *drv_data = dev_id; + u16 status; + + dev_dbg(drv_data->dev, "%s enter\n", __func__); + status = bfin_read(&drv_data->regs->stat) & (TOVF | TUVF | ROVF | RUVF); + + if (status) { + bfin_write(&drv_data->regs->stat, status); + SSYNC(); + + bfin_sport_spi_disable(drv_data); + dev_err(drv_data->dev, "status error:%s%s%s%s\n", + status & TOVF ? " TOVF" : "", + status & TUVF ? " TUVF" : "", + status & ROVF ? " ROVF" : "", + status & RUVF ? " RUVF" : ""); + } + + return IRQ_HANDLED; +} + +static void +bfin_sport_spi_pump_transfers(unsigned long data) +{ + struct bfin_sport_spi_master_data *drv_data = (void *)data; + struct spi_message *message = NULL; + struct spi_transfer *transfer = NULL; + struct spi_transfer *previous = NULL; + struct bfin_sport_spi_slave_data *chip = NULL; + unsigned int bits_per_word; + u32 tranf_success = 1; + u32 transfer_speed; + u8 full_duplex = 0; + + /* Get current state information */ + message = drv_data->cur_msg; + transfer = drv_data->cur_transfer; + chip = drv_data->cur_chip; + + if (transfer->speed_hz) + transfer_speed = bfin_sport_hz_to_spi_baud(transfer->speed_hz); + else + transfer_speed = chip->baud; + bfin_write(&drv_data->regs->tclkdiv, transfer_speed); + SSYNC(); + + /* + * if msg is error or done, report it back using complete() callback + */ + + /* Handle for abort */ + if (drv_data->state == ERROR_STATE) { + dev_dbg(drv_data->dev, "transfer: we've hit an error\n"); + message->status = -EIO; + bfin_sport_spi_giveback(drv_data); + return; + } + + /* Handle end of message */ + if (drv_data->state == DONE_STATE) { + dev_dbg(drv_data->dev, "transfer: all done!\n"); + message->status = 0; + bfin_sport_spi_giveback(drv_data); + return; + } + + /* Delay if requested at end of transfer */ + if (drv_data->state == RUNNING_STATE) { + dev_dbg(drv_data->dev, "transfer: still running ...\n"); + previous = list_entry(transfer->transfer_list.prev, + struct spi_transfer, transfer_list); + if (previous->delay_usecs) + udelay(previous->delay_usecs); + } + + if (transfer->len == 0) { + /* Move to next transfer of this msg */ + drv_data->state = bfin_sport_spi_next_transfer(drv_data); + /* Schedule next transfer tasklet */ + tasklet_schedule(&drv_data->pump_transfers); + } + + if (transfer->tx_buf != NULL) { + drv_data->tx = (void *)transfer->tx_buf; + drv_data->tx_end = drv_data->tx + transfer->len; + dev_dbg(drv_data->dev, "tx_buf is %p, tx_end is %p\n", + transfer->tx_buf, drv_data->tx_end); + } else + drv_data->tx = NULL; + + if (transfer->rx_buf != NULL) { + full_duplex = transfer->tx_buf != NULL; + drv_data->rx = transfer->rx_buf; + drv_data->rx_end = drv_data->rx + transfer->len; + dev_dbg(drv_data->dev, "rx_buf is %p, rx_end is %p\n", + transfer->rx_buf, drv_data->rx_end); + } else + drv_data->rx = NULL; + + drv_data->cs_change = transfer->cs_change; + + /* Bits per word setup */ + bits_per_word = transfer->bits_per_word; + if (bits_per_word == 16) + drv_data->ops = &bfin_sport_transfer_ops_u16; + else + drv_data->ops = &bfin_sport_transfer_ops_u8; + bfin_write(&drv_data->regs->tcr2, bits_per_word - 1); + bfin_write(&drv_data->regs->tfsdiv, bits_per_word - 1); + bfin_write(&drv_data->regs->rcr2, bits_per_word - 1); + + drv_data->state = RUNNING_STATE; + + if (drv_data->cs_change) + bfin_sport_spi_cs_active(chip); + + dev_dbg(drv_data->dev, + "now pumping a transfer: width is %d, len is %d\n", + bits_per_word, transfer->len); + + /* PIO mode write then read */ + dev_dbg(drv_data->dev, "doing IO transfer\n"); + + bfin_sport_spi_enable(drv_data); + if (full_duplex) { + /* full duplex mode */ + BUG_ON((drv_data->tx_end - drv_data->tx) != + (drv_data->rx_end - drv_data->rx)); + drv_data->ops->duplex(drv_data); + + if (drv_data->tx != drv_data->tx_end) + tranf_success = 0; + } else if (drv_data->tx != NULL) { + /* write only half duplex */ + + drv_data->ops->write(drv_data); + + if (drv_data->tx != drv_data->tx_end) + tranf_success = 0; + } else if (drv_data->rx != NULL) { + /* read only half duplex */ + + drv_data->ops->read(drv_data); + if (drv_data->rx != drv_data->rx_end) + tranf_success = 0; + } + bfin_sport_spi_disable(drv_data); + + if (!tranf_success) { + dev_dbg(drv_data->dev, "IO write error!\n"); + drv_data->state = ERROR_STATE; + } else { + /* Update total byte transferred */ + message->actual_length += transfer->len; + /* Move to next transfer of this msg */ + drv_data->state = bfin_sport_spi_next_transfer(drv_data); + if (drv_data->cs_change) + bfin_sport_spi_cs_deactive(chip); + } + + /* Schedule next transfer tasklet */ + tasklet_schedule(&drv_data->pump_transfers); +} + +/* pop a msg from queue and kick off real transfer */ +static void +bfin_sport_spi_pump_messages(struct work_struct *work) +{ + struct bfin_sport_spi_master_data *drv_data; + unsigned long flags; + struct spi_message *next_msg; + + drv_data = container_of(work, struct bfin_sport_spi_master_data, pump_messages); + + /* Lock queue and check for queue work */ + spin_lock_irqsave(&drv_data->lock, flags); + if (list_empty(&drv_data->queue) || !drv_data->run) { + /* pumper kicked off but no work to do */ + drv_data->busy = 0; + spin_unlock_irqrestore(&drv_data->lock, flags); + return; + } + + /* Make sure we are not already running a message */ + if (drv_data->cur_msg) { + spin_unlock_irqrestore(&drv_data->lock, flags); + return; + } + + /* Extract head of queue */ + next_msg = list_entry(drv_data->queue.next, + struct spi_message, queue); + + drv_data->cur_msg = next_msg; + + /* Setup the SSP using the per chip configuration */ + drv_data->cur_chip = spi_get_ctldata(drv_data->cur_msg->spi); + + list_del_init(&drv_data->cur_msg->queue); + + /* Initialize message state */ + drv_data->cur_msg->state = START_STATE; + drv_data->cur_transfer = list_entry(drv_data->cur_msg->transfers.next, + struct spi_transfer, transfer_list); + bfin_sport_spi_restore_state(drv_data); + dev_dbg(drv_data->dev, "got a message to pump, " + "state is set to: baud %d, cs_gpio %i, ctl 0x%x\n", + drv_data->cur_chip->baud, drv_data->cur_chip->cs_gpio, + drv_data->cur_chip->ctl_reg); + + dev_dbg(drv_data->dev, + "the first transfer len is %d\n", + drv_data->cur_transfer->len); + + /* Mark as busy and launch transfers */ + tasklet_schedule(&drv_data->pump_transfers); + + drv_data->busy = 1; + spin_unlock_irqrestore(&drv_data->lock, flags); +} + +/* + * got a msg to transfer, queue it in drv_data->queue. + * And kick off message pumper + */ +static int +bfin_sport_spi_transfer(struct spi_device *spi, struct spi_message *msg) +{ + struct bfin_sport_spi_master_data *drv_data = spi_master_get_devdata(spi->master); + unsigned long flags; + + spin_lock_irqsave(&drv_data->lock, flags); + + if (!drv_data->run) { + spin_unlock_irqrestore(&drv_data->lock, flags); + return -ESHUTDOWN; + } + + msg->actual_length = 0; + msg->status = -EINPROGRESS; + msg->state = START_STATE; + + dev_dbg(&spi->dev, "adding an msg in transfer()\n"); + list_add_tail(&msg->queue, &drv_data->queue); + + if (drv_data->run && !drv_data->busy) + queue_work(drv_data->workqueue, &drv_data->pump_messages); + + spin_unlock_irqrestore(&drv_data->lock, flags); + + return 0; +} + +/* Called every time common spi devices change state */ +static int +bfin_sport_spi_setup(struct spi_device *spi) +{ + struct bfin_sport_spi_slave_data *chip, *first = NULL; + int ret; + + /* Only alloc (or use chip_info) on first setup */ + chip = spi_get_ctldata(spi); + if (chip == NULL) { + struct bfin5xx_spi_chip *chip_info; + + chip = first = kzalloc(sizeof(*chip), GFP_KERNEL); + if (!chip) + return -ENOMEM; + + /* platform chip_info isn't required */ + chip_info = spi->controller_data; + if (chip_info) { + /* + * DITFS and TDTYPE are only thing we don't set, but + * they probably shouldn't be changed by people. + */ + if (chip_info->ctl_reg || chip_info->enable_dma) { + ret = -EINVAL; + dev_err(&spi->dev, "don't set ctl_reg/enable_dma fields\n"); + goto error; + } + chip->cs_chg_udelay = chip_info->cs_chg_udelay; + chip->idle_tx_val = chip_info->idle_tx_val; + } + } + + /* translate common spi framework into our register + * following configure contents are same for tx and rx. + */ + + if (spi->mode & SPI_CPHA) + chip->ctl_reg &= ~TCKFE; + else + chip->ctl_reg |= TCKFE; + + if (spi->mode & SPI_LSB_FIRST) + chip->ctl_reg |= TLSBIT; + else + chip->ctl_reg &= ~TLSBIT; + + /* Sport in master mode */ + chip->ctl_reg |= ITCLK | ITFS | TFSR | LATFS | LTFS; + + chip->baud = bfin_sport_hz_to_spi_baud(spi->max_speed_hz); + + chip->cs_gpio = spi->chip_select; + ret = gpio_request(chip->cs_gpio, spi->modalias); + if (ret) + goto error; + + dev_dbg(&spi->dev, "setup spi chip %s, width is %d\n", + spi->modalias, spi->bits_per_word); + dev_dbg(&spi->dev, "ctl_reg is 0x%x, GPIO is %i\n", + chip->ctl_reg, spi->chip_select); + + spi_set_ctldata(spi, chip); + + bfin_sport_spi_cs_deactive(chip); + + return ret; + + error: + kfree(first); + return ret; +} + +/* + * callback for spi framework. + * clean driver specific data + */ +static void +bfin_sport_spi_cleanup(struct spi_device *spi) +{ + struct bfin_sport_spi_slave_data *chip = spi_get_ctldata(spi); + + if (!chip) + return; + + gpio_free(chip->cs_gpio); + + kfree(chip); +} + +static int +bfin_sport_spi_init_queue(struct bfin_sport_spi_master_data *drv_data) +{ + INIT_LIST_HEAD(&drv_data->queue); + spin_lock_init(&drv_data->lock); + + drv_data->run = false; + drv_data->busy = 0; + + /* init transfer tasklet */ + tasklet_init(&drv_data->pump_transfers, + bfin_sport_spi_pump_transfers, (unsigned long)drv_data); + + /* init messages workqueue */ + INIT_WORK(&drv_data->pump_messages, bfin_sport_spi_pump_messages); + drv_data->workqueue = + create_singlethread_workqueue(dev_name(drv_data->master->dev.parent)); + if (drv_data->workqueue == NULL) + return -EBUSY; + + return 0; +} + +static int +bfin_sport_spi_start_queue(struct bfin_sport_spi_master_data *drv_data) +{ + unsigned long flags; + + spin_lock_irqsave(&drv_data->lock, flags); + + if (drv_data->run || drv_data->busy) { + spin_unlock_irqrestore(&drv_data->lock, flags); + return -EBUSY; + } + + drv_data->run = true; + drv_data->cur_msg = NULL; + drv_data->cur_transfer = NULL; + drv_data->cur_chip = NULL; + spin_unlock_irqrestore(&drv_data->lock, flags); + + queue_work(drv_data->workqueue, &drv_data->pump_messages); + + return 0; +} + +static inline int +bfin_sport_spi_stop_queue(struct bfin_sport_spi_master_data *drv_data) +{ + unsigned long flags; + unsigned limit = 500; + int status = 0; + + spin_lock_irqsave(&drv_data->lock, flags); + + /* + * This is a bit lame, but is optimized for the common execution path. + * A wait_queue on the drv_data->busy could be used, but then the common + * execution path (pump_messages) would be required to call wake_up or + * friends on every SPI message. Do this instead + */ + drv_data->run = false; + while (!list_empty(&drv_data->queue) && drv_data->busy && limit--) { + spin_unlock_irqrestore(&drv_data->lock, flags); + msleep(10); + spin_lock_irqsave(&drv_data->lock, flags); + } + + if (!list_empty(&drv_data->queue) || drv_data->busy) + status = -EBUSY; + + spin_unlock_irqrestore(&drv_data->lock, flags); + + return status; +} + +static inline int +bfin_sport_spi_destroy_queue(struct bfin_sport_spi_master_data *drv_data) +{ + int status; + + status = bfin_sport_spi_stop_queue(drv_data); + if (status) + return status; + + destroy_workqueue(drv_data->workqueue); + + return 0; +} + +static int bfin_sport_spi_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct bfin5xx_spi_master *platform_info; + struct spi_master *master; + struct resource *res, *ires; + struct bfin_sport_spi_master_data *drv_data; + int status; + + platform_info = dev_get_platdata(dev); + + /* Allocate master with space for drv_data */ + master = spi_alloc_master(dev, sizeof(*master) + 16); + if (!master) { + dev_err(dev, "cannot alloc spi_master\n"); + return -ENOMEM; + } + + drv_data = spi_master_get_devdata(master); + drv_data->master = master; + drv_data->dev = dev; + drv_data->pin_req = platform_info->pin_req; + + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST; + master->bits_per_word_mask = SPI_BPW_MASK(8) | SPI_BPW_MASK(16); + master->bus_num = pdev->id; + master->num_chipselect = platform_info->num_chipselect; + master->cleanup = bfin_sport_spi_cleanup; + master->setup = bfin_sport_spi_setup; + master->transfer = bfin_sport_spi_transfer; + + /* Find and map our resources */ + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (res == NULL) { + dev_err(dev, "cannot get IORESOURCE_MEM\n"); + status = -ENOENT; + goto out_error_get_res; + } + + drv_data->regs = ioremap(res->start, resource_size(res)); + if (drv_data->regs == NULL) { + dev_err(dev, "cannot map registers\n"); + status = -ENXIO; + goto out_error_ioremap; + } + + ires = platform_get_resource(pdev, IORESOURCE_IRQ, 0); + if (!ires) { + dev_err(dev, "cannot get IORESOURCE_IRQ\n"); + status = -ENODEV; + goto out_error_get_ires; + } + drv_data->err_irq = ires->start; + + /* Initial and start queue */ + status = bfin_sport_spi_init_queue(drv_data); + if (status) { + dev_err(dev, "problem initializing queue\n"); + goto out_error_queue_alloc; + } + + status = bfin_sport_spi_start_queue(drv_data); + if (status) { + dev_err(dev, "problem starting queue\n"); + goto out_error_queue_alloc; + } + + status = request_irq(drv_data->err_irq, sport_err_handler, + 0, "sport_spi_err", drv_data); + if (status) { + dev_err(dev, "unable to request sport err irq\n"); + goto out_error_irq; + } + + status = peripheral_request_list(drv_data->pin_req, DRV_NAME); + if (status) { + dev_err(dev, "requesting peripherals failed\n"); + goto out_error_peripheral; + } + + /* Register with the SPI framework */ + platform_set_drvdata(pdev, drv_data); + status = spi_register_master(master); + if (status) { + dev_err(dev, "problem registering spi master\n"); + goto out_error_master; + } + + dev_info(dev, "%s, regs_base@%p\n", DRV_DESC, drv_data->regs); + return 0; + + out_error_master: + peripheral_free_list(drv_data->pin_req); + out_error_peripheral: + free_irq(drv_data->err_irq, drv_data); + out_error_irq: + out_error_queue_alloc: + bfin_sport_spi_destroy_queue(drv_data); + out_error_get_ires: + iounmap(drv_data->regs); + out_error_ioremap: + out_error_get_res: + spi_master_put(master); + + return status; +} + +/* stop hardware and remove the driver */ +static int bfin_sport_spi_remove(struct platform_device *pdev) +{ + struct bfin_sport_spi_master_data *drv_data = platform_get_drvdata(pdev); + int status = 0; + + if (!drv_data) + return 0; + + /* Remove the queue */ + status = bfin_sport_spi_destroy_queue(drv_data); + if (status) + return status; + + /* Disable the SSP at the peripheral and SOC level */ + bfin_sport_spi_disable(drv_data); + + /* Disconnect from the SPI framework */ + spi_unregister_master(drv_data->master); + + peripheral_free_list(drv_data->pin_req); + + return 0; +} + +#ifdef CONFIG_PM_SLEEP +static int bfin_sport_spi_suspend(struct device *dev) +{ + struct bfin_sport_spi_master_data *drv_data = dev_get_drvdata(dev); + int status; + + status = bfin_sport_spi_stop_queue(drv_data); + if (status) + return status; + + /* stop hardware */ + bfin_sport_spi_disable(drv_data); + + return status; +} + +static int bfin_sport_spi_resume(struct device *dev) +{ + struct bfin_sport_spi_master_data *drv_data = dev_get_drvdata(dev); + int status; + + /* Enable the SPI interface */ + bfin_sport_spi_enable(drv_data); + + /* Start the queue running */ + status = bfin_sport_spi_start_queue(drv_data); + if (status) + dev_err(drv_data->dev, "problem resuming queue\n"); + + return status; +} + +static SIMPLE_DEV_PM_OPS(bfin_sport_spi_pm_ops, bfin_sport_spi_suspend, + bfin_sport_spi_resume); + +#define BFIN_SPORT_SPI_PM_OPS (&bfin_sport_spi_pm_ops) +#else +#define BFIN_SPORT_SPI_PM_OPS NULL +#endif + +static struct platform_driver bfin_sport_spi_driver = { + .driver = { + .name = DRV_NAME, + .pm = BFIN_SPORT_SPI_PM_OPS, + }, + .probe = bfin_sport_spi_probe, + .remove = bfin_sport_spi_remove, +}; +module_platform_driver(bfin_sport_spi_driver); diff --git a/drivers/spi/spi-bfin5xx.c b/drivers/spi/spi-bfin5xx.c new file mode 100644 index 000000000..a3d65b4f4 --- /dev/null +++ b/drivers/spi/spi-bfin5xx.c @@ -0,0 +1,1473 @@ +/* + * Blackfin On-Chip SPI Driver + * + * Copyright 2004-2010 Analog Devices Inc. + * + * Enter bugs at http://blackfin.uclinux.org/ + * + * Licensed under the GPL-2 or later. + */ + +#include <linux/init.h> +#include <linux/module.h> +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/gpio.h> +#include <linux/slab.h> +#include <linux/io.h> +#include <linux/ioport.h> +#include <linux/irq.h> +#include <linux/errno.h> +#include <linux/interrupt.h> +#include <linux/platform_device.h> +#include <linux/dma-mapping.h> +#include <linux/spi/spi.h> +#include <linux/workqueue.h> + +#include <asm/dma.h> +#include <asm/portmux.h> +#include <asm/bfin5xx_spi.h> +#include <asm/cacheflush.h> + +#define DRV_NAME "bfin-spi" +#define DRV_AUTHOR "Bryan Wu, Luke Yang" +#define DRV_DESC "Blackfin on-chip SPI Controller Driver" +#define DRV_VERSION "1.0" + +MODULE_AUTHOR(DRV_AUTHOR); +MODULE_DESCRIPTION(DRV_DESC); +MODULE_LICENSE("GPL"); + +#define START_STATE ((void *)0) +#define RUNNING_STATE ((void *)1) +#define DONE_STATE ((void *)2) +#define ERROR_STATE ((void *)-1) + +struct bfin_spi_master_data; + +struct bfin_spi_transfer_ops { + void (*write) (struct bfin_spi_master_data *); + void (*read) (struct bfin_spi_master_data *); + void (*duplex) (struct bfin_spi_master_data *); +}; + +struct bfin_spi_master_data { + /* Driver model hookup */ + struct platform_device *pdev; + + /* SPI framework hookup */ + struct spi_master *master; + + /* Regs base of SPI controller */ + struct bfin_spi_regs __iomem *regs; + + /* Pin request list */ + u16 *pin_req; + + /* BFIN hookup */ + struct bfin5xx_spi_master *master_info; + + /* Driver message queue */ + struct workqueue_struct *workqueue; + struct work_struct pump_messages; + spinlock_t lock; + struct list_head queue; + int busy; + bool running; + + /* Message Transfer pump */ + struct tasklet_struct pump_transfers; + + /* Current message transfer state info */ + struct spi_message *cur_msg; + struct spi_transfer *cur_transfer; + struct bfin_spi_slave_data *cur_chip; + size_t len_in_bytes; + size_t len; + void *tx; + void *tx_end; + void *rx; + void *rx_end; + + /* DMA stuffs */ + int dma_channel; + int dma_mapped; + int dma_requested; + dma_addr_t rx_dma; + dma_addr_t tx_dma; + + int irq_requested; + int spi_irq; + + size_t rx_map_len; + size_t tx_map_len; + u8 n_bytes; + u16 ctrl_reg; + u16 flag_reg; + + int cs_change; + const struct bfin_spi_transfer_ops *ops; +}; + +struct bfin_spi_slave_data { + u16 ctl_reg; + u16 baud; + u16 flag; + + u8 chip_select_num; + u8 enable_dma; + u16 cs_chg_udelay; /* Some devices require > 255usec delay */ + u32 cs_gpio; + u16 idle_tx_val; + u8 pio_interrupt; /* use spi data irq */ + const struct bfin_spi_transfer_ops *ops; +}; + +static void bfin_spi_enable(struct bfin_spi_master_data *drv_data) +{ + bfin_write_or(&drv_data->regs->ctl, BIT_CTL_ENABLE); +} + +static void bfin_spi_disable(struct bfin_spi_master_data *drv_data) +{ + bfin_write_and(&drv_data->regs->ctl, ~BIT_CTL_ENABLE); +} + +/* Caculate the SPI_BAUD register value based on input HZ */ +static u16 hz_to_spi_baud(u32 speed_hz) +{ + u_long sclk = get_sclk(); + u16 spi_baud = (sclk / (2 * speed_hz)); + + if ((sclk % (2 * speed_hz)) > 0) + spi_baud++; + + if (spi_baud < MIN_SPI_BAUD_VAL) + spi_baud = MIN_SPI_BAUD_VAL; + + return spi_baud; +} + +static int bfin_spi_flush(struct bfin_spi_master_data *drv_data) +{ + unsigned long limit = loops_per_jiffy << 1; + + /* wait for stop and clear stat */ + while (!(bfin_read(&drv_data->regs->stat) & BIT_STAT_SPIF) && --limit) + cpu_relax(); + + bfin_write(&drv_data->regs->stat, BIT_STAT_CLR); + + return limit; +} + +/* Chip select operation functions for cs_change flag */ +static void bfin_spi_cs_active(struct bfin_spi_master_data *drv_data, struct bfin_spi_slave_data *chip) +{ + if (likely(chip->chip_select_num < MAX_CTRL_CS)) + bfin_write_and(&drv_data->regs->flg, ~chip->flag); + else + gpio_set_value(chip->cs_gpio, 0); +} + +static void bfin_spi_cs_deactive(struct bfin_spi_master_data *drv_data, + struct bfin_spi_slave_data *chip) +{ + if (likely(chip->chip_select_num < MAX_CTRL_CS)) + bfin_write_or(&drv_data->regs->flg, chip->flag); + else + gpio_set_value(chip->cs_gpio, 1); + + /* Move delay here for consistency */ + if (chip->cs_chg_udelay) + udelay(chip->cs_chg_udelay); +} + +/* enable or disable the pin muxed by GPIO and SPI CS to work as SPI CS */ +static inline void bfin_spi_cs_enable(struct bfin_spi_master_data *drv_data, + struct bfin_spi_slave_data *chip) +{ + if (chip->chip_select_num < MAX_CTRL_CS) + bfin_write_or(&drv_data->regs->flg, chip->flag >> 8); +} + +static inline void bfin_spi_cs_disable(struct bfin_spi_master_data *drv_data, + struct bfin_spi_slave_data *chip) +{ + if (chip->chip_select_num < MAX_CTRL_CS) + bfin_write_and(&drv_data->regs->flg, ~(chip->flag >> 8)); +} + +/* stop controller and re-config current chip*/ +static void bfin_spi_restore_state(struct bfin_spi_master_data *drv_data) +{ + struct bfin_spi_slave_data *chip = drv_data->cur_chip; + + /* Clear status and disable clock */ + bfin_write(&drv_data->regs->stat, BIT_STAT_CLR); + bfin_spi_disable(drv_data); + dev_dbg(&drv_data->pdev->dev, "restoring spi ctl state\n"); + + SSYNC(); + + /* Load the registers */ + bfin_write(&drv_data->regs->ctl, chip->ctl_reg); + bfin_write(&drv_data->regs->baud, chip->baud); + + bfin_spi_enable(drv_data); + bfin_spi_cs_active(drv_data, chip); +} + +/* used to kick off transfer in rx mode and read unwanted RX data */ +static inline void bfin_spi_dummy_read(struct bfin_spi_master_data *drv_data) +{ + (void) bfin_read(&drv_data->regs->rdbr); +} + +static void bfin_spi_u8_writer(struct bfin_spi_master_data *drv_data) +{ + /* clear RXS (we check for RXS inside the loop) */ + bfin_spi_dummy_read(drv_data); + + while (drv_data->tx < drv_data->tx_end) { + bfin_write(&drv_data->regs->tdbr, (*(u8 *) (drv_data->tx++))); + /* wait until transfer finished. + checking SPIF or TXS may not guarantee transfer completion */ + while (!(bfin_read(&drv_data->regs->stat) & BIT_STAT_RXS)) + cpu_relax(); + /* discard RX data and clear RXS */ + bfin_spi_dummy_read(drv_data); + } +} + +static void bfin_spi_u8_reader(struct bfin_spi_master_data *drv_data) +{ + u16 tx_val = drv_data->cur_chip->idle_tx_val; + + /* discard old RX data and clear RXS */ + bfin_spi_dummy_read(drv_data); + + while (drv_data->rx < drv_data->rx_end) { + bfin_write(&drv_data->regs->tdbr, tx_val); + while (!(bfin_read(&drv_data->regs->stat) & BIT_STAT_RXS)) + cpu_relax(); + *(u8 *) (drv_data->rx++) = bfin_read(&drv_data->regs->rdbr); + } +} + +static void bfin_spi_u8_duplex(struct bfin_spi_master_data *drv_data) +{ + /* discard old RX data and clear RXS */ + bfin_spi_dummy_read(drv_data); + + while (drv_data->rx < drv_data->rx_end) { + bfin_write(&drv_data->regs->tdbr, (*(u8 *) (drv_data->tx++))); + while (!(bfin_read(&drv_data->regs->stat) & BIT_STAT_RXS)) + cpu_relax(); + *(u8 *) (drv_data->rx++) = bfin_read(&drv_data->regs->rdbr); + } +} + +static const struct bfin_spi_transfer_ops bfin_bfin_spi_transfer_ops_u8 = { + .write = bfin_spi_u8_writer, + .read = bfin_spi_u8_reader, + .duplex = bfin_spi_u8_duplex, +}; + +static void bfin_spi_u16_writer(struct bfin_spi_master_data *drv_data) +{ + /* clear RXS (we check for RXS inside the loop) */ + bfin_spi_dummy_read(drv_data); + + while (drv_data->tx < drv_data->tx_end) { + bfin_write(&drv_data->regs->tdbr, (*(u16 *) (drv_data->tx))); + drv_data->tx += 2; + /* wait until transfer finished. + checking SPIF or TXS may not guarantee transfer completion */ + while (!(bfin_read(&drv_data->regs->stat) & BIT_STAT_RXS)) + cpu_relax(); + /* discard RX data and clear RXS */ + bfin_spi_dummy_read(drv_data); + } +} + +static void bfin_spi_u16_reader(struct bfin_spi_master_data *drv_data) +{ + u16 tx_val = drv_data->cur_chip->idle_tx_val; + + /* discard old RX data and clear RXS */ + bfin_spi_dummy_read(drv_data); + + while (drv_data->rx < drv_data->rx_end) { + bfin_write(&drv_data->regs->tdbr, tx_val); + while (!(bfin_read(&drv_data->regs->stat) & BIT_STAT_RXS)) + cpu_relax(); + *(u16 *) (drv_data->rx) = bfin_read(&drv_data->regs->rdbr); + drv_data->rx += 2; + } +} + +static void bfin_spi_u16_duplex(struct bfin_spi_master_data *drv_data) +{ + /* discard old RX data and clear RXS */ + bfin_spi_dummy_read(drv_data); + + while (drv_data->rx < drv_data->rx_end) { + bfin_write(&drv_data->regs->tdbr, (*(u16 *) (drv_data->tx))); + drv_data->tx += 2; + while (!(bfin_read(&drv_data->regs->stat) & BIT_STAT_RXS)) + cpu_relax(); + *(u16 *) (drv_data->rx) = bfin_read(&drv_data->regs->rdbr); + drv_data->rx += 2; + } +} + +static const struct bfin_spi_transfer_ops bfin_bfin_spi_transfer_ops_u16 = { + .write = bfin_spi_u16_writer, + .read = bfin_spi_u16_reader, + .duplex = bfin_spi_u16_duplex, +}; + +/* test if there is more transfer to be done */ +static void *bfin_spi_next_transfer(struct bfin_spi_master_data *drv_data) +{ + struct spi_message *msg = drv_data->cur_msg; + struct spi_transfer *trans = drv_data->cur_transfer; + + /* Move to next transfer */ + if (trans->transfer_list.next != &msg->transfers) { + drv_data->cur_transfer = + list_entry(trans->transfer_list.next, + struct spi_transfer, transfer_list); + return RUNNING_STATE; + } else + return DONE_STATE; +} + +/* + * caller already set message->status; + * dma and pio irqs are blocked give finished message back + */ +static void bfin_spi_giveback(struct bfin_spi_master_data *drv_data) +{ + struct bfin_spi_slave_data *chip = drv_data->cur_chip; + unsigned long flags; + struct spi_message *msg; + + spin_lock_irqsave(&drv_data->lock, flags); + msg = drv_data->cur_msg; + drv_data->cur_msg = NULL; + drv_data->cur_transfer = NULL; + drv_data->cur_chip = NULL; + queue_work(drv_data->workqueue, &drv_data->pump_messages); + spin_unlock_irqrestore(&drv_data->lock, flags); + + msg->state = NULL; + + if (!drv_data->cs_change) + bfin_spi_cs_deactive(drv_data, chip); + + /* Not stop spi in autobuffer mode */ + if (drv_data->tx_dma != 0xFFFF) + bfin_spi_disable(drv_data); + + if (msg->complete) + msg->complete(msg->context); +} + +/* spi data irq handler */ +static irqreturn_t bfin_spi_pio_irq_handler(int irq, void *dev_id) +{ + struct bfin_spi_master_data *drv_data = dev_id; + struct bfin_spi_slave_data *chip = drv_data->cur_chip; + struct spi_message *msg = drv_data->cur_msg; + int n_bytes = drv_data->n_bytes; + int loop = 0; + + /* wait until transfer finished. */ + while (!(bfin_read(&drv_data->regs->stat) & BIT_STAT_RXS)) + cpu_relax(); + + if ((drv_data->tx && drv_data->tx >= drv_data->tx_end) || + (drv_data->rx && drv_data->rx >= (drv_data->rx_end - n_bytes))) { + /* last read */ + if (drv_data->rx) { + dev_dbg(&drv_data->pdev->dev, "last read\n"); + if (!(n_bytes % 2)) { + u16 *buf = (u16 *)drv_data->rx; + for (loop = 0; loop < n_bytes / 2; loop++) + *buf++ = bfin_read(&drv_data->regs->rdbr); + } else { + u8 *buf = (u8 *)drv_data->rx; + for (loop = 0; loop < n_bytes; loop++) + *buf++ = bfin_read(&drv_data->regs->rdbr); + } + drv_data->rx += n_bytes; + } + + msg->actual_length += drv_data->len_in_bytes; + if (drv_data->cs_change) + bfin_spi_cs_deactive(drv_data, chip); + /* Move to next transfer */ + msg->state = bfin_spi_next_transfer(drv_data); + + disable_irq_nosync(drv_data->spi_irq); + + /* Schedule transfer tasklet */ + tasklet_schedule(&drv_data->pump_transfers); + return IRQ_HANDLED; + } + + if (drv_data->rx && drv_data->tx) { + /* duplex */ + dev_dbg(&drv_data->pdev->dev, "duplex: write_TDBR\n"); + if (!(n_bytes % 2)) { + u16 *buf = (u16 *)drv_data->rx; + u16 *buf2 = (u16 *)drv_data->tx; + for (loop = 0; loop < n_bytes / 2; loop++) { + *buf++ = bfin_read(&drv_data->regs->rdbr); + bfin_write(&drv_data->regs->tdbr, *buf2++); + } + } else { + u8 *buf = (u8 *)drv_data->rx; + u8 *buf2 = (u8 *)drv_data->tx; + for (loop = 0; loop < n_bytes; loop++) { + *buf++ = bfin_read(&drv_data->regs->rdbr); + bfin_write(&drv_data->regs->tdbr, *buf2++); + } + } + } else if (drv_data->rx) { + /* read */ + dev_dbg(&drv_data->pdev->dev, "read: write_TDBR\n"); + if (!(n_bytes % 2)) { + u16 *buf = (u16 *)drv_data->rx; + for (loop = 0; loop < n_bytes / 2; loop++) { + *buf++ = bfin_read(&drv_data->regs->rdbr); + bfin_write(&drv_data->regs->tdbr, chip->idle_tx_val); + } + } else { + u8 *buf = (u8 *)drv_data->rx; + for (loop = 0; loop < n_bytes; loop++) { + *buf++ = bfin_read(&drv_data->regs->rdbr); + bfin_write(&drv_data->regs->tdbr, chip->idle_tx_val); + } + } + } else if (drv_data->tx) { + /* write */ + dev_dbg(&drv_data->pdev->dev, "write: write_TDBR\n"); + if (!(n_bytes % 2)) { + u16 *buf = (u16 *)drv_data->tx; + for (loop = 0; loop < n_bytes / 2; loop++) { + bfin_read(&drv_data->regs->rdbr); + bfin_write(&drv_data->regs->tdbr, *buf++); + } + } else { + u8 *buf = (u8 *)drv_data->tx; + for (loop = 0; loop < n_bytes; loop++) { + bfin_read(&drv_data->regs->rdbr); + bfin_write(&drv_data->regs->tdbr, *buf++); + } + } + } + + if (drv_data->tx) + drv_data->tx += n_bytes; + if (drv_data->rx) + drv_data->rx += n_bytes; + + return IRQ_HANDLED; +} + +static irqreturn_t bfin_spi_dma_irq_handler(int irq, void *dev_id) +{ + struct bfin_spi_master_data *drv_data = dev_id; + struct bfin_spi_slave_data *chip = drv_data->cur_chip; + struct spi_message *msg = drv_data->cur_msg; + unsigned long timeout; + unsigned short dmastat = get_dma_curr_irqstat(drv_data->dma_channel); + u16 spistat = bfin_read(&drv_data->regs->stat); + + dev_dbg(&drv_data->pdev->dev, + "in dma_irq_handler dmastat:0x%x spistat:0x%x\n", + dmastat, spistat); + + if (drv_data->rx != NULL) { + u16 cr = bfin_read(&drv_data->regs->ctl); + /* discard old RX data and clear RXS */ + bfin_spi_dummy_read(drv_data); + bfin_write(&drv_data->regs->ctl, cr & ~BIT_CTL_ENABLE); /* Disable SPI */ + bfin_write(&drv_data->regs->ctl, cr & ~BIT_CTL_TIMOD); /* Restore State */ + bfin_write(&drv_data->regs->stat, BIT_STAT_CLR); /* Clear Status */ + } + + clear_dma_irqstat(drv_data->dma_channel); + + /* + * wait for the last transaction shifted out. HRM states: + * at this point there may still be data in the SPI DMA FIFO waiting + * to be transmitted ... software needs to poll TXS in the SPI_STAT + * register until it goes low for 2 successive reads + */ + if (drv_data->tx != NULL) { + while ((bfin_read(&drv_data->regs->stat) & BIT_STAT_TXS) || + (bfin_read(&drv_data->regs->stat) & BIT_STAT_TXS)) + cpu_relax(); + } + + dev_dbg(&drv_data->pdev->dev, + "in dma_irq_handler dmastat:0x%x spistat:0x%x\n", + dmastat, bfin_read(&drv_data->regs->stat)); + + timeout = jiffies + HZ; + while (!(bfin_read(&drv_data->regs->stat) & BIT_STAT_SPIF)) + if (!time_before(jiffies, timeout)) { + dev_warn(&drv_data->pdev->dev, "timeout waiting for SPIF\n"); + break; + } else + cpu_relax(); + + if ((dmastat & DMA_ERR) && (spistat & BIT_STAT_RBSY)) { + msg->state = ERROR_STATE; + dev_err(&drv_data->pdev->dev, "dma receive: fifo/buffer overflow\n"); + } else { + msg->actual_length += drv_data->len_in_bytes; + + if (drv_data->cs_change) + bfin_spi_cs_deactive(drv_data, chip); + + /* Move to next transfer */ + msg->state = bfin_spi_next_transfer(drv_data); + } + + /* Schedule transfer tasklet */ + tasklet_schedule(&drv_data->pump_transfers); + + /* free the irq handler before next transfer */ + dev_dbg(&drv_data->pdev->dev, + "disable dma channel irq%d\n", + drv_data->dma_channel); + dma_disable_irq_nosync(drv_data->dma_channel); + + return IRQ_HANDLED; +} + +static void bfin_spi_pump_transfers(unsigned long data) +{ + struct bfin_spi_master_data *drv_data = (struct bfin_spi_master_data *)data; + struct spi_message *message = NULL; + struct spi_transfer *transfer = NULL; + struct spi_transfer *previous = NULL; + struct bfin_spi_slave_data *chip = NULL; + unsigned int bits_per_word; + u16 cr, cr_width = 0, dma_width, dma_config; + u32 tranf_success = 1; + u8 full_duplex = 0; + + /* Get current state information */ + message = drv_data->cur_msg; + transfer = drv_data->cur_transfer; + chip = drv_data->cur_chip; + + /* + * if msg is error or done, report it back using complete() callback + */ + + /* Handle for abort */ + if (message->state == ERROR_STATE) { + dev_dbg(&drv_data->pdev->dev, "transfer: we've hit an error\n"); + message->status = -EIO; + bfin_spi_giveback(drv_data); + return; + } + + /* Handle end of message */ + if (message->state == DONE_STATE) { + dev_dbg(&drv_data->pdev->dev, "transfer: all done!\n"); + message->status = 0; + bfin_spi_flush(drv_data); + bfin_spi_giveback(drv_data); + return; + } + + /* Delay if requested at end of transfer */ + if (message->state == RUNNING_STATE) { + dev_dbg(&drv_data->pdev->dev, "transfer: still running ...\n"); + previous = list_entry(transfer->transfer_list.prev, + struct spi_transfer, transfer_list); + if (previous->delay_usecs) + udelay(previous->delay_usecs); + } + + /* Flush any existing transfers that may be sitting in the hardware */ + if (bfin_spi_flush(drv_data) == 0) { + dev_err(&drv_data->pdev->dev, "pump_transfers: flush failed\n"); + message->status = -EIO; + bfin_spi_giveback(drv_data); + return; + } + + if (transfer->len == 0) { + /* Move to next transfer of this msg */ + message->state = bfin_spi_next_transfer(drv_data); + /* Schedule next transfer tasklet */ + tasklet_schedule(&drv_data->pump_transfers); + return; + } + + if (transfer->tx_buf != NULL) { + drv_data->tx = (void *)transfer->tx_buf; + drv_data->tx_end = drv_data->tx + transfer->len; + dev_dbg(&drv_data->pdev->dev, "tx_buf is %p, tx_end is %p\n", + transfer->tx_buf, drv_data->tx_end); + } else { + drv_data->tx = NULL; + } + + if (transfer->rx_buf != NULL) { + full_duplex = transfer->tx_buf != NULL; + drv_data->rx = transfer->rx_buf; + drv_data->rx_end = drv_data->rx + transfer->len; + dev_dbg(&drv_data->pdev->dev, "rx_buf is %p, rx_end is %p\n", + transfer->rx_buf, drv_data->rx_end); + } else { + drv_data->rx = NULL; + } + + drv_data->rx_dma = transfer->rx_dma; + drv_data->tx_dma = transfer->tx_dma; + drv_data->len_in_bytes = transfer->len; + drv_data->cs_change = transfer->cs_change; + + /* Bits per word setup */ + bits_per_word = transfer->bits_per_word; + if (bits_per_word == 16) { + drv_data->n_bytes = bits_per_word/8; + drv_data->len = (transfer->len) >> 1; + cr_width = BIT_CTL_WORDSIZE; + drv_data->ops = &bfin_bfin_spi_transfer_ops_u16; + } else if (bits_per_word == 8) { + drv_data->n_bytes = bits_per_word/8; + drv_data->len = transfer->len; + drv_data->ops = &bfin_bfin_spi_transfer_ops_u8; + } + cr = bfin_read(&drv_data->regs->ctl) & ~(BIT_CTL_TIMOD | BIT_CTL_WORDSIZE); + cr |= cr_width; + bfin_write(&drv_data->regs->ctl, cr); + + dev_dbg(&drv_data->pdev->dev, + "transfer: drv_data->ops is %p, chip->ops is %p, u8_ops is %p\n", + drv_data->ops, chip->ops, &bfin_bfin_spi_transfer_ops_u8); + + message->state = RUNNING_STATE; + dma_config = 0; + + /* Speed setup (surely valid because already checked) */ + if (transfer->speed_hz) + bfin_write(&drv_data->regs->baud, hz_to_spi_baud(transfer->speed_hz)); + else + bfin_write(&drv_data->regs->baud, chip->baud); + + bfin_write(&drv_data->regs->stat, BIT_STAT_CLR); + bfin_spi_cs_active(drv_data, chip); + + dev_dbg(&drv_data->pdev->dev, + "now pumping a transfer: width is %d, len is %d\n", + cr_width, transfer->len); + + /* + * Try to map dma buffer and do a dma transfer. If successful use, + * different way to r/w according to the enable_dma settings and if + * we are not doing a full duplex transfer (since the hardware does + * not support full duplex DMA transfers). + */ + if (!full_duplex && drv_data->cur_chip->enable_dma + && drv_data->len > 6) { + + unsigned long dma_start_addr, flags; + + disable_dma(drv_data->dma_channel); + clear_dma_irqstat(drv_data->dma_channel); + + /* config dma channel */ + dev_dbg(&drv_data->pdev->dev, "doing dma transfer\n"); + set_dma_x_count(drv_data->dma_channel, drv_data->len); + if (cr_width == BIT_CTL_WORDSIZE) { + set_dma_x_modify(drv_data->dma_channel, 2); + dma_width = WDSIZE_16; + } else { + set_dma_x_modify(drv_data->dma_channel, 1); + dma_width = WDSIZE_8; + } + + /* poll for SPI completion before start */ + while (!(bfin_read(&drv_data->regs->stat) & BIT_STAT_SPIF)) + cpu_relax(); + + /* dirty hack for autobuffer DMA mode */ + if (drv_data->tx_dma == 0xFFFF) { + dev_dbg(&drv_data->pdev->dev, + "doing autobuffer DMA out.\n"); + + /* no irq in autobuffer mode */ + dma_config = + (DMAFLOW_AUTO | RESTART | dma_width | DI_EN); + set_dma_config(drv_data->dma_channel, dma_config); + set_dma_start_addr(drv_data->dma_channel, + (unsigned long)drv_data->tx); + enable_dma(drv_data->dma_channel); + + /* start SPI transfer */ + bfin_write(&drv_data->regs->ctl, cr | BIT_CTL_TIMOD_DMA_TX); + + /* just return here, there can only be one transfer + * in this mode + */ + message->status = 0; + bfin_spi_giveback(drv_data); + return; + } + + /* In dma mode, rx or tx must be NULL in one transfer */ + dma_config = (RESTART | dma_width | DI_EN); + if (drv_data->rx != NULL) { + /* set transfer mode, and enable SPI */ + dev_dbg(&drv_data->pdev->dev, "doing DMA in to %p (size %zx)\n", + drv_data->rx, drv_data->len_in_bytes); + + /* invalidate caches, if needed */ + if (bfin_addr_dcacheable((unsigned long) drv_data->rx)) + invalidate_dcache_range((unsigned long) drv_data->rx, + (unsigned long) (drv_data->rx + + drv_data->len_in_bytes)); + + dma_config |= WNR; + dma_start_addr = (unsigned long)drv_data->rx; + cr |= BIT_CTL_TIMOD_DMA_RX | BIT_CTL_SENDOPT; + + } else if (drv_data->tx != NULL) { + dev_dbg(&drv_data->pdev->dev, "doing DMA out.\n"); + + /* flush caches, if needed */ + if (bfin_addr_dcacheable((unsigned long) drv_data->tx)) + flush_dcache_range((unsigned long) drv_data->tx, + (unsigned long) (drv_data->tx + + drv_data->len_in_bytes)); + + dma_start_addr = (unsigned long)drv_data->tx; + cr |= BIT_CTL_TIMOD_DMA_TX; + + } else + BUG(); + + /* oh man, here there be monsters ... and i dont mean the + * fluffy cute ones from pixar, i mean the kind that'll eat + * your data, kick your dog, and love it all. do *not* try + * and change these lines unless you (1) heavily test DMA + * with SPI flashes on a loaded system (e.g. ping floods), + * (2) know just how broken the DMA engine interaction with + * the SPI peripheral is, and (3) have someone else to blame + * when you screw it all up anyways. + */ + set_dma_start_addr(drv_data->dma_channel, dma_start_addr); + set_dma_config(drv_data->dma_channel, dma_config); + local_irq_save(flags); + SSYNC(); + bfin_write(&drv_data->regs->ctl, cr); + enable_dma(drv_data->dma_channel); + dma_enable_irq(drv_data->dma_channel); + local_irq_restore(flags); + + return; + } + + /* + * We always use SPI_WRITE mode (transfer starts with TDBR write). + * SPI_READ mode (transfer starts with RDBR read) seems to have + * problems with setting up the output value in TDBR prior to the + * start of the transfer. + */ + bfin_write(&drv_data->regs->ctl, cr | BIT_CTL_TXMOD); + + if (chip->pio_interrupt) { + /* SPI irq should have been disabled by now */ + + /* discard old RX data and clear RXS */ + bfin_spi_dummy_read(drv_data); + + /* start transfer */ + if (drv_data->tx == NULL) + bfin_write(&drv_data->regs->tdbr, chip->idle_tx_val); + else { + int loop; + if (bits_per_word == 16) { + u16 *buf = (u16 *)drv_data->tx; + for (loop = 0; loop < bits_per_word / 16; + loop++) { + bfin_write(&drv_data->regs->tdbr, *buf++); + } + } else if (bits_per_word == 8) { + u8 *buf = (u8 *)drv_data->tx; + for (loop = 0; loop < bits_per_word / 8; loop++) + bfin_write(&drv_data->regs->tdbr, *buf++); + } + + drv_data->tx += drv_data->n_bytes; + } + + /* once TDBR is empty, interrupt is triggered */ + enable_irq(drv_data->spi_irq); + return; + } + + /* IO mode */ + dev_dbg(&drv_data->pdev->dev, "doing IO transfer\n"); + + if (full_duplex) { + /* full duplex mode */ + BUG_ON((drv_data->tx_end - drv_data->tx) != + (drv_data->rx_end - drv_data->rx)); + dev_dbg(&drv_data->pdev->dev, + "IO duplex: cr is 0x%x\n", cr); + + drv_data->ops->duplex(drv_data); + + if (drv_data->tx != drv_data->tx_end) + tranf_success = 0; + } else if (drv_data->tx != NULL) { + /* write only half duplex */ + dev_dbg(&drv_data->pdev->dev, + "IO write: cr is 0x%x\n", cr); + + drv_data->ops->write(drv_data); + + if (drv_data->tx != drv_data->tx_end) + tranf_success = 0; + } else if (drv_data->rx != NULL) { + /* read only half duplex */ + dev_dbg(&drv_data->pdev->dev, + "IO read: cr is 0x%x\n", cr); + + drv_data->ops->read(drv_data); + if (drv_data->rx != drv_data->rx_end) + tranf_success = 0; + } + + if (!tranf_success) { + dev_dbg(&drv_data->pdev->dev, + "IO write error!\n"); + message->state = ERROR_STATE; + } else { + /* Update total byte transferred */ + message->actual_length += drv_data->len_in_bytes; + /* Move to next transfer of this msg */ + message->state = bfin_spi_next_transfer(drv_data); + if (drv_data->cs_change && message->state != DONE_STATE) { + bfin_spi_flush(drv_data); + bfin_spi_cs_deactive(drv_data, chip); + } + } + + /* Schedule next transfer tasklet */ + tasklet_schedule(&drv_data->pump_transfers); +} + +/* pop a msg from queue and kick off real transfer */ +static void bfin_spi_pump_messages(struct work_struct *work) +{ + struct bfin_spi_master_data *drv_data; + unsigned long flags; + + drv_data = container_of(work, struct bfin_spi_master_data, pump_messages); + + /* Lock queue and check for queue work */ + spin_lock_irqsave(&drv_data->lock, flags); + if (list_empty(&drv_data->queue) || !drv_data->running) { + /* pumper kicked off but no work to do */ + drv_data->busy = 0; + spin_unlock_irqrestore(&drv_data->lock, flags); + return; + } + + /* Make sure we are not already running a message */ + if (drv_data->cur_msg) { + spin_unlock_irqrestore(&drv_data->lock, flags); + return; + } + + /* Extract head of queue */ + drv_data->cur_msg = list_entry(drv_data->queue.next, + struct spi_message, queue); + + /* Setup the SSP using the per chip configuration */ + drv_data->cur_chip = spi_get_ctldata(drv_data->cur_msg->spi); + bfin_spi_restore_state(drv_data); + + list_del_init(&drv_data->cur_msg->queue); + + /* Initial message state */ + drv_data->cur_msg->state = START_STATE; + drv_data->cur_transfer = list_entry(drv_data->cur_msg->transfers.next, + struct spi_transfer, transfer_list); + + dev_dbg(&drv_data->pdev->dev, + "got a message to pump, state is set to: baud " + "%d, flag 0x%x, ctl 0x%x\n", + drv_data->cur_chip->baud, drv_data->cur_chip->flag, + drv_data->cur_chip->ctl_reg); + + dev_dbg(&drv_data->pdev->dev, + "the first transfer len is %d\n", + drv_data->cur_transfer->len); + + /* Mark as busy and launch transfers */ + tasklet_schedule(&drv_data->pump_transfers); + + drv_data->busy = 1; + spin_unlock_irqrestore(&drv_data->lock, flags); +} + +/* + * got a msg to transfer, queue it in drv_data->queue. + * And kick off message pumper + */ +static int bfin_spi_transfer(struct spi_device *spi, struct spi_message *msg) +{ + struct bfin_spi_master_data *drv_data = spi_master_get_devdata(spi->master); + unsigned long flags; + + spin_lock_irqsave(&drv_data->lock, flags); + + if (!drv_data->running) { + spin_unlock_irqrestore(&drv_data->lock, flags); + return -ESHUTDOWN; + } + + msg->actual_length = 0; + msg->status = -EINPROGRESS; + msg->state = START_STATE; + + dev_dbg(&spi->dev, "adding an msg in transfer() \n"); + list_add_tail(&msg->queue, &drv_data->queue); + + if (drv_data->running && !drv_data->busy) + queue_work(drv_data->workqueue, &drv_data->pump_messages); + + spin_unlock_irqrestore(&drv_data->lock, flags); + + return 0; +} + +#define MAX_SPI_SSEL 7 + +static const u16 ssel[][MAX_SPI_SSEL] = { + {P_SPI0_SSEL1, P_SPI0_SSEL2, P_SPI0_SSEL3, + P_SPI0_SSEL4, P_SPI0_SSEL5, + P_SPI0_SSEL6, P_SPI0_SSEL7}, + + {P_SPI1_SSEL1, P_SPI1_SSEL2, P_SPI1_SSEL3, + P_SPI1_SSEL4, P_SPI1_SSEL5, + P_SPI1_SSEL6, P_SPI1_SSEL7}, + + {P_SPI2_SSEL1, P_SPI2_SSEL2, P_SPI2_SSEL3, + P_SPI2_SSEL4, P_SPI2_SSEL5, + P_SPI2_SSEL6, P_SPI2_SSEL7}, +}; + +/* setup for devices (may be called multiple times -- not just first setup) */ +static int bfin_spi_setup(struct spi_device *spi) +{ + struct bfin5xx_spi_chip *chip_info; + struct bfin_spi_slave_data *chip = NULL; + struct bfin_spi_master_data *drv_data = spi_master_get_devdata(spi->master); + u16 bfin_ctl_reg; + int ret = -EINVAL; + + /* Only alloc (or use chip_info) on first setup */ + chip_info = NULL; + chip = spi_get_ctldata(spi); + if (chip == NULL) { + chip = kzalloc(sizeof(*chip), GFP_KERNEL); + if (!chip) { + dev_err(&spi->dev, "cannot allocate chip data\n"); + ret = -ENOMEM; + goto error; + } + + chip->enable_dma = 0; + chip_info = spi->controller_data; + } + + /* Let people set non-standard bits directly */ + bfin_ctl_reg = BIT_CTL_OPENDRAIN | BIT_CTL_EMISO | + BIT_CTL_PSSE | BIT_CTL_GM | BIT_CTL_SZ; + + /* chip_info isn't always needed */ + if (chip_info) { + /* Make sure people stop trying to set fields via ctl_reg + * when they should actually be using common SPI framework. + * Currently we let through: WOM EMISO PSSE GM SZ. + * Not sure if a user actually needs/uses any of these, + * but let's assume (for now) they do. + */ + if (chip_info->ctl_reg & ~bfin_ctl_reg) { + dev_err(&spi->dev, + "do not set bits in ctl_reg that the SPI framework manages\n"); + goto error; + } + chip->enable_dma = chip_info->enable_dma != 0 + && drv_data->master_info->enable_dma; + chip->ctl_reg = chip_info->ctl_reg; + chip->cs_chg_udelay = chip_info->cs_chg_udelay; + chip->idle_tx_val = chip_info->idle_tx_val; + chip->pio_interrupt = chip_info->pio_interrupt; + } else { + /* force a default base state */ + chip->ctl_reg &= bfin_ctl_reg; + } + + /* translate common spi framework into our register */ + if (spi->mode & SPI_CPOL) + chip->ctl_reg |= BIT_CTL_CPOL; + if (spi->mode & SPI_CPHA) + chip->ctl_reg |= BIT_CTL_CPHA; + if (spi->mode & SPI_LSB_FIRST) + chip->ctl_reg |= BIT_CTL_LSBF; + /* we dont support running in slave mode (yet?) */ + chip->ctl_reg |= BIT_CTL_MASTER; + + /* + * Notice: for blackfin, the speed_hz is the value of register + * SPI_BAUD, not the real baudrate + */ + chip->baud = hz_to_spi_baud(spi->max_speed_hz); + chip->chip_select_num = spi->chip_select; + if (chip->chip_select_num < MAX_CTRL_CS) { + if (!(spi->mode & SPI_CPHA)) + dev_warn(&spi->dev, + "Warning: SPI CPHA not set: Slave Select not under software control!\n" + "See Documentation/blackfin/bfin-spi-notes.txt\n"); + + chip->flag = (1 << spi->chip_select) << 8; + } else + chip->cs_gpio = chip->chip_select_num - MAX_CTRL_CS; + + if (chip->enable_dma && chip->pio_interrupt) { + dev_err(&spi->dev, + "enable_dma is set, do not set pio_interrupt\n"); + goto error; + } + /* + * if any one SPI chip is registered and wants DMA, request the + * DMA channel for it + */ + if (chip->enable_dma && !drv_data->dma_requested) { + /* register dma irq handler */ + ret = request_dma(drv_data->dma_channel, "BFIN_SPI_DMA"); + if (ret) { + dev_err(&spi->dev, + "Unable to request BlackFin SPI DMA channel\n"); + goto error; + } + drv_data->dma_requested = 1; + + ret = set_dma_callback(drv_data->dma_channel, + bfin_spi_dma_irq_handler, drv_data); + if (ret) { + dev_err(&spi->dev, "Unable to set dma callback\n"); + goto error; + } + dma_disable_irq(drv_data->dma_channel); + } + + if (chip->pio_interrupt && !drv_data->irq_requested) { + ret = request_irq(drv_data->spi_irq, bfin_spi_pio_irq_handler, + 0, "BFIN_SPI", drv_data); + if (ret) { + dev_err(&spi->dev, "Unable to register spi IRQ\n"); + goto error; + } + drv_data->irq_requested = 1; + /* we use write mode, spi irq has to be disabled here */ + disable_irq(drv_data->spi_irq); + } + + if (chip->chip_select_num >= MAX_CTRL_CS) { + /* Only request on first setup */ + if (spi_get_ctldata(spi) == NULL) { + ret = gpio_request(chip->cs_gpio, spi->modalias); + if (ret) { + dev_err(&spi->dev, "gpio_request() error\n"); + goto pin_error; + } + gpio_direction_output(chip->cs_gpio, 1); + } + } + + dev_dbg(&spi->dev, "setup spi chip %s, width is %d, dma is %d\n", + spi->modalias, spi->bits_per_word, chip->enable_dma); + dev_dbg(&spi->dev, "ctl_reg is 0x%x, flag_reg is 0x%x\n", + chip->ctl_reg, chip->flag); + + spi_set_ctldata(spi, chip); + + dev_dbg(&spi->dev, "chip select number is %d\n", chip->chip_select_num); + if (chip->chip_select_num < MAX_CTRL_CS) { + ret = peripheral_request(ssel[spi->master->bus_num] + [chip->chip_select_num-1], spi->modalias); + if (ret) { + dev_err(&spi->dev, "peripheral_request() error\n"); + goto pin_error; + } + } + + bfin_spi_cs_enable(drv_data, chip); + bfin_spi_cs_deactive(drv_data, chip); + + return 0; + + pin_error: + if (chip->chip_select_num >= MAX_CTRL_CS) + gpio_free(chip->cs_gpio); + else + peripheral_free(ssel[spi->master->bus_num] + [chip->chip_select_num - 1]); + error: + if (chip) { + if (drv_data->dma_requested) + free_dma(drv_data->dma_channel); + drv_data->dma_requested = 0; + + kfree(chip); + /* prevent free 'chip' twice */ + spi_set_ctldata(spi, NULL); + } + + return ret; +} + +/* + * callback for spi framework. + * clean driver specific data + */ +static void bfin_spi_cleanup(struct spi_device *spi) +{ + struct bfin_spi_slave_data *chip = spi_get_ctldata(spi); + struct bfin_spi_master_data *drv_data = spi_master_get_devdata(spi->master); + + if (!chip) + return; + + if (chip->chip_select_num < MAX_CTRL_CS) { + peripheral_free(ssel[spi->master->bus_num] + [chip->chip_select_num-1]); + bfin_spi_cs_disable(drv_data, chip); + } else + gpio_free(chip->cs_gpio); + + kfree(chip); + /* prevent free 'chip' twice */ + spi_set_ctldata(spi, NULL); +} + +static int bfin_spi_init_queue(struct bfin_spi_master_data *drv_data) +{ + INIT_LIST_HEAD(&drv_data->queue); + spin_lock_init(&drv_data->lock); + + drv_data->running = false; + drv_data->busy = 0; + + /* init transfer tasklet */ + tasklet_init(&drv_data->pump_transfers, + bfin_spi_pump_transfers, (unsigned long)drv_data); + + /* init messages workqueue */ + INIT_WORK(&drv_data->pump_messages, bfin_spi_pump_messages); + drv_data->workqueue = create_singlethread_workqueue( + dev_name(drv_data->master->dev.parent)); + if (drv_data->workqueue == NULL) + return -EBUSY; + + return 0; +} + +static int bfin_spi_start_queue(struct bfin_spi_master_data *drv_data) +{ + unsigned long flags; + + spin_lock_irqsave(&drv_data->lock, flags); + + if (drv_data->running || drv_data->busy) { + spin_unlock_irqrestore(&drv_data->lock, flags); + return -EBUSY; + } + + drv_data->running = true; + drv_data->cur_msg = NULL; + drv_data->cur_transfer = NULL; + drv_data->cur_chip = NULL; + spin_unlock_irqrestore(&drv_data->lock, flags); + + queue_work(drv_data->workqueue, &drv_data->pump_messages); + + return 0; +} + +static int bfin_spi_stop_queue(struct bfin_spi_master_data *drv_data) +{ + unsigned long flags; + unsigned limit = 500; + int status = 0; + + spin_lock_irqsave(&drv_data->lock, flags); + + /* + * This is a bit lame, but is optimized for the common execution path. + * A wait_queue on the drv_data->busy could be used, but then the common + * execution path (pump_messages) would be required to call wake_up or + * friends on every SPI message. Do this instead + */ + drv_data->running = false; + while ((!list_empty(&drv_data->queue) || drv_data->busy) && limit--) { + spin_unlock_irqrestore(&drv_data->lock, flags); + msleep(10); + spin_lock_irqsave(&drv_data->lock, flags); + } + + if (!list_empty(&drv_data->queue) || drv_data->busy) + status = -EBUSY; + + spin_unlock_irqrestore(&drv_data->lock, flags); + + return status; +} + +static int bfin_spi_destroy_queue(struct bfin_spi_master_data *drv_data) +{ + int status; + + status = bfin_spi_stop_queue(drv_data); + if (status != 0) + return status; + + destroy_workqueue(drv_data->workqueue); + + return 0; +} + +static int bfin_spi_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct bfin5xx_spi_master *platform_info; + struct spi_master *master; + struct bfin_spi_master_data *drv_data; + struct resource *res; + int status = 0; + + platform_info = dev_get_platdata(dev); + + /* Allocate master with space for drv_data */ + master = spi_alloc_master(dev, sizeof(*drv_data)); + if (!master) { + dev_err(&pdev->dev, "can not alloc spi_master\n"); + return -ENOMEM; + } + + drv_data = spi_master_get_devdata(master); + drv_data->master = master; + drv_data->master_info = platform_info; + drv_data->pdev = pdev; + drv_data->pin_req = platform_info->pin_req; + + /* the spi->mode bits supported by this driver: */ + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST; + master->bits_per_word_mask = SPI_BPW_MASK(8) | SPI_BPW_MASK(16); + master->bus_num = pdev->id; + master->num_chipselect = platform_info->num_chipselect; + master->cleanup = bfin_spi_cleanup; + master->setup = bfin_spi_setup; + master->transfer = bfin_spi_transfer; + + /* Find and map our resources */ + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (res == NULL) { + dev_err(dev, "Cannot get IORESOURCE_MEM\n"); + status = -ENOENT; + goto out_error_get_res; + } + + drv_data->regs = ioremap(res->start, resource_size(res)); + if (drv_data->regs == NULL) { + dev_err(dev, "Cannot map IO\n"); + status = -ENXIO; + goto out_error_ioremap; + } + + res = platform_get_resource(pdev, IORESOURCE_DMA, 0); + if (res == NULL) { + dev_err(dev, "No DMA channel specified\n"); + status = -ENOENT; + goto out_error_free_io; + } + drv_data->dma_channel = res->start; + + drv_data->spi_irq = platform_get_irq(pdev, 0); + if (drv_data->spi_irq < 0) { + dev_err(dev, "No spi pio irq specified\n"); + status = -ENOENT; + goto out_error_free_io; + } + + /* Initial and start queue */ + status = bfin_spi_init_queue(drv_data); + if (status != 0) { + dev_err(dev, "problem initializing queue\n"); + goto out_error_queue_alloc; + } + + status = bfin_spi_start_queue(drv_data); + if (status != 0) { + dev_err(dev, "problem starting queue\n"); + goto out_error_queue_alloc; + } + + status = peripheral_request_list(drv_data->pin_req, DRV_NAME); + if (status != 0) { + dev_err(&pdev->dev, ": Requesting Peripherals failed\n"); + goto out_error_queue_alloc; + } + + /* Reset SPI registers. If these registers were used by the boot loader, + * the sky may fall on your head if you enable the dma controller. + */ + bfin_write(&drv_data->regs->ctl, BIT_CTL_CPHA | BIT_CTL_MASTER); + bfin_write(&drv_data->regs->flg, 0xFF00); + + /* Register with the SPI framework */ + platform_set_drvdata(pdev, drv_data); + status = spi_register_master(master); + if (status != 0) { + dev_err(dev, "problem registering spi master\n"); + goto out_error_queue_alloc; + } + + dev_info(dev, "%s, Version %s, regs@%p, dma channel@%d\n", + DRV_DESC, DRV_VERSION, drv_data->regs, + drv_data->dma_channel); + return status; + +out_error_queue_alloc: + bfin_spi_destroy_queue(drv_data); +out_error_free_io: + iounmap(drv_data->regs); +out_error_ioremap: +out_error_get_res: + spi_master_put(master); + + return status; +} + +/* stop hardware and remove the driver */ +static int bfin_spi_remove(struct platform_device *pdev) +{ + struct bfin_spi_master_data *drv_data = platform_get_drvdata(pdev); + int status = 0; + + if (!drv_data) + return 0; + + /* Remove the queue */ + status = bfin_spi_destroy_queue(drv_data); + if (status != 0) + return status; + + /* Disable the SSP at the peripheral and SOC level */ + bfin_spi_disable(drv_data); + + /* Release DMA */ + if (drv_data->master_info->enable_dma) { + if (dma_channel_active(drv_data->dma_channel)) + free_dma(drv_data->dma_channel); + } + + if (drv_data->irq_requested) { + free_irq(drv_data->spi_irq, drv_data); + drv_data->irq_requested = 0; + } + + /* Disconnect from the SPI framework */ + spi_unregister_master(drv_data->master); + + peripheral_free_list(drv_data->pin_req); + + return 0; +} + +#ifdef CONFIG_PM_SLEEP +static int bfin_spi_suspend(struct device *dev) +{ + struct bfin_spi_master_data *drv_data = dev_get_drvdata(dev); + int status = 0; + + status = bfin_spi_stop_queue(drv_data); + if (status != 0) + return status; + + drv_data->ctrl_reg = bfin_read(&drv_data->regs->ctl); + drv_data->flag_reg = bfin_read(&drv_data->regs->flg); + + /* + * reset SPI_CTL and SPI_FLG registers + */ + bfin_write(&drv_data->regs->ctl, BIT_CTL_CPHA | BIT_CTL_MASTER); + bfin_write(&drv_data->regs->flg, 0xFF00); + + return 0; +} + +static int bfin_spi_resume(struct device *dev) +{ + struct bfin_spi_master_data *drv_data = dev_get_drvdata(dev); + int status = 0; + + bfin_write(&drv_data->regs->ctl, drv_data->ctrl_reg); + bfin_write(&drv_data->regs->flg, drv_data->flag_reg); + + /* Start the queue running */ + status = bfin_spi_start_queue(drv_data); + if (status != 0) { + dev_err(dev, "problem starting queue (%d)\n", status); + return status; + } + + return 0; +} + +static SIMPLE_DEV_PM_OPS(bfin_spi_pm_ops, bfin_spi_suspend, bfin_spi_resume); + +#define BFIN_SPI_PM_OPS (&bfin_spi_pm_ops) +#else +#define BFIN_SPI_PM_OPS NULL +#endif + +MODULE_ALIAS("platform:bfin-spi"); +static struct platform_driver bfin_spi_driver = { + .driver = { + .name = DRV_NAME, + .pm = BFIN_SPI_PM_OPS, + }, + .probe = bfin_spi_probe, + .remove = bfin_spi_remove, +}; + +static int __init bfin_spi_init(void) +{ + return platform_driver_register(&bfin_spi_driver); +} +subsys_initcall(bfin_spi_init); + +static void __exit bfin_spi_exit(void) +{ + platform_driver_unregister(&bfin_spi_driver); +} +module_exit(bfin_spi_exit); diff --git a/drivers/spi/spi-bitbang-txrx.h b/drivers/spi/spi-bitbang-txrx.h new file mode 100644 index 000000000..06b34e5bc --- /dev/null +++ b/drivers/spi/spi-bitbang-txrx.h @@ -0,0 +1,107 @@ +/* + * Mix this utility code with some glue code to get one of several types of + * simple SPI master driver. Two do polled word-at-a-time I/O: + * + * - GPIO/parport bitbangers. Provide chipselect() and txrx_word[](), + * expanding the per-word routines from the inline templates below. + * + * - Drivers for controllers resembling bare shift registers. Provide + * chipselect() and txrx_word[](), with custom setup()/cleanup() methods + * that use your controller's clock and chipselect registers. + * + * Some hardware works well with requests at spi_transfer scope: + * + * - Drivers leveraging smarter hardware, with fifos or DMA; or for half + * duplex (MicroWire) controllers. Provide chipselect() and txrx_bufs(), + * and custom setup()/cleanup() methods. + */ + +/* + * The code that knows what GPIO pins do what should have declared four + * functions, ideally as inlines, before including this header: + * + * void setsck(struct spi_device *, int is_on); + * void setmosi(struct spi_device *, int is_on); + * int getmiso(struct spi_device *); + * void spidelay(unsigned); + * + * setsck()'s is_on parameter is a zero/nonzero boolean. + * + * setmosi()'s is_on parameter is a zero/nonzero boolean. + * + * getmiso() is required to return 0 or 1 only. Any other value is invalid + * and will result in improper operation. + * + * A non-inlined routine would call bitbang_txrx_*() routines. The + * main loop could easily compile down to a handful of instructions, + * especially if the delay is a NOP (to run at peak speed). + * + * Since this is software, the timings may not be exactly what your board's + * chips need ... there may be several reasons you'd need to tweak timings + * in these routines, not just to make it faster or slower to match a + * particular CPU clock rate. + */ + +static inline u32 +bitbang_txrx_be_cpha0(struct spi_device *spi, + unsigned nsecs, unsigned cpol, unsigned flags, + u32 word, u8 bits) +{ + /* if (cpol == 0) this is SPI_MODE_0; else this is SPI_MODE_2 */ + + bool oldbit = !(word & 1); + /* clock starts at inactive polarity */ + for (word <<= (32 - bits); likely(bits); bits--) { + + /* setup MSB (to slave) on trailing edge */ + if ((flags & SPI_MASTER_NO_TX) == 0) { + if ((word & (1 << 31)) != oldbit) { + setmosi(spi, word & (1 << 31)); + oldbit = word & (1 << 31); + } + } + spidelay(nsecs); /* T(setup) */ + + setsck(spi, !cpol); + spidelay(nsecs); + + /* sample MSB (from slave) on leading edge */ + word <<= 1; + if ((flags & SPI_MASTER_NO_RX) == 0) + word |= getmiso(spi); + setsck(spi, cpol); + } + return word; +} + +static inline u32 +bitbang_txrx_be_cpha1(struct spi_device *spi, + unsigned nsecs, unsigned cpol, unsigned flags, + u32 word, u8 bits) +{ + /* if (cpol == 0) this is SPI_MODE_1; else this is SPI_MODE_3 */ + + bool oldbit = !(word & (1 << 31)); + /* clock starts at inactive polarity */ + for (word <<= (32 - bits); likely(bits); bits--) { + + /* setup MSB (to slave) on leading edge */ + setsck(spi, !cpol); + if ((flags & SPI_MASTER_NO_TX) == 0) { + if ((word & (1 << 31)) != oldbit) { + setmosi(spi, word & (1 << 31)); + oldbit = word & (1 << 31); + } + } + spidelay(nsecs); /* T(setup) */ + + setsck(spi, cpol); + spidelay(nsecs); + + /* sample MSB (from slave) on trailing edge */ + word <<= 1; + if ((flags & SPI_MASTER_NO_RX) == 0) + word |= getmiso(spi); + } + return word; +} diff --git a/drivers/spi/spi-bitbang.c b/drivers/spi/spi-bitbang.c new file mode 100644 index 000000000..840a4984d --- /dev/null +++ b/drivers/spi/spi-bitbang.c @@ -0,0 +1,475 @@ +/* + * polling/bitbanging SPI master controller driver utilities + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/spinlock.h> +#include <linux/workqueue.h> +#include <linux/interrupt.h> +#include <linux/module.h> +#include <linux/delay.h> +#include <linux/errno.h> +#include <linux/platform_device.h> +#include <linux/slab.h> + +#include <linux/spi/spi.h> +#include <linux/spi/spi_bitbang.h> + + +/*----------------------------------------------------------------------*/ + +/* + * FIRST PART (OPTIONAL): word-at-a-time spi_transfer support. + * Use this for GPIO or shift-register level hardware APIs. + * + * spi_bitbang_cs is in spi_device->controller_state, which is unavailable + * to glue code. These bitbang setup() and cleanup() routines are always + * used, though maybe they're called from controller-aware code. + * + * chipselect() and friends may use spi_device->controller_data and + * controller registers as appropriate. + * + * + * NOTE: SPI controller pins can often be used as GPIO pins instead, + * which means you could use a bitbang driver either to get hardware + * working quickly, or testing for differences that aren't speed related. + */ + +struct spi_bitbang_cs { + unsigned nsecs; /* (clock cycle time)/2 */ + u32 (*txrx_word)(struct spi_device *spi, unsigned nsecs, + u32 word, u8 bits); + unsigned (*txrx_bufs)(struct spi_device *, + u32 (*txrx_word)( + struct spi_device *spi, + unsigned nsecs, + u32 word, u8 bits), + unsigned, struct spi_transfer *); +}; + +static unsigned bitbang_txrx_8( + struct spi_device *spi, + u32 (*txrx_word)(struct spi_device *spi, + unsigned nsecs, + u32 word, u8 bits), + unsigned ns, + struct spi_transfer *t +) { + unsigned bits = t->bits_per_word; + unsigned count = t->len; + const u8 *tx = t->tx_buf; + u8 *rx = t->rx_buf; + + while (likely(count > 0)) { + u8 word = 0; + + if (tx) + word = *tx++; + word = txrx_word(spi, ns, word, bits); + if (rx) + *rx++ = word; + count -= 1; + } + return t->len - count; +} + +static unsigned bitbang_txrx_16( + struct spi_device *spi, + u32 (*txrx_word)(struct spi_device *spi, + unsigned nsecs, + u32 word, u8 bits), + unsigned ns, + struct spi_transfer *t +) { + unsigned bits = t->bits_per_word; + unsigned count = t->len; + const u16 *tx = t->tx_buf; + u16 *rx = t->rx_buf; + + while (likely(count > 1)) { + u16 word = 0; + + if (tx) + word = *tx++; + word = txrx_word(spi, ns, word, bits); + if (rx) + *rx++ = word; + count -= 2; + } + return t->len - count; +} + +static unsigned bitbang_txrx_32( + struct spi_device *spi, + u32 (*txrx_word)(struct spi_device *spi, + unsigned nsecs, + u32 word, u8 bits), + unsigned ns, + struct spi_transfer *t +) { + unsigned bits = t->bits_per_word; + unsigned count = t->len; + const u32 *tx = t->tx_buf; + u32 *rx = t->rx_buf; + + while (likely(count > 3)) { + u32 word = 0; + + if (tx) + word = *tx++; + word = txrx_word(spi, ns, word, bits); + if (rx) + *rx++ = word; + count -= 4; + } + return t->len - count; +} + +int spi_bitbang_setup_transfer(struct spi_device *spi, struct spi_transfer *t) +{ + struct spi_bitbang_cs *cs = spi->controller_state; + u8 bits_per_word; + u32 hz; + + if (t) { + bits_per_word = t->bits_per_word; + hz = t->speed_hz; + } else { + bits_per_word = 0; + hz = 0; + } + + /* spi_transfer level calls that work per-word */ + if (!bits_per_word) + bits_per_word = spi->bits_per_word; + if (bits_per_word <= 8) + cs->txrx_bufs = bitbang_txrx_8; + else if (bits_per_word <= 16) + cs->txrx_bufs = bitbang_txrx_16; + else if (bits_per_word <= 32) + cs->txrx_bufs = bitbang_txrx_32; + else + return -EINVAL; + + /* nsecs = (clock period)/2 */ + if (!hz) + hz = spi->max_speed_hz; + if (hz) { + cs->nsecs = (1000000000/2) / hz; + if (cs->nsecs > (MAX_UDELAY_MS * 1000 * 1000)) + return -EINVAL; + } + + return 0; +} +EXPORT_SYMBOL_GPL(spi_bitbang_setup_transfer); + +/** + * spi_bitbang_setup - default setup for per-word I/O loops + */ +int spi_bitbang_setup(struct spi_device *spi) +{ + struct spi_bitbang_cs *cs = spi->controller_state; + struct spi_bitbang *bitbang; + unsigned long flags; + + bitbang = spi_master_get_devdata(spi->master); + + if (!cs) { + cs = kzalloc(sizeof(*cs), GFP_KERNEL); + if (!cs) + return -ENOMEM; + spi->controller_state = cs; + } + + /* per-word shift register access, in hardware or bitbanging */ + cs->txrx_word = bitbang->txrx_word[spi->mode & (SPI_CPOL|SPI_CPHA)]; + if (!cs->txrx_word) + return -EINVAL; + + if (bitbang->setup_transfer) { + int retval = bitbang->setup_transfer(spi, NULL); + if (retval < 0) + return retval; + } + + dev_dbg(&spi->dev, "%s, %u nsec/bit\n", __func__, 2 * cs->nsecs); + + /* NOTE we _need_ to call chipselect() early, ideally with adapter + * setup, unless the hardware defaults cooperate to avoid confusion + * between normal (active low) and inverted chipselects. + */ + + /* deselect chip (low or high) */ + spin_lock_irqsave(&bitbang->lock, flags); + if (!bitbang->busy) { + bitbang->chipselect(spi, BITBANG_CS_INACTIVE); + ndelay(cs->nsecs); + } + spin_unlock_irqrestore(&bitbang->lock, flags); + + return 0; +} +EXPORT_SYMBOL_GPL(spi_bitbang_setup); + +/** + * spi_bitbang_cleanup - default cleanup for per-word I/O loops + */ +void spi_bitbang_cleanup(struct spi_device *spi) +{ + kfree(spi->controller_state); +} +EXPORT_SYMBOL_GPL(spi_bitbang_cleanup); + +static int spi_bitbang_bufs(struct spi_device *spi, struct spi_transfer *t) +{ + struct spi_bitbang_cs *cs = spi->controller_state; + unsigned nsecs = cs->nsecs; + + return cs->txrx_bufs(spi, cs->txrx_word, nsecs, t); +} + +/*----------------------------------------------------------------------*/ + +/* + * SECOND PART ... simple transfer queue runner. + * + * This costs a task context per controller, running the queue by + * performing each transfer in sequence. Smarter hardware can queue + * several DMA transfers at once, and process several controller queues + * in parallel; this driver doesn't match such hardware very well. + * + * Drivers can provide word-at-a-time i/o primitives, or provide + * transfer-at-a-time ones to leverage dma or fifo hardware. + */ + +static int spi_bitbang_prepare_hardware(struct spi_master *spi) +{ + struct spi_bitbang *bitbang; + unsigned long flags; + + bitbang = spi_master_get_devdata(spi); + + spin_lock_irqsave(&bitbang->lock, flags); + bitbang->busy = 1; + spin_unlock_irqrestore(&bitbang->lock, flags); + + return 0; +} + +static int spi_bitbang_transfer_one(struct spi_master *master, + struct spi_message *m) +{ + struct spi_bitbang *bitbang; + unsigned nsecs; + struct spi_transfer *t = NULL; + unsigned cs_change; + int status; + int do_setup = -1; + struct spi_device *spi = m->spi; + + bitbang = spi_master_get_devdata(master); + + /* FIXME this is made-up ... the correct value is known to + * word-at-a-time bitbang code, and presumably chipselect() + * should enforce these requirements too? + */ + nsecs = 100; + + cs_change = 1; + status = 0; + + list_for_each_entry(t, &m->transfers, transfer_list) { + + /* override speed or wordsize? */ + if (t->speed_hz || t->bits_per_word) + do_setup = 1; + + /* init (-1) or override (1) transfer params */ + if (do_setup != 0) { + if (bitbang->setup_transfer) { + status = bitbang->setup_transfer(spi, t); + if (status < 0) + break; + } + if (do_setup == -1) + do_setup = 0; + } + + /* set up default clock polarity, and activate chip; + * this implicitly updates clock and spi modes as + * previously recorded for this device via setup(). + * (and also deselects any other chip that might be + * selected ...) + */ + if (cs_change) { + bitbang->chipselect(spi, BITBANG_CS_ACTIVE); + ndelay(nsecs); + } + cs_change = t->cs_change; + if (!t->tx_buf && !t->rx_buf && t->len) { + status = -EINVAL; + break; + } + + /* transfer data. the lower level code handles any + * new dma mappings it needs. our caller always gave + * us dma-safe buffers. + */ + if (t->len) { + /* REVISIT dma API still needs a designated + * DMA_ADDR_INVALID; ~0 might be better. + */ + if (!m->is_dma_mapped) + t->rx_dma = t->tx_dma = 0; + status = bitbang->txrx_bufs(spi, t); + } + if (status > 0) + m->actual_length += status; + if (status != t->len) { + /* always report some kind of error */ + if (status >= 0) + status = -EREMOTEIO; + break; + } + status = 0; + + /* protocol tweaks before next transfer */ + if (t->delay_usecs) + udelay(t->delay_usecs); + + if (cs_change && + !list_is_last(&t->transfer_list, &m->transfers)) { + /* sometimes a short mid-message deselect of the chip + * may be needed to terminate a mode or command + */ + ndelay(nsecs); + bitbang->chipselect(spi, BITBANG_CS_INACTIVE); + ndelay(nsecs); + } + } + + m->status = status; + + /* normally deactivate chipselect ... unless no error and + * cs_change has hinted that the next message will probably + * be for this chip too. + */ + if (!(status == 0 && cs_change)) { + ndelay(nsecs); + bitbang->chipselect(spi, BITBANG_CS_INACTIVE); + ndelay(nsecs); + } + + spi_finalize_current_message(master); + + return status; +} + +static int spi_bitbang_unprepare_hardware(struct spi_master *spi) +{ + struct spi_bitbang *bitbang; + unsigned long flags; + + bitbang = spi_master_get_devdata(spi); + + spin_lock_irqsave(&bitbang->lock, flags); + bitbang->busy = 0; + spin_unlock_irqrestore(&bitbang->lock, flags); + + return 0; +} + +/*----------------------------------------------------------------------*/ + +/** + * spi_bitbang_start - start up a polled/bitbanging SPI master driver + * @bitbang: driver handle + * + * Caller should have zero-initialized all parts of the structure, and then + * provided callbacks for chip selection and I/O loops. If the master has + * a transfer method, its final step should call spi_bitbang_transfer; or, + * that's the default if the transfer routine is not initialized. It should + * also set up the bus number and number of chipselects. + * + * For i/o loops, provide callbacks either per-word (for bitbanging, or for + * hardware that basically exposes a shift register) or per-spi_transfer + * (which takes better advantage of hardware like fifos or DMA engines). + * + * Drivers using per-word I/O loops should use (or call) spi_bitbang_setup, + * spi_bitbang_cleanup and spi_bitbang_setup_transfer to handle those spi + * master methods. Those methods are the defaults if the bitbang->txrx_bufs + * routine isn't initialized. + * + * This routine registers the spi_master, which will process requests in a + * dedicated task, keeping IRQs unblocked most of the time. To stop + * processing those requests, call spi_bitbang_stop(). + * + * On success, this routine will take a reference to master. The caller is + * responsible for calling spi_bitbang_stop() to decrement the reference and + * spi_master_put() as counterpart of spi_alloc_master() to prevent a memory + * leak. + */ +int spi_bitbang_start(struct spi_bitbang *bitbang) +{ + struct spi_master *master = bitbang->master; + int ret; + + if (!master || !bitbang->chipselect) + return -EINVAL; + + spin_lock_init(&bitbang->lock); + + if (!master->mode_bits) + master->mode_bits = SPI_CPOL | SPI_CPHA | bitbang->flags; + + if (master->transfer || master->transfer_one_message) + return -EINVAL; + + master->prepare_transfer_hardware = spi_bitbang_prepare_hardware; + master->unprepare_transfer_hardware = spi_bitbang_unprepare_hardware; + master->transfer_one_message = spi_bitbang_transfer_one; + + if (!bitbang->txrx_bufs) { + bitbang->use_dma = 0; + bitbang->txrx_bufs = spi_bitbang_bufs; + if (!master->setup) { + if (!bitbang->setup_transfer) + bitbang->setup_transfer = + spi_bitbang_setup_transfer; + master->setup = spi_bitbang_setup; + master->cleanup = spi_bitbang_cleanup; + } + } + + /* driver may get busy before register() returns, especially + * if someone registered boardinfo for devices + */ + ret = spi_register_master(spi_master_get(master)); + if (ret) + spi_master_put(master); + + return 0; +} +EXPORT_SYMBOL_GPL(spi_bitbang_start); + +/** + * spi_bitbang_stop - stops the task providing spi communication + */ +void spi_bitbang_stop(struct spi_bitbang *bitbang) +{ + spi_unregister_master(bitbang->master); +} +EXPORT_SYMBOL_GPL(spi_bitbang_stop); + +MODULE_LICENSE("GPL"); + diff --git a/drivers/spi/spi-butterfly.c b/drivers/spi/spi-butterfly.c new file mode 100644 index 000000000..9a9586298 --- /dev/null +++ b/drivers/spi/spi-butterfly.c @@ -0,0 +1,351 @@ +/* + * parport-to-butterfly adapter + * + * Copyright (C) 2005 David Brownell + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/delay.h> +#include <linux/module.h> +#include <linux/device.h> +#include <linux/parport.h> + +#include <linux/sched.h> +#include <linux/spi/spi.h> +#include <linux/spi/spi_bitbang.h> +#include <linux/spi/flash.h> + +#include <linux/mtd/partitions.h> + + +/* + * This uses SPI to talk with an "AVR Butterfly", which is a $US20 card + * with a battery powered AVR microcontroller and lots of goodies. You + * can use GCC to develop firmware for this. + * + * See Documentation/spi/butterfly for information about how to build + * and use this custom parallel port cable. + */ + + +/* DATA output bits (pins 2..9 == D0..D7) */ +#define butterfly_nreset (1 << 1) /* pin 3 */ + +#define spi_sck_bit (1 << 0) /* pin 2 */ +#define spi_mosi_bit (1 << 7) /* pin 9 */ + +#define vcc_bits ((1 << 6) | (1 << 5)) /* pins 7, 8 */ + +/* STATUS input bits */ +#define spi_miso_bit PARPORT_STATUS_BUSY /* pin 11 */ + +/* CONTROL output bits */ +#define spi_cs_bit PARPORT_CONTROL_SELECT /* pin 17 */ + + + +static inline struct butterfly *spidev_to_pp(struct spi_device *spi) +{ + return spi->controller_data; +} + + +struct butterfly { + /* REVISIT ... for now, this must be first */ + struct spi_bitbang bitbang; + + struct parport *port; + struct pardevice *pd; + + u8 lastbyte; + + struct spi_device *dataflash; + struct spi_device *butterfly; + struct spi_board_info info[2]; + +}; + +/*----------------------------------------------------------------------*/ + +static inline void +setsck(struct spi_device *spi, int is_on) +{ + struct butterfly *pp = spidev_to_pp(spi); + u8 bit, byte = pp->lastbyte; + + bit = spi_sck_bit; + + if (is_on) + byte |= bit; + else + byte &= ~bit; + parport_write_data(pp->port, byte); + pp->lastbyte = byte; +} + +static inline void +setmosi(struct spi_device *spi, int is_on) +{ + struct butterfly *pp = spidev_to_pp(spi); + u8 bit, byte = pp->lastbyte; + + bit = spi_mosi_bit; + + if (is_on) + byte |= bit; + else + byte &= ~bit; + parport_write_data(pp->port, byte); + pp->lastbyte = byte; +} + +static inline int getmiso(struct spi_device *spi) +{ + struct butterfly *pp = spidev_to_pp(spi); + int value; + u8 bit; + + bit = spi_miso_bit; + + /* only STATUS_BUSY is NOT negated */ + value = !(parport_read_status(pp->port) & bit); + return (bit == PARPORT_STATUS_BUSY) ? value : !value; +} + +static void butterfly_chipselect(struct spi_device *spi, int value) +{ + struct butterfly *pp = spidev_to_pp(spi); + + /* set default clock polarity */ + if (value != BITBANG_CS_INACTIVE) + setsck(spi, spi->mode & SPI_CPOL); + + /* here, value == "activate or not"; + * most PARPORT_CONTROL_* bits are negated, so we must + * morph it to value == "bit value to write in control register" + */ + if (spi_cs_bit == PARPORT_CONTROL_INIT) + value = !value; + + parport_frob_control(pp->port, spi_cs_bit, value ? spi_cs_bit : 0); +} + + +/* we only needed to implement one mode here, and choose SPI_MODE_0 */ + +#define spidelay(X) do { } while (0) +/* #define spidelay ndelay */ + +#include "spi-bitbang-txrx.h" + +static u32 +butterfly_txrx_word_mode0(struct spi_device *spi, + unsigned nsecs, + u32 word, u8 bits) +{ + return bitbang_txrx_be_cpha0(spi, nsecs, 0, 0, word, bits); +} + +/*----------------------------------------------------------------------*/ + +/* override default partitioning with cmdlinepart */ +static struct mtd_partition partitions[] = { { + /* JFFS2 wants partitions of 4*N blocks for this device, + * so sectors 0 and 1 can't be partitions by themselves. + */ + + /* sector 0 = 8 pages * 264 bytes/page (1 block) + * sector 1 = 248 pages * 264 bytes/page + */ + .name = "bookkeeping", /* 66 KB */ + .offset = 0, + .size = (8 + 248) * 264, + /* .mask_flags = MTD_WRITEABLE, */ +}, { + /* sector 2 = 256 pages * 264 bytes/page + * sectors 3-5 = 512 pages * 264 bytes/page + */ + .name = "filesystem", /* 462 KB */ + .offset = MTDPART_OFS_APPEND, + .size = MTDPART_SIZ_FULL, +} }; + +static struct flash_platform_data flash = { + .name = "butterflash", + .parts = partitions, + .nr_parts = ARRAY_SIZE(partitions), +}; + + +/* REVISIT remove this ugly global and its "only one" limitation */ +static struct butterfly *butterfly; + +static void butterfly_attach(struct parport *p) +{ + struct pardevice *pd; + int status; + struct butterfly *pp; + struct spi_master *master; + struct device *dev = p->physport->dev; + + if (butterfly || !dev) + return; + + /* REVISIT: this just _assumes_ a butterfly is there ... no probe, + * and no way to be selective about what it binds to. + */ + + master = spi_alloc_master(dev, sizeof(*pp)); + if (!master) { + status = -ENOMEM; + goto done; + } + pp = spi_master_get_devdata(master); + + /* + * SPI and bitbang hookup + * + * use default setup(), cleanup(), and transfer() methods; and + * only bother implementing mode 0. Start it later. + */ + master->bus_num = 42; + master->num_chipselect = 2; + + pp->bitbang.master = master; + pp->bitbang.chipselect = butterfly_chipselect; + pp->bitbang.txrx_word[SPI_MODE_0] = butterfly_txrx_word_mode0; + + /* + * parport hookup + */ + pp->port = p; + pd = parport_register_device(p, "spi_butterfly", + NULL, NULL, NULL, + 0 /* FLAGS */, pp); + if (!pd) { + status = -ENOMEM; + goto clean0; + } + pp->pd = pd; + + status = parport_claim(pd); + if (status < 0) + goto clean1; + + /* + * Butterfly reset, powerup, run firmware + */ + pr_debug("%s: powerup/reset Butterfly\n", p->name); + + /* nCS for dataflash (this bit is inverted on output) */ + parport_frob_control(pp->port, spi_cs_bit, 0); + + /* stabilize power with chip in reset (nRESET), and + * spi_sck_bit clear (CPOL=0) + */ + pp->lastbyte |= vcc_bits; + parport_write_data(pp->port, pp->lastbyte); + msleep(5); + + /* take it out of reset; assume long reset delay */ + pp->lastbyte |= butterfly_nreset; + parport_write_data(pp->port, pp->lastbyte); + msleep(100); + + + /* + * Start SPI ... for now, hide that we're two physical busses. + */ + status = spi_bitbang_start(&pp->bitbang); + if (status < 0) + goto clean2; + + /* Bus 1 lets us talk to at45db041b (firmware disables AVR SPI), AVR + * (firmware resets at45, acts as spi slave) or neither (we ignore + * both, AVR uses AT45). Here we expect firmware for the first option. + */ + + pp->info[0].max_speed_hz = 15 * 1000 * 1000; + strcpy(pp->info[0].modalias, "mtd_dataflash"); + pp->info[0].platform_data = &flash; + pp->info[0].chip_select = 1; + pp->info[0].controller_data = pp; + pp->dataflash = spi_new_device(pp->bitbang.master, &pp->info[0]); + if (pp->dataflash) + pr_debug("%s: dataflash at %s\n", p->name, + dev_name(&pp->dataflash->dev)); + + pr_info("%s: AVR Butterfly\n", p->name); + butterfly = pp; + return; + +clean2: + /* turn off VCC */ + parport_write_data(pp->port, 0); + + parport_release(pp->pd); +clean1: + parport_unregister_device(pd); +clean0: + (void) spi_master_put(pp->bitbang.master); +done: + pr_debug("%s: butterfly probe, fail %d\n", p->name, status); +} + +static void butterfly_detach(struct parport *p) +{ + struct butterfly *pp; + + /* FIXME this global is ugly ... but, how to quickly get from + * the parport to the "struct butterfly" associated with it? + * "old school" driver-internal device lists? + */ + if (!butterfly || butterfly->port != p) + return; + pp = butterfly; + butterfly = NULL; + + /* stop() unregisters child devices too */ + spi_bitbang_stop(&pp->bitbang); + + /* turn off VCC */ + parport_write_data(pp->port, 0); + msleep(10); + + parport_release(pp->pd); + parport_unregister_device(pp->pd); + + (void) spi_master_put(pp->bitbang.master); +} + +static struct parport_driver butterfly_driver = { + .name = "spi_butterfly", + .attach = butterfly_attach, + .detach = butterfly_detach, +}; + + +static int __init butterfly_init(void) +{ + return parport_register_driver(&butterfly_driver); +} +device_initcall(butterfly_init); + +static void __exit butterfly_exit(void) +{ + parport_unregister_driver(&butterfly_driver); +} +module_exit(butterfly_exit); + +MODULE_DESCRIPTION("Parport Adapter driver for AVR Butterfly"); +MODULE_LICENSE("GPL"); diff --git a/drivers/spi/spi-cadence.c b/drivers/spi/spi-cadence.c new file mode 100644 index 000000000..5a6749881 --- /dev/null +++ b/drivers/spi/spi-cadence.c @@ -0,0 +1,692 @@ +/* + * Cadence SPI controller driver (master mode only) + * + * Copyright (C) 2008 - 2014 Xilinx, Inc. + * + * based on Blackfin On-Chip SPI Driver (spi_bfin5xx.c) + * + * This program is free software; you can redistribute it and/or modify it under + * the terms of the GNU General Public License version 2 as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + */ + +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/of_irq.h> +#include <linux/of_address.h> +#include <linux/platform_device.h> +#include <linux/spi/spi.h> + +/* Name of this driver */ +#define CDNS_SPI_NAME "cdns-spi" + +/* Register offset definitions */ +#define CDNS_SPI_CR_OFFSET 0x00 /* Configuration Register, RW */ +#define CDNS_SPI_ISR_OFFSET 0x04 /* Interrupt Status Register, RO */ +#define CDNS_SPI_IER_OFFSET 0x08 /* Interrupt Enable Register, WO */ +#define CDNS_SPI_IDR_OFFSET 0x0c /* Interrupt Disable Register, WO */ +#define CDNS_SPI_IMR_OFFSET 0x10 /* Interrupt Enabled Mask Register, RO */ +#define CDNS_SPI_ER_OFFSET 0x14 /* Enable/Disable Register, RW */ +#define CDNS_SPI_DR_OFFSET 0x18 /* Delay Register, RW */ +#define CDNS_SPI_TXD_OFFSET 0x1C /* Data Transmit Register, WO */ +#define CDNS_SPI_RXD_OFFSET 0x20 /* Data Receive Register, RO */ +#define CDNS_SPI_SICR_OFFSET 0x24 /* Slave Idle Count Register, RW */ +#define CDNS_SPI_THLD_OFFSET 0x28 /* Transmit FIFO Watermark Register,RW */ + +/* + * SPI Configuration Register bit Masks + * + * This register contains various control bits that affect the operation + * of the SPI controller + */ +#define CDNS_SPI_CR_MANSTRT_MASK 0x00010000 /* Manual TX Start */ +#define CDNS_SPI_CR_CPHA_MASK 0x00000004 /* Clock Phase Control */ +#define CDNS_SPI_CR_CPOL_MASK 0x00000002 /* Clock Polarity Control */ +#define CDNS_SPI_CR_SSCTRL_MASK 0x00003C00 /* Slave Select Mask */ +#define CDNS_SPI_CR_PERI_SEL_MASK 0x00000200 /* Peripheral Select Decode */ +#define CDNS_SPI_CR_BAUD_DIV_MASK 0x00000038 /* Baud Rate Divisor Mask */ +#define CDNS_SPI_CR_MSTREN_MASK 0x00000001 /* Master Enable Mask */ +#define CDNS_SPI_CR_MANSTRTEN_MASK 0x00008000 /* Manual TX Enable Mask */ +#define CDNS_SPI_CR_SSFORCE_MASK 0x00004000 /* Manual SS Enable Mask */ +#define CDNS_SPI_CR_BAUD_DIV_4_MASK 0x00000008 /* Default Baud Div Mask */ +#define CDNS_SPI_CR_DEFAULT_MASK (CDNS_SPI_CR_MSTREN_MASK | \ + CDNS_SPI_CR_SSCTRL_MASK | \ + CDNS_SPI_CR_SSFORCE_MASK | \ + CDNS_SPI_CR_BAUD_DIV_4_MASK) + +/* + * SPI Configuration Register - Baud rate and slave select + * + * These are the values used in the calculation of baud rate divisor and + * setting the slave select. + */ + +#define CDNS_SPI_BAUD_DIV_MAX 7 /* Baud rate divisor maximum */ +#define CDNS_SPI_BAUD_DIV_MIN 1 /* Baud rate divisor minimum */ +#define CDNS_SPI_BAUD_DIV_SHIFT 3 /* Baud rate divisor shift in CR */ +#define CDNS_SPI_SS_SHIFT 10 /* Slave Select field shift in CR */ +#define CDNS_SPI_SS0 0x1 /* Slave Select zero */ + +/* + * SPI Interrupt Registers bit Masks + * + * All the four interrupt registers (Status/Mask/Enable/Disable) have the same + * bit definitions. + */ +#define CDNS_SPI_IXR_TXOW_MASK 0x00000004 /* SPI TX FIFO Overwater */ +#define CDNS_SPI_IXR_MODF_MASK 0x00000002 /* SPI Mode Fault */ +#define CDNS_SPI_IXR_RXNEMTY_MASK 0x00000010 /* SPI RX FIFO Not Empty */ +#define CDNS_SPI_IXR_DEFAULT_MASK (CDNS_SPI_IXR_TXOW_MASK | \ + CDNS_SPI_IXR_MODF_MASK) +#define CDNS_SPI_IXR_TXFULL_MASK 0x00000008 /* SPI TX Full */ +#define CDNS_SPI_IXR_ALL_MASK 0x0000007F /* SPI all interrupts */ + +/* + * SPI Enable Register bit Masks + * + * This register is used to enable or disable the SPI controller + */ +#define CDNS_SPI_ER_ENABLE_MASK 0x00000001 /* SPI Enable Bit Mask */ +#define CDNS_SPI_ER_DISABLE_MASK 0x0 /* SPI Disable Bit Mask */ + +/* SPI FIFO depth in bytes */ +#define CDNS_SPI_FIFO_DEPTH 128 + +/* Default number of chip select lines */ +#define CDNS_SPI_DEFAULT_NUM_CS 4 + +/** + * struct cdns_spi - This definition defines spi driver instance + * @regs: Virtual address of the SPI controller registers + * @ref_clk: Pointer to the peripheral clock + * @pclk: Pointer to the APB clock + * @speed_hz: Current SPI bus clock speed in Hz + * @txbuf: Pointer to the TX buffer + * @rxbuf: Pointer to the RX buffer + * @tx_bytes: Number of bytes left to transfer + * @rx_bytes: Number of bytes requested + * @dev_busy: Device busy flag + * @is_decoded_cs: Flag for decoder property set or not + */ +struct cdns_spi { + void __iomem *regs; + struct clk *ref_clk; + struct clk *pclk; + u32 speed_hz; + const u8 *txbuf; + u8 *rxbuf; + int tx_bytes; + int rx_bytes; + u8 dev_busy; + u32 is_decoded_cs; +}; + +/* Macros for the SPI controller read/write */ +static inline u32 cdns_spi_read(struct cdns_spi *xspi, u32 offset) +{ + return readl_relaxed(xspi->regs + offset); +} + +static inline void cdns_spi_write(struct cdns_spi *xspi, u32 offset, u32 val) +{ + writel_relaxed(val, xspi->regs + offset); +} + +/** + * cdns_spi_init_hw - Initialize the hardware and configure the SPI controller + * @xspi: Pointer to the cdns_spi structure + * + * On reset the SPI controller is configured to be in master mode, baud rate + * divisor is set to 4, threshold value for TX FIFO not full interrupt is set + * to 1 and size of the word to be transferred as 8 bit. + * This function initializes the SPI controller to disable and clear all the + * interrupts, enable manual slave select and manual start, deselect all the + * chip select lines, and enable the SPI controller. + */ +static void cdns_spi_init_hw(struct cdns_spi *xspi) +{ + u32 ctrl_reg = CDNS_SPI_CR_DEFAULT_MASK; + + if (xspi->is_decoded_cs) + ctrl_reg |= CDNS_SPI_CR_PERI_SEL_MASK; + + cdns_spi_write(xspi, CDNS_SPI_ER_OFFSET, + CDNS_SPI_ER_DISABLE_MASK); + cdns_spi_write(xspi, CDNS_SPI_IDR_OFFSET, + CDNS_SPI_IXR_ALL_MASK); + + /* Clear the RX FIFO */ + while (cdns_spi_read(xspi, CDNS_SPI_ISR_OFFSET) & + CDNS_SPI_IXR_RXNEMTY_MASK) + cdns_spi_read(xspi, CDNS_SPI_RXD_OFFSET); + + cdns_spi_write(xspi, CDNS_SPI_ISR_OFFSET, + CDNS_SPI_IXR_ALL_MASK); + cdns_spi_write(xspi, CDNS_SPI_CR_OFFSET, ctrl_reg); + cdns_spi_write(xspi, CDNS_SPI_ER_OFFSET, + CDNS_SPI_ER_ENABLE_MASK); +} + +/** + * cdns_spi_chipselect - Select or deselect the chip select line + * @spi: Pointer to the spi_device structure + * @is_on: Select(0) or deselect (1) the chip select line + */ +static void cdns_spi_chipselect(struct spi_device *spi, bool is_high) +{ + struct cdns_spi *xspi = spi_master_get_devdata(spi->master); + u32 ctrl_reg; + + ctrl_reg = cdns_spi_read(xspi, CDNS_SPI_CR_OFFSET); + + if (is_high) { + /* Deselect the slave */ + ctrl_reg |= CDNS_SPI_CR_SSCTRL_MASK; + } else { + /* Select the slave */ + ctrl_reg &= ~CDNS_SPI_CR_SSCTRL_MASK; + if (!(xspi->is_decoded_cs)) + ctrl_reg |= ((~(CDNS_SPI_SS0 << spi->chip_select)) << + CDNS_SPI_SS_SHIFT) & + CDNS_SPI_CR_SSCTRL_MASK; + else + ctrl_reg |= (spi->chip_select << CDNS_SPI_SS_SHIFT) & + CDNS_SPI_CR_SSCTRL_MASK; + } + + cdns_spi_write(xspi, CDNS_SPI_CR_OFFSET, ctrl_reg); +} + +/** + * cdns_spi_config_clock_mode - Sets clock polarity and phase + * @spi: Pointer to the spi_device structure + * + * Sets the requested clock polarity and phase. + */ +static void cdns_spi_config_clock_mode(struct spi_device *spi) +{ + struct cdns_spi *xspi = spi_master_get_devdata(spi->master); + u32 ctrl_reg, new_ctrl_reg; + + new_ctrl_reg = ctrl_reg = cdns_spi_read(xspi, CDNS_SPI_CR_OFFSET); + + /* Set the SPI clock phase and clock polarity */ + new_ctrl_reg &= ~(CDNS_SPI_CR_CPHA_MASK | CDNS_SPI_CR_CPOL_MASK); + if (spi->mode & SPI_CPHA) + new_ctrl_reg |= CDNS_SPI_CR_CPHA_MASK; + if (spi->mode & SPI_CPOL) + new_ctrl_reg |= CDNS_SPI_CR_CPOL_MASK; + + if (new_ctrl_reg != ctrl_reg) { + /* + * Just writing the CR register does not seem to apply the clock + * setting changes. This is problematic when changing the clock + * polarity as it will cause the SPI slave to see spurious clock + * transitions. To workaround the issue toggle the ER register. + */ + cdns_spi_write(xspi, CDNS_SPI_ER_OFFSET, + CDNS_SPI_ER_DISABLE_MASK); + cdns_spi_write(xspi, CDNS_SPI_CR_OFFSET, new_ctrl_reg); + cdns_spi_write(xspi, CDNS_SPI_ER_OFFSET, + CDNS_SPI_ER_ENABLE_MASK); + } +} + +/** + * cdns_spi_config_clock_freq - Sets clock frequency + * @spi: Pointer to the spi_device structure + * @transfer: Pointer to the spi_transfer structure which provides + * information about next transfer setup parameters + * + * Sets the requested clock frequency. + * Note: If the requested frequency is not an exact match with what can be + * obtained using the prescalar value the driver sets the clock frequency which + * is lower than the requested frequency (maximum lower) for the transfer. If + * the requested frequency is higher or lower than that is supported by the SPI + * controller the driver will set the highest or lowest frequency supported by + * controller. + */ +static void cdns_spi_config_clock_freq(struct spi_device *spi, + struct spi_transfer *transfer) +{ + struct cdns_spi *xspi = spi_master_get_devdata(spi->master); + u32 ctrl_reg, baud_rate_val; + unsigned long frequency; + + frequency = clk_get_rate(xspi->ref_clk); + + ctrl_reg = cdns_spi_read(xspi, CDNS_SPI_CR_OFFSET); + + /* Set the clock frequency */ + if (xspi->speed_hz != transfer->speed_hz) { + /* first valid value is 1 */ + baud_rate_val = CDNS_SPI_BAUD_DIV_MIN; + while ((baud_rate_val < CDNS_SPI_BAUD_DIV_MAX) && + (frequency / (2 << baud_rate_val)) > transfer->speed_hz) + baud_rate_val++; + + ctrl_reg &= ~CDNS_SPI_CR_BAUD_DIV_MASK; + ctrl_reg |= baud_rate_val << CDNS_SPI_BAUD_DIV_SHIFT; + + xspi->speed_hz = frequency / (2 << baud_rate_val); + } + cdns_spi_write(xspi, CDNS_SPI_CR_OFFSET, ctrl_reg); +} + +/** + * cdns_spi_setup_transfer - Configure SPI controller for specified transfer + * @spi: Pointer to the spi_device structure + * @transfer: Pointer to the spi_transfer structure which provides + * information about next transfer setup parameters + * + * Sets the operational mode of SPI controller for the next SPI transfer and + * sets the requested clock frequency. + * + * Return: Always 0 + */ +static int cdns_spi_setup_transfer(struct spi_device *spi, + struct spi_transfer *transfer) +{ + struct cdns_spi *xspi = spi_master_get_devdata(spi->master); + + cdns_spi_config_clock_freq(spi, transfer); + + dev_dbg(&spi->dev, "%s, mode %d, %u bits/w, %u clock speed\n", + __func__, spi->mode, spi->bits_per_word, + xspi->speed_hz); + + return 0; +} + +/** + * cdns_spi_fill_tx_fifo - Fills the TX FIFO with as many bytes as possible + * @xspi: Pointer to the cdns_spi structure + */ +static void cdns_spi_fill_tx_fifo(struct cdns_spi *xspi) +{ + unsigned long trans_cnt = 0; + + while ((trans_cnt < CDNS_SPI_FIFO_DEPTH) && + (xspi->tx_bytes > 0)) { + if (xspi->txbuf) + cdns_spi_write(xspi, CDNS_SPI_TXD_OFFSET, + *xspi->txbuf++); + else + cdns_spi_write(xspi, CDNS_SPI_TXD_OFFSET, 0); + + xspi->tx_bytes--; + trans_cnt++; + } +} + +/** + * cdns_spi_irq - Interrupt service routine of the SPI controller + * @irq: IRQ number + * @dev_id: Pointer to the xspi structure + * + * This function handles TX empty and Mode Fault interrupts only. + * On TX empty interrupt this function reads the received data from RX FIFO and + * fills the TX FIFO if there is any data remaining to be transferred. + * On Mode Fault interrupt this function indicates that transfer is completed, + * the SPI subsystem will identify the error as the remaining bytes to be + * transferred is non-zero. + * + * Return: IRQ_HANDLED when handled; IRQ_NONE otherwise. + */ +static irqreturn_t cdns_spi_irq(int irq, void *dev_id) +{ + struct spi_master *master = dev_id; + struct cdns_spi *xspi = spi_master_get_devdata(master); + u32 intr_status, status; + + status = IRQ_NONE; + intr_status = cdns_spi_read(xspi, CDNS_SPI_ISR_OFFSET); + cdns_spi_write(xspi, CDNS_SPI_ISR_OFFSET, intr_status); + + if (intr_status & CDNS_SPI_IXR_MODF_MASK) { + /* Indicate that transfer is completed, the SPI subsystem will + * identify the error as the remaining bytes to be + * transferred is non-zero + */ + cdns_spi_write(xspi, CDNS_SPI_IDR_OFFSET, + CDNS_SPI_IXR_DEFAULT_MASK); + spi_finalize_current_transfer(master); + status = IRQ_HANDLED; + } else if (intr_status & CDNS_SPI_IXR_TXOW_MASK) { + unsigned long trans_cnt; + + trans_cnt = xspi->rx_bytes - xspi->tx_bytes; + + /* Read out the data from the RX FIFO */ + while (trans_cnt) { + u8 data; + + data = cdns_spi_read(xspi, CDNS_SPI_RXD_OFFSET); + if (xspi->rxbuf) + *xspi->rxbuf++ = data; + + xspi->rx_bytes--; + trans_cnt--; + } + + if (xspi->tx_bytes) { + /* There is more data to send */ + cdns_spi_fill_tx_fifo(xspi); + } else { + /* Transfer is completed */ + cdns_spi_write(xspi, CDNS_SPI_IDR_OFFSET, + CDNS_SPI_IXR_DEFAULT_MASK); + spi_finalize_current_transfer(master); + } + status = IRQ_HANDLED; + } + + return status; +} +static int cdns_prepare_message(struct spi_master *master, + struct spi_message *msg) +{ + cdns_spi_config_clock_mode(msg->spi); + return 0; +} + +/** + * cdns_transfer_one - Initiates the SPI transfer + * @master: Pointer to spi_master structure + * @spi: Pointer to the spi_device structure + * @transfer: Pointer to the spi_transfer structure which provides + * information about next transfer parameters + * + * This function fills the TX FIFO, starts the SPI transfer and + * returns a positive transfer count so that core will wait for completion. + * + * Return: Number of bytes transferred in the last transfer + */ +static int cdns_transfer_one(struct spi_master *master, + struct spi_device *spi, + struct spi_transfer *transfer) +{ + struct cdns_spi *xspi = spi_master_get_devdata(master); + + xspi->txbuf = transfer->tx_buf; + xspi->rxbuf = transfer->rx_buf; + xspi->tx_bytes = transfer->len; + xspi->rx_bytes = transfer->len; + + cdns_spi_setup_transfer(spi, transfer); + + cdns_spi_fill_tx_fifo(xspi); + + cdns_spi_write(xspi, CDNS_SPI_IER_OFFSET, + CDNS_SPI_IXR_DEFAULT_MASK); + return transfer->len; +} + +/** + * cdns_prepare_transfer_hardware - Prepares hardware for transfer. + * @master: Pointer to the spi_master structure which provides + * information about the controller. + * + * This function enables SPI master controller. + * + * Return: 0 always + */ +static int cdns_prepare_transfer_hardware(struct spi_master *master) +{ + struct cdns_spi *xspi = spi_master_get_devdata(master); + + cdns_spi_write(xspi, CDNS_SPI_ER_OFFSET, + CDNS_SPI_ER_ENABLE_MASK); + + return 0; +} + +/** + * cdns_unprepare_transfer_hardware - Relaxes hardware after transfer + * @master: Pointer to the spi_master structure which provides + * information about the controller. + * + * This function disables the SPI master controller. + * + * Return: 0 always + */ +static int cdns_unprepare_transfer_hardware(struct spi_master *master) +{ + struct cdns_spi *xspi = spi_master_get_devdata(master); + + cdns_spi_write(xspi, CDNS_SPI_ER_OFFSET, + CDNS_SPI_ER_DISABLE_MASK); + + return 0; +} + +/** + * cdns_spi_probe - Probe method for the SPI driver + * @pdev: Pointer to the platform_device structure + * + * This function initializes the driver data structures and the hardware. + * + * Return: 0 on success and error value on error + */ +static int cdns_spi_probe(struct platform_device *pdev) +{ + int ret = 0, irq; + struct spi_master *master; + struct cdns_spi *xspi; + struct resource *res; + u32 num_cs; + + master = spi_alloc_master(&pdev->dev, sizeof(*xspi)); + if (master == NULL) + return -ENOMEM; + + xspi = spi_master_get_devdata(master); + master->dev.of_node = pdev->dev.of_node; + platform_set_drvdata(pdev, master); + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + xspi->regs = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(xspi->regs)) { + ret = PTR_ERR(xspi->regs); + goto remove_master; + } + + xspi->pclk = devm_clk_get(&pdev->dev, "pclk"); + if (IS_ERR(xspi->pclk)) { + dev_err(&pdev->dev, "pclk clock not found.\n"); + ret = PTR_ERR(xspi->pclk); + goto remove_master; + } + + xspi->ref_clk = devm_clk_get(&pdev->dev, "ref_clk"); + if (IS_ERR(xspi->ref_clk)) { + dev_err(&pdev->dev, "ref_clk clock not found.\n"); + ret = PTR_ERR(xspi->ref_clk); + goto remove_master; + } + + ret = clk_prepare_enable(xspi->pclk); + if (ret) { + dev_err(&pdev->dev, "Unable to enable APB clock.\n"); + goto remove_master; + } + + ret = clk_prepare_enable(xspi->ref_clk); + if (ret) { + dev_err(&pdev->dev, "Unable to enable device clock.\n"); + goto clk_dis_apb; + } + + ret = of_property_read_u32(pdev->dev.of_node, "num-cs", &num_cs); + if (ret < 0) + master->num_chipselect = CDNS_SPI_DEFAULT_NUM_CS; + else + master->num_chipselect = num_cs; + + ret = of_property_read_u32(pdev->dev.of_node, "is-decoded-cs", + &xspi->is_decoded_cs); + if (ret < 0) + xspi->is_decoded_cs = 0; + + /* SPI controller initializations */ + cdns_spi_init_hw(xspi); + + irq = platform_get_irq(pdev, 0); + if (irq <= 0) { + ret = -ENXIO; + dev_err(&pdev->dev, "irq number is invalid\n"); + goto remove_master; + } + + ret = devm_request_irq(&pdev->dev, irq, cdns_spi_irq, + 0, pdev->name, master); + if (ret != 0) { + ret = -ENXIO; + dev_err(&pdev->dev, "request_irq failed\n"); + goto remove_master; + } + + master->prepare_transfer_hardware = cdns_prepare_transfer_hardware; + master->prepare_message = cdns_prepare_message; + master->transfer_one = cdns_transfer_one; + master->unprepare_transfer_hardware = cdns_unprepare_transfer_hardware; + master->set_cs = cdns_spi_chipselect; + master->mode_bits = SPI_CPOL | SPI_CPHA; + + /* Set to default valid value */ + master->max_speed_hz = clk_get_rate(xspi->ref_clk) / 4; + xspi->speed_hz = master->max_speed_hz; + + master->bits_per_word_mask = SPI_BPW_MASK(8); + + ret = spi_register_master(master); + if (ret) { + dev_err(&pdev->dev, "spi_register_master failed\n"); + goto clk_dis_all; + } + + return ret; + +clk_dis_all: + clk_disable_unprepare(xspi->ref_clk); +clk_dis_apb: + clk_disable_unprepare(xspi->pclk); +remove_master: + spi_master_put(master); + return ret; +} + +/** + * cdns_spi_remove - Remove method for the SPI driver + * @pdev: Pointer to the platform_device structure + * + * This function is called if a device is physically removed from the system or + * if the driver module is being unloaded. It frees all resources allocated to + * the device. + * + * Return: 0 on success and error value on error + */ +static int cdns_spi_remove(struct platform_device *pdev) +{ + struct spi_master *master = platform_get_drvdata(pdev); + struct cdns_spi *xspi = spi_master_get_devdata(master); + + cdns_spi_write(xspi, CDNS_SPI_ER_OFFSET, + CDNS_SPI_ER_DISABLE_MASK); + + clk_disable_unprepare(xspi->ref_clk); + clk_disable_unprepare(xspi->pclk); + + spi_unregister_master(master); + + return 0; +} + +/** + * cdns_spi_suspend - Suspend method for the SPI driver + * @dev: Address of the platform_device structure + * + * This function disables the SPI controller and + * changes the driver state to "suspend" + * + * Return: Always 0 + */ +static int __maybe_unused cdns_spi_suspend(struct device *dev) +{ + struct platform_device *pdev = container_of(dev, + struct platform_device, dev); + struct spi_master *master = platform_get_drvdata(pdev); + struct cdns_spi *xspi = spi_master_get_devdata(master); + + spi_master_suspend(master); + + clk_disable_unprepare(xspi->ref_clk); + + clk_disable_unprepare(xspi->pclk); + + return 0; +} + +/** + * cdns_spi_resume - Resume method for the SPI driver + * @dev: Address of the platform_device structure + * + * This function changes the driver state to "ready" + * + * Return: 0 on success and error value on error + */ +static int __maybe_unused cdns_spi_resume(struct device *dev) +{ + struct platform_device *pdev = container_of(dev, + struct platform_device, dev); + struct spi_master *master = platform_get_drvdata(pdev); + struct cdns_spi *xspi = spi_master_get_devdata(master); + int ret = 0; + + ret = clk_prepare_enable(xspi->pclk); + if (ret) { + dev_err(dev, "Cannot enable APB clock.\n"); + return ret; + } + + ret = clk_prepare_enable(xspi->ref_clk); + if (ret) { + dev_err(dev, "Cannot enable device clock.\n"); + clk_disable(xspi->pclk); + return ret; + } + spi_master_resume(master); + + return 0; +} + +static SIMPLE_DEV_PM_OPS(cdns_spi_dev_pm_ops, cdns_spi_suspend, + cdns_spi_resume); + +static const struct of_device_id cdns_spi_of_match[] = { + { .compatible = "xlnx,zynq-spi-r1p6" }, + { .compatible = "cdns,spi-r1p6" }, + { /* end of table */ } +}; +MODULE_DEVICE_TABLE(of, cdns_spi_of_match); + +/* cdns_spi_driver - This structure defines the SPI subsystem platform driver */ +static struct platform_driver cdns_spi_driver = { + .probe = cdns_spi_probe, + .remove = cdns_spi_remove, + .driver = { + .name = CDNS_SPI_NAME, + .of_match_table = cdns_spi_of_match, + .pm = &cdns_spi_dev_pm_ops, + }, +}; + +module_platform_driver(cdns_spi_driver); + +MODULE_AUTHOR("Xilinx, Inc."); +MODULE_DESCRIPTION("Cadence SPI driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/spi/spi-clps711x.c b/drivers/spi/spi-clps711x.c new file mode 100644 index 000000000..8c30de031 --- /dev/null +++ b/drivers/spi/spi-clps711x.c @@ -0,0 +1,214 @@ +/* + * CLPS711X SPI bus driver + * + * Copyright (C) 2012-2014 Alexander Shiyan <shc_work@mail.ru> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + */ + +#include <linux/io.h> +#include <linux/clk.h> +#include <linux/gpio.h> +#include <linux/delay.h> +#include <linux/module.h> +#include <linux/interrupt.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> +#include <linux/mfd/syscon.h> +#include <linux/mfd/syscon/clps711x.h> +#include <linux/spi/spi.h> +#include <linux/platform_data/spi-clps711x.h> + +#define DRIVER_NAME "spi-clps711x" + +#define SYNCIO_FRMLEN(x) ((x) << 8) +#define SYNCIO_TXFRMEN (1 << 14) + +struct spi_clps711x_data { + void __iomem *syncio; + struct regmap *syscon; + struct clk *spi_clk; + + u8 *tx_buf; + u8 *rx_buf; + unsigned int bpw; + int len; +}; + +static int spi_clps711x_setup(struct spi_device *spi) +{ + /* We are expect that SPI-device is not selected */ + gpio_direction_output(spi->cs_gpio, !(spi->mode & SPI_CS_HIGH)); + + return 0; +} + +static int spi_clps711x_prepare_message(struct spi_master *master, + struct spi_message *msg) +{ + struct spi_clps711x_data *hw = spi_master_get_devdata(master); + struct spi_device *spi = msg->spi; + + /* Setup mode for transfer */ + return regmap_update_bits(hw->syscon, SYSCON_OFFSET, SYSCON3_ADCCKNSEN, + (spi->mode & SPI_CPHA) ? + SYSCON3_ADCCKNSEN : 0); +} + +static int spi_clps711x_transfer_one(struct spi_master *master, + struct spi_device *spi, + struct spi_transfer *xfer) +{ + struct spi_clps711x_data *hw = spi_master_get_devdata(master); + u8 data; + + clk_set_rate(hw->spi_clk, xfer->speed_hz ? : spi->max_speed_hz); + + hw->len = xfer->len; + hw->bpw = xfer->bits_per_word; + hw->tx_buf = (u8 *)xfer->tx_buf; + hw->rx_buf = (u8 *)xfer->rx_buf; + + /* Initiate transfer */ + data = hw->tx_buf ? *hw->tx_buf++ : 0; + writel(data | SYNCIO_FRMLEN(hw->bpw) | SYNCIO_TXFRMEN, hw->syncio); + + return 1; +} + +static irqreturn_t spi_clps711x_isr(int irq, void *dev_id) +{ + struct spi_master *master = dev_id; + struct spi_clps711x_data *hw = spi_master_get_devdata(master); + u8 data; + + /* Handle RX */ + data = readb(hw->syncio); + if (hw->rx_buf) + *hw->rx_buf++ = data; + + /* Handle TX */ + if (--hw->len > 0) { + data = hw->tx_buf ? *hw->tx_buf++ : 0; + writel(data | SYNCIO_FRMLEN(hw->bpw) | SYNCIO_TXFRMEN, + hw->syncio); + } else + spi_finalize_current_transfer(master); + + return IRQ_HANDLED; +} + +static int spi_clps711x_probe(struct platform_device *pdev) +{ + struct spi_clps711x_data *hw; + struct spi_clps711x_pdata *pdata = dev_get_platdata(&pdev->dev); + struct spi_master *master; + struct resource *res; + int i, irq, ret; + + if (!pdata) { + dev_err(&pdev->dev, "No platform data supplied\n"); + return -EINVAL; + } + + if (pdata->num_chipselect < 1) { + dev_err(&pdev->dev, "At least one CS must be defined\n"); + return -EINVAL; + } + + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; + + master = spi_alloc_master(&pdev->dev, sizeof(*hw)); + if (!master) + return -ENOMEM; + + master->cs_gpios = devm_kzalloc(&pdev->dev, sizeof(int) * + pdata->num_chipselect, GFP_KERNEL); + if (!master->cs_gpios) { + ret = -ENOMEM; + goto err_out; + } + + master->bus_num = pdev->id; + master->mode_bits = SPI_CPHA | SPI_CS_HIGH; + master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 8); + master->num_chipselect = pdata->num_chipselect; + master->setup = spi_clps711x_setup; + master->prepare_message = spi_clps711x_prepare_message; + master->transfer_one = spi_clps711x_transfer_one; + + hw = spi_master_get_devdata(master); + + for (i = 0; i < master->num_chipselect; i++) { + master->cs_gpios[i] = pdata->chipselect[i]; + ret = devm_gpio_request(&pdev->dev, master->cs_gpios[i], + DRIVER_NAME); + if (ret) { + dev_err(&pdev->dev, "Can't get CS GPIO %i\n", i); + goto err_out; + } + } + + hw->spi_clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(hw->spi_clk)) { + ret = PTR_ERR(hw->spi_clk); + goto err_out; + } + + hw->syscon = syscon_regmap_lookup_by_pdevname("syscon.3"); + if (IS_ERR(hw->syscon)) { + ret = PTR_ERR(hw->syscon); + goto err_out; + } + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + hw->syncio = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(hw->syncio)) { + ret = PTR_ERR(hw->syncio); + goto err_out; + } + + /* Disable extended mode due hardware problems */ + regmap_update_bits(hw->syscon, SYSCON_OFFSET, SYSCON3_ADCCON, 0); + + /* Clear possible pending interrupt */ + readl(hw->syncio); + + ret = devm_request_irq(&pdev->dev, irq, spi_clps711x_isr, 0, + dev_name(&pdev->dev), master); + if (ret) + goto err_out; + + ret = devm_spi_register_master(&pdev->dev, master); + if (!ret) { + dev_info(&pdev->dev, + "SPI bus driver initialized. Master clock %u Hz\n", + master->max_speed_hz); + return 0; + } + + dev_err(&pdev->dev, "Failed to register master\n"); + +err_out: + spi_master_put(master); + + return ret; +} + +static struct platform_driver clps711x_spi_driver = { + .driver = { + .name = DRIVER_NAME, + }, + .probe = spi_clps711x_probe, +}; +module_platform_driver(clps711x_spi_driver); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Alexander Shiyan <shc_work@mail.ru>"); +MODULE_DESCRIPTION("CLPS711X SPI bus driver"); +MODULE_ALIAS("platform:" DRIVER_NAME); diff --git a/drivers/spi/spi-coldfire-qspi.c b/drivers/spi/spi-coldfire-qspi.c new file mode 100644 index 000000000..688956ff5 --- /dev/null +++ b/drivers/spi/spi-coldfire-qspi.c @@ -0,0 +1,529 @@ +/* + * Freescale/Motorola Coldfire Queued SPI driver + * + * Copyright 2010 Steven King <sfking@fdwdc.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. +*/ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/interrupt.h> +#include <linux/errno.h> +#include <linux/platform_device.h> +#include <linux/sched.h> +#include <linux/delay.h> +#include <linux/io.h> +#include <linux/clk.h> +#include <linux/err.h> +#include <linux/spi/spi.h> +#include <linux/pm_runtime.h> + +#include <asm/coldfire.h> +#include <asm/mcfsim.h> +#include <asm/mcfqspi.h> + +#define DRIVER_NAME "mcfqspi" + +#define MCFQSPI_BUSCLK (MCF_BUSCLK / 2) + +#define MCFQSPI_QMR 0x00 +#define MCFQSPI_QMR_MSTR 0x8000 +#define MCFQSPI_QMR_CPOL 0x0200 +#define MCFQSPI_QMR_CPHA 0x0100 +#define MCFQSPI_QDLYR 0x04 +#define MCFQSPI_QDLYR_SPE 0x8000 +#define MCFQSPI_QWR 0x08 +#define MCFQSPI_QWR_HALT 0x8000 +#define MCFQSPI_QWR_WREN 0x4000 +#define MCFQSPI_QWR_CSIV 0x1000 +#define MCFQSPI_QIR 0x0C +#define MCFQSPI_QIR_WCEFB 0x8000 +#define MCFQSPI_QIR_ABRTB 0x4000 +#define MCFQSPI_QIR_ABRTL 0x1000 +#define MCFQSPI_QIR_WCEFE 0x0800 +#define MCFQSPI_QIR_ABRTE 0x0400 +#define MCFQSPI_QIR_SPIFE 0x0100 +#define MCFQSPI_QIR_WCEF 0x0008 +#define MCFQSPI_QIR_ABRT 0x0004 +#define MCFQSPI_QIR_SPIF 0x0001 +#define MCFQSPI_QAR 0x010 +#define MCFQSPI_QAR_TXBUF 0x00 +#define MCFQSPI_QAR_RXBUF 0x10 +#define MCFQSPI_QAR_CMDBUF 0x20 +#define MCFQSPI_QDR 0x014 +#define MCFQSPI_QCR 0x014 +#define MCFQSPI_QCR_CONT 0x8000 +#define MCFQSPI_QCR_BITSE 0x4000 +#define MCFQSPI_QCR_DT 0x2000 + +struct mcfqspi { + void __iomem *iobase; + int irq; + struct clk *clk; + struct mcfqspi_cs_control *cs_control; + + wait_queue_head_t waitq; +}; + +static void mcfqspi_wr_qmr(struct mcfqspi *mcfqspi, u16 val) +{ + writew(val, mcfqspi->iobase + MCFQSPI_QMR); +} + +static void mcfqspi_wr_qdlyr(struct mcfqspi *mcfqspi, u16 val) +{ + writew(val, mcfqspi->iobase + MCFQSPI_QDLYR); +} + +static u16 mcfqspi_rd_qdlyr(struct mcfqspi *mcfqspi) +{ + return readw(mcfqspi->iobase + MCFQSPI_QDLYR); +} + +static void mcfqspi_wr_qwr(struct mcfqspi *mcfqspi, u16 val) +{ + writew(val, mcfqspi->iobase + MCFQSPI_QWR); +} + +static void mcfqspi_wr_qir(struct mcfqspi *mcfqspi, u16 val) +{ + writew(val, mcfqspi->iobase + MCFQSPI_QIR); +} + +static void mcfqspi_wr_qar(struct mcfqspi *mcfqspi, u16 val) +{ + writew(val, mcfqspi->iobase + MCFQSPI_QAR); +} + +static void mcfqspi_wr_qdr(struct mcfqspi *mcfqspi, u16 val) +{ + writew(val, mcfqspi->iobase + MCFQSPI_QDR); +} + +static u16 mcfqspi_rd_qdr(struct mcfqspi *mcfqspi) +{ + return readw(mcfqspi->iobase + MCFQSPI_QDR); +} + +static void mcfqspi_cs_select(struct mcfqspi *mcfqspi, u8 chip_select, + bool cs_high) +{ + mcfqspi->cs_control->select(mcfqspi->cs_control, chip_select, cs_high); +} + +static void mcfqspi_cs_deselect(struct mcfqspi *mcfqspi, u8 chip_select, + bool cs_high) +{ + mcfqspi->cs_control->deselect(mcfqspi->cs_control, chip_select, cs_high); +} + +static int mcfqspi_cs_setup(struct mcfqspi *mcfqspi) +{ + return (mcfqspi->cs_control->setup) ? + mcfqspi->cs_control->setup(mcfqspi->cs_control) : 0; +} + +static void mcfqspi_cs_teardown(struct mcfqspi *mcfqspi) +{ + if (mcfqspi->cs_control->teardown) + mcfqspi->cs_control->teardown(mcfqspi->cs_control); +} + +static u8 mcfqspi_qmr_baud(u32 speed_hz) +{ + return clamp((MCFQSPI_BUSCLK + speed_hz - 1) / speed_hz, 2u, 255u); +} + +static bool mcfqspi_qdlyr_spe(struct mcfqspi *mcfqspi) +{ + return mcfqspi_rd_qdlyr(mcfqspi) & MCFQSPI_QDLYR_SPE; +} + +static irqreturn_t mcfqspi_irq_handler(int this_irq, void *dev_id) +{ + struct mcfqspi *mcfqspi = dev_id; + + /* clear interrupt */ + mcfqspi_wr_qir(mcfqspi, MCFQSPI_QIR_SPIFE | MCFQSPI_QIR_SPIF); + wake_up(&mcfqspi->waitq); + + return IRQ_HANDLED; +} + +static void mcfqspi_transfer_msg8(struct mcfqspi *mcfqspi, unsigned count, + const u8 *txbuf, u8 *rxbuf) +{ + unsigned i, n, offset = 0; + + n = min(count, 16u); + + mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_CMDBUF); + for (i = 0; i < n; ++i) + mcfqspi_wr_qdr(mcfqspi, MCFQSPI_QCR_BITSE); + + mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_TXBUF); + if (txbuf) + for (i = 0; i < n; ++i) + mcfqspi_wr_qdr(mcfqspi, *txbuf++); + else + for (i = 0; i < count; ++i) + mcfqspi_wr_qdr(mcfqspi, 0); + + count -= n; + if (count) { + u16 qwr = 0xf08; + mcfqspi_wr_qwr(mcfqspi, 0x700); + mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE); + + do { + wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi)); + mcfqspi_wr_qwr(mcfqspi, qwr); + mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE); + if (rxbuf) { + mcfqspi_wr_qar(mcfqspi, + MCFQSPI_QAR_RXBUF + offset); + for (i = 0; i < 8; ++i) + *rxbuf++ = mcfqspi_rd_qdr(mcfqspi); + } + n = min(count, 8u); + if (txbuf) { + mcfqspi_wr_qar(mcfqspi, + MCFQSPI_QAR_TXBUF + offset); + for (i = 0; i < n; ++i) + mcfqspi_wr_qdr(mcfqspi, *txbuf++); + } + qwr = (offset ? 0x808 : 0) + ((n - 1) << 8); + offset ^= 8; + count -= n; + } while (count); + wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi)); + mcfqspi_wr_qwr(mcfqspi, qwr); + mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE); + if (rxbuf) { + mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_RXBUF + offset); + for (i = 0; i < 8; ++i) + *rxbuf++ = mcfqspi_rd_qdr(mcfqspi); + offset ^= 8; + } + } else { + mcfqspi_wr_qwr(mcfqspi, (n - 1) << 8); + mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE); + } + wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi)); + if (rxbuf) { + mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_RXBUF + offset); + for (i = 0; i < n; ++i) + *rxbuf++ = mcfqspi_rd_qdr(mcfqspi); + } +} + +static void mcfqspi_transfer_msg16(struct mcfqspi *mcfqspi, unsigned count, + const u16 *txbuf, u16 *rxbuf) +{ + unsigned i, n, offset = 0; + + n = min(count, 16u); + + mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_CMDBUF); + for (i = 0; i < n; ++i) + mcfqspi_wr_qdr(mcfqspi, MCFQSPI_QCR_BITSE); + + mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_TXBUF); + if (txbuf) + for (i = 0; i < n; ++i) + mcfqspi_wr_qdr(mcfqspi, *txbuf++); + else + for (i = 0; i < count; ++i) + mcfqspi_wr_qdr(mcfqspi, 0); + + count -= n; + if (count) { + u16 qwr = 0xf08; + mcfqspi_wr_qwr(mcfqspi, 0x700); + mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE); + + do { + wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi)); + mcfqspi_wr_qwr(mcfqspi, qwr); + mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE); + if (rxbuf) { + mcfqspi_wr_qar(mcfqspi, + MCFQSPI_QAR_RXBUF + offset); + for (i = 0; i < 8; ++i) + *rxbuf++ = mcfqspi_rd_qdr(mcfqspi); + } + n = min(count, 8u); + if (txbuf) { + mcfqspi_wr_qar(mcfqspi, + MCFQSPI_QAR_TXBUF + offset); + for (i = 0; i < n; ++i) + mcfqspi_wr_qdr(mcfqspi, *txbuf++); + } + qwr = (offset ? 0x808 : 0x000) + ((n - 1) << 8); + offset ^= 8; + count -= n; + } while (count); + wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi)); + mcfqspi_wr_qwr(mcfqspi, qwr); + mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE); + if (rxbuf) { + mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_RXBUF + offset); + for (i = 0; i < 8; ++i) + *rxbuf++ = mcfqspi_rd_qdr(mcfqspi); + offset ^= 8; + } + } else { + mcfqspi_wr_qwr(mcfqspi, (n - 1) << 8); + mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE); + } + wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi)); + if (rxbuf) { + mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_RXBUF + offset); + for (i = 0; i < n; ++i) + *rxbuf++ = mcfqspi_rd_qdr(mcfqspi); + } +} + +static void mcfqspi_set_cs(struct spi_device *spi, bool enable) +{ + struct mcfqspi *mcfqspi = spi_master_get_devdata(spi->master); + bool cs_high = spi->mode & SPI_CS_HIGH; + + if (enable) + mcfqspi_cs_select(mcfqspi, spi->chip_select, cs_high); + else + mcfqspi_cs_deselect(mcfqspi, spi->chip_select, cs_high); +} + +static int mcfqspi_transfer_one(struct spi_master *master, + struct spi_device *spi, + struct spi_transfer *t) +{ + struct mcfqspi *mcfqspi = spi_master_get_devdata(master); + u16 qmr = MCFQSPI_QMR_MSTR; + + qmr |= t->bits_per_word << 10; + if (spi->mode & SPI_CPHA) + qmr |= MCFQSPI_QMR_CPHA; + if (spi->mode & SPI_CPOL) + qmr |= MCFQSPI_QMR_CPOL; + qmr |= mcfqspi_qmr_baud(t->speed_hz); + mcfqspi_wr_qmr(mcfqspi, qmr); + + mcfqspi_wr_qir(mcfqspi, MCFQSPI_QIR_SPIFE); + if (t->bits_per_word == 8) + mcfqspi_transfer_msg8(mcfqspi, t->len, t->tx_buf, t->rx_buf); + else + mcfqspi_transfer_msg16(mcfqspi, t->len / 2, t->tx_buf, + t->rx_buf); + mcfqspi_wr_qir(mcfqspi, 0); + + return 0; +} + +static int mcfqspi_setup(struct spi_device *spi) +{ + mcfqspi_cs_deselect(spi_master_get_devdata(spi->master), + spi->chip_select, spi->mode & SPI_CS_HIGH); + + dev_dbg(&spi->dev, + "bits per word %d, chip select %d, speed %d KHz\n", + spi->bits_per_word, spi->chip_select, + (MCFQSPI_BUSCLK / mcfqspi_qmr_baud(spi->max_speed_hz)) + / 1000); + + return 0; +} + +static int mcfqspi_probe(struct platform_device *pdev) +{ + struct spi_master *master; + struct mcfqspi *mcfqspi; + struct resource *res; + struct mcfqspi_platform_data *pdata; + int status; + + pdata = dev_get_platdata(&pdev->dev); + if (!pdata) { + dev_dbg(&pdev->dev, "platform data is missing\n"); + return -ENOENT; + } + + if (!pdata->cs_control) { + dev_dbg(&pdev->dev, "pdata->cs_control is NULL\n"); + return -EINVAL; + } + + master = spi_alloc_master(&pdev->dev, sizeof(*mcfqspi)); + if (master == NULL) { + dev_dbg(&pdev->dev, "spi_alloc_master failed\n"); + return -ENOMEM; + } + + mcfqspi = spi_master_get_devdata(master); + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + mcfqspi->iobase = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(mcfqspi->iobase)) { + status = PTR_ERR(mcfqspi->iobase); + goto fail0; + } + + mcfqspi->irq = platform_get_irq(pdev, 0); + if (mcfqspi->irq < 0) { + dev_dbg(&pdev->dev, "platform_get_irq failed\n"); + status = -ENXIO; + goto fail0; + } + + status = devm_request_irq(&pdev->dev, mcfqspi->irq, mcfqspi_irq_handler, + 0, pdev->name, mcfqspi); + if (status) { + dev_dbg(&pdev->dev, "request_irq failed\n"); + goto fail0; + } + + mcfqspi->clk = devm_clk_get(&pdev->dev, "qspi_clk"); + if (IS_ERR(mcfqspi->clk)) { + dev_dbg(&pdev->dev, "clk_get failed\n"); + status = PTR_ERR(mcfqspi->clk); + goto fail0; + } + clk_enable(mcfqspi->clk); + + master->bus_num = pdata->bus_num; + master->num_chipselect = pdata->num_chipselect; + + mcfqspi->cs_control = pdata->cs_control; + status = mcfqspi_cs_setup(mcfqspi); + if (status) { + dev_dbg(&pdev->dev, "error initializing cs_control\n"); + goto fail1; + } + + init_waitqueue_head(&mcfqspi->waitq); + + master->mode_bits = SPI_CS_HIGH | SPI_CPOL | SPI_CPHA; + master->bits_per_word_mask = SPI_BPW_RANGE_MASK(8, 16); + master->setup = mcfqspi_setup; + master->set_cs = mcfqspi_set_cs; + master->transfer_one = mcfqspi_transfer_one; + master->auto_runtime_pm = true; + + platform_set_drvdata(pdev, master); + + status = devm_spi_register_master(&pdev->dev, master); + if (status) { + dev_dbg(&pdev->dev, "spi_register_master failed\n"); + goto fail2; + } + pm_runtime_enable(&pdev->dev); + + dev_info(&pdev->dev, "Coldfire QSPI bus driver\n"); + + return 0; + +fail2: + mcfqspi_cs_teardown(mcfqspi); +fail1: + clk_disable(mcfqspi->clk); +fail0: + spi_master_put(master); + + dev_dbg(&pdev->dev, "Coldfire QSPI probe failed\n"); + + return status; +} + +static int mcfqspi_remove(struct platform_device *pdev) +{ + struct spi_master *master = platform_get_drvdata(pdev); + struct mcfqspi *mcfqspi = spi_master_get_devdata(master); + + pm_runtime_disable(&pdev->dev); + /* disable the hardware (set the baud rate to 0) */ + mcfqspi_wr_qmr(mcfqspi, MCFQSPI_QMR_MSTR); + + mcfqspi_cs_teardown(mcfqspi); + clk_disable(mcfqspi->clk); + + return 0; +} + +#ifdef CONFIG_PM_SLEEP +static int mcfqspi_suspend(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct mcfqspi *mcfqspi = spi_master_get_devdata(master); + int ret; + + ret = spi_master_suspend(master); + if (ret) + return ret; + + clk_disable(mcfqspi->clk); + + return 0; +} + +static int mcfqspi_resume(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct mcfqspi *mcfqspi = spi_master_get_devdata(master); + + clk_enable(mcfqspi->clk); + + return spi_master_resume(master); +} +#endif + +#ifdef CONFIG_PM +static int mcfqspi_runtime_suspend(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct mcfqspi *mcfqspi = spi_master_get_devdata(master); + + clk_disable(mcfqspi->clk); + + return 0; +} + +static int mcfqspi_runtime_resume(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct mcfqspi *mcfqspi = spi_master_get_devdata(master); + + clk_enable(mcfqspi->clk); + + return 0; +} +#endif + +static const struct dev_pm_ops mcfqspi_pm = { + SET_SYSTEM_SLEEP_PM_OPS(mcfqspi_suspend, mcfqspi_resume) + SET_RUNTIME_PM_OPS(mcfqspi_runtime_suspend, mcfqspi_runtime_resume, + NULL) +}; + +static struct platform_driver mcfqspi_driver = { + .driver.name = DRIVER_NAME, + .driver.owner = THIS_MODULE, + .driver.pm = &mcfqspi_pm, + .probe = mcfqspi_probe, + .remove = mcfqspi_remove, +}; +module_platform_driver(mcfqspi_driver); + +MODULE_AUTHOR("Steven King <sfking@fdwdc.com>"); +MODULE_DESCRIPTION("Coldfire QSPI Controller Driver"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:" DRIVER_NAME); diff --git a/drivers/spi/spi-davinci.c b/drivers/spi/spi-davinci.c new file mode 100644 index 000000000..5e991065f --- /dev/null +++ b/drivers/spi/spi-davinci.c @@ -0,0 +1,1126 @@ +/* + * Copyright (C) 2009 Texas Instruments. + * Copyright (C) 2010 EF Johnson Technologies + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/gpio.h> +#include <linux/module.h> +#include <linux/delay.h> +#include <linux/platform_device.h> +#include <linux/err.h> +#include <linux/clk.h> +#include <linux/dmaengine.h> +#include <linux/dma-mapping.h> +#include <linux/edma.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/of_gpio.h> +#include <linux/spi/spi.h> +#include <linux/spi/spi_bitbang.h> +#include <linux/slab.h> + +#include <linux/platform_data/spi-davinci.h> + +#define SPI_NO_RESOURCE ((resource_size_t)-1) + +#define CS_DEFAULT 0xFF + +#define SPIFMT_PHASE_MASK BIT(16) +#define SPIFMT_POLARITY_MASK BIT(17) +#define SPIFMT_DISTIMER_MASK BIT(18) +#define SPIFMT_SHIFTDIR_MASK BIT(20) +#define SPIFMT_WAITENA_MASK BIT(21) +#define SPIFMT_PARITYENA_MASK BIT(22) +#define SPIFMT_ODD_PARITY_MASK BIT(23) +#define SPIFMT_WDELAY_MASK 0x3f000000u +#define SPIFMT_WDELAY_SHIFT 24 +#define SPIFMT_PRESCALE_SHIFT 8 + +/* SPIPC0 */ +#define SPIPC0_DIFUN_MASK BIT(11) /* MISO */ +#define SPIPC0_DOFUN_MASK BIT(10) /* MOSI */ +#define SPIPC0_CLKFUN_MASK BIT(9) /* CLK */ +#define SPIPC0_SPIENA_MASK BIT(8) /* nREADY */ + +#define SPIINT_MASKALL 0x0101035F +#define SPIINT_MASKINT 0x0000015F +#define SPI_INTLVL_1 0x000001FF +#define SPI_INTLVL_0 0x00000000 + +/* SPIDAT1 (upper 16 bit defines) */ +#define SPIDAT1_CSHOLD_MASK BIT(12) +#define SPIDAT1_WDEL BIT(10) + +/* SPIGCR1 */ +#define SPIGCR1_CLKMOD_MASK BIT(1) +#define SPIGCR1_MASTER_MASK BIT(0) +#define SPIGCR1_POWERDOWN_MASK BIT(8) +#define SPIGCR1_LOOPBACK_MASK BIT(16) +#define SPIGCR1_SPIENA_MASK BIT(24) + +/* SPIBUF */ +#define SPIBUF_TXFULL_MASK BIT(29) +#define SPIBUF_RXEMPTY_MASK BIT(31) + +/* SPIDELAY */ +#define SPIDELAY_C2TDELAY_SHIFT 24 +#define SPIDELAY_C2TDELAY_MASK (0xFF << SPIDELAY_C2TDELAY_SHIFT) +#define SPIDELAY_T2CDELAY_SHIFT 16 +#define SPIDELAY_T2CDELAY_MASK (0xFF << SPIDELAY_T2CDELAY_SHIFT) +#define SPIDELAY_T2EDELAY_SHIFT 8 +#define SPIDELAY_T2EDELAY_MASK (0xFF << SPIDELAY_T2EDELAY_SHIFT) +#define SPIDELAY_C2EDELAY_SHIFT 0 +#define SPIDELAY_C2EDELAY_MASK 0xFF + +/* Error Masks */ +#define SPIFLG_DLEN_ERR_MASK BIT(0) +#define SPIFLG_TIMEOUT_MASK BIT(1) +#define SPIFLG_PARERR_MASK BIT(2) +#define SPIFLG_DESYNC_MASK BIT(3) +#define SPIFLG_BITERR_MASK BIT(4) +#define SPIFLG_OVRRUN_MASK BIT(6) +#define SPIFLG_BUF_INIT_ACTIVE_MASK BIT(24) +#define SPIFLG_ERROR_MASK (SPIFLG_DLEN_ERR_MASK \ + | SPIFLG_TIMEOUT_MASK | SPIFLG_PARERR_MASK \ + | SPIFLG_DESYNC_MASK | SPIFLG_BITERR_MASK \ + | SPIFLG_OVRRUN_MASK) + +#define SPIINT_DMA_REQ_EN BIT(16) + +/* SPI Controller registers */ +#define SPIGCR0 0x00 +#define SPIGCR1 0x04 +#define SPIINT 0x08 +#define SPILVL 0x0c +#define SPIFLG 0x10 +#define SPIPC0 0x14 +#define SPIDAT1 0x3c +#define SPIBUF 0x40 +#define SPIDELAY 0x48 +#define SPIDEF 0x4c +#define SPIFMT0 0x50 + +/* SPI Controller driver's private data. */ +struct davinci_spi { + struct spi_bitbang bitbang; + struct clk *clk; + + u8 version; + resource_size_t pbase; + void __iomem *base; + u32 irq; + struct completion done; + + const void *tx; + void *rx; + int rcount; + int wcount; + + struct dma_chan *dma_rx; + struct dma_chan *dma_tx; + int dma_rx_chnum; + int dma_tx_chnum; + + struct davinci_spi_platform_data pdata; + + void (*get_rx)(u32 rx_data, struct davinci_spi *); + u32 (*get_tx)(struct davinci_spi *); + + u8 *bytes_per_word; +}; + +static struct davinci_spi_config davinci_spi_default_cfg; + +static void davinci_spi_rx_buf_u8(u32 data, struct davinci_spi *dspi) +{ + if (dspi->rx) { + u8 *rx = dspi->rx; + *rx++ = (u8)data; + dspi->rx = rx; + } +} + +static void davinci_spi_rx_buf_u16(u32 data, struct davinci_spi *dspi) +{ + if (dspi->rx) { + u16 *rx = dspi->rx; + *rx++ = (u16)data; + dspi->rx = rx; + } +} + +static u32 davinci_spi_tx_buf_u8(struct davinci_spi *dspi) +{ + u32 data = 0; + + if (dspi->tx) { + const u8 *tx = dspi->tx; + + data = *tx++; + dspi->tx = tx; + } + return data; +} + +static u32 davinci_spi_tx_buf_u16(struct davinci_spi *dspi) +{ + u32 data = 0; + + if (dspi->tx) { + const u16 *tx = dspi->tx; + + data = *tx++; + dspi->tx = tx; + } + return data; +} + +static inline void set_io_bits(void __iomem *addr, u32 bits) +{ + u32 v = ioread32(addr); + + v |= bits; + iowrite32(v, addr); +} + +static inline void clear_io_bits(void __iomem *addr, u32 bits) +{ + u32 v = ioread32(addr); + + v &= ~bits; + iowrite32(v, addr); +} + +/* + * Interface to control the chip select signal + */ +static void davinci_spi_chipselect(struct spi_device *spi, int value) +{ + struct davinci_spi *dspi; + struct davinci_spi_platform_data *pdata; + struct davinci_spi_config *spicfg = spi->controller_data; + u8 chip_sel = spi->chip_select; + u16 spidat1 = CS_DEFAULT; + bool gpio_chipsel = false; + int gpio; + + dspi = spi_master_get_devdata(spi->master); + pdata = &dspi->pdata; + + if (spi->cs_gpio >= 0) { + /* SPI core parse and update master->cs_gpio */ + gpio_chipsel = true; + gpio = spi->cs_gpio; + } + + /* program delay transfers if tx_delay is non zero */ + if (spicfg->wdelay) + spidat1 |= SPIDAT1_WDEL; + + /* + * Board specific chip select logic decides the polarity and cs + * line for the controller + */ + if (gpio_chipsel) { + if (value == BITBANG_CS_ACTIVE) + gpio_set_value(gpio, spi->mode & SPI_CS_HIGH); + else + gpio_set_value(gpio, !(spi->mode & SPI_CS_HIGH)); + } else { + if (value == BITBANG_CS_ACTIVE) { + spidat1 |= SPIDAT1_CSHOLD_MASK; + spidat1 &= ~(0x1 << chip_sel); + } + } + + iowrite16(spidat1, dspi->base + SPIDAT1 + 2); +} + +/** + * davinci_spi_get_prescale - Calculates the correct prescale value + * @maxspeed_hz: the maximum rate the SPI clock can run at + * + * This function calculates the prescale value that generates a clock rate + * less than or equal to the specified maximum. + * + * Returns: calculated prescale - 1 for easy programming into SPI registers + * or negative error number if valid prescalar cannot be updated. + */ +static inline int davinci_spi_get_prescale(struct davinci_spi *dspi, + u32 max_speed_hz) +{ + int ret; + + ret = DIV_ROUND_UP(clk_get_rate(dspi->clk), max_speed_hz); + + if (ret < 3 || ret > 256) + return -EINVAL; + + return ret - 1; +} + +/** + * davinci_spi_setup_transfer - This functions will determine transfer method + * @spi: spi device on which data transfer to be done + * @t: spi transfer in which transfer info is filled + * + * This function determines data transfer method (8/16/32 bit transfer). + * It will also set the SPI Clock Control register according to + * SPI slave device freq. + */ +static int davinci_spi_setup_transfer(struct spi_device *spi, + struct spi_transfer *t) +{ + + struct davinci_spi *dspi; + struct davinci_spi_config *spicfg; + u8 bits_per_word = 0; + u32 hz = 0, spifmt = 0; + int prescale; + + dspi = spi_master_get_devdata(spi->master); + spicfg = spi->controller_data; + if (!spicfg) + spicfg = &davinci_spi_default_cfg; + + if (t) { + bits_per_word = t->bits_per_word; + hz = t->speed_hz; + } + + /* if bits_per_word is not set then set it default */ + if (!bits_per_word) + bits_per_word = spi->bits_per_word; + + /* + * Assign function pointer to appropriate transfer method + * 8bit, 16bit or 32bit transfer + */ + if (bits_per_word <= 8) { + dspi->get_rx = davinci_spi_rx_buf_u8; + dspi->get_tx = davinci_spi_tx_buf_u8; + dspi->bytes_per_word[spi->chip_select] = 1; + } else { + dspi->get_rx = davinci_spi_rx_buf_u16; + dspi->get_tx = davinci_spi_tx_buf_u16; + dspi->bytes_per_word[spi->chip_select] = 2; + } + + if (!hz) + hz = spi->max_speed_hz; + + /* Set up SPIFMTn register, unique to this chipselect. */ + + prescale = davinci_spi_get_prescale(dspi, hz); + if (prescale < 0) + return prescale; + + spifmt = (prescale << SPIFMT_PRESCALE_SHIFT) | (bits_per_word & 0x1f); + + if (spi->mode & SPI_LSB_FIRST) + spifmt |= SPIFMT_SHIFTDIR_MASK; + + if (spi->mode & SPI_CPOL) + spifmt |= SPIFMT_POLARITY_MASK; + + if (!(spi->mode & SPI_CPHA)) + spifmt |= SPIFMT_PHASE_MASK; + + /* + * Assume wdelay is used only on SPI peripherals that has this field + * in SPIFMTn register and when it's configured from board file or DT. + */ + if (spicfg->wdelay) + spifmt |= ((spicfg->wdelay << SPIFMT_WDELAY_SHIFT) + & SPIFMT_WDELAY_MASK); + + /* + * Version 1 hardware supports two basic SPI modes: + * - Standard SPI mode uses 4 pins, with chipselect + * - 3 pin SPI is a 4 pin variant without CS (SPI_NO_CS) + * (distinct from SPI_3WIRE, with just one data wire; + * or similar variants without MOSI or without MISO) + * + * Version 2 hardware supports an optional handshaking signal, + * so it can support two more modes: + * - 5 pin SPI variant is standard SPI plus SPI_READY + * - 4 pin with enable is (SPI_READY | SPI_NO_CS) + */ + + if (dspi->version == SPI_VERSION_2) { + + u32 delay = 0; + + if (spicfg->odd_parity) + spifmt |= SPIFMT_ODD_PARITY_MASK; + + if (spicfg->parity_enable) + spifmt |= SPIFMT_PARITYENA_MASK; + + if (spicfg->timer_disable) { + spifmt |= SPIFMT_DISTIMER_MASK; + } else { + delay |= (spicfg->c2tdelay << SPIDELAY_C2TDELAY_SHIFT) + & SPIDELAY_C2TDELAY_MASK; + delay |= (spicfg->t2cdelay << SPIDELAY_T2CDELAY_SHIFT) + & SPIDELAY_T2CDELAY_MASK; + } + + if (spi->mode & SPI_READY) { + spifmt |= SPIFMT_WAITENA_MASK; + delay |= (spicfg->t2edelay << SPIDELAY_T2EDELAY_SHIFT) + & SPIDELAY_T2EDELAY_MASK; + delay |= (spicfg->c2edelay << SPIDELAY_C2EDELAY_SHIFT) + & SPIDELAY_C2EDELAY_MASK; + } + + iowrite32(delay, dspi->base + SPIDELAY); + } + + iowrite32(spifmt, dspi->base + SPIFMT0); + + return 0; +} + +static int davinci_spi_of_setup(struct spi_device *spi) +{ + struct davinci_spi_config *spicfg = spi->controller_data; + struct device_node *np = spi->dev.of_node; + u32 prop; + + if (spicfg == NULL && np) { + spicfg = kzalloc(sizeof(*spicfg), GFP_KERNEL); + if (!spicfg) + return -ENOMEM; + *spicfg = davinci_spi_default_cfg; + /* override with dt configured values */ + if (!of_property_read_u32(np, "ti,spi-wdelay", &prop)) + spicfg->wdelay = (u8)prop; + spi->controller_data = spicfg; + } + + return 0; +} + +/** + * davinci_spi_setup - This functions will set default transfer method + * @spi: spi device on which data transfer to be done + * + * This functions sets the default transfer method. + */ +static int davinci_spi_setup(struct spi_device *spi) +{ + int retval = 0; + struct davinci_spi *dspi; + struct davinci_spi_platform_data *pdata; + struct spi_master *master = spi->master; + struct device_node *np = spi->dev.of_node; + bool internal_cs = true; + + dspi = spi_master_get_devdata(spi->master); + pdata = &dspi->pdata; + + if (!(spi->mode & SPI_NO_CS)) { + if (np && (master->cs_gpios != NULL) && (spi->cs_gpio >= 0)) { + retval = gpio_direction_output( + spi->cs_gpio, !(spi->mode & SPI_CS_HIGH)); + internal_cs = false; + } else if (pdata->chip_sel && + spi->chip_select < pdata->num_chipselect && + pdata->chip_sel[spi->chip_select] != SPI_INTERN_CS) { + spi->cs_gpio = pdata->chip_sel[spi->chip_select]; + retval = gpio_direction_output( + spi->cs_gpio, !(spi->mode & SPI_CS_HIGH)); + internal_cs = false; + } + + if (retval) { + dev_err(&spi->dev, "GPIO %d setup failed (%d)\n", + spi->cs_gpio, retval); + return retval; + } + + if (internal_cs) + set_io_bits(dspi->base + SPIPC0, 1 << spi->chip_select); + } + + if (spi->mode & SPI_READY) + set_io_bits(dspi->base + SPIPC0, SPIPC0_SPIENA_MASK); + + if (spi->mode & SPI_LOOP) + set_io_bits(dspi->base + SPIGCR1, SPIGCR1_LOOPBACK_MASK); + else + clear_io_bits(dspi->base + SPIGCR1, SPIGCR1_LOOPBACK_MASK); + + return davinci_spi_of_setup(spi); +} + +static void davinci_spi_cleanup(struct spi_device *spi) +{ + struct davinci_spi_config *spicfg = spi->controller_data; + + spi->controller_data = NULL; + if (spi->dev.of_node) + kfree(spicfg); +} + +static int davinci_spi_check_error(struct davinci_spi *dspi, int int_status) +{ + struct device *sdev = dspi->bitbang.master->dev.parent; + + if (int_status & SPIFLG_TIMEOUT_MASK) { + dev_dbg(sdev, "SPI Time-out Error\n"); + return -ETIMEDOUT; + } + if (int_status & SPIFLG_DESYNC_MASK) { + dev_dbg(sdev, "SPI Desynchronization Error\n"); + return -EIO; + } + if (int_status & SPIFLG_BITERR_MASK) { + dev_dbg(sdev, "SPI Bit error\n"); + return -EIO; + } + + if (dspi->version == SPI_VERSION_2) { + if (int_status & SPIFLG_DLEN_ERR_MASK) { + dev_dbg(sdev, "SPI Data Length Error\n"); + return -EIO; + } + if (int_status & SPIFLG_PARERR_MASK) { + dev_dbg(sdev, "SPI Parity Error\n"); + return -EIO; + } + if (int_status & SPIFLG_OVRRUN_MASK) { + dev_dbg(sdev, "SPI Data Overrun error\n"); + return -EIO; + } + if (int_status & SPIFLG_BUF_INIT_ACTIVE_MASK) { + dev_dbg(sdev, "SPI Buffer Init Active\n"); + return -EBUSY; + } + } + + return 0; +} + +/** + * davinci_spi_process_events - check for and handle any SPI controller events + * @dspi: the controller data + * + * This function will check the SPIFLG register and handle any events that are + * detected there + */ +static int davinci_spi_process_events(struct davinci_spi *dspi) +{ + u32 buf, status, errors = 0, spidat1; + + buf = ioread32(dspi->base + SPIBUF); + + if (dspi->rcount > 0 && !(buf & SPIBUF_RXEMPTY_MASK)) { + dspi->get_rx(buf & 0xFFFF, dspi); + dspi->rcount--; + } + + status = ioread32(dspi->base + SPIFLG); + + if (unlikely(status & SPIFLG_ERROR_MASK)) { + errors = status & SPIFLG_ERROR_MASK; + goto out; + } + + if (dspi->wcount > 0 && !(buf & SPIBUF_TXFULL_MASK)) { + spidat1 = ioread32(dspi->base + SPIDAT1); + dspi->wcount--; + spidat1 &= ~0xFFFF; + spidat1 |= 0xFFFF & dspi->get_tx(dspi); + iowrite32(spidat1, dspi->base + SPIDAT1); + } + +out: + return errors; +} + +static void davinci_spi_dma_rx_callback(void *data) +{ + struct davinci_spi *dspi = (struct davinci_spi *)data; + + dspi->rcount = 0; + + if (!dspi->wcount && !dspi->rcount) + complete(&dspi->done); +} + +static void davinci_spi_dma_tx_callback(void *data) +{ + struct davinci_spi *dspi = (struct davinci_spi *)data; + + dspi->wcount = 0; + + if (!dspi->wcount && !dspi->rcount) + complete(&dspi->done); +} + +/** + * davinci_spi_bufs - functions which will handle transfer data + * @spi: spi device on which data transfer to be done + * @t: spi transfer in which transfer info is filled + * + * This function will put data to be transferred into data register + * of SPI controller and then wait until the completion will be marked + * by the IRQ Handler. + */ +static int davinci_spi_bufs(struct spi_device *spi, struct spi_transfer *t) +{ + struct davinci_spi *dspi; + int data_type, ret = -ENOMEM; + u32 tx_data, spidat1; + u32 errors = 0; + struct davinci_spi_config *spicfg; + struct davinci_spi_platform_data *pdata; + unsigned uninitialized_var(rx_buf_count); + void *dummy_buf = NULL; + struct scatterlist sg_rx, sg_tx; + + dspi = spi_master_get_devdata(spi->master); + pdata = &dspi->pdata; + spicfg = (struct davinci_spi_config *)spi->controller_data; + if (!spicfg) + spicfg = &davinci_spi_default_cfg; + + /* convert len to words based on bits_per_word */ + data_type = dspi->bytes_per_word[spi->chip_select]; + + dspi->tx = t->tx_buf; + dspi->rx = t->rx_buf; + dspi->wcount = t->len / data_type; + dspi->rcount = dspi->wcount; + + spidat1 = ioread32(dspi->base + SPIDAT1); + + clear_io_bits(dspi->base + SPIGCR1, SPIGCR1_POWERDOWN_MASK); + set_io_bits(dspi->base + SPIGCR1, SPIGCR1_SPIENA_MASK); + + reinit_completion(&dspi->done); + + if (spicfg->io_type == SPI_IO_TYPE_INTR) + set_io_bits(dspi->base + SPIINT, SPIINT_MASKINT); + + if (spicfg->io_type != SPI_IO_TYPE_DMA) { + /* start the transfer */ + dspi->wcount--; + tx_data = dspi->get_tx(dspi); + spidat1 &= 0xFFFF0000; + spidat1 |= tx_data & 0xFFFF; + iowrite32(spidat1, dspi->base + SPIDAT1); + } else { + struct dma_slave_config dma_rx_conf = { + .direction = DMA_DEV_TO_MEM, + .src_addr = (unsigned long)dspi->pbase + SPIBUF, + .src_addr_width = data_type, + .src_maxburst = 1, + }; + struct dma_slave_config dma_tx_conf = { + .direction = DMA_MEM_TO_DEV, + .dst_addr = (unsigned long)dspi->pbase + SPIDAT1, + .dst_addr_width = data_type, + .dst_maxburst = 1, + }; + struct dma_async_tx_descriptor *rxdesc; + struct dma_async_tx_descriptor *txdesc; + void *buf; + + dummy_buf = kzalloc(t->len, GFP_KERNEL); + if (!dummy_buf) + goto err_alloc_dummy_buf; + + dmaengine_slave_config(dspi->dma_rx, &dma_rx_conf); + dmaengine_slave_config(dspi->dma_tx, &dma_tx_conf); + + sg_init_table(&sg_rx, 1); + if (!t->rx_buf) + buf = dummy_buf; + else + buf = t->rx_buf; + t->rx_dma = dma_map_single(&spi->dev, buf, + t->len, DMA_FROM_DEVICE); + if (!t->rx_dma) { + ret = -EFAULT; + goto err_rx_map; + } + sg_dma_address(&sg_rx) = t->rx_dma; + sg_dma_len(&sg_rx) = t->len; + + sg_init_table(&sg_tx, 1); + if (!t->tx_buf) + buf = dummy_buf; + else + buf = (void *)t->tx_buf; + t->tx_dma = dma_map_single(&spi->dev, buf, + t->len, DMA_TO_DEVICE); + if (!t->tx_dma) { + ret = -EFAULT; + goto err_tx_map; + } + sg_dma_address(&sg_tx) = t->tx_dma; + sg_dma_len(&sg_tx) = t->len; + + rxdesc = dmaengine_prep_slave_sg(dspi->dma_rx, + &sg_rx, 1, DMA_DEV_TO_MEM, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + if (!rxdesc) + goto err_desc; + + txdesc = dmaengine_prep_slave_sg(dspi->dma_tx, + &sg_tx, 1, DMA_MEM_TO_DEV, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + if (!txdesc) + goto err_desc; + + rxdesc->callback = davinci_spi_dma_rx_callback; + rxdesc->callback_param = (void *)dspi; + txdesc->callback = davinci_spi_dma_tx_callback; + txdesc->callback_param = (void *)dspi; + + if (pdata->cshold_bug) + iowrite16(spidat1 >> 16, dspi->base + SPIDAT1 + 2); + + dmaengine_submit(rxdesc); + dmaengine_submit(txdesc); + + dma_async_issue_pending(dspi->dma_rx); + dma_async_issue_pending(dspi->dma_tx); + + set_io_bits(dspi->base + SPIINT, SPIINT_DMA_REQ_EN); + } + + /* Wait for the transfer to complete */ + if (spicfg->io_type != SPI_IO_TYPE_POLL) { + wait_for_completion_interruptible(&(dspi->done)); + } else { + while (dspi->rcount > 0 || dspi->wcount > 0) { + errors = davinci_spi_process_events(dspi); + if (errors) + break; + cpu_relax(); + } + } + + clear_io_bits(dspi->base + SPIINT, SPIINT_MASKALL); + if (spicfg->io_type == SPI_IO_TYPE_DMA) { + clear_io_bits(dspi->base + SPIINT, SPIINT_DMA_REQ_EN); + + dma_unmap_single(&spi->dev, t->rx_dma, + t->len, DMA_FROM_DEVICE); + dma_unmap_single(&spi->dev, t->tx_dma, + t->len, DMA_TO_DEVICE); + kfree(dummy_buf); + } + + clear_io_bits(dspi->base + SPIGCR1, SPIGCR1_SPIENA_MASK); + set_io_bits(dspi->base + SPIGCR1, SPIGCR1_POWERDOWN_MASK); + + /* + * Check for bit error, desync error,parity error,timeout error and + * receive overflow errors + */ + if (errors) { + ret = davinci_spi_check_error(dspi, errors); + WARN(!ret, "%s: error reported but no error found!\n", + dev_name(&spi->dev)); + return ret; + } + + if (dspi->rcount != 0 || dspi->wcount != 0) { + dev_err(&spi->dev, "SPI data transfer error\n"); + return -EIO; + } + + return t->len; + +err_desc: + dma_unmap_single(&spi->dev, t->tx_dma, t->len, DMA_TO_DEVICE); +err_tx_map: + dma_unmap_single(&spi->dev, t->rx_dma, t->len, DMA_FROM_DEVICE); +err_rx_map: + kfree(dummy_buf); +err_alloc_dummy_buf: + return ret; +} + +/** + * dummy_thread_fn - dummy thread function + * @irq: IRQ number for this SPI Master + * @context_data: structure for SPI Master controller davinci_spi + * + * This is to satisfy the request_threaded_irq() API so that the irq + * handler is called in interrupt context. + */ +static irqreturn_t dummy_thread_fn(s32 irq, void *data) +{ + return IRQ_HANDLED; +} + +/** + * davinci_spi_irq - Interrupt handler for SPI Master Controller + * @irq: IRQ number for this SPI Master + * @context_data: structure for SPI Master controller davinci_spi + * + * ISR will determine that interrupt arrives either for READ or WRITE command. + * According to command it will do the appropriate action. It will check + * transfer length and if it is not zero then dispatch transfer command again. + * If transfer length is zero then it will indicate the COMPLETION so that + * davinci_spi_bufs function can go ahead. + */ +static irqreturn_t davinci_spi_irq(s32 irq, void *data) +{ + struct davinci_spi *dspi = data; + int status; + + status = davinci_spi_process_events(dspi); + if (unlikely(status != 0)) + clear_io_bits(dspi->base + SPIINT, SPIINT_MASKINT); + + if ((!dspi->rcount && !dspi->wcount) || status) + complete(&dspi->done); + + return IRQ_HANDLED; +} + +static int davinci_spi_request_dma(struct davinci_spi *dspi) +{ + dma_cap_mask_t mask; + struct device *sdev = dspi->bitbang.master->dev.parent; + int r; + + dma_cap_zero(mask); + dma_cap_set(DMA_SLAVE, mask); + + dspi->dma_rx = dma_request_channel(mask, edma_filter_fn, + &dspi->dma_rx_chnum); + if (!dspi->dma_rx) { + dev_err(sdev, "request RX DMA channel failed\n"); + r = -ENODEV; + goto rx_dma_failed; + } + + dspi->dma_tx = dma_request_channel(mask, edma_filter_fn, + &dspi->dma_tx_chnum); + if (!dspi->dma_tx) { + dev_err(sdev, "request TX DMA channel failed\n"); + r = -ENODEV; + goto tx_dma_failed; + } + + return 0; + +tx_dma_failed: + dma_release_channel(dspi->dma_rx); +rx_dma_failed: + return r; +} + +#if defined(CONFIG_OF) +static const struct of_device_id davinci_spi_of_match[] = { + { + .compatible = "ti,dm6441-spi", + }, + { + .compatible = "ti,da830-spi", + .data = (void *)SPI_VERSION_2, + }, + { }, +}; +MODULE_DEVICE_TABLE(of, davinci_spi_of_match); + +/** + * spi_davinci_get_pdata - Get platform data from DTS binding + * @pdev: ptr to platform data + * @dspi: ptr to driver data + * + * Parses and populates pdata in dspi from device tree bindings. + * + * NOTE: Not all platform data params are supported currently. + */ +static int spi_davinci_get_pdata(struct platform_device *pdev, + struct davinci_spi *dspi) +{ + struct device_node *node = pdev->dev.of_node; + struct davinci_spi_platform_data *pdata; + unsigned int num_cs, intr_line = 0; + const struct of_device_id *match; + + pdata = &dspi->pdata; + + pdata->version = SPI_VERSION_1; + match = of_match_device(davinci_spi_of_match, &pdev->dev); + if (!match) + return -ENODEV; + + /* match data has the SPI version number for SPI_VERSION_2 */ + if (match->data == (void *)SPI_VERSION_2) + pdata->version = SPI_VERSION_2; + + /* + * default num_cs is 1 and all chipsel are internal to the chip + * indicated by chip_sel being NULL or cs_gpios being NULL or + * set to -ENOENT. num-cs includes internal as well as gpios. + * indicated by chip_sel being NULL. GPIO based CS is not + * supported yet in DT bindings. + */ + num_cs = 1; + of_property_read_u32(node, "num-cs", &num_cs); + pdata->num_chipselect = num_cs; + of_property_read_u32(node, "ti,davinci-spi-intr-line", &intr_line); + pdata->intr_line = intr_line; + return 0; +} +#else +static struct davinci_spi_platform_data + *spi_davinci_get_pdata(struct platform_device *pdev, + struct davinci_spi *dspi) +{ + return -ENODEV; +} +#endif + +/** + * davinci_spi_probe - probe function for SPI Master Controller + * @pdev: platform_device structure which contains plateform specific data + * + * According to Linux Device Model this function will be invoked by Linux + * with platform_device struct which contains the device specific info. + * This function will map the SPI controller's memory, register IRQ, + * Reset SPI controller and setting its registers to default value. + * It will invoke spi_bitbang_start to create work queue so that client driver + * can register transfer method to work queue. + */ +static int davinci_spi_probe(struct platform_device *pdev) +{ + struct spi_master *master; + struct davinci_spi *dspi; + struct davinci_spi_platform_data *pdata; + struct resource *r; + resource_size_t dma_rx_chan = SPI_NO_RESOURCE; + resource_size_t dma_tx_chan = SPI_NO_RESOURCE; + int ret = 0; + u32 spipc0; + + master = spi_alloc_master(&pdev->dev, sizeof(struct davinci_spi)); + if (master == NULL) { + ret = -ENOMEM; + goto err; + } + + platform_set_drvdata(pdev, master); + + dspi = spi_master_get_devdata(master); + + if (dev_get_platdata(&pdev->dev)) { + pdata = dev_get_platdata(&pdev->dev); + dspi->pdata = *pdata; + } else { + /* update dspi pdata with that from the DT */ + ret = spi_davinci_get_pdata(pdev, dspi); + if (ret < 0) + goto free_master; + } + + /* pdata in dspi is now updated and point pdata to that */ + pdata = &dspi->pdata; + + dspi->bytes_per_word = devm_kzalloc(&pdev->dev, + sizeof(*dspi->bytes_per_word) * + pdata->num_chipselect, GFP_KERNEL); + if (dspi->bytes_per_word == NULL) { + ret = -ENOMEM; + goto free_master; + } + + r = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (r == NULL) { + ret = -ENOENT; + goto free_master; + } + + dspi->pbase = r->start; + + dspi->base = devm_ioremap_resource(&pdev->dev, r); + if (IS_ERR(dspi->base)) { + ret = PTR_ERR(dspi->base); + goto free_master; + } + + dspi->irq = platform_get_irq(pdev, 0); + if (dspi->irq <= 0) { + ret = -EINVAL; + goto free_master; + } + + ret = devm_request_threaded_irq(&pdev->dev, dspi->irq, davinci_spi_irq, + dummy_thread_fn, 0, dev_name(&pdev->dev), dspi); + if (ret) + goto free_master; + + dspi->bitbang.master = master; + + dspi->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(dspi->clk)) { + ret = -ENODEV; + goto free_master; + } + clk_prepare_enable(dspi->clk); + + master->dev.of_node = pdev->dev.of_node; + master->bus_num = pdev->id; + master->num_chipselect = pdata->num_chipselect; + master->bits_per_word_mask = SPI_BPW_RANGE_MASK(2, 16); + master->setup = davinci_spi_setup; + master->cleanup = davinci_spi_cleanup; + + dspi->bitbang.chipselect = davinci_spi_chipselect; + dspi->bitbang.setup_transfer = davinci_spi_setup_transfer; + + dspi->version = pdata->version; + + dspi->bitbang.flags = SPI_NO_CS | SPI_LSB_FIRST | SPI_LOOP; + if (dspi->version == SPI_VERSION_2) + dspi->bitbang.flags |= SPI_READY; + + if (pdev->dev.of_node) { + int i; + + for (i = 0; i < pdata->num_chipselect; i++) { + int cs_gpio = of_get_named_gpio(pdev->dev.of_node, + "cs-gpios", i); + + if (cs_gpio == -EPROBE_DEFER) { + ret = cs_gpio; + goto free_clk; + } + + if (gpio_is_valid(cs_gpio)) { + ret = devm_gpio_request(&pdev->dev, cs_gpio, + dev_name(&pdev->dev)); + if (ret) + goto free_clk; + } + } + } + + r = platform_get_resource(pdev, IORESOURCE_DMA, 0); + if (r) + dma_rx_chan = r->start; + r = platform_get_resource(pdev, IORESOURCE_DMA, 1); + if (r) + dma_tx_chan = r->start; + + dspi->bitbang.txrx_bufs = davinci_spi_bufs; + if (dma_rx_chan != SPI_NO_RESOURCE && + dma_tx_chan != SPI_NO_RESOURCE) { + dspi->dma_rx_chnum = dma_rx_chan; + dspi->dma_tx_chnum = dma_tx_chan; + + ret = davinci_spi_request_dma(dspi); + if (ret) + goto free_clk; + + dev_info(&pdev->dev, "DMA: supported\n"); + dev_info(&pdev->dev, "DMA: RX channel: %pa, TX channel: %pa, event queue: %d\n", + &dma_rx_chan, &dma_tx_chan, + pdata->dma_event_q); + } + + dspi->get_rx = davinci_spi_rx_buf_u8; + dspi->get_tx = davinci_spi_tx_buf_u8; + + init_completion(&dspi->done); + + /* Reset In/OUT SPI module */ + iowrite32(0, dspi->base + SPIGCR0); + udelay(100); + iowrite32(1, dspi->base + SPIGCR0); + + /* Set up SPIPC0. CS and ENA init is done in davinci_spi_setup */ + spipc0 = SPIPC0_DIFUN_MASK | SPIPC0_DOFUN_MASK | SPIPC0_CLKFUN_MASK; + iowrite32(spipc0, dspi->base + SPIPC0); + + if (pdata->intr_line) + iowrite32(SPI_INTLVL_1, dspi->base + SPILVL); + else + iowrite32(SPI_INTLVL_0, dspi->base + SPILVL); + + iowrite32(CS_DEFAULT, dspi->base + SPIDEF); + + /* master mode default */ + set_io_bits(dspi->base + SPIGCR1, SPIGCR1_CLKMOD_MASK); + set_io_bits(dspi->base + SPIGCR1, SPIGCR1_MASTER_MASK); + set_io_bits(dspi->base + SPIGCR1, SPIGCR1_POWERDOWN_MASK); + + ret = spi_bitbang_start(&dspi->bitbang); + if (ret) + goto free_dma; + + dev_info(&pdev->dev, "Controller at 0x%p\n", dspi->base); + + return ret; + +free_dma: + dma_release_channel(dspi->dma_rx); + dma_release_channel(dspi->dma_tx); +free_clk: + clk_disable_unprepare(dspi->clk); +free_master: + spi_master_put(master); +err: + return ret; +} + +/** + * davinci_spi_remove - remove function for SPI Master Controller + * @pdev: platform_device structure which contains plateform specific data + * + * This function will do the reverse action of davinci_spi_probe function + * It will free the IRQ and SPI controller's memory region. + * It will also call spi_bitbang_stop to destroy the work queue which was + * created by spi_bitbang_start. + */ +static int davinci_spi_remove(struct platform_device *pdev) +{ + struct davinci_spi *dspi; + struct spi_master *master; + + master = platform_get_drvdata(pdev); + dspi = spi_master_get_devdata(master); + + spi_bitbang_stop(&dspi->bitbang); + + clk_disable_unprepare(dspi->clk); + spi_master_put(master); + + return 0; +} + +static struct platform_driver davinci_spi_driver = { + .driver = { + .name = "spi_davinci", + .of_match_table = of_match_ptr(davinci_spi_of_match), + }, + .probe = davinci_spi_probe, + .remove = davinci_spi_remove, +}; +module_platform_driver(davinci_spi_driver); + +MODULE_DESCRIPTION("TI DaVinci SPI Master Controller Driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/spi/spi-dln2.c b/drivers/spi/spi-dln2.c new file mode 100644 index 000000000..3b7d91d94 --- /dev/null +++ b/drivers/spi/spi-dln2.c @@ -0,0 +1,881 @@ +/* + * Driver for the Diolan DLN-2 USB-SPI adapter + * + * Copyright (c) 2014 Intel Corporation + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation, version 2. + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/mfd/dln2.h> +#include <linux/spi/spi.h> +#include <linux/pm_runtime.h> +#include <asm/unaligned.h> + +#define DLN2_SPI_MODULE_ID 0x02 +#define DLN2_SPI_CMD(cmd) DLN2_CMD(cmd, DLN2_SPI_MODULE_ID) + +/* SPI commands */ +#define DLN2_SPI_GET_PORT_COUNT DLN2_SPI_CMD(0x00) +#define DLN2_SPI_ENABLE DLN2_SPI_CMD(0x11) +#define DLN2_SPI_DISABLE DLN2_SPI_CMD(0x12) +#define DLN2_SPI_IS_ENABLED DLN2_SPI_CMD(0x13) +#define DLN2_SPI_SET_MODE DLN2_SPI_CMD(0x14) +#define DLN2_SPI_GET_MODE DLN2_SPI_CMD(0x15) +#define DLN2_SPI_SET_FRAME_SIZE DLN2_SPI_CMD(0x16) +#define DLN2_SPI_GET_FRAME_SIZE DLN2_SPI_CMD(0x17) +#define DLN2_SPI_SET_FREQUENCY DLN2_SPI_CMD(0x18) +#define DLN2_SPI_GET_FREQUENCY DLN2_SPI_CMD(0x19) +#define DLN2_SPI_READ_WRITE DLN2_SPI_CMD(0x1A) +#define DLN2_SPI_READ DLN2_SPI_CMD(0x1B) +#define DLN2_SPI_WRITE DLN2_SPI_CMD(0x1C) +#define DLN2_SPI_SET_DELAY_BETWEEN_SS DLN2_SPI_CMD(0x20) +#define DLN2_SPI_GET_DELAY_BETWEEN_SS DLN2_SPI_CMD(0x21) +#define DLN2_SPI_SET_DELAY_AFTER_SS DLN2_SPI_CMD(0x22) +#define DLN2_SPI_GET_DELAY_AFTER_SS DLN2_SPI_CMD(0x23) +#define DLN2_SPI_SET_DELAY_BETWEEN_FRAMES DLN2_SPI_CMD(0x24) +#define DLN2_SPI_GET_DELAY_BETWEEN_FRAMES DLN2_SPI_CMD(0x25) +#define DLN2_SPI_SET_SS DLN2_SPI_CMD(0x26) +#define DLN2_SPI_GET_SS DLN2_SPI_CMD(0x27) +#define DLN2_SPI_RELEASE_SS DLN2_SPI_CMD(0x28) +#define DLN2_SPI_SS_VARIABLE_ENABLE DLN2_SPI_CMD(0x2B) +#define DLN2_SPI_SS_VARIABLE_DISABLE DLN2_SPI_CMD(0x2C) +#define DLN2_SPI_SS_VARIABLE_IS_ENABLED DLN2_SPI_CMD(0x2D) +#define DLN2_SPI_SS_AAT_ENABLE DLN2_SPI_CMD(0x2E) +#define DLN2_SPI_SS_AAT_DISABLE DLN2_SPI_CMD(0x2F) +#define DLN2_SPI_SS_AAT_IS_ENABLED DLN2_SPI_CMD(0x30) +#define DLN2_SPI_SS_BETWEEN_FRAMES_ENABLE DLN2_SPI_CMD(0x31) +#define DLN2_SPI_SS_BETWEEN_FRAMES_DISABLE DLN2_SPI_CMD(0x32) +#define DLN2_SPI_SS_BETWEEN_FRAMES_IS_ENABLED DLN2_SPI_CMD(0x33) +#define DLN2_SPI_SET_CPHA DLN2_SPI_CMD(0x34) +#define DLN2_SPI_GET_CPHA DLN2_SPI_CMD(0x35) +#define DLN2_SPI_SET_CPOL DLN2_SPI_CMD(0x36) +#define DLN2_SPI_GET_CPOL DLN2_SPI_CMD(0x37) +#define DLN2_SPI_SS_MULTI_ENABLE DLN2_SPI_CMD(0x38) +#define DLN2_SPI_SS_MULTI_DISABLE DLN2_SPI_CMD(0x39) +#define DLN2_SPI_SS_MULTI_IS_ENABLED DLN2_SPI_CMD(0x3A) +#define DLN2_SPI_GET_SUPPORTED_MODES DLN2_SPI_CMD(0x40) +#define DLN2_SPI_GET_SUPPORTED_CPHA_VALUES DLN2_SPI_CMD(0x41) +#define DLN2_SPI_GET_SUPPORTED_CPOL_VALUES DLN2_SPI_CMD(0x42) +#define DLN2_SPI_GET_SUPPORTED_FRAME_SIZES DLN2_SPI_CMD(0x43) +#define DLN2_SPI_GET_SS_COUNT DLN2_SPI_CMD(0x44) +#define DLN2_SPI_GET_MIN_FREQUENCY DLN2_SPI_CMD(0x45) +#define DLN2_SPI_GET_MAX_FREQUENCY DLN2_SPI_CMD(0x46) +#define DLN2_SPI_GET_MIN_DELAY_BETWEEN_SS DLN2_SPI_CMD(0x47) +#define DLN2_SPI_GET_MAX_DELAY_BETWEEN_SS DLN2_SPI_CMD(0x48) +#define DLN2_SPI_GET_MIN_DELAY_AFTER_SS DLN2_SPI_CMD(0x49) +#define DLN2_SPI_GET_MAX_DELAY_AFTER_SS DLN2_SPI_CMD(0x4A) +#define DLN2_SPI_GET_MIN_DELAY_BETWEEN_FRAMES DLN2_SPI_CMD(0x4B) +#define DLN2_SPI_GET_MAX_DELAY_BETWEEN_FRAMES DLN2_SPI_CMD(0x4C) + +#define DLN2_SPI_MAX_XFER_SIZE 256 +#define DLN2_SPI_BUF_SIZE (DLN2_SPI_MAX_XFER_SIZE + 16) +#define DLN2_SPI_ATTR_LEAVE_SS_LOW BIT(0) +#define DLN2_TRANSFERS_WAIT_COMPLETE 1 +#define DLN2_TRANSFERS_CANCEL 0 +#define DLN2_RPM_AUTOSUSPEND_TIMEOUT 2000 + +struct dln2_spi { + struct platform_device *pdev; + struct spi_master *master; + u8 port; + + /* + * This buffer will be used mainly for read/write operations. Since + * they're quite large, we cannot use the stack. Protection is not + * needed because all SPI communication is serialized by the SPI core. + */ + void *buf; + + u8 bpw; + u32 speed; + u16 mode; + u8 cs; +}; + +/* + * Enable/Disable SPI module. The disable command will wait for transfers to + * complete first. + */ +static int dln2_spi_enable(struct dln2_spi *dln2, bool enable) +{ + u16 cmd; + struct { + u8 port; + u8 wait_for_completion; + } tx; + unsigned len = sizeof(tx); + + tx.port = dln2->port; + + if (enable) { + cmd = DLN2_SPI_ENABLE; + len -= sizeof(tx.wait_for_completion); + } else { + tx.wait_for_completion = DLN2_TRANSFERS_WAIT_COMPLETE; + cmd = DLN2_SPI_DISABLE; + } + + return dln2_transfer_tx(dln2->pdev, cmd, &tx, len); +} + +/* + * Select/unselect multiple CS lines. The selected lines will be automatically + * toggled LOW/HIGH by the board firmware during transfers, provided they're + * enabled first. + * + * Ex: cs_mask = 0x03 -> CS0 & CS1 will be selected and the next WR/RD operation + * will toggle the lines LOW/HIGH automatically. + */ +static int dln2_spi_cs_set(struct dln2_spi *dln2, u8 cs_mask) +{ + struct { + u8 port; + u8 cs; + } tx; + + tx.port = dln2->port; + + /* + * According to Diolan docs, "a slave device can be selected by changing + * the corresponding bit value to 0". The rest must be set to 1. Hence + * the bitwise NOT in front. + */ + tx.cs = ~cs_mask; + + return dln2_transfer_tx(dln2->pdev, DLN2_SPI_SET_SS, &tx, sizeof(tx)); +} + +/* + * Select one CS line. The other lines will be un-selected. + */ +static int dln2_spi_cs_set_one(struct dln2_spi *dln2, u8 cs) +{ + return dln2_spi_cs_set(dln2, BIT(cs)); +} + +/* + * Enable/disable CS lines for usage. The module has to be disabled first. + */ +static int dln2_spi_cs_enable(struct dln2_spi *dln2, u8 cs_mask, bool enable) +{ + struct { + u8 port; + u8 cs; + } tx; + u16 cmd; + + tx.port = dln2->port; + tx.cs = cs_mask; + cmd = enable ? DLN2_SPI_SS_MULTI_ENABLE : DLN2_SPI_SS_MULTI_DISABLE; + + return dln2_transfer_tx(dln2->pdev, cmd, &tx, sizeof(tx)); +} + +static int dln2_spi_cs_enable_all(struct dln2_spi *dln2, bool enable) +{ + u8 cs_mask = GENMASK(dln2->master->num_chipselect - 1, 0); + + return dln2_spi_cs_enable(dln2, cs_mask, enable); +} + +static int dln2_spi_get_cs_num(struct dln2_spi *dln2, u16 *cs_num) +{ + int ret; + struct { + u8 port; + } tx; + struct { + __le16 cs_count; + } rx; + unsigned rx_len = sizeof(rx); + + tx.port = dln2->port; + ret = dln2_transfer(dln2->pdev, DLN2_SPI_GET_SS_COUNT, &tx, sizeof(tx), + &rx, &rx_len); + if (ret < 0) + return ret; + if (rx_len < sizeof(rx)) + return -EPROTO; + + *cs_num = le16_to_cpu(rx.cs_count); + + dev_dbg(&dln2->pdev->dev, "cs_num = %d\n", *cs_num); + + return 0; +} + +static int dln2_spi_get_speed(struct dln2_spi *dln2, u16 cmd, u32 *freq) +{ + int ret; + struct { + u8 port; + } tx; + struct { + __le32 speed; + } rx; + unsigned rx_len = sizeof(rx); + + tx.port = dln2->port; + + ret = dln2_transfer(dln2->pdev, cmd, &tx, sizeof(tx), &rx, &rx_len); + if (ret < 0) + return ret; + if (rx_len < sizeof(rx)) + return -EPROTO; + + *freq = le32_to_cpu(rx.speed); + + return 0; +} + +/* + * Get bus min/max frequencies. + */ +static int dln2_spi_get_speed_range(struct dln2_spi *dln2, u32 *fmin, u32 *fmax) +{ + int ret; + + ret = dln2_spi_get_speed(dln2, DLN2_SPI_GET_MIN_FREQUENCY, fmin); + if (ret < 0) + return ret; + + ret = dln2_spi_get_speed(dln2, DLN2_SPI_GET_MAX_FREQUENCY, fmax); + if (ret < 0) + return ret; + + dev_dbg(&dln2->pdev->dev, "freq_min = %d, freq_max = %d\n", + *fmin, *fmax); + + return 0; +} + +/* + * Set the bus speed. The module will automatically round down to the closest + * available frequency and returns it. The module has to be disabled first. + */ +static int dln2_spi_set_speed(struct dln2_spi *dln2, u32 speed) +{ + int ret; + struct { + u8 port; + __le32 speed; + } __packed tx; + struct { + __le32 speed; + } rx; + int rx_len = sizeof(rx); + + tx.port = dln2->port; + tx.speed = cpu_to_le32(speed); + + ret = dln2_transfer(dln2->pdev, DLN2_SPI_SET_FREQUENCY, &tx, sizeof(tx), + &rx, &rx_len); + if (ret < 0) + return ret; + if (rx_len < sizeof(rx)) + return -EPROTO; + + return 0; +} + +/* + * Change CPOL & CPHA. The module has to be disabled first. + */ +static int dln2_spi_set_mode(struct dln2_spi *dln2, u8 mode) +{ + struct { + u8 port; + u8 mode; + } tx; + + tx.port = dln2->port; + tx.mode = mode; + + return dln2_transfer_tx(dln2->pdev, DLN2_SPI_SET_MODE, &tx, sizeof(tx)); +} + +/* + * Change frame size. The module has to be disabled first. + */ +static int dln2_spi_set_bpw(struct dln2_spi *dln2, u8 bpw) +{ + struct { + u8 port; + u8 bpw; + } tx; + + tx.port = dln2->port; + tx.bpw = bpw; + + return dln2_transfer_tx(dln2->pdev, DLN2_SPI_SET_FRAME_SIZE, + &tx, sizeof(tx)); +} + +static int dln2_spi_get_supported_frame_sizes(struct dln2_spi *dln2, + u32 *bpw_mask) +{ + int ret; + struct { + u8 port; + } tx; + struct { + u8 count; + u8 frame_sizes[36]; + } *rx = dln2->buf; + unsigned rx_len = sizeof(*rx); + int i; + + tx.port = dln2->port; + + ret = dln2_transfer(dln2->pdev, DLN2_SPI_GET_SUPPORTED_FRAME_SIZES, + &tx, sizeof(tx), rx, &rx_len); + if (ret < 0) + return ret; + if (rx_len < sizeof(*rx)) + return -EPROTO; + if (rx->count > ARRAY_SIZE(rx->frame_sizes)) + return -EPROTO; + + *bpw_mask = 0; + for (i = 0; i < rx->count; i++) + *bpw_mask |= BIT(rx->frame_sizes[i] - 1); + + dev_dbg(&dln2->pdev->dev, "bpw_mask = 0x%X\n", *bpw_mask); + + return 0; +} + +/* + * Copy the data to DLN2 buffer and change the byte order to LE, requested by + * DLN2 module. SPI core makes sure that the data length is a multiple of word + * size. + */ +static int dln2_spi_copy_to_buf(u8 *dln2_buf, const u8 *src, u16 len, u8 bpw) +{ +#ifdef __LITTLE_ENDIAN + memcpy(dln2_buf, src, len); +#else + if (bpw <= 8) { + memcpy(dln2_buf, src, len); + } else if (bpw <= 16) { + __le16 *d = (__le16 *)dln2_buf; + u16 *s = (u16 *)src; + + len = len / 2; + while (len--) + *d++ = cpu_to_le16p(s++); + } else { + __le32 *d = (__le32 *)dln2_buf; + u32 *s = (u32 *)src; + + len = len / 4; + while (len--) + *d++ = cpu_to_le32p(s++); + } +#endif + + return 0; +} + +/* + * Copy the data from DLN2 buffer and convert to CPU byte order since the DLN2 + * buffer is LE ordered. SPI core makes sure that the data length is a multiple + * of word size. The RX dln2_buf is 2 byte aligned so, for BE, we have to make + * sure we avoid unaligned accesses for 32 bit case. + */ +static int dln2_spi_copy_from_buf(u8 *dest, const u8 *dln2_buf, u16 len, u8 bpw) +{ +#ifdef __LITTLE_ENDIAN + memcpy(dest, dln2_buf, len); +#else + if (bpw <= 8) { + memcpy(dest, dln2_buf, len); + } else if (bpw <= 16) { + u16 *d = (u16 *)dest; + __le16 *s = (__le16 *)dln2_buf; + + len = len / 2; + while (len--) + *d++ = le16_to_cpup(s++); + } else { + u32 *d = (u32 *)dest; + __le32 *s = (__le32 *)dln2_buf; + + len = len / 4; + while (len--) + *d++ = get_unaligned_le32(s++); + } +#endif + + return 0; +} + +/* + * Perform one write operation. + */ +static int dln2_spi_write_one(struct dln2_spi *dln2, const u8 *data, + u16 data_len, u8 attr) +{ + struct { + u8 port; + __le16 size; + u8 attr; + u8 buf[DLN2_SPI_MAX_XFER_SIZE]; + } __packed *tx = dln2->buf; + unsigned tx_len; + + BUILD_BUG_ON(sizeof(*tx) > DLN2_SPI_BUF_SIZE); + + if (data_len > DLN2_SPI_MAX_XFER_SIZE) + return -EINVAL; + + tx->port = dln2->port; + tx->size = cpu_to_le16(data_len); + tx->attr = attr; + + dln2_spi_copy_to_buf(tx->buf, data, data_len, dln2->bpw); + + tx_len = sizeof(*tx) + data_len - DLN2_SPI_MAX_XFER_SIZE; + return dln2_transfer_tx(dln2->pdev, DLN2_SPI_WRITE, tx, tx_len); +} + +/* + * Perform one read operation. + */ +static int dln2_spi_read_one(struct dln2_spi *dln2, u8 *data, + u16 data_len, u8 attr) +{ + int ret; + struct { + u8 port; + __le16 size; + u8 attr; + } __packed tx; + struct { + __le16 size; + u8 buf[DLN2_SPI_MAX_XFER_SIZE]; + } __packed *rx = dln2->buf; + unsigned rx_len = sizeof(*rx); + + BUILD_BUG_ON(sizeof(*rx) > DLN2_SPI_BUF_SIZE); + + if (data_len > DLN2_SPI_MAX_XFER_SIZE) + return -EINVAL; + + tx.port = dln2->port; + tx.size = cpu_to_le16(data_len); + tx.attr = attr; + + ret = dln2_transfer(dln2->pdev, DLN2_SPI_READ, &tx, sizeof(tx), + rx, &rx_len); + if (ret < 0) + return ret; + if (rx_len < sizeof(rx->size) + data_len) + return -EPROTO; + if (le16_to_cpu(rx->size) != data_len) + return -EPROTO; + + dln2_spi_copy_from_buf(data, rx->buf, data_len, dln2->bpw); + + return 0; +} + +/* + * Perform one write & read operation. + */ +static int dln2_spi_read_write_one(struct dln2_spi *dln2, const u8 *tx_data, + u8 *rx_data, u16 data_len, u8 attr) +{ + int ret; + struct { + u8 port; + __le16 size; + u8 attr; + u8 buf[DLN2_SPI_MAX_XFER_SIZE]; + } __packed *tx; + struct { + __le16 size; + u8 buf[DLN2_SPI_MAX_XFER_SIZE]; + } __packed *rx; + unsigned tx_len, rx_len; + + BUILD_BUG_ON(sizeof(*tx) > DLN2_SPI_BUF_SIZE || + sizeof(*rx) > DLN2_SPI_BUF_SIZE); + + if (data_len > DLN2_SPI_MAX_XFER_SIZE) + return -EINVAL; + + /* + * Since this is a pseudo full-duplex communication, we're perfectly + * safe to use the same buffer for both tx and rx. When DLN2 sends the + * response back, with the rx data, we don't need the tx buffer anymore. + */ + tx = dln2->buf; + rx = dln2->buf; + + tx->port = dln2->port; + tx->size = cpu_to_le16(data_len); + tx->attr = attr; + + dln2_spi_copy_to_buf(tx->buf, tx_data, data_len, dln2->bpw); + + tx_len = sizeof(*tx) + data_len - DLN2_SPI_MAX_XFER_SIZE; + rx_len = sizeof(*rx); + + ret = dln2_transfer(dln2->pdev, DLN2_SPI_READ_WRITE, tx, tx_len, + rx, &rx_len); + if (ret < 0) + return ret; + if (rx_len < sizeof(rx->size) + data_len) + return -EPROTO; + if (le16_to_cpu(rx->size) != data_len) + return -EPROTO; + + dln2_spi_copy_from_buf(rx_data, rx->buf, data_len, dln2->bpw); + + return 0; +} + +/* + * Read/Write wrapper. It will automatically split an operation into multiple + * single ones due to device buffer constraints. + */ +static int dln2_spi_rdwr(struct dln2_spi *dln2, const u8 *tx_data, + u8 *rx_data, u16 data_len, u8 attr) { + int ret; + u16 len; + u8 temp_attr; + u16 remaining = data_len; + u16 offset; + + do { + if (remaining > DLN2_SPI_MAX_XFER_SIZE) { + len = DLN2_SPI_MAX_XFER_SIZE; + temp_attr = DLN2_SPI_ATTR_LEAVE_SS_LOW; + } else { + len = remaining; + temp_attr = attr; + } + + offset = data_len - remaining; + + if (tx_data && rx_data) { + ret = dln2_spi_read_write_one(dln2, + tx_data + offset, + rx_data + offset, + len, temp_attr); + } else if (tx_data) { + ret = dln2_spi_write_one(dln2, + tx_data + offset, + len, temp_attr); + } else if (rx_data) { + ret = dln2_spi_read_one(dln2, + rx_data + offset, + len, temp_attr); + } else { + return -EINVAL; + } + + if (ret < 0) + return ret; + + remaining -= len; + } while (remaining); + + return 0; +} + +static int dln2_spi_prepare_message(struct spi_master *master, + struct spi_message *message) +{ + int ret; + struct dln2_spi *dln2 = spi_master_get_devdata(master); + struct spi_device *spi = message->spi; + + if (dln2->cs != spi->chip_select) { + ret = dln2_spi_cs_set_one(dln2, spi->chip_select); + if (ret < 0) + return ret; + + dln2->cs = spi->chip_select; + } + + return 0; +} + +static int dln2_spi_transfer_setup(struct dln2_spi *dln2, u32 speed, + u8 bpw, u8 mode) +{ + int ret; + bool bus_setup_change; + + bus_setup_change = dln2->speed != speed || dln2->mode != mode || + dln2->bpw != bpw; + + if (!bus_setup_change) + return 0; + + ret = dln2_spi_enable(dln2, false); + if (ret < 0) + return ret; + + if (dln2->speed != speed) { + ret = dln2_spi_set_speed(dln2, speed); + if (ret < 0) + return ret; + + dln2->speed = speed; + } + + if (dln2->mode != mode) { + ret = dln2_spi_set_mode(dln2, mode & 0x3); + if (ret < 0) + return ret; + + dln2->mode = mode; + } + + if (dln2->bpw != bpw) { + ret = dln2_spi_set_bpw(dln2, bpw); + if (ret < 0) + return ret; + + dln2->bpw = bpw; + } + + return dln2_spi_enable(dln2, true); +} + +static int dln2_spi_transfer_one(struct spi_master *master, + struct spi_device *spi, + struct spi_transfer *xfer) +{ + struct dln2_spi *dln2 = spi_master_get_devdata(master); + int status; + u8 attr = 0; + + status = dln2_spi_transfer_setup(dln2, xfer->speed_hz, + xfer->bits_per_word, + spi->mode); + if (status < 0) { + dev_err(&dln2->pdev->dev, "Cannot setup transfer\n"); + return status; + } + + if (!xfer->cs_change && !spi_transfer_is_last(master, xfer)) + attr = DLN2_SPI_ATTR_LEAVE_SS_LOW; + + status = dln2_spi_rdwr(dln2, xfer->tx_buf, xfer->rx_buf, + xfer->len, attr); + if (status < 0) + dev_err(&dln2->pdev->dev, "write/read failed!\n"); + + return status; +} + +static int dln2_spi_probe(struct platform_device *pdev) +{ + struct spi_master *master; + struct dln2_spi *dln2; + struct dln2_platform_data *pdata = dev_get_platdata(&pdev->dev); + int ret; + + master = spi_alloc_master(&pdev->dev, sizeof(*dln2)); + if (!master) + return -ENOMEM; + + platform_set_drvdata(pdev, master); + + dln2 = spi_master_get_devdata(master); + + dln2->buf = devm_kmalloc(&pdev->dev, DLN2_SPI_BUF_SIZE, GFP_KERNEL); + if (!dln2->buf) { + ret = -ENOMEM; + goto exit_free_master; + } + + dln2->master = master; + dln2->pdev = pdev; + dln2->port = pdata->port; + /* cs/mode can never be 0xff, so the first transfer will set them */ + dln2->cs = 0xff; + dln2->mode = 0xff; + + /* disable SPI module before continuing with the setup */ + ret = dln2_spi_enable(dln2, false); + if (ret < 0) { + dev_err(&pdev->dev, "Failed to disable SPI module\n"); + goto exit_free_master; + } + + ret = dln2_spi_get_cs_num(dln2, &master->num_chipselect); + if (ret < 0) { + dev_err(&pdev->dev, "Failed to get number of CS pins\n"); + goto exit_free_master; + } + + ret = dln2_spi_get_speed_range(dln2, + &master->min_speed_hz, + &master->max_speed_hz); + if (ret < 0) { + dev_err(&pdev->dev, "Failed to read bus min/max freqs\n"); + goto exit_free_master; + } + + ret = dln2_spi_get_supported_frame_sizes(dln2, + &master->bits_per_word_mask); + if (ret < 0) { + dev_err(&pdev->dev, "Failed to read supported frame sizes\n"); + goto exit_free_master; + } + + ret = dln2_spi_cs_enable_all(dln2, true); + if (ret < 0) { + dev_err(&pdev->dev, "Failed to enable CS pins\n"); + goto exit_free_master; + } + + master->bus_num = -1; + master->mode_bits = SPI_CPOL | SPI_CPHA; + master->prepare_message = dln2_spi_prepare_message; + master->transfer_one = dln2_spi_transfer_one; + master->auto_runtime_pm = true; + + /* enable SPI module, we're good to go */ + ret = dln2_spi_enable(dln2, true); + if (ret < 0) { + dev_err(&pdev->dev, "Failed to enable SPI module\n"); + goto exit_free_master; + } + + pm_runtime_set_autosuspend_delay(&pdev->dev, + DLN2_RPM_AUTOSUSPEND_TIMEOUT); + pm_runtime_use_autosuspend(&pdev->dev); + pm_runtime_set_active(&pdev->dev); + pm_runtime_enable(&pdev->dev); + + ret = devm_spi_register_master(&pdev->dev, master); + if (ret < 0) { + dev_err(&pdev->dev, "Failed to register master\n"); + goto exit_register; + } + + return ret; + +exit_register: + pm_runtime_disable(&pdev->dev); + pm_runtime_set_suspended(&pdev->dev); + + if (dln2_spi_enable(dln2, false) < 0) + dev_err(&pdev->dev, "Failed to disable SPI module\n"); +exit_free_master: + spi_master_put(master); + + return ret; +} + +static int dln2_spi_remove(struct platform_device *pdev) +{ + struct spi_master *master = spi_master_get(platform_get_drvdata(pdev)); + struct dln2_spi *dln2 = spi_master_get_devdata(master); + + pm_runtime_disable(&pdev->dev); + + if (dln2_spi_enable(dln2, false) < 0) + dev_err(&pdev->dev, "Failed to disable SPI module\n"); + + return 0; +} + +#ifdef CONFIG_PM_SLEEP +static int dln2_spi_suspend(struct device *dev) +{ + int ret; + struct spi_master *master = dev_get_drvdata(dev); + struct dln2_spi *dln2 = spi_master_get_devdata(master); + + ret = spi_master_suspend(master); + if (ret < 0) + return ret; + + if (!pm_runtime_suspended(dev)) { + ret = dln2_spi_enable(dln2, false); + if (ret < 0) + return ret; + } + + /* + * USB power may be cut off during sleep. Resetting the following + * parameters will force the board to be set up before first transfer. + */ + dln2->cs = 0xff; + dln2->speed = 0; + dln2->bpw = 0; + dln2->mode = 0xff; + + return 0; +} + +static int dln2_spi_resume(struct device *dev) +{ + int ret; + struct spi_master *master = dev_get_drvdata(dev); + struct dln2_spi *dln2 = spi_master_get_devdata(master); + + if (!pm_runtime_suspended(dev)) { + ret = dln2_spi_cs_enable_all(dln2, true); + if (ret < 0) + return ret; + + ret = dln2_spi_enable(dln2, true); + if (ret < 0) + return ret; + } + + return spi_master_resume(master); +} +#endif /* CONFIG_PM_SLEEP */ + +#ifdef CONFIG_PM +static int dln2_spi_runtime_suspend(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct dln2_spi *dln2 = spi_master_get_devdata(master); + + return dln2_spi_enable(dln2, false); +} + +static int dln2_spi_runtime_resume(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct dln2_spi *dln2 = spi_master_get_devdata(master); + + return dln2_spi_enable(dln2, true); +} +#endif /* CONFIG_PM */ + +static const struct dev_pm_ops dln2_spi_pm = { + SET_SYSTEM_SLEEP_PM_OPS(dln2_spi_suspend, dln2_spi_resume) + SET_RUNTIME_PM_OPS(dln2_spi_runtime_suspend, + dln2_spi_runtime_resume, NULL) +}; + +static struct platform_driver spi_dln2_driver = { + .driver = { + .name = "dln2-spi", + .pm = &dln2_spi_pm, + }, + .probe = dln2_spi_probe, + .remove = dln2_spi_remove, +}; +module_platform_driver(spi_dln2_driver); + +MODULE_DESCRIPTION("Driver for the Diolan DLN2 SPI master interface"); +MODULE_AUTHOR("Laurentiu Palcu <laurentiu.palcu@intel.com>"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:dln2-spi"); diff --git a/drivers/spi/spi-dw-mid.c b/drivers/spi/spi-dw-mid.c new file mode 100644 index 000000000..bb1052e74 --- /dev/null +++ b/drivers/spi/spi-dw-mid.c @@ -0,0 +1,330 @@ +/* + * Special handling for DW core on Intel MID platform + * + * Copyright (c) 2009, 2014 Intel Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + */ + +#include <linux/dma-mapping.h> +#include <linux/dmaengine.h> +#include <linux/interrupt.h> +#include <linux/slab.h> +#include <linux/spi/spi.h> +#include <linux/types.h> + +#include "spi-dw.h" + +#ifdef CONFIG_SPI_DW_MID_DMA +#include <linux/pci.h> +#include <linux/platform_data/dma-dw.h> + +#define RX_BUSY 0 +#define TX_BUSY 1 + +static struct dw_dma_slave mid_dma_tx = { .dst_id = 1 }; +static struct dw_dma_slave mid_dma_rx = { .src_id = 0 }; + +static bool mid_spi_dma_chan_filter(struct dma_chan *chan, void *param) +{ + struct dw_dma_slave *s = param; + + if (s->dma_dev != chan->device->dev) + return false; + + chan->private = s; + return true; +} + +static int mid_spi_dma_init(struct dw_spi *dws) +{ + struct pci_dev *dma_dev; + struct dw_dma_slave *tx = dws->dma_tx; + struct dw_dma_slave *rx = dws->dma_rx; + dma_cap_mask_t mask; + + /* + * Get pci device for DMA controller, currently it could only + * be the DMA controller of Medfield + */ + dma_dev = pci_get_device(PCI_VENDOR_ID_INTEL, 0x0827, NULL); + if (!dma_dev) + return -ENODEV; + + dma_cap_zero(mask); + dma_cap_set(DMA_SLAVE, mask); + + /* 1. Init rx channel */ + rx->dma_dev = &dma_dev->dev; + dws->rxchan = dma_request_channel(mask, mid_spi_dma_chan_filter, rx); + if (!dws->rxchan) + goto err_exit; + dws->master->dma_rx = dws->rxchan; + + /* 2. Init tx channel */ + tx->dma_dev = &dma_dev->dev; + dws->txchan = dma_request_channel(mask, mid_spi_dma_chan_filter, tx); + if (!dws->txchan) + goto free_rxchan; + dws->master->dma_tx = dws->txchan; + + dws->dma_inited = 1; + return 0; + +free_rxchan: + dma_release_channel(dws->rxchan); +err_exit: + return -EBUSY; +} + +static void mid_spi_dma_exit(struct dw_spi *dws) +{ + if (!dws->dma_inited) + return; + + dmaengine_terminate_all(dws->txchan); + dma_release_channel(dws->txchan); + + dmaengine_terminate_all(dws->rxchan); + dma_release_channel(dws->rxchan); +} + +static irqreturn_t dma_transfer(struct dw_spi *dws) +{ + u16 irq_status = dw_readl(dws, DW_SPI_ISR); + + if (!irq_status) + return IRQ_NONE; + + dw_readl(dws, DW_SPI_ICR); + spi_reset_chip(dws); + + dev_err(&dws->master->dev, "%s: FIFO overrun/underrun\n", __func__); + dws->master->cur_msg->status = -EIO; + spi_finalize_current_transfer(dws->master); + return IRQ_HANDLED; +} + +static bool mid_spi_can_dma(struct spi_master *master, struct spi_device *spi, + struct spi_transfer *xfer) +{ + struct dw_spi *dws = spi_master_get_devdata(master); + + if (!dws->dma_inited) + return false; + + return xfer->len > dws->fifo_len; +} + +static enum dma_slave_buswidth convert_dma_width(u32 dma_width) { + if (dma_width == 1) + return DMA_SLAVE_BUSWIDTH_1_BYTE; + else if (dma_width == 2) + return DMA_SLAVE_BUSWIDTH_2_BYTES; + + return DMA_SLAVE_BUSWIDTH_UNDEFINED; +} + +/* + * dws->dma_chan_busy is set before the dma transfer starts, callback for tx + * channel will clear a corresponding bit. + */ +static void dw_spi_dma_tx_done(void *arg) +{ + struct dw_spi *dws = arg; + + clear_bit(TX_BUSY, &dws->dma_chan_busy); + if (test_bit(RX_BUSY, &dws->dma_chan_busy)) + return; + spi_finalize_current_transfer(dws->master); +} + +static struct dma_async_tx_descriptor *dw_spi_dma_prepare_tx(struct dw_spi *dws, + struct spi_transfer *xfer) +{ + struct dma_slave_config txconf; + struct dma_async_tx_descriptor *txdesc; + + if (!xfer->tx_buf) + return NULL; + + txconf.direction = DMA_MEM_TO_DEV; + txconf.dst_addr = dws->dma_addr; + txconf.dst_maxburst = 16; + txconf.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; + txconf.dst_addr_width = convert_dma_width(dws->dma_width); + txconf.device_fc = false; + + dmaengine_slave_config(dws->txchan, &txconf); + + txdesc = dmaengine_prep_slave_sg(dws->txchan, + xfer->tx_sg.sgl, + xfer->tx_sg.nents, + DMA_MEM_TO_DEV, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + if (!txdesc) + return NULL; + + txdesc->callback = dw_spi_dma_tx_done; + txdesc->callback_param = dws; + + return txdesc; +} + +/* + * dws->dma_chan_busy is set before the dma transfer starts, callback for rx + * channel will clear a corresponding bit. + */ +static void dw_spi_dma_rx_done(void *arg) +{ + struct dw_spi *dws = arg; + + clear_bit(RX_BUSY, &dws->dma_chan_busy); + if (test_bit(TX_BUSY, &dws->dma_chan_busy)) + return; + spi_finalize_current_transfer(dws->master); +} + +static struct dma_async_tx_descriptor *dw_spi_dma_prepare_rx(struct dw_spi *dws, + struct spi_transfer *xfer) +{ + struct dma_slave_config rxconf; + struct dma_async_tx_descriptor *rxdesc; + + if (!xfer->rx_buf) + return NULL; + + rxconf.direction = DMA_DEV_TO_MEM; + rxconf.src_addr = dws->dma_addr; + rxconf.src_maxburst = 16; + rxconf.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; + rxconf.src_addr_width = convert_dma_width(dws->dma_width); + rxconf.device_fc = false; + + dmaengine_slave_config(dws->rxchan, &rxconf); + + rxdesc = dmaengine_prep_slave_sg(dws->rxchan, + xfer->rx_sg.sgl, + xfer->rx_sg.nents, + DMA_DEV_TO_MEM, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + if (!rxdesc) + return NULL; + + rxdesc->callback = dw_spi_dma_rx_done; + rxdesc->callback_param = dws; + + return rxdesc; +} + +static int mid_spi_dma_setup(struct dw_spi *dws, struct spi_transfer *xfer) +{ + u16 dma_ctrl = 0; + + dw_writel(dws, DW_SPI_DMARDLR, 0xf); + dw_writel(dws, DW_SPI_DMATDLR, 0x10); + + if (xfer->tx_buf) + dma_ctrl |= SPI_DMA_TDMAE; + if (xfer->rx_buf) + dma_ctrl |= SPI_DMA_RDMAE; + dw_writel(dws, DW_SPI_DMACR, dma_ctrl); + + /* Set the interrupt mask */ + spi_umask_intr(dws, SPI_INT_TXOI | SPI_INT_RXUI | SPI_INT_RXOI); + + dws->transfer_handler = dma_transfer; + + return 0; +} + +static int mid_spi_dma_transfer(struct dw_spi *dws, struct spi_transfer *xfer) +{ + struct dma_async_tx_descriptor *txdesc, *rxdesc; + + /* Prepare the TX dma transfer */ + txdesc = dw_spi_dma_prepare_tx(dws, xfer); + + /* Prepare the RX dma transfer */ + rxdesc = dw_spi_dma_prepare_rx(dws, xfer); + + /* rx must be started before tx due to spi instinct */ + if (rxdesc) { + set_bit(RX_BUSY, &dws->dma_chan_busy); + dmaengine_submit(rxdesc); + dma_async_issue_pending(dws->rxchan); + } + + if (txdesc) { + set_bit(TX_BUSY, &dws->dma_chan_busy); + dmaengine_submit(txdesc); + dma_async_issue_pending(dws->txchan); + } + + return 0; +} + +static void mid_spi_dma_stop(struct dw_spi *dws) +{ + if (test_bit(TX_BUSY, &dws->dma_chan_busy)) { + dmaengine_terminate_all(dws->txchan); + clear_bit(TX_BUSY, &dws->dma_chan_busy); + } + if (test_bit(RX_BUSY, &dws->dma_chan_busy)) { + dmaengine_terminate_all(dws->rxchan); + clear_bit(RX_BUSY, &dws->dma_chan_busy); + } +} + +static struct dw_spi_dma_ops mid_dma_ops = { + .dma_init = mid_spi_dma_init, + .dma_exit = mid_spi_dma_exit, + .dma_setup = mid_spi_dma_setup, + .can_dma = mid_spi_can_dma, + .dma_transfer = mid_spi_dma_transfer, + .dma_stop = mid_spi_dma_stop, +}; +#endif + +/* Some specific info for SPI0 controller on Intel MID */ + +/* HW info for MRST Clk Control Unit, 32b reg per controller */ +#define MRST_SPI_CLK_BASE 100000000 /* 100m */ +#define MRST_CLK_SPI_REG 0xff11d86c +#define CLK_SPI_BDIV_OFFSET 0 +#define CLK_SPI_BDIV_MASK 0x00000007 +#define CLK_SPI_CDIV_OFFSET 9 +#define CLK_SPI_CDIV_MASK 0x00000e00 +#define CLK_SPI_DISABLE_OFFSET 8 + +int dw_spi_mid_init(struct dw_spi *dws) +{ + void __iomem *clk_reg; + u32 clk_cdiv; + + clk_reg = ioremap_nocache(MRST_CLK_SPI_REG, 16); + if (!clk_reg) + return -ENOMEM; + + /* Get SPI controller operating freq info */ + clk_cdiv = readl(clk_reg + dws->bus_num * sizeof(u32)); + clk_cdiv &= CLK_SPI_CDIV_MASK; + clk_cdiv >>= CLK_SPI_CDIV_OFFSET; + dws->max_freq = MRST_SPI_CLK_BASE / (clk_cdiv + 1); + + iounmap(clk_reg); + +#ifdef CONFIG_SPI_DW_MID_DMA + dws->dma_tx = &mid_dma_tx; + dws->dma_rx = &mid_dma_rx; + dws->dma_ops = &mid_dma_ops; +#endif + return 0; +} diff --git a/drivers/spi/spi-dw-mmio.c b/drivers/spi/spi-dw-mmio.c new file mode 100644 index 000000000..eb03e1215 --- /dev/null +++ b/drivers/spi/spi-dw-mmio.c @@ -0,0 +1,145 @@ +/* + * Memory-mapped interface driver for DW SPI Core + * + * Copyright (c) 2010, Octasic semiconductor. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + */ + +#include <linux/clk.h> +#include <linux/err.h> +#include <linux/interrupt.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/spi/spi.h> +#include <linux/scatterlist.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_gpio.h> +#include <linux/of_platform.h> + +#include "spi-dw.h" + +#define DRIVER_NAME "dw_spi_mmio" + +struct dw_spi_mmio { + struct dw_spi dws; + struct clk *clk; +}; + +static int dw_spi_mmio_probe(struct platform_device *pdev) +{ + struct dw_spi_mmio *dwsmmio; + struct dw_spi *dws; + struct resource *mem; + int ret; + int num_cs; + + dwsmmio = devm_kzalloc(&pdev->dev, sizeof(struct dw_spi_mmio), + GFP_KERNEL); + if (!dwsmmio) + return -ENOMEM; + + dws = &dwsmmio->dws; + + /* Get basic io resource and map it */ + mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!mem) { + dev_err(&pdev->dev, "no mem resource?\n"); + return -EINVAL; + } + + dws->regs = devm_ioremap_resource(&pdev->dev, mem); + if (IS_ERR(dws->regs)) { + dev_err(&pdev->dev, "SPI region map failed\n"); + return PTR_ERR(dws->regs); + } + + dws->irq = platform_get_irq(pdev, 0); + if (dws->irq < 0) { + dev_err(&pdev->dev, "no irq resource?\n"); + return dws->irq; /* -ENXIO */ + } + + dwsmmio->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(dwsmmio->clk)) + return PTR_ERR(dwsmmio->clk); + ret = clk_prepare_enable(dwsmmio->clk); + if (ret) + return ret; + + dws->bus_num = pdev->id; + + dws->max_freq = clk_get_rate(dwsmmio->clk); + + num_cs = 4; + + if (pdev->dev.of_node) + of_property_read_u32(pdev->dev.of_node, "num-cs", &num_cs); + + dws->num_cs = num_cs; + + if (pdev->dev.of_node) { + int i; + + for (i = 0; i < dws->num_cs; i++) { + int cs_gpio = of_get_named_gpio(pdev->dev.of_node, + "cs-gpios", i); + + if (cs_gpio == -EPROBE_DEFER) { + ret = cs_gpio; + goto out; + } + + if (gpio_is_valid(cs_gpio)) { + ret = devm_gpio_request(&pdev->dev, cs_gpio, + dev_name(&pdev->dev)); + if (ret) + goto out; + } + } + } + + ret = dw_spi_add_host(&pdev->dev, dws); + if (ret) + goto out; + + platform_set_drvdata(pdev, dwsmmio); + return 0; + +out: + clk_disable_unprepare(dwsmmio->clk); + return ret; +} + +static int dw_spi_mmio_remove(struct platform_device *pdev) +{ + struct dw_spi_mmio *dwsmmio = platform_get_drvdata(pdev); + + clk_disable_unprepare(dwsmmio->clk); + dw_spi_remove_host(&dwsmmio->dws); + + return 0; +} + +static const struct of_device_id dw_spi_mmio_of_match[] = { + { .compatible = "snps,dw-apb-ssi", }, + { /* end of table */} +}; +MODULE_DEVICE_TABLE(of, dw_spi_mmio_of_match); + +static struct platform_driver dw_spi_mmio_driver = { + .probe = dw_spi_mmio_probe, + .remove = dw_spi_mmio_remove, + .driver = { + .name = DRIVER_NAME, + .of_match_table = dw_spi_mmio_of_match, + }, +}; +module_platform_driver(dw_spi_mmio_driver); + +MODULE_AUTHOR("Jean-Hugues Deschenes <jean-hugues.deschenes@octasic.com>"); +MODULE_DESCRIPTION("Memory-mapped I/O interface driver for DW SPI Core"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/spi/spi-dw-pci.c b/drivers/spi/spi-dw-pci.c new file mode 100644 index 000000000..6d331e0db --- /dev/null +++ b/drivers/spi/spi-dw-pci.c @@ -0,0 +1,164 @@ +/* + * PCI interface driver for DW SPI Core + * + * Copyright (c) 2009, 2014 Intel Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + */ + +#include <linux/interrupt.h> +#include <linux/pci.h> +#include <linux/slab.h> +#include <linux/spi/spi.h> +#include <linux/module.h> + +#include "spi-dw.h" + +#define DRIVER_NAME "dw_spi_pci" + +struct dw_spi_pci { + struct pci_dev *pdev; + struct dw_spi dws; +}; + +struct spi_pci_desc { + int (*setup)(struct dw_spi *); + u16 num_cs; + u16 bus_num; +}; + +static struct spi_pci_desc spi_pci_mid_desc_1 = { + .setup = dw_spi_mid_init, + .num_cs = 5, + .bus_num = 0, +}; + +static struct spi_pci_desc spi_pci_mid_desc_2 = { + .setup = dw_spi_mid_init, + .num_cs = 2, + .bus_num = 1, +}; + +static int spi_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent) +{ + struct dw_spi_pci *dwpci; + struct dw_spi *dws; + struct spi_pci_desc *desc = (struct spi_pci_desc *)ent->driver_data; + int pci_bar = 0; + int ret; + + ret = pcim_enable_device(pdev); + if (ret) + return ret; + + dwpci = devm_kzalloc(&pdev->dev, sizeof(struct dw_spi_pci), + GFP_KERNEL); + if (!dwpci) + return -ENOMEM; + + dwpci->pdev = pdev; + dws = &dwpci->dws; + + /* Get basic io resource and map it */ + dws->paddr = pci_resource_start(pdev, pci_bar); + + ret = pcim_iomap_regions(pdev, 1 << pci_bar, pci_name(pdev)); + if (ret) + return ret; + + dws->regs = pcim_iomap_table(pdev)[pci_bar]; + + dws->irq = pdev->irq; + + /* + * Specific handling for paltforms, like dma setup, + * clock rate, FIFO depth. + */ + if (desc) { + dws->num_cs = desc->num_cs; + dws->bus_num = desc->bus_num; + + if (desc->setup) { + ret = desc->setup(dws); + if (ret) + return ret; + } + } else { + return -ENODEV; + } + + ret = dw_spi_add_host(&pdev->dev, dws); + if (ret) + return ret; + + /* PCI hook and SPI hook use the same drv data */ + pci_set_drvdata(pdev, dwpci); + + dev_info(&pdev->dev, "found PCI SPI controller(ID: %04x:%04x)\n", + pdev->vendor, pdev->device); + + return 0; +} + +static void spi_pci_remove(struct pci_dev *pdev) +{ + struct dw_spi_pci *dwpci = pci_get_drvdata(pdev); + + dw_spi_remove_host(&dwpci->dws); +} + +#ifdef CONFIG_PM_SLEEP +static int spi_suspend(struct device *dev) +{ + struct pci_dev *pdev = to_pci_dev(dev); + struct dw_spi_pci *dwpci = pci_get_drvdata(pdev); + + return dw_spi_suspend_host(&dwpci->dws); +} + +static int spi_resume(struct device *dev) +{ + struct pci_dev *pdev = to_pci_dev(dev); + struct dw_spi_pci *dwpci = pci_get_drvdata(pdev); + + return dw_spi_resume_host(&dwpci->dws); +} +#endif + +static SIMPLE_DEV_PM_OPS(dw_spi_pm_ops, spi_suspend, spi_resume); + +static const struct pci_device_id pci_ids[] = { + /* Intel MID platform SPI controller 0 */ + /* + * The access to the device 8086:0801 is disabled by HW, since it's + * exclusively used by SCU to communicate with MSIC. + */ + /* Intel MID platform SPI controller 1 */ + { PCI_VDEVICE(INTEL, 0x0800), (kernel_ulong_t)&spi_pci_mid_desc_1}, + /* Intel MID platform SPI controller 2 */ + { PCI_VDEVICE(INTEL, 0x0812), (kernel_ulong_t)&spi_pci_mid_desc_2}, + {}, +}; + +static struct pci_driver dw_spi_driver = { + .name = DRIVER_NAME, + .id_table = pci_ids, + .probe = spi_pci_probe, + .remove = spi_pci_remove, + .driver = { + .pm = &dw_spi_pm_ops, + }, +}; + +module_pci_driver(dw_spi_driver); + +MODULE_AUTHOR("Feng Tang <feng.tang@intel.com>"); +MODULE_DESCRIPTION("PCI interface driver for DW SPI Core"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/spi/spi-dw.c b/drivers/spi/spi-dw.c new file mode 100644 index 000000000..8d67d03c7 --- /dev/null +++ b/drivers/spi/spi-dw.c @@ -0,0 +1,623 @@ +/* + * Designware SPI core controller driver (refer pxa2xx_spi.c) + * + * Copyright (c) 2009, Intel Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + */ + +#include <linux/dma-mapping.h> +#include <linux/interrupt.h> +#include <linux/module.h> +#include <linux/highmem.h> +#include <linux/delay.h> +#include <linux/slab.h> +#include <linux/spi/spi.h> +#include <linux/gpio.h> + +#include "spi-dw.h" + +#ifdef CONFIG_DEBUG_FS +#include <linux/debugfs.h> +#endif + +/* Slave spi_dev related */ +struct chip_data { + u16 cr0; + u8 cs; /* chip select pin */ + u8 n_bytes; /* current is a 1/2/4 byte op */ + u8 tmode; /* TR/TO/RO/EEPROM */ + u8 type; /* SPI/SSP/MicroWire */ + + u8 poll_mode; /* 1 means use poll mode */ + + u32 dma_width; + u32 rx_threshold; + u32 tx_threshold; + u8 enable_dma; + u8 bits_per_word; + u16 clk_div; /* baud rate divider */ + u32 speed_hz; /* baud rate */ + void (*cs_control)(u32 command); +}; + +#ifdef CONFIG_DEBUG_FS +#define SPI_REGS_BUFSIZE 1024 +static ssize_t dw_spi_show_regs(struct file *file, char __user *user_buf, + size_t count, loff_t *ppos) +{ + struct dw_spi *dws = file->private_data; + char *buf; + u32 len = 0; + ssize_t ret; + + buf = kzalloc(SPI_REGS_BUFSIZE, GFP_KERNEL); + if (!buf) + return 0; + + len += snprintf(buf + len, SPI_REGS_BUFSIZE - len, + "%s registers:\n", dev_name(&dws->master->dev)); + len += snprintf(buf + len, SPI_REGS_BUFSIZE - len, + "=================================\n"); + len += snprintf(buf + len, SPI_REGS_BUFSIZE - len, + "CTRL0: \t\t0x%08x\n", dw_readl(dws, DW_SPI_CTRL0)); + len += snprintf(buf + len, SPI_REGS_BUFSIZE - len, + "CTRL1: \t\t0x%08x\n", dw_readl(dws, DW_SPI_CTRL1)); + len += snprintf(buf + len, SPI_REGS_BUFSIZE - len, + "SSIENR: \t0x%08x\n", dw_readl(dws, DW_SPI_SSIENR)); + len += snprintf(buf + len, SPI_REGS_BUFSIZE - len, + "SER: \t\t0x%08x\n", dw_readl(dws, DW_SPI_SER)); + len += snprintf(buf + len, SPI_REGS_BUFSIZE - len, + "BAUDR: \t\t0x%08x\n", dw_readl(dws, DW_SPI_BAUDR)); + len += snprintf(buf + len, SPI_REGS_BUFSIZE - len, + "TXFTLR: \t0x%08x\n", dw_readl(dws, DW_SPI_TXFLTR)); + len += snprintf(buf + len, SPI_REGS_BUFSIZE - len, + "RXFTLR: \t0x%08x\n", dw_readl(dws, DW_SPI_RXFLTR)); + len += snprintf(buf + len, SPI_REGS_BUFSIZE - len, + "TXFLR: \t\t0x%08x\n", dw_readl(dws, DW_SPI_TXFLR)); + len += snprintf(buf + len, SPI_REGS_BUFSIZE - len, + "RXFLR: \t\t0x%08x\n", dw_readl(dws, DW_SPI_RXFLR)); + len += snprintf(buf + len, SPI_REGS_BUFSIZE - len, + "SR: \t\t0x%08x\n", dw_readl(dws, DW_SPI_SR)); + len += snprintf(buf + len, SPI_REGS_BUFSIZE - len, + "IMR: \t\t0x%08x\n", dw_readl(dws, DW_SPI_IMR)); + len += snprintf(buf + len, SPI_REGS_BUFSIZE - len, + "ISR: \t\t0x%08x\n", dw_readl(dws, DW_SPI_ISR)); + len += snprintf(buf + len, SPI_REGS_BUFSIZE - len, + "DMACR: \t\t0x%08x\n", dw_readl(dws, DW_SPI_DMACR)); + len += snprintf(buf + len, SPI_REGS_BUFSIZE - len, + "DMATDLR: \t0x%08x\n", dw_readl(dws, DW_SPI_DMATDLR)); + len += snprintf(buf + len, SPI_REGS_BUFSIZE - len, + "DMARDLR: \t0x%08x\n", dw_readl(dws, DW_SPI_DMARDLR)); + len += snprintf(buf + len, SPI_REGS_BUFSIZE - len, + "=================================\n"); + + ret = simple_read_from_buffer(user_buf, count, ppos, buf, len); + kfree(buf); + return ret; +} + +static const struct file_operations dw_spi_regs_ops = { + .owner = THIS_MODULE, + .open = simple_open, + .read = dw_spi_show_regs, + .llseek = default_llseek, +}; + +static int dw_spi_debugfs_init(struct dw_spi *dws) +{ + dws->debugfs = debugfs_create_dir("dw_spi", NULL); + if (!dws->debugfs) + return -ENOMEM; + + debugfs_create_file("registers", S_IFREG | S_IRUGO, + dws->debugfs, (void *)dws, &dw_spi_regs_ops); + return 0; +} + +static void dw_spi_debugfs_remove(struct dw_spi *dws) +{ + debugfs_remove_recursive(dws->debugfs); +} + +#else +static inline int dw_spi_debugfs_init(struct dw_spi *dws) +{ + return 0; +} + +static inline void dw_spi_debugfs_remove(struct dw_spi *dws) +{ +} +#endif /* CONFIG_DEBUG_FS */ + +static void dw_spi_set_cs(struct spi_device *spi, bool enable) +{ + struct dw_spi *dws = spi_master_get_devdata(spi->master); + struct chip_data *chip = spi_get_ctldata(spi); + + /* Chip select logic is inverted from spi_set_cs() */ + if (chip && chip->cs_control) + chip->cs_control(!enable); + + if (!enable) + dw_writel(dws, DW_SPI_SER, BIT(spi->chip_select)); +} + +/* Return the max entries we can fill into tx fifo */ +static inline u32 tx_max(struct dw_spi *dws) +{ + u32 tx_left, tx_room, rxtx_gap; + + tx_left = (dws->tx_end - dws->tx) / dws->n_bytes; + tx_room = dws->fifo_len - dw_readl(dws, DW_SPI_TXFLR); + + /* + * Another concern is about the tx/rx mismatch, we + * though to use (dws->fifo_len - rxflr - txflr) as + * one maximum value for tx, but it doesn't cover the + * data which is out of tx/rx fifo and inside the + * shift registers. So a control from sw point of + * view is taken. + */ + rxtx_gap = ((dws->rx_end - dws->rx) - (dws->tx_end - dws->tx)) + / dws->n_bytes; + + return min3(tx_left, tx_room, (u32) (dws->fifo_len - rxtx_gap)); +} + +/* Return the max entries we should read out of rx fifo */ +static inline u32 rx_max(struct dw_spi *dws) +{ + u32 rx_left = (dws->rx_end - dws->rx) / dws->n_bytes; + + return min_t(u32, rx_left, dw_readl(dws, DW_SPI_RXFLR)); +} + +static void dw_writer(struct dw_spi *dws) +{ + u32 max = tx_max(dws); + u16 txw = 0; + + while (max--) { + /* Set the tx word if the transfer's original "tx" is not null */ + if (dws->tx_end - dws->len) { + if (dws->n_bytes == 1) + txw = *(u8 *)(dws->tx); + else + txw = *(u16 *)(dws->tx); + } + dw_writel(dws, DW_SPI_DR, txw); + dws->tx += dws->n_bytes; + } +} + +static void dw_reader(struct dw_spi *dws) +{ + u32 max = rx_max(dws); + u16 rxw; + + while (max--) { + rxw = dw_readl(dws, DW_SPI_DR); + /* Care rx only if the transfer's original "rx" is not null */ + if (dws->rx_end - dws->len) { + if (dws->n_bytes == 1) + *(u8 *)(dws->rx) = rxw; + else + *(u16 *)(dws->rx) = rxw; + } + dws->rx += dws->n_bytes; + } +} + +static void int_error_stop(struct dw_spi *dws, const char *msg) +{ + spi_reset_chip(dws); + + dev_err(&dws->master->dev, "%s\n", msg); + dws->master->cur_msg->status = -EIO; + spi_finalize_current_transfer(dws->master); +} + +static irqreturn_t interrupt_transfer(struct dw_spi *dws) +{ + u16 irq_status = dw_readl(dws, DW_SPI_ISR); + + /* Error handling */ + if (irq_status & (SPI_INT_TXOI | SPI_INT_RXOI | SPI_INT_RXUI)) { + dw_readl(dws, DW_SPI_ICR); + int_error_stop(dws, "interrupt_transfer: fifo overrun/underrun"); + return IRQ_HANDLED; + } + + dw_reader(dws); + if (dws->rx_end == dws->rx) { + spi_mask_intr(dws, SPI_INT_TXEI); + spi_finalize_current_transfer(dws->master); + return IRQ_HANDLED; + } + if (irq_status & SPI_INT_TXEI) { + spi_mask_intr(dws, SPI_INT_TXEI); + dw_writer(dws); + /* Enable TX irq always, it will be disabled when RX finished */ + spi_umask_intr(dws, SPI_INT_TXEI); + } + + return IRQ_HANDLED; +} + +static irqreturn_t dw_spi_irq(int irq, void *dev_id) +{ + struct spi_master *master = dev_id; + struct dw_spi *dws = spi_master_get_devdata(master); + u16 irq_status = dw_readl(dws, DW_SPI_ISR) & 0x3f; + + if (!irq_status) + return IRQ_NONE; + + if (!master->cur_msg) { + spi_mask_intr(dws, SPI_INT_TXEI); + return IRQ_HANDLED; + } + + return dws->transfer_handler(dws); +} + +/* Must be called inside pump_transfers() */ +static int poll_transfer(struct dw_spi *dws) +{ + do { + dw_writer(dws); + dw_reader(dws); + cpu_relax(); + } while (dws->rx_end > dws->rx); + + return 0; +} + +static int dw_spi_transfer_one(struct spi_master *master, + struct spi_device *spi, struct spi_transfer *transfer) +{ + struct dw_spi *dws = spi_master_get_devdata(master); + struct chip_data *chip = spi_get_ctldata(spi); + u8 imask = 0; + u16 txlevel = 0; + u16 clk_div = 0; + u32 speed = 0; + u32 cr0 = 0; + int ret; + + dws->dma_mapped = 0; + dws->n_bytes = chip->n_bytes; + dws->dma_width = chip->dma_width; + + dws->tx = (void *)transfer->tx_buf; + dws->tx_end = dws->tx + transfer->len; + dws->rx = transfer->rx_buf; + dws->rx_end = dws->rx + transfer->len; + dws->len = transfer->len; + + spi_enable_chip(dws, 0); + + cr0 = chip->cr0; + + /* Handle per transfer options for bpw and speed */ + if (transfer->speed_hz) { + speed = chip->speed_hz; + + if ((transfer->speed_hz != speed) || !chip->clk_div) { + speed = transfer->speed_hz; + + /* clk_div doesn't support odd number */ + clk_div = (dws->max_freq / speed + 1) & 0xfffe; + + chip->speed_hz = speed; + chip->clk_div = clk_div; + + spi_set_clk(dws, chip->clk_div); + } + } + if (transfer->bits_per_word) { + if (transfer->bits_per_word == 8) { + dws->n_bytes = 1; + dws->dma_width = 1; + } else if (transfer->bits_per_word == 16) { + dws->n_bytes = 2; + dws->dma_width = 2; + } + cr0 = (transfer->bits_per_word - 1) + | (chip->type << SPI_FRF_OFFSET) + | (spi->mode << SPI_MODE_OFFSET) + | (chip->tmode << SPI_TMOD_OFFSET); + } + + /* + * Adjust transfer mode if necessary. Requires platform dependent + * chipselect mechanism. + */ + if (chip->cs_control) { + if (dws->rx && dws->tx) + chip->tmode = SPI_TMOD_TR; + else if (dws->rx) + chip->tmode = SPI_TMOD_RO; + else + chip->tmode = SPI_TMOD_TO; + + cr0 &= ~SPI_TMOD_MASK; + cr0 |= (chip->tmode << SPI_TMOD_OFFSET); + } + + dw_writel(dws, DW_SPI_CTRL0, cr0); + + /* Check if current transfer is a DMA transaction */ + if (master->can_dma && master->can_dma(master, spi, transfer)) + dws->dma_mapped = master->cur_msg_mapped; + + /* For poll mode just disable all interrupts */ + spi_mask_intr(dws, 0xff); + + /* + * Interrupt mode + * we only need set the TXEI IRQ, as TX/RX always happen syncronizely + */ + if (dws->dma_mapped) { + ret = dws->dma_ops->dma_setup(dws, transfer); + if (ret < 0) { + spi_enable_chip(dws, 1); + return ret; + } + } else if (!chip->poll_mode) { + txlevel = min_t(u16, dws->fifo_len / 2, dws->len / dws->n_bytes); + dw_writel(dws, DW_SPI_TXFLTR, txlevel); + + /* Set the interrupt mask */ + imask |= SPI_INT_TXEI | SPI_INT_TXOI | + SPI_INT_RXUI | SPI_INT_RXOI; + spi_umask_intr(dws, imask); + + dws->transfer_handler = interrupt_transfer; + } + + spi_enable_chip(dws, 1); + + if (dws->dma_mapped) { + ret = dws->dma_ops->dma_transfer(dws, transfer); + if (ret < 0) + return ret; + } + + if (chip->poll_mode) + return poll_transfer(dws); + + return 1; +} + +static void dw_spi_handle_err(struct spi_master *master, + struct spi_message *msg) +{ + struct dw_spi *dws = spi_master_get_devdata(master); + + if (dws->dma_mapped) + dws->dma_ops->dma_stop(dws); + + spi_reset_chip(dws); +} + +/* This may be called twice for each spi dev */ +static int dw_spi_setup(struct spi_device *spi) +{ + struct dw_spi_chip *chip_info = NULL; + struct chip_data *chip; + int ret; + + /* Only alloc on first setup */ + chip = spi_get_ctldata(spi); + if (!chip) { + chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL); + if (!chip) + return -ENOMEM; + spi_set_ctldata(spi, chip); + } + + /* + * Protocol drivers may change the chip settings, so... + * if chip_info exists, use it + */ + chip_info = spi->controller_data; + + /* chip_info doesn't always exist */ + if (chip_info) { + if (chip_info->cs_control) + chip->cs_control = chip_info->cs_control; + + chip->poll_mode = chip_info->poll_mode; + chip->type = chip_info->type; + + chip->rx_threshold = 0; + chip->tx_threshold = 0; + } + + if (spi->bits_per_word == 8) { + chip->n_bytes = 1; + chip->dma_width = 1; + } else if (spi->bits_per_word == 16) { + chip->n_bytes = 2; + chip->dma_width = 2; + } + chip->bits_per_word = spi->bits_per_word; + + if (!spi->max_speed_hz) { + dev_err(&spi->dev, "No max speed HZ parameter\n"); + return -EINVAL; + } + + chip->tmode = 0; /* Tx & Rx */ + /* Default SPI mode is SCPOL = 0, SCPH = 0 */ + chip->cr0 = (chip->bits_per_word - 1) + | (chip->type << SPI_FRF_OFFSET) + | (spi->mode << SPI_MODE_OFFSET) + | (chip->tmode << SPI_TMOD_OFFSET); + + if (spi->mode & SPI_LOOP) + chip->cr0 |= 1 << SPI_SRL_OFFSET; + + if (gpio_is_valid(spi->cs_gpio)) { + ret = gpio_direction_output(spi->cs_gpio, + !(spi->mode & SPI_CS_HIGH)); + if (ret) + return ret; + } + + return 0; +} + +static void dw_spi_cleanup(struct spi_device *spi) +{ + struct chip_data *chip = spi_get_ctldata(spi); + + kfree(chip); + spi_set_ctldata(spi, NULL); +} + +/* Restart the controller, disable all interrupts, clean rx fifo */ +static void spi_hw_init(struct device *dev, struct dw_spi *dws) +{ + spi_reset_chip(dws); + + /* + * Try to detect the FIFO depth if not set by interface driver, + * the depth could be from 2 to 256 from HW spec + */ + if (!dws->fifo_len) { + u32 fifo; + + for (fifo = 1; fifo < 256; fifo++) { + dw_writel(dws, DW_SPI_TXFLTR, fifo); + if (fifo != dw_readl(dws, DW_SPI_TXFLTR)) + break; + } + dw_writel(dws, DW_SPI_TXFLTR, 0); + + dws->fifo_len = (fifo == 1) ? 0 : fifo; + dev_dbg(dev, "Detected FIFO size: %u bytes\n", dws->fifo_len); + } +} + +int dw_spi_add_host(struct device *dev, struct dw_spi *dws) +{ + struct spi_master *master; + int ret; + + BUG_ON(dws == NULL); + + master = spi_alloc_master(dev, 0); + if (!master) + return -ENOMEM; + + dws->master = master; + dws->type = SSI_MOTO_SPI; + dws->dma_inited = 0; + dws->dma_addr = (dma_addr_t)(dws->paddr + 0x60); + snprintf(dws->name, sizeof(dws->name), "dw_spi%d", dws->bus_num); + + ret = devm_request_irq(dev, dws->irq, dw_spi_irq, IRQF_SHARED, + dws->name, master); + if (ret < 0) { + dev_err(&master->dev, "can not get IRQ\n"); + goto err_free_master; + } + + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LOOP; + master->bits_per_word_mask = SPI_BPW_MASK(8) | SPI_BPW_MASK(16); + master->bus_num = dws->bus_num; + master->num_chipselect = dws->num_cs; + master->setup = dw_spi_setup; + master->cleanup = dw_spi_cleanup; + master->set_cs = dw_spi_set_cs; + master->transfer_one = dw_spi_transfer_one; + master->handle_err = dw_spi_handle_err; + master->max_speed_hz = dws->max_freq; + master->dev.of_node = dev->of_node; + + /* Basic HW init */ + spi_hw_init(dev, dws); + + if (dws->dma_ops && dws->dma_ops->dma_init) { + ret = dws->dma_ops->dma_init(dws); + if (ret) { + dev_warn(dev, "DMA init failed\n"); + dws->dma_inited = 0; + } else { + master->can_dma = dws->dma_ops->can_dma; + } + } + + spi_master_set_devdata(master, dws); + ret = devm_spi_register_master(dev, master); + if (ret) { + dev_err(&master->dev, "problem registering spi master\n"); + goto err_dma_exit; + } + + dw_spi_debugfs_init(dws); + return 0; + +err_dma_exit: + if (dws->dma_ops && dws->dma_ops->dma_exit) + dws->dma_ops->dma_exit(dws); + spi_enable_chip(dws, 0); +err_free_master: + spi_master_put(master); + return ret; +} +EXPORT_SYMBOL_GPL(dw_spi_add_host); + +void dw_spi_remove_host(struct dw_spi *dws) +{ + if (!dws) + return; + dw_spi_debugfs_remove(dws); + + if (dws->dma_ops && dws->dma_ops->dma_exit) + dws->dma_ops->dma_exit(dws); + spi_enable_chip(dws, 0); + /* Disable clk */ + spi_set_clk(dws, 0); +} +EXPORT_SYMBOL_GPL(dw_spi_remove_host); + +int dw_spi_suspend_host(struct dw_spi *dws) +{ + int ret = 0; + + ret = spi_master_suspend(dws->master); + if (ret) + return ret; + spi_enable_chip(dws, 0); + spi_set_clk(dws, 0); + return ret; +} +EXPORT_SYMBOL_GPL(dw_spi_suspend_host); + +int dw_spi_resume_host(struct dw_spi *dws) +{ + int ret; + + spi_hw_init(&dws->master->dev, dws); + ret = spi_master_resume(dws->master); + if (ret) + dev_err(&dws->master->dev, "fail to start queue (%d)\n", ret); + return ret; +} +EXPORT_SYMBOL_GPL(dw_spi_resume_host); + +MODULE_AUTHOR("Feng Tang <feng.tang@intel.com>"); +MODULE_DESCRIPTION("Driver for DesignWare SPI controller core"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/spi/spi-dw.h b/drivers/spi/spi-dw.h new file mode 100644 index 000000000..6c91391c1 --- /dev/null +++ b/drivers/spi/spi-dw.h @@ -0,0 +1,212 @@ +#ifndef DW_SPI_HEADER_H +#define DW_SPI_HEADER_H + +#include <linux/io.h> +#include <linux/scatterlist.h> +#include <linux/gpio.h> + +/* Register offsets */ +#define DW_SPI_CTRL0 0x00 +#define DW_SPI_CTRL1 0x04 +#define DW_SPI_SSIENR 0x08 +#define DW_SPI_MWCR 0x0c +#define DW_SPI_SER 0x10 +#define DW_SPI_BAUDR 0x14 +#define DW_SPI_TXFLTR 0x18 +#define DW_SPI_RXFLTR 0x1c +#define DW_SPI_TXFLR 0x20 +#define DW_SPI_RXFLR 0x24 +#define DW_SPI_SR 0x28 +#define DW_SPI_IMR 0x2c +#define DW_SPI_ISR 0x30 +#define DW_SPI_RISR 0x34 +#define DW_SPI_TXOICR 0x38 +#define DW_SPI_RXOICR 0x3c +#define DW_SPI_RXUICR 0x40 +#define DW_SPI_MSTICR 0x44 +#define DW_SPI_ICR 0x48 +#define DW_SPI_DMACR 0x4c +#define DW_SPI_DMATDLR 0x50 +#define DW_SPI_DMARDLR 0x54 +#define DW_SPI_IDR 0x58 +#define DW_SPI_VERSION 0x5c +#define DW_SPI_DR 0x60 + +/* Bit fields in CTRLR0 */ +#define SPI_DFS_OFFSET 0 + +#define SPI_FRF_OFFSET 4 +#define SPI_FRF_SPI 0x0 +#define SPI_FRF_SSP 0x1 +#define SPI_FRF_MICROWIRE 0x2 +#define SPI_FRF_RESV 0x3 + +#define SPI_MODE_OFFSET 6 +#define SPI_SCPH_OFFSET 6 +#define SPI_SCOL_OFFSET 7 + +#define SPI_TMOD_OFFSET 8 +#define SPI_TMOD_MASK (0x3 << SPI_TMOD_OFFSET) +#define SPI_TMOD_TR 0x0 /* xmit & recv */ +#define SPI_TMOD_TO 0x1 /* xmit only */ +#define SPI_TMOD_RO 0x2 /* recv only */ +#define SPI_TMOD_EPROMREAD 0x3 /* eeprom read mode */ + +#define SPI_SLVOE_OFFSET 10 +#define SPI_SRL_OFFSET 11 +#define SPI_CFS_OFFSET 12 + +/* Bit fields in SR, 7 bits */ +#define SR_MASK 0x7f /* cover 7 bits */ +#define SR_BUSY (1 << 0) +#define SR_TF_NOT_FULL (1 << 1) +#define SR_TF_EMPT (1 << 2) +#define SR_RF_NOT_EMPT (1 << 3) +#define SR_RF_FULL (1 << 4) +#define SR_TX_ERR (1 << 5) +#define SR_DCOL (1 << 6) + +/* Bit fields in ISR, IMR, RISR, 7 bits */ +#define SPI_INT_TXEI (1 << 0) +#define SPI_INT_TXOI (1 << 1) +#define SPI_INT_RXUI (1 << 2) +#define SPI_INT_RXOI (1 << 3) +#define SPI_INT_RXFI (1 << 4) +#define SPI_INT_MSTI (1 << 5) + +/* Bit fields in DMACR */ +#define SPI_DMA_RDMAE (1 << 0) +#define SPI_DMA_TDMAE (1 << 1) + +/* TX RX interrupt level threshold, max can be 256 */ +#define SPI_INT_THRESHOLD 32 + +enum dw_ssi_type { + SSI_MOTO_SPI = 0, + SSI_TI_SSP, + SSI_NS_MICROWIRE, +}; + +struct dw_spi; +struct dw_spi_dma_ops { + int (*dma_init)(struct dw_spi *dws); + void (*dma_exit)(struct dw_spi *dws); + int (*dma_setup)(struct dw_spi *dws, struct spi_transfer *xfer); + bool (*can_dma)(struct spi_master *master, struct spi_device *spi, + struct spi_transfer *xfer); + int (*dma_transfer)(struct dw_spi *dws, struct spi_transfer *xfer); + void (*dma_stop)(struct dw_spi *dws); +}; + +struct dw_spi { + struct spi_master *master; + enum dw_ssi_type type; + char name[16]; + + void __iomem *regs; + unsigned long paddr; + int irq; + u32 fifo_len; /* depth of the FIFO buffer */ + u32 max_freq; /* max bus freq supported */ + + u16 bus_num; + u16 num_cs; /* supported slave numbers */ + + /* Current message transfer state info */ + size_t len; + void *tx; + void *tx_end; + void *rx; + void *rx_end; + int dma_mapped; + u8 n_bytes; /* current is a 1/2 bytes op */ + u32 dma_width; + irqreturn_t (*transfer_handler)(struct dw_spi *dws); + + /* DMA info */ + int dma_inited; + struct dma_chan *txchan; + struct dma_chan *rxchan; + unsigned long dma_chan_busy; + dma_addr_t dma_addr; /* phy address of the Data register */ + struct dw_spi_dma_ops *dma_ops; + void *dma_tx; + void *dma_rx; + + /* Bus interface info */ + void *priv; +#ifdef CONFIG_DEBUG_FS + struct dentry *debugfs; +#endif +}; + +static inline u32 dw_readl(struct dw_spi *dws, u32 offset) +{ + return __raw_readl(dws->regs + offset); +} + +static inline void dw_writel(struct dw_spi *dws, u32 offset, u32 val) +{ + __raw_writel(val, dws->regs + offset); +} + +static inline void spi_enable_chip(struct dw_spi *dws, int enable) +{ + dw_writel(dws, DW_SPI_SSIENR, (enable ? 1 : 0)); +} + +static inline void spi_set_clk(struct dw_spi *dws, u16 div) +{ + dw_writel(dws, DW_SPI_BAUDR, div); +} + +/* Disable IRQ bits */ +static inline void spi_mask_intr(struct dw_spi *dws, u32 mask) +{ + u32 new_mask; + + new_mask = dw_readl(dws, DW_SPI_IMR) & ~mask; + dw_writel(dws, DW_SPI_IMR, new_mask); +} + +/* Enable IRQ bits */ +static inline void spi_umask_intr(struct dw_spi *dws, u32 mask) +{ + u32 new_mask; + + new_mask = dw_readl(dws, DW_SPI_IMR) | mask; + dw_writel(dws, DW_SPI_IMR, new_mask); +} + +/* + * This does disable the SPI controller, interrupts, and re-enable the + * controller back. Transmit and receive FIFO buffers are cleared when the + * device is disabled. + */ +static inline void spi_reset_chip(struct dw_spi *dws) +{ + spi_enable_chip(dws, 0); + spi_mask_intr(dws, 0xff); + spi_enable_chip(dws, 1); +} + +/* + * Each SPI slave device to work with dw_api controller should + * has such a structure claiming its working mode (poll or PIO/DMA), + * which can be save in the "controller_data" member of the + * struct spi_device. + */ +struct dw_spi_chip { + u8 poll_mode; /* 1 for controller polling mode */ + u8 type; /* SPI/SSP/MicroWire */ + void (*cs_control)(u32 command); +}; + +extern int dw_spi_add_host(struct device *dev, struct dw_spi *dws); +extern void dw_spi_remove_host(struct dw_spi *dws); +extern int dw_spi_suspend_host(struct dw_spi *dws); +extern int dw_spi_resume_host(struct dw_spi *dws); + +/* platform related setup */ +extern int dw_spi_mid_init(struct dw_spi *dws); /* Intel MID platforms */ +#endif /* DW_SPI_HEADER_H */ diff --git a/drivers/spi/spi-efm32.c b/drivers/spi/spi-efm32.c new file mode 100644 index 000000000..065fe8744 --- /dev/null +++ b/drivers/spi/spi-efm32.c @@ -0,0 +1,505 @@ +/* + * Copyright (C) 2012-2013 Uwe Kleine-Koenig for Pengutronix + * + * This program is free software; you can redistribute it and/or modify it under + * the terms of the GNU General Public License version 2 as published by the + * Free Software Foundation. + */ +#include <linux/kernel.h> +#include <linux/io.h> +#include <linux/spi/spi.h> +#include <linux/spi/spi_bitbang.h> +#include <linux/gpio.h> +#include <linux/interrupt.h> +#include <linux/platform_device.h> +#include <linux/clk.h> +#include <linux/err.h> +#include <linux/module.h> +#include <linux/of_gpio.h> +#include <linux/platform_data/efm32-spi.h> + +#define DRIVER_NAME "efm32-spi" + +#define MASK_VAL(mask, val) ((val << __ffs(mask)) & mask) + +#define REG_CTRL 0x00 +#define REG_CTRL_SYNC 0x0001 +#define REG_CTRL_CLKPOL 0x0100 +#define REG_CTRL_CLKPHA 0x0200 +#define REG_CTRL_MSBF 0x0400 +#define REG_CTRL_TXBIL 0x1000 + +#define REG_FRAME 0x04 +#define REG_FRAME_DATABITS__MASK 0x000f +#define REG_FRAME_DATABITS(n) ((n) - 3) + +#define REG_CMD 0x0c +#define REG_CMD_RXEN 0x0001 +#define REG_CMD_RXDIS 0x0002 +#define REG_CMD_TXEN 0x0004 +#define REG_CMD_TXDIS 0x0008 +#define REG_CMD_MASTEREN 0x0010 + +#define REG_STATUS 0x10 +#define REG_STATUS_TXENS 0x0002 +#define REG_STATUS_TXC 0x0020 +#define REG_STATUS_TXBL 0x0040 +#define REG_STATUS_RXDATAV 0x0080 + +#define REG_CLKDIV 0x14 + +#define REG_RXDATAX 0x18 +#define REG_RXDATAX_RXDATA__MASK 0x01ff +#define REG_RXDATAX_PERR 0x4000 +#define REG_RXDATAX_FERR 0x8000 + +#define REG_TXDATA 0x34 + +#define REG_IF 0x40 +#define REG_IF_TXBL 0x0002 +#define REG_IF_RXDATAV 0x0004 + +#define REG_IFS 0x44 +#define REG_IFC 0x48 +#define REG_IEN 0x4c + +#define REG_ROUTE 0x54 +#define REG_ROUTE_RXPEN 0x0001 +#define REG_ROUTE_TXPEN 0x0002 +#define REG_ROUTE_CLKPEN 0x0008 +#define REG_ROUTE_LOCATION__MASK 0x0700 +#define REG_ROUTE_LOCATION(n) MASK_VAL(REG_ROUTE_LOCATION__MASK, (n)) + +struct efm32_spi_ddata { + struct spi_bitbang bitbang; + + spinlock_t lock; + + struct clk *clk; + void __iomem *base; + unsigned int rxirq, txirq; + struct efm32_spi_pdata pdata; + + /* irq data */ + struct completion done; + const u8 *tx_buf; + u8 *rx_buf; + unsigned tx_len, rx_len; + + /* chip selects */ + unsigned csgpio[]; +}; + +#define ddata_to_dev(ddata) (&(ddata->bitbang.master->dev)) +#define efm32_spi_vdbg(ddata, format, arg...) \ + dev_vdbg(ddata_to_dev(ddata), format, ##arg) + +static void efm32_spi_write32(struct efm32_spi_ddata *ddata, + u32 value, unsigned offset) +{ + writel_relaxed(value, ddata->base + offset); +} + +static u32 efm32_spi_read32(struct efm32_spi_ddata *ddata, unsigned offset) +{ + return readl_relaxed(ddata->base + offset); +} + +static void efm32_spi_chipselect(struct spi_device *spi, int is_on) +{ + struct efm32_spi_ddata *ddata = spi_master_get_devdata(spi->master); + int value = !(spi->mode & SPI_CS_HIGH) == !(is_on == BITBANG_CS_ACTIVE); + + gpio_set_value(ddata->csgpio[spi->chip_select], value); +} + +static int efm32_spi_setup_transfer(struct spi_device *spi, + struct spi_transfer *t) +{ + struct efm32_spi_ddata *ddata = spi_master_get_devdata(spi->master); + + unsigned bpw = t->bits_per_word ?: spi->bits_per_word; + unsigned speed = t->speed_hz ?: spi->max_speed_hz; + unsigned long clkfreq = clk_get_rate(ddata->clk); + u32 clkdiv; + + efm32_spi_write32(ddata, REG_CTRL_SYNC | REG_CTRL_MSBF | + (spi->mode & SPI_CPHA ? REG_CTRL_CLKPHA : 0) | + (spi->mode & SPI_CPOL ? REG_CTRL_CLKPOL : 0), REG_CTRL); + + efm32_spi_write32(ddata, + REG_FRAME_DATABITS(bpw), REG_FRAME); + + if (2 * speed >= clkfreq) + clkdiv = 0; + else + clkdiv = 64 * (DIV_ROUND_UP(2 * clkfreq, speed) - 4); + + if (clkdiv > (1U << 21)) + return -EINVAL; + + efm32_spi_write32(ddata, clkdiv, REG_CLKDIV); + efm32_spi_write32(ddata, REG_CMD_MASTEREN, REG_CMD); + efm32_spi_write32(ddata, REG_CMD_RXEN | REG_CMD_TXEN, REG_CMD); + + return 0; +} + +static void efm32_spi_tx_u8(struct efm32_spi_ddata *ddata) +{ + u8 val = 0; + + if (ddata->tx_buf) { + val = *ddata->tx_buf; + ddata->tx_buf++; + } + + ddata->tx_len--; + efm32_spi_write32(ddata, val, REG_TXDATA); + efm32_spi_vdbg(ddata, "%s: tx 0x%x\n", __func__, val); +} + +static void efm32_spi_rx_u8(struct efm32_spi_ddata *ddata) +{ + u32 rxdata = efm32_spi_read32(ddata, REG_RXDATAX); + efm32_spi_vdbg(ddata, "%s: rx 0x%x\n", __func__, rxdata); + + if (ddata->rx_buf) { + *ddata->rx_buf = rxdata; + ddata->rx_buf++; + } + + ddata->rx_len--; +} + +static void efm32_spi_filltx(struct efm32_spi_ddata *ddata) +{ + while (ddata->tx_len && + ddata->tx_len + 2 > ddata->rx_len && + efm32_spi_read32(ddata, REG_STATUS) & REG_STATUS_TXBL) { + efm32_spi_tx_u8(ddata); + } +} + +static int efm32_spi_txrx_bufs(struct spi_device *spi, struct spi_transfer *t) +{ + struct efm32_spi_ddata *ddata = spi_master_get_devdata(spi->master); + int ret = -EBUSY; + + spin_lock_irq(&ddata->lock); + + if (ddata->tx_buf || ddata->rx_buf) + goto out_unlock; + + ddata->tx_buf = t->tx_buf; + ddata->rx_buf = t->rx_buf; + ddata->tx_len = ddata->rx_len = + t->len * DIV_ROUND_UP(t->bits_per_word, 8); + + efm32_spi_filltx(ddata); + + reinit_completion(&ddata->done); + + efm32_spi_write32(ddata, REG_IF_TXBL | REG_IF_RXDATAV, REG_IEN); + + spin_unlock_irq(&ddata->lock); + + wait_for_completion(&ddata->done); + + spin_lock_irq(&ddata->lock); + + ret = t->len - max(ddata->tx_len, ddata->rx_len); + + efm32_spi_write32(ddata, 0, REG_IEN); + ddata->tx_buf = ddata->rx_buf = NULL; + +out_unlock: + spin_unlock_irq(&ddata->lock); + + return ret; +} + +static irqreturn_t efm32_spi_rxirq(int irq, void *data) +{ + struct efm32_spi_ddata *ddata = data; + irqreturn_t ret = IRQ_NONE; + + spin_lock(&ddata->lock); + + while (ddata->rx_len > 0 && + efm32_spi_read32(ddata, REG_STATUS) & + REG_STATUS_RXDATAV) { + efm32_spi_rx_u8(ddata); + + ret = IRQ_HANDLED; + } + + if (!ddata->rx_len) { + u32 ien = efm32_spi_read32(ddata, REG_IEN); + + ien &= ~REG_IF_RXDATAV; + + efm32_spi_write32(ddata, ien, REG_IEN); + + complete(&ddata->done); + } + + spin_unlock(&ddata->lock); + + return ret; +} + +static irqreturn_t efm32_spi_txirq(int irq, void *data) +{ + struct efm32_spi_ddata *ddata = data; + + efm32_spi_vdbg(ddata, + "%s: txlen = %u, rxlen = %u, if=0x%08x, stat=0x%08x\n", + __func__, ddata->tx_len, ddata->rx_len, + efm32_spi_read32(ddata, REG_IF), + efm32_spi_read32(ddata, REG_STATUS)); + + spin_lock(&ddata->lock); + + efm32_spi_filltx(ddata); + + efm32_spi_vdbg(ddata, "%s: txlen = %u, rxlen = %u\n", + __func__, ddata->tx_len, ddata->rx_len); + + if (!ddata->tx_len) { + u32 ien = efm32_spi_read32(ddata, REG_IEN); + + ien &= ~REG_IF_TXBL; + + efm32_spi_write32(ddata, ien, REG_IEN); + efm32_spi_vdbg(ddata, "disable TXBL\n"); + } + + spin_unlock(&ddata->lock); + + return IRQ_HANDLED; +} + +static u32 efm32_spi_get_configured_location(struct efm32_spi_ddata *ddata) +{ + u32 reg = efm32_spi_read32(ddata, REG_ROUTE); + + return (reg & REG_ROUTE_LOCATION__MASK) >> __ffs(REG_ROUTE_LOCATION__MASK); +} + +static void efm32_spi_probe_dt(struct platform_device *pdev, + struct spi_master *master, struct efm32_spi_ddata *ddata) +{ + struct device_node *np = pdev->dev.of_node; + u32 location; + int ret; + + ret = of_property_read_u32(np, "energymicro,location", &location); + + if (ret) + /* fall back to wrongly namespaced property */ + ret = of_property_read_u32(np, "efm32,location", &location); + + if (ret) + /* fall back to old and (wrongly) generic property "location" */ + ret = of_property_read_u32(np, "location", &location); + + if (!ret) { + dev_dbg(&pdev->dev, "using location %u\n", location); + } else { + /* default to location configured in hardware */ + location = efm32_spi_get_configured_location(ddata); + + dev_info(&pdev->dev, "fall back to location %u\n", location); + } + + ddata->pdata.location = location; +} + +static int efm32_spi_probe(struct platform_device *pdev) +{ + struct efm32_spi_ddata *ddata; + struct resource *res; + int ret; + struct spi_master *master; + struct device_node *np = pdev->dev.of_node; + int num_cs, i; + + if (!np) + return -EINVAL; + + num_cs = of_gpio_named_count(np, "cs-gpios"); + if (num_cs < 0) + return num_cs; + + master = spi_alloc_master(&pdev->dev, + sizeof(*ddata) + num_cs * sizeof(unsigned)); + if (!master) { + dev_dbg(&pdev->dev, + "failed to allocate spi master controller\n"); + return -ENOMEM; + } + platform_set_drvdata(pdev, master); + + master->dev.of_node = pdev->dev.of_node; + + master->num_chipselect = num_cs; + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH; + master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 16); + + ddata = spi_master_get_devdata(master); + + ddata->bitbang.master = master; + ddata->bitbang.chipselect = efm32_spi_chipselect; + ddata->bitbang.setup_transfer = efm32_spi_setup_transfer; + ddata->bitbang.txrx_bufs = efm32_spi_txrx_bufs; + + spin_lock_init(&ddata->lock); + init_completion(&ddata->done); + + ddata->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(ddata->clk)) { + ret = PTR_ERR(ddata->clk); + dev_err(&pdev->dev, "failed to get clock: %d\n", ret); + goto err; + } + + for (i = 0; i < num_cs; ++i) { + ret = of_get_named_gpio(np, "cs-gpios", i); + if (ret < 0) { + dev_err(&pdev->dev, "failed to get csgpio#%u (%d)\n", + i, ret); + goto err; + } + ddata->csgpio[i] = ret; + dev_dbg(&pdev->dev, "csgpio#%u = %u\n", i, ddata->csgpio[i]); + ret = devm_gpio_request_one(&pdev->dev, ddata->csgpio[i], + GPIOF_OUT_INIT_LOW, DRIVER_NAME); + if (ret < 0) { + dev_err(&pdev->dev, + "failed to configure csgpio#%u (%d)\n", + i, ret); + goto err; + } + } + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) { + ret = -ENODEV; + dev_err(&pdev->dev, "failed to determine base address\n"); + goto err; + } + + if (resource_size(res) < 0x60) { + ret = -EINVAL; + dev_err(&pdev->dev, "memory resource too small\n"); + goto err; + } + + ddata->base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(ddata->base)) { + ret = PTR_ERR(ddata->base); + goto err; + } + + ret = platform_get_irq(pdev, 0); + if (ret <= 0) { + dev_err(&pdev->dev, "failed to get rx irq (%d)\n", ret); + goto err; + } + + ddata->rxirq = ret; + + ret = platform_get_irq(pdev, 1); + if (ret <= 0) + ret = ddata->rxirq + 1; + + ddata->txirq = ret; + + ret = clk_prepare_enable(ddata->clk); + if (ret < 0) { + dev_err(&pdev->dev, "failed to enable clock (%d)\n", ret); + goto err; + } + + efm32_spi_probe_dt(pdev, master, ddata); + + efm32_spi_write32(ddata, 0, REG_IEN); + efm32_spi_write32(ddata, REG_ROUTE_TXPEN | REG_ROUTE_RXPEN | + REG_ROUTE_CLKPEN | + REG_ROUTE_LOCATION(ddata->pdata.location), REG_ROUTE); + + ret = request_irq(ddata->rxirq, efm32_spi_rxirq, + 0, DRIVER_NAME " rx", ddata); + if (ret) { + dev_err(&pdev->dev, "failed to register rxirq (%d)\n", ret); + goto err_disable_clk; + } + + ret = request_irq(ddata->txirq, efm32_spi_txirq, + 0, DRIVER_NAME " tx", ddata); + if (ret) { + dev_err(&pdev->dev, "failed to register txirq (%d)\n", ret); + goto err_free_rx_irq; + } + + ret = spi_bitbang_start(&ddata->bitbang); + if (ret) { + dev_err(&pdev->dev, "spi_bitbang_start failed (%d)\n", ret); + + free_irq(ddata->txirq, ddata); +err_free_rx_irq: + free_irq(ddata->rxirq, ddata); +err_disable_clk: + clk_disable_unprepare(ddata->clk); +err: + spi_master_put(master); + } + + return ret; +} + +static int efm32_spi_remove(struct platform_device *pdev) +{ + struct spi_master *master = platform_get_drvdata(pdev); + struct efm32_spi_ddata *ddata = spi_master_get_devdata(master); + + spi_bitbang_stop(&ddata->bitbang); + + efm32_spi_write32(ddata, 0, REG_IEN); + + free_irq(ddata->txirq, ddata); + free_irq(ddata->rxirq, ddata); + clk_disable_unprepare(ddata->clk); + spi_master_put(master); + + return 0; +} + +static const struct of_device_id efm32_spi_dt_ids[] = { + { + .compatible = "energymicro,efm32-spi", + }, { + /* doesn't follow the "vendor,device" scheme, don't use */ + .compatible = "efm32,spi", + }, { + /* sentinel */ + } +}; +MODULE_DEVICE_TABLE(of, efm32_spi_dt_ids); + +static struct platform_driver efm32_spi_driver = { + .probe = efm32_spi_probe, + .remove = efm32_spi_remove, + + .driver = { + .name = DRIVER_NAME, + .of_match_table = efm32_spi_dt_ids, + }, +}; +module_platform_driver(efm32_spi_driver); + +MODULE_AUTHOR("Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de>"); +MODULE_DESCRIPTION("EFM32 SPI driver"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:" DRIVER_NAME); diff --git a/drivers/spi/spi-ep93xx.c b/drivers/spi/spi-ep93xx.c new file mode 100644 index 000000000..bb00be8d1 --- /dev/null +++ b/drivers/spi/spi-ep93xx.c @@ -0,0 +1,976 @@ +/* + * Driver for Cirrus Logic EP93xx SPI controller. + * + * Copyright (C) 2010-2011 Mika Westerberg + * + * Explicit FIFO handling code was inspired by amba-pl022 driver. + * + * Chip select support using other than built-in GPIOs by H. Hartley Sweeten. + * + * For more information about the SPI controller see documentation on Cirrus + * Logic web site: + * http://www.cirrus.com/en/pubs/manual/EP93xx_Users_Guide_UM1.pdf + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/io.h> +#include <linux/clk.h> +#include <linux/err.h> +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/dmaengine.h> +#include <linux/bitops.h> +#include <linux/interrupt.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/sched.h> +#include <linux/scatterlist.h> +#include <linux/spi/spi.h> + +#include <linux/platform_data/dma-ep93xx.h> +#include <linux/platform_data/spi-ep93xx.h> + +#define SSPCR0 0x0000 +#define SSPCR0_MODE_SHIFT 6 +#define SSPCR0_SCR_SHIFT 8 + +#define SSPCR1 0x0004 +#define SSPCR1_RIE BIT(0) +#define SSPCR1_TIE BIT(1) +#define SSPCR1_RORIE BIT(2) +#define SSPCR1_LBM BIT(3) +#define SSPCR1_SSE BIT(4) +#define SSPCR1_MS BIT(5) +#define SSPCR1_SOD BIT(6) + +#define SSPDR 0x0008 + +#define SSPSR 0x000c +#define SSPSR_TFE BIT(0) +#define SSPSR_TNF BIT(1) +#define SSPSR_RNE BIT(2) +#define SSPSR_RFF BIT(3) +#define SSPSR_BSY BIT(4) +#define SSPCPSR 0x0010 + +#define SSPIIR 0x0014 +#define SSPIIR_RIS BIT(0) +#define SSPIIR_TIS BIT(1) +#define SSPIIR_RORIS BIT(2) +#define SSPICR SSPIIR + +/* timeout in milliseconds */ +#define SPI_TIMEOUT 5 +/* maximum depth of RX/TX FIFO */ +#define SPI_FIFO_SIZE 8 + +/** + * struct ep93xx_spi - EP93xx SPI controller structure + * @pdev: pointer to platform device + * @clk: clock for the controller + * @regs_base: pointer to ioremap()'d registers + * @sspdr_phys: physical address of the SSPDR register + * @wait: wait here until given transfer is completed + * @current_msg: message that is currently processed (or %NULL if none) + * @tx: current byte in transfer to transmit + * @rx: current byte in transfer to receive + * @fifo_level: how full is FIFO (%0..%SPI_FIFO_SIZE - %1). Receiving one + * frame decreases this level and sending one frame increases it. + * @dma_rx: RX DMA channel + * @dma_tx: TX DMA channel + * @dma_rx_data: RX parameters passed to the DMA engine + * @dma_tx_data: TX parameters passed to the DMA engine + * @rx_sgt: sg table for RX transfers + * @tx_sgt: sg table for TX transfers + * @zeropage: dummy page used as RX buffer when only TX buffer is passed in by + * the client + */ +struct ep93xx_spi { + const struct platform_device *pdev; + struct clk *clk; + void __iomem *regs_base; + unsigned long sspdr_phys; + struct completion wait; + struct spi_message *current_msg; + size_t tx; + size_t rx; + size_t fifo_level; + struct dma_chan *dma_rx; + struct dma_chan *dma_tx; + struct ep93xx_dma_data dma_rx_data; + struct ep93xx_dma_data dma_tx_data; + struct sg_table rx_sgt; + struct sg_table tx_sgt; + void *zeropage; +}; + +/** + * struct ep93xx_spi_chip - SPI device hardware settings + * @spi: back pointer to the SPI device + * @ops: private chip operations + */ +struct ep93xx_spi_chip { + const struct spi_device *spi; + struct ep93xx_spi_chip_ops *ops; +}; + +/* converts bits per word to CR0.DSS value */ +#define bits_per_word_to_dss(bpw) ((bpw) - 1) + +static void ep93xx_spi_write_u8(const struct ep93xx_spi *espi, + u16 reg, u8 value) +{ + writeb(value, espi->regs_base + reg); +} + +static u8 ep93xx_spi_read_u8(const struct ep93xx_spi *spi, u16 reg) +{ + return readb(spi->regs_base + reg); +} + +static void ep93xx_spi_write_u16(const struct ep93xx_spi *espi, + u16 reg, u16 value) +{ + writew(value, espi->regs_base + reg); +} + +static u16 ep93xx_spi_read_u16(const struct ep93xx_spi *spi, u16 reg) +{ + return readw(spi->regs_base + reg); +} + +static int ep93xx_spi_enable(const struct ep93xx_spi *espi) +{ + u8 regval; + int err; + + err = clk_enable(espi->clk); + if (err) + return err; + + regval = ep93xx_spi_read_u8(espi, SSPCR1); + regval |= SSPCR1_SSE; + ep93xx_spi_write_u8(espi, SSPCR1, regval); + + return 0; +} + +static void ep93xx_spi_disable(const struct ep93xx_spi *espi) +{ + u8 regval; + + regval = ep93xx_spi_read_u8(espi, SSPCR1); + regval &= ~SSPCR1_SSE; + ep93xx_spi_write_u8(espi, SSPCR1, regval); + + clk_disable(espi->clk); +} + +static void ep93xx_spi_enable_interrupts(const struct ep93xx_spi *espi) +{ + u8 regval; + + regval = ep93xx_spi_read_u8(espi, SSPCR1); + regval |= (SSPCR1_RORIE | SSPCR1_TIE | SSPCR1_RIE); + ep93xx_spi_write_u8(espi, SSPCR1, regval); +} + +static void ep93xx_spi_disable_interrupts(const struct ep93xx_spi *espi) +{ + u8 regval; + + regval = ep93xx_spi_read_u8(espi, SSPCR1); + regval &= ~(SSPCR1_RORIE | SSPCR1_TIE | SSPCR1_RIE); + ep93xx_spi_write_u8(espi, SSPCR1, regval); +} + +/** + * ep93xx_spi_calc_divisors() - calculates SPI clock divisors + * @espi: ep93xx SPI controller struct + * @rate: desired SPI output clock rate + * @div_cpsr: pointer to return the cpsr (pre-scaler) divider + * @div_scr: pointer to return the scr divider + */ +static int ep93xx_spi_calc_divisors(const struct ep93xx_spi *espi, + u32 rate, u8 *div_cpsr, u8 *div_scr) +{ + struct spi_master *master = platform_get_drvdata(espi->pdev); + unsigned long spi_clk_rate = clk_get_rate(espi->clk); + int cpsr, scr; + + /* + * Make sure that max value is between values supported by the + * controller. Note that minimum value is already checked in + * ep93xx_spi_transfer_one_message(). + */ + rate = clamp(rate, master->min_speed_hz, master->max_speed_hz); + + /* + * Calculate divisors so that we can get speed according the + * following formula: + * rate = spi_clock_rate / (cpsr * (1 + scr)) + * + * cpsr must be even number and starts from 2, scr can be any number + * between 0 and 255. + */ + for (cpsr = 2; cpsr <= 254; cpsr += 2) { + for (scr = 0; scr <= 255; scr++) { + if ((spi_clk_rate / (cpsr * (scr + 1))) <= rate) { + *div_scr = (u8)scr; + *div_cpsr = (u8)cpsr; + return 0; + } + } + } + + return -EINVAL; +} + +static void ep93xx_spi_cs_control(struct spi_device *spi, bool control) +{ + struct ep93xx_spi_chip *chip = spi_get_ctldata(spi); + int value = (spi->mode & SPI_CS_HIGH) ? control : !control; + + if (chip->ops && chip->ops->cs_control) + chip->ops->cs_control(spi, value); +} + +/** + * ep93xx_spi_setup() - setup an SPI device + * @spi: SPI device to setup + * + * This function sets up SPI device mode, speed etc. Can be called multiple + * times for a single device. Returns %0 in case of success, negative error in + * case of failure. When this function returns success, the device is + * deselected. + */ +static int ep93xx_spi_setup(struct spi_device *spi) +{ + struct ep93xx_spi *espi = spi_master_get_devdata(spi->master); + struct ep93xx_spi_chip *chip; + + chip = spi_get_ctldata(spi); + if (!chip) { + dev_dbg(&espi->pdev->dev, "initial setup for %s\n", + spi->modalias); + + chip = kzalloc(sizeof(*chip), GFP_KERNEL); + if (!chip) + return -ENOMEM; + + chip->spi = spi; + chip->ops = spi->controller_data; + + if (chip->ops && chip->ops->setup) { + int ret = chip->ops->setup(spi); + + if (ret) { + kfree(chip); + return ret; + } + } + + spi_set_ctldata(spi, chip); + } + + ep93xx_spi_cs_control(spi, false); + return 0; +} + +/** + * ep93xx_spi_cleanup() - cleans up master controller specific state + * @spi: SPI device to cleanup + * + * This function releases master controller specific state for given @spi + * device. + */ +static void ep93xx_spi_cleanup(struct spi_device *spi) +{ + struct ep93xx_spi_chip *chip; + + chip = spi_get_ctldata(spi); + if (chip) { + if (chip->ops && chip->ops->cleanup) + chip->ops->cleanup(spi); + spi_set_ctldata(spi, NULL); + kfree(chip); + } +} + +/** + * ep93xx_spi_chip_setup() - configures hardware according to given @chip + * @espi: ep93xx SPI controller struct + * @chip: chip specific settings + * @speed_hz: transfer speed + * @bits_per_word: transfer bits_per_word + */ +static int ep93xx_spi_chip_setup(const struct ep93xx_spi *espi, + const struct ep93xx_spi_chip *chip, + u32 speed_hz, u8 bits_per_word) +{ + u8 dss = bits_per_word_to_dss(bits_per_word); + u8 div_cpsr = 0; + u8 div_scr = 0; + u16 cr0; + int err; + + err = ep93xx_spi_calc_divisors(espi, speed_hz, &div_cpsr, &div_scr); + if (err) + return err; + + cr0 = div_scr << SSPCR0_SCR_SHIFT; + cr0 |= (chip->spi->mode & (SPI_CPHA|SPI_CPOL)) << SSPCR0_MODE_SHIFT; + cr0 |= dss; + + dev_dbg(&espi->pdev->dev, "setup: mode %d, cpsr %d, scr %d, dss %d\n", + chip->spi->mode, div_cpsr, div_scr, dss); + dev_dbg(&espi->pdev->dev, "setup: cr0 %#x\n", cr0); + + ep93xx_spi_write_u8(espi, SSPCPSR, div_cpsr); + ep93xx_spi_write_u16(espi, SSPCR0, cr0); + + return 0; +} + +static void ep93xx_do_write(struct ep93xx_spi *espi, struct spi_transfer *t) +{ + if (t->bits_per_word > 8) { + u16 tx_val = 0; + + if (t->tx_buf) + tx_val = ((u16 *)t->tx_buf)[espi->tx]; + ep93xx_spi_write_u16(espi, SSPDR, tx_val); + espi->tx += sizeof(tx_val); + } else { + u8 tx_val = 0; + + if (t->tx_buf) + tx_val = ((u8 *)t->tx_buf)[espi->tx]; + ep93xx_spi_write_u8(espi, SSPDR, tx_val); + espi->tx += sizeof(tx_val); + } +} + +static void ep93xx_do_read(struct ep93xx_spi *espi, struct spi_transfer *t) +{ + if (t->bits_per_word > 8) { + u16 rx_val; + + rx_val = ep93xx_spi_read_u16(espi, SSPDR); + if (t->rx_buf) + ((u16 *)t->rx_buf)[espi->rx] = rx_val; + espi->rx += sizeof(rx_val); + } else { + u8 rx_val; + + rx_val = ep93xx_spi_read_u8(espi, SSPDR); + if (t->rx_buf) + ((u8 *)t->rx_buf)[espi->rx] = rx_val; + espi->rx += sizeof(rx_val); + } +} + +/** + * ep93xx_spi_read_write() - perform next RX/TX transfer + * @espi: ep93xx SPI controller struct + * + * This function transfers next bytes (or half-words) to/from RX/TX FIFOs. If + * called several times, the whole transfer will be completed. Returns + * %-EINPROGRESS when current transfer was not yet completed otherwise %0. + * + * When this function is finished, RX FIFO should be empty and TX FIFO should be + * full. + */ +static int ep93xx_spi_read_write(struct ep93xx_spi *espi) +{ + struct spi_message *msg = espi->current_msg; + struct spi_transfer *t = msg->state; + + /* read as long as RX FIFO has frames in it */ + while ((ep93xx_spi_read_u8(espi, SSPSR) & SSPSR_RNE)) { + ep93xx_do_read(espi, t); + espi->fifo_level--; + } + + /* write as long as TX FIFO has room */ + while (espi->fifo_level < SPI_FIFO_SIZE && espi->tx < t->len) { + ep93xx_do_write(espi, t); + espi->fifo_level++; + } + + if (espi->rx == t->len) + return 0; + + return -EINPROGRESS; +} + +static void ep93xx_spi_pio_transfer(struct ep93xx_spi *espi) +{ + /* + * Now everything is set up for the current transfer. We prime the TX + * FIFO, enable interrupts, and wait for the transfer to complete. + */ + if (ep93xx_spi_read_write(espi)) { + ep93xx_spi_enable_interrupts(espi); + wait_for_completion(&espi->wait); + } +} + +/** + * ep93xx_spi_dma_prepare() - prepares a DMA transfer + * @espi: ep93xx SPI controller struct + * @dir: DMA transfer direction + * + * Function configures the DMA, maps the buffer and prepares the DMA + * descriptor. Returns a valid DMA descriptor in case of success and ERR_PTR + * in case of failure. + */ +static struct dma_async_tx_descriptor * +ep93xx_spi_dma_prepare(struct ep93xx_spi *espi, enum dma_transfer_direction dir) +{ + struct spi_transfer *t = espi->current_msg->state; + struct dma_async_tx_descriptor *txd; + enum dma_slave_buswidth buswidth; + struct dma_slave_config conf; + struct scatterlist *sg; + struct sg_table *sgt; + struct dma_chan *chan; + const void *buf, *pbuf; + size_t len = t->len; + int i, ret, nents; + + if (t->bits_per_word > 8) + buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES; + else + buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE; + + memset(&conf, 0, sizeof(conf)); + conf.direction = dir; + + if (dir == DMA_DEV_TO_MEM) { + chan = espi->dma_rx; + buf = t->rx_buf; + sgt = &espi->rx_sgt; + + conf.src_addr = espi->sspdr_phys; + conf.src_addr_width = buswidth; + } else { + chan = espi->dma_tx; + buf = t->tx_buf; + sgt = &espi->tx_sgt; + + conf.dst_addr = espi->sspdr_phys; + conf.dst_addr_width = buswidth; + } + + ret = dmaengine_slave_config(chan, &conf); + if (ret) + return ERR_PTR(ret); + + /* + * We need to split the transfer into PAGE_SIZE'd chunks. This is + * because we are using @espi->zeropage to provide a zero RX buffer + * for the TX transfers and we have only allocated one page for that. + * + * For performance reasons we allocate a new sg_table only when + * needed. Otherwise we will re-use the current one. Eventually the + * last sg_table is released in ep93xx_spi_release_dma(). + */ + + nents = DIV_ROUND_UP(len, PAGE_SIZE); + if (nents != sgt->nents) { + sg_free_table(sgt); + + ret = sg_alloc_table(sgt, nents, GFP_KERNEL); + if (ret) + return ERR_PTR(ret); + } + + pbuf = buf; + for_each_sg(sgt->sgl, sg, sgt->nents, i) { + size_t bytes = min_t(size_t, len, PAGE_SIZE); + + if (buf) { + sg_set_page(sg, virt_to_page(pbuf), bytes, + offset_in_page(pbuf)); + } else { + sg_set_page(sg, virt_to_page(espi->zeropage), + bytes, 0); + } + + pbuf += bytes; + len -= bytes; + } + + if (WARN_ON(len)) { + dev_warn(&espi->pdev->dev, "len = %zu expected 0!\n", len); + return ERR_PTR(-EINVAL); + } + + nents = dma_map_sg(chan->device->dev, sgt->sgl, sgt->nents, dir); + if (!nents) + return ERR_PTR(-ENOMEM); + + txd = dmaengine_prep_slave_sg(chan, sgt->sgl, nents, dir, DMA_CTRL_ACK); + if (!txd) { + dma_unmap_sg(chan->device->dev, sgt->sgl, sgt->nents, dir); + return ERR_PTR(-ENOMEM); + } + return txd; +} + +/** + * ep93xx_spi_dma_finish() - finishes with a DMA transfer + * @espi: ep93xx SPI controller struct + * @dir: DMA transfer direction + * + * Function finishes with the DMA transfer. After this, the DMA buffer is + * unmapped. + */ +static void ep93xx_spi_dma_finish(struct ep93xx_spi *espi, + enum dma_transfer_direction dir) +{ + struct dma_chan *chan; + struct sg_table *sgt; + + if (dir == DMA_DEV_TO_MEM) { + chan = espi->dma_rx; + sgt = &espi->rx_sgt; + } else { + chan = espi->dma_tx; + sgt = &espi->tx_sgt; + } + + dma_unmap_sg(chan->device->dev, sgt->sgl, sgt->nents, dir); +} + +static void ep93xx_spi_dma_callback(void *callback_param) +{ + complete(callback_param); +} + +static void ep93xx_spi_dma_transfer(struct ep93xx_spi *espi) +{ + struct spi_message *msg = espi->current_msg; + struct dma_async_tx_descriptor *rxd, *txd; + + rxd = ep93xx_spi_dma_prepare(espi, DMA_DEV_TO_MEM); + if (IS_ERR(rxd)) { + dev_err(&espi->pdev->dev, "DMA RX failed: %ld\n", PTR_ERR(rxd)); + msg->status = PTR_ERR(rxd); + return; + } + + txd = ep93xx_spi_dma_prepare(espi, DMA_MEM_TO_DEV); + if (IS_ERR(txd)) { + ep93xx_spi_dma_finish(espi, DMA_DEV_TO_MEM); + dev_err(&espi->pdev->dev, "DMA TX failed: %ld\n", PTR_ERR(rxd)); + msg->status = PTR_ERR(txd); + return; + } + + /* We are ready when RX is done */ + rxd->callback = ep93xx_spi_dma_callback; + rxd->callback_param = &espi->wait; + + /* Now submit both descriptors and wait while they finish */ + dmaengine_submit(rxd); + dmaengine_submit(txd); + + dma_async_issue_pending(espi->dma_rx); + dma_async_issue_pending(espi->dma_tx); + + wait_for_completion(&espi->wait); + + ep93xx_spi_dma_finish(espi, DMA_MEM_TO_DEV); + ep93xx_spi_dma_finish(espi, DMA_DEV_TO_MEM); +} + +/** + * ep93xx_spi_process_transfer() - processes one SPI transfer + * @espi: ep93xx SPI controller struct + * @msg: current message + * @t: transfer to process + * + * This function processes one SPI transfer given in @t. Function waits until + * transfer is complete (may sleep) and updates @msg->status based on whether + * transfer was successfully processed or not. + */ +static void ep93xx_spi_process_transfer(struct ep93xx_spi *espi, + struct spi_message *msg, + struct spi_transfer *t) +{ + struct ep93xx_spi_chip *chip = spi_get_ctldata(msg->spi); + int err; + + msg->state = t; + + err = ep93xx_spi_chip_setup(espi, chip, t->speed_hz, t->bits_per_word); + if (err) { + dev_err(&espi->pdev->dev, + "failed to setup chip for transfer\n"); + msg->status = err; + return; + } + + espi->rx = 0; + espi->tx = 0; + + /* + * There is no point of setting up DMA for the transfers which will + * fit into the FIFO and can be transferred with a single interrupt. + * So in these cases we will be using PIO and don't bother for DMA. + */ + if (espi->dma_rx && t->len > SPI_FIFO_SIZE) + ep93xx_spi_dma_transfer(espi); + else + ep93xx_spi_pio_transfer(espi); + + /* + * In case of error during transmit, we bail out from processing + * the message. + */ + if (msg->status) + return; + + msg->actual_length += t->len; + + /* + * After this transfer is finished, perform any possible + * post-transfer actions requested by the protocol driver. + */ + if (t->delay_usecs) { + set_current_state(TASK_UNINTERRUPTIBLE); + schedule_timeout(usecs_to_jiffies(t->delay_usecs)); + } + if (t->cs_change) { + if (!list_is_last(&t->transfer_list, &msg->transfers)) { + /* + * In case protocol driver is asking us to drop the + * chipselect briefly, we let the scheduler to handle + * any "delay" here. + */ + ep93xx_spi_cs_control(msg->spi, false); + cond_resched(); + ep93xx_spi_cs_control(msg->spi, true); + } + } +} + +/* + * ep93xx_spi_process_message() - process one SPI message + * @espi: ep93xx SPI controller struct + * @msg: message to process + * + * This function processes a single SPI message. We go through all transfers in + * the message and pass them to ep93xx_spi_process_transfer(). Chipselect is + * asserted during the whole message (unless per transfer cs_change is set). + * + * @msg->status contains %0 in case of success or negative error code in case of + * failure. + */ +static void ep93xx_spi_process_message(struct ep93xx_spi *espi, + struct spi_message *msg) +{ + unsigned long timeout; + struct spi_transfer *t; + int err; + + /* + * Enable the SPI controller and its clock. + */ + err = ep93xx_spi_enable(espi); + if (err) { + dev_err(&espi->pdev->dev, "failed to enable SPI controller\n"); + msg->status = err; + return; + } + + /* + * Just to be sure: flush any data from RX FIFO. + */ + timeout = jiffies + msecs_to_jiffies(SPI_TIMEOUT); + while (ep93xx_spi_read_u16(espi, SSPSR) & SSPSR_RNE) { + if (time_after(jiffies, timeout)) { + dev_warn(&espi->pdev->dev, + "timeout while flushing RX FIFO\n"); + msg->status = -ETIMEDOUT; + return; + } + ep93xx_spi_read_u16(espi, SSPDR); + } + + /* + * We explicitly handle FIFO level. This way we don't have to check TX + * FIFO status using %SSPSR_TNF bit which may cause RX FIFO overruns. + */ + espi->fifo_level = 0; + + /* + * Assert the chipselect. + */ + ep93xx_spi_cs_control(msg->spi, true); + + list_for_each_entry(t, &msg->transfers, transfer_list) { + ep93xx_spi_process_transfer(espi, msg, t); + if (msg->status) + break; + } + + /* + * Now the whole message is transferred (or failed for some reason). We + * deselect the device and disable the SPI controller. + */ + ep93xx_spi_cs_control(msg->spi, false); + ep93xx_spi_disable(espi); +} + +static int ep93xx_spi_transfer_one_message(struct spi_master *master, + struct spi_message *msg) +{ + struct ep93xx_spi *espi = spi_master_get_devdata(master); + + msg->state = NULL; + msg->status = 0; + msg->actual_length = 0; + + espi->current_msg = msg; + ep93xx_spi_process_message(espi, msg); + espi->current_msg = NULL; + + spi_finalize_current_message(master); + + return 0; +} + +static irqreturn_t ep93xx_spi_interrupt(int irq, void *dev_id) +{ + struct ep93xx_spi *espi = dev_id; + u8 irq_status = ep93xx_spi_read_u8(espi, SSPIIR); + + /* + * If we got ROR (receive overrun) interrupt we know that something is + * wrong. Just abort the message. + */ + if (unlikely(irq_status & SSPIIR_RORIS)) { + /* clear the overrun interrupt */ + ep93xx_spi_write_u8(espi, SSPICR, 0); + dev_warn(&espi->pdev->dev, + "receive overrun, aborting the message\n"); + espi->current_msg->status = -EIO; + } else { + /* + * Interrupt is either RX (RIS) or TX (TIS). For both cases we + * simply execute next data transfer. + */ + if (ep93xx_spi_read_write(espi)) { + /* + * In normal case, there still is some processing left + * for current transfer. Let's wait for the next + * interrupt then. + */ + return IRQ_HANDLED; + } + } + + /* + * Current transfer is finished, either with error or with success. In + * any case we disable interrupts and notify the worker to handle + * any post-processing of the message. + */ + ep93xx_spi_disable_interrupts(espi); + complete(&espi->wait); + return IRQ_HANDLED; +} + +static bool ep93xx_spi_dma_filter(struct dma_chan *chan, void *filter_param) +{ + if (ep93xx_dma_chan_is_m2p(chan)) + return false; + + chan->private = filter_param; + return true; +} + +static int ep93xx_spi_setup_dma(struct ep93xx_spi *espi) +{ + dma_cap_mask_t mask; + int ret; + + espi->zeropage = (void *)get_zeroed_page(GFP_KERNEL); + if (!espi->zeropage) + return -ENOMEM; + + dma_cap_zero(mask); + dma_cap_set(DMA_SLAVE, mask); + + espi->dma_rx_data.port = EP93XX_DMA_SSP; + espi->dma_rx_data.direction = DMA_DEV_TO_MEM; + espi->dma_rx_data.name = "ep93xx-spi-rx"; + + espi->dma_rx = dma_request_channel(mask, ep93xx_spi_dma_filter, + &espi->dma_rx_data); + if (!espi->dma_rx) { + ret = -ENODEV; + goto fail_free_page; + } + + espi->dma_tx_data.port = EP93XX_DMA_SSP; + espi->dma_tx_data.direction = DMA_MEM_TO_DEV; + espi->dma_tx_data.name = "ep93xx-spi-tx"; + + espi->dma_tx = dma_request_channel(mask, ep93xx_spi_dma_filter, + &espi->dma_tx_data); + if (!espi->dma_tx) { + ret = -ENODEV; + goto fail_release_rx; + } + + return 0; + +fail_release_rx: + dma_release_channel(espi->dma_rx); + espi->dma_rx = NULL; +fail_free_page: + free_page((unsigned long)espi->zeropage); + + return ret; +} + +static void ep93xx_spi_release_dma(struct ep93xx_spi *espi) +{ + if (espi->dma_rx) { + dma_release_channel(espi->dma_rx); + sg_free_table(&espi->rx_sgt); + } + if (espi->dma_tx) { + dma_release_channel(espi->dma_tx); + sg_free_table(&espi->tx_sgt); + } + + if (espi->zeropage) + free_page((unsigned long)espi->zeropage); +} + +static int ep93xx_spi_probe(struct platform_device *pdev) +{ + struct spi_master *master; + struct ep93xx_spi_info *info; + struct ep93xx_spi *espi; + struct resource *res; + int irq; + int error; + + info = dev_get_platdata(&pdev->dev); + + irq = platform_get_irq(pdev, 0); + if (irq < 0) { + dev_err(&pdev->dev, "failed to get irq resources\n"); + return -EBUSY; + } + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) { + dev_err(&pdev->dev, "unable to get iomem resource\n"); + return -ENODEV; + } + + master = spi_alloc_master(&pdev->dev, sizeof(*espi)); + if (!master) + return -ENOMEM; + + master->setup = ep93xx_spi_setup; + master->transfer_one_message = ep93xx_spi_transfer_one_message; + master->cleanup = ep93xx_spi_cleanup; + master->bus_num = pdev->id; + master->num_chipselect = info->num_chipselect; + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH; + master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 16); + + platform_set_drvdata(pdev, master); + + espi = spi_master_get_devdata(master); + + espi->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(espi->clk)) { + dev_err(&pdev->dev, "unable to get spi clock\n"); + error = PTR_ERR(espi->clk); + goto fail_release_master; + } + + init_completion(&espi->wait); + + /* + * Calculate maximum and minimum supported clock rates + * for the controller. + */ + master->max_speed_hz = clk_get_rate(espi->clk) / 2; + master->min_speed_hz = clk_get_rate(espi->clk) / (254 * 256); + espi->pdev = pdev; + + espi->sspdr_phys = res->start + SSPDR; + + espi->regs_base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(espi->regs_base)) { + error = PTR_ERR(espi->regs_base); + goto fail_release_master; + } + + error = devm_request_irq(&pdev->dev, irq, ep93xx_spi_interrupt, + 0, "ep93xx-spi", espi); + if (error) { + dev_err(&pdev->dev, "failed to request irq\n"); + goto fail_release_master; + } + + if (info->use_dma && ep93xx_spi_setup_dma(espi)) + dev_warn(&pdev->dev, "DMA setup failed. Falling back to PIO\n"); + + /* make sure that the hardware is disabled */ + ep93xx_spi_write_u8(espi, SSPCR1, 0); + + error = devm_spi_register_master(&pdev->dev, master); + if (error) { + dev_err(&pdev->dev, "failed to register SPI master\n"); + goto fail_free_dma; + } + + dev_info(&pdev->dev, "EP93xx SPI Controller at 0x%08lx irq %d\n", + (unsigned long)res->start, irq); + + return 0; + +fail_free_dma: + ep93xx_spi_release_dma(espi); +fail_release_master: + spi_master_put(master); + + return error; +} + +static int ep93xx_spi_remove(struct platform_device *pdev) +{ + struct spi_master *master = platform_get_drvdata(pdev); + struct ep93xx_spi *espi = spi_master_get_devdata(master); + + ep93xx_spi_release_dma(espi); + + return 0; +} + +static struct platform_driver ep93xx_spi_driver = { + .driver = { + .name = "ep93xx-spi", + }, + .probe = ep93xx_spi_probe, + .remove = ep93xx_spi_remove, +}; +module_platform_driver(ep93xx_spi_driver); + +MODULE_DESCRIPTION("EP93xx SPI Controller driver"); +MODULE_AUTHOR("Mika Westerberg <mika.westerberg@iki.fi>"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:ep93xx-spi"); diff --git a/drivers/spi/spi-falcon.c b/drivers/spi/spi-falcon.c new file mode 100644 index 000000000..286b2c81f --- /dev/null +++ b/drivers/spi/spi-falcon.c @@ -0,0 +1,439 @@ +/* + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published + * by the Free Software Foundation. + * + * Copyright (C) 2012 Thomas Langer <thomas.langer@lantiq.com> + */ + +#include <linux/module.h> +#include <linux/device.h> +#include <linux/platform_device.h> +#include <linux/spi/spi.h> +#include <linux/delay.h> +#include <linux/of.h> +#include <linux/of_platform.h> + +#include <lantiq_soc.h> + +#define DRV_NAME "sflash-falcon" + +#define FALCON_SPI_XFER_BEGIN (1 << 0) +#define FALCON_SPI_XFER_END (1 << 1) + +/* Bus Read Configuration Register0 */ +#define BUSRCON0 0x00000010 +/* Bus Write Configuration Register0 */ +#define BUSWCON0 0x00000018 +/* Serial Flash Configuration Register */ +#define SFCON 0x00000080 +/* Serial Flash Time Register */ +#define SFTIME 0x00000084 +/* Serial Flash Status Register */ +#define SFSTAT 0x00000088 +/* Serial Flash Command Register */ +#define SFCMD 0x0000008C +/* Serial Flash Address Register */ +#define SFADDR 0x00000090 +/* Serial Flash Data Register */ +#define SFDATA 0x00000094 +/* Serial Flash I/O Control Register */ +#define SFIO 0x00000098 +/* EBU Clock Control Register */ +#define EBUCC 0x000000C4 + +/* Dummy Phase Length */ +#define SFCMD_DUMLEN_OFFSET 16 +#define SFCMD_DUMLEN_MASK 0x000F0000 +/* Chip Select */ +#define SFCMD_CS_OFFSET 24 +#define SFCMD_CS_MASK 0x07000000 +/* field offset */ +#define SFCMD_ALEN_OFFSET 20 +#define SFCMD_ALEN_MASK 0x00700000 +/* SCK Rise-edge Position */ +#define SFTIME_SCKR_POS_OFFSET 8 +#define SFTIME_SCKR_POS_MASK 0x00000F00 +/* SCK Period */ +#define SFTIME_SCK_PER_OFFSET 0 +#define SFTIME_SCK_PER_MASK 0x0000000F +/* SCK Fall-edge Position */ +#define SFTIME_SCKF_POS_OFFSET 12 +#define SFTIME_SCKF_POS_MASK 0x0000F000 +/* Device Size */ +#define SFCON_DEV_SIZE_A23_0 0x03000000 +#define SFCON_DEV_SIZE_MASK 0x0F000000 +/* Read Data Position */ +#define SFTIME_RD_POS_MASK 0x000F0000 +/* Data Output */ +#define SFIO_UNUSED_WD_MASK 0x0000000F +/* Command Opcode mask */ +#define SFCMD_OPC_MASK 0x000000FF +/* dlen bytes of data to write */ +#define SFCMD_DIR_WRITE 0x00000100 +/* Data Length offset */ +#define SFCMD_DLEN_OFFSET 9 +/* Command Error */ +#define SFSTAT_CMD_ERR 0x20000000 +/* Access Command Pending */ +#define SFSTAT_CMD_PEND 0x00400000 +/* Frequency set to 100MHz. */ +#define EBUCC_EBUDIV_SELF100 0x00000001 +/* Serial Flash */ +#define BUSRCON0_AGEN_SERIAL_FLASH 0xF0000000 +/* 8-bit multiplexed */ +#define BUSRCON0_PORTW_8_BIT_MUX 0x00000000 +/* Serial Flash */ +#define BUSWCON0_AGEN_SERIAL_FLASH 0xF0000000 +/* Chip Select after opcode */ +#define SFCMD_KEEP_CS_KEEP_SELECTED 0x00008000 + +#define CLOCK_100M 100000000 +#define CLOCK_50M 50000000 + +struct falcon_sflash { + u32 sfcmd; /* for caching of opcode, direction, ... */ + struct spi_master *master; +}; + +int falcon_sflash_xfer(struct spi_device *spi, struct spi_transfer *t, + unsigned long flags) +{ + struct device *dev = &spi->dev; + struct falcon_sflash *priv = spi_master_get_devdata(spi->master); + const u8 *txp = t->tx_buf; + u8 *rxp = t->rx_buf; + unsigned int bytelen = ((8 * t->len + 7) / 8); + unsigned int len, alen, dumlen; + u32 val; + enum { + state_init, + state_command_prepare, + state_write, + state_read, + state_disable_cs, + state_end + } state = state_init; + + do { + switch (state) { + case state_init: /* detect phase of upper layer sequence */ + { + /* initial write ? */ + if (flags & FALCON_SPI_XFER_BEGIN) { + if (!txp) { + dev_err(dev, + "BEGIN without tx data!\n"); + return -ENODATA; + } + /* + * Prepare the parts of the sfcmd register, + * which should not change during a sequence! + * Only exception are the length fields, + * especially alen and dumlen. + */ + + priv->sfcmd = ((spi->chip_select + << SFCMD_CS_OFFSET) + & SFCMD_CS_MASK); + priv->sfcmd |= SFCMD_KEEP_CS_KEEP_SELECTED; + priv->sfcmd |= *txp; + txp++; + bytelen--; + if (bytelen) { + /* + * more data: + * maybe address and/or dummy + */ + state = state_command_prepare; + break; + } else { + dev_dbg(dev, "write cmd %02X\n", + priv->sfcmd & SFCMD_OPC_MASK); + } + } + /* continued write ? */ + if (txp && bytelen) { + state = state_write; + break; + } + /* read data? */ + if (rxp && bytelen) { + state = state_read; + break; + } + /* end of sequence? */ + if (flags & FALCON_SPI_XFER_END) + state = state_disable_cs; + else + state = state_end; + break; + } + /* collect tx data for address and dummy phase */ + case state_command_prepare: + { + /* txp is valid, already checked */ + val = 0; + alen = 0; + dumlen = 0; + while (bytelen > 0) { + if (alen < 3) { + val = (val << 8) | (*txp++); + alen++; + } else if ((dumlen < 15) && (*txp == 0)) { + /* + * assume dummy bytes are set to 0 + * from upper layer + */ + dumlen++; + txp++; + } else { + break; + } + bytelen--; + } + priv->sfcmd &= ~(SFCMD_ALEN_MASK | SFCMD_DUMLEN_MASK); + priv->sfcmd |= (alen << SFCMD_ALEN_OFFSET) | + (dumlen << SFCMD_DUMLEN_OFFSET); + if (alen > 0) + ltq_ebu_w32(val, SFADDR); + + dev_dbg(dev, "wr %02X, alen=%d (addr=%06X) dlen=%d\n", + priv->sfcmd & SFCMD_OPC_MASK, + alen, val, dumlen); + + if (bytelen > 0) { + /* continue with write */ + state = state_write; + } else if (flags & FALCON_SPI_XFER_END) { + /* end of sequence? */ + state = state_disable_cs; + } else { + /* + * go to end and expect another + * call (read or write) + */ + state = state_end; + } + break; + } + case state_write: + { + /* txp still valid */ + priv->sfcmd |= SFCMD_DIR_WRITE; + len = 0; + val = 0; + do { + if (bytelen--) + val |= (*txp++) << (8 * len++); + if ((flags & FALCON_SPI_XFER_END) + && (bytelen == 0)) { + priv->sfcmd &= + ~SFCMD_KEEP_CS_KEEP_SELECTED; + } + if ((len == 4) || (bytelen == 0)) { + ltq_ebu_w32(val, SFDATA); + ltq_ebu_w32(priv->sfcmd + | (len<<SFCMD_DLEN_OFFSET), + SFCMD); + len = 0; + val = 0; + priv->sfcmd &= ~(SFCMD_ALEN_MASK + | SFCMD_DUMLEN_MASK); + } + } while (bytelen); + state = state_end; + break; + } + case state_read: + { + /* read data */ + priv->sfcmd &= ~SFCMD_DIR_WRITE; + do { + if ((flags & FALCON_SPI_XFER_END) + && (bytelen <= 4)) { + priv->sfcmd &= + ~SFCMD_KEEP_CS_KEEP_SELECTED; + } + len = (bytelen > 4) ? 4 : bytelen; + bytelen -= len; + ltq_ebu_w32(priv->sfcmd + | (len << SFCMD_DLEN_OFFSET), SFCMD); + priv->sfcmd &= ~(SFCMD_ALEN_MASK + | SFCMD_DUMLEN_MASK); + do { + val = ltq_ebu_r32(SFSTAT); + if (val & SFSTAT_CMD_ERR) { + /* reset error status */ + dev_err(dev, "SFSTAT: CMD_ERR"); + dev_err(dev, " (%x)\n", val); + ltq_ebu_w32(SFSTAT_CMD_ERR, + SFSTAT); + return -EBADE; + } + } while (val & SFSTAT_CMD_PEND); + val = ltq_ebu_r32(SFDATA); + do { + *rxp = (val & 0xFF); + rxp++; + val >>= 8; + len--; + } while (len); + } while (bytelen); + state = state_end; + break; + } + case state_disable_cs: + { + priv->sfcmd &= ~SFCMD_KEEP_CS_KEEP_SELECTED; + ltq_ebu_w32(priv->sfcmd | (0 << SFCMD_DLEN_OFFSET), + SFCMD); + val = ltq_ebu_r32(SFSTAT); + if (val & SFSTAT_CMD_ERR) { + /* reset error status */ + dev_err(dev, "SFSTAT: CMD_ERR (%x)\n", val); + ltq_ebu_w32(SFSTAT_CMD_ERR, SFSTAT); + return -EBADE; + } + state = state_end; + break; + } + case state_end: + break; + } + } while (state != state_end); + + return 0; +} + +static int falcon_sflash_setup(struct spi_device *spi) +{ + unsigned int i; + unsigned long flags; + + spin_lock_irqsave(&ebu_lock, flags); + + if (spi->max_speed_hz >= CLOCK_100M) { + /* set EBU clock to 100 MHz */ + ltq_sys1_w32_mask(0, EBUCC_EBUDIV_SELF100, EBUCC); + i = 1; /* divider */ + } else { + /* set EBU clock to 50 MHz */ + ltq_sys1_w32_mask(EBUCC_EBUDIV_SELF100, 0, EBUCC); + + /* search for suitable divider */ + for (i = 1; i < 7; i++) { + if (CLOCK_50M / i <= spi->max_speed_hz) + break; + } + } + + /* setup period of serial clock */ + ltq_ebu_w32_mask(SFTIME_SCKF_POS_MASK + | SFTIME_SCKR_POS_MASK + | SFTIME_SCK_PER_MASK, + (i << SFTIME_SCKR_POS_OFFSET) + | (i << (SFTIME_SCK_PER_OFFSET + 1)), + SFTIME); + + /* + * set some bits of unused_wd, to not trigger HOLD/WP + * signals on non QUAD flashes + */ + ltq_ebu_w32((SFIO_UNUSED_WD_MASK & (0x8 | 0x4)), SFIO); + + ltq_ebu_w32(BUSRCON0_AGEN_SERIAL_FLASH | BUSRCON0_PORTW_8_BIT_MUX, + BUSRCON0); + ltq_ebu_w32(BUSWCON0_AGEN_SERIAL_FLASH, BUSWCON0); + /* set address wrap around to maximum for 24-bit addresses */ + ltq_ebu_w32_mask(SFCON_DEV_SIZE_MASK, SFCON_DEV_SIZE_A23_0, SFCON); + + spin_unlock_irqrestore(&ebu_lock, flags); + + return 0; +} + +static int falcon_sflash_xfer_one(struct spi_master *master, + struct spi_message *m) +{ + struct falcon_sflash *priv = spi_master_get_devdata(master); + struct spi_transfer *t; + unsigned long spi_flags; + unsigned long flags; + int ret = 0; + + priv->sfcmd = 0; + m->actual_length = 0; + + spi_flags = FALCON_SPI_XFER_BEGIN; + list_for_each_entry(t, &m->transfers, transfer_list) { + if (list_is_last(&t->transfer_list, &m->transfers)) + spi_flags |= FALCON_SPI_XFER_END; + + spin_lock_irqsave(&ebu_lock, flags); + ret = falcon_sflash_xfer(m->spi, t, spi_flags); + spin_unlock_irqrestore(&ebu_lock, flags); + + if (ret) + break; + + m->actual_length += t->len; + + WARN_ON(t->delay_usecs || t->cs_change); + spi_flags = 0; + } + + m->status = ret; + spi_finalize_current_message(master); + + return 0; +} + +static int falcon_sflash_probe(struct platform_device *pdev) +{ + struct falcon_sflash *priv; + struct spi_master *master; + int ret; + + if (ltq_boot_select() != BS_SPI) { + dev_err(&pdev->dev, "invalid bootstrap options\n"); + return -ENODEV; + } + + master = spi_alloc_master(&pdev->dev, sizeof(*priv)); + if (!master) + return -ENOMEM; + + priv = spi_master_get_devdata(master); + priv->master = master; + + master->mode_bits = SPI_MODE_3; + master->flags = SPI_MASTER_HALF_DUPLEX; + master->setup = falcon_sflash_setup; + master->transfer_one_message = falcon_sflash_xfer_one; + master->dev.of_node = pdev->dev.of_node; + + ret = devm_spi_register_master(&pdev->dev, master); + if (ret) + spi_master_put(master); + return ret; +} + +static const struct of_device_id falcon_sflash_match[] = { + { .compatible = "lantiq,sflash-falcon" }, + {}, +}; +MODULE_DEVICE_TABLE(of, falcon_sflash_match); + +static struct platform_driver falcon_sflash_driver = { + .probe = falcon_sflash_probe, + .driver = { + .name = DRV_NAME, + .of_match_table = falcon_sflash_match, + } +}; + +module_platform_driver(falcon_sflash_driver); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("Lantiq Falcon SPI/SFLASH controller driver"); diff --git a/drivers/spi/spi-fsl-cpm.c b/drivers/spi/spi-fsl-cpm.c new file mode 100644 index 000000000..896add8cf --- /dev/null +++ b/drivers/spi/spi-fsl-cpm.c @@ -0,0 +1,406 @@ +/* + * Freescale SPI controller driver cpm functions. + * + * Maintainer: Kumar Gala + * + * Copyright (C) 2006 Polycom, Inc. + * Copyright 2010 Freescale Semiconductor, Inc. + * + * CPM SPI and QE buffer descriptors mode support: + * Copyright (c) 2009 MontaVista Software, Inc. + * Author: Anton Vorontsov <avorontsov@ru.mvista.com> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + */ +#include <asm/cpm.h> +#include <asm/qe.h> +#include <linux/dma-mapping.h> +#include <linux/fsl_devices.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of_address.h> +#include <linux/spi/spi.h> +#include <linux/types.h> +#include <linux/platform_device.h> + +#include "spi-fsl-cpm.h" +#include "spi-fsl-lib.h" +#include "spi-fsl-spi.h" + +/* CPM1 and CPM2 are mutually exclusive. */ +#ifdef CONFIG_CPM1 +#include <asm/cpm1.h> +#define CPM_SPI_CMD mk_cr_cmd(CPM_CR_CH_SPI, 0) +#else +#include <asm/cpm2.h> +#define CPM_SPI_CMD mk_cr_cmd(CPM_CR_SPI_PAGE, CPM_CR_SPI_SBLOCK, 0, 0) +#endif + +#define SPIE_TXB 0x00000200 /* Last char is written to tx fifo */ +#define SPIE_RXB 0x00000100 /* Last char is written to rx buf */ + +/* SPCOM register values */ +#define SPCOM_STR (1 << 23) /* Start transmit */ + +#define SPI_PRAM_SIZE 0x100 +#define SPI_MRBLR ((unsigned int)PAGE_SIZE) + +static void *fsl_dummy_rx; +static DEFINE_MUTEX(fsl_dummy_rx_lock); +static int fsl_dummy_rx_refcnt; + +void fsl_spi_cpm_reinit_txrx(struct mpc8xxx_spi *mspi) +{ + if (mspi->flags & SPI_QE) { + qe_issue_cmd(QE_INIT_TX_RX, mspi->subblock, + QE_CR_PROTOCOL_UNSPECIFIED, 0); + } else { + if (mspi->flags & SPI_CPM1) { + out_be32(&mspi->pram->rstate, 0); + out_be16(&mspi->pram->rbptr, + in_be16(&mspi->pram->rbase)); + out_be32(&mspi->pram->tstate, 0); + out_be16(&mspi->pram->tbptr, + in_be16(&mspi->pram->tbase)); + } else { + cpm_command(CPM_SPI_CMD, CPM_CR_INIT_TRX); + } + } +} +EXPORT_SYMBOL_GPL(fsl_spi_cpm_reinit_txrx); + +static void fsl_spi_cpm_bufs_start(struct mpc8xxx_spi *mspi) +{ + struct cpm_buf_desc __iomem *tx_bd = mspi->tx_bd; + struct cpm_buf_desc __iomem *rx_bd = mspi->rx_bd; + unsigned int xfer_len = min(mspi->count, SPI_MRBLR); + unsigned int xfer_ofs; + struct fsl_spi_reg *reg_base = mspi->reg_base; + + xfer_ofs = mspi->xfer_in_progress->len - mspi->count; + + if (mspi->rx_dma == mspi->dma_dummy_rx) + out_be32(&rx_bd->cbd_bufaddr, mspi->rx_dma); + else + out_be32(&rx_bd->cbd_bufaddr, mspi->rx_dma + xfer_ofs); + out_be16(&rx_bd->cbd_datlen, 0); + out_be16(&rx_bd->cbd_sc, BD_SC_EMPTY | BD_SC_INTRPT | BD_SC_WRAP); + + if (mspi->tx_dma == mspi->dma_dummy_tx) + out_be32(&tx_bd->cbd_bufaddr, mspi->tx_dma); + else + out_be32(&tx_bd->cbd_bufaddr, mspi->tx_dma + xfer_ofs); + out_be16(&tx_bd->cbd_datlen, xfer_len); + out_be16(&tx_bd->cbd_sc, BD_SC_READY | BD_SC_INTRPT | BD_SC_WRAP | + BD_SC_LAST); + + /* start transfer */ + mpc8xxx_spi_write_reg(®_base->command, SPCOM_STR); +} + +int fsl_spi_cpm_bufs(struct mpc8xxx_spi *mspi, + struct spi_transfer *t, bool is_dma_mapped) +{ + struct device *dev = mspi->dev; + struct fsl_spi_reg *reg_base = mspi->reg_base; + + if (is_dma_mapped) { + mspi->map_tx_dma = 0; + mspi->map_rx_dma = 0; + } else { + mspi->map_tx_dma = 1; + mspi->map_rx_dma = 1; + } + + if (!t->tx_buf) { + mspi->tx_dma = mspi->dma_dummy_tx; + mspi->map_tx_dma = 0; + } + + if (!t->rx_buf) { + mspi->rx_dma = mspi->dma_dummy_rx; + mspi->map_rx_dma = 0; + } + + if (mspi->map_tx_dma) { + void *nonconst_tx = (void *)mspi->tx; /* shut up gcc */ + + mspi->tx_dma = dma_map_single(dev, nonconst_tx, t->len, + DMA_TO_DEVICE); + if (dma_mapping_error(dev, mspi->tx_dma)) { + dev_err(dev, "unable to map tx dma\n"); + return -ENOMEM; + } + } else if (t->tx_buf) { + mspi->tx_dma = t->tx_dma; + } + + if (mspi->map_rx_dma) { + mspi->rx_dma = dma_map_single(dev, mspi->rx, t->len, + DMA_FROM_DEVICE); + if (dma_mapping_error(dev, mspi->rx_dma)) { + dev_err(dev, "unable to map rx dma\n"); + goto err_rx_dma; + } + } else if (t->rx_buf) { + mspi->rx_dma = t->rx_dma; + } + + /* enable rx ints */ + mpc8xxx_spi_write_reg(®_base->mask, SPIE_RXB); + + mspi->xfer_in_progress = t; + mspi->count = t->len; + + /* start CPM transfers */ + fsl_spi_cpm_bufs_start(mspi); + + return 0; + +err_rx_dma: + if (mspi->map_tx_dma) + dma_unmap_single(dev, mspi->tx_dma, t->len, DMA_TO_DEVICE); + return -ENOMEM; +} +EXPORT_SYMBOL_GPL(fsl_spi_cpm_bufs); + +void fsl_spi_cpm_bufs_complete(struct mpc8xxx_spi *mspi) +{ + struct device *dev = mspi->dev; + struct spi_transfer *t = mspi->xfer_in_progress; + + if (mspi->map_tx_dma) + dma_unmap_single(dev, mspi->tx_dma, t->len, DMA_TO_DEVICE); + if (mspi->map_rx_dma) + dma_unmap_single(dev, mspi->rx_dma, t->len, DMA_FROM_DEVICE); + mspi->xfer_in_progress = NULL; +} +EXPORT_SYMBOL_GPL(fsl_spi_cpm_bufs_complete); + +void fsl_spi_cpm_irq(struct mpc8xxx_spi *mspi, u32 events) +{ + u16 len; + struct fsl_spi_reg *reg_base = mspi->reg_base; + + dev_dbg(mspi->dev, "%s: bd datlen %d, count %d\n", __func__, + in_be16(&mspi->rx_bd->cbd_datlen), mspi->count); + + len = in_be16(&mspi->rx_bd->cbd_datlen); + if (len > mspi->count) { + WARN_ON(1); + len = mspi->count; + } + + /* Clear the events */ + mpc8xxx_spi_write_reg(®_base->event, events); + + mspi->count -= len; + if (mspi->count) + fsl_spi_cpm_bufs_start(mspi); + else + complete(&mspi->done); +} +EXPORT_SYMBOL_GPL(fsl_spi_cpm_irq); + +static void *fsl_spi_alloc_dummy_rx(void) +{ + mutex_lock(&fsl_dummy_rx_lock); + + if (!fsl_dummy_rx) + fsl_dummy_rx = kmalloc(SPI_MRBLR, GFP_KERNEL); + if (fsl_dummy_rx) + fsl_dummy_rx_refcnt++; + + mutex_unlock(&fsl_dummy_rx_lock); + + return fsl_dummy_rx; +} + +static void fsl_spi_free_dummy_rx(void) +{ + mutex_lock(&fsl_dummy_rx_lock); + + switch (fsl_dummy_rx_refcnt) { + case 0: + WARN_ON(1); + break; + case 1: + kfree(fsl_dummy_rx); + fsl_dummy_rx = NULL; + /* fall through */ + default: + fsl_dummy_rx_refcnt--; + break; + } + + mutex_unlock(&fsl_dummy_rx_lock); +} + +static unsigned long fsl_spi_cpm_get_pram(struct mpc8xxx_spi *mspi) +{ + struct device *dev = mspi->dev; + struct device_node *np = dev->of_node; + const u32 *iprop; + int size; + void __iomem *spi_base; + unsigned long pram_ofs = -ENOMEM; + + /* Can't use of_address_to_resource(), QE muram isn't at 0. */ + iprop = of_get_property(np, "reg", &size); + + /* QE with a fixed pram location? */ + if (mspi->flags & SPI_QE && iprop && size == sizeof(*iprop) * 4) + return cpm_muram_alloc_fixed(iprop[2], SPI_PRAM_SIZE); + + /* QE but with a dynamic pram location? */ + if (mspi->flags & SPI_QE) { + pram_ofs = cpm_muram_alloc(SPI_PRAM_SIZE, 64); + qe_issue_cmd(QE_ASSIGN_PAGE_TO_DEVICE, mspi->subblock, + QE_CR_PROTOCOL_UNSPECIFIED, pram_ofs); + return pram_ofs; + } + + spi_base = of_iomap(np, 1); + if (spi_base == NULL) + return -EINVAL; + + if (mspi->flags & SPI_CPM2) { + pram_ofs = cpm_muram_alloc(SPI_PRAM_SIZE, 64); + out_be16(spi_base, pram_ofs); + } + + iounmap(spi_base); + return pram_ofs; +} + +int fsl_spi_cpm_init(struct mpc8xxx_spi *mspi) +{ + struct device *dev = mspi->dev; + struct device_node *np = dev->of_node; + const u32 *iprop; + int size; + unsigned long bds_ofs; + + if (!(mspi->flags & SPI_CPM_MODE)) + return 0; + + if (!fsl_spi_alloc_dummy_rx()) + return -ENOMEM; + + if (mspi->flags & SPI_QE) { + iprop = of_get_property(np, "cell-index", &size); + if (iprop && size == sizeof(*iprop)) + mspi->subblock = *iprop; + + switch (mspi->subblock) { + default: + dev_warn(dev, "cell-index unspecified, assuming SPI1\n"); + /* fall through */ + case 0: + mspi->subblock = QE_CR_SUBBLOCK_SPI1; + break; + case 1: + mspi->subblock = QE_CR_SUBBLOCK_SPI2; + break; + } + } + + if (mspi->flags & SPI_CPM1) { + struct resource *res; + void *pram; + + res = platform_get_resource(to_platform_device(dev), + IORESOURCE_MEM, 1); + pram = devm_ioremap_resource(dev, res); + if (IS_ERR(pram)) + mspi->pram = NULL; + else + mspi->pram = pram; + } else { + unsigned long pram_ofs = fsl_spi_cpm_get_pram(mspi); + + if (IS_ERR_VALUE(pram_ofs)) + mspi->pram = NULL; + else + mspi->pram = cpm_muram_addr(pram_ofs); + } + if (mspi->pram == NULL) { + dev_err(dev, "can't allocate spi parameter ram\n"); + goto err_pram; + } + + bds_ofs = cpm_muram_alloc(sizeof(*mspi->tx_bd) + + sizeof(*mspi->rx_bd), 8); + if (IS_ERR_VALUE(bds_ofs)) { + dev_err(dev, "can't allocate bds\n"); + goto err_bds; + } + + mspi->dma_dummy_tx = dma_map_single(dev, empty_zero_page, PAGE_SIZE, + DMA_TO_DEVICE); + if (dma_mapping_error(dev, mspi->dma_dummy_tx)) { + dev_err(dev, "unable to map dummy tx buffer\n"); + goto err_dummy_tx; + } + + mspi->dma_dummy_rx = dma_map_single(dev, fsl_dummy_rx, SPI_MRBLR, + DMA_FROM_DEVICE); + if (dma_mapping_error(dev, mspi->dma_dummy_rx)) { + dev_err(dev, "unable to map dummy rx buffer\n"); + goto err_dummy_rx; + } + + mspi->tx_bd = cpm_muram_addr(bds_ofs); + mspi->rx_bd = cpm_muram_addr(bds_ofs + sizeof(*mspi->tx_bd)); + + /* Initialize parameter ram. */ + out_be16(&mspi->pram->tbase, cpm_muram_offset(mspi->tx_bd)); + out_be16(&mspi->pram->rbase, cpm_muram_offset(mspi->rx_bd)); + out_8(&mspi->pram->tfcr, CPMFCR_EB | CPMFCR_GBL); + out_8(&mspi->pram->rfcr, CPMFCR_EB | CPMFCR_GBL); + out_be16(&mspi->pram->mrblr, SPI_MRBLR); + out_be32(&mspi->pram->rstate, 0); + out_be32(&mspi->pram->rdp, 0); + out_be16(&mspi->pram->rbptr, 0); + out_be16(&mspi->pram->rbc, 0); + out_be32(&mspi->pram->rxtmp, 0); + out_be32(&mspi->pram->tstate, 0); + out_be32(&mspi->pram->tdp, 0); + out_be16(&mspi->pram->tbptr, 0); + out_be16(&mspi->pram->tbc, 0); + out_be32(&mspi->pram->txtmp, 0); + + return 0; + +err_dummy_rx: + dma_unmap_single(dev, mspi->dma_dummy_tx, PAGE_SIZE, DMA_TO_DEVICE); +err_dummy_tx: + cpm_muram_free(bds_ofs); +err_bds: + if (!(mspi->flags & SPI_CPM1)) + cpm_muram_free(cpm_muram_offset(mspi->pram)); +err_pram: + fsl_spi_free_dummy_rx(); + return -ENOMEM; +} +EXPORT_SYMBOL_GPL(fsl_spi_cpm_init); + +void fsl_spi_cpm_free(struct mpc8xxx_spi *mspi) +{ + struct device *dev = mspi->dev; + + if (!(mspi->flags & SPI_CPM_MODE)) + return; + + dma_unmap_single(dev, mspi->dma_dummy_rx, SPI_MRBLR, DMA_FROM_DEVICE); + dma_unmap_single(dev, mspi->dma_dummy_tx, PAGE_SIZE, DMA_TO_DEVICE); + cpm_muram_free(cpm_muram_offset(mspi->tx_bd)); + cpm_muram_free(cpm_muram_offset(mspi->pram)); + fsl_spi_free_dummy_rx(); +} +EXPORT_SYMBOL_GPL(fsl_spi_cpm_free); + +MODULE_LICENSE("GPL"); diff --git a/drivers/spi/spi-fsl-cpm.h b/drivers/spi/spi-fsl-cpm.h new file mode 100644 index 000000000..c71115805 --- /dev/null +++ b/drivers/spi/spi-fsl-cpm.h @@ -0,0 +1,43 @@ +/* + * Freescale SPI controller driver cpm functions. + * + * Maintainer: Kumar Gala + * + * Copyright (C) 2006 Polycom, Inc. + * Copyright 2010 Freescale Semiconductor, Inc. + * + * CPM SPI and QE buffer descriptors mode support: + * Copyright (c) 2009 MontaVista Software, Inc. + * Author: Anton Vorontsov <avorontsov@ru.mvista.com> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + */ + +#ifndef __SPI_FSL_CPM_H__ +#define __SPI_FSL_CPM_H__ + +#include "spi-fsl-lib.h" + +#ifdef CONFIG_FSL_SOC +extern void fsl_spi_cpm_reinit_txrx(struct mpc8xxx_spi *mspi); +extern int fsl_spi_cpm_bufs(struct mpc8xxx_spi *mspi, + struct spi_transfer *t, bool is_dma_mapped); +extern void fsl_spi_cpm_bufs_complete(struct mpc8xxx_spi *mspi); +extern void fsl_spi_cpm_irq(struct mpc8xxx_spi *mspi, u32 events); +extern int fsl_spi_cpm_init(struct mpc8xxx_spi *mspi); +extern void fsl_spi_cpm_free(struct mpc8xxx_spi *mspi); +#else +static inline void fsl_spi_cpm_reinit_txrx(struct mpc8xxx_spi *mspi) { } +static inline int fsl_spi_cpm_bufs(struct mpc8xxx_spi *mspi, + struct spi_transfer *t, + bool is_dma_mapped) { return 0; } +static inline void fsl_spi_cpm_bufs_complete(struct mpc8xxx_spi *mspi) { } +static inline void fsl_spi_cpm_irq(struct mpc8xxx_spi *mspi, u32 events) { } +static inline int fsl_spi_cpm_init(struct mpc8xxx_spi *mspi) { return 0; } +static inline void fsl_spi_cpm_free(struct mpc8xxx_spi *mspi) { } +#endif + +#endif /* __SPI_FSL_CPM_H__ */ diff --git a/drivers/spi/spi-fsl-dspi.c b/drivers/spi/spi-fsl-dspi.c new file mode 100644 index 000000000..5fe54cda3 --- /dev/null +++ b/drivers/spi/spi-fsl-dspi.c @@ -0,0 +1,643 @@ +/* + * drivers/spi/spi-fsl-dspi.c + * + * Copyright 2013 Freescale Semiconductor, Inc. + * + * Freescale DSPI driver + * This file contains a driver for the Freescale DSPI + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + */ + +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/err.h> +#include <linux/errno.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/math64.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/regmap.h> +#include <linux/sched.h> +#include <linux/spi/spi.h> +#include <linux/spi/spi_bitbang.h> +#include <linux/time.h> + +#define DRIVER_NAME "fsl-dspi" + +#define TRAN_STATE_RX_VOID 0x01 +#define TRAN_STATE_TX_VOID 0x02 +#define TRAN_STATE_WORD_ODD_NUM 0x04 + +#define DSPI_FIFO_SIZE 4 + +#define SPI_MCR 0x00 +#define SPI_MCR_MASTER (1 << 31) +#define SPI_MCR_PCSIS (0x3F << 16) +#define SPI_MCR_CLR_TXF (1 << 11) +#define SPI_MCR_CLR_RXF (1 << 10) + +#define SPI_TCR 0x08 + +#define SPI_CTAR(x) (0x0c + (((x) & 0x3) * 4)) +#define SPI_CTAR_FMSZ(x) (((x) & 0x0000000f) << 27) +#define SPI_CTAR_CPOL(x) ((x) << 26) +#define SPI_CTAR_CPHA(x) ((x) << 25) +#define SPI_CTAR_LSBFE(x) ((x) << 24) +#define SPI_CTAR_PCSSCK(x) (((x) & 0x00000003) << 22) +#define SPI_CTAR_PASC(x) (((x) & 0x00000003) << 20) +#define SPI_CTAR_PDT(x) (((x) & 0x00000003) << 18) +#define SPI_CTAR_PBR(x) (((x) & 0x00000003) << 16) +#define SPI_CTAR_CSSCK(x) (((x) & 0x0000000f) << 12) +#define SPI_CTAR_ASC(x) (((x) & 0x0000000f) << 8) +#define SPI_CTAR_DT(x) (((x) & 0x0000000f) << 4) +#define SPI_CTAR_BR(x) ((x) & 0x0000000f) +#define SPI_CTAR_SCALE_BITS 0xf + +#define SPI_CTAR0_SLAVE 0x0c + +#define SPI_SR 0x2c +#define SPI_SR_EOQF 0x10000000 + +#define SPI_RSER 0x30 +#define SPI_RSER_EOQFE 0x10000000 + +#define SPI_PUSHR 0x34 +#define SPI_PUSHR_CONT (1 << 31) +#define SPI_PUSHR_CTAS(x) (((x) & 0x00000003) << 28) +#define SPI_PUSHR_EOQ (1 << 27) +#define SPI_PUSHR_CTCNT (1 << 26) +#define SPI_PUSHR_PCS(x) (((1 << x) & 0x0000003f) << 16) +#define SPI_PUSHR_TXDATA(x) ((x) & 0x0000ffff) + +#define SPI_PUSHR_SLAVE 0x34 + +#define SPI_POPR 0x38 +#define SPI_POPR_RXDATA(x) ((x) & 0x0000ffff) + +#define SPI_TXFR0 0x3c +#define SPI_TXFR1 0x40 +#define SPI_TXFR2 0x44 +#define SPI_TXFR3 0x48 +#define SPI_RXFR0 0x7c +#define SPI_RXFR1 0x80 +#define SPI_RXFR2 0x84 +#define SPI_RXFR3 0x88 + +#define SPI_FRAME_BITS(bits) SPI_CTAR_FMSZ((bits) - 1) +#define SPI_FRAME_BITS_MASK SPI_CTAR_FMSZ(0xf) +#define SPI_FRAME_BITS_16 SPI_CTAR_FMSZ(0xf) +#define SPI_FRAME_BITS_8 SPI_CTAR_FMSZ(0x7) + +#define SPI_CS_INIT 0x01 +#define SPI_CS_ASSERT 0x02 +#define SPI_CS_DROP 0x04 + +struct chip_data { + u32 mcr_val; + u32 ctar_val; + u16 void_write_data; +}; + +struct fsl_dspi { + struct spi_master *master; + struct platform_device *pdev; + + struct regmap *regmap; + int irq; + struct clk *clk; + + struct spi_transfer *cur_transfer; + struct spi_message *cur_msg; + struct chip_data *cur_chip; + size_t len; + void *tx; + void *tx_end; + void *rx; + void *rx_end; + char dataflags; + u8 cs; + u16 void_write_data; + u32 cs_change; + + wait_queue_head_t waitq; + u32 waitflags; +}; + +static inline int is_double_byte_mode(struct fsl_dspi *dspi) +{ + unsigned int val; + + regmap_read(dspi->regmap, SPI_CTAR(dspi->cs), &val); + + return ((val & SPI_FRAME_BITS_MASK) == SPI_FRAME_BITS(8)) ? 0 : 1; +} + +static void hz_to_spi_baud(char *pbr, char *br, int speed_hz, + unsigned long clkrate) +{ + /* Valid baud rate pre-scaler values */ + int pbr_tbl[4] = {2, 3, 5, 7}; + int brs[16] = { 2, 4, 6, 8, + 16, 32, 64, 128, + 256, 512, 1024, 2048, + 4096, 8192, 16384, 32768 }; + int scale_needed, scale, minscale = INT_MAX; + int i, j; + + scale_needed = clkrate / speed_hz; + if (clkrate % speed_hz) + scale_needed++; + + for (i = 0; i < ARRAY_SIZE(brs); i++) + for (j = 0; j < ARRAY_SIZE(pbr_tbl); j++) { + scale = brs[i] * pbr_tbl[j]; + if (scale >= scale_needed) { + if (scale < minscale) { + minscale = scale; + *br = i; + *pbr = j; + } + break; + } + } + + if (minscale == INT_MAX) { + pr_warn("Can not find valid baud rate,speed_hz is %d,clkrate is %ld, we use the max prescaler value.\n", + speed_hz, clkrate); + *pbr = ARRAY_SIZE(pbr_tbl) - 1; + *br = ARRAY_SIZE(brs) - 1; + } +} + +static void ns_delay_scale(char *psc, char *sc, int delay_ns, + unsigned long clkrate) +{ + int pscale_tbl[4] = {1, 3, 5, 7}; + int scale_needed, scale, minscale = INT_MAX; + int i, j; + u32 remainder; + + scale_needed = div_u64_rem((u64)delay_ns * clkrate, NSEC_PER_SEC, + &remainder); + if (remainder) + scale_needed++; + + for (i = 0; i < ARRAY_SIZE(pscale_tbl); i++) + for (j = 0; j <= SPI_CTAR_SCALE_BITS; j++) { + scale = pscale_tbl[i] * (2 << j); + if (scale >= scale_needed) { + if (scale < minscale) { + minscale = scale; + *psc = i; + *sc = j; + } + break; + } + } + + if (minscale == INT_MAX) { + pr_warn("Cannot find correct scale values for %dns delay at clkrate %ld, using max prescaler value", + delay_ns, clkrate); + *psc = ARRAY_SIZE(pscale_tbl) - 1; + *sc = SPI_CTAR_SCALE_BITS; + } +} + +static int dspi_transfer_write(struct fsl_dspi *dspi) +{ + int tx_count = 0; + int tx_word; + u16 d16; + u8 d8; + u32 dspi_pushr = 0; + int first = 1; + + tx_word = is_double_byte_mode(dspi); + + /* If we are in word mode, but only have a single byte to transfer + * then switch to byte mode temporarily. Will switch back at the + * end of the transfer. + */ + if (tx_word && (dspi->len == 1)) { + dspi->dataflags |= TRAN_STATE_WORD_ODD_NUM; + regmap_update_bits(dspi->regmap, SPI_CTAR(dspi->cs), + SPI_FRAME_BITS_MASK, SPI_FRAME_BITS(8)); + tx_word = 0; + } + + while (dspi->len && (tx_count < DSPI_FIFO_SIZE)) { + if (tx_word) { + if (dspi->len == 1) + break; + + if (!(dspi->dataflags & TRAN_STATE_TX_VOID)) { + d16 = *(u16 *)dspi->tx; + dspi->tx += 2; + } else { + d16 = dspi->void_write_data; + } + + dspi_pushr = SPI_PUSHR_TXDATA(d16) | + SPI_PUSHR_PCS(dspi->cs) | + SPI_PUSHR_CTAS(dspi->cs) | + SPI_PUSHR_CONT; + + dspi->len -= 2; + } else { + if (!(dspi->dataflags & TRAN_STATE_TX_VOID)) { + + d8 = *(u8 *)dspi->tx; + dspi->tx++; + } else { + d8 = (u8)dspi->void_write_data; + } + + dspi_pushr = SPI_PUSHR_TXDATA(d8) | + SPI_PUSHR_PCS(dspi->cs) | + SPI_PUSHR_CTAS(dspi->cs) | + SPI_PUSHR_CONT; + + dspi->len--; + } + + if (dspi->len == 0 || tx_count == DSPI_FIFO_SIZE - 1) { + /* last transfer in the transfer */ + dspi_pushr |= SPI_PUSHR_EOQ; + if ((dspi->cs_change) && (!dspi->len)) + dspi_pushr &= ~SPI_PUSHR_CONT; + } else if (tx_word && (dspi->len == 1)) + dspi_pushr |= SPI_PUSHR_EOQ; + + if (first) { + first = 0; + dspi_pushr |= SPI_PUSHR_CTCNT; /* clear counter */ + } + + regmap_write(dspi->regmap, SPI_PUSHR, dspi_pushr); + + tx_count++; + } + + return tx_count * (tx_word + 1); +} + +static int dspi_transfer_read(struct fsl_dspi *dspi) +{ + int rx_count = 0; + int rx_word = is_double_byte_mode(dspi); + u16 d; + + while ((dspi->rx < dspi->rx_end) + && (rx_count < DSPI_FIFO_SIZE)) { + if (rx_word) { + unsigned int val; + + if ((dspi->rx_end - dspi->rx) == 1) + break; + + regmap_read(dspi->regmap, SPI_POPR, &val); + d = SPI_POPR_RXDATA(val); + + if (!(dspi->dataflags & TRAN_STATE_RX_VOID)) + *(u16 *)dspi->rx = d; + dspi->rx += 2; + + } else { + unsigned int val; + + regmap_read(dspi->regmap, SPI_POPR, &val); + d = SPI_POPR_RXDATA(val); + if (!(dspi->dataflags & TRAN_STATE_RX_VOID)) + *(u8 *)dspi->rx = d; + dspi->rx++; + } + rx_count++; + } + + return rx_count; +} + +static int dspi_transfer_one_message(struct spi_master *master, + struct spi_message *message) +{ + struct fsl_dspi *dspi = spi_master_get_devdata(master); + struct spi_device *spi = message->spi; + struct spi_transfer *transfer; + int status = 0; + message->actual_length = 0; + + list_for_each_entry(transfer, &message->transfers, transfer_list) { + dspi->cur_transfer = transfer; + dspi->cur_msg = message; + dspi->cur_chip = spi_get_ctldata(spi); + dspi->cs = spi->chip_select; + if (dspi->cur_transfer->transfer_list.next + == &dspi->cur_msg->transfers) + transfer->cs_change = 1; + dspi->cs_change = transfer->cs_change; + dspi->void_write_data = dspi->cur_chip->void_write_data; + + dspi->dataflags = 0; + dspi->tx = (void *)transfer->tx_buf; + dspi->tx_end = dspi->tx + transfer->len; + dspi->rx = transfer->rx_buf; + dspi->rx_end = dspi->rx + transfer->len; + dspi->len = transfer->len; + + if (!dspi->rx) + dspi->dataflags |= TRAN_STATE_RX_VOID; + + if (!dspi->tx) + dspi->dataflags |= TRAN_STATE_TX_VOID; + + regmap_write(dspi->regmap, SPI_MCR, dspi->cur_chip->mcr_val); + regmap_update_bits(dspi->regmap, SPI_MCR, + SPI_MCR_CLR_TXF | SPI_MCR_CLR_RXF, + SPI_MCR_CLR_TXF | SPI_MCR_CLR_RXF); + regmap_write(dspi->regmap, SPI_CTAR(dspi->cs), + dspi->cur_chip->ctar_val); + if (transfer->speed_hz) + regmap_write(dspi->regmap, SPI_CTAR(dspi->cs), + dspi->cur_chip->ctar_val); + + regmap_write(dspi->regmap, SPI_RSER, SPI_RSER_EOQFE); + message->actual_length += dspi_transfer_write(dspi); + + if (wait_event_interruptible(dspi->waitq, dspi->waitflags)) + dev_err(&dspi->pdev->dev, "wait transfer complete fail!\n"); + dspi->waitflags = 0; + + if (transfer->delay_usecs) + udelay(transfer->delay_usecs); + } + + message->status = status; + spi_finalize_current_message(master); + + return status; +} + +static int dspi_setup(struct spi_device *spi) +{ + struct chip_data *chip; + struct fsl_dspi *dspi = spi_master_get_devdata(spi->master); + u32 cs_sck_delay = 0, sck_cs_delay = 0; + unsigned char br = 0, pbr = 0, pcssck = 0, cssck = 0; + unsigned char pasc = 0, asc = 0, fmsz = 0; + unsigned long clkrate; + + if ((spi->bits_per_word >= 4) && (spi->bits_per_word <= 16)) { + fmsz = spi->bits_per_word - 1; + } else { + pr_err("Invalid wordsize\n"); + return -ENODEV; + } + + /* Only alloc on first setup */ + chip = spi_get_ctldata(spi); + if (chip == NULL) { + chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL); + if (!chip) + return -ENOMEM; + } + + of_property_read_u32(spi->dev.of_node, "fsl,spi-cs-sck-delay", + &cs_sck_delay); + + of_property_read_u32(spi->dev.of_node, "fsl,spi-sck-cs-delay", + &sck_cs_delay); + + chip->mcr_val = SPI_MCR_MASTER | SPI_MCR_PCSIS | + SPI_MCR_CLR_TXF | SPI_MCR_CLR_RXF; + + chip->void_write_data = 0; + + clkrate = clk_get_rate(dspi->clk); + hz_to_spi_baud(&pbr, &br, spi->max_speed_hz, clkrate); + + /* Set PCS to SCK delay scale values */ + ns_delay_scale(&pcssck, &cssck, cs_sck_delay, clkrate); + + /* Set After SCK delay scale values */ + ns_delay_scale(&pasc, &asc, sck_cs_delay, clkrate); + + chip->ctar_val = SPI_CTAR_FMSZ(fmsz) + | SPI_CTAR_CPOL(spi->mode & SPI_CPOL ? 1 : 0) + | SPI_CTAR_CPHA(spi->mode & SPI_CPHA ? 1 : 0) + | SPI_CTAR_LSBFE(spi->mode & SPI_LSB_FIRST ? 1 : 0) + | SPI_CTAR_PCSSCK(pcssck) + | SPI_CTAR_CSSCK(cssck) + | SPI_CTAR_PASC(pasc) + | SPI_CTAR_ASC(asc) + | SPI_CTAR_PBR(pbr) + | SPI_CTAR_BR(br); + + spi_set_ctldata(spi, chip); + + return 0; +} + +static void dspi_cleanup(struct spi_device *spi) +{ + struct chip_data *chip = spi_get_ctldata((struct spi_device *)spi); + + dev_dbg(&spi->dev, "spi_device %u.%u cleanup\n", + spi->master->bus_num, spi->chip_select); + + kfree(chip); +} + +static irqreturn_t dspi_interrupt(int irq, void *dev_id) +{ + struct fsl_dspi *dspi = (struct fsl_dspi *)dev_id; + + struct spi_message *msg = dspi->cur_msg; + + regmap_write(dspi->regmap, SPI_SR, SPI_SR_EOQF); + dspi_transfer_read(dspi); + + if (!dspi->len) { + if (dspi->dataflags & TRAN_STATE_WORD_ODD_NUM) + regmap_update_bits(dspi->regmap, SPI_CTAR(dspi->cs), + SPI_FRAME_BITS_MASK, SPI_FRAME_BITS(16)); + + dspi->waitflags = 1; + wake_up_interruptible(&dspi->waitq); + } else + msg->actual_length += dspi_transfer_write(dspi); + + return IRQ_HANDLED; +} + +static const struct of_device_id fsl_dspi_dt_ids[] = { + { .compatible = "fsl,vf610-dspi", .data = NULL, }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, fsl_dspi_dt_ids); + +#ifdef CONFIG_PM_SLEEP +static int dspi_suspend(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct fsl_dspi *dspi = spi_master_get_devdata(master); + + spi_master_suspend(master); + clk_disable_unprepare(dspi->clk); + + return 0; +} + +static int dspi_resume(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct fsl_dspi *dspi = spi_master_get_devdata(master); + + clk_prepare_enable(dspi->clk); + spi_master_resume(master); + + return 0; +} +#endif /* CONFIG_PM_SLEEP */ + +static SIMPLE_DEV_PM_OPS(dspi_pm, dspi_suspend, dspi_resume); + +static const struct regmap_config dspi_regmap_config = { + .reg_bits = 32, + .val_bits = 32, + .reg_stride = 4, + .max_register = 0x88, +}; + +static int dspi_probe(struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + struct spi_master *master; + struct fsl_dspi *dspi; + struct resource *res; + void __iomem *base; + int ret = 0, cs_num, bus_num; + + master = spi_alloc_master(&pdev->dev, sizeof(struct fsl_dspi)); + if (!master) + return -ENOMEM; + + dspi = spi_master_get_devdata(master); + dspi->pdev = pdev; + dspi->master = master; + + master->transfer = NULL; + master->setup = dspi_setup; + master->transfer_one_message = dspi_transfer_one_message; + master->dev.of_node = pdev->dev.of_node; + + master->cleanup = dspi_cleanup; + master->mode_bits = SPI_CPOL | SPI_CPHA; + master->bits_per_word_mask = SPI_BPW_MASK(4) | SPI_BPW_MASK(8) | + SPI_BPW_MASK(16); + + ret = of_property_read_u32(np, "spi-num-chipselects", &cs_num); + if (ret < 0) { + dev_err(&pdev->dev, "can't get spi-num-chipselects\n"); + goto out_master_put; + } + master->num_chipselect = cs_num; + + ret = of_property_read_u32(np, "bus-num", &bus_num); + if (ret < 0) { + dev_err(&pdev->dev, "can't get bus-num\n"); + goto out_master_put; + } + master->bus_num = bus_num; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(base)) { + ret = PTR_ERR(base); + goto out_master_put; + } + + dspi->regmap = devm_regmap_init_mmio_clk(&pdev->dev, "dspi", base, + &dspi_regmap_config); + if (IS_ERR(dspi->regmap)) { + dev_err(&pdev->dev, "failed to init regmap: %ld\n", + PTR_ERR(dspi->regmap)); + return PTR_ERR(dspi->regmap); + } + + dspi->irq = platform_get_irq(pdev, 0); + if (dspi->irq < 0) { + dev_err(&pdev->dev, "can't get platform irq\n"); + ret = dspi->irq; + goto out_master_put; + } + + ret = devm_request_irq(&pdev->dev, dspi->irq, dspi_interrupt, 0, + pdev->name, dspi); + if (ret < 0) { + dev_err(&pdev->dev, "Unable to attach DSPI interrupt\n"); + goto out_master_put; + } + + dspi->clk = devm_clk_get(&pdev->dev, "dspi"); + if (IS_ERR(dspi->clk)) { + ret = PTR_ERR(dspi->clk); + dev_err(&pdev->dev, "unable to get clock\n"); + goto out_master_put; + } + clk_prepare_enable(dspi->clk); + + init_waitqueue_head(&dspi->waitq); + platform_set_drvdata(pdev, master); + + ret = spi_register_master(master); + if (ret != 0) { + dev_err(&pdev->dev, "Problem registering DSPI master\n"); + goto out_clk_put; + } + + return ret; + +out_clk_put: + clk_disable_unprepare(dspi->clk); +out_master_put: + spi_master_put(master); + + return ret; +} + +static int dspi_remove(struct platform_device *pdev) +{ + struct spi_master *master = platform_get_drvdata(pdev); + struct fsl_dspi *dspi = spi_master_get_devdata(master); + + /* Disconnect from the SPI framework */ + clk_disable_unprepare(dspi->clk); + spi_unregister_master(dspi->master); + spi_master_put(dspi->master); + + return 0; +} + +static struct platform_driver fsl_dspi_driver = { + .driver.name = DRIVER_NAME, + .driver.of_match_table = fsl_dspi_dt_ids, + .driver.owner = THIS_MODULE, + .driver.pm = &dspi_pm, + .probe = dspi_probe, + .remove = dspi_remove, +}; +module_platform_driver(fsl_dspi_driver); + +MODULE_DESCRIPTION("Freescale DSPI Controller Driver"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:" DRIVER_NAME); diff --git a/drivers/spi/spi-fsl-espi.c b/drivers/spi/spi-fsl-espi.c new file mode 100644 index 000000000..80d245ac8 --- /dev/null +++ b/drivers/spi/spi-fsl-espi.c @@ -0,0 +1,880 @@ +/* + * Freescale eSPI controller driver. + * + * Copyright 2010 Freescale Semiconductor, Inc. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + */ +#include <linux/delay.h> +#include <linux/err.h> +#include <linux/fsl_devices.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/module.h> +#include <linux/mm.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/of_platform.h> +#include <linux/platform_device.h> +#include <linux/spi/spi.h> +#include <sysdev/fsl_soc.h> + +#include "spi-fsl-lib.h" + +/* eSPI Controller registers */ +struct fsl_espi_reg { + __be32 mode; /* 0x000 - eSPI mode register */ + __be32 event; /* 0x004 - eSPI event register */ + __be32 mask; /* 0x008 - eSPI mask register */ + __be32 command; /* 0x00c - eSPI command register */ + __be32 transmit; /* 0x010 - eSPI transmit FIFO access register*/ + __be32 receive; /* 0x014 - eSPI receive FIFO access register*/ + u8 res[8]; /* 0x018 - 0x01c reserved */ + __be32 csmode[4]; /* 0x020 - 0x02c eSPI cs mode register */ +}; + +struct fsl_espi_transfer { + const void *tx_buf; + void *rx_buf; + unsigned len; + unsigned n_tx; + unsigned n_rx; + unsigned actual_length; + int status; +}; + +/* eSPI Controller mode register definitions */ +#define SPMODE_ENABLE (1 << 31) +#define SPMODE_LOOP (1 << 30) +#define SPMODE_TXTHR(x) ((x) << 8) +#define SPMODE_RXTHR(x) ((x) << 0) + +/* eSPI Controller CS mode register definitions */ +#define CSMODE_CI_INACTIVEHIGH (1 << 31) +#define CSMODE_CP_BEGIN_EDGECLK (1 << 30) +#define CSMODE_REV (1 << 29) +#define CSMODE_DIV16 (1 << 28) +#define CSMODE_PM(x) ((x) << 24) +#define CSMODE_POL_1 (1 << 20) +#define CSMODE_LEN(x) ((x) << 16) +#define CSMODE_BEF(x) ((x) << 12) +#define CSMODE_AFT(x) ((x) << 8) +#define CSMODE_CG(x) ((x) << 3) + +/* Default mode/csmode for eSPI controller */ +#define SPMODE_INIT_VAL (SPMODE_TXTHR(4) | SPMODE_RXTHR(3)) +#define CSMODE_INIT_VAL (CSMODE_POL_1 | CSMODE_BEF(0) \ + | CSMODE_AFT(0) | CSMODE_CG(1)) + +/* SPIE register values */ +#define SPIE_NE 0x00000200 /* Not empty */ +#define SPIE_NF 0x00000100 /* Not full */ + +/* SPIM register values */ +#define SPIM_NE 0x00000200 /* Not empty */ +#define SPIM_NF 0x00000100 /* Not full */ +#define SPIE_RXCNT(reg) ((reg >> 24) & 0x3F) +#define SPIE_TXCNT(reg) ((reg >> 16) & 0x3F) + +/* SPCOM register values */ +#define SPCOM_CS(x) ((x) << 30) +#define SPCOM_TRANLEN(x) ((x) << 0) +#define SPCOM_TRANLEN_MAX 0xFFFF /* Max transaction length */ + +static void fsl_espi_change_mode(struct spi_device *spi) +{ + struct mpc8xxx_spi *mspi = spi_master_get_devdata(spi->master); + struct spi_mpc8xxx_cs *cs = spi->controller_state; + struct fsl_espi_reg *reg_base = mspi->reg_base; + __be32 __iomem *mode = ®_base->csmode[spi->chip_select]; + __be32 __iomem *espi_mode = ®_base->mode; + u32 tmp; + unsigned long flags; + + /* Turn off IRQs locally to minimize time that SPI is disabled. */ + local_irq_save(flags); + + /* Turn off SPI unit prior changing mode */ + tmp = mpc8xxx_spi_read_reg(espi_mode); + mpc8xxx_spi_write_reg(espi_mode, tmp & ~SPMODE_ENABLE); + mpc8xxx_spi_write_reg(mode, cs->hw_mode); + mpc8xxx_spi_write_reg(espi_mode, tmp); + + local_irq_restore(flags); +} + +static u32 fsl_espi_tx_buf_lsb(struct mpc8xxx_spi *mpc8xxx_spi) +{ + u32 data; + u16 data_h; + u16 data_l; + const u32 *tx = mpc8xxx_spi->tx; + + if (!tx) + return 0; + + data = *tx++ << mpc8xxx_spi->tx_shift; + data_l = data & 0xffff; + data_h = (data >> 16) & 0xffff; + swab16s(&data_l); + swab16s(&data_h); + data = data_h | data_l; + + mpc8xxx_spi->tx = tx; + return data; +} + +static int fsl_espi_setup_transfer(struct spi_device *spi, + struct spi_transfer *t) +{ + struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master); + int bits_per_word = 0; + u8 pm; + u32 hz = 0; + struct spi_mpc8xxx_cs *cs = spi->controller_state; + + if (t) { + bits_per_word = t->bits_per_word; + hz = t->speed_hz; + } + + /* spi_transfer level calls that work per-word */ + if (!bits_per_word) + bits_per_word = spi->bits_per_word; + + if (!hz) + hz = spi->max_speed_hz; + + cs->rx_shift = 0; + cs->tx_shift = 0; + cs->get_rx = mpc8xxx_spi_rx_buf_u32; + cs->get_tx = mpc8xxx_spi_tx_buf_u32; + if (bits_per_word <= 8) { + cs->rx_shift = 8 - bits_per_word; + } else { + cs->rx_shift = 16 - bits_per_word; + if (spi->mode & SPI_LSB_FIRST) + cs->get_tx = fsl_espi_tx_buf_lsb; + } + + mpc8xxx_spi->rx_shift = cs->rx_shift; + mpc8xxx_spi->tx_shift = cs->tx_shift; + mpc8xxx_spi->get_rx = cs->get_rx; + mpc8xxx_spi->get_tx = cs->get_tx; + + bits_per_word = bits_per_word - 1; + + /* mask out bits we are going to set */ + cs->hw_mode &= ~(CSMODE_LEN(0xF) | CSMODE_DIV16 | CSMODE_PM(0xF)); + + cs->hw_mode |= CSMODE_LEN(bits_per_word); + + if ((mpc8xxx_spi->spibrg / hz) > 64) { + cs->hw_mode |= CSMODE_DIV16; + pm = DIV_ROUND_UP(mpc8xxx_spi->spibrg, hz * 16 * 4); + + WARN_ONCE(pm > 33, "%s: Requested speed is too low: %d Hz. " + "Will use %d Hz instead.\n", dev_name(&spi->dev), + hz, mpc8xxx_spi->spibrg / (4 * 16 * (32 + 1))); + if (pm > 33) + pm = 33; + } else { + pm = DIV_ROUND_UP(mpc8xxx_spi->spibrg, hz * 4); + } + if (pm) + pm--; + if (pm < 2) + pm = 2; + + cs->hw_mode |= CSMODE_PM(pm); + + fsl_espi_change_mode(spi); + return 0; +} + +static int fsl_espi_cpu_bufs(struct mpc8xxx_spi *mspi, struct spi_transfer *t, + unsigned int len) +{ + u32 word; + struct fsl_espi_reg *reg_base = mspi->reg_base; + + mspi->count = len; + + /* enable rx ints */ + mpc8xxx_spi_write_reg(®_base->mask, SPIM_NE); + + /* transmit word */ + word = mspi->get_tx(mspi); + mpc8xxx_spi_write_reg(®_base->transmit, word); + + return 0; +} + +static int fsl_espi_bufs(struct spi_device *spi, struct spi_transfer *t) +{ + struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master); + struct fsl_espi_reg *reg_base = mpc8xxx_spi->reg_base; + unsigned int len = t->len; + int ret; + + mpc8xxx_spi->len = t->len; + len = roundup(len, 4) / 4; + + mpc8xxx_spi->tx = t->tx_buf; + mpc8xxx_spi->rx = t->rx_buf; + + reinit_completion(&mpc8xxx_spi->done); + + /* Set SPCOM[CS] and SPCOM[TRANLEN] field */ + if ((t->len - 1) > SPCOM_TRANLEN_MAX) { + dev_err(mpc8xxx_spi->dev, "Transaction length (%d)" + " beyond the SPCOM[TRANLEN] field\n", t->len); + return -EINVAL; + } + mpc8xxx_spi_write_reg(®_base->command, + (SPCOM_CS(spi->chip_select) | SPCOM_TRANLEN(t->len - 1))); + + ret = fsl_espi_cpu_bufs(mpc8xxx_spi, t, len); + if (ret) + return ret; + + wait_for_completion(&mpc8xxx_spi->done); + + /* disable rx ints */ + mpc8xxx_spi_write_reg(®_base->mask, 0); + + return mpc8xxx_spi->count; +} + +static inline void fsl_espi_addr2cmd(unsigned int addr, u8 *cmd) +{ + if (cmd) { + cmd[1] = (u8)(addr >> 16); + cmd[2] = (u8)(addr >> 8); + cmd[3] = (u8)(addr >> 0); + } +} + +static inline unsigned int fsl_espi_cmd2addr(u8 *cmd) +{ + if (cmd) + return cmd[1] << 16 | cmd[2] << 8 | cmd[3] << 0; + + return 0; +} + +static void fsl_espi_do_trans(struct spi_message *m, + struct fsl_espi_transfer *tr) +{ + struct spi_device *spi = m->spi; + struct mpc8xxx_spi *mspi = spi_master_get_devdata(spi->master); + struct fsl_espi_transfer *espi_trans = tr; + struct spi_message message; + struct spi_transfer *t, *first, trans; + int status = 0; + + spi_message_init(&message); + memset(&trans, 0, sizeof(trans)); + + first = list_first_entry(&m->transfers, struct spi_transfer, + transfer_list); + list_for_each_entry(t, &m->transfers, transfer_list) { + if ((first->bits_per_word != t->bits_per_word) || + (first->speed_hz != t->speed_hz)) { + espi_trans->status = -EINVAL; + dev_err(mspi->dev, + "bits_per_word/speed_hz should be same for the same SPI transfer\n"); + return; + } + + trans.speed_hz = t->speed_hz; + trans.bits_per_word = t->bits_per_word; + trans.delay_usecs = max(first->delay_usecs, t->delay_usecs); + } + + trans.len = espi_trans->len; + trans.tx_buf = espi_trans->tx_buf; + trans.rx_buf = espi_trans->rx_buf; + spi_message_add_tail(&trans, &message); + + list_for_each_entry(t, &message.transfers, transfer_list) { + if (t->bits_per_word || t->speed_hz) { + status = -EINVAL; + + status = fsl_espi_setup_transfer(spi, t); + if (status < 0) + break; + } + + if (t->len) + status = fsl_espi_bufs(spi, t); + + if (status) { + status = -EMSGSIZE; + break; + } + + if (t->delay_usecs) + udelay(t->delay_usecs); + } + + espi_trans->status = status; + fsl_espi_setup_transfer(spi, NULL); +} + +static void fsl_espi_cmd_trans(struct spi_message *m, + struct fsl_espi_transfer *trans, u8 *rx_buff) +{ + struct spi_transfer *t; + u8 *local_buf; + int i = 0; + struct fsl_espi_transfer *espi_trans = trans; + + local_buf = kzalloc(SPCOM_TRANLEN_MAX, GFP_KERNEL); + if (!local_buf) { + espi_trans->status = -ENOMEM; + return; + } + + list_for_each_entry(t, &m->transfers, transfer_list) { + if (t->tx_buf) { + memcpy(local_buf + i, t->tx_buf, t->len); + i += t->len; + } + } + + espi_trans->tx_buf = local_buf; + espi_trans->rx_buf = local_buf; + fsl_espi_do_trans(m, espi_trans); + + espi_trans->actual_length = espi_trans->len; + kfree(local_buf); +} + +static void fsl_espi_rw_trans(struct spi_message *m, + struct fsl_espi_transfer *trans, u8 *rx_buff) +{ + struct fsl_espi_transfer *espi_trans = trans; + unsigned int total_len = espi_trans->len; + struct spi_transfer *t; + u8 *local_buf; + u8 *rx_buf = rx_buff; + unsigned int trans_len; + unsigned int addr; + unsigned int tx_only; + unsigned int rx_pos = 0; + unsigned int pos; + int i, loop; + + local_buf = kzalloc(SPCOM_TRANLEN_MAX, GFP_KERNEL); + if (!local_buf) { + espi_trans->status = -ENOMEM; + return; + } + + for (pos = 0, loop = 0; pos < total_len; pos += trans_len, loop++) { + trans_len = total_len - pos; + + i = 0; + tx_only = 0; + list_for_each_entry(t, &m->transfers, transfer_list) { + if (t->tx_buf) { + memcpy(local_buf + i, t->tx_buf, t->len); + i += t->len; + if (!t->rx_buf) + tx_only += t->len; + } + } + + /* Add additional TX bytes to compensate SPCOM_TRANLEN_MAX */ + if (loop > 0) + trans_len += tx_only; + + if (trans_len > SPCOM_TRANLEN_MAX) + trans_len = SPCOM_TRANLEN_MAX; + + /* Update device offset */ + if (pos > 0) { + addr = fsl_espi_cmd2addr(local_buf); + addr += rx_pos; + fsl_espi_addr2cmd(addr, local_buf); + } + + espi_trans->len = trans_len; + espi_trans->tx_buf = local_buf; + espi_trans->rx_buf = local_buf; + fsl_espi_do_trans(m, espi_trans); + + /* If there is at least one RX byte then copy it to rx_buf */ + if (tx_only < SPCOM_TRANLEN_MAX) + memcpy(rx_buf + rx_pos, espi_trans->rx_buf + tx_only, + trans_len - tx_only); + + rx_pos += trans_len - tx_only; + + if (loop > 0) + espi_trans->actual_length += espi_trans->len - tx_only; + else + espi_trans->actual_length += espi_trans->len; + } + + kfree(local_buf); +} + +static int fsl_espi_do_one_msg(struct spi_master *master, + struct spi_message *m) +{ + struct spi_transfer *t; + u8 *rx_buf = NULL; + unsigned int n_tx = 0; + unsigned int n_rx = 0; + unsigned int xfer_len = 0; + struct fsl_espi_transfer espi_trans; + + list_for_each_entry(t, &m->transfers, transfer_list) { + if (t->tx_buf) + n_tx += t->len; + if (t->rx_buf) { + n_rx += t->len; + rx_buf = t->rx_buf; + } + if ((t->tx_buf) || (t->rx_buf)) + xfer_len += t->len; + } + + espi_trans.n_tx = n_tx; + espi_trans.n_rx = n_rx; + espi_trans.len = xfer_len; + espi_trans.actual_length = 0; + espi_trans.status = 0; + + if (!rx_buf) + fsl_espi_cmd_trans(m, &espi_trans, NULL); + else + fsl_espi_rw_trans(m, &espi_trans, rx_buf); + + m->actual_length = espi_trans.actual_length; + m->status = espi_trans.status; + spi_finalize_current_message(master); + return 0; +} + +static int fsl_espi_setup(struct spi_device *spi) +{ + struct mpc8xxx_spi *mpc8xxx_spi; + struct fsl_espi_reg *reg_base; + int retval; + u32 hw_mode; + u32 loop_mode; + struct spi_mpc8xxx_cs *cs = spi_get_ctldata(spi); + + if (!spi->max_speed_hz) + return -EINVAL; + + if (!cs) { + cs = kzalloc(sizeof(*cs), GFP_KERNEL); + if (!cs) + return -ENOMEM; + spi_set_ctldata(spi, cs); + } + + mpc8xxx_spi = spi_master_get_devdata(spi->master); + reg_base = mpc8xxx_spi->reg_base; + + hw_mode = cs->hw_mode; /* Save original settings */ + cs->hw_mode = mpc8xxx_spi_read_reg( + ®_base->csmode[spi->chip_select]); + /* mask out bits we are going to set */ + cs->hw_mode &= ~(CSMODE_CP_BEGIN_EDGECLK | CSMODE_CI_INACTIVEHIGH + | CSMODE_REV); + + if (spi->mode & SPI_CPHA) + cs->hw_mode |= CSMODE_CP_BEGIN_EDGECLK; + if (spi->mode & SPI_CPOL) + cs->hw_mode |= CSMODE_CI_INACTIVEHIGH; + if (!(spi->mode & SPI_LSB_FIRST)) + cs->hw_mode |= CSMODE_REV; + + /* Handle the loop mode */ + loop_mode = mpc8xxx_spi_read_reg(®_base->mode); + loop_mode &= ~SPMODE_LOOP; + if (spi->mode & SPI_LOOP) + loop_mode |= SPMODE_LOOP; + mpc8xxx_spi_write_reg(®_base->mode, loop_mode); + + retval = fsl_espi_setup_transfer(spi, NULL); + if (retval < 0) { + cs->hw_mode = hw_mode; /* Restore settings */ + return retval; + } + return 0; +} + +static void fsl_espi_cleanup(struct spi_device *spi) +{ + struct spi_mpc8xxx_cs *cs = spi_get_ctldata(spi); + + kfree(cs); + spi_set_ctldata(spi, NULL); +} + +void fsl_espi_cpu_irq(struct mpc8xxx_spi *mspi, u32 events) +{ + struct fsl_espi_reg *reg_base = mspi->reg_base; + + /* We need handle RX first */ + if (events & SPIE_NE) { + u32 rx_data, tmp; + u8 rx_data_8; + + /* Spin until RX is done */ + while (SPIE_RXCNT(events) < min(4, mspi->len)) { + cpu_relax(); + events = mpc8xxx_spi_read_reg(®_base->event); + } + + if (mspi->len >= 4) { + rx_data = mpc8xxx_spi_read_reg(®_base->receive); + } else { + tmp = mspi->len; + rx_data = 0; + while (tmp--) { + rx_data_8 = in_8((u8 *)®_base->receive); + rx_data |= (rx_data_8 << (tmp * 8)); + } + + rx_data <<= (4 - mspi->len) * 8; + } + + mspi->len -= 4; + + if (mspi->rx) + mspi->get_rx(rx_data, mspi); + } + + if (!(events & SPIE_NF)) { + int ret; + + /* spin until TX is done */ + ret = spin_event_timeout(((events = mpc8xxx_spi_read_reg( + ®_base->event)) & SPIE_NF) == 0, 1000, 0); + if (!ret) { + dev_err(mspi->dev, "tired waiting for SPIE_NF\n"); + return; + } + } + + /* Clear the events */ + mpc8xxx_spi_write_reg(®_base->event, events); + + mspi->count -= 1; + if (mspi->count) { + u32 word = mspi->get_tx(mspi); + + mpc8xxx_spi_write_reg(®_base->transmit, word); + } else { + complete(&mspi->done); + } +} + +static irqreturn_t fsl_espi_irq(s32 irq, void *context_data) +{ + struct mpc8xxx_spi *mspi = context_data; + struct fsl_espi_reg *reg_base = mspi->reg_base; + irqreturn_t ret = IRQ_NONE; + u32 events; + + /* Get interrupt events(tx/rx) */ + events = mpc8xxx_spi_read_reg(®_base->event); + if (events) + ret = IRQ_HANDLED; + + dev_vdbg(mspi->dev, "%s: events %x\n", __func__, events); + + fsl_espi_cpu_irq(mspi, events); + + return ret; +} + +static void fsl_espi_remove(struct mpc8xxx_spi *mspi) +{ + iounmap(mspi->reg_base); +} + +static int fsl_espi_suspend(struct spi_master *master) +{ + struct mpc8xxx_spi *mpc8xxx_spi; + struct fsl_espi_reg *reg_base; + u32 regval; + + mpc8xxx_spi = spi_master_get_devdata(master); + reg_base = mpc8xxx_spi->reg_base; + + regval = mpc8xxx_spi_read_reg(®_base->mode); + regval &= ~SPMODE_ENABLE; + mpc8xxx_spi_write_reg(®_base->mode, regval); + + return 0; +} + +static int fsl_espi_resume(struct spi_master *master) +{ + struct mpc8xxx_spi *mpc8xxx_spi; + struct fsl_espi_reg *reg_base; + u32 regval; + + mpc8xxx_spi = spi_master_get_devdata(master); + reg_base = mpc8xxx_spi->reg_base; + + regval = mpc8xxx_spi_read_reg(®_base->mode); + regval |= SPMODE_ENABLE; + mpc8xxx_spi_write_reg(®_base->mode, regval); + + return 0; +} + +static struct spi_master * fsl_espi_probe(struct device *dev, + struct resource *mem, unsigned int irq) +{ + struct fsl_spi_platform_data *pdata = dev_get_platdata(dev); + struct spi_master *master; + struct mpc8xxx_spi *mpc8xxx_spi; + struct fsl_espi_reg *reg_base; + struct device_node *nc; + const __be32 *prop; + u32 regval, csmode; + int i, len, ret = 0; + + master = spi_alloc_master(dev, sizeof(struct mpc8xxx_spi)); + if (!master) { + ret = -ENOMEM; + goto err; + } + + dev_set_drvdata(dev, master); + + mpc8xxx_spi_probe(dev, mem, irq); + + master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 16); + master->setup = fsl_espi_setup; + master->cleanup = fsl_espi_cleanup; + master->transfer_one_message = fsl_espi_do_one_msg; + master->prepare_transfer_hardware = fsl_espi_resume; + master->unprepare_transfer_hardware = fsl_espi_suspend; + + mpc8xxx_spi = spi_master_get_devdata(master); + mpc8xxx_spi->spi_remove = fsl_espi_remove; + + mpc8xxx_spi->reg_base = ioremap(mem->start, resource_size(mem)); + if (!mpc8xxx_spi->reg_base) { + ret = -ENOMEM; + goto err_probe; + } + + reg_base = mpc8xxx_spi->reg_base; + + /* Register for SPI Interrupt */ + ret = request_irq(mpc8xxx_spi->irq, fsl_espi_irq, + 0, "fsl_espi", mpc8xxx_spi); + if (ret) + goto free_irq; + + if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE) { + mpc8xxx_spi->rx_shift = 16; + mpc8xxx_spi->tx_shift = 24; + } + + /* SPI controller initializations */ + mpc8xxx_spi_write_reg(®_base->mode, 0); + mpc8xxx_spi_write_reg(®_base->mask, 0); + mpc8xxx_spi_write_reg(®_base->command, 0); + mpc8xxx_spi_write_reg(®_base->event, 0xffffffff); + + /* Init eSPI CS mode register */ + for_each_available_child_of_node(master->dev.of_node, nc) { + /* get chip select */ + prop = of_get_property(nc, "reg", &len); + if (!prop || len < sizeof(*prop)) + continue; + i = be32_to_cpup(prop); + if (i < 0 || i >= pdata->max_chipselect) + continue; + + csmode = CSMODE_INIT_VAL; + /* check if CSBEF is set in device tree */ + prop = of_get_property(nc, "fsl,csbef", &len); + if (prop && len >= sizeof(*prop)) { + csmode &= ~(CSMODE_BEF(0xf)); + csmode |= CSMODE_BEF(be32_to_cpup(prop)); + } + /* check if CSAFT is set in device tree */ + prop = of_get_property(nc, "fsl,csaft", &len); + if (prop && len >= sizeof(*prop)) { + csmode &= ~(CSMODE_AFT(0xf)); + csmode |= CSMODE_AFT(be32_to_cpup(prop)); + } + mpc8xxx_spi_write_reg(®_base->csmode[i], csmode); + + dev_info(dev, "cs=%d, init_csmode=0x%x\n", i, csmode); + } + + /* Enable SPI interface */ + regval = pdata->initial_spmode | SPMODE_INIT_VAL | SPMODE_ENABLE; + + mpc8xxx_spi_write_reg(®_base->mode, regval); + + ret = spi_register_master(master); + if (ret < 0) + goto unreg_master; + + dev_info(dev, "at 0x%p (irq = %d)\n", reg_base, mpc8xxx_spi->irq); + + return master; + +unreg_master: + free_irq(mpc8xxx_spi->irq, mpc8xxx_spi); +free_irq: + iounmap(mpc8xxx_spi->reg_base); +err_probe: + spi_master_put(master); +err: + return ERR_PTR(ret); +} + +static int of_fsl_espi_get_chipselects(struct device *dev) +{ + struct device_node *np = dev->of_node; + struct fsl_spi_platform_data *pdata = dev_get_platdata(dev); + const u32 *prop; + int len; + + prop = of_get_property(np, "fsl,espi-num-chipselects", &len); + if (!prop || len < sizeof(*prop)) { + dev_err(dev, "No 'fsl,espi-num-chipselects' property\n"); + return -EINVAL; + } + + pdata->max_chipselect = *prop; + pdata->cs_control = NULL; + + return 0; +} + +static int of_fsl_espi_probe(struct platform_device *ofdev) +{ + struct device *dev = &ofdev->dev; + struct device_node *np = ofdev->dev.of_node; + struct spi_master *master; + struct resource mem; + unsigned int irq; + int ret = -ENOMEM; + + ret = of_mpc8xxx_spi_probe(ofdev); + if (ret) + return ret; + + ret = of_fsl_espi_get_chipselects(dev); + if (ret) + goto err; + + ret = of_address_to_resource(np, 0, &mem); + if (ret) + goto err; + + irq = irq_of_parse_and_map(np, 0); + if (!irq) { + ret = -EINVAL; + goto err; + } + + master = fsl_espi_probe(dev, &mem, irq); + if (IS_ERR(master)) { + ret = PTR_ERR(master); + goto err; + } + + return 0; + +err: + return ret; +} + +static int of_fsl_espi_remove(struct platform_device *dev) +{ + return mpc8xxx_spi_remove(&dev->dev); +} + +#ifdef CONFIG_PM_SLEEP +static int of_fsl_espi_suspend(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + int ret; + + ret = spi_master_suspend(master); + if (ret) { + dev_warn(dev, "cannot suspend master\n"); + return ret; + } + + return fsl_espi_suspend(master); +} + +static int of_fsl_espi_resume(struct device *dev) +{ + struct fsl_spi_platform_data *pdata = dev_get_platdata(dev); + struct spi_master *master = dev_get_drvdata(dev); + struct mpc8xxx_spi *mpc8xxx_spi; + struct fsl_espi_reg *reg_base; + u32 regval; + int i; + + mpc8xxx_spi = spi_master_get_devdata(master); + reg_base = mpc8xxx_spi->reg_base; + + /* SPI controller initializations */ + mpc8xxx_spi_write_reg(®_base->mode, 0); + mpc8xxx_spi_write_reg(®_base->mask, 0); + mpc8xxx_spi_write_reg(®_base->command, 0); + mpc8xxx_spi_write_reg(®_base->event, 0xffffffff); + + /* Init eSPI CS mode register */ + for (i = 0; i < pdata->max_chipselect; i++) + mpc8xxx_spi_write_reg(®_base->csmode[i], CSMODE_INIT_VAL); + + /* Enable SPI interface */ + regval = pdata->initial_spmode | SPMODE_INIT_VAL | SPMODE_ENABLE; + + mpc8xxx_spi_write_reg(®_base->mode, regval); + + return spi_master_resume(master); +} +#endif /* CONFIG_PM_SLEEP */ + +static const struct dev_pm_ops espi_pm = { + SET_SYSTEM_SLEEP_PM_OPS(of_fsl_espi_suspend, of_fsl_espi_resume) +}; + +static const struct of_device_id of_fsl_espi_match[] = { + { .compatible = "fsl,mpc8536-espi" }, + {} +}; +MODULE_DEVICE_TABLE(of, of_fsl_espi_match); + +static struct platform_driver fsl_espi_driver = { + .driver = { + .name = "fsl_espi", + .of_match_table = of_fsl_espi_match, + .pm = &espi_pm, + }, + .probe = of_fsl_espi_probe, + .remove = of_fsl_espi_remove, +}; +module_platform_driver(fsl_espi_driver); + +MODULE_AUTHOR("Mingkai Hu"); +MODULE_DESCRIPTION("Enhanced Freescale SPI Driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/spi/spi-fsl-lib.c b/drivers/spi/spi-fsl-lib.c new file mode 100644 index 000000000..cb35d2f0d --- /dev/null +++ b/drivers/spi/spi-fsl-lib.c @@ -0,0 +1,183 @@ +/* + * Freescale SPI/eSPI controller driver library. + * + * Maintainer: Kumar Gala + * + * Copyright (C) 2006 Polycom, Inc. + * + * CPM SPI and QE buffer descriptors mode support: + * Copyright (c) 2009 MontaVista Software, Inc. + * Author: Anton Vorontsov <avorontsov@ru.mvista.com> + * + * Copyright 2010 Freescale Semiconductor, Inc. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + */ +#include <linux/dma-mapping.h> +#include <linux/fsl_devices.h> +#include <linux/interrupt.h> +#include <linux/kernel.h> +#include <linux/mm.h> +#include <linux/module.h> +#include <linux/of_platform.h> +#include <linux/spi/spi.h> +#ifdef CONFIG_FSL_SOC +#include <sysdev/fsl_soc.h> +#endif + +#include "spi-fsl-lib.h" + +#define MPC8XXX_SPI_RX_BUF(type) \ +void mpc8xxx_spi_rx_buf_##type(u32 data, struct mpc8xxx_spi *mpc8xxx_spi) \ +{ \ + type *rx = mpc8xxx_spi->rx; \ + *rx++ = (type)(data >> mpc8xxx_spi->rx_shift); \ + mpc8xxx_spi->rx = rx; \ +} \ +EXPORT_SYMBOL_GPL(mpc8xxx_spi_rx_buf_##type); + +#define MPC8XXX_SPI_TX_BUF(type) \ +u32 mpc8xxx_spi_tx_buf_##type(struct mpc8xxx_spi *mpc8xxx_spi) \ +{ \ + u32 data; \ + const type *tx = mpc8xxx_spi->tx; \ + if (!tx) \ + return 0; \ + data = *tx++ << mpc8xxx_spi->tx_shift; \ + mpc8xxx_spi->tx = tx; \ + return data; \ +} \ +EXPORT_SYMBOL_GPL(mpc8xxx_spi_tx_buf_##type); + +MPC8XXX_SPI_RX_BUF(u8) +MPC8XXX_SPI_RX_BUF(u16) +MPC8XXX_SPI_RX_BUF(u32) +MPC8XXX_SPI_TX_BUF(u8) +MPC8XXX_SPI_TX_BUF(u16) +MPC8XXX_SPI_TX_BUF(u32) + +struct mpc8xxx_spi_probe_info *to_of_pinfo(struct fsl_spi_platform_data *pdata) +{ + return container_of(pdata, struct mpc8xxx_spi_probe_info, pdata); +} +EXPORT_SYMBOL_GPL(to_of_pinfo); + +const char *mpc8xxx_spi_strmode(unsigned int flags) +{ + if (flags & SPI_QE_CPU_MODE) { + return "QE CPU"; + } else if (flags & SPI_CPM_MODE) { + if (flags & SPI_QE) + return "QE"; + else if (flags & SPI_CPM2) + return "CPM2"; + else + return "CPM1"; + } + return "CPU"; +} +EXPORT_SYMBOL_GPL(mpc8xxx_spi_strmode); + +void mpc8xxx_spi_probe(struct device *dev, struct resource *mem, + unsigned int irq) +{ + struct fsl_spi_platform_data *pdata = dev_get_platdata(dev); + struct spi_master *master; + struct mpc8xxx_spi *mpc8xxx_spi; + + master = dev_get_drvdata(dev); + + /* the spi->mode bits understood by this driver: */ + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH + | SPI_LSB_FIRST | SPI_LOOP; + + master->dev.of_node = dev->of_node; + + mpc8xxx_spi = spi_master_get_devdata(master); + mpc8xxx_spi->dev = dev; + mpc8xxx_spi->get_rx = mpc8xxx_spi_rx_buf_u8; + mpc8xxx_spi->get_tx = mpc8xxx_spi_tx_buf_u8; + mpc8xxx_spi->flags = pdata->flags; + mpc8xxx_spi->spibrg = pdata->sysclk; + mpc8xxx_spi->irq = irq; + + mpc8xxx_spi->rx_shift = 0; + mpc8xxx_spi->tx_shift = 0; + + master->bus_num = pdata->bus_num; + master->num_chipselect = pdata->max_chipselect; + + init_completion(&mpc8xxx_spi->done); +} +EXPORT_SYMBOL_GPL(mpc8xxx_spi_probe); + +int mpc8xxx_spi_remove(struct device *dev) +{ + struct mpc8xxx_spi *mpc8xxx_spi; + struct spi_master *master; + + master = dev_get_drvdata(dev); + mpc8xxx_spi = spi_master_get_devdata(master); + + spi_unregister_master(master); + + free_irq(mpc8xxx_spi->irq, mpc8xxx_spi); + + if (mpc8xxx_spi->spi_remove) + mpc8xxx_spi->spi_remove(mpc8xxx_spi); + + return 0; +} +EXPORT_SYMBOL_GPL(mpc8xxx_spi_remove); + +int of_mpc8xxx_spi_probe(struct platform_device *ofdev) +{ + struct device *dev = &ofdev->dev; + struct device_node *np = ofdev->dev.of_node; + struct mpc8xxx_spi_probe_info *pinfo; + struct fsl_spi_platform_data *pdata; + const void *prop; + int ret = -ENOMEM; + + pinfo = devm_kzalloc(&ofdev->dev, sizeof(*pinfo), GFP_KERNEL); + if (!pinfo) + return ret; + + pdata = &pinfo->pdata; + dev->platform_data = pdata; + + /* Allocate bus num dynamically. */ + pdata->bus_num = -1; + +#ifdef CONFIG_FSL_SOC + /* SPI controller is either clocked from QE or SoC clock. */ + pdata->sysclk = get_brgfreq(); + if (pdata->sysclk == -1) { + pdata->sysclk = fsl_get_sys_freq(); + if (pdata->sysclk == -1) + return -ENODEV; + } +#else + ret = of_property_read_u32(np, "clock-frequency", &pdata->sysclk); + if (ret) + return ret; +#endif + + prop = of_get_property(np, "mode", NULL); + if (prop && !strcmp(prop, "cpu-qe")) + pdata->flags = SPI_QE_CPU_MODE; + else if (prop && !strcmp(prop, "qe")) + pdata->flags = SPI_CPM_MODE | SPI_QE; + else if (of_device_is_compatible(np, "fsl,cpm2-spi")) + pdata->flags = SPI_CPM_MODE | SPI_CPM2; + else if (of_device_is_compatible(np, "fsl,cpm1-spi")) + pdata->flags = SPI_CPM_MODE | SPI_CPM1; + + return 0; +} +EXPORT_SYMBOL_GPL(of_mpc8xxx_spi_probe); + +MODULE_LICENSE("GPL"); diff --git a/drivers/spi/spi-fsl-lib.h b/drivers/spi/spi-fsl-lib.h new file mode 100644 index 000000000..1326a392a --- /dev/null +++ b/drivers/spi/spi-fsl-lib.h @@ -0,0 +1,125 @@ +/* + * Freescale SPI/eSPI controller driver library. + * + * Maintainer: Kumar Gala + * + * Copyright 2010 Freescale Semiconductor, Inc. + * Copyright (C) 2006 Polycom, Inc. + * + * CPM SPI and QE buffer descriptors mode support: + * Copyright (c) 2009 MontaVista Software, Inc. + * Author: Anton Vorontsov <avorontsov@ru.mvista.com> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + */ +#ifndef __SPI_FSL_LIB_H__ +#define __SPI_FSL_LIB_H__ + +#include <asm/io.h> + +/* SPI/eSPI Controller driver's private data. */ +struct mpc8xxx_spi { + struct device *dev; + void *reg_base; + + /* rx & tx bufs from the spi_transfer */ + const void *tx; + void *rx; +#if IS_ENABLED(CONFIG_SPI_FSL_ESPI) + int len; +#endif + + int subblock; + struct spi_pram __iomem *pram; +#ifdef CONFIG_FSL_SOC + struct cpm_buf_desc __iomem *tx_bd; + struct cpm_buf_desc __iomem *rx_bd; +#endif + + struct spi_transfer *xfer_in_progress; + + /* dma addresses for CPM transfers */ + dma_addr_t tx_dma; + dma_addr_t rx_dma; + bool map_tx_dma; + bool map_rx_dma; + + dma_addr_t dma_dummy_tx; + dma_addr_t dma_dummy_rx; + + /* functions to deal with different sized buffers */ + void (*get_rx) (u32 rx_data, struct mpc8xxx_spi *); + u32(*get_tx) (struct mpc8xxx_spi *); + + /* hooks for different controller driver */ + void (*spi_remove) (struct mpc8xxx_spi *mspi); + + unsigned int count; + unsigned int irq; + + unsigned nsecs; /* (clock cycle time)/2 */ + + u32 spibrg; /* SPIBRG input clock */ + u32 rx_shift; /* RX data reg shift when in qe mode */ + u32 tx_shift; /* TX data reg shift when in qe mode */ + + unsigned int flags; + +#if IS_ENABLED(CONFIG_SPI_FSL_SPI) + int type; + int native_chipselects; + u8 max_bits_per_word; + + void (*set_shifts)(u32 *rx_shift, u32 *tx_shift, + int bits_per_word, int msb_first); +#endif + + struct completion done; +}; + +struct spi_mpc8xxx_cs { + /* functions to deal with different sized buffers */ + void (*get_rx) (u32 rx_data, struct mpc8xxx_spi *); + u32 (*get_tx) (struct mpc8xxx_spi *); + u32 rx_shift; /* RX data reg shift when in qe mode */ + u32 tx_shift; /* TX data reg shift when in qe mode */ + u32 hw_mode; /* Holds HW mode register settings */ +}; + +static inline void mpc8xxx_spi_write_reg(__be32 __iomem *reg, u32 val) +{ + iowrite32be(val, reg); +} + +static inline u32 mpc8xxx_spi_read_reg(__be32 __iomem *reg) +{ + return ioread32be(reg); +} + +struct mpc8xxx_spi_probe_info { + struct fsl_spi_platform_data pdata; + int *gpios; + bool *alow_flags; +}; + +extern u32 mpc8xxx_spi_tx_buf_u8(struct mpc8xxx_spi *mpc8xxx_spi); +extern u32 mpc8xxx_spi_tx_buf_u16(struct mpc8xxx_spi *mpc8xxx_spi); +extern u32 mpc8xxx_spi_tx_buf_u32(struct mpc8xxx_spi *mpc8xxx_spi); +extern void mpc8xxx_spi_rx_buf_u8(u32 data, struct mpc8xxx_spi *mpc8xxx_spi); +extern void mpc8xxx_spi_rx_buf_u16(u32 data, struct mpc8xxx_spi *mpc8xxx_spi); +extern void mpc8xxx_spi_rx_buf_u32(u32 data, struct mpc8xxx_spi *mpc8xxx_spi); + +extern struct mpc8xxx_spi_probe_info *to_of_pinfo( + struct fsl_spi_platform_data *pdata); +extern int mpc8xxx_spi_bufs(struct mpc8xxx_spi *mspi, + struct spi_transfer *t, unsigned int len); +extern const char *mpc8xxx_spi_strmode(unsigned int flags); +extern void mpc8xxx_spi_probe(struct device *dev, struct resource *mem, + unsigned int irq); +extern int mpc8xxx_spi_remove(struct device *dev); +extern int of_mpc8xxx_spi_probe(struct platform_device *ofdev); + +#endif /* __SPI_FSL_LIB_H__ */ diff --git a/drivers/spi/spi-fsl-spi.c b/drivers/spi/spi-fsl-spi.c new file mode 100644 index 000000000..60c590790 --- /dev/null +++ b/drivers/spi/spi-fsl-spi.c @@ -0,0 +1,965 @@ +/* + * Freescale SPI controller driver. + * + * Maintainer: Kumar Gala + * + * Copyright (C) 2006 Polycom, Inc. + * Copyright 2010 Freescale Semiconductor, Inc. + * + * CPM SPI and QE buffer descriptors mode support: + * Copyright (c) 2009 MontaVista Software, Inc. + * Author: Anton Vorontsov <avorontsov@ru.mvista.com> + * + * GRLIB support: + * Copyright (c) 2012 Aeroflex Gaisler AB. + * Author: Andreas Larsson <andreas@gaisler.com> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + */ +#include <linux/delay.h> +#include <linux/dma-mapping.h> +#include <linux/fsl_devices.h> +#include <linux/gpio.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/kernel.h> +#include <linux/mm.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/of_gpio.h> +#include <linux/of_platform.h> +#include <linux/platform_device.h> +#include <linux/spi/spi.h> +#include <linux/spi/spi_bitbang.h> +#include <linux/types.h> + +#include "spi-fsl-lib.h" +#include "spi-fsl-cpm.h" +#include "spi-fsl-spi.h" + +#define TYPE_FSL 0 +#define TYPE_GRLIB 1 + +struct fsl_spi_match_data { + int type; +}; + +static struct fsl_spi_match_data of_fsl_spi_fsl_config = { + .type = TYPE_FSL, +}; + +static struct fsl_spi_match_data of_fsl_spi_grlib_config = { + .type = TYPE_GRLIB, +}; + +static const struct of_device_id of_fsl_spi_match[] = { + { + .compatible = "fsl,spi", + .data = &of_fsl_spi_fsl_config, + }, + { + .compatible = "aeroflexgaisler,spictrl", + .data = &of_fsl_spi_grlib_config, + }, + {} +}; +MODULE_DEVICE_TABLE(of, of_fsl_spi_match); + +static int fsl_spi_get_type(struct device *dev) +{ + const struct of_device_id *match; + + if (dev->of_node) { + match = of_match_node(of_fsl_spi_match, dev->of_node); + if (match && match->data) + return ((struct fsl_spi_match_data *)match->data)->type; + } + return TYPE_FSL; +} + +static void fsl_spi_change_mode(struct spi_device *spi) +{ + struct mpc8xxx_spi *mspi = spi_master_get_devdata(spi->master); + struct spi_mpc8xxx_cs *cs = spi->controller_state; + struct fsl_spi_reg *reg_base = mspi->reg_base; + __be32 __iomem *mode = ®_base->mode; + unsigned long flags; + + if (cs->hw_mode == mpc8xxx_spi_read_reg(mode)) + return; + + /* Turn off IRQs locally to minimize time that SPI is disabled. */ + local_irq_save(flags); + + /* Turn off SPI unit prior changing mode */ + mpc8xxx_spi_write_reg(mode, cs->hw_mode & ~SPMODE_ENABLE); + + /* When in CPM mode, we need to reinit tx and rx. */ + if (mspi->flags & SPI_CPM_MODE) { + fsl_spi_cpm_reinit_txrx(mspi); + } + mpc8xxx_spi_write_reg(mode, cs->hw_mode); + local_irq_restore(flags); +} + +static void fsl_spi_chipselect(struct spi_device *spi, int value) +{ + struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master); + struct fsl_spi_platform_data *pdata; + bool pol = spi->mode & SPI_CS_HIGH; + struct spi_mpc8xxx_cs *cs = spi->controller_state; + + pdata = spi->dev.parent->parent->platform_data; + + if (value == BITBANG_CS_INACTIVE) { + if (pdata->cs_control) + pdata->cs_control(spi, !pol); + } + + if (value == BITBANG_CS_ACTIVE) { + mpc8xxx_spi->rx_shift = cs->rx_shift; + mpc8xxx_spi->tx_shift = cs->tx_shift; + mpc8xxx_spi->get_rx = cs->get_rx; + mpc8xxx_spi->get_tx = cs->get_tx; + + fsl_spi_change_mode(spi); + + if (pdata->cs_control) + pdata->cs_control(spi, pol); + } +} + +static void fsl_spi_qe_cpu_set_shifts(u32 *rx_shift, u32 *tx_shift, + int bits_per_word, int msb_first) +{ + *rx_shift = 0; + *tx_shift = 0; + if (msb_first) { + if (bits_per_word <= 8) { + *rx_shift = 16; + *tx_shift = 24; + } else if (bits_per_word <= 16) { + *rx_shift = 16; + *tx_shift = 16; + } + } else { + if (bits_per_word <= 8) + *rx_shift = 8; + } +} + +static void fsl_spi_grlib_set_shifts(u32 *rx_shift, u32 *tx_shift, + int bits_per_word, int msb_first) +{ + *rx_shift = 0; + *tx_shift = 0; + if (bits_per_word <= 16) { + if (msb_first) { + *rx_shift = 16; /* LSB in bit 16 */ + *tx_shift = 32 - bits_per_word; /* MSB in bit 31 */ + } else { + *rx_shift = 16 - bits_per_word; /* MSB in bit 15 */ + } + } +} + +static int mspi_apply_cpu_mode_quirks(struct spi_mpc8xxx_cs *cs, + struct spi_device *spi, + struct mpc8xxx_spi *mpc8xxx_spi, + int bits_per_word) +{ + cs->rx_shift = 0; + cs->tx_shift = 0; + if (bits_per_word <= 8) { + cs->get_rx = mpc8xxx_spi_rx_buf_u8; + cs->get_tx = mpc8xxx_spi_tx_buf_u8; + } else if (bits_per_word <= 16) { + cs->get_rx = mpc8xxx_spi_rx_buf_u16; + cs->get_tx = mpc8xxx_spi_tx_buf_u16; + } else if (bits_per_word <= 32) { + cs->get_rx = mpc8xxx_spi_rx_buf_u32; + cs->get_tx = mpc8xxx_spi_tx_buf_u32; + } else + return -EINVAL; + + if (mpc8xxx_spi->set_shifts) + mpc8xxx_spi->set_shifts(&cs->rx_shift, &cs->tx_shift, + bits_per_word, + !(spi->mode & SPI_LSB_FIRST)); + + mpc8xxx_spi->rx_shift = cs->rx_shift; + mpc8xxx_spi->tx_shift = cs->tx_shift; + mpc8xxx_spi->get_rx = cs->get_rx; + mpc8xxx_spi->get_tx = cs->get_tx; + + return bits_per_word; +} + +static int mspi_apply_qe_mode_quirks(struct spi_mpc8xxx_cs *cs, + struct spi_device *spi, + int bits_per_word) +{ + /* QE uses Little Endian for words > 8 + * so transform all words > 8 into 8 bits + * Unfortnatly that doesn't work for LSB so + * reject these for now */ + /* Note: 32 bits word, LSB works iff + * tfcr/rfcr is set to CPMFCR_GBL */ + if (spi->mode & SPI_LSB_FIRST && + bits_per_word > 8) + return -EINVAL; + if (bits_per_word > 8) + return 8; /* pretend its 8 bits */ + return bits_per_word; +} + +static int fsl_spi_setup_transfer(struct spi_device *spi, + struct spi_transfer *t) +{ + struct mpc8xxx_spi *mpc8xxx_spi; + int bits_per_word = 0; + u8 pm; + u32 hz = 0; + struct spi_mpc8xxx_cs *cs = spi->controller_state; + + mpc8xxx_spi = spi_master_get_devdata(spi->master); + + if (t) { + bits_per_word = t->bits_per_word; + hz = t->speed_hz; + } + + /* spi_transfer level calls that work per-word */ + if (!bits_per_word) + bits_per_word = spi->bits_per_word; + + if (!hz) + hz = spi->max_speed_hz; + + if (!(mpc8xxx_spi->flags & SPI_CPM_MODE)) + bits_per_word = mspi_apply_cpu_mode_quirks(cs, spi, + mpc8xxx_spi, + bits_per_word); + else if (mpc8xxx_spi->flags & SPI_QE) + bits_per_word = mspi_apply_qe_mode_quirks(cs, spi, + bits_per_word); + + if (bits_per_word < 0) + return bits_per_word; + + if (bits_per_word == 32) + bits_per_word = 0; + else + bits_per_word = bits_per_word - 1; + + /* mask out bits we are going to set */ + cs->hw_mode &= ~(SPMODE_LEN(0xF) | SPMODE_DIV16 + | SPMODE_PM(0xF)); + + cs->hw_mode |= SPMODE_LEN(bits_per_word); + + if ((mpc8xxx_spi->spibrg / hz) > 64) { + cs->hw_mode |= SPMODE_DIV16; + pm = (mpc8xxx_spi->spibrg - 1) / (hz * 64) + 1; + + WARN_ONCE(pm > 16, "%s: Requested speed is too low: %d Hz. " + "Will use %d Hz instead.\n", dev_name(&spi->dev), + hz, mpc8xxx_spi->spibrg / 1024); + if (pm > 16) + pm = 16; + } else { + pm = (mpc8xxx_spi->spibrg - 1) / (hz * 4) + 1; + } + if (pm) + pm--; + + cs->hw_mode |= SPMODE_PM(pm); + + fsl_spi_change_mode(spi); + return 0; +} + +static int fsl_spi_cpu_bufs(struct mpc8xxx_spi *mspi, + struct spi_transfer *t, unsigned int len) +{ + u32 word; + struct fsl_spi_reg *reg_base = mspi->reg_base; + + mspi->count = len; + + /* enable rx ints */ + mpc8xxx_spi_write_reg(®_base->mask, SPIM_NE); + + /* transmit word */ + word = mspi->get_tx(mspi); + mpc8xxx_spi_write_reg(®_base->transmit, word); + + return 0; +} + +static int fsl_spi_bufs(struct spi_device *spi, struct spi_transfer *t, + bool is_dma_mapped) +{ + struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master); + struct fsl_spi_reg *reg_base; + unsigned int len = t->len; + u8 bits_per_word; + int ret; + + reg_base = mpc8xxx_spi->reg_base; + bits_per_word = spi->bits_per_word; + if (t->bits_per_word) + bits_per_word = t->bits_per_word; + + if (bits_per_word > 8) { + /* invalid length? */ + if (len & 1) + return -EINVAL; + len /= 2; + } + if (bits_per_word > 16) { + /* invalid length? */ + if (len & 1) + return -EINVAL; + len /= 2; + } + + mpc8xxx_spi->tx = t->tx_buf; + mpc8xxx_spi->rx = t->rx_buf; + + reinit_completion(&mpc8xxx_spi->done); + + if (mpc8xxx_spi->flags & SPI_CPM_MODE) + ret = fsl_spi_cpm_bufs(mpc8xxx_spi, t, is_dma_mapped); + else + ret = fsl_spi_cpu_bufs(mpc8xxx_spi, t, len); + if (ret) + return ret; + + wait_for_completion(&mpc8xxx_spi->done); + + /* disable rx ints */ + mpc8xxx_spi_write_reg(®_base->mask, 0); + + if (mpc8xxx_spi->flags & SPI_CPM_MODE) + fsl_spi_cpm_bufs_complete(mpc8xxx_spi); + + return mpc8xxx_spi->count; +} + +static int fsl_spi_do_one_msg(struct spi_master *master, + struct spi_message *m) +{ + struct spi_device *spi = m->spi; + struct spi_transfer *t, *first; + unsigned int cs_change; + const int nsecs = 50; + int status; + + /* Don't allow changes if CS is active */ + first = list_first_entry(&m->transfers, struct spi_transfer, + transfer_list); + list_for_each_entry(t, &m->transfers, transfer_list) { + if ((first->bits_per_word != t->bits_per_word) || + (first->speed_hz != t->speed_hz)) { + dev_err(&spi->dev, + "bits_per_word/speed_hz should be same for the same SPI transfer\n"); + return -EINVAL; + } + } + + cs_change = 1; + status = -EINVAL; + list_for_each_entry(t, &m->transfers, transfer_list) { + if (t->bits_per_word || t->speed_hz) { + if (cs_change) + status = fsl_spi_setup_transfer(spi, t); + if (status < 0) + break; + } + + if (cs_change) { + fsl_spi_chipselect(spi, BITBANG_CS_ACTIVE); + ndelay(nsecs); + } + cs_change = t->cs_change; + if (t->len) + status = fsl_spi_bufs(spi, t, m->is_dma_mapped); + if (status) { + status = -EMSGSIZE; + break; + } + m->actual_length += t->len; + + if (t->delay_usecs) + udelay(t->delay_usecs); + + if (cs_change) { + ndelay(nsecs); + fsl_spi_chipselect(spi, BITBANG_CS_INACTIVE); + ndelay(nsecs); + } + } + + m->status = status; + spi_finalize_current_message(master); + + if (status || !cs_change) { + ndelay(nsecs); + fsl_spi_chipselect(spi, BITBANG_CS_INACTIVE); + } + + fsl_spi_setup_transfer(spi, NULL); + return 0; +} + +static int fsl_spi_setup(struct spi_device *spi) +{ + struct mpc8xxx_spi *mpc8xxx_spi; + struct fsl_spi_reg *reg_base; + int retval; + u32 hw_mode; + struct spi_mpc8xxx_cs *cs = spi_get_ctldata(spi); + + if (!spi->max_speed_hz) + return -EINVAL; + + if (!cs) { + cs = kzalloc(sizeof(*cs), GFP_KERNEL); + if (!cs) + return -ENOMEM; + spi_set_ctldata(spi, cs); + } + mpc8xxx_spi = spi_master_get_devdata(spi->master); + + reg_base = mpc8xxx_spi->reg_base; + + hw_mode = cs->hw_mode; /* Save original settings */ + cs->hw_mode = mpc8xxx_spi_read_reg(®_base->mode); + /* mask out bits we are going to set */ + cs->hw_mode &= ~(SPMODE_CP_BEGIN_EDGECLK | SPMODE_CI_INACTIVEHIGH + | SPMODE_REV | SPMODE_LOOP); + + if (spi->mode & SPI_CPHA) + cs->hw_mode |= SPMODE_CP_BEGIN_EDGECLK; + if (spi->mode & SPI_CPOL) + cs->hw_mode |= SPMODE_CI_INACTIVEHIGH; + if (!(spi->mode & SPI_LSB_FIRST)) + cs->hw_mode |= SPMODE_REV; + if (spi->mode & SPI_LOOP) + cs->hw_mode |= SPMODE_LOOP; + + retval = fsl_spi_setup_transfer(spi, NULL); + if (retval < 0) { + cs->hw_mode = hw_mode; /* Restore settings */ + return retval; + } + + if (mpc8xxx_spi->type == TYPE_GRLIB) { + if (gpio_is_valid(spi->cs_gpio)) { + int desel; + + retval = gpio_request(spi->cs_gpio, + dev_name(&spi->dev)); + if (retval) + return retval; + + desel = !(spi->mode & SPI_CS_HIGH); + retval = gpio_direction_output(spi->cs_gpio, desel); + if (retval) { + gpio_free(spi->cs_gpio); + return retval; + } + } else if (spi->cs_gpio != -ENOENT) { + if (spi->cs_gpio < 0) + return spi->cs_gpio; + return -EINVAL; + } + /* When spi->cs_gpio == -ENOENT, a hole in the phandle list + * indicates to use native chipselect if present, or allow for + * an always selected chip + */ + } + + /* Initialize chipselect - might be active for SPI_CS_HIGH mode */ + fsl_spi_chipselect(spi, BITBANG_CS_INACTIVE); + + return 0; +} + +static void fsl_spi_cleanup(struct spi_device *spi) +{ + struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master); + struct spi_mpc8xxx_cs *cs = spi_get_ctldata(spi); + + if (mpc8xxx_spi->type == TYPE_GRLIB && gpio_is_valid(spi->cs_gpio)) + gpio_free(spi->cs_gpio); + + kfree(cs); + spi_set_ctldata(spi, NULL); +} + +static void fsl_spi_cpu_irq(struct mpc8xxx_spi *mspi, u32 events) +{ + struct fsl_spi_reg *reg_base = mspi->reg_base; + + /* We need handle RX first */ + if (events & SPIE_NE) { + u32 rx_data = mpc8xxx_spi_read_reg(®_base->receive); + + if (mspi->rx) + mspi->get_rx(rx_data, mspi); + } + + if ((events & SPIE_NF) == 0) + /* spin until TX is done */ + while (((events = + mpc8xxx_spi_read_reg(®_base->event)) & + SPIE_NF) == 0) + cpu_relax(); + + /* Clear the events */ + mpc8xxx_spi_write_reg(®_base->event, events); + + mspi->count -= 1; + if (mspi->count) { + u32 word = mspi->get_tx(mspi); + + mpc8xxx_spi_write_reg(®_base->transmit, word); + } else { + complete(&mspi->done); + } +} + +static irqreturn_t fsl_spi_irq(s32 irq, void *context_data) +{ + struct mpc8xxx_spi *mspi = context_data; + irqreturn_t ret = IRQ_NONE; + u32 events; + struct fsl_spi_reg *reg_base = mspi->reg_base; + + /* Get interrupt events(tx/rx) */ + events = mpc8xxx_spi_read_reg(®_base->event); + if (events) + ret = IRQ_HANDLED; + + dev_dbg(mspi->dev, "%s: events %x\n", __func__, events); + + if (mspi->flags & SPI_CPM_MODE) + fsl_spi_cpm_irq(mspi, events); + else + fsl_spi_cpu_irq(mspi, events); + + return ret; +} + +static void fsl_spi_remove(struct mpc8xxx_spi *mspi) +{ + iounmap(mspi->reg_base); + fsl_spi_cpm_free(mspi); +} + +static void fsl_spi_grlib_cs_control(struct spi_device *spi, bool on) +{ + struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master); + struct fsl_spi_reg *reg_base = mpc8xxx_spi->reg_base; + u32 slvsel; + u16 cs = spi->chip_select; + + if (gpio_is_valid(spi->cs_gpio)) { + gpio_set_value(spi->cs_gpio, on); + } else if (cs < mpc8xxx_spi->native_chipselects) { + slvsel = mpc8xxx_spi_read_reg(®_base->slvsel); + slvsel = on ? (slvsel | (1 << cs)) : (slvsel & ~(1 << cs)); + mpc8xxx_spi_write_reg(®_base->slvsel, slvsel); + } +} + +static void fsl_spi_grlib_probe(struct device *dev) +{ + struct fsl_spi_platform_data *pdata = dev_get_platdata(dev); + struct spi_master *master = dev_get_drvdata(dev); + struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(master); + struct fsl_spi_reg *reg_base = mpc8xxx_spi->reg_base; + int mbits; + u32 capabilities; + + capabilities = mpc8xxx_spi_read_reg(®_base->cap); + + mpc8xxx_spi->set_shifts = fsl_spi_grlib_set_shifts; + mbits = SPCAP_MAXWLEN(capabilities); + if (mbits) + mpc8xxx_spi->max_bits_per_word = mbits + 1; + + mpc8xxx_spi->native_chipselects = 0; + if (SPCAP_SSEN(capabilities)) { + mpc8xxx_spi->native_chipselects = SPCAP_SSSZ(capabilities); + mpc8xxx_spi_write_reg(®_base->slvsel, 0xffffffff); + } + master->num_chipselect = mpc8xxx_spi->native_chipselects; + pdata->cs_control = fsl_spi_grlib_cs_control; +} + +static struct spi_master * fsl_spi_probe(struct device *dev, + struct resource *mem, unsigned int irq) +{ + struct fsl_spi_platform_data *pdata = dev_get_platdata(dev); + struct spi_master *master; + struct mpc8xxx_spi *mpc8xxx_spi; + struct fsl_spi_reg *reg_base; + u32 regval; + int ret = 0; + + master = spi_alloc_master(dev, sizeof(struct mpc8xxx_spi)); + if (master == NULL) { + ret = -ENOMEM; + goto err; + } + + dev_set_drvdata(dev, master); + + mpc8xxx_spi_probe(dev, mem, irq); + + master->setup = fsl_spi_setup; + master->cleanup = fsl_spi_cleanup; + master->transfer_one_message = fsl_spi_do_one_msg; + + mpc8xxx_spi = spi_master_get_devdata(master); + mpc8xxx_spi->spi_remove = fsl_spi_remove; + mpc8xxx_spi->max_bits_per_word = 32; + mpc8xxx_spi->type = fsl_spi_get_type(dev); + + ret = fsl_spi_cpm_init(mpc8xxx_spi); + if (ret) + goto err_cpm_init; + + mpc8xxx_spi->reg_base = ioremap(mem->start, resource_size(mem)); + if (mpc8xxx_spi->reg_base == NULL) { + ret = -ENOMEM; + goto err_ioremap; + } + + if (mpc8xxx_spi->type == TYPE_GRLIB) + fsl_spi_grlib_probe(dev); + + master->bits_per_word_mask = + (SPI_BPW_RANGE_MASK(4, 16) | SPI_BPW_MASK(32)) & + SPI_BPW_RANGE_MASK(1, mpc8xxx_spi->max_bits_per_word); + + if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE) + mpc8xxx_spi->set_shifts = fsl_spi_qe_cpu_set_shifts; + + if (mpc8xxx_spi->set_shifts) + /* 8 bits per word and MSB first */ + mpc8xxx_spi->set_shifts(&mpc8xxx_spi->rx_shift, + &mpc8xxx_spi->tx_shift, 8, 1); + + /* Register for SPI Interrupt */ + ret = request_irq(mpc8xxx_spi->irq, fsl_spi_irq, + 0, "fsl_spi", mpc8xxx_spi); + + if (ret != 0) + goto free_irq; + + reg_base = mpc8xxx_spi->reg_base; + + /* SPI controller initializations */ + mpc8xxx_spi_write_reg(®_base->mode, 0); + mpc8xxx_spi_write_reg(®_base->mask, 0); + mpc8xxx_spi_write_reg(®_base->command, 0); + mpc8xxx_spi_write_reg(®_base->event, 0xffffffff); + + /* Enable SPI interface */ + regval = pdata->initial_spmode | SPMODE_INIT_VAL | SPMODE_ENABLE; + if (mpc8xxx_spi->max_bits_per_word < 8) { + regval &= ~SPMODE_LEN(0xF); + regval |= SPMODE_LEN(mpc8xxx_spi->max_bits_per_word - 1); + } + if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE) + regval |= SPMODE_OP; + + mpc8xxx_spi_write_reg(®_base->mode, regval); + + ret = spi_register_master(master); + if (ret < 0) + goto unreg_master; + + dev_info(dev, "at 0x%p (irq = %d), %s mode\n", reg_base, + mpc8xxx_spi->irq, mpc8xxx_spi_strmode(mpc8xxx_spi->flags)); + + return master; + +unreg_master: + free_irq(mpc8xxx_spi->irq, mpc8xxx_spi); +free_irq: + iounmap(mpc8xxx_spi->reg_base); +err_ioremap: + fsl_spi_cpm_free(mpc8xxx_spi); +err_cpm_init: + spi_master_put(master); +err: + return ERR_PTR(ret); +} + +static void fsl_spi_cs_control(struct spi_device *spi, bool on) +{ + struct device *dev = spi->dev.parent->parent; + struct fsl_spi_platform_data *pdata = dev_get_platdata(dev); + struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(pdata); + u16 cs = spi->chip_select; + int gpio = pinfo->gpios[cs]; + bool alow = pinfo->alow_flags[cs]; + + gpio_set_value(gpio, on ^ alow); +} + +static int of_fsl_spi_get_chipselects(struct device *dev) +{ + struct device_node *np = dev->of_node; + struct fsl_spi_platform_data *pdata = dev_get_platdata(dev); + struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(pdata); + int ngpios; + int i = 0; + int ret; + + ngpios = of_gpio_count(np); + if (ngpios <= 0) { + /* + * SPI w/o chip-select line. One SPI device is still permitted + * though. + */ + pdata->max_chipselect = 1; + return 0; + } + + pinfo->gpios = kmalloc(ngpios * sizeof(*pinfo->gpios), GFP_KERNEL); + if (!pinfo->gpios) + return -ENOMEM; + memset(pinfo->gpios, -1, ngpios * sizeof(*pinfo->gpios)); + + pinfo->alow_flags = kzalloc(ngpios * sizeof(*pinfo->alow_flags), + GFP_KERNEL); + if (!pinfo->alow_flags) { + ret = -ENOMEM; + goto err_alloc_flags; + } + + for (; i < ngpios; i++) { + int gpio; + enum of_gpio_flags flags; + + gpio = of_get_gpio_flags(np, i, &flags); + if (!gpio_is_valid(gpio)) { + dev_err(dev, "invalid gpio #%d: %d\n", i, gpio); + ret = gpio; + goto err_loop; + } + + ret = gpio_request(gpio, dev_name(dev)); + if (ret) { + dev_err(dev, "can't request gpio #%d: %d\n", i, ret); + goto err_loop; + } + + pinfo->gpios[i] = gpio; + pinfo->alow_flags[i] = flags & OF_GPIO_ACTIVE_LOW; + + ret = gpio_direction_output(pinfo->gpios[i], + pinfo->alow_flags[i]); + if (ret) { + dev_err(dev, "can't set output direction for gpio " + "#%d: %d\n", i, ret); + goto err_loop; + } + } + + pdata->max_chipselect = ngpios; + pdata->cs_control = fsl_spi_cs_control; + + return 0; + +err_loop: + while (i >= 0) { + if (gpio_is_valid(pinfo->gpios[i])) + gpio_free(pinfo->gpios[i]); + i--; + } + + kfree(pinfo->alow_flags); + pinfo->alow_flags = NULL; +err_alloc_flags: + kfree(pinfo->gpios); + pinfo->gpios = NULL; + return ret; +} + +static int of_fsl_spi_free_chipselects(struct device *dev) +{ + struct fsl_spi_platform_data *pdata = dev_get_platdata(dev); + struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(pdata); + int i; + + if (!pinfo->gpios) + return 0; + + for (i = 0; i < pdata->max_chipselect; i++) { + if (gpio_is_valid(pinfo->gpios[i])) + gpio_free(pinfo->gpios[i]); + } + + kfree(pinfo->gpios); + kfree(pinfo->alow_flags); + return 0; +} + +static int of_fsl_spi_probe(struct platform_device *ofdev) +{ + struct device *dev = &ofdev->dev; + struct device_node *np = ofdev->dev.of_node; + struct spi_master *master; + struct resource mem; + int irq, type; + int ret = -ENOMEM; + + ret = of_mpc8xxx_spi_probe(ofdev); + if (ret) + return ret; + + type = fsl_spi_get_type(&ofdev->dev); + if (type == TYPE_FSL) { + ret = of_fsl_spi_get_chipselects(dev); + if (ret) + goto err; + } + + ret = of_address_to_resource(np, 0, &mem); + if (ret) + goto err; + + irq = irq_of_parse_and_map(np, 0); + if (!irq) { + ret = -EINVAL; + goto err; + } + + master = fsl_spi_probe(dev, &mem, irq); + if (IS_ERR(master)) { + ret = PTR_ERR(master); + goto err; + } + + return 0; + +err: + if (type == TYPE_FSL) + of_fsl_spi_free_chipselects(dev); + return ret; +} + +static int of_fsl_spi_remove(struct platform_device *ofdev) +{ + struct spi_master *master = platform_get_drvdata(ofdev); + struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(master); + int ret; + + ret = mpc8xxx_spi_remove(&ofdev->dev); + if (ret) + return ret; + if (mpc8xxx_spi->type == TYPE_FSL) + of_fsl_spi_free_chipselects(&ofdev->dev); + return 0; +} + +static struct platform_driver of_fsl_spi_driver = { + .driver = { + .name = "fsl_spi", + .of_match_table = of_fsl_spi_match, + }, + .probe = of_fsl_spi_probe, + .remove = of_fsl_spi_remove, +}; + +#ifdef CONFIG_MPC832x_RDB +/* + * XXX XXX XXX + * This is "legacy" platform driver, was used by the MPC8323E-RDB boards + * only. The driver should go away soon, since newer MPC8323E-RDB's device + * tree can work with OpenFirmware driver. But for now we support old trees + * as well. + */ +static int plat_mpc8xxx_spi_probe(struct platform_device *pdev) +{ + struct resource *mem; + int irq; + struct spi_master *master; + + if (!dev_get_platdata(&pdev->dev)) + return -EINVAL; + + mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!mem) + return -EINVAL; + + irq = platform_get_irq(pdev, 0); + if (irq <= 0) + return -EINVAL; + + master = fsl_spi_probe(&pdev->dev, mem, irq); + return PTR_ERR_OR_ZERO(master); +} + +static int plat_mpc8xxx_spi_remove(struct platform_device *pdev) +{ + return mpc8xxx_spi_remove(&pdev->dev); +} + +MODULE_ALIAS("platform:mpc8xxx_spi"); +static struct platform_driver mpc8xxx_spi_driver = { + .probe = plat_mpc8xxx_spi_probe, + .remove = plat_mpc8xxx_spi_remove, + .driver = { + .name = "mpc8xxx_spi", + }, +}; + +static bool legacy_driver_failed; + +static void __init legacy_driver_register(void) +{ + legacy_driver_failed = platform_driver_register(&mpc8xxx_spi_driver); +} + +static void __exit legacy_driver_unregister(void) +{ + if (legacy_driver_failed) + return; + platform_driver_unregister(&mpc8xxx_spi_driver); +} +#else +static void __init legacy_driver_register(void) {} +static void __exit legacy_driver_unregister(void) {} +#endif /* CONFIG_MPC832x_RDB */ + +static int __init fsl_spi_init(void) +{ + legacy_driver_register(); + return platform_driver_register(&of_fsl_spi_driver); +} +module_init(fsl_spi_init); + +static void __exit fsl_spi_exit(void) +{ + platform_driver_unregister(&of_fsl_spi_driver); + legacy_driver_unregister(); +} +module_exit(fsl_spi_exit); + +MODULE_AUTHOR("Kumar Gala"); +MODULE_DESCRIPTION("Simple Freescale SPI Driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/spi/spi-fsl-spi.h b/drivers/spi/spi-fsl-spi.h new file mode 100644 index 000000000..9a6dae00e --- /dev/null +++ b/drivers/spi/spi-fsl-spi.h @@ -0,0 +1,72 @@ +/* + * Freescale SPI controller driver. + * + * Maintainer: Kumar Gala + * + * Copyright (C) 2006 Polycom, Inc. + * Copyright 2010 Freescale Semiconductor, Inc. + * + * CPM SPI and QE buffer descriptors mode support: + * Copyright (c) 2009 MontaVista Software, Inc. + * Author: Anton Vorontsov <avorontsov@ru.mvista.com> + * + * GRLIB support: + * Copyright (c) 2012 Aeroflex Gaisler AB. + * Author: Andreas Larsson <andreas@gaisler.com> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + */ + +#ifndef __SPI_FSL_SPI_H__ +#define __SPI_FSL_SPI_H__ + +/* SPI Controller registers */ +struct fsl_spi_reg { + __be32 cap; /* TYPE_GRLIB specific */ + u8 res1[0x1C]; + __be32 mode; + __be32 event; + __be32 mask; + __be32 command; + __be32 transmit; + __be32 receive; + __be32 slvsel; /* TYPE_GRLIB specific */ +}; + +/* SPI Controller mode register definitions */ +#define SPMODE_LOOP (1 << 30) +#define SPMODE_CI_INACTIVEHIGH (1 << 29) +#define SPMODE_CP_BEGIN_EDGECLK (1 << 28) +#define SPMODE_DIV16 (1 << 27) +#define SPMODE_REV (1 << 26) +#define SPMODE_MS (1 << 25) +#define SPMODE_ENABLE (1 << 24) +#define SPMODE_LEN(x) ((x) << 20) +#define SPMODE_PM(x) ((x) << 16) +#define SPMODE_OP (1 << 14) +#define SPMODE_CG(x) ((x) << 7) + +/* TYPE_GRLIB SPI Controller capability register definitions */ +#define SPCAP_SSEN(x) (((x) >> 16) & 0x1) +#define SPCAP_SSSZ(x) (((x) >> 24) & 0xff) +#define SPCAP_MAXWLEN(x) (((x) >> 20) & 0xf) + +/* + * Default for SPI Mode: + * SPI MODE 0 (inactive low, phase middle, MSB, 8-bit length, slow clk + */ +#define SPMODE_INIT_VAL (SPMODE_CI_INACTIVEHIGH | SPMODE_DIV16 | SPMODE_REV | \ + SPMODE_MS | SPMODE_LEN(7) | SPMODE_PM(0xf)) + +/* SPIE register values */ +#define SPIE_NE 0x00000200 /* Not empty */ +#define SPIE_NF 0x00000100 /* Not full */ + +/* SPIM register values */ +#define SPIM_NE 0x00000200 /* Not empty */ +#define SPIM_NF 0x00000100 /* Not full */ + +#endif /* __SPI_FSL_SPI_H__ */ diff --git a/drivers/spi/spi-gpio.c b/drivers/spi/spi-gpio.c new file mode 100644 index 000000000..1c34c9314 --- /dev/null +++ b/drivers/spi/spi-gpio.c @@ -0,0 +1,547 @@ +/* + * SPI master driver using generic bitbanged GPIO + * + * Copyright (C) 2006,2008 David Brownell + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/gpio.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/of_gpio.h> + +#include <linux/spi/spi.h> +#include <linux/spi/spi_bitbang.h> +#include <linux/spi/spi_gpio.h> + + +/* + * This bitbanging SPI master driver should help make systems usable + * when a native hardware SPI engine is not available, perhaps because + * its driver isn't yet working or because the I/O pins it requires + * are used for other purposes. + * + * platform_device->driver_data ... points to spi_gpio + * + * spi->controller_state ... reserved for bitbang framework code + * spi->controller_data ... holds chipselect GPIO + * + * spi->master->dev.driver_data ... points to spi_gpio->bitbang + */ + +struct spi_gpio { + struct spi_bitbang bitbang; + struct spi_gpio_platform_data pdata; + struct platform_device *pdev; + unsigned long cs_gpios[0]; +}; + +/*----------------------------------------------------------------------*/ + +/* + * Because the overhead of going through four GPIO procedure calls + * per transferred bit can make performance a problem, this code + * is set up so that you can use it in either of two ways: + * + * - The slow generic way: set up platform_data to hold the GPIO + * numbers used for MISO/MOSI/SCK, and issue procedure calls for + * each of them. This driver can handle several such busses. + * + * - The quicker inlined way: only helps with platform GPIO code + * that inlines operations for constant GPIOs. This can give + * you tight (fast!) inner loops, but each such bus needs a + * new driver. You'll define a new C file, with Makefile and + * Kconfig support; the C code can be a total of six lines: + * + * #define DRIVER_NAME "myboard_spi2" + * #define SPI_MISO_GPIO 119 + * #define SPI_MOSI_GPIO 120 + * #define SPI_SCK_GPIO 121 + * #define SPI_N_CHIPSEL 4 + * #include "spi-gpio.c" + */ + +#ifndef DRIVER_NAME +#define DRIVER_NAME "spi_gpio" + +#define GENERIC_BITBANG /* vs tight inlines */ + +/* all functions referencing these symbols must define pdata */ +#define SPI_MISO_GPIO ((pdata)->miso) +#define SPI_MOSI_GPIO ((pdata)->mosi) +#define SPI_SCK_GPIO ((pdata)->sck) + +#define SPI_N_CHIPSEL ((pdata)->num_chipselect) + +#endif + +/*----------------------------------------------------------------------*/ + +static inline struct spi_gpio *__pure +spi_to_spi_gpio(const struct spi_device *spi) +{ + const struct spi_bitbang *bang; + struct spi_gpio *spi_gpio; + + bang = spi_master_get_devdata(spi->master); + spi_gpio = container_of(bang, struct spi_gpio, bitbang); + return spi_gpio; +} + +static inline struct spi_gpio_platform_data *__pure +spi_to_pdata(const struct spi_device *spi) +{ + return &spi_to_spi_gpio(spi)->pdata; +} + +/* this is #defined to avoid unused-variable warnings when inlining */ +#define pdata spi_to_pdata(spi) + +static inline void setsck(const struct spi_device *spi, int is_on) +{ + gpio_set_value_cansleep(SPI_SCK_GPIO, is_on); +} + +static inline void setmosi(const struct spi_device *spi, int is_on) +{ + gpio_set_value_cansleep(SPI_MOSI_GPIO, is_on); +} + +static inline int getmiso(const struct spi_device *spi) +{ + return !!gpio_get_value_cansleep(SPI_MISO_GPIO); +} + +#undef pdata + +/* + * NOTE: this clocks "as fast as we can". It "should" be a function of the + * requested device clock. Software overhead means we usually have trouble + * reaching even one Mbit/sec (except when we can inline bitops), so for now + * we'll just assume we never need additional per-bit slowdowns. + */ +#define spidelay(nsecs) do {} while (0) + +#include "spi-bitbang-txrx.h" + +/* + * These functions can leverage inline expansion of GPIO calls to shrink + * costs for a txrx bit, often by factors of around ten (by instruction + * count). That is particularly visible for larger word sizes, but helps + * even with default 8-bit words. + * + * REVISIT overheads calling these functions for each word also have + * significant performance costs. Having txrx_bufs() calls that inline + * the txrx_word() logic would help performance, e.g. on larger blocks + * used with flash storage or MMC/SD. There should also be ways to make + * GCC be less stupid about reloading registers inside the I/O loops, + * even without inlined GPIO calls; __attribute__((hot)) on GCC 4.3? + */ + +static u32 spi_gpio_txrx_word_mode0(struct spi_device *spi, + unsigned nsecs, u32 word, u8 bits) +{ + return bitbang_txrx_be_cpha0(spi, nsecs, 0, 0, word, bits); +} + +static u32 spi_gpio_txrx_word_mode1(struct spi_device *spi, + unsigned nsecs, u32 word, u8 bits) +{ + return bitbang_txrx_be_cpha1(spi, nsecs, 0, 0, word, bits); +} + +static u32 spi_gpio_txrx_word_mode2(struct spi_device *spi, + unsigned nsecs, u32 word, u8 bits) +{ + return bitbang_txrx_be_cpha0(spi, nsecs, 1, 0, word, bits); +} + +static u32 spi_gpio_txrx_word_mode3(struct spi_device *spi, + unsigned nsecs, u32 word, u8 bits) +{ + return bitbang_txrx_be_cpha1(spi, nsecs, 1, 0, word, bits); +} + +/* + * These functions do not call setmosi or getmiso if respective flag + * (SPI_MASTER_NO_RX or SPI_MASTER_NO_TX) is set, so they are safe to + * call when such pin is not present or defined in the controller. + * A separate set of callbacks is defined to get highest possible + * speed in the generic case (when both MISO and MOSI lines are + * available), as optimiser will remove the checks when argument is + * constant. + */ + +static u32 spi_gpio_spec_txrx_word_mode0(struct spi_device *spi, + unsigned nsecs, u32 word, u8 bits) +{ + unsigned flags = spi->master->flags; + return bitbang_txrx_be_cpha0(spi, nsecs, 0, flags, word, bits); +} + +static u32 spi_gpio_spec_txrx_word_mode1(struct spi_device *spi, + unsigned nsecs, u32 word, u8 bits) +{ + unsigned flags = spi->master->flags; + return bitbang_txrx_be_cpha1(spi, nsecs, 0, flags, word, bits); +} + +static u32 spi_gpio_spec_txrx_word_mode2(struct spi_device *spi, + unsigned nsecs, u32 word, u8 bits) +{ + unsigned flags = spi->master->flags; + return bitbang_txrx_be_cpha0(spi, nsecs, 1, flags, word, bits); +} + +static u32 spi_gpio_spec_txrx_word_mode3(struct spi_device *spi, + unsigned nsecs, u32 word, u8 bits) +{ + unsigned flags = spi->master->flags; + return bitbang_txrx_be_cpha1(spi, nsecs, 1, flags, word, bits); +} + +/*----------------------------------------------------------------------*/ + +static void spi_gpio_chipselect(struct spi_device *spi, int is_active) +{ + struct spi_gpio *spi_gpio = spi_to_spi_gpio(spi); + unsigned long cs = spi_gpio->cs_gpios[spi->chip_select]; + + /* set initial clock polarity */ + if (is_active) + setsck(spi, spi->mode & SPI_CPOL); + + if (cs != SPI_GPIO_NO_CHIPSELECT) { + /* SPI is normally active-low */ + gpio_set_value_cansleep(cs, (spi->mode & SPI_CS_HIGH) ? is_active : !is_active); + } +} + +static int spi_gpio_setup(struct spi_device *spi) +{ + unsigned long cs; + int status = 0; + struct spi_gpio *spi_gpio = spi_to_spi_gpio(spi); + struct device_node *np = spi->master->dev.of_node; + + if (np) { + /* + * In DT environments, the CS GPIOs have already been + * initialized from the "cs-gpios" property of the node. + */ + cs = spi_gpio->cs_gpios[spi->chip_select]; + } else { + /* + * ... otherwise, take it from spi->controller_data + */ + cs = (uintptr_t) spi->controller_data; + } + + if (!spi->controller_state) { + if (cs != SPI_GPIO_NO_CHIPSELECT) { + status = gpio_request(cs, dev_name(&spi->dev)); + if (status) + return status; + status = gpio_direction_output(cs, + !(spi->mode & SPI_CS_HIGH)); + } + } + if (!status) { + /* in case it was initialized from static board data */ + spi_gpio->cs_gpios[spi->chip_select] = cs; + status = spi_bitbang_setup(spi); + } + + if (status) { + if (!spi->controller_state && cs != SPI_GPIO_NO_CHIPSELECT) + gpio_free(cs); + } + return status; +} + +static void spi_gpio_cleanup(struct spi_device *spi) +{ + struct spi_gpio *spi_gpio = spi_to_spi_gpio(spi); + unsigned long cs = spi_gpio->cs_gpios[spi->chip_select]; + + if (cs != SPI_GPIO_NO_CHIPSELECT) + gpio_free(cs); + spi_bitbang_cleanup(spi); +} + +static int spi_gpio_alloc(unsigned pin, const char *label, bool is_in) +{ + int value; + + value = gpio_request(pin, label); + if (value == 0) { + if (is_in) + value = gpio_direction_input(pin); + else + value = gpio_direction_output(pin, 0); + } + return value; +} + +static int spi_gpio_request(struct spi_gpio_platform_data *pdata, + const char *label, u16 *res_flags) +{ + int value; + + /* NOTE: SPI_*_GPIO symbols may reference "pdata" */ + + if (SPI_MOSI_GPIO != SPI_GPIO_NO_MOSI) { + value = spi_gpio_alloc(SPI_MOSI_GPIO, label, false); + if (value) + goto done; + } else { + /* HW configuration without MOSI pin */ + *res_flags |= SPI_MASTER_NO_TX; + } + + if (SPI_MISO_GPIO != SPI_GPIO_NO_MISO) { + value = spi_gpio_alloc(SPI_MISO_GPIO, label, true); + if (value) + goto free_mosi; + } else { + /* HW configuration without MISO pin */ + *res_flags |= SPI_MASTER_NO_RX; + } + + value = spi_gpio_alloc(SPI_SCK_GPIO, label, false); + if (value) + goto free_miso; + + goto done; + +free_miso: + if (SPI_MISO_GPIO != SPI_GPIO_NO_MISO) + gpio_free(SPI_MISO_GPIO); +free_mosi: + if (SPI_MOSI_GPIO != SPI_GPIO_NO_MOSI) + gpio_free(SPI_MOSI_GPIO); +done: + return value; +} + +#ifdef CONFIG_OF +static const struct of_device_id spi_gpio_dt_ids[] = { + { .compatible = "spi-gpio" }, + {} +}; +MODULE_DEVICE_TABLE(of, spi_gpio_dt_ids); + +static int spi_gpio_probe_dt(struct platform_device *pdev) +{ + int ret; + u32 tmp; + struct spi_gpio_platform_data *pdata; + struct device_node *np = pdev->dev.of_node; + const struct of_device_id *of_id = + of_match_device(spi_gpio_dt_ids, &pdev->dev); + + if (!of_id) + return 0; + + pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL); + if (!pdata) + return -ENOMEM; + + ret = of_get_named_gpio(np, "gpio-sck", 0); + if (ret < 0) { + dev_err(&pdev->dev, "gpio-sck property not found\n"); + goto error_free; + } + pdata->sck = ret; + + ret = of_get_named_gpio(np, "gpio-miso", 0); + if (ret < 0) { + dev_info(&pdev->dev, "gpio-miso property not found, switching to no-rx mode\n"); + pdata->miso = SPI_GPIO_NO_MISO; + } else + pdata->miso = ret; + + ret = of_get_named_gpio(np, "gpio-mosi", 0); + if (ret < 0) { + dev_info(&pdev->dev, "gpio-mosi property not found, switching to no-tx mode\n"); + pdata->mosi = SPI_GPIO_NO_MOSI; + } else + pdata->mosi = ret; + + ret = of_property_read_u32(np, "num-chipselects", &tmp); + if (ret < 0) { + dev_err(&pdev->dev, "num-chipselects property not found\n"); + goto error_free; + } + + pdata->num_chipselect = tmp; + pdev->dev.platform_data = pdata; + + return 1; + +error_free: + devm_kfree(&pdev->dev, pdata); + return ret; +} +#else +static inline int spi_gpio_probe_dt(struct platform_device *pdev) +{ + return 0; +} +#endif + +static int spi_gpio_probe(struct platform_device *pdev) +{ + int status; + struct spi_master *master; + struct spi_gpio *spi_gpio; + struct spi_gpio_platform_data *pdata; + u16 master_flags = 0; + bool use_of = 0; + int num_devices; + + status = spi_gpio_probe_dt(pdev); + if (status < 0) + return status; + if (status > 0) + use_of = 1; + + pdata = dev_get_platdata(&pdev->dev); +#ifdef GENERIC_BITBANG + if (!pdata || (!use_of && !pdata->num_chipselect)) + return -ENODEV; +#endif + + if (use_of && !SPI_N_CHIPSEL) + num_devices = 1; + else + num_devices = SPI_N_CHIPSEL; + + status = spi_gpio_request(pdata, dev_name(&pdev->dev), &master_flags); + if (status < 0) + return status; + + master = spi_alloc_master(&pdev->dev, sizeof(*spi_gpio) + + (sizeof(unsigned long) * num_devices)); + if (!master) { + status = -ENOMEM; + goto gpio_free; + } + spi_gpio = spi_master_get_devdata(master); + platform_set_drvdata(pdev, spi_gpio); + + spi_gpio->pdev = pdev; + if (pdata) + spi_gpio->pdata = *pdata; + + master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32); + master->flags = master_flags; + master->bus_num = pdev->id; + master->num_chipselect = num_devices; + master->setup = spi_gpio_setup; + master->cleanup = spi_gpio_cleanup; +#ifdef CONFIG_OF + master->dev.of_node = pdev->dev.of_node; + + if (use_of) { + int i; + struct device_node *np = pdev->dev.of_node; + + /* + * In DT environments, take the CS GPIO from the "cs-gpios" + * property of the node. + */ + + if (!SPI_N_CHIPSEL) + spi_gpio->cs_gpios[0] = SPI_GPIO_NO_CHIPSELECT; + else + for (i = 0; i < SPI_N_CHIPSEL; i++) { + status = of_get_named_gpio(np, "cs-gpios", i); + if (status < 0) { + dev_err(&pdev->dev, + "invalid cs-gpios property\n"); + goto gpio_free; + } + spi_gpio->cs_gpios[i] = status; + } + } +#endif + + spi_gpio->bitbang.master = master; + spi_gpio->bitbang.chipselect = spi_gpio_chipselect; + + if ((master_flags & (SPI_MASTER_NO_TX | SPI_MASTER_NO_RX)) == 0) { + spi_gpio->bitbang.txrx_word[SPI_MODE_0] = spi_gpio_txrx_word_mode0; + spi_gpio->bitbang.txrx_word[SPI_MODE_1] = spi_gpio_txrx_word_mode1; + spi_gpio->bitbang.txrx_word[SPI_MODE_2] = spi_gpio_txrx_word_mode2; + spi_gpio->bitbang.txrx_word[SPI_MODE_3] = spi_gpio_txrx_word_mode3; + } else { + spi_gpio->bitbang.txrx_word[SPI_MODE_0] = spi_gpio_spec_txrx_word_mode0; + spi_gpio->bitbang.txrx_word[SPI_MODE_1] = spi_gpio_spec_txrx_word_mode1; + spi_gpio->bitbang.txrx_word[SPI_MODE_2] = spi_gpio_spec_txrx_word_mode2; + spi_gpio->bitbang.txrx_word[SPI_MODE_3] = spi_gpio_spec_txrx_word_mode3; + } + spi_gpio->bitbang.setup_transfer = spi_bitbang_setup_transfer; + spi_gpio->bitbang.flags = SPI_CS_HIGH; + + status = spi_bitbang_start(&spi_gpio->bitbang); + if (status < 0) { +gpio_free: + if (SPI_MISO_GPIO != SPI_GPIO_NO_MISO) + gpio_free(SPI_MISO_GPIO); + if (SPI_MOSI_GPIO != SPI_GPIO_NO_MOSI) + gpio_free(SPI_MOSI_GPIO); + gpio_free(SPI_SCK_GPIO); + spi_master_put(master); + } + + return status; +} + +static int spi_gpio_remove(struct platform_device *pdev) +{ + struct spi_gpio *spi_gpio; + struct spi_gpio_platform_data *pdata; + + spi_gpio = platform_get_drvdata(pdev); + pdata = dev_get_platdata(&pdev->dev); + + /* stop() unregisters child devices too */ + spi_bitbang_stop(&spi_gpio->bitbang); + + if (SPI_MISO_GPIO != SPI_GPIO_NO_MISO) + gpio_free(SPI_MISO_GPIO); + if (SPI_MOSI_GPIO != SPI_GPIO_NO_MOSI) + gpio_free(SPI_MOSI_GPIO); + gpio_free(SPI_SCK_GPIO); + spi_master_put(spi_gpio->bitbang.master); + + return 0; +} + +MODULE_ALIAS("platform:" DRIVER_NAME); + +static struct platform_driver spi_gpio_driver = { + .driver = { + .name = DRIVER_NAME, + .of_match_table = of_match_ptr(spi_gpio_dt_ids), + }, + .probe = spi_gpio_probe, + .remove = spi_gpio_remove, +}; +module_platform_driver(spi_gpio_driver); + +MODULE_DESCRIPTION("SPI master driver using generic bitbanged GPIO "); +MODULE_AUTHOR("David Brownell"); +MODULE_LICENSE("GPL"); diff --git a/drivers/spi/spi-img-spfi.c b/drivers/spi/spi-img-spfi.c new file mode 100644 index 000000000..788e2b176 --- /dev/null +++ b/drivers/spi/spi-img-spfi.c @@ -0,0 +1,759 @@ +/* + * IMG SPFI controller driver + * + * Copyright (C) 2007,2008,2013 Imagination Technologies Ltd. + * Copyright (C) 2014 Google, Inc. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + */ + +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/dmaengine.h> +#include <linux/gpio.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/irq.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/scatterlist.h> +#include <linux/slab.h> +#include <linux/spi/spi.h> +#include <linux/spinlock.h> + +#define SPFI_DEVICE_PARAMETER(x) (0x00 + 0x4 * (x)) +#define SPFI_DEVICE_PARAMETER_BITCLK_SHIFT 24 +#define SPFI_DEVICE_PARAMETER_BITCLK_MASK 0xff +#define SPFI_DEVICE_PARAMETER_CSSETUP_SHIFT 16 +#define SPFI_DEVICE_PARAMETER_CSSETUP_MASK 0xff +#define SPFI_DEVICE_PARAMETER_CSHOLD_SHIFT 8 +#define SPFI_DEVICE_PARAMETER_CSHOLD_MASK 0xff +#define SPFI_DEVICE_PARAMETER_CSDELAY_SHIFT 0 +#define SPFI_DEVICE_PARAMETER_CSDELAY_MASK 0xff + +#define SPFI_CONTROL 0x14 +#define SPFI_CONTROL_CONTINUE BIT(12) +#define SPFI_CONTROL_SOFT_RESET BIT(11) +#define SPFI_CONTROL_SEND_DMA BIT(10) +#define SPFI_CONTROL_GET_DMA BIT(9) +#define SPFI_CONTROL_TMODE_SHIFT 5 +#define SPFI_CONTROL_TMODE_MASK 0x7 +#define SPFI_CONTROL_TMODE_SINGLE 0 +#define SPFI_CONTROL_TMODE_DUAL 1 +#define SPFI_CONTROL_TMODE_QUAD 2 +#define SPFI_CONTROL_SPFI_EN BIT(0) + +#define SPFI_TRANSACTION 0x18 +#define SPFI_TRANSACTION_TSIZE_SHIFT 16 +#define SPFI_TRANSACTION_TSIZE_MASK 0xffff + +#define SPFI_PORT_STATE 0x1c +#define SPFI_PORT_STATE_DEV_SEL_SHIFT 20 +#define SPFI_PORT_STATE_DEV_SEL_MASK 0x7 +#define SPFI_PORT_STATE_CK_POL(x) BIT(19 - (x)) +#define SPFI_PORT_STATE_CK_PHASE(x) BIT(14 - (x)) + +#define SPFI_TX_32BIT_VALID_DATA 0x20 +#define SPFI_TX_8BIT_VALID_DATA 0x24 +#define SPFI_RX_32BIT_VALID_DATA 0x28 +#define SPFI_RX_8BIT_VALID_DATA 0x2c + +#define SPFI_INTERRUPT_STATUS 0x30 +#define SPFI_INTERRUPT_ENABLE 0x34 +#define SPFI_INTERRUPT_CLEAR 0x38 +#define SPFI_INTERRUPT_IACCESS BIT(12) +#define SPFI_INTERRUPT_GDEX8BIT BIT(11) +#define SPFI_INTERRUPT_ALLDONETRIG BIT(9) +#define SPFI_INTERRUPT_GDFUL BIT(8) +#define SPFI_INTERRUPT_GDHF BIT(7) +#define SPFI_INTERRUPT_GDEX32BIT BIT(6) +#define SPFI_INTERRUPT_GDTRIG BIT(5) +#define SPFI_INTERRUPT_SDFUL BIT(3) +#define SPFI_INTERRUPT_SDHF BIT(2) +#define SPFI_INTERRUPT_SDE BIT(1) +#define SPFI_INTERRUPT_SDTRIG BIT(0) + +/* + * There are four parallel FIFOs of 16 bytes each. The word buffer + * (*_32BIT_VALID_DATA) accesses all four FIFOs at once, resulting in an + * effective FIFO size of 64 bytes. The byte buffer (*_8BIT_VALID_DATA) + * accesses only a single FIFO, resulting in an effective FIFO size of + * 16 bytes. + */ +#define SPFI_32BIT_FIFO_SIZE 64 +#define SPFI_8BIT_FIFO_SIZE 16 + +struct img_spfi { + struct device *dev; + struct spi_master *master; + spinlock_t lock; + + void __iomem *regs; + phys_addr_t phys; + int irq; + struct clk *spfi_clk; + struct clk *sys_clk; + + struct dma_chan *rx_ch; + struct dma_chan *tx_ch; + bool tx_dma_busy; + bool rx_dma_busy; +}; + +static inline u32 spfi_readl(struct img_spfi *spfi, u32 reg) +{ + return readl(spfi->regs + reg); +} + +static inline void spfi_writel(struct img_spfi *spfi, u32 val, u32 reg) +{ + writel(val, spfi->regs + reg); +} + +static inline void spfi_start(struct img_spfi *spfi) +{ + u32 val; + + val = spfi_readl(spfi, SPFI_CONTROL); + val |= SPFI_CONTROL_SPFI_EN; + spfi_writel(spfi, val, SPFI_CONTROL); +} + +static inline void spfi_reset(struct img_spfi *spfi) +{ + spfi_writel(spfi, SPFI_CONTROL_SOFT_RESET, SPFI_CONTROL); + spfi_writel(spfi, 0, SPFI_CONTROL); +} + +static int spfi_wait_all_done(struct img_spfi *spfi) +{ + unsigned long timeout = jiffies + msecs_to_jiffies(50); + + while (time_before(jiffies, timeout)) { + u32 status = spfi_readl(spfi, SPFI_INTERRUPT_STATUS); + + if (status & SPFI_INTERRUPT_ALLDONETRIG) { + spfi_writel(spfi, SPFI_INTERRUPT_ALLDONETRIG, + SPFI_INTERRUPT_CLEAR); + return 0; + } + cpu_relax(); + } + + dev_err(spfi->dev, "Timed out waiting for transaction to complete\n"); + spfi_reset(spfi); + + return -ETIMEDOUT; +} + +static unsigned int spfi_pio_write32(struct img_spfi *spfi, const u32 *buf, + unsigned int max) +{ + unsigned int count = 0; + u32 status; + + while (count < max / 4) { + spfi_writel(spfi, SPFI_INTERRUPT_SDFUL, SPFI_INTERRUPT_CLEAR); + status = spfi_readl(spfi, SPFI_INTERRUPT_STATUS); + if (status & SPFI_INTERRUPT_SDFUL) + break; + spfi_writel(spfi, buf[count], SPFI_TX_32BIT_VALID_DATA); + count++; + } + + return count * 4; +} + +static unsigned int spfi_pio_write8(struct img_spfi *spfi, const u8 *buf, + unsigned int max) +{ + unsigned int count = 0; + u32 status; + + while (count < max) { + spfi_writel(spfi, SPFI_INTERRUPT_SDFUL, SPFI_INTERRUPT_CLEAR); + status = spfi_readl(spfi, SPFI_INTERRUPT_STATUS); + if (status & SPFI_INTERRUPT_SDFUL) + break; + spfi_writel(spfi, buf[count], SPFI_TX_8BIT_VALID_DATA); + count++; + } + + return count; +} + +static unsigned int spfi_pio_read32(struct img_spfi *spfi, u32 *buf, + unsigned int max) +{ + unsigned int count = 0; + u32 status; + + while (count < max / 4) { + spfi_writel(spfi, SPFI_INTERRUPT_GDEX32BIT, + SPFI_INTERRUPT_CLEAR); + status = spfi_readl(spfi, SPFI_INTERRUPT_STATUS); + if (!(status & SPFI_INTERRUPT_GDEX32BIT)) + break; + buf[count] = spfi_readl(spfi, SPFI_RX_32BIT_VALID_DATA); + count++; + } + + return count * 4; +} + +static unsigned int spfi_pio_read8(struct img_spfi *spfi, u8 *buf, + unsigned int max) +{ + unsigned int count = 0; + u32 status; + + while (count < max) { + spfi_writel(spfi, SPFI_INTERRUPT_GDEX8BIT, + SPFI_INTERRUPT_CLEAR); + status = spfi_readl(spfi, SPFI_INTERRUPT_STATUS); + if (!(status & SPFI_INTERRUPT_GDEX8BIT)) + break; + buf[count] = spfi_readl(spfi, SPFI_RX_8BIT_VALID_DATA); + count++; + } + + return count; +} + +static int img_spfi_start_pio(struct spi_master *master, + struct spi_device *spi, + struct spi_transfer *xfer) +{ + struct img_spfi *spfi = spi_master_get_devdata(spi->master); + unsigned int tx_bytes = 0, rx_bytes = 0; + const void *tx_buf = xfer->tx_buf; + void *rx_buf = xfer->rx_buf; + unsigned long timeout; + int ret; + + if (tx_buf) + tx_bytes = xfer->len; + if (rx_buf) + rx_bytes = xfer->len; + + spfi_start(spfi); + + timeout = jiffies + + msecs_to_jiffies(xfer->len * 8 * 1000 / xfer->speed_hz + 100); + while ((tx_bytes > 0 || rx_bytes > 0) && + time_before(jiffies, timeout)) { + unsigned int tx_count, rx_count; + + if (tx_bytes >= 4) + tx_count = spfi_pio_write32(spfi, tx_buf, tx_bytes); + else + tx_count = spfi_pio_write8(spfi, tx_buf, tx_bytes); + + if (rx_bytes >= 4) + rx_count = spfi_pio_read32(spfi, rx_buf, rx_bytes); + else + rx_count = spfi_pio_read8(spfi, rx_buf, rx_bytes); + + tx_buf += tx_count; + rx_buf += rx_count; + tx_bytes -= tx_count; + rx_bytes -= rx_count; + + cpu_relax(); + } + + ret = spfi_wait_all_done(spfi); + if (ret < 0) + return ret; + + if (rx_bytes > 0 || tx_bytes > 0) { + dev_err(spfi->dev, "PIO transfer timed out\n"); + return -ETIMEDOUT; + } + + return 0; +} + +static void img_spfi_dma_rx_cb(void *data) +{ + struct img_spfi *spfi = data; + unsigned long flags; + + spfi_wait_all_done(spfi); + + spin_lock_irqsave(&spfi->lock, flags); + spfi->rx_dma_busy = false; + if (!spfi->tx_dma_busy) + spi_finalize_current_transfer(spfi->master); + spin_unlock_irqrestore(&spfi->lock, flags); +} + +static void img_spfi_dma_tx_cb(void *data) +{ + struct img_spfi *spfi = data; + unsigned long flags; + + spfi_wait_all_done(spfi); + + spin_lock_irqsave(&spfi->lock, flags); + spfi->tx_dma_busy = false; + if (!spfi->rx_dma_busy) + spi_finalize_current_transfer(spfi->master); + spin_unlock_irqrestore(&spfi->lock, flags); +} + +static int img_spfi_start_dma(struct spi_master *master, + struct spi_device *spi, + struct spi_transfer *xfer) +{ + struct img_spfi *spfi = spi_master_get_devdata(spi->master); + struct dma_async_tx_descriptor *rxdesc = NULL, *txdesc = NULL; + struct dma_slave_config rxconf, txconf; + + spfi->rx_dma_busy = false; + spfi->tx_dma_busy = false; + + if (xfer->rx_buf) { + rxconf.direction = DMA_DEV_TO_MEM; + if (xfer->len % 4 == 0) { + rxconf.src_addr = spfi->phys + SPFI_RX_32BIT_VALID_DATA; + rxconf.src_addr_width = 4; + rxconf.src_maxburst = 4; + } else { + rxconf.src_addr = spfi->phys + SPFI_RX_8BIT_VALID_DATA; + rxconf.src_addr_width = 1; + rxconf.src_maxburst = 4; + } + dmaengine_slave_config(spfi->rx_ch, &rxconf); + + rxdesc = dmaengine_prep_slave_sg(spfi->rx_ch, xfer->rx_sg.sgl, + xfer->rx_sg.nents, + DMA_DEV_TO_MEM, + DMA_PREP_INTERRUPT); + if (!rxdesc) + goto stop_dma; + + rxdesc->callback = img_spfi_dma_rx_cb; + rxdesc->callback_param = spfi; + } + + if (xfer->tx_buf) { + txconf.direction = DMA_MEM_TO_DEV; + if (xfer->len % 4 == 0) { + txconf.dst_addr = spfi->phys + SPFI_TX_32BIT_VALID_DATA; + txconf.dst_addr_width = 4; + txconf.dst_maxburst = 4; + } else { + txconf.dst_addr = spfi->phys + SPFI_TX_8BIT_VALID_DATA; + txconf.dst_addr_width = 1; + txconf.dst_maxburst = 4; + } + dmaengine_slave_config(spfi->tx_ch, &txconf); + + txdesc = dmaengine_prep_slave_sg(spfi->tx_ch, xfer->tx_sg.sgl, + xfer->tx_sg.nents, + DMA_MEM_TO_DEV, + DMA_PREP_INTERRUPT); + if (!txdesc) + goto stop_dma; + + txdesc->callback = img_spfi_dma_tx_cb; + txdesc->callback_param = spfi; + } + + if (xfer->rx_buf) { + spfi->rx_dma_busy = true; + dmaengine_submit(rxdesc); + dma_async_issue_pending(spfi->rx_ch); + } + + spfi_start(spfi); + + if (xfer->tx_buf) { + spfi->tx_dma_busy = true; + dmaengine_submit(txdesc); + dma_async_issue_pending(spfi->tx_ch); + } + + return 1; + +stop_dma: + dmaengine_terminate_all(spfi->rx_ch); + dmaengine_terminate_all(spfi->tx_ch); + return -EIO; +} + +static void img_spfi_handle_err(struct spi_master *master, + struct spi_message *msg) +{ + struct img_spfi *spfi = spi_master_get_devdata(master); + unsigned long flags; + + /* + * Stop all DMA and reset the controller if the previous transaction + * timed-out and never completed it's DMA. + */ + spin_lock_irqsave(&spfi->lock, flags); + if (spfi->tx_dma_busy || spfi->rx_dma_busy) { + spfi->tx_dma_busy = false; + spfi->rx_dma_busy = false; + + dmaengine_terminate_all(spfi->tx_ch); + dmaengine_terminate_all(spfi->rx_ch); + } + spin_unlock_irqrestore(&spfi->lock, flags); +} + +static int img_spfi_prepare(struct spi_master *master, struct spi_message *msg) +{ + struct img_spfi *spfi = spi_master_get_devdata(master); + u32 val; + + val = spfi_readl(spfi, SPFI_PORT_STATE); + if (msg->spi->mode & SPI_CPHA) + val |= SPFI_PORT_STATE_CK_PHASE(msg->spi->chip_select); + else + val &= ~SPFI_PORT_STATE_CK_PHASE(msg->spi->chip_select); + if (msg->spi->mode & SPI_CPOL) + val |= SPFI_PORT_STATE_CK_POL(msg->spi->chip_select); + else + val &= ~SPFI_PORT_STATE_CK_POL(msg->spi->chip_select); + spfi_writel(spfi, val, SPFI_PORT_STATE); + + return 0; +} + +static int img_spfi_unprepare(struct spi_master *master, + struct spi_message *msg) +{ + struct img_spfi *spfi = spi_master_get_devdata(master); + + spfi_reset(spfi); + + return 0; +} + +static int img_spfi_setup(struct spi_device *spi) +{ + int ret; + + ret = gpio_request_one(spi->cs_gpio, (spi->mode & SPI_CS_HIGH) ? + GPIOF_OUT_INIT_LOW : GPIOF_OUT_INIT_HIGH, + dev_name(&spi->dev)); + if (ret) + dev_err(&spi->dev, "can't request chipselect gpio %d\n", + spi->cs_gpio); + + return ret; +} + +static void img_spfi_cleanup(struct spi_device *spi) +{ + gpio_free(spi->cs_gpio); +} + +static void img_spfi_config(struct spi_master *master, struct spi_device *spi, + struct spi_transfer *xfer) +{ + struct img_spfi *spfi = spi_master_get_devdata(spi->master); + u32 val, div; + + /* + * output = spfi_clk * (BITCLK / 512), where BITCLK must be a + * power of 2 up to 128 + */ + div = DIV_ROUND_UP(clk_get_rate(spfi->spfi_clk), xfer->speed_hz); + div = clamp(512 / (1 << get_count_order(div)), 1, 128); + + val = spfi_readl(spfi, SPFI_DEVICE_PARAMETER(spi->chip_select)); + val &= ~(SPFI_DEVICE_PARAMETER_BITCLK_MASK << + SPFI_DEVICE_PARAMETER_BITCLK_SHIFT); + val |= div << SPFI_DEVICE_PARAMETER_BITCLK_SHIFT; + spfi_writel(spfi, val, SPFI_DEVICE_PARAMETER(spi->chip_select)); + + spfi_writel(spfi, xfer->len << SPFI_TRANSACTION_TSIZE_SHIFT, + SPFI_TRANSACTION); + + val = spfi_readl(spfi, SPFI_CONTROL); + val &= ~(SPFI_CONTROL_SEND_DMA | SPFI_CONTROL_GET_DMA); + if (xfer->tx_buf) + val |= SPFI_CONTROL_SEND_DMA; + if (xfer->rx_buf) + val |= SPFI_CONTROL_GET_DMA; + val &= ~(SPFI_CONTROL_TMODE_MASK << SPFI_CONTROL_TMODE_SHIFT); + if (xfer->tx_nbits == SPI_NBITS_DUAL && + xfer->rx_nbits == SPI_NBITS_DUAL) + val |= SPFI_CONTROL_TMODE_DUAL << SPFI_CONTROL_TMODE_SHIFT; + else if (xfer->tx_nbits == SPI_NBITS_QUAD && + xfer->rx_nbits == SPI_NBITS_QUAD) + val |= SPFI_CONTROL_TMODE_QUAD << SPFI_CONTROL_TMODE_SHIFT; + spfi_writel(spfi, val, SPFI_CONTROL); +} + +static int img_spfi_transfer_one(struct spi_master *master, + struct spi_device *spi, + struct spi_transfer *xfer) +{ + struct img_spfi *spfi = spi_master_get_devdata(spi->master); + int ret; + + if (xfer->len > SPFI_TRANSACTION_TSIZE_MASK) { + dev_err(spfi->dev, + "Transfer length (%d) is greater than the max supported (%d)", + xfer->len, SPFI_TRANSACTION_TSIZE_MASK); + return -EINVAL; + } + + img_spfi_config(master, spi, xfer); + if (master->can_dma && master->can_dma(master, spi, xfer)) + ret = img_spfi_start_dma(master, spi, xfer); + else + ret = img_spfi_start_pio(master, spi, xfer); + + return ret; +} + +static bool img_spfi_can_dma(struct spi_master *master, struct spi_device *spi, + struct spi_transfer *xfer) +{ + if (xfer->len > SPFI_32BIT_FIFO_SIZE) + return true; + return false; +} + +static irqreturn_t img_spfi_irq(int irq, void *dev_id) +{ + struct img_spfi *spfi = (struct img_spfi *)dev_id; + u32 status; + + status = spfi_readl(spfi, SPFI_INTERRUPT_STATUS); + if (status & SPFI_INTERRUPT_IACCESS) { + spfi_writel(spfi, SPFI_INTERRUPT_IACCESS, SPFI_INTERRUPT_CLEAR); + dev_err(spfi->dev, "Illegal access interrupt"); + return IRQ_HANDLED; + } + + return IRQ_NONE; +} + +static int img_spfi_probe(struct platform_device *pdev) +{ + struct spi_master *master; + struct img_spfi *spfi; + struct resource *res; + int ret; + + master = spi_alloc_master(&pdev->dev, sizeof(*spfi)); + if (!master) + return -ENOMEM; + platform_set_drvdata(pdev, master); + + spfi = spi_master_get_devdata(master); + spfi->dev = &pdev->dev; + spfi->master = master; + spin_lock_init(&spfi->lock); + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + spfi->regs = devm_ioremap_resource(spfi->dev, res); + if (IS_ERR(spfi->regs)) { + ret = PTR_ERR(spfi->regs); + goto put_spi; + } + spfi->phys = res->start; + + spfi->irq = platform_get_irq(pdev, 0); + if (spfi->irq < 0) { + ret = spfi->irq; + goto put_spi; + } + ret = devm_request_irq(spfi->dev, spfi->irq, img_spfi_irq, + IRQ_TYPE_LEVEL_HIGH, dev_name(spfi->dev), spfi); + if (ret) + goto put_spi; + + spfi->sys_clk = devm_clk_get(spfi->dev, "sys"); + if (IS_ERR(spfi->sys_clk)) { + ret = PTR_ERR(spfi->sys_clk); + goto put_spi; + } + spfi->spfi_clk = devm_clk_get(spfi->dev, "spfi"); + if (IS_ERR(spfi->spfi_clk)) { + ret = PTR_ERR(spfi->spfi_clk); + goto put_spi; + } + + ret = clk_prepare_enable(spfi->sys_clk); + if (ret) + goto put_spi; + ret = clk_prepare_enable(spfi->spfi_clk); + if (ret) + goto disable_pclk; + + spfi_reset(spfi); + /* + * Only enable the error (IACCESS) interrupt. In PIO mode we'll + * poll the status of the FIFOs. + */ + spfi_writel(spfi, SPFI_INTERRUPT_IACCESS, SPFI_INTERRUPT_ENABLE); + + master->auto_runtime_pm = true; + master->bus_num = pdev->id; + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_TX_DUAL | SPI_RX_DUAL; + if (of_property_read_bool(spfi->dev->of_node, "img,supports-quad-mode")) + master->mode_bits |= SPI_TX_QUAD | SPI_RX_QUAD; + master->dev.of_node = pdev->dev.of_node; + master->bits_per_word_mask = SPI_BPW_MASK(32) | SPI_BPW_MASK(8); + master->max_speed_hz = clk_get_rate(spfi->spfi_clk) / 4; + master->min_speed_hz = clk_get_rate(spfi->spfi_clk) / 512; + + master->setup = img_spfi_setup; + master->cleanup = img_spfi_cleanup; + master->transfer_one = img_spfi_transfer_one; + master->prepare_message = img_spfi_prepare; + master->unprepare_message = img_spfi_unprepare; + master->handle_err = img_spfi_handle_err; + + spfi->tx_ch = dma_request_slave_channel(spfi->dev, "tx"); + spfi->rx_ch = dma_request_slave_channel(spfi->dev, "rx"); + if (!spfi->tx_ch || !spfi->rx_ch) { + if (spfi->tx_ch) + dma_release_channel(spfi->tx_ch); + if (spfi->rx_ch) + dma_release_channel(spfi->rx_ch); + dev_warn(spfi->dev, "Failed to get DMA channels, falling back to PIO mode\n"); + } else { + master->dma_tx = spfi->tx_ch; + master->dma_rx = spfi->rx_ch; + master->can_dma = img_spfi_can_dma; + } + + pm_runtime_set_active(spfi->dev); + pm_runtime_enable(spfi->dev); + + ret = devm_spi_register_master(spfi->dev, master); + if (ret) + goto disable_pm; + + return 0; + +disable_pm: + pm_runtime_disable(spfi->dev); + if (spfi->rx_ch) + dma_release_channel(spfi->rx_ch); + if (spfi->tx_ch) + dma_release_channel(spfi->tx_ch); + clk_disable_unprepare(spfi->spfi_clk); +disable_pclk: + clk_disable_unprepare(spfi->sys_clk); +put_spi: + spi_master_put(master); + + return ret; +} + +static int img_spfi_remove(struct platform_device *pdev) +{ + struct spi_master *master = platform_get_drvdata(pdev); + struct img_spfi *spfi = spi_master_get_devdata(master); + + if (spfi->tx_ch) + dma_release_channel(spfi->tx_ch); + if (spfi->rx_ch) + dma_release_channel(spfi->rx_ch); + + pm_runtime_disable(spfi->dev); + if (!pm_runtime_status_suspended(spfi->dev)) { + clk_disable_unprepare(spfi->spfi_clk); + clk_disable_unprepare(spfi->sys_clk); + } + + spi_master_put(master); + + return 0; +} + +#ifdef CONFIG_PM +static int img_spfi_runtime_suspend(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct img_spfi *spfi = spi_master_get_devdata(master); + + clk_disable_unprepare(spfi->spfi_clk); + clk_disable_unprepare(spfi->sys_clk); + + return 0; +} + +static int img_spfi_runtime_resume(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct img_spfi *spfi = spi_master_get_devdata(master); + int ret; + + ret = clk_prepare_enable(spfi->sys_clk); + if (ret) + return ret; + ret = clk_prepare_enable(spfi->spfi_clk); + if (ret) { + clk_disable_unprepare(spfi->sys_clk); + return ret; + } + + return 0; +} +#endif /* CONFIG_PM */ + +#ifdef CONFIG_PM_SLEEP +static int img_spfi_suspend(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + + return spi_master_suspend(master); +} + +static int img_spfi_resume(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct img_spfi *spfi = spi_master_get_devdata(master); + int ret; + + ret = pm_runtime_get_sync(dev); + if (ret) + return ret; + spfi_reset(spfi); + pm_runtime_put(dev); + + return spi_master_resume(master); +} +#endif /* CONFIG_PM_SLEEP */ + +static const struct dev_pm_ops img_spfi_pm_ops = { + SET_RUNTIME_PM_OPS(img_spfi_runtime_suspend, img_spfi_runtime_resume, + NULL) + SET_SYSTEM_SLEEP_PM_OPS(img_spfi_suspend, img_spfi_resume) +}; + +static const struct of_device_id img_spfi_of_match[] = { + { .compatible = "img,spfi", }, + { }, +}; +MODULE_DEVICE_TABLE(of, img_spfi_of_match); + +static struct platform_driver img_spfi_driver = { + .driver = { + .name = "img-spfi", + .pm = &img_spfi_pm_ops, + .of_match_table = of_match_ptr(img_spfi_of_match), + }, + .probe = img_spfi_probe, + .remove = img_spfi_remove, +}; +module_platform_driver(img_spfi_driver); + +MODULE_DESCRIPTION("IMG SPFI controller driver"); +MODULE_AUTHOR("Andrew Bresticker <abrestic@chromium.org>"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c new file mode 100644 index 000000000..f08e812b2 --- /dev/null +++ b/drivers/spi/spi-imx.c @@ -0,0 +1,1249 @@ +/* + * Copyright 2004-2007 Freescale Semiconductor, Inc. All Rights Reserved. + * Copyright (C) 2008 Juergen Beisert + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the + * Free Software Foundation + * 51 Franklin Street, Fifth Floor + * Boston, MA 02110-1301, USA. + */ + +#include <linux/clk.h> +#include <linux/completion.h> +#include <linux/delay.h> +#include <linux/dmaengine.h> +#include <linux/dma-mapping.h> +#include <linux/err.h> +#include <linux/gpio.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/irq.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/spi/spi.h> +#include <linux/spi/spi_bitbang.h> +#include <linux/types.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/of_gpio.h> + +#include <linux/platform_data/dma-imx.h> +#include <linux/platform_data/spi-imx.h> + +#define DRIVER_NAME "spi_imx" + +#define MXC_CSPIRXDATA 0x00 +#define MXC_CSPITXDATA 0x04 +#define MXC_CSPICTRL 0x08 +#define MXC_CSPIINT 0x0c +#define MXC_RESET 0x1c + +/* generic defines to abstract from the different register layouts */ +#define MXC_INT_RR (1 << 0) /* Receive data ready interrupt */ +#define MXC_INT_TE (1 << 1) /* Transmit FIFO empty interrupt */ + +/* The maximum bytes that a sdma BD can transfer.*/ +#define MAX_SDMA_BD_BYTES (1 << 15) +#define IMX_DMA_TIMEOUT (msecs_to_jiffies(3000)) +struct spi_imx_config { + unsigned int speed_hz; + unsigned int bpw; + unsigned int mode; + u8 cs; +}; + +enum spi_imx_devtype { + IMX1_CSPI, + IMX21_CSPI, + IMX27_CSPI, + IMX31_CSPI, + IMX35_CSPI, /* CSPI on all i.mx except above */ + IMX51_ECSPI, /* ECSPI on i.mx51 and later */ +}; + +struct spi_imx_data; + +struct spi_imx_devtype_data { + void (*intctrl)(struct spi_imx_data *, int); + int (*config)(struct spi_imx_data *, struct spi_imx_config *); + void (*trigger)(struct spi_imx_data *); + int (*rx_available)(struct spi_imx_data *); + void (*reset)(struct spi_imx_data *); + enum spi_imx_devtype devtype; +}; + +struct spi_imx_data { + struct spi_bitbang bitbang; + + struct completion xfer_done; + void __iomem *base; + struct clk *clk_per; + struct clk *clk_ipg; + unsigned long spi_clk; + + unsigned int count; + void (*tx)(struct spi_imx_data *); + void (*rx)(struct spi_imx_data *); + void *rx_buf; + const void *tx_buf; + unsigned int txfifo; /* number of words pushed in tx FIFO */ + + /* DMA */ + unsigned int dma_is_inited; + unsigned int dma_finished; + bool usedma; + u32 rx_wml; + u32 tx_wml; + u32 rxt_wml; + struct completion dma_rx_completion; + struct completion dma_tx_completion; + + const struct spi_imx_devtype_data *devtype_data; + int chipselect[0]; +}; + +static inline int is_imx27_cspi(struct spi_imx_data *d) +{ + return d->devtype_data->devtype == IMX27_CSPI; +} + +static inline int is_imx35_cspi(struct spi_imx_data *d) +{ + return d->devtype_data->devtype == IMX35_CSPI; +} + +static inline unsigned spi_imx_get_fifosize(struct spi_imx_data *d) +{ + return (d->devtype_data->devtype == IMX51_ECSPI) ? 64 : 8; +} + +#define MXC_SPI_BUF_RX(type) \ +static void spi_imx_buf_rx_##type(struct spi_imx_data *spi_imx) \ +{ \ + unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA); \ + \ + if (spi_imx->rx_buf) { \ + *(type *)spi_imx->rx_buf = val; \ + spi_imx->rx_buf += sizeof(type); \ + } \ +} + +#define MXC_SPI_BUF_TX(type) \ +static void spi_imx_buf_tx_##type(struct spi_imx_data *spi_imx) \ +{ \ + type val = 0; \ + \ + if (spi_imx->tx_buf) { \ + val = *(type *)spi_imx->tx_buf; \ + spi_imx->tx_buf += sizeof(type); \ + } \ + \ + spi_imx->count -= sizeof(type); \ + \ + writel(val, spi_imx->base + MXC_CSPITXDATA); \ +} + +MXC_SPI_BUF_RX(u8) +MXC_SPI_BUF_TX(u8) +MXC_SPI_BUF_RX(u16) +MXC_SPI_BUF_TX(u16) +MXC_SPI_BUF_RX(u32) +MXC_SPI_BUF_TX(u32) + +/* First entry is reserved, second entry is valid only if SDHC_SPIEN is set + * (which is currently not the case in this driver) + */ +static int mxc_clkdivs[] = {0, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, 128, 192, + 256, 384, 512, 768, 1024}; + +/* MX21, MX27 */ +static unsigned int spi_imx_clkdiv_1(unsigned int fin, + unsigned int fspi, unsigned int max) +{ + int i; + + for (i = 2; i < max; i++) + if (fspi * mxc_clkdivs[i] >= fin) + return i; + + return max; +} + +/* MX1, MX31, MX35, MX51 CSPI */ +static unsigned int spi_imx_clkdiv_2(unsigned int fin, + unsigned int fspi) +{ + int i, div = 4; + + for (i = 0; i < 7; i++) { + if (fspi * div >= fin) + return i; + div <<= 1; + } + + return 7; +} + +static bool spi_imx_can_dma(struct spi_master *master, struct spi_device *spi, + struct spi_transfer *transfer) +{ + struct spi_imx_data *spi_imx = spi_master_get_devdata(master); + + if (spi_imx->dma_is_inited && (transfer->len > spi_imx->rx_wml) + && (transfer->len > spi_imx->tx_wml)) + return true; + return false; +} + +#define MX51_ECSPI_CTRL 0x08 +#define MX51_ECSPI_CTRL_ENABLE (1 << 0) +#define MX51_ECSPI_CTRL_XCH (1 << 2) +#define MX51_ECSPI_CTRL_SMC (1 << 3) +#define MX51_ECSPI_CTRL_MODE_MASK (0xf << 4) +#define MX51_ECSPI_CTRL_POSTDIV_OFFSET 8 +#define MX51_ECSPI_CTRL_PREDIV_OFFSET 12 +#define MX51_ECSPI_CTRL_CS(cs) ((cs) << 18) +#define MX51_ECSPI_CTRL_BL_OFFSET 20 + +#define MX51_ECSPI_CONFIG 0x0c +#define MX51_ECSPI_CONFIG_SCLKPHA(cs) (1 << ((cs) + 0)) +#define MX51_ECSPI_CONFIG_SCLKPOL(cs) (1 << ((cs) + 4)) +#define MX51_ECSPI_CONFIG_SBBCTRL(cs) (1 << ((cs) + 8)) +#define MX51_ECSPI_CONFIG_SSBPOL(cs) (1 << ((cs) + 12)) +#define MX51_ECSPI_CONFIG_SCLKCTL(cs) (1 << ((cs) + 20)) + +#define MX51_ECSPI_INT 0x10 +#define MX51_ECSPI_INT_TEEN (1 << 0) +#define MX51_ECSPI_INT_RREN (1 << 3) + +#define MX51_ECSPI_DMA 0x14 +#define MX51_ECSPI_DMA_TX_WML_OFFSET 0 +#define MX51_ECSPI_DMA_TX_WML_MASK 0x3F +#define MX51_ECSPI_DMA_RX_WML_OFFSET 16 +#define MX51_ECSPI_DMA_RX_WML_MASK (0x3F << 16) +#define MX51_ECSPI_DMA_RXT_WML_OFFSET 24 +#define MX51_ECSPI_DMA_RXT_WML_MASK (0x3F << 24) + +#define MX51_ECSPI_DMA_TEDEN_OFFSET 7 +#define MX51_ECSPI_DMA_RXDEN_OFFSET 23 +#define MX51_ECSPI_DMA_RXTDEN_OFFSET 31 + +#define MX51_ECSPI_STAT 0x18 +#define MX51_ECSPI_STAT_RR (1 << 3) + +/* MX51 eCSPI */ +static unsigned int mx51_ecspi_clkdiv(unsigned int fin, unsigned int fspi, + unsigned int *fres) +{ + /* + * there are two 4-bit dividers, the pre-divider divides by + * $pre, the post-divider by 2^$post + */ + unsigned int pre, post; + + if (unlikely(fspi > fin)) + return 0; + + post = fls(fin) - fls(fspi); + if (fin > fspi << post) + post++; + + /* now we have: (fin <= fspi << post) with post being minimal */ + + post = max(4U, post) - 4; + if (unlikely(post > 0xf)) { + pr_err("%s: cannot set clock freq: %u (base freq: %u)\n", + __func__, fspi, fin); + return 0xff; + } + + pre = DIV_ROUND_UP(fin, fspi << post) - 1; + + pr_debug("%s: fin: %u, fspi: %u, post: %u, pre: %u\n", + __func__, fin, fspi, post, pre); + + /* Resulting frequency for the SCLK line. */ + *fres = (fin / (pre + 1)) >> post; + + return (pre << MX51_ECSPI_CTRL_PREDIV_OFFSET) | + (post << MX51_ECSPI_CTRL_POSTDIV_OFFSET); +} + +static void __maybe_unused mx51_ecspi_intctrl(struct spi_imx_data *spi_imx, int enable) +{ + unsigned val = 0; + + if (enable & MXC_INT_TE) + val |= MX51_ECSPI_INT_TEEN; + + if (enable & MXC_INT_RR) + val |= MX51_ECSPI_INT_RREN; + + writel(val, spi_imx->base + MX51_ECSPI_INT); +} + +static void __maybe_unused mx51_ecspi_trigger(struct spi_imx_data *spi_imx) +{ + u32 reg = readl(spi_imx->base + MX51_ECSPI_CTRL); + + if (!spi_imx->usedma) + reg |= MX51_ECSPI_CTRL_XCH; + else if (!spi_imx->dma_finished) + reg |= MX51_ECSPI_CTRL_SMC; + else + reg &= ~MX51_ECSPI_CTRL_SMC; + writel(reg, spi_imx->base + MX51_ECSPI_CTRL); +} + +static int __maybe_unused mx51_ecspi_config(struct spi_imx_data *spi_imx, + struct spi_imx_config *config) +{ + u32 ctrl = MX51_ECSPI_CTRL_ENABLE, cfg = 0, dma = 0; + u32 tx_wml_cfg, rx_wml_cfg, rxt_wml_cfg; + u32 clk = config->speed_hz, delay; + + /* + * The hardware seems to have a race condition when changing modes. The + * current assumption is that the selection of the channel arrives + * earlier in the hardware than the mode bits when they are written at + * the same time. + * So set master mode for all channels as we do not support slave mode. + */ + ctrl |= MX51_ECSPI_CTRL_MODE_MASK; + + /* set clock speed */ + ctrl |= mx51_ecspi_clkdiv(spi_imx->spi_clk, config->speed_hz, &clk); + + /* set chip select to use */ + ctrl |= MX51_ECSPI_CTRL_CS(config->cs); + + ctrl |= (config->bpw - 1) << MX51_ECSPI_CTRL_BL_OFFSET; + + cfg |= MX51_ECSPI_CONFIG_SBBCTRL(config->cs); + + if (config->mode & SPI_CPHA) + cfg |= MX51_ECSPI_CONFIG_SCLKPHA(config->cs); + + if (config->mode & SPI_CPOL) { + cfg |= MX51_ECSPI_CONFIG_SCLKPOL(config->cs); + cfg |= MX51_ECSPI_CONFIG_SCLKCTL(config->cs); + } + if (config->mode & SPI_CS_HIGH) + cfg |= MX51_ECSPI_CONFIG_SSBPOL(config->cs); + + writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL); + writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG); + + /* + * Wait until the changes in the configuration register CONFIGREG + * propagate into the hardware. It takes exactly one tick of the + * SCLK clock, but we will wait two SCLK clock just to be sure. The + * effect of the delay it takes for the hardware to apply changes + * is noticable if the SCLK clock run very slow. In such a case, if + * the polarity of SCLK should be inverted, the GPIO ChipSelect might + * be asserted before the SCLK polarity changes, which would disrupt + * the SPI communication as the device on the other end would consider + * the change of SCLK polarity as a clock tick already. + */ + delay = (2 * 1000000) / clk; + if (likely(delay < 10)) /* SCLK is faster than 100 kHz */ + udelay(delay); + else /* SCLK is _very_ slow */ + usleep_range(delay, delay + 10); + + /* + * Configure the DMA register: setup the watermark + * and enable DMA request. + */ + if (spi_imx->dma_is_inited) { + dma = readl(spi_imx->base + MX51_ECSPI_DMA); + + spi_imx->rxt_wml = spi_imx_get_fifosize(spi_imx) / 2; + rx_wml_cfg = spi_imx->rx_wml << MX51_ECSPI_DMA_RX_WML_OFFSET; + tx_wml_cfg = spi_imx->tx_wml << MX51_ECSPI_DMA_TX_WML_OFFSET; + rxt_wml_cfg = spi_imx->rxt_wml << MX51_ECSPI_DMA_RXT_WML_OFFSET; + dma = (dma & ~MX51_ECSPI_DMA_TX_WML_MASK + & ~MX51_ECSPI_DMA_RX_WML_MASK + & ~MX51_ECSPI_DMA_RXT_WML_MASK) + | rx_wml_cfg | tx_wml_cfg | rxt_wml_cfg + |(1 << MX51_ECSPI_DMA_TEDEN_OFFSET) + |(1 << MX51_ECSPI_DMA_RXDEN_OFFSET) + |(1 << MX51_ECSPI_DMA_RXTDEN_OFFSET); + + writel(dma, spi_imx->base + MX51_ECSPI_DMA); + } + + return 0; +} + +static int __maybe_unused mx51_ecspi_rx_available(struct spi_imx_data *spi_imx) +{ + return readl(spi_imx->base + MX51_ECSPI_STAT) & MX51_ECSPI_STAT_RR; +} + +static void __maybe_unused mx51_ecspi_reset(struct spi_imx_data *spi_imx) +{ + /* drain receive buffer */ + while (mx51_ecspi_rx_available(spi_imx)) + readl(spi_imx->base + MXC_CSPIRXDATA); +} + +#define MX31_INTREG_TEEN (1 << 0) +#define MX31_INTREG_RREN (1 << 3) + +#define MX31_CSPICTRL_ENABLE (1 << 0) +#define MX31_CSPICTRL_MASTER (1 << 1) +#define MX31_CSPICTRL_XCH (1 << 2) +#define MX31_CSPICTRL_POL (1 << 4) +#define MX31_CSPICTRL_PHA (1 << 5) +#define MX31_CSPICTRL_SSCTL (1 << 6) +#define MX31_CSPICTRL_SSPOL (1 << 7) +#define MX31_CSPICTRL_BC_SHIFT 8 +#define MX35_CSPICTRL_BL_SHIFT 20 +#define MX31_CSPICTRL_CS_SHIFT 24 +#define MX35_CSPICTRL_CS_SHIFT 12 +#define MX31_CSPICTRL_DR_SHIFT 16 + +#define MX31_CSPISTATUS 0x14 +#define MX31_STATUS_RR (1 << 3) + +/* These functions also work for the i.MX35, but be aware that + * the i.MX35 has a slightly different register layout for bits + * we do not use here. + */ +static void __maybe_unused mx31_intctrl(struct spi_imx_data *spi_imx, int enable) +{ + unsigned int val = 0; + + if (enable & MXC_INT_TE) + val |= MX31_INTREG_TEEN; + if (enable & MXC_INT_RR) + val |= MX31_INTREG_RREN; + + writel(val, spi_imx->base + MXC_CSPIINT); +} + +static void __maybe_unused mx31_trigger(struct spi_imx_data *spi_imx) +{ + unsigned int reg; + + reg = readl(spi_imx->base + MXC_CSPICTRL); + reg |= MX31_CSPICTRL_XCH; + writel(reg, spi_imx->base + MXC_CSPICTRL); +} + +static int __maybe_unused mx31_config(struct spi_imx_data *spi_imx, + struct spi_imx_config *config) +{ + unsigned int reg = MX31_CSPICTRL_ENABLE | MX31_CSPICTRL_MASTER; + int cs = spi_imx->chipselect[config->cs]; + + reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, config->speed_hz) << + MX31_CSPICTRL_DR_SHIFT; + + if (is_imx35_cspi(spi_imx)) { + reg |= (config->bpw - 1) << MX35_CSPICTRL_BL_SHIFT; + reg |= MX31_CSPICTRL_SSCTL; + } else { + reg |= (config->bpw - 1) << MX31_CSPICTRL_BC_SHIFT; + } + + if (config->mode & SPI_CPHA) + reg |= MX31_CSPICTRL_PHA; + if (config->mode & SPI_CPOL) + reg |= MX31_CSPICTRL_POL; + if (config->mode & SPI_CS_HIGH) + reg |= MX31_CSPICTRL_SSPOL; + if (cs < 0) + reg |= (cs + 32) << + (is_imx35_cspi(spi_imx) ? MX35_CSPICTRL_CS_SHIFT : + MX31_CSPICTRL_CS_SHIFT); + + writel(reg, spi_imx->base + MXC_CSPICTRL); + + return 0; +} + +static int __maybe_unused mx31_rx_available(struct spi_imx_data *spi_imx) +{ + return readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR; +} + +static void __maybe_unused mx31_reset(struct spi_imx_data *spi_imx) +{ + /* drain receive buffer */ + while (readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR) + readl(spi_imx->base + MXC_CSPIRXDATA); +} + +#define MX21_INTREG_RR (1 << 4) +#define MX21_INTREG_TEEN (1 << 9) +#define MX21_INTREG_RREN (1 << 13) + +#define MX21_CSPICTRL_POL (1 << 5) +#define MX21_CSPICTRL_PHA (1 << 6) +#define MX21_CSPICTRL_SSPOL (1 << 8) +#define MX21_CSPICTRL_XCH (1 << 9) +#define MX21_CSPICTRL_ENABLE (1 << 10) +#define MX21_CSPICTRL_MASTER (1 << 11) +#define MX21_CSPICTRL_DR_SHIFT 14 +#define MX21_CSPICTRL_CS_SHIFT 19 + +static void __maybe_unused mx21_intctrl(struct spi_imx_data *spi_imx, int enable) +{ + unsigned int val = 0; + + if (enable & MXC_INT_TE) + val |= MX21_INTREG_TEEN; + if (enable & MXC_INT_RR) + val |= MX21_INTREG_RREN; + + writel(val, spi_imx->base + MXC_CSPIINT); +} + +static void __maybe_unused mx21_trigger(struct spi_imx_data *spi_imx) +{ + unsigned int reg; + + reg = readl(spi_imx->base + MXC_CSPICTRL); + reg |= MX21_CSPICTRL_XCH; + writel(reg, spi_imx->base + MXC_CSPICTRL); +} + +static int __maybe_unused mx21_config(struct spi_imx_data *spi_imx, + struct spi_imx_config *config) +{ + unsigned int reg = MX21_CSPICTRL_ENABLE | MX21_CSPICTRL_MASTER; + int cs = spi_imx->chipselect[config->cs]; + unsigned int max = is_imx27_cspi(spi_imx) ? 16 : 18; + + reg |= spi_imx_clkdiv_1(spi_imx->spi_clk, config->speed_hz, max) << + MX21_CSPICTRL_DR_SHIFT; + reg |= config->bpw - 1; + + if (config->mode & SPI_CPHA) + reg |= MX21_CSPICTRL_PHA; + if (config->mode & SPI_CPOL) + reg |= MX21_CSPICTRL_POL; + if (config->mode & SPI_CS_HIGH) + reg |= MX21_CSPICTRL_SSPOL; + if (cs < 0) + reg |= (cs + 32) << MX21_CSPICTRL_CS_SHIFT; + + writel(reg, spi_imx->base + MXC_CSPICTRL); + + return 0; +} + +static int __maybe_unused mx21_rx_available(struct spi_imx_data *spi_imx) +{ + return readl(spi_imx->base + MXC_CSPIINT) & MX21_INTREG_RR; +} + +static void __maybe_unused mx21_reset(struct spi_imx_data *spi_imx) +{ + writel(1, spi_imx->base + MXC_RESET); +} + +#define MX1_INTREG_RR (1 << 3) +#define MX1_INTREG_TEEN (1 << 8) +#define MX1_INTREG_RREN (1 << 11) + +#define MX1_CSPICTRL_POL (1 << 4) +#define MX1_CSPICTRL_PHA (1 << 5) +#define MX1_CSPICTRL_XCH (1 << 8) +#define MX1_CSPICTRL_ENABLE (1 << 9) +#define MX1_CSPICTRL_MASTER (1 << 10) +#define MX1_CSPICTRL_DR_SHIFT 13 + +static void __maybe_unused mx1_intctrl(struct spi_imx_data *spi_imx, int enable) +{ + unsigned int val = 0; + + if (enable & MXC_INT_TE) + val |= MX1_INTREG_TEEN; + if (enable & MXC_INT_RR) + val |= MX1_INTREG_RREN; + + writel(val, spi_imx->base + MXC_CSPIINT); +} + +static void __maybe_unused mx1_trigger(struct spi_imx_data *spi_imx) +{ + unsigned int reg; + + reg = readl(spi_imx->base + MXC_CSPICTRL); + reg |= MX1_CSPICTRL_XCH; + writel(reg, spi_imx->base + MXC_CSPICTRL); +} + +static int __maybe_unused mx1_config(struct spi_imx_data *spi_imx, + struct spi_imx_config *config) +{ + unsigned int reg = MX1_CSPICTRL_ENABLE | MX1_CSPICTRL_MASTER; + + reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, config->speed_hz) << + MX1_CSPICTRL_DR_SHIFT; + reg |= config->bpw - 1; + + if (config->mode & SPI_CPHA) + reg |= MX1_CSPICTRL_PHA; + if (config->mode & SPI_CPOL) + reg |= MX1_CSPICTRL_POL; + + writel(reg, spi_imx->base + MXC_CSPICTRL); + + return 0; +} + +static int __maybe_unused mx1_rx_available(struct spi_imx_data *spi_imx) +{ + return readl(spi_imx->base + MXC_CSPIINT) & MX1_INTREG_RR; +} + +static void __maybe_unused mx1_reset(struct spi_imx_data *spi_imx) +{ + writel(1, spi_imx->base + MXC_RESET); +} + +static struct spi_imx_devtype_data imx1_cspi_devtype_data = { + .intctrl = mx1_intctrl, + .config = mx1_config, + .trigger = mx1_trigger, + .rx_available = mx1_rx_available, + .reset = mx1_reset, + .devtype = IMX1_CSPI, +}; + +static struct spi_imx_devtype_data imx21_cspi_devtype_data = { + .intctrl = mx21_intctrl, + .config = mx21_config, + .trigger = mx21_trigger, + .rx_available = mx21_rx_available, + .reset = mx21_reset, + .devtype = IMX21_CSPI, +}; + +static struct spi_imx_devtype_data imx27_cspi_devtype_data = { + /* i.mx27 cspi shares the functions with i.mx21 one */ + .intctrl = mx21_intctrl, + .config = mx21_config, + .trigger = mx21_trigger, + .rx_available = mx21_rx_available, + .reset = mx21_reset, + .devtype = IMX27_CSPI, +}; + +static struct spi_imx_devtype_data imx31_cspi_devtype_data = { + .intctrl = mx31_intctrl, + .config = mx31_config, + .trigger = mx31_trigger, + .rx_available = mx31_rx_available, + .reset = mx31_reset, + .devtype = IMX31_CSPI, +}; + +static struct spi_imx_devtype_data imx35_cspi_devtype_data = { + /* i.mx35 and later cspi shares the functions with i.mx31 one */ + .intctrl = mx31_intctrl, + .config = mx31_config, + .trigger = mx31_trigger, + .rx_available = mx31_rx_available, + .reset = mx31_reset, + .devtype = IMX35_CSPI, +}; + +static struct spi_imx_devtype_data imx51_ecspi_devtype_data = { + .intctrl = mx51_ecspi_intctrl, + .config = mx51_ecspi_config, + .trigger = mx51_ecspi_trigger, + .rx_available = mx51_ecspi_rx_available, + .reset = mx51_ecspi_reset, + .devtype = IMX51_ECSPI, +}; + +static struct platform_device_id spi_imx_devtype[] = { + { + .name = "imx1-cspi", + .driver_data = (kernel_ulong_t) &imx1_cspi_devtype_data, + }, { + .name = "imx21-cspi", + .driver_data = (kernel_ulong_t) &imx21_cspi_devtype_data, + }, { + .name = "imx27-cspi", + .driver_data = (kernel_ulong_t) &imx27_cspi_devtype_data, + }, { + .name = "imx31-cspi", + .driver_data = (kernel_ulong_t) &imx31_cspi_devtype_data, + }, { + .name = "imx35-cspi", + .driver_data = (kernel_ulong_t) &imx35_cspi_devtype_data, + }, { + .name = "imx51-ecspi", + .driver_data = (kernel_ulong_t) &imx51_ecspi_devtype_data, + }, { + /* sentinel */ + } +}; + +static const struct of_device_id spi_imx_dt_ids[] = { + { .compatible = "fsl,imx1-cspi", .data = &imx1_cspi_devtype_data, }, + { .compatible = "fsl,imx21-cspi", .data = &imx21_cspi_devtype_data, }, + { .compatible = "fsl,imx27-cspi", .data = &imx27_cspi_devtype_data, }, + { .compatible = "fsl,imx31-cspi", .data = &imx31_cspi_devtype_data, }, + { .compatible = "fsl,imx35-cspi", .data = &imx35_cspi_devtype_data, }, + { .compatible = "fsl,imx51-ecspi", .data = &imx51_ecspi_devtype_data, }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, spi_imx_dt_ids); + +static void spi_imx_chipselect(struct spi_device *spi, int is_active) +{ + struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master); + int gpio = spi_imx->chipselect[spi->chip_select]; + int active = is_active != BITBANG_CS_INACTIVE; + int dev_is_lowactive = !(spi->mode & SPI_CS_HIGH); + + if (!gpio_is_valid(gpio)) + return; + + gpio_set_value(gpio, dev_is_lowactive ^ active); +} + +static void spi_imx_push(struct spi_imx_data *spi_imx) +{ + while (spi_imx->txfifo < spi_imx_get_fifosize(spi_imx)) { + if (!spi_imx->count) + break; + spi_imx->tx(spi_imx); + spi_imx->txfifo++; + } + + spi_imx->devtype_data->trigger(spi_imx); +} + +static irqreturn_t spi_imx_isr(int irq, void *dev_id) +{ + struct spi_imx_data *spi_imx = dev_id; + + while (spi_imx->devtype_data->rx_available(spi_imx)) { + spi_imx->rx(spi_imx); + spi_imx->txfifo--; + } + + if (spi_imx->count) { + spi_imx_push(spi_imx); + return IRQ_HANDLED; + } + + if (spi_imx->txfifo) { + /* No data left to push, but still waiting for rx data, + * enable receive data available interrupt. + */ + spi_imx->devtype_data->intctrl( + spi_imx, MXC_INT_RR); + return IRQ_HANDLED; + } + + spi_imx->devtype_data->intctrl(spi_imx, 0); + complete(&spi_imx->xfer_done); + + return IRQ_HANDLED; +} + +static int spi_imx_setupxfer(struct spi_device *spi, + struct spi_transfer *t) +{ + struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master); + struct spi_imx_config config; + + config.bpw = t ? t->bits_per_word : spi->bits_per_word; + config.speed_hz = t ? t->speed_hz : spi->max_speed_hz; + config.mode = spi->mode; + config.cs = spi->chip_select; + + if (!config.speed_hz) + config.speed_hz = spi->max_speed_hz; + if (!config.bpw) + config.bpw = spi->bits_per_word; + + /* Initialize the functions for transfer */ + if (config.bpw <= 8) { + spi_imx->rx = spi_imx_buf_rx_u8; + spi_imx->tx = spi_imx_buf_tx_u8; + } else if (config.bpw <= 16) { + spi_imx->rx = spi_imx_buf_rx_u16; + spi_imx->tx = spi_imx_buf_tx_u16; + } else { + spi_imx->rx = spi_imx_buf_rx_u32; + spi_imx->tx = spi_imx_buf_tx_u32; + } + + spi_imx->devtype_data->config(spi_imx, &config); + + return 0; +} + +static void spi_imx_sdma_exit(struct spi_imx_data *spi_imx) +{ + struct spi_master *master = spi_imx->bitbang.master; + + if (master->dma_rx) { + dma_release_channel(master->dma_rx); + master->dma_rx = NULL; + } + + if (master->dma_tx) { + dma_release_channel(master->dma_tx); + master->dma_tx = NULL; + } + + spi_imx->dma_is_inited = 0; +} + +static int spi_imx_sdma_init(struct device *dev, struct spi_imx_data *spi_imx, + struct spi_master *master, + const struct resource *res) +{ + struct dma_slave_config slave_config = {}; + int ret; + + /* use pio mode for i.mx6dl chip TKT238285 */ + if (of_machine_is_compatible("fsl,imx6dl")) + return 0; + + /* Prepare for TX DMA: */ + master->dma_tx = dma_request_slave_channel(dev, "tx"); + if (!master->dma_tx) { + dev_err(dev, "cannot get the TX DMA channel!\n"); + ret = -EINVAL; + goto err; + } + + slave_config.direction = DMA_MEM_TO_DEV; + slave_config.dst_addr = res->start + MXC_CSPITXDATA; + slave_config.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; + slave_config.dst_maxburst = spi_imx_get_fifosize(spi_imx) / 2; + ret = dmaengine_slave_config(master->dma_tx, &slave_config); + if (ret) { + dev_err(dev, "error in TX dma configuration.\n"); + goto err; + } + + /* Prepare for RX : */ + master->dma_rx = dma_request_slave_channel(dev, "rx"); + if (!master->dma_rx) { + dev_dbg(dev, "cannot get the DMA channel.\n"); + ret = -EINVAL; + goto err; + } + + slave_config.direction = DMA_DEV_TO_MEM; + slave_config.src_addr = res->start + MXC_CSPIRXDATA; + slave_config.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; + slave_config.src_maxburst = spi_imx_get_fifosize(spi_imx) / 2; + ret = dmaengine_slave_config(master->dma_rx, &slave_config); + if (ret) { + dev_err(dev, "error in RX dma configuration.\n"); + goto err; + } + + init_completion(&spi_imx->dma_rx_completion); + init_completion(&spi_imx->dma_tx_completion); + master->can_dma = spi_imx_can_dma; + master->max_dma_len = MAX_SDMA_BD_BYTES; + spi_imx->bitbang.master->flags = SPI_MASTER_MUST_RX | + SPI_MASTER_MUST_TX; + spi_imx->tx_wml = spi_imx_get_fifosize(spi_imx) / 2; + spi_imx->rx_wml = spi_imx_get_fifosize(spi_imx) / 2; + spi_imx->dma_is_inited = 1; + + return 0; +err: + spi_imx_sdma_exit(spi_imx); + return ret; +} + +static void spi_imx_dma_rx_callback(void *cookie) +{ + struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie; + + complete(&spi_imx->dma_rx_completion); +} + +static void spi_imx_dma_tx_callback(void *cookie) +{ + struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie; + + complete(&spi_imx->dma_tx_completion); +} + +static int spi_imx_dma_transfer(struct spi_imx_data *spi_imx, + struct spi_transfer *transfer) +{ + struct dma_async_tx_descriptor *desc_tx = NULL, *desc_rx = NULL; + int ret; + unsigned long timeout; + u32 dma; + int left; + struct spi_master *master = spi_imx->bitbang.master; + struct sg_table *tx = &transfer->tx_sg, *rx = &transfer->rx_sg; + + if (tx) { + desc_tx = dmaengine_prep_slave_sg(master->dma_tx, + tx->sgl, tx->nents, DMA_MEM_TO_DEV, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + if (!desc_tx) + goto no_dma; + + desc_tx->callback = spi_imx_dma_tx_callback; + desc_tx->callback_param = (void *)spi_imx; + dmaengine_submit(desc_tx); + } + + if (rx) { + desc_rx = dmaengine_prep_slave_sg(master->dma_rx, + rx->sgl, rx->nents, DMA_DEV_TO_MEM, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + if (!desc_rx) + goto no_dma; + + desc_rx->callback = spi_imx_dma_rx_callback; + desc_rx->callback_param = (void *)spi_imx; + dmaengine_submit(desc_rx); + } + + reinit_completion(&spi_imx->dma_rx_completion); + reinit_completion(&spi_imx->dma_tx_completion); + + /* Trigger the cspi module. */ + spi_imx->dma_finished = 0; + + dma = readl(spi_imx->base + MX51_ECSPI_DMA); + dma = dma & (~MX51_ECSPI_DMA_RXT_WML_MASK); + /* Change RX_DMA_LENGTH trigger dma fetch tail data */ + left = transfer->len % spi_imx->rxt_wml; + if (left) + writel(dma | (left << MX51_ECSPI_DMA_RXT_WML_OFFSET), + spi_imx->base + MX51_ECSPI_DMA); + spi_imx->devtype_data->trigger(spi_imx); + + dma_async_issue_pending(master->dma_tx); + dma_async_issue_pending(master->dma_rx); + /* Wait SDMA to finish the data transfer.*/ + timeout = wait_for_completion_timeout(&spi_imx->dma_tx_completion, + IMX_DMA_TIMEOUT); + if (!timeout) { + pr_warn("%s %s: I/O Error in DMA TX\n", + dev_driver_string(&master->dev), + dev_name(&master->dev)); + dmaengine_terminate_all(master->dma_tx); + } else { + timeout = wait_for_completion_timeout( + &spi_imx->dma_rx_completion, IMX_DMA_TIMEOUT); + if (!timeout) { + pr_warn("%s %s: I/O Error in DMA RX\n", + dev_driver_string(&master->dev), + dev_name(&master->dev)); + spi_imx->devtype_data->reset(spi_imx); + dmaengine_terminate_all(master->dma_rx); + } + writel(dma | + spi_imx->rxt_wml << MX51_ECSPI_DMA_RXT_WML_OFFSET, + spi_imx->base + MX51_ECSPI_DMA); + } + + spi_imx->dma_finished = 1; + spi_imx->devtype_data->trigger(spi_imx); + + if (!timeout) + ret = -ETIMEDOUT; + else + ret = transfer->len; + + return ret; + +no_dma: + pr_warn_once("%s %s: DMA not available, falling back to PIO\n", + dev_driver_string(&master->dev), + dev_name(&master->dev)); + return -EAGAIN; +} + +static int spi_imx_pio_transfer(struct spi_device *spi, + struct spi_transfer *transfer) +{ + struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master); + + spi_imx->tx_buf = transfer->tx_buf; + spi_imx->rx_buf = transfer->rx_buf; + spi_imx->count = transfer->len; + spi_imx->txfifo = 0; + + reinit_completion(&spi_imx->xfer_done); + + spi_imx_push(spi_imx); + + spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE); + + wait_for_completion(&spi_imx->xfer_done); + + return transfer->len; +} + +static int spi_imx_transfer(struct spi_device *spi, + struct spi_transfer *transfer) +{ + int ret; + struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master); + + if (spi_imx->bitbang.master->can_dma && + spi_imx_can_dma(spi_imx->bitbang.master, spi, transfer)) { + spi_imx->usedma = true; + ret = spi_imx_dma_transfer(spi_imx, transfer); + if (ret != -EAGAIN) + return ret; + } + spi_imx->usedma = false; + + return spi_imx_pio_transfer(spi, transfer); +} + +static int spi_imx_setup(struct spi_device *spi) +{ + struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master); + int gpio = spi_imx->chipselect[spi->chip_select]; + + dev_dbg(&spi->dev, "%s: mode %d, %u bpw, %d hz\n", __func__, + spi->mode, spi->bits_per_word, spi->max_speed_hz); + + if (gpio_is_valid(gpio)) + gpio_direction_output(gpio, spi->mode & SPI_CS_HIGH ? 0 : 1); + + spi_imx_chipselect(spi, BITBANG_CS_INACTIVE); + + return 0; +} + +static void spi_imx_cleanup(struct spi_device *spi) +{ +} + +static int +spi_imx_prepare_message(struct spi_master *master, struct spi_message *msg) +{ + struct spi_imx_data *spi_imx = spi_master_get_devdata(master); + int ret; + + ret = clk_enable(spi_imx->clk_per); + if (ret) + return ret; + + ret = clk_enable(spi_imx->clk_ipg); + if (ret) { + clk_disable(spi_imx->clk_per); + return ret; + } + + return 0; +} + +static int +spi_imx_unprepare_message(struct spi_master *master, struct spi_message *msg) +{ + struct spi_imx_data *spi_imx = spi_master_get_devdata(master); + + clk_disable(spi_imx->clk_ipg); + clk_disable(spi_imx->clk_per); + return 0; +} + +static int spi_imx_probe(struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + const struct of_device_id *of_id = + of_match_device(spi_imx_dt_ids, &pdev->dev); + struct spi_imx_master *mxc_platform_info = + dev_get_platdata(&pdev->dev); + struct spi_master *master; + struct spi_imx_data *spi_imx; + struct resource *res; + int i, ret, num_cs, irq; + + if (!np && !mxc_platform_info) { + dev_err(&pdev->dev, "can't get the platform data\n"); + return -EINVAL; + } + + ret = of_property_read_u32(np, "fsl,spi-num-chipselects", &num_cs); + if (ret < 0) { + if (mxc_platform_info) + num_cs = mxc_platform_info->num_chipselect; + else + return ret; + } + + master = spi_alloc_master(&pdev->dev, + sizeof(struct spi_imx_data) + sizeof(int) * num_cs); + if (!master) + return -ENOMEM; + + platform_set_drvdata(pdev, master); + + master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32); + master->bus_num = pdev->id; + master->num_chipselect = num_cs; + + spi_imx = spi_master_get_devdata(master); + spi_imx->bitbang.master = master; + + for (i = 0; i < master->num_chipselect; i++) { + int cs_gpio = of_get_named_gpio(np, "cs-gpios", i); + if (!gpio_is_valid(cs_gpio) && mxc_platform_info) + cs_gpio = mxc_platform_info->chipselect[i]; + + spi_imx->chipselect[i] = cs_gpio; + if (!gpio_is_valid(cs_gpio)) + continue; + + ret = devm_gpio_request(&pdev->dev, spi_imx->chipselect[i], + DRIVER_NAME); + if (ret) { + dev_err(&pdev->dev, "can't get cs gpios\n"); + goto out_master_put; + } + } + + spi_imx->bitbang.chipselect = spi_imx_chipselect; + spi_imx->bitbang.setup_transfer = spi_imx_setupxfer; + spi_imx->bitbang.txrx_bufs = spi_imx_transfer; + spi_imx->bitbang.master->setup = spi_imx_setup; + spi_imx->bitbang.master->cleanup = spi_imx_cleanup; + spi_imx->bitbang.master->prepare_message = spi_imx_prepare_message; + spi_imx->bitbang.master->unprepare_message = spi_imx_unprepare_message; + spi_imx->bitbang.master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH; + + init_completion(&spi_imx->xfer_done); + + spi_imx->devtype_data = of_id ? of_id->data : + (struct spi_imx_devtype_data *) pdev->id_entry->driver_data; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + spi_imx->base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(spi_imx->base)) { + ret = PTR_ERR(spi_imx->base); + goto out_master_put; + } + + irq = platform_get_irq(pdev, 0); + if (irq < 0) { + ret = irq; + goto out_master_put; + } + + ret = devm_request_irq(&pdev->dev, irq, spi_imx_isr, 0, + dev_name(&pdev->dev), spi_imx); + if (ret) { + dev_err(&pdev->dev, "can't get irq%d: %d\n", irq, ret); + goto out_master_put; + } + + spi_imx->clk_ipg = devm_clk_get(&pdev->dev, "ipg"); + if (IS_ERR(spi_imx->clk_ipg)) { + ret = PTR_ERR(spi_imx->clk_ipg); + goto out_master_put; + } + + spi_imx->clk_per = devm_clk_get(&pdev->dev, "per"); + if (IS_ERR(spi_imx->clk_per)) { + ret = PTR_ERR(spi_imx->clk_per); + goto out_master_put; + } + + ret = clk_prepare_enable(spi_imx->clk_per); + if (ret) + goto out_master_put; + + ret = clk_prepare_enable(spi_imx->clk_ipg); + if (ret) + goto out_put_per; + + spi_imx->spi_clk = clk_get_rate(spi_imx->clk_per); + /* + * Only validated on i.mx6 now, can remove the constrain if validated on + * other chips. + */ + if (spi_imx->devtype_data == &imx51_ecspi_devtype_data + && spi_imx_sdma_init(&pdev->dev, spi_imx, master, res)) + dev_err(&pdev->dev, "dma setup error,use pio instead\n"); + + spi_imx->devtype_data->reset(spi_imx); + + spi_imx->devtype_data->intctrl(spi_imx, 0); + + master->dev.of_node = pdev->dev.of_node; + ret = spi_bitbang_start(&spi_imx->bitbang); + if (ret) { + dev_err(&pdev->dev, "bitbang start failed with %d\n", ret); + goto out_clk_put; + } + + dev_info(&pdev->dev, "probed\n"); + + clk_disable(spi_imx->clk_ipg); + clk_disable(spi_imx->clk_per); + return ret; + +out_clk_put: + clk_disable_unprepare(spi_imx->clk_ipg); +out_put_per: + clk_disable_unprepare(spi_imx->clk_per); +out_master_put: + spi_master_put(master); + + return ret; +} + +static int spi_imx_remove(struct platform_device *pdev) +{ + struct spi_master *master = platform_get_drvdata(pdev); + struct spi_imx_data *spi_imx = spi_master_get_devdata(master); + + spi_bitbang_stop(&spi_imx->bitbang); + + writel(0, spi_imx->base + MXC_CSPICTRL); + clk_unprepare(spi_imx->clk_ipg); + clk_unprepare(spi_imx->clk_per); + spi_imx_sdma_exit(spi_imx); + spi_master_put(master); + + return 0; +} + +static struct platform_driver spi_imx_driver = { + .driver = { + .name = DRIVER_NAME, + .of_match_table = spi_imx_dt_ids, + }, + .id_table = spi_imx_devtype, + .probe = spi_imx_probe, + .remove = spi_imx_remove, +}; +module_platform_driver(spi_imx_driver); + +MODULE_DESCRIPTION("SPI Master Controller driver"); +MODULE_AUTHOR("Sascha Hauer, Pengutronix"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:" DRIVER_NAME); diff --git a/drivers/spi/spi-lm70llp.c b/drivers/spi/spi-lm70llp.c new file mode 100644 index 000000000..ba72347cb --- /dev/null +++ b/drivers/spi/spi-lm70llp.c @@ -0,0 +1,344 @@ +/* + * Driver for LM70EVAL-LLP board for the LM70 sensor + * + * Copyright (C) 2006 Kaiwan N Billimoria <kaiwan@designergraphix.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/init.h> +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/parport.h> +#include <linux/sysfs.h> +#include <linux/workqueue.h> + + +#include <linux/spi/spi.h> +#include <linux/spi/spi_bitbang.h> + + +/* + * The LM70 communicates with a host processor using a 3-wire variant of + * the SPI/Microwire bus interface. This driver specifically supports an + * NS LM70 LLP Evaluation Board, interfacing to a PC using its parallel + * port to bitbang an SPI-parport bridge. Accordingly, this is an SPI + * master controller driver. The hwmon/lm70 driver is a "SPI protocol + * driver", layered on top of this one and usable without the lm70llp. + * + * Datasheet and Schematic: + * The LM70 is a temperature sensor chip from National Semiconductor; its + * datasheet is available at http://www.national.com/pf/LM/LM70.html + * The schematic for this particular board (the LM70EVAL-LLP) is + * available (on page 4) here: + * http://www.national.com/appinfo/tempsensors/files/LM70LLPEVALmanual.pdf + * + * Also see Documentation/spi/spi-lm70llp. The SPI<->parport code here is + * (heavily) based on spi-butterfly by David Brownell. + * + * The LM70 LLP connects to the PC parallel port in the following manner: + * + * Parallel LM70 LLP + * Port Direction JP2 Header + * ----------- --------- ------------ + * D0 2 - - + * D1 3 --> V+ 5 + * D2 4 --> V+ 5 + * D3 5 --> V+ 5 + * D4 6 --> V+ 5 + * D5 7 --> nCS 8 + * D6 8 --> SCLK 3 + * D7 9 --> SI/O 5 + * GND 25 - GND 7 + * Select 13 <-- SI/O 1 + * + * Note that parport pin 13 actually gets inverted by the transistor + * arrangement which lets either the parport or the LM70 drive the + * SI/SO signal (see the schematic for details). + */ + +#define DRVNAME "spi-lm70llp" + +#define lm70_INIT 0xBE +#define SIO 0x10 +#define nCS 0x20 +#define SCLK 0x40 + +/*-------------------------------------------------------------------------*/ + +struct spi_lm70llp { + struct spi_bitbang bitbang; + struct parport *port; + struct pardevice *pd; + struct spi_device *spidev_lm70; + struct spi_board_info info; + //struct device *dev; +}; + +/* REVISIT : ugly global ; provides "exclusive open" facility */ +static struct spi_lm70llp *lm70llp; + + +/*-------------------------------------------------------------------*/ + +static inline struct spi_lm70llp *spidev_to_pp(struct spi_device *spi) +{ + return spi->controller_data; +} + +/*---------------------- LM70 LLP eval board-specific inlines follow */ + +/* NOTE: we don't actually need to reread the output values, since they'll + * still be what we wrote before. Plus, going through parport builds in + * a ~1ms/operation delay; these SPI transfers could easily be faster. + */ + +static inline void deassertCS(struct spi_lm70llp *pp) +{ + u8 data = parport_read_data(pp->port); + + data &= ~0x80; /* pull D7/SI-out low while de-asserted */ + parport_write_data(pp->port, data | nCS); +} + +static inline void assertCS(struct spi_lm70llp *pp) +{ + u8 data = parport_read_data(pp->port); + + data |= 0x80; /* pull D7/SI-out high so lm70 drives SO-in */ + parport_write_data(pp->port, data & ~nCS); +} + +static inline void clkHigh(struct spi_lm70llp *pp) +{ + u8 data = parport_read_data(pp->port); + parport_write_data(pp->port, data | SCLK); +} + +static inline void clkLow(struct spi_lm70llp *pp) +{ + u8 data = parport_read_data(pp->port); + parport_write_data(pp->port, data & ~SCLK); +} + +/*------------------------- SPI-LM70-specific inlines ----------------------*/ + +static inline void spidelay(unsigned d) +{ + udelay(d); +} + +static inline void setsck(struct spi_device *s, int is_on) +{ + struct spi_lm70llp *pp = spidev_to_pp(s); + + if (is_on) + clkHigh(pp); + else + clkLow(pp); +} + +static inline void setmosi(struct spi_device *s, int is_on) +{ + /* FIXME update D7 ... this way we can put the chip + * into shutdown mode and read the manufacturer ID, + * but we can't put it back into operational mode. + */ +} + +/* + * getmiso: + * Why do we return 0 when the SIO line is high and vice-versa? + * The fact is, the lm70 eval board from NS (which this driver drives), + * is wired in just such a way : when the lm70's SIO goes high, a transistor + * switches it to low reflecting this on the parport (pin 13), and vice-versa. + */ +static inline int getmiso(struct spi_device *s) +{ + struct spi_lm70llp *pp = spidev_to_pp(s); + return ((SIO == (parport_read_status(pp->port) & SIO)) ? 0 : 1 ); +} +/*--------------------------------------------------------------------*/ + +#include "spi-bitbang-txrx.h" + +static void lm70_chipselect(struct spi_device *spi, int value) +{ + struct spi_lm70llp *pp = spidev_to_pp(spi); + + if (value) + assertCS(pp); + else + deassertCS(pp); +} + +/* + * Our actual bitbanger routine. + */ +static u32 lm70_txrx(struct spi_device *spi, unsigned nsecs, u32 word, u8 bits) +{ + return bitbang_txrx_be_cpha0(spi, nsecs, 0, 0, word, bits); +} + +static void spi_lm70llp_attach(struct parport *p) +{ + struct pardevice *pd; + struct spi_lm70llp *pp; + struct spi_master *master; + int status; + + if (lm70llp) { + printk(KERN_WARNING + "%s: spi_lm70llp instance already loaded. Aborting.\n", + DRVNAME); + return; + } + + /* TODO: this just _assumes_ a lm70 is there ... no probe; + * the lm70 driver could verify it, reading the manf ID. + */ + + master = spi_alloc_master(p->physport->dev, sizeof *pp); + if (!master) { + status = -ENOMEM; + goto out_fail; + } + pp = spi_master_get_devdata(master); + + /* + * SPI and bitbang hookup. + */ + pp->bitbang.master = master; + pp->bitbang.chipselect = lm70_chipselect; + pp->bitbang.txrx_word[SPI_MODE_0] = lm70_txrx; + pp->bitbang.flags = SPI_3WIRE; + + /* + * Parport hookup + */ + pp->port = p; + pd = parport_register_device(p, DRVNAME, + NULL, NULL, NULL, + PARPORT_FLAG_EXCL, pp); + if (!pd) { + status = -ENOMEM; + goto out_free_master; + } + pp->pd = pd; + + status = parport_claim(pd); + if (status < 0) + goto out_parport_unreg; + + /* + * Start SPI ... + */ + status = spi_bitbang_start(&pp->bitbang); + if (status < 0) { + printk(KERN_WARNING + "%s: spi_bitbang_start failed with status %d\n", + DRVNAME, status); + goto out_off_and_release; + } + + /* + * The modalias name MUST match the device_driver name + * for the bus glue code to match and subsequently bind them. + * We are binding to the generic drivers/hwmon/lm70.c device + * driver. + */ + strcpy(pp->info.modalias, "lm70"); + pp->info.max_speed_hz = 6 * 1000 * 1000; + pp->info.chip_select = 0; + pp->info.mode = SPI_3WIRE | SPI_MODE_0; + + /* power up the chip, and let the LM70 control SI/SO */ + parport_write_data(pp->port, lm70_INIT); + + /* Enable access to our primary data structure via + * the board info's (void *)controller_data. + */ + pp->info.controller_data = pp; + pp->spidev_lm70 = spi_new_device(pp->bitbang.master, &pp->info); + if (pp->spidev_lm70) + dev_dbg(&pp->spidev_lm70->dev, "spidev_lm70 at %s\n", + dev_name(&pp->spidev_lm70->dev)); + else { + printk(KERN_WARNING "%s: spi_new_device failed\n", DRVNAME); + status = -ENODEV; + goto out_bitbang_stop; + } + pp->spidev_lm70->bits_per_word = 8; + + lm70llp = pp; + return; + +out_bitbang_stop: + spi_bitbang_stop(&pp->bitbang); +out_off_and_release: + /* power down */ + parport_write_data(pp->port, 0); + mdelay(10); + parport_release(pp->pd); +out_parport_unreg: + parport_unregister_device(pd); +out_free_master: + (void) spi_master_put(master); +out_fail: + pr_info("%s: spi_lm70llp probe fail, status %d\n", DRVNAME, status); +} + +static void spi_lm70llp_detach(struct parport *p) +{ + struct spi_lm70llp *pp; + + if (!lm70llp || lm70llp->port != p) + return; + + pp = lm70llp; + spi_bitbang_stop(&pp->bitbang); + + /* power down */ + parport_write_data(pp->port, 0); + + parport_release(pp->pd); + parport_unregister_device(pp->pd); + + (void) spi_master_put(pp->bitbang.master); + + lm70llp = NULL; +} + + +static struct parport_driver spi_lm70llp_drv = { + .name = DRVNAME, + .attach = spi_lm70llp_attach, + .detach = spi_lm70llp_detach, +}; + +static int __init init_spi_lm70llp(void) +{ + return parport_register_driver(&spi_lm70llp_drv); +} +module_init(init_spi_lm70llp); + +static void __exit cleanup_spi_lm70llp(void) +{ + parport_unregister_driver(&spi_lm70llp_drv); +} +module_exit(cleanup_spi_lm70llp); + +MODULE_AUTHOR("Kaiwan N Billimoria <kaiwan@designergraphix.com>"); +MODULE_DESCRIPTION( + "Parport adapter for the National Semiconductor LM70 LLP eval board"); +MODULE_LICENSE("GPL"); diff --git a/drivers/spi/spi-meson-spifc.c b/drivers/spi/spi-meson-spifc.c new file mode 100644 index 000000000..5468fc70d --- /dev/null +++ b/drivers/spi/spi-meson-spifc.c @@ -0,0 +1,462 @@ +/* + * Driver for Amlogic Meson SPI flash controller (SPIFC) + * + * Copyright (C) 2014 Beniamino Galvani <b.galvani@gmail.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * version 2 as published by the Free Software Foundation. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/regmap.h> +#include <linux/spi/spi.h> +#include <linux/types.h> + +/* register map */ +#define REG_CMD 0x00 +#define REG_ADDR 0x04 +#define REG_CTRL 0x08 +#define REG_CTRL1 0x0c +#define REG_STATUS 0x10 +#define REG_CTRL2 0x14 +#define REG_CLOCK 0x18 +#define REG_USER 0x1c +#define REG_USER1 0x20 +#define REG_USER2 0x24 +#define REG_USER3 0x28 +#define REG_USER4 0x2c +#define REG_SLAVE 0x30 +#define REG_SLAVE1 0x34 +#define REG_SLAVE2 0x38 +#define REG_SLAVE3 0x3c +#define REG_C0 0x40 +#define REG_B8 0x60 +#define REG_MAX 0x7c + +/* register fields */ +#define CMD_USER BIT(18) +#define CTRL_ENABLE_AHB BIT(17) +#define CLOCK_SOURCE BIT(31) +#define CLOCK_DIV_SHIFT 12 +#define CLOCK_DIV_MASK (0x3f << CLOCK_DIV_SHIFT) +#define CLOCK_CNT_HIGH_SHIFT 6 +#define CLOCK_CNT_HIGH_MASK (0x3f << CLOCK_CNT_HIGH_SHIFT) +#define CLOCK_CNT_LOW_SHIFT 0 +#define CLOCK_CNT_LOW_MASK (0x3f << CLOCK_CNT_LOW_SHIFT) +#define USER_DIN_EN_MS BIT(0) +#define USER_CMP_MODE BIT(2) +#define USER_UC_DOUT_SEL BIT(27) +#define USER_UC_DIN_SEL BIT(28) +#define USER_UC_MASK ((BIT(5) - 1) << 27) +#define USER1_BN_UC_DOUT_SHIFT 17 +#define USER1_BN_UC_DOUT_MASK (0xff << 16) +#define USER1_BN_UC_DIN_SHIFT 8 +#define USER1_BN_UC_DIN_MASK (0xff << 8) +#define USER4_CS_ACT BIT(30) +#define SLAVE_TRST_DONE BIT(4) +#define SLAVE_OP_MODE BIT(30) +#define SLAVE_SW_RST BIT(31) + +#define SPIFC_BUFFER_SIZE 64 + +/** + * struct meson_spifc + * @master: the SPI master + * @regmap: regmap for device registers + * @clk: input clock of the built-in baud rate generator + * @device: the device structure + */ +struct meson_spifc { + struct spi_master *master; + struct regmap *regmap; + struct clk *clk; + struct device *dev; +}; + +static const struct regmap_config spifc_regmap_config = { + .reg_bits = 32, + .val_bits = 32, + .reg_stride = 4, + .max_register = REG_MAX, +}; + +/** + * meson_spifc_wait_ready() - wait for the current operation to terminate + * @spifc: the Meson SPI device + * Return: 0 on success, a negative value on error + */ +static int meson_spifc_wait_ready(struct meson_spifc *spifc) +{ + unsigned long deadline = jiffies + msecs_to_jiffies(5); + u32 data; + + do { + regmap_read(spifc->regmap, REG_SLAVE, &data); + if (data & SLAVE_TRST_DONE) + return 0; + cond_resched(); + } while (!time_after(jiffies, deadline)); + + return -ETIMEDOUT; +} + +/** + * meson_spifc_drain_buffer() - copy data from device buffer to memory + * @spifc: the Meson SPI device + * @buf: the destination buffer + * @len: number of bytes to copy + */ +static void meson_spifc_drain_buffer(struct meson_spifc *spifc, u8 *buf, + int len) +{ + u32 data; + int i = 0; + + while (i < len) { + regmap_read(spifc->regmap, REG_C0 + i, &data); + + if (len - i >= 4) { + *((u32 *)buf) = data; + buf += 4; + } else { + memcpy(buf, &data, len - i); + break; + } + i += 4; + } +} + +/** + * meson_spifc_fill_buffer() - copy data from memory to device buffer + * @spifc: the Meson SPI device + * @buf: the source buffer + * @len: number of bytes to copy + */ +static void meson_spifc_fill_buffer(struct meson_spifc *spifc, const u8 *buf, + int len) +{ + u32 data; + int i = 0; + + while (i < len) { + if (len - i >= 4) + data = *(u32 *)buf; + else + memcpy(&data, buf, len - i); + + regmap_write(spifc->regmap, REG_C0 + i, data); + + buf += 4; + i += 4; + } +} + +/** + * meson_spifc_setup_speed() - program the clock divider + * @spifc: the Meson SPI device + * @speed: desired speed in Hz + */ +static void meson_spifc_setup_speed(struct meson_spifc *spifc, u32 speed) +{ + unsigned long parent, value; + int n; + + parent = clk_get_rate(spifc->clk); + n = max_t(int, parent / speed - 1, 1); + + dev_dbg(spifc->dev, "parent %lu, speed %u, n %d\n", parent, + speed, n); + + value = (n << CLOCK_DIV_SHIFT) & CLOCK_DIV_MASK; + value |= (n << CLOCK_CNT_LOW_SHIFT) & CLOCK_CNT_LOW_MASK; + value |= (((n + 1) / 2 - 1) << CLOCK_CNT_HIGH_SHIFT) & + CLOCK_CNT_HIGH_MASK; + + regmap_write(spifc->regmap, REG_CLOCK, value); +} + +/** + * meson_spifc_txrx() - transfer a chunk of data + * @spifc: the Meson SPI device + * @xfer: the current SPI transfer + * @offset: offset of the data to transfer + * @len: length of the data to transfer + * @last_xfer: whether this is the last transfer of the message + * @last_chunk: whether this is the last chunk of the transfer + * Return: 0 on success, a negative value on error + */ +static int meson_spifc_txrx(struct meson_spifc *spifc, + struct spi_transfer *xfer, + int offset, int len, bool last_xfer, + bool last_chunk) +{ + bool keep_cs = true; + int ret; + + if (xfer->tx_buf) + meson_spifc_fill_buffer(spifc, xfer->tx_buf + offset, len); + + /* enable DOUT stage */ + regmap_update_bits(spifc->regmap, REG_USER, USER_UC_MASK, + USER_UC_DOUT_SEL); + regmap_write(spifc->regmap, REG_USER1, + (8 * len - 1) << USER1_BN_UC_DOUT_SHIFT); + + /* enable data input during DOUT */ + regmap_update_bits(spifc->regmap, REG_USER, USER_DIN_EN_MS, + USER_DIN_EN_MS); + + if (last_chunk) { + if (last_xfer) + keep_cs = xfer->cs_change; + else + keep_cs = !xfer->cs_change; + } + + regmap_update_bits(spifc->regmap, REG_USER4, USER4_CS_ACT, + keep_cs ? USER4_CS_ACT : 0); + + /* clear transition done bit */ + regmap_update_bits(spifc->regmap, REG_SLAVE, SLAVE_TRST_DONE, 0); + /* start transfer */ + regmap_update_bits(spifc->regmap, REG_CMD, CMD_USER, CMD_USER); + + ret = meson_spifc_wait_ready(spifc); + + if (!ret && xfer->rx_buf) + meson_spifc_drain_buffer(spifc, xfer->rx_buf + offset, len); + + return ret; +} + +/** + * meson_spifc_transfer_one() - perform a single transfer + * @master: the SPI master + * @spi: the SPI device + * @xfer: the current SPI transfer + * Return: 0 on success, a negative value on error + */ +static int meson_spifc_transfer_one(struct spi_master *master, + struct spi_device *spi, + struct spi_transfer *xfer) +{ + struct meson_spifc *spifc = spi_master_get_devdata(master); + int len, done = 0, ret = 0; + + meson_spifc_setup_speed(spifc, xfer->speed_hz); + + regmap_update_bits(spifc->regmap, REG_CTRL, CTRL_ENABLE_AHB, 0); + + while (done < xfer->len && !ret) { + len = min_t(int, xfer->len - done, SPIFC_BUFFER_SIZE); + ret = meson_spifc_txrx(spifc, xfer, done, len, + spi_transfer_is_last(master, xfer), + done + len >= xfer->len); + done += len; + } + + regmap_update_bits(spifc->regmap, REG_CTRL, CTRL_ENABLE_AHB, + CTRL_ENABLE_AHB); + + return ret; +} + +/** + * meson_spifc_hw_init() - reset and initialize the SPI controller + * @spifc: the Meson SPI device + */ +static void meson_spifc_hw_init(struct meson_spifc *spifc) +{ + /* reset device */ + regmap_update_bits(spifc->regmap, REG_SLAVE, SLAVE_SW_RST, + SLAVE_SW_RST); + /* disable compatible mode */ + regmap_update_bits(spifc->regmap, REG_USER, USER_CMP_MODE, 0); + /* set master mode */ + regmap_update_bits(spifc->regmap, REG_SLAVE, SLAVE_OP_MODE, 0); +} + +static int meson_spifc_probe(struct platform_device *pdev) +{ + struct spi_master *master; + struct meson_spifc *spifc; + struct resource *res; + void __iomem *base; + unsigned int rate; + int ret = 0; + + master = spi_alloc_master(&pdev->dev, sizeof(struct meson_spifc)); + if (!master) + return -ENOMEM; + + platform_set_drvdata(pdev, master); + + spifc = spi_master_get_devdata(master); + spifc->dev = &pdev->dev; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + base = devm_ioremap_resource(spifc->dev, res); + if (IS_ERR(base)) { + ret = PTR_ERR(base); + goto out_err; + } + + spifc->regmap = devm_regmap_init_mmio(spifc->dev, base, + &spifc_regmap_config); + if (IS_ERR(spifc->regmap)) { + ret = PTR_ERR(spifc->regmap); + goto out_err; + } + + spifc->clk = devm_clk_get(spifc->dev, NULL); + if (IS_ERR(spifc->clk)) { + dev_err(spifc->dev, "missing clock\n"); + ret = PTR_ERR(spifc->clk); + goto out_err; + } + + ret = clk_prepare_enable(spifc->clk); + if (ret) { + dev_err(spifc->dev, "can't prepare clock\n"); + goto out_err; + } + + rate = clk_get_rate(spifc->clk); + + master->num_chipselect = 1; + master->dev.of_node = pdev->dev.of_node; + master->bits_per_word_mask = SPI_BPW_MASK(8); + master->auto_runtime_pm = true; + master->transfer_one = meson_spifc_transfer_one; + master->min_speed_hz = rate >> 6; + master->max_speed_hz = rate >> 1; + + meson_spifc_hw_init(spifc); + + pm_runtime_set_active(spifc->dev); + pm_runtime_enable(spifc->dev); + + ret = devm_spi_register_master(spifc->dev, master); + if (ret) { + dev_err(spifc->dev, "failed to register spi master\n"); + goto out_clk; + } + + return 0; +out_clk: + clk_disable_unprepare(spifc->clk); +out_err: + spi_master_put(master); + return ret; +} + +static int meson_spifc_remove(struct platform_device *pdev) +{ + struct spi_master *master = platform_get_drvdata(pdev); + struct meson_spifc *spifc = spi_master_get_devdata(master); + + pm_runtime_get_sync(&pdev->dev); + clk_disable_unprepare(spifc->clk); + pm_runtime_disable(&pdev->dev); + + return 0; +} + +#ifdef CONFIG_PM_SLEEP +static int meson_spifc_suspend(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct meson_spifc *spifc = spi_master_get_devdata(master); + int ret; + + ret = spi_master_suspend(master); + if (ret) + return ret; + + if (!pm_runtime_suspended(dev)) + clk_disable_unprepare(spifc->clk); + + return 0; +} + +static int meson_spifc_resume(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct meson_spifc *spifc = spi_master_get_devdata(master); + int ret; + + if (!pm_runtime_suspended(dev)) { + ret = clk_prepare_enable(spifc->clk); + if (ret) + return ret; + } + + meson_spifc_hw_init(spifc); + + ret = spi_master_resume(master); + if (ret) + clk_disable_unprepare(spifc->clk); + + return ret; +} +#endif /* CONFIG_PM_SLEEP */ + +#ifdef CONFIG_PM +static int meson_spifc_runtime_suspend(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct meson_spifc *spifc = spi_master_get_devdata(master); + + clk_disable_unprepare(spifc->clk); + + return 0; +} + +static int meson_spifc_runtime_resume(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct meson_spifc *spifc = spi_master_get_devdata(master); + + return clk_prepare_enable(spifc->clk); +} +#endif /* CONFIG_PM */ + +static const struct dev_pm_ops meson_spifc_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(meson_spifc_suspend, meson_spifc_resume) + SET_RUNTIME_PM_OPS(meson_spifc_runtime_suspend, + meson_spifc_runtime_resume, + NULL) +}; + +static const struct of_device_id meson_spifc_dt_match[] = { + { .compatible = "amlogic,meson6-spifc", }, + { }, +}; + +static struct platform_driver meson_spifc_driver = { + .probe = meson_spifc_probe, + .remove = meson_spifc_remove, + .driver = { + .name = "meson-spifc", + .of_match_table = of_match_ptr(meson_spifc_dt_match), + .pm = &meson_spifc_pm_ops, + }, +}; + +module_platform_driver(meson_spifc_driver); + +MODULE_AUTHOR("Beniamino Galvani <b.galvani@gmail.com>"); +MODULE_DESCRIPTION("Amlogic Meson SPIFC driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/spi/spi-mpc512x-psc.c b/drivers/spi/spi-mpc512x-psc.c new file mode 100644 index 000000000..965d2bdcf --- /dev/null +++ b/drivers/spi/spi-mpc512x-psc.c @@ -0,0 +1,610 @@ +/* + * MPC512x PSC in SPI mode driver. + * + * Copyright (C) 2007,2008 Freescale Semiconductor Inc. + * Original port from 52xx driver: + * Hongjun Chen <hong-jun.chen@freescale.com> + * + * Fork of mpc52xx_psc_spi.c: + * Copyright (C) 2006 TOPTICA Photonics AG., Dragos Carp + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + */ + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/interrupt.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/of_platform.h> +#include <linux/completion.h> +#include <linux/io.h> +#include <linux/delay.h> +#include <linux/clk.h> +#include <linux/spi/spi.h> +#include <linux/fsl_devices.h> +#include <linux/gpio.h> +#include <asm/mpc52xx_psc.h> + +struct mpc512x_psc_spi { + void (*cs_control)(struct spi_device *spi, bool on); + + /* driver internal data */ + struct mpc52xx_psc __iomem *psc; + struct mpc512x_psc_fifo __iomem *fifo; + unsigned int irq; + u8 bits_per_word; + struct clk *clk_mclk; + struct clk *clk_ipg; + u32 mclk_rate; + + struct completion txisrdone; +}; + +/* controller state */ +struct mpc512x_psc_spi_cs { + int bits_per_word; + int speed_hz; +}; + +/* set clock freq, clock ramp, bits per work + * if t is NULL then reset the values to the default values + */ +static int mpc512x_psc_spi_transfer_setup(struct spi_device *spi, + struct spi_transfer *t) +{ + struct mpc512x_psc_spi_cs *cs = spi->controller_state; + + cs->speed_hz = (t && t->speed_hz) + ? t->speed_hz : spi->max_speed_hz; + cs->bits_per_word = (t && t->bits_per_word) + ? t->bits_per_word : spi->bits_per_word; + cs->bits_per_word = ((cs->bits_per_word + 7) / 8) * 8; + return 0; +} + +static void mpc512x_psc_spi_activate_cs(struct spi_device *spi) +{ + struct mpc512x_psc_spi_cs *cs = spi->controller_state; + struct mpc512x_psc_spi *mps = spi_master_get_devdata(spi->master); + struct mpc52xx_psc __iomem *psc = mps->psc; + u32 sicr; + u32 ccr; + int speed; + u16 bclkdiv; + + sicr = in_be32(&psc->sicr); + + /* Set clock phase and polarity */ + if (spi->mode & SPI_CPHA) + sicr |= 0x00001000; + else + sicr &= ~0x00001000; + + if (spi->mode & SPI_CPOL) + sicr |= 0x00002000; + else + sicr &= ~0x00002000; + + if (spi->mode & SPI_LSB_FIRST) + sicr |= 0x10000000; + else + sicr &= ~0x10000000; + out_be32(&psc->sicr, sicr); + + ccr = in_be32(&psc->ccr); + ccr &= 0xFF000000; + speed = cs->speed_hz; + if (!speed) + speed = 1000000; /* default 1MHz */ + bclkdiv = (mps->mclk_rate / speed) - 1; + + ccr |= (((bclkdiv & 0xff) << 16) | (((bclkdiv >> 8) & 0xff) << 8)); + out_be32(&psc->ccr, ccr); + mps->bits_per_word = cs->bits_per_word; + + if (mps->cs_control && gpio_is_valid(spi->cs_gpio)) + mps->cs_control(spi, (spi->mode & SPI_CS_HIGH) ? 1 : 0); +} + +static void mpc512x_psc_spi_deactivate_cs(struct spi_device *spi) +{ + struct mpc512x_psc_spi *mps = spi_master_get_devdata(spi->master); + + if (mps->cs_control && gpio_is_valid(spi->cs_gpio)) + mps->cs_control(spi, (spi->mode & SPI_CS_HIGH) ? 0 : 1); + +} + +/* extract and scale size field in txsz or rxsz */ +#define MPC512x_PSC_FIFO_SZ(sz) ((sz & 0x7ff) << 2); + +#define EOFBYTE 1 + +static int mpc512x_psc_spi_transfer_rxtx(struct spi_device *spi, + struct spi_transfer *t) +{ + struct mpc512x_psc_spi *mps = spi_master_get_devdata(spi->master); + struct mpc512x_psc_fifo __iomem *fifo = mps->fifo; + size_t tx_len = t->len; + size_t rx_len = t->len; + u8 *tx_buf = (u8 *)t->tx_buf; + u8 *rx_buf = (u8 *)t->rx_buf; + + if (!tx_buf && !rx_buf && t->len) + return -EINVAL; + + while (rx_len || tx_len) { + size_t txcount; + u8 data; + size_t fifosz; + size_t rxcount; + int rxtries; + + /* + * send the TX bytes in as large a chunk as possible + * but neither exceed the TX nor the RX FIFOs + */ + fifosz = MPC512x_PSC_FIFO_SZ(in_be32(&fifo->txsz)); + txcount = min(fifosz, tx_len); + fifosz = MPC512x_PSC_FIFO_SZ(in_be32(&fifo->rxsz)); + fifosz -= in_be32(&fifo->rxcnt) + 1; + txcount = min(fifosz, txcount); + if (txcount) { + + /* fill the TX FIFO */ + while (txcount-- > 0) { + data = tx_buf ? *tx_buf++ : 0; + if (tx_len == EOFBYTE && t->cs_change) + setbits32(&fifo->txcmd, + MPC512x_PSC_FIFO_EOF); + out_8(&fifo->txdata_8, data); + tx_len--; + } + + /* have the ISR trigger when the TX FIFO is empty */ + reinit_completion(&mps->txisrdone); + out_be32(&fifo->txisr, MPC512x_PSC_FIFO_EMPTY); + out_be32(&fifo->tximr, MPC512x_PSC_FIFO_EMPTY); + wait_for_completion(&mps->txisrdone); + } + + /* + * consume as much RX data as the FIFO holds, while we + * iterate over the transfer's TX data length + * + * only insist in draining all the remaining RX bytes + * when the TX bytes were exhausted (that's at the very + * end of this transfer, not when still iterating over + * the transfer's chunks) + */ + rxtries = 50; + do { + + /* + * grab whatever was in the FIFO when we started + * looking, don't bother fetching what was added to + * the FIFO while we read from it -- we'll return + * here eventually and prefer sending out remaining + * TX data + */ + fifosz = in_be32(&fifo->rxcnt); + rxcount = min(fifosz, rx_len); + while (rxcount-- > 0) { + data = in_8(&fifo->rxdata_8); + if (rx_buf) + *rx_buf++ = data; + rx_len--; + } + + /* + * come back later if there still is TX data to send, + * bail out of the RX drain loop if all of the TX data + * was sent and all of the RX data was received (i.e. + * when the transmission has completed) + */ + if (tx_len) + break; + if (!rx_len) + break; + + /* + * TX data transmission has completed while RX data + * is still pending -- that's a transient situation + * which depends on wire speed and specific + * hardware implementation details (buffering) yet + * should resolve very quickly + * + * just yield for a moment to not hog the CPU for + * too long when running SPI at low speed + * + * the timeout range is rather arbitrary and tries + * to balance throughput against system load; the + * chosen values result in a minimal timeout of 50 + * times 10us and thus work at speeds as low as + * some 20kbps, while the maximum timeout at the + * transfer's end could be 5ms _if_ nothing else + * ticks in the system _and_ RX data still wasn't + * received, which only occurs in situations that + * are exceptional; removing the unpredictability + * of the timeout either decreases throughput + * (longer timeouts), or puts more load on the + * system (fixed short timeouts) or requires the + * use of a timeout API instead of a counter and an + * unknown inner delay + */ + usleep_range(10, 100); + + } while (--rxtries > 0); + if (!tx_len && rx_len && !rxtries) { + /* + * not enough RX bytes even after several retries + * and the resulting rather long timeout? + */ + rxcount = in_be32(&fifo->rxcnt); + dev_warn(&spi->dev, + "short xfer, missing %zd RX bytes, FIFO level %zd\n", + rx_len, rxcount); + } + + /* + * drain and drop RX data which "should not be there" in + * the first place, for undisturbed transmission this turns + * into a NOP (except for the FIFO level fetch) + */ + if (!tx_len && !rx_len) { + while (in_be32(&fifo->rxcnt)) + in_8(&fifo->rxdata_8); + } + + } + return 0; +} + +static int mpc512x_psc_spi_msg_xfer(struct spi_master *master, + struct spi_message *m) +{ + struct spi_device *spi; + unsigned cs_change; + int status; + struct spi_transfer *t; + + spi = m->spi; + cs_change = 1; + status = 0; + list_for_each_entry(t, &m->transfers, transfer_list) { + if (t->bits_per_word || t->speed_hz) { + status = mpc512x_psc_spi_transfer_setup(spi, t); + if (status < 0) + break; + } + + if (cs_change) + mpc512x_psc_spi_activate_cs(spi); + cs_change = t->cs_change; + + status = mpc512x_psc_spi_transfer_rxtx(spi, t); + if (status) + break; + m->actual_length += t->len; + + if (t->delay_usecs) + udelay(t->delay_usecs); + + if (cs_change) + mpc512x_psc_spi_deactivate_cs(spi); + } + + m->status = status; + if (m->complete) + m->complete(m->context); + + if (status || !cs_change) + mpc512x_psc_spi_deactivate_cs(spi); + + mpc512x_psc_spi_transfer_setup(spi, NULL); + + spi_finalize_current_message(master); + return status; +} + +static int mpc512x_psc_spi_prep_xfer_hw(struct spi_master *master) +{ + struct mpc512x_psc_spi *mps = spi_master_get_devdata(master); + struct mpc52xx_psc __iomem *psc = mps->psc; + + dev_dbg(&master->dev, "%s()\n", __func__); + + /* Zero MR2 */ + in_8(&psc->mode); + out_8(&psc->mode, 0x0); + + /* enable transmitter/receiver */ + out_8(&psc->command, MPC52xx_PSC_TX_ENABLE | MPC52xx_PSC_RX_ENABLE); + + return 0; +} + +static int mpc512x_psc_spi_unprep_xfer_hw(struct spi_master *master) +{ + struct mpc512x_psc_spi *mps = spi_master_get_devdata(master); + struct mpc52xx_psc __iomem *psc = mps->psc; + struct mpc512x_psc_fifo __iomem *fifo = mps->fifo; + + dev_dbg(&master->dev, "%s()\n", __func__); + + /* disable transmitter/receiver and fifo interrupt */ + out_8(&psc->command, MPC52xx_PSC_TX_DISABLE | MPC52xx_PSC_RX_DISABLE); + out_be32(&fifo->tximr, 0); + + return 0; +} + +static int mpc512x_psc_spi_setup(struct spi_device *spi) +{ + struct mpc512x_psc_spi_cs *cs = spi->controller_state; + int ret; + + if (spi->bits_per_word % 8) + return -EINVAL; + + if (!cs) { + cs = kzalloc(sizeof *cs, GFP_KERNEL); + if (!cs) + return -ENOMEM; + + if (gpio_is_valid(spi->cs_gpio)) { + ret = gpio_request(spi->cs_gpio, dev_name(&spi->dev)); + if (ret) { + dev_err(&spi->dev, "can't get CS gpio: %d\n", + ret); + kfree(cs); + return ret; + } + gpio_direction_output(spi->cs_gpio, + spi->mode & SPI_CS_HIGH ? 0 : 1); + } + + spi->controller_state = cs; + } + + cs->bits_per_word = spi->bits_per_word; + cs->speed_hz = spi->max_speed_hz; + + return 0; +} + +static void mpc512x_psc_spi_cleanup(struct spi_device *spi) +{ + if (gpio_is_valid(spi->cs_gpio)) + gpio_free(spi->cs_gpio); + kfree(spi->controller_state); +} + +static int mpc512x_psc_spi_port_config(struct spi_master *master, + struct mpc512x_psc_spi *mps) +{ + struct mpc52xx_psc __iomem *psc = mps->psc; + struct mpc512x_psc_fifo __iomem *fifo = mps->fifo; + u32 sicr; + u32 ccr; + int speed; + u16 bclkdiv; + + /* Reset the PSC into a known state */ + out_8(&psc->command, MPC52xx_PSC_RST_RX); + out_8(&psc->command, MPC52xx_PSC_RST_TX); + out_8(&psc->command, MPC52xx_PSC_TX_DISABLE | MPC52xx_PSC_RX_DISABLE); + + /* Disable psc interrupts all useful interrupts are in fifo */ + out_be16(&psc->isr_imr.imr, 0); + + /* Disable fifo interrupts, will be enabled later */ + out_be32(&fifo->tximr, 0); + out_be32(&fifo->rximr, 0); + + /* Setup fifo slice address and size */ + /*out_be32(&fifo->txsz, 0x0fe00004);*/ + /*out_be32(&fifo->rxsz, 0x0ff00004);*/ + + sicr = 0x01000000 | /* SIM = 0001 -- 8 bit */ + 0x00800000 | /* GenClk = 1 -- internal clk */ + 0x00008000 | /* SPI = 1 */ + 0x00004000 | /* MSTR = 1 -- SPI master */ + 0x00000800; /* UseEOF = 1 -- SS low until EOF */ + + out_be32(&psc->sicr, sicr); + + ccr = in_be32(&psc->ccr); + ccr &= 0xFF000000; + speed = 1000000; /* default 1MHz */ + bclkdiv = (mps->mclk_rate / speed) - 1; + ccr |= (((bclkdiv & 0xff) << 16) | (((bclkdiv >> 8) & 0xff) << 8)); + out_be32(&psc->ccr, ccr); + + /* Set 2ms DTL delay */ + out_8(&psc->ctur, 0x00); + out_8(&psc->ctlr, 0x82); + + /* we don't use the alarms */ + out_be32(&fifo->rxalarm, 0xfff); + out_be32(&fifo->txalarm, 0); + + /* Enable FIFO slices for Rx/Tx */ + out_be32(&fifo->rxcmd, + MPC512x_PSC_FIFO_ENABLE_SLICE | MPC512x_PSC_FIFO_ENABLE_DMA); + out_be32(&fifo->txcmd, + MPC512x_PSC_FIFO_ENABLE_SLICE | MPC512x_PSC_FIFO_ENABLE_DMA); + + mps->bits_per_word = 8; + + return 0; +} + +static irqreturn_t mpc512x_psc_spi_isr(int irq, void *dev_id) +{ + struct mpc512x_psc_spi *mps = (struct mpc512x_psc_spi *)dev_id; + struct mpc512x_psc_fifo __iomem *fifo = mps->fifo; + + /* clear interrupt and wake up the rx/tx routine */ + if (in_be32(&fifo->txisr) & + in_be32(&fifo->tximr) & MPC512x_PSC_FIFO_EMPTY) { + out_be32(&fifo->txisr, MPC512x_PSC_FIFO_EMPTY); + out_be32(&fifo->tximr, 0); + complete(&mps->txisrdone); + return IRQ_HANDLED; + } + return IRQ_NONE; +} + +static void mpc512x_spi_cs_control(struct spi_device *spi, bool onoff) +{ + gpio_set_value(spi->cs_gpio, onoff); +} + +static int mpc512x_psc_spi_do_probe(struct device *dev, u32 regaddr, + u32 size, unsigned int irq) +{ + struct fsl_spi_platform_data *pdata = dev_get_platdata(dev); + struct mpc512x_psc_spi *mps; + struct spi_master *master; + int ret; + void *tempp; + struct clk *clk; + + master = spi_alloc_master(dev, sizeof *mps); + if (master == NULL) + return -ENOMEM; + + dev_set_drvdata(dev, master); + mps = spi_master_get_devdata(master); + mps->irq = irq; + + if (pdata == NULL) { + mps->cs_control = mpc512x_spi_cs_control; + } else { + mps->cs_control = pdata->cs_control; + master->bus_num = pdata->bus_num; + master->num_chipselect = pdata->max_chipselect; + } + + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LSB_FIRST; + master->setup = mpc512x_psc_spi_setup; + master->prepare_transfer_hardware = mpc512x_psc_spi_prep_xfer_hw; + master->transfer_one_message = mpc512x_psc_spi_msg_xfer; + master->unprepare_transfer_hardware = mpc512x_psc_spi_unprep_xfer_hw; + master->cleanup = mpc512x_psc_spi_cleanup; + master->dev.of_node = dev->of_node; + + tempp = devm_ioremap(dev, regaddr, size); + if (!tempp) { + dev_err(dev, "could not ioremap I/O port range\n"); + ret = -EFAULT; + goto free_master; + } + mps->psc = tempp; + mps->fifo = + (struct mpc512x_psc_fifo *)(tempp + sizeof(struct mpc52xx_psc)); + ret = devm_request_irq(dev, mps->irq, mpc512x_psc_spi_isr, IRQF_SHARED, + "mpc512x-psc-spi", mps); + if (ret) + goto free_master; + init_completion(&mps->txisrdone); + + clk = devm_clk_get(dev, "mclk"); + if (IS_ERR(clk)) { + ret = PTR_ERR(clk); + goto free_master; + } + ret = clk_prepare_enable(clk); + if (ret) + goto free_master; + mps->clk_mclk = clk; + mps->mclk_rate = clk_get_rate(clk); + + clk = devm_clk_get(dev, "ipg"); + if (IS_ERR(clk)) { + ret = PTR_ERR(clk); + goto free_mclk_clock; + } + ret = clk_prepare_enable(clk); + if (ret) + goto free_mclk_clock; + mps->clk_ipg = clk; + + ret = mpc512x_psc_spi_port_config(master, mps); + if (ret < 0) + goto free_ipg_clock; + + ret = devm_spi_register_master(dev, master); + if (ret < 0) + goto free_ipg_clock; + + return ret; + +free_ipg_clock: + clk_disable_unprepare(mps->clk_ipg); +free_mclk_clock: + clk_disable_unprepare(mps->clk_mclk); +free_master: + spi_master_put(master); + + return ret; +} + +static int mpc512x_psc_spi_do_remove(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct mpc512x_psc_spi *mps = spi_master_get_devdata(master); + + clk_disable_unprepare(mps->clk_mclk); + clk_disable_unprepare(mps->clk_ipg); + + return 0; +} + +static int mpc512x_psc_spi_of_probe(struct platform_device *op) +{ + const u32 *regaddr_p; + u64 regaddr64, size64; + + regaddr_p = of_get_address(op->dev.of_node, 0, &size64, NULL); + if (!regaddr_p) { + dev_err(&op->dev, "Invalid PSC address\n"); + return -EINVAL; + } + regaddr64 = of_translate_address(op->dev.of_node, regaddr_p); + + return mpc512x_psc_spi_do_probe(&op->dev, (u32) regaddr64, (u32) size64, + irq_of_parse_and_map(op->dev.of_node, 0)); +} + +static int mpc512x_psc_spi_of_remove(struct platform_device *op) +{ + return mpc512x_psc_spi_do_remove(&op->dev); +} + +static const struct of_device_id mpc512x_psc_spi_of_match[] = { + { .compatible = "fsl,mpc5121-psc-spi", }, + {}, +}; + +MODULE_DEVICE_TABLE(of, mpc512x_psc_spi_of_match); + +static struct platform_driver mpc512x_psc_spi_of_driver = { + .probe = mpc512x_psc_spi_of_probe, + .remove = mpc512x_psc_spi_of_remove, + .driver = { + .name = "mpc512x-psc-spi", + .of_match_table = mpc512x_psc_spi_of_match, + }, +}; +module_platform_driver(mpc512x_psc_spi_of_driver); + +MODULE_AUTHOR("John Rigby"); +MODULE_DESCRIPTION("MPC512x PSC SPI Driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/spi/spi-mpc52xx-psc.c b/drivers/spi/spi-mpc52xx-psc.c new file mode 100644 index 000000000..72d11ebef --- /dev/null +++ b/drivers/spi/spi-mpc52xx-psc.c @@ -0,0 +1,518 @@ +/* + * MPC52xx PSC in SPI mode driver. + * + * Maintainer: Dragos Carp + * + * Copyright (C) 2006 TOPTICA Photonics AG. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + */ + +#include <linux/module.h> +#include <linux/types.h> +#include <linux/errno.h> +#include <linux/interrupt.h> +#include <linux/of_address.h> +#include <linux/of_platform.h> +#include <linux/workqueue.h> +#include <linux/completion.h> +#include <linux/io.h> +#include <linux/delay.h> +#include <linux/spi/spi.h> +#include <linux/fsl_devices.h> +#include <linux/slab.h> + +#include <asm/mpc52xx.h> +#include <asm/mpc52xx_psc.h> + +#define MCLK 20000000 /* PSC port MClk in hz */ + +struct mpc52xx_psc_spi { + /* fsl_spi_platform data */ + void (*cs_control)(struct spi_device *spi, bool on); + u32 sysclk; + + /* driver internal data */ + struct mpc52xx_psc __iomem *psc; + struct mpc52xx_psc_fifo __iomem *fifo; + unsigned int irq; + u8 bits_per_word; + u8 busy; + + struct workqueue_struct *workqueue; + struct work_struct work; + + struct list_head queue; + spinlock_t lock; + + struct completion done; +}; + +/* controller state */ +struct mpc52xx_psc_spi_cs { + int bits_per_word; + int speed_hz; +}; + +/* set clock freq, clock ramp, bits per work + * if t is NULL then reset the values to the default values + */ +static int mpc52xx_psc_spi_transfer_setup(struct spi_device *spi, + struct spi_transfer *t) +{ + struct mpc52xx_psc_spi_cs *cs = spi->controller_state; + + cs->speed_hz = (t && t->speed_hz) + ? t->speed_hz : spi->max_speed_hz; + cs->bits_per_word = (t && t->bits_per_word) + ? t->bits_per_word : spi->bits_per_word; + cs->bits_per_word = ((cs->bits_per_word + 7) / 8) * 8; + return 0; +} + +static void mpc52xx_psc_spi_activate_cs(struct spi_device *spi) +{ + struct mpc52xx_psc_spi_cs *cs = spi->controller_state; + struct mpc52xx_psc_spi *mps = spi_master_get_devdata(spi->master); + struct mpc52xx_psc __iomem *psc = mps->psc; + u32 sicr; + u16 ccr; + + sicr = in_be32(&psc->sicr); + + /* Set clock phase and polarity */ + if (spi->mode & SPI_CPHA) + sicr |= 0x00001000; + else + sicr &= ~0x00001000; + if (spi->mode & SPI_CPOL) + sicr |= 0x00002000; + else + sicr &= ~0x00002000; + + if (spi->mode & SPI_LSB_FIRST) + sicr |= 0x10000000; + else + sicr &= ~0x10000000; + out_be32(&psc->sicr, sicr); + + /* Set clock frequency and bits per word + * Because psc->ccr is defined as 16bit register instead of 32bit + * just set the lower byte of BitClkDiv + */ + ccr = in_be16((u16 __iomem *)&psc->ccr); + ccr &= 0xFF00; + if (cs->speed_hz) + ccr |= (MCLK / cs->speed_hz - 1) & 0xFF; + else /* by default SPI Clk 1MHz */ + ccr |= (MCLK / 1000000 - 1) & 0xFF; + out_be16((u16 __iomem *)&psc->ccr, ccr); + mps->bits_per_word = cs->bits_per_word; + + if (mps->cs_control) + mps->cs_control(spi, (spi->mode & SPI_CS_HIGH) ? 1 : 0); +} + +static void mpc52xx_psc_spi_deactivate_cs(struct spi_device *spi) +{ + struct mpc52xx_psc_spi *mps = spi_master_get_devdata(spi->master); + + if (mps->cs_control) + mps->cs_control(spi, (spi->mode & SPI_CS_HIGH) ? 0 : 1); +} + +#define MPC52xx_PSC_BUFSIZE (MPC52xx_PSC_RFNUM_MASK + 1) +/* wake up when 80% fifo full */ +#define MPC52xx_PSC_RFALARM (MPC52xx_PSC_BUFSIZE * 20 / 100) + +static int mpc52xx_psc_spi_transfer_rxtx(struct spi_device *spi, + struct spi_transfer *t) +{ + struct mpc52xx_psc_spi *mps = spi_master_get_devdata(spi->master); + struct mpc52xx_psc __iomem *psc = mps->psc; + struct mpc52xx_psc_fifo __iomem *fifo = mps->fifo; + unsigned rb = 0; /* number of bytes receieved */ + unsigned sb = 0; /* number of bytes sent */ + unsigned char *rx_buf = (unsigned char *)t->rx_buf; + unsigned char *tx_buf = (unsigned char *)t->tx_buf; + unsigned rfalarm; + unsigned send_at_once = MPC52xx_PSC_BUFSIZE; + unsigned recv_at_once; + int last_block = 0; + + if (!t->tx_buf && !t->rx_buf && t->len) + return -EINVAL; + + /* enable transmiter/receiver */ + out_8(&psc->command, MPC52xx_PSC_TX_ENABLE | MPC52xx_PSC_RX_ENABLE); + while (rb < t->len) { + if (t->len - rb > MPC52xx_PSC_BUFSIZE) { + rfalarm = MPC52xx_PSC_RFALARM; + last_block = 0; + } else { + send_at_once = t->len - sb; + rfalarm = MPC52xx_PSC_BUFSIZE - (t->len - rb); + last_block = 1; + } + + dev_dbg(&spi->dev, "send %d bytes...\n", send_at_once); + for (; send_at_once; sb++, send_at_once--) { + /* set EOF flag before the last word is sent */ + if (send_at_once == 1 && last_block) + out_8(&psc->ircr2, 0x01); + + if (tx_buf) + out_8(&psc->mpc52xx_psc_buffer_8, tx_buf[sb]); + else + out_8(&psc->mpc52xx_psc_buffer_8, 0); + } + + + /* enable interrupts and wait for wake up + * if just one byte is expected the Rx FIFO genererates no + * FFULL interrupt, so activate the RxRDY interrupt + */ + out_8(&psc->command, MPC52xx_PSC_SEL_MODE_REG_1); + if (t->len - rb == 1) { + out_8(&psc->mode, 0); + } else { + out_8(&psc->mode, MPC52xx_PSC_MODE_FFULL); + out_be16(&fifo->rfalarm, rfalarm); + } + out_be16(&psc->mpc52xx_psc_imr, MPC52xx_PSC_IMR_RXRDY); + wait_for_completion(&mps->done); + recv_at_once = in_be16(&fifo->rfnum); + dev_dbg(&spi->dev, "%d bytes received\n", recv_at_once); + + send_at_once = recv_at_once; + if (rx_buf) { + for (; recv_at_once; rb++, recv_at_once--) + rx_buf[rb] = in_8(&psc->mpc52xx_psc_buffer_8); + } else { + for (; recv_at_once; rb++, recv_at_once--) + in_8(&psc->mpc52xx_psc_buffer_8); + } + } + /* disable transmiter/receiver */ + out_8(&psc->command, MPC52xx_PSC_TX_DISABLE | MPC52xx_PSC_RX_DISABLE); + + return 0; +} + +static void mpc52xx_psc_spi_work(struct work_struct *work) +{ + struct mpc52xx_psc_spi *mps = + container_of(work, struct mpc52xx_psc_spi, work); + + spin_lock_irq(&mps->lock); + mps->busy = 1; + while (!list_empty(&mps->queue)) { + struct spi_message *m; + struct spi_device *spi; + struct spi_transfer *t = NULL; + unsigned cs_change; + int status; + + m = container_of(mps->queue.next, struct spi_message, queue); + list_del_init(&m->queue); + spin_unlock_irq(&mps->lock); + + spi = m->spi; + cs_change = 1; + status = 0; + list_for_each_entry (t, &m->transfers, transfer_list) { + if (t->bits_per_word || t->speed_hz) { + status = mpc52xx_psc_spi_transfer_setup(spi, t); + if (status < 0) + break; + } + + if (cs_change) + mpc52xx_psc_spi_activate_cs(spi); + cs_change = t->cs_change; + + status = mpc52xx_psc_spi_transfer_rxtx(spi, t); + if (status) + break; + m->actual_length += t->len; + + if (t->delay_usecs) + udelay(t->delay_usecs); + + if (cs_change) + mpc52xx_psc_spi_deactivate_cs(spi); + } + + m->status = status; + if (m->complete) + m->complete(m->context); + + if (status || !cs_change) + mpc52xx_psc_spi_deactivate_cs(spi); + + mpc52xx_psc_spi_transfer_setup(spi, NULL); + + spin_lock_irq(&mps->lock); + } + mps->busy = 0; + spin_unlock_irq(&mps->lock); +} + +static int mpc52xx_psc_spi_setup(struct spi_device *spi) +{ + struct mpc52xx_psc_spi *mps = spi_master_get_devdata(spi->master); + struct mpc52xx_psc_spi_cs *cs = spi->controller_state; + unsigned long flags; + + if (spi->bits_per_word%8) + return -EINVAL; + + if (!cs) { + cs = kzalloc(sizeof *cs, GFP_KERNEL); + if (!cs) + return -ENOMEM; + spi->controller_state = cs; + } + + cs->bits_per_word = spi->bits_per_word; + cs->speed_hz = spi->max_speed_hz; + + spin_lock_irqsave(&mps->lock, flags); + if (!mps->busy) + mpc52xx_psc_spi_deactivate_cs(spi); + spin_unlock_irqrestore(&mps->lock, flags); + + return 0; +} + +static int mpc52xx_psc_spi_transfer(struct spi_device *spi, + struct spi_message *m) +{ + struct mpc52xx_psc_spi *mps = spi_master_get_devdata(spi->master); + unsigned long flags; + + m->actual_length = 0; + m->status = -EINPROGRESS; + + spin_lock_irqsave(&mps->lock, flags); + list_add_tail(&m->queue, &mps->queue); + queue_work(mps->workqueue, &mps->work); + spin_unlock_irqrestore(&mps->lock, flags); + + return 0; +} + +static void mpc52xx_psc_spi_cleanup(struct spi_device *spi) +{ + kfree(spi->controller_state); +} + +static int mpc52xx_psc_spi_port_config(int psc_id, struct mpc52xx_psc_spi *mps) +{ + struct mpc52xx_psc __iomem *psc = mps->psc; + struct mpc52xx_psc_fifo __iomem *fifo = mps->fifo; + u32 mclken_div; + int ret; + + /* default sysclk is 512MHz */ + mclken_div = (mps->sysclk ? mps->sysclk : 512000000) / MCLK; + ret = mpc52xx_set_psc_clkdiv(psc_id, mclken_div); + if (ret) + return ret; + + /* Reset the PSC into a known state */ + out_8(&psc->command, MPC52xx_PSC_RST_RX); + out_8(&psc->command, MPC52xx_PSC_RST_TX); + out_8(&psc->command, MPC52xx_PSC_TX_DISABLE | MPC52xx_PSC_RX_DISABLE); + + /* Disable interrupts, interrupts are based on alarm level */ + out_be16(&psc->mpc52xx_psc_imr, 0); + out_8(&psc->command, MPC52xx_PSC_SEL_MODE_REG_1); + out_8(&fifo->rfcntl, 0); + out_8(&psc->mode, MPC52xx_PSC_MODE_FFULL); + + /* Configure 8bit codec mode as a SPI master and use EOF flags */ + /* SICR_SIM_CODEC8|SICR_GENCLK|SICR_SPI|SICR_MSTR|SICR_USEEOF */ + out_be32(&psc->sicr, 0x0180C800); + out_be16((u16 __iomem *)&psc->ccr, 0x070F); /* default SPI Clk 1MHz */ + + /* Set 2ms DTL delay */ + out_8(&psc->ctur, 0x00); + out_8(&psc->ctlr, 0x84); + + mps->bits_per_word = 8; + + return 0; +} + +static irqreturn_t mpc52xx_psc_spi_isr(int irq, void *dev_id) +{ + struct mpc52xx_psc_spi *mps = (struct mpc52xx_psc_spi *)dev_id; + struct mpc52xx_psc __iomem *psc = mps->psc; + + /* disable interrupt and wake up the work queue */ + if (in_be16(&psc->mpc52xx_psc_isr) & MPC52xx_PSC_IMR_RXRDY) { + out_be16(&psc->mpc52xx_psc_imr, 0); + complete(&mps->done); + return IRQ_HANDLED; + } + return IRQ_NONE; +} + +/* bus_num is used only for the case dev->platform_data == NULL */ +static int mpc52xx_psc_spi_do_probe(struct device *dev, u32 regaddr, + u32 size, unsigned int irq, s16 bus_num) +{ + struct fsl_spi_platform_data *pdata = dev_get_platdata(dev); + struct mpc52xx_psc_spi *mps; + struct spi_master *master; + int ret; + + master = spi_alloc_master(dev, sizeof *mps); + if (master == NULL) + return -ENOMEM; + + dev_set_drvdata(dev, master); + mps = spi_master_get_devdata(master); + + /* the spi->mode bits understood by this driver: */ + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LSB_FIRST; + + mps->irq = irq; + if (pdata == NULL) { + dev_warn(dev, + "probe called without platform data, no cs_control function will be called\n"); + mps->cs_control = NULL; + mps->sysclk = 0; + master->bus_num = bus_num; + master->num_chipselect = 255; + } else { + mps->cs_control = pdata->cs_control; + mps->sysclk = pdata->sysclk; + master->bus_num = pdata->bus_num; + master->num_chipselect = pdata->max_chipselect; + } + master->setup = mpc52xx_psc_spi_setup; + master->transfer = mpc52xx_psc_spi_transfer; + master->cleanup = mpc52xx_psc_spi_cleanup; + master->dev.of_node = dev->of_node; + + mps->psc = ioremap(regaddr, size); + if (!mps->psc) { + dev_err(dev, "could not ioremap I/O port range\n"); + ret = -EFAULT; + goto free_master; + } + /* On the 5200, fifo regs are immediately ajacent to the psc regs */ + mps->fifo = ((void __iomem *)mps->psc) + sizeof(struct mpc52xx_psc); + + ret = request_irq(mps->irq, mpc52xx_psc_spi_isr, 0, "mpc52xx-psc-spi", + mps); + if (ret) + goto free_master; + + ret = mpc52xx_psc_spi_port_config(master->bus_num, mps); + if (ret < 0) { + dev_err(dev, "can't configure PSC! Is it capable of SPI?\n"); + goto free_irq; + } + + spin_lock_init(&mps->lock); + init_completion(&mps->done); + INIT_WORK(&mps->work, mpc52xx_psc_spi_work); + INIT_LIST_HEAD(&mps->queue); + + mps->workqueue = create_singlethread_workqueue( + dev_name(master->dev.parent)); + if (mps->workqueue == NULL) { + ret = -EBUSY; + goto free_irq; + } + + ret = spi_register_master(master); + if (ret < 0) + goto unreg_master; + + return ret; + +unreg_master: + destroy_workqueue(mps->workqueue); +free_irq: + free_irq(mps->irq, mps); +free_master: + if (mps->psc) + iounmap(mps->psc); + spi_master_put(master); + + return ret; +} + +static int mpc52xx_psc_spi_of_probe(struct platform_device *op) +{ + const u32 *regaddr_p; + u64 regaddr64, size64; + s16 id = -1; + + regaddr_p = of_get_address(op->dev.of_node, 0, &size64, NULL); + if (!regaddr_p) { + dev_err(&op->dev, "Invalid PSC address\n"); + return -EINVAL; + } + regaddr64 = of_translate_address(op->dev.of_node, regaddr_p); + + /* get PSC id (1..6, used by port_config) */ + if (op->dev.platform_data == NULL) { + const u32 *psc_nump; + + psc_nump = of_get_property(op->dev.of_node, "cell-index", NULL); + if (!psc_nump || *psc_nump > 5) { + dev_err(&op->dev, "Invalid cell-index property\n"); + return -EINVAL; + } + id = *psc_nump + 1; + } + + return mpc52xx_psc_spi_do_probe(&op->dev, (u32)regaddr64, (u32)size64, + irq_of_parse_and_map(op->dev.of_node, 0), id); +} + +static int mpc52xx_psc_spi_of_remove(struct platform_device *op) +{ + struct spi_master *master = spi_master_get(platform_get_drvdata(op)); + struct mpc52xx_psc_spi *mps = spi_master_get_devdata(master); + + flush_workqueue(mps->workqueue); + destroy_workqueue(mps->workqueue); + spi_unregister_master(master); + free_irq(mps->irq, mps); + if (mps->psc) + iounmap(mps->psc); + spi_master_put(master); + + return 0; +} + +static const struct of_device_id mpc52xx_psc_spi_of_match[] = { + { .compatible = "fsl,mpc5200-psc-spi", }, + { .compatible = "mpc5200-psc-spi", }, /* old */ + {} +}; + +MODULE_DEVICE_TABLE(of, mpc52xx_psc_spi_of_match); + +static struct platform_driver mpc52xx_psc_spi_of_driver = { + .probe = mpc52xx_psc_spi_of_probe, + .remove = mpc52xx_psc_spi_of_remove, + .driver = { + .name = "mpc52xx-psc-spi", + .of_match_table = mpc52xx_psc_spi_of_match, + }, +}; +module_platform_driver(mpc52xx_psc_spi_of_driver); + +MODULE_AUTHOR("Dragos Carp"); +MODULE_DESCRIPTION("MPC52xx PSC SPI Driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/spi/spi-mpc52xx.c b/drivers/spi/spi-mpc52xx.c new file mode 100644 index 000000000..c36002110 --- /dev/null +++ b/drivers/spi/spi-mpc52xx.c @@ -0,0 +1,551 @@ +/* + * MPC52xx SPI bus driver. + * + * Copyright (C) 2008 Secret Lab Technologies Ltd. + * + * This file is released under the GPLv2 + * + * This is the driver for the MPC5200's dedicated SPI controller. + * + * Note: this driver does not support the MPC5200 PSC in SPI mode. For + * that driver see drivers/spi/mpc52xx_psc_spi.c + */ + +#include <linux/module.h> +#include <linux/errno.h> +#include <linux/of_platform.h> +#include <linux/interrupt.h> +#include <linux/delay.h> +#include <linux/spi/spi.h> +#include <linux/io.h> +#include <linux/of_gpio.h> +#include <linux/slab.h> +#include <asm/time.h> +#include <asm/mpc52xx.h> + +MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>"); +MODULE_DESCRIPTION("MPC52xx SPI (non-PSC) Driver"); +MODULE_LICENSE("GPL"); + +/* Register offsets */ +#define SPI_CTRL1 0x00 +#define SPI_CTRL1_SPIE (1 << 7) +#define SPI_CTRL1_SPE (1 << 6) +#define SPI_CTRL1_MSTR (1 << 4) +#define SPI_CTRL1_CPOL (1 << 3) +#define SPI_CTRL1_CPHA (1 << 2) +#define SPI_CTRL1_SSOE (1 << 1) +#define SPI_CTRL1_LSBFE (1 << 0) + +#define SPI_CTRL2 0x01 +#define SPI_BRR 0x04 + +#define SPI_STATUS 0x05 +#define SPI_STATUS_SPIF (1 << 7) +#define SPI_STATUS_WCOL (1 << 6) +#define SPI_STATUS_MODF (1 << 4) + +#define SPI_DATA 0x09 +#define SPI_PORTDATA 0x0d +#define SPI_DATADIR 0x10 + +/* FSM state return values */ +#define FSM_STOP 0 /* Nothing more for the state machine to */ + /* do. If something interesting happens */ + /* then an IRQ will be received */ +#define FSM_POLL 1 /* need to poll for completion, an IRQ is */ + /* not expected */ +#define FSM_CONTINUE 2 /* Keep iterating the state machine */ + +/* Driver internal data */ +struct mpc52xx_spi { + struct spi_master *master; + void __iomem *regs; + int irq0; /* MODF irq */ + int irq1; /* SPIF irq */ + unsigned int ipb_freq; + + /* Statistics; not used now, but will be reintroduced for debugfs */ + int msg_count; + int wcol_count; + int wcol_ticks; + u32 wcol_tx_timestamp; + int modf_count; + int byte_count; + + struct list_head queue; /* queue of pending messages */ + spinlock_t lock; + struct work_struct work; + + /* Details of current transfer (length, and buffer pointers) */ + struct spi_message *message; /* current message */ + struct spi_transfer *transfer; /* current transfer */ + int (*state)(int irq, struct mpc52xx_spi *ms, u8 status, u8 data); + int len; + int timestamp; + u8 *rx_buf; + const u8 *tx_buf; + int cs_change; + int gpio_cs_count; + unsigned int *gpio_cs; +}; + +/* + * CS control function + */ +static void mpc52xx_spi_chipsel(struct mpc52xx_spi *ms, int value) +{ + int cs; + + if (ms->gpio_cs_count > 0) { + cs = ms->message->spi->chip_select; + gpio_set_value(ms->gpio_cs[cs], value ? 0 : 1); + } else + out_8(ms->regs + SPI_PORTDATA, value ? 0 : 0x08); +} + +/* + * Start a new transfer. This is called both by the idle state + * for the first transfer in a message, and by the wait state when the + * previous transfer in a message is complete. + */ +static void mpc52xx_spi_start_transfer(struct mpc52xx_spi *ms) +{ + ms->rx_buf = ms->transfer->rx_buf; + ms->tx_buf = ms->transfer->tx_buf; + ms->len = ms->transfer->len; + + /* Activate the chip select */ + if (ms->cs_change) + mpc52xx_spi_chipsel(ms, 1); + ms->cs_change = ms->transfer->cs_change; + + /* Write out the first byte */ + ms->wcol_tx_timestamp = get_tbl(); + if (ms->tx_buf) + out_8(ms->regs + SPI_DATA, *ms->tx_buf++); + else + out_8(ms->regs + SPI_DATA, 0); +} + +/* Forward declaration of state handlers */ +static int mpc52xx_spi_fsmstate_transfer(int irq, struct mpc52xx_spi *ms, + u8 status, u8 data); +static int mpc52xx_spi_fsmstate_wait(int irq, struct mpc52xx_spi *ms, + u8 status, u8 data); + +/* + * IDLE state + * + * No transfers are in progress; if another transfer is pending then retrieve + * it and kick it off. Otherwise, stop processing the state machine + */ +static int +mpc52xx_spi_fsmstate_idle(int irq, struct mpc52xx_spi *ms, u8 status, u8 data) +{ + struct spi_device *spi; + int spr, sppr; + u8 ctrl1; + + if (status && (irq != NO_IRQ)) + dev_err(&ms->master->dev, "spurious irq, status=0x%.2x\n", + status); + + /* Check if there is another transfer waiting. */ + if (list_empty(&ms->queue)) + return FSM_STOP; + + /* get the head of the queue */ + ms->message = list_first_entry(&ms->queue, struct spi_message, queue); + list_del_init(&ms->message->queue); + + /* Setup the controller parameters */ + ctrl1 = SPI_CTRL1_SPIE | SPI_CTRL1_SPE | SPI_CTRL1_MSTR; + spi = ms->message->spi; + if (spi->mode & SPI_CPHA) + ctrl1 |= SPI_CTRL1_CPHA; + if (spi->mode & SPI_CPOL) + ctrl1 |= SPI_CTRL1_CPOL; + if (spi->mode & SPI_LSB_FIRST) + ctrl1 |= SPI_CTRL1_LSBFE; + out_8(ms->regs + SPI_CTRL1, ctrl1); + + /* Setup the controller speed */ + /* minimum divider is '2'. Also, add '1' to force rounding the + * divider up. */ + sppr = ((ms->ipb_freq / ms->message->spi->max_speed_hz) + 1) >> 1; + spr = 0; + if (sppr < 1) + sppr = 1; + while (((sppr - 1) & ~0x7) != 0) { + sppr = (sppr + 1) >> 1; /* add '1' to force rounding up */ + spr++; + } + sppr--; /* sppr quantity in register is offset by 1 */ + if (spr > 7) { + /* Don't overrun limits of SPI baudrate register */ + spr = 7; + sppr = 7; + } + out_8(ms->regs + SPI_BRR, sppr << 4 | spr); /* Set speed */ + + ms->cs_change = 1; + ms->transfer = container_of(ms->message->transfers.next, + struct spi_transfer, transfer_list); + + mpc52xx_spi_start_transfer(ms); + ms->state = mpc52xx_spi_fsmstate_transfer; + + return FSM_CONTINUE; +} + +/* + * TRANSFER state + * + * In the middle of a transfer. If the SPI core has completed processing + * a byte, then read out the received data and write out the next byte + * (unless this transfer is finished; in which case go on to the wait + * state) + */ +static int mpc52xx_spi_fsmstate_transfer(int irq, struct mpc52xx_spi *ms, + u8 status, u8 data) +{ + if (!status) + return ms->irq0 ? FSM_STOP : FSM_POLL; + + if (status & SPI_STATUS_WCOL) { + /* The SPI controller is stoopid. At slower speeds, it may + * raise the SPIF flag before the state machine is actually + * finished, which causes a collision (internal to the state + * machine only). The manual recommends inserting a delay + * between receiving the interrupt and sending the next byte, + * but it can also be worked around simply by retrying the + * transfer which is what we do here. */ + ms->wcol_count++; + ms->wcol_ticks += get_tbl() - ms->wcol_tx_timestamp; + ms->wcol_tx_timestamp = get_tbl(); + data = 0; + if (ms->tx_buf) + data = *(ms->tx_buf - 1); + out_8(ms->regs + SPI_DATA, data); /* try again */ + return FSM_CONTINUE; + } else if (status & SPI_STATUS_MODF) { + ms->modf_count++; + dev_err(&ms->master->dev, "mode fault\n"); + mpc52xx_spi_chipsel(ms, 0); + ms->message->status = -EIO; + if (ms->message->complete) + ms->message->complete(ms->message->context); + ms->state = mpc52xx_spi_fsmstate_idle; + return FSM_CONTINUE; + } + + /* Read data out of the spi device */ + ms->byte_count++; + if (ms->rx_buf) + *ms->rx_buf++ = data; + + /* Is the transfer complete? */ + ms->len--; + if (ms->len == 0) { + ms->timestamp = get_tbl(); + ms->timestamp += ms->transfer->delay_usecs * tb_ticks_per_usec; + ms->state = mpc52xx_spi_fsmstate_wait; + return FSM_CONTINUE; + } + + /* Write out the next byte */ + ms->wcol_tx_timestamp = get_tbl(); + if (ms->tx_buf) + out_8(ms->regs + SPI_DATA, *ms->tx_buf++); + else + out_8(ms->regs + SPI_DATA, 0); + + return FSM_CONTINUE; +} + +/* + * WAIT state + * + * A transfer has completed; need to wait for the delay period to complete + * before starting the next transfer + */ +static int +mpc52xx_spi_fsmstate_wait(int irq, struct mpc52xx_spi *ms, u8 status, u8 data) +{ + if (status && irq) + dev_err(&ms->master->dev, "spurious irq, status=0x%.2x\n", + status); + + if (((int)get_tbl()) - ms->timestamp < 0) + return FSM_POLL; + + ms->message->actual_length += ms->transfer->len; + + /* Check if there is another transfer in this message. If there + * aren't then deactivate CS, notify sender, and drop back to idle + * to start the next message. */ + if (ms->transfer->transfer_list.next == &ms->message->transfers) { + ms->msg_count++; + mpc52xx_spi_chipsel(ms, 0); + ms->message->status = 0; + if (ms->message->complete) + ms->message->complete(ms->message->context); + ms->state = mpc52xx_spi_fsmstate_idle; + return FSM_CONTINUE; + } + + /* There is another transfer; kick it off */ + + if (ms->cs_change) + mpc52xx_spi_chipsel(ms, 0); + + ms->transfer = container_of(ms->transfer->transfer_list.next, + struct spi_transfer, transfer_list); + mpc52xx_spi_start_transfer(ms); + ms->state = mpc52xx_spi_fsmstate_transfer; + return FSM_CONTINUE; +} + +/** + * mpc52xx_spi_fsm_process - Finite State Machine iteration function + * @irq: irq number that triggered the FSM or 0 for polling + * @ms: pointer to mpc52xx_spi driver data + */ +static void mpc52xx_spi_fsm_process(int irq, struct mpc52xx_spi *ms) +{ + int rc = FSM_CONTINUE; + u8 status, data; + + while (rc == FSM_CONTINUE) { + /* Interrupt cleared by read of STATUS followed by + * read of DATA registers */ + status = in_8(ms->regs + SPI_STATUS); + data = in_8(ms->regs + SPI_DATA); + rc = ms->state(irq, ms, status, data); + } + + if (rc == FSM_POLL) + schedule_work(&ms->work); +} + +/** + * mpc52xx_spi_irq - IRQ handler + */ +static irqreturn_t mpc52xx_spi_irq(int irq, void *_ms) +{ + struct mpc52xx_spi *ms = _ms; + spin_lock(&ms->lock); + mpc52xx_spi_fsm_process(irq, ms); + spin_unlock(&ms->lock); + return IRQ_HANDLED; +} + +/** + * mpc52xx_spi_wq - Workqueue function for polling the state machine + */ +static void mpc52xx_spi_wq(struct work_struct *work) +{ + struct mpc52xx_spi *ms = container_of(work, struct mpc52xx_spi, work); + unsigned long flags; + + spin_lock_irqsave(&ms->lock, flags); + mpc52xx_spi_fsm_process(0, ms); + spin_unlock_irqrestore(&ms->lock, flags); +} + +/* + * spi_master ops + */ + +static int mpc52xx_spi_transfer(struct spi_device *spi, struct spi_message *m) +{ + struct mpc52xx_spi *ms = spi_master_get_devdata(spi->master); + unsigned long flags; + + m->actual_length = 0; + m->status = -EINPROGRESS; + + spin_lock_irqsave(&ms->lock, flags); + list_add_tail(&m->queue, &ms->queue); + spin_unlock_irqrestore(&ms->lock, flags); + schedule_work(&ms->work); + + return 0; +} + +/* + * OF Platform Bus Binding + */ +static int mpc52xx_spi_probe(struct platform_device *op) +{ + struct spi_master *master; + struct mpc52xx_spi *ms; + void __iomem *regs; + u8 ctrl1; + int rc, i = 0; + int gpio_cs; + + /* MMIO registers */ + dev_dbg(&op->dev, "probing mpc5200 SPI device\n"); + regs = of_iomap(op->dev.of_node, 0); + if (!regs) + return -ENODEV; + + /* initialize the device */ + ctrl1 = SPI_CTRL1_SPIE | SPI_CTRL1_SPE | SPI_CTRL1_MSTR; + out_8(regs + SPI_CTRL1, ctrl1); + out_8(regs + SPI_CTRL2, 0x0); + out_8(regs + SPI_DATADIR, 0xe); /* Set output pins */ + out_8(regs + SPI_PORTDATA, 0x8); /* Deassert /SS signal */ + + /* Clear the status register and re-read it to check for a MODF + * failure. This driver cannot currently handle multiple masters + * on the SPI bus. This fault will also occur if the SPI signals + * are not connected to any pins (port_config setting) */ + in_8(regs + SPI_STATUS); + out_8(regs + SPI_CTRL1, ctrl1); + + in_8(regs + SPI_DATA); + if (in_8(regs + SPI_STATUS) & SPI_STATUS_MODF) { + dev_err(&op->dev, "mode fault; is port_config correct?\n"); + rc = -EIO; + goto err_init; + } + + dev_dbg(&op->dev, "allocating spi_master struct\n"); + master = spi_alloc_master(&op->dev, sizeof *ms); + if (!master) { + rc = -ENOMEM; + goto err_alloc; + } + + master->transfer = mpc52xx_spi_transfer; + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST; + master->bits_per_word_mask = SPI_BPW_MASK(8); + master->dev.of_node = op->dev.of_node; + + platform_set_drvdata(op, master); + + ms = spi_master_get_devdata(master); + ms->master = master; + ms->regs = regs; + ms->irq0 = irq_of_parse_and_map(op->dev.of_node, 0); + ms->irq1 = irq_of_parse_and_map(op->dev.of_node, 1); + ms->state = mpc52xx_spi_fsmstate_idle; + ms->ipb_freq = mpc5xxx_get_bus_frequency(op->dev.of_node); + ms->gpio_cs_count = of_gpio_count(op->dev.of_node); + if (ms->gpio_cs_count > 0) { + master->num_chipselect = ms->gpio_cs_count; + ms->gpio_cs = kmalloc(ms->gpio_cs_count * sizeof(unsigned int), + GFP_KERNEL); + if (!ms->gpio_cs) { + rc = -ENOMEM; + goto err_alloc_gpio; + } + + for (i = 0; i < ms->gpio_cs_count; i++) { + gpio_cs = of_get_gpio(op->dev.of_node, i); + if (gpio_cs < 0) { + dev_err(&op->dev, + "could not parse the gpio field " + "in oftree\n"); + rc = -ENODEV; + goto err_gpio; + } + + rc = gpio_request(gpio_cs, dev_name(&op->dev)); + if (rc) { + dev_err(&op->dev, + "can't request spi cs gpio #%d " + "on gpio line %d\n", i, gpio_cs); + goto err_gpio; + } + + gpio_direction_output(gpio_cs, 1); + ms->gpio_cs[i] = gpio_cs; + } + } + + spin_lock_init(&ms->lock); + INIT_LIST_HEAD(&ms->queue); + INIT_WORK(&ms->work, mpc52xx_spi_wq); + + /* Decide if interrupts can be used */ + if (ms->irq0 && ms->irq1) { + rc = request_irq(ms->irq0, mpc52xx_spi_irq, 0, + "mpc5200-spi-modf", ms); + rc |= request_irq(ms->irq1, mpc52xx_spi_irq, 0, + "mpc5200-spi-spif", ms); + if (rc) { + free_irq(ms->irq0, ms); + free_irq(ms->irq1, ms); + ms->irq0 = ms->irq1 = 0; + } + } else { + /* operate in polled mode */ + ms->irq0 = ms->irq1 = 0; + } + + if (!ms->irq0) + dev_info(&op->dev, "using polled mode\n"); + + dev_dbg(&op->dev, "registering spi_master struct\n"); + rc = spi_register_master(master); + if (rc) + goto err_register; + + dev_info(&ms->master->dev, "registered MPC5200 SPI bus\n"); + + return rc; + + err_register: + dev_err(&ms->master->dev, "initialization failed\n"); + err_gpio: + while (i-- > 0) + gpio_free(ms->gpio_cs[i]); + + kfree(ms->gpio_cs); + err_alloc_gpio: + spi_master_put(master); + err_alloc: + err_init: + iounmap(regs); + return rc; +} + +static int mpc52xx_spi_remove(struct platform_device *op) +{ + struct spi_master *master = spi_master_get(platform_get_drvdata(op)); + struct mpc52xx_spi *ms = spi_master_get_devdata(master); + int i; + + free_irq(ms->irq0, ms); + free_irq(ms->irq1, ms); + + for (i = 0; i < ms->gpio_cs_count; i++) + gpio_free(ms->gpio_cs[i]); + + kfree(ms->gpio_cs); + spi_unregister_master(master); + iounmap(ms->regs); + spi_master_put(master); + + return 0; +} + +static const struct of_device_id mpc52xx_spi_match[] = { + { .compatible = "fsl,mpc5200-spi", }, + {} +}; +MODULE_DEVICE_TABLE(of, mpc52xx_spi_match); + +static struct platform_driver mpc52xx_spi_of_driver = { + .driver = { + .name = "mpc52xx-spi", + .of_match_table = mpc52xx_spi_match, + }, + .probe = mpc52xx_spi_probe, + .remove = mpc52xx_spi_remove, +}; +module_platform_driver(mpc52xx_spi_of_driver); diff --git a/drivers/spi/spi-mxs.c b/drivers/spi/spi-mxs.c new file mode 100644 index 000000000..5b0e9a3e8 --- /dev/null +++ b/drivers/spi/spi-mxs.c @@ -0,0 +1,583 @@ +/* + * Freescale MXS SPI master driver + * + * Copyright 2012 DENX Software Engineering, GmbH. + * Copyright 2012 Freescale Semiconductor, Inc. + * Copyright 2008 Embedded Alley Solutions, Inc All Rights Reserved. + * + * Rework and transition to new API by: + * Marek Vasut <marex@denx.de> + * + * Based on previous attempt by: + * Fabio Estevam <fabio.estevam@freescale.com> + * + * Based on code from U-Boot bootloader by: + * Marek Vasut <marex@denx.de> + * + * Based on spi-stmp.c, which is: + * Author: Dmitry Pervushin <dimka@embeddedalley.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/kernel.h> +#include <linux/ioport.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/of_gpio.h> +#include <linux/platform_device.h> +#include <linux/delay.h> +#include <linux/interrupt.h> +#include <linux/dma-mapping.h> +#include <linux/dmaengine.h> +#include <linux/highmem.h> +#include <linux/clk.h> +#include <linux/err.h> +#include <linux/completion.h> +#include <linux/gpio.h> +#include <linux/regulator/consumer.h> +#include <linux/module.h> +#include <linux/stmp_device.h> +#include <linux/spi/spi.h> +#include <linux/spi/mxs-spi.h> + +#define DRIVER_NAME "mxs-spi" + +/* Use 10S timeout for very long transfers, it should suffice. */ +#define SSP_TIMEOUT 10000 + +#define SG_MAXLEN 0xff00 + +/* + * Flags for txrx functions. More efficient that using an argument register for + * each one. + */ +#define TXRX_WRITE (1<<0) /* This is a write */ +#define TXRX_DEASSERT_CS (1<<1) /* De-assert CS at end of txrx */ + +struct mxs_spi { + struct mxs_ssp ssp; + struct completion c; + unsigned int sck; /* Rate requested (vs actual) */ +}; + +static int mxs_spi_setup_transfer(struct spi_device *dev, + const struct spi_transfer *t) +{ + struct mxs_spi *spi = spi_master_get_devdata(dev->master); + struct mxs_ssp *ssp = &spi->ssp; + const unsigned int hz = min(dev->max_speed_hz, t->speed_hz); + + if (hz == 0) { + dev_err(&dev->dev, "SPI clock rate of zero not allowed\n"); + return -EINVAL; + } + + if (hz != spi->sck) { + mxs_ssp_set_clk_rate(ssp, hz); + /* + * Save requested rate, hz, rather than the actual rate, + * ssp->clk_rate. Otherwise we would set the rate every transfer + * when the actual rate is not quite the same as requested rate. + */ + spi->sck = hz; + /* + * Perhaps we should return an error if the actual clock is + * nowhere close to what was requested? + */ + } + + writel(BM_SSP_CTRL0_LOCK_CS, + ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_SET); + + writel(BF_SSP_CTRL1_SSP_MODE(BV_SSP_CTRL1_SSP_MODE__SPI) | + BF_SSP_CTRL1_WORD_LENGTH(BV_SSP_CTRL1_WORD_LENGTH__EIGHT_BITS) | + ((dev->mode & SPI_CPOL) ? BM_SSP_CTRL1_POLARITY : 0) | + ((dev->mode & SPI_CPHA) ? BM_SSP_CTRL1_PHASE : 0), + ssp->base + HW_SSP_CTRL1(ssp)); + + writel(0x0, ssp->base + HW_SSP_CMD0); + writel(0x0, ssp->base + HW_SSP_CMD1); + + return 0; +} + +static u32 mxs_spi_cs_to_reg(unsigned cs) +{ + u32 select = 0; + + /* + * i.MX28 Datasheet: 17.10.1: HW_SSP_CTRL0 + * + * The bits BM_SSP_CTRL0_WAIT_FOR_CMD and BM_SSP_CTRL0_WAIT_FOR_IRQ + * in HW_SSP_CTRL0 register do have multiple usage, please refer to + * the datasheet for further details. In SPI mode, they are used to + * toggle the chip-select lines (nCS pins). + */ + if (cs & 1) + select |= BM_SSP_CTRL0_WAIT_FOR_CMD; + if (cs & 2) + select |= BM_SSP_CTRL0_WAIT_FOR_IRQ; + + return select; +} + +static int mxs_ssp_wait(struct mxs_spi *spi, int offset, int mask, bool set) +{ + const unsigned long timeout = jiffies + msecs_to_jiffies(SSP_TIMEOUT); + struct mxs_ssp *ssp = &spi->ssp; + u32 reg; + + do { + reg = readl_relaxed(ssp->base + offset); + + if (!set) + reg = ~reg; + + reg &= mask; + + if (reg == mask) + return 0; + } while (time_before(jiffies, timeout)); + + return -ETIMEDOUT; +} + +static void mxs_ssp_dma_irq_callback(void *param) +{ + struct mxs_spi *spi = param; + + complete(&spi->c); +} + +static irqreturn_t mxs_ssp_irq_handler(int irq, void *dev_id) +{ + struct mxs_ssp *ssp = dev_id; + + dev_err(ssp->dev, "%s[%i] CTRL1=%08x STATUS=%08x\n", + __func__, __LINE__, + readl(ssp->base + HW_SSP_CTRL1(ssp)), + readl(ssp->base + HW_SSP_STATUS(ssp))); + return IRQ_HANDLED; +} + +static int mxs_spi_txrx_dma(struct mxs_spi *spi, + unsigned char *buf, int len, + unsigned int flags) +{ + struct mxs_ssp *ssp = &spi->ssp; + struct dma_async_tx_descriptor *desc = NULL; + const bool vmalloced_buf = is_vmalloc_addr(buf); + const int desc_len = vmalloced_buf ? PAGE_SIZE : SG_MAXLEN; + const int sgs = DIV_ROUND_UP(len, desc_len); + int sg_count; + int min, ret; + u32 ctrl0; + struct page *vm_page; + struct { + u32 pio[4]; + struct scatterlist sg; + } *dma_xfer; + + if (!len) + return -EINVAL; + + dma_xfer = kcalloc(sgs, sizeof(*dma_xfer), GFP_KERNEL); + if (!dma_xfer) + return -ENOMEM; + + reinit_completion(&spi->c); + + /* Chip select was already programmed into CTRL0 */ + ctrl0 = readl(ssp->base + HW_SSP_CTRL0); + ctrl0 &= ~(BM_SSP_CTRL0_XFER_COUNT | BM_SSP_CTRL0_IGNORE_CRC | + BM_SSP_CTRL0_READ); + ctrl0 |= BM_SSP_CTRL0_DATA_XFER; + + if (!(flags & TXRX_WRITE)) + ctrl0 |= BM_SSP_CTRL0_READ; + + /* Queue the DMA data transfer. */ + for (sg_count = 0; sg_count < sgs; sg_count++) { + /* Prepare the transfer descriptor. */ + min = min(len, desc_len); + + /* + * De-assert CS on last segment if flag is set (i.e., no more + * transfers will follow) + */ + if ((sg_count + 1 == sgs) && (flags & TXRX_DEASSERT_CS)) + ctrl0 |= BM_SSP_CTRL0_IGNORE_CRC; + + if (ssp->devid == IMX23_SSP) { + ctrl0 &= ~BM_SSP_CTRL0_XFER_COUNT; + ctrl0 |= min; + } + + dma_xfer[sg_count].pio[0] = ctrl0; + dma_xfer[sg_count].pio[3] = min; + + if (vmalloced_buf) { + vm_page = vmalloc_to_page(buf); + if (!vm_page) { + ret = -ENOMEM; + goto err_vmalloc; + } + + sg_init_table(&dma_xfer[sg_count].sg, 1); + sg_set_page(&dma_xfer[sg_count].sg, vm_page, + min, offset_in_page(buf)); + } else { + sg_init_one(&dma_xfer[sg_count].sg, buf, min); + } + + ret = dma_map_sg(ssp->dev, &dma_xfer[sg_count].sg, 1, + (flags & TXRX_WRITE) ? DMA_TO_DEVICE : DMA_FROM_DEVICE); + + len -= min; + buf += min; + + /* Queue the PIO register write transfer. */ + desc = dmaengine_prep_slave_sg(ssp->dmach, + (struct scatterlist *)dma_xfer[sg_count].pio, + (ssp->devid == IMX23_SSP) ? 1 : 4, + DMA_TRANS_NONE, + sg_count ? DMA_PREP_INTERRUPT : 0); + if (!desc) { + dev_err(ssp->dev, + "Failed to get PIO reg. write descriptor.\n"); + ret = -EINVAL; + goto err_mapped; + } + + desc = dmaengine_prep_slave_sg(ssp->dmach, + &dma_xfer[sg_count].sg, 1, + (flags & TXRX_WRITE) ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + + if (!desc) { + dev_err(ssp->dev, + "Failed to get DMA data write descriptor.\n"); + ret = -EINVAL; + goto err_mapped; + } + } + + /* + * The last descriptor must have this callback, + * to finish the DMA transaction. + */ + desc->callback = mxs_ssp_dma_irq_callback; + desc->callback_param = spi; + + /* Start the transfer. */ + dmaengine_submit(desc); + dma_async_issue_pending(ssp->dmach); + + if (!wait_for_completion_timeout(&spi->c, + msecs_to_jiffies(SSP_TIMEOUT))) { + dev_err(ssp->dev, "DMA transfer timeout\n"); + ret = -ETIMEDOUT; + dmaengine_terminate_all(ssp->dmach); + goto err_vmalloc; + } + + ret = 0; + +err_vmalloc: + while (--sg_count >= 0) { +err_mapped: + dma_unmap_sg(ssp->dev, &dma_xfer[sg_count].sg, 1, + (flags & TXRX_WRITE) ? DMA_TO_DEVICE : DMA_FROM_DEVICE); + } + + kfree(dma_xfer); + + return ret; +} + +static int mxs_spi_txrx_pio(struct mxs_spi *spi, + unsigned char *buf, int len, + unsigned int flags) +{ + struct mxs_ssp *ssp = &spi->ssp; + + writel(BM_SSP_CTRL0_IGNORE_CRC, + ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_CLR); + + while (len--) { + if (len == 0 && (flags & TXRX_DEASSERT_CS)) + writel(BM_SSP_CTRL0_IGNORE_CRC, + ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_SET); + + if (ssp->devid == IMX23_SSP) { + writel(BM_SSP_CTRL0_XFER_COUNT, + ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_CLR); + writel(1, + ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_SET); + } else { + writel(1, ssp->base + HW_SSP_XFER_SIZE); + } + + if (flags & TXRX_WRITE) + writel(BM_SSP_CTRL0_READ, + ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_CLR); + else + writel(BM_SSP_CTRL0_READ, + ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_SET); + + writel(BM_SSP_CTRL0_RUN, + ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_SET); + + if (mxs_ssp_wait(spi, HW_SSP_CTRL0, BM_SSP_CTRL0_RUN, 1)) + return -ETIMEDOUT; + + if (flags & TXRX_WRITE) + writel(*buf, ssp->base + HW_SSP_DATA(ssp)); + + writel(BM_SSP_CTRL0_DATA_XFER, + ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_SET); + + if (!(flags & TXRX_WRITE)) { + if (mxs_ssp_wait(spi, HW_SSP_STATUS(ssp), + BM_SSP_STATUS_FIFO_EMPTY, 0)) + return -ETIMEDOUT; + + *buf = (readl(ssp->base + HW_SSP_DATA(ssp)) & 0xff); + } + + if (mxs_ssp_wait(spi, HW_SSP_CTRL0, BM_SSP_CTRL0_RUN, 0)) + return -ETIMEDOUT; + + buf++; + } + + if (len <= 0) + return 0; + + return -ETIMEDOUT; +} + +static int mxs_spi_transfer_one(struct spi_master *master, + struct spi_message *m) +{ + struct mxs_spi *spi = spi_master_get_devdata(master); + struct mxs_ssp *ssp = &spi->ssp; + struct spi_transfer *t; + unsigned int flag; + int status = 0; + + /* Program CS register bits here, it will be used for all transfers. */ + writel(BM_SSP_CTRL0_WAIT_FOR_CMD | BM_SSP_CTRL0_WAIT_FOR_IRQ, + ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_CLR); + writel(mxs_spi_cs_to_reg(m->spi->chip_select), + ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_SET); + + list_for_each_entry(t, &m->transfers, transfer_list) { + + status = mxs_spi_setup_transfer(m->spi, t); + if (status) + break; + + /* De-assert on last transfer, inverted by cs_change flag */ + flag = (&t->transfer_list == m->transfers.prev) ^ t->cs_change ? + TXRX_DEASSERT_CS : 0; + + /* + * Small blocks can be transfered via PIO. + * Measured by empiric means: + * + * dd if=/dev/mtdblock0 of=/dev/null bs=1024k count=1 + * + * DMA only: 2.164808 seconds, 473.0KB/s + * Combined: 1.676276 seconds, 610.9KB/s + */ + if (t->len < 32) { + writel(BM_SSP_CTRL1_DMA_ENABLE, + ssp->base + HW_SSP_CTRL1(ssp) + + STMP_OFFSET_REG_CLR); + + if (t->tx_buf) + status = mxs_spi_txrx_pio(spi, + (void *)t->tx_buf, + t->len, flag | TXRX_WRITE); + if (t->rx_buf) + status = mxs_spi_txrx_pio(spi, + t->rx_buf, t->len, + flag); + } else { + writel(BM_SSP_CTRL1_DMA_ENABLE, + ssp->base + HW_SSP_CTRL1(ssp) + + STMP_OFFSET_REG_SET); + + if (t->tx_buf) + status = mxs_spi_txrx_dma(spi, + (void *)t->tx_buf, t->len, + flag | TXRX_WRITE); + if (t->rx_buf) + status = mxs_spi_txrx_dma(spi, + t->rx_buf, t->len, + flag); + } + + if (status) { + stmp_reset_block(ssp->base); + break; + } + + m->actual_length += t->len; + } + + m->status = status; + spi_finalize_current_message(master); + + return status; +} + +static const struct of_device_id mxs_spi_dt_ids[] = { + { .compatible = "fsl,imx23-spi", .data = (void *) IMX23_SSP, }, + { .compatible = "fsl,imx28-spi", .data = (void *) IMX28_SSP, }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, mxs_spi_dt_ids); + +static int mxs_spi_probe(struct platform_device *pdev) +{ + const struct of_device_id *of_id = + of_match_device(mxs_spi_dt_ids, &pdev->dev); + struct device_node *np = pdev->dev.of_node; + struct spi_master *master; + struct mxs_spi *spi; + struct mxs_ssp *ssp; + struct resource *iores; + struct clk *clk; + void __iomem *base; + int devid, clk_freq; + int ret = 0, irq_err; + + /* + * Default clock speed for the SPI core. 160MHz seems to + * work reasonably well with most SPI flashes, so use this + * as a default. Override with "clock-frequency" DT prop. + */ + const int clk_freq_default = 160000000; + + iores = platform_get_resource(pdev, IORESOURCE_MEM, 0); + irq_err = platform_get_irq(pdev, 0); + if (irq_err < 0) + return irq_err; + + base = devm_ioremap_resource(&pdev->dev, iores); + if (IS_ERR(base)) + return PTR_ERR(base); + + clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(clk)) + return PTR_ERR(clk); + + devid = (enum mxs_ssp_id) of_id->data; + ret = of_property_read_u32(np, "clock-frequency", + &clk_freq); + if (ret) + clk_freq = clk_freq_default; + + master = spi_alloc_master(&pdev->dev, sizeof(*spi)); + if (!master) + return -ENOMEM; + + master->transfer_one_message = mxs_spi_transfer_one; + master->bits_per_word_mask = SPI_BPW_MASK(8); + master->mode_bits = SPI_CPOL | SPI_CPHA; + master->num_chipselect = 3; + master->dev.of_node = np; + master->flags = SPI_MASTER_HALF_DUPLEX; + + spi = spi_master_get_devdata(master); + ssp = &spi->ssp; + ssp->dev = &pdev->dev; + ssp->clk = clk; + ssp->base = base; + ssp->devid = devid; + + init_completion(&spi->c); + + ret = devm_request_irq(&pdev->dev, irq_err, mxs_ssp_irq_handler, 0, + dev_name(&pdev->dev), ssp); + if (ret) + goto out_master_free; + + ssp->dmach = dma_request_slave_channel(&pdev->dev, "rx-tx"); + if (!ssp->dmach) { + dev_err(ssp->dev, "Failed to request DMA\n"); + ret = -ENODEV; + goto out_master_free; + } + + ret = clk_prepare_enable(ssp->clk); + if (ret) + goto out_dma_release; + + clk_set_rate(ssp->clk, clk_freq); + + ret = stmp_reset_block(ssp->base); + if (ret) + goto out_disable_clk; + + platform_set_drvdata(pdev, master); + + ret = devm_spi_register_master(&pdev->dev, master); + if (ret) { + dev_err(&pdev->dev, "Cannot register SPI master, %d\n", ret); + goto out_disable_clk; + } + + return 0; + +out_disable_clk: + clk_disable_unprepare(ssp->clk); +out_dma_release: + dma_release_channel(ssp->dmach); +out_master_free: + spi_master_put(master); + return ret; +} + +static int mxs_spi_remove(struct platform_device *pdev) +{ + struct spi_master *master; + struct mxs_spi *spi; + struct mxs_ssp *ssp; + + master = platform_get_drvdata(pdev); + spi = spi_master_get_devdata(master); + ssp = &spi->ssp; + + clk_disable_unprepare(ssp->clk); + dma_release_channel(ssp->dmach); + + return 0; +} + +static struct platform_driver mxs_spi_driver = { + .probe = mxs_spi_probe, + .remove = mxs_spi_remove, + .driver = { + .name = DRIVER_NAME, + .of_match_table = mxs_spi_dt_ids, + }, +}; + +module_platform_driver(mxs_spi_driver); + +MODULE_AUTHOR("Marek Vasut <marex@denx.de>"); +MODULE_DESCRIPTION("MXS SPI master driver"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:mxs-spi"); diff --git a/drivers/spi/spi-nuc900.c b/drivers/spi/spi-nuc900.c new file mode 100644 index 000000000..f51a058e7 --- /dev/null +++ b/drivers/spi/spi-nuc900.c @@ -0,0 +1,433 @@ +/* + * Copyright (c) 2009 Nuvoton technology. + * Wan ZongShun <mcuos.com@gmail.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + */ + +#include <linux/module.h> +#include <linux/spinlock.h> +#include <linux/interrupt.h> +#include <linux/delay.h> +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/clk.h> +#include <linux/device.h> +#include <linux/platform_device.h> +#include <linux/gpio.h> +#include <linux/io.h> +#include <linux/slab.h> + +#include <linux/spi/spi.h> +#include <linux/spi/spi_bitbang.h> + +#include <linux/platform_data/spi-nuc900.h> + +/* usi registers offset */ +#define USI_CNT 0x00 +#define USI_DIV 0x04 +#define USI_SSR 0x08 +#define USI_RX0 0x10 +#define USI_TX0 0x10 + +/* usi register bit */ +#define ENINT (0x01 << 17) +#define ENFLG (0x01 << 16) +#define SLEEP (0x0f << 12) +#define TXNUM (0x03 << 8) +#define TXBITLEN (0x1f << 3) +#define TXNEG (0x01 << 2) +#define RXNEG (0x01 << 1) +#define LSB (0x01 << 10) +#define SELECTLEV (0x01 << 2) +#define SELECTPOL (0x01 << 31) +#define SELECTSLAVE 0x01 +#define GOBUSY 0x01 + +struct nuc900_spi { + struct spi_bitbang bitbang; + struct completion done; + void __iomem *regs; + int irq; + int len; + int count; + const unsigned char *tx; + unsigned char *rx; + struct clk *clk; + struct spi_master *master; + struct nuc900_spi_info *pdata; + spinlock_t lock; +}; + +static inline struct nuc900_spi *to_hw(struct spi_device *sdev) +{ + return spi_master_get_devdata(sdev->master); +} + +static void nuc900_slave_select(struct spi_device *spi, unsigned int ssr) +{ + struct nuc900_spi *hw = to_hw(spi); + unsigned int val; + unsigned int cs = spi->mode & SPI_CS_HIGH ? 1 : 0; + unsigned int cpol = spi->mode & SPI_CPOL ? 1 : 0; + unsigned long flags; + + spin_lock_irqsave(&hw->lock, flags); + + val = __raw_readl(hw->regs + USI_SSR); + + if (!cs) + val &= ~SELECTLEV; + else + val |= SELECTLEV; + + if (!ssr) + val &= ~SELECTSLAVE; + else + val |= SELECTSLAVE; + + __raw_writel(val, hw->regs + USI_SSR); + + val = __raw_readl(hw->regs + USI_CNT); + + if (!cpol) + val &= ~SELECTPOL; + else + val |= SELECTPOL; + + __raw_writel(val, hw->regs + USI_CNT); + + spin_unlock_irqrestore(&hw->lock, flags); +} + +static void nuc900_spi_chipsel(struct spi_device *spi, int value) +{ + switch (value) { + case BITBANG_CS_INACTIVE: + nuc900_slave_select(spi, 0); + break; + + case BITBANG_CS_ACTIVE: + nuc900_slave_select(spi, 1); + break; + } +} + +static void nuc900_spi_setup_txnum(struct nuc900_spi *hw, unsigned int txnum) +{ + unsigned int val; + unsigned long flags; + + spin_lock_irqsave(&hw->lock, flags); + + val = __raw_readl(hw->regs + USI_CNT) & ~TXNUM; + + if (txnum) + val |= txnum << 0x08; + + __raw_writel(val, hw->regs + USI_CNT); + + spin_unlock_irqrestore(&hw->lock, flags); + +} + +static void nuc900_spi_setup_txbitlen(struct nuc900_spi *hw, + unsigned int txbitlen) +{ + unsigned int val; + unsigned long flags; + + spin_lock_irqsave(&hw->lock, flags); + + val = __raw_readl(hw->regs + USI_CNT) & ~TXBITLEN; + + val |= (txbitlen << 0x03); + + __raw_writel(val, hw->regs + USI_CNT); + + spin_unlock_irqrestore(&hw->lock, flags); +} + +static void nuc900_spi_gobusy(struct nuc900_spi *hw) +{ + unsigned int val; + unsigned long flags; + + spin_lock_irqsave(&hw->lock, flags); + + val = __raw_readl(hw->regs + USI_CNT); + + val |= GOBUSY; + + __raw_writel(val, hw->regs + USI_CNT); + + spin_unlock_irqrestore(&hw->lock, flags); +} + +static inline unsigned int hw_txbyte(struct nuc900_spi *hw, int count) +{ + return hw->tx ? hw->tx[count] : 0; +} + +static int nuc900_spi_txrx(struct spi_device *spi, struct spi_transfer *t) +{ + struct nuc900_spi *hw = to_hw(spi); + + hw->tx = t->tx_buf; + hw->rx = t->rx_buf; + hw->len = t->len; + hw->count = 0; + + __raw_writel(hw_txbyte(hw, 0x0), hw->regs + USI_TX0); + + nuc900_spi_gobusy(hw); + + wait_for_completion(&hw->done); + + return hw->count; +} + +static irqreturn_t nuc900_spi_irq(int irq, void *dev) +{ + struct nuc900_spi *hw = dev; + unsigned int status; + unsigned int count = hw->count; + + status = __raw_readl(hw->regs + USI_CNT); + __raw_writel(status, hw->regs + USI_CNT); + + if (status & ENFLG) { + hw->count++; + + if (hw->rx) + hw->rx[count] = __raw_readl(hw->regs + USI_RX0); + count++; + + if (count < hw->len) { + __raw_writel(hw_txbyte(hw, count), hw->regs + USI_TX0); + nuc900_spi_gobusy(hw); + } else { + complete(&hw->done); + } + + return IRQ_HANDLED; + } + + complete(&hw->done); + return IRQ_HANDLED; +} + +static void nuc900_tx_edge(struct nuc900_spi *hw, unsigned int edge) +{ + unsigned int val; + unsigned long flags; + + spin_lock_irqsave(&hw->lock, flags); + + val = __raw_readl(hw->regs + USI_CNT); + + if (edge) + val |= TXNEG; + else + val &= ~TXNEG; + __raw_writel(val, hw->regs + USI_CNT); + + spin_unlock_irqrestore(&hw->lock, flags); +} + +static void nuc900_rx_edge(struct nuc900_spi *hw, unsigned int edge) +{ + unsigned int val; + unsigned long flags; + + spin_lock_irqsave(&hw->lock, flags); + + val = __raw_readl(hw->regs + USI_CNT); + + if (edge) + val |= RXNEG; + else + val &= ~RXNEG; + __raw_writel(val, hw->regs + USI_CNT); + + spin_unlock_irqrestore(&hw->lock, flags); +} + +static void nuc900_send_first(struct nuc900_spi *hw, unsigned int lsb) +{ + unsigned int val; + unsigned long flags; + + spin_lock_irqsave(&hw->lock, flags); + + val = __raw_readl(hw->regs + USI_CNT); + + if (lsb) + val |= LSB; + else + val &= ~LSB; + __raw_writel(val, hw->regs + USI_CNT); + + spin_unlock_irqrestore(&hw->lock, flags); +} + +static void nuc900_set_sleep(struct nuc900_spi *hw, unsigned int sleep) +{ + unsigned int val; + unsigned long flags; + + spin_lock_irqsave(&hw->lock, flags); + + val = __raw_readl(hw->regs + USI_CNT) & ~SLEEP; + + if (sleep) + val |= (sleep << 12); + + __raw_writel(val, hw->regs + USI_CNT); + + spin_unlock_irqrestore(&hw->lock, flags); +} + +static void nuc900_enable_int(struct nuc900_spi *hw) +{ + unsigned int val; + unsigned long flags; + + spin_lock_irqsave(&hw->lock, flags); + + val = __raw_readl(hw->regs + USI_CNT); + + val |= ENINT; + + __raw_writel(val, hw->regs + USI_CNT); + + spin_unlock_irqrestore(&hw->lock, flags); +} + +static void nuc900_set_divider(struct nuc900_spi *hw) +{ + __raw_writel(hw->pdata->divider, hw->regs + USI_DIV); +} + +static void nuc900_init_spi(struct nuc900_spi *hw) +{ + clk_enable(hw->clk); + spin_lock_init(&hw->lock); + + nuc900_tx_edge(hw, hw->pdata->txneg); + nuc900_rx_edge(hw, hw->pdata->rxneg); + nuc900_send_first(hw, hw->pdata->lsb); + nuc900_set_sleep(hw, hw->pdata->sleep); + nuc900_spi_setup_txbitlen(hw, hw->pdata->txbitlen); + nuc900_spi_setup_txnum(hw, hw->pdata->txnum); + nuc900_set_divider(hw); + nuc900_enable_int(hw); +} + +static int nuc900_spi_probe(struct platform_device *pdev) +{ + struct nuc900_spi *hw; + struct spi_master *master; + struct resource *res; + int err = 0; + + master = spi_alloc_master(&pdev->dev, sizeof(struct nuc900_spi)); + if (master == NULL) { + dev_err(&pdev->dev, "No memory for spi_master\n"); + return -ENOMEM; + } + + hw = spi_master_get_devdata(master); + hw->master = master; + hw->pdata = dev_get_platdata(&pdev->dev); + + if (hw->pdata == NULL) { + dev_err(&pdev->dev, "No platform data supplied\n"); + err = -ENOENT; + goto err_pdata; + } + + platform_set_drvdata(pdev, hw); + init_completion(&hw->done); + + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH; + if (hw->pdata->lsb) + master->mode_bits |= SPI_LSB_FIRST; + master->num_chipselect = hw->pdata->num_cs; + master->bus_num = hw->pdata->bus_num; + hw->bitbang.master = hw->master; + hw->bitbang.chipselect = nuc900_spi_chipsel; + hw->bitbang.txrx_bufs = nuc900_spi_txrx; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + hw->regs = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(hw->regs)) { + err = PTR_ERR(hw->regs); + goto err_pdata; + } + + hw->irq = platform_get_irq(pdev, 0); + if (hw->irq < 0) { + dev_err(&pdev->dev, "No IRQ specified\n"); + err = -ENOENT; + goto err_pdata; + } + + err = devm_request_irq(&pdev->dev, hw->irq, nuc900_spi_irq, 0, + pdev->name, hw); + if (err) { + dev_err(&pdev->dev, "Cannot claim IRQ\n"); + goto err_pdata; + } + + hw->clk = devm_clk_get(&pdev->dev, "spi"); + if (IS_ERR(hw->clk)) { + dev_err(&pdev->dev, "No clock for device\n"); + err = PTR_ERR(hw->clk); + goto err_pdata; + } + + mfp_set_groupg(&pdev->dev, NULL); + nuc900_init_spi(hw); + + err = spi_bitbang_start(&hw->bitbang); + if (err) { + dev_err(&pdev->dev, "Failed to register SPI master\n"); + goto err_register; + } + + return 0; + +err_register: + clk_disable(hw->clk); +err_pdata: + spi_master_put(hw->master); + return err; +} + +static int nuc900_spi_remove(struct platform_device *dev) +{ + struct nuc900_spi *hw = platform_get_drvdata(dev); + + spi_bitbang_stop(&hw->bitbang); + clk_disable(hw->clk); + spi_master_put(hw->master); + return 0; +} + +static struct platform_driver nuc900_spi_driver = { + .probe = nuc900_spi_probe, + .remove = nuc900_spi_remove, + .driver = { + .name = "nuc900-spi", + }, +}; +module_platform_driver(nuc900_spi_driver); + +MODULE_AUTHOR("Wan ZongShun <mcuos.com@gmail.com>"); +MODULE_DESCRIPTION("nuc900 spi driver!"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:nuc900-spi"); diff --git a/drivers/spi/spi-oc-tiny.c b/drivers/spi/spi-oc-tiny.c new file mode 100644 index 000000000..76656a77e --- /dev/null +++ b/drivers/spi/spi-oc-tiny.c @@ -0,0 +1,363 @@ +/* + * OpenCores tiny SPI master driver + * + * http://opencores.org/project,tiny_spi + * + * Copyright (C) 2011 Thomas Chou <thomas@wytron.com.tw> + * + * Based on spi_s3c24xx.c, which is: + * Copyright (c) 2006 Ben Dooks + * Copyright (c) 2006 Simtec Electronics + * Ben Dooks <ben@simtec.co.uk> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/interrupt.h> +#include <linux/errno.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/spi/spi.h> +#include <linux/spi/spi_bitbang.h> +#include <linux/spi/spi_oc_tiny.h> +#include <linux/io.h> +#include <linux/gpio.h> +#include <linux/of.h> + +#define DRV_NAME "spi_oc_tiny" + +#define TINY_SPI_RXDATA 0 +#define TINY_SPI_TXDATA 4 +#define TINY_SPI_STATUS 8 +#define TINY_SPI_CONTROL 12 +#define TINY_SPI_BAUD 16 + +#define TINY_SPI_STATUS_TXE 0x1 +#define TINY_SPI_STATUS_TXR 0x2 + +struct tiny_spi { + /* bitbang has to be first */ + struct spi_bitbang bitbang; + struct completion done; + + void __iomem *base; + int irq; + unsigned int freq; + unsigned int baudwidth; + unsigned int baud; + unsigned int speed_hz; + unsigned int mode; + unsigned int len; + unsigned int txc, rxc; + const u8 *txp; + u8 *rxp; + int gpio_cs_count; + int *gpio_cs; +}; + +static inline struct tiny_spi *tiny_spi_to_hw(struct spi_device *sdev) +{ + return spi_master_get_devdata(sdev->master); +} + +static unsigned int tiny_spi_baud(struct spi_device *spi, unsigned int hz) +{ + struct tiny_spi *hw = tiny_spi_to_hw(spi); + + return min(DIV_ROUND_UP(hw->freq, hz * 2), (1U << hw->baudwidth)) - 1; +} + +static void tiny_spi_chipselect(struct spi_device *spi, int is_active) +{ + struct tiny_spi *hw = tiny_spi_to_hw(spi); + + if (hw->gpio_cs_count > 0) { + gpio_set_value(hw->gpio_cs[spi->chip_select], + (spi->mode & SPI_CS_HIGH) ? is_active : !is_active); + } +} + +static int tiny_spi_setup_transfer(struct spi_device *spi, + struct spi_transfer *t) +{ + struct tiny_spi *hw = tiny_spi_to_hw(spi); + unsigned int baud = hw->baud; + + if (t) { + if (t->speed_hz && t->speed_hz != hw->speed_hz) + baud = tiny_spi_baud(spi, t->speed_hz); + } + writel(baud, hw->base + TINY_SPI_BAUD); + writel(hw->mode, hw->base + TINY_SPI_CONTROL); + return 0; +} + +static int tiny_spi_setup(struct spi_device *spi) +{ + struct tiny_spi *hw = tiny_spi_to_hw(spi); + + if (spi->max_speed_hz != hw->speed_hz) { + hw->speed_hz = spi->max_speed_hz; + hw->baud = tiny_spi_baud(spi, hw->speed_hz); + } + hw->mode = spi->mode & (SPI_CPOL | SPI_CPHA); + return 0; +} + +static inline void tiny_spi_wait_txr(struct tiny_spi *hw) +{ + while (!(readb(hw->base + TINY_SPI_STATUS) & + TINY_SPI_STATUS_TXR)) + cpu_relax(); +} + +static inline void tiny_spi_wait_txe(struct tiny_spi *hw) +{ + while (!(readb(hw->base + TINY_SPI_STATUS) & + TINY_SPI_STATUS_TXE)) + cpu_relax(); +} + +static int tiny_spi_txrx_bufs(struct spi_device *spi, struct spi_transfer *t) +{ + struct tiny_spi *hw = tiny_spi_to_hw(spi); + const u8 *txp = t->tx_buf; + u8 *rxp = t->rx_buf; + unsigned int i; + + if (hw->irq >= 0) { + /* use interrupt driven data transfer */ + hw->len = t->len; + hw->txp = t->tx_buf; + hw->rxp = t->rx_buf; + hw->txc = 0; + hw->rxc = 0; + + /* send the first byte */ + if (t->len > 1) { + writeb(hw->txp ? *hw->txp++ : 0, + hw->base + TINY_SPI_TXDATA); + hw->txc++; + writeb(hw->txp ? *hw->txp++ : 0, + hw->base + TINY_SPI_TXDATA); + hw->txc++; + writeb(TINY_SPI_STATUS_TXR, hw->base + TINY_SPI_STATUS); + } else { + writeb(hw->txp ? *hw->txp++ : 0, + hw->base + TINY_SPI_TXDATA); + hw->txc++; + writeb(TINY_SPI_STATUS_TXE, hw->base + TINY_SPI_STATUS); + } + + wait_for_completion(&hw->done); + } else { + /* we need to tighten the transfer loop */ + writeb(txp ? *txp++ : 0, hw->base + TINY_SPI_TXDATA); + for (i = 1; i < t->len; i++) { + writeb(txp ? *txp++ : 0, hw->base + TINY_SPI_TXDATA); + + if (rxp || (i != t->len - 1)) + tiny_spi_wait_txr(hw); + if (rxp) + *rxp++ = readb(hw->base + TINY_SPI_TXDATA); + } + tiny_spi_wait_txe(hw); + if (rxp) + *rxp++ = readb(hw->base + TINY_SPI_RXDATA); + } + + return t->len; +} + +static irqreturn_t tiny_spi_irq(int irq, void *dev) +{ + struct tiny_spi *hw = dev; + + writeb(0, hw->base + TINY_SPI_STATUS); + if (hw->rxc + 1 == hw->len) { + if (hw->rxp) + *hw->rxp++ = readb(hw->base + TINY_SPI_RXDATA); + hw->rxc++; + complete(&hw->done); + } else { + if (hw->rxp) + *hw->rxp++ = readb(hw->base + TINY_SPI_TXDATA); + hw->rxc++; + if (hw->txc < hw->len) { + writeb(hw->txp ? *hw->txp++ : 0, + hw->base + TINY_SPI_TXDATA); + hw->txc++; + writeb(TINY_SPI_STATUS_TXR, + hw->base + TINY_SPI_STATUS); + } else { + writeb(TINY_SPI_STATUS_TXE, + hw->base + TINY_SPI_STATUS); + } + } + return IRQ_HANDLED; +} + +#ifdef CONFIG_OF +#include <linux/of_gpio.h> + +static int tiny_spi_of_probe(struct platform_device *pdev) +{ + struct tiny_spi *hw = platform_get_drvdata(pdev); + struct device_node *np = pdev->dev.of_node; + unsigned int i; + const __be32 *val; + int len; + + if (!np) + return 0; + hw->gpio_cs_count = of_gpio_count(np); + if (hw->gpio_cs_count > 0) { + hw->gpio_cs = devm_kzalloc(&pdev->dev, + hw->gpio_cs_count * sizeof(unsigned int), + GFP_KERNEL); + if (!hw->gpio_cs) + return -ENOMEM; + } + for (i = 0; i < hw->gpio_cs_count; i++) { + hw->gpio_cs[i] = of_get_gpio_flags(np, i, NULL); + if (hw->gpio_cs[i] < 0) + return -ENODEV; + } + hw->bitbang.master->dev.of_node = pdev->dev.of_node; + val = of_get_property(pdev->dev.of_node, + "clock-frequency", &len); + if (val && len >= sizeof(__be32)) + hw->freq = be32_to_cpup(val); + val = of_get_property(pdev->dev.of_node, "baud-width", &len); + if (val && len >= sizeof(__be32)) + hw->baudwidth = be32_to_cpup(val); + return 0; +} +#else /* !CONFIG_OF */ +static int tiny_spi_of_probe(struct platform_device *pdev) +{ + return 0; +} +#endif /* CONFIG_OF */ + +static int tiny_spi_probe(struct platform_device *pdev) +{ + struct tiny_spi_platform_data *platp = dev_get_platdata(&pdev->dev); + struct tiny_spi *hw; + struct spi_master *master; + struct resource *res; + unsigned int i; + int err = -ENODEV; + + master = spi_alloc_master(&pdev->dev, sizeof(struct tiny_spi)); + if (!master) + return err; + + /* setup the master state. */ + master->bus_num = pdev->id; + master->num_chipselect = 255; + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH; + master->setup = tiny_spi_setup; + + hw = spi_master_get_devdata(master); + platform_set_drvdata(pdev, hw); + + /* setup the state for the bitbang driver */ + hw->bitbang.master = master; + hw->bitbang.setup_transfer = tiny_spi_setup_transfer; + hw->bitbang.chipselect = tiny_spi_chipselect; + hw->bitbang.txrx_bufs = tiny_spi_txrx_bufs; + + /* find and map our resources */ + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + hw->base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(hw->base)) { + err = PTR_ERR(hw->base); + goto exit; + } + /* irq is optional */ + hw->irq = platform_get_irq(pdev, 0); + if (hw->irq >= 0) { + init_completion(&hw->done); + err = devm_request_irq(&pdev->dev, hw->irq, tiny_spi_irq, 0, + pdev->name, hw); + if (err) + goto exit; + } + /* find platform data */ + if (platp) { + hw->gpio_cs_count = platp->gpio_cs_count; + hw->gpio_cs = platp->gpio_cs; + if (platp->gpio_cs_count && !platp->gpio_cs) { + err = -EBUSY; + goto exit; + } + hw->freq = platp->freq; + hw->baudwidth = platp->baudwidth; + } else { + err = tiny_spi_of_probe(pdev); + if (err) + goto exit; + } + for (i = 0; i < hw->gpio_cs_count; i++) { + err = gpio_request(hw->gpio_cs[i], dev_name(&pdev->dev)); + if (err) + goto exit_gpio; + gpio_direction_output(hw->gpio_cs[i], 1); + } + hw->bitbang.master->num_chipselect = max(1, hw->gpio_cs_count); + + /* register our spi controller */ + err = spi_bitbang_start(&hw->bitbang); + if (err) + goto exit; + dev_info(&pdev->dev, "base %p, irq %d\n", hw->base, hw->irq); + + return 0; + +exit_gpio: + while (i-- > 0) + gpio_free(hw->gpio_cs[i]); +exit: + spi_master_put(master); + return err; +} + +static int tiny_spi_remove(struct platform_device *pdev) +{ + struct tiny_spi *hw = platform_get_drvdata(pdev); + struct spi_master *master = hw->bitbang.master; + unsigned int i; + + spi_bitbang_stop(&hw->bitbang); + for (i = 0; i < hw->gpio_cs_count; i++) + gpio_free(hw->gpio_cs[i]); + spi_master_put(master); + return 0; +} + +#ifdef CONFIG_OF +static const struct of_device_id tiny_spi_match[] = { + { .compatible = "opencores,tiny-spi-rtlsvn2", }, + {}, +}; +MODULE_DEVICE_TABLE(of, tiny_spi_match); +#endif /* CONFIG_OF */ + +static struct platform_driver tiny_spi_driver = { + .probe = tiny_spi_probe, + .remove = tiny_spi_remove, + .driver = { + .name = DRV_NAME, + .pm = NULL, + .of_match_table = of_match_ptr(tiny_spi_match), + }, +}; +module_platform_driver(tiny_spi_driver); + +MODULE_DESCRIPTION("OpenCores tiny SPI driver"); +MODULE_AUTHOR("Thomas Chou <thomas@wytron.com.tw>"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:" DRV_NAME); diff --git a/drivers/spi/spi-octeon.c b/drivers/spi/spi-octeon.c new file mode 100644 index 000000000..e99d6a93d --- /dev/null +++ b/drivers/spi/spi-octeon.c @@ -0,0 +1,260 @@ +/* + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + * Copyright (C) 2011, 2012 Cavium, Inc. + */ + +#include <linux/platform_device.h> +#include <linux/interrupt.h> +#include <linux/spi/spi.h> +#include <linux/module.h> +#include <linux/delay.h> +#include <linux/io.h> +#include <linux/of.h> + +#include <asm/octeon/octeon.h> +#include <asm/octeon/cvmx-mpi-defs.h> + +#define OCTEON_SPI_CFG 0 +#define OCTEON_SPI_STS 0x08 +#define OCTEON_SPI_TX 0x10 +#define OCTEON_SPI_DAT0 0x80 + +#define OCTEON_SPI_MAX_BYTES 9 + +#define OCTEON_SPI_MAX_CLOCK_HZ 16000000 + +struct octeon_spi { + u64 register_base; + u64 last_cfg; + u64 cs_enax; +}; + +static void octeon_spi_wait_ready(struct octeon_spi *p) +{ + union cvmx_mpi_sts mpi_sts; + unsigned int loops = 0; + + do { + if (loops++) + __delay(500); + mpi_sts.u64 = cvmx_read_csr(p->register_base + OCTEON_SPI_STS); + } while (mpi_sts.s.busy); +} + +static int octeon_spi_do_transfer(struct octeon_spi *p, + struct spi_message *msg, + struct spi_transfer *xfer, + bool last_xfer) +{ + struct spi_device *spi = msg->spi; + union cvmx_mpi_cfg mpi_cfg; + union cvmx_mpi_tx mpi_tx; + unsigned int clkdiv; + unsigned int speed_hz; + int mode; + bool cpha, cpol; + const u8 *tx_buf; + u8 *rx_buf; + int len; + int i; + + mode = spi->mode; + cpha = mode & SPI_CPHA; + cpol = mode & SPI_CPOL; + + speed_hz = xfer->speed_hz ? : spi->max_speed_hz; + + clkdiv = octeon_get_io_clock_rate() / (2 * speed_hz); + + mpi_cfg.u64 = 0; + + mpi_cfg.s.clkdiv = clkdiv; + mpi_cfg.s.cshi = (mode & SPI_CS_HIGH) ? 1 : 0; + mpi_cfg.s.lsbfirst = (mode & SPI_LSB_FIRST) ? 1 : 0; + mpi_cfg.s.wireor = (mode & SPI_3WIRE) ? 1 : 0; + mpi_cfg.s.idlelo = cpha != cpol; + mpi_cfg.s.cslate = cpha ? 1 : 0; + mpi_cfg.s.enable = 1; + + if (spi->chip_select < 4) + p->cs_enax |= 1ull << (12 + spi->chip_select); + mpi_cfg.u64 |= p->cs_enax; + + if (mpi_cfg.u64 != p->last_cfg) { + p->last_cfg = mpi_cfg.u64; + cvmx_write_csr(p->register_base + OCTEON_SPI_CFG, mpi_cfg.u64); + } + tx_buf = xfer->tx_buf; + rx_buf = xfer->rx_buf; + len = xfer->len; + while (len > OCTEON_SPI_MAX_BYTES) { + for (i = 0; i < OCTEON_SPI_MAX_BYTES; i++) { + u8 d; + if (tx_buf) + d = *tx_buf++; + else + d = 0; + cvmx_write_csr(p->register_base + OCTEON_SPI_DAT0 + (8 * i), d); + } + mpi_tx.u64 = 0; + mpi_tx.s.csid = spi->chip_select; + mpi_tx.s.leavecs = 1; + mpi_tx.s.txnum = tx_buf ? OCTEON_SPI_MAX_BYTES : 0; + mpi_tx.s.totnum = OCTEON_SPI_MAX_BYTES; + cvmx_write_csr(p->register_base + OCTEON_SPI_TX, mpi_tx.u64); + + octeon_spi_wait_ready(p); + if (rx_buf) + for (i = 0; i < OCTEON_SPI_MAX_BYTES; i++) { + u64 v = cvmx_read_csr(p->register_base + OCTEON_SPI_DAT0 + (8 * i)); + *rx_buf++ = (u8)v; + } + len -= OCTEON_SPI_MAX_BYTES; + } + + for (i = 0; i < len; i++) { + u8 d; + if (tx_buf) + d = *tx_buf++; + else + d = 0; + cvmx_write_csr(p->register_base + OCTEON_SPI_DAT0 + (8 * i), d); + } + + mpi_tx.u64 = 0; + mpi_tx.s.csid = spi->chip_select; + if (last_xfer) + mpi_tx.s.leavecs = xfer->cs_change; + else + mpi_tx.s.leavecs = !xfer->cs_change; + mpi_tx.s.txnum = tx_buf ? len : 0; + mpi_tx.s.totnum = len; + cvmx_write_csr(p->register_base + OCTEON_SPI_TX, mpi_tx.u64); + + octeon_spi_wait_ready(p); + if (rx_buf) + for (i = 0; i < len; i++) { + u64 v = cvmx_read_csr(p->register_base + OCTEON_SPI_DAT0 + (8 * i)); + *rx_buf++ = (u8)v; + } + + if (xfer->delay_usecs) + udelay(xfer->delay_usecs); + + return xfer->len; +} + +static int octeon_spi_transfer_one_message(struct spi_master *master, + struct spi_message *msg) +{ + struct octeon_spi *p = spi_master_get_devdata(master); + unsigned int total_len = 0; + int status = 0; + struct spi_transfer *xfer; + + list_for_each_entry(xfer, &msg->transfers, transfer_list) { + bool last_xfer = list_is_last(&xfer->transfer_list, + &msg->transfers); + int r = octeon_spi_do_transfer(p, msg, xfer, last_xfer); + if (r < 0) { + status = r; + goto err; + } + total_len += r; + } +err: + msg->status = status; + msg->actual_length = total_len; + spi_finalize_current_message(master); + return status; +} + +static int octeon_spi_probe(struct platform_device *pdev) +{ + struct resource *res_mem; + struct spi_master *master; + struct octeon_spi *p; + int err = -ENOENT; + + master = spi_alloc_master(&pdev->dev, sizeof(struct octeon_spi)); + if (!master) + return -ENOMEM; + p = spi_master_get_devdata(master); + platform_set_drvdata(pdev, master); + + res_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); + + if (res_mem == NULL) { + dev_err(&pdev->dev, "found no memory resource\n"); + err = -ENXIO; + goto fail; + } + if (!devm_request_mem_region(&pdev->dev, res_mem->start, + resource_size(res_mem), res_mem->name)) { + dev_err(&pdev->dev, "request_mem_region failed\n"); + goto fail; + } + p->register_base = (u64)devm_ioremap(&pdev->dev, res_mem->start, + resource_size(res_mem)); + + master->num_chipselect = 4; + master->mode_bits = SPI_CPHA | + SPI_CPOL | + SPI_CS_HIGH | + SPI_LSB_FIRST | + SPI_3WIRE; + + master->transfer_one_message = octeon_spi_transfer_one_message; + master->bits_per_word_mask = SPI_BPW_MASK(8); + master->max_speed_hz = OCTEON_SPI_MAX_CLOCK_HZ; + + master->dev.of_node = pdev->dev.of_node; + err = devm_spi_register_master(&pdev->dev, master); + if (err) { + dev_err(&pdev->dev, "register master failed: %d\n", err); + goto fail; + } + + dev_info(&pdev->dev, "OCTEON SPI bus driver\n"); + + return 0; +fail: + spi_master_put(master); + return err; +} + +static int octeon_spi_remove(struct platform_device *pdev) +{ + struct spi_master *master = platform_get_drvdata(pdev); + struct octeon_spi *p = spi_master_get_devdata(master); + u64 register_base = p->register_base; + + /* Clear the CSENA* and put everything in a known state. */ + cvmx_write_csr(register_base + OCTEON_SPI_CFG, 0); + + return 0; +} + +static const struct of_device_id octeon_spi_match[] = { + { .compatible = "cavium,octeon-3010-spi", }, + {}, +}; +MODULE_DEVICE_TABLE(of, octeon_spi_match); + +static struct platform_driver octeon_spi_driver = { + .driver = { + .name = "spi-octeon", + .of_match_table = octeon_spi_match, + }, + .probe = octeon_spi_probe, + .remove = octeon_spi_remove, +}; + +module_platform_driver(octeon_spi_driver); + +MODULE_DESCRIPTION("Cavium, Inc. OCTEON SPI bus driver"); +MODULE_AUTHOR("David Daney"); +MODULE_LICENSE("GPL"); diff --git a/drivers/spi/spi-omap-100k.c b/drivers/spi/spi-omap-100k.c new file mode 100644 index 000000000..35b332dac --- /dev/null +++ b/drivers/spi/spi-omap-100k.c @@ -0,0 +1,512 @@ +/* + * OMAP7xx SPI 100k controller driver + * Author: Fabrice Crohas <fcrohas@gmail.com> + * from original omap1_mcspi driver + * + * Copyright (C) 2005, 2006 Nokia Corporation + * Author: Samuel Ortiz <samuel.ortiz@nokia.com> and + * Juha Yrj�l� <juha.yrjola@nokia.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/module.h> +#include <linux/device.h> +#include <linux/delay.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/err.h> +#include <linux/clk.h> +#include <linux/io.h> +#include <linux/gpio.h> +#include <linux/slab.h> + +#include <linux/spi/spi.h> + +#define OMAP1_SPI100K_MAX_FREQ 48000000 + +#define ICR_SPITAS (OMAP7XX_ICR_BASE + 0x12) + +#define SPI_SETUP1 0x00 +#define SPI_SETUP2 0x02 +#define SPI_CTRL 0x04 +#define SPI_STATUS 0x06 +#define SPI_TX_LSB 0x08 +#define SPI_TX_MSB 0x0a +#define SPI_RX_LSB 0x0c +#define SPI_RX_MSB 0x0e + +#define SPI_SETUP1_INT_READ_ENABLE (1UL << 5) +#define SPI_SETUP1_INT_WRITE_ENABLE (1UL << 4) +#define SPI_SETUP1_CLOCK_DIVISOR(x) ((x) << 1) +#define SPI_SETUP1_CLOCK_ENABLE (1UL << 0) + +#define SPI_SETUP2_ACTIVE_EDGE_FALLING (0UL << 0) +#define SPI_SETUP2_ACTIVE_EDGE_RISING (1UL << 0) +#define SPI_SETUP2_NEGATIVE_LEVEL (0UL << 5) +#define SPI_SETUP2_POSITIVE_LEVEL (1UL << 5) +#define SPI_SETUP2_LEVEL_TRIGGER (0UL << 10) +#define SPI_SETUP2_EDGE_TRIGGER (1UL << 10) + +#define SPI_CTRL_SEN(x) ((x) << 7) +#define SPI_CTRL_WORD_SIZE(x) (((x) - 1) << 2) +#define SPI_CTRL_WR (1UL << 1) +#define SPI_CTRL_RD (1UL << 0) + +#define SPI_STATUS_WE (1UL << 1) +#define SPI_STATUS_RD (1UL << 0) + +/* use PIO for small transfers, avoiding DMA setup/teardown overhead and + * cache operations; better heuristics consider wordsize and bitrate. + */ +#define DMA_MIN_BYTES 8 + +#define SPI_RUNNING 0 +#define SPI_SHUTDOWN 1 + +struct omap1_spi100k { + struct clk *ick; + struct clk *fck; + + /* Virtual base address of the controller */ + void __iomem *base; +}; + +struct omap1_spi100k_cs { + void __iomem *base; + int word_len; +}; + +static void spi100k_enable_clock(struct spi_master *master) +{ + unsigned int val; + struct omap1_spi100k *spi100k = spi_master_get_devdata(master); + + /* enable SPI */ + val = readw(spi100k->base + SPI_SETUP1); + val |= SPI_SETUP1_CLOCK_ENABLE; + writew(val, spi100k->base + SPI_SETUP1); +} + +static void spi100k_disable_clock(struct spi_master *master) +{ + unsigned int val; + struct omap1_spi100k *spi100k = spi_master_get_devdata(master); + + /* disable SPI */ + val = readw(spi100k->base + SPI_SETUP1); + val &= ~SPI_SETUP1_CLOCK_ENABLE; + writew(val, spi100k->base + SPI_SETUP1); +} + +static void spi100k_write_data(struct spi_master *master, int len, int data) +{ + struct omap1_spi100k *spi100k = spi_master_get_devdata(master); + + /* write 16-bit word, shifting 8-bit data if necessary */ + if (len <= 8) { + data <<= 8; + len = 16; + } + + spi100k_enable_clock(master); + writew(data , spi100k->base + SPI_TX_MSB); + + writew(SPI_CTRL_SEN(0) | + SPI_CTRL_WORD_SIZE(len) | + SPI_CTRL_WR, + spi100k->base + SPI_CTRL); + + /* Wait for bit ack send change */ + while ((readw(spi100k->base + SPI_STATUS) & SPI_STATUS_WE) != SPI_STATUS_WE) + ; + udelay(1000); + + spi100k_disable_clock(master); +} + +static int spi100k_read_data(struct spi_master *master, int len) +{ + int dataH, dataL; + struct omap1_spi100k *spi100k = spi_master_get_devdata(master); + + /* Always do at least 16 bits */ + if (len <= 8) + len = 16; + + spi100k_enable_clock(master); + writew(SPI_CTRL_SEN(0) | + SPI_CTRL_WORD_SIZE(len) | + SPI_CTRL_RD, + spi100k->base + SPI_CTRL); + + while ((readw(spi100k->base + SPI_STATUS) & SPI_STATUS_RD) != SPI_STATUS_RD) + ; + udelay(1000); + + dataL = readw(spi100k->base + SPI_RX_LSB); + dataH = readw(spi100k->base + SPI_RX_MSB); + spi100k_disable_clock(master); + + return dataL; +} + +static void spi100k_open(struct spi_master *master) +{ + /* get control of SPI */ + struct omap1_spi100k *spi100k = spi_master_get_devdata(master); + + writew(SPI_SETUP1_INT_READ_ENABLE | + SPI_SETUP1_INT_WRITE_ENABLE | + SPI_SETUP1_CLOCK_DIVISOR(0), spi100k->base + SPI_SETUP1); + + /* configure clock and interrupts */ + writew(SPI_SETUP2_ACTIVE_EDGE_FALLING | + SPI_SETUP2_NEGATIVE_LEVEL | + SPI_SETUP2_LEVEL_TRIGGER, spi100k->base + SPI_SETUP2); +} + +static void omap1_spi100k_force_cs(struct omap1_spi100k *spi100k, int enable) +{ + if (enable) + writew(0x05fc, spi100k->base + SPI_CTRL); + else + writew(0x05fd, spi100k->base + SPI_CTRL); +} + +static unsigned +omap1_spi100k_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer) +{ + struct omap1_spi100k_cs *cs = spi->controller_state; + unsigned int count, c; + int word_len; + + count = xfer->len; + c = count; + word_len = cs->word_len; + + if (word_len <= 8) { + u8 *rx; + const u8 *tx; + + rx = xfer->rx_buf; + tx = xfer->tx_buf; + do { + c -= 1; + if (xfer->tx_buf != NULL) + spi100k_write_data(spi->master, word_len, *tx++); + if (xfer->rx_buf != NULL) + *rx++ = spi100k_read_data(spi->master, word_len); + } while (c); + } else if (word_len <= 16) { + u16 *rx; + const u16 *tx; + + rx = xfer->rx_buf; + tx = xfer->tx_buf; + do { + c -= 2; + if (xfer->tx_buf != NULL) + spi100k_write_data(spi->master, word_len, *tx++); + if (xfer->rx_buf != NULL) + *rx++ = spi100k_read_data(spi->master, word_len); + } while (c); + } else if (word_len <= 32) { + u32 *rx; + const u32 *tx; + + rx = xfer->rx_buf; + tx = xfer->tx_buf; + do { + c -= 4; + if (xfer->tx_buf != NULL) + spi100k_write_data(spi->master, word_len, *tx); + if (xfer->rx_buf != NULL) + *rx = spi100k_read_data(spi->master, word_len); + } while (c); + } + return count - c; +} + +/* called only when no transfer is active to this device */ +static int omap1_spi100k_setup_transfer(struct spi_device *spi, + struct spi_transfer *t) +{ + struct omap1_spi100k *spi100k = spi_master_get_devdata(spi->master); + struct omap1_spi100k_cs *cs = spi->controller_state; + u8 word_len = spi->bits_per_word; + + if (t != NULL && t->bits_per_word) + word_len = t->bits_per_word; + if (!word_len) + word_len = 8; + + if (spi->bits_per_word > 32) + return -EINVAL; + cs->word_len = word_len; + + /* SPI init before transfer */ + writew(0x3e , spi100k->base + SPI_SETUP1); + writew(0x00 , spi100k->base + SPI_STATUS); + writew(0x3e , spi100k->base + SPI_CTRL); + + return 0; +} + +/* the spi->mode bits understood by this driver: */ +#define MODEBITS (SPI_CPOL | SPI_CPHA | SPI_CS_HIGH) + +static int omap1_spi100k_setup(struct spi_device *spi) +{ + int ret; + struct omap1_spi100k *spi100k; + struct omap1_spi100k_cs *cs = spi->controller_state; + + spi100k = spi_master_get_devdata(spi->master); + + if (!cs) { + cs = devm_kzalloc(&spi->dev, sizeof(*cs), GFP_KERNEL); + if (!cs) + return -ENOMEM; + cs->base = spi100k->base + spi->chip_select * 0x14; + spi->controller_state = cs; + } + + spi100k_open(spi->master); + + clk_prepare_enable(spi100k->ick); + clk_prepare_enable(spi100k->fck); + + ret = omap1_spi100k_setup_transfer(spi, NULL); + + clk_disable_unprepare(spi100k->ick); + clk_disable_unprepare(spi100k->fck); + + return ret; +} + +static int omap1_spi100k_transfer_one_message(struct spi_master *master, + struct spi_message *m) +{ + struct omap1_spi100k *spi100k = spi_master_get_devdata(master); + struct spi_device *spi = m->spi; + struct spi_transfer *t = NULL; + int cs_active = 0; + int par_override = 0; + int status = 0; + + list_for_each_entry(t, &m->transfers, transfer_list) { + if (t->tx_buf == NULL && t->rx_buf == NULL && t->len) { + status = -EINVAL; + break; + } + if (par_override || t->speed_hz || t->bits_per_word) { + par_override = 1; + status = omap1_spi100k_setup_transfer(spi, t); + if (status < 0) + break; + if (!t->speed_hz && !t->bits_per_word) + par_override = 0; + } + + if (!cs_active) { + omap1_spi100k_force_cs(spi100k, 1); + cs_active = 1; + } + + if (t->len) { + unsigned count; + + count = omap1_spi100k_txrx_pio(spi, t); + m->actual_length += count; + + if (count != t->len) { + status = -EIO; + break; + } + } + + if (t->delay_usecs) + udelay(t->delay_usecs); + + /* ignore the "leave it on after last xfer" hint */ + + if (t->cs_change) { + omap1_spi100k_force_cs(spi100k, 0); + cs_active = 0; + } + } + + /* Restore defaults if they were overriden */ + if (par_override) { + par_override = 0; + status = omap1_spi100k_setup_transfer(spi, NULL); + } + + if (cs_active) + omap1_spi100k_force_cs(spi100k, 0); + + m->status = status; + + spi_finalize_current_message(master); + + return status; +} + +static int omap1_spi100k_probe(struct platform_device *pdev) +{ + struct spi_master *master; + struct omap1_spi100k *spi100k; + int status = 0; + + if (!pdev->id) + return -EINVAL; + + master = spi_alloc_master(&pdev->dev, sizeof(*spi100k)); + if (master == NULL) { + dev_dbg(&pdev->dev, "master allocation failed\n"); + return -ENOMEM; + } + + if (pdev->id != -1) + master->bus_num = pdev->id; + + master->setup = omap1_spi100k_setup; + master->transfer_one_message = omap1_spi100k_transfer_one_message; + master->num_chipselect = 2; + master->mode_bits = MODEBITS; + master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32); + master->min_speed_hz = OMAP1_SPI100K_MAX_FREQ/(1<<16); + master->max_speed_hz = OMAP1_SPI100K_MAX_FREQ; + master->auto_runtime_pm = true; + + spi100k = spi_master_get_devdata(master); + + /* + * The memory region base address is taken as the platform_data. + * You should allocate this with ioremap() before initializing + * the SPI. + */ + spi100k->base = (void __iomem *)dev_get_platdata(&pdev->dev); + + spi100k->ick = devm_clk_get(&pdev->dev, "ick"); + if (IS_ERR(spi100k->ick)) { + dev_dbg(&pdev->dev, "can't get spi100k_ick\n"); + status = PTR_ERR(spi100k->ick); + goto err; + } + + spi100k->fck = devm_clk_get(&pdev->dev, "fck"); + if (IS_ERR(spi100k->fck)) { + dev_dbg(&pdev->dev, "can't get spi100k_fck\n"); + status = PTR_ERR(spi100k->fck); + goto err; + } + + status = clk_prepare_enable(spi100k->ick); + if (status != 0) { + dev_err(&pdev->dev, "failed to enable ick: %d\n", status); + goto err; + } + + status = clk_prepare_enable(spi100k->fck); + if (status != 0) { + dev_err(&pdev->dev, "failed to enable fck: %d\n", status); + goto err_ick; + } + + pm_runtime_enable(&pdev->dev); + pm_runtime_set_active(&pdev->dev); + + status = devm_spi_register_master(&pdev->dev, master); + if (status < 0) + goto err_fck; + + return status; + +err_fck: + clk_disable_unprepare(spi100k->fck); +err_ick: + clk_disable_unprepare(spi100k->ick); +err: + spi_master_put(master); + return status; +} + +static int omap1_spi100k_remove(struct platform_device *pdev) +{ + struct spi_master *master = spi_master_get(platform_get_drvdata(pdev)); + struct omap1_spi100k *spi100k = spi_master_get_devdata(master); + + pm_runtime_disable(&pdev->dev); + + clk_disable_unprepare(spi100k->fck); + clk_disable_unprepare(spi100k->ick); + + return 0; +} + +#ifdef CONFIG_PM +static int omap1_spi100k_runtime_suspend(struct device *dev) +{ + struct spi_master *master = spi_master_get(dev_get_drvdata(dev)); + struct omap1_spi100k *spi100k = spi_master_get_devdata(master); + + clk_disable_unprepare(spi100k->ick); + clk_disable_unprepare(spi100k->fck); + + return 0; +} + +static int omap1_spi100k_runtime_resume(struct device *dev) +{ + struct spi_master *master = spi_master_get(dev_get_drvdata(dev)); + struct omap1_spi100k *spi100k = spi_master_get_devdata(master); + int ret; + + ret = clk_prepare_enable(spi100k->ick); + if (ret != 0) { + dev_err(dev, "Failed to enable ick: %d\n", ret); + return ret; + } + + ret = clk_prepare_enable(spi100k->fck); + if (ret != 0) { + dev_err(dev, "Failed to enable fck: %d\n", ret); + clk_disable_unprepare(spi100k->ick); + return ret; + } + + return 0; +} +#endif + +static const struct dev_pm_ops omap1_spi100k_pm = { + SET_RUNTIME_PM_OPS(omap1_spi100k_runtime_suspend, + omap1_spi100k_runtime_resume, NULL) +}; + +static struct platform_driver omap1_spi100k_driver = { + .driver = { + .name = "omap1_spi100k", + .pm = &omap1_spi100k_pm, + }, + .probe = omap1_spi100k_probe, + .remove = omap1_spi100k_remove, +}; + +module_platform_driver(omap1_spi100k_driver); + +MODULE_DESCRIPTION("OMAP7xx SPI 100k controller driver"); +MODULE_AUTHOR("Fabrice Crohas <fcrohas@gmail.com>"); +MODULE_LICENSE("GPL"); diff --git a/drivers/spi/spi-omap-uwire.c b/drivers/spi/spi-omap-uwire.c new file mode 100644 index 000000000..55576db31 --- /dev/null +++ b/drivers/spi/spi-omap-uwire.c @@ -0,0 +1,561 @@ +/* + * MicroWire interface driver for OMAP + * + * Copyright 2003 MontaVista Software Inc. <source@mvista.com> + * + * Ported to 2.6 OMAP uwire interface. + * Copyright (C) 2004 Texas Instruments. + * + * Generalization patches by Juha Yrjola <juha.yrjola@nokia.com> + * + * Copyright (C) 2005 David Brownell (ported to 2.6 SPI interface) + * Copyright (C) 2006 Nokia + * + * Many updates by Imre Deak <imre.deak@nokia.com> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + * + * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED + * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF + * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON + * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/delay.h> +#include <linux/platform_device.h> +#include <linux/interrupt.h> +#include <linux/err.h> +#include <linux/clk.h> +#include <linux/slab.h> +#include <linux/device.h> + +#include <linux/spi/spi.h> +#include <linux/spi/spi_bitbang.h> +#include <linux/module.h> +#include <linux/io.h> + +#include <mach/hardware.h> +#include <asm/mach-types.h> + +#include <mach/mux.h> + +#include <mach/omap7xx.h> /* OMAP7XX_IO_CONF registers */ + + +/* FIXME address is now a platform device resource, + * and irqs should show there too... + */ +#define UWIRE_BASE_PHYS 0xFFFB3000 + +/* uWire Registers: */ +#define UWIRE_IO_SIZE 0x20 +#define UWIRE_TDR 0x00 +#define UWIRE_RDR 0x00 +#define UWIRE_CSR 0x01 +#define UWIRE_SR1 0x02 +#define UWIRE_SR2 0x03 +#define UWIRE_SR3 0x04 +#define UWIRE_SR4 0x05 +#define UWIRE_SR5 0x06 + +/* CSR bits */ +#define RDRB (1 << 15) +#define CSRB (1 << 14) +#define START (1 << 13) +#define CS_CMD (1 << 12) + +/* SR1 or SR2 bits */ +#define UWIRE_READ_FALLING_EDGE 0x0001 +#define UWIRE_READ_RISING_EDGE 0x0000 +#define UWIRE_WRITE_FALLING_EDGE 0x0000 +#define UWIRE_WRITE_RISING_EDGE 0x0002 +#define UWIRE_CS_ACTIVE_LOW 0x0000 +#define UWIRE_CS_ACTIVE_HIGH 0x0004 +#define UWIRE_FREQ_DIV_2 0x0000 +#define UWIRE_FREQ_DIV_4 0x0008 +#define UWIRE_FREQ_DIV_8 0x0010 +#define UWIRE_CHK_READY 0x0020 +#define UWIRE_CLK_INVERTED 0x0040 + + +struct uwire_spi { + struct spi_bitbang bitbang; + struct clk *ck; +}; + +struct uwire_state { + unsigned div1_idx; +}; + +/* REVISIT compile time constant for idx_shift? */ +/* + * Or, put it in a structure which is used throughout the driver; + * that avoids having to issue two loads for each bit of static data. + */ +static unsigned int uwire_idx_shift; +static void __iomem *uwire_base; + +static inline void uwire_write_reg(int idx, u16 val) +{ + __raw_writew(val, uwire_base + (idx << uwire_idx_shift)); +} + +static inline u16 uwire_read_reg(int idx) +{ + return __raw_readw(uwire_base + (idx << uwire_idx_shift)); +} + +static inline void omap_uwire_configure_mode(u8 cs, unsigned long flags) +{ + u16 w, val = 0; + int shift, reg; + + if (flags & UWIRE_CLK_INVERTED) + val ^= 0x03; + val = flags & 0x3f; + if (cs & 1) + shift = 6; + else + shift = 0; + if (cs <= 1) + reg = UWIRE_SR1; + else + reg = UWIRE_SR2; + + w = uwire_read_reg(reg); + w &= ~(0x3f << shift); + w |= val << shift; + uwire_write_reg(reg, w); +} + +static int wait_uwire_csr_flag(u16 mask, u16 val, int might_not_catch) +{ + u16 w; + int c = 0; + unsigned long max_jiffies = jiffies + HZ; + + for (;;) { + w = uwire_read_reg(UWIRE_CSR); + if ((w & mask) == val) + break; + if (time_after(jiffies, max_jiffies)) { + printk(KERN_ERR "%s: timeout. reg=%#06x " + "mask=%#06x val=%#06x\n", + __func__, w, mask, val); + return -1; + } + c++; + if (might_not_catch && c > 64) + break; + } + return 0; +} + +static void uwire_set_clk1_div(int div1_idx) +{ + u16 w; + + w = uwire_read_reg(UWIRE_SR3); + w &= ~(0x03 << 1); + w |= div1_idx << 1; + uwire_write_reg(UWIRE_SR3, w); +} + +static void uwire_chipselect(struct spi_device *spi, int value) +{ + struct uwire_state *ust = spi->controller_state; + u16 w; + int old_cs; + + + BUG_ON(wait_uwire_csr_flag(CSRB, 0, 0)); + + w = uwire_read_reg(UWIRE_CSR); + old_cs = (w >> 10) & 0x03; + if (value == BITBANG_CS_INACTIVE || old_cs != spi->chip_select) { + /* Deselect this CS, or the previous CS */ + w &= ~CS_CMD; + uwire_write_reg(UWIRE_CSR, w); + } + /* activate specfied chipselect */ + if (value == BITBANG_CS_ACTIVE) { + uwire_set_clk1_div(ust->div1_idx); + /* invert clock? */ + if (spi->mode & SPI_CPOL) + uwire_write_reg(UWIRE_SR4, 1); + else + uwire_write_reg(UWIRE_SR4, 0); + + w = spi->chip_select << 10; + w |= CS_CMD; + uwire_write_reg(UWIRE_CSR, w); + } +} + +static int uwire_txrx(struct spi_device *spi, struct spi_transfer *t) +{ + unsigned len = t->len; + unsigned bits = t->bits_per_word ? : spi->bits_per_word; + unsigned bytes; + u16 val, w; + int status = 0; + + if (!t->tx_buf && !t->rx_buf) + return 0; + + w = spi->chip_select << 10; + w |= CS_CMD; + + if (t->tx_buf) { + const u8 *buf = t->tx_buf; + + /* NOTE: DMA could be used for TX transfers */ + + /* write one or two bytes at a time */ + while (len >= 1) { + /* tx bit 15 is first sent; we byteswap multibyte words + * (msb-first) on the way out from memory. + */ + val = *buf++; + if (bits > 8) { + bytes = 2; + val |= *buf++ << 8; + } else + bytes = 1; + val <<= 16 - bits; + +#ifdef VERBOSE + pr_debug("%s: write-%d =%04x\n", + dev_name(&spi->dev), bits, val); +#endif + if (wait_uwire_csr_flag(CSRB, 0, 0)) + goto eio; + + uwire_write_reg(UWIRE_TDR, val); + + /* start write */ + val = START | w | (bits << 5); + + uwire_write_reg(UWIRE_CSR, val); + len -= bytes; + + /* Wait till write actually starts. + * This is needed with MPU clock 60+ MHz. + * REVISIT: we may not have time to catch it... + */ + if (wait_uwire_csr_flag(CSRB, CSRB, 1)) + goto eio; + + status += bytes; + } + + /* REVISIT: save this for later to get more i/o overlap */ + if (wait_uwire_csr_flag(CSRB, 0, 0)) + goto eio; + + } else if (t->rx_buf) { + u8 *buf = t->rx_buf; + + /* read one or two bytes at a time */ + while (len) { + if (bits > 8) { + bytes = 2; + } else + bytes = 1; + + /* start read */ + val = START | w | (bits << 0); + uwire_write_reg(UWIRE_CSR, val); + len -= bytes; + + /* Wait till read actually starts */ + (void) wait_uwire_csr_flag(CSRB, CSRB, 1); + + if (wait_uwire_csr_flag(RDRB | CSRB, + RDRB, 0)) + goto eio; + + /* rx bit 0 is last received; multibyte words will + * be properly byteswapped on the way to memory. + */ + val = uwire_read_reg(UWIRE_RDR); + val &= (1 << bits) - 1; + *buf++ = (u8) val; + if (bytes == 2) + *buf++ = val >> 8; + status += bytes; +#ifdef VERBOSE + pr_debug("%s: read-%d =%04x\n", + dev_name(&spi->dev), bits, val); +#endif + + } + } + return status; +eio: + return -EIO; +} + +static int uwire_setup_transfer(struct spi_device *spi, struct spi_transfer *t) +{ + struct uwire_state *ust = spi->controller_state; + struct uwire_spi *uwire; + unsigned flags = 0; + unsigned hz; + unsigned long rate; + int div1_idx; + int div1; + int div2; + int status; + + uwire = spi_master_get_devdata(spi->master); + + /* mode 0..3, clock inverted separately; + * standard nCS signaling; + * don't treat DI=high as "not ready" + */ + if (spi->mode & SPI_CS_HIGH) + flags |= UWIRE_CS_ACTIVE_HIGH; + + if (spi->mode & SPI_CPOL) + flags |= UWIRE_CLK_INVERTED; + + switch (spi->mode & (SPI_CPOL | SPI_CPHA)) { + case SPI_MODE_0: + case SPI_MODE_3: + flags |= UWIRE_WRITE_FALLING_EDGE | UWIRE_READ_RISING_EDGE; + break; + case SPI_MODE_1: + case SPI_MODE_2: + flags |= UWIRE_WRITE_RISING_EDGE | UWIRE_READ_FALLING_EDGE; + break; + } + + /* assume it's already enabled */ + rate = clk_get_rate(uwire->ck); + + hz = spi->max_speed_hz; + if (t != NULL && t->speed_hz) + hz = t->speed_hz; + + if (!hz) { + pr_debug("%s: zero speed?\n", dev_name(&spi->dev)); + status = -EINVAL; + goto done; + } + + /* F_INT = mpu_xor_clk / DIV1 */ + for (div1_idx = 0; div1_idx < 4; div1_idx++) { + switch (div1_idx) { + case 0: + div1 = 2; + break; + case 1: + div1 = 4; + break; + case 2: + div1 = 7; + break; + default: + case 3: + div1 = 10; + break; + } + div2 = (rate / div1 + hz - 1) / hz; + if (div2 <= 8) + break; + } + if (div1_idx == 4) { + pr_debug("%s: lowest clock %ld, need %d\n", + dev_name(&spi->dev), rate / 10 / 8, hz); + status = -EDOM; + goto done; + } + + /* we have to cache this and reset in uwire_chipselect as this is a + * global parameter and another uwire device can change it under + * us */ + ust->div1_idx = div1_idx; + uwire_set_clk1_div(div1_idx); + + rate /= div1; + + switch (div2) { + case 0: + case 1: + case 2: + flags |= UWIRE_FREQ_DIV_2; + rate /= 2; + break; + case 3: + case 4: + flags |= UWIRE_FREQ_DIV_4; + rate /= 4; + break; + case 5: + case 6: + case 7: + case 8: + flags |= UWIRE_FREQ_DIV_8; + rate /= 8; + break; + } + omap_uwire_configure_mode(spi->chip_select, flags); + pr_debug("%s: uwire flags %02x, armxor %lu KHz, SCK %lu KHz\n", + __func__, flags, + clk_get_rate(uwire->ck) / 1000, + rate / 1000); + status = 0; +done: + return status; +} + +static int uwire_setup(struct spi_device *spi) +{ + struct uwire_state *ust = spi->controller_state; + + if (ust == NULL) { + ust = kzalloc(sizeof(*ust), GFP_KERNEL); + if (ust == NULL) + return -ENOMEM; + spi->controller_state = ust; + } + + return uwire_setup_transfer(spi, NULL); +} + +static void uwire_cleanup(struct spi_device *spi) +{ + kfree(spi->controller_state); +} + +static void uwire_off(struct uwire_spi *uwire) +{ + uwire_write_reg(UWIRE_SR3, 0); + clk_disable(uwire->ck); + spi_master_put(uwire->bitbang.master); +} + +static int uwire_probe(struct platform_device *pdev) +{ + struct spi_master *master; + struct uwire_spi *uwire; + int status; + + master = spi_alloc_master(&pdev->dev, sizeof *uwire); + if (!master) + return -ENODEV; + + uwire = spi_master_get_devdata(master); + + uwire_base = devm_ioremap(&pdev->dev, UWIRE_BASE_PHYS, UWIRE_IO_SIZE); + if (!uwire_base) { + dev_dbg(&pdev->dev, "can't ioremap UWIRE\n"); + spi_master_put(master); + return -ENOMEM; + } + + platform_set_drvdata(pdev, uwire); + + uwire->ck = devm_clk_get(&pdev->dev, "fck"); + if (IS_ERR(uwire->ck)) { + status = PTR_ERR(uwire->ck); + dev_dbg(&pdev->dev, "no functional clock?\n"); + spi_master_put(master); + return status; + } + clk_enable(uwire->ck); + + if (cpu_is_omap7xx()) + uwire_idx_shift = 1; + else + uwire_idx_shift = 2; + + uwire_write_reg(UWIRE_SR3, 1); + + /* the spi->mode bits understood by this driver: */ + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH; + master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 16); + master->flags = SPI_MASTER_HALF_DUPLEX; + + master->bus_num = 2; /* "official" */ + master->num_chipselect = 4; + master->setup = uwire_setup; + master->cleanup = uwire_cleanup; + + uwire->bitbang.master = master; + uwire->bitbang.chipselect = uwire_chipselect; + uwire->bitbang.setup_transfer = uwire_setup_transfer; + uwire->bitbang.txrx_bufs = uwire_txrx; + + status = spi_bitbang_start(&uwire->bitbang); + if (status < 0) { + uwire_off(uwire); + } + return status; +} + +static int uwire_remove(struct platform_device *pdev) +{ + struct uwire_spi *uwire = platform_get_drvdata(pdev); + + // FIXME remove all child devices, somewhere ... + + spi_bitbang_stop(&uwire->bitbang); + uwire_off(uwire); + return 0; +} + +/* work with hotplug and coldplug */ +MODULE_ALIAS("platform:omap_uwire"); + +static struct platform_driver uwire_driver = { + .driver = { + .name = "omap_uwire", + }, + .probe = uwire_probe, + .remove = uwire_remove, + // suspend ... unuse ck + // resume ... use ck +}; + +static int __init omap_uwire_init(void) +{ + /* FIXME move these into the relevant board init code. also, include + * H3 support; it uses tsc2101 like H2 (on a different chipselect). + */ + + if (machine_is_omap_h2()) { + /* defaults: W21 SDO, U18 SDI, V19 SCL */ + omap_cfg_reg(N14_1610_UWIRE_CS0); + omap_cfg_reg(N15_1610_UWIRE_CS1); + } + if (machine_is_omap_perseus2()) { + /* configure pins: MPU_UW_nSCS1, MPU_UW_SDO, MPU_UW_SCLK */ + int val = omap_readl(OMAP7XX_IO_CONF_9) & ~0x00EEE000; + omap_writel(val | 0x00AAA000, OMAP7XX_IO_CONF_9); + } + + return platform_driver_register(&uwire_driver); +} + +static void __exit omap_uwire_exit(void) +{ + platform_driver_unregister(&uwire_driver); +} + +subsys_initcall(omap_uwire_init); +module_exit(omap_uwire_exit); + +MODULE_LICENSE("GPL"); + diff --git a/drivers/spi/spi-omap2-mcspi.c b/drivers/spi/spi-omap2-mcspi.c new file mode 100644 index 000000000..d1a5b9fc3 --- /dev/null +++ b/drivers/spi/spi-omap2-mcspi.c @@ -0,0 +1,1535 @@ +/* + * OMAP2 McSPI controller driver + * + * Copyright (C) 2005, 2006 Nokia Corporation + * Author: Samuel Ortiz <samuel.ortiz@nokia.com> and + * Juha Yrj�l� <juha.yrjola@nokia.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/kernel.h> +#include <linux/interrupt.h> +#include <linux/module.h> +#include <linux/device.h> +#include <linux/delay.h> +#include <linux/dma-mapping.h> +#include <linux/dmaengine.h> +#include <linux/omap-dma.h> +#include <linux/platform_device.h> +#include <linux/err.h> +#include <linux/clk.h> +#include <linux/io.h> +#include <linux/slab.h> +#include <linux/pm_runtime.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/gcd.h> + +#include <linux/spi/spi.h> + +#include <linux/platform_data/spi-omap2-mcspi.h> + +#define OMAP2_MCSPI_MAX_FREQ 48000000 +#define OMAP2_MCSPI_MAX_DIVIDER 4096 +#define OMAP2_MCSPI_MAX_FIFODEPTH 64 +#define OMAP2_MCSPI_MAX_FIFOWCNT 0xFFFF +#define SPI_AUTOSUSPEND_TIMEOUT 2000 + +#define OMAP2_MCSPI_REVISION 0x00 +#define OMAP2_MCSPI_SYSSTATUS 0x14 +#define OMAP2_MCSPI_IRQSTATUS 0x18 +#define OMAP2_MCSPI_IRQENABLE 0x1c +#define OMAP2_MCSPI_WAKEUPENABLE 0x20 +#define OMAP2_MCSPI_SYST 0x24 +#define OMAP2_MCSPI_MODULCTRL 0x28 +#define OMAP2_MCSPI_XFERLEVEL 0x7c + +/* per-channel banks, 0x14 bytes each, first is: */ +#define OMAP2_MCSPI_CHCONF0 0x2c +#define OMAP2_MCSPI_CHSTAT0 0x30 +#define OMAP2_MCSPI_CHCTRL0 0x34 +#define OMAP2_MCSPI_TX0 0x38 +#define OMAP2_MCSPI_RX0 0x3c + +/* per-register bitmasks: */ +#define OMAP2_MCSPI_IRQSTATUS_EOW BIT(17) + +#define OMAP2_MCSPI_MODULCTRL_SINGLE BIT(0) +#define OMAP2_MCSPI_MODULCTRL_MS BIT(2) +#define OMAP2_MCSPI_MODULCTRL_STEST BIT(3) + +#define OMAP2_MCSPI_CHCONF_PHA BIT(0) +#define OMAP2_MCSPI_CHCONF_POL BIT(1) +#define OMAP2_MCSPI_CHCONF_CLKD_MASK (0x0f << 2) +#define OMAP2_MCSPI_CHCONF_EPOL BIT(6) +#define OMAP2_MCSPI_CHCONF_WL_MASK (0x1f << 7) +#define OMAP2_MCSPI_CHCONF_TRM_RX_ONLY BIT(12) +#define OMAP2_MCSPI_CHCONF_TRM_TX_ONLY BIT(13) +#define OMAP2_MCSPI_CHCONF_TRM_MASK (0x03 << 12) +#define OMAP2_MCSPI_CHCONF_DMAW BIT(14) +#define OMAP2_MCSPI_CHCONF_DMAR BIT(15) +#define OMAP2_MCSPI_CHCONF_DPE0 BIT(16) +#define OMAP2_MCSPI_CHCONF_DPE1 BIT(17) +#define OMAP2_MCSPI_CHCONF_IS BIT(18) +#define OMAP2_MCSPI_CHCONF_TURBO BIT(19) +#define OMAP2_MCSPI_CHCONF_FORCE BIT(20) +#define OMAP2_MCSPI_CHCONF_FFET BIT(27) +#define OMAP2_MCSPI_CHCONF_FFER BIT(28) +#define OMAP2_MCSPI_CHCONF_CLKG BIT(29) + +#define OMAP2_MCSPI_CHSTAT_RXS BIT(0) +#define OMAP2_MCSPI_CHSTAT_TXS BIT(1) +#define OMAP2_MCSPI_CHSTAT_EOT BIT(2) +#define OMAP2_MCSPI_CHSTAT_TXFFE BIT(3) + +#define OMAP2_MCSPI_CHCTRL_EN BIT(0) +#define OMAP2_MCSPI_CHCTRL_EXTCLK_MASK (0xff << 8) + +#define OMAP2_MCSPI_WAKEUPENABLE_WKEN BIT(0) + +/* We have 2 DMA channels per CS, one for RX and one for TX */ +struct omap2_mcspi_dma { + struct dma_chan *dma_tx; + struct dma_chan *dma_rx; + + int dma_tx_sync_dev; + int dma_rx_sync_dev; + + struct completion dma_tx_completion; + struct completion dma_rx_completion; + + char dma_rx_ch_name[14]; + char dma_tx_ch_name[14]; +}; + +/* use PIO for small transfers, avoiding DMA setup/teardown overhead and + * cache operations; better heuristics consider wordsize and bitrate. + */ +#define DMA_MIN_BYTES 160 + + +/* + * Used for context save and restore, structure members to be updated whenever + * corresponding registers are modified. + */ +struct omap2_mcspi_regs { + u32 modulctrl; + u32 wakeupenable; + struct list_head cs; +}; + +struct omap2_mcspi { + struct spi_master *master; + /* Virtual base address of the controller */ + void __iomem *base; + unsigned long phys; + /* SPI1 has 4 channels, while SPI2 has 2 */ + struct omap2_mcspi_dma *dma_channels; + struct device *dev; + struct omap2_mcspi_regs ctx; + int fifo_depth; + unsigned int pin_dir:1; +}; + +struct omap2_mcspi_cs { + void __iomem *base; + unsigned long phys; + int word_len; + u16 mode; + struct list_head node; + /* Context save and restore shadow register */ + u32 chconf0, chctrl0; +}; + +static inline void mcspi_write_reg(struct spi_master *master, + int idx, u32 val) +{ + struct omap2_mcspi *mcspi = spi_master_get_devdata(master); + + writel_relaxed(val, mcspi->base + idx); +} + +static inline u32 mcspi_read_reg(struct spi_master *master, int idx) +{ + struct omap2_mcspi *mcspi = spi_master_get_devdata(master); + + return readl_relaxed(mcspi->base + idx); +} + +static inline void mcspi_write_cs_reg(const struct spi_device *spi, + int idx, u32 val) +{ + struct omap2_mcspi_cs *cs = spi->controller_state; + + writel_relaxed(val, cs->base + idx); +} + +static inline u32 mcspi_read_cs_reg(const struct spi_device *spi, int idx) +{ + struct omap2_mcspi_cs *cs = spi->controller_state; + + return readl_relaxed(cs->base + idx); +} + +static inline u32 mcspi_cached_chconf0(const struct spi_device *spi) +{ + struct omap2_mcspi_cs *cs = spi->controller_state; + + return cs->chconf0; +} + +static inline void mcspi_write_chconf0(const struct spi_device *spi, u32 val) +{ + struct omap2_mcspi_cs *cs = spi->controller_state; + + cs->chconf0 = val; + mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCONF0, val); + mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCONF0); +} + +static inline int mcspi_bytes_per_word(int word_len) +{ + if (word_len <= 8) + return 1; + else if (word_len <= 16) + return 2; + else /* word_len <= 32 */ + return 4; +} + +static void omap2_mcspi_set_dma_req(const struct spi_device *spi, + int is_read, int enable) +{ + u32 l, rw; + + l = mcspi_cached_chconf0(spi); + + if (is_read) /* 1 is read, 0 write */ + rw = OMAP2_MCSPI_CHCONF_DMAR; + else + rw = OMAP2_MCSPI_CHCONF_DMAW; + + if (enable) + l |= rw; + else + l &= ~rw; + + mcspi_write_chconf0(spi, l); +} + +static void omap2_mcspi_set_enable(const struct spi_device *spi, int enable) +{ + struct omap2_mcspi_cs *cs = spi->controller_state; + u32 l; + + l = cs->chctrl0; + if (enable) + l |= OMAP2_MCSPI_CHCTRL_EN; + else + l &= ~OMAP2_MCSPI_CHCTRL_EN; + cs->chctrl0 = l; + mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0); + /* Flash post-writes */ + mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCTRL0); +} + +static void omap2_mcspi_force_cs(struct spi_device *spi, int cs_active) +{ + u32 l; + + l = mcspi_cached_chconf0(spi); + if (cs_active) + l |= OMAP2_MCSPI_CHCONF_FORCE; + else + l &= ~OMAP2_MCSPI_CHCONF_FORCE; + + mcspi_write_chconf0(spi, l); +} + +static void omap2_mcspi_set_master_mode(struct spi_master *master) +{ + struct omap2_mcspi *mcspi = spi_master_get_devdata(master); + struct omap2_mcspi_regs *ctx = &mcspi->ctx; + u32 l; + + /* + * Setup when switching from (reset default) slave mode + * to single-channel master mode + */ + l = mcspi_read_reg(master, OMAP2_MCSPI_MODULCTRL); + l &= ~(OMAP2_MCSPI_MODULCTRL_STEST | OMAP2_MCSPI_MODULCTRL_MS); + l |= OMAP2_MCSPI_MODULCTRL_SINGLE; + mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, l); + + ctx->modulctrl = l; +} + +static void omap2_mcspi_set_fifo(const struct spi_device *spi, + struct spi_transfer *t, int enable) +{ + struct spi_master *master = spi->master; + struct omap2_mcspi_cs *cs = spi->controller_state; + struct omap2_mcspi *mcspi; + unsigned int wcnt; + int max_fifo_depth, fifo_depth, bytes_per_word; + u32 chconf, xferlevel; + + mcspi = spi_master_get_devdata(master); + + chconf = mcspi_cached_chconf0(spi); + if (enable) { + bytes_per_word = mcspi_bytes_per_word(cs->word_len); + if (t->len % bytes_per_word != 0) + goto disable_fifo; + + if (t->rx_buf != NULL && t->tx_buf != NULL) + max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH / 2; + else + max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH; + + fifo_depth = gcd(t->len, max_fifo_depth); + if (fifo_depth < 2 || fifo_depth % bytes_per_word != 0) + goto disable_fifo; + + wcnt = t->len / bytes_per_word; + if (wcnt > OMAP2_MCSPI_MAX_FIFOWCNT) + goto disable_fifo; + + xferlevel = wcnt << 16; + if (t->rx_buf != NULL) { + chconf |= OMAP2_MCSPI_CHCONF_FFER; + xferlevel |= (fifo_depth - 1) << 8; + } + if (t->tx_buf != NULL) { + chconf |= OMAP2_MCSPI_CHCONF_FFET; + xferlevel |= fifo_depth - 1; + } + + mcspi_write_reg(master, OMAP2_MCSPI_XFERLEVEL, xferlevel); + mcspi_write_chconf0(spi, chconf); + mcspi->fifo_depth = fifo_depth; + + return; + } + +disable_fifo: + if (t->rx_buf != NULL) + chconf &= ~OMAP2_MCSPI_CHCONF_FFER; + + if (t->tx_buf != NULL) + chconf &= ~OMAP2_MCSPI_CHCONF_FFET; + + mcspi_write_chconf0(spi, chconf); + mcspi->fifo_depth = 0; +} + +static void omap2_mcspi_restore_ctx(struct omap2_mcspi *mcspi) +{ + struct spi_master *spi_cntrl = mcspi->master; + struct omap2_mcspi_regs *ctx = &mcspi->ctx; + struct omap2_mcspi_cs *cs; + + /* McSPI: context restore */ + mcspi_write_reg(spi_cntrl, OMAP2_MCSPI_MODULCTRL, ctx->modulctrl); + mcspi_write_reg(spi_cntrl, OMAP2_MCSPI_WAKEUPENABLE, ctx->wakeupenable); + + list_for_each_entry(cs, &ctx->cs, node) + writel_relaxed(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0); +} + +static int mcspi_wait_for_reg_bit(void __iomem *reg, unsigned long bit) +{ + unsigned long timeout; + + timeout = jiffies + msecs_to_jiffies(1000); + while (!(readl_relaxed(reg) & bit)) { + if (time_after(jiffies, timeout)) { + if (!(readl_relaxed(reg) & bit)) + return -ETIMEDOUT; + else + return 0; + } + cpu_relax(); + } + return 0; +} + +static void omap2_mcspi_rx_callback(void *data) +{ + struct spi_device *spi = data; + struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master); + struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select]; + + /* We must disable the DMA RX request */ + omap2_mcspi_set_dma_req(spi, 1, 0); + + complete(&mcspi_dma->dma_rx_completion); +} + +static void omap2_mcspi_tx_callback(void *data) +{ + struct spi_device *spi = data; + struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master); + struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select]; + + /* We must disable the DMA TX request */ + omap2_mcspi_set_dma_req(spi, 0, 0); + + complete(&mcspi_dma->dma_tx_completion); +} + +static void omap2_mcspi_tx_dma(struct spi_device *spi, + struct spi_transfer *xfer, + struct dma_slave_config cfg) +{ + struct omap2_mcspi *mcspi; + struct omap2_mcspi_dma *mcspi_dma; + unsigned int count; + + mcspi = spi_master_get_devdata(spi->master); + mcspi_dma = &mcspi->dma_channels[spi->chip_select]; + count = xfer->len; + + if (mcspi_dma->dma_tx) { + struct dma_async_tx_descriptor *tx; + struct scatterlist sg; + + dmaengine_slave_config(mcspi_dma->dma_tx, &cfg); + + sg_init_table(&sg, 1); + sg_dma_address(&sg) = xfer->tx_dma; + sg_dma_len(&sg) = xfer->len; + + tx = dmaengine_prep_slave_sg(mcspi_dma->dma_tx, &sg, 1, + DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + if (tx) { + tx->callback = omap2_mcspi_tx_callback; + tx->callback_param = spi; + dmaengine_submit(tx); + } else { + /* FIXME: fall back to PIO? */ + } + } + dma_async_issue_pending(mcspi_dma->dma_tx); + omap2_mcspi_set_dma_req(spi, 0, 1); + +} + +static unsigned +omap2_mcspi_rx_dma(struct spi_device *spi, struct spi_transfer *xfer, + struct dma_slave_config cfg, + unsigned es) +{ + struct omap2_mcspi *mcspi; + struct omap2_mcspi_dma *mcspi_dma; + unsigned int count, dma_count; + u32 l; + int elements = 0; + int word_len, element_count; + struct omap2_mcspi_cs *cs = spi->controller_state; + mcspi = spi_master_get_devdata(spi->master); + mcspi_dma = &mcspi->dma_channels[spi->chip_select]; + count = xfer->len; + dma_count = xfer->len; + + if (mcspi->fifo_depth == 0) + dma_count -= es; + + word_len = cs->word_len; + l = mcspi_cached_chconf0(spi); + + if (word_len <= 8) + element_count = count; + else if (word_len <= 16) + element_count = count >> 1; + else /* word_len <= 32 */ + element_count = count >> 2; + + if (mcspi_dma->dma_rx) { + struct dma_async_tx_descriptor *tx; + struct scatterlist sg; + + dmaengine_slave_config(mcspi_dma->dma_rx, &cfg); + + if ((l & OMAP2_MCSPI_CHCONF_TURBO) && mcspi->fifo_depth == 0) + dma_count -= es; + + sg_init_table(&sg, 1); + sg_dma_address(&sg) = xfer->rx_dma; + sg_dma_len(&sg) = dma_count; + + tx = dmaengine_prep_slave_sg(mcspi_dma->dma_rx, &sg, 1, + DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT | + DMA_CTRL_ACK); + if (tx) { + tx->callback = omap2_mcspi_rx_callback; + tx->callback_param = spi; + dmaengine_submit(tx); + } else { + /* FIXME: fall back to PIO? */ + } + } + + dma_async_issue_pending(mcspi_dma->dma_rx); + omap2_mcspi_set_dma_req(spi, 1, 1); + + wait_for_completion(&mcspi_dma->dma_rx_completion); + dma_unmap_single(mcspi->dev, xfer->rx_dma, count, + DMA_FROM_DEVICE); + + if (mcspi->fifo_depth > 0) + return count; + + omap2_mcspi_set_enable(spi, 0); + + elements = element_count - 1; + + if (l & OMAP2_MCSPI_CHCONF_TURBO) { + elements--; + + if (likely(mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHSTAT0) + & OMAP2_MCSPI_CHSTAT_RXS)) { + u32 w; + + w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0); + if (word_len <= 8) + ((u8 *)xfer->rx_buf)[elements++] = w; + else if (word_len <= 16) + ((u16 *)xfer->rx_buf)[elements++] = w; + else /* word_len <= 32 */ + ((u32 *)xfer->rx_buf)[elements++] = w; + } else { + int bytes_per_word = mcspi_bytes_per_word(word_len); + dev_err(&spi->dev, "DMA RX penultimate word empty\n"); + count -= (bytes_per_word << 1); + omap2_mcspi_set_enable(spi, 1); + return count; + } + } + if (likely(mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHSTAT0) + & OMAP2_MCSPI_CHSTAT_RXS)) { + u32 w; + + w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0); + if (word_len <= 8) + ((u8 *)xfer->rx_buf)[elements] = w; + else if (word_len <= 16) + ((u16 *)xfer->rx_buf)[elements] = w; + else /* word_len <= 32 */ + ((u32 *)xfer->rx_buf)[elements] = w; + } else { + dev_err(&spi->dev, "DMA RX last word empty\n"); + count -= mcspi_bytes_per_word(word_len); + } + omap2_mcspi_set_enable(spi, 1); + return count; +} + +static unsigned +omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer) +{ + struct omap2_mcspi *mcspi; + struct omap2_mcspi_cs *cs = spi->controller_state; + struct omap2_mcspi_dma *mcspi_dma; + unsigned int count; + u32 l; + u8 *rx; + const u8 *tx; + struct dma_slave_config cfg; + enum dma_slave_buswidth width; + unsigned es; + u32 burst; + void __iomem *chstat_reg; + void __iomem *irqstat_reg; + int wait_res; + + mcspi = spi_master_get_devdata(spi->master); + mcspi_dma = &mcspi->dma_channels[spi->chip_select]; + l = mcspi_cached_chconf0(spi); + + + if (cs->word_len <= 8) { + width = DMA_SLAVE_BUSWIDTH_1_BYTE; + es = 1; + } else if (cs->word_len <= 16) { + width = DMA_SLAVE_BUSWIDTH_2_BYTES; + es = 2; + } else { + width = DMA_SLAVE_BUSWIDTH_4_BYTES; + es = 4; + } + + count = xfer->len; + burst = 1; + + if (mcspi->fifo_depth > 0) { + if (count > mcspi->fifo_depth) + burst = mcspi->fifo_depth / es; + else + burst = count / es; + } + + memset(&cfg, 0, sizeof(cfg)); + cfg.src_addr = cs->phys + OMAP2_MCSPI_RX0; + cfg.dst_addr = cs->phys + OMAP2_MCSPI_TX0; + cfg.src_addr_width = width; + cfg.dst_addr_width = width; + cfg.src_maxburst = burst; + cfg.dst_maxburst = burst; + + rx = xfer->rx_buf; + tx = xfer->tx_buf; + + if (tx != NULL) + omap2_mcspi_tx_dma(spi, xfer, cfg); + + if (rx != NULL) + count = omap2_mcspi_rx_dma(spi, xfer, cfg, es); + + if (tx != NULL) { + wait_for_completion(&mcspi_dma->dma_tx_completion); + dma_unmap_single(mcspi->dev, xfer->tx_dma, xfer->len, + DMA_TO_DEVICE); + + if (mcspi->fifo_depth > 0) { + irqstat_reg = mcspi->base + OMAP2_MCSPI_IRQSTATUS; + + if (mcspi_wait_for_reg_bit(irqstat_reg, + OMAP2_MCSPI_IRQSTATUS_EOW) < 0) + dev_err(&spi->dev, "EOW timed out\n"); + + mcspi_write_reg(mcspi->master, OMAP2_MCSPI_IRQSTATUS, + OMAP2_MCSPI_IRQSTATUS_EOW); + } + + /* for TX_ONLY mode, be sure all words have shifted out */ + if (rx == NULL) { + chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0; + if (mcspi->fifo_depth > 0) { + wait_res = mcspi_wait_for_reg_bit(chstat_reg, + OMAP2_MCSPI_CHSTAT_TXFFE); + if (wait_res < 0) + dev_err(&spi->dev, "TXFFE timed out\n"); + } else { + wait_res = mcspi_wait_for_reg_bit(chstat_reg, + OMAP2_MCSPI_CHSTAT_TXS); + if (wait_res < 0) + dev_err(&spi->dev, "TXS timed out\n"); + } + if (wait_res >= 0 && + (mcspi_wait_for_reg_bit(chstat_reg, + OMAP2_MCSPI_CHSTAT_EOT) < 0)) + dev_err(&spi->dev, "EOT timed out\n"); + } + } + return count; +} + +static unsigned +omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer) +{ + struct omap2_mcspi *mcspi; + struct omap2_mcspi_cs *cs = spi->controller_state; + unsigned int count, c; + u32 l; + void __iomem *base = cs->base; + void __iomem *tx_reg; + void __iomem *rx_reg; + void __iomem *chstat_reg; + int word_len; + + mcspi = spi_master_get_devdata(spi->master); + count = xfer->len; + c = count; + word_len = cs->word_len; + + l = mcspi_cached_chconf0(spi); + + /* We store the pre-calculated register addresses on stack to speed + * up the transfer loop. */ + tx_reg = base + OMAP2_MCSPI_TX0; + rx_reg = base + OMAP2_MCSPI_RX0; + chstat_reg = base + OMAP2_MCSPI_CHSTAT0; + + if (c < (word_len>>3)) + return 0; + + if (word_len <= 8) { + u8 *rx; + const u8 *tx; + + rx = xfer->rx_buf; + tx = xfer->tx_buf; + + do { + c -= 1; + if (tx != NULL) { + if (mcspi_wait_for_reg_bit(chstat_reg, + OMAP2_MCSPI_CHSTAT_TXS) < 0) { + dev_err(&spi->dev, "TXS timed out\n"); + goto out; + } + dev_vdbg(&spi->dev, "write-%d %02x\n", + word_len, *tx); + writel_relaxed(*tx++, tx_reg); + } + if (rx != NULL) { + if (mcspi_wait_for_reg_bit(chstat_reg, + OMAP2_MCSPI_CHSTAT_RXS) < 0) { + dev_err(&spi->dev, "RXS timed out\n"); + goto out; + } + + if (c == 1 && tx == NULL && + (l & OMAP2_MCSPI_CHCONF_TURBO)) { + omap2_mcspi_set_enable(spi, 0); + *rx++ = readl_relaxed(rx_reg); + dev_vdbg(&spi->dev, "read-%d %02x\n", + word_len, *(rx - 1)); + if (mcspi_wait_for_reg_bit(chstat_reg, + OMAP2_MCSPI_CHSTAT_RXS) < 0) { + dev_err(&spi->dev, + "RXS timed out\n"); + goto out; + } + c = 0; + } else if (c == 0 && tx == NULL) { + omap2_mcspi_set_enable(spi, 0); + } + + *rx++ = readl_relaxed(rx_reg); + dev_vdbg(&spi->dev, "read-%d %02x\n", + word_len, *(rx - 1)); + } + } while (c); + } else if (word_len <= 16) { + u16 *rx; + const u16 *tx; + + rx = xfer->rx_buf; + tx = xfer->tx_buf; + do { + c -= 2; + if (tx != NULL) { + if (mcspi_wait_for_reg_bit(chstat_reg, + OMAP2_MCSPI_CHSTAT_TXS) < 0) { + dev_err(&spi->dev, "TXS timed out\n"); + goto out; + } + dev_vdbg(&spi->dev, "write-%d %04x\n", + word_len, *tx); + writel_relaxed(*tx++, tx_reg); + } + if (rx != NULL) { + if (mcspi_wait_for_reg_bit(chstat_reg, + OMAP2_MCSPI_CHSTAT_RXS) < 0) { + dev_err(&spi->dev, "RXS timed out\n"); + goto out; + } + + if (c == 2 && tx == NULL && + (l & OMAP2_MCSPI_CHCONF_TURBO)) { + omap2_mcspi_set_enable(spi, 0); + *rx++ = readl_relaxed(rx_reg); + dev_vdbg(&spi->dev, "read-%d %04x\n", + word_len, *(rx - 1)); + if (mcspi_wait_for_reg_bit(chstat_reg, + OMAP2_MCSPI_CHSTAT_RXS) < 0) { + dev_err(&spi->dev, + "RXS timed out\n"); + goto out; + } + c = 0; + } else if (c == 0 && tx == NULL) { + omap2_mcspi_set_enable(spi, 0); + } + + *rx++ = readl_relaxed(rx_reg); + dev_vdbg(&spi->dev, "read-%d %04x\n", + word_len, *(rx - 1)); + } + } while (c >= 2); + } else if (word_len <= 32) { + u32 *rx; + const u32 *tx; + + rx = xfer->rx_buf; + tx = xfer->tx_buf; + do { + c -= 4; + if (tx != NULL) { + if (mcspi_wait_for_reg_bit(chstat_reg, + OMAP2_MCSPI_CHSTAT_TXS) < 0) { + dev_err(&spi->dev, "TXS timed out\n"); + goto out; + } + dev_vdbg(&spi->dev, "write-%d %08x\n", + word_len, *tx); + writel_relaxed(*tx++, tx_reg); + } + if (rx != NULL) { + if (mcspi_wait_for_reg_bit(chstat_reg, + OMAP2_MCSPI_CHSTAT_RXS) < 0) { + dev_err(&spi->dev, "RXS timed out\n"); + goto out; + } + + if (c == 4 && tx == NULL && + (l & OMAP2_MCSPI_CHCONF_TURBO)) { + omap2_mcspi_set_enable(spi, 0); + *rx++ = readl_relaxed(rx_reg); + dev_vdbg(&spi->dev, "read-%d %08x\n", + word_len, *(rx - 1)); + if (mcspi_wait_for_reg_bit(chstat_reg, + OMAP2_MCSPI_CHSTAT_RXS) < 0) { + dev_err(&spi->dev, + "RXS timed out\n"); + goto out; + } + c = 0; + } else if (c == 0 && tx == NULL) { + omap2_mcspi_set_enable(spi, 0); + } + + *rx++ = readl_relaxed(rx_reg); + dev_vdbg(&spi->dev, "read-%d %08x\n", + word_len, *(rx - 1)); + } + } while (c >= 4); + } + + /* for TX_ONLY mode, be sure all words have shifted out */ + if (xfer->rx_buf == NULL) { + if (mcspi_wait_for_reg_bit(chstat_reg, + OMAP2_MCSPI_CHSTAT_TXS) < 0) { + dev_err(&spi->dev, "TXS timed out\n"); + } else if (mcspi_wait_for_reg_bit(chstat_reg, + OMAP2_MCSPI_CHSTAT_EOT) < 0) + dev_err(&spi->dev, "EOT timed out\n"); + + /* disable chan to purge rx datas received in TX_ONLY transfer, + * otherwise these rx datas will affect the direct following + * RX_ONLY transfer. + */ + omap2_mcspi_set_enable(spi, 0); + } +out: + omap2_mcspi_set_enable(spi, 1); + return count - c; +} + +static u32 omap2_mcspi_calc_divisor(u32 speed_hz) +{ + u32 div; + + for (div = 0; div < 15; div++) + if (speed_hz >= (OMAP2_MCSPI_MAX_FREQ >> div)) + return div; + + return 15; +} + +/* called only when no transfer is active to this device */ +static int omap2_mcspi_setup_transfer(struct spi_device *spi, + struct spi_transfer *t) +{ + struct omap2_mcspi_cs *cs = spi->controller_state; + struct omap2_mcspi *mcspi; + struct spi_master *spi_cntrl; + u32 l = 0, clkd = 0, div, extclk = 0, clkg = 0; + u8 word_len = spi->bits_per_word; + u32 speed_hz = spi->max_speed_hz; + + mcspi = spi_master_get_devdata(spi->master); + spi_cntrl = mcspi->master; + + if (t != NULL && t->bits_per_word) + word_len = t->bits_per_word; + + cs->word_len = word_len; + + if (t && t->speed_hz) + speed_hz = t->speed_hz; + + speed_hz = min_t(u32, speed_hz, OMAP2_MCSPI_MAX_FREQ); + if (speed_hz < (OMAP2_MCSPI_MAX_FREQ / OMAP2_MCSPI_MAX_DIVIDER)) { + clkd = omap2_mcspi_calc_divisor(speed_hz); + speed_hz = OMAP2_MCSPI_MAX_FREQ >> clkd; + clkg = 0; + } else { + div = (OMAP2_MCSPI_MAX_FREQ + speed_hz - 1) / speed_hz; + speed_hz = OMAP2_MCSPI_MAX_FREQ / div; + clkd = (div - 1) & 0xf; + extclk = (div - 1) >> 4; + clkg = OMAP2_MCSPI_CHCONF_CLKG; + } + + l = mcspi_cached_chconf0(spi); + + /* standard 4-wire master mode: SCK, MOSI/out, MISO/in, nCS + * REVISIT: this controller could support SPI_3WIRE mode. + */ + if (mcspi->pin_dir == MCSPI_PINDIR_D0_IN_D1_OUT) { + l &= ~OMAP2_MCSPI_CHCONF_IS; + l &= ~OMAP2_MCSPI_CHCONF_DPE1; + l |= OMAP2_MCSPI_CHCONF_DPE0; + } else { + l |= OMAP2_MCSPI_CHCONF_IS; + l |= OMAP2_MCSPI_CHCONF_DPE1; + l &= ~OMAP2_MCSPI_CHCONF_DPE0; + } + + /* wordlength */ + l &= ~OMAP2_MCSPI_CHCONF_WL_MASK; + l |= (word_len - 1) << 7; + + /* set chipselect polarity; manage with FORCE */ + if (!(spi->mode & SPI_CS_HIGH)) + l |= OMAP2_MCSPI_CHCONF_EPOL; /* active-low; normal */ + else + l &= ~OMAP2_MCSPI_CHCONF_EPOL; + + /* set clock divisor */ + l &= ~OMAP2_MCSPI_CHCONF_CLKD_MASK; + l |= clkd << 2; + + /* set clock granularity */ + l &= ~OMAP2_MCSPI_CHCONF_CLKG; + l |= clkg; + if (clkg) { + cs->chctrl0 &= ~OMAP2_MCSPI_CHCTRL_EXTCLK_MASK; + cs->chctrl0 |= extclk << 8; + mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0); + } + + /* set SPI mode 0..3 */ + if (spi->mode & SPI_CPOL) + l |= OMAP2_MCSPI_CHCONF_POL; + else + l &= ~OMAP2_MCSPI_CHCONF_POL; + if (spi->mode & SPI_CPHA) + l |= OMAP2_MCSPI_CHCONF_PHA; + else + l &= ~OMAP2_MCSPI_CHCONF_PHA; + + mcspi_write_chconf0(spi, l); + + cs->mode = spi->mode; + + dev_dbg(&spi->dev, "setup: speed %d, sample %s edge, clk %s\n", + speed_hz, + (spi->mode & SPI_CPHA) ? "trailing" : "leading", + (spi->mode & SPI_CPOL) ? "inverted" : "normal"); + + return 0; +} + +/* + * Note that we currently allow DMA only if we get a channel + * for both rx and tx. Otherwise we'll do PIO for both rx and tx. + */ +static int omap2_mcspi_request_dma(struct spi_device *spi) +{ + struct spi_master *master = spi->master; + struct omap2_mcspi *mcspi; + struct omap2_mcspi_dma *mcspi_dma; + dma_cap_mask_t mask; + unsigned sig; + + mcspi = spi_master_get_devdata(master); + mcspi_dma = mcspi->dma_channels + spi->chip_select; + + init_completion(&mcspi_dma->dma_rx_completion); + init_completion(&mcspi_dma->dma_tx_completion); + + dma_cap_zero(mask); + dma_cap_set(DMA_SLAVE, mask); + sig = mcspi_dma->dma_rx_sync_dev; + + mcspi_dma->dma_rx = + dma_request_slave_channel_compat(mask, omap_dma_filter_fn, + &sig, &master->dev, + mcspi_dma->dma_rx_ch_name); + if (!mcspi_dma->dma_rx) + goto no_dma; + + sig = mcspi_dma->dma_tx_sync_dev; + mcspi_dma->dma_tx = + dma_request_slave_channel_compat(mask, omap_dma_filter_fn, + &sig, &master->dev, + mcspi_dma->dma_tx_ch_name); + + if (!mcspi_dma->dma_tx) { + dma_release_channel(mcspi_dma->dma_rx); + mcspi_dma->dma_rx = NULL; + goto no_dma; + } + + return 0; + +no_dma: + dev_warn(&spi->dev, "not using DMA for McSPI\n"); + return -EAGAIN; +} + +static int omap2_mcspi_setup(struct spi_device *spi) +{ + int ret; + struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master); + struct omap2_mcspi_regs *ctx = &mcspi->ctx; + struct omap2_mcspi_dma *mcspi_dma; + struct omap2_mcspi_cs *cs = spi->controller_state; + + mcspi_dma = &mcspi->dma_channels[spi->chip_select]; + + if (!cs) { + cs = kzalloc(sizeof *cs, GFP_KERNEL); + if (!cs) + return -ENOMEM; + cs->base = mcspi->base + spi->chip_select * 0x14; + cs->phys = mcspi->phys + spi->chip_select * 0x14; + cs->mode = 0; + cs->chconf0 = 0; + cs->chctrl0 = 0; + spi->controller_state = cs; + /* Link this to context save list */ + list_add_tail(&cs->node, &ctx->cs); + } + + if (!mcspi_dma->dma_rx || !mcspi_dma->dma_tx) { + ret = omap2_mcspi_request_dma(spi); + if (ret < 0 && ret != -EAGAIN) + return ret; + } + + ret = pm_runtime_get_sync(mcspi->dev); + if (ret < 0) + return ret; + + ret = omap2_mcspi_setup_transfer(spi, NULL); + pm_runtime_mark_last_busy(mcspi->dev); + pm_runtime_put_autosuspend(mcspi->dev); + + return ret; +} + +static void omap2_mcspi_cleanup(struct spi_device *spi) +{ + struct omap2_mcspi *mcspi; + struct omap2_mcspi_dma *mcspi_dma; + struct omap2_mcspi_cs *cs; + + mcspi = spi_master_get_devdata(spi->master); + + if (spi->controller_state) { + /* Unlink controller state from context save list */ + cs = spi->controller_state; + list_del(&cs->node); + + kfree(cs); + } + + if (spi->chip_select < spi->master->num_chipselect) { + mcspi_dma = &mcspi->dma_channels[spi->chip_select]; + + if (mcspi_dma->dma_rx) { + dma_release_channel(mcspi_dma->dma_rx); + mcspi_dma->dma_rx = NULL; + } + if (mcspi_dma->dma_tx) { + dma_release_channel(mcspi_dma->dma_tx); + mcspi_dma->dma_tx = NULL; + } + } +} + +static void omap2_mcspi_work(struct omap2_mcspi *mcspi, struct spi_message *m) +{ + + /* We only enable one channel at a time -- the one whose message is + * -- although this controller would gladly + * arbitrate among multiple channels. This corresponds to "single + * channel" master mode. As a side effect, we need to manage the + * chipselect with the FORCE bit ... CS != channel enable. + */ + + struct spi_device *spi; + struct spi_transfer *t = NULL; + struct spi_master *master; + struct omap2_mcspi_dma *mcspi_dma; + int cs_active = 0; + struct omap2_mcspi_cs *cs; + struct omap2_mcspi_device_config *cd; + int par_override = 0; + int status = 0; + u32 chconf; + + spi = m->spi; + master = spi->master; + mcspi_dma = mcspi->dma_channels + spi->chip_select; + cs = spi->controller_state; + cd = spi->controller_data; + + /* + * The slave driver could have changed spi->mode in which case + * it will be different from cs->mode (the current hardware setup). + * If so, set par_override (even though its not a parity issue) so + * omap2_mcspi_setup_transfer will be called to configure the hardware + * with the correct mode on the first iteration of the loop below. + */ + if (spi->mode != cs->mode) + par_override = 1; + + omap2_mcspi_set_enable(spi, 0); + list_for_each_entry(t, &m->transfers, transfer_list) { + if (t->tx_buf == NULL && t->rx_buf == NULL && t->len) { + status = -EINVAL; + break; + } + if (par_override || + (t->speed_hz != spi->max_speed_hz) || + (t->bits_per_word != spi->bits_per_word)) { + par_override = 1; + status = omap2_mcspi_setup_transfer(spi, t); + if (status < 0) + break; + if (t->speed_hz == spi->max_speed_hz && + t->bits_per_word == spi->bits_per_word) + par_override = 0; + } + if (cd && cd->cs_per_word) { + chconf = mcspi->ctx.modulctrl; + chconf &= ~OMAP2_MCSPI_MODULCTRL_SINGLE; + mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf); + mcspi->ctx.modulctrl = + mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL); + } + + + if (!cs_active) { + omap2_mcspi_force_cs(spi, 1); + cs_active = 1; + } + + chconf = mcspi_cached_chconf0(spi); + chconf &= ~OMAP2_MCSPI_CHCONF_TRM_MASK; + chconf &= ~OMAP2_MCSPI_CHCONF_TURBO; + + if (t->tx_buf == NULL) + chconf |= OMAP2_MCSPI_CHCONF_TRM_RX_ONLY; + else if (t->rx_buf == NULL) + chconf |= OMAP2_MCSPI_CHCONF_TRM_TX_ONLY; + + if (cd && cd->turbo_mode && t->tx_buf == NULL) { + /* Turbo mode is for more than one word */ + if (t->len > ((cs->word_len + 7) >> 3)) + chconf |= OMAP2_MCSPI_CHCONF_TURBO; + } + + mcspi_write_chconf0(spi, chconf); + + if (t->len) { + unsigned count; + + if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) && + (m->is_dma_mapped || t->len >= DMA_MIN_BYTES)) + omap2_mcspi_set_fifo(spi, t, 1); + + omap2_mcspi_set_enable(spi, 1); + + /* RX_ONLY mode needs dummy data in TX reg */ + if (t->tx_buf == NULL) + writel_relaxed(0, cs->base + + OMAP2_MCSPI_TX0); + + if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) && + (m->is_dma_mapped || t->len >= DMA_MIN_BYTES)) + count = omap2_mcspi_txrx_dma(spi, t); + else + count = omap2_mcspi_txrx_pio(spi, t); + m->actual_length += count; + + if (count != t->len) { + status = -EIO; + break; + } + } + + if (t->delay_usecs) + udelay(t->delay_usecs); + + /* ignore the "leave it on after last xfer" hint */ + if (t->cs_change) { + omap2_mcspi_force_cs(spi, 0); + cs_active = 0; + } + + omap2_mcspi_set_enable(spi, 0); + + if (mcspi->fifo_depth > 0) + omap2_mcspi_set_fifo(spi, t, 0); + } + /* Restore defaults if they were overriden */ + if (par_override) { + par_override = 0; + status = omap2_mcspi_setup_transfer(spi, NULL); + } + + if (cs_active) + omap2_mcspi_force_cs(spi, 0); + + if (cd && cd->cs_per_word) { + chconf = mcspi->ctx.modulctrl; + chconf |= OMAP2_MCSPI_MODULCTRL_SINGLE; + mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf); + mcspi->ctx.modulctrl = + mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL); + } + + omap2_mcspi_set_enable(spi, 0); + + if (mcspi->fifo_depth > 0 && t) + omap2_mcspi_set_fifo(spi, t, 0); + + m->status = status; +} + +static int omap2_mcspi_transfer_one_message(struct spi_master *master, + struct spi_message *m) +{ + struct spi_device *spi; + struct omap2_mcspi *mcspi; + struct omap2_mcspi_dma *mcspi_dma; + struct spi_transfer *t; + int status; + + spi = m->spi; + mcspi = spi_master_get_devdata(master); + mcspi_dma = mcspi->dma_channels + spi->chip_select; + m->actual_length = 0; + m->status = 0; + + list_for_each_entry(t, &m->transfers, transfer_list) { + const void *tx_buf = t->tx_buf; + void *rx_buf = t->rx_buf; + unsigned len = t->len; + + if ((len && !(rx_buf || tx_buf))) { + dev_dbg(mcspi->dev, "transfer: %d Hz, %d %s%s, %d bpw\n", + t->speed_hz, + len, + tx_buf ? "tx" : "", + rx_buf ? "rx" : "", + t->bits_per_word); + status = -EINVAL; + goto out; + } + + if (m->is_dma_mapped || len < DMA_MIN_BYTES) + continue; + + if (mcspi_dma->dma_tx && tx_buf != NULL) { + t->tx_dma = dma_map_single(mcspi->dev, (void *) tx_buf, + len, DMA_TO_DEVICE); + if (dma_mapping_error(mcspi->dev, t->tx_dma)) { + dev_dbg(mcspi->dev, "dma %cX %d bytes error\n", + 'T', len); + status = -EINVAL; + goto out; + } + } + if (mcspi_dma->dma_rx && rx_buf != NULL) { + t->rx_dma = dma_map_single(mcspi->dev, rx_buf, t->len, + DMA_FROM_DEVICE); + if (dma_mapping_error(mcspi->dev, t->rx_dma)) { + dev_dbg(mcspi->dev, "dma %cX %d bytes error\n", + 'R', len); + if (tx_buf != NULL) + dma_unmap_single(mcspi->dev, t->tx_dma, + len, DMA_TO_DEVICE); + status = -EINVAL; + goto out; + } + } + } + + omap2_mcspi_work(mcspi, m); + /* spi_finalize_current_message() changes the status inside the + * spi_message, save the status here. */ + status = m->status; +out: + spi_finalize_current_message(master); + return status; +} + +static int omap2_mcspi_master_setup(struct omap2_mcspi *mcspi) +{ + struct spi_master *master = mcspi->master; + struct omap2_mcspi_regs *ctx = &mcspi->ctx; + int ret = 0; + + ret = pm_runtime_get_sync(mcspi->dev); + if (ret < 0) + return ret; + + mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE, + OMAP2_MCSPI_WAKEUPENABLE_WKEN); + ctx->wakeupenable = OMAP2_MCSPI_WAKEUPENABLE_WKEN; + + omap2_mcspi_set_master_mode(master); + pm_runtime_mark_last_busy(mcspi->dev); + pm_runtime_put_autosuspend(mcspi->dev); + return 0; +} + +static int omap_mcspi_runtime_resume(struct device *dev) +{ + struct omap2_mcspi *mcspi; + struct spi_master *master; + + master = dev_get_drvdata(dev); + mcspi = spi_master_get_devdata(master); + omap2_mcspi_restore_ctx(mcspi); + + return 0; +} + +static struct omap2_mcspi_platform_config omap2_pdata = { + .regs_offset = 0, +}; + +static struct omap2_mcspi_platform_config omap4_pdata = { + .regs_offset = OMAP4_MCSPI_REG_OFFSET, +}; + +static const struct of_device_id omap_mcspi_of_match[] = { + { + .compatible = "ti,omap2-mcspi", + .data = &omap2_pdata, + }, + { + .compatible = "ti,omap4-mcspi", + .data = &omap4_pdata, + }, + { }, +}; +MODULE_DEVICE_TABLE(of, omap_mcspi_of_match); + +static int omap2_mcspi_probe(struct platform_device *pdev) +{ + struct spi_master *master; + const struct omap2_mcspi_platform_config *pdata; + struct omap2_mcspi *mcspi; + struct resource *r; + int status = 0, i; + u32 regs_offset = 0; + static int bus_num = 1; + struct device_node *node = pdev->dev.of_node; + const struct of_device_id *match; + + master = spi_alloc_master(&pdev->dev, sizeof *mcspi); + if (master == NULL) { + dev_dbg(&pdev->dev, "master allocation failed\n"); + return -ENOMEM; + } + + /* the spi->mode bits understood by this driver: */ + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH; + master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32); + master->setup = omap2_mcspi_setup; + master->auto_runtime_pm = true; + master->transfer_one_message = omap2_mcspi_transfer_one_message; + master->cleanup = omap2_mcspi_cleanup; + master->dev.of_node = node; + master->max_speed_hz = OMAP2_MCSPI_MAX_FREQ; + master->min_speed_hz = OMAP2_MCSPI_MAX_FREQ >> 15; + + platform_set_drvdata(pdev, master); + + mcspi = spi_master_get_devdata(master); + mcspi->master = master; + + match = of_match_device(omap_mcspi_of_match, &pdev->dev); + if (match) { + u32 num_cs = 1; /* default number of chipselect */ + pdata = match->data; + + of_property_read_u32(node, "ti,spi-num-cs", &num_cs); + master->num_chipselect = num_cs; + master->bus_num = bus_num++; + if (of_get_property(node, "ti,pindir-d0-out-d1-in", NULL)) + mcspi->pin_dir = MCSPI_PINDIR_D0_OUT_D1_IN; + } else { + pdata = dev_get_platdata(&pdev->dev); + master->num_chipselect = pdata->num_cs; + if (pdev->id != -1) + master->bus_num = pdev->id; + mcspi->pin_dir = pdata->pin_dir; + } + regs_offset = pdata->regs_offset; + + r = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (r == NULL) { + status = -ENODEV; + goto free_master; + } + + r->start += regs_offset; + r->end += regs_offset; + mcspi->phys = r->start; + + mcspi->base = devm_ioremap_resource(&pdev->dev, r); + if (IS_ERR(mcspi->base)) { + status = PTR_ERR(mcspi->base); + goto free_master; + } + + mcspi->dev = &pdev->dev; + + INIT_LIST_HEAD(&mcspi->ctx.cs); + + mcspi->dma_channels = devm_kcalloc(&pdev->dev, master->num_chipselect, + sizeof(struct omap2_mcspi_dma), + GFP_KERNEL); + if (mcspi->dma_channels == NULL) { + status = -ENOMEM; + goto free_master; + } + + for (i = 0; i < master->num_chipselect; i++) { + char *dma_rx_ch_name = mcspi->dma_channels[i].dma_rx_ch_name; + char *dma_tx_ch_name = mcspi->dma_channels[i].dma_tx_ch_name; + struct resource *dma_res; + + sprintf(dma_rx_ch_name, "rx%d", i); + if (!pdev->dev.of_node) { + dma_res = + platform_get_resource_byname(pdev, + IORESOURCE_DMA, + dma_rx_ch_name); + if (!dma_res) { + dev_dbg(&pdev->dev, + "cannot get DMA RX channel\n"); + status = -ENODEV; + break; + } + + mcspi->dma_channels[i].dma_rx_sync_dev = + dma_res->start; + } + sprintf(dma_tx_ch_name, "tx%d", i); + if (!pdev->dev.of_node) { + dma_res = + platform_get_resource_byname(pdev, + IORESOURCE_DMA, + dma_tx_ch_name); + if (!dma_res) { + dev_dbg(&pdev->dev, + "cannot get DMA TX channel\n"); + status = -ENODEV; + break; + } + + mcspi->dma_channels[i].dma_tx_sync_dev = + dma_res->start; + } + } + + if (status < 0) + goto free_master; + + pm_runtime_use_autosuspend(&pdev->dev); + pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT); + pm_runtime_enable(&pdev->dev); + + status = omap2_mcspi_master_setup(mcspi); + if (status < 0) + goto disable_pm; + + status = devm_spi_register_master(&pdev->dev, master); + if (status < 0) + goto disable_pm; + + return status; + +disable_pm: + pm_runtime_disable(&pdev->dev); +free_master: + spi_master_put(master); + return status; +} + +static int omap2_mcspi_remove(struct platform_device *pdev) +{ + struct spi_master *master = platform_get_drvdata(pdev); + struct omap2_mcspi *mcspi = spi_master_get_devdata(master); + + pm_runtime_put_sync(mcspi->dev); + pm_runtime_disable(&pdev->dev); + + return 0; +} + +/* work with hotplug and coldplug */ +MODULE_ALIAS("platform:omap2_mcspi"); + +#ifdef CONFIG_SUSPEND +/* + * When SPI wake up from off-mode, CS is in activate state. If it was in + * unactive state when driver was suspend, then force it to unactive state at + * wake up. + */ +static int omap2_mcspi_resume(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct omap2_mcspi *mcspi = spi_master_get_devdata(master); + struct omap2_mcspi_regs *ctx = &mcspi->ctx; + struct omap2_mcspi_cs *cs; + + pm_runtime_get_sync(mcspi->dev); + list_for_each_entry(cs, &ctx->cs, node) { + if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE) == 0) { + /* + * We need to toggle CS state for OMAP take this + * change in account. + */ + cs->chconf0 |= OMAP2_MCSPI_CHCONF_FORCE; + writel_relaxed(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0); + cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE; + writel_relaxed(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0); + } + } + pm_runtime_mark_last_busy(mcspi->dev); + pm_runtime_put_autosuspend(mcspi->dev); + return 0; +} +#else +#define omap2_mcspi_resume NULL +#endif + +static const struct dev_pm_ops omap2_mcspi_pm_ops = { + .resume = omap2_mcspi_resume, + .runtime_resume = omap_mcspi_runtime_resume, +}; + +static struct platform_driver omap2_mcspi_driver = { + .driver = { + .name = "omap2_mcspi", + .pm = &omap2_mcspi_pm_ops, + .of_match_table = omap_mcspi_of_match, + }, + .probe = omap2_mcspi_probe, + .remove = omap2_mcspi_remove, +}; + +module_platform_driver(omap2_mcspi_driver); +MODULE_LICENSE("GPL"); diff --git a/drivers/spi/spi-orion.c b/drivers/spi/spi-orion.c new file mode 100644 index 000000000..ff97cabda --- /dev/null +++ b/drivers/spi/spi-orion.c @@ -0,0 +1,572 @@ +/* + * Marvell Orion SPI controller driver + * + * Author: Shadi Ammouri <shadi@marvell.com> + * Copyright (C) 2007-2008 Marvell Ltd. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/interrupt.h> +#include <linux/delay.h> +#include <linux/platform_device.h> +#include <linux/err.h> +#include <linux/io.h> +#include <linux/spi/spi.h> +#include <linux/module.h> +#include <linux/pm_runtime.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/clk.h> +#include <linux/sizes.h> +#include <asm/unaligned.h> + +#define DRIVER_NAME "orion_spi" + +/* Runtime PM autosuspend timeout: PM is fairly light on this driver */ +#define SPI_AUTOSUSPEND_TIMEOUT 200 + +/* Some SoCs using this driver support up to 8 chip selects. + * It is up to the implementer to only use the chip selects + * that are available. + */ +#define ORION_NUM_CHIPSELECTS 8 + +#define ORION_SPI_WAIT_RDY_MAX_LOOP 2000 /* in usec */ + +#define ORION_SPI_IF_CTRL_REG 0x00 +#define ORION_SPI_IF_CONFIG_REG 0x04 +#define ORION_SPI_DATA_OUT_REG 0x08 +#define ORION_SPI_DATA_IN_REG 0x0c +#define ORION_SPI_INT_CAUSE_REG 0x10 + +#define ORION_SPI_MODE_CPOL (1 << 11) +#define ORION_SPI_MODE_CPHA (1 << 12) +#define ORION_SPI_IF_8_16_BIT_MODE (1 << 5) +#define ORION_SPI_CLK_PRESCALE_MASK 0x1F +#define ARMADA_SPI_CLK_PRESCALE_MASK 0xDF +#define ORION_SPI_MODE_MASK (ORION_SPI_MODE_CPOL | \ + ORION_SPI_MODE_CPHA) +#define ORION_SPI_CS_MASK 0x1C +#define ORION_SPI_CS_SHIFT 2 +#define ORION_SPI_CS(cs) ((cs << ORION_SPI_CS_SHIFT) & \ + ORION_SPI_CS_MASK) + +enum orion_spi_type { + ORION_SPI, + ARMADA_SPI, +}; + +struct orion_spi_dev { + enum orion_spi_type typ; + /* + * min_divisor and max_hz should be exclusive, the only we can + * have both is for managing the armada-370-spi case with old + * device tree + */ + unsigned long max_hz; + unsigned int min_divisor; + unsigned int max_divisor; + u32 prescale_mask; +}; + +struct orion_spi { + struct spi_master *master; + void __iomem *base; + struct clk *clk; + const struct orion_spi_dev *devdata; +}; + +static inline void __iomem *spi_reg(struct orion_spi *orion_spi, u32 reg) +{ + return orion_spi->base + reg; +} + +static inline void +orion_spi_setbits(struct orion_spi *orion_spi, u32 reg, u32 mask) +{ + void __iomem *reg_addr = spi_reg(orion_spi, reg); + u32 val; + + val = readl(reg_addr); + val |= mask; + writel(val, reg_addr); +} + +static inline void +orion_spi_clrbits(struct orion_spi *orion_spi, u32 reg, u32 mask) +{ + void __iomem *reg_addr = spi_reg(orion_spi, reg); + u32 val; + + val = readl(reg_addr); + val &= ~mask; + writel(val, reg_addr); +} + +static int orion_spi_baudrate_set(struct spi_device *spi, unsigned int speed) +{ + u32 tclk_hz; + u32 rate; + u32 prescale; + u32 reg; + struct orion_spi *orion_spi; + const struct orion_spi_dev *devdata; + + orion_spi = spi_master_get_devdata(spi->master); + devdata = orion_spi->devdata; + + tclk_hz = clk_get_rate(orion_spi->clk); + + if (devdata->typ == ARMADA_SPI) { + unsigned int clk, spr, sppr, sppr2, err; + unsigned int best_spr, best_sppr, best_err; + + best_err = speed; + best_spr = 0; + best_sppr = 0; + + /* Iterate over the valid range looking for best fit */ + for (sppr = 0; sppr < 8; sppr++) { + sppr2 = 0x1 << sppr; + + spr = tclk_hz / sppr2; + spr = DIV_ROUND_UP(spr, speed); + if ((spr == 0) || (spr > 15)) + continue; + + clk = tclk_hz / (spr * sppr2); + err = speed - clk; + + if (err < best_err) { + best_spr = spr; + best_sppr = sppr; + best_err = err; + } + } + + if ((best_sppr == 0) && (best_spr == 0)) + return -EINVAL; + + prescale = ((best_sppr & 0x6) << 5) | + ((best_sppr & 0x1) << 4) | best_spr; + } else { + /* + * the supported rates are: 4,6,8...30 + * round up as we look for equal or less speed + */ + rate = DIV_ROUND_UP(tclk_hz, speed); + rate = roundup(rate, 2); + + /* check if requested speed is too small */ + if (rate > 30) + return -EINVAL; + + if (rate < 4) + rate = 4; + + /* Convert the rate to SPI clock divisor value. */ + prescale = 0x10 + rate/2; + } + + reg = readl(spi_reg(orion_spi, ORION_SPI_IF_CONFIG_REG)); + reg = ((reg & ~devdata->prescale_mask) | prescale); + writel(reg, spi_reg(orion_spi, ORION_SPI_IF_CONFIG_REG)); + + return 0; +} + +static void +orion_spi_mode_set(struct spi_device *spi) +{ + u32 reg; + struct orion_spi *orion_spi; + + orion_spi = spi_master_get_devdata(spi->master); + + reg = readl(spi_reg(orion_spi, ORION_SPI_IF_CONFIG_REG)); + reg &= ~ORION_SPI_MODE_MASK; + if (spi->mode & SPI_CPOL) + reg |= ORION_SPI_MODE_CPOL; + if (spi->mode & SPI_CPHA) + reg |= ORION_SPI_MODE_CPHA; + writel(reg, spi_reg(orion_spi, ORION_SPI_IF_CONFIG_REG)); +} + +/* + * called only when no transfer is active on the bus + */ +static int +orion_spi_setup_transfer(struct spi_device *spi, struct spi_transfer *t) +{ + struct orion_spi *orion_spi; + unsigned int speed = spi->max_speed_hz; + unsigned int bits_per_word = spi->bits_per_word; + int rc; + + orion_spi = spi_master_get_devdata(spi->master); + + if ((t != NULL) && t->speed_hz) + speed = t->speed_hz; + + if ((t != NULL) && t->bits_per_word) + bits_per_word = t->bits_per_word; + + orion_spi_mode_set(spi); + + rc = orion_spi_baudrate_set(spi, speed); + if (rc) + return rc; + + if (bits_per_word == 16) + orion_spi_setbits(orion_spi, ORION_SPI_IF_CONFIG_REG, + ORION_SPI_IF_8_16_BIT_MODE); + else + orion_spi_clrbits(orion_spi, ORION_SPI_IF_CONFIG_REG, + ORION_SPI_IF_8_16_BIT_MODE); + + return 0; +} + +static void orion_spi_set_cs(struct spi_device *spi, bool enable) +{ + struct orion_spi *orion_spi; + + orion_spi = spi_master_get_devdata(spi->master); + + orion_spi_clrbits(orion_spi, ORION_SPI_IF_CTRL_REG, ORION_SPI_CS_MASK); + orion_spi_setbits(orion_spi, ORION_SPI_IF_CTRL_REG, + ORION_SPI_CS(spi->chip_select)); + + /* Chip select logic is inverted from spi_set_cs */ + if (!enable) + orion_spi_setbits(orion_spi, ORION_SPI_IF_CTRL_REG, 0x1); + else + orion_spi_clrbits(orion_spi, ORION_SPI_IF_CTRL_REG, 0x1); +} + +static inline int orion_spi_wait_till_ready(struct orion_spi *orion_spi) +{ + int i; + + for (i = 0; i < ORION_SPI_WAIT_RDY_MAX_LOOP; i++) { + if (readl(spi_reg(orion_spi, ORION_SPI_INT_CAUSE_REG))) + return 1; + + udelay(1); + } + + return -1; +} + +static inline int +orion_spi_write_read_8bit(struct spi_device *spi, + const u8 **tx_buf, u8 **rx_buf) +{ + void __iomem *tx_reg, *rx_reg, *int_reg; + struct orion_spi *orion_spi; + + orion_spi = spi_master_get_devdata(spi->master); + tx_reg = spi_reg(orion_spi, ORION_SPI_DATA_OUT_REG); + rx_reg = spi_reg(orion_spi, ORION_SPI_DATA_IN_REG); + int_reg = spi_reg(orion_spi, ORION_SPI_INT_CAUSE_REG); + + /* clear the interrupt cause register */ + writel(0x0, int_reg); + + if (tx_buf && *tx_buf) + writel(*(*tx_buf)++, tx_reg); + else + writel(0, tx_reg); + + if (orion_spi_wait_till_ready(orion_spi) < 0) { + dev_err(&spi->dev, "TXS timed out\n"); + return -1; + } + + if (rx_buf && *rx_buf) + *(*rx_buf)++ = readl(rx_reg); + + return 1; +} + +static inline int +orion_spi_write_read_16bit(struct spi_device *spi, + const u16 **tx_buf, u16 **rx_buf) +{ + void __iomem *tx_reg, *rx_reg, *int_reg; + struct orion_spi *orion_spi; + + orion_spi = spi_master_get_devdata(spi->master); + tx_reg = spi_reg(orion_spi, ORION_SPI_DATA_OUT_REG); + rx_reg = spi_reg(orion_spi, ORION_SPI_DATA_IN_REG); + int_reg = spi_reg(orion_spi, ORION_SPI_INT_CAUSE_REG); + + /* clear the interrupt cause register */ + writel(0x0, int_reg); + + if (tx_buf && *tx_buf) + writel(__cpu_to_le16(get_unaligned((*tx_buf)++)), tx_reg); + else + writel(0, tx_reg); + + if (orion_spi_wait_till_ready(orion_spi) < 0) { + dev_err(&spi->dev, "TXS timed out\n"); + return -1; + } + + if (rx_buf && *rx_buf) + put_unaligned(__le16_to_cpu(readl(rx_reg)), (*rx_buf)++); + + return 1; +} + +static unsigned int +orion_spi_write_read(struct spi_device *spi, struct spi_transfer *xfer) +{ + unsigned int count; + int word_len; + + word_len = spi->bits_per_word; + count = xfer->len; + + if (word_len == 8) { + const u8 *tx = xfer->tx_buf; + u8 *rx = xfer->rx_buf; + + do { + if (orion_spi_write_read_8bit(spi, &tx, &rx) < 0) + goto out; + count--; + } while (count); + } else if (word_len == 16) { + const u16 *tx = xfer->tx_buf; + u16 *rx = xfer->rx_buf; + + do { + if (orion_spi_write_read_16bit(spi, &tx, &rx) < 0) + goto out; + count -= 2; + } while (count); + } + +out: + return xfer->len - count; +} + +static int orion_spi_transfer_one(struct spi_master *master, + struct spi_device *spi, + struct spi_transfer *t) +{ + int status = 0; + + status = orion_spi_setup_transfer(spi, t); + if (status < 0) + return status; + + if (t->len) + orion_spi_write_read(spi, t); + + return status; +} + +static int orion_spi_setup(struct spi_device *spi) +{ + return orion_spi_setup_transfer(spi, NULL); +} + +static int orion_spi_reset(struct orion_spi *orion_spi) +{ + /* Verify that the CS is deasserted */ + orion_spi_clrbits(orion_spi, ORION_SPI_IF_CTRL_REG, 0x1); + return 0; +} + +static const struct orion_spi_dev orion_spi_dev_data = { + .typ = ORION_SPI, + .min_divisor = 4, + .max_divisor = 30, + .prescale_mask = ORION_SPI_CLK_PRESCALE_MASK, +}; + +static const struct orion_spi_dev armada_spi_dev_data = { + .typ = ARMADA_SPI, + .min_divisor = 4, + .max_divisor = 1920, + .max_hz = 50000000, + .prescale_mask = ARMADA_SPI_CLK_PRESCALE_MASK, +}; + +static const struct of_device_id orion_spi_of_match_table[] = { + { .compatible = "marvell,orion-spi", .data = &orion_spi_dev_data, }, + { .compatible = "marvell,armada-370-spi", .data = &armada_spi_dev_data, }, + {} +}; +MODULE_DEVICE_TABLE(of, orion_spi_of_match_table); + +static int orion_spi_probe(struct platform_device *pdev) +{ + const struct of_device_id *of_id; + const struct orion_spi_dev *devdata; + struct spi_master *master; + struct orion_spi *spi; + struct resource *r; + unsigned long tclk_hz; + int status = 0; + + master = spi_alloc_master(&pdev->dev, sizeof(*spi)); + if (master == NULL) { + dev_dbg(&pdev->dev, "master allocation failed\n"); + return -ENOMEM; + } + + if (pdev->id != -1) + master->bus_num = pdev->id; + if (pdev->dev.of_node) { + u32 cell_index; + + if (!of_property_read_u32(pdev->dev.of_node, "cell-index", + &cell_index)) + master->bus_num = cell_index; + } + + /* we support only mode 0, and no options */ + master->mode_bits = SPI_CPHA | SPI_CPOL; + master->set_cs = orion_spi_set_cs; + master->transfer_one = orion_spi_transfer_one; + master->num_chipselect = ORION_NUM_CHIPSELECTS; + master->setup = orion_spi_setup; + master->bits_per_word_mask = SPI_BPW_MASK(8) | SPI_BPW_MASK(16); + master->auto_runtime_pm = true; + + platform_set_drvdata(pdev, master); + + spi = spi_master_get_devdata(master); + spi->master = master; + + of_id = of_match_device(orion_spi_of_match_table, &pdev->dev); + devdata = (of_id) ? of_id->data : &orion_spi_dev_data; + spi->devdata = devdata; + + spi->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(spi->clk)) { + status = PTR_ERR(spi->clk); + goto out; + } + + status = clk_prepare_enable(spi->clk); + if (status) + goto out; + + tclk_hz = clk_get_rate(spi->clk); + + /* + * With old device tree, armada-370-spi could be used with + * Armada XP, however for this SoC the maximum frequency is + * 50MHz instead of tclk/4. On Armada 370, tclk cannot be + * higher than 200MHz. So, in order to be able to handle both + * SoCs, we can take the minimum of 50MHz and tclk/4. + */ + if (of_device_is_compatible(pdev->dev.of_node, + "marvell,armada-370-spi")) + master->max_speed_hz = min(devdata->max_hz, + DIV_ROUND_UP(tclk_hz, devdata->min_divisor)); + else + master->max_speed_hz = + DIV_ROUND_UP(tclk_hz, devdata->min_divisor); + master->min_speed_hz = DIV_ROUND_UP(tclk_hz, devdata->max_divisor); + + r = platform_get_resource(pdev, IORESOURCE_MEM, 0); + spi->base = devm_ioremap_resource(&pdev->dev, r); + if (IS_ERR(spi->base)) { + status = PTR_ERR(spi->base); + goto out_rel_clk; + } + + pm_runtime_set_active(&pdev->dev); + pm_runtime_use_autosuspend(&pdev->dev); + pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT); + pm_runtime_enable(&pdev->dev); + + status = orion_spi_reset(spi); + if (status < 0) + goto out_rel_pm; + + pm_runtime_mark_last_busy(&pdev->dev); + pm_runtime_put_autosuspend(&pdev->dev); + + master->dev.of_node = pdev->dev.of_node; + status = spi_register_master(master); + if (status < 0) + goto out_rel_pm; + + return status; + +out_rel_pm: + pm_runtime_disable(&pdev->dev); +out_rel_clk: + clk_disable_unprepare(spi->clk); +out: + spi_master_put(master); + return status; +} + + +static int orion_spi_remove(struct platform_device *pdev) +{ + struct spi_master *master = platform_get_drvdata(pdev); + struct orion_spi *spi = spi_master_get_devdata(master); + + pm_runtime_get_sync(&pdev->dev); + clk_disable_unprepare(spi->clk); + + spi_unregister_master(master); + pm_runtime_disable(&pdev->dev); + + return 0; +} + +MODULE_ALIAS("platform:" DRIVER_NAME); + +#ifdef CONFIG_PM +static int orion_spi_runtime_suspend(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct orion_spi *spi = spi_master_get_devdata(master); + + clk_disable_unprepare(spi->clk); + return 0; +} + +static int orion_spi_runtime_resume(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct orion_spi *spi = spi_master_get_devdata(master); + + return clk_prepare_enable(spi->clk); +} +#endif + +static const struct dev_pm_ops orion_spi_pm_ops = { + SET_RUNTIME_PM_OPS(orion_spi_runtime_suspend, + orion_spi_runtime_resume, + NULL) +}; + +static struct platform_driver orion_spi_driver = { + .driver = { + .name = DRIVER_NAME, + .pm = &orion_spi_pm_ops, + .of_match_table = of_match_ptr(orion_spi_of_match_table), + }, + .probe = orion_spi_probe, + .remove = orion_spi_remove, +}; + +module_platform_driver(orion_spi_driver); + +MODULE_DESCRIPTION("Orion SPI driver"); +MODULE_AUTHOR("Shadi Ammouri <shadi@marvell.com>"); +MODULE_LICENSE("GPL"); diff --git a/drivers/spi/spi-pl022.c b/drivers/spi/spi-pl022.c new file mode 100644 index 000000000..94af80676 --- /dev/null +++ b/drivers/spi/spi-pl022.c @@ -0,0 +1,2492 @@ +/* + * A driver for the ARM PL022 PrimeCell SSP/SPI bus master. + * + * Copyright (C) 2008-2012 ST-Ericsson AB + * Copyright (C) 2006 STMicroelectronics Pvt. Ltd. + * + * Author: Linus Walleij <linus.walleij@stericsson.com> + * + * Initial version inspired by: + * linux-2.6.17-rc3-mm1/drivers/spi/pxa2xx_spi.c + * Initial adoption to PL022 by: + * Sachin Verma <sachin.verma@st.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/init.h> +#include <linux/module.h> +#include <linux/device.h> +#include <linux/ioport.h> +#include <linux/errno.h> +#include <linux/interrupt.h> +#include <linux/spi/spi.h> +#include <linux/delay.h> +#include <linux/clk.h> +#include <linux/err.h> +#include <linux/amba/bus.h> +#include <linux/amba/pl022.h> +#include <linux/io.h> +#include <linux/slab.h> +#include <linux/dmaengine.h> +#include <linux/dma-mapping.h> +#include <linux/scatterlist.h> +#include <linux/pm_runtime.h> +#include <linux/gpio.h> +#include <linux/of_gpio.h> +#include <linux/pinctrl/consumer.h> + +/* + * This macro is used to define some register default values. + * reg is masked with mask, the OR:ed with an (again masked) + * val shifted sb steps to the left. + */ +#define SSP_WRITE_BITS(reg, val, mask, sb) \ + ((reg) = (((reg) & ~(mask)) | (((val)<<(sb)) & (mask)))) + +/* + * This macro is also used to define some default values. + * It will just shift val by sb steps to the left and mask + * the result with mask. + */ +#define GEN_MASK_BITS(val, mask, sb) \ + (((val)<<(sb)) & (mask)) + +#define DRIVE_TX 0 +#define DO_NOT_DRIVE_TX 1 + +#define DO_NOT_QUEUE_DMA 0 +#define QUEUE_DMA 1 + +#define RX_TRANSFER 1 +#define TX_TRANSFER 2 + +/* + * Macros to access SSP Registers with their offsets + */ +#define SSP_CR0(r) (r + 0x000) +#define SSP_CR1(r) (r + 0x004) +#define SSP_DR(r) (r + 0x008) +#define SSP_SR(r) (r + 0x00C) +#define SSP_CPSR(r) (r + 0x010) +#define SSP_IMSC(r) (r + 0x014) +#define SSP_RIS(r) (r + 0x018) +#define SSP_MIS(r) (r + 0x01C) +#define SSP_ICR(r) (r + 0x020) +#define SSP_DMACR(r) (r + 0x024) +#define SSP_CSR(r) (r + 0x030) /* vendor extension */ +#define SSP_ITCR(r) (r + 0x080) +#define SSP_ITIP(r) (r + 0x084) +#define SSP_ITOP(r) (r + 0x088) +#define SSP_TDR(r) (r + 0x08C) + +#define SSP_PID0(r) (r + 0xFE0) +#define SSP_PID1(r) (r + 0xFE4) +#define SSP_PID2(r) (r + 0xFE8) +#define SSP_PID3(r) (r + 0xFEC) + +#define SSP_CID0(r) (r + 0xFF0) +#define SSP_CID1(r) (r + 0xFF4) +#define SSP_CID2(r) (r + 0xFF8) +#define SSP_CID3(r) (r + 0xFFC) + +/* + * SSP Control Register 0 - SSP_CR0 + */ +#define SSP_CR0_MASK_DSS (0x0FUL << 0) +#define SSP_CR0_MASK_FRF (0x3UL << 4) +#define SSP_CR0_MASK_SPO (0x1UL << 6) +#define SSP_CR0_MASK_SPH (0x1UL << 7) +#define SSP_CR0_MASK_SCR (0xFFUL << 8) + +/* + * The ST version of this block moves som bits + * in SSP_CR0 and extends it to 32 bits + */ +#define SSP_CR0_MASK_DSS_ST (0x1FUL << 0) +#define SSP_CR0_MASK_HALFDUP_ST (0x1UL << 5) +#define SSP_CR0_MASK_CSS_ST (0x1FUL << 16) +#define SSP_CR0_MASK_FRF_ST (0x3UL << 21) + +/* + * SSP Control Register 0 - SSP_CR1 + */ +#define SSP_CR1_MASK_LBM (0x1UL << 0) +#define SSP_CR1_MASK_SSE (0x1UL << 1) +#define SSP_CR1_MASK_MS (0x1UL << 2) +#define SSP_CR1_MASK_SOD (0x1UL << 3) + +/* + * The ST version of this block adds some bits + * in SSP_CR1 + */ +#define SSP_CR1_MASK_RENDN_ST (0x1UL << 4) +#define SSP_CR1_MASK_TENDN_ST (0x1UL << 5) +#define SSP_CR1_MASK_MWAIT_ST (0x1UL << 6) +#define SSP_CR1_MASK_RXIFLSEL_ST (0x7UL << 7) +#define SSP_CR1_MASK_TXIFLSEL_ST (0x7UL << 10) +/* This one is only in the PL023 variant */ +#define SSP_CR1_MASK_FBCLKDEL_ST (0x7UL << 13) + +/* + * SSP Status Register - SSP_SR + */ +#define SSP_SR_MASK_TFE (0x1UL << 0) /* Transmit FIFO empty */ +#define SSP_SR_MASK_TNF (0x1UL << 1) /* Transmit FIFO not full */ +#define SSP_SR_MASK_RNE (0x1UL << 2) /* Receive FIFO not empty */ +#define SSP_SR_MASK_RFF (0x1UL << 3) /* Receive FIFO full */ +#define SSP_SR_MASK_BSY (0x1UL << 4) /* Busy Flag */ + +/* + * SSP Clock Prescale Register - SSP_CPSR + */ +#define SSP_CPSR_MASK_CPSDVSR (0xFFUL << 0) + +/* + * SSP Interrupt Mask Set/Clear Register - SSP_IMSC + */ +#define SSP_IMSC_MASK_RORIM (0x1UL << 0) /* Receive Overrun Interrupt mask */ +#define SSP_IMSC_MASK_RTIM (0x1UL << 1) /* Receive timeout Interrupt mask */ +#define SSP_IMSC_MASK_RXIM (0x1UL << 2) /* Receive FIFO Interrupt mask */ +#define SSP_IMSC_MASK_TXIM (0x1UL << 3) /* Transmit FIFO Interrupt mask */ + +/* + * SSP Raw Interrupt Status Register - SSP_RIS + */ +/* Receive Overrun Raw Interrupt status */ +#define SSP_RIS_MASK_RORRIS (0x1UL << 0) +/* Receive Timeout Raw Interrupt status */ +#define SSP_RIS_MASK_RTRIS (0x1UL << 1) +/* Receive FIFO Raw Interrupt status */ +#define SSP_RIS_MASK_RXRIS (0x1UL << 2) +/* Transmit FIFO Raw Interrupt status */ +#define SSP_RIS_MASK_TXRIS (0x1UL << 3) + +/* + * SSP Masked Interrupt Status Register - SSP_MIS + */ +/* Receive Overrun Masked Interrupt status */ +#define SSP_MIS_MASK_RORMIS (0x1UL << 0) +/* Receive Timeout Masked Interrupt status */ +#define SSP_MIS_MASK_RTMIS (0x1UL << 1) +/* Receive FIFO Masked Interrupt status */ +#define SSP_MIS_MASK_RXMIS (0x1UL << 2) +/* Transmit FIFO Masked Interrupt status */ +#define SSP_MIS_MASK_TXMIS (0x1UL << 3) + +/* + * SSP Interrupt Clear Register - SSP_ICR + */ +/* Receive Overrun Raw Clear Interrupt bit */ +#define SSP_ICR_MASK_RORIC (0x1UL << 0) +/* Receive Timeout Clear Interrupt bit */ +#define SSP_ICR_MASK_RTIC (0x1UL << 1) + +/* + * SSP DMA Control Register - SSP_DMACR + */ +/* Receive DMA Enable bit */ +#define SSP_DMACR_MASK_RXDMAE (0x1UL << 0) +/* Transmit DMA Enable bit */ +#define SSP_DMACR_MASK_TXDMAE (0x1UL << 1) + +/* + * SSP Chip Select Control Register - SSP_CSR + * (vendor extension) + */ +#define SSP_CSR_CSVALUE_MASK (0x1FUL << 0) + +/* + * SSP Integration Test control Register - SSP_ITCR + */ +#define SSP_ITCR_MASK_ITEN (0x1UL << 0) +#define SSP_ITCR_MASK_TESTFIFO (0x1UL << 1) + +/* + * SSP Integration Test Input Register - SSP_ITIP + */ +#define ITIP_MASK_SSPRXD (0x1UL << 0) +#define ITIP_MASK_SSPFSSIN (0x1UL << 1) +#define ITIP_MASK_SSPCLKIN (0x1UL << 2) +#define ITIP_MASK_RXDMAC (0x1UL << 3) +#define ITIP_MASK_TXDMAC (0x1UL << 4) +#define ITIP_MASK_SSPTXDIN (0x1UL << 5) + +/* + * SSP Integration Test output Register - SSP_ITOP + */ +#define ITOP_MASK_SSPTXD (0x1UL << 0) +#define ITOP_MASK_SSPFSSOUT (0x1UL << 1) +#define ITOP_MASK_SSPCLKOUT (0x1UL << 2) +#define ITOP_MASK_SSPOEn (0x1UL << 3) +#define ITOP_MASK_SSPCTLOEn (0x1UL << 4) +#define ITOP_MASK_RORINTR (0x1UL << 5) +#define ITOP_MASK_RTINTR (0x1UL << 6) +#define ITOP_MASK_RXINTR (0x1UL << 7) +#define ITOP_MASK_TXINTR (0x1UL << 8) +#define ITOP_MASK_INTR (0x1UL << 9) +#define ITOP_MASK_RXDMABREQ (0x1UL << 10) +#define ITOP_MASK_RXDMASREQ (0x1UL << 11) +#define ITOP_MASK_TXDMABREQ (0x1UL << 12) +#define ITOP_MASK_TXDMASREQ (0x1UL << 13) + +/* + * SSP Test Data Register - SSP_TDR + */ +#define TDR_MASK_TESTDATA (0xFFFFFFFF) + +/* + * Message State + * we use the spi_message.state (void *) pointer to + * hold a single state value, that's why all this + * (void *) casting is done here. + */ +#define STATE_START ((void *) 0) +#define STATE_RUNNING ((void *) 1) +#define STATE_DONE ((void *) 2) +#define STATE_ERROR ((void *) -1) + +/* + * SSP State - Whether Enabled or Disabled + */ +#define SSP_DISABLED (0) +#define SSP_ENABLED (1) + +/* + * SSP DMA State - Whether DMA Enabled or Disabled + */ +#define SSP_DMA_DISABLED (0) +#define SSP_DMA_ENABLED (1) + +/* + * SSP Clock Defaults + */ +#define SSP_DEFAULT_CLKRATE 0x2 +#define SSP_DEFAULT_PRESCALE 0x40 + +/* + * SSP Clock Parameter ranges + */ +#define CPSDVR_MIN 0x02 +#define CPSDVR_MAX 0xFE +#define SCR_MIN 0x00 +#define SCR_MAX 0xFF + +/* + * SSP Interrupt related Macros + */ +#define DEFAULT_SSP_REG_IMSC 0x0UL +#define DISABLE_ALL_INTERRUPTS DEFAULT_SSP_REG_IMSC +#define ENABLE_ALL_INTERRUPTS ( \ + SSP_IMSC_MASK_RORIM | \ + SSP_IMSC_MASK_RTIM | \ + SSP_IMSC_MASK_RXIM | \ + SSP_IMSC_MASK_TXIM \ +) + +#define CLEAR_ALL_INTERRUPTS 0x3 + +#define SPI_POLLING_TIMEOUT 1000 + +/* + * The type of reading going on on this chip + */ +enum ssp_reading { + READING_NULL, + READING_U8, + READING_U16, + READING_U32 +}; + +/** + * The type of writing going on on this chip + */ +enum ssp_writing { + WRITING_NULL, + WRITING_U8, + WRITING_U16, + WRITING_U32 +}; + +/** + * struct vendor_data - vendor-specific config parameters + * for PL022 derivates + * @fifodepth: depth of FIFOs (both) + * @max_bpw: maximum number of bits per word + * @unidir: supports unidirection transfers + * @extended_cr: 32 bit wide control register 0 with extra + * features and extra features in CR1 as found in the ST variants + * @pl023: supports a subset of the ST extensions called "PL023" + * @internal_cs_ctrl: supports chip select control register + */ +struct vendor_data { + int fifodepth; + int max_bpw; + bool unidir; + bool extended_cr; + bool pl023; + bool loopback; + bool internal_cs_ctrl; +}; + +/** + * struct pl022 - This is the private SSP driver data structure + * @adev: AMBA device model hookup + * @vendor: vendor data for the IP block + * @phybase: the physical memory where the SSP device resides + * @virtbase: the virtual memory where the SSP is mapped + * @clk: outgoing clock "SPICLK" for the SPI bus + * @master: SPI framework hookup + * @master_info: controller-specific data from machine setup + * @kworker: thread struct for message pump + * @kworker_task: pointer to task for message pump kworker thread + * @pump_messages: work struct for scheduling work to the message pump + * @queue_lock: spinlock to syncronise access to message queue + * @queue: message queue + * @busy: message pump is busy + * @running: message pump is running + * @pump_transfers: Tasklet used in Interrupt Transfer mode + * @cur_msg: Pointer to current spi_message being processed + * @cur_transfer: Pointer to current spi_transfer + * @cur_chip: pointer to current clients chip(assigned from controller_state) + * @next_msg_cs_active: the next message in the queue has been examined + * and it was found that it uses the same chip select as the previous + * message, so we left it active after the previous transfer, and it's + * active already. + * @tx: current position in TX buffer to be read + * @tx_end: end position in TX buffer to be read + * @rx: current position in RX buffer to be written + * @rx_end: end position in RX buffer to be written + * @read: the type of read currently going on + * @write: the type of write currently going on + * @exp_fifo_level: expected FIFO level + * @dma_rx_channel: optional channel for RX DMA + * @dma_tx_channel: optional channel for TX DMA + * @sgt_rx: scattertable for the RX transfer + * @sgt_tx: scattertable for the TX transfer + * @dummypage: a dummy page used for driving data on the bus with DMA + * @cur_cs: current chip select (gpio) + * @chipselects: list of chipselects (gpios) + */ +struct pl022 { + struct amba_device *adev; + struct vendor_data *vendor; + resource_size_t phybase; + void __iomem *virtbase; + struct clk *clk; + struct spi_master *master; + struct pl022_ssp_controller *master_info; + /* Message per-transfer pump */ + struct tasklet_struct pump_transfers; + struct spi_message *cur_msg; + struct spi_transfer *cur_transfer; + struct chip_data *cur_chip; + bool next_msg_cs_active; + void *tx; + void *tx_end; + void *rx; + void *rx_end; + enum ssp_reading read; + enum ssp_writing write; + u32 exp_fifo_level; + enum ssp_rx_level_trig rx_lev_trig; + enum ssp_tx_level_trig tx_lev_trig; + /* DMA settings */ +#ifdef CONFIG_DMA_ENGINE + struct dma_chan *dma_rx_channel; + struct dma_chan *dma_tx_channel; + struct sg_table sgt_rx; + struct sg_table sgt_tx; + char *dummypage; + bool dma_running; +#endif + int cur_cs; + int *chipselects; +}; + +/** + * struct chip_data - To maintain runtime state of SSP for each client chip + * @cr0: Value of control register CR0 of SSP - on later ST variants this + * register is 32 bits wide rather than just 16 + * @cr1: Value of control register CR1 of SSP + * @dmacr: Value of DMA control Register of SSP + * @cpsr: Value of Clock prescale register + * @n_bytes: how many bytes(power of 2) reqd for a given data width of client + * @enable_dma: Whether to enable DMA or not + * @read: function ptr to be used to read when doing xfer for this chip + * @write: function ptr to be used to write when doing xfer for this chip + * @cs_control: chip select callback provided by chip + * @xfer_type: polling/interrupt/DMA + * + * Runtime state of the SSP controller, maintained per chip, + * This would be set according to the current message that would be served + */ +struct chip_data { + u32 cr0; + u16 cr1; + u16 dmacr; + u16 cpsr; + u8 n_bytes; + bool enable_dma; + enum ssp_reading read; + enum ssp_writing write; + void (*cs_control) (u32 command); + int xfer_type; +}; + +/** + * null_cs_control - Dummy chip select function + * @command: select/delect the chip + * + * If no chip select function is provided by client this is used as dummy + * chip select + */ +static void null_cs_control(u32 command) +{ + pr_debug("pl022: dummy chip select control, CS=0x%x\n", command); +} + +/** + * internal_cs_control - Control chip select signals via SSP_CSR. + * @pl022: SSP driver private data structure + * @command: select/delect the chip + * + * Used on controller with internal chip select control via SSP_CSR register + * (vendor extension). Each of the 5 LSB in the register controls one chip + * select signal. + */ +static void internal_cs_control(struct pl022 *pl022, u32 command) +{ + u32 tmp; + + tmp = readw(SSP_CSR(pl022->virtbase)); + if (command == SSP_CHIP_SELECT) + tmp &= ~BIT(pl022->cur_cs); + else + tmp |= BIT(pl022->cur_cs); + writew(tmp, SSP_CSR(pl022->virtbase)); +} + +static void pl022_cs_control(struct pl022 *pl022, u32 command) +{ + if (pl022->vendor->internal_cs_ctrl) + internal_cs_control(pl022, command); + else if (gpio_is_valid(pl022->cur_cs)) + gpio_set_value(pl022->cur_cs, command); + else + pl022->cur_chip->cs_control(command); +} + +/** + * giveback - current spi_message is over, schedule next message and call + * callback of this message. Assumes that caller already + * set message->status; dma and pio irqs are blocked + * @pl022: SSP driver private data structure + */ +static void giveback(struct pl022 *pl022) +{ + struct spi_transfer *last_transfer; + pl022->next_msg_cs_active = false; + + last_transfer = list_last_entry(&pl022->cur_msg->transfers, + struct spi_transfer, transfer_list); + + /* Delay if requested before any change in chip select */ + if (last_transfer->delay_usecs) + /* + * FIXME: This runs in interrupt context. + * Is this really smart? + */ + udelay(last_transfer->delay_usecs); + + if (!last_transfer->cs_change) { + struct spi_message *next_msg; + + /* + * cs_change was not set. We can keep the chip select + * enabled if there is message in the queue and it is + * for the same spi device. + * + * We cannot postpone this until pump_messages, because + * after calling msg->complete (below) the driver that + * sent the current message could be unloaded, which + * could invalidate the cs_control() callback... + */ + /* get a pointer to the next message, if any */ + next_msg = spi_get_next_queued_message(pl022->master); + + /* + * see if the next and current messages point + * to the same spi device. + */ + if (next_msg && next_msg->spi != pl022->cur_msg->spi) + next_msg = NULL; + if (!next_msg || pl022->cur_msg->state == STATE_ERROR) + pl022_cs_control(pl022, SSP_CHIP_DESELECT); + else + pl022->next_msg_cs_active = true; + + } + + pl022->cur_msg = NULL; + pl022->cur_transfer = NULL; + pl022->cur_chip = NULL; + + /* disable the SPI/SSP operation */ + writew((readw(SSP_CR1(pl022->virtbase)) & + (~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase)); + + spi_finalize_current_message(pl022->master); +} + +/** + * flush - flush the FIFO to reach a clean state + * @pl022: SSP driver private data structure + */ +static int flush(struct pl022 *pl022) +{ + unsigned long limit = loops_per_jiffy << 1; + + dev_dbg(&pl022->adev->dev, "flush\n"); + do { + while (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE) + readw(SSP_DR(pl022->virtbase)); + } while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_BSY) && limit--); + + pl022->exp_fifo_level = 0; + + return limit; +} + +/** + * restore_state - Load configuration of current chip + * @pl022: SSP driver private data structure + */ +static void restore_state(struct pl022 *pl022) +{ + struct chip_data *chip = pl022->cur_chip; + + if (pl022->vendor->extended_cr) + writel(chip->cr0, SSP_CR0(pl022->virtbase)); + else + writew(chip->cr0, SSP_CR0(pl022->virtbase)); + writew(chip->cr1, SSP_CR1(pl022->virtbase)); + writew(chip->dmacr, SSP_DMACR(pl022->virtbase)); + writew(chip->cpsr, SSP_CPSR(pl022->virtbase)); + writew(DISABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase)); + writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase)); +} + +/* + * Default SSP Register Values + */ +#define DEFAULT_SSP_REG_CR0 ( \ + GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS, 0) | \ + GEN_MASK_BITS(SSP_INTERFACE_MOTOROLA_SPI, SSP_CR0_MASK_FRF, 4) | \ + GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \ + GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \ + GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) \ +) + +/* ST versions have slightly different bit layout */ +#define DEFAULT_SSP_REG_CR0_ST ( \ + GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS_ST, 0) | \ + GEN_MASK_BITS(SSP_MICROWIRE_CHANNEL_FULL_DUPLEX, SSP_CR0_MASK_HALFDUP_ST, 5) | \ + GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \ + GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \ + GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) | \ + GEN_MASK_BITS(SSP_BITS_8, SSP_CR0_MASK_CSS_ST, 16) | \ + GEN_MASK_BITS(SSP_INTERFACE_MOTOROLA_SPI, SSP_CR0_MASK_FRF_ST, 21) \ +) + +/* The PL023 version is slightly different again */ +#define DEFAULT_SSP_REG_CR0_ST_PL023 ( \ + GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS_ST, 0) | \ + GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \ + GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \ + GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) \ +) + +#define DEFAULT_SSP_REG_CR1 ( \ + GEN_MASK_BITS(LOOPBACK_DISABLED, SSP_CR1_MASK_LBM, 0) | \ + GEN_MASK_BITS(SSP_DISABLED, SSP_CR1_MASK_SSE, 1) | \ + GEN_MASK_BITS(SSP_MASTER, SSP_CR1_MASK_MS, 2) | \ + GEN_MASK_BITS(DO_NOT_DRIVE_TX, SSP_CR1_MASK_SOD, 3) \ +) + +/* ST versions extend this register to use all 16 bits */ +#define DEFAULT_SSP_REG_CR1_ST ( \ + DEFAULT_SSP_REG_CR1 | \ + GEN_MASK_BITS(SSP_RX_MSB, SSP_CR1_MASK_RENDN_ST, 4) | \ + GEN_MASK_BITS(SSP_TX_MSB, SSP_CR1_MASK_TENDN_ST, 5) | \ + GEN_MASK_BITS(SSP_MWIRE_WAIT_ZERO, SSP_CR1_MASK_MWAIT_ST, 6) |\ + GEN_MASK_BITS(SSP_RX_1_OR_MORE_ELEM, SSP_CR1_MASK_RXIFLSEL_ST, 7) | \ + GEN_MASK_BITS(SSP_TX_1_OR_MORE_EMPTY_LOC, SSP_CR1_MASK_TXIFLSEL_ST, 10) \ +) + +/* + * The PL023 variant has further differences: no loopback mode, no microwire + * support, and a new clock feedback delay setting. + */ +#define DEFAULT_SSP_REG_CR1_ST_PL023 ( \ + GEN_MASK_BITS(SSP_DISABLED, SSP_CR1_MASK_SSE, 1) | \ + GEN_MASK_BITS(SSP_MASTER, SSP_CR1_MASK_MS, 2) | \ + GEN_MASK_BITS(DO_NOT_DRIVE_TX, SSP_CR1_MASK_SOD, 3) | \ + GEN_MASK_BITS(SSP_RX_MSB, SSP_CR1_MASK_RENDN_ST, 4) | \ + GEN_MASK_BITS(SSP_TX_MSB, SSP_CR1_MASK_TENDN_ST, 5) | \ + GEN_MASK_BITS(SSP_RX_1_OR_MORE_ELEM, SSP_CR1_MASK_RXIFLSEL_ST, 7) | \ + GEN_MASK_BITS(SSP_TX_1_OR_MORE_EMPTY_LOC, SSP_CR1_MASK_TXIFLSEL_ST, 10) | \ + GEN_MASK_BITS(SSP_FEEDBACK_CLK_DELAY_NONE, SSP_CR1_MASK_FBCLKDEL_ST, 13) \ +) + +#define DEFAULT_SSP_REG_CPSR ( \ + GEN_MASK_BITS(SSP_DEFAULT_PRESCALE, SSP_CPSR_MASK_CPSDVSR, 0) \ +) + +#define DEFAULT_SSP_REG_DMACR (\ + GEN_MASK_BITS(SSP_DMA_DISABLED, SSP_DMACR_MASK_RXDMAE, 0) | \ + GEN_MASK_BITS(SSP_DMA_DISABLED, SSP_DMACR_MASK_TXDMAE, 1) \ +) + +/** + * load_ssp_default_config - Load default configuration for SSP + * @pl022: SSP driver private data structure + */ +static void load_ssp_default_config(struct pl022 *pl022) +{ + if (pl022->vendor->pl023) { + writel(DEFAULT_SSP_REG_CR0_ST_PL023, SSP_CR0(pl022->virtbase)); + writew(DEFAULT_SSP_REG_CR1_ST_PL023, SSP_CR1(pl022->virtbase)); + } else if (pl022->vendor->extended_cr) { + writel(DEFAULT_SSP_REG_CR0_ST, SSP_CR0(pl022->virtbase)); + writew(DEFAULT_SSP_REG_CR1_ST, SSP_CR1(pl022->virtbase)); + } else { + writew(DEFAULT_SSP_REG_CR0, SSP_CR0(pl022->virtbase)); + writew(DEFAULT_SSP_REG_CR1, SSP_CR1(pl022->virtbase)); + } + writew(DEFAULT_SSP_REG_DMACR, SSP_DMACR(pl022->virtbase)); + writew(DEFAULT_SSP_REG_CPSR, SSP_CPSR(pl022->virtbase)); + writew(DISABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase)); + writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase)); +} + +/** + * This will write to TX and read from RX according to the parameters + * set in pl022. + */ +static void readwriter(struct pl022 *pl022) +{ + + /* + * The FIFO depth is different between primecell variants. + * I believe filling in too much in the FIFO might cause + * errons in 8bit wide transfers on ARM variants (just 8 words + * FIFO, means only 8x8 = 64 bits in FIFO) at least. + * + * To prevent this issue, the TX FIFO is only filled to the + * unused RX FIFO fill length, regardless of what the TX + * FIFO status flag indicates. + */ + dev_dbg(&pl022->adev->dev, + "%s, rx: %p, rxend: %p, tx: %p, txend: %p\n", + __func__, pl022->rx, pl022->rx_end, pl022->tx, pl022->tx_end); + + /* Read as much as you can */ + while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE) + && (pl022->rx < pl022->rx_end)) { + switch (pl022->read) { + case READING_NULL: + readw(SSP_DR(pl022->virtbase)); + break; + case READING_U8: + *(u8 *) (pl022->rx) = + readw(SSP_DR(pl022->virtbase)) & 0xFFU; + break; + case READING_U16: + *(u16 *) (pl022->rx) = + (u16) readw(SSP_DR(pl022->virtbase)); + break; + case READING_U32: + *(u32 *) (pl022->rx) = + readl(SSP_DR(pl022->virtbase)); + break; + } + pl022->rx += (pl022->cur_chip->n_bytes); + pl022->exp_fifo_level--; + } + /* + * Write as much as possible up to the RX FIFO size + */ + while ((pl022->exp_fifo_level < pl022->vendor->fifodepth) + && (pl022->tx < pl022->tx_end)) { + switch (pl022->write) { + case WRITING_NULL: + writew(0x0, SSP_DR(pl022->virtbase)); + break; + case WRITING_U8: + writew(*(u8 *) (pl022->tx), SSP_DR(pl022->virtbase)); + break; + case WRITING_U16: + writew((*(u16 *) (pl022->tx)), SSP_DR(pl022->virtbase)); + break; + case WRITING_U32: + writel(*(u32 *) (pl022->tx), SSP_DR(pl022->virtbase)); + break; + } + pl022->tx += (pl022->cur_chip->n_bytes); + pl022->exp_fifo_level++; + /* + * This inner reader takes care of things appearing in the RX + * FIFO as we're transmitting. This will happen a lot since the + * clock starts running when you put things into the TX FIFO, + * and then things are continuously clocked into the RX FIFO. + */ + while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE) + && (pl022->rx < pl022->rx_end)) { + switch (pl022->read) { + case READING_NULL: + readw(SSP_DR(pl022->virtbase)); + break; + case READING_U8: + *(u8 *) (pl022->rx) = + readw(SSP_DR(pl022->virtbase)) & 0xFFU; + break; + case READING_U16: + *(u16 *) (pl022->rx) = + (u16) readw(SSP_DR(pl022->virtbase)); + break; + case READING_U32: + *(u32 *) (pl022->rx) = + readl(SSP_DR(pl022->virtbase)); + break; + } + pl022->rx += (pl022->cur_chip->n_bytes); + pl022->exp_fifo_level--; + } + } + /* + * When we exit here the TX FIFO should be full and the RX FIFO + * should be empty + */ +} + +/** + * next_transfer - Move to the Next transfer in the current spi message + * @pl022: SSP driver private data structure + * + * This function moves though the linked list of spi transfers in the + * current spi message and returns with the state of current spi + * message i.e whether its last transfer is done(STATE_DONE) or + * Next transfer is ready(STATE_RUNNING) + */ +static void *next_transfer(struct pl022 *pl022) +{ + struct spi_message *msg = pl022->cur_msg; + struct spi_transfer *trans = pl022->cur_transfer; + + /* Move to next transfer */ + if (trans->transfer_list.next != &msg->transfers) { + pl022->cur_transfer = + list_entry(trans->transfer_list.next, + struct spi_transfer, transfer_list); + return STATE_RUNNING; + } + return STATE_DONE; +} + +/* + * This DMA functionality is only compiled in if we have + * access to the generic DMA devices/DMA engine. + */ +#ifdef CONFIG_DMA_ENGINE +static void unmap_free_dma_scatter(struct pl022 *pl022) +{ + /* Unmap and free the SG tables */ + dma_unmap_sg(pl022->dma_tx_channel->device->dev, pl022->sgt_tx.sgl, + pl022->sgt_tx.nents, DMA_TO_DEVICE); + dma_unmap_sg(pl022->dma_rx_channel->device->dev, pl022->sgt_rx.sgl, + pl022->sgt_rx.nents, DMA_FROM_DEVICE); + sg_free_table(&pl022->sgt_rx); + sg_free_table(&pl022->sgt_tx); +} + +static void dma_callback(void *data) +{ + struct pl022 *pl022 = data; + struct spi_message *msg = pl022->cur_msg; + + BUG_ON(!pl022->sgt_rx.sgl); + +#ifdef VERBOSE_DEBUG + /* + * Optionally dump out buffers to inspect contents, this is + * good if you want to convince yourself that the loopback + * read/write contents are the same, when adopting to a new + * DMA engine. + */ + { + struct scatterlist *sg; + unsigned int i; + + dma_sync_sg_for_cpu(&pl022->adev->dev, + pl022->sgt_rx.sgl, + pl022->sgt_rx.nents, + DMA_FROM_DEVICE); + + for_each_sg(pl022->sgt_rx.sgl, sg, pl022->sgt_rx.nents, i) { + dev_dbg(&pl022->adev->dev, "SPI RX SG ENTRY: %d", i); + print_hex_dump(KERN_ERR, "SPI RX: ", + DUMP_PREFIX_OFFSET, + 16, + 1, + sg_virt(sg), + sg_dma_len(sg), + 1); + } + for_each_sg(pl022->sgt_tx.sgl, sg, pl022->sgt_tx.nents, i) { + dev_dbg(&pl022->adev->dev, "SPI TX SG ENTRY: %d", i); + print_hex_dump(KERN_ERR, "SPI TX: ", + DUMP_PREFIX_OFFSET, + 16, + 1, + sg_virt(sg), + sg_dma_len(sg), + 1); + } + } +#endif + + unmap_free_dma_scatter(pl022); + + /* Update total bytes transferred */ + msg->actual_length += pl022->cur_transfer->len; + if (pl022->cur_transfer->cs_change) + pl022_cs_control(pl022, SSP_CHIP_DESELECT); + + /* Move to next transfer */ + msg->state = next_transfer(pl022); + tasklet_schedule(&pl022->pump_transfers); +} + +static void setup_dma_scatter(struct pl022 *pl022, + void *buffer, + unsigned int length, + struct sg_table *sgtab) +{ + struct scatterlist *sg; + int bytesleft = length; + void *bufp = buffer; + int mapbytes; + int i; + + if (buffer) { + for_each_sg(sgtab->sgl, sg, sgtab->nents, i) { + /* + * If there are less bytes left than what fits + * in the current page (plus page alignment offset) + * we just feed in this, else we stuff in as much + * as we can. + */ + if (bytesleft < (PAGE_SIZE - offset_in_page(bufp))) + mapbytes = bytesleft; + else + mapbytes = PAGE_SIZE - offset_in_page(bufp); + sg_set_page(sg, virt_to_page(bufp), + mapbytes, offset_in_page(bufp)); + bufp += mapbytes; + bytesleft -= mapbytes; + dev_dbg(&pl022->adev->dev, + "set RX/TX target page @ %p, %d bytes, %d left\n", + bufp, mapbytes, bytesleft); + } + } else { + /* Map the dummy buffer on every page */ + for_each_sg(sgtab->sgl, sg, sgtab->nents, i) { + if (bytesleft < PAGE_SIZE) + mapbytes = bytesleft; + else + mapbytes = PAGE_SIZE; + sg_set_page(sg, virt_to_page(pl022->dummypage), + mapbytes, 0); + bytesleft -= mapbytes; + dev_dbg(&pl022->adev->dev, + "set RX/TX to dummy page %d bytes, %d left\n", + mapbytes, bytesleft); + + } + } + BUG_ON(bytesleft); +} + +/** + * configure_dma - configures the channels for the next transfer + * @pl022: SSP driver's private data structure + */ +static int configure_dma(struct pl022 *pl022) +{ + struct dma_slave_config rx_conf = { + .src_addr = SSP_DR(pl022->phybase), + .direction = DMA_DEV_TO_MEM, + .device_fc = false, + }; + struct dma_slave_config tx_conf = { + .dst_addr = SSP_DR(pl022->phybase), + .direction = DMA_MEM_TO_DEV, + .device_fc = false, + }; + unsigned int pages; + int ret; + int rx_sglen, tx_sglen; + struct dma_chan *rxchan = pl022->dma_rx_channel; + struct dma_chan *txchan = pl022->dma_tx_channel; + struct dma_async_tx_descriptor *rxdesc; + struct dma_async_tx_descriptor *txdesc; + + /* Check that the channels are available */ + if (!rxchan || !txchan) + return -ENODEV; + + /* + * If supplied, the DMA burstsize should equal the FIFO trigger level. + * Notice that the DMA engine uses one-to-one mapping. Since we can + * not trigger on 2 elements this needs explicit mapping rather than + * calculation. + */ + switch (pl022->rx_lev_trig) { + case SSP_RX_1_OR_MORE_ELEM: + rx_conf.src_maxburst = 1; + break; + case SSP_RX_4_OR_MORE_ELEM: + rx_conf.src_maxburst = 4; + break; + case SSP_RX_8_OR_MORE_ELEM: + rx_conf.src_maxburst = 8; + break; + case SSP_RX_16_OR_MORE_ELEM: + rx_conf.src_maxburst = 16; + break; + case SSP_RX_32_OR_MORE_ELEM: + rx_conf.src_maxburst = 32; + break; + default: + rx_conf.src_maxburst = pl022->vendor->fifodepth >> 1; + break; + } + + switch (pl022->tx_lev_trig) { + case SSP_TX_1_OR_MORE_EMPTY_LOC: + tx_conf.dst_maxburst = 1; + break; + case SSP_TX_4_OR_MORE_EMPTY_LOC: + tx_conf.dst_maxburst = 4; + break; + case SSP_TX_8_OR_MORE_EMPTY_LOC: + tx_conf.dst_maxburst = 8; + break; + case SSP_TX_16_OR_MORE_EMPTY_LOC: + tx_conf.dst_maxburst = 16; + break; + case SSP_TX_32_OR_MORE_EMPTY_LOC: + tx_conf.dst_maxburst = 32; + break; + default: + tx_conf.dst_maxburst = pl022->vendor->fifodepth >> 1; + break; + } + + switch (pl022->read) { + case READING_NULL: + /* Use the same as for writing */ + rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED; + break; + case READING_U8: + rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; + break; + case READING_U16: + rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES; + break; + case READING_U32: + rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; + break; + } + + switch (pl022->write) { + case WRITING_NULL: + /* Use the same as for reading */ + tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED; + break; + case WRITING_U8: + tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; + break; + case WRITING_U16: + tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES; + break; + case WRITING_U32: + tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; + break; + } + + /* SPI pecularity: we need to read and write the same width */ + if (rx_conf.src_addr_width == DMA_SLAVE_BUSWIDTH_UNDEFINED) + rx_conf.src_addr_width = tx_conf.dst_addr_width; + if (tx_conf.dst_addr_width == DMA_SLAVE_BUSWIDTH_UNDEFINED) + tx_conf.dst_addr_width = rx_conf.src_addr_width; + BUG_ON(rx_conf.src_addr_width != tx_conf.dst_addr_width); + + dmaengine_slave_config(rxchan, &rx_conf); + dmaengine_slave_config(txchan, &tx_conf); + + /* Create sglists for the transfers */ + pages = DIV_ROUND_UP(pl022->cur_transfer->len, PAGE_SIZE); + dev_dbg(&pl022->adev->dev, "using %d pages for transfer\n", pages); + + ret = sg_alloc_table(&pl022->sgt_rx, pages, GFP_ATOMIC); + if (ret) + goto err_alloc_rx_sg; + + ret = sg_alloc_table(&pl022->sgt_tx, pages, GFP_ATOMIC); + if (ret) + goto err_alloc_tx_sg; + + /* Fill in the scatterlists for the RX+TX buffers */ + setup_dma_scatter(pl022, pl022->rx, + pl022->cur_transfer->len, &pl022->sgt_rx); + setup_dma_scatter(pl022, pl022->tx, + pl022->cur_transfer->len, &pl022->sgt_tx); + + /* Map DMA buffers */ + rx_sglen = dma_map_sg(rxchan->device->dev, pl022->sgt_rx.sgl, + pl022->sgt_rx.nents, DMA_FROM_DEVICE); + if (!rx_sglen) + goto err_rx_sgmap; + + tx_sglen = dma_map_sg(txchan->device->dev, pl022->sgt_tx.sgl, + pl022->sgt_tx.nents, DMA_TO_DEVICE); + if (!tx_sglen) + goto err_tx_sgmap; + + /* Send both scatterlists */ + rxdesc = dmaengine_prep_slave_sg(rxchan, + pl022->sgt_rx.sgl, + rx_sglen, + DMA_DEV_TO_MEM, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + if (!rxdesc) + goto err_rxdesc; + + txdesc = dmaengine_prep_slave_sg(txchan, + pl022->sgt_tx.sgl, + tx_sglen, + DMA_MEM_TO_DEV, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + if (!txdesc) + goto err_txdesc; + + /* Put the callback on the RX transfer only, that should finish last */ + rxdesc->callback = dma_callback; + rxdesc->callback_param = pl022; + + /* Submit and fire RX and TX with TX last so we're ready to read! */ + dmaengine_submit(rxdesc); + dmaengine_submit(txdesc); + dma_async_issue_pending(rxchan); + dma_async_issue_pending(txchan); + pl022->dma_running = true; + + return 0; + +err_txdesc: + dmaengine_terminate_all(txchan); +err_rxdesc: + dmaengine_terminate_all(rxchan); + dma_unmap_sg(txchan->device->dev, pl022->sgt_tx.sgl, + pl022->sgt_tx.nents, DMA_TO_DEVICE); +err_tx_sgmap: + dma_unmap_sg(rxchan->device->dev, pl022->sgt_rx.sgl, + pl022->sgt_rx.nents, DMA_FROM_DEVICE); +err_rx_sgmap: + sg_free_table(&pl022->sgt_tx); +err_alloc_tx_sg: + sg_free_table(&pl022->sgt_rx); +err_alloc_rx_sg: + return -ENOMEM; +} + +static int pl022_dma_probe(struct pl022 *pl022) +{ + dma_cap_mask_t mask; + + /* Try to acquire a generic DMA engine slave channel */ + dma_cap_zero(mask); + dma_cap_set(DMA_SLAVE, mask); + /* + * We need both RX and TX channels to do DMA, else do none + * of them. + */ + pl022->dma_rx_channel = dma_request_channel(mask, + pl022->master_info->dma_filter, + pl022->master_info->dma_rx_param); + if (!pl022->dma_rx_channel) { + dev_dbg(&pl022->adev->dev, "no RX DMA channel!\n"); + goto err_no_rxchan; + } + + pl022->dma_tx_channel = dma_request_channel(mask, + pl022->master_info->dma_filter, + pl022->master_info->dma_tx_param); + if (!pl022->dma_tx_channel) { + dev_dbg(&pl022->adev->dev, "no TX DMA channel!\n"); + goto err_no_txchan; + } + + pl022->dummypage = kmalloc(PAGE_SIZE, GFP_KERNEL); + if (!pl022->dummypage) + goto err_no_dummypage; + + dev_info(&pl022->adev->dev, "setup for DMA on RX %s, TX %s\n", + dma_chan_name(pl022->dma_rx_channel), + dma_chan_name(pl022->dma_tx_channel)); + + return 0; + +err_no_dummypage: + dma_release_channel(pl022->dma_tx_channel); +err_no_txchan: + dma_release_channel(pl022->dma_rx_channel); + pl022->dma_rx_channel = NULL; +err_no_rxchan: + dev_err(&pl022->adev->dev, + "Failed to work in dma mode, work without dma!\n"); + return -ENODEV; +} + +static int pl022_dma_autoprobe(struct pl022 *pl022) +{ + struct device *dev = &pl022->adev->dev; + + /* automatically configure DMA channels from platform, normally using DT */ + pl022->dma_rx_channel = dma_request_slave_channel(dev, "rx"); + if (!pl022->dma_rx_channel) + goto err_no_rxchan; + + pl022->dma_tx_channel = dma_request_slave_channel(dev, "tx"); + if (!pl022->dma_tx_channel) + goto err_no_txchan; + + pl022->dummypage = kmalloc(PAGE_SIZE, GFP_KERNEL); + if (!pl022->dummypage) + goto err_no_dummypage; + + return 0; + +err_no_dummypage: + dma_release_channel(pl022->dma_tx_channel); + pl022->dma_tx_channel = NULL; +err_no_txchan: + dma_release_channel(pl022->dma_rx_channel); + pl022->dma_rx_channel = NULL; +err_no_rxchan: + return -ENODEV; +} + +static void terminate_dma(struct pl022 *pl022) +{ + struct dma_chan *rxchan = pl022->dma_rx_channel; + struct dma_chan *txchan = pl022->dma_tx_channel; + + dmaengine_terminate_all(rxchan); + dmaengine_terminate_all(txchan); + unmap_free_dma_scatter(pl022); + pl022->dma_running = false; +} + +static void pl022_dma_remove(struct pl022 *pl022) +{ + if (pl022->dma_running) + terminate_dma(pl022); + if (pl022->dma_tx_channel) + dma_release_channel(pl022->dma_tx_channel); + if (pl022->dma_rx_channel) + dma_release_channel(pl022->dma_rx_channel); + kfree(pl022->dummypage); +} + +#else +static inline int configure_dma(struct pl022 *pl022) +{ + return -ENODEV; +} + +static inline int pl022_dma_autoprobe(struct pl022 *pl022) +{ + return 0; +} + +static inline int pl022_dma_probe(struct pl022 *pl022) +{ + return 0; +} + +static inline void pl022_dma_remove(struct pl022 *pl022) +{ +} +#endif + +/** + * pl022_interrupt_handler - Interrupt handler for SSP controller + * + * This function handles interrupts generated for an interrupt based transfer. + * If a receive overrun (ROR) interrupt is there then we disable SSP, flag the + * current message's state as STATE_ERROR and schedule the tasklet + * pump_transfers which will do the postprocessing of the current message by + * calling giveback(). Otherwise it reads data from RX FIFO till there is no + * more data, and writes data in TX FIFO till it is not full. If we complete + * the transfer we move to the next transfer and schedule the tasklet. + */ +static irqreturn_t pl022_interrupt_handler(int irq, void *dev_id) +{ + struct pl022 *pl022 = dev_id; + struct spi_message *msg = pl022->cur_msg; + u16 irq_status = 0; + + if (unlikely(!msg)) { + dev_err(&pl022->adev->dev, + "bad message state in interrupt handler"); + /* Never fail */ + return IRQ_HANDLED; + } + + /* Read the Interrupt Status Register */ + irq_status = readw(SSP_MIS(pl022->virtbase)); + + if (unlikely(!irq_status)) + return IRQ_NONE; + + /* + * This handles the FIFO interrupts, the timeout + * interrupts are flatly ignored, they cannot be + * trusted. + */ + if (unlikely(irq_status & SSP_MIS_MASK_RORMIS)) { + /* + * Overrun interrupt - bail out since our Data has been + * corrupted + */ + dev_err(&pl022->adev->dev, "FIFO overrun\n"); + if (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RFF) + dev_err(&pl022->adev->dev, + "RXFIFO is full\n"); + + /* + * Disable and clear interrupts, disable SSP, + * mark message with bad status so it can be + * retried. + */ + writew(DISABLE_ALL_INTERRUPTS, + SSP_IMSC(pl022->virtbase)); + writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase)); + writew((readw(SSP_CR1(pl022->virtbase)) & + (~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase)); + msg->state = STATE_ERROR; + + /* Schedule message queue handler */ + tasklet_schedule(&pl022->pump_transfers); + return IRQ_HANDLED; + } + + readwriter(pl022); + + if (pl022->tx == pl022->tx_end) { + /* Disable Transmit interrupt, enable receive interrupt */ + writew((readw(SSP_IMSC(pl022->virtbase)) & + ~SSP_IMSC_MASK_TXIM) | SSP_IMSC_MASK_RXIM, + SSP_IMSC(pl022->virtbase)); + } + + /* + * Since all transactions must write as much as shall be read, + * we can conclude the entire transaction once RX is complete. + * At this point, all TX will always be finished. + */ + if (pl022->rx >= pl022->rx_end) { + writew(DISABLE_ALL_INTERRUPTS, + SSP_IMSC(pl022->virtbase)); + writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase)); + if (unlikely(pl022->rx > pl022->rx_end)) { + dev_warn(&pl022->adev->dev, "read %u surplus " + "bytes (did you request an odd " + "number of bytes on a 16bit bus?)\n", + (u32) (pl022->rx - pl022->rx_end)); + } + /* Update total bytes transferred */ + msg->actual_length += pl022->cur_transfer->len; + if (pl022->cur_transfer->cs_change) + pl022_cs_control(pl022, SSP_CHIP_DESELECT); + /* Move to next transfer */ + msg->state = next_transfer(pl022); + tasklet_schedule(&pl022->pump_transfers); + return IRQ_HANDLED; + } + + return IRQ_HANDLED; +} + +/** + * This sets up the pointers to memory for the next message to + * send out on the SPI bus. + */ +static int set_up_next_transfer(struct pl022 *pl022, + struct spi_transfer *transfer) +{ + int residue; + + /* Sanity check the message for this bus width */ + residue = pl022->cur_transfer->len % pl022->cur_chip->n_bytes; + if (unlikely(residue != 0)) { + dev_err(&pl022->adev->dev, + "message of %u bytes to transmit but the current " + "chip bus has a data width of %u bytes!\n", + pl022->cur_transfer->len, + pl022->cur_chip->n_bytes); + dev_err(&pl022->adev->dev, "skipping this message\n"); + return -EIO; + } + pl022->tx = (void *)transfer->tx_buf; + pl022->tx_end = pl022->tx + pl022->cur_transfer->len; + pl022->rx = (void *)transfer->rx_buf; + pl022->rx_end = pl022->rx + pl022->cur_transfer->len; + pl022->write = + pl022->tx ? pl022->cur_chip->write : WRITING_NULL; + pl022->read = pl022->rx ? pl022->cur_chip->read : READING_NULL; + return 0; +} + +/** + * pump_transfers - Tasklet function which schedules next transfer + * when running in interrupt or DMA transfer mode. + * @data: SSP driver private data structure + * + */ +static void pump_transfers(unsigned long data) +{ + struct pl022 *pl022 = (struct pl022 *) data; + struct spi_message *message = NULL; + struct spi_transfer *transfer = NULL; + struct spi_transfer *previous = NULL; + + /* Get current state information */ + message = pl022->cur_msg; + transfer = pl022->cur_transfer; + + /* Handle for abort */ + if (message->state == STATE_ERROR) { + message->status = -EIO; + giveback(pl022); + return; + } + + /* Handle end of message */ + if (message->state == STATE_DONE) { + message->status = 0; + giveback(pl022); + return; + } + + /* Delay if requested at end of transfer before CS change */ + if (message->state == STATE_RUNNING) { + previous = list_entry(transfer->transfer_list.prev, + struct spi_transfer, + transfer_list); + if (previous->delay_usecs) + /* + * FIXME: This runs in interrupt context. + * Is this really smart? + */ + udelay(previous->delay_usecs); + + /* Reselect chip select only if cs_change was requested */ + if (previous->cs_change) + pl022_cs_control(pl022, SSP_CHIP_SELECT); + } else { + /* STATE_START */ + message->state = STATE_RUNNING; + } + + if (set_up_next_transfer(pl022, transfer)) { + message->state = STATE_ERROR; + message->status = -EIO; + giveback(pl022); + return; + } + /* Flush the FIFOs and let's go! */ + flush(pl022); + + if (pl022->cur_chip->enable_dma) { + if (configure_dma(pl022)) { + dev_dbg(&pl022->adev->dev, + "configuration of DMA failed, fall back to interrupt mode\n"); + goto err_config_dma; + } + return; + } + +err_config_dma: + /* enable all interrupts except RX */ + writew(ENABLE_ALL_INTERRUPTS & ~SSP_IMSC_MASK_RXIM, SSP_IMSC(pl022->virtbase)); +} + +static void do_interrupt_dma_transfer(struct pl022 *pl022) +{ + /* + * Default is to enable all interrupts except RX - + * this will be enabled once TX is complete + */ + u32 irqflags = (u32)(ENABLE_ALL_INTERRUPTS & ~SSP_IMSC_MASK_RXIM); + + /* Enable target chip, if not already active */ + if (!pl022->next_msg_cs_active) + pl022_cs_control(pl022, SSP_CHIP_SELECT); + + if (set_up_next_transfer(pl022, pl022->cur_transfer)) { + /* Error path */ + pl022->cur_msg->state = STATE_ERROR; + pl022->cur_msg->status = -EIO; + giveback(pl022); + return; + } + /* If we're using DMA, set up DMA here */ + if (pl022->cur_chip->enable_dma) { + /* Configure DMA transfer */ + if (configure_dma(pl022)) { + dev_dbg(&pl022->adev->dev, + "configuration of DMA failed, fall back to interrupt mode\n"); + goto err_config_dma; + } + /* Disable interrupts in DMA mode, IRQ from DMA controller */ + irqflags = DISABLE_ALL_INTERRUPTS; + } +err_config_dma: + /* Enable SSP, turn on interrupts */ + writew((readw(SSP_CR1(pl022->virtbase)) | SSP_CR1_MASK_SSE), + SSP_CR1(pl022->virtbase)); + writew(irqflags, SSP_IMSC(pl022->virtbase)); +} + +static void do_polling_transfer(struct pl022 *pl022) +{ + struct spi_message *message = NULL; + struct spi_transfer *transfer = NULL; + struct spi_transfer *previous = NULL; + struct chip_data *chip; + unsigned long time, timeout; + + chip = pl022->cur_chip; + message = pl022->cur_msg; + + while (message->state != STATE_DONE) { + /* Handle for abort */ + if (message->state == STATE_ERROR) + break; + transfer = pl022->cur_transfer; + + /* Delay if requested at end of transfer */ + if (message->state == STATE_RUNNING) { + previous = + list_entry(transfer->transfer_list.prev, + struct spi_transfer, transfer_list); + if (previous->delay_usecs) + udelay(previous->delay_usecs); + if (previous->cs_change) + pl022_cs_control(pl022, SSP_CHIP_SELECT); + } else { + /* STATE_START */ + message->state = STATE_RUNNING; + if (!pl022->next_msg_cs_active) + pl022_cs_control(pl022, SSP_CHIP_SELECT); + } + + /* Configuration Changing Per Transfer */ + if (set_up_next_transfer(pl022, transfer)) { + /* Error path */ + message->state = STATE_ERROR; + break; + } + /* Flush FIFOs and enable SSP */ + flush(pl022); + writew((readw(SSP_CR1(pl022->virtbase)) | SSP_CR1_MASK_SSE), + SSP_CR1(pl022->virtbase)); + + dev_dbg(&pl022->adev->dev, "polling transfer ongoing ...\n"); + + timeout = jiffies + msecs_to_jiffies(SPI_POLLING_TIMEOUT); + while (pl022->tx < pl022->tx_end || pl022->rx < pl022->rx_end) { + time = jiffies; + readwriter(pl022); + if (time_after(time, timeout)) { + dev_warn(&pl022->adev->dev, + "%s: timeout!\n", __func__); + message->state = STATE_ERROR; + goto out; + } + cpu_relax(); + } + + /* Update total byte transferred */ + message->actual_length += pl022->cur_transfer->len; + if (pl022->cur_transfer->cs_change) + pl022_cs_control(pl022, SSP_CHIP_DESELECT); + /* Move to next transfer */ + message->state = next_transfer(pl022); + } +out: + /* Handle end of message */ + if (message->state == STATE_DONE) + message->status = 0; + else + message->status = -EIO; + + giveback(pl022); + return; +} + +static int pl022_transfer_one_message(struct spi_master *master, + struct spi_message *msg) +{ + struct pl022 *pl022 = spi_master_get_devdata(master); + + /* Initial message state */ + pl022->cur_msg = msg; + msg->state = STATE_START; + + pl022->cur_transfer = list_entry(msg->transfers.next, + struct spi_transfer, transfer_list); + + /* Setup the SPI using the per chip configuration */ + pl022->cur_chip = spi_get_ctldata(msg->spi); + pl022->cur_cs = pl022->chipselects[msg->spi->chip_select]; + + restore_state(pl022); + flush(pl022); + + if (pl022->cur_chip->xfer_type == POLLING_TRANSFER) + do_polling_transfer(pl022); + else + do_interrupt_dma_transfer(pl022); + + return 0; +} + +static int pl022_unprepare_transfer_hardware(struct spi_master *master) +{ + struct pl022 *pl022 = spi_master_get_devdata(master); + + /* nothing more to do - disable spi/ssp and power off */ + writew((readw(SSP_CR1(pl022->virtbase)) & + (~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase)); + + return 0; +} + +static int verify_controller_parameters(struct pl022 *pl022, + struct pl022_config_chip const *chip_info) +{ + if ((chip_info->iface < SSP_INTERFACE_MOTOROLA_SPI) + || (chip_info->iface > SSP_INTERFACE_UNIDIRECTIONAL)) { + dev_err(&pl022->adev->dev, + "interface is configured incorrectly\n"); + return -EINVAL; + } + if ((chip_info->iface == SSP_INTERFACE_UNIDIRECTIONAL) && + (!pl022->vendor->unidir)) { + dev_err(&pl022->adev->dev, + "unidirectional mode not supported in this " + "hardware version\n"); + return -EINVAL; + } + if ((chip_info->hierarchy != SSP_MASTER) + && (chip_info->hierarchy != SSP_SLAVE)) { + dev_err(&pl022->adev->dev, + "hierarchy is configured incorrectly\n"); + return -EINVAL; + } + if ((chip_info->com_mode != INTERRUPT_TRANSFER) + && (chip_info->com_mode != DMA_TRANSFER) + && (chip_info->com_mode != POLLING_TRANSFER)) { + dev_err(&pl022->adev->dev, + "Communication mode is configured incorrectly\n"); + return -EINVAL; + } + switch (chip_info->rx_lev_trig) { + case SSP_RX_1_OR_MORE_ELEM: + case SSP_RX_4_OR_MORE_ELEM: + case SSP_RX_8_OR_MORE_ELEM: + /* These are always OK, all variants can handle this */ + break; + case SSP_RX_16_OR_MORE_ELEM: + if (pl022->vendor->fifodepth < 16) { + dev_err(&pl022->adev->dev, + "RX FIFO Trigger Level is configured incorrectly\n"); + return -EINVAL; + } + break; + case SSP_RX_32_OR_MORE_ELEM: + if (pl022->vendor->fifodepth < 32) { + dev_err(&pl022->adev->dev, + "RX FIFO Trigger Level is configured incorrectly\n"); + return -EINVAL; + } + break; + default: + dev_err(&pl022->adev->dev, + "RX FIFO Trigger Level is configured incorrectly\n"); + return -EINVAL; + } + switch (chip_info->tx_lev_trig) { + case SSP_TX_1_OR_MORE_EMPTY_LOC: + case SSP_TX_4_OR_MORE_EMPTY_LOC: + case SSP_TX_8_OR_MORE_EMPTY_LOC: + /* These are always OK, all variants can handle this */ + break; + case SSP_TX_16_OR_MORE_EMPTY_LOC: + if (pl022->vendor->fifodepth < 16) { + dev_err(&pl022->adev->dev, + "TX FIFO Trigger Level is configured incorrectly\n"); + return -EINVAL; + } + break; + case SSP_TX_32_OR_MORE_EMPTY_LOC: + if (pl022->vendor->fifodepth < 32) { + dev_err(&pl022->adev->dev, + "TX FIFO Trigger Level is configured incorrectly\n"); + return -EINVAL; + } + break; + default: + dev_err(&pl022->adev->dev, + "TX FIFO Trigger Level is configured incorrectly\n"); + return -EINVAL; + } + if (chip_info->iface == SSP_INTERFACE_NATIONAL_MICROWIRE) { + if ((chip_info->ctrl_len < SSP_BITS_4) + || (chip_info->ctrl_len > SSP_BITS_32)) { + dev_err(&pl022->adev->dev, + "CTRL LEN is configured incorrectly\n"); + return -EINVAL; + } + if ((chip_info->wait_state != SSP_MWIRE_WAIT_ZERO) + && (chip_info->wait_state != SSP_MWIRE_WAIT_ONE)) { + dev_err(&pl022->adev->dev, + "Wait State is configured incorrectly\n"); + return -EINVAL; + } + /* Half duplex is only available in the ST Micro version */ + if (pl022->vendor->extended_cr) { + if ((chip_info->duplex != + SSP_MICROWIRE_CHANNEL_FULL_DUPLEX) + && (chip_info->duplex != + SSP_MICROWIRE_CHANNEL_HALF_DUPLEX)) { + dev_err(&pl022->adev->dev, + "Microwire duplex mode is configured incorrectly\n"); + return -EINVAL; + } + } else { + if (chip_info->duplex != SSP_MICROWIRE_CHANNEL_FULL_DUPLEX) + dev_err(&pl022->adev->dev, + "Microwire half duplex mode requested," + " but this is only available in the" + " ST version of PL022\n"); + return -EINVAL; + } + } + return 0; +} + +static inline u32 spi_rate(u32 rate, u16 cpsdvsr, u16 scr) +{ + return rate / (cpsdvsr * (1 + scr)); +} + +static int calculate_effective_freq(struct pl022 *pl022, int freq, struct + ssp_clock_params * clk_freq) +{ + /* Lets calculate the frequency parameters */ + u16 cpsdvsr = CPSDVR_MIN, scr = SCR_MIN; + u32 rate, max_tclk, min_tclk, best_freq = 0, best_cpsdvsr = 0, + best_scr = 0, tmp, found = 0; + + rate = clk_get_rate(pl022->clk); + /* cpsdvscr = 2 & scr 0 */ + max_tclk = spi_rate(rate, CPSDVR_MIN, SCR_MIN); + /* cpsdvsr = 254 & scr = 255 */ + min_tclk = spi_rate(rate, CPSDVR_MAX, SCR_MAX); + + if (freq > max_tclk) + dev_warn(&pl022->adev->dev, + "Max speed that can be programmed is %d Hz, you requested %d\n", + max_tclk, freq); + + if (freq < min_tclk) { + dev_err(&pl022->adev->dev, + "Requested frequency: %d Hz is less than minimum possible %d Hz\n", + freq, min_tclk); + return -EINVAL; + } + + /* + * best_freq will give closest possible available rate (<= requested + * freq) for all values of scr & cpsdvsr. + */ + while ((cpsdvsr <= CPSDVR_MAX) && !found) { + while (scr <= SCR_MAX) { + tmp = spi_rate(rate, cpsdvsr, scr); + + if (tmp > freq) { + /* we need lower freq */ + scr++; + continue; + } + + /* + * If found exact value, mark found and break. + * If found more closer value, update and break. + */ + if (tmp > best_freq) { + best_freq = tmp; + best_cpsdvsr = cpsdvsr; + best_scr = scr; + + if (tmp == freq) + found = 1; + } + /* + * increased scr will give lower rates, which are not + * required + */ + break; + } + cpsdvsr += 2; + scr = SCR_MIN; + } + + WARN(!best_freq, "pl022: Matching cpsdvsr and scr not found for %d Hz rate \n", + freq); + + clk_freq->cpsdvsr = (u8) (best_cpsdvsr & 0xFF); + clk_freq->scr = (u8) (best_scr & 0xFF); + dev_dbg(&pl022->adev->dev, + "SSP Target Frequency is: %u, Effective Frequency is %u\n", + freq, best_freq); + dev_dbg(&pl022->adev->dev, "SSP cpsdvsr = %d, scr = %d\n", + clk_freq->cpsdvsr, clk_freq->scr); + + return 0; +} + +/* + * A piece of default chip info unless the platform + * supplies it. + */ +static const struct pl022_config_chip pl022_default_chip_info = { + .com_mode = POLLING_TRANSFER, + .iface = SSP_INTERFACE_MOTOROLA_SPI, + .hierarchy = SSP_SLAVE, + .slave_tx_disable = DO_NOT_DRIVE_TX, + .rx_lev_trig = SSP_RX_1_OR_MORE_ELEM, + .tx_lev_trig = SSP_TX_1_OR_MORE_EMPTY_LOC, + .ctrl_len = SSP_BITS_8, + .wait_state = SSP_MWIRE_WAIT_ZERO, + .duplex = SSP_MICROWIRE_CHANNEL_FULL_DUPLEX, + .cs_control = null_cs_control, +}; + +/** + * pl022_setup - setup function registered to SPI master framework + * @spi: spi device which is requesting setup + * + * This function is registered to the SPI framework for this SPI master + * controller. If it is the first time when setup is called by this device, + * this function will initialize the runtime state for this chip and save + * the same in the device structure. Else it will update the runtime info + * with the updated chip info. Nothing is really being written to the + * controller hardware here, that is not done until the actual transfer + * commence. + */ +static int pl022_setup(struct spi_device *spi) +{ + struct pl022_config_chip const *chip_info; + struct pl022_config_chip chip_info_dt; + struct chip_data *chip; + struct ssp_clock_params clk_freq = { .cpsdvsr = 0, .scr = 0}; + int status = 0; + struct pl022 *pl022 = spi_master_get_devdata(spi->master); + unsigned int bits = spi->bits_per_word; + u32 tmp; + struct device_node *np = spi->dev.of_node; + + if (!spi->max_speed_hz) + return -EINVAL; + + /* Get controller_state if one is supplied */ + chip = spi_get_ctldata(spi); + + if (chip == NULL) { + chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL); + if (!chip) + return -ENOMEM; + dev_dbg(&spi->dev, + "allocated memory for controller's runtime state\n"); + } + + /* Get controller data if one is supplied */ + chip_info = spi->controller_data; + + if (chip_info == NULL) { + if (np) { + chip_info_dt = pl022_default_chip_info; + + chip_info_dt.hierarchy = SSP_MASTER; + of_property_read_u32(np, "pl022,interface", + &chip_info_dt.iface); + of_property_read_u32(np, "pl022,com-mode", + &chip_info_dt.com_mode); + of_property_read_u32(np, "pl022,rx-level-trig", + &chip_info_dt.rx_lev_trig); + of_property_read_u32(np, "pl022,tx-level-trig", + &chip_info_dt.tx_lev_trig); + of_property_read_u32(np, "pl022,ctrl-len", + &chip_info_dt.ctrl_len); + of_property_read_u32(np, "pl022,wait-state", + &chip_info_dt.wait_state); + of_property_read_u32(np, "pl022,duplex", + &chip_info_dt.duplex); + + chip_info = &chip_info_dt; + } else { + chip_info = &pl022_default_chip_info; + /* spi_board_info.controller_data not is supplied */ + dev_dbg(&spi->dev, + "using default controller_data settings\n"); + } + } else + dev_dbg(&spi->dev, + "using user supplied controller_data settings\n"); + + /* + * We can override with custom divisors, else we use the board + * frequency setting + */ + if ((0 == chip_info->clk_freq.cpsdvsr) + && (0 == chip_info->clk_freq.scr)) { + status = calculate_effective_freq(pl022, + spi->max_speed_hz, + &clk_freq); + if (status < 0) + goto err_config_params; + } else { + memcpy(&clk_freq, &chip_info->clk_freq, sizeof(clk_freq)); + if ((clk_freq.cpsdvsr % 2) != 0) + clk_freq.cpsdvsr = + clk_freq.cpsdvsr - 1; + } + if ((clk_freq.cpsdvsr < CPSDVR_MIN) + || (clk_freq.cpsdvsr > CPSDVR_MAX)) { + status = -EINVAL; + dev_err(&spi->dev, + "cpsdvsr is configured incorrectly\n"); + goto err_config_params; + } + + status = verify_controller_parameters(pl022, chip_info); + if (status) { + dev_err(&spi->dev, "controller data is incorrect"); + goto err_config_params; + } + + pl022->rx_lev_trig = chip_info->rx_lev_trig; + pl022->tx_lev_trig = chip_info->tx_lev_trig; + + /* Now set controller state based on controller data */ + chip->xfer_type = chip_info->com_mode; + if (!chip_info->cs_control) { + chip->cs_control = null_cs_control; + if (!gpio_is_valid(pl022->chipselects[spi->chip_select])) + dev_warn(&spi->dev, + "invalid chip select\n"); + } else + chip->cs_control = chip_info->cs_control; + + /* Check bits per word with vendor specific range */ + if ((bits <= 3) || (bits > pl022->vendor->max_bpw)) { + status = -ENOTSUPP; + dev_err(&spi->dev, "illegal data size for this controller!\n"); + dev_err(&spi->dev, "This controller can only handle 4 <= n <= %d bit words\n", + pl022->vendor->max_bpw); + goto err_config_params; + } else if (bits <= 8) { + dev_dbg(&spi->dev, "4 <= n <=8 bits per word\n"); + chip->n_bytes = 1; + chip->read = READING_U8; + chip->write = WRITING_U8; + } else if (bits <= 16) { + dev_dbg(&spi->dev, "9 <= n <= 16 bits per word\n"); + chip->n_bytes = 2; + chip->read = READING_U16; + chip->write = WRITING_U16; + } else { + dev_dbg(&spi->dev, "17 <= n <= 32 bits per word\n"); + chip->n_bytes = 4; + chip->read = READING_U32; + chip->write = WRITING_U32; + } + + /* Now Initialize all register settings required for this chip */ + chip->cr0 = 0; + chip->cr1 = 0; + chip->dmacr = 0; + chip->cpsr = 0; + if ((chip_info->com_mode == DMA_TRANSFER) + && ((pl022->master_info)->enable_dma)) { + chip->enable_dma = true; + dev_dbg(&spi->dev, "DMA mode set in controller state\n"); + SSP_WRITE_BITS(chip->dmacr, SSP_DMA_ENABLED, + SSP_DMACR_MASK_RXDMAE, 0); + SSP_WRITE_BITS(chip->dmacr, SSP_DMA_ENABLED, + SSP_DMACR_MASK_TXDMAE, 1); + } else { + chip->enable_dma = false; + dev_dbg(&spi->dev, "DMA mode NOT set in controller state\n"); + SSP_WRITE_BITS(chip->dmacr, SSP_DMA_DISABLED, + SSP_DMACR_MASK_RXDMAE, 0); + SSP_WRITE_BITS(chip->dmacr, SSP_DMA_DISABLED, + SSP_DMACR_MASK_TXDMAE, 1); + } + + chip->cpsr = clk_freq.cpsdvsr; + + /* Special setup for the ST micro extended control registers */ + if (pl022->vendor->extended_cr) { + u32 etx; + + if (pl022->vendor->pl023) { + /* These bits are only in the PL023 */ + SSP_WRITE_BITS(chip->cr1, chip_info->clkdelay, + SSP_CR1_MASK_FBCLKDEL_ST, 13); + } else { + /* These bits are in the PL022 but not PL023 */ + SSP_WRITE_BITS(chip->cr0, chip_info->duplex, + SSP_CR0_MASK_HALFDUP_ST, 5); + SSP_WRITE_BITS(chip->cr0, chip_info->ctrl_len, + SSP_CR0_MASK_CSS_ST, 16); + SSP_WRITE_BITS(chip->cr0, chip_info->iface, + SSP_CR0_MASK_FRF_ST, 21); + SSP_WRITE_BITS(chip->cr1, chip_info->wait_state, + SSP_CR1_MASK_MWAIT_ST, 6); + } + SSP_WRITE_BITS(chip->cr0, bits - 1, + SSP_CR0_MASK_DSS_ST, 0); + + if (spi->mode & SPI_LSB_FIRST) { + tmp = SSP_RX_LSB; + etx = SSP_TX_LSB; + } else { + tmp = SSP_RX_MSB; + etx = SSP_TX_MSB; + } + SSP_WRITE_BITS(chip->cr1, tmp, SSP_CR1_MASK_RENDN_ST, 4); + SSP_WRITE_BITS(chip->cr1, etx, SSP_CR1_MASK_TENDN_ST, 5); + SSP_WRITE_BITS(chip->cr1, chip_info->rx_lev_trig, + SSP_CR1_MASK_RXIFLSEL_ST, 7); + SSP_WRITE_BITS(chip->cr1, chip_info->tx_lev_trig, + SSP_CR1_MASK_TXIFLSEL_ST, 10); + } else { + SSP_WRITE_BITS(chip->cr0, bits - 1, + SSP_CR0_MASK_DSS, 0); + SSP_WRITE_BITS(chip->cr0, chip_info->iface, + SSP_CR0_MASK_FRF, 4); + } + + /* Stuff that is common for all versions */ + if (spi->mode & SPI_CPOL) + tmp = SSP_CLK_POL_IDLE_HIGH; + else + tmp = SSP_CLK_POL_IDLE_LOW; + SSP_WRITE_BITS(chip->cr0, tmp, SSP_CR0_MASK_SPO, 6); + + if (spi->mode & SPI_CPHA) + tmp = SSP_CLK_SECOND_EDGE; + else + tmp = SSP_CLK_FIRST_EDGE; + SSP_WRITE_BITS(chip->cr0, tmp, SSP_CR0_MASK_SPH, 7); + + SSP_WRITE_BITS(chip->cr0, clk_freq.scr, SSP_CR0_MASK_SCR, 8); + /* Loopback is available on all versions except PL023 */ + if (pl022->vendor->loopback) { + if (spi->mode & SPI_LOOP) + tmp = LOOPBACK_ENABLED; + else + tmp = LOOPBACK_DISABLED; + SSP_WRITE_BITS(chip->cr1, tmp, SSP_CR1_MASK_LBM, 0); + } + SSP_WRITE_BITS(chip->cr1, SSP_DISABLED, SSP_CR1_MASK_SSE, 1); + SSP_WRITE_BITS(chip->cr1, chip_info->hierarchy, SSP_CR1_MASK_MS, 2); + SSP_WRITE_BITS(chip->cr1, chip_info->slave_tx_disable, SSP_CR1_MASK_SOD, + 3); + + /* Save controller_state */ + spi_set_ctldata(spi, chip); + return status; + err_config_params: + spi_set_ctldata(spi, NULL); + kfree(chip); + return status; +} + +/** + * pl022_cleanup - cleanup function registered to SPI master framework + * @spi: spi device which is requesting cleanup + * + * This function is registered to the SPI framework for this SPI master + * controller. It will free the runtime state of chip. + */ +static void pl022_cleanup(struct spi_device *spi) +{ + struct chip_data *chip = spi_get_ctldata(spi); + + spi_set_ctldata(spi, NULL); + kfree(chip); +} + +static struct pl022_ssp_controller * +pl022_platform_data_dt_get(struct device *dev) +{ + struct device_node *np = dev->of_node; + struct pl022_ssp_controller *pd; + u32 tmp; + + if (!np) { + dev_err(dev, "no dt node defined\n"); + return NULL; + } + + pd = devm_kzalloc(dev, sizeof(struct pl022_ssp_controller), GFP_KERNEL); + if (!pd) + return NULL; + + pd->bus_id = -1; + pd->enable_dma = 1; + of_property_read_u32(np, "num-cs", &tmp); + pd->num_chipselect = tmp; + of_property_read_u32(np, "pl022,autosuspend-delay", + &pd->autosuspend_delay); + pd->rt = of_property_read_bool(np, "pl022,rt"); + + return pd; +} + +static int pl022_probe(struct amba_device *adev, const struct amba_id *id) +{ + struct device *dev = &adev->dev; + struct pl022_ssp_controller *platform_info = + dev_get_platdata(&adev->dev); + struct spi_master *master; + struct pl022 *pl022 = NULL; /*Data for this driver */ + struct device_node *np = adev->dev.of_node; + int status = 0, i, num_cs; + + dev_info(&adev->dev, + "ARM PL022 driver, device ID: 0x%08x\n", adev->periphid); + if (!platform_info && IS_ENABLED(CONFIG_OF)) + platform_info = pl022_platform_data_dt_get(dev); + + if (!platform_info) { + dev_err(dev, "probe: no platform data defined\n"); + return -ENODEV; + } + + if (platform_info->num_chipselect) { + num_cs = platform_info->num_chipselect; + } else { + dev_err(dev, "probe: no chip select defined\n"); + return -ENODEV; + } + + /* Allocate master with space for data */ + master = spi_alloc_master(dev, sizeof(struct pl022)); + if (master == NULL) { + dev_err(&adev->dev, "probe - cannot alloc SPI master\n"); + return -ENOMEM; + } + + pl022 = spi_master_get_devdata(master); + pl022->master = master; + pl022->master_info = platform_info; + pl022->adev = adev; + pl022->vendor = id->data; + pl022->chipselects = devm_kzalloc(dev, num_cs * sizeof(int), + GFP_KERNEL); + if (!pl022->chipselects) { + status = -ENOMEM; + goto err_no_mem; + } + + /* + * Bus Number Which has been Assigned to this SSP controller + * on this board + */ + master->bus_num = platform_info->bus_id; + master->num_chipselect = num_cs; + master->cleanup = pl022_cleanup; + master->setup = pl022_setup; + master->auto_runtime_pm = true; + master->transfer_one_message = pl022_transfer_one_message; + master->unprepare_transfer_hardware = pl022_unprepare_transfer_hardware; + master->rt = platform_info->rt; + master->dev.of_node = dev->of_node; + + if (platform_info->num_chipselect && platform_info->chipselects) { + for (i = 0; i < num_cs; i++) + pl022->chipselects[i] = platform_info->chipselects[i]; + } else if (pl022->vendor->internal_cs_ctrl) { + for (i = 0; i < num_cs; i++) + pl022->chipselects[i] = i; + } else if (IS_ENABLED(CONFIG_OF)) { + for (i = 0; i < num_cs; i++) { + int cs_gpio = of_get_named_gpio(np, "cs-gpios", i); + + if (cs_gpio == -EPROBE_DEFER) { + status = -EPROBE_DEFER; + goto err_no_gpio; + } + + pl022->chipselects[i] = cs_gpio; + + if (gpio_is_valid(cs_gpio)) { + if (devm_gpio_request(dev, cs_gpio, "ssp-pl022")) + dev_err(&adev->dev, + "could not request %d gpio\n", + cs_gpio); + else if (gpio_direction_output(cs_gpio, 1)) + dev_err(&adev->dev, + "could not set gpio %d as output\n", + cs_gpio); + } + } + } + + /* + * Supports mode 0-3, loopback, and active low CS. Transfers are + * always MS bit first on the original pl022. + */ + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LOOP; + if (pl022->vendor->extended_cr) + master->mode_bits |= SPI_LSB_FIRST; + + dev_dbg(&adev->dev, "BUSNO: %d\n", master->bus_num); + + status = amba_request_regions(adev, NULL); + if (status) + goto err_no_ioregion; + + pl022->phybase = adev->res.start; + pl022->virtbase = devm_ioremap(dev, adev->res.start, + resource_size(&adev->res)); + if (pl022->virtbase == NULL) { + status = -ENOMEM; + goto err_no_ioremap; + } + dev_info(&adev->dev, "mapped registers from %pa to %p\n", + &adev->res.start, pl022->virtbase); + + pl022->clk = devm_clk_get(&adev->dev, NULL); + if (IS_ERR(pl022->clk)) { + status = PTR_ERR(pl022->clk); + dev_err(&adev->dev, "could not retrieve SSP/SPI bus clock\n"); + goto err_no_clk; + } + + status = clk_prepare_enable(pl022->clk); + if (status) { + dev_err(&adev->dev, "could not enable SSP/SPI bus clock\n"); + goto err_no_clk_en; + } + + /* Initialize transfer pump */ + tasklet_init(&pl022->pump_transfers, pump_transfers, + (unsigned long)pl022); + + /* Disable SSP */ + writew((readw(SSP_CR1(pl022->virtbase)) & (~SSP_CR1_MASK_SSE)), + SSP_CR1(pl022->virtbase)); + load_ssp_default_config(pl022); + + status = devm_request_irq(dev, adev->irq[0], pl022_interrupt_handler, + 0, "pl022", pl022); + if (status < 0) { + dev_err(&adev->dev, "probe - cannot get IRQ (%d)\n", status); + goto err_no_irq; + } + + /* Get DMA channels, try autoconfiguration first */ + status = pl022_dma_autoprobe(pl022); + + /* If that failed, use channels from platform_info */ + if (status == 0) + platform_info->enable_dma = 1; + else if (platform_info->enable_dma) { + status = pl022_dma_probe(pl022); + if (status != 0) + platform_info->enable_dma = 0; + } + + /* Register with the SPI framework */ + amba_set_drvdata(adev, pl022); + status = devm_spi_register_master(&adev->dev, master); + if (status != 0) { + dev_err(&adev->dev, + "probe - problem registering spi master\n"); + goto err_spi_register; + } + dev_dbg(dev, "probe succeeded\n"); + + /* let runtime pm put suspend */ + if (platform_info->autosuspend_delay > 0) { + dev_info(&adev->dev, + "will use autosuspend for runtime pm, delay %dms\n", + platform_info->autosuspend_delay); + pm_runtime_set_autosuspend_delay(dev, + platform_info->autosuspend_delay); + pm_runtime_use_autosuspend(dev); + } + pm_runtime_put(dev); + + return 0; + + err_spi_register: + if (platform_info->enable_dma) + pl022_dma_remove(pl022); + err_no_irq: + clk_disable_unprepare(pl022->clk); + err_no_clk_en: + err_no_clk: + err_no_ioremap: + amba_release_regions(adev); + err_no_ioregion: + err_no_gpio: + err_no_mem: + spi_master_put(master); + return status; +} + +static int +pl022_remove(struct amba_device *adev) +{ + struct pl022 *pl022 = amba_get_drvdata(adev); + + if (!pl022) + return 0; + + /* + * undo pm_runtime_put() in probe. I assume that we're not + * accessing the primecell here. + */ + pm_runtime_get_noresume(&adev->dev); + + load_ssp_default_config(pl022); + if (pl022->master_info->enable_dma) + pl022_dma_remove(pl022); + + clk_disable_unprepare(pl022->clk); + amba_release_regions(adev); + tasklet_disable(&pl022->pump_transfers); + return 0; +} + +#ifdef CONFIG_PM_SLEEP +static int pl022_suspend(struct device *dev) +{ + struct pl022 *pl022 = dev_get_drvdata(dev); + int ret; + + ret = spi_master_suspend(pl022->master); + if (ret) { + dev_warn(dev, "cannot suspend master\n"); + return ret; + } + + ret = pm_runtime_force_suspend(dev); + if (ret) { + spi_master_resume(pl022->master); + return ret; + } + + pinctrl_pm_select_sleep_state(dev); + + dev_dbg(dev, "suspended\n"); + return 0; +} + +static int pl022_resume(struct device *dev) +{ + struct pl022 *pl022 = dev_get_drvdata(dev); + int ret; + + ret = pm_runtime_force_resume(dev); + if (ret) + dev_err(dev, "problem resuming\n"); + + /* Start the queue running */ + ret = spi_master_resume(pl022->master); + if (ret) + dev_err(dev, "problem starting queue (%d)\n", ret); + else + dev_dbg(dev, "resumed\n"); + + return ret; +} +#endif + +#ifdef CONFIG_PM +static int pl022_runtime_suspend(struct device *dev) +{ + struct pl022 *pl022 = dev_get_drvdata(dev); + + clk_disable_unprepare(pl022->clk); + pinctrl_pm_select_idle_state(dev); + + return 0; +} + +static int pl022_runtime_resume(struct device *dev) +{ + struct pl022 *pl022 = dev_get_drvdata(dev); + + pinctrl_pm_select_default_state(dev); + clk_prepare_enable(pl022->clk); + + return 0; +} +#endif + +static const struct dev_pm_ops pl022_dev_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(pl022_suspend, pl022_resume) + SET_RUNTIME_PM_OPS(pl022_runtime_suspend, pl022_runtime_resume, NULL) +}; + +static struct vendor_data vendor_arm = { + .fifodepth = 8, + .max_bpw = 16, + .unidir = false, + .extended_cr = false, + .pl023 = false, + .loopback = true, + .internal_cs_ctrl = false, +}; + +static struct vendor_data vendor_st = { + .fifodepth = 32, + .max_bpw = 32, + .unidir = false, + .extended_cr = true, + .pl023 = false, + .loopback = true, + .internal_cs_ctrl = false, +}; + +static struct vendor_data vendor_st_pl023 = { + .fifodepth = 32, + .max_bpw = 32, + .unidir = false, + .extended_cr = true, + .pl023 = true, + .loopback = false, + .internal_cs_ctrl = false, +}; + +static struct vendor_data vendor_lsi = { + .fifodepth = 8, + .max_bpw = 16, + .unidir = false, + .extended_cr = false, + .pl023 = false, + .loopback = true, + .internal_cs_ctrl = true, +}; + +static struct amba_id pl022_ids[] = { + { + /* + * ARM PL022 variant, this has a 16bit wide + * and 8 locations deep TX/RX FIFO + */ + .id = 0x00041022, + .mask = 0x000fffff, + .data = &vendor_arm, + }, + { + /* + * ST Micro derivative, this has 32bit wide + * and 32 locations deep TX/RX FIFO + */ + .id = 0x01080022, + .mask = 0xffffffff, + .data = &vendor_st, + }, + { + /* + * ST-Ericsson derivative "PL023" (this is not + * an official ARM number), this is a PL022 SSP block + * stripped to SPI mode only, it has 32bit wide + * and 32 locations deep TX/RX FIFO but no extended + * CR0/CR1 register + */ + .id = 0x00080023, + .mask = 0xffffffff, + .data = &vendor_st_pl023, + }, + { + /* + * PL022 variant that has a chip select control register whih + * allows control of 5 output signals nCS[0:4]. + */ + .id = 0x000b6022, + .mask = 0x000fffff, + .data = &vendor_lsi, + }, + { 0, 0 }, +}; + +MODULE_DEVICE_TABLE(amba, pl022_ids); + +static struct amba_driver pl022_driver = { + .drv = { + .name = "ssp-pl022", + .pm = &pl022_dev_pm_ops, + }, + .id_table = pl022_ids, + .probe = pl022_probe, + .remove = pl022_remove, +}; + +static int __init pl022_init(void) +{ + return amba_driver_register(&pl022_driver); +} +subsys_initcall(pl022_init); + +static void __exit pl022_exit(void) +{ + amba_driver_unregister(&pl022_driver); +} +module_exit(pl022_exit); + +MODULE_AUTHOR("Linus Walleij <linus.walleij@stericsson.com>"); +MODULE_DESCRIPTION("PL022 SSP Controller Driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/spi/spi-ppc4xx.c b/drivers/spi/spi-ppc4xx.c new file mode 100644 index 000000000..54fb984a3 --- /dev/null +++ b/drivers/spi/spi-ppc4xx.c @@ -0,0 +1,585 @@ +/* + * SPI_PPC4XX SPI controller driver. + * + * Copyright (C) 2007 Gary Jennejohn <garyj@denx.de> + * Copyright 2008 Stefan Roese <sr@denx.de>, DENX Software Engineering + * Copyright 2009 Harris Corporation, Steven A. Falco <sfalco@harris.com> + * + * Based in part on drivers/spi/spi_s3c24xx.c + * + * Copyright (c) 2006 Ben Dooks + * Copyright (c) 2006 Simtec Electronics + * Ben Dooks <ben@simtec.co.uk> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published + * by the Free Software Foundation. + */ + +/* + * The PPC4xx SPI controller has no FIFO so each sent/received byte will + * generate an interrupt to the CPU. This can cause high CPU utilization. + * This driver allows platforms to reduce the interrupt load on the CPU + * during SPI transfers by setting max_speed_hz via the device tree. + */ + +#include <linux/module.h> +#include <linux/sched.h> +#include <linux/slab.h> +#include <linux/errno.h> +#include <linux/wait.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/of_platform.h> +#include <linux/of_gpio.h> +#include <linux/interrupt.h> +#include <linux/delay.h> + +#include <linux/gpio.h> +#include <linux/spi/spi.h> +#include <linux/spi/spi_bitbang.h> + +#include <asm/io.h> +#include <asm/dcr.h> +#include <asm/dcr-regs.h> + +/* bits in mode register - bit 0 is MSb */ + +/* + * SPI_PPC4XX_MODE_SCP = 0 means "data latched on trailing edge of clock" + * SPI_PPC4XX_MODE_SCP = 1 means "data latched on leading edge of clock" + * Note: This is the inverse of CPHA. + */ +#define SPI_PPC4XX_MODE_SCP (0x80 >> 3) + +/* SPI_PPC4XX_MODE_SPE = 1 means "port enabled" */ +#define SPI_PPC4XX_MODE_SPE (0x80 >> 4) + +/* + * SPI_PPC4XX_MODE_RD = 0 means "MSB first" - this is the normal mode + * SPI_PPC4XX_MODE_RD = 1 means "LSB first" - this is bit-reversed mode + * Note: This is identical to SPI_LSB_FIRST. + */ +#define SPI_PPC4XX_MODE_RD (0x80 >> 5) + +/* + * SPI_PPC4XX_MODE_CI = 0 means "clock idles low" + * SPI_PPC4XX_MODE_CI = 1 means "clock idles high" + * Note: This is identical to CPOL. + */ +#define SPI_PPC4XX_MODE_CI (0x80 >> 6) + +/* + * SPI_PPC4XX_MODE_IL = 0 means "loopback disable" + * SPI_PPC4XX_MODE_IL = 1 means "loopback enable" + */ +#define SPI_PPC4XX_MODE_IL (0x80 >> 7) + +/* bits in control register */ +/* starts a transfer when set */ +#define SPI_PPC4XX_CR_STR (0x80 >> 7) + +/* bits in status register */ +/* port is busy with a transfer */ +#define SPI_PPC4XX_SR_BSY (0x80 >> 6) +/* RxD ready */ +#define SPI_PPC4XX_SR_RBR (0x80 >> 7) + +/* clock settings (SCP and CI) for various SPI modes */ +#define SPI_CLK_MODE0 (SPI_PPC4XX_MODE_SCP | 0) +#define SPI_CLK_MODE1 (0 | 0) +#define SPI_CLK_MODE2 (SPI_PPC4XX_MODE_SCP | SPI_PPC4XX_MODE_CI) +#define SPI_CLK_MODE3 (0 | SPI_PPC4XX_MODE_CI) + +#define DRIVER_NAME "spi_ppc4xx_of" + +struct spi_ppc4xx_regs { + u8 mode; + u8 rxd; + u8 txd; + u8 cr; + u8 sr; + u8 dummy; + /* + * Clock divisor modulus register + * This uses the following formula: + * SCPClkOut = OPBCLK/(4(CDM + 1)) + * or + * CDM = (OPBCLK/4*SCPClkOut) - 1 + * bit 0 is the MSb! + */ + u8 cdm; +}; + +/* SPI Controller driver's private data. */ +struct ppc4xx_spi { + /* bitbang has to be first */ + struct spi_bitbang bitbang; + struct completion done; + + u64 mapbase; + u64 mapsize; + int irqnum; + /* need this to set the SPI clock */ + unsigned int opb_freq; + + /* for transfers */ + int len; + int count; + /* data buffers */ + const unsigned char *tx; + unsigned char *rx; + + int *gpios; + + struct spi_ppc4xx_regs __iomem *regs; /* pointer to the registers */ + struct spi_master *master; + struct device *dev; +}; + +/* need this so we can set the clock in the chipselect routine */ +struct spi_ppc4xx_cs { + u8 mode; +}; + +static int spi_ppc4xx_txrx(struct spi_device *spi, struct spi_transfer *t) +{ + struct ppc4xx_spi *hw; + u8 data; + + dev_dbg(&spi->dev, "txrx: tx %p, rx %p, len %d\n", + t->tx_buf, t->rx_buf, t->len); + + hw = spi_master_get_devdata(spi->master); + + hw->tx = t->tx_buf; + hw->rx = t->rx_buf; + hw->len = t->len; + hw->count = 0; + + /* send the first byte */ + data = hw->tx ? hw->tx[0] : 0; + out_8(&hw->regs->txd, data); + out_8(&hw->regs->cr, SPI_PPC4XX_CR_STR); + wait_for_completion(&hw->done); + + return hw->count; +} + +static int spi_ppc4xx_setupxfer(struct spi_device *spi, struct spi_transfer *t) +{ + struct ppc4xx_spi *hw = spi_master_get_devdata(spi->master); + struct spi_ppc4xx_cs *cs = spi->controller_state; + int scr; + u8 cdm = 0; + u32 speed; + u8 bits_per_word; + + /* Start with the generic configuration for this device. */ + bits_per_word = spi->bits_per_word; + speed = spi->max_speed_hz; + + /* + * Modify the configuration if the transfer overrides it. Do not allow + * the transfer to overwrite the generic configuration with zeros. + */ + if (t) { + if (t->bits_per_word) + bits_per_word = t->bits_per_word; + + if (t->speed_hz) + speed = min(t->speed_hz, spi->max_speed_hz); + } + + if (!speed || (speed > spi->max_speed_hz)) { + dev_err(&spi->dev, "invalid speed_hz (%d)\n", speed); + return -EINVAL; + } + + /* Write new configuration */ + out_8(&hw->regs->mode, cs->mode); + + /* Set the clock */ + /* opb_freq was already divided by 4 */ + scr = (hw->opb_freq / speed) - 1; + if (scr > 0) + cdm = min(scr, 0xff); + + dev_dbg(&spi->dev, "setting pre-scaler to %d (hz %d)\n", cdm, speed); + + if (in_8(&hw->regs->cdm) != cdm) + out_8(&hw->regs->cdm, cdm); + + spin_lock(&hw->bitbang.lock); + if (!hw->bitbang.busy) { + hw->bitbang.chipselect(spi, BITBANG_CS_INACTIVE); + /* Need to ndelay here? */ + } + spin_unlock(&hw->bitbang.lock); + + return 0; +} + +static int spi_ppc4xx_setup(struct spi_device *spi) +{ + struct spi_ppc4xx_cs *cs = spi->controller_state; + + if (!spi->max_speed_hz) { + dev_err(&spi->dev, "invalid max_speed_hz (must be non-zero)\n"); + return -EINVAL; + } + + if (cs == NULL) { + cs = kzalloc(sizeof *cs, GFP_KERNEL); + if (!cs) + return -ENOMEM; + spi->controller_state = cs; + } + + /* + * We set all bits of the SPI0_MODE register, so, + * no need to read-modify-write + */ + cs->mode = SPI_PPC4XX_MODE_SPE; + + switch (spi->mode & (SPI_CPHA | SPI_CPOL)) { + case SPI_MODE_0: + cs->mode |= SPI_CLK_MODE0; + break; + case SPI_MODE_1: + cs->mode |= SPI_CLK_MODE1; + break; + case SPI_MODE_2: + cs->mode |= SPI_CLK_MODE2; + break; + case SPI_MODE_3: + cs->mode |= SPI_CLK_MODE3; + break; + } + + if (spi->mode & SPI_LSB_FIRST) + cs->mode |= SPI_PPC4XX_MODE_RD; + + return 0; +} + +static void spi_ppc4xx_chipsel(struct spi_device *spi, int value) +{ + struct ppc4xx_spi *hw = spi_master_get_devdata(spi->master); + unsigned int cs = spi->chip_select; + unsigned int cspol; + + /* + * If there are no chip selects at all, or if this is the special + * case of a non-existent (dummy) chip select, do nothing. + */ + + if (!hw->master->num_chipselect || hw->gpios[cs] == -EEXIST) + return; + + cspol = spi->mode & SPI_CS_HIGH ? 1 : 0; + if (value == BITBANG_CS_INACTIVE) + cspol = !cspol; + + gpio_set_value(hw->gpios[cs], cspol); +} + +static irqreturn_t spi_ppc4xx_int(int irq, void *dev_id) +{ + struct ppc4xx_spi *hw; + u8 status; + u8 data; + unsigned int count; + + hw = (struct ppc4xx_spi *)dev_id; + + status = in_8(&hw->regs->sr); + if (!status) + return IRQ_NONE; + + /* + * BSY de-asserts one cycle after the transfer is complete. The + * interrupt is asserted after the transfer is complete. The exact + * relationship is not documented, hence this code. + */ + + if (unlikely(status & SPI_PPC4XX_SR_BSY)) { + u8 lstatus; + int cnt = 0; + + dev_dbg(hw->dev, "got interrupt but spi still busy?\n"); + do { + ndelay(10); + lstatus = in_8(&hw->regs->sr); + } while (++cnt < 100 && lstatus & SPI_PPC4XX_SR_BSY); + + if (cnt >= 100) { + dev_err(hw->dev, "busywait: too many loops!\n"); + complete(&hw->done); + return IRQ_HANDLED; + } else { + /* status is always 1 (RBR) here */ + status = in_8(&hw->regs->sr); + dev_dbg(hw->dev, "loops %d status %x\n", cnt, status); + } + } + + count = hw->count; + hw->count++; + + /* RBR triggered this interrupt. Therefore, data must be ready. */ + data = in_8(&hw->regs->rxd); + if (hw->rx) + hw->rx[count] = data; + + count++; + + if (count < hw->len) { + data = hw->tx ? hw->tx[count] : 0; + out_8(&hw->regs->txd, data); + out_8(&hw->regs->cr, SPI_PPC4XX_CR_STR); + } else { + complete(&hw->done); + } + + return IRQ_HANDLED; +} + +static void spi_ppc4xx_cleanup(struct spi_device *spi) +{ + kfree(spi->controller_state); +} + +static void spi_ppc4xx_enable(struct ppc4xx_spi *hw) +{ + /* + * On all 4xx PPC's the SPI bus is shared/multiplexed with + * the 2nd I2C bus. We need to enable the the SPI bus before + * using it. + */ + + /* need to clear bit 14 to enable SPC */ + dcri_clrset(SDR0, SDR0_PFC1, 0x80000000 >> 14, 0); +} + +static void free_gpios(struct ppc4xx_spi *hw) +{ + if (hw->master->num_chipselect) { + int i; + for (i = 0; i < hw->master->num_chipselect; i++) + if (gpio_is_valid(hw->gpios[i])) + gpio_free(hw->gpios[i]); + + kfree(hw->gpios); + hw->gpios = NULL; + } +} + +/* + * platform_device layer stuff... + */ +static int spi_ppc4xx_of_probe(struct platform_device *op) +{ + struct ppc4xx_spi *hw; + struct spi_master *master; + struct spi_bitbang *bbp; + struct resource resource; + struct device_node *np = op->dev.of_node; + struct device *dev = &op->dev; + struct device_node *opbnp; + int ret; + int num_gpios; + const unsigned int *clk; + + master = spi_alloc_master(dev, sizeof *hw); + if (master == NULL) + return -ENOMEM; + master->dev.of_node = np; + platform_set_drvdata(op, master); + hw = spi_master_get_devdata(master); + hw->master = master; + hw->dev = dev; + + init_completion(&hw->done); + + /* + * A count of zero implies a single SPI device without any chip-select. + * Note that of_gpio_count counts all gpios assigned to this spi master. + * This includes both "null" gpio's and real ones. + */ + num_gpios = of_gpio_count(np); + if (num_gpios > 0) { + int i; + + hw->gpios = kzalloc(sizeof(int) * num_gpios, GFP_KERNEL); + if (!hw->gpios) { + ret = -ENOMEM; + goto free_master; + } + + for (i = 0; i < num_gpios; i++) { + int gpio; + enum of_gpio_flags flags; + + gpio = of_get_gpio_flags(np, i, &flags); + hw->gpios[i] = gpio; + + if (gpio_is_valid(gpio)) { + /* Real CS - set the initial state. */ + ret = gpio_request(gpio, np->name); + if (ret < 0) { + dev_err(dev, "can't request gpio " + "#%d: %d\n", i, ret); + goto free_gpios; + } + + gpio_direction_output(gpio, + !!(flags & OF_GPIO_ACTIVE_LOW)); + } else if (gpio == -EEXIST) { + ; /* No CS, but that's OK. */ + } else { + dev_err(dev, "invalid gpio #%d: %d\n", i, gpio); + ret = -EINVAL; + goto free_gpios; + } + } + } + + /* Setup the state for the bitbang driver */ + bbp = &hw->bitbang; + bbp->master = hw->master; + bbp->setup_transfer = spi_ppc4xx_setupxfer; + bbp->chipselect = spi_ppc4xx_chipsel; + bbp->txrx_bufs = spi_ppc4xx_txrx; + bbp->use_dma = 0; + bbp->master->setup = spi_ppc4xx_setup; + bbp->master->cleanup = spi_ppc4xx_cleanup; + bbp->master->bits_per_word_mask = SPI_BPW_MASK(8); + + /* the spi->mode bits understood by this driver: */ + bbp->master->mode_bits = + SPI_CPHA | SPI_CPOL | SPI_CS_HIGH | SPI_LSB_FIRST; + + /* this many pins in all GPIO controllers */ + bbp->master->num_chipselect = num_gpios > 0 ? num_gpios : 0; + + /* Get the clock for the OPB */ + opbnp = of_find_compatible_node(NULL, NULL, "ibm,opb"); + if (opbnp == NULL) { + dev_err(dev, "OPB: cannot find node\n"); + ret = -ENODEV; + goto free_gpios; + } + /* Get the clock (Hz) for the OPB */ + clk = of_get_property(opbnp, "clock-frequency", NULL); + if (clk == NULL) { + dev_err(dev, "OPB: no clock-frequency property set\n"); + of_node_put(opbnp); + ret = -ENODEV; + goto free_gpios; + } + hw->opb_freq = *clk; + hw->opb_freq >>= 2; + of_node_put(opbnp); + + ret = of_address_to_resource(np, 0, &resource); + if (ret) { + dev_err(dev, "error while parsing device node resource\n"); + goto free_gpios; + } + hw->mapbase = resource.start; + hw->mapsize = resource_size(&resource); + + /* Sanity check */ + if (hw->mapsize < sizeof(struct spi_ppc4xx_regs)) { + dev_err(dev, "too small to map registers\n"); + ret = -EINVAL; + goto free_gpios; + } + + /* Request IRQ */ + hw->irqnum = irq_of_parse_and_map(np, 0); + ret = request_irq(hw->irqnum, spi_ppc4xx_int, + 0, "spi_ppc4xx_of", (void *)hw); + if (ret) { + dev_err(dev, "unable to allocate interrupt\n"); + goto free_gpios; + } + + if (!request_mem_region(hw->mapbase, hw->mapsize, DRIVER_NAME)) { + dev_err(dev, "resource unavailable\n"); + ret = -EBUSY; + goto request_mem_error; + } + + hw->regs = ioremap(hw->mapbase, sizeof(struct spi_ppc4xx_regs)); + + if (!hw->regs) { + dev_err(dev, "unable to memory map registers\n"); + ret = -ENXIO; + goto map_io_error; + } + + spi_ppc4xx_enable(hw); + + /* Finally register our spi controller */ + dev->dma_mask = 0; + ret = spi_bitbang_start(bbp); + if (ret) { + dev_err(dev, "failed to register SPI master\n"); + goto unmap_regs; + } + + dev_info(dev, "driver initialized\n"); + + return 0; + +unmap_regs: + iounmap(hw->regs); +map_io_error: + release_mem_region(hw->mapbase, hw->mapsize); +request_mem_error: + free_irq(hw->irqnum, hw); +free_gpios: + free_gpios(hw); +free_master: + spi_master_put(master); + + dev_err(dev, "initialization failed\n"); + return ret; +} + +static int spi_ppc4xx_of_remove(struct platform_device *op) +{ + struct spi_master *master = platform_get_drvdata(op); + struct ppc4xx_spi *hw = spi_master_get_devdata(master); + + spi_bitbang_stop(&hw->bitbang); + release_mem_region(hw->mapbase, hw->mapsize); + free_irq(hw->irqnum, hw); + iounmap(hw->regs); + free_gpios(hw); + spi_master_put(master); + return 0; +} + +static const struct of_device_id spi_ppc4xx_of_match[] = { + { .compatible = "ibm,ppc4xx-spi", }, + {}, +}; + +MODULE_DEVICE_TABLE(of, spi_ppc4xx_of_match); + +static struct platform_driver spi_ppc4xx_of_driver = { + .probe = spi_ppc4xx_of_probe, + .remove = spi_ppc4xx_of_remove, + .driver = { + .name = DRIVER_NAME, + .of_match_table = spi_ppc4xx_of_match, + }, +}; +module_platform_driver(spi_ppc4xx_of_driver); + +MODULE_AUTHOR("Gary Jennejohn & Stefan Roese"); +MODULE_DESCRIPTION("Simple PPC4xx SPI Driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/spi/spi-pxa2xx-dma.c b/drivers/spi/spi-pxa2xx-dma.c new file mode 100644 index 000000000..66a173939 --- /dev/null +++ b/drivers/spi/spi-pxa2xx-dma.c @@ -0,0 +1,368 @@ +/* + * PXA2xx SPI DMA engine support. + * + * Copyright (C) 2013, Intel Corporation + * Author: Mika Westerberg <mika.westerberg@linux.intel.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/device.h> +#include <linux/dma-mapping.h> +#include <linux/dmaengine.h> +#include <linux/pxa2xx_ssp.h> +#include <linux/scatterlist.h> +#include <linux/sizes.h> +#include <linux/spi/spi.h> +#include <linux/spi/pxa2xx_spi.h> + +#include "spi-pxa2xx.h" + +static int pxa2xx_spi_map_dma_buffer(struct driver_data *drv_data, + enum dma_data_direction dir) +{ + int i, nents, len = drv_data->len; + struct scatterlist *sg; + struct device *dmadev; + struct sg_table *sgt; + void *buf, *pbuf; + + if (dir == DMA_TO_DEVICE) { + dmadev = drv_data->tx_chan->device->dev; + sgt = &drv_data->tx_sgt; + buf = drv_data->tx; + drv_data->tx_map_len = len; + } else { + dmadev = drv_data->rx_chan->device->dev; + sgt = &drv_data->rx_sgt; + buf = drv_data->rx; + drv_data->rx_map_len = len; + } + + nents = DIV_ROUND_UP(len, SZ_2K); + if (nents != sgt->nents) { + int ret; + + sg_free_table(sgt); + ret = sg_alloc_table(sgt, nents, GFP_ATOMIC); + if (ret) + return ret; + } + + pbuf = buf; + for_each_sg(sgt->sgl, sg, sgt->nents, i) { + size_t bytes = min_t(size_t, len, SZ_2K); + + if (buf) + sg_set_buf(sg, pbuf, bytes); + else + sg_set_buf(sg, drv_data->dummy, bytes); + + pbuf += bytes; + len -= bytes; + } + + nents = dma_map_sg(dmadev, sgt->sgl, sgt->nents, dir); + if (!nents) + return -ENOMEM; + + return nents; +} + +static void pxa2xx_spi_unmap_dma_buffer(struct driver_data *drv_data, + enum dma_data_direction dir) +{ + struct device *dmadev; + struct sg_table *sgt; + + if (dir == DMA_TO_DEVICE) { + dmadev = drv_data->tx_chan->device->dev; + sgt = &drv_data->tx_sgt; + } else { + dmadev = drv_data->rx_chan->device->dev; + sgt = &drv_data->rx_sgt; + } + + dma_unmap_sg(dmadev, sgt->sgl, sgt->nents, dir); +} + +static void pxa2xx_spi_unmap_dma_buffers(struct driver_data *drv_data) +{ + if (!drv_data->dma_mapped) + return; + + pxa2xx_spi_unmap_dma_buffer(drv_data, DMA_FROM_DEVICE); + pxa2xx_spi_unmap_dma_buffer(drv_data, DMA_TO_DEVICE); + + drv_data->dma_mapped = 0; +} + +static void pxa2xx_spi_dma_transfer_complete(struct driver_data *drv_data, + bool error) +{ + struct spi_message *msg = drv_data->cur_msg; + + /* + * It is possible that one CPU is handling ROR interrupt and other + * just gets DMA completion. Calling pump_transfers() twice for the + * same transfer leads to problems thus we prevent concurrent calls + * by using ->dma_running. + */ + if (atomic_dec_and_test(&drv_data->dma_running)) { + /* + * If the other CPU is still handling the ROR interrupt we + * might not know about the error yet. So we re-check the + * ROR bit here before we clear the status register. + */ + if (!error) { + u32 status = pxa2xx_spi_read(drv_data, SSSR) + & drv_data->mask_sr; + error = status & SSSR_ROR; + } + + /* Clear status & disable interrupts */ + pxa2xx_spi_write(drv_data, SSCR1, + pxa2xx_spi_read(drv_data, SSCR1) + & ~drv_data->dma_cr1); + write_SSSR_CS(drv_data, drv_data->clear_sr); + if (!pxa25x_ssp_comp(drv_data)) + pxa2xx_spi_write(drv_data, SSTO, 0); + + if (!error) { + pxa2xx_spi_unmap_dma_buffers(drv_data); + + drv_data->tx += drv_data->tx_map_len; + drv_data->rx += drv_data->rx_map_len; + + msg->actual_length += drv_data->len; + msg->state = pxa2xx_spi_next_transfer(drv_data); + } else { + /* In case we got an error we disable the SSP now */ + pxa2xx_spi_write(drv_data, SSCR0, + pxa2xx_spi_read(drv_data, SSCR0) + & ~SSCR0_SSE); + + msg->state = ERROR_STATE; + } + + tasklet_schedule(&drv_data->pump_transfers); + } +} + +static void pxa2xx_spi_dma_callback(void *data) +{ + pxa2xx_spi_dma_transfer_complete(data, false); +} + +static struct dma_async_tx_descriptor * +pxa2xx_spi_dma_prepare_one(struct driver_data *drv_data, + enum dma_transfer_direction dir) +{ + struct chip_data *chip = drv_data->cur_chip; + enum dma_slave_buswidth width; + struct dma_slave_config cfg; + struct dma_chan *chan; + struct sg_table *sgt; + int nents, ret; + + switch (drv_data->n_bytes) { + case 1: + width = DMA_SLAVE_BUSWIDTH_1_BYTE; + break; + case 2: + width = DMA_SLAVE_BUSWIDTH_2_BYTES; + break; + default: + width = DMA_SLAVE_BUSWIDTH_4_BYTES; + break; + } + + memset(&cfg, 0, sizeof(cfg)); + cfg.direction = dir; + + if (dir == DMA_MEM_TO_DEV) { + cfg.dst_addr = drv_data->ssdr_physical; + cfg.dst_addr_width = width; + cfg.dst_maxburst = chip->dma_burst_size; + + sgt = &drv_data->tx_sgt; + nents = drv_data->tx_nents; + chan = drv_data->tx_chan; + } else { + cfg.src_addr = drv_data->ssdr_physical; + cfg.src_addr_width = width; + cfg.src_maxburst = chip->dma_burst_size; + + sgt = &drv_data->rx_sgt; + nents = drv_data->rx_nents; + chan = drv_data->rx_chan; + } + + ret = dmaengine_slave_config(chan, &cfg); + if (ret) { + dev_warn(&drv_data->pdev->dev, "DMA slave config failed\n"); + return NULL; + } + + return dmaengine_prep_slave_sg(chan, sgt->sgl, nents, dir, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); +} + +bool pxa2xx_spi_dma_is_possible(size_t len) +{ + return len <= MAX_DMA_LEN; +} + +int pxa2xx_spi_map_dma_buffers(struct driver_data *drv_data) +{ + const struct chip_data *chip = drv_data->cur_chip; + int ret; + + if (!chip->enable_dma) + return 0; + + /* Don't bother with DMA if we can't do even a single burst */ + if (drv_data->len < chip->dma_burst_size) + return 0; + + ret = pxa2xx_spi_map_dma_buffer(drv_data, DMA_TO_DEVICE); + if (ret <= 0) { + dev_warn(&drv_data->pdev->dev, "failed to DMA map TX\n"); + return 0; + } + + drv_data->tx_nents = ret; + + ret = pxa2xx_spi_map_dma_buffer(drv_data, DMA_FROM_DEVICE); + if (ret <= 0) { + pxa2xx_spi_unmap_dma_buffer(drv_data, DMA_TO_DEVICE); + dev_warn(&drv_data->pdev->dev, "failed to DMA map RX\n"); + return 0; + } + + drv_data->rx_nents = ret; + return 1; +} + +irqreturn_t pxa2xx_spi_dma_transfer(struct driver_data *drv_data) +{ + u32 status; + + status = pxa2xx_spi_read(drv_data, SSSR) & drv_data->mask_sr; + if (status & SSSR_ROR) { + dev_err(&drv_data->pdev->dev, "FIFO overrun\n"); + + dmaengine_terminate_all(drv_data->rx_chan); + dmaengine_terminate_all(drv_data->tx_chan); + + pxa2xx_spi_dma_transfer_complete(drv_data, true); + return IRQ_HANDLED; + } + + return IRQ_NONE; +} + +int pxa2xx_spi_dma_prepare(struct driver_data *drv_data, u32 dma_burst) +{ + struct dma_async_tx_descriptor *tx_desc, *rx_desc; + + tx_desc = pxa2xx_spi_dma_prepare_one(drv_data, DMA_MEM_TO_DEV); + if (!tx_desc) { + dev_err(&drv_data->pdev->dev, + "failed to get DMA TX descriptor\n"); + return -EBUSY; + } + + rx_desc = pxa2xx_spi_dma_prepare_one(drv_data, DMA_DEV_TO_MEM); + if (!rx_desc) { + dev_err(&drv_data->pdev->dev, + "failed to get DMA RX descriptor\n"); + return -EBUSY; + } + + /* We are ready when RX completes */ + rx_desc->callback = pxa2xx_spi_dma_callback; + rx_desc->callback_param = drv_data; + + dmaengine_submit(rx_desc); + dmaengine_submit(tx_desc); + return 0; +} + +void pxa2xx_spi_dma_start(struct driver_data *drv_data) +{ + dma_async_issue_pending(drv_data->rx_chan); + dma_async_issue_pending(drv_data->tx_chan); + + atomic_set(&drv_data->dma_running, 1); +} + +int pxa2xx_spi_dma_setup(struct driver_data *drv_data) +{ + struct pxa2xx_spi_master *pdata = drv_data->master_info; + struct device *dev = &drv_data->pdev->dev; + dma_cap_mask_t mask; + + dma_cap_zero(mask); + dma_cap_set(DMA_SLAVE, mask); + + drv_data->dummy = devm_kzalloc(dev, SZ_2K, GFP_KERNEL); + if (!drv_data->dummy) + return -ENOMEM; + + drv_data->tx_chan = dma_request_slave_channel_compat(mask, + pdata->dma_filter, pdata->tx_param, dev, "tx"); + if (!drv_data->tx_chan) + return -ENODEV; + + drv_data->rx_chan = dma_request_slave_channel_compat(mask, + pdata->dma_filter, pdata->rx_param, dev, "rx"); + if (!drv_data->rx_chan) { + dma_release_channel(drv_data->tx_chan); + drv_data->tx_chan = NULL; + return -ENODEV; + } + + return 0; +} + +void pxa2xx_spi_dma_release(struct driver_data *drv_data) +{ + if (drv_data->rx_chan) { + dmaengine_terminate_all(drv_data->rx_chan); + dma_release_channel(drv_data->rx_chan); + sg_free_table(&drv_data->rx_sgt); + drv_data->rx_chan = NULL; + } + if (drv_data->tx_chan) { + dmaengine_terminate_all(drv_data->tx_chan); + dma_release_channel(drv_data->tx_chan); + sg_free_table(&drv_data->tx_sgt); + drv_data->tx_chan = NULL; + } +} + +void pxa2xx_spi_dma_resume(struct driver_data *drv_data) +{ +} + +int pxa2xx_spi_set_dma_burst_and_threshold(struct chip_data *chip, + struct spi_device *spi, + u8 bits_per_word, u32 *burst_code, + u32 *threshold) +{ + struct pxa2xx_spi_chip *chip_info = spi->controller_data; + + /* + * If the DMA burst size is given in chip_info we use that, + * otherwise we use the default. Also we use the default FIFO + * thresholds for now. + */ + *burst_code = chip_info ? chip_info->dma_burst_size : 1; + *threshold = SSCR1_RxTresh(RX_THRESH_DFLT) + | SSCR1_TxTresh(TX_THRESH_DFLT); + + return 0; +} diff --git a/drivers/spi/spi-pxa2xx-pci.c b/drivers/spi/spi-pxa2xx-pci.c new file mode 100644 index 000000000..fa7399e84 --- /dev/null +++ b/drivers/spi/spi-pxa2xx-pci.c @@ -0,0 +1,221 @@ +/* + * CE4100's SPI device is more or less the same one as found on PXA + * + */ +#include <linux/pci.h> +#include <linux/platform_device.h> +#include <linux/of_device.h> +#include <linux/module.h> +#include <linux/spi/pxa2xx_spi.h> +#include <linux/clk.h> +#include <linux/clk-provider.h> + +#include <linux/dmaengine.h> +#include <linux/platform_data/dma-dw.h> + +enum { + PORT_CE4100, + PORT_BYT, + PORT_BSW0, + PORT_BSW1, + PORT_BSW2, + PORT_QUARK_X1000, +}; + +struct pxa_spi_info { + enum pxa_ssp_type type; + int port_id; + int num_chipselect; + unsigned long max_clk_rate; + + /* DMA channel request parameters */ + void *tx_param; + void *rx_param; +}; + +static struct dw_dma_slave byt_tx_param = { .dst_id = 0 }; +static struct dw_dma_slave byt_rx_param = { .src_id = 1 }; + +static struct dw_dma_slave bsw0_tx_param = { .dst_id = 0 }; +static struct dw_dma_slave bsw0_rx_param = { .src_id = 1 }; +static struct dw_dma_slave bsw1_tx_param = { .dst_id = 6 }; +static struct dw_dma_slave bsw1_rx_param = { .src_id = 7 }; +static struct dw_dma_slave bsw2_tx_param = { .dst_id = 8 }; +static struct dw_dma_slave bsw2_rx_param = { .src_id = 9 }; + +static bool lpss_dma_filter(struct dma_chan *chan, void *param) +{ + struct dw_dma_slave *dws = param; + + if (dws->dma_dev != chan->device->dev) + return false; + + chan->private = dws; + return true; +} + +static struct pxa_spi_info spi_info_configs[] = { + [PORT_CE4100] = { + .type = PXA25x_SSP, + .port_id = -1, + .num_chipselect = -1, + .max_clk_rate = 3686400, + }, + [PORT_BYT] = { + .type = LPSS_SSP, + .port_id = 0, + .num_chipselect = 1, + .max_clk_rate = 50000000, + .tx_param = &byt_tx_param, + .rx_param = &byt_rx_param, + }, + [PORT_BSW0] = { + .type = LPSS_SSP, + .port_id = 0, + .num_chipselect = 1, + .max_clk_rate = 50000000, + .tx_param = &bsw0_tx_param, + .rx_param = &bsw0_rx_param, + }, + [PORT_BSW1] = { + .type = LPSS_SSP, + .port_id = 1, + .num_chipselect = 1, + .max_clk_rate = 50000000, + .tx_param = &bsw1_tx_param, + .rx_param = &bsw1_rx_param, + }, + [PORT_BSW2] = { + .type = LPSS_SSP, + .port_id = 2, + .num_chipselect = 1, + .max_clk_rate = 50000000, + .tx_param = &bsw2_tx_param, + .rx_param = &bsw2_rx_param, + }, + [PORT_QUARK_X1000] = { + .type = QUARK_X1000_SSP, + .port_id = -1, + .num_chipselect = 1, + .max_clk_rate = 50000000, + }, +}; + +static int pxa2xx_spi_pci_probe(struct pci_dev *dev, + const struct pci_device_id *ent) +{ + struct platform_device_info pi; + int ret; + struct platform_device *pdev; + struct pxa2xx_spi_master spi_pdata; + struct ssp_device *ssp; + struct pxa_spi_info *c; + char buf[40]; + struct pci_dev *dma_dev; + + ret = pcim_enable_device(dev); + if (ret) + return ret; + + ret = pcim_iomap_regions(dev, 1 << 0, "PXA2xx SPI"); + if (ret) + return ret; + + c = &spi_info_configs[ent->driver_data]; + + memset(&spi_pdata, 0, sizeof(spi_pdata)); + spi_pdata.num_chipselect = (c->num_chipselect > 0) ? + c->num_chipselect : dev->devfn; + + dma_dev = pci_get_slot(dev->bus, PCI_DEVFN(PCI_SLOT(dev->devfn), 0)); + + if (c->tx_param) { + struct dw_dma_slave *slave = c->tx_param; + + slave->dma_dev = &dma_dev->dev; + slave->src_master = 1; + slave->dst_master = 0; + } + + if (c->rx_param) { + struct dw_dma_slave *slave = c->rx_param; + + slave->dma_dev = &dma_dev->dev; + slave->src_master = 1; + slave->dst_master = 0; + } + + spi_pdata.dma_filter = lpss_dma_filter; + spi_pdata.tx_param = c->tx_param; + spi_pdata.rx_param = c->rx_param; + spi_pdata.enable_dma = c->rx_param && c->tx_param; + + ssp = &spi_pdata.ssp; + ssp->phys_base = pci_resource_start(dev, 0); + ssp->mmio_base = pcim_iomap_table(dev)[0]; + if (!ssp->mmio_base) { + dev_err(&dev->dev, "failed to ioremap() registers\n"); + return -EIO; + } + ssp->irq = dev->irq; + ssp->port_id = (c->port_id >= 0) ? c->port_id : dev->devfn; + ssp->type = c->type; + + snprintf(buf, sizeof(buf), "pxa2xx-spi.%d", ssp->port_id); + ssp->clk = clk_register_fixed_rate(&dev->dev, buf , NULL, + CLK_IS_ROOT, c->max_clk_rate); + if (IS_ERR(ssp->clk)) + return PTR_ERR(ssp->clk); + + memset(&pi, 0, sizeof(pi)); + pi.parent = &dev->dev; + pi.name = "pxa2xx-spi"; + pi.id = ssp->port_id; + pi.data = &spi_pdata; + pi.size_data = sizeof(spi_pdata); + + pdev = platform_device_register_full(&pi); + if (IS_ERR(pdev)) { + clk_unregister(ssp->clk); + return PTR_ERR(pdev); + } + + pci_set_drvdata(dev, pdev); + + return 0; +} + +static void pxa2xx_spi_pci_remove(struct pci_dev *dev) +{ + struct platform_device *pdev = pci_get_drvdata(dev); + struct pxa2xx_spi_master *spi_pdata; + + spi_pdata = dev_get_platdata(&pdev->dev); + + platform_device_unregister(pdev); + clk_unregister(spi_pdata->ssp.clk); +} + +static const struct pci_device_id pxa2xx_spi_pci_devices[] = { + { PCI_VDEVICE(INTEL, 0x2e6a), PORT_CE4100 }, + { PCI_VDEVICE(INTEL, 0x0935), PORT_QUARK_X1000 }, + { PCI_VDEVICE(INTEL, 0x0f0e), PORT_BYT }, + { PCI_VDEVICE(INTEL, 0x228e), PORT_BSW0 }, + { PCI_VDEVICE(INTEL, 0x2290), PORT_BSW1 }, + { PCI_VDEVICE(INTEL, 0x22ac), PORT_BSW2 }, + { }, +}; +MODULE_DEVICE_TABLE(pci, pxa2xx_spi_pci_devices); + +static struct pci_driver pxa2xx_spi_pci_driver = { + .name = "pxa2xx_spi_pci", + .id_table = pxa2xx_spi_pci_devices, + .probe = pxa2xx_spi_pci_probe, + .remove = pxa2xx_spi_pci_remove, +}; + +module_pci_driver(pxa2xx_spi_pci_driver); + +MODULE_DESCRIPTION("CE4100/LPSS PCI-SPI glue code for PXA's driver"); +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR("Sebastian Andrzej Siewior <bigeasy@linutronix.de>"); diff --git a/drivers/spi/spi-pxa2xx-pxadma.c b/drivers/spi/spi-pxa2xx-pxadma.c new file mode 100644 index 000000000..2e0796a00 --- /dev/null +++ b/drivers/spi/spi-pxa2xx-pxadma.c @@ -0,0 +1,487 @@ +/* + * PXA2xx SPI private DMA support. + * + * Copyright (C) 2005 Stephen Street / StreetFire Sound Labs + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/dma-mapping.h> +#include <linux/pxa2xx_ssp.h> +#include <linux/spi/spi.h> +#include <linux/spi/pxa2xx_spi.h> + +#include <mach/dma.h> +#include "spi-pxa2xx.h" + +#define DMA_INT_MASK (DCSR_ENDINTR | DCSR_STARTINTR | DCSR_BUSERR) +#define RESET_DMA_CHANNEL (DCSR_NODESC | DMA_INT_MASK) + +bool pxa2xx_spi_dma_is_possible(size_t len) +{ + /* Try to map dma buffer and do a dma transfer if successful, but + * only if the length is non-zero and less than MAX_DMA_LEN. + * + * Zero-length non-descriptor DMA is illegal on PXA2xx; force use + * of PIO instead. Care is needed above because the transfer may + * have have been passed with buffers that are already dma mapped. + * A zero-length transfer in PIO mode will not try to write/read + * to/from the buffers + * + * REVISIT large transfers are exactly where we most want to be + * using DMA. If this happens much, split those transfers into + * multiple DMA segments rather than forcing PIO. + */ + return len > 0 && len <= MAX_DMA_LEN; +} + +int pxa2xx_spi_map_dma_buffers(struct driver_data *drv_data) +{ + struct spi_message *msg = drv_data->cur_msg; + struct device *dev = &msg->spi->dev; + + if (!drv_data->cur_chip->enable_dma) + return 0; + + if (msg->is_dma_mapped) + return drv_data->rx_dma && drv_data->tx_dma; + + if (!IS_DMA_ALIGNED(drv_data->rx) || !IS_DMA_ALIGNED(drv_data->tx)) + return 0; + + /* Modify setup if rx buffer is null */ + if (drv_data->rx == NULL) { + *drv_data->null_dma_buf = 0; + drv_data->rx = drv_data->null_dma_buf; + drv_data->rx_map_len = 4; + } else + drv_data->rx_map_len = drv_data->len; + + + /* Modify setup if tx buffer is null */ + if (drv_data->tx == NULL) { + *drv_data->null_dma_buf = 0; + drv_data->tx = drv_data->null_dma_buf; + drv_data->tx_map_len = 4; + } else + drv_data->tx_map_len = drv_data->len; + + /* Stream map the tx buffer. Always do DMA_TO_DEVICE first + * so we flush the cache *before* invalidating it, in case + * the tx and rx buffers overlap. + */ + drv_data->tx_dma = dma_map_single(dev, drv_data->tx, + drv_data->tx_map_len, DMA_TO_DEVICE); + if (dma_mapping_error(dev, drv_data->tx_dma)) + return 0; + + /* Stream map the rx buffer */ + drv_data->rx_dma = dma_map_single(dev, drv_data->rx, + drv_data->rx_map_len, DMA_FROM_DEVICE); + if (dma_mapping_error(dev, drv_data->rx_dma)) { + dma_unmap_single(dev, drv_data->tx_dma, + drv_data->tx_map_len, DMA_TO_DEVICE); + return 0; + } + + return 1; +} + +static void pxa2xx_spi_unmap_dma_buffers(struct driver_data *drv_data) +{ + struct device *dev; + + if (!drv_data->dma_mapped) + return; + + if (!drv_data->cur_msg->is_dma_mapped) { + dev = &drv_data->cur_msg->spi->dev; + dma_unmap_single(dev, drv_data->rx_dma, + drv_data->rx_map_len, DMA_FROM_DEVICE); + dma_unmap_single(dev, drv_data->tx_dma, + drv_data->tx_map_len, DMA_TO_DEVICE); + } + + drv_data->dma_mapped = 0; +} + +static int wait_ssp_rx_stall(struct driver_data *drv_data) +{ + unsigned long limit = loops_per_jiffy << 1; + + while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_BSY) && --limit) + cpu_relax(); + + return limit; +} + +static int wait_dma_channel_stop(int channel) +{ + unsigned long limit = loops_per_jiffy << 1; + + while (!(DCSR(channel) & DCSR_STOPSTATE) && --limit) + cpu_relax(); + + return limit; +} + +static void pxa2xx_spi_dma_error_stop(struct driver_data *drv_data, + const char *msg) +{ + /* Stop and reset */ + DCSR(drv_data->rx_channel) = RESET_DMA_CHANNEL; + DCSR(drv_data->tx_channel) = RESET_DMA_CHANNEL; + write_SSSR_CS(drv_data, drv_data->clear_sr); + pxa2xx_spi_write(drv_data, SSCR1, + pxa2xx_spi_read(drv_data, SSCR1) + & ~drv_data->dma_cr1); + if (!pxa25x_ssp_comp(drv_data)) + pxa2xx_spi_write(drv_data, SSTO, 0); + pxa2xx_spi_flush(drv_data); + pxa2xx_spi_write(drv_data, SSCR0, + pxa2xx_spi_read(drv_data, SSCR0) & ~SSCR0_SSE); + + pxa2xx_spi_unmap_dma_buffers(drv_data); + + dev_err(&drv_data->pdev->dev, "%s\n", msg); + + drv_data->cur_msg->state = ERROR_STATE; + tasklet_schedule(&drv_data->pump_transfers); +} + +static void pxa2xx_spi_dma_transfer_complete(struct driver_data *drv_data) +{ + struct spi_message *msg = drv_data->cur_msg; + + /* Clear and disable interrupts on SSP and DMA channels*/ + pxa2xx_spi_write(drv_data, SSCR1, + pxa2xx_spi_read(drv_data, SSCR1) + & ~drv_data->dma_cr1); + write_SSSR_CS(drv_data, drv_data->clear_sr); + DCSR(drv_data->tx_channel) = RESET_DMA_CHANNEL; + DCSR(drv_data->rx_channel) = RESET_DMA_CHANNEL; + + if (wait_dma_channel_stop(drv_data->rx_channel) == 0) + dev_err(&drv_data->pdev->dev, + "dma_handler: dma rx channel stop failed\n"); + + if (wait_ssp_rx_stall(drv_data->ioaddr) == 0) + dev_err(&drv_data->pdev->dev, + "dma_transfer: ssp rx stall failed\n"); + + pxa2xx_spi_unmap_dma_buffers(drv_data); + + /* update the buffer pointer for the amount completed in dma */ + drv_data->rx += drv_data->len - + (DCMD(drv_data->rx_channel) & DCMD_LENGTH); + + /* read trailing data from fifo, it does not matter how many + * bytes are in the fifo just read until buffer is full + * or fifo is empty, which ever occurs first */ + drv_data->read(drv_data); + + /* return count of what was actually read */ + msg->actual_length += drv_data->len - + (drv_data->rx_end - drv_data->rx); + + /* Transfer delays and chip select release are + * handled in pump_transfers or giveback + */ + + /* Move to next transfer */ + msg->state = pxa2xx_spi_next_transfer(drv_data); + + /* Schedule transfer tasklet */ + tasklet_schedule(&drv_data->pump_transfers); +} + +void pxa2xx_spi_dma_handler(int channel, void *data) +{ + struct driver_data *drv_data = data; + u32 irq_status = DCSR(channel) & DMA_INT_MASK; + + if (irq_status & DCSR_BUSERR) { + + if (channel == drv_data->tx_channel) + pxa2xx_spi_dma_error_stop(drv_data, + "dma_handler: bad bus address on tx channel"); + else + pxa2xx_spi_dma_error_stop(drv_data, + "dma_handler: bad bus address on rx channel"); + return; + } + + /* PXA255x_SSP has no timeout interrupt, wait for tailing bytes */ + if ((channel == drv_data->tx_channel) + && (irq_status & DCSR_ENDINTR) + && (drv_data->ssp_type == PXA25x_SSP)) { + + /* Wait for rx to stall */ + if (wait_ssp_rx_stall(drv_data) == 0) + dev_err(&drv_data->pdev->dev, + "dma_handler: ssp rx stall failed\n"); + + /* finish this transfer, start the next */ + pxa2xx_spi_dma_transfer_complete(drv_data); + } +} + +irqreturn_t pxa2xx_spi_dma_transfer(struct driver_data *drv_data) +{ + u32 irq_status; + + irq_status = pxa2xx_spi_read(drv_data, SSSR) & drv_data->mask_sr; + if (irq_status & SSSR_ROR) { + pxa2xx_spi_dma_error_stop(drv_data, + "dma_transfer: fifo overrun"); + return IRQ_HANDLED; + } + + /* Check for false positive timeout */ + if ((irq_status & SSSR_TINT) + && (DCSR(drv_data->tx_channel) & DCSR_RUN)) { + pxa2xx_spi_write(drv_data, SSSR, SSSR_TINT); + return IRQ_HANDLED; + } + + if (irq_status & SSSR_TINT || drv_data->rx == drv_data->rx_end) { + + /* Clear and disable timeout interrupt, do the rest in + * dma_transfer_complete */ + if (!pxa25x_ssp_comp(drv_data)) + pxa2xx_spi_write(drv_data, SSTO, 0); + + /* finish this transfer, start the next */ + pxa2xx_spi_dma_transfer_complete(drv_data); + + return IRQ_HANDLED; + } + + /* Opps problem detected */ + return IRQ_NONE; +} + +int pxa2xx_spi_dma_prepare(struct driver_data *drv_data, u32 dma_burst) +{ + u32 dma_width; + + switch (drv_data->n_bytes) { + case 1: + dma_width = DCMD_WIDTH1; + break; + case 2: + dma_width = DCMD_WIDTH2; + break; + default: + dma_width = DCMD_WIDTH4; + break; + } + + /* Setup rx DMA Channel */ + DCSR(drv_data->rx_channel) = RESET_DMA_CHANNEL; + DSADR(drv_data->rx_channel) = drv_data->ssdr_physical; + DTADR(drv_data->rx_channel) = drv_data->rx_dma; + if (drv_data->rx == drv_data->null_dma_buf) + /* No target address increment */ + DCMD(drv_data->rx_channel) = DCMD_FLOWSRC + | dma_width + | dma_burst + | drv_data->len; + else + DCMD(drv_data->rx_channel) = DCMD_INCTRGADDR + | DCMD_FLOWSRC + | dma_width + | dma_burst + | drv_data->len; + + /* Setup tx DMA Channel */ + DCSR(drv_data->tx_channel) = RESET_DMA_CHANNEL; + DSADR(drv_data->tx_channel) = drv_data->tx_dma; + DTADR(drv_data->tx_channel) = drv_data->ssdr_physical; + if (drv_data->tx == drv_data->null_dma_buf) + /* No source address increment */ + DCMD(drv_data->tx_channel) = DCMD_FLOWTRG + | dma_width + | dma_burst + | drv_data->len; + else + DCMD(drv_data->tx_channel) = DCMD_INCSRCADDR + | DCMD_FLOWTRG + | dma_width + | dma_burst + | drv_data->len; + + /* Enable dma end irqs on SSP to detect end of transfer */ + if (drv_data->ssp_type == PXA25x_SSP) + DCMD(drv_data->tx_channel) |= DCMD_ENDIRQEN; + + return 0; +} + +void pxa2xx_spi_dma_start(struct driver_data *drv_data) +{ + DCSR(drv_data->rx_channel) |= DCSR_RUN; + DCSR(drv_data->tx_channel) |= DCSR_RUN; +} + +int pxa2xx_spi_dma_setup(struct driver_data *drv_data) +{ + struct device *dev = &drv_data->pdev->dev; + struct ssp_device *ssp = drv_data->ssp; + + /* Get two DMA channels (rx and tx) */ + drv_data->rx_channel = pxa_request_dma("pxa2xx_spi_ssp_rx", + DMA_PRIO_HIGH, + pxa2xx_spi_dma_handler, + drv_data); + if (drv_data->rx_channel < 0) { + dev_err(dev, "problem (%d) requesting rx channel\n", + drv_data->rx_channel); + return -ENODEV; + } + drv_data->tx_channel = pxa_request_dma("pxa2xx_spi_ssp_tx", + DMA_PRIO_MEDIUM, + pxa2xx_spi_dma_handler, + drv_data); + if (drv_data->tx_channel < 0) { + dev_err(dev, "problem (%d) requesting tx channel\n", + drv_data->tx_channel); + pxa_free_dma(drv_data->rx_channel); + return -ENODEV; + } + + DRCMR(ssp->drcmr_rx) = DRCMR_MAPVLD | drv_data->rx_channel; + DRCMR(ssp->drcmr_tx) = DRCMR_MAPVLD | drv_data->tx_channel; + + return 0; +} + +void pxa2xx_spi_dma_release(struct driver_data *drv_data) +{ + struct ssp_device *ssp = drv_data->ssp; + + DRCMR(ssp->drcmr_rx) = 0; + DRCMR(ssp->drcmr_tx) = 0; + + if (drv_data->tx_channel != 0) + pxa_free_dma(drv_data->tx_channel); + if (drv_data->rx_channel != 0) + pxa_free_dma(drv_data->rx_channel); +} + +void pxa2xx_spi_dma_resume(struct driver_data *drv_data) +{ + if (drv_data->rx_channel != -1) + DRCMR(drv_data->ssp->drcmr_rx) = + DRCMR_MAPVLD | drv_data->rx_channel; + if (drv_data->tx_channel != -1) + DRCMR(drv_data->ssp->drcmr_tx) = + DRCMR_MAPVLD | drv_data->tx_channel; +} + +int pxa2xx_spi_set_dma_burst_and_threshold(struct chip_data *chip, + struct spi_device *spi, + u8 bits_per_word, u32 *burst_code, + u32 *threshold) +{ + struct pxa2xx_spi_chip *chip_info = + (struct pxa2xx_spi_chip *)spi->controller_data; + int bytes_per_word; + int burst_bytes; + int thresh_words; + int req_burst_size; + int retval = 0; + + /* Set the threshold (in registers) to equal the same amount of data + * as represented by burst size (in bytes). The computation below + * is (burst_size rounded up to nearest 8 byte, word or long word) + * divided by (bytes/register); the tx threshold is the inverse of + * the rx, so that there will always be enough data in the rx fifo + * to satisfy a burst, and there will always be enough space in the + * tx fifo to accept a burst (a tx burst will overwrite the fifo if + * there is not enough space), there must always remain enough empty + * space in the rx fifo for any data loaded to the tx fifo. + * Whenever burst_size (in bytes) equals bits/word, the fifo threshold + * will be 8, or half the fifo; + * The threshold can only be set to 2, 4 or 8, but not 16, because + * to burst 16 to the tx fifo, the fifo would have to be empty; + * however, the minimum fifo trigger level is 1, and the tx will + * request service when the fifo is at this level, with only 15 spaces. + */ + + /* find bytes/word */ + if (bits_per_word <= 8) + bytes_per_word = 1; + else if (bits_per_word <= 16) + bytes_per_word = 2; + else + bytes_per_word = 4; + + /* use struct pxa2xx_spi_chip->dma_burst_size if available */ + if (chip_info) + req_burst_size = chip_info->dma_burst_size; + else { + switch (chip->dma_burst_size) { + default: + /* if the default burst size is not set, + * do it now */ + chip->dma_burst_size = DCMD_BURST8; + case DCMD_BURST8: + req_burst_size = 8; + break; + case DCMD_BURST16: + req_burst_size = 16; + break; + case DCMD_BURST32: + req_burst_size = 32; + break; + } + } + if (req_burst_size <= 8) { + *burst_code = DCMD_BURST8; + burst_bytes = 8; + } else if (req_burst_size <= 16) { + if (bytes_per_word == 1) { + /* don't burst more than 1/2 the fifo */ + *burst_code = DCMD_BURST8; + burst_bytes = 8; + retval = 1; + } else { + *burst_code = DCMD_BURST16; + burst_bytes = 16; + } + } else { + if (bytes_per_word == 1) { + /* don't burst more than 1/2 the fifo */ + *burst_code = DCMD_BURST8; + burst_bytes = 8; + retval = 1; + } else if (bytes_per_word == 2) { + /* don't burst more than 1/2 the fifo */ + *burst_code = DCMD_BURST16; + burst_bytes = 16; + retval = 1; + } else { + *burst_code = DCMD_BURST32; + burst_bytes = 32; + } + } + + thresh_words = burst_bytes / bytes_per_word; + + /* thresh_words will be between 2 and 8 */ + *threshold = (SSCR1_RxTresh(thresh_words) & SSCR1_RFT) + | (SSCR1_TxTresh(16-thresh_words) & SSCR1_TFT); + + return retval; +} diff --git a/drivers/spi/spi-pxa2xx.c b/drivers/spi/spi-pxa2xx.c new file mode 100644 index 000000000..e3223ac75 --- /dev/null +++ b/drivers/spi/spi-pxa2xx.c @@ -0,0 +1,1600 @@ +/* + * Copyright (C) 2005 Stephen Street / StreetFire Sound Labs + * Copyright (C) 2013, Intel Corporation + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/init.h> +#include <linux/module.h> +#include <linux/device.h> +#include <linux/ioport.h> +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/interrupt.h> +#include <linux/kernel.h> +#include <linux/platform_device.h> +#include <linux/spi/pxa2xx_spi.h> +#include <linux/spi/spi.h> +#include <linux/delay.h> +#include <linux/gpio.h> +#include <linux/slab.h> +#include <linux/clk.h> +#include <linux/pm_runtime.h> +#include <linux/acpi.h> + +#include "spi-pxa2xx.h" + +MODULE_AUTHOR("Stephen Street"); +MODULE_DESCRIPTION("PXA2xx SSP SPI Controller"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:pxa2xx-spi"); + +#define TIMOUT_DFLT 1000 + +/* + * for testing SSCR1 changes that require SSP restart, basically + * everything except the service and interrupt enables, the pxa270 developer + * manual says only SSCR1_SCFR, SSCR1_SPH, SSCR1_SPO need to be in this + * list, but the PXA255 dev man says all bits without really meaning the + * service and interrupt enables + */ +#define SSCR1_CHANGE_MASK (SSCR1_TTELP | SSCR1_TTE | SSCR1_SCFR \ + | SSCR1_ECRA | SSCR1_ECRB | SSCR1_SCLKDIR \ + | SSCR1_SFRMDIR | SSCR1_RWOT | SSCR1_TRAIL \ + | SSCR1_IFS | SSCR1_STRF | SSCR1_EFWR \ + | SSCR1_RFT | SSCR1_TFT | SSCR1_MWDS \ + | SSCR1_SPH | SSCR1_SPO | SSCR1_LBM) + +#define QUARK_X1000_SSCR1_CHANGE_MASK (QUARK_X1000_SSCR1_STRF \ + | QUARK_X1000_SSCR1_EFWR \ + | QUARK_X1000_SSCR1_RFT \ + | QUARK_X1000_SSCR1_TFT \ + | SSCR1_SPH | SSCR1_SPO | SSCR1_LBM) + +#define LPSS_RX_THRESH_DFLT 64 +#define LPSS_TX_LOTHRESH_DFLT 160 +#define LPSS_TX_HITHRESH_DFLT 224 + +/* Offset from drv_data->lpss_base */ +#define GENERAL_REG 0x08 +#define GENERAL_REG_RXTO_HOLDOFF_DISABLE BIT(24) +#define SSP_REG 0x0c +#define SPI_CS_CONTROL 0x18 +#define SPI_CS_CONTROL_SW_MODE BIT(0) +#define SPI_CS_CONTROL_CS_HIGH BIT(1) + +static bool is_lpss_ssp(const struct driver_data *drv_data) +{ + return drv_data->ssp_type == LPSS_SSP; +} + +static bool is_quark_x1000_ssp(const struct driver_data *drv_data) +{ + return drv_data->ssp_type == QUARK_X1000_SSP; +} + +static u32 pxa2xx_spi_get_ssrc1_change_mask(const struct driver_data *drv_data) +{ + switch (drv_data->ssp_type) { + case QUARK_X1000_SSP: + return QUARK_X1000_SSCR1_CHANGE_MASK; + default: + return SSCR1_CHANGE_MASK; + } +} + +static u32 +pxa2xx_spi_get_rx_default_thre(const struct driver_data *drv_data) +{ + switch (drv_data->ssp_type) { + case QUARK_X1000_SSP: + return RX_THRESH_QUARK_X1000_DFLT; + default: + return RX_THRESH_DFLT; + } +} + +static bool pxa2xx_spi_txfifo_full(const struct driver_data *drv_data) +{ + u32 mask; + + switch (drv_data->ssp_type) { + case QUARK_X1000_SSP: + mask = QUARK_X1000_SSSR_TFL_MASK; + break; + default: + mask = SSSR_TFL_MASK; + break; + } + + return (pxa2xx_spi_read(drv_data, SSSR) & mask) == mask; +} + +static void pxa2xx_spi_clear_rx_thre(const struct driver_data *drv_data, + u32 *sccr1_reg) +{ + u32 mask; + + switch (drv_data->ssp_type) { + case QUARK_X1000_SSP: + mask = QUARK_X1000_SSCR1_RFT; + break; + default: + mask = SSCR1_RFT; + break; + } + *sccr1_reg &= ~mask; +} + +static void pxa2xx_spi_set_rx_thre(const struct driver_data *drv_data, + u32 *sccr1_reg, u32 threshold) +{ + switch (drv_data->ssp_type) { + case QUARK_X1000_SSP: + *sccr1_reg |= QUARK_X1000_SSCR1_RxTresh(threshold); + break; + default: + *sccr1_reg |= SSCR1_RxTresh(threshold); + break; + } +} + +static u32 pxa2xx_configure_sscr0(const struct driver_data *drv_data, + u32 clk_div, u8 bits) +{ + switch (drv_data->ssp_type) { + case QUARK_X1000_SSP: + return clk_div + | QUARK_X1000_SSCR0_Motorola + | QUARK_X1000_SSCR0_DataSize(bits > 32 ? 8 : bits) + | SSCR0_SSE; + default: + return clk_div + | SSCR0_Motorola + | SSCR0_DataSize(bits > 16 ? bits - 16 : bits) + | SSCR0_SSE + | (bits > 16 ? SSCR0_EDSS : 0); + } +} + +/* + * Read and write LPSS SSP private registers. Caller must first check that + * is_lpss_ssp() returns true before these can be called. + */ +static u32 __lpss_ssp_read_priv(struct driver_data *drv_data, unsigned offset) +{ + WARN_ON(!drv_data->lpss_base); + return readl(drv_data->lpss_base + offset); +} + +static void __lpss_ssp_write_priv(struct driver_data *drv_data, + unsigned offset, u32 value) +{ + WARN_ON(!drv_data->lpss_base); + writel(value, drv_data->lpss_base + offset); +} + +/* + * lpss_ssp_setup - perform LPSS SSP specific setup + * @drv_data: pointer to the driver private data + * + * Perform LPSS SSP specific setup. This function must be called first if + * one is going to use LPSS SSP private registers. + */ +static void lpss_ssp_setup(struct driver_data *drv_data) +{ + unsigned offset = 0x400; + u32 value, orig; + + /* + * Perform auto-detection of the LPSS SSP private registers. They + * can be either at 1k or 2k offset from the base address. + */ + orig = readl(drv_data->ioaddr + offset + SPI_CS_CONTROL); + + /* Test SPI_CS_CONTROL_SW_MODE bit enabling */ + value = orig | SPI_CS_CONTROL_SW_MODE; + writel(value, drv_data->ioaddr + offset + SPI_CS_CONTROL); + value = readl(drv_data->ioaddr + offset + SPI_CS_CONTROL); + if (value != (orig | SPI_CS_CONTROL_SW_MODE)) { + offset = 0x800; + goto detection_done; + } + + orig = readl(drv_data->ioaddr + offset + SPI_CS_CONTROL); + + /* Test SPI_CS_CONTROL_SW_MODE bit disabling */ + value = orig & ~SPI_CS_CONTROL_SW_MODE; + writel(value, drv_data->ioaddr + offset + SPI_CS_CONTROL); + value = readl(drv_data->ioaddr + offset + SPI_CS_CONTROL); + if (value != (orig & ~SPI_CS_CONTROL_SW_MODE)) { + offset = 0x800; + goto detection_done; + } + +detection_done: + /* Now set the LPSS base */ + drv_data->lpss_base = drv_data->ioaddr + offset; + + /* Enable software chip select control */ + value = SPI_CS_CONTROL_SW_MODE | SPI_CS_CONTROL_CS_HIGH; + __lpss_ssp_write_priv(drv_data, SPI_CS_CONTROL, value); + + /* Enable multiblock DMA transfers */ + if (drv_data->master_info->enable_dma) { + __lpss_ssp_write_priv(drv_data, SSP_REG, 1); + + value = __lpss_ssp_read_priv(drv_data, GENERAL_REG); + value |= GENERAL_REG_RXTO_HOLDOFF_DISABLE; + __lpss_ssp_write_priv(drv_data, GENERAL_REG, value); + } +} + +static void lpss_ssp_cs_control(struct driver_data *drv_data, bool enable) +{ + u32 value; + + value = __lpss_ssp_read_priv(drv_data, SPI_CS_CONTROL); + if (enable) + value &= ~SPI_CS_CONTROL_CS_HIGH; + else + value |= SPI_CS_CONTROL_CS_HIGH; + __lpss_ssp_write_priv(drv_data, SPI_CS_CONTROL, value); +} + +static void cs_assert(struct driver_data *drv_data) +{ + struct chip_data *chip = drv_data->cur_chip; + + if (drv_data->ssp_type == CE4100_SSP) { + pxa2xx_spi_write(drv_data, SSSR, drv_data->cur_chip->frm); + return; + } + + if (chip->cs_control) { + chip->cs_control(PXA2XX_CS_ASSERT); + return; + } + + if (gpio_is_valid(chip->gpio_cs)) { + gpio_set_value(chip->gpio_cs, chip->gpio_cs_inverted); + return; + } + + if (is_lpss_ssp(drv_data)) + lpss_ssp_cs_control(drv_data, true); +} + +static void cs_deassert(struct driver_data *drv_data) +{ + struct chip_data *chip = drv_data->cur_chip; + + if (drv_data->ssp_type == CE4100_SSP) + return; + + if (chip->cs_control) { + chip->cs_control(PXA2XX_CS_DEASSERT); + return; + } + + if (gpio_is_valid(chip->gpio_cs)) { + gpio_set_value(chip->gpio_cs, !chip->gpio_cs_inverted); + return; + } + + if (is_lpss_ssp(drv_data)) + lpss_ssp_cs_control(drv_data, false); +} + +int pxa2xx_spi_flush(struct driver_data *drv_data) +{ + unsigned long limit = loops_per_jiffy << 1; + + do { + while (pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE) + pxa2xx_spi_read(drv_data, SSDR); + } while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_BSY) && --limit); + write_SSSR_CS(drv_data, SSSR_ROR); + + return limit; +} + +static int null_writer(struct driver_data *drv_data) +{ + u8 n_bytes = drv_data->n_bytes; + + if (pxa2xx_spi_txfifo_full(drv_data) + || (drv_data->tx == drv_data->tx_end)) + return 0; + + pxa2xx_spi_write(drv_data, SSDR, 0); + drv_data->tx += n_bytes; + + return 1; +} + +static int null_reader(struct driver_data *drv_data) +{ + u8 n_bytes = drv_data->n_bytes; + + while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE) + && (drv_data->rx < drv_data->rx_end)) { + pxa2xx_spi_read(drv_data, SSDR); + drv_data->rx += n_bytes; + } + + return drv_data->rx == drv_data->rx_end; +} + +static int u8_writer(struct driver_data *drv_data) +{ + if (pxa2xx_spi_txfifo_full(drv_data) + || (drv_data->tx == drv_data->tx_end)) + return 0; + + pxa2xx_spi_write(drv_data, SSDR, *(u8 *)(drv_data->tx)); + ++drv_data->tx; + + return 1; +} + +static int u8_reader(struct driver_data *drv_data) +{ + while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE) + && (drv_data->rx < drv_data->rx_end)) { + *(u8 *)(drv_data->rx) = pxa2xx_spi_read(drv_data, SSDR); + ++drv_data->rx; + } + + return drv_data->rx == drv_data->rx_end; +} + +static int u16_writer(struct driver_data *drv_data) +{ + if (pxa2xx_spi_txfifo_full(drv_data) + || (drv_data->tx == drv_data->tx_end)) + return 0; + + pxa2xx_spi_write(drv_data, SSDR, *(u16 *)(drv_data->tx)); + drv_data->tx += 2; + + return 1; +} + +static int u16_reader(struct driver_data *drv_data) +{ + while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE) + && (drv_data->rx < drv_data->rx_end)) { + *(u16 *)(drv_data->rx) = pxa2xx_spi_read(drv_data, SSDR); + drv_data->rx += 2; + } + + return drv_data->rx == drv_data->rx_end; +} + +static int u32_writer(struct driver_data *drv_data) +{ + if (pxa2xx_spi_txfifo_full(drv_data) + || (drv_data->tx == drv_data->tx_end)) + return 0; + + pxa2xx_spi_write(drv_data, SSDR, *(u32 *)(drv_data->tx)); + drv_data->tx += 4; + + return 1; +} + +static int u32_reader(struct driver_data *drv_data) +{ + while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE) + && (drv_data->rx < drv_data->rx_end)) { + *(u32 *)(drv_data->rx) = pxa2xx_spi_read(drv_data, SSDR); + drv_data->rx += 4; + } + + return drv_data->rx == drv_data->rx_end; +} + +void *pxa2xx_spi_next_transfer(struct driver_data *drv_data) +{ + struct spi_message *msg = drv_data->cur_msg; + struct spi_transfer *trans = drv_data->cur_transfer; + + /* Move to next transfer */ + if (trans->transfer_list.next != &msg->transfers) { + drv_data->cur_transfer = + list_entry(trans->transfer_list.next, + struct spi_transfer, + transfer_list); + return RUNNING_STATE; + } else + return DONE_STATE; +} + +/* caller already set message->status; dma and pio irqs are blocked */ +static void giveback(struct driver_data *drv_data) +{ + struct spi_transfer* last_transfer; + struct spi_message *msg; + + msg = drv_data->cur_msg; + drv_data->cur_msg = NULL; + drv_data->cur_transfer = NULL; + + last_transfer = list_last_entry(&msg->transfers, struct spi_transfer, + transfer_list); + + /* Delay if requested before any change in chip select */ + if (last_transfer->delay_usecs) + udelay(last_transfer->delay_usecs); + + /* Drop chip select UNLESS cs_change is true or we are returning + * a message with an error, or next message is for another chip + */ + if (!last_transfer->cs_change) + cs_deassert(drv_data); + else { + struct spi_message *next_msg; + + /* Holding of cs was hinted, but we need to make sure + * the next message is for the same chip. Don't waste + * time with the following tests unless this was hinted. + * + * We cannot postpone this until pump_messages, because + * after calling msg->complete (below) the driver that + * sent the current message could be unloaded, which + * could invalidate the cs_control() callback... + */ + + /* get a pointer to the next message, if any */ + next_msg = spi_get_next_queued_message(drv_data->master); + + /* see if the next and current messages point + * to the same chip + */ + if (next_msg && next_msg->spi != msg->spi) + next_msg = NULL; + if (!next_msg || msg->state == ERROR_STATE) + cs_deassert(drv_data); + } + + drv_data->cur_chip = NULL; + spi_finalize_current_message(drv_data->master); +} + +static void reset_sccr1(struct driver_data *drv_data) +{ + struct chip_data *chip = drv_data->cur_chip; + u32 sccr1_reg; + + sccr1_reg = pxa2xx_spi_read(drv_data, SSCR1) & ~drv_data->int_cr1; + sccr1_reg &= ~SSCR1_RFT; + sccr1_reg |= chip->threshold; + pxa2xx_spi_write(drv_data, SSCR1, sccr1_reg); +} + +static void int_error_stop(struct driver_data *drv_data, const char* msg) +{ + /* Stop and reset SSP */ + write_SSSR_CS(drv_data, drv_data->clear_sr); + reset_sccr1(drv_data); + if (!pxa25x_ssp_comp(drv_data)) + pxa2xx_spi_write(drv_data, SSTO, 0); + pxa2xx_spi_flush(drv_data); + pxa2xx_spi_write(drv_data, SSCR0, + pxa2xx_spi_read(drv_data, SSCR0) & ~SSCR0_SSE); + + dev_err(&drv_data->pdev->dev, "%s\n", msg); + + drv_data->cur_msg->state = ERROR_STATE; + tasklet_schedule(&drv_data->pump_transfers); +} + +static void int_transfer_complete(struct driver_data *drv_data) +{ + /* Stop SSP */ + write_SSSR_CS(drv_data, drv_data->clear_sr); + reset_sccr1(drv_data); + if (!pxa25x_ssp_comp(drv_data)) + pxa2xx_spi_write(drv_data, SSTO, 0); + + /* Update total byte transferred return count actual bytes read */ + drv_data->cur_msg->actual_length += drv_data->len - + (drv_data->rx_end - drv_data->rx); + + /* Transfer delays and chip select release are + * handled in pump_transfers or giveback + */ + + /* Move to next transfer */ + drv_data->cur_msg->state = pxa2xx_spi_next_transfer(drv_data); + + /* Schedule transfer tasklet */ + tasklet_schedule(&drv_data->pump_transfers); +} + +static irqreturn_t interrupt_transfer(struct driver_data *drv_data) +{ + u32 irq_mask = (pxa2xx_spi_read(drv_data, SSCR1) & SSCR1_TIE) ? + drv_data->mask_sr : drv_data->mask_sr & ~SSSR_TFS; + + u32 irq_status = pxa2xx_spi_read(drv_data, SSSR) & irq_mask; + + if (irq_status & SSSR_ROR) { + int_error_stop(drv_data, "interrupt_transfer: fifo overrun"); + return IRQ_HANDLED; + } + + if (irq_status & SSSR_TINT) { + pxa2xx_spi_write(drv_data, SSSR, SSSR_TINT); + if (drv_data->read(drv_data)) { + int_transfer_complete(drv_data); + return IRQ_HANDLED; + } + } + + /* Drain rx fifo, Fill tx fifo and prevent overruns */ + do { + if (drv_data->read(drv_data)) { + int_transfer_complete(drv_data); + return IRQ_HANDLED; + } + } while (drv_data->write(drv_data)); + + if (drv_data->read(drv_data)) { + int_transfer_complete(drv_data); + return IRQ_HANDLED; + } + + if (drv_data->tx == drv_data->tx_end) { + u32 bytes_left; + u32 sccr1_reg; + + sccr1_reg = pxa2xx_spi_read(drv_data, SSCR1); + sccr1_reg &= ~SSCR1_TIE; + + /* + * PXA25x_SSP has no timeout, set up rx threshould for the + * remaining RX bytes. + */ + if (pxa25x_ssp_comp(drv_data)) { + u32 rx_thre; + + pxa2xx_spi_clear_rx_thre(drv_data, &sccr1_reg); + + bytes_left = drv_data->rx_end - drv_data->rx; + switch (drv_data->n_bytes) { + case 4: + bytes_left >>= 1; + case 2: + bytes_left >>= 1; + } + + rx_thre = pxa2xx_spi_get_rx_default_thre(drv_data); + if (rx_thre > bytes_left) + rx_thre = bytes_left; + + pxa2xx_spi_set_rx_thre(drv_data, &sccr1_reg, rx_thre); + } + pxa2xx_spi_write(drv_data, SSCR1, sccr1_reg); + } + + /* We did something */ + return IRQ_HANDLED; +} + +static irqreturn_t ssp_int(int irq, void *dev_id) +{ + struct driver_data *drv_data = dev_id; + u32 sccr1_reg; + u32 mask = drv_data->mask_sr; + u32 status; + + /* + * The IRQ might be shared with other peripherals so we must first + * check that are we RPM suspended or not. If we are we assume that + * the IRQ was not for us (we shouldn't be RPM suspended when the + * interrupt is enabled). + */ + if (pm_runtime_suspended(&drv_data->pdev->dev)) + return IRQ_NONE; + + /* + * If the device is not yet in RPM suspended state and we get an + * interrupt that is meant for another device, check if status bits + * are all set to one. That means that the device is already + * powered off. + */ + status = pxa2xx_spi_read(drv_data, SSSR); + if (status == ~0) + return IRQ_NONE; + + sccr1_reg = pxa2xx_spi_read(drv_data, SSCR1); + + /* Ignore possible writes if we don't need to write */ + if (!(sccr1_reg & SSCR1_TIE)) + mask &= ~SSSR_TFS; + + if (!(status & mask)) + return IRQ_NONE; + + if (!drv_data->cur_msg) { + + pxa2xx_spi_write(drv_data, SSCR0, + pxa2xx_spi_read(drv_data, SSCR0) + & ~SSCR0_SSE); + pxa2xx_spi_write(drv_data, SSCR1, + pxa2xx_spi_read(drv_data, SSCR1) + & ~drv_data->int_cr1); + if (!pxa25x_ssp_comp(drv_data)) + pxa2xx_spi_write(drv_data, SSTO, 0); + write_SSSR_CS(drv_data, drv_data->clear_sr); + + dev_err(&drv_data->pdev->dev, + "bad message state in interrupt handler\n"); + + /* Never fail */ + return IRQ_HANDLED; + } + + return drv_data->transfer_handler(drv_data); +} + +/* + * The Quark SPI has an additional 24 bit register (DDS_CLK_RATE) to multiply + * input frequency by fractions of 2^24. It also has a divider by 5. + * + * There are formulas to get baud rate value for given input frequency and + * divider parameters, such as DDS_CLK_RATE and SCR: + * + * Fsys = 200MHz + * + * Fssp = Fsys * DDS_CLK_RATE / 2^24 (1) + * Baud rate = Fsclk = Fssp / (2 * (SCR + 1)) (2) + * + * DDS_CLK_RATE either 2^n or 2^n / 5. + * SCR is in range 0 .. 255 + * + * Divisor = 5^i * 2^j * 2 * k + * i = [0, 1] i = 1 iff j = 0 or j > 3 + * j = [0, 23] j = 0 iff i = 1 + * k = [1, 256] + * Special case: j = 0, i = 1: Divisor = 2 / 5 + * + * Accordingly to the specification the recommended values for DDS_CLK_RATE + * are: + * Case 1: 2^n, n = [0, 23] + * Case 2: 2^24 * 2 / 5 (0x666666) + * Case 3: less than or equal to 2^24 / 5 / 16 (0x33333) + * + * In all cases the lowest possible value is better. + * + * The function calculates parameters for all cases and chooses the one closest + * to the asked baud rate. + */ +static unsigned int quark_x1000_get_clk_div(int rate, u32 *dds) +{ + unsigned long xtal = 200000000; + unsigned long fref = xtal / 2; /* mandatory division by 2, + see (2) */ + /* case 3 */ + unsigned long fref1 = fref / 2; /* case 1 */ + unsigned long fref2 = fref * 2 / 5; /* case 2 */ + unsigned long scale; + unsigned long q, q1, q2; + long r, r1, r2; + u32 mul; + + /* Case 1 */ + + /* Set initial value for DDS_CLK_RATE */ + mul = (1 << 24) >> 1; + + /* Calculate initial quot */ + q1 = DIV_ROUND_CLOSEST(fref1, rate); + + /* Scale q1 if it's too big */ + if (q1 > 256) { + /* Scale q1 to range [1, 512] */ + scale = fls_long(q1 - 1); + if (scale > 9) { + q1 >>= scale - 9; + mul >>= scale - 9; + } + + /* Round the result if we have a remainder */ + q1 += q1 & 1; + } + + /* Decrease DDS_CLK_RATE as much as we can without loss in precision */ + scale = __ffs(q1); + q1 >>= scale; + mul >>= scale; + + /* Get the remainder */ + r1 = abs(fref1 / (1 << (24 - fls_long(mul))) / q1 - rate); + + /* Case 2 */ + + q2 = DIV_ROUND_CLOSEST(fref2, rate); + r2 = abs(fref2 / q2 - rate); + + /* + * Choose the best between two: less remainder we have the better. We + * can't go case 2 if q2 is greater than 256 since SCR register can + * hold only values 0 .. 255. + */ + if (r2 >= r1 || q2 > 256) { + /* case 1 is better */ + r = r1; + q = q1; + } else { + /* case 2 is better */ + r = r2; + q = q2; + mul = (1 << 24) * 2 / 5; + } + + /* Check case 3 only If the divisor is big enough */ + if (fref / rate >= 80) { + u64 fssp; + u32 m; + + /* Calculate initial quot */ + q1 = DIV_ROUND_CLOSEST(fref, rate); + m = (1 << 24) / q1; + + /* Get the remainder */ + fssp = (u64)fref * m; + do_div(fssp, 1 << 24); + r1 = abs(fssp - rate); + + /* Choose this one if it suits better */ + if (r1 < r) { + /* case 3 is better */ + q = 1; + mul = m; + } + } + + *dds = mul; + return q - 1; +} + +static unsigned int ssp_get_clk_div(struct driver_data *drv_data, int rate) +{ + unsigned long ssp_clk = drv_data->max_clk_rate; + const struct ssp_device *ssp = drv_data->ssp; + + rate = min_t(int, ssp_clk, rate); + + if (ssp->type == PXA25x_SSP || ssp->type == CE4100_SSP) + return (ssp_clk / (2 * rate) - 1) & 0xff; + else + return (ssp_clk / rate - 1) & 0xfff; +} + +static unsigned int pxa2xx_ssp_get_clk_div(struct driver_data *drv_data, + struct chip_data *chip, int rate) +{ + unsigned int clk_div; + + switch (drv_data->ssp_type) { + case QUARK_X1000_SSP: + clk_div = quark_x1000_get_clk_div(rate, &chip->dds_rate); + break; + default: + clk_div = ssp_get_clk_div(drv_data, rate); + break; + } + return clk_div << 8; +} + +static void pump_transfers(unsigned long data) +{ + struct driver_data *drv_data = (struct driver_data *)data; + struct spi_message *message = NULL; + struct spi_transfer *transfer = NULL; + struct spi_transfer *previous = NULL; + struct chip_data *chip = NULL; + u32 clk_div = 0; + u8 bits = 0; + u32 speed = 0; + u32 cr0; + u32 cr1; + u32 dma_thresh = drv_data->cur_chip->dma_threshold; + u32 dma_burst = drv_data->cur_chip->dma_burst_size; + u32 change_mask = pxa2xx_spi_get_ssrc1_change_mask(drv_data); + + /* Get current state information */ + message = drv_data->cur_msg; + transfer = drv_data->cur_transfer; + chip = drv_data->cur_chip; + + /* Handle for abort */ + if (message->state == ERROR_STATE) { + message->status = -EIO; + giveback(drv_data); + return; + } + + /* Handle end of message */ + if (message->state == DONE_STATE) { + message->status = 0; + giveback(drv_data); + return; + } + + /* Delay if requested at end of transfer before CS change */ + if (message->state == RUNNING_STATE) { + previous = list_entry(transfer->transfer_list.prev, + struct spi_transfer, + transfer_list); + if (previous->delay_usecs) + udelay(previous->delay_usecs); + + /* Drop chip select only if cs_change is requested */ + if (previous->cs_change) + cs_deassert(drv_data); + } + + /* Check if we can DMA this transfer */ + if (!pxa2xx_spi_dma_is_possible(transfer->len) && chip->enable_dma) { + + /* reject already-mapped transfers; PIO won't always work */ + if (message->is_dma_mapped + || transfer->rx_dma || transfer->tx_dma) { + dev_err(&drv_data->pdev->dev, + "pump_transfers: mapped transfer length of " + "%u is greater than %d\n", + transfer->len, MAX_DMA_LEN); + message->status = -EINVAL; + giveback(drv_data); + return; + } + + /* warn ... we force this to PIO mode */ + dev_warn_ratelimited(&message->spi->dev, + "pump_transfers: DMA disabled for transfer length %ld " + "greater than %d\n", + (long)drv_data->len, MAX_DMA_LEN); + } + + /* Setup the transfer state based on the type of transfer */ + if (pxa2xx_spi_flush(drv_data) == 0) { + dev_err(&drv_data->pdev->dev, "pump_transfers: flush failed\n"); + message->status = -EIO; + giveback(drv_data); + return; + } + drv_data->n_bytes = chip->n_bytes; + drv_data->tx = (void *)transfer->tx_buf; + drv_data->tx_end = drv_data->tx + transfer->len; + drv_data->rx = transfer->rx_buf; + drv_data->rx_end = drv_data->rx + transfer->len; + drv_data->rx_dma = transfer->rx_dma; + drv_data->tx_dma = transfer->tx_dma; + drv_data->len = transfer->len; + drv_data->write = drv_data->tx ? chip->write : null_writer; + drv_data->read = drv_data->rx ? chip->read : null_reader; + + /* Change speed and bit per word on a per transfer */ + cr0 = chip->cr0; + if (transfer->speed_hz || transfer->bits_per_word) { + + bits = chip->bits_per_word; + speed = chip->speed_hz; + + if (transfer->speed_hz) + speed = transfer->speed_hz; + + if (transfer->bits_per_word) + bits = transfer->bits_per_word; + + clk_div = pxa2xx_ssp_get_clk_div(drv_data, chip, speed); + + if (bits <= 8) { + drv_data->n_bytes = 1; + drv_data->read = drv_data->read != null_reader ? + u8_reader : null_reader; + drv_data->write = drv_data->write != null_writer ? + u8_writer : null_writer; + } else if (bits <= 16) { + drv_data->n_bytes = 2; + drv_data->read = drv_data->read != null_reader ? + u16_reader : null_reader; + drv_data->write = drv_data->write != null_writer ? + u16_writer : null_writer; + } else if (bits <= 32) { + drv_data->n_bytes = 4; + drv_data->read = drv_data->read != null_reader ? + u32_reader : null_reader; + drv_data->write = drv_data->write != null_writer ? + u32_writer : null_writer; + } + /* if bits/word is changed in dma mode, then must check the + * thresholds and burst also */ + if (chip->enable_dma) { + if (pxa2xx_spi_set_dma_burst_and_threshold(chip, + message->spi, + bits, &dma_burst, + &dma_thresh)) + dev_warn_ratelimited(&message->spi->dev, + "pump_transfers: DMA burst size reduced to match bits_per_word\n"); + } + + cr0 = pxa2xx_configure_sscr0(drv_data, clk_div, bits); + } + + message->state = RUNNING_STATE; + + drv_data->dma_mapped = 0; + if (pxa2xx_spi_dma_is_possible(drv_data->len)) + drv_data->dma_mapped = pxa2xx_spi_map_dma_buffers(drv_data); + if (drv_data->dma_mapped) { + + /* Ensure we have the correct interrupt handler */ + drv_data->transfer_handler = pxa2xx_spi_dma_transfer; + + pxa2xx_spi_dma_prepare(drv_data, dma_burst); + + /* Clear status and start DMA engine */ + cr1 = chip->cr1 | dma_thresh | drv_data->dma_cr1; + pxa2xx_spi_write(drv_data, SSSR, drv_data->clear_sr); + + pxa2xx_spi_dma_start(drv_data); + } else { + /* Ensure we have the correct interrupt handler */ + drv_data->transfer_handler = interrupt_transfer; + + /* Clear status */ + cr1 = chip->cr1 | chip->threshold | drv_data->int_cr1; + write_SSSR_CS(drv_data, drv_data->clear_sr); + } + + if (is_lpss_ssp(drv_data)) { + if ((pxa2xx_spi_read(drv_data, SSIRF) & 0xff) + != chip->lpss_rx_threshold) + pxa2xx_spi_write(drv_data, SSIRF, + chip->lpss_rx_threshold); + if ((pxa2xx_spi_read(drv_data, SSITF) & 0xffff) + != chip->lpss_tx_threshold) + pxa2xx_spi_write(drv_data, SSITF, + chip->lpss_tx_threshold); + } + + if (is_quark_x1000_ssp(drv_data) && + (pxa2xx_spi_read(drv_data, DDS_RATE) != chip->dds_rate)) + pxa2xx_spi_write(drv_data, DDS_RATE, chip->dds_rate); + + /* see if we need to reload the config registers */ + if ((pxa2xx_spi_read(drv_data, SSCR0) != cr0) + || (pxa2xx_spi_read(drv_data, SSCR1) & change_mask) + != (cr1 & change_mask)) { + /* stop the SSP, and update the other bits */ + pxa2xx_spi_write(drv_data, SSCR0, cr0 & ~SSCR0_SSE); + if (!pxa25x_ssp_comp(drv_data)) + pxa2xx_spi_write(drv_data, SSTO, chip->timeout); + /* first set CR1 without interrupt and service enables */ + pxa2xx_spi_write(drv_data, SSCR1, cr1 & change_mask); + /* restart the SSP */ + pxa2xx_spi_write(drv_data, SSCR0, cr0); + + } else { + if (!pxa25x_ssp_comp(drv_data)) + pxa2xx_spi_write(drv_data, SSTO, chip->timeout); + } + + cs_assert(drv_data); + + /* after chip select, release the data by enabling service + * requests and interrupts, without changing any mode bits */ + pxa2xx_spi_write(drv_data, SSCR1, cr1); +} + +static int pxa2xx_spi_transfer_one_message(struct spi_master *master, + struct spi_message *msg) +{ + struct driver_data *drv_data = spi_master_get_devdata(master); + + drv_data->cur_msg = msg; + /* Initial message state*/ + drv_data->cur_msg->state = START_STATE; + drv_data->cur_transfer = list_entry(drv_data->cur_msg->transfers.next, + struct spi_transfer, + transfer_list); + + /* prepare to setup the SSP, in pump_transfers, using the per + * chip configuration */ + drv_data->cur_chip = spi_get_ctldata(drv_data->cur_msg->spi); + + /* Mark as busy and launch transfers */ + tasklet_schedule(&drv_data->pump_transfers); + return 0; +} + +static int pxa2xx_spi_unprepare_transfer(struct spi_master *master) +{ + struct driver_data *drv_data = spi_master_get_devdata(master); + + /* Disable the SSP now */ + pxa2xx_spi_write(drv_data, SSCR0, + pxa2xx_spi_read(drv_data, SSCR0) & ~SSCR0_SSE); + + return 0; +} + +static int setup_cs(struct spi_device *spi, struct chip_data *chip, + struct pxa2xx_spi_chip *chip_info) +{ + int err = 0; + + if (chip == NULL || chip_info == NULL) + return 0; + + /* NOTE: setup() can be called multiple times, possibly with + * different chip_info, release previously requested GPIO + */ + if (gpio_is_valid(chip->gpio_cs)) + gpio_free(chip->gpio_cs); + + /* If (*cs_control) is provided, ignore GPIO chip select */ + if (chip_info->cs_control) { + chip->cs_control = chip_info->cs_control; + return 0; + } + + if (gpio_is_valid(chip_info->gpio_cs)) { + err = gpio_request(chip_info->gpio_cs, "SPI_CS"); + if (err) { + dev_err(&spi->dev, "failed to request chip select GPIO%d\n", + chip_info->gpio_cs); + return err; + } + + chip->gpio_cs = chip_info->gpio_cs; + chip->gpio_cs_inverted = spi->mode & SPI_CS_HIGH; + + err = gpio_direction_output(chip->gpio_cs, + !chip->gpio_cs_inverted); + } + + return err; +} + +static int setup(struct spi_device *spi) +{ + struct pxa2xx_spi_chip *chip_info = NULL; + struct chip_data *chip; + struct driver_data *drv_data = spi_master_get_devdata(spi->master); + unsigned int clk_div; + uint tx_thres, tx_hi_thres, rx_thres; + + switch (drv_data->ssp_type) { + case QUARK_X1000_SSP: + tx_thres = TX_THRESH_QUARK_X1000_DFLT; + tx_hi_thres = 0; + rx_thres = RX_THRESH_QUARK_X1000_DFLT; + break; + case LPSS_SSP: + tx_thres = LPSS_TX_LOTHRESH_DFLT; + tx_hi_thres = LPSS_TX_HITHRESH_DFLT; + rx_thres = LPSS_RX_THRESH_DFLT; + break; + default: + tx_thres = TX_THRESH_DFLT; + tx_hi_thres = 0; + rx_thres = RX_THRESH_DFLT; + break; + } + + /* Only alloc on first setup */ + chip = spi_get_ctldata(spi); + if (!chip) { + chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL); + if (!chip) + return -ENOMEM; + + if (drv_data->ssp_type == CE4100_SSP) { + if (spi->chip_select > 4) { + dev_err(&spi->dev, + "failed setup: cs number must not be > 4.\n"); + kfree(chip); + return -EINVAL; + } + + chip->frm = spi->chip_select; + } else + chip->gpio_cs = -1; + chip->enable_dma = 0; + chip->timeout = TIMOUT_DFLT; + } + + /* protocol drivers may change the chip settings, so... + * if chip_info exists, use it */ + chip_info = spi->controller_data; + + /* chip_info isn't always needed */ + chip->cr1 = 0; + if (chip_info) { + if (chip_info->timeout) + chip->timeout = chip_info->timeout; + if (chip_info->tx_threshold) + tx_thres = chip_info->tx_threshold; + if (chip_info->tx_hi_threshold) + tx_hi_thres = chip_info->tx_hi_threshold; + if (chip_info->rx_threshold) + rx_thres = chip_info->rx_threshold; + chip->enable_dma = drv_data->master_info->enable_dma; + chip->dma_threshold = 0; + if (chip_info->enable_loopback) + chip->cr1 = SSCR1_LBM; + } else if (ACPI_HANDLE(&spi->dev)) { + /* + * Slave devices enumerated from ACPI namespace don't + * usually have chip_info but we still might want to use + * DMA with them. + */ + chip->enable_dma = drv_data->master_info->enable_dma; + } + + chip->lpss_rx_threshold = SSIRF_RxThresh(rx_thres); + chip->lpss_tx_threshold = SSITF_TxLoThresh(tx_thres) + | SSITF_TxHiThresh(tx_hi_thres); + + /* set dma burst and threshold outside of chip_info path so that if + * chip_info goes away after setting chip->enable_dma, the + * burst and threshold can still respond to changes in bits_per_word */ + if (chip->enable_dma) { + /* set up legal burst and threshold for dma */ + if (pxa2xx_spi_set_dma_burst_and_threshold(chip, spi, + spi->bits_per_word, + &chip->dma_burst_size, + &chip->dma_threshold)) { + dev_warn(&spi->dev, + "in setup: DMA burst size reduced to match bits_per_word\n"); + } + } + + clk_div = pxa2xx_ssp_get_clk_div(drv_data, chip, spi->max_speed_hz); + chip->speed_hz = spi->max_speed_hz; + + chip->cr0 = pxa2xx_configure_sscr0(drv_data, clk_div, + spi->bits_per_word); + switch (drv_data->ssp_type) { + case QUARK_X1000_SSP: + chip->threshold = (QUARK_X1000_SSCR1_RxTresh(rx_thres) + & QUARK_X1000_SSCR1_RFT) + | (QUARK_X1000_SSCR1_TxTresh(tx_thres) + & QUARK_X1000_SSCR1_TFT); + break; + default: + chip->threshold = (SSCR1_RxTresh(rx_thres) & SSCR1_RFT) | + (SSCR1_TxTresh(tx_thres) & SSCR1_TFT); + break; + } + + chip->cr1 &= ~(SSCR1_SPO | SSCR1_SPH); + chip->cr1 |= (((spi->mode & SPI_CPHA) != 0) ? SSCR1_SPH : 0) + | (((spi->mode & SPI_CPOL) != 0) ? SSCR1_SPO : 0); + + if (spi->mode & SPI_LOOP) + chip->cr1 |= SSCR1_LBM; + + /* NOTE: PXA25x_SSP _could_ use external clocking ... */ + if (!pxa25x_ssp_comp(drv_data)) + dev_dbg(&spi->dev, "%ld Hz actual, %s\n", + drv_data->max_clk_rate + / (1 + ((chip->cr0 & SSCR0_SCR(0xfff)) >> 8)), + chip->enable_dma ? "DMA" : "PIO"); + else + dev_dbg(&spi->dev, "%ld Hz actual, %s\n", + drv_data->max_clk_rate / 2 + / (1 + ((chip->cr0 & SSCR0_SCR(0x0ff)) >> 8)), + chip->enable_dma ? "DMA" : "PIO"); + + if (spi->bits_per_word <= 8) { + chip->n_bytes = 1; + chip->read = u8_reader; + chip->write = u8_writer; + } else if (spi->bits_per_word <= 16) { + chip->n_bytes = 2; + chip->read = u16_reader; + chip->write = u16_writer; + } else if (spi->bits_per_word <= 32) { + if (!is_quark_x1000_ssp(drv_data)) + chip->cr0 |= SSCR0_EDSS; + chip->n_bytes = 4; + chip->read = u32_reader; + chip->write = u32_writer; + } + chip->bits_per_word = spi->bits_per_word; + + spi_set_ctldata(spi, chip); + + if (drv_data->ssp_type == CE4100_SSP) + return 0; + + return setup_cs(spi, chip, chip_info); +} + +static void cleanup(struct spi_device *spi) +{ + struct chip_data *chip = spi_get_ctldata(spi); + struct driver_data *drv_data = spi_master_get_devdata(spi->master); + + if (!chip) + return; + + if (drv_data->ssp_type != CE4100_SSP && gpio_is_valid(chip->gpio_cs)) + gpio_free(chip->gpio_cs); + + kfree(chip); +} + +#ifdef CONFIG_ACPI +static struct pxa2xx_spi_master * +pxa2xx_spi_acpi_get_pdata(struct platform_device *pdev) +{ + struct pxa2xx_spi_master *pdata; + struct acpi_device *adev; + struct ssp_device *ssp; + struct resource *res; + int devid; + + if (!ACPI_HANDLE(&pdev->dev) || + acpi_bus_get_device(ACPI_HANDLE(&pdev->dev), &adev)) + return NULL; + + pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL); + if (!pdata) + return NULL; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) + return NULL; + + ssp = &pdata->ssp; + + ssp->phys_base = res->start; + ssp->mmio_base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(ssp->mmio_base)) + return NULL; + + ssp->clk = devm_clk_get(&pdev->dev, NULL); + ssp->irq = platform_get_irq(pdev, 0); + ssp->type = LPSS_SSP; + ssp->pdev = pdev; + + ssp->port_id = -1; + if (adev->pnp.unique_id && !kstrtoint(adev->pnp.unique_id, 0, &devid)) + ssp->port_id = devid; + + pdata->num_chipselect = 1; + pdata->enable_dma = true; + + return pdata; +} + +static struct acpi_device_id pxa2xx_spi_acpi_match[] = { + { "INT33C0", 0 }, + { "INT33C1", 0 }, + { "INT3430", 0 }, + { "INT3431", 0 }, + { "80860F0E", 0 }, + { "8086228E", 0 }, + { }, +}; +MODULE_DEVICE_TABLE(acpi, pxa2xx_spi_acpi_match); +#else +static inline struct pxa2xx_spi_master * +pxa2xx_spi_acpi_get_pdata(struct platform_device *pdev) +{ + return NULL; +} +#endif + +static int pxa2xx_spi_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct pxa2xx_spi_master *platform_info; + struct spi_master *master; + struct driver_data *drv_data; + struct ssp_device *ssp; + int status; + u32 tmp; + + platform_info = dev_get_platdata(dev); + if (!platform_info) { + platform_info = pxa2xx_spi_acpi_get_pdata(pdev); + if (!platform_info) { + dev_err(&pdev->dev, "missing platform data\n"); + return -ENODEV; + } + } + + ssp = pxa_ssp_request(pdev->id, pdev->name); + if (!ssp) + ssp = &platform_info->ssp; + + if (!ssp->mmio_base) { + dev_err(&pdev->dev, "failed to get ssp\n"); + return -ENODEV; + } + + /* Allocate master with space for drv_data and null dma buffer */ + master = spi_alloc_master(dev, sizeof(struct driver_data) + 16); + if (!master) { + dev_err(&pdev->dev, "cannot alloc spi_master\n"); + pxa_ssp_free(ssp); + return -ENOMEM; + } + drv_data = spi_master_get_devdata(master); + drv_data->master = master; + drv_data->master_info = platform_info; + drv_data->pdev = pdev; + drv_data->ssp = ssp; + + master->dev.parent = &pdev->dev; + master->dev.of_node = pdev->dev.of_node; + /* the spi->mode bits understood by this driver: */ + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LOOP; + + master->bus_num = ssp->port_id; + master->num_chipselect = platform_info->num_chipselect; + master->dma_alignment = DMA_ALIGNMENT; + master->cleanup = cleanup; + master->setup = setup; + master->transfer_one_message = pxa2xx_spi_transfer_one_message; + master->unprepare_transfer_hardware = pxa2xx_spi_unprepare_transfer; + master->auto_runtime_pm = true; + + drv_data->ssp_type = ssp->type; + drv_data->null_dma_buf = (u32 *)PTR_ALIGN(&drv_data[1], DMA_ALIGNMENT); + + drv_data->ioaddr = ssp->mmio_base; + drv_data->ssdr_physical = ssp->phys_base + SSDR; + if (pxa25x_ssp_comp(drv_data)) { + switch (drv_data->ssp_type) { + case QUARK_X1000_SSP: + master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32); + break; + default: + master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 16); + break; + } + + drv_data->int_cr1 = SSCR1_TIE | SSCR1_RIE; + drv_data->dma_cr1 = 0; + drv_data->clear_sr = SSSR_ROR; + drv_data->mask_sr = SSSR_RFS | SSSR_TFS | SSSR_ROR; + } else { + master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32); + drv_data->int_cr1 = SSCR1_TIE | SSCR1_RIE | SSCR1_TINTE; + drv_data->dma_cr1 = DEFAULT_DMA_CR1; + drv_data->clear_sr = SSSR_ROR | SSSR_TINT; + drv_data->mask_sr = SSSR_TINT | SSSR_RFS | SSSR_TFS | SSSR_ROR; + } + + status = request_irq(ssp->irq, ssp_int, IRQF_SHARED, dev_name(dev), + drv_data); + if (status < 0) { + dev_err(&pdev->dev, "cannot get IRQ %d\n", ssp->irq); + goto out_error_master_alloc; + } + + /* Setup DMA if requested */ + drv_data->tx_channel = -1; + drv_data->rx_channel = -1; + if (platform_info->enable_dma) { + status = pxa2xx_spi_dma_setup(drv_data); + if (status) { + dev_dbg(dev, "no DMA channels available, using PIO\n"); + platform_info->enable_dma = false; + } + } + + /* Enable SOC clock */ + clk_prepare_enable(ssp->clk); + + drv_data->max_clk_rate = clk_get_rate(ssp->clk); + + /* Load default SSP configuration */ + pxa2xx_spi_write(drv_data, SSCR0, 0); + switch (drv_data->ssp_type) { + case QUARK_X1000_SSP: + tmp = QUARK_X1000_SSCR1_RxTresh(RX_THRESH_QUARK_X1000_DFLT) + | QUARK_X1000_SSCR1_TxTresh(TX_THRESH_QUARK_X1000_DFLT); + pxa2xx_spi_write(drv_data, SSCR1, tmp); + + /* using the Motorola SPI protocol and use 8 bit frame */ + pxa2xx_spi_write(drv_data, SSCR0, + QUARK_X1000_SSCR0_Motorola + | QUARK_X1000_SSCR0_DataSize(8)); + break; + default: + tmp = SSCR1_RxTresh(RX_THRESH_DFLT) | + SSCR1_TxTresh(TX_THRESH_DFLT); + pxa2xx_spi_write(drv_data, SSCR1, tmp); + tmp = SSCR0_SCR(2) | SSCR0_Motorola | SSCR0_DataSize(8); + pxa2xx_spi_write(drv_data, SSCR0, tmp); + break; + } + + if (!pxa25x_ssp_comp(drv_data)) + pxa2xx_spi_write(drv_data, SSTO, 0); + + if (!is_quark_x1000_ssp(drv_data)) + pxa2xx_spi_write(drv_data, SSPSP, 0); + + if (is_lpss_ssp(drv_data)) + lpss_ssp_setup(drv_data); + + tasklet_init(&drv_data->pump_transfers, pump_transfers, + (unsigned long)drv_data); + + pm_runtime_set_autosuspend_delay(&pdev->dev, 50); + pm_runtime_use_autosuspend(&pdev->dev); + pm_runtime_set_active(&pdev->dev); + pm_runtime_enable(&pdev->dev); + + /* Register with the SPI framework */ + platform_set_drvdata(pdev, drv_data); + status = devm_spi_register_master(&pdev->dev, master); + if (status != 0) { + dev_err(&pdev->dev, "problem registering spi master\n"); + goto out_error_clock_enabled; + } + + return status; + +out_error_clock_enabled: + clk_disable_unprepare(ssp->clk); + pxa2xx_spi_dma_release(drv_data); + free_irq(ssp->irq, drv_data); + +out_error_master_alloc: + spi_master_put(master); + pxa_ssp_free(ssp); + return status; +} + +static int pxa2xx_spi_remove(struct platform_device *pdev) +{ + struct driver_data *drv_data = platform_get_drvdata(pdev); + struct ssp_device *ssp; + + if (!drv_data) + return 0; + ssp = drv_data->ssp; + + pm_runtime_get_sync(&pdev->dev); + + /* Disable the SSP at the peripheral and SOC level */ + pxa2xx_spi_write(drv_data, SSCR0, 0); + clk_disable_unprepare(ssp->clk); + + /* Release DMA */ + if (drv_data->master_info->enable_dma) + pxa2xx_spi_dma_release(drv_data); + + pm_runtime_put_noidle(&pdev->dev); + pm_runtime_disable(&pdev->dev); + + /* Release IRQ */ + free_irq(ssp->irq, drv_data); + + /* Release SSP */ + pxa_ssp_free(ssp); + + return 0; +} + +static void pxa2xx_spi_shutdown(struct platform_device *pdev) +{ + int status = 0; + + if ((status = pxa2xx_spi_remove(pdev)) != 0) + dev_err(&pdev->dev, "shutdown failed with %d\n", status); +} + +#ifdef CONFIG_PM_SLEEP +static int pxa2xx_spi_suspend(struct device *dev) +{ + struct driver_data *drv_data = dev_get_drvdata(dev); + struct ssp_device *ssp = drv_data->ssp; + int status = 0; + + status = spi_master_suspend(drv_data->master); + if (status != 0) + return status; + pxa2xx_spi_write(drv_data, SSCR0, 0); + + if (!pm_runtime_suspended(dev)) + clk_disable_unprepare(ssp->clk); + + return 0; +} + +static int pxa2xx_spi_resume(struct device *dev) +{ + struct driver_data *drv_data = dev_get_drvdata(dev); + struct ssp_device *ssp = drv_data->ssp; + int status = 0; + + pxa2xx_spi_dma_resume(drv_data); + + /* Enable the SSP clock */ + if (!pm_runtime_suspended(dev)) + clk_prepare_enable(ssp->clk); + + /* Restore LPSS private register bits */ + if (is_lpss_ssp(drv_data)) + lpss_ssp_setup(drv_data); + + /* Start the queue running */ + status = spi_master_resume(drv_data->master); + if (status != 0) { + dev_err(dev, "problem starting queue (%d)\n", status); + return status; + } + + return 0; +} +#endif + +#ifdef CONFIG_PM +static int pxa2xx_spi_runtime_suspend(struct device *dev) +{ + struct driver_data *drv_data = dev_get_drvdata(dev); + + clk_disable_unprepare(drv_data->ssp->clk); + return 0; +} + +static int pxa2xx_spi_runtime_resume(struct device *dev) +{ + struct driver_data *drv_data = dev_get_drvdata(dev); + + clk_prepare_enable(drv_data->ssp->clk); + return 0; +} +#endif + +static const struct dev_pm_ops pxa2xx_spi_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(pxa2xx_spi_suspend, pxa2xx_spi_resume) + SET_RUNTIME_PM_OPS(pxa2xx_spi_runtime_suspend, + pxa2xx_spi_runtime_resume, NULL) +}; + +static struct platform_driver driver = { + .driver = { + .name = "pxa2xx-spi", + .pm = &pxa2xx_spi_pm_ops, + .acpi_match_table = ACPI_PTR(pxa2xx_spi_acpi_match), + }, + .probe = pxa2xx_spi_probe, + .remove = pxa2xx_spi_remove, + .shutdown = pxa2xx_spi_shutdown, +}; + +static int __init pxa2xx_spi_init(void) +{ + return platform_driver_register(&driver); +} +subsys_initcall(pxa2xx_spi_init); + +static void __exit pxa2xx_spi_exit(void) +{ + platform_driver_unregister(&driver); +} +module_exit(pxa2xx_spi_exit); diff --git a/drivers/spi/spi-pxa2xx.h b/drivers/spi/spi-pxa2xx.h new file mode 100644 index 000000000..85a58c906 --- /dev/null +++ b/drivers/spi/spi-pxa2xx.h @@ -0,0 +1,219 @@ +/* + * Copyright (C) 2005 Stephen Street / StreetFire Sound Labs + * Copyright (C) 2013, Intel Corporation + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#ifndef SPI_PXA2XX_H +#define SPI_PXA2XX_H + +#include <linux/atomic.h> +#include <linux/dmaengine.h> +#include <linux/errno.h> +#include <linux/io.h> +#include <linux/interrupt.h> +#include <linux/platform_device.h> +#include <linux/pxa2xx_ssp.h> +#include <linux/scatterlist.h> +#include <linux/sizes.h> +#include <linux/spi/spi.h> +#include <linux/spi/pxa2xx_spi.h> + +struct driver_data { + /* Driver model hookup */ + struct platform_device *pdev; + + /* SSP Info */ + struct ssp_device *ssp; + + /* SPI framework hookup */ + enum pxa_ssp_type ssp_type; + struct spi_master *master; + + /* PXA hookup */ + struct pxa2xx_spi_master *master_info; + + /* PXA private DMA setup stuff */ + int rx_channel; + int tx_channel; + u32 *null_dma_buf; + + /* SSP register addresses */ + void __iomem *ioaddr; + u32 ssdr_physical; + + /* SSP masks*/ + u32 dma_cr1; + u32 int_cr1; + u32 clear_sr; + u32 mask_sr; + + /* Maximun clock rate */ + unsigned long max_clk_rate; + + /* Message Transfer pump */ + struct tasklet_struct pump_transfers; + + /* DMA engine support */ + struct dma_chan *rx_chan; + struct dma_chan *tx_chan; + struct sg_table rx_sgt; + struct sg_table tx_sgt; + int rx_nents; + int tx_nents; + void *dummy; + atomic_t dma_running; + + /* Current message transfer state info */ + struct spi_message *cur_msg; + struct spi_transfer *cur_transfer; + struct chip_data *cur_chip; + size_t len; + void *tx; + void *tx_end; + void *rx; + void *rx_end; + int dma_mapped; + dma_addr_t rx_dma; + dma_addr_t tx_dma; + size_t rx_map_len; + size_t tx_map_len; + u8 n_bytes; + int (*write)(struct driver_data *drv_data); + int (*read)(struct driver_data *drv_data); + irqreturn_t (*transfer_handler)(struct driver_data *drv_data); + void (*cs_control)(u32 command); + + void __iomem *lpss_base; +}; + +struct chip_data { + u32 cr0; + u32 cr1; + u32 dds_rate; + u32 psp; + u32 timeout; + u8 n_bytes; + u32 dma_burst_size; + u32 threshold; + u32 dma_threshold; + u16 lpss_rx_threshold; + u16 lpss_tx_threshold; + u8 enable_dma; + u8 bits_per_word; + u32 speed_hz; + union { + int gpio_cs; + unsigned int frm; + }; + int gpio_cs_inverted; + int (*write)(struct driver_data *drv_data); + int (*read)(struct driver_data *drv_data); + void (*cs_control)(u32 command); +}; + +static inline u32 pxa2xx_spi_read(const struct driver_data *drv_data, + unsigned reg) +{ + return __raw_readl(drv_data->ioaddr + reg); +} + +static inline void pxa2xx_spi_write(const struct driver_data *drv_data, + unsigned reg, u32 val) +{ + __raw_writel(val, drv_data->ioaddr + reg); +} + +#define START_STATE ((void *)0) +#define RUNNING_STATE ((void *)1) +#define DONE_STATE ((void *)2) +#define ERROR_STATE ((void *)-1) + +#define IS_DMA_ALIGNED(x) IS_ALIGNED((unsigned long)(x), DMA_ALIGNMENT) +#define DMA_ALIGNMENT 8 + +static inline int pxa25x_ssp_comp(struct driver_data *drv_data) +{ + switch (drv_data->ssp_type) { + case PXA25x_SSP: + case CE4100_SSP: + case QUARK_X1000_SSP: + return 1; + default: + return 0; + } +} + +static inline void write_SSSR_CS(struct driver_data *drv_data, u32 val) +{ + if (drv_data->ssp_type == CE4100_SSP || + drv_data->ssp_type == QUARK_X1000_SSP) + val |= pxa2xx_spi_read(drv_data, SSSR) & SSSR_ALT_FRM_MASK; + + pxa2xx_spi_write(drv_data, SSSR, val); +} + +extern int pxa2xx_spi_flush(struct driver_data *drv_data); +extern void *pxa2xx_spi_next_transfer(struct driver_data *drv_data); + +/* + * Select the right DMA implementation. + */ +#if defined(CONFIG_SPI_PXA2XX_PXADMA) +#define SPI_PXA2XX_USE_DMA 1 +#define MAX_DMA_LEN 8191 +#define DEFAULT_DMA_CR1 (SSCR1_TSRE | SSCR1_RSRE | SSCR1_TINTE) +#elif defined(CONFIG_SPI_PXA2XX_DMA) +#define SPI_PXA2XX_USE_DMA 1 +#define MAX_DMA_LEN SZ_64K +#define DEFAULT_DMA_CR1 (SSCR1_TSRE | SSCR1_RSRE | SSCR1_TRAIL) +#else +#undef SPI_PXA2XX_USE_DMA +#define MAX_DMA_LEN 0 +#define DEFAULT_DMA_CR1 0 +#endif + +#ifdef SPI_PXA2XX_USE_DMA +extern bool pxa2xx_spi_dma_is_possible(size_t len); +extern int pxa2xx_spi_map_dma_buffers(struct driver_data *drv_data); +extern irqreturn_t pxa2xx_spi_dma_transfer(struct driver_data *drv_data); +extern int pxa2xx_spi_dma_prepare(struct driver_data *drv_data, u32 dma_burst); +extern void pxa2xx_spi_dma_start(struct driver_data *drv_data); +extern int pxa2xx_spi_dma_setup(struct driver_data *drv_data); +extern void pxa2xx_spi_dma_release(struct driver_data *drv_data); +extern void pxa2xx_spi_dma_resume(struct driver_data *drv_data); +extern int pxa2xx_spi_set_dma_burst_and_threshold(struct chip_data *chip, + struct spi_device *spi, + u8 bits_per_word, + u32 *burst_code, + u32 *threshold); +#else +static inline bool pxa2xx_spi_dma_is_possible(size_t len) { return false; } +static inline int pxa2xx_spi_map_dma_buffers(struct driver_data *drv_data) +{ + return 0; +} +#define pxa2xx_spi_dma_transfer NULL +static inline void pxa2xx_spi_dma_prepare(struct driver_data *drv_data, + u32 dma_burst) {} +static inline void pxa2xx_spi_dma_start(struct driver_data *drv_data) {} +static inline int pxa2xx_spi_dma_setup(struct driver_data *drv_data) +{ + return 0; +} +static inline void pxa2xx_spi_dma_release(struct driver_data *drv_data) {} +static inline void pxa2xx_spi_dma_resume(struct driver_data *drv_data) {} +static inline int pxa2xx_spi_set_dma_burst_and_threshold(struct chip_data *chip, + struct spi_device *spi, + u8 bits_per_word, + u32 *burst_code, + u32 *threshold) +{ + return -ENODEV; +} +#endif + +#endif /* SPI_PXA2XX_H */ diff --git a/drivers/spi/spi-qup.c b/drivers/spi/spi-qup.c new file mode 100644 index 000000000..810a7fae3 --- /dev/null +++ b/drivers/spi/spi-qup.c @@ -0,0 +1,1050 @@ +/* + * Copyright (c) 2008-2014, The Linux foundation. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License rev 2 and + * only rev 2 as published by the free Software foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or fITNESS fOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/err.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/list.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/spi/spi.h> +#include <linux/dmaengine.h> +#include <linux/dma-mapping.h> + +#define QUP_CONFIG 0x0000 +#define QUP_STATE 0x0004 +#define QUP_IO_M_MODES 0x0008 +#define QUP_SW_RESET 0x000c +#define QUP_OPERATIONAL 0x0018 +#define QUP_ERROR_FLAGS 0x001c +#define QUP_ERROR_FLAGS_EN 0x0020 +#define QUP_OPERATIONAL_MASK 0x0028 +#define QUP_HW_VERSION 0x0030 +#define QUP_MX_OUTPUT_CNT 0x0100 +#define QUP_OUTPUT_FIFO 0x0110 +#define QUP_MX_WRITE_CNT 0x0150 +#define QUP_MX_INPUT_CNT 0x0200 +#define QUP_MX_READ_CNT 0x0208 +#define QUP_INPUT_FIFO 0x0218 + +#define SPI_CONFIG 0x0300 +#define SPI_IO_CONTROL 0x0304 +#define SPI_ERROR_FLAGS 0x0308 +#define SPI_ERROR_FLAGS_EN 0x030c + +/* QUP_CONFIG fields */ +#define QUP_CONFIG_SPI_MODE (1 << 8) +#define QUP_CONFIG_CLOCK_AUTO_GATE BIT(13) +#define QUP_CONFIG_NO_INPUT BIT(7) +#define QUP_CONFIG_NO_OUTPUT BIT(6) +#define QUP_CONFIG_N 0x001f + +/* QUP_STATE fields */ +#define QUP_STATE_VALID BIT(2) +#define QUP_STATE_RESET 0 +#define QUP_STATE_RUN 1 +#define QUP_STATE_PAUSE 3 +#define QUP_STATE_MASK 3 +#define QUP_STATE_CLEAR 2 + +#define QUP_HW_VERSION_2_1_1 0x20010001 + +/* QUP_IO_M_MODES fields */ +#define QUP_IO_M_PACK_EN BIT(15) +#define QUP_IO_M_UNPACK_EN BIT(14) +#define QUP_IO_M_INPUT_MODE_MASK_SHIFT 12 +#define QUP_IO_M_OUTPUT_MODE_MASK_SHIFT 10 +#define QUP_IO_M_INPUT_MODE_MASK (3 << QUP_IO_M_INPUT_MODE_MASK_SHIFT) +#define QUP_IO_M_OUTPUT_MODE_MASK (3 << QUP_IO_M_OUTPUT_MODE_MASK_SHIFT) + +#define QUP_IO_M_OUTPUT_BLOCK_SIZE(x) (((x) & (0x03 << 0)) >> 0) +#define QUP_IO_M_OUTPUT_FIFO_SIZE(x) (((x) & (0x07 << 2)) >> 2) +#define QUP_IO_M_INPUT_BLOCK_SIZE(x) (((x) & (0x03 << 5)) >> 5) +#define QUP_IO_M_INPUT_FIFO_SIZE(x) (((x) & (0x07 << 7)) >> 7) + +#define QUP_IO_M_MODE_FIFO 0 +#define QUP_IO_M_MODE_BLOCK 1 +#define QUP_IO_M_MODE_DMOV 2 +#define QUP_IO_M_MODE_BAM 3 + +/* QUP_OPERATIONAL fields */ +#define QUP_OP_MAX_INPUT_DONE_FLAG BIT(11) +#define QUP_OP_MAX_OUTPUT_DONE_FLAG BIT(10) +#define QUP_OP_IN_SERVICE_FLAG BIT(9) +#define QUP_OP_OUT_SERVICE_FLAG BIT(8) +#define QUP_OP_IN_FIFO_FULL BIT(7) +#define QUP_OP_OUT_FIFO_FULL BIT(6) +#define QUP_OP_IN_FIFO_NOT_EMPTY BIT(5) +#define QUP_OP_OUT_FIFO_NOT_EMPTY BIT(4) + +/* QUP_ERROR_FLAGS and QUP_ERROR_FLAGS_EN fields */ +#define QUP_ERROR_OUTPUT_OVER_RUN BIT(5) +#define QUP_ERROR_INPUT_UNDER_RUN BIT(4) +#define QUP_ERROR_OUTPUT_UNDER_RUN BIT(3) +#define QUP_ERROR_INPUT_OVER_RUN BIT(2) + +/* SPI_CONFIG fields */ +#define SPI_CONFIG_HS_MODE BIT(10) +#define SPI_CONFIG_INPUT_FIRST BIT(9) +#define SPI_CONFIG_LOOPBACK BIT(8) + +/* SPI_IO_CONTROL fields */ +#define SPI_IO_C_FORCE_CS BIT(11) +#define SPI_IO_C_CLK_IDLE_HIGH BIT(10) +#define SPI_IO_C_MX_CS_MODE BIT(8) +#define SPI_IO_C_CS_N_POLARITY_0 BIT(4) +#define SPI_IO_C_CS_SELECT(x) (((x) & 3) << 2) +#define SPI_IO_C_CS_SELECT_MASK 0x000c +#define SPI_IO_C_TRISTATE_CS BIT(1) +#define SPI_IO_C_NO_TRI_STATE BIT(0) + +/* SPI_ERROR_FLAGS and SPI_ERROR_FLAGS_EN fields */ +#define SPI_ERROR_CLK_OVER_RUN BIT(1) +#define SPI_ERROR_CLK_UNDER_RUN BIT(0) + +#define SPI_NUM_CHIPSELECTS 4 + +#define SPI_MAX_DMA_XFER (SZ_64K - 64) + +/* high speed mode is when bus rate is greater then 26MHz */ +#define SPI_HS_MIN_RATE 26000000 +#define SPI_MAX_RATE 50000000 + +#define SPI_DELAY_THRESHOLD 1 +#define SPI_DELAY_RETRY 10 + +struct spi_qup { + void __iomem *base; + struct device *dev; + struct clk *cclk; /* core clock */ + struct clk *iclk; /* interface clock */ + int irq; + spinlock_t lock; + + int in_fifo_sz; + int out_fifo_sz; + int in_blk_sz; + int out_blk_sz; + + struct spi_transfer *xfer; + struct completion done; + int error; + int w_size; /* bytes per SPI word */ + int n_words; + int tx_bytes; + int rx_bytes; + int qup_v1; + + int use_dma; + struct dma_slave_config rx_conf; + struct dma_slave_config tx_conf; +}; + + +static inline bool spi_qup_is_valid_state(struct spi_qup *controller) +{ + u32 opstate = readl_relaxed(controller->base + QUP_STATE); + + return opstate & QUP_STATE_VALID; +} + +static int spi_qup_set_state(struct spi_qup *controller, u32 state) +{ + unsigned long loop; + u32 cur_state; + + loop = 0; + while (!spi_qup_is_valid_state(controller)) { + + usleep_range(SPI_DELAY_THRESHOLD, SPI_DELAY_THRESHOLD * 2); + + if (++loop > SPI_DELAY_RETRY) + return -EIO; + } + + if (loop) + dev_dbg(controller->dev, "invalid state for %ld,us %d\n", + loop, state); + + cur_state = readl_relaxed(controller->base + QUP_STATE); + /* + * Per spec: for PAUSE_STATE to RESET_STATE, two writes + * of (b10) are required + */ + if (((cur_state & QUP_STATE_MASK) == QUP_STATE_PAUSE) && + (state == QUP_STATE_RESET)) { + writel_relaxed(QUP_STATE_CLEAR, controller->base + QUP_STATE); + writel_relaxed(QUP_STATE_CLEAR, controller->base + QUP_STATE); + } else { + cur_state &= ~QUP_STATE_MASK; + cur_state |= state; + writel_relaxed(cur_state, controller->base + QUP_STATE); + } + + loop = 0; + while (!spi_qup_is_valid_state(controller)) { + + usleep_range(SPI_DELAY_THRESHOLD, SPI_DELAY_THRESHOLD * 2); + + if (++loop > SPI_DELAY_RETRY) + return -EIO; + } + + return 0; +} + +static void spi_qup_fifo_read(struct spi_qup *controller, + struct spi_transfer *xfer) +{ + u8 *rx_buf = xfer->rx_buf; + u32 word, state; + int idx, shift, w_size; + + w_size = controller->w_size; + + while (controller->rx_bytes < xfer->len) { + + state = readl_relaxed(controller->base + QUP_OPERATIONAL); + if (0 == (state & QUP_OP_IN_FIFO_NOT_EMPTY)) + break; + + word = readl_relaxed(controller->base + QUP_INPUT_FIFO); + + if (!rx_buf) { + controller->rx_bytes += w_size; + continue; + } + + for (idx = 0; idx < w_size; idx++, controller->rx_bytes++) { + /* + * The data format depends on bytes per SPI word: + * 4 bytes: 0x12345678 + * 2 bytes: 0x00001234 + * 1 byte : 0x00000012 + */ + shift = BITS_PER_BYTE; + shift *= (w_size - idx - 1); + rx_buf[controller->rx_bytes] = word >> shift; + } + } +} + +static void spi_qup_fifo_write(struct spi_qup *controller, + struct spi_transfer *xfer) +{ + const u8 *tx_buf = xfer->tx_buf; + u32 word, state, data; + int idx, w_size; + + w_size = controller->w_size; + + while (controller->tx_bytes < xfer->len) { + + state = readl_relaxed(controller->base + QUP_OPERATIONAL); + if (state & QUP_OP_OUT_FIFO_FULL) + break; + + word = 0; + for (idx = 0; idx < w_size; idx++, controller->tx_bytes++) { + + if (!tx_buf) { + controller->tx_bytes += w_size; + break; + } + + data = tx_buf[controller->tx_bytes]; + word |= data << (BITS_PER_BYTE * (3 - idx)); + } + + writel_relaxed(word, controller->base + QUP_OUTPUT_FIFO); + } +} + +static void spi_qup_dma_done(void *data) +{ + struct spi_qup *qup = data; + + complete(&qup->done); +} + +static int spi_qup_prep_sg(struct spi_master *master, struct spi_transfer *xfer, + enum dma_transfer_direction dir, + dma_async_tx_callback callback) +{ + struct spi_qup *qup = spi_master_get_devdata(master); + unsigned long flags = DMA_PREP_INTERRUPT | DMA_PREP_FENCE; + struct dma_async_tx_descriptor *desc; + struct scatterlist *sgl; + struct dma_chan *chan; + dma_cookie_t cookie; + unsigned int nents; + + if (dir == DMA_MEM_TO_DEV) { + chan = master->dma_tx; + nents = xfer->tx_sg.nents; + sgl = xfer->tx_sg.sgl; + } else { + chan = master->dma_rx; + nents = xfer->rx_sg.nents; + sgl = xfer->rx_sg.sgl; + } + + desc = dmaengine_prep_slave_sg(chan, sgl, nents, dir, flags); + if (!desc) + return -EINVAL; + + desc->callback = callback; + desc->callback_param = qup; + + cookie = dmaengine_submit(desc); + + return dma_submit_error(cookie); +} + +static void spi_qup_dma_terminate(struct spi_master *master, + struct spi_transfer *xfer) +{ + if (xfer->tx_buf) + dmaengine_terminate_all(master->dma_tx); + if (xfer->rx_buf) + dmaengine_terminate_all(master->dma_rx); +} + +static int spi_qup_do_dma(struct spi_master *master, struct spi_transfer *xfer) +{ + dma_async_tx_callback rx_done = NULL, tx_done = NULL; + int ret; + + if (xfer->rx_buf) + rx_done = spi_qup_dma_done; + else if (xfer->tx_buf) + tx_done = spi_qup_dma_done; + + if (xfer->rx_buf) { + ret = spi_qup_prep_sg(master, xfer, DMA_DEV_TO_MEM, rx_done); + if (ret) + return ret; + + dma_async_issue_pending(master->dma_rx); + } + + if (xfer->tx_buf) { + ret = spi_qup_prep_sg(master, xfer, DMA_MEM_TO_DEV, tx_done); + if (ret) + return ret; + + dma_async_issue_pending(master->dma_tx); + } + + return 0; +} + +static int spi_qup_do_pio(struct spi_master *master, struct spi_transfer *xfer) +{ + struct spi_qup *qup = spi_master_get_devdata(master); + int ret; + + ret = spi_qup_set_state(qup, QUP_STATE_RUN); + if (ret) { + dev_warn(qup->dev, "cannot set RUN state\n"); + return ret; + } + + ret = spi_qup_set_state(qup, QUP_STATE_PAUSE); + if (ret) { + dev_warn(qup->dev, "cannot set PAUSE state\n"); + return ret; + } + + spi_qup_fifo_write(qup, xfer); + + return 0; +} + +static irqreturn_t spi_qup_qup_irq(int irq, void *dev_id) +{ + struct spi_qup *controller = dev_id; + struct spi_transfer *xfer; + u32 opflags, qup_err, spi_err; + unsigned long flags; + int error = 0; + + spin_lock_irqsave(&controller->lock, flags); + xfer = controller->xfer; + controller->xfer = NULL; + spin_unlock_irqrestore(&controller->lock, flags); + + qup_err = readl_relaxed(controller->base + QUP_ERROR_FLAGS); + spi_err = readl_relaxed(controller->base + SPI_ERROR_FLAGS); + opflags = readl_relaxed(controller->base + QUP_OPERATIONAL); + + writel_relaxed(qup_err, controller->base + QUP_ERROR_FLAGS); + writel_relaxed(spi_err, controller->base + SPI_ERROR_FLAGS); + writel_relaxed(opflags, controller->base + QUP_OPERATIONAL); + + if (!xfer) { + dev_err_ratelimited(controller->dev, "unexpected irq %08x %08x %08x\n", + qup_err, spi_err, opflags); + return IRQ_HANDLED; + } + + if (qup_err) { + if (qup_err & QUP_ERROR_OUTPUT_OVER_RUN) + dev_warn(controller->dev, "OUTPUT_OVER_RUN\n"); + if (qup_err & QUP_ERROR_INPUT_UNDER_RUN) + dev_warn(controller->dev, "INPUT_UNDER_RUN\n"); + if (qup_err & QUP_ERROR_OUTPUT_UNDER_RUN) + dev_warn(controller->dev, "OUTPUT_UNDER_RUN\n"); + if (qup_err & QUP_ERROR_INPUT_OVER_RUN) + dev_warn(controller->dev, "INPUT_OVER_RUN\n"); + + error = -EIO; + } + + if (spi_err) { + if (spi_err & SPI_ERROR_CLK_OVER_RUN) + dev_warn(controller->dev, "CLK_OVER_RUN\n"); + if (spi_err & SPI_ERROR_CLK_UNDER_RUN) + dev_warn(controller->dev, "CLK_UNDER_RUN\n"); + + error = -EIO; + } + + if (!controller->use_dma) { + if (opflags & QUP_OP_IN_SERVICE_FLAG) + spi_qup_fifo_read(controller, xfer); + + if (opflags & QUP_OP_OUT_SERVICE_FLAG) + spi_qup_fifo_write(controller, xfer); + } + + spin_lock_irqsave(&controller->lock, flags); + controller->error = error; + controller->xfer = xfer; + spin_unlock_irqrestore(&controller->lock, flags); + + if (controller->rx_bytes == xfer->len || error) + complete(&controller->done); + + return IRQ_HANDLED; +} + +static u32 +spi_qup_get_mode(struct spi_master *master, struct spi_transfer *xfer) +{ + struct spi_qup *qup = spi_master_get_devdata(master); + u32 mode; + + qup->w_size = 4; + + if (xfer->bits_per_word <= 8) + qup->w_size = 1; + else if (xfer->bits_per_word <= 16) + qup->w_size = 2; + + qup->n_words = xfer->len / qup->w_size; + + if (qup->n_words <= (qup->in_fifo_sz / sizeof(u32))) + mode = QUP_IO_M_MODE_FIFO; + else + mode = QUP_IO_M_MODE_BLOCK; + + return mode; +} + +/* set clock freq ... bits per word */ +static int spi_qup_io_config(struct spi_device *spi, struct spi_transfer *xfer) +{ + struct spi_qup *controller = spi_master_get_devdata(spi->master); + u32 config, iomode, mode, control; + int ret, n_words; + + if (spi->mode & SPI_LOOP && xfer->len > controller->in_fifo_sz) { + dev_err(controller->dev, "too big size for loopback %d > %d\n", + xfer->len, controller->in_fifo_sz); + return -EIO; + } + + ret = clk_set_rate(controller->cclk, xfer->speed_hz); + if (ret) { + dev_err(controller->dev, "fail to set frequency %d", + xfer->speed_hz); + return -EIO; + } + + if (spi_qup_set_state(controller, QUP_STATE_RESET)) { + dev_err(controller->dev, "cannot set RESET state\n"); + return -EIO; + } + + mode = spi_qup_get_mode(spi->master, xfer); + n_words = controller->n_words; + + if (mode == QUP_IO_M_MODE_FIFO) { + writel_relaxed(n_words, controller->base + QUP_MX_READ_CNT); + writel_relaxed(n_words, controller->base + QUP_MX_WRITE_CNT); + /* must be zero for FIFO */ + writel_relaxed(0, controller->base + QUP_MX_INPUT_CNT); + writel_relaxed(0, controller->base + QUP_MX_OUTPUT_CNT); + } else if (!controller->use_dma) { + writel_relaxed(n_words, controller->base + QUP_MX_INPUT_CNT); + writel_relaxed(n_words, controller->base + QUP_MX_OUTPUT_CNT); + /* must be zero for BLOCK and BAM */ + writel_relaxed(0, controller->base + QUP_MX_READ_CNT); + writel_relaxed(0, controller->base + QUP_MX_WRITE_CNT); + } else { + mode = QUP_IO_M_MODE_BAM; + writel_relaxed(0, controller->base + QUP_MX_READ_CNT); + writel_relaxed(0, controller->base + QUP_MX_WRITE_CNT); + + if (!controller->qup_v1) { + void __iomem *input_cnt; + + input_cnt = controller->base + QUP_MX_INPUT_CNT; + /* + * for DMA transfers, both QUP_MX_INPUT_CNT and + * QUP_MX_OUTPUT_CNT must be zero to all cases but one. + * That case is a non-balanced transfer when there is + * only a rx_buf. + */ + if (xfer->tx_buf) + writel_relaxed(0, input_cnt); + else + writel_relaxed(n_words, input_cnt); + + writel_relaxed(0, controller->base + QUP_MX_OUTPUT_CNT); + } + } + + iomode = readl_relaxed(controller->base + QUP_IO_M_MODES); + /* Set input and output transfer mode */ + iomode &= ~(QUP_IO_M_INPUT_MODE_MASK | QUP_IO_M_OUTPUT_MODE_MASK); + + if (!controller->use_dma) + iomode &= ~(QUP_IO_M_PACK_EN | QUP_IO_M_UNPACK_EN); + else + iomode |= QUP_IO_M_PACK_EN | QUP_IO_M_UNPACK_EN; + + iomode |= (mode << QUP_IO_M_OUTPUT_MODE_MASK_SHIFT); + iomode |= (mode << QUP_IO_M_INPUT_MODE_MASK_SHIFT); + + writel_relaxed(iomode, controller->base + QUP_IO_M_MODES); + + control = readl_relaxed(controller->base + SPI_IO_CONTROL); + + if (spi->mode & SPI_CPOL) + control |= SPI_IO_C_CLK_IDLE_HIGH; + else + control &= ~SPI_IO_C_CLK_IDLE_HIGH; + + writel_relaxed(control, controller->base + SPI_IO_CONTROL); + + config = readl_relaxed(controller->base + SPI_CONFIG); + + if (spi->mode & SPI_LOOP) + config |= SPI_CONFIG_LOOPBACK; + else + config &= ~SPI_CONFIG_LOOPBACK; + + if (spi->mode & SPI_CPHA) + config &= ~SPI_CONFIG_INPUT_FIRST; + else + config |= SPI_CONFIG_INPUT_FIRST; + + /* + * HS_MODE improves signal stability for spi-clk high rates, + * but is invalid in loop back mode. + */ + if ((xfer->speed_hz >= SPI_HS_MIN_RATE) && !(spi->mode & SPI_LOOP)) + config |= SPI_CONFIG_HS_MODE; + else + config &= ~SPI_CONFIG_HS_MODE; + + writel_relaxed(config, controller->base + SPI_CONFIG); + + config = readl_relaxed(controller->base + QUP_CONFIG); + config &= ~(QUP_CONFIG_NO_INPUT | QUP_CONFIG_NO_OUTPUT | QUP_CONFIG_N); + config |= xfer->bits_per_word - 1; + config |= QUP_CONFIG_SPI_MODE; + + if (controller->use_dma) { + if (!xfer->tx_buf) + config |= QUP_CONFIG_NO_OUTPUT; + if (!xfer->rx_buf) + config |= QUP_CONFIG_NO_INPUT; + } + + writel_relaxed(config, controller->base + QUP_CONFIG); + + /* only write to OPERATIONAL_MASK when register is present */ + if (!controller->qup_v1) { + u32 mask = 0; + + /* + * mask INPUT and OUTPUT service flags to prevent IRQs on FIFO + * status change in BAM mode + */ + + if (mode == QUP_IO_M_MODE_BAM) + mask = QUP_OP_IN_SERVICE_FLAG | QUP_OP_OUT_SERVICE_FLAG; + + writel_relaxed(mask, controller->base + QUP_OPERATIONAL_MASK); + } + + return 0; +} + +static int spi_qup_transfer_one(struct spi_master *master, + struct spi_device *spi, + struct spi_transfer *xfer) +{ + struct spi_qup *controller = spi_master_get_devdata(master); + unsigned long timeout, flags; + int ret = -EIO; + + ret = spi_qup_io_config(spi, xfer); + if (ret) + return ret; + + timeout = DIV_ROUND_UP(xfer->speed_hz, MSEC_PER_SEC); + timeout = DIV_ROUND_UP(xfer->len * 8, timeout); + timeout = 100 * msecs_to_jiffies(timeout); + + reinit_completion(&controller->done); + + spin_lock_irqsave(&controller->lock, flags); + controller->xfer = xfer; + controller->error = 0; + controller->rx_bytes = 0; + controller->tx_bytes = 0; + spin_unlock_irqrestore(&controller->lock, flags); + + if (controller->use_dma) + ret = spi_qup_do_dma(master, xfer); + else + ret = spi_qup_do_pio(master, xfer); + + if (ret) + goto exit; + + if (spi_qup_set_state(controller, QUP_STATE_RUN)) { + dev_warn(controller->dev, "cannot set EXECUTE state\n"); + goto exit; + } + + if (!wait_for_completion_timeout(&controller->done, timeout)) + ret = -ETIMEDOUT; + +exit: + spi_qup_set_state(controller, QUP_STATE_RESET); + spin_lock_irqsave(&controller->lock, flags); + controller->xfer = NULL; + if (!ret) + ret = controller->error; + spin_unlock_irqrestore(&controller->lock, flags); + + if (ret && controller->use_dma) + spi_qup_dma_terminate(master, xfer); + + return ret; +} + +static bool spi_qup_can_dma(struct spi_master *master, struct spi_device *spi, + struct spi_transfer *xfer) +{ + struct spi_qup *qup = spi_master_get_devdata(master); + size_t dma_align = dma_get_cache_alignment(); + u32 mode; + + qup->use_dma = 0; + + if (xfer->rx_buf && (xfer->len % qup->in_blk_sz || + IS_ERR_OR_NULL(master->dma_rx) || + !IS_ALIGNED((size_t)xfer->rx_buf, dma_align))) + return false; + + if (xfer->tx_buf && (xfer->len % qup->out_blk_sz || + IS_ERR_OR_NULL(master->dma_tx) || + !IS_ALIGNED((size_t)xfer->tx_buf, dma_align))) + return false; + + mode = spi_qup_get_mode(master, xfer); + if (mode == QUP_IO_M_MODE_FIFO) + return false; + + qup->use_dma = 1; + + return true; +} + +static void spi_qup_release_dma(struct spi_master *master) +{ + if (!IS_ERR_OR_NULL(master->dma_rx)) + dma_release_channel(master->dma_rx); + if (!IS_ERR_OR_NULL(master->dma_tx)) + dma_release_channel(master->dma_tx); +} + +static int spi_qup_init_dma(struct spi_master *master, resource_size_t base) +{ + struct spi_qup *spi = spi_master_get_devdata(master); + struct dma_slave_config *rx_conf = &spi->rx_conf, + *tx_conf = &spi->tx_conf; + struct device *dev = spi->dev; + int ret; + + /* allocate dma resources, if available */ + master->dma_rx = dma_request_slave_channel_reason(dev, "rx"); + if (IS_ERR(master->dma_rx)) + return PTR_ERR(master->dma_rx); + + master->dma_tx = dma_request_slave_channel_reason(dev, "tx"); + if (IS_ERR(master->dma_tx)) { + ret = PTR_ERR(master->dma_tx); + goto err_tx; + } + + /* set DMA parameters */ + rx_conf->direction = DMA_DEV_TO_MEM; + rx_conf->device_fc = 1; + rx_conf->src_addr = base + QUP_INPUT_FIFO; + rx_conf->src_maxburst = spi->in_blk_sz; + + tx_conf->direction = DMA_MEM_TO_DEV; + tx_conf->device_fc = 1; + tx_conf->dst_addr = base + QUP_OUTPUT_FIFO; + tx_conf->dst_maxburst = spi->out_blk_sz; + + ret = dmaengine_slave_config(master->dma_rx, rx_conf); + if (ret) { + dev_err(dev, "failed to configure RX channel\n"); + goto err; + } + + ret = dmaengine_slave_config(master->dma_tx, tx_conf); + if (ret) { + dev_err(dev, "failed to configure TX channel\n"); + goto err; + } + + return 0; + +err: + dma_release_channel(master->dma_tx); +err_tx: + dma_release_channel(master->dma_rx); + return ret; +} + +static int spi_qup_probe(struct platform_device *pdev) +{ + struct spi_master *master; + struct clk *iclk, *cclk; + struct spi_qup *controller; + struct resource *res; + struct device *dev; + void __iomem *base; + u32 max_freq, iomode, num_cs; + int ret, irq, size; + + dev = &pdev->dev; + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + base = devm_ioremap_resource(dev, res); + if (IS_ERR(base)) + return PTR_ERR(base); + + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; + + cclk = devm_clk_get(dev, "core"); + if (IS_ERR(cclk)) + return PTR_ERR(cclk); + + iclk = devm_clk_get(dev, "iface"); + if (IS_ERR(iclk)) + return PTR_ERR(iclk); + + /* This is optional parameter */ + if (of_property_read_u32(dev->of_node, "spi-max-frequency", &max_freq)) + max_freq = SPI_MAX_RATE; + + if (!max_freq || max_freq > SPI_MAX_RATE) { + dev_err(dev, "invalid clock frequency %d\n", max_freq); + return -ENXIO; + } + + ret = clk_prepare_enable(cclk); + if (ret) { + dev_err(dev, "cannot enable core clock\n"); + return ret; + } + + ret = clk_prepare_enable(iclk); + if (ret) { + clk_disable_unprepare(cclk); + dev_err(dev, "cannot enable iface clock\n"); + return ret; + } + + master = spi_alloc_master(dev, sizeof(struct spi_qup)); + if (!master) { + clk_disable_unprepare(cclk); + clk_disable_unprepare(iclk); + dev_err(dev, "cannot allocate master\n"); + return -ENOMEM; + } + + /* use num-cs unless not present or out of range */ + if (of_property_read_u32(dev->of_node, "num-cs", &num_cs) || + num_cs > SPI_NUM_CHIPSELECTS) + master->num_chipselect = SPI_NUM_CHIPSELECTS; + else + master->num_chipselect = num_cs; + + master->bus_num = pdev->id; + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LOOP; + master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32); + master->max_speed_hz = max_freq; + master->transfer_one = spi_qup_transfer_one; + master->dev.of_node = pdev->dev.of_node; + master->auto_runtime_pm = true; + master->dma_alignment = dma_get_cache_alignment(); + master->max_dma_len = SPI_MAX_DMA_XFER; + + platform_set_drvdata(pdev, master); + + controller = spi_master_get_devdata(master); + + controller->dev = dev; + controller->base = base; + controller->iclk = iclk; + controller->cclk = cclk; + controller->irq = irq; + + ret = spi_qup_init_dma(master, res->start); + if (ret == -EPROBE_DEFER) + goto error; + else if (!ret) + master->can_dma = spi_qup_can_dma; + + /* set v1 flag if device is version 1 */ + if (of_device_is_compatible(dev->of_node, "qcom,spi-qup-v1.1.1")) + controller->qup_v1 = 1; + + spin_lock_init(&controller->lock); + init_completion(&controller->done); + + iomode = readl_relaxed(base + QUP_IO_M_MODES); + + size = QUP_IO_M_OUTPUT_BLOCK_SIZE(iomode); + if (size) + controller->out_blk_sz = size * 16; + else + controller->out_blk_sz = 4; + + size = QUP_IO_M_INPUT_BLOCK_SIZE(iomode); + if (size) + controller->in_blk_sz = size * 16; + else + controller->in_blk_sz = 4; + + size = QUP_IO_M_OUTPUT_FIFO_SIZE(iomode); + controller->out_fifo_sz = controller->out_blk_sz * (2 << size); + + size = QUP_IO_M_INPUT_FIFO_SIZE(iomode); + controller->in_fifo_sz = controller->in_blk_sz * (2 << size); + + dev_info(dev, "IN:block:%d, fifo:%d, OUT:block:%d, fifo:%d\n", + controller->in_blk_sz, controller->in_fifo_sz, + controller->out_blk_sz, controller->out_fifo_sz); + + writel_relaxed(1, base + QUP_SW_RESET); + + ret = spi_qup_set_state(controller, QUP_STATE_RESET); + if (ret) { + dev_err(dev, "cannot set RESET state\n"); + goto error_dma; + } + + writel_relaxed(0, base + QUP_OPERATIONAL); + writel_relaxed(0, base + QUP_IO_M_MODES); + + if (!controller->qup_v1) + writel_relaxed(0, base + QUP_OPERATIONAL_MASK); + + writel_relaxed(SPI_ERROR_CLK_UNDER_RUN | SPI_ERROR_CLK_OVER_RUN, + base + SPI_ERROR_FLAGS_EN); + + /* if earlier version of the QUP, disable INPUT_OVERRUN */ + if (controller->qup_v1) + writel_relaxed(QUP_ERROR_OUTPUT_OVER_RUN | + QUP_ERROR_INPUT_UNDER_RUN | QUP_ERROR_OUTPUT_UNDER_RUN, + base + QUP_ERROR_FLAGS_EN); + + writel_relaxed(0, base + SPI_CONFIG); + writel_relaxed(SPI_IO_C_NO_TRI_STATE, base + SPI_IO_CONTROL); + + ret = devm_request_irq(dev, irq, spi_qup_qup_irq, + IRQF_TRIGGER_HIGH, pdev->name, controller); + if (ret) + goto error_dma; + + pm_runtime_set_autosuspend_delay(dev, MSEC_PER_SEC); + pm_runtime_use_autosuspend(dev); + pm_runtime_set_active(dev); + pm_runtime_enable(dev); + + ret = devm_spi_register_master(dev, master); + if (ret) + goto disable_pm; + + return 0; + +disable_pm: + pm_runtime_disable(&pdev->dev); +error_dma: + spi_qup_release_dma(master); +error: + clk_disable_unprepare(cclk); + clk_disable_unprepare(iclk); + spi_master_put(master); + return ret; +} + +#ifdef CONFIG_PM +static int spi_qup_pm_suspend_runtime(struct device *device) +{ + struct spi_master *master = dev_get_drvdata(device); + struct spi_qup *controller = spi_master_get_devdata(master); + u32 config; + + /* Enable clocks auto gaiting */ + config = readl(controller->base + QUP_CONFIG); + config |= QUP_CONFIG_CLOCK_AUTO_GATE; + writel_relaxed(config, controller->base + QUP_CONFIG); + return 0; +} + +static int spi_qup_pm_resume_runtime(struct device *device) +{ + struct spi_master *master = dev_get_drvdata(device); + struct spi_qup *controller = spi_master_get_devdata(master); + u32 config; + + /* Disable clocks auto gaiting */ + config = readl_relaxed(controller->base + QUP_CONFIG); + config &= ~QUP_CONFIG_CLOCK_AUTO_GATE; + writel_relaxed(config, controller->base + QUP_CONFIG); + return 0; +} +#endif /* CONFIG_PM */ + +#ifdef CONFIG_PM_SLEEP +static int spi_qup_suspend(struct device *device) +{ + struct spi_master *master = dev_get_drvdata(device); + struct spi_qup *controller = spi_master_get_devdata(master); + int ret; + + ret = spi_master_suspend(master); + if (ret) + return ret; + + ret = spi_qup_set_state(controller, QUP_STATE_RESET); + if (ret) + return ret; + + clk_disable_unprepare(controller->cclk); + clk_disable_unprepare(controller->iclk); + return 0; +} + +static int spi_qup_resume(struct device *device) +{ + struct spi_master *master = dev_get_drvdata(device); + struct spi_qup *controller = spi_master_get_devdata(master); + int ret; + + ret = clk_prepare_enable(controller->iclk); + if (ret) + return ret; + + ret = clk_prepare_enable(controller->cclk); + if (ret) + return ret; + + ret = spi_qup_set_state(controller, QUP_STATE_RESET); + if (ret) + return ret; + + return spi_master_resume(master); +} +#endif /* CONFIG_PM_SLEEP */ + +static int spi_qup_remove(struct platform_device *pdev) +{ + struct spi_master *master = dev_get_drvdata(&pdev->dev); + struct spi_qup *controller = spi_master_get_devdata(master); + int ret; + + ret = pm_runtime_get_sync(&pdev->dev); + if (ret < 0) + return ret; + + ret = spi_qup_set_state(controller, QUP_STATE_RESET); + if (ret) + return ret; + + spi_qup_release_dma(master); + + clk_disable_unprepare(controller->cclk); + clk_disable_unprepare(controller->iclk); + + pm_runtime_put_noidle(&pdev->dev); + pm_runtime_disable(&pdev->dev); + return 0; +} + +static const struct of_device_id spi_qup_dt_match[] = { + { .compatible = "qcom,spi-qup-v1.1.1", }, + { .compatible = "qcom,spi-qup-v2.1.1", }, + { .compatible = "qcom,spi-qup-v2.2.1", }, + { } +}; +MODULE_DEVICE_TABLE(of, spi_qup_dt_match); + +static const struct dev_pm_ops spi_qup_dev_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(spi_qup_suspend, spi_qup_resume) + SET_RUNTIME_PM_OPS(spi_qup_pm_suspend_runtime, + spi_qup_pm_resume_runtime, + NULL) +}; + +static struct platform_driver spi_qup_driver = { + .driver = { + .name = "spi_qup", + .pm = &spi_qup_dev_pm_ops, + .of_match_table = spi_qup_dt_match, + }, + .probe = spi_qup_probe, + .remove = spi_qup_remove, +}; +module_platform_driver(spi_qup_driver); + +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:spi_qup"); diff --git a/drivers/spi/spi-rockchip.c b/drivers/spi/spi-rockchip.c new file mode 100644 index 000000000..68e7efeb9 --- /dev/null +++ b/drivers/spi/spi-rockchip.c @@ -0,0 +1,890 @@ +/* + * Copyright (c) 2014, Fuzhou Rockchip Electronics Co., Ltd + * Author: Addy Ke <addy.ke@rock-chips.com> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + */ + +#include <linux/init.h> +#include <linux/module.h> +#include <linux/clk.h> +#include <linux/err.h> +#include <linux/delay.h> +#include <linux/interrupt.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/spi/spi.h> +#include <linux/scatterlist.h> +#include <linux/of.h> +#include <linux/pm_runtime.h> +#include <linux/io.h> +#include <linux/dmaengine.h> + +#define DRIVER_NAME "rockchip-spi" + +/* SPI register offsets */ +#define ROCKCHIP_SPI_CTRLR0 0x0000 +#define ROCKCHIP_SPI_CTRLR1 0x0004 +#define ROCKCHIP_SPI_SSIENR 0x0008 +#define ROCKCHIP_SPI_SER 0x000c +#define ROCKCHIP_SPI_BAUDR 0x0010 +#define ROCKCHIP_SPI_TXFTLR 0x0014 +#define ROCKCHIP_SPI_RXFTLR 0x0018 +#define ROCKCHIP_SPI_TXFLR 0x001c +#define ROCKCHIP_SPI_RXFLR 0x0020 +#define ROCKCHIP_SPI_SR 0x0024 +#define ROCKCHIP_SPI_IPR 0x0028 +#define ROCKCHIP_SPI_IMR 0x002c +#define ROCKCHIP_SPI_ISR 0x0030 +#define ROCKCHIP_SPI_RISR 0x0034 +#define ROCKCHIP_SPI_ICR 0x0038 +#define ROCKCHIP_SPI_DMACR 0x003c +#define ROCKCHIP_SPI_DMATDLR 0x0040 +#define ROCKCHIP_SPI_DMARDLR 0x0044 +#define ROCKCHIP_SPI_TXDR 0x0400 +#define ROCKCHIP_SPI_RXDR 0x0800 + +/* Bit fields in CTRLR0 */ +#define CR0_DFS_OFFSET 0 + +#define CR0_CFS_OFFSET 2 + +#define CR0_SCPH_OFFSET 6 + +#define CR0_SCPOL_OFFSET 7 + +#define CR0_CSM_OFFSET 8 +#define CR0_CSM_KEEP 0x0 +/* ss_n be high for half sclk_out cycles */ +#define CR0_CSM_HALF 0X1 +/* ss_n be high for one sclk_out cycle */ +#define CR0_CSM_ONE 0x2 + +/* ss_n to sclk_out delay */ +#define CR0_SSD_OFFSET 10 +/* + * The period between ss_n active and + * sclk_out active is half sclk_out cycles + */ +#define CR0_SSD_HALF 0x0 +/* + * The period between ss_n active and + * sclk_out active is one sclk_out cycle + */ +#define CR0_SSD_ONE 0x1 + +#define CR0_EM_OFFSET 11 +#define CR0_EM_LITTLE 0x0 +#define CR0_EM_BIG 0x1 + +#define CR0_FBM_OFFSET 12 +#define CR0_FBM_MSB 0x0 +#define CR0_FBM_LSB 0x1 + +#define CR0_BHT_OFFSET 13 +#define CR0_BHT_16BIT 0x0 +#define CR0_BHT_8BIT 0x1 + +#define CR0_RSD_OFFSET 14 + +#define CR0_FRF_OFFSET 16 +#define CR0_FRF_SPI 0x0 +#define CR0_FRF_SSP 0x1 +#define CR0_FRF_MICROWIRE 0x2 + +#define CR0_XFM_OFFSET 18 +#define CR0_XFM_MASK (0x03 << SPI_XFM_OFFSET) +#define CR0_XFM_TR 0x0 +#define CR0_XFM_TO 0x1 +#define CR0_XFM_RO 0x2 + +#define CR0_OPM_OFFSET 20 +#define CR0_OPM_MASTER 0x0 +#define CR0_OPM_SLAVE 0x1 + +#define CR0_MTM_OFFSET 0x21 + +/* Bit fields in SER, 2bit */ +#define SER_MASK 0x3 + +/* Bit fields in SR, 5bit */ +#define SR_MASK 0x1f +#define SR_BUSY (1 << 0) +#define SR_TF_FULL (1 << 1) +#define SR_TF_EMPTY (1 << 2) +#define SR_RF_EMPTY (1 << 3) +#define SR_RF_FULL (1 << 4) + +/* Bit fields in ISR, IMR, ISR, RISR, 5bit */ +#define INT_MASK 0x1f +#define INT_TF_EMPTY (1 << 0) +#define INT_TF_OVERFLOW (1 << 1) +#define INT_RF_UNDERFLOW (1 << 2) +#define INT_RF_OVERFLOW (1 << 3) +#define INT_RF_FULL (1 << 4) + +/* Bit fields in ICR, 4bit */ +#define ICR_MASK 0x0f +#define ICR_ALL (1 << 0) +#define ICR_RF_UNDERFLOW (1 << 1) +#define ICR_RF_OVERFLOW (1 << 2) +#define ICR_TF_OVERFLOW (1 << 3) + +/* Bit fields in DMACR */ +#define RF_DMA_EN (1 << 0) +#define TF_DMA_EN (1 << 1) + +#define RXBUSY (1 << 0) +#define TXBUSY (1 << 1) + +/* sclk_out: spi master internal logic in rk3x can support 50Mhz */ +#define MAX_SCLK_OUT 50000000 + +enum rockchip_ssi_type { + SSI_MOTO_SPI = 0, + SSI_TI_SSP, + SSI_NS_MICROWIRE, +}; + +struct rockchip_spi_dma_data { + struct dma_chan *ch; + enum dma_transfer_direction direction; + dma_addr_t addr; +}; + +struct rockchip_spi { + struct device *dev; + struct spi_master *master; + + struct clk *spiclk; + struct clk *apb_pclk; + + void __iomem *regs; + /*depth of the FIFO buffer */ + u32 fifo_len; + /* max bus freq supported */ + u32 max_freq; + /* supported slave numbers */ + enum rockchip_ssi_type type; + + u16 mode; + u8 tmode; + u8 bpw; + u8 n_bytes; + u8 rsd_nsecs; + unsigned len; + u32 speed; + + const void *tx; + const void *tx_end; + void *rx; + void *rx_end; + + u32 state; + /* protect state */ + spinlock_t lock; + + struct completion xfer_completion; + + u32 use_dma; + struct sg_table tx_sg; + struct sg_table rx_sg; + struct rockchip_spi_dma_data dma_rx; + struct rockchip_spi_dma_data dma_tx; +}; + +static inline void spi_enable_chip(struct rockchip_spi *rs, int enable) +{ + writel_relaxed((enable ? 1 : 0), rs->regs + ROCKCHIP_SPI_SSIENR); +} + +static inline void spi_set_clk(struct rockchip_spi *rs, u16 div) +{ + writel_relaxed(div, rs->regs + ROCKCHIP_SPI_BAUDR); +} + +static inline void flush_fifo(struct rockchip_spi *rs) +{ + while (readl_relaxed(rs->regs + ROCKCHIP_SPI_RXFLR)) + readl_relaxed(rs->regs + ROCKCHIP_SPI_RXDR); +} + +static inline void wait_for_idle(struct rockchip_spi *rs) +{ + unsigned long timeout = jiffies + msecs_to_jiffies(5); + + do { + if (!(readl_relaxed(rs->regs + ROCKCHIP_SPI_SR) & SR_BUSY)) + return; + } while (!time_after(jiffies, timeout)); + + dev_warn(rs->dev, "spi controller is in busy state!\n"); +} + +static u32 get_fifo_len(struct rockchip_spi *rs) +{ + u32 fifo; + + for (fifo = 2; fifo < 32; fifo++) { + writel_relaxed(fifo, rs->regs + ROCKCHIP_SPI_TXFTLR); + if (fifo != readl_relaxed(rs->regs + ROCKCHIP_SPI_TXFTLR)) + break; + } + + writel_relaxed(0, rs->regs + ROCKCHIP_SPI_TXFTLR); + + return (fifo == 31) ? 0 : fifo; +} + +static inline u32 tx_max(struct rockchip_spi *rs) +{ + u32 tx_left, tx_room; + + tx_left = (rs->tx_end - rs->tx) / rs->n_bytes; + tx_room = rs->fifo_len - readl_relaxed(rs->regs + ROCKCHIP_SPI_TXFLR); + + return min(tx_left, tx_room); +} + +static inline u32 rx_max(struct rockchip_spi *rs) +{ + u32 rx_left = (rs->rx_end - rs->rx) / rs->n_bytes; + u32 rx_room = (u32)readl_relaxed(rs->regs + ROCKCHIP_SPI_RXFLR); + + return min(rx_left, rx_room); +} + +static void rockchip_spi_set_cs(struct spi_device *spi, bool enable) +{ + u32 ser; + struct rockchip_spi *rs = spi_master_get_devdata(spi->master); + + ser = readl_relaxed(rs->regs + ROCKCHIP_SPI_SER) & SER_MASK; + + /* + * drivers/spi/spi.c: + * static void spi_set_cs(struct spi_device *spi, bool enable) + * { + * if (spi->mode & SPI_CS_HIGH) + * enable = !enable; + * + * if (spi->cs_gpio >= 0) + * gpio_set_value(spi->cs_gpio, !enable); + * else if (spi->master->set_cs) + * spi->master->set_cs(spi, !enable); + * } + * + * Note: enable(rockchip_spi_set_cs) = !enable(spi_set_cs) + */ + if (!enable) + ser |= 1 << spi->chip_select; + else + ser &= ~(1 << spi->chip_select); + + writel_relaxed(ser, rs->regs + ROCKCHIP_SPI_SER); +} + +static int rockchip_spi_prepare_message(struct spi_master *master, + struct spi_message *msg) +{ + struct rockchip_spi *rs = spi_master_get_devdata(master); + struct spi_device *spi = msg->spi; + + rs->mode = spi->mode; + + return 0; +} + +static void rockchip_spi_handle_err(struct spi_master *master, + struct spi_message *msg) +{ + unsigned long flags; + struct rockchip_spi *rs = spi_master_get_devdata(master); + + spin_lock_irqsave(&rs->lock, flags); + + /* + * For DMA mode, we need terminate DMA channel and flush + * fifo for the next transfer if DMA thansfer timeout. + * handle_err() was called by core if transfer failed. + * Maybe it is reasonable for error handling here. + */ + if (rs->use_dma) { + if (rs->state & RXBUSY) { + dmaengine_terminate_all(rs->dma_rx.ch); + flush_fifo(rs); + } + + if (rs->state & TXBUSY) + dmaengine_terminate_all(rs->dma_tx.ch); + } + + spin_unlock_irqrestore(&rs->lock, flags); +} + +static int rockchip_spi_unprepare_message(struct spi_master *master, + struct spi_message *msg) +{ + struct rockchip_spi *rs = spi_master_get_devdata(master); + + spi_enable_chip(rs, 0); + + return 0; +} + +static void rockchip_spi_pio_writer(struct rockchip_spi *rs) +{ + u32 max = tx_max(rs); + u32 txw = 0; + + while (max--) { + if (rs->n_bytes == 1) + txw = *(u8 *)(rs->tx); + else + txw = *(u16 *)(rs->tx); + + writel_relaxed(txw, rs->regs + ROCKCHIP_SPI_TXDR); + rs->tx += rs->n_bytes; + } +} + +static void rockchip_spi_pio_reader(struct rockchip_spi *rs) +{ + u32 max = rx_max(rs); + u32 rxw; + + while (max--) { + rxw = readl_relaxed(rs->regs + ROCKCHIP_SPI_RXDR); + if (rs->n_bytes == 1) + *(u8 *)(rs->rx) = (u8)rxw; + else + *(u16 *)(rs->rx) = (u16)rxw; + rs->rx += rs->n_bytes; + } +} + +static int rockchip_spi_pio_transfer(struct rockchip_spi *rs) +{ + int remain = 0; + + do { + if (rs->tx) { + remain = rs->tx_end - rs->tx; + rockchip_spi_pio_writer(rs); + } + + if (rs->rx) { + remain = rs->rx_end - rs->rx; + rockchip_spi_pio_reader(rs); + } + + cpu_relax(); + } while (remain); + + /* If tx, wait until the FIFO data completely. */ + if (rs->tx) + wait_for_idle(rs); + + spi_enable_chip(rs, 0); + + return 0; +} + +static void rockchip_spi_dma_rxcb(void *data) +{ + unsigned long flags; + struct rockchip_spi *rs = data; + + spin_lock_irqsave(&rs->lock, flags); + + rs->state &= ~RXBUSY; + if (!(rs->state & TXBUSY)) { + spi_enable_chip(rs, 0); + spi_finalize_current_transfer(rs->master); + } + + spin_unlock_irqrestore(&rs->lock, flags); +} + +static void rockchip_spi_dma_txcb(void *data) +{ + unsigned long flags; + struct rockchip_spi *rs = data; + + /* Wait until the FIFO data completely. */ + wait_for_idle(rs); + + spin_lock_irqsave(&rs->lock, flags); + + rs->state &= ~TXBUSY; + if (!(rs->state & RXBUSY)) { + spi_enable_chip(rs, 0); + spi_finalize_current_transfer(rs->master); + } + + spin_unlock_irqrestore(&rs->lock, flags); +} + +static void rockchip_spi_prepare_dma(struct rockchip_spi *rs) +{ + unsigned long flags; + struct dma_slave_config rxconf, txconf; + struct dma_async_tx_descriptor *rxdesc, *txdesc; + + spin_lock_irqsave(&rs->lock, flags); + rs->state &= ~RXBUSY; + rs->state &= ~TXBUSY; + spin_unlock_irqrestore(&rs->lock, flags); + + rxdesc = NULL; + if (rs->rx) { + rxconf.direction = rs->dma_rx.direction; + rxconf.src_addr = rs->dma_rx.addr; + rxconf.src_addr_width = rs->n_bytes; + rxconf.src_maxburst = rs->n_bytes; + dmaengine_slave_config(rs->dma_rx.ch, &rxconf); + + rxdesc = dmaengine_prep_slave_sg( + rs->dma_rx.ch, + rs->rx_sg.sgl, rs->rx_sg.nents, + rs->dma_rx.direction, DMA_PREP_INTERRUPT); + + rxdesc->callback = rockchip_spi_dma_rxcb; + rxdesc->callback_param = rs; + } + + txdesc = NULL; + if (rs->tx) { + txconf.direction = rs->dma_tx.direction; + txconf.dst_addr = rs->dma_tx.addr; + txconf.dst_addr_width = rs->n_bytes; + txconf.dst_maxburst = rs->n_bytes; + dmaengine_slave_config(rs->dma_tx.ch, &txconf); + + txdesc = dmaengine_prep_slave_sg( + rs->dma_tx.ch, + rs->tx_sg.sgl, rs->tx_sg.nents, + rs->dma_tx.direction, DMA_PREP_INTERRUPT); + + txdesc->callback = rockchip_spi_dma_txcb; + txdesc->callback_param = rs; + } + + /* rx must be started before tx due to spi instinct */ + if (rxdesc) { + spin_lock_irqsave(&rs->lock, flags); + rs->state |= RXBUSY; + spin_unlock_irqrestore(&rs->lock, flags); + dmaengine_submit(rxdesc); + dma_async_issue_pending(rs->dma_rx.ch); + } + + if (txdesc) { + spin_lock_irqsave(&rs->lock, flags); + rs->state |= TXBUSY; + spin_unlock_irqrestore(&rs->lock, flags); + dmaengine_submit(txdesc); + dma_async_issue_pending(rs->dma_tx.ch); + } +} + +static void rockchip_spi_config(struct rockchip_spi *rs) +{ + u32 div = 0; + u32 dmacr = 0; + int rsd = 0; + + u32 cr0 = (CR0_BHT_8BIT << CR0_BHT_OFFSET) + | (CR0_SSD_ONE << CR0_SSD_OFFSET); + + cr0 |= (rs->n_bytes << CR0_DFS_OFFSET); + cr0 |= ((rs->mode & 0x3) << CR0_SCPH_OFFSET); + cr0 |= (rs->tmode << CR0_XFM_OFFSET); + cr0 |= (rs->type << CR0_FRF_OFFSET); + + if (rs->use_dma) { + if (rs->tx) + dmacr |= TF_DMA_EN; + if (rs->rx) + dmacr |= RF_DMA_EN; + } + + if (WARN_ON(rs->speed > MAX_SCLK_OUT)) + rs->speed = MAX_SCLK_OUT; + + /* the minimum divsor is 2 */ + if (rs->max_freq < 2 * rs->speed) { + clk_set_rate(rs->spiclk, 2 * rs->speed); + rs->max_freq = clk_get_rate(rs->spiclk); + } + + /* div doesn't support odd number */ + div = DIV_ROUND_UP(rs->max_freq, rs->speed); + div = (div + 1) & 0xfffe; + + /* Rx sample delay is expressed in parent clock cycles (max 3) */ + rsd = DIV_ROUND_CLOSEST(rs->rsd_nsecs * (rs->max_freq >> 8), + 1000000000 >> 8); + if (!rsd && rs->rsd_nsecs) { + pr_warn_once("rockchip-spi: %u Hz are too slow to express %u ns delay\n", + rs->max_freq, rs->rsd_nsecs); + } else if (rsd > 3) { + rsd = 3; + pr_warn_once("rockchip-spi: %u Hz are too fast to express %u ns delay, clamping at %u ns\n", + rs->max_freq, rs->rsd_nsecs, + rsd * 1000000000U / rs->max_freq); + } + cr0 |= rsd << CR0_RSD_OFFSET; + + writel_relaxed(cr0, rs->regs + ROCKCHIP_SPI_CTRLR0); + + writel_relaxed(rs->len - 1, rs->regs + ROCKCHIP_SPI_CTRLR1); + writel_relaxed(rs->fifo_len / 2 - 1, rs->regs + ROCKCHIP_SPI_TXFTLR); + writel_relaxed(rs->fifo_len / 2 - 1, rs->regs + ROCKCHIP_SPI_RXFTLR); + + writel_relaxed(0, rs->regs + ROCKCHIP_SPI_DMATDLR); + writel_relaxed(0, rs->regs + ROCKCHIP_SPI_DMARDLR); + writel_relaxed(dmacr, rs->regs + ROCKCHIP_SPI_DMACR); + + spi_set_clk(rs, div); + + dev_dbg(rs->dev, "cr0 0x%x, div %d\n", cr0, div); +} + +static int rockchip_spi_transfer_one( + struct spi_master *master, + struct spi_device *spi, + struct spi_transfer *xfer) +{ + int ret = 1; + struct rockchip_spi *rs = spi_master_get_devdata(master); + + WARN_ON(readl_relaxed(rs->regs + ROCKCHIP_SPI_SSIENR) && + (readl_relaxed(rs->regs + ROCKCHIP_SPI_SR) & SR_BUSY)); + + if (!xfer->tx_buf && !xfer->rx_buf) { + dev_err(rs->dev, "No buffer for transfer\n"); + return -EINVAL; + } + + rs->speed = xfer->speed_hz; + rs->bpw = xfer->bits_per_word; + rs->n_bytes = rs->bpw >> 3; + + rs->tx = xfer->tx_buf; + rs->tx_end = rs->tx + xfer->len; + rs->rx = xfer->rx_buf; + rs->rx_end = rs->rx + xfer->len; + rs->len = xfer->len; + + rs->tx_sg = xfer->tx_sg; + rs->rx_sg = xfer->rx_sg; + + if (rs->tx && rs->rx) + rs->tmode = CR0_XFM_TR; + else if (rs->tx) + rs->tmode = CR0_XFM_TO; + else if (rs->rx) + rs->tmode = CR0_XFM_RO; + + /* we need prepare dma before spi was enabled */ + if (master->can_dma && master->can_dma(master, spi, xfer)) + rs->use_dma = 1; + else + rs->use_dma = 0; + + rockchip_spi_config(rs); + + if (rs->use_dma) { + if (rs->tmode == CR0_XFM_RO) { + /* rx: dma must be prepared first */ + rockchip_spi_prepare_dma(rs); + spi_enable_chip(rs, 1); + } else { + /* tx or tr: spi must be enabled first */ + spi_enable_chip(rs, 1); + rockchip_spi_prepare_dma(rs); + } + } else { + spi_enable_chip(rs, 1); + ret = rockchip_spi_pio_transfer(rs); + } + + return ret; +} + +static bool rockchip_spi_can_dma(struct spi_master *master, + struct spi_device *spi, + struct spi_transfer *xfer) +{ + struct rockchip_spi *rs = spi_master_get_devdata(master); + + return (xfer->len > rs->fifo_len); +} + +static int rockchip_spi_probe(struct platform_device *pdev) +{ + int ret = 0; + struct rockchip_spi *rs; + struct spi_master *master; + struct resource *mem; + u32 rsd_nsecs; + + master = spi_alloc_master(&pdev->dev, sizeof(struct rockchip_spi)); + if (!master) + return -ENOMEM; + + platform_set_drvdata(pdev, master); + + rs = spi_master_get_devdata(master); + memset(rs, 0, sizeof(struct rockchip_spi)); + + /* Get basic io resource and map it */ + mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); + rs->regs = devm_ioremap_resource(&pdev->dev, mem); + if (IS_ERR(rs->regs)) { + ret = PTR_ERR(rs->regs); + goto err_ioremap_resource; + } + + rs->apb_pclk = devm_clk_get(&pdev->dev, "apb_pclk"); + if (IS_ERR(rs->apb_pclk)) { + dev_err(&pdev->dev, "Failed to get apb_pclk\n"); + ret = PTR_ERR(rs->apb_pclk); + goto err_ioremap_resource; + } + + rs->spiclk = devm_clk_get(&pdev->dev, "spiclk"); + if (IS_ERR(rs->spiclk)) { + dev_err(&pdev->dev, "Failed to get spi_pclk\n"); + ret = PTR_ERR(rs->spiclk); + goto err_ioremap_resource; + } + + ret = clk_prepare_enable(rs->apb_pclk); + if (ret) { + dev_err(&pdev->dev, "Failed to enable apb_pclk\n"); + goto err_ioremap_resource; + } + + ret = clk_prepare_enable(rs->spiclk); + if (ret) { + dev_err(&pdev->dev, "Failed to enable spi_clk\n"); + goto err_spiclk_enable; + } + + spi_enable_chip(rs, 0); + + rs->type = SSI_MOTO_SPI; + rs->master = master; + rs->dev = &pdev->dev; + rs->max_freq = clk_get_rate(rs->spiclk); + + if (!of_property_read_u32(pdev->dev.of_node, "rx-sample-delay-ns", + &rsd_nsecs)) + rs->rsd_nsecs = rsd_nsecs; + + rs->fifo_len = get_fifo_len(rs); + if (!rs->fifo_len) { + dev_err(&pdev->dev, "Failed to get fifo length\n"); + ret = -EINVAL; + goto err_get_fifo_len; + } + + spin_lock_init(&rs->lock); + + pm_runtime_set_active(&pdev->dev); + pm_runtime_enable(&pdev->dev); + + master->auto_runtime_pm = true; + master->bus_num = pdev->id; + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LOOP; + master->num_chipselect = 2; + master->dev.of_node = pdev->dev.of_node; + master->bits_per_word_mask = SPI_BPW_MASK(16) | SPI_BPW_MASK(8); + + master->set_cs = rockchip_spi_set_cs; + master->prepare_message = rockchip_spi_prepare_message; + master->unprepare_message = rockchip_spi_unprepare_message; + master->transfer_one = rockchip_spi_transfer_one; + master->handle_err = rockchip_spi_handle_err; + + rs->dma_tx.ch = dma_request_slave_channel(rs->dev, "tx"); + if (!rs->dma_tx.ch) + dev_warn(rs->dev, "Failed to request TX DMA channel\n"); + + rs->dma_rx.ch = dma_request_slave_channel(rs->dev, "rx"); + if (!rs->dma_rx.ch) { + if (rs->dma_tx.ch) { + dma_release_channel(rs->dma_tx.ch); + rs->dma_tx.ch = NULL; + } + dev_warn(rs->dev, "Failed to request RX DMA channel\n"); + } + + if (rs->dma_tx.ch && rs->dma_rx.ch) { + rs->dma_tx.addr = (dma_addr_t)(mem->start + ROCKCHIP_SPI_TXDR); + rs->dma_rx.addr = (dma_addr_t)(mem->start + ROCKCHIP_SPI_RXDR); + rs->dma_tx.direction = DMA_MEM_TO_DEV; + rs->dma_rx.direction = DMA_DEV_TO_MEM; + + master->can_dma = rockchip_spi_can_dma; + master->dma_tx = rs->dma_tx.ch; + master->dma_rx = rs->dma_rx.ch; + } + + ret = devm_spi_register_master(&pdev->dev, master); + if (ret) { + dev_err(&pdev->dev, "Failed to register master\n"); + goto err_register_master; + } + + return 0; + +err_register_master: + if (rs->dma_tx.ch) + dma_release_channel(rs->dma_tx.ch); + if (rs->dma_rx.ch) + dma_release_channel(rs->dma_rx.ch); +err_get_fifo_len: + clk_disable_unprepare(rs->spiclk); +err_spiclk_enable: + clk_disable_unprepare(rs->apb_pclk); +err_ioremap_resource: + spi_master_put(master); + + return ret; +} + +static int rockchip_spi_remove(struct platform_device *pdev) +{ + struct spi_master *master = spi_master_get(platform_get_drvdata(pdev)); + struct rockchip_spi *rs = spi_master_get_devdata(master); + + pm_runtime_disable(&pdev->dev); + + clk_disable_unprepare(rs->spiclk); + clk_disable_unprepare(rs->apb_pclk); + + if (rs->dma_tx.ch) + dma_release_channel(rs->dma_tx.ch); + if (rs->dma_rx.ch) + dma_release_channel(rs->dma_rx.ch); + + return 0; +} + +#ifdef CONFIG_PM_SLEEP +static int rockchip_spi_suspend(struct device *dev) +{ + int ret = 0; + struct spi_master *master = dev_get_drvdata(dev); + struct rockchip_spi *rs = spi_master_get_devdata(master); + + ret = spi_master_suspend(rs->master); + if (ret) + return ret; + + if (!pm_runtime_suspended(dev)) { + clk_disable_unprepare(rs->spiclk); + clk_disable_unprepare(rs->apb_pclk); + } + + return ret; +} + +static int rockchip_spi_resume(struct device *dev) +{ + int ret = 0; + struct spi_master *master = dev_get_drvdata(dev); + struct rockchip_spi *rs = spi_master_get_devdata(master); + + if (!pm_runtime_suspended(dev)) { + ret = clk_prepare_enable(rs->apb_pclk); + if (ret < 0) + return ret; + + ret = clk_prepare_enable(rs->spiclk); + if (ret < 0) { + clk_disable_unprepare(rs->apb_pclk); + return ret; + } + } + + ret = spi_master_resume(rs->master); + if (ret < 0) { + clk_disable_unprepare(rs->spiclk); + clk_disable_unprepare(rs->apb_pclk); + } + + return ret; +} +#endif /* CONFIG_PM_SLEEP */ + +#ifdef CONFIG_PM +static int rockchip_spi_runtime_suspend(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct rockchip_spi *rs = spi_master_get_devdata(master); + + clk_disable_unprepare(rs->spiclk); + clk_disable_unprepare(rs->apb_pclk); + + return 0; +} + +static int rockchip_spi_runtime_resume(struct device *dev) +{ + int ret; + struct spi_master *master = dev_get_drvdata(dev); + struct rockchip_spi *rs = spi_master_get_devdata(master); + + ret = clk_prepare_enable(rs->apb_pclk); + if (ret) + return ret; + + ret = clk_prepare_enable(rs->spiclk); + if (ret) + clk_disable_unprepare(rs->apb_pclk); + + return ret; +} +#endif /* CONFIG_PM */ + +static const struct dev_pm_ops rockchip_spi_pm = { + SET_SYSTEM_SLEEP_PM_OPS(rockchip_spi_suspend, rockchip_spi_resume) + SET_RUNTIME_PM_OPS(rockchip_spi_runtime_suspend, + rockchip_spi_runtime_resume, NULL) +}; + +static const struct of_device_id rockchip_spi_dt_match[] = { + { .compatible = "rockchip,rk3066-spi", }, + { .compatible = "rockchip,rk3188-spi", }, + { .compatible = "rockchip,rk3288-spi", }, + { }, +}; +MODULE_DEVICE_TABLE(of, rockchip_spi_dt_match); + +static struct platform_driver rockchip_spi_driver = { + .driver = { + .name = DRIVER_NAME, + .pm = &rockchip_spi_pm, + .of_match_table = of_match_ptr(rockchip_spi_dt_match), + }, + .probe = rockchip_spi_probe, + .remove = rockchip_spi_remove, +}; + +module_platform_driver(rockchip_spi_driver); + +MODULE_AUTHOR("Addy Ke <addy.ke@rock-chips.com>"); +MODULE_DESCRIPTION("ROCKCHIP SPI Controller Driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/spi/spi-rspi.c b/drivers/spi/spi-rspi.c new file mode 100644 index 000000000..f6bac9e77 --- /dev/null +++ b/drivers/spi/spi-rspi.c @@ -0,0 +1,1326 @@ +/* + * SH RSPI driver + * + * Copyright (C) 2012, 2013 Renesas Solutions Corp. + * Copyright (C) 2014 Glider bvba + * + * Based on spi-sh.c: + * Copyright (C) 2011 Renesas Solutions Corp. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; version 2 of the License. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/sched.h> +#include <linux/errno.h> +#include <linux/interrupt.h> +#include <linux/platform_device.h> +#include <linux/io.h> +#include <linux/clk.h> +#include <linux/dmaengine.h> +#include <linux/dma-mapping.h> +#include <linux/of_device.h> +#include <linux/pm_runtime.h> +#include <linux/sh_dma.h> +#include <linux/spi/spi.h> +#include <linux/spi/rspi.h> + +#define RSPI_SPCR 0x00 /* Control Register */ +#define RSPI_SSLP 0x01 /* Slave Select Polarity Register */ +#define RSPI_SPPCR 0x02 /* Pin Control Register */ +#define RSPI_SPSR 0x03 /* Status Register */ +#define RSPI_SPDR 0x04 /* Data Register */ +#define RSPI_SPSCR 0x08 /* Sequence Control Register */ +#define RSPI_SPSSR 0x09 /* Sequence Status Register */ +#define RSPI_SPBR 0x0a /* Bit Rate Register */ +#define RSPI_SPDCR 0x0b /* Data Control Register */ +#define RSPI_SPCKD 0x0c /* Clock Delay Register */ +#define RSPI_SSLND 0x0d /* Slave Select Negation Delay Register */ +#define RSPI_SPND 0x0e /* Next-Access Delay Register */ +#define RSPI_SPCR2 0x0f /* Control Register 2 (SH only) */ +#define RSPI_SPCMD0 0x10 /* Command Register 0 */ +#define RSPI_SPCMD1 0x12 /* Command Register 1 */ +#define RSPI_SPCMD2 0x14 /* Command Register 2 */ +#define RSPI_SPCMD3 0x16 /* Command Register 3 */ +#define RSPI_SPCMD4 0x18 /* Command Register 4 */ +#define RSPI_SPCMD5 0x1a /* Command Register 5 */ +#define RSPI_SPCMD6 0x1c /* Command Register 6 */ +#define RSPI_SPCMD7 0x1e /* Command Register 7 */ +#define RSPI_SPCMD(i) (RSPI_SPCMD0 + (i) * 2) +#define RSPI_NUM_SPCMD 8 +#define RSPI_RZ_NUM_SPCMD 4 +#define QSPI_NUM_SPCMD 4 + +/* RSPI on RZ only */ +#define RSPI_SPBFCR 0x20 /* Buffer Control Register */ +#define RSPI_SPBFDR 0x22 /* Buffer Data Count Setting Register */ + +/* QSPI only */ +#define QSPI_SPBFCR 0x18 /* Buffer Control Register */ +#define QSPI_SPBDCR 0x1a /* Buffer Data Count Register */ +#define QSPI_SPBMUL0 0x1c /* Transfer Data Length Multiplier Setting Register 0 */ +#define QSPI_SPBMUL1 0x20 /* Transfer Data Length Multiplier Setting Register 1 */ +#define QSPI_SPBMUL2 0x24 /* Transfer Data Length Multiplier Setting Register 2 */ +#define QSPI_SPBMUL3 0x28 /* Transfer Data Length Multiplier Setting Register 3 */ +#define QSPI_SPBMUL(i) (QSPI_SPBMUL0 + (i) * 4) + +/* SPCR - Control Register */ +#define SPCR_SPRIE 0x80 /* Receive Interrupt Enable */ +#define SPCR_SPE 0x40 /* Function Enable */ +#define SPCR_SPTIE 0x20 /* Transmit Interrupt Enable */ +#define SPCR_SPEIE 0x10 /* Error Interrupt Enable */ +#define SPCR_MSTR 0x08 /* Master/Slave Mode Select */ +#define SPCR_MODFEN 0x04 /* Mode Fault Error Detection Enable */ +/* RSPI on SH only */ +#define SPCR_TXMD 0x02 /* TX Only Mode (vs. Full Duplex) */ +#define SPCR_SPMS 0x01 /* 3-wire Mode (vs. 4-wire) */ +/* QSPI on R-Car Gen2 only */ +#define SPCR_WSWAP 0x02 /* Word Swap of read-data for DMAC */ +#define SPCR_BSWAP 0x01 /* Byte Swap of read-data for DMAC */ + +/* SSLP - Slave Select Polarity Register */ +#define SSLP_SSL1P 0x02 /* SSL1 Signal Polarity Setting */ +#define SSLP_SSL0P 0x01 /* SSL0 Signal Polarity Setting */ + +/* SPPCR - Pin Control Register */ +#define SPPCR_MOIFE 0x20 /* MOSI Idle Value Fixing Enable */ +#define SPPCR_MOIFV 0x10 /* MOSI Idle Fixed Value */ +#define SPPCR_SPOM 0x04 +#define SPPCR_SPLP2 0x02 /* Loopback Mode 2 (non-inverting) */ +#define SPPCR_SPLP 0x01 /* Loopback Mode (inverting) */ + +#define SPPCR_IO3FV 0x04 /* Single-/Dual-SPI Mode IO3 Output Fixed Value */ +#define SPPCR_IO2FV 0x04 /* Single-/Dual-SPI Mode IO2 Output Fixed Value */ + +/* SPSR - Status Register */ +#define SPSR_SPRF 0x80 /* Receive Buffer Full Flag */ +#define SPSR_TEND 0x40 /* Transmit End */ +#define SPSR_SPTEF 0x20 /* Transmit Buffer Empty Flag */ +#define SPSR_PERF 0x08 /* Parity Error Flag */ +#define SPSR_MODF 0x04 /* Mode Fault Error Flag */ +#define SPSR_IDLNF 0x02 /* RSPI Idle Flag */ +#define SPSR_OVRF 0x01 /* Overrun Error Flag (RSPI only) */ + +/* SPSCR - Sequence Control Register */ +#define SPSCR_SPSLN_MASK 0x07 /* Sequence Length Specification */ + +/* SPSSR - Sequence Status Register */ +#define SPSSR_SPECM_MASK 0x70 /* Command Error Mask */ +#define SPSSR_SPCP_MASK 0x07 /* Command Pointer Mask */ + +/* SPDCR - Data Control Register */ +#define SPDCR_TXDMY 0x80 /* Dummy Data Transmission Enable */ +#define SPDCR_SPLW1 0x40 /* Access Width Specification (RZ) */ +#define SPDCR_SPLW0 0x20 /* Access Width Specification (RZ) */ +#define SPDCR_SPLLWORD (SPDCR_SPLW1 | SPDCR_SPLW0) +#define SPDCR_SPLWORD SPDCR_SPLW1 +#define SPDCR_SPLBYTE SPDCR_SPLW0 +#define SPDCR_SPLW 0x20 /* Access Width Specification (SH) */ +#define SPDCR_SPRDTD 0x10 /* Receive Transmit Data Select (SH) */ +#define SPDCR_SLSEL1 0x08 +#define SPDCR_SLSEL0 0x04 +#define SPDCR_SLSEL_MASK 0x0c /* SSL1 Output Select (SH) */ +#define SPDCR_SPFC1 0x02 +#define SPDCR_SPFC0 0x01 +#define SPDCR_SPFC_MASK 0x03 /* Frame Count Setting (1-4) (SH) */ + +/* SPCKD - Clock Delay Register */ +#define SPCKD_SCKDL_MASK 0x07 /* Clock Delay Setting (1-8) */ + +/* SSLND - Slave Select Negation Delay Register */ +#define SSLND_SLNDL_MASK 0x07 /* SSL Negation Delay Setting (1-8) */ + +/* SPND - Next-Access Delay Register */ +#define SPND_SPNDL_MASK 0x07 /* Next-Access Delay Setting (1-8) */ + +/* SPCR2 - Control Register 2 */ +#define SPCR2_PTE 0x08 /* Parity Self-Test Enable */ +#define SPCR2_SPIE 0x04 /* Idle Interrupt Enable */ +#define SPCR2_SPOE 0x02 /* Odd Parity Enable (vs. Even) */ +#define SPCR2_SPPE 0x01 /* Parity Enable */ + +/* SPCMDn - Command Registers */ +#define SPCMD_SCKDEN 0x8000 /* Clock Delay Setting Enable */ +#define SPCMD_SLNDEN 0x4000 /* SSL Negation Delay Setting Enable */ +#define SPCMD_SPNDEN 0x2000 /* Next-Access Delay Enable */ +#define SPCMD_LSBF 0x1000 /* LSB First */ +#define SPCMD_SPB_MASK 0x0f00 /* Data Length Setting */ +#define SPCMD_SPB_8_TO_16(bit) (((bit - 1) << 8) & SPCMD_SPB_MASK) +#define SPCMD_SPB_8BIT 0x0000 /* QSPI only */ +#define SPCMD_SPB_16BIT 0x0100 +#define SPCMD_SPB_20BIT 0x0000 +#define SPCMD_SPB_24BIT 0x0100 +#define SPCMD_SPB_32BIT 0x0200 +#define SPCMD_SSLKP 0x0080 /* SSL Signal Level Keeping */ +#define SPCMD_SPIMOD_MASK 0x0060 /* SPI Operating Mode (QSPI only) */ +#define SPCMD_SPIMOD1 0x0040 +#define SPCMD_SPIMOD0 0x0020 +#define SPCMD_SPIMOD_SINGLE 0 +#define SPCMD_SPIMOD_DUAL SPCMD_SPIMOD0 +#define SPCMD_SPIMOD_QUAD SPCMD_SPIMOD1 +#define SPCMD_SPRW 0x0010 /* SPI Read/Write Access (Dual/Quad) */ +#define SPCMD_SSLA_MASK 0x0030 /* SSL Assert Signal Setting (RSPI) */ +#define SPCMD_BRDV_MASK 0x000c /* Bit Rate Division Setting */ +#define SPCMD_CPOL 0x0002 /* Clock Polarity Setting */ +#define SPCMD_CPHA 0x0001 /* Clock Phase Setting */ + +/* SPBFCR - Buffer Control Register */ +#define SPBFCR_TXRST 0x80 /* Transmit Buffer Data Reset */ +#define SPBFCR_RXRST 0x40 /* Receive Buffer Data Reset */ +#define SPBFCR_TXTRG_MASK 0x30 /* Transmit Buffer Data Triggering Number */ +#define SPBFCR_RXTRG_MASK 0x07 /* Receive Buffer Data Triggering Number */ +/* QSPI on R-Car Gen2 */ +#define SPBFCR_TXTRG_1B 0x00 /* 31 bytes (1 byte available) */ +#define SPBFCR_TXTRG_32B 0x30 /* 0 byte (32 bytes available) */ +#define SPBFCR_RXTRG_1B 0x00 /* 1 byte (31 bytes available) */ +#define SPBFCR_RXTRG_32B 0x07 /* 32 bytes (0 byte available) */ + +#define QSPI_BUFFER_SIZE 32u + +struct rspi_data { + void __iomem *addr; + u32 max_speed_hz; + struct spi_master *master; + wait_queue_head_t wait; + struct clk *clk; + u16 spcmd; + u8 spsr; + u8 sppcr; + int rx_irq, tx_irq; + const struct spi_ops *ops; + + unsigned dma_callbacked:1; + unsigned byte_access:1; +}; + +static void rspi_write8(const struct rspi_data *rspi, u8 data, u16 offset) +{ + iowrite8(data, rspi->addr + offset); +} + +static void rspi_write16(const struct rspi_data *rspi, u16 data, u16 offset) +{ + iowrite16(data, rspi->addr + offset); +} + +static void rspi_write32(const struct rspi_data *rspi, u32 data, u16 offset) +{ + iowrite32(data, rspi->addr + offset); +} + +static u8 rspi_read8(const struct rspi_data *rspi, u16 offset) +{ + return ioread8(rspi->addr + offset); +} + +static u16 rspi_read16(const struct rspi_data *rspi, u16 offset) +{ + return ioread16(rspi->addr + offset); +} + +static void rspi_write_data(const struct rspi_data *rspi, u16 data) +{ + if (rspi->byte_access) + rspi_write8(rspi, data, RSPI_SPDR); + else /* 16 bit */ + rspi_write16(rspi, data, RSPI_SPDR); +} + +static u16 rspi_read_data(const struct rspi_data *rspi) +{ + if (rspi->byte_access) + return rspi_read8(rspi, RSPI_SPDR); + else /* 16 bit */ + return rspi_read16(rspi, RSPI_SPDR); +} + +/* optional functions */ +struct spi_ops { + int (*set_config_register)(struct rspi_data *rspi, int access_size); + int (*transfer_one)(struct spi_master *master, struct spi_device *spi, + struct spi_transfer *xfer); + u16 mode_bits; + u16 flags; + u16 fifo_size; +}; + +/* + * functions for RSPI on legacy SH + */ +static int rspi_set_config_register(struct rspi_data *rspi, int access_size) +{ + int spbr; + + /* Sets output mode, MOSI signal, and (optionally) loopback */ + rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR); + + /* Sets transfer bit rate */ + spbr = DIV_ROUND_UP(clk_get_rate(rspi->clk), + 2 * rspi->max_speed_hz) - 1; + rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR); + + /* Disable dummy transmission, set 16-bit word access, 1 frame */ + rspi_write8(rspi, 0, RSPI_SPDCR); + rspi->byte_access = 0; + + /* Sets RSPCK, SSL, next-access delay value */ + rspi_write8(rspi, 0x00, RSPI_SPCKD); + rspi_write8(rspi, 0x00, RSPI_SSLND); + rspi_write8(rspi, 0x00, RSPI_SPND); + + /* Sets parity, interrupt mask */ + rspi_write8(rspi, 0x00, RSPI_SPCR2); + + /* Sets SPCMD */ + rspi->spcmd |= SPCMD_SPB_8_TO_16(access_size); + rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0); + + /* Sets RSPI mode */ + rspi_write8(rspi, SPCR_MSTR, RSPI_SPCR); + + return 0; +} + +/* + * functions for RSPI on RZ + */ +static int rspi_rz_set_config_register(struct rspi_data *rspi, int access_size) +{ + int spbr; + + /* Sets output mode, MOSI signal, and (optionally) loopback */ + rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR); + + /* Sets transfer bit rate */ + spbr = DIV_ROUND_UP(clk_get_rate(rspi->clk), + 2 * rspi->max_speed_hz) - 1; + rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR); + + /* Disable dummy transmission, set byte access */ + rspi_write8(rspi, SPDCR_SPLBYTE, RSPI_SPDCR); + rspi->byte_access = 1; + + /* Sets RSPCK, SSL, next-access delay value */ + rspi_write8(rspi, 0x00, RSPI_SPCKD); + rspi_write8(rspi, 0x00, RSPI_SSLND); + rspi_write8(rspi, 0x00, RSPI_SPND); + + /* Sets SPCMD */ + rspi->spcmd |= SPCMD_SPB_8_TO_16(access_size); + rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0); + + /* Sets RSPI mode */ + rspi_write8(rspi, SPCR_MSTR, RSPI_SPCR); + + return 0; +} + +/* + * functions for QSPI + */ +static int qspi_set_config_register(struct rspi_data *rspi, int access_size) +{ + int spbr; + + /* Sets output mode, MOSI signal, and (optionally) loopback */ + rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR); + + /* Sets transfer bit rate */ + spbr = DIV_ROUND_UP(clk_get_rate(rspi->clk), 2 * rspi->max_speed_hz); + rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR); + + /* Disable dummy transmission, set byte access */ + rspi_write8(rspi, 0, RSPI_SPDCR); + rspi->byte_access = 1; + + /* Sets RSPCK, SSL, next-access delay value */ + rspi_write8(rspi, 0x00, RSPI_SPCKD); + rspi_write8(rspi, 0x00, RSPI_SSLND); + rspi_write8(rspi, 0x00, RSPI_SPND); + + /* Data Length Setting */ + if (access_size == 8) + rspi->spcmd |= SPCMD_SPB_8BIT; + else if (access_size == 16) + rspi->spcmd |= SPCMD_SPB_16BIT; + else + rspi->spcmd |= SPCMD_SPB_32BIT; + + rspi->spcmd |= SPCMD_SCKDEN | SPCMD_SLNDEN | SPCMD_SPNDEN; + + /* Resets transfer data length */ + rspi_write32(rspi, 0, QSPI_SPBMUL0); + + /* Resets transmit and receive buffer */ + rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, QSPI_SPBFCR); + /* Sets buffer to allow normal operation */ + rspi_write8(rspi, 0x00, QSPI_SPBFCR); + + /* Sets SPCMD */ + rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0); + + /* Enables SPI function in master mode */ + rspi_write8(rspi, SPCR_SPE | SPCR_MSTR, RSPI_SPCR); + + return 0; +} + +static void qspi_update(const struct rspi_data *rspi, u8 mask, u8 val, u8 reg) +{ + u8 data; + + data = rspi_read8(rspi, reg); + data &= ~mask; + data |= (val & mask); + rspi_write8(rspi, data, reg); +} + +static int qspi_set_send_trigger(struct rspi_data *rspi, unsigned int len) +{ + unsigned int n; + + n = min(len, QSPI_BUFFER_SIZE); + + if (len >= QSPI_BUFFER_SIZE) { + /* sets triggering number to 32 bytes */ + qspi_update(rspi, SPBFCR_TXTRG_MASK, + SPBFCR_TXTRG_32B, QSPI_SPBFCR); + } else { + /* sets triggering number to 1 byte */ + qspi_update(rspi, SPBFCR_TXTRG_MASK, + SPBFCR_TXTRG_1B, QSPI_SPBFCR); + } + + return n; +} + +static void qspi_set_receive_trigger(struct rspi_data *rspi, unsigned int len) +{ + unsigned int n; + + n = min(len, QSPI_BUFFER_SIZE); + + if (len >= QSPI_BUFFER_SIZE) { + /* sets triggering number to 32 bytes */ + qspi_update(rspi, SPBFCR_RXTRG_MASK, + SPBFCR_RXTRG_32B, QSPI_SPBFCR); + } else { + /* sets triggering number to 1 byte */ + qspi_update(rspi, SPBFCR_RXTRG_MASK, + SPBFCR_RXTRG_1B, QSPI_SPBFCR); + } +} + +#define set_config_register(spi, n) spi->ops->set_config_register(spi, n) + +static void rspi_enable_irq(const struct rspi_data *rspi, u8 enable) +{ + rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | enable, RSPI_SPCR); +} + +static void rspi_disable_irq(const struct rspi_data *rspi, u8 disable) +{ + rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~disable, RSPI_SPCR); +} + +static int rspi_wait_for_interrupt(struct rspi_data *rspi, u8 wait_mask, + u8 enable_bit) +{ + int ret; + + rspi->spsr = rspi_read8(rspi, RSPI_SPSR); + if (rspi->spsr & wait_mask) + return 0; + + rspi_enable_irq(rspi, enable_bit); + ret = wait_event_timeout(rspi->wait, rspi->spsr & wait_mask, HZ); + if (ret == 0 && !(rspi->spsr & wait_mask)) + return -ETIMEDOUT; + + return 0; +} + +static inline int rspi_wait_for_tx_empty(struct rspi_data *rspi) +{ + return rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE); +} + +static inline int rspi_wait_for_rx_full(struct rspi_data *rspi) +{ + return rspi_wait_for_interrupt(rspi, SPSR_SPRF, SPCR_SPRIE); +} + +static int rspi_data_out(struct rspi_data *rspi, u8 data) +{ + int error = rspi_wait_for_tx_empty(rspi); + if (error < 0) { + dev_err(&rspi->master->dev, "transmit timeout\n"); + return error; + } + rspi_write_data(rspi, data); + return 0; +} + +static int rspi_data_in(struct rspi_data *rspi) +{ + int error; + u8 data; + + error = rspi_wait_for_rx_full(rspi); + if (error < 0) { + dev_err(&rspi->master->dev, "receive timeout\n"); + return error; + } + data = rspi_read_data(rspi); + return data; +} + +static int rspi_pio_transfer(struct rspi_data *rspi, const u8 *tx, u8 *rx, + unsigned int n) +{ + while (n-- > 0) { + if (tx) { + int ret = rspi_data_out(rspi, *tx++); + if (ret < 0) + return ret; + } + if (rx) { + int ret = rspi_data_in(rspi); + if (ret < 0) + return ret; + *rx++ = ret; + } + } + + return 0; +} + +static void rspi_dma_complete(void *arg) +{ + struct rspi_data *rspi = arg; + + rspi->dma_callbacked = 1; + wake_up_interruptible(&rspi->wait); +} + +static int rspi_dma_transfer(struct rspi_data *rspi, struct sg_table *tx, + struct sg_table *rx) +{ + struct dma_async_tx_descriptor *desc_tx = NULL, *desc_rx = NULL; + u8 irq_mask = 0; + unsigned int other_irq = 0; + dma_cookie_t cookie; + int ret; + + /* First prepare and submit the DMA request(s), as this may fail */ + if (rx) { + desc_rx = dmaengine_prep_slave_sg(rspi->master->dma_rx, + rx->sgl, rx->nents, DMA_FROM_DEVICE, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + if (!desc_rx) { + ret = -EAGAIN; + goto no_dma_rx; + } + + desc_rx->callback = rspi_dma_complete; + desc_rx->callback_param = rspi; + cookie = dmaengine_submit(desc_rx); + if (dma_submit_error(cookie)) { + ret = cookie; + goto no_dma_rx; + } + + irq_mask |= SPCR_SPRIE; + } + + if (tx) { + desc_tx = dmaengine_prep_slave_sg(rspi->master->dma_tx, + tx->sgl, tx->nents, DMA_TO_DEVICE, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + if (!desc_tx) { + ret = -EAGAIN; + goto no_dma_tx; + } + + if (rx) { + /* No callback */ + desc_tx->callback = NULL; + } else { + desc_tx->callback = rspi_dma_complete; + desc_tx->callback_param = rspi; + } + cookie = dmaengine_submit(desc_tx); + if (dma_submit_error(cookie)) { + ret = cookie; + goto no_dma_tx; + } + + irq_mask |= SPCR_SPTIE; + } + + /* + * DMAC needs SPxIE, but if SPxIE is set, the IRQ routine will be + * called. So, this driver disables the IRQ while DMA transfer. + */ + if (tx) + disable_irq(other_irq = rspi->tx_irq); + if (rx && rspi->rx_irq != other_irq) + disable_irq(rspi->rx_irq); + + rspi_enable_irq(rspi, irq_mask); + rspi->dma_callbacked = 0; + + /* Now start DMA */ + if (rx) + dma_async_issue_pending(rspi->master->dma_rx); + if (tx) + dma_async_issue_pending(rspi->master->dma_tx); + + ret = wait_event_interruptible_timeout(rspi->wait, + rspi->dma_callbacked, HZ); + if (ret > 0 && rspi->dma_callbacked) + ret = 0; + else if (!ret) { + dev_err(&rspi->master->dev, "DMA timeout\n"); + ret = -ETIMEDOUT; + if (tx) + dmaengine_terminate_all(rspi->master->dma_tx); + if (rx) + dmaengine_terminate_all(rspi->master->dma_rx); + } + + rspi_disable_irq(rspi, irq_mask); + + if (tx) + enable_irq(rspi->tx_irq); + if (rx && rspi->rx_irq != other_irq) + enable_irq(rspi->rx_irq); + + return ret; + +no_dma_tx: + if (rx) + dmaengine_terminate_all(rspi->master->dma_rx); +no_dma_rx: + if (ret == -EAGAIN) { + pr_warn_once("%s %s: DMA not available, falling back to PIO\n", + dev_driver_string(&rspi->master->dev), + dev_name(&rspi->master->dev)); + } + return ret; +} + +static void rspi_receive_init(const struct rspi_data *rspi) +{ + u8 spsr; + + spsr = rspi_read8(rspi, RSPI_SPSR); + if (spsr & SPSR_SPRF) + rspi_read_data(rspi); /* dummy read */ + if (spsr & SPSR_OVRF) + rspi_write8(rspi, rspi_read8(rspi, RSPI_SPSR) & ~SPSR_OVRF, + RSPI_SPSR); +} + +static void rspi_rz_receive_init(const struct rspi_data *rspi) +{ + rspi_receive_init(rspi); + rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, RSPI_SPBFCR); + rspi_write8(rspi, 0, RSPI_SPBFCR); +} + +static void qspi_receive_init(const struct rspi_data *rspi) +{ + u8 spsr; + + spsr = rspi_read8(rspi, RSPI_SPSR); + if (spsr & SPSR_SPRF) + rspi_read_data(rspi); /* dummy read */ + rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, QSPI_SPBFCR); + rspi_write8(rspi, 0, QSPI_SPBFCR); +} + +static bool __rspi_can_dma(const struct rspi_data *rspi, + const struct spi_transfer *xfer) +{ + return xfer->len > rspi->ops->fifo_size; +} + +static bool rspi_can_dma(struct spi_master *master, struct spi_device *spi, + struct spi_transfer *xfer) +{ + struct rspi_data *rspi = spi_master_get_devdata(master); + + return __rspi_can_dma(rspi, xfer); +} + +static int rspi_dma_check_then_transfer(struct rspi_data *rspi, + struct spi_transfer *xfer) +{ + if (rspi->master->can_dma && __rspi_can_dma(rspi, xfer)) { + /* rx_buf can be NULL on RSPI on SH in TX-only Mode */ + int ret = rspi_dma_transfer(rspi, &xfer->tx_sg, + xfer->rx_buf ? &xfer->rx_sg : NULL); + if (ret != -EAGAIN) + return 0; + } + + return -EAGAIN; +} + +static int rspi_common_transfer(struct rspi_data *rspi, + struct spi_transfer *xfer) +{ + int ret; + + ret = rspi_dma_check_then_transfer(rspi, xfer); + if (ret != -EAGAIN) + return ret; + + ret = rspi_pio_transfer(rspi, xfer->tx_buf, xfer->rx_buf, xfer->len); + if (ret < 0) + return ret; + + /* Wait for the last transmission */ + rspi_wait_for_tx_empty(rspi); + + return 0; +} + +static int rspi_transfer_one(struct spi_master *master, struct spi_device *spi, + struct spi_transfer *xfer) +{ + struct rspi_data *rspi = spi_master_get_devdata(master); + u8 spcr; + + spcr = rspi_read8(rspi, RSPI_SPCR); + if (xfer->rx_buf) { + rspi_receive_init(rspi); + spcr &= ~SPCR_TXMD; + } else { + spcr |= SPCR_TXMD; + } + rspi_write8(rspi, spcr, RSPI_SPCR); + + return rspi_common_transfer(rspi, xfer); +} + +static int rspi_rz_transfer_one(struct spi_master *master, + struct spi_device *spi, + struct spi_transfer *xfer) +{ + struct rspi_data *rspi = spi_master_get_devdata(master); + + rspi_rz_receive_init(rspi); + + return rspi_common_transfer(rspi, xfer); +} + +static int qspi_trigger_transfer_out_int(struct rspi_data *rspi, const u8 *tx, + u8 *rx, unsigned int len) +{ + int i, n, ret; + int error; + + while (len > 0) { + n = qspi_set_send_trigger(rspi, len); + qspi_set_receive_trigger(rspi, len); + if (n == QSPI_BUFFER_SIZE) { + error = rspi_wait_for_tx_empty(rspi); + if (error < 0) { + dev_err(&rspi->master->dev, "transmit timeout\n"); + return error; + } + for (i = 0; i < n; i++) + rspi_write_data(rspi, *tx++); + + error = rspi_wait_for_rx_full(rspi); + if (error < 0) { + dev_err(&rspi->master->dev, "receive timeout\n"); + return error; + } + for (i = 0; i < n; i++) + *rx++ = rspi_read_data(rspi); + } else { + ret = rspi_pio_transfer(rspi, tx, rx, n); + if (ret < 0) + return ret; + } + len -= n; + } + + return 0; +} + +static int qspi_transfer_out_in(struct rspi_data *rspi, + struct spi_transfer *xfer) +{ + int ret; + + qspi_receive_init(rspi); + + ret = rspi_dma_check_then_transfer(rspi, xfer); + if (ret != -EAGAIN) + return ret; + + ret = qspi_trigger_transfer_out_int(rspi, xfer->tx_buf, + xfer->rx_buf, xfer->len); + if (ret < 0) + return ret; + + return 0; +} + +static int qspi_transfer_out(struct rspi_data *rspi, struct spi_transfer *xfer) +{ + int ret; + + if (rspi->master->can_dma && __rspi_can_dma(rspi, xfer)) { + ret = rspi_dma_transfer(rspi, &xfer->tx_sg, NULL); + if (ret != -EAGAIN) + return ret; + } + + ret = rspi_pio_transfer(rspi, xfer->tx_buf, NULL, xfer->len); + if (ret < 0) + return ret; + + /* Wait for the last transmission */ + rspi_wait_for_tx_empty(rspi); + + return 0; +} + +static int qspi_transfer_in(struct rspi_data *rspi, struct spi_transfer *xfer) +{ + if (rspi->master->can_dma && __rspi_can_dma(rspi, xfer)) { + int ret = rspi_dma_transfer(rspi, NULL, &xfer->rx_sg); + if (ret != -EAGAIN) + return ret; + } + + return rspi_pio_transfer(rspi, NULL, xfer->rx_buf, xfer->len); +} + +static int qspi_transfer_one(struct spi_master *master, struct spi_device *spi, + struct spi_transfer *xfer) +{ + struct rspi_data *rspi = spi_master_get_devdata(master); + + if (spi->mode & SPI_LOOP) { + return qspi_transfer_out_in(rspi, xfer); + } else if (xfer->tx_nbits > SPI_NBITS_SINGLE) { + /* Quad or Dual SPI Write */ + return qspi_transfer_out(rspi, xfer); + } else if (xfer->rx_nbits > SPI_NBITS_SINGLE) { + /* Quad or Dual SPI Read */ + return qspi_transfer_in(rspi, xfer); + } else { + /* Single SPI Transfer */ + return qspi_transfer_out_in(rspi, xfer); + } +} + +static int rspi_setup(struct spi_device *spi) +{ + struct rspi_data *rspi = spi_master_get_devdata(spi->master); + + rspi->max_speed_hz = spi->max_speed_hz; + + rspi->spcmd = SPCMD_SSLKP; + if (spi->mode & SPI_CPOL) + rspi->spcmd |= SPCMD_CPOL; + if (spi->mode & SPI_CPHA) + rspi->spcmd |= SPCMD_CPHA; + + /* CMOS output mode and MOSI signal from previous transfer */ + rspi->sppcr = 0; + if (spi->mode & SPI_LOOP) + rspi->sppcr |= SPPCR_SPLP; + + set_config_register(rspi, 8); + + return 0; +} + +static u16 qspi_transfer_mode(const struct spi_transfer *xfer) +{ + if (xfer->tx_buf) + switch (xfer->tx_nbits) { + case SPI_NBITS_QUAD: + return SPCMD_SPIMOD_QUAD; + case SPI_NBITS_DUAL: + return SPCMD_SPIMOD_DUAL; + default: + return 0; + } + if (xfer->rx_buf) + switch (xfer->rx_nbits) { + case SPI_NBITS_QUAD: + return SPCMD_SPIMOD_QUAD | SPCMD_SPRW; + case SPI_NBITS_DUAL: + return SPCMD_SPIMOD_DUAL | SPCMD_SPRW; + default: + return 0; + } + + return 0; +} + +static int qspi_setup_sequencer(struct rspi_data *rspi, + const struct spi_message *msg) +{ + const struct spi_transfer *xfer; + unsigned int i = 0, len = 0; + u16 current_mode = 0xffff, mode; + + list_for_each_entry(xfer, &msg->transfers, transfer_list) { + mode = qspi_transfer_mode(xfer); + if (mode == current_mode) { + len += xfer->len; + continue; + } + + /* Transfer mode change */ + if (i) { + /* Set transfer data length of previous transfer */ + rspi_write32(rspi, len, QSPI_SPBMUL(i - 1)); + } + + if (i >= QSPI_NUM_SPCMD) { + dev_err(&msg->spi->dev, + "Too many different transfer modes"); + return -EINVAL; + } + + /* Program transfer mode for this transfer */ + rspi_write16(rspi, rspi->spcmd | mode, RSPI_SPCMD(i)); + current_mode = mode; + len = xfer->len; + i++; + } + if (i) { + /* Set final transfer data length and sequence length */ + rspi_write32(rspi, len, QSPI_SPBMUL(i - 1)); + rspi_write8(rspi, i - 1, RSPI_SPSCR); + } + + return 0; +} + +static int rspi_prepare_message(struct spi_master *master, + struct spi_message *msg) +{ + struct rspi_data *rspi = spi_master_get_devdata(master); + int ret; + + if (msg->spi->mode & + (SPI_TX_DUAL | SPI_TX_QUAD | SPI_RX_DUAL | SPI_RX_QUAD)) { + /* Setup sequencer for messages with multiple transfer modes */ + ret = qspi_setup_sequencer(rspi, msg); + if (ret < 0) + return ret; + } + + /* Enable SPI function in master mode */ + rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | SPCR_SPE, RSPI_SPCR); + return 0; +} + +static int rspi_unprepare_message(struct spi_master *master, + struct spi_message *msg) +{ + struct rspi_data *rspi = spi_master_get_devdata(master); + + /* Disable SPI function */ + rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~SPCR_SPE, RSPI_SPCR); + + /* Reset sequencer for Single SPI Transfers */ + rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0); + rspi_write8(rspi, 0, RSPI_SPSCR); + return 0; +} + +static irqreturn_t rspi_irq_mux(int irq, void *_sr) +{ + struct rspi_data *rspi = _sr; + u8 spsr; + irqreturn_t ret = IRQ_NONE; + u8 disable_irq = 0; + + rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR); + if (spsr & SPSR_SPRF) + disable_irq |= SPCR_SPRIE; + if (spsr & SPSR_SPTEF) + disable_irq |= SPCR_SPTIE; + + if (disable_irq) { + ret = IRQ_HANDLED; + rspi_disable_irq(rspi, disable_irq); + wake_up(&rspi->wait); + } + + return ret; +} + +static irqreturn_t rspi_irq_rx(int irq, void *_sr) +{ + struct rspi_data *rspi = _sr; + u8 spsr; + + rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR); + if (spsr & SPSR_SPRF) { + rspi_disable_irq(rspi, SPCR_SPRIE); + wake_up(&rspi->wait); + return IRQ_HANDLED; + } + + return 0; +} + +static irqreturn_t rspi_irq_tx(int irq, void *_sr) +{ + struct rspi_data *rspi = _sr; + u8 spsr; + + rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR); + if (spsr & SPSR_SPTEF) { + rspi_disable_irq(rspi, SPCR_SPTIE); + wake_up(&rspi->wait); + return IRQ_HANDLED; + } + + return 0; +} + +static struct dma_chan *rspi_request_dma_chan(struct device *dev, + enum dma_transfer_direction dir, + unsigned int id, + dma_addr_t port_addr) +{ + dma_cap_mask_t mask; + struct dma_chan *chan; + struct dma_slave_config cfg; + int ret; + + dma_cap_zero(mask); + dma_cap_set(DMA_SLAVE, mask); + + chan = dma_request_slave_channel_compat(mask, shdma_chan_filter, + (void *)(unsigned long)id, dev, + dir == DMA_MEM_TO_DEV ? "tx" : "rx"); + if (!chan) { + dev_warn(dev, "dma_request_slave_channel_compat failed\n"); + return NULL; + } + + memset(&cfg, 0, sizeof(cfg)); + cfg.direction = dir; + if (dir == DMA_MEM_TO_DEV) { + cfg.dst_addr = port_addr; + cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; + } else { + cfg.src_addr = port_addr; + cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; + } + + ret = dmaengine_slave_config(chan, &cfg); + if (ret) { + dev_warn(dev, "dmaengine_slave_config failed %d\n", ret); + dma_release_channel(chan); + return NULL; + } + + return chan; +} + +static int rspi_request_dma(struct device *dev, struct spi_master *master, + const struct resource *res) +{ + const struct rspi_plat_data *rspi_pd = dev_get_platdata(dev); + unsigned int dma_tx_id, dma_rx_id; + + if (dev->of_node) { + /* In the OF case we will get the slave IDs from the DT */ + dma_tx_id = 0; + dma_rx_id = 0; + } else if (rspi_pd && rspi_pd->dma_tx_id && rspi_pd->dma_rx_id) { + dma_tx_id = rspi_pd->dma_tx_id; + dma_rx_id = rspi_pd->dma_rx_id; + } else { + /* The driver assumes no error. */ + return 0; + } + + master->dma_tx = rspi_request_dma_chan(dev, DMA_MEM_TO_DEV, dma_tx_id, + res->start + RSPI_SPDR); + if (!master->dma_tx) + return -ENODEV; + + master->dma_rx = rspi_request_dma_chan(dev, DMA_DEV_TO_MEM, dma_rx_id, + res->start + RSPI_SPDR); + if (!master->dma_rx) { + dma_release_channel(master->dma_tx); + master->dma_tx = NULL; + return -ENODEV; + } + + master->can_dma = rspi_can_dma; + dev_info(dev, "DMA available"); + return 0; +} + +static void rspi_release_dma(struct spi_master *master) +{ + if (master->dma_tx) + dma_release_channel(master->dma_tx); + if (master->dma_rx) + dma_release_channel(master->dma_rx); +} + +static int rspi_remove(struct platform_device *pdev) +{ + struct rspi_data *rspi = platform_get_drvdata(pdev); + + rspi_release_dma(rspi->master); + pm_runtime_disable(&pdev->dev); + + return 0; +} + +static const struct spi_ops rspi_ops = { + .set_config_register = rspi_set_config_register, + .transfer_one = rspi_transfer_one, + .mode_bits = SPI_CPHA | SPI_CPOL | SPI_LOOP, + .flags = SPI_MASTER_MUST_TX, + .fifo_size = 8, +}; + +static const struct spi_ops rspi_rz_ops = { + .set_config_register = rspi_rz_set_config_register, + .transfer_one = rspi_rz_transfer_one, + .mode_bits = SPI_CPHA | SPI_CPOL | SPI_LOOP, + .flags = SPI_MASTER_MUST_RX | SPI_MASTER_MUST_TX, + .fifo_size = 8, /* 8 for TX, 32 for RX */ +}; + +static const struct spi_ops qspi_ops = { + .set_config_register = qspi_set_config_register, + .transfer_one = qspi_transfer_one, + .mode_bits = SPI_CPHA | SPI_CPOL | SPI_LOOP | + SPI_TX_DUAL | SPI_TX_QUAD | + SPI_RX_DUAL | SPI_RX_QUAD, + .flags = SPI_MASTER_MUST_RX | SPI_MASTER_MUST_TX, + .fifo_size = 32, +}; + +#ifdef CONFIG_OF +static const struct of_device_id rspi_of_match[] = { + /* RSPI on legacy SH */ + { .compatible = "renesas,rspi", .data = &rspi_ops }, + /* RSPI on RZ/A1H */ + { .compatible = "renesas,rspi-rz", .data = &rspi_rz_ops }, + /* QSPI on R-Car Gen2 */ + { .compatible = "renesas,qspi", .data = &qspi_ops }, + { /* sentinel */ } +}; + +MODULE_DEVICE_TABLE(of, rspi_of_match); + +static int rspi_parse_dt(struct device *dev, struct spi_master *master) +{ + u32 num_cs; + int error; + + /* Parse DT properties */ + error = of_property_read_u32(dev->of_node, "num-cs", &num_cs); + if (error) { + dev_err(dev, "of_property_read_u32 num-cs failed %d\n", error); + return error; + } + + master->num_chipselect = num_cs; + return 0; +} +#else +#define rspi_of_match NULL +static inline int rspi_parse_dt(struct device *dev, struct spi_master *master) +{ + return -EINVAL; +} +#endif /* CONFIG_OF */ + +static int rspi_request_irq(struct device *dev, unsigned int irq, + irq_handler_t handler, const char *suffix, + void *dev_id) +{ + const char *name = devm_kasprintf(dev, GFP_KERNEL, "%s:%s", + dev_name(dev), suffix); + if (!name) + return -ENOMEM; + + return devm_request_irq(dev, irq, handler, 0, name, dev_id); +} + +static int rspi_probe(struct platform_device *pdev) +{ + struct resource *res; + struct spi_master *master; + struct rspi_data *rspi; + int ret; + const struct of_device_id *of_id; + const struct rspi_plat_data *rspi_pd; + const struct spi_ops *ops; + + master = spi_alloc_master(&pdev->dev, sizeof(struct rspi_data)); + if (master == NULL) { + dev_err(&pdev->dev, "spi_alloc_master error.\n"); + return -ENOMEM; + } + + of_id = of_match_device(rspi_of_match, &pdev->dev); + if (of_id) { + ops = of_id->data; + ret = rspi_parse_dt(&pdev->dev, master); + if (ret) + goto error1; + } else { + ops = (struct spi_ops *)pdev->id_entry->driver_data; + rspi_pd = dev_get_platdata(&pdev->dev); + if (rspi_pd && rspi_pd->num_chipselect) + master->num_chipselect = rspi_pd->num_chipselect; + else + master->num_chipselect = 2; /* default */ + } + + /* ops parameter check */ + if (!ops->set_config_register) { + dev_err(&pdev->dev, "there is no set_config_register\n"); + ret = -ENODEV; + goto error1; + } + + rspi = spi_master_get_devdata(master); + platform_set_drvdata(pdev, rspi); + rspi->ops = ops; + rspi->master = master; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + rspi->addr = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(rspi->addr)) { + ret = PTR_ERR(rspi->addr); + goto error1; + } + + rspi->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(rspi->clk)) { + dev_err(&pdev->dev, "cannot get clock\n"); + ret = PTR_ERR(rspi->clk); + goto error1; + } + + pm_runtime_enable(&pdev->dev); + + init_waitqueue_head(&rspi->wait); + + master->bus_num = pdev->id; + master->setup = rspi_setup; + master->auto_runtime_pm = true; + master->transfer_one = ops->transfer_one; + master->prepare_message = rspi_prepare_message; + master->unprepare_message = rspi_unprepare_message; + master->mode_bits = ops->mode_bits; + master->flags = ops->flags; + master->dev.of_node = pdev->dev.of_node; + + ret = platform_get_irq_byname(pdev, "rx"); + if (ret < 0) { + ret = platform_get_irq_byname(pdev, "mux"); + if (ret < 0) + ret = platform_get_irq(pdev, 0); + if (ret >= 0) + rspi->rx_irq = rspi->tx_irq = ret; + } else { + rspi->rx_irq = ret; + ret = platform_get_irq_byname(pdev, "tx"); + if (ret >= 0) + rspi->tx_irq = ret; + } + if (ret < 0) { + dev_err(&pdev->dev, "platform_get_irq error\n"); + goto error2; + } + + if (rspi->rx_irq == rspi->tx_irq) { + /* Single multiplexed interrupt */ + ret = rspi_request_irq(&pdev->dev, rspi->rx_irq, rspi_irq_mux, + "mux", rspi); + } else { + /* Multi-interrupt mode, only SPRI and SPTI are used */ + ret = rspi_request_irq(&pdev->dev, rspi->rx_irq, rspi_irq_rx, + "rx", rspi); + if (!ret) + ret = rspi_request_irq(&pdev->dev, rspi->tx_irq, + rspi_irq_tx, "tx", rspi); + } + if (ret < 0) { + dev_err(&pdev->dev, "request_irq error\n"); + goto error2; + } + + ret = rspi_request_dma(&pdev->dev, master, res); + if (ret < 0) + dev_warn(&pdev->dev, "DMA not available, using PIO\n"); + + ret = devm_spi_register_master(&pdev->dev, master); + if (ret < 0) { + dev_err(&pdev->dev, "spi_register_master error.\n"); + goto error3; + } + + dev_info(&pdev->dev, "probed\n"); + + return 0; + +error3: + rspi_release_dma(master); +error2: + pm_runtime_disable(&pdev->dev); +error1: + spi_master_put(master); + + return ret; +} + +static struct platform_device_id spi_driver_ids[] = { + { "rspi", (kernel_ulong_t)&rspi_ops }, + { "rspi-rz", (kernel_ulong_t)&rspi_rz_ops }, + { "qspi", (kernel_ulong_t)&qspi_ops }, + {}, +}; + +MODULE_DEVICE_TABLE(platform, spi_driver_ids); + +static struct platform_driver rspi_driver = { + .probe = rspi_probe, + .remove = rspi_remove, + .id_table = spi_driver_ids, + .driver = { + .name = "renesas_spi", + .of_match_table = of_match_ptr(rspi_of_match), + }, +}; +module_platform_driver(rspi_driver); + +MODULE_DESCRIPTION("Renesas RSPI bus driver"); +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR("Yoshihiro Shimoda"); +MODULE_ALIAS("platform:rspi"); diff --git a/drivers/spi/spi-s3c24xx-fiq.S b/drivers/spi/spi-s3c24xx-fiq.S new file mode 100644 index 000000000..059f2dc1f --- /dev/null +++ b/drivers/spi/spi-s3c24xx-fiq.S @@ -0,0 +1,116 @@ +/* linux/drivers/spi/spi_s3c24xx_fiq.S + * + * Copyright 2009 Simtec Electronics + * Ben Dooks <ben@simtec.co.uk> + * + * S3C24XX SPI - FIQ pseudo-DMA transfer code + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. +*/ + +#include <linux/linkage.h> +#include <asm/assembler.h> + +#include <mach/map.h> +#include <mach/regs-irq.h> +#include <plat/regs-spi.h> + +#include "spi-s3c24xx-fiq.h" + + .text + + @ entry to these routines is as follows, with the register names + @ defined in fiq.h so that they can be shared with the C files which + @ setup the calling registers. + @ + @ fiq_rirq The base of the IRQ registers to find S3C2410_SRCPND + @ fiq_rtmp Temporary register to hold tx/rx data + @ fiq_rspi The base of the SPI register block + @ fiq_rtx The tx buffer pointer + @ fiq_rrx The rx buffer pointer + @ fiq_rcount The number of bytes to move + + @ each entry starts with a word entry of how long it is + @ and an offset to the irq acknowledgment word + +ENTRY(s3c24xx_spi_fiq_rx) +s3c24xx_spi_fix_rx: + .word fiq_rx_end - fiq_rx_start + .word fiq_rx_irq_ack - fiq_rx_start +fiq_rx_start: + ldr fiq_rtmp, fiq_rx_irq_ack + str fiq_rtmp, [ fiq_rirq, # S3C2410_SRCPND - S3C24XX_VA_IRQ ] + + ldrb fiq_rtmp, [ fiq_rspi, # S3C2410_SPRDAT ] + strb fiq_rtmp, [ fiq_rrx ], #1 + + mov fiq_rtmp, #0xff + strb fiq_rtmp, [ fiq_rspi, # S3C2410_SPTDAT ] + + subs fiq_rcount, fiq_rcount, #1 + subnes pc, lr, #4 @@ return, still have work to do + + @@ set IRQ controller so that next op will trigger IRQ + mov fiq_rtmp, #0 + str fiq_rtmp, [ fiq_rirq, # S3C2410_INTMOD - S3C24XX_VA_IRQ ] + subs pc, lr, #4 + +fiq_rx_irq_ack: + .word 0 +fiq_rx_end: + +ENTRY(s3c24xx_spi_fiq_txrx) +s3c24xx_spi_fiq_txrx: + .word fiq_txrx_end - fiq_txrx_start + .word fiq_txrx_irq_ack - fiq_txrx_start +fiq_txrx_start: + + ldrb fiq_rtmp, [ fiq_rspi, # S3C2410_SPRDAT ] + strb fiq_rtmp, [ fiq_rrx ], #1 + + ldr fiq_rtmp, fiq_txrx_irq_ack + str fiq_rtmp, [ fiq_rirq, # S3C2410_SRCPND - S3C24XX_VA_IRQ ] + + ldrb fiq_rtmp, [ fiq_rtx ], #1 + strb fiq_rtmp, [ fiq_rspi, # S3C2410_SPTDAT ] + + subs fiq_rcount, fiq_rcount, #1 + subnes pc, lr, #4 @@ return, still have work to do + + mov fiq_rtmp, #0 + str fiq_rtmp, [ fiq_rirq, # S3C2410_INTMOD - S3C24XX_VA_IRQ ] + subs pc, lr, #4 + +fiq_txrx_irq_ack: + .word 0 + +fiq_txrx_end: + +ENTRY(s3c24xx_spi_fiq_tx) +s3c24xx_spi_fix_tx: + .word fiq_tx_end - fiq_tx_start + .word fiq_tx_irq_ack - fiq_tx_start +fiq_tx_start: + ldrb fiq_rtmp, [ fiq_rspi, # S3C2410_SPRDAT ] + + ldr fiq_rtmp, fiq_tx_irq_ack + str fiq_rtmp, [ fiq_rirq, # S3C2410_SRCPND - S3C24XX_VA_IRQ ] + + ldrb fiq_rtmp, [ fiq_rtx ], #1 + strb fiq_rtmp, [ fiq_rspi, # S3C2410_SPTDAT ] + + subs fiq_rcount, fiq_rcount, #1 + subnes pc, lr, #4 @@ return, still have work to do + + mov fiq_rtmp, #0 + str fiq_rtmp, [ fiq_rirq, # S3C2410_INTMOD - S3C24XX_VA_IRQ ] + subs pc, lr, #4 + +fiq_tx_irq_ack: + .word 0 + +fiq_tx_end: + + .end diff --git a/drivers/spi/spi-s3c24xx-fiq.h b/drivers/spi/spi-s3c24xx-fiq.h new file mode 100644 index 000000000..a5950bb25 --- /dev/null +++ b/drivers/spi/spi-s3c24xx-fiq.h @@ -0,0 +1,26 @@ +/* linux/drivers/spi/spi_s3c24xx_fiq.h + * + * Copyright 2009 Simtec Electronics + * Ben Dooks <ben@simtec.co.uk> + * + * S3C24XX SPI - FIQ pseudo-DMA transfer support + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. +*/ + +/* We have R8 through R13 to play with */ + +#ifdef __ASSEMBLY__ +#define __REG_NR(x) r##x +#else +#define __REG_NR(x) (x) +#endif + +#define fiq_rspi __REG_NR(8) +#define fiq_rtmp __REG_NR(9) +#define fiq_rrx __REG_NR(10) +#define fiq_rtx __REG_NR(11) +#define fiq_rcount __REG_NR(12) +#define fiq_rirq __REG_NR(13) diff --git a/drivers/spi/spi-s3c24xx.c b/drivers/spi/spi-s3c24xx.c new file mode 100644 index 000000000..f747ca269 --- /dev/null +++ b/drivers/spi/spi-s3c24xx.c @@ -0,0 +1,673 @@ +/* + * Copyright (c) 2006 Ben Dooks + * Copyright 2006-2009 Simtec Electronics + * Ben Dooks <ben@simtec.co.uk> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * +*/ + +#include <linux/spinlock.h> +#include <linux/interrupt.h> +#include <linux/delay.h> +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/clk.h> +#include <linux/platform_device.h> +#include <linux/gpio.h> +#include <linux/io.h> +#include <linux/slab.h> + +#include <linux/spi/spi.h> +#include <linux/spi/spi_bitbang.h> +#include <linux/spi/s3c24xx.h> +#include <linux/module.h> + +#include <plat/regs-spi.h> + +#include <asm/fiq.h> + +#include "spi-s3c24xx-fiq.h" + +/** + * s3c24xx_spi_devstate - per device data + * @hz: Last frequency calculated for @sppre field. + * @mode: Last mode setting for the @spcon field. + * @spcon: Value to write to the SPCON register. + * @sppre: Value to write to the SPPRE register. + */ +struct s3c24xx_spi_devstate { + unsigned int hz; + unsigned int mode; + u8 spcon; + u8 sppre; +}; + +enum spi_fiq_mode { + FIQ_MODE_NONE = 0, + FIQ_MODE_TX = 1, + FIQ_MODE_RX = 2, + FIQ_MODE_TXRX = 3, +}; + +struct s3c24xx_spi { + /* bitbang has to be first */ + struct spi_bitbang bitbang; + struct completion done; + + void __iomem *regs; + int irq; + int len; + int count; + + struct fiq_handler fiq_handler; + enum spi_fiq_mode fiq_mode; + unsigned char fiq_inuse; + unsigned char fiq_claimed; + + void (*set_cs)(struct s3c2410_spi_info *spi, + int cs, int pol); + + /* data buffers */ + const unsigned char *tx; + unsigned char *rx; + + struct clk *clk; + struct spi_master *master; + struct spi_device *curdev; + struct device *dev; + struct s3c2410_spi_info *pdata; +}; + +#define SPCON_DEFAULT (S3C2410_SPCON_MSTR | S3C2410_SPCON_SMOD_INT) +#define SPPIN_DEFAULT (S3C2410_SPPIN_KEEP) + +static inline struct s3c24xx_spi *to_hw(struct spi_device *sdev) +{ + return spi_master_get_devdata(sdev->master); +} + +static void s3c24xx_spi_gpiocs(struct s3c2410_spi_info *spi, int cs, int pol) +{ + gpio_set_value(spi->pin_cs, pol); +} + +static void s3c24xx_spi_chipsel(struct spi_device *spi, int value) +{ + struct s3c24xx_spi_devstate *cs = spi->controller_state; + struct s3c24xx_spi *hw = to_hw(spi); + unsigned int cspol = spi->mode & SPI_CS_HIGH ? 1 : 0; + + /* change the chipselect state and the state of the spi engine clock */ + + switch (value) { + case BITBANG_CS_INACTIVE: + hw->set_cs(hw->pdata, spi->chip_select, cspol^1); + writeb(cs->spcon, hw->regs + S3C2410_SPCON); + break; + + case BITBANG_CS_ACTIVE: + writeb(cs->spcon | S3C2410_SPCON_ENSCK, + hw->regs + S3C2410_SPCON); + hw->set_cs(hw->pdata, spi->chip_select, cspol); + break; + } +} + +static int s3c24xx_spi_update_state(struct spi_device *spi, + struct spi_transfer *t) +{ + struct s3c24xx_spi *hw = to_hw(spi); + struct s3c24xx_spi_devstate *cs = spi->controller_state; + unsigned int hz; + unsigned int div; + unsigned long clk; + + hz = t ? t->speed_hz : spi->max_speed_hz; + + if (!hz) + hz = spi->max_speed_hz; + + if (spi->mode != cs->mode) { + u8 spcon = SPCON_DEFAULT | S3C2410_SPCON_ENSCK; + + if (spi->mode & SPI_CPHA) + spcon |= S3C2410_SPCON_CPHA_FMTB; + + if (spi->mode & SPI_CPOL) + spcon |= S3C2410_SPCON_CPOL_HIGH; + + cs->mode = spi->mode; + cs->spcon = spcon; + } + + if (cs->hz != hz) { + clk = clk_get_rate(hw->clk); + div = DIV_ROUND_UP(clk, hz * 2) - 1; + + if (div > 255) + div = 255; + + dev_dbg(&spi->dev, "pre-scaler=%d (wanted %d, got %ld)\n", + div, hz, clk / (2 * (div + 1))); + + cs->hz = hz; + cs->sppre = div; + } + + return 0; +} + +static int s3c24xx_spi_setupxfer(struct spi_device *spi, + struct spi_transfer *t) +{ + struct s3c24xx_spi_devstate *cs = spi->controller_state; + struct s3c24xx_spi *hw = to_hw(spi); + int ret; + + ret = s3c24xx_spi_update_state(spi, t); + if (!ret) + writeb(cs->sppre, hw->regs + S3C2410_SPPRE); + + return ret; +} + +static int s3c24xx_spi_setup(struct spi_device *spi) +{ + struct s3c24xx_spi_devstate *cs = spi->controller_state; + struct s3c24xx_spi *hw = to_hw(spi); + int ret; + + /* allocate settings on the first call */ + if (!cs) { + cs = devm_kzalloc(&spi->dev, + sizeof(struct s3c24xx_spi_devstate), + GFP_KERNEL); + if (!cs) + return -ENOMEM; + + cs->spcon = SPCON_DEFAULT; + cs->hz = -1; + spi->controller_state = cs; + } + + /* initialise the state from the device */ + ret = s3c24xx_spi_update_state(spi, NULL); + if (ret) + return ret; + + spin_lock(&hw->bitbang.lock); + if (!hw->bitbang.busy) { + hw->bitbang.chipselect(spi, BITBANG_CS_INACTIVE); + /* need to ndelay for 0.5 clocktick ? */ + } + spin_unlock(&hw->bitbang.lock); + + return 0; +} + +static inline unsigned int hw_txbyte(struct s3c24xx_spi *hw, int count) +{ + return hw->tx ? hw->tx[count] : 0; +} + +#ifdef CONFIG_SPI_S3C24XX_FIQ +/* Support for FIQ based pseudo-DMA to improve the transfer speed. + * + * This code uses the assembly helper in spi_s3c24xx_spi.S which is + * used by the FIQ core to move data between main memory and the peripheral + * block. Since this is code running on the processor, there is no problem + * with cache coherency of the buffers, so we can use any buffer we like. + */ + +/** + * struct spi_fiq_code - FIQ code and header + * @length: The length of the code fragment, excluding this header. + * @ack_offset: The offset from @data to the word to place the IRQ ACK bit at. + * @data: The code itself to install as a FIQ handler. + */ +struct spi_fiq_code { + u32 length; + u32 ack_offset; + u8 data[0]; +}; + +extern struct spi_fiq_code s3c24xx_spi_fiq_txrx; +extern struct spi_fiq_code s3c24xx_spi_fiq_tx; +extern struct spi_fiq_code s3c24xx_spi_fiq_rx; + +/** + * ack_bit - turn IRQ into IRQ acknowledgement bit + * @irq: The interrupt number + * + * Returns the bit to write to the interrupt acknowledge register. + */ +static inline u32 ack_bit(unsigned int irq) +{ + return 1 << (irq - IRQ_EINT0); +} + +/** + * s3c24xx_spi_tryfiq - attempt to claim and setup FIQ for transfer + * @hw: The hardware state. + * + * Claim the FIQ handler (only one can be active at any one time) and + * then setup the correct transfer code for this transfer. + * + * This call updates all the necessary state information if successful, + * so the caller does not need to do anything more than start the transfer + * as normal, since the IRQ will have been re-routed to the FIQ handler. +*/ +static void s3c24xx_spi_tryfiq(struct s3c24xx_spi *hw) +{ + struct pt_regs regs; + enum spi_fiq_mode mode; + struct spi_fiq_code *code; + int ret; + + if (!hw->fiq_claimed) { + /* try and claim fiq if we haven't got it, and if not + * then return and simply use another transfer method */ + + ret = claim_fiq(&hw->fiq_handler); + if (ret) + return; + } + + if (hw->tx && !hw->rx) + mode = FIQ_MODE_TX; + else if (hw->rx && !hw->tx) + mode = FIQ_MODE_RX; + else + mode = FIQ_MODE_TXRX; + + regs.uregs[fiq_rspi] = (long)hw->regs; + regs.uregs[fiq_rrx] = (long)hw->rx; + regs.uregs[fiq_rtx] = (long)hw->tx + 1; + regs.uregs[fiq_rcount] = hw->len - 1; + regs.uregs[fiq_rirq] = (long)S3C24XX_VA_IRQ; + + set_fiq_regs(®s); + + if (hw->fiq_mode != mode) { + u32 *ack_ptr; + + hw->fiq_mode = mode; + + switch (mode) { + case FIQ_MODE_TX: + code = &s3c24xx_spi_fiq_tx; + break; + case FIQ_MODE_RX: + code = &s3c24xx_spi_fiq_rx; + break; + case FIQ_MODE_TXRX: + code = &s3c24xx_spi_fiq_txrx; + break; + default: + code = NULL; + } + + BUG_ON(!code); + + ack_ptr = (u32 *)&code->data[code->ack_offset]; + *ack_ptr = ack_bit(hw->irq); + + set_fiq_handler(&code->data, code->length); + } + + s3c24xx_set_fiq(hw->irq, true); + + hw->fiq_mode = mode; + hw->fiq_inuse = 1; +} + +/** + * s3c24xx_spi_fiqop - FIQ core code callback + * @pw: Data registered with the handler + * @release: Whether this is a release or a return. + * + * Called by the FIQ code when another module wants to use the FIQ, so + * return whether we are currently using this or not and then update our + * internal state. + */ +static int s3c24xx_spi_fiqop(void *pw, int release) +{ + struct s3c24xx_spi *hw = pw; + int ret = 0; + + if (release) { + if (hw->fiq_inuse) + ret = -EBUSY; + + /* note, we do not need to unroute the FIQ, as the FIQ + * vector code de-routes it to signal the end of transfer */ + + hw->fiq_mode = FIQ_MODE_NONE; + hw->fiq_claimed = 0; + } else { + hw->fiq_claimed = 1; + } + + return ret; +} + +/** + * s3c24xx_spi_initfiq - setup the information for the FIQ core + * @hw: The hardware state. + * + * Setup the fiq_handler block to pass to the FIQ core. + */ +static inline void s3c24xx_spi_initfiq(struct s3c24xx_spi *hw) +{ + hw->fiq_handler.dev_id = hw; + hw->fiq_handler.name = dev_name(hw->dev); + hw->fiq_handler.fiq_op = s3c24xx_spi_fiqop; +} + +/** + * s3c24xx_spi_usefiq - return if we should be using FIQ. + * @hw: The hardware state. + * + * Return true if the platform data specifies whether this channel is + * allowed to use the FIQ. + */ +static inline bool s3c24xx_spi_usefiq(struct s3c24xx_spi *hw) +{ + return hw->pdata->use_fiq; +} + +/** + * s3c24xx_spi_usingfiq - return if channel is using FIQ + * @spi: The hardware state. + * + * Return whether the channel is currently using the FIQ (separate from + * whether the FIQ is claimed). + */ +static inline bool s3c24xx_spi_usingfiq(struct s3c24xx_spi *spi) +{ + return spi->fiq_inuse; +} +#else + +static inline void s3c24xx_spi_initfiq(struct s3c24xx_spi *s) { } +static inline void s3c24xx_spi_tryfiq(struct s3c24xx_spi *s) { } +static inline bool s3c24xx_spi_usefiq(struct s3c24xx_spi *s) { return false; } +static inline bool s3c24xx_spi_usingfiq(struct s3c24xx_spi *s) { return false; } + +#endif /* CONFIG_SPI_S3C24XX_FIQ */ + +static int s3c24xx_spi_txrx(struct spi_device *spi, struct spi_transfer *t) +{ + struct s3c24xx_spi *hw = to_hw(spi); + + hw->tx = t->tx_buf; + hw->rx = t->rx_buf; + hw->len = t->len; + hw->count = 0; + + init_completion(&hw->done); + + hw->fiq_inuse = 0; + if (s3c24xx_spi_usefiq(hw) && t->len >= 3) + s3c24xx_spi_tryfiq(hw); + + /* send the first byte */ + writeb(hw_txbyte(hw, 0), hw->regs + S3C2410_SPTDAT); + + wait_for_completion(&hw->done); + return hw->count; +} + +static irqreturn_t s3c24xx_spi_irq(int irq, void *dev) +{ + struct s3c24xx_spi *hw = dev; + unsigned int spsta = readb(hw->regs + S3C2410_SPSTA); + unsigned int count = hw->count; + + if (spsta & S3C2410_SPSTA_DCOL) { + dev_dbg(hw->dev, "data-collision\n"); + complete(&hw->done); + goto irq_done; + } + + if (!(spsta & S3C2410_SPSTA_READY)) { + dev_dbg(hw->dev, "spi not ready for tx?\n"); + complete(&hw->done); + goto irq_done; + } + + if (!s3c24xx_spi_usingfiq(hw)) { + hw->count++; + + if (hw->rx) + hw->rx[count] = readb(hw->regs + S3C2410_SPRDAT); + + count++; + + if (count < hw->len) + writeb(hw_txbyte(hw, count), hw->regs + S3C2410_SPTDAT); + else + complete(&hw->done); + } else { + hw->count = hw->len; + hw->fiq_inuse = 0; + + if (hw->rx) + hw->rx[hw->len-1] = readb(hw->regs + S3C2410_SPRDAT); + + complete(&hw->done); + } + + irq_done: + return IRQ_HANDLED; +} + +static void s3c24xx_spi_initialsetup(struct s3c24xx_spi *hw) +{ + /* for the moment, permanently enable the clock */ + + clk_enable(hw->clk); + + /* program defaults into the registers */ + + writeb(0xff, hw->regs + S3C2410_SPPRE); + writeb(SPPIN_DEFAULT, hw->regs + S3C2410_SPPIN); + writeb(SPCON_DEFAULT, hw->regs + S3C2410_SPCON); + + if (hw->pdata) { + if (hw->set_cs == s3c24xx_spi_gpiocs) + gpio_direction_output(hw->pdata->pin_cs, 1); + + if (hw->pdata->gpio_setup) + hw->pdata->gpio_setup(hw->pdata, 1); + } +} + +static int s3c24xx_spi_probe(struct platform_device *pdev) +{ + struct s3c2410_spi_info *pdata; + struct s3c24xx_spi *hw; + struct spi_master *master; + struct resource *res; + int err = 0; + + master = spi_alloc_master(&pdev->dev, sizeof(struct s3c24xx_spi)); + if (master == NULL) { + dev_err(&pdev->dev, "No memory for spi_master\n"); + return -ENOMEM; + } + + hw = spi_master_get_devdata(master); + memset(hw, 0, sizeof(struct s3c24xx_spi)); + + hw->master = master; + hw->pdata = pdata = dev_get_platdata(&pdev->dev); + hw->dev = &pdev->dev; + + if (pdata == NULL) { + dev_err(&pdev->dev, "No platform data supplied\n"); + err = -ENOENT; + goto err_no_pdata; + } + + platform_set_drvdata(pdev, hw); + init_completion(&hw->done); + + /* initialise fiq handler */ + + s3c24xx_spi_initfiq(hw); + + /* setup the master state. */ + + /* the spi->mode bits understood by this driver: */ + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH; + + master->num_chipselect = hw->pdata->num_cs; + master->bus_num = pdata->bus_num; + master->bits_per_word_mask = SPI_BPW_MASK(8); + + /* setup the state for the bitbang driver */ + + hw->bitbang.master = hw->master; + hw->bitbang.setup_transfer = s3c24xx_spi_setupxfer; + hw->bitbang.chipselect = s3c24xx_spi_chipsel; + hw->bitbang.txrx_bufs = s3c24xx_spi_txrx; + + hw->master->setup = s3c24xx_spi_setup; + + dev_dbg(hw->dev, "bitbang at %p\n", &hw->bitbang); + + /* find and map our resources */ + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + hw->regs = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(hw->regs)) { + err = PTR_ERR(hw->regs); + goto err_no_pdata; + } + + hw->irq = platform_get_irq(pdev, 0); + if (hw->irq < 0) { + dev_err(&pdev->dev, "No IRQ specified\n"); + err = -ENOENT; + goto err_no_pdata; + } + + err = devm_request_irq(&pdev->dev, hw->irq, s3c24xx_spi_irq, 0, + pdev->name, hw); + if (err) { + dev_err(&pdev->dev, "Cannot claim IRQ\n"); + goto err_no_pdata; + } + + hw->clk = devm_clk_get(&pdev->dev, "spi"); + if (IS_ERR(hw->clk)) { + dev_err(&pdev->dev, "No clock for device\n"); + err = PTR_ERR(hw->clk); + goto err_no_pdata; + } + + /* setup any gpio we can */ + + if (!pdata->set_cs) { + if (pdata->pin_cs < 0) { + dev_err(&pdev->dev, "No chipselect pin\n"); + err = -EINVAL; + goto err_register; + } + + err = devm_gpio_request(&pdev->dev, pdata->pin_cs, + dev_name(&pdev->dev)); + if (err) { + dev_err(&pdev->dev, "Failed to get gpio for cs\n"); + goto err_register; + } + + hw->set_cs = s3c24xx_spi_gpiocs; + gpio_direction_output(pdata->pin_cs, 1); + } else + hw->set_cs = pdata->set_cs; + + s3c24xx_spi_initialsetup(hw); + + /* register our spi controller */ + + err = spi_bitbang_start(&hw->bitbang); + if (err) { + dev_err(&pdev->dev, "Failed to register SPI master\n"); + goto err_register; + } + + return 0; + + err_register: + clk_disable(hw->clk); + + err_no_pdata: + spi_master_put(hw->master); + return err; +} + +static int s3c24xx_spi_remove(struct platform_device *dev) +{ + struct s3c24xx_spi *hw = platform_get_drvdata(dev); + + spi_bitbang_stop(&hw->bitbang); + clk_disable(hw->clk); + spi_master_put(hw->master); + return 0; +} + + +#ifdef CONFIG_PM + +static int s3c24xx_spi_suspend(struct device *dev) +{ + struct s3c24xx_spi *hw = dev_get_drvdata(dev); + int ret; + + ret = spi_master_suspend(hw->master); + if (ret) + return ret; + + if (hw->pdata && hw->pdata->gpio_setup) + hw->pdata->gpio_setup(hw->pdata, 0); + + clk_disable(hw->clk); + return 0; +} + +static int s3c24xx_spi_resume(struct device *dev) +{ + struct s3c24xx_spi *hw = dev_get_drvdata(dev); + + s3c24xx_spi_initialsetup(hw); + return spi_master_resume(hw->master); +} + +static const struct dev_pm_ops s3c24xx_spi_pmops = { + .suspend = s3c24xx_spi_suspend, + .resume = s3c24xx_spi_resume, +}; + +#define S3C24XX_SPI_PMOPS &s3c24xx_spi_pmops +#else +#define S3C24XX_SPI_PMOPS NULL +#endif /* CONFIG_PM */ + +MODULE_ALIAS("platform:s3c2410-spi"); +static struct platform_driver s3c24xx_spi_driver = { + .probe = s3c24xx_spi_probe, + .remove = s3c24xx_spi_remove, + .driver = { + .name = "s3c2410-spi", + .pm = S3C24XX_SPI_PMOPS, + }, +}; +module_platform_driver(s3c24xx_spi_driver); + +MODULE_DESCRIPTION("S3C24XX SPI Driver"); +MODULE_AUTHOR("Ben Dooks, <ben@simtec.co.uk>"); +MODULE_LICENSE("GPL"); diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c new file mode 100644 index 000000000..b1c6731fb --- /dev/null +++ b/drivers/spi/spi-s3c64xx.c @@ -0,0 +1,1406 @@ +/* + * Copyright (C) 2009 Samsung Electronics Ltd. + * Jaswinder Singh <jassi.brar@samsung.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/init.h> +#include <linux/module.h> +#include <linux/interrupt.h> +#include <linux/delay.h> +#include <linux/clk.h> +#include <linux/dma-mapping.h> +#include <linux/dmaengine.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/spi/spi.h> +#include <linux/gpio.h> +#include <linux/of.h> +#include <linux/of_gpio.h> + +#include <linux/platform_data/spi-s3c64xx.h> + +#define MAX_SPI_PORTS 6 +#define S3C64XX_SPI_QUIRK_POLL (1 << 0) +#define S3C64XX_SPI_QUIRK_CS_AUTO (1 << 1) + +/* Registers and bit-fields */ + +#define S3C64XX_SPI_CH_CFG 0x00 +#define S3C64XX_SPI_CLK_CFG 0x04 +#define S3C64XX_SPI_MODE_CFG 0x08 +#define S3C64XX_SPI_SLAVE_SEL 0x0C +#define S3C64XX_SPI_INT_EN 0x10 +#define S3C64XX_SPI_STATUS 0x14 +#define S3C64XX_SPI_TX_DATA 0x18 +#define S3C64XX_SPI_RX_DATA 0x1C +#define S3C64XX_SPI_PACKET_CNT 0x20 +#define S3C64XX_SPI_PENDING_CLR 0x24 +#define S3C64XX_SPI_SWAP_CFG 0x28 +#define S3C64XX_SPI_FB_CLK 0x2C + +#define S3C64XX_SPI_CH_HS_EN (1<<6) /* High Speed Enable */ +#define S3C64XX_SPI_CH_SW_RST (1<<5) +#define S3C64XX_SPI_CH_SLAVE (1<<4) +#define S3C64XX_SPI_CPOL_L (1<<3) +#define S3C64XX_SPI_CPHA_B (1<<2) +#define S3C64XX_SPI_CH_RXCH_ON (1<<1) +#define S3C64XX_SPI_CH_TXCH_ON (1<<0) + +#define S3C64XX_SPI_CLKSEL_SRCMSK (3<<9) +#define S3C64XX_SPI_CLKSEL_SRCSHFT 9 +#define S3C64XX_SPI_ENCLK_ENABLE (1<<8) +#define S3C64XX_SPI_PSR_MASK 0xff + +#define S3C64XX_SPI_MODE_CH_TSZ_BYTE (0<<29) +#define S3C64XX_SPI_MODE_CH_TSZ_HALFWORD (1<<29) +#define S3C64XX_SPI_MODE_CH_TSZ_WORD (2<<29) +#define S3C64XX_SPI_MODE_CH_TSZ_MASK (3<<29) +#define S3C64XX_SPI_MODE_BUS_TSZ_BYTE (0<<17) +#define S3C64XX_SPI_MODE_BUS_TSZ_HALFWORD (1<<17) +#define S3C64XX_SPI_MODE_BUS_TSZ_WORD (2<<17) +#define S3C64XX_SPI_MODE_BUS_TSZ_MASK (3<<17) +#define S3C64XX_SPI_MODE_RXDMA_ON (1<<2) +#define S3C64XX_SPI_MODE_TXDMA_ON (1<<1) +#define S3C64XX_SPI_MODE_4BURST (1<<0) + +#define S3C64XX_SPI_SLAVE_AUTO (1<<1) +#define S3C64XX_SPI_SLAVE_SIG_INACT (1<<0) +#define S3C64XX_SPI_SLAVE_NSC_CNT_2 (2<<4) + +#define S3C64XX_SPI_INT_TRAILING_EN (1<<6) +#define S3C64XX_SPI_INT_RX_OVERRUN_EN (1<<5) +#define S3C64XX_SPI_INT_RX_UNDERRUN_EN (1<<4) +#define S3C64XX_SPI_INT_TX_OVERRUN_EN (1<<3) +#define S3C64XX_SPI_INT_TX_UNDERRUN_EN (1<<2) +#define S3C64XX_SPI_INT_RX_FIFORDY_EN (1<<1) +#define S3C64XX_SPI_INT_TX_FIFORDY_EN (1<<0) + +#define S3C64XX_SPI_ST_RX_OVERRUN_ERR (1<<5) +#define S3C64XX_SPI_ST_RX_UNDERRUN_ERR (1<<4) +#define S3C64XX_SPI_ST_TX_OVERRUN_ERR (1<<3) +#define S3C64XX_SPI_ST_TX_UNDERRUN_ERR (1<<2) +#define S3C64XX_SPI_ST_RX_FIFORDY (1<<1) +#define S3C64XX_SPI_ST_TX_FIFORDY (1<<0) + +#define S3C64XX_SPI_PACKET_CNT_EN (1<<16) + +#define S3C64XX_SPI_PND_TX_UNDERRUN_CLR (1<<4) +#define S3C64XX_SPI_PND_TX_OVERRUN_CLR (1<<3) +#define S3C64XX_SPI_PND_RX_UNDERRUN_CLR (1<<2) +#define S3C64XX_SPI_PND_RX_OVERRUN_CLR (1<<1) +#define S3C64XX_SPI_PND_TRAILING_CLR (1<<0) + +#define S3C64XX_SPI_SWAP_RX_HALF_WORD (1<<7) +#define S3C64XX_SPI_SWAP_RX_BYTE (1<<6) +#define S3C64XX_SPI_SWAP_RX_BIT (1<<5) +#define S3C64XX_SPI_SWAP_RX_EN (1<<4) +#define S3C64XX_SPI_SWAP_TX_HALF_WORD (1<<3) +#define S3C64XX_SPI_SWAP_TX_BYTE (1<<2) +#define S3C64XX_SPI_SWAP_TX_BIT (1<<1) +#define S3C64XX_SPI_SWAP_TX_EN (1<<0) + +#define S3C64XX_SPI_FBCLK_MSK (3<<0) + +#define FIFO_LVL_MASK(i) ((i)->port_conf->fifo_lvl_mask[i->port_id]) +#define S3C64XX_SPI_ST_TX_DONE(v, i) (((v) & \ + (1 << (i)->port_conf->tx_st_done)) ? 1 : 0) +#define TX_FIFO_LVL(v, i) (((v) >> 6) & FIFO_LVL_MASK(i)) +#define RX_FIFO_LVL(v, i) (((v) >> (i)->port_conf->rx_lvl_offset) & \ + FIFO_LVL_MASK(i)) + +#define S3C64XX_SPI_MAX_TRAILCNT 0x3ff +#define S3C64XX_SPI_TRAILCNT_OFF 19 + +#define S3C64XX_SPI_TRAILCNT S3C64XX_SPI_MAX_TRAILCNT + +#define msecs_to_loops(t) (loops_per_jiffy / 1000 * HZ * t) +#define is_polling(x) (x->port_conf->quirks & S3C64XX_SPI_QUIRK_POLL) + +#define RXBUSY (1<<2) +#define TXBUSY (1<<3) + +struct s3c64xx_spi_dma_data { + struct dma_chan *ch; + enum dma_transfer_direction direction; + unsigned int dmach; +}; + +/** + * struct s3c64xx_spi_info - SPI Controller hardware info + * @fifo_lvl_mask: Bit-mask for {TX|RX}_FIFO_LVL bits in SPI_STATUS register. + * @rx_lvl_offset: Bit offset of RX_FIFO_LVL bits in SPI_STATUS regiter. + * @tx_st_done: Bit offset of TX_DONE bit in SPI_STATUS regiter. + * @high_speed: True, if the controller supports HIGH_SPEED_EN bit. + * @clk_from_cmu: True, if the controller does not include a clock mux and + * prescaler unit. + * + * The Samsung s3c64xx SPI controller are used on various Samsung SoC's but + * differ in some aspects such as the size of the fifo and spi bus clock + * setup. Such differences are specified to the driver using this structure + * which is provided as driver data to the driver. + */ +struct s3c64xx_spi_port_config { + int fifo_lvl_mask[MAX_SPI_PORTS]; + int rx_lvl_offset; + int tx_st_done; + int quirks; + bool high_speed; + bool clk_from_cmu; +}; + +/** + * struct s3c64xx_spi_driver_data - Runtime info holder for SPI driver. + * @clk: Pointer to the spi clock. + * @src_clk: Pointer to the clock used to generate SPI signals. + * @master: Pointer to the SPI Protocol master. + * @cntrlr_info: Platform specific data for the controller this driver manages. + * @tgl_spi: Pointer to the last CS left untoggled by the cs_change hint. + * @lock: Controller specific lock. + * @state: Set of FLAGS to indicate status. + * @rx_dmach: Controller's DMA channel for Rx. + * @tx_dmach: Controller's DMA channel for Tx. + * @sfr_start: BUS address of SPI controller regs. + * @regs: Pointer to ioremap'ed controller registers. + * @irq: interrupt + * @xfer_completion: To indicate completion of xfer task. + * @cur_mode: Stores the active configuration of the controller. + * @cur_bpw: Stores the active bits per word settings. + * @cur_speed: Stores the active xfer clock speed. + */ +struct s3c64xx_spi_driver_data { + void __iomem *regs; + struct clk *clk; + struct clk *src_clk; + struct platform_device *pdev; + struct spi_master *master; + struct s3c64xx_spi_info *cntrlr_info; + struct spi_device *tgl_spi; + spinlock_t lock; + unsigned long sfr_start; + struct completion xfer_completion; + unsigned state; + unsigned cur_mode, cur_bpw; + unsigned cur_speed; + struct s3c64xx_spi_dma_data rx_dma; + struct s3c64xx_spi_dma_data tx_dma; + struct s3c64xx_spi_port_config *port_conf; + unsigned int port_id; +}; + +static void flush_fifo(struct s3c64xx_spi_driver_data *sdd) +{ + void __iomem *regs = sdd->regs; + unsigned long loops; + u32 val; + + writel(0, regs + S3C64XX_SPI_PACKET_CNT); + + val = readl(regs + S3C64XX_SPI_CH_CFG); + val &= ~(S3C64XX_SPI_CH_RXCH_ON | S3C64XX_SPI_CH_TXCH_ON); + writel(val, regs + S3C64XX_SPI_CH_CFG); + + val = readl(regs + S3C64XX_SPI_CH_CFG); + val |= S3C64XX_SPI_CH_SW_RST; + val &= ~S3C64XX_SPI_CH_HS_EN; + writel(val, regs + S3C64XX_SPI_CH_CFG); + + /* Flush TxFIFO*/ + loops = msecs_to_loops(1); + do { + val = readl(regs + S3C64XX_SPI_STATUS); + } while (TX_FIFO_LVL(val, sdd) && loops--); + + if (loops == 0) + dev_warn(&sdd->pdev->dev, "Timed out flushing TX FIFO\n"); + + /* Flush RxFIFO*/ + loops = msecs_to_loops(1); + do { + val = readl(regs + S3C64XX_SPI_STATUS); + if (RX_FIFO_LVL(val, sdd)) + readl(regs + S3C64XX_SPI_RX_DATA); + else + break; + } while (loops--); + + if (loops == 0) + dev_warn(&sdd->pdev->dev, "Timed out flushing RX FIFO\n"); + + val = readl(regs + S3C64XX_SPI_CH_CFG); + val &= ~S3C64XX_SPI_CH_SW_RST; + writel(val, regs + S3C64XX_SPI_CH_CFG); + + val = readl(regs + S3C64XX_SPI_MODE_CFG); + val &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON); + writel(val, regs + S3C64XX_SPI_MODE_CFG); +} + +static void s3c64xx_spi_dmacb(void *data) +{ + struct s3c64xx_spi_driver_data *sdd; + struct s3c64xx_spi_dma_data *dma = data; + unsigned long flags; + + if (dma->direction == DMA_DEV_TO_MEM) + sdd = container_of(data, + struct s3c64xx_spi_driver_data, rx_dma); + else + sdd = container_of(data, + struct s3c64xx_spi_driver_data, tx_dma); + + spin_lock_irqsave(&sdd->lock, flags); + + if (dma->direction == DMA_DEV_TO_MEM) { + sdd->state &= ~RXBUSY; + if (!(sdd->state & TXBUSY)) + complete(&sdd->xfer_completion); + } else { + sdd->state &= ~TXBUSY; + if (!(sdd->state & RXBUSY)) + complete(&sdd->xfer_completion); + } + + spin_unlock_irqrestore(&sdd->lock, flags); +} + +static void prepare_dma(struct s3c64xx_spi_dma_data *dma, + struct sg_table *sgt) +{ + struct s3c64xx_spi_driver_data *sdd; + struct dma_slave_config config; + struct dma_async_tx_descriptor *desc; + + memset(&config, 0, sizeof(config)); + + if (dma->direction == DMA_DEV_TO_MEM) { + sdd = container_of((void *)dma, + struct s3c64xx_spi_driver_data, rx_dma); + config.direction = dma->direction; + config.src_addr = sdd->sfr_start + S3C64XX_SPI_RX_DATA; + config.src_addr_width = sdd->cur_bpw / 8; + config.src_maxburst = 1; + dmaengine_slave_config(dma->ch, &config); + } else { + sdd = container_of((void *)dma, + struct s3c64xx_spi_driver_data, tx_dma); + config.direction = dma->direction; + config.dst_addr = sdd->sfr_start + S3C64XX_SPI_TX_DATA; + config.dst_addr_width = sdd->cur_bpw / 8; + config.dst_maxburst = 1; + dmaengine_slave_config(dma->ch, &config); + } + + desc = dmaengine_prep_slave_sg(dma->ch, sgt->sgl, sgt->nents, + dma->direction, DMA_PREP_INTERRUPT); + + desc->callback = s3c64xx_spi_dmacb; + desc->callback_param = dma; + + dmaengine_submit(desc); + dma_async_issue_pending(dma->ch); +} + +static int s3c64xx_spi_prepare_transfer(struct spi_master *spi) +{ + struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(spi); + dma_filter_fn filter = sdd->cntrlr_info->filter; + struct device *dev = &sdd->pdev->dev; + dma_cap_mask_t mask; + int ret; + + if (!is_polling(sdd)) { + dma_cap_zero(mask); + dma_cap_set(DMA_SLAVE, mask); + + /* Acquire DMA channels */ + sdd->rx_dma.ch = dma_request_slave_channel_compat(mask, filter, + (void *)(long)sdd->rx_dma.dmach, dev, "rx"); + if (!sdd->rx_dma.ch) { + dev_err(dev, "Failed to get RX DMA channel\n"); + ret = -EBUSY; + goto out; + } + spi->dma_rx = sdd->rx_dma.ch; + + sdd->tx_dma.ch = dma_request_slave_channel_compat(mask, filter, + (void *)(long)sdd->tx_dma.dmach, dev, "tx"); + if (!sdd->tx_dma.ch) { + dev_err(dev, "Failed to get TX DMA channel\n"); + ret = -EBUSY; + goto out_rx; + } + spi->dma_tx = sdd->tx_dma.ch; + } + + return 0; + +out_rx: + dma_release_channel(sdd->rx_dma.ch); +out: + return ret; +} + +static int s3c64xx_spi_unprepare_transfer(struct spi_master *spi) +{ + struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(spi); + + /* Free DMA channels */ + if (!is_polling(sdd)) { + dma_release_channel(sdd->rx_dma.ch); + dma_release_channel(sdd->tx_dma.ch); + } + + return 0; +} + +static bool s3c64xx_spi_can_dma(struct spi_master *master, + struct spi_device *spi, + struct spi_transfer *xfer) +{ + struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master); + + return xfer->len > (FIFO_LVL_MASK(sdd) >> 1) + 1; +} + +static void enable_datapath(struct s3c64xx_spi_driver_data *sdd, + struct spi_device *spi, + struct spi_transfer *xfer, int dma_mode) +{ + void __iomem *regs = sdd->regs; + u32 modecfg, chcfg; + + modecfg = readl(regs + S3C64XX_SPI_MODE_CFG); + modecfg &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON); + + chcfg = readl(regs + S3C64XX_SPI_CH_CFG); + chcfg &= ~S3C64XX_SPI_CH_TXCH_ON; + + if (dma_mode) { + chcfg &= ~S3C64XX_SPI_CH_RXCH_ON; + } else { + /* Always shift in data in FIFO, even if xfer is Tx only, + * this helps setting PCKT_CNT value for generating clocks + * as exactly needed. + */ + chcfg |= S3C64XX_SPI_CH_RXCH_ON; + writel(((xfer->len * 8 / sdd->cur_bpw) & 0xffff) + | S3C64XX_SPI_PACKET_CNT_EN, + regs + S3C64XX_SPI_PACKET_CNT); + } + + if (xfer->tx_buf != NULL) { + sdd->state |= TXBUSY; + chcfg |= S3C64XX_SPI_CH_TXCH_ON; + if (dma_mode) { + modecfg |= S3C64XX_SPI_MODE_TXDMA_ON; + prepare_dma(&sdd->tx_dma, &xfer->tx_sg); + } else { + switch (sdd->cur_bpw) { + case 32: + iowrite32_rep(regs + S3C64XX_SPI_TX_DATA, + xfer->tx_buf, xfer->len / 4); + break; + case 16: + iowrite16_rep(regs + S3C64XX_SPI_TX_DATA, + xfer->tx_buf, xfer->len / 2); + break; + default: + iowrite8_rep(regs + S3C64XX_SPI_TX_DATA, + xfer->tx_buf, xfer->len); + break; + } + } + } + + if (xfer->rx_buf != NULL) { + sdd->state |= RXBUSY; + + if (sdd->port_conf->high_speed && sdd->cur_speed >= 30000000UL + && !(sdd->cur_mode & SPI_CPHA)) + chcfg |= S3C64XX_SPI_CH_HS_EN; + + if (dma_mode) { + modecfg |= S3C64XX_SPI_MODE_RXDMA_ON; + chcfg |= S3C64XX_SPI_CH_RXCH_ON; + writel(((xfer->len * 8 / sdd->cur_bpw) & 0xffff) + | S3C64XX_SPI_PACKET_CNT_EN, + regs + S3C64XX_SPI_PACKET_CNT); + prepare_dma(&sdd->rx_dma, &xfer->rx_sg); + } + } + + writel(modecfg, regs + S3C64XX_SPI_MODE_CFG); + writel(chcfg, regs + S3C64XX_SPI_CH_CFG); +} + +static u32 s3c64xx_spi_wait_for_timeout(struct s3c64xx_spi_driver_data *sdd, + int timeout_ms) +{ + void __iomem *regs = sdd->regs; + unsigned long val = 1; + u32 status; + + /* max fifo depth available */ + u32 max_fifo = (FIFO_LVL_MASK(sdd) >> 1) + 1; + + if (timeout_ms) + val = msecs_to_loops(timeout_ms); + + do { + status = readl(regs + S3C64XX_SPI_STATUS); + } while (RX_FIFO_LVL(status, sdd) < max_fifo && --val); + + /* return the actual received data length */ + return RX_FIFO_LVL(status, sdd); +} + +static int wait_for_dma(struct s3c64xx_spi_driver_data *sdd, + struct spi_transfer *xfer) +{ + void __iomem *regs = sdd->regs; + unsigned long val; + u32 status; + int ms; + + /* millisecs to xfer 'len' bytes @ 'cur_speed' */ + ms = xfer->len * 8 * 1000 / sdd->cur_speed; + ms += 10; /* some tolerance */ + + val = msecs_to_jiffies(ms) + 10; + val = wait_for_completion_timeout(&sdd->xfer_completion, val); + + /* + * If the previous xfer was completed within timeout, then + * proceed further else return -EIO. + * DmaTx returns after simply writing data in the FIFO, + * w/o waiting for real transmission on the bus to finish. + * DmaRx returns only after Dma read data from FIFO which + * needs bus transmission to finish, so we don't worry if + * Xfer involved Rx(with or without Tx). + */ + if (val && !xfer->rx_buf) { + val = msecs_to_loops(10); + status = readl(regs + S3C64XX_SPI_STATUS); + while ((TX_FIFO_LVL(status, sdd) + || !S3C64XX_SPI_ST_TX_DONE(status, sdd)) + && --val) { + cpu_relax(); + status = readl(regs + S3C64XX_SPI_STATUS); + } + + } + + /* If timed out while checking rx/tx status return error */ + if (!val) + return -EIO; + + return 0; +} + +static int wait_for_pio(struct s3c64xx_spi_driver_data *sdd, + struct spi_transfer *xfer) +{ + void __iomem *regs = sdd->regs; + unsigned long val; + u32 status; + int loops; + u32 cpy_len; + u8 *buf; + int ms; + + /* millisecs to xfer 'len' bytes @ 'cur_speed' */ + ms = xfer->len * 8 * 1000 / sdd->cur_speed; + ms += 10; /* some tolerance */ + + val = msecs_to_loops(ms); + do { + status = readl(regs + S3C64XX_SPI_STATUS); + } while (RX_FIFO_LVL(status, sdd) < xfer->len && --val); + + + /* If it was only Tx */ + if (!xfer->rx_buf) { + sdd->state &= ~TXBUSY; + return 0; + } + + /* + * If the receive length is bigger than the controller fifo + * size, calculate the loops and read the fifo as many times. + * loops = length / max fifo size (calculated by using the + * fifo mask). + * For any size less than the fifo size the below code is + * executed atleast once. + */ + loops = xfer->len / ((FIFO_LVL_MASK(sdd) >> 1) + 1); + buf = xfer->rx_buf; + do { + /* wait for data to be received in the fifo */ + cpy_len = s3c64xx_spi_wait_for_timeout(sdd, + (loops ? ms : 0)); + + switch (sdd->cur_bpw) { + case 32: + ioread32_rep(regs + S3C64XX_SPI_RX_DATA, + buf, cpy_len / 4); + break; + case 16: + ioread16_rep(regs + S3C64XX_SPI_RX_DATA, + buf, cpy_len / 2); + break; + default: + ioread8_rep(regs + S3C64XX_SPI_RX_DATA, + buf, cpy_len); + break; + } + + buf = buf + cpy_len; + } while (loops--); + sdd->state &= ~RXBUSY; + + return 0; +} + +static void s3c64xx_spi_config(struct s3c64xx_spi_driver_data *sdd) +{ + void __iomem *regs = sdd->regs; + u32 val; + + /* Disable Clock */ + if (sdd->port_conf->clk_from_cmu) { + clk_disable_unprepare(sdd->src_clk); + } else { + val = readl(regs + S3C64XX_SPI_CLK_CFG); + val &= ~S3C64XX_SPI_ENCLK_ENABLE; + writel(val, regs + S3C64XX_SPI_CLK_CFG); + } + + /* Set Polarity and Phase */ + val = readl(regs + S3C64XX_SPI_CH_CFG); + val &= ~(S3C64XX_SPI_CH_SLAVE | + S3C64XX_SPI_CPOL_L | + S3C64XX_SPI_CPHA_B); + + if (sdd->cur_mode & SPI_CPOL) + val |= S3C64XX_SPI_CPOL_L; + + if (sdd->cur_mode & SPI_CPHA) + val |= S3C64XX_SPI_CPHA_B; + + writel(val, regs + S3C64XX_SPI_CH_CFG); + + /* Set Channel & DMA Mode */ + val = readl(regs + S3C64XX_SPI_MODE_CFG); + val &= ~(S3C64XX_SPI_MODE_BUS_TSZ_MASK + | S3C64XX_SPI_MODE_CH_TSZ_MASK); + + switch (sdd->cur_bpw) { + case 32: + val |= S3C64XX_SPI_MODE_BUS_TSZ_WORD; + val |= S3C64XX_SPI_MODE_CH_TSZ_WORD; + break; + case 16: + val |= S3C64XX_SPI_MODE_BUS_TSZ_HALFWORD; + val |= S3C64XX_SPI_MODE_CH_TSZ_HALFWORD; + break; + default: + val |= S3C64XX_SPI_MODE_BUS_TSZ_BYTE; + val |= S3C64XX_SPI_MODE_CH_TSZ_BYTE; + break; + } + + writel(val, regs + S3C64XX_SPI_MODE_CFG); + + if (sdd->port_conf->clk_from_cmu) { + /* Configure Clock */ + /* There is half-multiplier before the SPI */ + clk_set_rate(sdd->src_clk, sdd->cur_speed * 2); + /* Enable Clock */ + clk_prepare_enable(sdd->src_clk); + } else { + /* Configure Clock */ + val = readl(regs + S3C64XX_SPI_CLK_CFG); + val &= ~S3C64XX_SPI_PSR_MASK; + val |= ((clk_get_rate(sdd->src_clk) / sdd->cur_speed / 2 - 1) + & S3C64XX_SPI_PSR_MASK); + writel(val, regs + S3C64XX_SPI_CLK_CFG); + + /* Enable Clock */ + val = readl(regs + S3C64XX_SPI_CLK_CFG); + val |= S3C64XX_SPI_ENCLK_ENABLE; + writel(val, regs + S3C64XX_SPI_CLK_CFG); + } +} + +#define XFER_DMAADDR_INVALID DMA_BIT_MASK(32) + +static int s3c64xx_spi_prepare_message(struct spi_master *master, + struct spi_message *msg) +{ + struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master); + struct spi_device *spi = msg->spi; + struct s3c64xx_spi_csinfo *cs = spi->controller_data; + + /* If Master's(controller) state differs from that needed by Slave */ + if (sdd->cur_speed != spi->max_speed_hz + || sdd->cur_mode != spi->mode + || sdd->cur_bpw != spi->bits_per_word) { + sdd->cur_bpw = spi->bits_per_word; + sdd->cur_speed = spi->max_speed_hz; + sdd->cur_mode = spi->mode; + s3c64xx_spi_config(sdd); + } + + /* Configure feedback delay */ + writel(cs->fb_delay & 0x3, sdd->regs + S3C64XX_SPI_FB_CLK); + + return 0; +} + +static int s3c64xx_spi_transfer_one(struct spi_master *master, + struct spi_device *spi, + struct spi_transfer *xfer) +{ + struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master); + int status; + u32 speed; + u8 bpw; + unsigned long flags; + int use_dma; + + reinit_completion(&sdd->xfer_completion); + + /* Only BPW and Speed may change across transfers */ + bpw = xfer->bits_per_word; + speed = xfer->speed_hz ? : spi->max_speed_hz; + + if (bpw != sdd->cur_bpw || speed != sdd->cur_speed) { + sdd->cur_bpw = bpw; + sdd->cur_speed = speed; + s3c64xx_spi_config(sdd); + } + + /* Polling method for xfers not bigger than FIFO capacity */ + use_dma = 0; + if (!is_polling(sdd) && + (sdd->rx_dma.ch && sdd->tx_dma.ch && + (xfer->len > ((FIFO_LVL_MASK(sdd) >> 1) + 1)))) + use_dma = 1; + + spin_lock_irqsave(&sdd->lock, flags); + + /* Pending only which is to be done */ + sdd->state &= ~RXBUSY; + sdd->state &= ~TXBUSY; + + enable_datapath(sdd, spi, xfer, use_dma); + + /* Start the signals */ + if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO)) + writel(0, sdd->regs + S3C64XX_SPI_SLAVE_SEL); + else + writel(readl(sdd->regs + S3C64XX_SPI_SLAVE_SEL) + | S3C64XX_SPI_SLAVE_AUTO | S3C64XX_SPI_SLAVE_NSC_CNT_2, + sdd->regs + S3C64XX_SPI_SLAVE_SEL); + + spin_unlock_irqrestore(&sdd->lock, flags); + + if (use_dma) + status = wait_for_dma(sdd, xfer); + else + status = wait_for_pio(sdd, xfer); + + if (status) { + dev_err(&spi->dev, "I/O Error: rx-%d tx-%d res:rx-%c tx-%c len-%d\n", + xfer->rx_buf ? 1 : 0, xfer->tx_buf ? 1 : 0, + (sdd->state & RXBUSY) ? 'f' : 'p', + (sdd->state & TXBUSY) ? 'f' : 'p', + xfer->len); + + if (use_dma) { + if (xfer->tx_buf != NULL + && (sdd->state & TXBUSY)) + dmaengine_terminate_all(sdd->tx_dma.ch); + if (xfer->rx_buf != NULL + && (sdd->state & RXBUSY)) + dmaengine_terminate_all(sdd->rx_dma.ch); + } + } else { + flush_fifo(sdd); + } + + return status; +} + +static struct s3c64xx_spi_csinfo *s3c64xx_get_slave_ctrldata( + struct spi_device *spi) +{ + struct s3c64xx_spi_csinfo *cs; + struct device_node *slave_np, *data_np = NULL; + u32 fb_delay = 0; + + slave_np = spi->dev.of_node; + if (!slave_np) { + dev_err(&spi->dev, "device node not found\n"); + return ERR_PTR(-EINVAL); + } + + data_np = of_get_child_by_name(slave_np, "controller-data"); + if (!data_np) { + dev_err(&spi->dev, "child node 'controller-data' not found\n"); + return ERR_PTR(-EINVAL); + } + + cs = kzalloc(sizeof(*cs), GFP_KERNEL); + if (!cs) { + of_node_put(data_np); + return ERR_PTR(-ENOMEM); + } + + of_property_read_u32(data_np, "samsung,spi-feedback-delay", &fb_delay); + cs->fb_delay = fb_delay; + of_node_put(data_np); + return cs; +} + +/* + * Here we only check the validity of requested configuration + * and save the configuration in a local data-structure. + * The controller is actually configured only just before we + * get a message to transfer. + */ +static int s3c64xx_spi_setup(struct spi_device *spi) +{ + struct s3c64xx_spi_csinfo *cs = spi->controller_data; + struct s3c64xx_spi_driver_data *sdd; + struct s3c64xx_spi_info *sci; + int err; + + sdd = spi_master_get_devdata(spi->master); + if (spi->dev.of_node) { + cs = s3c64xx_get_slave_ctrldata(spi); + spi->controller_data = cs; + } else if (cs) { + /* On non-DT platforms the SPI core will set spi->cs_gpio + * to -ENOENT. The GPIO pin used to drive the chip select + * is defined by using platform data so spi->cs_gpio value + * has to be override to have the proper GPIO pin number. + */ + spi->cs_gpio = cs->line; + } + + if (IS_ERR_OR_NULL(cs)) { + dev_err(&spi->dev, "No CS for SPI(%d)\n", spi->chip_select); + return -ENODEV; + } + + if (!spi_get_ctldata(spi)) { + if (gpio_is_valid(spi->cs_gpio)) { + err = gpio_request_one(spi->cs_gpio, GPIOF_OUT_INIT_HIGH, + dev_name(&spi->dev)); + if (err) { + dev_err(&spi->dev, + "Failed to get /CS gpio [%d]: %d\n", + spi->cs_gpio, err); + goto err_gpio_req; + } + } + + spi_set_ctldata(spi, cs); + } + + sci = sdd->cntrlr_info; + + pm_runtime_get_sync(&sdd->pdev->dev); + + /* Check if we can provide the requested rate */ + if (!sdd->port_conf->clk_from_cmu) { + u32 psr, speed; + + /* Max possible */ + speed = clk_get_rate(sdd->src_clk) / 2 / (0 + 1); + + if (spi->max_speed_hz > speed) + spi->max_speed_hz = speed; + + psr = clk_get_rate(sdd->src_clk) / 2 / spi->max_speed_hz - 1; + psr &= S3C64XX_SPI_PSR_MASK; + if (psr == S3C64XX_SPI_PSR_MASK) + psr--; + + speed = clk_get_rate(sdd->src_clk) / 2 / (psr + 1); + if (spi->max_speed_hz < speed) { + if (psr+1 < S3C64XX_SPI_PSR_MASK) { + psr++; + } else { + err = -EINVAL; + goto setup_exit; + } + } + + speed = clk_get_rate(sdd->src_clk) / 2 / (psr + 1); + if (spi->max_speed_hz >= speed) { + spi->max_speed_hz = speed; + } else { + dev_err(&spi->dev, "Can't set %dHz transfer speed\n", + spi->max_speed_hz); + err = -EINVAL; + goto setup_exit; + } + } + + pm_runtime_put(&sdd->pdev->dev); + if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO)) + writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + S3C64XX_SPI_SLAVE_SEL); + return 0; + +setup_exit: + pm_runtime_put(&sdd->pdev->dev); + /* setup() returns with device de-selected */ + if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO)) + writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + S3C64XX_SPI_SLAVE_SEL); + + if (gpio_is_valid(spi->cs_gpio)) + gpio_free(spi->cs_gpio); + spi_set_ctldata(spi, NULL); + +err_gpio_req: + if (spi->dev.of_node) + kfree(cs); + + return err; +} + +static void s3c64xx_spi_cleanup(struct spi_device *spi) +{ + struct s3c64xx_spi_csinfo *cs = spi_get_ctldata(spi); + + if (gpio_is_valid(spi->cs_gpio)) { + gpio_free(spi->cs_gpio); + if (spi->dev.of_node) + kfree(cs); + else { + /* On non-DT platforms, the SPI core sets + * spi->cs_gpio to -ENOENT and .setup() + * overrides it with the GPIO pin value + * passed using platform data. + */ + spi->cs_gpio = -ENOENT; + } + } + + spi_set_ctldata(spi, NULL); +} + +static irqreturn_t s3c64xx_spi_irq(int irq, void *data) +{ + struct s3c64xx_spi_driver_data *sdd = data; + struct spi_master *spi = sdd->master; + unsigned int val, clr = 0; + + val = readl(sdd->regs + S3C64XX_SPI_STATUS); + + if (val & S3C64XX_SPI_ST_RX_OVERRUN_ERR) { + clr = S3C64XX_SPI_PND_RX_OVERRUN_CLR; + dev_err(&spi->dev, "RX overrun\n"); + } + if (val & S3C64XX_SPI_ST_RX_UNDERRUN_ERR) { + clr |= S3C64XX_SPI_PND_RX_UNDERRUN_CLR; + dev_err(&spi->dev, "RX underrun\n"); + } + if (val & S3C64XX_SPI_ST_TX_OVERRUN_ERR) { + clr |= S3C64XX_SPI_PND_TX_OVERRUN_CLR; + dev_err(&spi->dev, "TX overrun\n"); + } + if (val & S3C64XX_SPI_ST_TX_UNDERRUN_ERR) { + clr |= S3C64XX_SPI_PND_TX_UNDERRUN_CLR; + dev_err(&spi->dev, "TX underrun\n"); + } + + /* Clear the pending irq by setting and then clearing it */ + writel(clr, sdd->regs + S3C64XX_SPI_PENDING_CLR); + writel(0, sdd->regs + S3C64XX_SPI_PENDING_CLR); + + return IRQ_HANDLED; +} + +static void s3c64xx_spi_hwinit(struct s3c64xx_spi_driver_data *sdd, int channel) +{ + struct s3c64xx_spi_info *sci = sdd->cntrlr_info; + void __iomem *regs = sdd->regs; + unsigned int val; + + sdd->cur_speed = 0; + + if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO)) + writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + S3C64XX_SPI_SLAVE_SEL); + + /* Disable Interrupts - we use Polling if not DMA mode */ + writel(0, regs + S3C64XX_SPI_INT_EN); + + if (!sdd->port_conf->clk_from_cmu) + writel(sci->src_clk_nr << S3C64XX_SPI_CLKSEL_SRCSHFT, + regs + S3C64XX_SPI_CLK_CFG); + writel(0, regs + S3C64XX_SPI_MODE_CFG); + writel(0, regs + S3C64XX_SPI_PACKET_CNT); + + /* Clear any irq pending bits, should set and clear the bits */ + val = S3C64XX_SPI_PND_RX_OVERRUN_CLR | + S3C64XX_SPI_PND_RX_UNDERRUN_CLR | + S3C64XX_SPI_PND_TX_OVERRUN_CLR | + S3C64XX_SPI_PND_TX_UNDERRUN_CLR; + writel(val, regs + S3C64XX_SPI_PENDING_CLR); + writel(0, regs + S3C64XX_SPI_PENDING_CLR); + + writel(0, regs + S3C64XX_SPI_SWAP_CFG); + + val = readl(regs + S3C64XX_SPI_MODE_CFG); + val &= ~S3C64XX_SPI_MODE_4BURST; + val &= ~(S3C64XX_SPI_MAX_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF); + val |= (S3C64XX_SPI_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF); + writel(val, regs + S3C64XX_SPI_MODE_CFG); + + flush_fifo(sdd); +} + +#ifdef CONFIG_OF +static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev) +{ + struct s3c64xx_spi_info *sci; + u32 temp; + + sci = devm_kzalloc(dev, sizeof(*sci), GFP_KERNEL); + if (!sci) + return ERR_PTR(-ENOMEM); + + if (of_property_read_u32(dev->of_node, "samsung,spi-src-clk", &temp)) { + dev_warn(dev, "spi bus clock parent not specified, using clock at index 0 as parent\n"); + sci->src_clk_nr = 0; + } else { + sci->src_clk_nr = temp; + } + + if (of_property_read_u32(dev->of_node, "num-cs", &temp)) { + dev_warn(dev, "number of chip select lines not specified, assuming 1 chip select line\n"); + sci->num_cs = 1; + } else { + sci->num_cs = temp; + } + + return sci; +} +#else +static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev) +{ + return dev_get_platdata(dev); +} +#endif + +static const struct of_device_id s3c64xx_spi_dt_match[]; + +static inline struct s3c64xx_spi_port_config *s3c64xx_spi_get_port_config( + struct platform_device *pdev) +{ +#ifdef CONFIG_OF + if (pdev->dev.of_node) { + const struct of_device_id *match; + match = of_match_node(s3c64xx_spi_dt_match, pdev->dev.of_node); + return (struct s3c64xx_spi_port_config *)match->data; + } +#endif + return (struct s3c64xx_spi_port_config *) + platform_get_device_id(pdev)->driver_data; +} + +static int s3c64xx_spi_probe(struct platform_device *pdev) +{ + struct resource *mem_res; + struct resource *res; + struct s3c64xx_spi_driver_data *sdd; + struct s3c64xx_spi_info *sci = dev_get_platdata(&pdev->dev); + struct spi_master *master; + int ret, irq; + char clk_name[16]; + + if (!sci && pdev->dev.of_node) { + sci = s3c64xx_spi_parse_dt(&pdev->dev); + if (IS_ERR(sci)) + return PTR_ERR(sci); + } + + if (!sci) { + dev_err(&pdev->dev, "platform_data missing!\n"); + return -ENODEV; + } + + mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (mem_res == NULL) { + dev_err(&pdev->dev, "Unable to get SPI MEM resource\n"); + return -ENXIO; + } + + irq = platform_get_irq(pdev, 0); + if (irq < 0) { + dev_warn(&pdev->dev, "Failed to get IRQ: %d\n", irq); + return irq; + } + + master = spi_alloc_master(&pdev->dev, + sizeof(struct s3c64xx_spi_driver_data)); + if (master == NULL) { + dev_err(&pdev->dev, "Unable to allocate SPI Master\n"); + return -ENOMEM; + } + + platform_set_drvdata(pdev, master); + + sdd = spi_master_get_devdata(master); + sdd->port_conf = s3c64xx_spi_get_port_config(pdev); + sdd->master = master; + sdd->cntrlr_info = sci; + sdd->pdev = pdev; + sdd->sfr_start = mem_res->start; + if (pdev->dev.of_node) { + ret = of_alias_get_id(pdev->dev.of_node, "spi"); + if (ret < 0) { + dev_err(&pdev->dev, "failed to get alias id, errno %d\n", + ret); + goto err0; + } + sdd->port_id = ret; + } else { + sdd->port_id = pdev->id; + } + + sdd->cur_bpw = 8; + + if (!sdd->pdev->dev.of_node) { + res = platform_get_resource(pdev, IORESOURCE_DMA, 0); + if (!res) { + dev_warn(&pdev->dev, "Unable to get SPI tx dma resource. Switching to poll mode\n"); + sdd->port_conf->quirks = S3C64XX_SPI_QUIRK_POLL; + } else + sdd->tx_dma.dmach = res->start; + + res = platform_get_resource(pdev, IORESOURCE_DMA, 1); + if (!res) { + dev_warn(&pdev->dev, "Unable to get SPI rx dma resource. Switching to poll mode\n"); + sdd->port_conf->quirks = S3C64XX_SPI_QUIRK_POLL; + } else + sdd->rx_dma.dmach = res->start; + } + + sdd->tx_dma.direction = DMA_MEM_TO_DEV; + sdd->rx_dma.direction = DMA_DEV_TO_MEM; + + master->dev.of_node = pdev->dev.of_node; + master->bus_num = sdd->port_id; + master->setup = s3c64xx_spi_setup; + master->cleanup = s3c64xx_spi_cleanup; + master->prepare_transfer_hardware = s3c64xx_spi_prepare_transfer; + master->prepare_message = s3c64xx_spi_prepare_message; + master->transfer_one = s3c64xx_spi_transfer_one; + master->unprepare_transfer_hardware = s3c64xx_spi_unprepare_transfer; + master->num_chipselect = sci->num_cs; + master->dma_alignment = 8; + master->bits_per_word_mask = SPI_BPW_MASK(32) | SPI_BPW_MASK(16) | + SPI_BPW_MASK(8); + /* the spi->mode bits understood by this driver: */ + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH; + master->auto_runtime_pm = true; + if (!is_polling(sdd)) + master->can_dma = s3c64xx_spi_can_dma; + + sdd->regs = devm_ioremap_resource(&pdev->dev, mem_res); + if (IS_ERR(sdd->regs)) { + ret = PTR_ERR(sdd->regs); + goto err0; + } + + if (sci->cfg_gpio && sci->cfg_gpio()) { + dev_err(&pdev->dev, "Unable to config gpio\n"); + ret = -EBUSY; + goto err0; + } + + /* Setup clocks */ + sdd->clk = devm_clk_get(&pdev->dev, "spi"); + if (IS_ERR(sdd->clk)) { + dev_err(&pdev->dev, "Unable to acquire clock 'spi'\n"); + ret = PTR_ERR(sdd->clk); + goto err0; + } + + if (clk_prepare_enable(sdd->clk)) { + dev_err(&pdev->dev, "Couldn't enable clock 'spi'\n"); + ret = -EBUSY; + goto err0; + } + + sprintf(clk_name, "spi_busclk%d", sci->src_clk_nr); + sdd->src_clk = devm_clk_get(&pdev->dev, clk_name); + if (IS_ERR(sdd->src_clk)) { + dev_err(&pdev->dev, + "Unable to acquire clock '%s'\n", clk_name); + ret = PTR_ERR(sdd->src_clk); + goto err2; + } + + if (clk_prepare_enable(sdd->src_clk)) { + dev_err(&pdev->dev, "Couldn't enable clock '%s'\n", clk_name); + ret = -EBUSY; + goto err2; + } + + /* Setup Deufult Mode */ + s3c64xx_spi_hwinit(sdd, sdd->port_id); + + spin_lock_init(&sdd->lock); + init_completion(&sdd->xfer_completion); + + ret = devm_request_irq(&pdev->dev, irq, s3c64xx_spi_irq, 0, + "spi-s3c64xx", sdd); + if (ret != 0) { + dev_err(&pdev->dev, "Failed to request IRQ %d: %d\n", + irq, ret); + goto err3; + } + + writel(S3C64XX_SPI_INT_RX_OVERRUN_EN | S3C64XX_SPI_INT_RX_UNDERRUN_EN | + S3C64XX_SPI_INT_TX_OVERRUN_EN | S3C64XX_SPI_INT_TX_UNDERRUN_EN, + sdd->regs + S3C64XX_SPI_INT_EN); + + pm_runtime_set_active(&pdev->dev); + pm_runtime_enable(&pdev->dev); + + ret = devm_spi_register_master(&pdev->dev, master); + if (ret != 0) { + dev_err(&pdev->dev, "cannot register SPI master: %d\n", ret); + goto err3; + } + + dev_dbg(&pdev->dev, "Samsung SoC SPI Driver loaded for Bus SPI-%d with %d Slaves attached\n", + sdd->port_id, master->num_chipselect); + dev_dbg(&pdev->dev, "\tIOmem=[%pR]\tDMA=[Rx-%d, Tx-%d]\n", + mem_res, + sdd->rx_dma.dmach, sdd->tx_dma.dmach); + + return 0; + +err3: + clk_disable_unprepare(sdd->src_clk); +err2: + clk_disable_unprepare(sdd->clk); +err0: + spi_master_put(master); + + return ret; +} + +static int s3c64xx_spi_remove(struct platform_device *pdev) +{ + struct spi_master *master = spi_master_get(platform_get_drvdata(pdev)); + struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master); + + pm_runtime_disable(&pdev->dev); + + writel(0, sdd->regs + S3C64XX_SPI_INT_EN); + + clk_disable_unprepare(sdd->src_clk); + + clk_disable_unprepare(sdd->clk); + + return 0; +} + +#ifdef CONFIG_PM_SLEEP +static int s3c64xx_spi_suspend(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master); + + int ret = spi_master_suspend(master); + if (ret) + return ret; + + if (!pm_runtime_suspended(dev)) { + clk_disable_unprepare(sdd->clk); + clk_disable_unprepare(sdd->src_clk); + } + + sdd->cur_speed = 0; /* Output Clock is stopped */ + + return 0; +} + +static int s3c64xx_spi_resume(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master); + struct s3c64xx_spi_info *sci = sdd->cntrlr_info; + + if (sci->cfg_gpio) + sci->cfg_gpio(); + + if (!pm_runtime_suspended(dev)) { + clk_prepare_enable(sdd->src_clk); + clk_prepare_enable(sdd->clk); + } + + s3c64xx_spi_hwinit(sdd, sdd->port_id); + + return spi_master_resume(master); +} +#endif /* CONFIG_PM_SLEEP */ + +#ifdef CONFIG_PM +static int s3c64xx_spi_runtime_suspend(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master); + + clk_disable_unprepare(sdd->clk); + clk_disable_unprepare(sdd->src_clk); + + return 0; +} + +static int s3c64xx_spi_runtime_resume(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master); + int ret; + + ret = clk_prepare_enable(sdd->src_clk); + if (ret != 0) + return ret; + + ret = clk_prepare_enable(sdd->clk); + if (ret != 0) { + clk_disable_unprepare(sdd->src_clk); + return ret; + } + + return 0; +} +#endif /* CONFIG_PM */ + +static const struct dev_pm_ops s3c64xx_spi_pm = { + SET_SYSTEM_SLEEP_PM_OPS(s3c64xx_spi_suspend, s3c64xx_spi_resume) + SET_RUNTIME_PM_OPS(s3c64xx_spi_runtime_suspend, + s3c64xx_spi_runtime_resume, NULL) +}; + +static struct s3c64xx_spi_port_config s3c2443_spi_port_config = { + .fifo_lvl_mask = { 0x7f }, + .rx_lvl_offset = 13, + .tx_st_done = 21, + .high_speed = true, +}; + +static struct s3c64xx_spi_port_config s3c6410_spi_port_config = { + .fifo_lvl_mask = { 0x7f, 0x7F }, + .rx_lvl_offset = 13, + .tx_st_done = 21, +}; + +static struct s3c64xx_spi_port_config s5pv210_spi_port_config = { + .fifo_lvl_mask = { 0x1ff, 0x7F }, + .rx_lvl_offset = 15, + .tx_st_done = 25, + .high_speed = true, +}; + +static struct s3c64xx_spi_port_config exynos4_spi_port_config = { + .fifo_lvl_mask = { 0x1ff, 0x7F, 0x7F }, + .rx_lvl_offset = 15, + .tx_st_done = 25, + .high_speed = true, + .clk_from_cmu = true, +}; + +static struct s3c64xx_spi_port_config exynos5440_spi_port_config = { + .fifo_lvl_mask = { 0x1ff }, + .rx_lvl_offset = 15, + .tx_st_done = 25, + .high_speed = true, + .clk_from_cmu = true, + .quirks = S3C64XX_SPI_QUIRK_POLL, +}; + +static struct s3c64xx_spi_port_config exynos7_spi_port_config = { + .fifo_lvl_mask = { 0x1ff, 0x7F, 0x7F, 0x7F, 0x7F, 0x1ff}, + .rx_lvl_offset = 15, + .tx_st_done = 25, + .high_speed = true, + .clk_from_cmu = true, + .quirks = S3C64XX_SPI_QUIRK_CS_AUTO, +}; + +static struct platform_device_id s3c64xx_spi_driver_ids[] = { + { + .name = "s3c2443-spi", + .driver_data = (kernel_ulong_t)&s3c2443_spi_port_config, + }, { + .name = "s3c6410-spi", + .driver_data = (kernel_ulong_t)&s3c6410_spi_port_config, + }, { + .name = "s5pv210-spi", + .driver_data = (kernel_ulong_t)&s5pv210_spi_port_config, + }, { + .name = "exynos4210-spi", + .driver_data = (kernel_ulong_t)&exynos4_spi_port_config, + }, + { }, +}; + +static const struct of_device_id s3c64xx_spi_dt_match[] = { + { .compatible = "samsung,s3c2443-spi", + .data = (void *)&s3c2443_spi_port_config, + }, + { .compatible = "samsung,s3c6410-spi", + .data = (void *)&s3c6410_spi_port_config, + }, + { .compatible = "samsung,s5pv210-spi", + .data = (void *)&s5pv210_spi_port_config, + }, + { .compatible = "samsung,exynos4210-spi", + .data = (void *)&exynos4_spi_port_config, + }, + { .compatible = "samsung,exynos5440-spi", + .data = (void *)&exynos5440_spi_port_config, + }, + { .compatible = "samsung,exynos7-spi", + .data = (void *)&exynos7_spi_port_config, + }, + { }, +}; +MODULE_DEVICE_TABLE(of, s3c64xx_spi_dt_match); + +static struct platform_driver s3c64xx_spi_driver = { + .driver = { + .name = "s3c64xx-spi", + .pm = &s3c64xx_spi_pm, + .of_match_table = of_match_ptr(s3c64xx_spi_dt_match), + }, + .probe = s3c64xx_spi_probe, + .remove = s3c64xx_spi_remove, + .id_table = s3c64xx_spi_driver_ids, +}; +MODULE_ALIAS("platform:s3c64xx-spi"); + +module_platform_driver(s3c64xx_spi_driver); + +MODULE_AUTHOR("Jaswinder Singh <jassi.brar@samsung.com>"); +MODULE_DESCRIPTION("S3C64XX SPI Controller Driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/spi/spi-sc18is602.c b/drivers/spi/spi-sc18is602.c new file mode 100644 index 000000000..36af4d48a --- /dev/null +++ b/drivers/spi/spi-sc18is602.c @@ -0,0 +1,329 @@ +/* + * NXP SC18IS602/603 SPI driver + * + * Copyright (C) Guenter Roeck <linux@roeck-us.net> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/kernel.h> +#include <linux/err.h> +#include <linux/module.h> +#include <linux/spi/spi.h> +#include <linux/i2c.h> +#include <linux/delay.h> +#include <linux/pm_runtime.h> +#include <linux/of.h> +#include <linux/platform_data/sc18is602.h> + +enum chips { sc18is602, sc18is602b, sc18is603 }; + +#define SC18IS602_BUFSIZ 200 +#define SC18IS602_CLOCK 7372000 + +#define SC18IS602_MODE_CPHA BIT(2) +#define SC18IS602_MODE_CPOL BIT(3) +#define SC18IS602_MODE_LSB_FIRST BIT(5) +#define SC18IS602_MODE_CLOCK_DIV_4 0x0 +#define SC18IS602_MODE_CLOCK_DIV_16 0x1 +#define SC18IS602_MODE_CLOCK_DIV_64 0x2 +#define SC18IS602_MODE_CLOCK_DIV_128 0x3 + +struct sc18is602 { + struct spi_master *master; + struct device *dev; + u8 ctrl; + u32 freq; + u32 speed; + + /* I2C data */ + struct i2c_client *client; + enum chips id; + u8 buffer[SC18IS602_BUFSIZ + 1]; + int tlen; /* Data queued for tx in buffer */ + int rindex; /* Receive data index in buffer */ +}; + +static int sc18is602_wait_ready(struct sc18is602 *hw, int len) +{ + int i, err; + int usecs = 1000000 * len / hw->speed + 1; + u8 dummy[1]; + + for (i = 0; i < 10; i++) { + err = i2c_master_recv(hw->client, dummy, 1); + if (err >= 0) + return 0; + usleep_range(usecs, usecs * 2); + } + return -ETIMEDOUT; +} + +static int sc18is602_txrx(struct sc18is602 *hw, struct spi_message *msg, + struct spi_transfer *t, bool do_transfer) +{ + unsigned int len = t->len; + int ret; + + if (hw->tlen == 0) { + /* First byte (I2C command) is chip select */ + hw->buffer[0] = 1 << msg->spi->chip_select; + hw->tlen = 1; + hw->rindex = 0; + } + /* + * We can not immediately send data to the chip, since each I2C message + * resembles a full SPI message (from CS active to CS inactive). + * Enqueue messages up to the first read or until do_transfer is true. + */ + if (t->tx_buf) { + memcpy(&hw->buffer[hw->tlen], t->tx_buf, len); + hw->tlen += len; + if (t->rx_buf) + do_transfer = true; + else + hw->rindex = hw->tlen - 1; + } else if (t->rx_buf) { + /* + * For receive-only transfers we still need to perform a dummy + * write to receive data from the SPI chip. + * Read data starts at the end of transmit data (minus 1 to + * account for CS). + */ + hw->rindex = hw->tlen - 1; + memset(&hw->buffer[hw->tlen], 0, len); + hw->tlen += len; + do_transfer = true; + } + + if (do_transfer && hw->tlen > 1) { + ret = sc18is602_wait_ready(hw, SC18IS602_BUFSIZ); + if (ret < 0) + return ret; + ret = i2c_master_send(hw->client, hw->buffer, hw->tlen); + if (ret < 0) + return ret; + if (ret != hw->tlen) + return -EIO; + + if (t->rx_buf) { + int rlen = hw->rindex + len; + + ret = sc18is602_wait_ready(hw, hw->tlen); + if (ret < 0) + return ret; + ret = i2c_master_recv(hw->client, hw->buffer, rlen); + if (ret < 0) + return ret; + if (ret != rlen) + return -EIO; + memcpy(t->rx_buf, &hw->buffer[hw->rindex], len); + } + hw->tlen = 0; + } + return len; +} + +static int sc18is602_setup_transfer(struct sc18is602 *hw, u32 hz, u8 mode) +{ + u8 ctrl = 0; + int ret; + + if (mode & SPI_CPHA) + ctrl |= SC18IS602_MODE_CPHA; + if (mode & SPI_CPOL) + ctrl |= SC18IS602_MODE_CPOL; + if (mode & SPI_LSB_FIRST) + ctrl |= SC18IS602_MODE_LSB_FIRST; + + /* Find the closest clock speed */ + if (hz >= hw->freq / 4) { + ctrl |= SC18IS602_MODE_CLOCK_DIV_4; + hw->speed = hw->freq / 4; + } else if (hz >= hw->freq / 16) { + ctrl |= SC18IS602_MODE_CLOCK_DIV_16; + hw->speed = hw->freq / 16; + } else if (hz >= hw->freq / 64) { + ctrl |= SC18IS602_MODE_CLOCK_DIV_64; + hw->speed = hw->freq / 64; + } else { + ctrl |= SC18IS602_MODE_CLOCK_DIV_128; + hw->speed = hw->freq / 128; + } + + /* + * Don't do anything if the control value did not change. The initial + * value of 0xff for hw->ctrl ensures that the correct mode will be set + * with the first call to this function. + */ + if (ctrl == hw->ctrl) + return 0; + + ret = i2c_smbus_write_byte_data(hw->client, 0xf0, ctrl); + if (ret < 0) + return ret; + + hw->ctrl = ctrl; + + return 0; +} + +static int sc18is602_check_transfer(struct spi_device *spi, + struct spi_transfer *t, int tlen) +{ + if (t && t->len + tlen > SC18IS602_BUFSIZ) + return -EINVAL; + + return 0; +} + +static int sc18is602_transfer_one(struct spi_master *master, + struct spi_message *m) +{ + struct sc18is602 *hw = spi_master_get_devdata(master); + struct spi_device *spi = m->spi; + struct spi_transfer *t; + int status = 0; + + hw->tlen = 0; + list_for_each_entry(t, &m->transfers, transfer_list) { + bool do_transfer; + + status = sc18is602_check_transfer(spi, t, hw->tlen); + if (status < 0) + break; + + status = sc18is602_setup_transfer(hw, t->speed_hz, spi->mode); + if (status < 0) + break; + + do_transfer = t->cs_change || list_is_last(&t->transfer_list, + &m->transfers); + + if (t->len) { + status = sc18is602_txrx(hw, m, t, do_transfer); + if (status < 0) + break; + m->actual_length += status; + } + status = 0; + + if (t->delay_usecs) + udelay(t->delay_usecs); + } + m->status = status; + spi_finalize_current_message(master); + + return status; +} + +static int sc18is602_setup(struct spi_device *spi) +{ + struct sc18is602 *hw = spi_master_get_devdata(spi->master); + + /* SC18IS602 does not support CS2 */ + if (hw->id == sc18is602 && spi->chip_select == 2) + return -ENXIO; + + return 0; +} + +static int sc18is602_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct device *dev = &client->dev; + struct device_node *np = dev->of_node; + struct sc18is602_platform_data *pdata = dev_get_platdata(dev); + struct sc18is602 *hw; + struct spi_master *master; + int error; + + if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C | + I2C_FUNC_SMBUS_WRITE_BYTE_DATA)) + return -EINVAL; + + master = spi_alloc_master(dev, sizeof(struct sc18is602)); + if (!master) + return -ENOMEM; + + hw = spi_master_get_devdata(master); + i2c_set_clientdata(client, hw); + + hw->master = master; + hw->client = client; + hw->dev = dev; + hw->ctrl = 0xff; + + hw->id = id->driver_data; + + switch (hw->id) { + case sc18is602: + case sc18is602b: + master->num_chipselect = 4; + hw->freq = SC18IS602_CLOCK; + break; + case sc18is603: + master->num_chipselect = 2; + if (pdata) { + hw->freq = pdata->clock_frequency; + } else { + const __be32 *val; + int len; + + val = of_get_property(np, "clock-frequency", &len); + if (val && len >= sizeof(__be32)) + hw->freq = be32_to_cpup(val); + } + if (!hw->freq) + hw->freq = SC18IS602_CLOCK; + break; + } + master->bus_num = np ? -1 : client->adapter->nr; + master->mode_bits = SPI_CPHA | SPI_CPOL | SPI_LSB_FIRST; + master->bits_per_word_mask = SPI_BPW_MASK(8); + master->setup = sc18is602_setup; + master->transfer_one_message = sc18is602_transfer_one; + master->dev.of_node = np; + master->min_speed_hz = hw->freq / 128; + master->max_speed_hz = hw->freq / 4; + + error = devm_spi_register_master(dev, master); + if (error) + goto error_reg; + + return 0; + +error_reg: + spi_master_put(master); + return error; +} + +static const struct i2c_device_id sc18is602_id[] = { + { "sc18is602", sc18is602 }, + { "sc18is602b", sc18is602b }, + { "sc18is603", sc18is603 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, sc18is602_id); + +static struct i2c_driver sc18is602_driver = { + .driver = { + .name = "sc18is602", + }, + .probe = sc18is602_probe, + .id_table = sc18is602_id, +}; + +module_i2c_driver(sc18is602_driver); + +MODULE_DESCRIPTION("SC18IC602/603 SPI Master Driver"); +MODULE_AUTHOR("Guenter Roeck"); +MODULE_LICENSE("GPL"); diff --git a/drivers/spi/spi-sh-hspi.c b/drivers/spi/spi-sh-hspi.c new file mode 100644 index 000000000..20e800e70 --- /dev/null +++ b/drivers/spi/spi-sh-hspi.c @@ -0,0 +1,321 @@ +/* + * SuperH HSPI bus driver + * + * Copyright (C) 2011 Kuninori Morimoto + * + * Based on spi-sh.c: + * Based on pxa2xx_spi.c: + * Copyright (C) 2011 Renesas Solutions Corp. + * Copyright (C) 2005 Stephen Street / StreetFire Sound Labs + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; version 2 of the License. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/clk.h> +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/timer.h> +#include <linux/delay.h> +#include <linux/list.h> +#include <linux/interrupt.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/io.h> +#include <linux/spi/spi.h> +#include <linux/spi/sh_hspi.h> + +#define SPCR 0x00 +#define SPSR 0x04 +#define SPSCR 0x08 +#define SPTBR 0x0C +#define SPRBR 0x10 +#define SPCR2 0x14 + +/* SPSR */ +#define RXFL (1 << 2) + +struct hspi_priv { + void __iomem *addr; + struct spi_master *master; + struct device *dev; + struct clk *clk; +}; + +/* + * basic function + */ +static void hspi_write(struct hspi_priv *hspi, int reg, u32 val) +{ + iowrite32(val, hspi->addr + reg); +} + +static u32 hspi_read(struct hspi_priv *hspi, int reg) +{ + return ioread32(hspi->addr + reg); +} + +static void hspi_bit_set(struct hspi_priv *hspi, int reg, u32 mask, u32 set) +{ + u32 val = hspi_read(hspi, reg); + + val &= ~mask; + val |= set & mask; + + hspi_write(hspi, reg, val); +} + +/* + * transfer function + */ +static int hspi_status_check_timeout(struct hspi_priv *hspi, u32 mask, u32 val) +{ + int t = 256; + + while (t--) { + if ((mask & hspi_read(hspi, SPSR)) == val) + return 0; + + udelay(10); + } + + dev_err(hspi->dev, "timeout\n"); + return -ETIMEDOUT; +} + +/* + * spi master function + */ + +#define hspi_hw_cs_enable(hspi) hspi_hw_cs_ctrl(hspi, 0) +#define hspi_hw_cs_disable(hspi) hspi_hw_cs_ctrl(hspi, 1) +static void hspi_hw_cs_ctrl(struct hspi_priv *hspi, int hi) +{ + hspi_bit_set(hspi, SPSCR, (1 << 6), (hi) << 6); +} + +static void hspi_hw_setup(struct hspi_priv *hspi, + struct spi_message *msg, + struct spi_transfer *t) +{ + struct spi_device *spi = msg->spi; + struct device *dev = hspi->dev; + u32 spcr, idiv_clk; + u32 rate, best_rate, min, tmp; + + /* + * find best IDIV/CLKCx settings + */ + min = ~0; + best_rate = 0; + spcr = 0; + for (idiv_clk = 0x00; idiv_clk <= 0x3F; idiv_clk++) { + rate = clk_get_rate(hspi->clk); + + /* IDIV calculation */ + if (idiv_clk & (1 << 5)) + rate /= 128; + else + rate /= 16; + + /* CLKCx calculation */ + rate /= (((idiv_clk & 0x1F) + 1) * 2); + + /* save best settings */ + tmp = abs(t->speed_hz - rate); + if (tmp < min) { + min = tmp; + spcr = idiv_clk; + best_rate = rate; + } + } + + if (spi->mode & SPI_CPHA) + spcr |= 1 << 7; + if (spi->mode & SPI_CPOL) + spcr |= 1 << 6; + + dev_dbg(dev, "speed %d/%d\n", t->speed_hz, best_rate); + + hspi_write(hspi, SPCR, spcr); + hspi_write(hspi, SPSR, 0x0); + hspi_write(hspi, SPSCR, 0x21); /* master mode / CS control */ +} + +static int hspi_transfer_one_message(struct spi_master *master, + struct spi_message *msg) +{ + struct hspi_priv *hspi = spi_master_get_devdata(master); + struct spi_transfer *t; + u32 tx; + u32 rx; + int ret, i; + unsigned int cs_change; + const int nsecs = 50; + + dev_dbg(hspi->dev, "%s\n", __func__); + + cs_change = 1; + ret = 0; + list_for_each_entry(t, &msg->transfers, transfer_list) { + + if (cs_change) { + hspi_hw_setup(hspi, msg, t); + hspi_hw_cs_enable(hspi); + ndelay(nsecs); + } + cs_change = t->cs_change; + + for (i = 0; i < t->len; i++) { + + /* wait remains */ + ret = hspi_status_check_timeout(hspi, 0x1, 0); + if (ret < 0) + break; + + tx = 0; + if (t->tx_buf) + tx = (u32)((u8 *)t->tx_buf)[i]; + + hspi_write(hspi, SPTBR, tx); + + /* wait receive */ + ret = hspi_status_check_timeout(hspi, 0x4, 0x4); + if (ret < 0) + break; + + rx = hspi_read(hspi, SPRBR); + if (t->rx_buf) + ((u8 *)t->rx_buf)[i] = (u8)rx; + + } + + msg->actual_length += t->len; + + if (t->delay_usecs) + udelay(t->delay_usecs); + + if (cs_change) { + ndelay(nsecs); + hspi_hw_cs_disable(hspi); + ndelay(nsecs); + } + } + + msg->status = ret; + if (!cs_change) { + ndelay(nsecs); + hspi_hw_cs_disable(hspi); + } + spi_finalize_current_message(master); + + return ret; +} + +static int hspi_probe(struct platform_device *pdev) +{ + struct resource *res; + struct spi_master *master; + struct hspi_priv *hspi; + struct clk *clk; + int ret; + + /* get base addr */ + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) { + dev_err(&pdev->dev, "invalid resource\n"); + return -EINVAL; + } + + master = spi_alloc_master(&pdev->dev, sizeof(*hspi)); + if (!master) { + dev_err(&pdev->dev, "spi_alloc_master error.\n"); + return -ENOMEM; + } + + clk = clk_get(&pdev->dev, NULL); + if (IS_ERR(clk)) { + dev_err(&pdev->dev, "couldn't get clock\n"); + ret = -EINVAL; + goto error0; + } + + hspi = spi_master_get_devdata(master); + platform_set_drvdata(pdev, hspi); + + /* init hspi */ + hspi->master = master; + hspi->dev = &pdev->dev; + hspi->clk = clk; + hspi->addr = devm_ioremap(hspi->dev, + res->start, resource_size(res)); + if (!hspi->addr) { + dev_err(&pdev->dev, "ioremap error.\n"); + ret = -ENOMEM; + goto error1; + } + + pm_runtime_enable(&pdev->dev); + + master->bus_num = pdev->id; + master->mode_bits = SPI_CPOL | SPI_CPHA; + master->dev.of_node = pdev->dev.of_node; + master->auto_runtime_pm = true; + master->transfer_one_message = hspi_transfer_one_message; + master->bits_per_word_mask = SPI_BPW_MASK(8); + + ret = devm_spi_register_master(&pdev->dev, master); + if (ret < 0) { + dev_err(&pdev->dev, "spi_register_master error.\n"); + goto error2; + } + + return 0; + + error2: + pm_runtime_disable(&pdev->dev); + error1: + clk_put(clk); + error0: + spi_master_put(master); + + return ret; +} + +static int hspi_remove(struct platform_device *pdev) +{ + struct hspi_priv *hspi = platform_get_drvdata(pdev); + + pm_runtime_disable(&pdev->dev); + + clk_put(hspi->clk); + + return 0; +} + +static const struct of_device_id hspi_of_match[] = { + { .compatible = "renesas,hspi", }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, hspi_of_match); + +static struct platform_driver hspi_driver = { + .probe = hspi_probe, + .remove = hspi_remove, + .driver = { + .name = "sh-hspi", + .of_match_table = hspi_of_match, + }, +}; +module_platform_driver(hspi_driver); + +MODULE_DESCRIPTION("SuperH HSPI bus driver"); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>"); +MODULE_ALIAS("platform:sh-hspi"); diff --git a/drivers/spi/spi-sh-msiof.c b/drivers/spi/spi-sh-msiof.c new file mode 100644 index 000000000..bcc7c635d --- /dev/null +++ b/drivers/spi/spi-sh-msiof.c @@ -0,0 +1,1291 @@ +/* + * SuperH MSIOF SPI Master Interface + * + * Copyright (c) 2009 Magnus Damm + * Copyright (C) 2014 Glider bvba + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + */ + +#include <linux/bitmap.h> +#include <linux/clk.h> +#include <linux/completion.h> +#include <linux/delay.h> +#include <linux/dma-mapping.h> +#include <linux/dmaengine.h> +#include <linux/err.h> +#include <linux/gpio.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/sh_dma.h> + +#include <linux/spi/sh_msiof.h> +#include <linux/spi/spi.h> + +#include <asm/unaligned.h> + + +struct sh_msiof_chipdata { + u16 tx_fifo_size; + u16 rx_fifo_size; + u16 master_flags; +}; + +struct sh_msiof_spi_priv { + struct spi_master *master; + void __iomem *mapbase; + struct clk *clk; + struct platform_device *pdev; + const struct sh_msiof_chipdata *chipdata; + struct sh_msiof_spi_info *info; + struct completion done; + int tx_fifo_size; + int rx_fifo_size; + void *tx_dma_page; + void *rx_dma_page; + dma_addr_t tx_dma_addr; + dma_addr_t rx_dma_addr; +}; + +#define TMDR1 0x00 /* Transmit Mode Register 1 */ +#define TMDR2 0x04 /* Transmit Mode Register 2 */ +#define TMDR3 0x08 /* Transmit Mode Register 3 */ +#define RMDR1 0x10 /* Receive Mode Register 1 */ +#define RMDR2 0x14 /* Receive Mode Register 2 */ +#define RMDR3 0x18 /* Receive Mode Register 3 */ +#define TSCR 0x20 /* Transmit Clock Select Register */ +#define RSCR 0x22 /* Receive Clock Select Register (SH, A1, APE6) */ +#define CTR 0x28 /* Control Register */ +#define FCTR 0x30 /* FIFO Control Register */ +#define STR 0x40 /* Status Register */ +#define IER 0x44 /* Interrupt Enable Register */ +#define TDR1 0x48 /* Transmit Control Data Register 1 (SH, A1) */ +#define TDR2 0x4c /* Transmit Control Data Register 2 (SH, A1) */ +#define TFDR 0x50 /* Transmit FIFO Data Register */ +#define RDR1 0x58 /* Receive Control Data Register 1 (SH, A1) */ +#define RDR2 0x5c /* Receive Control Data Register 2 (SH, A1) */ +#define RFDR 0x60 /* Receive FIFO Data Register */ + +/* TMDR1 and RMDR1 */ +#define MDR1_TRMD 0x80000000 /* Transfer Mode (1 = Master mode) */ +#define MDR1_SYNCMD_MASK 0x30000000 /* SYNC Mode */ +#define MDR1_SYNCMD_SPI 0x20000000 /* Level mode/SPI */ +#define MDR1_SYNCMD_LR 0x30000000 /* L/R mode */ +#define MDR1_SYNCAC_SHIFT 25 /* Sync Polarity (1 = Active-low) */ +#define MDR1_BITLSB_SHIFT 24 /* MSB/LSB First (1 = LSB first) */ +#define MDR1_DTDL_SHIFT 20 /* Data Pin Bit Delay for MSIOF_SYNC */ +#define MDR1_SYNCDL_SHIFT 16 /* Frame Sync Signal Timing Delay */ +#define MDR1_FLD_MASK 0x0000000c /* Frame Sync Signal Interval (0-3) */ +#define MDR1_FLD_SHIFT 2 +#define MDR1_XXSTP 0x00000001 /* Transmission/Reception Stop on FIFO */ +/* TMDR1 */ +#define TMDR1_PCON 0x40000000 /* Transfer Signal Connection */ + +/* TMDR2 and RMDR2 */ +#define MDR2_BITLEN1(i) (((i) - 1) << 24) /* Data Size (8-32 bits) */ +#define MDR2_WDLEN1(i) (((i) - 1) << 16) /* Word Count (1-64/256 (SH, A1))) */ +#define MDR2_GRPMASK1 0x00000001 /* Group Output Mask 1 (SH, A1) */ + +#define MAX_WDLEN 256U + +/* TSCR and RSCR */ +#define SCR_BRPS_MASK 0x1f00 /* Prescaler Setting (1-32) */ +#define SCR_BRPS(i) (((i) - 1) << 8) +#define SCR_BRDV_MASK 0x0007 /* Baud Rate Generator's Division Ratio */ +#define SCR_BRDV_DIV_2 0x0000 +#define SCR_BRDV_DIV_4 0x0001 +#define SCR_BRDV_DIV_8 0x0002 +#define SCR_BRDV_DIV_16 0x0003 +#define SCR_BRDV_DIV_32 0x0004 +#define SCR_BRDV_DIV_1 0x0007 + +/* CTR */ +#define CTR_TSCKIZ_MASK 0xc0000000 /* Transmit Clock I/O Polarity Select */ +#define CTR_TSCKIZ_SCK 0x80000000 /* Disable SCK when TX disabled */ +#define CTR_TSCKIZ_POL_SHIFT 30 /* Transmit Clock Polarity */ +#define CTR_RSCKIZ_MASK 0x30000000 /* Receive Clock Polarity Select */ +#define CTR_RSCKIZ_SCK 0x20000000 /* Must match CTR_TSCKIZ_SCK */ +#define CTR_RSCKIZ_POL_SHIFT 28 /* Receive Clock Polarity */ +#define CTR_TEDG_SHIFT 27 /* Transmit Timing (1 = falling edge) */ +#define CTR_REDG_SHIFT 26 /* Receive Timing (1 = falling edge) */ +#define CTR_TXDIZ_MASK 0x00c00000 /* Pin Output When TX is Disabled */ +#define CTR_TXDIZ_LOW 0x00000000 /* 0 */ +#define CTR_TXDIZ_HIGH 0x00400000 /* 1 */ +#define CTR_TXDIZ_HIZ 0x00800000 /* High-impedance */ +#define CTR_TSCKE 0x00008000 /* Transmit Serial Clock Output Enable */ +#define CTR_TFSE 0x00004000 /* Transmit Frame Sync Signal Output Enable */ +#define CTR_TXE 0x00000200 /* Transmit Enable */ +#define CTR_RXE 0x00000100 /* Receive Enable */ + +/* FCTR */ +#define FCTR_TFWM_MASK 0xe0000000 /* Transmit FIFO Watermark */ +#define FCTR_TFWM_64 0x00000000 /* Transfer Request when 64 empty stages */ +#define FCTR_TFWM_32 0x20000000 /* Transfer Request when 32 empty stages */ +#define FCTR_TFWM_24 0x40000000 /* Transfer Request when 24 empty stages */ +#define FCTR_TFWM_16 0x60000000 /* Transfer Request when 16 empty stages */ +#define FCTR_TFWM_12 0x80000000 /* Transfer Request when 12 empty stages */ +#define FCTR_TFWM_8 0xa0000000 /* Transfer Request when 8 empty stages */ +#define FCTR_TFWM_4 0xc0000000 /* Transfer Request when 4 empty stages */ +#define FCTR_TFWM_1 0xe0000000 /* Transfer Request when 1 empty stage */ +#define FCTR_TFUA_MASK 0x07f00000 /* Transmit FIFO Usable Area */ +#define FCTR_TFUA_SHIFT 20 +#define FCTR_TFUA(i) ((i) << FCTR_TFUA_SHIFT) +#define FCTR_RFWM_MASK 0x0000e000 /* Receive FIFO Watermark */ +#define FCTR_RFWM_1 0x00000000 /* Transfer Request when 1 valid stages */ +#define FCTR_RFWM_4 0x00002000 /* Transfer Request when 4 valid stages */ +#define FCTR_RFWM_8 0x00004000 /* Transfer Request when 8 valid stages */ +#define FCTR_RFWM_16 0x00006000 /* Transfer Request when 16 valid stages */ +#define FCTR_RFWM_32 0x00008000 /* Transfer Request when 32 valid stages */ +#define FCTR_RFWM_64 0x0000a000 /* Transfer Request when 64 valid stages */ +#define FCTR_RFWM_128 0x0000c000 /* Transfer Request when 128 valid stages */ +#define FCTR_RFWM_256 0x0000e000 /* Transfer Request when 256 valid stages */ +#define FCTR_RFUA_MASK 0x00001ff0 /* Receive FIFO Usable Area (0x40 = full) */ +#define FCTR_RFUA_SHIFT 4 +#define FCTR_RFUA(i) ((i) << FCTR_RFUA_SHIFT) + +/* STR */ +#define STR_TFEMP 0x20000000 /* Transmit FIFO Empty */ +#define STR_TDREQ 0x10000000 /* Transmit Data Transfer Request */ +#define STR_TEOF 0x00800000 /* Frame Transmission End */ +#define STR_TFSERR 0x00200000 /* Transmit Frame Synchronization Error */ +#define STR_TFOVF 0x00100000 /* Transmit FIFO Overflow */ +#define STR_TFUDF 0x00080000 /* Transmit FIFO Underflow */ +#define STR_RFFUL 0x00002000 /* Receive FIFO Full */ +#define STR_RDREQ 0x00001000 /* Receive Data Transfer Request */ +#define STR_REOF 0x00000080 /* Frame Reception End */ +#define STR_RFSERR 0x00000020 /* Receive Frame Synchronization Error */ +#define STR_RFUDF 0x00000010 /* Receive FIFO Underflow */ +#define STR_RFOVF 0x00000008 /* Receive FIFO Overflow */ + +/* IER */ +#define IER_TDMAE 0x80000000 /* Transmit Data DMA Transfer Req. Enable */ +#define IER_TFEMPE 0x20000000 /* Transmit FIFO Empty Enable */ +#define IER_TDREQE 0x10000000 /* Transmit Data Transfer Request Enable */ +#define IER_TEOFE 0x00800000 /* Frame Transmission End Enable */ +#define IER_TFSERRE 0x00200000 /* Transmit Frame Sync Error Enable */ +#define IER_TFOVFE 0x00100000 /* Transmit FIFO Overflow Enable */ +#define IER_TFUDFE 0x00080000 /* Transmit FIFO Underflow Enable */ +#define IER_RDMAE 0x00008000 /* Receive Data DMA Transfer Req. Enable */ +#define IER_RFFULE 0x00002000 /* Receive FIFO Full Enable */ +#define IER_RDREQE 0x00001000 /* Receive Data Transfer Request Enable */ +#define IER_REOFE 0x00000080 /* Frame Reception End Enable */ +#define IER_RFSERRE 0x00000020 /* Receive Frame Sync Error Enable */ +#define IER_RFUDFE 0x00000010 /* Receive FIFO Underflow Enable */ +#define IER_RFOVFE 0x00000008 /* Receive FIFO Overflow Enable */ + + +static u32 sh_msiof_read(struct sh_msiof_spi_priv *p, int reg_offs) +{ + switch (reg_offs) { + case TSCR: + case RSCR: + return ioread16(p->mapbase + reg_offs); + default: + return ioread32(p->mapbase + reg_offs); + } +} + +static void sh_msiof_write(struct sh_msiof_spi_priv *p, int reg_offs, + u32 value) +{ + switch (reg_offs) { + case TSCR: + case RSCR: + iowrite16(value, p->mapbase + reg_offs); + break; + default: + iowrite32(value, p->mapbase + reg_offs); + break; + } +} + +static int sh_msiof_modify_ctr_wait(struct sh_msiof_spi_priv *p, + u32 clr, u32 set) +{ + u32 mask = clr | set; + u32 data; + int k; + + data = sh_msiof_read(p, CTR); + data &= ~clr; + data |= set; + sh_msiof_write(p, CTR, data); + + for (k = 100; k > 0; k--) { + if ((sh_msiof_read(p, CTR) & mask) == set) + break; + + udelay(10); + } + + return k > 0 ? 0 : -ETIMEDOUT; +} + +static irqreturn_t sh_msiof_spi_irq(int irq, void *data) +{ + struct sh_msiof_spi_priv *p = data; + + /* just disable the interrupt and wake up */ + sh_msiof_write(p, IER, 0); + complete(&p->done); + + return IRQ_HANDLED; +} + +static struct { + unsigned short div; + unsigned short brdv; +} const sh_msiof_spi_div_table[] = { + { 1, SCR_BRDV_DIV_1 }, + { 2, SCR_BRDV_DIV_2 }, + { 4, SCR_BRDV_DIV_4 }, + { 8, SCR_BRDV_DIV_8 }, + { 16, SCR_BRDV_DIV_16 }, + { 32, SCR_BRDV_DIV_32 }, +}; + +static void sh_msiof_spi_set_clk_regs(struct sh_msiof_spi_priv *p, + unsigned long parent_rate, u32 spi_hz) +{ + unsigned long div = 1024; + u32 brps, scr; + size_t k; + + if (!WARN_ON(!spi_hz || !parent_rate)) + div = DIV_ROUND_UP(parent_rate, spi_hz); + + for (k = 0; k < ARRAY_SIZE(sh_msiof_spi_div_table); k++) { + brps = DIV_ROUND_UP(div, sh_msiof_spi_div_table[k].div); + if (brps <= 32) /* max of brdv is 32 */ + break; + } + + k = min_t(int, k, ARRAY_SIZE(sh_msiof_spi_div_table) - 1); + + scr = sh_msiof_spi_div_table[k].brdv | SCR_BRPS(brps); + sh_msiof_write(p, TSCR, scr); + if (!(p->chipdata->master_flags & SPI_MASTER_MUST_TX)) + sh_msiof_write(p, RSCR, scr); +} + +static u32 sh_msiof_get_delay_bit(u32 dtdl_or_syncdl) +{ + /* + * DTDL/SYNCDL bit : p->info->dtdl or p->info->syncdl + * b'000 : 0 + * b'001 : 100 + * b'010 : 200 + * b'011 (SYNCDL only) : 300 + * b'101 : 50 + * b'110 : 150 + */ + if (dtdl_or_syncdl % 100) + return dtdl_or_syncdl / 100 + 5; + else + return dtdl_or_syncdl / 100; +} + +static u32 sh_msiof_spi_get_dtdl_and_syncdl(struct sh_msiof_spi_priv *p) +{ + u32 val; + + if (!p->info) + return 0; + + /* check if DTDL and SYNCDL is allowed value */ + if (p->info->dtdl > 200 || p->info->syncdl > 300) { + dev_warn(&p->pdev->dev, "DTDL or SYNCDL is too large\n"); + return 0; + } + + /* check if the sum of DTDL and SYNCDL becomes an integer value */ + if ((p->info->dtdl + p->info->syncdl) % 100) { + dev_warn(&p->pdev->dev, "the sum of DTDL/SYNCDL is not good\n"); + return 0; + } + + val = sh_msiof_get_delay_bit(p->info->dtdl) << MDR1_DTDL_SHIFT; + val |= sh_msiof_get_delay_bit(p->info->syncdl) << MDR1_SYNCDL_SHIFT; + + return val; +} + +static void sh_msiof_spi_set_pin_regs(struct sh_msiof_spi_priv *p, + u32 cpol, u32 cpha, + u32 tx_hi_z, u32 lsb_first, u32 cs_high) +{ + u32 tmp; + int edge; + + /* + * CPOL CPHA TSCKIZ RSCKIZ TEDG REDG + * 0 0 10 10 1 1 + * 0 1 10 10 0 0 + * 1 0 11 11 0 0 + * 1 1 11 11 1 1 + */ + tmp = MDR1_SYNCMD_SPI | 1 << MDR1_FLD_SHIFT | MDR1_XXSTP; + tmp |= !cs_high << MDR1_SYNCAC_SHIFT; + tmp |= lsb_first << MDR1_BITLSB_SHIFT; + tmp |= sh_msiof_spi_get_dtdl_and_syncdl(p); + sh_msiof_write(p, TMDR1, tmp | MDR1_TRMD | TMDR1_PCON); + if (p->chipdata->master_flags & SPI_MASTER_MUST_TX) { + /* These bits are reserved if RX needs TX */ + tmp &= ~0x0000ffff; + } + sh_msiof_write(p, RMDR1, tmp); + + tmp = 0; + tmp |= CTR_TSCKIZ_SCK | cpol << CTR_TSCKIZ_POL_SHIFT; + tmp |= CTR_RSCKIZ_SCK | cpol << CTR_RSCKIZ_POL_SHIFT; + + edge = cpol ^ !cpha; + + tmp |= edge << CTR_TEDG_SHIFT; + tmp |= edge << CTR_REDG_SHIFT; + tmp |= tx_hi_z ? CTR_TXDIZ_HIZ : CTR_TXDIZ_LOW; + sh_msiof_write(p, CTR, tmp); +} + +static void sh_msiof_spi_set_mode_regs(struct sh_msiof_spi_priv *p, + const void *tx_buf, void *rx_buf, + u32 bits, u32 words) +{ + u32 dr2 = MDR2_BITLEN1(bits) | MDR2_WDLEN1(words); + + if (tx_buf || (p->chipdata->master_flags & SPI_MASTER_MUST_TX)) + sh_msiof_write(p, TMDR2, dr2); + else + sh_msiof_write(p, TMDR2, dr2 | MDR2_GRPMASK1); + + if (rx_buf) + sh_msiof_write(p, RMDR2, dr2); +} + +static void sh_msiof_reset_str(struct sh_msiof_spi_priv *p) +{ + sh_msiof_write(p, STR, sh_msiof_read(p, STR)); +} + +static void sh_msiof_spi_write_fifo_8(struct sh_msiof_spi_priv *p, + const void *tx_buf, int words, int fs) +{ + const u8 *buf_8 = tx_buf; + int k; + + for (k = 0; k < words; k++) + sh_msiof_write(p, TFDR, buf_8[k] << fs); +} + +static void sh_msiof_spi_write_fifo_16(struct sh_msiof_spi_priv *p, + const void *tx_buf, int words, int fs) +{ + const u16 *buf_16 = tx_buf; + int k; + + for (k = 0; k < words; k++) + sh_msiof_write(p, TFDR, buf_16[k] << fs); +} + +static void sh_msiof_spi_write_fifo_16u(struct sh_msiof_spi_priv *p, + const void *tx_buf, int words, int fs) +{ + const u16 *buf_16 = tx_buf; + int k; + + for (k = 0; k < words; k++) + sh_msiof_write(p, TFDR, get_unaligned(&buf_16[k]) << fs); +} + +static void sh_msiof_spi_write_fifo_32(struct sh_msiof_spi_priv *p, + const void *tx_buf, int words, int fs) +{ + const u32 *buf_32 = tx_buf; + int k; + + for (k = 0; k < words; k++) + sh_msiof_write(p, TFDR, buf_32[k] << fs); +} + +static void sh_msiof_spi_write_fifo_32u(struct sh_msiof_spi_priv *p, + const void *tx_buf, int words, int fs) +{ + const u32 *buf_32 = tx_buf; + int k; + + for (k = 0; k < words; k++) + sh_msiof_write(p, TFDR, get_unaligned(&buf_32[k]) << fs); +} + +static void sh_msiof_spi_write_fifo_s32(struct sh_msiof_spi_priv *p, + const void *tx_buf, int words, int fs) +{ + const u32 *buf_32 = tx_buf; + int k; + + for (k = 0; k < words; k++) + sh_msiof_write(p, TFDR, swab32(buf_32[k] << fs)); +} + +static void sh_msiof_spi_write_fifo_s32u(struct sh_msiof_spi_priv *p, + const void *tx_buf, int words, int fs) +{ + const u32 *buf_32 = tx_buf; + int k; + + for (k = 0; k < words; k++) + sh_msiof_write(p, TFDR, swab32(get_unaligned(&buf_32[k]) << fs)); +} + +static void sh_msiof_spi_read_fifo_8(struct sh_msiof_spi_priv *p, + void *rx_buf, int words, int fs) +{ + u8 *buf_8 = rx_buf; + int k; + + for (k = 0; k < words; k++) + buf_8[k] = sh_msiof_read(p, RFDR) >> fs; +} + +static void sh_msiof_spi_read_fifo_16(struct sh_msiof_spi_priv *p, + void *rx_buf, int words, int fs) +{ + u16 *buf_16 = rx_buf; + int k; + + for (k = 0; k < words; k++) + buf_16[k] = sh_msiof_read(p, RFDR) >> fs; +} + +static void sh_msiof_spi_read_fifo_16u(struct sh_msiof_spi_priv *p, + void *rx_buf, int words, int fs) +{ + u16 *buf_16 = rx_buf; + int k; + + for (k = 0; k < words; k++) + put_unaligned(sh_msiof_read(p, RFDR) >> fs, &buf_16[k]); +} + +static void sh_msiof_spi_read_fifo_32(struct sh_msiof_spi_priv *p, + void *rx_buf, int words, int fs) +{ + u32 *buf_32 = rx_buf; + int k; + + for (k = 0; k < words; k++) + buf_32[k] = sh_msiof_read(p, RFDR) >> fs; +} + +static void sh_msiof_spi_read_fifo_32u(struct sh_msiof_spi_priv *p, + void *rx_buf, int words, int fs) +{ + u32 *buf_32 = rx_buf; + int k; + + for (k = 0; k < words; k++) + put_unaligned(sh_msiof_read(p, RFDR) >> fs, &buf_32[k]); +} + +static void sh_msiof_spi_read_fifo_s32(struct sh_msiof_spi_priv *p, + void *rx_buf, int words, int fs) +{ + u32 *buf_32 = rx_buf; + int k; + + for (k = 0; k < words; k++) + buf_32[k] = swab32(sh_msiof_read(p, RFDR) >> fs); +} + +static void sh_msiof_spi_read_fifo_s32u(struct sh_msiof_spi_priv *p, + void *rx_buf, int words, int fs) +{ + u32 *buf_32 = rx_buf; + int k; + + for (k = 0; k < words; k++) + put_unaligned(swab32(sh_msiof_read(p, RFDR) >> fs), &buf_32[k]); +} + +static int sh_msiof_spi_setup(struct spi_device *spi) +{ + struct device_node *np = spi->master->dev.of_node; + struct sh_msiof_spi_priv *p = spi_master_get_devdata(spi->master); + + pm_runtime_get_sync(&p->pdev->dev); + + if (!np) { + /* + * Use spi->controller_data for CS (same strategy as spi_gpio), + * if any. otherwise let HW control CS + */ + spi->cs_gpio = (uintptr_t)spi->controller_data; + } + + /* Configure pins before deasserting CS */ + sh_msiof_spi_set_pin_regs(p, !!(spi->mode & SPI_CPOL), + !!(spi->mode & SPI_CPHA), + !!(spi->mode & SPI_3WIRE), + !!(spi->mode & SPI_LSB_FIRST), + !!(spi->mode & SPI_CS_HIGH)); + + if (spi->cs_gpio >= 0) + gpio_set_value(spi->cs_gpio, !(spi->mode & SPI_CS_HIGH)); + + + pm_runtime_put(&p->pdev->dev); + + return 0; +} + +static int sh_msiof_prepare_message(struct spi_master *master, + struct spi_message *msg) +{ + struct sh_msiof_spi_priv *p = spi_master_get_devdata(master); + const struct spi_device *spi = msg->spi; + + /* Configure pins before asserting CS */ + sh_msiof_spi_set_pin_regs(p, !!(spi->mode & SPI_CPOL), + !!(spi->mode & SPI_CPHA), + !!(spi->mode & SPI_3WIRE), + !!(spi->mode & SPI_LSB_FIRST), + !!(spi->mode & SPI_CS_HIGH)); + return 0; +} + +static int sh_msiof_spi_start(struct sh_msiof_spi_priv *p, void *rx_buf) +{ + int ret; + + /* setup clock and rx/tx signals */ + ret = sh_msiof_modify_ctr_wait(p, 0, CTR_TSCKE); + if (rx_buf && !ret) + ret = sh_msiof_modify_ctr_wait(p, 0, CTR_RXE); + if (!ret) + ret = sh_msiof_modify_ctr_wait(p, 0, CTR_TXE); + + /* start by setting frame bit */ + if (!ret) + ret = sh_msiof_modify_ctr_wait(p, 0, CTR_TFSE); + + return ret; +} + +static int sh_msiof_spi_stop(struct sh_msiof_spi_priv *p, void *rx_buf) +{ + int ret; + + /* shut down frame, rx/tx and clock signals */ + ret = sh_msiof_modify_ctr_wait(p, CTR_TFSE, 0); + if (!ret) + ret = sh_msiof_modify_ctr_wait(p, CTR_TXE, 0); + if (rx_buf && !ret) + ret = sh_msiof_modify_ctr_wait(p, CTR_RXE, 0); + if (!ret) + ret = sh_msiof_modify_ctr_wait(p, CTR_TSCKE, 0); + + return ret; +} + +static int sh_msiof_spi_txrx_once(struct sh_msiof_spi_priv *p, + void (*tx_fifo)(struct sh_msiof_spi_priv *, + const void *, int, int), + void (*rx_fifo)(struct sh_msiof_spi_priv *, + void *, int, int), + const void *tx_buf, void *rx_buf, + int words, int bits) +{ + int fifo_shift; + int ret; + + /* limit maximum word transfer to rx/tx fifo size */ + if (tx_buf) + words = min_t(int, words, p->tx_fifo_size); + if (rx_buf) + words = min_t(int, words, p->rx_fifo_size); + + /* the fifo contents need shifting */ + fifo_shift = 32 - bits; + + /* default FIFO watermarks for PIO */ + sh_msiof_write(p, FCTR, 0); + + /* setup msiof transfer mode registers */ + sh_msiof_spi_set_mode_regs(p, tx_buf, rx_buf, bits, words); + sh_msiof_write(p, IER, IER_TEOFE | IER_REOFE); + + /* write tx fifo */ + if (tx_buf) + tx_fifo(p, tx_buf, words, fifo_shift); + + reinit_completion(&p->done); + + ret = sh_msiof_spi_start(p, rx_buf); + if (ret) { + dev_err(&p->pdev->dev, "failed to start hardware\n"); + goto stop_ier; + } + + /* wait for tx fifo to be emptied / rx fifo to be filled */ + if (!wait_for_completion_timeout(&p->done, HZ)) { + dev_err(&p->pdev->dev, "PIO timeout\n"); + ret = -ETIMEDOUT; + goto stop_reset; + } + + /* read rx fifo */ + if (rx_buf) + rx_fifo(p, rx_buf, words, fifo_shift); + + /* clear status bits */ + sh_msiof_reset_str(p); + + ret = sh_msiof_spi_stop(p, rx_buf); + if (ret) { + dev_err(&p->pdev->dev, "failed to shut down hardware\n"); + return ret; + } + + return words; + +stop_reset: + sh_msiof_reset_str(p); + sh_msiof_spi_stop(p, rx_buf); +stop_ier: + sh_msiof_write(p, IER, 0); + return ret; +} + +static void sh_msiof_dma_complete(void *arg) +{ + struct sh_msiof_spi_priv *p = arg; + + sh_msiof_write(p, IER, 0); + complete(&p->done); +} + +static int sh_msiof_dma_once(struct sh_msiof_spi_priv *p, const void *tx, + void *rx, unsigned int len) +{ + u32 ier_bits = 0; + struct dma_async_tx_descriptor *desc_tx = NULL, *desc_rx = NULL; + dma_cookie_t cookie; + int ret; + + /* First prepare and submit the DMA request(s), as this may fail */ + if (rx) { + ier_bits |= IER_RDREQE | IER_RDMAE; + desc_rx = dmaengine_prep_slave_single(p->master->dma_rx, + p->rx_dma_addr, len, DMA_FROM_DEVICE, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + if (!desc_rx) + return -EAGAIN; + + desc_rx->callback = sh_msiof_dma_complete; + desc_rx->callback_param = p; + cookie = dmaengine_submit(desc_rx); + if (dma_submit_error(cookie)) + return cookie; + } + + if (tx) { + ier_bits |= IER_TDREQE | IER_TDMAE; + dma_sync_single_for_device(p->master->dma_tx->device->dev, + p->tx_dma_addr, len, DMA_TO_DEVICE); + desc_tx = dmaengine_prep_slave_single(p->master->dma_tx, + p->tx_dma_addr, len, DMA_TO_DEVICE, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + if (!desc_tx) { + ret = -EAGAIN; + goto no_dma_tx; + } + + if (rx) { + /* No callback */ + desc_tx->callback = NULL; + } else { + desc_tx->callback = sh_msiof_dma_complete; + desc_tx->callback_param = p; + } + cookie = dmaengine_submit(desc_tx); + if (dma_submit_error(cookie)) { + ret = cookie; + goto no_dma_tx; + } + } + + /* 1 stage FIFO watermarks for DMA */ + sh_msiof_write(p, FCTR, FCTR_TFWM_1 | FCTR_RFWM_1); + + /* setup msiof transfer mode registers (32-bit words) */ + sh_msiof_spi_set_mode_regs(p, tx, rx, 32, len / 4); + + sh_msiof_write(p, IER, ier_bits); + + reinit_completion(&p->done); + + /* Now start DMA */ + if (rx) + dma_async_issue_pending(p->master->dma_rx); + if (tx) + dma_async_issue_pending(p->master->dma_tx); + + ret = sh_msiof_spi_start(p, rx); + if (ret) { + dev_err(&p->pdev->dev, "failed to start hardware\n"); + goto stop_dma; + } + + /* wait for tx fifo to be emptied / rx fifo to be filled */ + if (!wait_for_completion_timeout(&p->done, HZ)) { + dev_err(&p->pdev->dev, "DMA timeout\n"); + ret = -ETIMEDOUT; + goto stop_reset; + } + + /* clear status bits */ + sh_msiof_reset_str(p); + + ret = sh_msiof_spi_stop(p, rx); + if (ret) { + dev_err(&p->pdev->dev, "failed to shut down hardware\n"); + return ret; + } + + if (rx) + dma_sync_single_for_cpu(p->master->dma_rx->device->dev, + p->rx_dma_addr, len, + DMA_FROM_DEVICE); + + return 0; + +stop_reset: + sh_msiof_reset_str(p); + sh_msiof_spi_stop(p, rx); +stop_dma: + if (tx) + dmaengine_terminate_all(p->master->dma_tx); +no_dma_tx: + if (rx) + dmaengine_terminate_all(p->master->dma_rx); + sh_msiof_write(p, IER, 0); + return ret; +} + +static void copy_bswap32(u32 *dst, const u32 *src, unsigned int words) +{ + /* src or dst can be unaligned, but not both */ + if ((unsigned long)src & 3) { + while (words--) { + *dst++ = swab32(get_unaligned(src)); + src++; + } + } else if ((unsigned long)dst & 3) { + while (words--) { + put_unaligned(swab32(*src++), dst); + dst++; + } + } else { + while (words--) + *dst++ = swab32(*src++); + } +} + +static void copy_wswap32(u32 *dst, const u32 *src, unsigned int words) +{ + /* src or dst can be unaligned, but not both */ + if ((unsigned long)src & 3) { + while (words--) { + *dst++ = swahw32(get_unaligned(src)); + src++; + } + } else if ((unsigned long)dst & 3) { + while (words--) { + put_unaligned(swahw32(*src++), dst); + dst++; + } + } else { + while (words--) + *dst++ = swahw32(*src++); + } +} + +static void copy_plain32(u32 *dst, const u32 *src, unsigned int words) +{ + memcpy(dst, src, words * 4); +} + +static int sh_msiof_transfer_one(struct spi_master *master, + struct spi_device *spi, + struct spi_transfer *t) +{ + struct sh_msiof_spi_priv *p = spi_master_get_devdata(master); + void (*copy32)(u32 *, const u32 *, unsigned int); + void (*tx_fifo)(struct sh_msiof_spi_priv *, const void *, int, int); + void (*rx_fifo)(struct sh_msiof_spi_priv *, void *, int, int); + const void *tx_buf = t->tx_buf; + void *rx_buf = t->rx_buf; + unsigned int len = t->len; + unsigned int bits = t->bits_per_word; + unsigned int bytes_per_word; + unsigned int words; + int n; + bool swab; + int ret; + + /* setup clocks (clock already enabled in chipselect()) */ + sh_msiof_spi_set_clk_regs(p, clk_get_rate(p->clk), t->speed_hz); + + while (master->dma_tx && len > 15) { + /* + * DMA supports 32-bit words only, hence pack 8-bit and 16-bit + * words, with byte resp. word swapping. + */ + unsigned int l = min(len, MAX_WDLEN * 4); + + if (bits <= 8) { + if (l & 3) + break; + copy32 = copy_bswap32; + } else if (bits <= 16) { + if (l & 1) + break; + copy32 = copy_wswap32; + } else { + copy32 = copy_plain32; + } + + if (tx_buf) + copy32(p->tx_dma_page, tx_buf, l / 4); + + ret = sh_msiof_dma_once(p, tx_buf, rx_buf, l); + if (ret == -EAGAIN) { + pr_warn_once("%s %s: DMA not available, falling back to PIO\n", + dev_driver_string(&p->pdev->dev), + dev_name(&p->pdev->dev)); + break; + } + if (ret) + return ret; + + if (rx_buf) { + copy32(rx_buf, p->rx_dma_page, l / 4); + rx_buf += l; + } + if (tx_buf) + tx_buf += l; + + len -= l; + if (!len) + return 0; + } + + if (bits <= 8 && len > 15 && !(len & 3)) { + bits = 32; + swab = true; + } else { + swab = false; + } + + /* setup bytes per word and fifo read/write functions */ + if (bits <= 8) { + bytes_per_word = 1; + tx_fifo = sh_msiof_spi_write_fifo_8; + rx_fifo = sh_msiof_spi_read_fifo_8; + } else if (bits <= 16) { + bytes_per_word = 2; + if ((unsigned long)tx_buf & 0x01) + tx_fifo = sh_msiof_spi_write_fifo_16u; + else + tx_fifo = sh_msiof_spi_write_fifo_16; + + if ((unsigned long)rx_buf & 0x01) + rx_fifo = sh_msiof_spi_read_fifo_16u; + else + rx_fifo = sh_msiof_spi_read_fifo_16; + } else if (swab) { + bytes_per_word = 4; + if ((unsigned long)tx_buf & 0x03) + tx_fifo = sh_msiof_spi_write_fifo_s32u; + else + tx_fifo = sh_msiof_spi_write_fifo_s32; + + if ((unsigned long)rx_buf & 0x03) + rx_fifo = sh_msiof_spi_read_fifo_s32u; + else + rx_fifo = sh_msiof_spi_read_fifo_s32; + } else { + bytes_per_word = 4; + if ((unsigned long)tx_buf & 0x03) + tx_fifo = sh_msiof_spi_write_fifo_32u; + else + tx_fifo = sh_msiof_spi_write_fifo_32; + + if ((unsigned long)rx_buf & 0x03) + rx_fifo = sh_msiof_spi_read_fifo_32u; + else + rx_fifo = sh_msiof_spi_read_fifo_32; + } + + /* transfer in fifo sized chunks */ + words = len / bytes_per_word; + + while (words > 0) { + n = sh_msiof_spi_txrx_once(p, tx_fifo, rx_fifo, tx_buf, rx_buf, + words, bits); + if (n < 0) + return n; + + if (tx_buf) + tx_buf += n * bytes_per_word; + if (rx_buf) + rx_buf += n * bytes_per_word; + words -= n; + } + + return 0; +} + +static const struct sh_msiof_chipdata sh_data = { + .tx_fifo_size = 64, + .rx_fifo_size = 64, + .master_flags = 0, +}; + +static const struct sh_msiof_chipdata r8a779x_data = { + .tx_fifo_size = 64, + .rx_fifo_size = 256, + .master_flags = SPI_MASTER_MUST_TX, +}; + +static const struct of_device_id sh_msiof_match[] = { + { .compatible = "renesas,sh-msiof", .data = &sh_data }, + { .compatible = "renesas,sh-mobile-msiof", .data = &sh_data }, + { .compatible = "renesas,msiof-r8a7790", .data = &r8a779x_data }, + { .compatible = "renesas,msiof-r8a7791", .data = &r8a779x_data }, + { .compatible = "renesas,msiof-r8a7792", .data = &r8a779x_data }, + { .compatible = "renesas,msiof-r8a7793", .data = &r8a779x_data }, + { .compatible = "renesas,msiof-r8a7794", .data = &r8a779x_data }, + {}, +}; +MODULE_DEVICE_TABLE(of, sh_msiof_match); + +#ifdef CONFIG_OF +static struct sh_msiof_spi_info *sh_msiof_spi_parse_dt(struct device *dev) +{ + struct sh_msiof_spi_info *info; + struct device_node *np = dev->of_node; + u32 num_cs = 1; + + info = devm_kzalloc(dev, sizeof(struct sh_msiof_spi_info), GFP_KERNEL); + if (!info) + return NULL; + + /* Parse the MSIOF properties */ + of_property_read_u32(np, "num-cs", &num_cs); + of_property_read_u32(np, "renesas,tx-fifo-size", + &info->tx_fifo_override); + of_property_read_u32(np, "renesas,rx-fifo-size", + &info->rx_fifo_override); + of_property_read_u32(np, "renesas,dtdl", &info->dtdl); + of_property_read_u32(np, "renesas,syncdl", &info->syncdl); + + info->num_chipselect = num_cs; + + return info; +} +#else +static struct sh_msiof_spi_info *sh_msiof_spi_parse_dt(struct device *dev) +{ + return NULL; +} +#endif + +static struct dma_chan *sh_msiof_request_dma_chan(struct device *dev, + enum dma_transfer_direction dir, unsigned int id, dma_addr_t port_addr) +{ + dma_cap_mask_t mask; + struct dma_chan *chan; + struct dma_slave_config cfg; + int ret; + + dma_cap_zero(mask); + dma_cap_set(DMA_SLAVE, mask); + + chan = dma_request_slave_channel_compat(mask, shdma_chan_filter, + (void *)(unsigned long)id, dev, + dir == DMA_MEM_TO_DEV ? "tx" : "rx"); + if (!chan) { + dev_warn(dev, "dma_request_slave_channel_compat failed\n"); + return NULL; + } + + memset(&cfg, 0, sizeof(cfg)); + cfg.direction = dir; + if (dir == DMA_MEM_TO_DEV) { + cfg.dst_addr = port_addr; + cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; + } else { + cfg.src_addr = port_addr; + cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; + } + + ret = dmaengine_slave_config(chan, &cfg); + if (ret) { + dev_warn(dev, "dmaengine_slave_config failed %d\n", ret); + dma_release_channel(chan); + return NULL; + } + + return chan; +} + +static int sh_msiof_request_dma(struct sh_msiof_spi_priv *p) +{ + struct platform_device *pdev = p->pdev; + struct device *dev = &pdev->dev; + const struct sh_msiof_spi_info *info = dev_get_platdata(dev); + unsigned int dma_tx_id, dma_rx_id; + const struct resource *res; + struct spi_master *master; + struct device *tx_dev, *rx_dev; + + if (dev->of_node) { + /* In the OF case we will get the slave IDs from the DT */ + dma_tx_id = 0; + dma_rx_id = 0; + } else if (info && info->dma_tx_id && info->dma_rx_id) { + dma_tx_id = info->dma_tx_id; + dma_rx_id = info->dma_rx_id; + } else { + /* The driver assumes no error */ + return 0; + } + + /* The DMA engine uses the second register set, if present */ + res = platform_get_resource(pdev, IORESOURCE_MEM, 1); + if (!res) + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + + master = p->master; + master->dma_tx = sh_msiof_request_dma_chan(dev, DMA_MEM_TO_DEV, + dma_tx_id, + res->start + TFDR); + if (!master->dma_tx) + return -ENODEV; + + master->dma_rx = sh_msiof_request_dma_chan(dev, DMA_DEV_TO_MEM, + dma_rx_id, + res->start + RFDR); + if (!master->dma_rx) + goto free_tx_chan; + + p->tx_dma_page = (void *)__get_free_page(GFP_KERNEL | GFP_DMA); + if (!p->tx_dma_page) + goto free_rx_chan; + + p->rx_dma_page = (void *)__get_free_page(GFP_KERNEL | GFP_DMA); + if (!p->rx_dma_page) + goto free_tx_page; + + tx_dev = master->dma_tx->device->dev; + p->tx_dma_addr = dma_map_single(tx_dev, p->tx_dma_page, PAGE_SIZE, + DMA_TO_DEVICE); + if (dma_mapping_error(tx_dev, p->tx_dma_addr)) + goto free_rx_page; + + rx_dev = master->dma_rx->device->dev; + p->rx_dma_addr = dma_map_single(rx_dev, p->rx_dma_page, PAGE_SIZE, + DMA_FROM_DEVICE); + if (dma_mapping_error(rx_dev, p->rx_dma_addr)) + goto unmap_tx_page; + + dev_info(dev, "DMA available"); + return 0; + +unmap_tx_page: + dma_unmap_single(tx_dev, p->tx_dma_addr, PAGE_SIZE, DMA_TO_DEVICE); +free_rx_page: + free_page((unsigned long)p->rx_dma_page); +free_tx_page: + free_page((unsigned long)p->tx_dma_page); +free_rx_chan: + dma_release_channel(master->dma_rx); +free_tx_chan: + dma_release_channel(master->dma_tx); + master->dma_tx = NULL; + return -ENODEV; +} + +static void sh_msiof_release_dma(struct sh_msiof_spi_priv *p) +{ + struct spi_master *master = p->master; + struct device *dev; + + if (!master->dma_tx) + return; + + dev = &p->pdev->dev; + dma_unmap_single(master->dma_rx->device->dev, p->rx_dma_addr, + PAGE_SIZE, DMA_FROM_DEVICE); + dma_unmap_single(master->dma_tx->device->dev, p->tx_dma_addr, + PAGE_SIZE, DMA_TO_DEVICE); + free_page((unsigned long)p->rx_dma_page); + free_page((unsigned long)p->tx_dma_page); + dma_release_channel(master->dma_rx); + dma_release_channel(master->dma_tx); +} + +static int sh_msiof_spi_probe(struct platform_device *pdev) +{ + struct resource *r; + struct spi_master *master; + const struct of_device_id *of_id; + struct sh_msiof_spi_priv *p; + int i; + int ret; + + master = spi_alloc_master(&pdev->dev, sizeof(struct sh_msiof_spi_priv)); + if (master == NULL) { + dev_err(&pdev->dev, "failed to allocate spi master\n"); + return -ENOMEM; + } + + p = spi_master_get_devdata(master); + + platform_set_drvdata(pdev, p); + p->master = master; + + of_id = of_match_device(sh_msiof_match, &pdev->dev); + if (of_id) { + p->chipdata = of_id->data; + p->info = sh_msiof_spi_parse_dt(&pdev->dev); + } else { + p->chipdata = (const void *)pdev->id_entry->driver_data; + p->info = dev_get_platdata(&pdev->dev); + } + + if (!p->info) { + dev_err(&pdev->dev, "failed to obtain device info\n"); + ret = -ENXIO; + goto err1; + } + + init_completion(&p->done); + + p->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(p->clk)) { + dev_err(&pdev->dev, "cannot get clock\n"); + ret = PTR_ERR(p->clk); + goto err1; + } + + i = platform_get_irq(pdev, 0); + if (i < 0) { + dev_err(&pdev->dev, "cannot get platform IRQ\n"); + ret = -ENOENT; + goto err1; + } + + r = platform_get_resource(pdev, IORESOURCE_MEM, 0); + p->mapbase = devm_ioremap_resource(&pdev->dev, r); + if (IS_ERR(p->mapbase)) { + ret = PTR_ERR(p->mapbase); + goto err1; + } + + ret = devm_request_irq(&pdev->dev, i, sh_msiof_spi_irq, 0, + dev_name(&pdev->dev), p); + if (ret) { + dev_err(&pdev->dev, "unable to request irq\n"); + goto err1; + } + + p->pdev = pdev; + pm_runtime_enable(&pdev->dev); + + /* Platform data may override FIFO sizes */ + p->tx_fifo_size = p->chipdata->tx_fifo_size; + p->rx_fifo_size = p->chipdata->rx_fifo_size; + if (p->info->tx_fifo_override) + p->tx_fifo_size = p->info->tx_fifo_override; + if (p->info->rx_fifo_override) + p->rx_fifo_size = p->info->rx_fifo_override; + + /* init master code */ + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH; + master->mode_bits |= SPI_LSB_FIRST | SPI_3WIRE; + master->flags = p->chipdata->master_flags; + master->bus_num = pdev->id; + master->dev.of_node = pdev->dev.of_node; + master->num_chipselect = p->info->num_chipselect; + master->setup = sh_msiof_spi_setup; + master->prepare_message = sh_msiof_prepare_message; + master->bits_per_word_mask = SPI_BPW_RANGE_MASK(8, 32); + master->auto_runtime_pm = true; + master->transfer_one = sh_msiof_transfer_one; + + ret = sh_msiof_request_dma(p); + if (ret < 0) + dev_warn(&pdev->dev, "DMA not available, using PIO\n"); + + ret = devm_spi_register_master(&pdev->dev, master); + if (ret < 0) { + dev_err(&pdev->dev, "spi_register_master error.\n"); + goto err2; + } + + return 0; + + err2: + sh_msiof_release_dma(p); + pm_runtime_disable(&pdev->dev); + err1: + spi_master_put(master); + return ret; +} + +static int sh_msiof_spi_remove(struct platform_device *pdev) +{ + struct sh_msiof_spi_priv *p = platform_get_drvdata(pdev); + + sh_msiof_release_dma(p); + pm_runtime_disable(&pdev->dev); + return 0; +} + +static struct platform_device_id spi_driver_ids[] = { + { "spi_sh_msiof", (kernel_ulong_t)&sh_data }, + { "spi_r8a7790_msiof", (kernel_ulong_t)&r8a779x_data }, + { "spi_r8a7791_msiof", (kernel_ulong_t)&r8a779x_data }, + { "spi_r8a7792_msiof", (kernel_ulong_t)&r8a779x_data }, + { "spi_r8a7793_msiof", (kernel_ulong_t)&r8a779x_data }, + { "spi_r8a7794_msiof", (kernel_ulong_t)&r8a779x_data }, + {}, +}; +MODULE_DEVICE_TABLE(platform, spi_driver_ids); + +static struct platform_driver sh_msiof_spi_drv = { + .probe = sh_msiof_spi_probe, + .remove = sh_msiof_spi_remove, + .id_table = spi_driver_ids, + .driver = { + .name = "spi_sh_msiof", + .of_match_table = of_match_ptr(sh_msiof_match), + }, +}; +module_platform_driver(sh_msiof_spi_drv); + +MODULE_DESCRIPTION("SuperH MSIOF SPI Master Interface Driver"); +MODULE_AUTHOR("Magnus Damm"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:spi_sh_msiof"); diff --git a/drivers/spi/spi-sh-sci.c b/drivers/spi/spi-sh-sci.c new file mode 100644 index 000000000..a9beeeed8 --- /dev/null +++ b/drivers/spi/spi-sh-sci.c @@ -0,0 +1,197 @@ +/* + * SH SCI SPI interface + * + * Copyright (c) 2008 Magnus Damm + * + * Based on S3C24XX GPIO based SPI driver, which is: + * Copyright (c) 2006 Ben Dooks + * Copyright (c) 2006 Simtec Electronics + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + */ + +#include <linux/kernel.h> +#include <linux/delay.h> +#include <linux/spinlock.h> +#include <linux/platform_device.h> + +#include <linux/spi/spi.h> +#include <linux/spi/spi_bitbang.h> +#include <linux/module.h> + +#include <asm/spi.h> +#include <asm/io.h> + +struct sh_sci_spi { + struct spi_bitbang bitbang; + + void __iomem *membase; + unsigned char val; + struct sh_spi_info *info; + struct platform_device *dev; +}; + +#define SCSPTR(sp) (sp->membase + 0x1c) +#define PIN_SCK (1 << 2) +#define PIN_TXD (1 << 0) +#define PIN_RXD PIN_TXD +#define PIN_INIT ((1 << 1) | (1 << 3) | PIN_SCK | PIN_TXD) + +static inline void setbits(struct sh_sci_spi *sp, int bits, int on) +{ + /* + * We are the only user of SCSPTR so no locking is required. + * Reading bit 2 and 0 in SCSPTR gives pin state as input. + * Writing the same bits sets the output value. + * This makes regular read-modify-write difficult so we + * use sp->val to keep track of the latest register value. + */ + + if (on) + sp->val |= bits; + else + sp->val &= ~bits; + + iowrite8(sp->val, SCSPTR(sp)); +} + +static inline void setsck(struct spi_device *dev, int on) +{ + setbits(spi_master_get_devdata(dev->master), PIN_SCK, on); +} + +static inline void setmosi(struct spi_device *dev, int on) +{ + setbits(spi_master_get_devdata(dev->master), PIN_TXD, on); +} + +static inline u32 getmiso(struct spi_device *dev) +{ + struct sh_sci_spi *sp = spi_master_get_devdata(dev->master); + + return (ioread8(SCSPTR(sp)) & PIN_RXD) ? 1 : 0; +} + +#define spidelay(x) ndelay(x) + +#include "spi-bitbang-txrx.h" + +static u32 sh_sci_spi_txrx_mode0(struct spi_device *spi, + unsigned nsecs, u32 word, u8 bits) +{ + return bitbang_txrx_be_cpha0(spi, nsecs, 0, 0, word, bits); +} + +static u32 sh_sci_spi_txrx_mode1(struct spi_device *spi, + unsigned nsecs, u32 word, u8 bits) +{ + return bitbang_txrx_be_cpha1(spi, nsecs, 0, 0, word, bits); +} + +static u32 sh_sci_spi_txrx_mode2(struct spi_device *spi, + unsigned nsecs, u32 word, u8 bits) +{ + return bitbang_txrx_be_cpha0(spi, nsecs, 1, 0, word, bits); +} + +static u32 sh_sci_spi_txrx_mode3(struct spi_device *spi, + unsigned nsecs, u32 word, u8 bits) +{ + return bitbang_txrx_be_cpha1(spi, nsecs, 1, 0, word, bits); +} + +static void sh_sci_spi_chipselect(struct spi_device *dev, int value) +{ + struct sh_sci_spi *sp = spi_master_get_devdata(dev->master); + + if (sp->info->chip_select) + (sp->info->chip_select)(sp->info, dev->chip_select, value); +} + +static int sh_sci_spi_probe(struct platform_device *dev) +{ + struct resource *r; + struct spi_master *master; + struct sh_sci_spi *sp; + int ret; + + master = spi_alloc_master(&dev->dev, sizeof(struct sh_sci_spi)); + if (master == NULL) { + dev_err(&dev->dev, "failed to allocate spi master\n"); + ret = -ENOMEM; + goto err0; + } + + sp = spi_master_get_devdata(master); + + platform_set_drvdata(dev, sp); + sp->info = dev_get_platdata(&dev->dev); + if (!sp->info) { + dev_err(&dev->dev, "platform data is missing\n"); + ret = -ENOENT; + goto err1; + } + + /* setup spi bitbang adaptor */ + sp->bitbang.master = master; + sp->bitbang.master->bus_num = sp->info->bus_num; + sp->bitbang.master->num_chipselect = sp->info->num_chipselect; + sp->bitbang.chipselect = sh_sci_spi_chipselect; + + sp->bitbang.txrx_word[SPI_MODE_0] = sh_sci_spi_txrx_mode0; + sp->bitbang.txrx_word[SPI_MODE_1] = sh_sci_spi_txrx_mode1; + sp->bitbang.txrx_word[SPI_MODE_2] = sh_sci_spi_txrx_mode2; + sp->bitbang.txrx_word[SPI_MODE_3] = sh_sci_spi_txrx_mode3; + + r = platform_get_resource(dev, IORESOURCE_MEM, 0); + if (r == NULL) { + ret = -ENOENT; + goto err1; + } + sp->membase = ioremap(r->start, resource_size(r)); + if (!sp->membase) { + ret = -ENXIO; + goto err1; + } + sp->val = ioread8(SCSPTR(sp)); + setbits(sp, PIN_INIT, 1); + + ret = spi_bitbang_start(&sp->bitbang); + if (!ret) + return 0; + + setbits(sp, PIN_INIT, 0); + iounmap(sp->membase); + err1: + spi_master_put(sp->bitbang.master); + err0: + return ret; +} + +static int sh_sci_spi_remove(struct platform_device *dev) +{ + struct sh_sci_spi *sp = platform_get_drvdata(dev); + + spi_bitbang_stop(&sp->bitbang); + setbits(sp, PIN_INIT, 0); + iounmap(sp->membase); + spi_master_put(sp->bitbang.master); + return 0; +} + +static struct platform_driver sh_sci_spi_drv = { + .probe = sh_sci_spi_probe, + .remove = sh_sci_spi_remove, + .driver = { + .name = "spi_sh_sci", + }, +}; +module_platform_driver(sh_sci_spi_drv); + +MODULE_DESCRIPTION("SH SCI SPI Driver"); +MODULE_AUTHOR("Magnus Damm <damm@opensource.se>"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:spi_sh_sci"); diff --git a/drivers/spi/spi-sh.c b/drivers/spi/spi-sh.c new file mode 100644 index 000000000..502501187 --- /dev/null +++ b/drivers/spi/spi-sh.c @@ -0,0 +1,537 @@ +/* + * SH SPI bus driver + * + * Copyright (C) 2011 Renesas Solutions Corp. + * + * Based on pxa2xx_spi.c: + * Copyright (C) 2005 Stephen Street / StreetFire Sound Labs + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; version 2 of the License. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/sched.h> +#include <linux/errno.h> +#include <linux/timer.h> +#include <linux/delay.h> +#include <linux/list.h> +#include <linux/workqueue.h> +#include <linux/interrupt.h> +#include <linux/platform_device.h> +#include <linux/io.h> +#include <linux/spi/spi.h> + +#define SPI_SH_TBR 0x00 +#define SPI_SH_RBR 0x00 +#define SPI_SH_CR1 0x08 +#define SPI_SH_CR2 0x10 +#define SPI_SH_CR3 0x18 +#define SPI_SH_CR4 0x20 +#define SPI_SH_CR5 0x28 + +/* CR1 */ +#define SPI_SH_TBE 0x80 +#define SPI_SH_TBF 0x40 +#define SPI_SH_RBE 0x20 +#define SPI_SH_RBF 0x10 +#define SPI_SH_PFONRD 0x08 +#define SPI_SH_SSDB 0x04 +#define SPI_SH_SSD 0x02 +#define SPI_SH_SSA 0x01 + +/* CR2 */ +#define SPI_SH_RSTF 0x80 +#define SPI_SH_LOOPBK 0x40 +#define SPI_SH_CPOL 0x20 +#define SPI_SH_CPHA 0x10 +#define SPI_SH_L1M0 0x08 + +/* CR3 */ +#define SPI_SH_MAX_BYTE 0xFF + +/* CR4 */ +#define SPI_SH_TBEI 0x80 +#define SPI_SH_TBFI 0x40 +#define SPI_SH_RBEI 0x20 +#define SPI_SH_RBFI 0x10 +#define SPI_SH_WPABRT 0x04 +#define SPI_SH_SSS 0x01 + +/* CR8 */ +#define SPI_SH_P1L0 0x80 +#define SPI_SH_PP1L0 0x40 +#define SPI_SH_MUXI 0x20 +#define SPI_SH_MUXIRQ 0x10 + +#define SPI_SH_FIFO_SIZE 32 +#define SPI_SH_SEND_TIMEOUT (3 * HZ) +#define SPI_SH_RECEIVE_TIMEOUT (HZ >> 3) + +#undef DEBUG + +struct spi_sh_data { + void __iomem *addr; + int irq; + struct spi_master *master; + struct list_head queue; + struct workqueue_struct *workqueue; + struct work_struct ws; + unsigned long cr1; + wait_queue_head_t wait; + spinlock_t lock; + int width; +}; + +static void spi_sh_write(struct spi_sh_data *ss, unsigned long data, + unsigned long offset) +{ + if (ss->width == 8) + iowrite8(data, ss->addr + (offset >> 2)); + else if (ss->width == 32) + iowrite32(data, ss->addr + offset); +} + +static unsigned long spi_sh_read(struct spi_sh_data *ss, unsigned long offset) +{ + if (ss->width == 8) + return ioread8(ss->addr + (offset >> 2)); + else if (ss->width == 32) + return ioread32(ss->addr + offset); + else + return 0; +} + +static void spi_sh_set_bit(struct spi_sh_data *ss, unsigned long val, + unsigned long offset) +{ + unsigned long tmp; + + tmp = spi_sh_read(ss, offset); + tmp |= val; + spi_sh_write(ss, tmp, offset); +} + +static void spi_sh_clear_bit(struct spi_sh_data *ss, unsigned long val, + unsigned long offset) +{ + unsigned long tmp; + + tmp = spi_sh_read(ss, offset); + tmp &= ~val; + spi_sh_write(ss, tmp, offset); +} + +static void clear_fifo(struct spi_sh_data *ss) +{ + spi_sh_set_bit(ss, SPI_SH_RSTF, SPI_SH_CR2); + spi_sh_clear_bit(ss, SPI_SH_RSTF, SPI_SH_CR2); +} + +static int spi_sh_wait_receive_buffer(struct spi_sh_data *ss) +{ + int timeout = 100000; + + while (spi_sh_read(ss, SPI_SH_CR1) & SPI_SH_RBE) { + udelay(10); + if (timeout-- < 0) + return -ETIMEDOUT; + } + return 0; +} + +static int spi_sh_wait_write_buffer_empty(struct spi_sh_data *ss) +{ + int timeout = 100000; + + while (!(spi_sh_read(ss, SPI_SH_CR1) & SPI_SH_TBE)) { + udelay(10); + if (timeout-- < 0) + return -ETIMEDOUT; + } + return 0; +} + +static int spi_sh_send(struct spi_sh_data *ss, struct spi_message *mesg, + struct spi_transfer *t) +{ + int i, retval = 0; + int remain = t->len; + int cur_len; + unsigned char *data; + long ret; + + if (t->len) + spi_sh_set_bit(ss, SPI_SH_SSA, SPI_SH_CR1); + + data = (unsigned char *)t->tx_buf; + while (remain > 0) { + cur_len = min(SPI_SH_FIFO_SIZE, remain); + for (i = 0; i < cur_len && + !(spi_sh_read(ss, SPI_SH_CR4) & + SPI_SH_WPABRT) && + !(spi_sh_read(ss, SPI_SH_CR1) & SPI_SH_TBF); + i++) + spi_sh_write(ss, (unsigned long)data[i], SPI_SH_TBR); + + if (spi_sh_read(ss, SPI_SH_CR4) & SPI_SH_WPABRT) { + /* Abort SPI operation */ + spi_sh_set_bit(ss, SPI_SH_WPABRT, SPI_SH_CR4); + retval = -EIO; + break; + } + + cur_len = i; + + remain -= cur_len; + data += cur_len; + + if (remain > 0) { + ss->cr1 &= ~SPI_SH_TBE; + spi_sh_set_bit(ss, SPI_SH_TBE, SPI_SH_CR4); + ret = wait_event_interruptible_timeout(ss->wait, + ss->cr1 & SPI_SH_TBE, + SPI_SH_SEND_TIMEOUT); + if (ret == 0 && !(ss->cr1 & SPI_SH_TBE)) { + printk(KERN_ERR "%s: timeout\n", __func__); + return -ETIMEDOUT; + } + } + } + + if (list_is_last(&t->transfer_list, &mesg->transfers)) { + spi_sh_clear_bit(ss, SPI_SH_SSD | SPI_SH_SSDB, SPI_SH_CR1); + spi_sh_set_bit(ss, SPI_SH_SSA, SPI_SH_CR1); + + ss->cr1 &= ~SPI_SH_TBE; + spi_sh_set_bit(ss, SPI_SH_TBE, SPI_SH_CR4); + ret = wait_event_interruptible_timeout(ss->wait, + ss->cr1 & SPI_SH_TBE, + SPI_SH_SEND_TIMEOUT); + if (ret == 0 && (ss->cr1 & SPI_SH_TBE)) { + printk(KERN_ERR "%s: timeout\n", __func__); + return -ETIMEDOUT; + } + } + + return retval; +} + +static int spi_sh_receive(struct spi_sh_data *ss, struct spi_message *mesg, + struct spi_transfer *t) +{ + int i; + int remain = t->len; + int cur_len; + unsigned char *data; + long ret; + + if (t->len > SPI_SH_MAX_BYTE) + spi_sh_write(ss, SPI_SH_MAX_BYTE, SPI_SH_CR3); + else + spi_sh_write(ss, t->len, SPI_SH_CR3); + + spi_sh_clear_bit(ss, SPI_SH_SSD | SPI_SH_SSDB, SPI_SH_CR1); + spi_sh_set_bit(ss, SPI_SH_SSA, SPI_SH_CR1); + + spi_sh_wait_write_buffer_empty(ss); + + data = (unsigned char *)t->rx_buf; + while (remain > 0) { + if (remain >= SPI_SH_FIFO_SIZE) { + ss->cr1 &= ~SPI_SH_RBF; + spi_sh_set_bit(ss, SPI_SH_RBF, SPI_SH_CR4); + ret = wait_event_interruptible_timeout(ss->wait, + ss->cr1 & SPI_SH_RBF, + SPI_SH_RECEIVE_TIMEOUT); + if (ret == 0 && + spi_sh_read(ss, SPI_SH_CR1) & SPI_SH_RBE) { + printk(KERN_ERR "%s: timeout\n", __func__); + return -ETIMEDOUT; + } + } + + cur_len = min(SPI_SH_FIFO_SIZE, remain); + for (i = 0; i < cur_len; i++) { + if (spi_sh_wait_receive_buffer(ss)) + break; + data[i] = (unsigned char)spi_sh_read(ss, SPI_SH_RBR); + } + + remain -= cur_len; + data += cur_len; + } + + /* deassert CS when SPI is receiving. */ + if (t->len > SPI_SH_MAX_BYTE) { + clear_fifo(ss); + spi_sh_write(ss, 1, SPI_SH_CR3); + } else { + spi_sh_write(ss, 0, SPI_SH_CR3); + } + + return 0; +} + +static void spi_sh_work(struct work_struct *work) +{ + struct spi_sh_data *ss = container_of(work, struct spi_sh_data, ws); + struct spi_message *mesg; + struct spi_transfer *t; + unsigned long flags; + int ret; + + pr_debug("%s: enter\n", __func__); + + spin_lock_irqsave(&ss->lock, flags); + while (!list_empty(&ss->queue)) { + mesg = list_entry(ss->queue.next, struct spi_message, queue); + list_del_init(&mesg->queue); + + spin_unlock_irqrestore(&ss->lock, flags); + list_for_each_entry(t, &mesg->transfers, transfer_list) { + pr_debug("tx_buf = %p, rx_buf = %p\n", + t->tx_buf, t->rx_buf); + pr_debug("len = %d, delay_usecs = %d\n", + t->len, t->delay_usecs); + + if (t->tx_buf) { + ret = spi_sh_send(ss, mesg, t); + if (ret < 0) + goto error; + } + if (t->rx_buf) { + ret = spi_sh_receive(ss, mesg, t); + if (ret < 0) + goto error; + } + mesg->actual_length += t->len; + } + spin_lock_irqsave(&ss->lock, flags); + + mesg->status = 0; + if (mesg->complete) + mesg->complete(mesg->context); + } + + clear_fifo(ss); + spi_sh_set_bit(ss, SPI_SH_SSD, SPI_SH_CR1); + udelay(100); + + spi_sh_clear_bit(ss, SPI_SH_SSA | SPI_SH_SSDB | SPI_SH_SSD, + SPI_SH_CR1); + + clear_fifo(ss); + + spin_unlock_irqrestore(&ss->lock, flags); + + return; + + error: + mesg->status = ret; + if (mesg->complete) + mesg->complete(mesg->context); + + spi_sh_clear_bit(ss, SPI_SH_SSA | SPI_SH_SSDB | SPI_SH_SSD, + SPI_SH_CR1); + clear_fifo(ss); + +} + +static int spi_sh_setup(struct spi_device *spi) +{ + struct spi_sh_data *ss = spi_master_get_devdata(spi->master); + + pr_debug("%s: enter\n", __func__); + + spi_sh_write(ss, 0xfe, SPI_SH_CR1); /* SPI sycle stop */ + spi_sh_write(ss, 0x00, SPI_SH_CR1); /* CR1 init */ + spi_sh_write(ss, 0x00, SPI_SH_CR3); /* CR3 init */ + + clear_fifo(ss); + + /* 1/8 clock */ + spi_sh_write(ss, spi_sh_read(ss, SPI_SH_CR2) | 0x07, SPI_SH_CR2); + udelay(10); + + return 0; +} + +static int spi_sh_transfer(struct spi_device *spi, struct spi_message *mesg) +{ + struct spi_sh_data *ss = spi_master_get_devdata(spi->master); + unsigned long flags; + + pr_debug("%s: enter\n", __func__); + pr_debug("\tmode = %02x\n", spi->mode); + + spin_lock_irqsave(&ss->lock, flags); + + mesg->actual_length = 0; + mesg->status = -EINPROGRESS; + + spi_sh_clear_bit(ss, SPI_SH_SSA, SPI_SH_CR1); + + list_add_tail(&mesg->queue, &ss->queue); + queue_work(ss->workqueue, &ss->ws); + + spin_unlock_irqrestore(&ss->lock, flags); + + return 0; +} + +static void spi_sh_cleanup(struct spi_device *spi) +{ + struct spi_sh_data *ss = spi_master_get_devdata(spi->master); + + pr_debug("%s: enter\n", __func__); + + spi_sh_clear_bit(ss, SPI_SH_SSA | SPI_SH_SSDB | SPI_SH_SSD, + SPI_SH_CR1); +} + +static irqreturn_t spi_sh_irq(int irq, void *_ss) +{ + struct spi_sh_data *ss = (struct spi_sh_data *)_ss; + unsigned long cr1; + + cr1 = spi_sh_read(ss, SPI_SH_CR1); + if (cr1 & SPI_SH_TBE) + ss->cr1 |= SPI_SH_TBE; + if (cr1 & SPI_SH_TBF) + ss->cr1 |= SPI_SH_TBF; + if (cr1 & SPI_SH_RBE) + ss->cr1 |= SPI_SH_RBE; + if (cr1 & SPI_SH_RBF) + ss->cr1 |= SPI_SH_RBF; + + if (ss->cr1) { + spi_sh_clear_bit(ss, ss->cr1, SPI_SH_CR4); + wake_up(&ss->wait); + } + + return IRQ_HANDLED; +} + +static int spi_sh_remove(struct platform_device *pdev) +{ + struct spi_sh_data *ss = platform_get_drvdata(pdev); + + spi_unregister_master(ss->master); + destroy_workqueue(ss->workqueue); + free_irq(ss->irq, ss); + + return 0; +} + +static int spi_sh_probe(struct platform_device *pdev) +{ + struct resource *res; + struct spi_master *master; + struct spi_sh_data *ss; + int ret, irq; + + /* get base addr */ + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (unlikely(res == NULL)) { + dev_err(&pdev->dev, "invalid resource\n"); + return -EINVAL; + } + + irq = platform_get_irq(pdev, 0); + if (irq < 0) { + dev_err(&pdev->dev, "platform_get_irq error\n"); + return -ENODEV; + } + + master = spi_alloc_master(&pdev->dev, sizeof(struct spi_sh_data)); + if (master == NULL) { + dev_err(&pdev->dev, "spi_alloc_master error.\n"); + return -ENOMEM; + } + + ss = spi_master_get_devdata(master); + platform_set_drvdata(pdev, ss); + + switch (res->flags & IORESOURCE_MEM_TYPE_MASK) { + case IORESOURCE_MEM_8BIT: + ss->width = 8; + break; + case IORESOURCE_MEM_32BIT: + ss->width = 32; + break; + default: + dev_err(&pdev->dev, "No support width\n"); + ret = -ENODEV; + goto error1; + } + ss->irq = irq; + ss->master = master; + ss->addr = devm_ioremap(&pdev->dev, res->start, resource_size(res)); + if (ss->addr == NULL) { + dev_err(&pdev->dev, "ioremap error.\n"); + ret = -ENOMEM; + goto error1; + } + INIT_LIST_HEAD(&ss->queue); + spin_lock_init(&ss->lock); + INIT_WORK(&ss->ws, spi_sh_work); + init_waitqueue_head(&ss->wait); + ss->workqueue = create_singlethread_workqueue( + dev_name(master->dev.parent)); + if (ss->workqueue == NULL) { + dev_err(&pdev->dev, "create workqueue error\n"); + ret = -EBUSY; + goto error1; + } + + ret = request_irq(irq, spi_sh_irq, 0, "spi_sh", ss); + if (ret < 0) { + dev_err(&pdev->dev, "request_irq error\n"); + goto error2; + } + + master->num_chipselect = 2; + master->bus_num = pdev->id; + master->setup = spi_sh_setup; + master->transfer = spi_sh_transfer; + master->cleanup = spi_sh_cleanup; + + ret = spi_register_master(master); + if (ret < 0) { + printk(KERN_ERR "spi_register_master error.\n"); + goto error3; + } + + return 0; + + error3: + free_irq(irq, ss); + error2: + destroy_workqueue(ss->workqueue); + error1: + spi_master_put(master); + + return ret; +} + +static struct platform_driver spi_sh_driver = { + .probe = spi_sh_probe, + .remove = spi_sh_remove, + .driver = { + .name = "sh_spi", + }, +}; +module_platform_driver(spi_sh_driver); + +MODULE_DESCRIPTION("SH SPI bus driver"); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Yoshihiro Shimoda"); +MODULE_ALIAS("platform:sh_spi"); diff --git a/drivers/spi/spi-sirf.c b/drivers/spi/spi-sirf.c new file mode 100644 index 000000000..f5715c9f6 --- /dev/null +++ b/drivers/spi/spi-sirf.c @@ -0,0 +1,838 @@ +/* + * SPI bus driver for CSR SiRFprimaII + * + * Copyright (c) 2011 Cambridge Silicon Radio Limited, a CSR plc group company. + * + * Licensed under GPLv2 or later. + */ + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/clk.h> +#include <linux/completion.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/of.h> +#include <linux/bitops.h> +#include <linux/err.h> +#include <linux/platform_device.h> +#include <linux/of_gpio.h> +#include <linux/spi/spi.h> +#include <linux/spi/spi_bitbang.h> +#include <linux/dmaengine.h> +#include <linux/dma-direction.h> +#include <linux/dma-mapping.h> +#include <linux/reset.h> + +#define DRIVER_NAME "sirfsoc_spi" + +#define SIRFSOC_SPI_CTRL 0x0000 +#define SIRFSOC_SPI_CMD 0x0004 +#define SIRFSOC_SPI_TX_RX_EN 0x0008 +#define SIRFSOC_SPI_INT_EN 0x000C +#define SIRFSOC_SPI_INT_STATUS 0x0010 +#define SIRFSOC_SPI_TX_DMA_IO_CTRL 0x0100 +#define SIRFSOC_SPI_TX_DMA_IO_LEN 0x0104 +#define SIRFSOC_SPI_TXFIFO_CTRL 0x0108 +#define SIRFSOC_SPI_TXFIFO_LEVEL_CHK 0x010C +#define SIRFSOC_SPI_TXFIFO_OP 0x0110 +#define SIRFSOC_SPI_TXFIFO_STATUS 0x0114 +#define SIRFSOC_SPI_TXFIFO_DATA 0x0118 +#define SIRFSOC_SPI_RX_DMA_IO_CTRL 0x0120 +#define SIRFSOC_SPI_RX_DMA_IO_LEN 0x0124 +#define SIRFSOC_SPI_RXFIFO_CTRL 0x0128 +#define SIRFSOC_SPI_RXFIFO_LEVEL_CHK 0x012C +#define SIRFSOC_SPI_RXFIFO_OP 0x0130 +#define SIRFSOC_SPI_RXFIFO_STATUS 0x0134 +#define SIRFSOC_SPI_RXFIFO_DATA 0x0138 +#define SIRFSOC_SPI_DUMMY_DELAY_CTL 0x0144 + +/* SPI CTRL register defines */ +#define SIRFSOC_SPI_SLV_MODE BIT(16) +#define SIRFSOC_SPI_CMD_MODE BIT(17) +#define SIRFSOC_SPI_CS_IO_OUT BIT(18) +#define SIRFSOC_SPI_CS_IO_MODE BIT(19) +#define SIRFSOC_SPI_CLK_IDLE_STAT BIT(20) +#define SIRFSOC_SPI_CS_IDLE_STAT BIT(21) +#define SIRFSOC_SPI_TRAN_MSB BIT(22) +#define SIRFSOC_SPI_DRV_POS_EDGE BIT(23) +#define SIRFSOC_SPI_CS_HOLD_TIME BIT(24) +#define SIRFSOC_SPI_CLK_SAMPLE_MODE BIT(25) +#define SIRFSOC_SPI_TRAN_DAT_FORMAT_8 (0 << 26) +#define SIRFSOC_SPI_TRAN_DAT_FORMAT_12 (1 << 26) +#define SIRFSOC_SPI_TRAN_DAT_FORMAT_16 (2 << 26) +#define SIRFSOC_SPI_TRAN_DAT_FORMAT_32 (3 << 26) +#define SIRFSOC_SPI_CMD_BYTE_NUM(x) ((x & 3) << 28) +#define SIRFSOC_SPI_ENA_AUTO_CLR BIT(30) +#define SIRFSOC_SPI_MUL_DAT_MODE BIT(31) + +/* Interrupt Enable */ +#define SIRFSOC_SPI_RX_DONE_INT_EN BIT(0) +#define SIRFSOC_SPI_TX_DONE_INT_EN BIT(1) +#define SIRFSOC_SPI_RX_OFLOW_INT_EN BIT(2) +#define SIRFSOC_SPI_TX_UFLOW_INT_EN BIT(3) +#define SIRFSOC_SPI_RX_IO_DMA_INT_EN BIT(4) +#define SIRFSOC_SPI_TX_IO_DMA_INT_EN BIT(5) +#define SIRFSOC_SPI_RXFIFO_FULL_INT_EN BIT(6) +#define SIRFSOC_SPI_TXFIFO_EMPTY_INT_EN BIT(7) +#define SIRFSOC_SPI_RXFIFO_THD_INT_EN BIT(8) +#define SIRFSOC_SPI_TXFIFO_THD_INT_EN BIT(9) +#define SIRFSOC_SPI_FRM_END_INT_EN BIT(10) + +#define SIRFSOC_SPI_INT_MASK_ALL 0x1FFF + +/* Interrupt status */ +#define SIRFSOC_SPI_RX_DONE BIT(0) +#define SIRFSOC_SPI_TX_DONE BIT(1) +#define SIRFSOC_SPI_RX_OFLOW BIT(2) +#define SIRFSOC_SPI_TX_UFLOW BIT(3) +#define SIRFSOC_SPI_RX_IO_DMA BIT(4) +#define SIRFSOC_SPI_RX_FIFO_FULL BIT(6) +#define SIRFSOC_SPI_TXFIFO_EMPTY BIT(7) +#define SIRFSOC_SPI_RXFIFO_THD_REACH BIT(8) +#define SIRFSOC_SPI_TXFIFO_THD_REACH BIT(9) +#define SIRFSOC_SPI_FRM_END BIT(10) + +/* TX RX enable */ +#define SIRFSOC_SPI_RX_EN BIT(0) +#define SIRFSOC_SPI_TX_EN BIT(1) +#define SIRFSOC_SPI_CMD_TX_EN BIT(2) + +#define SIRFSOC_SPI_IO_MODE_SEL BIT(0) +#define SIRFSOC_SPI_RX_DMA_FLUSH BIT(2) + +/* FIFO OPs */ +#define SIRFSOC_SPI_FIFO_RESET BIT(0) +#define SIRFSOC_SPI_FIFO_START BIT(1) + +/* FIFO CTRL */ +#define SIRFSOC_SPI_FIFO_WIDTH_BYTE (0 << 0) +#define SIRFSOC_SPI_FIFO_WIDTH_WORD (1 << 0) +#define SIRFSOC_SPI_FIFO_WIDTH_DWORD (2 << 0) + +/* FIFO Status */ +#define SIRFSOC_SPI_FIFO_LEVEL_MASK 0xFF +#define SIRFSOC_SPI_FIFO_FULL BIT(8) +#define SIRFSOC_SPI_FIFO_EMPTY BIT(9) + +/* 256 bytes rx/tx FIFO */ +#define SIRFSOC_SPI_FIFO_SIZE 256 +#define SIRFSOC_SPI_DAT_FRM_LEN_MAX (64 * 1024) + +#define SIRFSOC_SPI_FIFO_SC(x) ((x) & 0x3F) +#define SIRFSOC_SPI_FIFO_LC(x) (((x) & 0x3F) << 10) +#define SIRFSOC_SPI_FIFO_HC(x) (((x) & 0x3F) << 20) +#define SIRFSOC_SPI_FIFO_THD(x) (((x) & 0xFF) << 2) + +/* + * only if the rx/tx buffer and transfer size are 4-bytes aligned, we use dma + * due to the limitation of dma controller + */ + +#define ALIGNED(x) (!((u32)x & 0x3)) +#define IS_DMA_VALID(x) (x && ALIGNED(x->tx_buf) && ALIGNED(x->rx_buf) && \ + ALIGNED(x->len) && (x->len < 2 * PAGE_SIZE)) + +#define SIRFSOC_MAX_CMD_BYTES 4 +#define SIRFSOC_SPI_DEFAULT_FRQ 1000000 + +struct sirfsoc_spi { + struct spi_bitbang bitbang; + struct completion rx_done; + struct completion tx_done; + + void __iomem *base; + u32 ctrl_freq; /* SPI controller clock speed */ + struct clk *clk; + + /* rx & tx bufs from the spi_transfer */ + const void *tx; + void *rx; + + /* place received word into rx buffer */ + void (*rx_word) (struct sirfsoc_spi *); + /* get word from tx buffer for sending */ + void (*tx_word) (struct sirfsoc_spi *); + + /* number of words left to be tranmitted/received */ + unsigned int left_tx_word; + unsigned int left_rx_word; + + /* rx & tx DMA channels */ + struct dma_chan *rx_chan; + struct dma_chan *tx_chan; + dma_addr_t src_start; + dma_addr_t dst_start; + void *dummypage; + int word_width; /* in bytes */ + + /* + * if tx size is not more than 4 and rx size is NULL, use + * command model + */ + bool tx_by_cmd; + bool hw_cs; +}; + +static void spi_sirfsoc_rx_word_u8(struct sirfsoc_spi *sspi) +{ + u32 data; + u8 *rx = sspi->rx; + + data = readl(sspi->base + SIRFSOC_SPI_RXFIFO_DATA); + + if (rx) { + *rx++ = (u8) data; + sspi->rx = rx; + } + + sspi->left_rx_word--; +} + +static void spi_sirfsoc_tx_word_u8(struct sirfsoc_spi *sspi) +{ + u32 data = 0; + const u8 *tx = sspi->tx; + + if (tx) { + data = *tx++; + sspi->tx = tx; + } + + writel(data, sspi->base + SIRFSOC_SPI_TXFIFO_DATA); + sspi->left_tx_word--; +} + +static void spi_sirfsoc_rx_word_u16(struct sirfsoc_spi *sspi) +{ + u32 data; + u16 *rx = sspi->rx; + + data = readl(sspi->base + SIRFSOC_SPI_RXFIFO_DATA); + + if (rx) { + *rx++ = (u16) data; + sspi->rx = rx; + } + + sspi->left_rx_word--; +} + +static void spi_sirfsoc_tx_word_u16(struct sirfsoc_spi *sspi) +{ + u32 data = 0; + const u16 *tx = sspi->tx; + + if (tx) { + data = *tx++; + sspi->tx = tx; + } + + writel(data, sspi->base + SIRFSOC_SPI_TXFIFO_DATA); + sspi->left_tx_word--; +} + +static void spi_sirfsoc_rx_word_u32(struct sirfsoc_spi *sspi) +{ + u32 data; + u32 *rx = sspi->rx; + + data = readl(sspi->base + SIRFSOC_SPI_RXFIFO_DATA); + + if (rx) { + *rx++ = (u32) data; + sspi->rx = rx; + } + + sspi->left_rx_word--; + +} + +static void spi_sirfsoc_tx_word_u32(struct sirfsoc_spi *sspi) +{ + u32 data = 0; + const u32 *tx = sspi->tx; + + if (tx) { + data = *tx++; + sspi->tx = tx; + } + + writel(data, sspi->base + SIRFSOC_SPI_TXFIFO_DATA); + sspi->left_tx_word--; +} + +static irqreturn_t spi_sirfsoc_irq(int irq, void *dev_id) +{ + struct sirfsoc_spi *sspi = dev_id; + u32 spi_stat = readl(sspi->base + SIRFSOC_SPI_INT_STATUS); + if (sspi->tx_by_cmd && (spi_stat & SIRFSOC_SPI_FRM_END)) { + complete(&sspi->tx_done); + writel(0x0, sspi->base + SIRFSOC_SPI_INT_EN); + writel(SIRFSOC_SPI_INT_MASK_ALL, + sspi->base + SIRFSOC_SPI_INT_STATUS); + return IRQ_HANDLED; + } + + /* Error Conditions */ + if (spi_stat & SIRFSOC_SPI_RX_OFLOW || + spi_stat & SIRFSOC_SPI_TX_UFLOW) { + complete(&sspi->tx_done); + complete(&sspi->rx_done); + writel(0x0, sspi->base + SIRFSOC_SPI_INT_EN); + writel(SIRFSOC_SPI_INT_MASK_ALL, + sspi->base + SIRFSOC_SPI_INT_STATUS); + return IRQ_HANDLED; + } + if (spi_stat & SIRFSOC_SPI_TXFIFO_EMPTY) + complete(&sspi->tx_done); + while (!(readl(sspi->base + SIRFSOC_SPI_INT_STATUS) & + SIRFSOC_SPI_RX_IO_DMA)) + cpu_relax(); + complete(&sspi->rx_done); + writel(0x0, sspi->base + SIRFSOC_SPI_INT_EN); + writel(SIRFSOC_SPI_INT_MASK_ALL, + sspi->base + SIRFSOC_SPI_INT_STATUS); + + return IRQ_HANDLED; +} + +static void spi_sirfsoc_dma_fini_callback(void *data) +{ + struct completion *dma_complete = data; + + complete(dma_complete); +} + +static void spi_sirfsoc_cmd_transfer(struct spi_device *spi, + struct spi_transfer *t) +{ + struct sirfsoc_spi *sspi; + int timeout = t->len * 10; + u32 cmd; + + sspi = spi_master_get_devdata(spi->master); + writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_TXFIFO_OP); + writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_TXFIFO_OP); + memcpy(&cmd, sspi->tx, t->len); + if (sspi->word_width == 1 && !(spi->mode & SPI_LSB_FIRST)) + cmd = cpu_to_be32(cmd) >> + ((SIRFSOC_MAX_CMD_BYTES - t->len) * 8); + if (sspi->word_width == 2 && t->len == 4 && + (!(spi->mode & SPI_LSB_FIRST))) + cmd = ((cmd & 0xffff) << 16) | (cmd >> 16); + writel(cmd, sspi->base + SIRFSOC_SPI_CMD); + writel(SIRFSOC_SPI_FRM_END_INT_EN, + sspi->base + SIRFSOC_SPI_INT_EN); + writel(SIRFSOC_SPI_CMD_TX_EN, + sspi->base + SIRFSOC_SPI_TX_RX_EN); + if (wait_for_completion_timeout(&sspi->tx_done, timeout) == 0) { + dev_err(&spi->dev, "cmd transfer timeout\n"); + return; + } + sspi->left_rx_word -= t->len; +} + +static void spi_sirfsoc_dma_transfer(struct spi_device *spi, + struct spi_transfer *t) +{ + struct sirfsoc_spi *sspi; + struct dma_async_tx_descriptor *rx_desc, *tx_desc; + int timeout = t->len * 10; + + sspi = spi_master_get_devdata(spi->master); + writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_RXFIFO_OP); + writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_TXFIFO_OP); + writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_RXFIFO_OP); + writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_TXFIFO_OP); + writel(0, sspi->base + SIRFSOC_SPI_INT_EN); + writel(SIRFSOC_SPI_INT_MASK_ALL, sspi->base + SIRFSOC_SPI_INT_STATUS); + if (sspi->left_tx_word < SIRFSOC_SPI_DAT_FRM_LEN_MAX) { + writel(readl(sspi->base + SIRFSOC_SPI_CTRL) | + SIRFSOC_SPI_ENA_AUTO_CLR | SIRFSOC_SPI_MUL_DAT_MODE, + sspi->base + SIRFSOC_SPI_CTRL); + writel(sspi->left_tx_word - 1, + sspi->base + SIRFSOC_SPI_TX_DMA_IO_LEN); + writel(sspi->left_tx_word - 1, + sspi->base + SIRFSOC_SPI_RX_DMA_IO_LEN); + } else { + writel(readl(sspi->base + SIRFSOC_SPI_CTRL), + sspi->base + SIRFSOC_SPI_CTRL); + writel(0, sspi->base + SIRFSOC_SPI_TX_DMA_IO_LEN); + writel(0, sspi->base + SIRFSOC_SPI_RX_DMA_IO_LEN); + } + sspi->dst_start = dma_map_single(&spi->dev, sspi->rx, t->len, + (t->tx_buf != t->rx_buf) ? + DMA_FROM_DEVICE : DMA_BIDIRECTIONAL); + rx_desc = dmaengine_prep_slave_single(sspi->rx_chan, + sspi->dst_start, t->len, DMA_DEV_TO_MEM, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + rx_desc->callback = spi_sirfsoc_dma_fini_callback; + rx_desc->callback_param = &sspi->rx_done; + + sspi->src_start = dma_map_single(&spi->dev, (void *)sspi->tx, t->len, + (t->tx_buf != t->rx_buf) ? + DMA_TO_DEVICE : DMA_BIDIRECTIONAL); + tx_desc = dmaengine_prep_slave_single(sspi->tx_chan, + sspi->src_start, t->len, DMA_MEM_TO_DEV, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + tx_desc->callback = spi_sirfsoc_dma_fini_callback; + tx_desc->callback_param = &sspi->tx_done; + + dmaengine_submit(tx_desc); + dmaengine_submit(rx_desc); + dma_async_issue_pending(sspi->tx_chan); + dma_async_issue_pending(sspi->rx_chan); + writel(SIRFSOC_SPI_RX_EN | SIRFSOC_SPI_TX_EN, + sspi->base + SIRFSOC_SPI_TX_RX_EN); + if (wait_for_completion_timeout(&sspi->rx_done, timeout) == 0) { + dev_err(&spi->dev, "transfer timeout\n"); + dmaengine_terminate_all(sspi->rx_chan); + } else + sspi->left_rx_word = 0; + /* + * we only wait tx-done event if transferring by DMA. for PIO, + * we get rx data by writing tx data, so if rx is done, tx has + * done earlier + */ + if (wait_for_completion_timeout(&sspi->tx_done, timeout) == 0) { + dev_err(&spi->dev, "transfer timeout\n"); + dmaengine_terminate_all(sspi->tx_chan); + } + dma_unmap_single(&spi->dev, sspi->src_start, t->len, DMA_TO_DEVICE); + dma_unmap_single(&spi->dev, sspi->dst_start, t->len, DMA_FROM_DEVICE); + /* TX, RX FIFO stop */ + writel(0, sspi->base + SIRFSOC_SPI_RXFIFO_OP); + writel(0, sspi->base + SIRFSOC_SPI_TXFIFO_OP); + if (sspi->left_tx_word >= SIRFSOC_SPI_DAT_FRM_LEN_MAX) + writel(0, sspi->base + SIRFSOC_SPI_TX_RX_EN); +} + +static void spi_sirfsoc_pio_transfer(struct spi_device *spi, + struct spi_transfer *t) +{ + struct sirfsoc_spi *sspi; + int timeout = t->len * 10; + + sspi = spi_master_get_devdata(spi->master); + do { + writel(SIRFSOC_SPI_FIFO_RESET, + sspi->base + SIRFSOC_SPI_RXFIFO_OP); + writel(SIRFSOC_SPI_FIFO_RESET, + sspi->base + SIRFSOC_SPI_TXFIFO_OP); + writel(SIRFSOC_SPI_FIFO_START, + sspi->base + SIRFSOC_SPI_RXFIFO_OP); + writel(SIRFSOC_SPI_FIFO_START, + sspi->base + SIRFSOC_SPI_TXFIFO_OP); + writel(0, sspi->base + SIRFSOC_SPI_INT_EN); + writel(SIRFSOC_SPI_INT_MASK_ALL, + sspi->base + SIRFSOC_SPI_INT_STATUS); + writel(readl(sspi->base + SIRFSOC_SPI_CTRL) | + SIRFSOC_SPI_MUL_DAT_MODE | SIRFSOC_SPI_ENA_AUTO_CLR, + sspi->base + SIRFSOC_SPI_CTRL); + writel(min(sspi->left_tx_word, (u32)(256 / sspi->word_width)) + - 1, sspi->base + SIRFSOC_SPI_TX_DMA_IO_LEN); + writel(min(sspi->left_rx_word, (u32)(256 / sspi->word_width)) + - 1, sspi->base + SIRFSOC_SPI_RX_DMA_IO_LEN); + while (!((readl(sspi->base + SIRFSOC_SPI_TXFIFO_STATUS) + & SIRFSOC_SPI_FIFO_FULL)) && sspi->left_tx_word) + sspi->tx_word(sspi); + writel(SIRFSOC_SPI_TXFIFO_EMPTY_INT_EN | + SIRFSOC_SPI_TX_UFLOW_INT_EN | + SIRFSOC_SPI_RX_OFLOW_INT_EN | + SIRFSOC_SPI_RX_IO_DMA_INT_EN, + sspi->base + SIRFSOC_SPI_INT_EN); + writel(SIRFSOC_SPI_RX_EN | SIRFSOC_SPI_TX_EN, + sspi->base + SIRFSOC_SPI_TX_RX_EN); + if (!wait_for_completion_timeout(&sspi->tx_done, timeout) || + !wait_for_completion_timeout(&sspi->rx_done, timeout)) { + dev_err(&spi->dev, "transfer timeout\n"); + break; + } + while (!((readl(sspi->base + SIRFSOC_SPI_RXFIFO_STATUS) + & SIRFSOC_SPI_FIFO_EMPTY)) && sspi->left_rx_word) + sspi->rx_word(sspi); + writel(0, sspi->base + SIRFSOC_SPI_RXFIFO_OP); + writel(0, sspi->base + SIRFSOC_SPI_TXFIFO_OP); + } while (sspi->left_tx_word != 0 || sspi->left_rx_word != 0); +} + +static int spi_sirfsoc_transfer(struct spi_device *spi, struct spi_transfer *t) +{ + struct sirfsoc_spi *sspi; + sspi = spi_master_get_devdata(spi->master); + + sspi->tx = t->tx_buf ? t->tx_buf : sspi->dummypage; + sspi->rx = t->rx_buf ? t->rx_buf : sspi->dummypage; + sspi->left_tx_word = sspi->left_rx_word = t->len / sspi->word_width; + reinit_completion(&sspi->rx_done); + reinit_completion(&sspi->tx_done); + /* + * in the transfer, if transfer data using command register with rx_buf + * null, just fill command data into command register and wait for its + * completion. + */ + if (sspi->tx_by_cmd) + spi_sirfsoc_cmd_transfer(spi, t); + else if (IS_DMA_VALID(t)) + spi_sirfsoc_dma_transfer(spi, t); + else + spi_sirfsoc_pio_transfer(spi, t); + + return t->len - sspi->left_rx_word * sspi->word_width; +} + +static void spi_sirfsoc_chipselect(struct spi_device *spi, int value) +{ + struct sirfsoc_spi *sspi = spi_master_get_devdata(spi->master); + + if (sspi->hw_cs) { + u32 regval = readl(sspi->base + SIRFSOC_SPI_CTRL); + switch (value) { + case BITBANG_CS_ACTIVE: + if (spi->mode & SPI_CS_HIGH) + regval |= SIRFSOC_SPI_CS_IO_OUT; + else + regval &= ~SIRFSOC_SPI_CS_IO_OUT; + break; + case BITBANG_CS_INACTIVE: + if (spi->mode & SPI_CS_HIGH) + regval &= ~SIRFSOC_SPI_CS_IO_OUT; + else + regval |= SIRFSOC_SPI_CS_IO_OUT; + break; + } + writel(regval, sspi->base + SIRFSOC_SPI_CTRL); + } else { + switch (value) { + case BITBANG_CS_ACTIVE: + gpio_direction_output(spi->cs_gpio, + spi->mode & SPI_CS_HIGH ? 1 : 0); + break; + case BITBANG_CS_INACTIVE: + gpio_direction_output(spi->cs_gpio, + spi->mode & SPI_CS_HIGH ? 0 : 1); + break; + } + } +} + +static int +spi_sirfsoc_setup_transfer(struct spi_device *spi, struct spi_transfer *t) +{ + struct sirfsoc_spi *sspi; + u8 bits_per_word = 0; + int hz = 0; + u32 regval; + u32 txfifo_ctrl, rxfifo_ctrl; + u32 fifo_size = SIRFSOC_SPI_FIFO_SIZE / 4; + + sspi = spi_master_get_devdata(spi->master); + + bits_per_word = (t) ? t->bits_per_word : spi->bits_per_word; + hz = t && t->speed_hz ? t->speed_hz : spi->max_speed_hz; + + regval = (sspi->ctrl_freq / (2 * hz)) - 1; + if (regval > 0xFFFF || regval < 0) { + dev_err(&spi->dev, "Speed %d not supported\n", hz); + return -EINVAL; + } + + switch (bits_per_word) { + case 8: + regval |= SIRFSOC_SPI_TRAN_DAT_FORMAT_8; + sspi->rx_word = spi_sirfsoc_rx_word_u8; + sspi->tx_word = spi_sirfsoc_tx_word_u8; + break; + case 12: + case 16: + regval |= (bits_per_word == 12) ? + SIRFSOC_SPI_TRAN_DAT_FORMAT_12 : + SIRFSOC_SPI_TRAN_DAT_FORMAT_16; + sspi->rx_word = spi_sirfsoc_rx_word_u16; + sspi->tx_word = spi_sirfsoc_tx_word_u16; + break; + case 32: + regval |= SIRFSOC_SPI_TRAN_DAT_FORMAT_32; + sspi->rx_word = spi_sirfsoc_rx_word_u32; + sspi->tx_word = spi_sirfsoc_tx_word_u32; + break; + default: + BUG(); + } + + sspi->word_width = DIV_ROUND_UP(bits_per_word, 8); + txfifo_ctrl = SIRFSOC_SPI_FIFO_THD(SIRFSOC_SPI_FIFO_SIZE / 2) | + (sspi->word_width >> 1); + rxfifo_ctrl = SIRFSOC_SPI_FIFO_THD(SIRFSOC_SPI_FIFO_SIZE / 2) | + (sspi->word_width >> 1); + + if (!(spi->mode & SPI_CS_HIGH)) + regval |= SIRFSOC_SPI_CS_IDLE_STAT; + if (!(spi->mode & SPI_LSB_FIRST)) + regval |= SIRFSOC_SPI_TRAN_MSB; + if (spi->mode & SPI_CPOL) + regval |= SIRFSOC_SPI_CLK_IDLE_STAT; + + /* + * Data should be driven at least 1/2 cycle before the fetch edge + * to make sure that data gets stable at the fetch edge. + */ + if (((spi->mode & SPI_CPOL) && (spi->mode & SPI_CPHA)) || + (!(spi->mode & SPI_CPOL) && !(spi->mode & SPI_CPHA))) + regval &= ~SIRFSOC_SPI_DRV_POS_EDGE; + else + regval |= SIRFSOC_SPI_DRV_POS_EDGE; + + writel(SIRFSOC_SPI_FIFO_SC(fifo_size - 2) | + SIRFSOC_SPI_FIFO_LC(fifo_size / 2) | + SIRFSOC_SPI_FIFO_HC(2), + sspi->base + SIRFSOC_SPI_TXFIFO_LEVEL_CHK); + writel(SIRFSOC_SPI_FIFO_SC(2) | + SIRFSOC_SPI_FIFO_LC(fifo_size / 2) | + SIRFSOC_SPI_FIFO_HC(fifo_size - 2), + sspi->base + SIRFSOC_SPI_RXFIFO_LEVEL_CHK); + writel(txfifo_ctrl, sspi->base + SIRFSOC_SPI_TXFIFO_CTRL); + writel(rxfifo_ctrl, sspi->base + SIRFSOC_SPI_RXFIFO_CTRL); + + if (t && t->tx_buf && !t->rx_buf && (t->len <= SIRFSOC_MAX_CMD_BYTES)) { + regval |= (SIRFSOC_SPI_CMD_BYTE_NUM((t->len - 1)) | + SIRFSOC_SPI_CMD_MODE); + sspi->tx_by_cmd = true; + } else { + regval &= ~SIRFSOC_SPI_CMD_MODE; + sspi->tx_by_cmd = false; + } + /* + * it should never set to hardware cs mode because in hardware cs mode, + * cs signal can't controlled by driver. + */ + regval |= SIRFSOC_SPI_CS_IO_MODE; + writel(regval, sspi->base + SIRFSOC_SPI_CTRL); + + if (IS_DMA_VALID(t)) { + /* Enable DMA mode for RX, TX */ + writel(0, sspi->base + SIRFSOC_SPI_TX_DMA_IO_CTRL); + writel(SIRFSOC_SPI_RX_DMA_FLUSH, + sspi->base + SIRFSOC_SPI_RX_DMA_IO_CTRL); + } else { + /* Enable IO mode for RX, TX */ + writel(SIRFSOC_SPI_IO_MODE_SEL, + sspi->base + SIRFSOC_SPI_TX_DMA_IO_CTRL); + writel(SIRFSOC_SPI_IO_MODE_SEL, + sspi->base + SIRFSOC_SPI_RX_DMA_IO_CTRL); + } + + return 0; +} + +static int spi_sirfsoc_setup(struct spi_device *spi) +{ + struct sirfsoc_spi *sspi; + + sspi = spi_master_get_devdata(spi->master); + + if (spi->cs_gpio == -ENOENT) + sspi->hw_cs = true; + else + sspi->hw_cs = false; + return spi_sirfsoc_setup_transfer(spi, NULL); +} + +static int spi_sirfsoc_probe(struct platform_device *pdev) +{ + struct sirfsoc_spi *sspi; + struct spi_master *master; + struct resource *mem_res; + int irq; + int i, ret; + + ret = device_reset(&pdev->dev); + if (ret) { + dev_err(&pdev->dev, "SPI reset failed!\n"); + return ret; + } + + master = spi_alloc_master(&pdev->dev, sizeof(*sspi)); + if (!master) { + dev_err(&pdev->dev, "Unable to allocate SPI master\n"); + return -ENOMEM; + } + platform_set_drvdata(pdev, master); + sspi = spi_master_get_devdata(master); + + mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + sspi->base = devm_ioremap_resource(&pdev->dev, mem_res); + if (IS_ERR(sspi->base)) { + ret = PTR_ERR(sspi->base); + goto free_master; + } + + irq = platform_get_irq(pdev, 0); + if (irq < 0) { + ret = -ENXIO; + goto free_master; + } + ret = devm_request_irq(&pdev->dev, irq, spi_sirfsoc_irq, 0, + DRIVER_NAME, sspi); + if (ret) + goto free_master; + + sspi->bitbang.master = master; + sspi->bitbang.chipselect = spi_sirfsoc_chipselect; + sspi->bitbang.setup_transfer = spi_sirfsoc_setup_transfer; + sspi->bitbang.txrx_bufs = spi_sirfsoc_transfer; + sspi->bitbang.master->setup = spi_sirfsoc_setup; + master->bus_num = pdev->id; + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST | SPI_CS_HIGH; + master->bits_per_word_mask = SPI_BPW_MASK(8) | SPI_BPW_MASK(12) | + SPI_BPW_MASK(16) | SPI_BPW_MASK(32); + master->max_speed_hz = SIRFSOC_SPI_DEFAULT_FRQ; + sspi->bitbang.master->dev.of_node = pdev->dev.of_node; + + /* request DMA channels */ + sspi->rx_chan = dma_request_slave_channel(&pdev->dev, "rx"); + if (!sspi->rx_chan) { + dev_err(&pdev->dev, "can not allocate rx dma channel\n"); + ret = -ENODEV; + goto free_master; + } + sspi->tx_chan = dma_request_slave_channel(&pdev->dev, "tx"); + if (!sspi->tx_chan) { + dev_err(&pdev->dev, "can not allocate tx dma channel\n"); + ret = -ENODEV; + goto free_rx_dma; + } + + sspi->clk = clk_get(&pdev->dev, NULL); + if (IS_ERR(sspi->clk)) { + ret = PTR_ERR(sspi->clk); + goto free_tx_dma; + } + clk_prepare_enable(sspi->clk); + sspi->ctrl_freq = clk_get_rate(sspi->clk); + + init_completion(&sspi->rx_done); + init_completion(&sspi->tx_done); + + writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_RXFIFO_OP); + writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_TXFIFO_OP); + writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_RXFIFO_OP); + writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_TXFIFO_OP); + /* We are not using dummy delay between command and data */ + writel(0, sspi->base + SIRFSOC_SPI_DUMMY_DELAY_CTL); + + sspi->dummypage = kmalloc(2 * PAGE_SIZE, GFP_KERNEL); + if (!sspi->dummypage) { + ret = -ENOMEM; + goto free_clk; + } + + ret = spi_bitbang_start(&sspi->bitbang); + if (ret) + goto free_dummypage; + for (i = 0; master->cs_gpios && i < master->num_chipselect; i++) { + if (master->cs_gpios[i] == -ENOENT) + continue; + if (!gpio_is_valid(master->cs_gpios[i])) { + dev_err(&pdev->dev, "no valid gpio\n"); + ret = -EINVAL; + goto free_dummypage; + } + ret = devm_gpio_request(&pdev->dev, + master->cs_gpios[i], DRIVER_NAME); + if (ret) { + dev_err(&pdev->dev, "failed to request gpio\n"); + goto free_dummypage; + } + } + dev_info(&pdev->dev, "registerred, bus number = %d\n", master->bus_num); + + return 0; +free_dummypage: + kfree(sspi->dummypage); +free_clk: + clk_disable_unprepare(sspi->clk); + clk_put(sspi->clk); +free_tx_dma: + dma_release_channel(sspi->tx_chan); +free_rx_dma: + dma_release_channel(sspi->rx_chan); +free_master: + spi_master_put(master); + + return ret; +} + +static int spi_sirfsoc_remove(struct platform_device *pdev) +{ + struct spi_master *master; + struct sirfsoc_spi *sspi; + + master = platform_get_drvdata(pdev); + sspi = spi_master_get_devdata(master); + + spi_bitbang_stop(&sspi->bitbang); + kfree(sspi->dummypage); + clk_disable_unprepare(sspi->clk); + clk_put(sspi->clk); + dma_release_channel(sspi->rx_chan); + dma_release_channel(sspi->tx_chan); + spi_master_put(master); + return 0; +} + +#ifdef CONFIG_PM_SLEEP +static int spi_sirfsoc_suspend(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct sirfsoc_spi *sspi = spi_master_get_devdata(master); + int ret; + + ret = spi_master_suspend(master); + if (ret) + return ret; + + clk_disable(sspi->clk); + return 0; +} + +static int spi_sirfsoc_resume(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct sirfsoc_spi *sspi = spi_master_get_devdata(master); + + clk_enable(sspi->clk); + writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_RXFIFO_OP); + writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_TXFIFO_OP); + writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_RXFIFO_OP); + writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_TXFIFO_OP); + + return spi_master_resume(master); +} +#endif + +static SIMPLE_DEV_PM_OPS(spi_sirfsoc_pm_ops, spi_sirfsoc_suspend, + spi_sirfsoc_resume); + +static const struct of_device_id spi_sirfsoc_of_match[] = { + { .compatible = "sirf,prima2-spi", }, + {} +}; +MODULE_DEVICE_TABLE(of, spi_sirfsoc_of_match); + +static struct platform_driver spi_sirfsoc_driver = { + .driver = { + .name = DRIVER_NAME, + .pm = &spi_sirfsoc_pm_ops, + .of_match_table = spi_sirfsoc_of_match, + }, + .probe = spi_sirfsoc_probe, + .remove = spi_sirfsoc_remove, +}; +module_platform_driver(spi_sirfsoc_driver); +MODULE_DESCRIPTION("SiRF SoC SPI master driver"); +MODULE_AUTHOR("Zhiwu Song <Zhiwu.Song@csr.com>"); +MODULE_AUTHOR("Barry Song <Baohua.Song@csr.com>"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/spi/spi-st-ssc4.c b/drivers/spi/spi-st-ssc4.c new file mode 100644 index 000000000..f17c0abe2 --- /dev/null +++ b/drivers/spi/spi-st-ssc4.c @@ -0,0 +1,504 @@ +/* + * Copyright (c) 2008-2014 STMicroelectronics Limited + * + * Author: Angus Clark <Angus.Clark@st.com> + * Patrice Chotard <patrice.chotard@st.com> + * Lee Jones <lee.jones@linaro.org> + * + * SPI master mode controller driver, used in STMicroelectronics devices. + * + * May be copied or modified under the terms of the GNU General Public + * License Version 2.0 only. See linux/COPYING for more information. + */ + +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/pinctrl/consumer.h> +#include <linux/platform_device.h> +#include <linux/of.h> +#include <linux/of_gpio.h> +#include <linux/of_irq.h> +#include <linux/pm_runtime.h> +#include <linux/spi/spi.h> +#include <linux/spi/spi_bitbang.h> + +/* SSC registers */ +#define SSC_BRG 0x000 +#define SSC_TBUF 0x004 +#define SSC_RBUF 0x008 +#define SSC_CTL 0x00C +#define SSC_IEN 0x010 +#define SSC_I2C 0x018 + +/* SSC Control */ +#define SSC_CTL_DATA_WIDTH_9 0x8 +#define SSC_CTL_DATA_WIDTH_MSK 0xf +#define SSC_CTL_BM 0xf +#define SSC_CTL_HB BIT(4) +#define SSC_CTL_PH BIT(5) +#define SSC_CTL_PO BIT(6) +#define SSC_CTL_SR BIT(7) +#define SSC_CTL_MS BIT(8) +#define SSC_CTL_EN BIT(9) +#define SSC_CTL_LPB BIT(10) +#define SSC_CTL_EN_TX_FIFO BIT(11) +#define SSC_CTL_EN_RX_FIFO BIT(12) +#define SSC_CTL_EN_CLST_RX BIT(13) + +/* SSC Interrupt Enable */ +#define SSC_IEN_TEEN BIT(2) + +#define FIFO_SIZE 8 + +struct spi_st { + /* SSC SPI Controller */ + void __iomem *base; + struct clk *clk; + struct device *dev; + + /* SSC SPI current transaction */ + const u8 *tx_ptr; + u8 *rx_ptr; + u16 bytes_per_word; + unsigned int words_remaining; + unsigned int baud; + struct completion done; +}; + +static int spi_st_clk_enable(struct spi_st *spi_st) +{ + /* + * Current platforms use one of the core clocks for SPI and I2C. + * If we attempt to disable the clock, the system will hang. + * + * TODO: Remove this when platform supports power domains. + */ + return 0; + + return clk_prepare_enable(spi_st->clk); +} + +static void spi_st_clk_disable(struct spi_st *spi_st) +{ + /* + * Current platforms use one of the core clocks for SPI and I2C. + * If we attempt to disable the clock, the system will hang. + * + * TODO: Remove this when platform supports power domains. + */ + return; + + clk_disable_unprepare(spi_st->clk); +} + +/* Load the TX FIFO */ +static void ssc_write_tx_fifo(struct spi_st *spi_st) +{ + unsigned int count, i; + uint32_t word = 0; + + if (spi_st->words_remaining > FIFO_SIZE) + count = FIFO_SIZE; + else + count = spi_st->words_remaining; + + for (i = 0; i < count; i++) { + if (spi_st->tx_ptr) { + if (spi_st->bytes_per_word == 1) { + word = *spi_st->tx_ptr++; + } else { + word = *spi_st->tx_ptr++; + word = *spi_st->tx_ptr++ | (word << 8); + } + } + writel_relaxed(word, spi_st->base + SSC_TBUF); + } +} + +/* Read the RX FIFO */ +static void ssc_read_rx_fifo(struct spi_st *spi_st) +{ + unsigned int count, i; + uint32_t word = 0; + + if (spi_st->words_remaining > FIFO_SIZE) + count = FIFO_SIZE; + else + count = spi_st->words_remaining; + + for (i = 0; i < count; i++) { + word = readl_relaxed(spi_st->base + SSC_RBUF); + + if (spi_st->rx_ptr) { + if (spi_st->bytes_per_word == 1) { + *spi_st->rx_ptr++ = (uint8_t)word; + } else { + *spi_st->rx_ptr++ = (word >> 8); + *spi_st->rx_ptr++ = word & 0xff; + } + } + } + spi_st->words_remaining -= count; +} + +static int spi_st_transfer_one(struct spi_master *master, + struct spi_device *spi, struct spi_transfer *t) +{ + struct spi_st *spi_st = spi_master_get_devdata(master); + uint32_t ctl = 0; + + /* Setup transfer */ + spi_st->tx_ptr = t->tx_buf; + spi_st->rx_ptr = t->rx_buf; + + if (spi->bits_per_word > 8) { + /* + * Anything greater than 8 bits-per-word requires 2 + * bytes-per-word in the RX/TX buffers + */ + spi_st->bytes_per_word = 2; + spi_st->words_remaining = t->len / 2; + + } else if (spi->bits_per_word == 8 && !(t->len & 0x1)) { + /* + * If transfer is even-length, and 8 bits-per-word, then + * implement as half-length 16 bits-per-word transfer + */ + spi_st->bytes_per_word = 2; + spi_st->words_remaining = t->len / 2; + + /* Set SSC_CTL to 16 bits-per-word */ + ctl = readl_relaxed(spi_st->base + SSC_CTL); + writel_relaxed((ctl | 0xf), spi_st->base + SSC_CTL); + + readl_relaxed(spi_st->base + SSC_RBUF); + + } else { + spi_st->bytes_per_word = 1; + spi_st->words_remaining = t->len; + } + + reinit_completion(&spi_st->done); + + /* Start transfer by writing to the TX FIFO */ + ssc_write_tx_fifo(spi_st); + writel_relaxed(SSC_IEN_TEEN, spi_st->base + SSC_IEN); + + /* Wait for transfer to complete */ + wait_for_completion(&spi_st->done); + + /* Restore SSC_CTL if necessary */ + if (ctl) + writel_relaxed(ctl, spi_st->base + SSC_CTL); + + spi_finalize_current_transfer(spi->master); + + return t->len; +} + +static void spi_st_cleanup(struct spi_device *spi) +{ + int cs = spi->cs_gpio; + + if (gpio_is_valid(cs)) + devm_gpio_free(&spi->dev, cs); +} + +/* the spi->mode bits understood by this driver: */ +#define MODEBITS (SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST | SPI_LOOP | SPI_CS_HIGH) +static int spi_st_setup(struct spi_device *spi) +{ + struct spi_st *spi_st = spi_master_get_devdata(spi->master); + u32 spi_st_clk, sscbrg, var; + u32 hz = spi->max_speed_hz; + int cs = spi->cs_gpio; + int ret; + + if (!hz) { + dev_err(&spi->dev, "max_speed_hz unspecified\n"); + return -EINVAL; + } + + if (!gpio_is_valid(cs)) { + dev_err(&spi->dev, "%d is not a valid gpio\n", cs); + return -EINVAL; + } + + if (devm_gpio_request(&spi->dev, cs, dev_name(&spi->dev))) { + dev_err(&spi->dev, "could not request gpio:%d\n", cs); + return -EINVAL; + } + + ret = gpio_direction_output(cs, spi->mode & SPI_CS_HIGH); + if (ret) + return ret; + + spi_st_clk = clk_get_rate(spi_st->clk); + + /* Set SSC_BRF */ + sscbrg = spi_st_clk / (2 * hz); + if (sscbrg < 0x07 || sscbrg > BIT(16)) { + dev_err(&spi->dev, + "baudrate %d outside valid range %d\n", sscbrg, hz); + return -EINVAL; + } + + spi_st->baud = spi_st_clk / (2 * sscbrg); + if (sscbrg == BIT(16)) /* 16-bit counter wraps */ + sscbrg = 0x0; + + writel_relaxed(sscbrg, spi_st->base + SSC_BRG); + + dev_dbg(&spi->dev, + "setting baudrate:target= %u hz, actual= %u hz, sscbrg= %u\n", + hz, spi_st->baud, sscbrg); + + /* Set SSC_CTL and enable SSC */ + var = readl_relaxed(spi_st->base + SSC_CTL); + var |= SSC_CTL_MS; + + if (spi->mode & SPI_CPOL) + var |= SSC_CTL_PO; + else + var &= ~SSC_CTL_PO; + + if (spi->mode & SPI_CPHA) + var |= SSC_CTL_PH; + else + var &= ~SSC_CTL_PH; + + if ((spi->mode & SPI_LSB_FIRST) == 0) + var |= SSC_CTL_HB; + else + var &= ~SSC_CTL_HB; + + if (spi->mode & SPI_LOOP) + var |= SSC_CTL_LPB; + else + var &= ~SSC_CTL_LPB; + + var &= ~SSC_CTL_DATA_WIDTH_MSK; + var |= (spi->bits_per_word - 1); + + var |= SSC_CTL_EN_TX_FIFO | SSC_CTL_EN_RX_FIFO; + var |= SSC_CTL_EN; + + writel_relaxed(var, spi_st->base + SSC_CTL); + + /* Clear the status register */ + readl_relaxed(spi_st->base + SSC_RBUF); + + return 0; +} + +/* Interrupt fired when TX shift register becomes empty */ +static irqreturn_t spi_st_irq(int irq, void *dev_id) +{ + struct spi_st *spi_st = (struct spi_st *)dev_id; + + /* Read RX FIFO */ + ssc_read_rx_fifo(spi_st); + + /* Fill TX FIFO */ + if (spi_st->words_remaining) { + ssc_write_tx_fifo(spi_st); + } else { + /* TX/RX complete */ + writel_relaxed(0x0, spi_st->base + SSC_IEN); + /* + * read SSC_IEN to ensure that this bit is set + * before re-enabling interrupt + */ + readl(spi_st->base + SSC_IEN); + complete(&spi_st->done); + } + + return IRQ_HANDLED; +} + +static int spi_st_probe(struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + struct spi_master *master; + struct resource *res; + struct spi_st *spi_st; + int irq, ret = 0; + u32 var; + + master = spi_alloc_master(&pdev->dev, sizeof(*spi_st)); + if (!master) + return -ENOMEM; + + master->dev.of_node = np; + master->mode_bits = MODEBITS; + master->setup = spi_st_setup; + master->cleanup = spi_st_cleanup; + master->transfer_one = spi_st_transfer_one; + master->bits_per_word_mask = SPI_BPW_MASK(8) | SPI_BPW_MASK(16); + master->auto_runtime_pm = true; + master->bus_num = pdev->id; + spi_st = spi_master_get_devdata(master); + + spi_st->clk = devm_clk_get(&pdev->dev, "ssc"); + if (IS_ERR(spi_st->clk)) { + dev_err(&pdev->dev, "Unable to request clock\n"); + return PTR_ERR(spi_st->clk); + } + + ret = spi_st_clk_enable(spi_st); + if (ret) + return ret; + + init_completion(&spi_st->done); + + /* Get resources */ + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + spi_st->base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(spi_st->base)) { + ret = PTR_ERR(spi_st->base); + goto clk_disable; + } + + /* Disable I2C and Reset SSC */ + writel_relaxed(0x0, spi_st->base + SSC_I2C); + var = readw_relaxed(spi_st->base + SSC_CTL); + var |= SSC_CTL_SR; + writel_relaxed(var, spi_st->base + SSC_CTL); + + udelay(1); + var = readl_relaxed(spi_st->base + SSC_CTL); + var &= ~SSC_CTL_SR; + writel_relaxed(var, spi_st->base + SSC_CTL); + + /* Set SSC into slave mode before reconfiguring PIO pins */ + var = readl_relaxed(spi_st->base + SSC_CTL); + var &= ~SSC_CTL_MS; + writel_relaxed(var, spi_st->base + SSC_CTL); + + irq = irq_of_parse_and_map(np, 0); + if (!irq) { + dev_err(&pdev->dev, "IRQ missing or invalid\n"); + ret = -EINVAL; + goto clk_disable; + } + + ret = devm_request_irq(&pdev->dev, irq, spi_st_irq, 0, + pdev->name, spi_st); + if (ret) { + dev_err(&pdev->dev, "Failed to request irq %d\n", irq); + goto clk_disable; + } + + /* by default the device is on */ + pm_runtime_set_active(&pdev->dev); + pm_runtime_enable(&pdev->dev); + + platform_set_drvdata(pdev, master); + + ret = devm_spi_register_master(&pdev->dev, master); + if (ret) { + dev_err(&pdev->dev, "Failed to register master\n"); + goto clk_disable; + } + + return 0; + +clk_disable: + spi_st_clk_disable(spi_st); + + return ret; +} + +static int spi_st_remove(struct platform_device *pdev) +{ + struct spi_master *master = platform_get_drvdata(pdev); + struct spi_st *spi_st = spi_master_get_devdata(master); + + spi_st_clk_disable(spi_st); + + pinctrl_pm_select_sleep_state(&pdev->dev); + + return 0; +} + +#ifdef CONFIG_PM +static int spi_st_runtime_suspend(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct spi_st *spi_st = spi_master_get_devdata(master); + + writel_relaxed(0, spi_st->base + SSC_IEN); + pinctrl_pm_select_sleep_state(dev); + + spi_st_clk_disable(spi_st); + + return 0; +} + +static int spi_st_runtime_resume(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct spi_st *spi_st = spi_master_get_devdata(master); + int ret; + + ret = spi_st_clk_enable(spi_st); + pinctrl_pm_select_default_state(dev); + + return ret; +} +#endif + +#ifdef CONFIG_PM_SLEEP +static int spi_st_suspend(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + int ret; + + ret = spi_master_suspend(master); + if (ret) + return ret; + + return pm_runtime_force_suspend(dev); +} + +static int spi_st_resume(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + int ret; + + ret = spi_master_resume(master); + if (ret) + return ret; + + return pm_runtime_force_resume(dev); +} +#endif + +static const struct dev_pm_ops spi_st_pm = { + SET_SYSTEM_SLEEP_PM_OPS(spi_st_suspend, spi_st_resume) + SET_RUNTIME_PM_OPS(spi_st_runtime_suspend, spi_st_runtime_resume, NULL) +}; + +static const struct of_device_id stm_spi_match[] = { + { .compatible = "st,comms-ssc4-spi", }, + {}, +}; +MODULE_DEVICE_TABLE(of, stm_spi_match); + +static struct platform_driver spi_st_driver = { + .driver = { + .name = "spi-st", + .pm = &spi_st_pm, + .of_match_table = of_match_ptr(stm_spi_match), + }, + .probe = spi_st_probe, + .remove = spi_st_remove, +}; +module_platform_driver(spi_st_driver); + +MODULE_AUTHOR("Patrice Chotard <patrice.chotard@st.com>"); +MODULE_DESCRIPTION("STM SSC SPI driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/spi/spi-sun4i.c b/drivers/spi/spi-sun4i.c new file mode 100644 index 000000000..fbb0a4d74 --- /dev/null +++ b/drivers/spi/spi-sun4i.c @@ -0,0 +1,476 @@ +/* + * Copyright (C) 2012 - 2014 Allwinner Tech + * Pan Nan <pannan@allwinnertech.com> + * + * Copyright (C) 2014 Maxime Ripard + * Maxime Ripard <maxime.ripard@free-electrons.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + */ + +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> + +#include <linux/spi/spi.h> + +#define SUN4I_FIFO_DEPTH 64 + +#define SUN4I_RXDATA_REG 0x00 + +#define SUN4I_TXDATA_REG 0x04 + +#define SUN4I_CTL_REG 0x08 +#define SUN4I_CTL_ENABLE BIT(0) +#define SUN4I_CTL_MASTER BIT(1) +#define SUN4I_CTL_CPHA BIT(2) +#define SUN4I_CTL_CPOL BIT(3) +#define SUN4I_CTL_CS_ACTIVE_LOW BIT(4) +#define SUN4I_CTL_LMTF BIT(6) +#define SUN4I_CTL_TF_RST BIT(8) +#define SUN4I_CTL_RF_RST BIT(9) +#define SUN4I_CTL_XCH BIT(10) +#define SUN4I_CTL_CS_MASK 0x3000 +#define SUN4I_CTL_CS(cs) (((cs) << 12) & SUN4I_CTL_CS_MASK) +#define SUN4I_CTL_DHB BIT(15) +#define SUN4I_CTL_CS_MANUAL BIT(16) +#define SUN4I_CTL_CS_LEVEL BIT(17) +#define SUN4I_CTL_TP BIT(18) + +#define SUN4I_INT_CTL_REG 0x0c +#define SUN4I_INT_CTL_TC BIT(16) + +#define SUN4I_INT_STA_REG 0x10 + +#define SUN4I_DMA_CTL_REG 0x14 + +#define SUN4I_WAIT_REG 0x18 + +#define SUN4I_CLK_CTL_REG 0x1c +#define SUN4I_CLK_CTL_CDR2_MASK 0xff +#define SUN4I_CLK_CTL_CDR2(div) ((div) & SUN4I_CLK_CTL_CDR2_MASK) +#define SUN4I_CLK_CTL_CDR1_MASK 0xf +#define SUN4I_CLK_CTL_CDR1(div) (((div) & SUN4I_CLK_CTL_CDR1_MASK) << 8) +#define SUN4I_CLK_CTL_DRS BIT(12) + +#define SUN4I_BURST_CNT_REG 0x20 +#define SUN4I_BURST_CNT(cnt) ((cnt) & 0xffffff) + +#define SUN4I_XMIT_CNT_REG 0x24 +#define SUN4I_XMIT_CNT(cnt) ((cnt) & 0xffffff) + +#define SUN4I_FIFO_STA_REG 0x28 +#define SUN4I_FIFO_STA_RF_CNT_MASK 0x7f +#define SUN4I_FIFO_STA_RF_CNT_BITS 0 +#define SUN4I_FIFO_STA_TF_CNT_MASK 0x7f +#define SUN4I_FIFO_STA_TF_CNT_BITS 16 + +struct sun4i_spi { + struct spi_master *master; + void __iomem *base_addr; + struct clk *hclk; + struct clk *mclk; + + struct completion done; + + const u8 *tx_buf; + u8 *rx_buf; + int len; +}; + +static inline u32 sun4i_spi_read(struct sun4i_spi *sspi, u32 reg) +{ + return readl(sspi->base_addr + reg); +} + +static inline void sun4i_spi_write(struct sun4i_spi *sspi, u32 reg, u32 value) +{ + writel(value, sspi->base_addr + reg); +} + +static inline void sun4i_spi_drain_fifo(struct sun4i_spi *sspi, int len) +{ + u32 reg, cnt; + u8 byte; + + /* See how much data is available */ + reg = sun4i_spi_read(sspi, SUN4I_FIFO_STA_REG); + reg &= SUN4I_FIFO_STA_RF_CNT_MASK; + cnt = reg >> SUN4I_FIFO_STA_RF_CNT_BITS; + + if (len > cnt) + len = cnt; + + while (len--) { + byte = readb(sspi->base_addr + SUN4I_RXDATA_REG); + if (sspi->rx_buf) + *sspi->rx_buf++ = byte; + } +} + +static inline void sun4i_spi_fill_fifo(struct sun4i_spi *sspi, int len) +{ + u8 byte; + + if (len > sspi->len) + len = sspi->len; + + while (len--) { + byte = sspi->tx_buf ? *sspi->tx_buf++ : 0; + writeb(byte, sspi->base_addr + SUN4I_TXDATA_REG); + sspi->len--; + } +} + +static void sun4i_spi_set_cs(struct spi_device *spi, bool enable) +{ + struct sun4i_spi *sspi = spi_master_get_devdata(spi->master); + u32 reg; + + reg = sun4i_spi_read(sspi, SUN4I_CTL_REG); + + reg &= ~SUN4I_CTL_CS_MASK; + reg |= SUN4I_CTL_CS(spi->chip_select); + + if (enable) + reg |= SUN4I_CTL_CS_LEVEL; + else + reg &= ~SUN4I_CTL_CS_LEVEL; + + /* + * Even though this looks irrelevant since we are supposed to + * be controlling the chip select manually, this bit also + * controls the levels of the chip select for inactive + * devices. + * + * If we don't set it, the chip select level will go low by + * default when the device is idle, which is not really + * expected in the common case where the chip select is active + * low. + */ + if (spi->mode & SPI_CS_HIGH) + reg &= ~SUN4I_CTL_CS_ACTIVE_LOW; + else + reg |= SUN4I_CTL_CS_ACTIVE_LOW; + + sun4i_spi_write(sspi, SUN4I_CTL_REG, reg); +} + +static int sun4i_spi_transfer_one(struct spi_master *master, + struct spi_device *spi, + struct spi_transfer *tfr) +{ + struct sun4i_spi *sspi = spi_master_get_devdata(master); + unsigned int mclk_rate, div, timeout; + unsigned int tx_len = 0; + int ret = 0; + u32 reg; + + /* We don't support transfer larger than the FIFO */ + if (tfr->len > SUN4I_FIFO_DEPTH) + return -EINVAL; + + reinit_completion(&sspi->done); + sspi->tx_buf = tfr->tx_buf; + sspi->rx_buf = tfr->rx_buf; + sspi->len = tfr->len; + + /* Clear pending interrupts */ + sun4i_spi_write(sspi, SUN4I_INT_STA_REG, ~0); + + + reg = sun4i_spi_read(sspi, SUN4I_CTL_REG); + + /* Reset FIFOs */ + sun4i_spi_write(sspi, SUN4I_CTL_REG, + reg | SUN4I_CTL_RF_RST | SUN4I_CTL_TF_RST); + + /* + * Setup the transfer control register: Chip Select, + * polarities, etc. + */ + if (spi->mode & SPI_CPOL) + reg |= SUN4I_CTL_CPOL; + else + reg &= ~SUN4I_CTL_CPOL; + + if (spi->mode & SPI_CPHA) + reg |= SUN4I_CTL_CPHA; + else + reg &= ~SUN4I_CTL_CPHA; + + if (spi->mode & SPI_LSB_FIRST) + reg |= SUN4I_CTL_LMTF; + else + reg &= ~SUN4I_CTL_LMTF; + + + /* + * If it's a TX only transfer, we don't want to fill the RX + * FIFO with bogus data + */ + if (sspi->rx_buf) + reg &= ~SUN4I_CTL_DHB; + else + reg |= SUN4I_CTL_DHB; + + /* We want to control the chip select manually */ + reg |= SUN4I_CTL_CS_MANUAL; + + sun4i_spi_write(sspi, SUN4I_CTL_REG, reg); + + /* Ensure that we have a parent clock fast enough */ + mclk_rate = clk_get_rate(sspi->mclk); + if (mclk_rate < (2 * spi->max_speed_hz)) { + clk_set_rate(sspi->mclk, 2 * spi->max_speed_hz); + mclk_rate = clk_get_rate(sspi->mclk); + } + + /* + * Setup clock divider. + * + * We have two choices there. Either we can use the clock + * divide rate 1, which is calculated thanks to this formula: + * SPI_CLK = MOD_CLK / (2 ^ (cdr + 1)) + * Or we can use CDR2, which is calculated with the formula: + * SPI_CLK = MOD_CLK / (2 * (cdr + 1)) + * Wether we use the former or the latter is set through the + * DRS bit. + * + * First try CDR2, and if we can't reach the expected + * frequency, fall back to CDR1. + */ + div = mclk_rate / (2 * spi->max_speed_hz); + if (div <= (SUN4I_CLK_CTL_CDR2_MASK + 1)) { + if (div > 0) + div--; + + reg = SUN4I_CLK_CTL_CDR2(div) | SUN4I_CLK_CTL_DRS; + } else { + div = ilog2(mclk_rate) - ilog2(spi->max_speed_hz); + reg = SUN4I_CLK_CTL_CDR1(div); + } + + sun4i_spi_write(sspi, SUN4I_CLK_CTL_REG, reg); + + /* Setup the transfer now... */ + if (sspi->tx_buf) + tx_len = tfr->len; + + /* Setup the counters */ + sun4i_spi_write(sspi, SUN4I_BURST_CNT_REG, SUN4I_BURST_CNT(tfr->len)); + sun4i_spi_write(sspi, SUN4I_XMIT_CNT_REG, SUN4I_XMIT_CNT(tx_len)); + + /* Fill the TX FIFO */ + sun4i_spi_fill_fifo(sspi, SUN4I_FIFO_DEPTH); + + /* Enable the interrupts */ + sun4i_spi_write(sspi, SUN4I_INT_CTL_REG, SUN4I_INT_CTL_TC); + + /* Start the transfer */ + reg = sun4i_spi_read(sspi, SUN4I_CTL_REG); + sun4i_spi_write(sspi, SUN4I_CTL_REG, reg | SUN4I_CTL_XCH); + + timeout = wait_for_completion_timeout(&sspi->done, + msecs_to_jiffies(1000)); + if (!timeout) { + ret = -ETIMEDOUT; + goto out; + } + + sun4i_spi_drain_fifo(sspi, SUN4I_FIFO_DEPTH); + +out: + sun4i_spi_write(sspi, SUN4I_INT_CTL_REG, 0); + + return ret; +} + +static irqreturn_t sun4i_spi_handler(int irq, void *dev_id) +{ + struct sun4i_spi *sspi = dev_id; + u32 status = sun4i_spi_read(sspi, SUN4I_INT_STA_REG); + + /* Transfer complete */ + if (status & SUN4I_INT_CTL_TC) { + sun4i_spi_write(sspi, SUN4I_INT_STA_REG, SUN4I_INT_CTL_TC); + complete(&sspi->done); + return IRQ_HANDLED; + } + + return IRQ_NONE; +} + +static int sun4i_spi_runtime_resume(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct sun4i_spi *sspi = spi_master_get_devdata(master); + int ret; + + ret = clk_prepare_enable(sspi->hclk); + if (ret) { + dev_err(dev, "Couldn't enable AHB clock\n"); + goto out; + } + + ret = clk_prepare_enable(sspi->mclk); + if (ret) { + dev_err(dev, "Couldn't enable module clock\n"); + goto err; + } + + sun4i_spi_write(sspi, SUN4I_CTL_REG, + SUN4I_CTL_ENABLE | SUN4I_CTL_MASTER | SUN4I_CTL_TP); + + return 0; + +err: + clk_disable_unprepare(sspi->hclk); +out: + return ret; +} + +static int sun4i_spi_runtime_suspend(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct sun4i_spi *sspi = spi_master_get_devdata(master); + + clk_disable_unprepare(sspi->mclk); + clk_disable_unprepare(sspi->hclk); + + return 0; +} + +static int sun4i_spi_probe(struct platform_device *pdev) +{ + struct spi_master *master; + struct sun4i_spi *sspi; + struct resource *res; + int ret = 0, irq; + + master = spi_alloc_master(&pdev->dev, sizeof(struct sun4i_spi)); + if (!master) { + dev_err(&pdev->dev, "Unable to allocate SPI Master\n"); + return -ENOMEM; + } + + platform_set_drvdata(pdev, master); + sspi = spi_master_get_devdata(master); + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + sspi->base_addr = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(sspi->base_addr)) { + ret = PTR_ERR(sspi->base_addr); + goto err_free_master; + } + + irq = platform_get_irq(pdev, 0); + if (irq < 0) { + dev_err(&pdev->dev, "No spi IRQ specified\n"); + ret = -ENXIO; + goto err_free_master; + } + + ret = devm_request_irq(&pdev->dev, irq, sun4i_spi_handler, + 0, "sun4i-spi", sspi); + if (ret) { + dev_err(&pdev->dev, "Cannot request IRQ\n"); + goto err_free_master; + } + + sspi->master = master; + master->set_cs = sun4i_spi_set_cs; + master->transfer_one = sun4i_spi_transfer_one; + master->num_chipselect = 4; + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LSB_FIRST; + master->bits_per_word_mask = SPI_BPW_MASK(8); + master->dev.of_node = pdev->dev.of_node; + master->auto_runtime_pm = true; + + sspi->hclk = devm_clk_get(&pdev->dev, "ahb"); + if (IS_ERR(sspi->hclk)) { + dev_err(&pdev->dev, "Unable to acquire AHB clock\n"); + ret = PTR_ERR(sspi->hclk); + goto err_free_master; + } + + sspi->mclk = devm_clk_get(&pdev->dev, "mod"); + if (IS_ERR(sspi->mclk)) { + dev_err(&pdev->dev, "Unable to acquire module clock\n"); + ret = PTR_ERR(sspi->mclk); + goto err_free_master; + } + + init_completion(&sspi->done); + + /* + * This wake-up/shutdown pattern is to be able to have the + * device woken up, even if runtime_pm is disabled + */ + ret = sun4i_spi_runtime_resume(&pdev->dev); + if (ret) { + dev_err(&pdev->dev, "Couldn't resume the device\n"); + goto err_free_master; + } + + pm_runtime_set_active(&pdev->dev); + pm_runtime_enable(&pdev->dev); + pm_runtime_idle(&pdev->dev); + + ret = devm_spi_register_master(&pdev->dev, master); + if (ret) { + dev_err(&pdev->dev, "cannot register SPI master\n"); + goto err_pm_disable; + } + + return 0; + +err_pm_disable: + pm_runtime_disable(&pdev->dev); + sun4i_spi_runtime_suspend(&pdev->dev); +err_free_master: + spi_master_put(master); + return ret; +} + +static int sun4i_spi_remove(struct platform_device *pdev) +{ + pm_runtime_disable(&pdev->dev); + + return 0; +} + +static const struct of_device_id sun4i_spi_match[] = { + { .compatible = "allwinner,sun4i-a10-spi", }, + {} +}; +MODULE_DEVICE_TABLE(of, sun4i_spi_match); + +static const struct dev_pm_ops sun4i_spi_pm_ops = { + .runtime_resume = sun4i_spi_runtime_resume, + .runtime_suspend = sun4i_spi_runtime_suspend, +}; + +static struct platform_driver sun4i_spi_driver = { + .probe = sun4i_spi_probe, + .remove = sun4i_spi_remove, + .driver = { + .name = "sun4i-spi", + .of_match_table = sun4i_spi_match, + .pm = &sun4i_spi_pm_ops, + }, +}; +module_platform_driver(sun4i_spi_driver); + +MODULE_AUTHOR("Pan Nan <pannan@allwinnertech.com>"); +MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>"); +MODULE_DESCRIPTION("Allwinner A1X/A20 SPI controller driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/spi/spi-sun6i.c b/drivers/spi/spi-sun6i.c new file mode 100644 index 000000000..ac48f5970 --- /dev/null +++ b/drivers/spi/spi-sun6i.c @@ -0,0 +1,482 @@ +/* + * Copyright (C) 2012 - 2014 Allwinner Tech + * Pan Nan <pannan@allwinnertech.com> + * + * Copyright (C) 2014 Maxime Ripard + * Maxime Ripard <maxime.ripard@free-electrons.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + */ + +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/reset.h> + +#include <linux/spi/spi.h> + +#define SUN6I_FIFO_DEPTH 128 + +#define SUN6I_GBL_CTL_REG 0x04 +#define SUN6I_GBL_CTL_BUS_ENABLE BIT(0) +#define SUN6I_GBL_CTL_MASTER BIT(1) +#define SUN6I_GBL_CTL_TP BIT(7) +#define SUN6I_GBL_CTL_RST BIT(31) + +#define SUN6I_TFR_CTL_REG 0x08 +#define SUN6I_TFR_CTL_CPHA BIT(0) +#define SUN6I_TFR_CTL_CPOL BIT(1) +#define SUN6I_TFR_CTL_SPOL BIT(2) +#define SUN6I_TFR_CTL_CS_MASK 0x30 +#define SUN6I_TFR_CTL_CS(cs) (((cs) << 4) & SUN6I_TFR_CTL_CS_MASK) +#define SUN6I_TFR_CTL_CS_MANUAL BIT(6) +#define SUN6I_TFR_CTL_CS_LEVEL BIT(7) +#define SUN6I_TFR_CTL_DHB BIT(8) +#define SUN6I_TFR_CTL_FBS BIT(12) +#define SUN6I_TFR_CTL_XCH BIT(31) + +#define SUN6I_INT_CTL_REG 0x10 +#define SUN6I_INT_CTL_RF_OVF BIT(8) +#define SUN6I_INT_CTL_TC BIT(12) + +#define SUN6I_INT_STA_REG 0x14 + +#define SUN6I_FIFO_CTL_REG 0x18 +#define SUN6I_FIFO_CTL_RF_RST BIT(15) +#define SUN6I_FIFO_CTL_TF_RST BIT(31) + +#define SUN6I_FIFO_STA_REG 0x1c +#define SUN6I_FIFO_STA_RF_CNT_MASK 0x7f +#define SUN6I_FIFO_STA_RF_CNT_BITS 0 +#define SUN6I_FIFO_STA_TF_CNT_MASK 0x7f +#define SUN6I_FIFO_STA_TF_CNT_BITS 16 + +#define SUN6I_CLK_CTL_REG 0x24 +#define SUN6I_CLK_CTL_CDR2_MASK 0xff +#define SUN6I_CLK_CTL_CDR2(div) (((div) & SUN6I_CLK_CTL_CDR2_MASK) << 0) +#define SUN6I_CLK_CTL_CDR1_MASK 0xf +#define SUN6I_CLK_CTL_CDR1(div) (((div) & SUN6I_CLK_CTL_CDR1_MASK) << 8) +#define SUN6I_CLK_CTL_DRS BIT(12) + +#define SUN6I_BURST_CNT_REG 0x30 +#define SUN6I_BURST_CNT(cnt) ((cnt) & 0xffffff) + +#define SUN6I_XMIT_CNT_REG 0x34 +#define SUN6I_XMIT_CNT(cnt) ((cnt) & 0xffffff) + +#define SUN6I_BURST_CTL_CNT_REG 0x38 +#define SUN6I_BURST_CTL_CNT_STC(cnt) ((cnt) & 0xffffff) + +#define SUN6I_TXDATA_REG 0x200 +#define SUN6I_RXDATA_REG 0x300 + +struct sun6i_spi { + struct spi_master *master; + void __iomem *base_addr; + struct clk *hclk; + struct clk *mclk; + struct reset_control *rstc; + + struct completion done; + + const u8 *tx_buf; + u8 *rx_buf; + int len; +}; + +static inline u32 sun6i_spi_read(struct sun6i_spi *sspi, u32 reg) +{ + return readl(sspi->base_addr + reg); +} + +static inline void sun6i_spi_write(struct sun6i_spi *sspi, u32 reg, u32 value) +{ + writel(value, sspi->base_addr + reg); +} + +static inline void sun6i_spi_drain_fifo(struct sun6i_spi *sspi, int len) +{ + u32 reg, cnt; + u8 byte; + + /* See how much data is available */ + reg = sun6i_spi_read(sspi, SUN6I_FIFO_STA_REG); + reg &= SUN6I_FIFO_STA_RF_CNT_MASK; + cnt = reg >> SUN6I_FIFO_STA_RF_CNT_BITS; + + if (len > cnt) + len = cnt; + + while (len--) { + byte = readb(sspi->base_addr + SUN6I_RXDATA_REG); + if (sspi->rx_buf) + *sspi->rx_buf++ = byte; + } +} + +static inline void sun6i_spi_fill_fifo(struct sun6i_spi *sspi, int len) +{ + u8 byte; + + if (len > sspi->len) + len = sspi->len; + + while (len--) { + byte = sspi->tx_buf ? *sspi->tx_buf++ : 0; + writeb(byte, sspi->base_addr + SUN6I_TXDATA_REG); + sspi->len--; + } +} + +static void sun6i_spi_set_cs(struct spi_device *spi, bool enable) +{ + struct sun6i_spi *sspi = spi_master_get_devdata(spi->master); + u32 reg; + + reg = sun6i_spi_read(sspi, SUN6I_TFR_CTL_REG); + reg &= ~SUN6I_TFR_CTL_CS_MASK; + reg |= SUN6I_TFR_CTL_CS(spi->chip_select); + + if (enable) + reg |= SUN6I_TFR_CTL_CS_LEVEL; + else + reg &= ~SUN6I_TFR_CTL_CS_LEVEL; + + sun6i_spi_write(sspi, SUN6I_TFR_CTL_REG, reg); +} + + +static int sun6i_spi_transfer_one(struct spi_master *master, + struct spi_device *spi, + struct spi_transfer *tfr) +{ + struct sun6i_spi *sspi = spi_master_get_devdata(master); + unsigned int mclk_rate, div, timeout; + unsigned int tx_len = 0; + int ret = 0; + u32 reg; + + /* We don't support transfer larger than the FIFO */ + if (tfr->len > SUN6I_FIFO_DEPTH) + return -EINVAL; + + reinit_completion(&sspi->done); + sspi->tx_buf = tfr->tx_buf; + sspi->rx_buf = tfr->rx_buf; + sspi->len = tfr->len; + + /* Clear pending interrupts */ + sun6i_spi_write(sspi, SUN6I_INT_STA_REG, ~0); + + /* Reset FIFO */ + sun6i_spi_write(sspi, SUN6I_FIFO_CTL_REG, + SUN6I_FIFO_CTL_RF_RST | SUN6I_FIFO_CTL_TF_RST); + + /* + * Setup the transfer control register: Chip Select, + * polarities, etc. + */ + reg = sun6i_spi_read(sspi, SUN6I_TFR_CTL_REG); + + if (spi->mode & SPI_CPOL) + reg |= SUN6I_TFR_CTL_CPOL; + else + reg &= ~SUN6I_TFR_CTL_CPOL; + + if (spi->mode & SPI_CPHA) + reg |= SUN6I_TFR_CTL_CPHA; + else + reg &= ~SUN6I_TFR_CTL_CPHA; + + if (spi->mode & SPI_LSB_FIRST) + reg |= SUN6I_TFR_CTL_FBS; + else + reg &= ~SUN6I_TFR_CTL_FBS; + + /* + * If it's a TX only transfer, we don't want to fill the RX + * FIFO with bogus data + */ + if (sspi->rx_buf) + reg &= ~SUN6I_TFR_CTL_DHB; + else + reg |= SUN6I_TFR_CTL_DHB; + + /* We want to control the chip select manually */ + reg |= SUN6I_TFR_CTL_CS_MANUAL; + + sun6i_spi_write(sspi, SUN6I_TFR_CTL_REG, reg); + + /* Ensure that we have a parent clock fast enough */ + mclk_rate = clk_get_rate(sspi->mclk); + if (mclk_rate < (2 * spi->max_speed_hz)) { + clk_set_rate(sspi->mclk, 2 * spi->max_speed_hz); + mclk_rate = clk_get_rate(sspi->mclk); + } + + /* + * Setup clock divider. + * + * We have two choices there. Either we can use the clock + * divide rate 1, which is calculated thanks to this formula: + * SPI_CLK = MOD_CLK / (2 ^ cdr) + * Or we can use CDR2, which is calculated with the formula: + * SPI_CLK = MOD_CLK / (2 * (cdr + 1)) + * Wether we use the former or the latter is set through the + * DRS bit. + * + * First try CDR2, and if we can't reach the expected + * frequency, fall back to CDR1. + */ + div = mclk_rate / (2 * spi->max_speed_hz); + if (div <= (SUN6I_CLK_CTL_CDR2_MASK + 1)) { + if (div > 0) + div--; + + reg = SUN6I_CLK_CTL_CDR2(div) | SUN6I_CLK_CTL_DRS; + } else { + div = ilog2(mclk_rate) - ilog2(spi->max_speed_hz); + reg = SUN6I_CLK_CTL_CDR1(div); + } + + sun6i_spi_write(sspi, SUN6I_CLK_CTL_REG, reg); + + /* Setup the transfer now... */ + if (sspi->tx_buf) + tx_len = tfr->len; + + /* Setup the counters */ + sun6i_spi_write(sspi, SUN6I_BURST_CNT_REG, SUN6I_BURST_CNT(tfr->len)); + sun6i_spi_write(sspi, SUN6I_XMIT_CNT_REG, SUN6I_XMIT_CNT(tx_len)); + sun6i_spi_write(sspi, SUN6I_BURST_CTL_CNT_REG, + SUN6I_BURST_CTL_CNT_STC(tx_len)); + + /* Fill the TX FIFO */ + sun6i_spi_fill_fifo(sspi, SUN6I_FIFO_DEPTH); + + /* Enable the interrupts */ + sun6i_spi_write(sspi, SUN6I_INT_CTL_REG, SUN6I_INT_CTL_TC); + + /* Start the transfer */ + reg = sun6i_spi_read(sspi, SUN6I_TFR_CTL_REG); + sun6i_spi_write(sspi, SUN6I_TFR_CTL_REG, reg | SUN6I_TFR_CTL_XCH); + + timeout = wait_for_completion_timeout(&sspi->done, + msecs_to_jiffies(1000)); + if (!timeout) { + ret = -ETIMEDOUT; + goto out; + } + + sun6i_spi_drain_fifo(sspi, SUN6I_FIFO_DEPTH); + +out: + sun6i_spi_write(sspi, SUN6I_INT_CTL_REG, 0); + + return ret; +} + +static irqreturn_t sun6i_spi_handler(int irq, void *dev_id) +{ + struct sun6i_spi *sspi = dev_id; + u32 status = sun6i_spi_read(sspi, SUN6I_INT_STA_REG); + + /* Transfer complete */ + if (status & SUN6I_INT_CTL_TC) { + sun6i_spi_write(sspi, SUN6I_INT_STA_REG, SUN6I_INT_CTL_TC); + complete(&sspi->done); + return IRQ_HANDLED; + } + + return IRQ_NONE; +} + +static int sun6i_spi_runtime_resume(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct sun6i_spi *sspi = spi_master_get_devdata(master); + int ret; + + ret = clk_prepare_enable(sspi->hclk); + if (ret) { + dev_err(dev, "Couldn't enable AHB clock\n"); + goto out; + } + + ret = clk_prepare_enable(sspi->mclk); + if (ret) { + dev_err(dev, "Couldn't enable module clock\n"); + goto err; + } + + ret = reset_control_deassert(sspi->rstc); + if (ret) { + dev_err(dev, "Couldn't deassert the device from reset\n"); + goto err2; + } + + sun6i_spi_write(sspi, SUN6I_GBL_CTL_REG, + SUN6I_GBL_CTL_BUS_ENABLE | SUN6I_GBL_CTL_MASTER | SUN6I_GBL_CTL_TP); + + return 0; + +err2: + clk_disable_unprepare(sspi->mclk); +err: + clk_disable_unprepare(sspi->hclk); +out: + return ret; +} + +static int sun6i_spi_runtime_suspend(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct sun6i_spi *sspi = spi_master_get_devdata(master); + + reset_control_assert(sspi->rstc); + clk_disable_unprepare(sspi->mclk); + clk_disable_unprepare(sspi->hclk); + + return 0; +} + +static int sun6i_spi_probe(struct platform_device *pdev) +{ + struct spi_master *master; + struct sun6i_spi *sspi; + struct resource *res; + int ret = 0, irq; + + master = spi_alloc_master(&pdev->dev, sizeof(struct sun6i_spi)); + if (!master) { + dev_err(&pdev->dev, "Unable to allocate SPI Master\n"); + return -ENOMEM; + } + + platform_set_drvdata(pdev, master); + sspi = spi_master_get_devdata(master); + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + sspi->base_addr = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(sspi->base_addr)) { + ret = PTR_ERR(sspi->base_addr); + goto err_free_master; + } + + irq = platform_get_irq(pdev, 0); + if (irq < 0) { + dev_err(&pdev->dev, "No spi IRQ specified\n"); + ret = -ENXIO; + goto err_free_master; + } + + ret = devm_request_irq(&pdev->dev, irq, sun6i_spi_handler, + 0, "sun6i-spi", sspi); + if (ret) { + dev_err(&pdev->dev, "Cannot request IRQ\n"); + goto err_free_master; + } + + sspi->master = master; + master->set_cs = sun6i_spi_set_cs; + master->transfer_one = sun6i_spi_transfer_one; + master->num_chipselect = 4; + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LSB_FIRST; + master->bits_per_word_mask = SPI_BPW_MASK(8); + master->dev.of_node = pdev->dev.of_node; + master->auto_runtime_pm = true; + + sspi->hclk = devm_clk_get(&pdev->dev, "ahb"); + if (IS_ERR(sspi->hclk)) { + dev_err(&pdev->dev, "Unable to acquire AHB clock\n"); + ret = PTR_ERR(sspi->hclk); + goto err_free_master; + } + + sspi->mclk = devm_clk_get(&pdev->dev, "mod"); + if (IS_ERR(sspi->mclk)) { + dev_err(&pdev->dev, "Unable to acquire module clock\n"); + ret = PTR_ERR(sspi->mclk); + goto err_free_master; + } + + init_completion(&sspi->done); + + sspi->rstc = devm_reset_control_get(&pdev->dev, NULL); + if (IS_ERR(sspi->rstc)) { + dev_err(&pdev->dev, "Couldn't get reset controller\n"); + ret = PTR_ERR(sspi->rstc); + goto err_free_master; + } + + /* + * This wake-up/shutdown pattern is to be able to have the + * device woken up, even if runtime_pm is disabled + */ + ret = sun6i_spi_runtime_resume(&pdev->dev); + if (ret) { + dev_err(&pdev->dev, "Couldn't resume the device\n"); + goto err_free_master; + } + + pm_runtime_set_active(&pdev->dev); + pm_runtime_enable(&pdev->dev); + pm_runtime_idle(&pdev->dev); + + ret = devm_spi_register_master(&pdev->dev, master); + if (ret) { + dev_err(&pdev->dev, "cannot register SPI master\n"); + goto err_pm_disable; + } + + return 0; + +err_pm_disable: + pm_runtime_disable(&pdev->dev); + sun6i_spi_runtime_suspend(&pdev->dev); +err_free_master: + spi_master_put(master); + return ret; +} + +static int sun6i_spi_remove(struct platform_device *pdev) +{ + pm_runtime_disable(&pdev->dev); + + return 0; +} + +static const struct of_device_id sun6i_spi_match[] = { + { .compatible = "allwinner,sun6i-a31-spi", }, + {} +}; +MODULE_DEVICE_TABLE(of, sun6i_spi_match); + +static const struct dev_pm_ops sun6i_spi_pm_ops = { + .runtime_resume = sun6i_spi_runtime_resume, + .runtime_suspend = sun6i_spi_runtime_suspend, +}; + +static struct platform_driver sun6i_spi_driver = { + .probe = sun6i_spi_probe, + .remove = sun6i_spi_remove, + .driver = { + .name = "sun6i-spi", + .of_match_table = sun6i_spi_match, + .pm = &sun6i_spi_pm_ops, + }, +}; +module_platform_driver(sun6i_spi_driver); + +MODULE_AUTHOR("Pan Nan <pannan@allwinnertech.com>"); +MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>"); +MODULE_DESCRIPTION("Allwinner A31 SPI controller driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/spi/spi-tegra114.c b/drivers/spi/spi-tegra114.c new file mode 100644 index 000000000..73779cecc --- /dev/null +++ b/drivers/spi/spi-tegra114.c @@ -0,0 +1,1237 @@ +/* + * SPI driver for NVIDIA's Tegra114 SPI Controller. + * + * Copyright (c) 2013, NVIDIA CORPORATION. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <linux/clk.h> +#include <linux/completion.h> +#include <linux/delay.h> +#include <linux/dmaengine.h> +#include <linux/dma-mapping.h> +#include <linux/dmapool.h> +#include <linux/err.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/kthread.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/reset.h> +#include <linux/spi/spi.h> + +#define SPI_COMMAND1 0x000 +#define SPI_BIT_LENGTH(x) (((x) & 0x1f) << 0) +#define SPI_PACKED (1 << 5) +#define SPI_TX_EN (1 << 11) +#define SPI_RX_EN (1 << 12) +#define SPI_BOTH_EN_BYTE (1 << 13) +#define SPI_BOTH_EN_BIT (1 << 14) +#define SPI_LSBYTE_FE (1 << 15) +#define SPI_LSBIT_FE (1 << 16) +#define SPI_BIDIROE (1 << 17) +#define SPI_IDLE_SDA_DRIVE_LOW (0 << 18) +#define SPI_IDLE_SDA_DRIVE_HIGH (1 << 18) +#define SPI_IDLE_SDA_PULL_LOW (2 << 18) +#define SPI_IDLE_SDA_PULL_HIGH (3 << 18) +#define SPI_IDLE_SDA_MASK (3 << 18) +#define SPI_CS_SS_VAL (1 << 20) +#define SPI_CS_SW_HW (1 << 21) +/* SPI_CS_POL_INACTIVE bits are default high */ + /* n from 0 to 3 */ +#define SPI_CS_POL_INACTIVE(n) (1 << (22 + (n))) +#define SPI_CS_POL_INACTIVE_MASK (0xF << 22) + +#define SPI_CS_SEL_0 (0 << 26) +#define SPI_CS_SEL_1 (1 << 26) +#define SPI_CS_SEL_2 (2 << 26) +#define SPI_CS_SEL_3 (3 << 26) +#define SPI_CS_SEL_MASK (3 << 26) +#define SPI_CS_SEL(x) (((x) & 0x3) << 26) +#define SPI_CONTROL_MODE_0 (0 << 28) +#define SPI_CONTROL_MODE_1 (1 << 28) +#define SPI_CONTROL_MODE_2 (2 << 28) +#define SPI_CONTROL_MODE_3 (3 << 28) +#define SPI_CONTROL_MODE_MASK (3 << 28) +#define SPI_MODE_SEL(x) (((x) & 0x3) << 28) +#define SPI_M_S (1 << 30) +#define SPI_PIO (1 << 31) + +#define SPI_COMMAND2 0x004 +#define SPI_TX_TAP_DELAY(x) (((x) & 0x3F) << 6) +#define SPI_RX_TAP_DELAY(x) (((x) & 0x3F) << 0) + +#define SPI_CS_TIMING1 0x008 +#define SPI_SETUP_HOLD(setup, hold) (((setup) << 4) | (hold)) +#define SPI_CS_SETUP_HOLD(reg, cs, val) \ + ((((val) & 0xFFu) << ((cs) * 8)) | \ + ((reg) & ~(0xFFu << ((cs) * 8)))) + +#define SPI_CS_TIMING2 0x00C +#define CYCLES_BETWEEN_PACKETS_0(x) (((x) & 0x1F) << 0) +#define CS_ACTIVE_BETWEEN_PACKETS_0 (1 << 5) +#define CYCLES_BETWEEN_PACKETS_1(x) (((x) & 0x1F) << 8) +#define CS_ACTIVE_BETWEEN_PACKETS_1 (1 << 13) +#define CYCLES_BETWEEN_PACKETS_2(x) (((x) & 0x1F) << 16) +#define CS_ACTIVE_BETWEEN_PACKETS_2 (1 << 21) +#define CYCLES_BETWEEN_PACKETS_3(x) (((x) & 0x1F) << 24) +#define CS_ACTIVE_BETWEEN_PACKETS_3 (1 << 29) +#define SPI_SET_CS_ACTIVE_BETWEEN_PACKETS(reg, cs, val) \ + (reg = (((val) & 0x1) << ((cs) * 8 + 5)) | \ + ((reg) & ~(1 << ((cs) * 8 + 5)))) +#define SPI_SET_CYCLES_BETWEEN_PACKETS(reg, cs, val) \ + (reg = (((val) & 0xF) << ((cs) * 8)) | \ + ((reg) & ~(0xF << ((cs) * 8)))) + +#define SPI_TRANS_STATUS 0x010 +#define SPI_BLK_CNT(val) (((val) >> 0) & 0xFFFF) +#define SPI_SLV_IDLE_COUNT(val) (((val) >> 16) & 0xFF) +#define SPI_RDY (1 << 30) + +#define SPI_FIFO_STATUS 0x014 +#define SPI_RX_FIFO_EMPTY (1 << 0) +#define SPI_RX_FIFO_FULL (1 << 1) +#define SPI_TX_FIFO_EMPTY (1 << 2) +#define SPI_TX_FIFO_FULL (1 << 3) +#define SPI_RX_FIFO_UNF (1 << 4) +#define SPI_RX_FIFO_OVF (1 << 5) +#define SPI_TX_FIFO_UNF (1 << 6) +#define SPI_TX_FIFO_OVF (1 << 7) +#define SPI_ERR (1 << 8) +#define SPI_TX_FIFO_FLUSH (1 << 14) +#define SPI_RX_FIFO_FLUSH (1 << 15) +#define SPI_TX_FIFO_EMPTY_COUNT(val) (((val) >> 16) & 0x7F) +#define SPI_RX_FIFO_FULL_COUNT(val) (((val) >> 23) & 0x7F) +#define SPI_FRAME_END (1 << 30) +#define SPI_CS_INACTIVE (1 << 31) + +#define SPI_FIFO_ERROR (SPI_RX_FIFO_UNF | \ + SPI_RX_FIFO_OVF | SPI_TX_FIFO_UNF | SPI_TX_FIFO_OVF) +#define SPI_FIFO_EMPTY (SPI_RX_FIFO_EMPTY | SPI_TX_FIFO_EMPTY) + +#define SPI_TX_DATA 0x018 +#define SPI_RX_DATA 0x01C + +#define SPI_DMA_CTL 0x020 +#define SPI_TX_TRIG_1 (0 << 15) +#define SPI_TX_TRIG_4 (1 << 15) +#define SPI_TX_TRIG_8 (2 << 15) +#define SPI_TX_TRIG_16 (3 << 15) +#define SPI_TX_TRIG_MASK (3 << 15) +#define SPI_RX_TRIG_1 (0 << 19) +#define SPI_RX_TRIG_4 (1 << 19) +#define SPI_RX_TRIG_8 (2 << 19) +#define SPI_RX_TRIG_16 (3 << 19) +#define SPI_RX_TRIG_MASK (3 << 19) +#define SPI_IE_TX (1 << 28) +#define SPI_IE_RX (1 << 29) +#define SPI_CONT (1 << 30) +#define SPI_DMA (1 << 31) +#define SPI_DMA_EN SPI_DMA + +#define SPI_DMA_BLK 0x024 +#define SPI_DMA_BLK_SET(x) (((x) & 0xFFFF) << 0) + +#define SPI_TX_FIFO 0x108 +#define SPI_RX_FIFO 0x188 +#define MAX_CHIP_SELECT 4 +#define SPI_FIFO_DEPTH 64 +#define DATA_DIR_TX (1 << 0) +#define DATA_DIR_RX (1 << 1) + +#define SPI_DMA_TIMEOUT (msecs_to_jiffies(1000)) +#define DEFAULT_SPI_DMA_BUF_LEN (16*1024) +#define TX_FIFO_EMPTY_COUNT_MAX SPI_TX_FIFO_EMPTY_COUNT(0x40) +#define RX_FIFO_FULL_COUNT_ZERO SPI_RX_FIFO_FULL_COUNT(0) +#define MAX_HOLD_CYCLES 16 +#define SPI_DEFAULT_SPEED 25000000 + +struct tegra_spi_data { + struct device *dev; + struct spi_master *master; + spinlock_t lock; + + struct clk *clk; + struct reset_control *rst; + void __iomem *base; + phys_addr_t phys; + unsigned irq; + u32 cur_speed; + + struct spi_device *cur_spi; + struct spi_device *cs_control; + unsigned cur_pos; + unsigned words_per_32bit; + unsigned bytes_per_word; + unsigned curr_dma_words; + unsigned cur_direction; + + unsigned cur_rx_pos; + unsigned cur_tx_pos; + + unsigned dma_buf_size; + unsigned max_buf_size; + bool is_curr_dma_xfer; + + struct completion rx_dma_complete; + struct completion tx_dma_complete; + + u32 tx_status; + u32 rx_status; + u32 status_reg; + bool is_packed; + + u32 command1_reg; + u32 dma_control_reg; + u32 def_command1_reg; + + struct completion xfer_completion; + struct spi_transfer *curr_xfer; + struct dma_chan *rx_dma_chan; + u32 *rx_dma_buf; + dma_addr_t rx_dma_phys; + struct dma_async_tx_descriptor *rx_dma_desc; + + struct dma_chan *tx_dma_chan; + u32 *tx_dma_buf; + dma_addr_t tx_dma_phys; + struct dma_async_tx_descriptor *tx_dma_desc; +}; + +static int tegra_spi_runtime_suspend(struct device *dev); +static int tegra_spi_runtime_resume(struct device *dev); + +static inline u32 tegra_spi_readl(struct tegra_spi_data *tspi, + unsigned long reg) +{ + return readl(tspi->base + reg); +} + +static inline void tegra_spi_writel(struct tegra_spi_data *tspi, + u32 val, unsigned long reg) +{ + writel(val, tspi->base + reg); + + /* Read back register to make sure that register writes completed */ + if (reg != SPI_TX_FIFO) + readl(tspi->base + SPI_COMMAND1); +} + +static void tegra_spi_clear_status(struct tegra_spi_data *tspi) +{ + u32 val; + + /* Write 1 to clear status register */ + val = tegra_spi_readl(tspi, SPI_TRANS_STATUS); + tegra_spi_writel(tspi, val, SPI_TRANS_STATUS); + + /* Clear fifo status error if any */ + val = tegra_spi_readl(tspi, SPI_FIFO_STATUS); + if (val & SPI_ERR) + tegra_spi_writel(tspi, SPI_ERR | SPI_FIFO_ERROR, + SPI_FIFO_STATUS); +} + +static unsigned tegra_spi_calculate_curr_xfer_param( + struct spi_device *spi, struct tegra_spi_data *tspi, + struct spi_transfer *t) +{ + unsigned remain_len = t->len - tspi->cur_pos; + unsigned max_word; + unsigned bits_per_word = t->bits_per_word; + unsigned max_len; + unsigned total_fifo_words; + + tspi->bytes_per_word = DIV_ROUND_UP(bits_per_word, 8); + + if (bits_per_word == 8 || bits_per_word == 16) { + tspi->is_packed = 1; + tspi->words_per_32bit = 32/bits_per_word; + } else { + tspi->is_packed = 0; + tspi->words_per_32bit = 1; + } + + if (tspi->is_packed) { + max_len = min(remain_len, tspi->max_buf_size); + tspi->curr_dma_words = max_len/tspi->bytes_per_word; + total_fifo_words = (max_len + 3) / 4; + } else { + max_word = (remain_len - 1) / tspi->bytes_per_word + 1; + max_word = min(max_word, tspi->max_buf_size/4); + tspi->curr_dma_words = max_word; + total_fifo_words = max_word; + } + return total_fifo_words; +} + +static unsigned tegra_spi_fill_tx_fifo_from_client_txbuf( + struct tegra_spi_data *tspi, struct spi_transfer *t) +{ + unsigned nbytes; + unsigned tx_empty_count; + u32 fifo_status; + unsigned max_n_32bit; + unsigned i, count; + unsigned int written_words; + unsigned fifo_words_left; + u8 *tx_buf = (u8 *)t->tx_buf + tspi->cur_tx_pos; + + fifo_status = tegra_spi_readl(tspi, SPI_FIFO_STATUS); + tx_empty_count = SPI_TX_FIFO_EMPTY_COUNT(fifo_status); + + if (tspi->is_packed) { + fifo_words_left = tx_empty_count * tspi->words_per_32bit; + written_words = min(fifo_words_left, tspi->curr_dma_words); + nbytes = written_words * tspi->bytes_per_word; + max_n_32bit = DIV_ROUND_UP(nbytes, 4); + for (count = 0; count < max_n_32bit; count++) { + u32 x = 0; + + for (i = 0; (i < 4) && nbytes; i++, nbytes--) + x |= (u32)(*tx_buf++) << (i * 8); + tegra_spi_writel(tspi, x, SPI_TX_FIFO); + } + } else { + max_n_32bit = min(tspi->curr_dma_words, tx_empty_count); + written_words = max_n_32bit; + nbytes = written_words * tspi->bytes_per_word; + for (count = 0; count < max_n_32bit; count++) { + u32 x = 0; + + for (i = 0; nbytes && (i < tspi->bytes_per_word); + i++, nbytes--) + x |= (u32)(*tx_buf++) << (i * 8); + tegra_spi_writel(tspi, x, SPI_TX_FIFO); + } + } + tspi->cur_tx_pos += written_words * tspi->bytes_per_word; + return written_words; +} + +static unsigned int tegra_spi_read_rx_fifo_to_client_rxbuf( + struct tegra_spi_data *tspi, struct spi_transfer *t) +{ + unsigned rx_full_count; + u32 fifo_status; + unsigned i, count; + unsigned int read_words = 0; + unsigned len; + u8 *rx_buf = (u8 *)t->rx_buf + tspi->cur_rx_pos; + + fifo_status = tegra_spi_readl(tspi, SPI_FIFO_STATUS); + rx_full_count = SPI_RX_FIFO_FULL_COUNT(fifo_status); + if (tspi->is_packed) { + len = tspi->curr_dma_words * tspi->bytes_per_word; + for (count = 0; count < rx_full_count; count++) { + u32 x = tegra_spi_readl(tspi, SPI_RX_FIFO); + + for (i = 0; len && (i < 4); i++, len--) + *rx_buf++ = (x >> i*8) & 0xFF; + } + tspi->cur_rx_pos += tspi->curr_dma_words * tspi->bytes_per_word; + read_words += tspi->curr_dma_words; + } else { + u32 rx_mask = ((u32)1 << t->bits_per_word) - 1; + + for (count = 0; count < rx_full_count; count++) { + u32 x = tegra_spi_readl(tspi, SPI_RX_FIFO) & rx_mask; + + for (i = 0; (i < tspi->bytes_per_word); i++) + *rx_buf++ = (x >> (i*8)) & 0xFF; + } + tspi->cur_rx_pos += rx_full_count * tspi->bytes_per_word; + read_words += rx_full_count; + } + return read_words; +} + +static void tegra_spi_copy_client_txbuf_to_spi_txbuf( + struct tegra_spi_data *tspi, struct spi_transfer *t) +{ + /* Make the dma buffer to read by cpu */ + dma_sync_single_for_cpu(tspi->dev, tspi->tx_dma_phys, + tspi->dma_buf_size, DMA_TO_DEVICE); + + if (tspi->is_packed) { + unsigned len = tspi->curr_dma_words * tspi->bytes_per_word; + + memcpy(tspi->tx_dma_buf, t->tx_buf + tspi->cur_pos, len); + } else { + unsigned int i; + unsigned int count; + u8 *tx_buf = (u8 *)t->tx_buf + tspi->cur_tx_pos; + unsigned consume = tspi->curr_dma_words * tspi->bytes_per_word; + + for (count = 0; count < tspi->curr_dma_words; count++) { + u32 x = 0; + + for (i = 0; consume && (i < tspi->bytes_per_word); + i++, consume--) + x |= (u32)(*tx_buf++) << (i * 8); + tspi->tx_dma_buf[count] = x; + } + } + tspi->cur_tx_pos += tspi->curr_dma_words * tspi->bytes_per_word; + + /* Make the dma buffer to read by dma */ + dma_sync_single_for_device(tspi->dev, tspi->tx_dma_phys, + tspi->dma_buf_size, DMA_TO_DEVICE); +} + +static void tegra_spi_copy_spi_rxbuf_to_client_rxbuf( + struct tegra_spi_data *tspi, struct spi_transfer *t) +{ + /* Make the dma buffer to read by cpu */ + dma_sync_single_for_cpu(tspi->dev, tspi->rx_dma_phys, + tspi->dma_buf_size, DMA_FROM_DEVICE); + + if (tspi->is_packed) { + unsigned len = tspi->curr_dma_words * tspi->bytes_per_word; + + memcpy(t->rx_buf + tspi->cur_rx_pos, tspi->rx_dma_buf, len); + } else { + unsigned int i; + unsigned int count; + unsigned char *rx_buf = t->rx_buf + tspi->cur_rx_pos; + u32 rx_mask = ((u32)1 << t->bits_per_word) - 1; + + for (count = 0; count < tspi->curr_dma_words; count++) { + u32 x = tspi->rx_dma_buf[count] & rx_mask; + + for (i = 0; (i < tspi->bytes_per_word); i++) + *rx_buf++ = (x >> (i*8)) & 0xFF; + } + } + tspi->cur_rx_pos += tspi->curr_dma_words * tspi->bytes_per_word; + + /* Make the dma buffer to read by dma */ + dma_sync_single_for_device(tspi->dev, tspi->rx_dma_phys, + tspi->dma_buf_size, DMA_FROM_DEVICE); +} + +static void tegra_spi_dma_complete(void *args) +{ + struct completion *dma_complete = args; + + complete(dma_complete); +} + +static int tegra_spi_start_tx_dma(struct tegra_spi_data *tspi, int len) +{ + reinit_completion(&tspi->tx_dma_complete); + tspi->tx_dma_desc = dmaengine_prep_slave_single(tspi->tx_dma_chan, + tspi->tx_dma_phys, len, DMA_MEM_TO_DEV, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + if (!tspi->tx_dma_desc) { + dev_err(tspi->dev, "Not able to get desc for Tx\n"); + return -EIO; + } + + tspi->tx_dma_desc->callback = tegra_spi_dma_complete; + tspi->tx_dma_desc->callback_param = &tspi->tx_dma_complete; + + dmaengine_submit(tspi->tx_dma_desc); + dma_async_issue_pending(tspi->tx_dma_chan); + return 0; +} + +static int tegra_spi_start_rx_dma(struct tegra_spi_data *tspi, int len) +{ + reinit_completion(&tspi->rx_dma_complete); + tspi->rx_dma_desc = dmaengine_prep_slave_single(tspi->rx_dma_chan, + tspi->rx_dma_phys, len, DMA_DEV_TO_MEM, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + if (!tspi->rx_dma_desc) { + dev_err(tspi->dev, "Not able to get desc for Rx\n"); + return -EIO; + } + + tspi->rx_dma_desc->callback = tegra_spi_dma_complete; + tspi->rx_dma_desc->callback_param = &tspi->rx_dma_complete; + + dmaengine_submit(tspi->rx_dma_desc); + dma_async_issue_pending(tspi->rx_dma_chan); + return 0; +} + +static int tegra_spi_start_dma_based_transfer( + struct tegra_spi_data *tspi, struct spi_transfer *t) +{ + u32 val; + unsigned int len; + int ret = 0; + u32 status; + + /* Make sure that Rx and Tx fifo are empty */ + status = tegra_spi_readl(tspi, SPI_FIFO_STATUS); + if ((status & SPI_FIFO_EMPTY) != SPI_FIFO_EMPTY) { + dev_err(tspi->dev, "Rx/Tx fifo are not empty status 0x%08x\n", + (unsigned)status); + return -EIO; + } + + val = SPI_DMA_BLK_SET(tspi->curr_dma_words - 1); + tegra_spi_writel(tspi, val, SPI_DMA_BLK); + + if (tspi->is_packed) + len = DIV_ROUND_UP(tspi->curr_dma_words * tspi->bytes_per_word, + 4) * 4; + else + len = tspi->curr_dma_words * 4; + + /* Set attention level based on length of transfer */ + if (len & 0xF) + val |= SPI_TX_TRIG_1 | SPI_RX_TRIG_1; + else if (((len) >> 4) & 0x1) + val |= SPI_TX_TRIG_4 | SPI_RX_TRIG_4; + else + val |= SPI_TX_TRIG_8 | SPI_RX_TRIG_8; + + if (tspi->cur_direction & DATA_DIR_TX) + val |= SPI_IE_TX; + + if (tspi->cur_direction & DATA_DIR_RX) + val |= SPI_IE_RX; + + tegra_spi_writel(tspi, val, SPI_DMA_CTL); + tspi->dma_control_reg = val; + + if (tspi->cur_direction & DATA_DIR_TX) { + tegra_spi_copy_client_txbuf_to_spi_txbuf(tspi, t); + ret = tegra_spi_start_tx_dma(tspi, len); + if (ret < 0) { + dev_err(tspi->dev, + "Starting tx dma failed, err %d\n", ret); + return ret; + } + } + + if (tspi->cur_direction & DATA_DIR_RX) { + /* Make the dma buffer to read by dma */ + dma_sync_single_for_device(tspi->dev, tspi->rx_dma_phys, + tspi->dma_buf_size, DMA_FROM_DEVICE); + + ret = tegra_spi_start_rx_dma(tspi, len); + if (ret < 0) { + dev_err(tspi->dev, + "Starting rx dma failed, err %d\n", ret); + if (tspi->cur_direction & DATA_DIR_TX) + dmaengine_terminate_all(tspi->tx_dma_chan); + return ret; + } + } + tspi->is_curr_dma_xfer = true; + tspi->dma_control_reg = val; + + val |= SPI_DMA_EN; + tegra_spi_writel(tspi, val, SPI_DMA_CTL); + return ret; +} + +static int tegra_spi_start_cpu_based_transfer( + struct tegra_spi_data *tspi, struct spi_transfer *t) +{ + u32 val; + unsigned cur_words; + + if (tspi->cur_direction & DATA_DIR_TX) + cur_words = tegra_spi_fill_tx_fifo_from_client_txbuf(tspi, t); + else + cur_words = tspi->curr_dma_words; + + val = SPI_DMA_BLK_SET(cur_words - 1); + tegra_spi_writel(tspi, val, SPI_DMA_BLK); + + val = 0; + if (tspi->cur_direction & DATA_DIR_TX) + val |= SPI_IE_TX; + + if (tspi->cur_direction & DATA_DIR_RX) + val |= SPI_IE_RX; + + tegra_spi_writel(tspi, val, SPI_DMA_CTL); + tspi->dma_control_reg = val; + + tspi->is_curr_dma_xfer = false; + + val |= SPI_DMA_EN; + tegra_spi_writel(tspi, val, SPI_DMA_CTL); + return 0; +} + +static int tegra_spi_init_dma_param(struct tegra_spi_data *tspi, + bool dma_to_memory) +{ + struct dma_chan *dma_chan; + u32 *dma_buf; + dma_addr_t dma_phys; + int ret; + struct dma_slave_config dma_sconfig; + + dma_chan = dma_request_slave_channel_reason(tspi->dev, + dma_to_memory ? "rx" : "tx"); + if (IS_ERR(dma_chan)) { + ret = PTR_ERR(dma_chan); + if (ret != -EPROBE_DEFER) + dev_err(tspi->dev, + "Dma channel is not available: %d\n", ret); + return ret; + } + + dma_buf = dma_alloc_coherent(tspi->dev, tspi->dma_buf_size, + &dma_phys, GFP_KERNEL); + if (!dma_buf) { + dev_err(tspi->dev, " Not able to allocate the dma buffer\n"); + dma_release_channel(dma_chan); + return -ENOMEM; + } + + if (dma_to_memory) { + dma_sconfig.src_addr = tspi->phys + SPI_RX_FIFO; + dma_sconfig.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; + dma_sconfig.src_maxburst = 0; + } else { + dma_sconfig.dst_addr = tspi->phys + SPI_TX_FIFO; + dma_sconfig.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; + dma_sconfig.dst_maxburst = 0; + } + + ret = dmaengine_slave_config(dma_chan, &dma_sconfig); + if (ret) + goto scrub; + if (dma_to_memory) { + tspi->rx_dma_chan = dma_chan; + tspi->rx_dma_buf = dma_buf; + tspi->rx_dma_phys = dma_phys; + } else { + tspi->tx_dma_chan = dma_chan; + tspi->tx_dma_buf = dma_buf; + tspi->tx_dma_phys = dma_phys; + } + return 0; + +scrub: + dma_free_coherent(tspi->dev, tspi->dma_buf_size, dma_buf, dma_phys); + dma_release_channel(dma_chan); + return ret; +} + +static void tegra_spi_deinit_dma_param(struct tegra_spi_data *tspi, + bool dma_to_memory) +{ + u32 *dma_buf; + dma_addr_t dma_phys; + struct dma_chan *dma_chan; + + if (dma_to_memory) { + dma_buf = tspi->rx_dma_buf; + dma_chan = tspi->rx_dma_chan; + dma_phys = tspi->rx_dma_phys; + tspi->rx_dma_chan = NULL; + tspi->rx_dma_buf = NULL; + } else { + dma_buf = tspi->tx_dma_buf; + dma_chan = tspi->tx_dma_chan; + dma_phys = tspi->tx_dma_phys; + tspi->tx_dma_buf = NULL; + tspi->tx_dma_chan = NULL; + } + if (!dma_chan) + return; + + dma_free_coherent(tspi->dev, tspi->dma_buf_size, dma_buf, dma_phys); + dma_release_channel(dma_chan); +} + +static u32 tegra_spi_setup_transfer_one(struct spi_device *spi, + struct spi_transfer *t, bool is_first_of_msg) +{ + struct tegra_spi_data *tspi = spi_master_get_devdata(spi->master); + u32 speed = t->speed_hz; + u8 bits_per_word = t->bits_per_word; + u32 command1; + int req_mode; + + if (speed != tspi->cur_speed) { + clk_set_rate(tspi->clk, speed); + tspi->cur_speed = speed; + } + + tspi->cur_spi = spi; + tspi->cur_pos = 0; + tspi->cur_rx_pos = 0; + tspi->cur_tx_pos = 0; + tspi->curr_xfer = t; + + if (is_first_of_msg) { + tegra_spi_clear_status(tspi); + + command1 = tspi->def_command1_reg; + command1 |= SPI_BIT_LENGTH(bits_per_word - 1); + + command1 &= ~SPI_CONTROL_MODE_MASK; + req_mode = spi->mode & 0x3; + if (req_mode == SPI_MODE_0) + command1 |= SPI_CONTROL_MODE_0; + else if (req_mode == SPI_MODE_1) + command1 |= SPI_CONTROL_MODE_1; + else if (req_mode == SPI_MODE_2) + command1 |= SPI_CONTROL_MODE_2; + else if (req_mode == SPI_MODE_3) + command1 |= SPI_CONTROL_MODE_3; + + if (tspi->cs_control) { + if (tspi->cs_control != spi) + tegra_spi_writel(tspi, command1, SPI_COMMAND1); + tspi->cs_control = NULL; + } else + tegra_spi_writel(tspi, command1, SPI_COMMAND1); + + command1 |= SPI_CS_SW_HW; + if (spi->mode & SPI_CS_HIGH) + command1 |= SPI_CS_SS_VAL; + else + command1 &= ~SPI_CS_SS_VAL; + + tegra_spi_writel(tspi, 0, SPI_COMMAND2); + } else { + command1 = tspi->command1_reg; + command1 &= ~SPI_BIT_LENGTH(~0); + command1 |= SPI_BIT_LENGTH(bits_per_word - 1); + } + + return command1; +} + +static int tegra_spi_start_transfer_one(struct spi_device *spi, + struct spi_transfer *t, u32 command1) +{ + struct tegra_spi_data *tspi = spi_master_get_devdata(spi->master); + unsigned total_fifo_words; + int ret; + + total_fifo_words = tegra_spi_calculate_curr_xfer_param(spi, tspi, t); + + if (tspi->is_packed) + command1 |= SPI_PACKED; + + command1 &= ~(SPI_CS_SEL_MASK | SPI_TX_EN | SPI_RX_EN); + tspi->cur_direction = 0; + if (t->rx_buf) { + command1 |= SPI_RX_EN; + tspi->cur_direction |= DATA_DIR_RX; + } + if (t->tx_buf) { + command1 |= SPI_TX_EN; + tspi->cur_direction |= DATA_DIR_TX; + } + command1 |= SPI_CS_SEL(spi->chip_select); + tegra_spi_writel(tspi, command1, SPI_COMMAND1); + tspi->command1_reg = command1; + + dev_dbg(tspi->dev, "The def 0x%x and written 0x%x\n", + tspi->def_command1_reg, (unsigned)command1); + + if (total_fifo_words > SPI_FIFO_DEPTH) + ret = tegra_spi_start_dma_based_transfer(tspi, t); + else + ret = tegra_spi_start_cpu_based_transfer(tspi, t); + return ret; +} + +static int tegra_spi_setup(struct spi_device *spi) +{ + struct tegra_spi_data *tspi = spi_master_get_devdata(spi->master); + u32 val; + unsigned long flags; + int ret; + + dev_dbg(&spi->dev, "setup %d bpw, %scpol, %scpha, %dHz\n", + spi->bits_per_word, + spi->mode & SPI_CPOL ? "" : "~", + spi->mode & SPI_CPHA ? "" : "~", + spi->max_speed_hz); + + ret = pm_runtime_get_sync(tspi->dev); + if (ret < 0) { + dev_err(tspi->dev, "pm runtime failed, e = %d\n", ret); + return ret; + } + + spin_lock_irqsave(&tspi->lock, flags); + val = tspi->def_command1_reg; + if (spi->mode & SPI_CS_HIGH) + val &= ~SPI_CS_POL_INACTIVE(spi->chip_select); + else + val |= SPI_CS_POL_INACTIVE(spi->chip_select); + tspi->def_command1_reg = val; + tegra_spi_writel(tspi, tspi->def_command1_reg, SPI_COMMAND1); + spin_unlock_irqrestore(&tspi->lock, flags); + + pm_runtime_put(tspi->dev); + return 0; +} + +static void tegra_spi_transfer_delay(int delay) +{ + if (!delay) + return; + + if (delay >= 1000) + mdelay(delay / 1000); + + udelay(delay % 1000); +} + +static int tegra_spi_transfer_one_message(struct spi_master *master, + struct spi_message *msg) +{ + bool is_first_msg = true; + struct tegra_spi_data *tspi = spi_master_get_devdata(master); + struct spi_transfer *xfer; + struct spi_device *spi = msg->spi; + int ret; + bool skip = false; + + msg->status = 0; + msg->actual_length = 0; + + list_for_each_entry(xfer, &msg->transfers, transfer_list) { + u32 cmd1; + + reinit_completion(&tspi->xfer_completion); + + cmd1 = tegra_spi_setup_transfer_one(spi, xfer, is_first_msg); + + if (!xfer->len) { + ret = 0; + skip = true; + goto complete_xfer; + } + + ret = tegra_spi_start_transfer_one(spi, xfer, cmd1); + if (ret < 0) { + dev_err(tspi->dev, + "spi can not start transfer, err %d\n", ret); + goto complete_xfer; + } + + is_first_msg = false; + ret = wait_for_completion_timeout(&tspi->xfer_completion, + SPI_DMA_TIMEOUT); + if (WARN_ON(ret == 0)) { + dev_err(tspi->dev, + "spi trasfer timeout, err %d\n", ret); + ret = -EIO; + goto complete_xfer; + } + + if (tspi->tx_status || tspi->rx_status) { + dev_err(tspi->dev, "Error in Transfer\n"); + ret = -EIO; + goto complete_xfer; + } + msg->actual_length += xfer->len; + +complete_xfer: + if (ret < 0 || skip) { + tegra_spi_writel(tspi, tspi->def_command1_reg, + SPI_COMMAND1); + tegra_spi_transfer_delay(xfer->delay_usecs); + goto exit; + } else if (list_is_last(&xfer->transfer_list, + &msg->transfers)) { + if (xfer->cs_change) + tspi->cs_control = spi; + else { + tegra_spi_writel(tspi, tspi->def_command1_reg, + SPI_COMMAND1); + tegra_spi_transfer_delay(xfer->delay_usecs); + } + } else if (xfer->cs_change) { + tegra_spi_writel(tspi, tspi->def_command1_reg, + SPI_COMMAND1); + tegra_spi_transfer_delay(xfer->delay_usecs); + } + + } + ret = 0; +exit: + msg->status = ret; + spi_finalize_current_message(master); + return ret; +} + +static irqreturn_t handle_cpu_based_xfer(struct tegra_spi_data *tspi) +{ + struct spi_transfer *t = tspi->curr_xfer; + unsigned long flags; + + spin_lock_irqsave(&tspi->lock, flags); + if (tspi->tx_status || tspi->rx_status) { + dev_err(tspi->dev, "CpuXfer ERROR bit set 0x%x\n", + tspi->status_reg); + dev_err(tspi->dev, "CpuXfer 0x%08x:0x%08x\n", + tspi->command1_reg, tspi->dma_control_reg); + reset_control_assert(tspi->rst); + udelay(2); + reset_control_deassert(tspi->rst); + complete(&tspi->xfer_completion); + goto exit; + } + + if (tspi->cur_direction & DATA_DIR_RX) + tegra_spi_read_rx_fifo_to_client_rxbuf(tspi, t); + + if (tspi->cur_direction & DATA_DIR_TX) + tspi->cur_pos = tspi->cur_tx_pos; + else + tspi->cur_pos = tspi->cur_rx_pos; + + if (tspi->cur_pos == t->len) { + complete(&tspi->xfer_completion); + goto exit; + } + + tegra_spi_calculate_curr_xfer_param(tspi->cur_spi, tspi, t); + tegra_spi_start_cpu_based_transfer(tspi, t); +exit: + spin_unlock_irqrestore(&tspi->lock, flags); + return IRQ_HANDLED; +} + +static irqreturn_t handle_dma_based_xfer(struct tegra_spi_data *tspi) +{ + struct spi_transfer *t = tspi->curr_xfer; + long wait_status; + int err = 0; + unsigned total_fifo_words; + unsigned long flags; + + /* Abort dmas if any error */ + if (tspi->cur_direction & DATA_DIR_TX) { + if (tspi->tx_status) { + dmaengine_terminate_all(tspi->tx_dma_chan); + err += 1; + } else { + wait_status = wait_for_completion_interruptible_timeout( + &tspi->tx_dma_complete, SPI_DMA_TIMEOUT); + if (wait_status <= 0) { + dmaengine_terminate_all(tspi->tx_dma_chan); + dev_err(tspi->dev, "TxDma Xfer failed\n"); + err += 1; + } + } + } + + if (tspi->cur_direction & DATA_DIR_RX) { + if (tspi->rx_status) { + dmaengine_terminate_all(tspi->rx_dma_chan); + err += 2; + } else { + wait_status = wait_for_completion_interruptible_timeout( + &tspi->rx_dma_complete, SPI_DMA_TIMEOUT); + if (wait_status <= 0) { + dmaengine_terminate_all(tspi->rx_dma_chan); + dev_err(tspi->dev, "RxDma Xfer failed\n"); + err += 2; + } + } + } + + spin_lock_irqsave(&tspi->lock, flags); + if (err) { + dev_err(tspi->dev, "DmaXfer: ERROR bit set 0x%x\n", + tspi->status_reg); + dev_err(tspi->dev, "DmaXfer 0x%08x:0x%08x\n", + tspi->command1_reg, tspi->dma_control_reg); + reset_control_assert(tspi->rst); + udelay(2); + reset_control_deassert(tspi->rst); + complete(&tspi->xfer_completion); + spin_unlock_irqrestore(&tspi->lock, flags); + return IRQ_HANDLED; + } + + if (tspi->cur_direction & DATA_DIR_RX) + tegra_spi_copy_spi_rxbuf_to_client_rxbuf(tspi, t); + + if (tspi->cur_direction & DATA_DIR_TX) + tspi->cur_pos = tspi->cur_tx_pos; + else + tspi->cur_pos = tspi->cur_rx_pos; + + if (tspi->cur_pos == t->len) { + complete(&tspi->xfer_completion); + goto exit; + } + + /* Continue transfer in current message */ + total_fifo_words = tegra_spi_calculate_curr_xfer_param(tspi->cur_spi, + tspi, t); + if (total_fifo_words > SPI_FIFO_DEPTH) + err = tegra_spi_start_dma_based_transfer(tspi, t); + else + err = tegra_spi_start_cpu_based_transfer(tspi, t); + +exit: + spin_unlock_irqrestore(&tspi->lock, flags); + return IRQ_HANDLED; +} + +static irqreturn_t tegra_spi_isr_thread(int irq, void *context_data) +{ + struct tegra_spi_data *tspi = context_data; + + if (!tspi->is_curr_dma_xfer) + return handle_cpu_based_xfer(tspi); + return handle_dma_based_xfer(tspi); +} + +static irqreturn_t tegra_spi_isr(int irq, void *context_data) +{ + struct tegra_spi_data *tspi = context_data; + + tspi->status_reg = tegra_spi_readl(tspi, SPI_FIFO_STATUS); + if (tspi->cur_direction & DATA_DIR_TX) + tspi->tx_status = tspi->status_reg & + (SPI_TX_FIFO_UNF | SPI_TX_FIFO_OVF); + + if (tspi->cur_direction & DATA_DIR_RX) + tspi->rx_status = tspi->status_reg & + (SPI_RX_FIFO_OVF | SPI_RX_FIFO_UNF); + tegra_spi_clear_status(tspi); + + return IRQ_WAKE_THREAD; +} + +static const struct of_device_id tegra_spi_of_match[] = { + { .compatible = "nvidia,tegra114-spi", }, + {} +}; +MODULE_DEVICE_TABLE(of, tegra_spi_of_match); + +static int tegra_spi_probe(struct platform_device *pdev) +{ + struct spi_master *master; + struct tegra_spi_data *tspi; + struct resource *r; + int ret, spi_irq; + + master = spi_alloc_master(&pdev->dev, sizeof(*tspi)); + if (!master) { + dev_err(&pdev->dev, "master allocation failed\n"); + return -ENOMEM; + } + platform_set_drvdata(pdev, master); + tspi = spi_master_get_devdata(master); + + if (of_property_read_u32(pdev->dev.of_node, "spi-max-frequency", + &master->max_speed_hz)) + master->max_speed_hz = 25000000; /* 25MHz */ + + /* the spi->mode bits understood by this driver: */ + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH; + master->setup = tegra_spi_setup; + master->transfer_one_message = tegra_spi_transfer_one_message; + master->num_chipselect = MAX_CHIP_SELECT; + master->auto_runtime_pm = true; + + tspi->master = master; + tspi->dev = &pdev->dev; + spin_lock_init(&tspi->lock); + + r = platform_get_resource(pdev, IORESOURCE_MEM, 0); + tspi->base = devm_ioremap_resource(&pdev->dev, r); + if (IS_ERR(tspi->base)) { + ret = PTR_ERR(tspi->base); + goto exit_free_master; + } + tspi->phys = r->start; + + spi_irq = platform_get_irq(pdev, 0); + tspi->irq = spi_irq; + ret = request_threaded_irq(tspi->irq, tegra_spi_isr, + tegra_spi_isr_thread, IRQF_ONESHOT, + dev_name(&pdev->dev), tspi); + if (ret < 0) { + dev_err(&pdev->dev, "Failed to register ISR for IRQ %d\n", + tspi->irq); + goto exit_free_master; + } + + tspi->clk = devm_clk_get(&pdev->dev, "spi"); + if (IS_ERR(tspi->clk)) { + dev_err(&pdev->dev, "can not get clock\n"); + ret = PTR_ERR(tspi->clk); + goto exit_free_irq; + } + + tspi->rst = devm_reset_control_get(&pdev->dev, "spi"); + if (IS_ERR(tspi->rst)) { + dev_err(&pdev->dev, "can not get reset\n"); + ret = PTR_ERR(tspi->rst); + goto exit_free_irq; + } + + tspi->max_buf_size = SPI_FIFO_DEPTH << 2; + tspi->dma_buf_size = DEFAULT_SPI_DMA_BUF_LEN; + + ret = tegra_spi_init_dma_param(tspi, true); + if (ret < 0) + goto exit_free_irq; + ret = tegra_spi_init_dma_param(tspi, false); + if (ret < 0) + goto exit_rx_dma_free; + tspi->max_buf_size = tspi->dma_buf_size; + init_completion(&tspi->tx_dma_complete); + init_completion(&tspi->rx_dma_complete); + + init_completion(&tspi->xfer_completion); + + pm_runtime_enable(&pdev->dev); + if (!pm_runtime_enabled(&pdev->dev)) { + ret = tegra_spi_runtime_resume(&pdev->dev); + if (ret) + goto exit_pm_disable; + } + + ret = pm_runtime_get_sync(&pdev->dev); + if (ret < 0) { + dev_err(&pdev->dev, "pm runtime get failed, e = %d\n", ret); + goto exit_pm_disable; + } + tspi->def_command1_reg = SPI_M_S; + tegra_spi_writel(tspi, tspi->def_command1_reg, SPI_COMMAND1); + pm_runtime_put(&pdev->dev); + + master->dev.of_node = pdev->dev.of_node; + ret = devm_spi_register_master(&pdev->dev, master); + if (ret < 0) { + dev_err(&pdev->dev, "can not register to master err %d\n", ret); + goto exit_pm_disable; + } + return ret; + +exit_pm_disable: + pm_runtime_disable(&pdev->dev); + if (!pm_runtime_status_suspended(&pdev->dev)) + tegra_spi_runtime_suspend(&pdev->dev); + tegra_spi_deinit_dma_param(tspi, false); +exit_rx_dma_free: + tegra_spi_deinit_dma_param(tspi, true); +exit_free_irq: + free_irq(spi_irq, tspi); +exit_free_master: + spi_master_put(master); + return ret; +} + +static int tegra_spi_remove(struct platform_device *pdev) +{ + struct spi_master *master = platform_get_drvdata(pdev); + struct tegra_spi_data *tspi = spi_master_get_devdata(master); + + free_irq(tspi->irq, tspi); + + if (tspi->tx_dma_chan) + tegra_spi_deinit_dma_param(tspi, false); + + if (tspi->rx_dma_chan) + tegra_spi_deinit_dma_param(tspi, true); + + pm_runtime_disable(&pdev->dev); + if (!pm_runtime_status_suspended(&pdev->dev)) + tegra_spi_runtime_suspend(&pdev->dev); + + return 0; +} + +#ifdef CONFIG_PM_SLEEP +static int tegra_spi_suspend(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + + return spi_master_suspend(master); +} + +static int tegra_spi_resume(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct tegra_spi_data *tspi = spi_master_get_devdata(master); + int ret; + + ret = pm_runtime_get_sync(dev); + if (ret < 0) { + dev_err(dev, "pm runtime failed, e = %d\n", ret); + return ret; + } + tegra_spi_writel(tspi, tspi->command1_reg, SPI_COMMAND1); + pm_runtime_put(dev); + + return spi_master_resume(master); +} +#endif + +static int tegra_spi_runtime_suspend(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct tegra_spi_data *tspi = spi_master_get_devdata(master); + + /* Flush all write which are in PPSB queue by reading back */ + tegra_spi_readl(tspi, SPI_COMMAND1); + + clk_disable_unprepare(tspi->clk); + return 0; +} + +static int tegra_spi_runtime_resume(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct tegra_spi_data *tspi = spi_master_get_devdata(master); + int ret; + + ret = clk_prepare_enable(tspi->clk); + if (ret < 0) { + dev_err(tspi->dev, "clk_prepare failed: %d\n", ret); + return ret; + } + return 0; +} + +static const struct dev_pm_ops tegra_spi_pm_ops = { + SET_RUNTIME_PM_OPS(tegra_spi_runtime_suspend, + tegra_spi_runtime_resume, NULL) + SET_SYSTEM_SLEEP_PM_OPS(tegra_spi_suspend, tegra_spi_resume) +}; +static struct platform_driver tegra_spi_driver = { + .driver = { + .name = "spi-tegra114", + .pm = &tegra_spi_pm_ops, + .of_match_table = tegra_spi_of_match, + }, + .probe = tegra_spi_probe, + .remove = tegra_spi_remove, +}; +module_platform_driver(tegra_spi_driver); + +MODULE_ALIAS("platform:spi-tegra114"); +MODULE_DESCRIPTION("NVIDIA Tegra114 SPI Controller Driver"); +MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/spi/spi-tegra20-sflash.c b/drivers/spi/spi-tegra20-sflash.c new file mode 100644 index 000000000..b6558bb6f --- /dev/null +++ b/drivers/spi/spi-tegra20-sflash.c @@ -0,0 +1,622 @@ +/* + * SPI driver for Nvidia's Tegra20 Serial Flash Controller. + * + * Copyright (c) 2012, NVIDIA CORPORATION. All rights reserved. + * + * Author: Laxman Dewangan <ldewangan@nvidia.com> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <linux/clk.h> +#include <linux/completion.h> +#include <linux/delay.h> +#include <linux/err.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/kthread.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/reset.h> +#include <linux/spi/spi.h> + +#define SPI_COMMAND 0x000 +#define SPI_GO BIT(30) +#define SPI_M_S BIT(28) +#define SPI_ACTIVE_SCLK_MASK (0x3 << 26) +#define SPI_ACTIVE_SCLK_DRIVE_LOW (0 << 26) +#define SPI_ACTIVE_SCLK_DRIVE_HIGH (1 << 26) +#define SPI_ACTIVE_SCLK_PULL_LOW (2 << 26) +#define SPI_ACTIVE_SCLK_PULL_HIGH (3 << 26) + +#define SPI_CK_SDA_FALLING (1 << 21) +#define SPI_CK_SDA_RISING (0 << 21) +#define SPI_CK_SDA_MASK (1 << 21) +#define SPI_ACTIVE_SDA (0x3 << 18) +#define SPI_ACTIVE_SDA_DRIVE_LOW (0 << 18) +#define SPI_ACTIVE_SDA_DRIVE_HIGH (1 << 18) +#define SPI_ACTIVE_SDA_PULL_LOW (2 << 18) +#define SPI_ACTIVE_SDA_PULL_HIGH (3 << 18) + +#define SPI_CS_POL_INVERT BIT(16) +#define SPI_TX_EN BIT(15) +#define SPI_RX_EN BIT(14) +#define SPI_CS_VAL_HIGH BIT(13) +#define SPI_CS_VAL_LOW 0x0 +#define SPI_CS_SW BIT(12) +#define SPI_CS_HW 0x0 +#define SPI_CS_DELAY_MASK (7 << 9) +#define SPI_CS3_EN BIT(8) +#define SPI_CS2_EN BIT(7) +#define SPI_CS1_EN BIT(6) +#define SPI_CS0_EN BIT(5) + +#define SPI_CS_MASK (SPI_CS3_EN | SPI_CS2_EN | \ + SPI_CS1_EN | SPI_CS0_EN) +#define SPI_BIT_LENGTH(x) (((x) & 0x1f) << 0) + +#define SPI_MODES (SPI_ACTIVE_SCLK_MASK | SPI_CK_SDA_MASK) + +#define SPI_STATUS 0x004 +#define SPI_BSY BIT(31) +#define SPI_RDY BIT(30) +#define SPI_TXF_FLUSH BIT(29) +#define SPI_RXF_FLUSH BIT(28) +#define SPI_RX_UNF BIT(27) +#define SPI_TX_OVF BIT(26) +#define SPI_RXF_EMPTY BIT(25) +#define SPI_RXF_FULL BIT(24) +#define SPI_TXF_EMPTY BIT(23) +#define SPI_TXF_FULL BIT(22) +#define SPI_BLK_CNT(count) (((count) & 0xffff) + 1) + +#define SPI_FIFO_ERROR (SPI_RX_UNF | SPI_TX_OVF) +#define SPI_FIFO_EMPTY (SPI_TX_EMPTY | SPI_RX_EMPTY) + +#define SPI_RX_CMP 0x8 +#define SPI_DMA_CTL 0x0C +#define SPI_DMA_EN BIT(31) +#define SPI_IE_RXC BIT(27) +#define SPI_IE_TXC BIT(26) +#define SPI_PACKED BIT(20) +#define SPI_RX_TRIG_MASK (0x3 << 18) +#define SPI_RX_TRIG_1W (0x0 << 18) +#define SPI_RX_TRIG_4W (0x1 << 18) +#define SPI_TX_TRIG_MASK (0x3 << 16) +#define SPI_TX_TRIG_1W (0x0 << 16) +#define SPI_TX_TRIG_4W (0x1 << 16) +#define SPI_DMA_BLK_COUNT(count) (((count) - 1) & 0xFFFF) + +#define SPI_TX_FIFO 0x10 +#define SPI_RX_FIFO 0x20 + +#define DATA_DIR_TX (1 << 0) +#define DATA_DIR_RX (1 << 1) + +#define MAX_CHIP_SELECT 4 +#define SPI_FIFO_DEPTH 4 +#define SPI_DMA_TIMEOUT (msecs_to_jiffies(1000)) + +struct tegra_sflash_data { + struct device *dev; + struct spi_master *master; + spinlock_t lock; + + struct clk *clk; + struct reset_control *rst; + void __iomem *base; + unsigned irq; + u32 cur_speed; + + struct spi_device *cur_spi; + unsigned cur_pos; + unsigned cur_len; + unsigned bytes_per_word; + unsigned cur_direction; + unsigned curr_xfer_words; + + unsigned cur_rx_pos; + unsigned cur_tx_pos; + + u32 tx_status; + u32 rx_status; + u32 status_reg; + + u32 def_command_reg; + u32 command_reg; + u32 dma_control_reg; + + struct completion xfer_completion; + struct spi_transfer *curr_xfer; +}; + +static int tegra_sflash_runtime_suspend(struct device *dev); +static int tegra_sflash_runtime_resume(struct device *dev); + +static inline u32 tegra_sflash_readl(struct tegra_sflash_data *tsd, + unsigned long reg) +{ + return readl(tsd->base + reg); +} + +static inline void tegra_sflash_writel(struct tegra_sflash_data *tsd, + u32 val, unsigned long reg) +{ + writel(val, tsd->base + reg); +} + +static void tegra_sflash_clear_status(struct tegra_sflash_data *tsd) +{ + /* Write 1 to clear status register */ + tegra_sflash_writel(tsd, SPI_RDY | SPI_FIFO_ERROR, SPI_STATUS); +} + +static unsigned tegra_sflash_calculate_curr_xfer_param( + struct spi_device *spi, struct tegra_sflash_data *tsd, + struct spi_transfer *t) +{ + unsigned remain_len = t->len - tsd->cur_pos; + unsigned max_word; + + tsd->bytes_per_word = DIV_ROUND_UP(t->bits_per_word, 8); + max_word = remain_len / tsd->bytes_per_word; + if (max_word > SPI_FIFO_DEPTH) + max_word = SPI_FIFO_DEPTH; + tsd->curr_xfer_words = max_word; + return max_word; +} + +static unsigned tegra_sflash_fill_tx_fifo_from_client_txbuf( + struct tegra_sflash_data *tsd, struct spi_transfer *t) +{ + unsigned nbytes; + u32 status; + unsigned max_n_32bit = tsd->curr_xfer_words; + u8 *tx_buf = (u8 *)t->tx_buf + tsd->cur_tx_pos; + + if (max_n_32bit > SPI_FIFO_DEPTH) + max_n_32bit = SPI_FIFO_DEPTH; + nbytes = max_n_32bit * tsd->bytes_per_word; + + status = tegra_sflash_readl(tsd, SPI_STATUS); + while (!(status & SPI_TXF_FULL)) { + int i; + u32 x = 0; + + for (i = 0; nbytes && (i < tsd->bytes_per_word); + i++, nbytes--) + x |= (u32)(*tx_buf++) << (i * 8); + tegra_sflash_writel(tsd, x, SPI_TX_FIFO); + if (!nbytes) + break; + + status = tegra_sflash_readl(tsd, SPI_STATUS); + } + tsd->cur_tx_pos += max_n_32bit * tsd->bytes_per_word; + return max_n_32bit; +} + +static int tegra_sflash_read_rx_fifo_to_client_rxbuf( + struct tegra_sflash_data *tsd, struct spi_transfer *t) +{ + u32 status; + unsigned int read_words = 0; + u8 *rx_buf = (u8 *)t->rx_buf + tsd->cur_rx_pos; + + status = tegra_sflash_readl(tsd, SPI_STATUS); + while (!(status & SPI_RXF_EMPTY)) { + int i; + u32 x = tegra_sflash_readl(tsd, SPI_RX_FIFO); + + for (i = 0; (i < tsd->bytes_per_word); i++) + *rx_buf++ = (x >> (i*8)) & 0xFF; + read_words++; + status = tegra_sflash_readl(tsd, SPI_STATUS); + } + tsd->cur_rx_pos += read_words * tsd->bytes_per_word; + return 0; +} + +static int tegra_sflash_start_cpu_based_transfer( + struct tegra_sflash_data *tsd, struct spi_transfer *t) +{ + u32 val = 0; + unsigned cur_words; + + if (tsd->cur_direction & DATA_DIR_TX) + val |= SPI_IE_TXC; + + if (tsd->cur_direction & DATA_DIR_RX) + val |= SPI_IE_RXC; + + tegra_sflash_writel(tsd, val, SPI_DMA_CTL); + tsd->dma_control_reg = val; + + if (tsd->cur_direction & DATA_DIR_TX) + cur_words = tegra_sflash_fill_tx_fifo_from_client_txbuf(tsd, t); + else + cur_words = tsd->curr_xfer_words; + val |= SPI_DMA_BLK_COUNT(cur_words); + tegra_sflash_writel(tsd, val, SPI_DMA_CTL); + tsd->dma_control_reg = val; + val |= SPI_DMA_EN; + tegra_sflash_writel(tsd, val, SPI_DMA_CTL); + return 0; +} + +static int tegra_sflash_start_transfer_one(struct spi_device *spi, + struct spi_transfer *t, bool is_first_of_msg, + bool is_single_xfer) +{ + struct tegra_sflash_data *tsd = spi_master_get_devdata(spi->master); + u32 speed; + u32 command; + + speed = t->speed_hz; + if (speed != tsd->cur_speed) { + clk_set_rate(tsd->clk, speed); + tsd->cur_speed = speed; + } + + tsd->cur_spi = spi; + tsd->cur_pos = 0; + tsd->cur_rx_pos = 0; + tsd->cur_tx_pos = 0; + tsd->curr_xfer = t; + tegra_sflash_calculate_curr_xfer_param(spi, tsd, t); + if (is_first_of_msg) { + command = tsd->def_command_reg; + command |= SPI_BIT_LENGTH(t->bits_per_word - 1); + command |= SPI_CS_VAL_HIGH; + + command &= ~SPI_MODES; + if (spi->mode & SPI_CPHA) + command |= SPI_CK_SDA_FALLING; + + if (spi->mode & SPI_CPOL) + command |= SPI_ACTIVE_SCLK_DRIVE_HIGH; + else + command |= SPI_ACTIVE_SCLK_DRIVE_LOW; + command |= SPI_CS0_EN << spi->chip_select; + } else { + command = tsd->command_reg; + command &= ~SPI_BIT_LENGTH(~0); + command |= SPI_BIT_LENGTH(t->bits_per_word - 1); + command &= ~(SPI_RX_EN | SPI_TX_EN); + } + + tsd->cur_direction = 0; + if (t->rx_buf) { + command |= SPI_RX_EN; + tsd->cur_direction |= DATA_DIR_RX; + } + if (t->tx_buf) { + command |= SPI_TX_EN; + tsd->cur_direction |= DATA_DIR_TX; + } + tegra_sflash_writel(tsd, command, SPI_COMMAND); + tsd->command_reg = command; + + return tegra_sflash_start_cpu_based_transfer(tsd, t); +} + +static int tegra_sflash_transfer_one_message(struct spi_master *master, + struct spi_message *msg) +{ + bool is_first_msg = true; + int single_xfer; + struct tegra_sflash_data *tsd = spi_master_get_devdata(master); + struct spi_transfer *xfer; + struct spi_device *spi = msg->spi; + int ret; + + msg->status = 0; + msg->actual_length = 0; + single_xfer = list_is_singular(&msg->transfers); + list_for_each_entry(xfer, &msg->transfers, transfer_list) { + reinit_completion(&tsd->xfer_completion); + ret = tegra_sflash_start_transfer_one(spi, xfer, + is_first_msg, single_xfer); + if (ret < 0) { + dev_err(tsd->dev, + "spi can not start transfer, err %d\n", ret); + goto exit; + } + is_first_msg = false; + ret = wait_for_completion_timeout(&tsd->xfer_completion, + SPI_DMA_TIMEOUT); + if (WARN_ON(ret == 0)) { + dev_err(tsd->dev, + "spi trasfer timeout, err %d\n", ret); + ret = -EIO; + goto exit; + } + + if (tsd->tx_status || tsd->rx_status) { + dev_err(tsd->dev, "Error in Transfer\n"); + ret = -EIO; + goto exit; + } + msg->actual_length += xfer->len; + if (xfer->cs_change && xfer->delay_usecs) { + tegra_sflash_writel(tsd, tsd->def_command_reg, + SPI_COMMAND); + udelay(xfer->delay_usecs); + } + } + ret = 0; +exit: + tegra_sflash_writel(tsd, tsd->def_command_reg, SPI_COMMAND); + msg->status = ret; + spi_finalize_current_message(master); + return ret; +} + +static irqreturn_t handle_cpu_based_xfer(struct tegra_sflash_data *tsd) +{ + struct spi_transfer *t = tsd->curr_xfer; + unsigned long flags; + + spin_lock_irqsave(&tsd->lock, flags); + if (tsd->tx_status || tsd->rx_status || (tsd->status_reg & SPI_BSY)) { + dev_err(tsd->dev, + "CpuXfer ERROR bit set 0x%x\n", tsd->status_reg); + dev_err(tsd->dev, + "CpuXfer 0x%08x:0x%08x\n", tsd->command_reg, + tsd->dma_control_reg); + reset_control_assert(tsd->rst); + udelay(2); + reset_control_deassert(tsd->rst); + complete(&tsd->xfer_completion); + goto exit; + } + + if (tsd->cur_direction & DATA_DIR_RX) + tegra_sflash_read_rx_fifo_to_client_rxbuf(tsd, t); + + if (tsd->cur_direction & DATA_DIR_TX) + tsd->cur_pos = tsd->cur_tx_pos; + else + tsd->cur_pos = tsd->cur_rx_pos; + + if (tsd->cur_pos == t->len) { + complete(&tsd->xfer_completion); + goto exit; + } + + tegra_sflash_calculate_curr_xfer_param(tsd->cur_spi, tsd, t); + tegra_sflash_start_cpu_based_transfer(tsd, t); +exit: + spin_unlock_irqrestore(&tsd->lock, flags); + return IRQ_HANDLED; +} + +static irqreturn_t tegra_sflash_isr(int irq, void *context_data) +{ + struct tegra_sflash_data *tsd = context_data; + + tsd->status_reg = tegra_sflash_readl(tsd, SPI_STATUS); + if (tsd->cur_direction & DATA_DIR_TX) + tsd->tx_status = tsd->status_reg & SPI_TX_OVF; + + if (tsd->cur_direction & DATA_DIR_RX) + tsd->rx_status = tsd->status_reg & SPI_RX_UNF; + tegra_sflash_clear_status(tsd); + + return handle_cpu_based_xfer(tsd); +} + +static const struct of_device_id tegra_sflash_of_match[] = { + { .compatible = "nvidia,tegra20-sflash", }, + {} +}; +MODULE_DEVICE_TABLE(of, tegra_sflash_of_match); + +static int tegra_sflash_probe(struct platform_device *pdev) +{ + struct spi_master *master; + struct tegra_sflash_data *tsd; + struct resource *r; + int ret; + const struct of_device_id *match; + + match = of_match_device(tegra_sflash_of_match, &pdev->dev); + if (!match) { + dev_err(&pdev->dev, "Error: No device match found\n"); + return -ENODEV; + } + + master = spi_alloc_master(&pdev->dev, sizeof(*tsd)); + if (!master) { + dev_err(&pdev->dev, "master allocation failed\n"); + return -ENOMEM; + } + + /* the spi->mode bits understood by this driver: */ + master->mode_bits = SPI_CPOL | SPI_CPHA; + master->transfer_one_message = tegra_sflash_transfer_one_message; + master->auto_runtime_pm = true; + master->num_chipselect = MAX_CHIP_SELECT; + + platform_set_drvdata(pdev, master); + tsd = spi_master_get_devdata(master); + tsd->master = master; + tsd->dev = &pdev->dev; + spin_lock_init(&tsd->lock); + + if (of_property_read_u32(tsd->dev->of_node, "spi-max-frequency", + &master->max_speed_hz)) + master->max_speed_hz = 25000000; /* 25MHz */ + + r = platform_get_resource(pdev, IORESOURCE_MEM, 0); + tsd->base = devm_ioremap_resource(&pdev->dev, r); + if (IS_ERR(tsd->base)) { + ret = PTR_ERR(tsd->base); + goto exit_free_master; + } + + tsd->irq = platform_get_irq(pdev, 0); + ret = request_irq(tsd->irq, tegra_sflash_isr, 0, + dev_name(&pdev->dev), tsd); + if (ret < 0) { + dev_err(&pdev->dev, "Failed to register ISR for IRQ %d\n", + tsd->irq); + goto exit_free_master; + } + + tsd->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(tsd->clk)) { + dev_err(&pdev->dev, "can not get clock\n"); + ret = PTR_ERR(tsd->clk); + goto exit_free_irq; + } + + tsd->rst = devm_reset_control_get(&pdev->dev, "spi"); + if (IS_ERR(tsd->rst)) { + dev_err(&pdev->dev, "can not get reset\n"); + ret = PTR_ERR(tsd->rst); + goto exit_free_irq; + } + + init_completion(&tsd->xfer_completion); + pm_runtime_enable(&pdev->dev); + if (!pm_runtime_enabled(&pdev->dev)) { + ret = tegra_sflash_runtime_resume(&pdev->dev); + if (ret) + goto exit_pm_disable; + } + + ret = pm_runtime_get_sync(&pdev->dev); + if (ret < 0) { + dev_err(&pdev->dev, "pm runtime get failed, e = %d\n", ret); + goto exit_pm_disable; + } + + /* Reset controller */ + reset_control_assert(tsd->rst); + udelay(2); + reset_control_deassert(tsd->rst); + + tsd->def_command_reg = SPI_M_S | SPI_CS_SW; + tegra_sflash_writel(tsd, tsd->def_command_reg, SPI_COMMAND); + pm_runtime_put(&pdev->dev); + + master->dev.of_node = pdev->dev.of_node; + ret = devm_spi_register_master(&pdev->dev, master); + if (ret < 0) { + dev_err(&pdev->dev, "can not register to master err %d\n", ret); + goto exit_pm_disable; + } + return ret; + +exit_pm_disable: + pm_runtime_disable(&pdev->dev); + if (!pm_runtime_status_suspended(&pdev->dev)) + tegra_sflash_runtime_suspend(&pdev->dev); +exit_free_irq: + free_irq(tsd->irq, tsd); +exit_free_master: + spi_master_put(master); + return ret; +} + +static int tegra_sflash_remove(struct platform_device *pdev) +{ + struct spi_master *master = platform_get_drvdata(pdev); + struct tegra_sflash_data *tsd = spi_master_get_devdata(master); + + free_irq(tsd->irq, tsd); + + pm_runtime_disable(&pdev->dev); + if (!pm_runtime_status_suspended(&pdev->dev)) + tegra_sflash_runtime_suspend(&pdev->dev); + + return 0; +} + +#ifdef CONFIG_PM_SLEEP +static int tegra_sflash_suspend(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + + return spi_master_suspend(master); +} + +static int tegra_sflash_resume(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct tegra_sflash_data *tsd = spi_master_get_devdata(master); + int ret; + + ret = pm_runtime_get_sync(dev); + if (ret < 0) { + dev_err(dev, "pm runtime failed, e = %d\n", ret); + return ret; + } + tegra_sflash_writel(tsd, tsd->command_reg, SPI_COMMAND); + pm_runtime_put(dev); + + return spi_master_resume(master); +} +#endif + +static int tegra_sflash_runtime_suspend(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct tegra_sflash_data *tsd = spi_master_get_devdata(master); + + /* Flush all write which are in PPSB queue by reading back */ + tegra_sflash_readl(tsd, SPI_COMMAND); + + clk_disable_unprepare(tsd->clk); + return 0; +} + +static int tegra_sflash_runtime_resume(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct tegra_sflash_data *tsd = spi_master_get_devdata(master); + int ret; + + ret = clk_prepare_enable(tsd->clk); + if (ret < 0) { + dev_err(tsd->dev, "clk_prepare failed: %d\n", ret); + return ret; + } + return 0; +} + +static const struct dev_pm_ops slink_pm_ops = { + SET_RUNTIME_PM_OPS(tegra_sflash_runtime_suspend, + tegra_sflash_runtime_resume, NULL) + SET_SYSTEM_SLEEP_PM_OPS(tegra_sflash_suspend, tegra_sflash_resume) +}; +static struct platform_driver tegra_sflash_driver = { + .driver = { + .name = "spi-tegra-sflash", + .pm = &slink_pm_ops, + .of_match_table = tegra_sflash_of_match, + }, + .probe = tegra_sflash_probe, + .remove = tegra_sflash_remove, +}; +module_platform_driver(tegra_sflash_driver); + +MODULE_ALIAS("platform:spi-tegra-sflash"); +MODULE_DESCRIPTION("NVIDIA Tegra20 Serial Flash Controller Driver"); +MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/spi/spi-tegra20-slink.c b/drivers/spi/spi-tegra20-slink.c new file mode 100644 index 000000000..85c91f58b --- /dev/null +++ b/drivers/spi/spi-tegra20-slink.c @@ -0,0 +1,1238 @@ +/* + * SPI driver for Nvidia's Tegra20/Tegra30 SLINK Controller. + * + * Copyright (c) 2012, NVIDIA CORPORATION. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <linux/clk.h> +#include <linux/completion.h> +#include <linux/delay.h> +#include <linux/dmaengine.h> +#include <linux/dma-mapping.h> +#include <linux/dmapool.h> +#include <linux/err.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/kthread.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/reset.h> +#include <linux/spi/spi.h> + +#define SLINK_COMMAND 0x000 +#define SLINK_BIT_LENGTH(x) (((x) & 0x1f) << 0) +#define SLINK_WORD_SIZE(x) (((x) & 0x1f) << 5) +#define SLINK_BOTH_EN (1 << 10) +#define SLINK_CS_SW (1 << 11) +#define SLINK_CS_VALUE (1 << 12) +#define SLINK_CS_POLARITY (1 << 13) +#define SLINK_IDLE_SDA_DRIVE_LOW (0 << 16) +#define SLINK_IDLE_SDA_DRIVE_HIGH (1 << 16) +#define SLINK_IDLE_SDA_PULL_LOW (2 << 16) +#define SLINK_IDLE_SDA_PULL_HIGH (3 << 16) +#define SLINK_IDLE_SDA_MASK (3 << 16) +#define SLINK_CS_POLARITY1 (1 << 20) +#define SLINK_CK_SDA (1 << 21) +#define SLINK_CS_POLARITY2 (1 << 22) +#define SLINK_CS_POLARITY3 (1 << 23) +#define SLINK_IDLE_SCLK_DRIVE_LOW (0 << 24) +#define SLINK_IDLE_SCLK_DRIVE_HIGH (1 << 24) +#define SLINK_IDLE_SCLK_PULL_LOW (2 << 24) +#define SLINK_IDLE_SCLK_PULL_HIGH (3 << 24) +#define SLINK_IDLE_SCLK_MASK (3 << 24) +#define SLINK_M_S (1 << 28) +#define SLINK_WAIT (1 << 29) +#define SLINK_GO (1 << 30) +#define SLINK_ENB (1 << 31) + +#define SLINK_MODES (SLINK_IDLE_SCLK_MASK | SLINK_CK_SDA) + +#define SLINK_COMMAND2 0x004 +#define SLINK_LSBFE (1 << 0) +#define SLINK_SSOE (1 << 1) +#define SLINK_SPIE (1 << 4) +#define SLINK_BIDIROE (1 << 6) +#define SLINK_MODFEN (1 << 7) +#define SLINK_INT_SIZE(x) (((x) & 0x1f) << 8) +#define SLINK_CS_ACTIVE_BETWEEN (1 << 17) +#define SLINK_SS_EN_CS(x) (((x) & 0x3) << 18) +#define SLINK_SS_SETUP(x) (((x) & 0x3) << 20) +#define SLINK_FIFO_REFILLS_0 (0 << 22) +#define SLINK_FIFO_REFILLS_1 (1 << 22) +#define SLINK_FIFO_REFILLS_2 (2 << 22) +#define SLINK_FIFO_REFILLS_3 (3 << 22) +#define SLINK_FIFO_REFILLS_MASK (3 << 22) +#define SLINK_WAIT_PACK_INT(x) (((x) & 0x7) << 26) +#define SLINK_SPC0 (1 << 29) +#define SLINK_TXEN (1 << 30) +#define SLINK_RXEN (1 << 31) + +#define SLINK_STATUS 0x008 +#define SLINK_COUNT(val) (((val) >> 0) & 0x1f) +#define SLINK_WORD(val) (((val) >> 5) & 0x1f) +#define SLINK_BLK_CNT(val) (((val) >> 0) & 0xffff) +#define SLINK_MODF (1 << 16) +#define SLINK_RX_UNF (1 << 18) +#define SLINK_TX_OVF (1 << 19) +#define SLINK_TX_FULL (1 << 20) +#define SLINK_TX_EMPTY (1 << 21) +#define SLINK_RX_FULL (1 << 22) +#define SLINK_RX_EMPTY (1 << 23) +#define SLINK_TX_UNF (1 << 24) +#define SLINK_RX_OVF (1 << 25) +#define SLINK_TX_FLUSH (1 << 26) +#define SLINK_RX_FLUSH (1 << 27) +#define SLINK_SCLK (1 << 28) +#define SLINK_ERR (1 << 29) +#define SLINK_RDY (1 << 30) +#define SLINK_BSY (1 << 31) +#define SLINK_FIFO_ERROR (SLINK_TX_OVF | SLINK_RX_UNF | \ + SLINK_TX_UNF | SLINK_RX_OVF) + +#define SLINK_FIFO_EMPTY (SLINK_TX_EMPTY | SLINK_RX_EMPTY) + +#define SLINK_MAS_DATA 0x010 +#define SLINK_SLAVE_DATA 0x014 + +#define SLINK_DMA_CTL 0x018 +#define SLINK_DMA_BLOCK_SIZE(x) (((x) & 0xffff) << 0) +#define SLINK_TX_TRIG_1 (0 << 16) +#define SLINK_TX_TRIG_4 (1 << 16) +#define SLINK_TX_TRIG_8 (2 << 16) +#define SLINK_TX_TRIG_16 (3 << 16) +#define SLINK_TX_TRIG_MASK (3 << 16) +#define SLINK_RX_TRIG_1 (0 << 18) +#define SLINK_RX_TRIG_4 (1 << 18) +#define SLINK_RX_TRIG_8 (2 << 18) +#define SLINK_RX_TRIG_16 (3 << 18) +#define SLINK_RX_TRIG_MASK (3 << 18) +#define SLINK_PACKED (1 << 20) +#define SLINK_PACK_SIZE_4 (0 << 21) +#define SLINK_PACK_SIZE_8 (1 << 21) +#define SLINK_PACK_SIZE_16 (2 << 21) +#define SLINK_PACK_SIZE_32 (3 << 21) +#define SLINK_PACK_SIZE_MASK (3 << 21) +#define SLINK_IE_TXC (1 << 26) +#define SLINK_IE_RXC (1 << 27) +#define SLINK_DMA_EN (1 << 31) + +#define SLINK_STATUS2 0x01c +#define SLINK_TX_FIFO_EMPTY_COUNT(val) (((val) & 0x3f) >> 0) +#define SLINK_RX_FIFO_FULL_COUNT(val) (((val) & 0x3f0000) >> 16) +#define SLINK_SS_HOLD_TIME(val) (((val) & 0xF) << 6) + +#define SLINK_TX_FIFO 0x100 +#define SLINK_RX_FIFO 0x180 + +#define DATA_DIR_TX (1 << 0) +#define DATA_DIR_RX (1 << 1) + +#define SLINK_DMA_TIMEOUT (msecs_to_jiffies(1000)) + +#define DEFAULT_SPI_DMA_BUF_LEN (16*1024) +#define TX_FIFO_EMPTY_COUNT_MAX SLINK_TX_FIFO_EMPTY_COUNT(0x20) +#define RX_FIFO_FULL_COUNT_ZERO SLINK_RX_FIFO_FULL_COUNT(0) + +#define SLINK_STATUS2_RESET \ + (TX_FIFO_EMPTY_COUNT_MAX | RX_FIFO_FULL_COUNT_ZERO << 16) + +#define MAX_CHIP_SELECT 4 +#define SLINK_FIFO_DEPTH 32 + +struct tegra_slink_chip_data { + bool cs_hold_time; +}; + +struct tegra_slink_data { + struct device *dev; + struct spi_master *master; + const struct tegra_slink_chip_data *chip_data; + spinlock_t lock; + + struct clk *clk; + struct reset_control *rst; + void __iomem *base; + phys_addr_t phys; + unsigned irq; + u32 cur_speed; + + struct spi_device *cur_spi; + unsigned cur_pos; + unsigned cur_len; + unsigned words_per_32bit; + unsigned bytes_per_word; + unsigned curr_dma_words; + unsigned cur_direction; + + unsigned cur_rx_pos; + unsigned cur_tx_pos; + + unsigned dma_buf_size; + unsigned max_buf_size; + bool is_curr_dma_xfer; + + struct completion rx_dma_complete; + struct completion tx_dma_complete; + + u32 tx_status; + u32 rx_status; + u32 status_reg; + bool is_packed; + u32 packed_size; + + u32 command_reg; + u32 command2_reg; + u32 dma_control_reg; + u32 def_command_reg; + u32 def_command2_reg; + + struct completion xfer_completion; + struct spi_transfer *curr_xfer; + struct dma_chan *rx_dma_chan; + u32 *rx_dma_buf; + dma_addr_t rx_dma_phys; + struct dma_async_tx_descriptor *rx_dma_desc; + + struct dma_chan *tx_dma_chan; + u32 *tx_dma_buf; + dma_addr_t tx_dma_phys; + struct dma_async_tx_descriptor *tx_dma_desc; +}; + +static int tegra_slink_runtime_suspend(struct device *dev); +static int tegra_slink_runtime_resume(struct device *dev); + +static inline u32 tegra_slink_readl(struct tegra_slink_data *tspi, + unsigned long reg) +{ + return readl(tspi->base + reg); +} + +static inline void tegra_slink_writel(struct tegra_slink_data *tspi, + u32 val, unsigned long reg) +{ + writel(val, tspi->base + reg); + + /* Read back register to make sure that register writes completed */ + if (reg != SLINK_TX_FIFO) + readl(tspi->base + SLINK_MAS_DATA); +} + +static void tegra_slink_clear_status(struct tegra_slink_data *tspi) +{ + u32 val_write; + + tegra_slink_readl(tspi, SLINK_STATUS); + + /* Write 1 to clear status register */ + val_write = SLINK_RDY | SLINK_FIFO_ERROR; + tegra_slink_writel(tspi, val_write, SLINK_STATUS); +} + +static u32 tegra_slink_get_packed_size(struct tegra_slink_data *tspi, + struct spi_transfer *t) +{ + switch (tspi->bytes_per_word) { + case 0: + return SLINK_PACK_SIZE_4; + case 1: + return SLINK_PACK_SIZE_8; + case 2: + return SLINK_PACK_SIZE_16; + case 4: + return SLINK_PACK_SIZE_32; + default: + return 0; + } +} + +static unsigned tegra_slink_calculate_curr_xfer_param( + struct spi_device *spi, struct tegra_slink_data *tspi, + struct spi_transfer *t) +{ + unsigned remain_len = t->len - tspi->cur_pos; + unsigned max_word; + unsigned bits_per_word; + unsigned max_len; + unsigned total_fifo_words; + + bits_per_word = t->bits_per_word; + tspi->bytes_per_word = DIV_ROUND_UP(bits_per_word, 8); + + if (bits_per_word == 8 || bits_per_word == 16) { + tspi->is_packed = 1; + tspi->words_per_32bit = 32/bits_per_word; + } else { + tspi->is_packed = 0; + tspi->words_per_32bit = 1; + } + tspi->packed_size = tegra_slink_get_packed_size(tspi, t); + + if (tspi->is_packed) { + max_len = min(remain_len, tspi->max_buf_size); + tspi->curr_dma_words = max_len/tspi->bytes_per_word; + total_fifo_words = max_len/4; + } else { + max_word = (remain_len - 1) / tspi->bytes_per_word + 1; + max_word = min(max_word, tspi->max_buf_size/4); + tspi->curr_dma_words = max_word; + total_fifo_words = max_word; + } + return total_fifo_words; +} + +static unsigned tegra_slink_fill_tx_fifo_from_client_txbuf( + struct tegra_slink_data *tspi, struct spi_transfer *t) +{ + unsigned nbytes; + unsigned tx_empty_count; + u32 fifo_status; + unsigned max_n_32bit; + unsigned i, count; + unsigned int written_words; + unsigned fifo_words_left; + u8 *tx_buf = (u8 *)t->tx_buf + tspi->cur_tx_pos; + + fifo_status = tegra_slink_readl(tspi, SLINK_STATUS2); + tx_empty_count = SLINK_TX_FIFO_EMPTY_COUNT(fifo_status); + + if (tspi->is_packed) { + fifo_words_left = tx_empty_count * tspi->words_per_32bit; + written_words = min(fifo_words_left, tspi->curr_dma_words); + nbytes = written_words * tspi->bytes_per_word; + max_n_32bit = DIV_ROUND_UP(nbytes, 4); + for (count = 0; count < max_n_32bit; count++) { + u32 x = 0; + for (i = 0; (i < 4) && nbytes; i++, nbytes--) + x |= (u32)(*tx_buf++) << (i * 8); + tegra_slink_writel(tspi, x, SLINK_TX_FIFO); + } + } else { + max_n_32bit = min(tspi->curr_dma_words, tx_empty_count); + written_words = max_n_32bit; + nbytes = written_words * tspi->bytes_per_word; + for (count = 0; count < max_n_32bit; count++) { + u32 x = 0; + for (i = 0; nbytes && (i < tspi->bytes_per_word); + i++, nbytes--) + x |= (u32)(*tx_buf++) << (i * 8); + tegra_slink_writel(tspi, x, SLINK_TX_FIFO); + } + } + tspi->cur_tx_pos += written_words * tspi->bytes_per_word; + return written_words; +} + +static unsigned int tegra_slink_read_rx_fifo_to_client_rxbuf( + struct tegra_slink_data *tspi, struct spi_transfer *t) +{ + unsigned rx_full_count; + u32 fifo_status; + unsigned i, count; + unsigned int read_words = 0; + unsigned len; + u8 *rx_buf = (u8 *)t->rx_buf + tspi->cur_rx_pos; + + fifo_status = tegra_slink_readl(tspi, SLINK_STATUS2); + rx_full_count = SLINK_RX_FIFO_FULL_COUNT(fifo_status); + if (tspi->is_packed) { + len = tspi->curr_dma_words * tspi->bytes_per_word; + for (count = 0; count < rx_full_count; count++) { + u32 x = tegra_slink_readl(tspi, SLINK_RX_FIFO); + for (i = 0; len && (i < 4); i++, len--) + *rx_buf++ = (x >> i*8) & 0xFF; + } + tspi->cur_rx_pos += tspi->curr_dma_words * tspi->bytes_per_word; + read_words += tspi->curr_dma_words; + } else { + for (count = 0; count < rx_full_count; count++) { + u32 x = tegra_slink_readl(tspi, SLINK_RX_FIFO); + for (i = 0; (i < tspi->bytes_per_word); i++) + *rx_buf++ = (x >> (i*8)) & 0xFF; + } + tspi->cur_rx_pos += rx_full_count * tspi->bytes_per_word; + read_words += rx_full_count; + } + return read_words; +} + +static void tegra_slink_copy_client_txbuf_to_spi_txbuf( + struct tegra_slink_data *tspi, struct spi_transfer *t) +{ + /* Make the dma buffer to read by cpu */ + dma_sync_single_for_cpu(tspi->dev, tspi->tx_dma_phys, + tspi->dma_buf_size, DMA_TO_DEVICE); + + if (tspi->is_packed) { + unsigned len = tspi->curr_dma_words * tspi->bytes_per_word; + memcpy(tspi->tx_dma_buf, t->tx_buf + tspi->cur_pos, len); + } else { + unsigned int i; + unsigned int count; + u8 *tx_buf = (u8 *)t->tx_buf + tspi->cur_tx_pos; + unsigned consume = tspi->curr_dma_words * tspi->bytes_per_word; + + for (count = 0; count < tspi->curr_dma_words; count++) { + u32 x = 0; + for (i = 0; consume && (i < tspi->bytes_per_word); + i++, consume--) + x |= (u32)(*tx_buf++) << (i * 8); + tspi->tx_dma_buf[count] = x; + } + } + tspi->cur_tx_pos += tspi->curr_dma_words * tspi->bytes_per_word; + + /* Make the dma buffer to read by dma */ + dma_sync_single_for_device(tspi->dev, tspi->tx_dma_phys, + tspi->dma_buf_size, DMA_TO_DEVICE); +} + +static void tegra_slink_copy_spi_rxbuf_to_client_rxbuf( + struct tegra_slink_data *tspi, struct spi_transfer *t) +{ + unsigned len; + + /* Make the dma buffer to read by cpu */ + dma_sync_single_for_cpu(tspi->dev, tspi->rx_dma_phys, + tspi->dma_buf_size, DMA_FROM_DEVICE); + + if (tspi->is_packed) { + len = tspi->curr_dma_words * tspi->bytes_per_word; + memcpy(t->rx_buf + tspi->cur_rx_pos, tspi->rx_dma_buf, len); + } else { + unsigned int i; + unsigned int count; + unsigned char *rx_buf = t->rx_buf + tspi->cur_rx_pos; + u32 rx_mask = ((u32)1 << t->bits_per_word) - 1; + + for (count = 0; count < tspi->curr_dma_words; count++) { + u32 x = tspi->rx_dma_buf[count] & rx_mask; + for (i = 0; (i < tspi->bytes_per_word); i++) + *rx_buf++ = (x >> (i*8)) & 0xFF; + } + } + tspi->cur_rx_pos += tspi->curr_dma_words * tspi->bytes_per_word; + + /* Make the dma buffer to read by dma */ + dma_sync_single_for_device(tspi->dev, tspi->rx_dma_phys, + tspi->dma_buf_size, DMA_FROM_DEVICE); +} + +static void tegra_slink_dma_complete(void *args) +{ + struct completion *dma_complete = args; + + complete(dma_complete); +} + +static int tegra_slink_start_tx_dma(struct tegra_slink_data *tspi, int len) +{ + reinit_completion(&tspi->tx_dma_complete); + tspi->tx_dma_desc = dmaengine_prep_slave_single(tspi->tx_dma_chan, + tspi->tx_dma_phys, len, DMA_MEM_TO_DEV, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + if (!tspi->tx_dma_desc) { + dev_err(tspi->dev, "Not able to get desc for Tx\n"); + return -EIO; + } + + tspi->tx_dma_desc->callback = tegra_slink_dma_complete; + tspi->tx_dma_desc->callback_param = &tspi->tx_dma_complete; + + dmaengine_submit(tspi->tx_dma_desc); + dma_async_issue_pending(tspi->tx_dma_chan); + return 0; +} + +static int tegra_slink_start_rx_dma(struct tegra_slink_data *tspi, int len) +{ + reinit_completion(&tspi->rx_dma_complete); + tspi->rx_dma_desc = dmaengine_prep_slave_single(tspi->rx_dma_chan, + tspi->rx_dma_phys, len, DMA_DEV_TO_MEM, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + if (!tspi->rx_dma_desc) { + dev_err(tspi->dev, "Not able to get desc for Rx\n"); + return -EIO; + } + + tspi->rx_dma_desc->callback = tegra_slink_dma_complete; + tspi->rx_dma_desc->callback_param = &tspi->rx_dma_complete; + + dmaengine_submit(tspi->rx_dma_desc); + dma_async_issue_pending(tspi->rx_dma_chan); + return 0; +} + +static int tegra_slink_start_dma_based_transfer( + struct tegra_slink_data *tspi, struct spi_transfer *t) +{ + u32 val; + unsigned int len; + int ret = 0; + u32 status; + + /* Make sure that Rx and Tx fifo are empty */ + status = tegra_slink_readl(tspi, SLINK_STATUS); + if ((status & SLINK_FIFO_EMPTY) != SLINK_FIFO_EMPTY) { + dev_err(tspi->dev, "Rx/Tx fifo are not empty status 0x%08x\n", + (unsigned)status); + return -EIO; + } + + val = SLINK_DMA_BLOCK_SIZE(tspi->curr_dma_words - 1); + val |= tspi->packed_size; + if (tspi->is_packed) + len = DIV_ROUND_UP(tspi->curr_dma_words * tspi->bytes_per_word, + 4) * 4; + else + len = tspi->curr_dma_words * 4; + + /* Set attention level based on length of transfer */ + if (len & 0xF) + val |= SLINK_TX_TRIG_1 | SLINK_RX_TRIG_1; + else if (((len) >> 4) & 0x1) + val |= SLINK_TX_TRIG_4 | SLINK_RX_TRIG_4; + else + val |= SLINK_TX_TRIG_8 | SLINK_RX_TRIG_8; + + if (tspi->cur_direction & DATA_DIR_TX) + val |= SLINK_IE_TXC; + + if (tspi->cur_direction & DATA_DIR_RX) + val |= SLINK_IE_RXC; + + tegra_slink_writel(tspi, val, SLINK_DMA_CTL); + tspi->dma_control_reg = val; + + if (tspi->cur_direction & DATA_DIR_TX) { + tegra_slink_copy_client_txbuf_to_spi_txbuf(tspi, t); + wmb(); + ret = tegra_slink_start_tx_dma(tspi, len); + if (ret < 0) { + dev_err(tspi->dev, + "Starting tx dma failed, err %d\n", ret); + return ret; + } + + /* Wait for tx fifo to be fill before starting slink */ + status = tegra_slink_readl(tspi, SLINK_STATUS); + while (!(status & SLINK_TX_FULL)) + status = tegra_slink_readl(tspi, SLINK_STATUS); + } + + if (tspi->cur_direction & DATA_DIR_RX) { + /* Make the dma buffer to read by dma */ + dma_sync_single_for_device(tspi->dev, tspi->rx_dma_phys, + tspi->dma_buf_size, DMA_FROM_DEVICE); + + ret = tegra_slink_start_rx_dma(tspi, len); + if (ret < 0) { + dev_err(tspi->dev, + "Starting rx dma failed, err %d\n", ret); + if (tspi->cur_direction & DATA_DIR_TX) + dmaengine_terminate_all(tspi->tx_dma_chan); + return ret; + } + } + tspi->is_curr_dma_xfer = true; + if (tspi->is_packed) { + val |= SLINK_PACKED; + tegra_slink_writel(tspi, val, SLINK_DMA_CTL); + /* HW need small delay after settign Packed mode */ + udelay(1); + } + tspi->dma_control_reg = val; + + val |= SLINK_DMA_EN; + tegra_slink_writel(tspi, val, SLINK_DMA_CTL); + return ret; +} + +static int tegra_slink_start_cpu_based_transfer( + struct tegra_slink_data *tspi, struct spi_transfer *t) +{ + u32 val; + unsigned cur_words; + + val = tspi->packed_size; + if (tspi->cur_direction & DATA_DIR_TX) + val |= SLINK_IE_TXC; + + if (tspi->cur_direction & DATA_DIR_RX) + val |= SLINK_IE_RXC; + + tegra_slink_writel(tspi, val, SLINK_DMA_CTL); + tspi->dma_control_reg = val; + + if (tspi->cur_direction & DATA_DIR_TX) + cur_words = tegra_slink_fill_tx_fifo_from_client_txbuf(tspi, t); + else + cur_words = tspi->curr_dma_words; + val |= SLINK_DMA_BLOCK_SIZE(cur_words - 1); + tegra_slink_writel(tspi, val, SLINK_DMA_CTL); + tspi->dma_control_reg = val; + + tspi->is_curr_dma_xfer = false; + if (tspi->is_packed) { + val |= SLINK_PACKED; + tegra_slink_writel(tspi, val, SLINK_DMA_CTL); + udelay(1); + wmb(); + } + tspi->dma_control_reg = val; + val |= SLINK_DMA_EN; + tegra_slink_writel(tspi, val, SLINK_DMA_CTL); + return 0; +} + +static int tegra_slink_init_dma_param(struct tegra_slink_data *tspi, + bool dma_to_memory) +{ + struct dma_chan *dma_chan; + u32 *dma_buf; + dma_addr_t dma_phys; + int ret; + struct dma_slave_config dma_sconfig; + + dma_chan = dma_request_slave_channel_reason(tspi->dev, + dma_to_memory ? "rx" : "tx"); + if (IS_ERR(dma_chan)) { + ret = PTR_ERR(dma_chan); + if (ret != -EPROBE_DEFER) + dev_err(tspi->dev, + "Dma channel is not available: %d\n", ret); + return ret; + } + + dma_buf = dma_alloc_coherent(tspi->dev, tspi->dma_buf_size, + &dma_phys, GFP_KERNEL); + if (!dma_buf) { + dev_err(tspi->dev, " Not able to allocate the dma buffer\n"); + dma_release_channel(dma_chan); + return -ENOMEM; + } + + if (dma_to_memory) { + dma_sconfig.src_addr = tspi->phys + SLINK_RX_FIFO; + dma_sconfig.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; + dma_sconfig.src_maxburst = 0; + } else { + dma_sconfig.dst_addr = tspi->phys + SLINK_TX_FIFO; + dma_sconfig.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; + dma_sconfig.dst_maxburst = 0; + } + + ret = dmaengine_slave_config(dma_chan, &dma_sconfig); + if (ret) + goto scrub; + if (dma_to_memory) { + tspi->rx_dma_chan = dma_chan; + tspi->rx_dma_buf = dma_buf; + tspi->rx_dma_phys = dma_phys; + } else { + tspi->tx_dma_chan = dma_chan; + tspi->tx_dma_buf = dma_buf; + tspi->tx_dma_phys = dma_phys; + } + return 0; + +scrub: + dma_free_coherent(tspi->dev, tspi->dma_buf_size, dma_buf, dma_phys); + dma_release_channel(dma_chan); + return ret; +} + +static void tegra_slink_deinit_dma_param(struct tegra_slink_data *tspi, + bool dma_to_memory) +{ + u32 *dma_buf; + dma_addr_t dma_phys; + struct dma_chan *dma_chan; + + if (dma_to_memory) { + dma_buf = tspi->rx_dma_buf; + dma_chan = tspi->rx_dma_chan; + dma_phys = tspi->rx_dma_phys; + tspi->rx_dma_chan = NULL; + tspi->rx_dma_buf = NULL; + } else { + dma_buf = tspi->tx_dma_buf; + dma_chan = tspi->tx_dma_chan; + dma_phys = tspi->tx_dma_phys; + tspi->tx_dma_buf = NULL; + tspi->tx_dma_chan = NULL; + } + if (!dma_chan) + return; + + dma_free_coherent(tspi->dev, tspi->dma_buf_size, dma_buf, dma_phys); + dma_release_channel(dma_chan); +} + +static int tegra_slink_start_transfer_one(struct spi_device *spi, + struct spi_transfer *t) +{ + struct tegra_slink_data *tspi = spi_master_get_devdata(spi->master); + u32 speed; + u8 bits_per_word; + unsigned total_fifo_words; + int ret; + u32 command; + u32 command2; + + bits_per_word = t->bits_per_word; + speed = t->speed_hz; + if (speed != tspi->cur_speed) { + clk_set_rate(tspi->clk, speed * 4); + tspi->cur_speed = speed; + } + + tspi->cur_spi = spi; + tspi->cur_pos = 0; + tspi->cur_rx_pos = 0; + tspi->cur_tx_pos = 0; + tspi->curr_xfer = t; + total_fifo_words = tegra_slink_calculate_curr_xfer_param(spi, tspi, t); + + command = tspi->command_reg; + command &= ~SLINK_BIT_LENGTH(~0); + command |= SLINK_BIT_LENGTH(bits_per_word - 1); + + command2 = tspi->command2_reg; + command2 &= ~(SLINK_RXEN | SLINK_TXEN); + + tegra_slink_writel(tspi, command, SLINK_COMMAND); + tspi->command_reg = command; + + tspi->cur_direction = 0; + if (t->rx_buf) { + command2 |= SLINK_RXEN; + tspi->cur_direction |= DATA_DIR_RX; + } + if (t->tx_buf) { + command2 |= SLINK_TXEN; + tspi->cur_direction |= DATA_DIR_TX; + } + tegra_slink_writel(tspi, command2, SLINK_COMMAND2); + tspi->command2_reg = command2; + + if (total_fifo_words > SLINK_FIFO_DEPTH) + ret = tegra_slink_start_dma_based_transfer(tspi, t); + else + ret = tegra_slink_start_cpu_based_transfer(tspi, t); + return ret; +} + +static int tegra_slink_setup(struct spi_device *spi) +{ + static const u32 cs_pol_bit[MAX_CHIP_SELECT] = { + SLINK_CS_POLARITY, + SLINK_CS_POLARITY1, + SLINK_CS_POLARITY2, + SLINK_CS_POLARITY3, + }; + + struct tegra_slink_data *tspi = spi_master_get_devdata(spi->master); + u32 val; + unsigned long flags; + int ret; + + dev_dbg(&spi->dev, "setup %d bpw, %scpol, %scpha, %dHz\n", + spi->bits_per_word, + spi->mode & SPI_CPOL ? "" : "~", + spi->mode & SPI_CPHA ? "" : "~", + spi->max_speed_hz); + + ret = pm_runtime_get_sync(tspi->dev); + if (ret < 0) { + dev_err(tspi->dev, "pm runtime failed, e = %d\n", ret); + return ret; + } + + spin_lock_irqsave(&tspi->lock, flags); + val = tspi->def_command_reg; + if (spi->mode & SPI_CS_HIGH) + val |= cs_pol_bit[spi->chip_select]; + else + val &= ~cs_pol_bit[spi->chip_select]; + tspi->def_command_reg = val; + tegra_slink_writel(tspi, tspi->def_command_reg, SLINK_COMMAND); + spin_unlock_irqrestore(&tspi->lock, flags); + + pm_runtime_put(tspi->dev); + return 0; +} + +static int tegra_slink_prepare_message(struct spi_master *master, + struct spi_message *msg) +{ + struct tegra_slink_data *tspi = spi_master_get_devdata(master); + struct spi_device *spi = msg->spi; + + tegra_slink_clear_status(tspi); + + tspi->command_reg = tspi->def_command_reg; + tspi->command_reg |= SLINK_CS_SW | SLINK_CS_VALUE; + + tspi->command2_reg = tspi->def_command2_reg; + tspi->command2_reg |= SLINK_SS_EN_CS(spi->chip_select); + + tspi->command_reg &= ~SLINK_MODES; + if (spi->mode & SPI_CPHA) + tspi->command_reg |= SLINK_CK_SDA; + + if (spi->mode & SPI_CPOL) + tspi->command_reg |= SLINK_IDLE_SCLK_DRIVE_HIGH; + else + tspi->command_reg |= SLINK_IDLE_SCLK_DRIVE_LOW; + + return 0; +} + +static int tegra_slink_transfer_one(struct spi_master *master, + struct spi_device *spi, + struct spi_transfer *xfer) +{ + struct tegra_slink_data *tspi = spi_master_get_devdata(master); + int ret; + + reinit_completion(&tspi->xfer_completion); + ret = tegra_slink_start_transfer_one(spi, xfer); + if (ret < 0) { + dev_err(tspi->dev, + "spi can not start transfer, err %d\n", ret); + return ret; + } + + ret = wait_for_completion_timeout(&tspi->xfer_completion, + SLINK_DMA_TIMEOUT); + if (WARN_ON(ret == 0)) { + dev_err(tspi->dev, + "spi trasfer timeout, err %d\n", ret); + return -EIO; + } + + if (tspi->tx_status) + return tspi->tx_status; + if (tspi->rx_status) + return tspi->rx_status; + + return 0; +} + +static int tegra_slink_unprepare_message(struct spi_master *master, + struct spi_message *msg) +{ + struct tegra_slink_data *tspi = spi_master_get_devdata(master); + + tegra_slink_writel(tspi, tspi->def_command_reg, SLINK_COMMAND); + tegra_slink_writel(tspi, tspi->def_command2_reg, SLINK_COMMAND2); + + return 0; +} + +static irqreturn_t handle_cpu_based_xfer(struct tegra_slink_data *tspi) +{ + struct spi_transfer *t = tspi->curr_xfer; + unsigned long flags; + + spin_lock_irqsave(&tspi->lock, flags); + if (tspi->tx_status || tspi->rx_status || + (tspi->status_reg & SLINK_BSY)) { + dev_err(tspi->dev, + "CpuXfer ERROR bit set 0x%x\n", tspi->status_reg); + dev_err(tspi->dev, + "CpuXfer 0x%08x:0x%08x:0x%08x\n", tspi->command_reg, + tspi->command2_reg, tspi->dma_control_reg); + reset_control_assert(tspi->rst); + udelay(2); + reset_control_deassert(tspi->rst); + complete(&tspi->xfer_completion); + goto exit; + } + + if (tspi->cur_direction & DATA_DIR_RX) + tegra_slink_read_rx_fifo_to_client_rxbuf(tspi, t); + + if (tspi->cur_direction & DATA_DIR_TX) + tspi->cur_pos = tspi->cur_tx_pos; + else + tspi->cur_pos = tspi->cur_rx_pos; + + if (tspi->cur_pos == t->len) { + complete(&tspi->xfer_completion); + goto exit; + } + + tegra_slink_calculate_curr_xfer_param(tspi->cur_spi, tspi, t); + tegra_slink_start_cpu_based_transfer(tspi, t); +exit: + spin_unlock_irqrestore(&tspi->lock, flags); + return IRQ_HANDLED; +} + +static irqreturn_t handle_dma_based_xfer(struct tegra_slink_data *tspi) +{ + struct spi_transfer *t = tspi->curr_xfer; + long wait_status; + int err = 0; + unsigned total_fifo_words; + unsigned long flags; + + /* Abort dmas if any error */ + if (tspi->cur_direction & DATA_DIR_TX) { + if (tspi->tx_status) { + dmaengine_terminate_all(tspi->tx_dma_chan); + err += 1; + } else { + wait_status = wait_for_completion_interruptible_timeout( + &tspi->tx_dma_complete, SLINK_DMA_TIMEOUT); + if (wait_status <= 0) { + dmaengine_terminate_all(tspi->tx_dma_chan); + dev_err(tspi->dev, "TxDma Xfer failed\n"); + err += 1; + } + } + } + + if (tspi->cur_direction & DATA_DIR_RX) { + if (tspi->rx_status) { + dmaengine_terminate_all(tspi->rx_dma_chan); + err += 2; + } else { + wait_status = wait_for_completion_interruptible_timeout( + &tspi->rx_dma_complete, SLINK_DMA_TIMEOUT); + if (wait_status <= 0) { + dmaengine_terminate_all(tspi->rx_dma_chan); + dev_err(tspi->dev, "RxDma Xfer failed\n"); + err += 2; + } + } + } + + spin_lock_irqsave(&tspi->lock, flags); + if (err) { + dev_err(tspi->dev, + "DmaXfer: ERROR bit set 0x%x\n", tspi->status_reg); + dev_err(tspi->dev, + "DmaXfer 0x%08x:0x%08x:0x%08x\n", tspi->command_reg, + tspi->command2_reg, tspi->dma_control_reg); + reset_control_assert(tspi->rst); + udelay(2); + reset_control_assert(tspi->rst); + complete(&tspi->xfer_completion); + spin_unlock_irqrestore(&tspi->lock, flags); + return IRQ_HANDLED; + } + + if (tspi->cur_direction & DATA_DIR_RX) + tegra_slink_copy_spi_rxbuf_to_client_rxbuf(tspi, t); + + if (tspi->cur_direction & DATA_DIR_TX) + tspi->cur_pos = tspi->cur_tx_pos; + else + tspi->cur_pos = tspi->cur_rx_pos; + + if (tspi->cur_pos == t->len) { + complete(&tspi->xfer_completion); + goto exit; + } + + /* Continue transfer in current message */ + total_fifo_words = tegra_slink_calculate_curr_xfer_param(tspi->cur_spi, + tspi, t); + if (total_fifo_words > SLINK_FIFO_DEPTH) + err = tegra_slink_start_dma_based_transfer(tspi, t); + else + err = tegra_slink_start_cpu_based_transfer(tspi, t); + +exit: + spin_unlock_irqrestore(&tspi->lock, flags); + return IRQ_HANDLED; +} + +static irqreturn_t tegra_slink_isr_thread(int irq, void *context_data) +{ + struct tegra_slink_data *tspi = context_data; + + if (!tspi->is_curr_dma_xfer) + return handle_cpu_based_xfer(tspi); + return handle_dma_based_xfer(tspi); +} + +static irqreturn_t tegra_slink_isr(int irq, void *context_data) +{ + struct tegra_slink_data *tspi = context_data; + + tspi->status_reg = tegra_slink_readl(tspi, SLINK_STATUS); + if (tspi->cur_direction & DATA_DIR_TX) + tspi->tx_status = tspi->status_reg & + (SLINK_TX_OVF | SLINK_TX_UNF); + + if (tspi->cur_direction & DATA_DIR_RX) + tspi->rx_status = tspi->status_reg & + (SLINK_RX_OVF | SLINK_RX_UNF); + tegra_slink_clear_status(tspi); + + return IRQ_WAKE_THREAD; +} + +static const struct tegra_slink_chip_data tegra30_spi_cdata = { + .cs_hold_time = true, +}; + +static const struct tegra_slink_chip_data tegra20_spi_cdata = { + .cs_hold_time = false, +}; + +static const struct of_device_id tegra_slink_of_match[] = { + { .compatible = "nvidia,tegra30-slink", .data = &tegra30_spi_cdata, }, + { .compatible = "nvidia,tegra20-slink", .data = &tegra20_spi_cdata, }, + {} +}; +MODULE_DEVICE_TABLE(of, tegra_slink_of_match); + +static int tegra_slink_probe(struct platform_device *pdev) +{ + struct spi_master *master; + struct tegra_slink_data *tspi; + struct resource *r; + int ret, spi_irq; + const struct tegra_slink_chip_data *cdata = NULL; + const struct of_device_id *match; + + match = of_match_device(tegra_slink_of_match, &pdev->dev); + if (!match) { + dev_err(&pdev->dev, "Error: No device match found\n"); + return -ENODEV; + } + cdata = match->data; + + master = spi_alloc_master(&pdev->dev, sizeof(*tspi)); + if (!master) { + dev_err(&pdev->dev, "master allocation failed\n"); + return -ENOMEM; + } + + /* the spi->mode bits understood by this driver: */ + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH; + master->setup = tegra_slink_setup; + master->prepare_message = tegra_slink_prepare_message; + master->transfer_one = tegra_slink_transfer_one; + master->unprepare_message = tegra_slink_unprepare_message; + master->auto_runtime_pm = true; + master->num_chipselect = MAX_CHIP_SELECT; + + platform_set_drvdata(pdev, master); + tspi = spi_master_get_devdata(master); + tspi->master = master; + tspi->dev = &pdev->dev; + tspi->chip_data = cdata; + spin_lock_init(&tspi->lock); + + if (of_property_read_u32(tspi->dev->of_node, "spi-max-frequency", + &master->max_speed_hz)) + master->max_speed_hz = 25000000; /* 25MHz */ + + r = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!r) { + dev_err(&pdev->dev, "No IO memory resource\n"); + ret = -ENODEV; + goto exit_free_master; + } + tspi->phys = r->start; + tspi->base = devm_ioremap_resource(&pdev->dev, r); + if (IS_ERR(tspi->base)) { + ret = PTR_ERR(tspi->base); + goto exit_free_master; + } + + spi_irq = platform_get_irq(pdev, 0); + tspi->irq = spi_irq; + ret = request_threaded_irq(tspi->irq, tegra_slink_isr, + tegra_slink_isr_thread, IRQF_ONESHOT, + dev_name(&pdev->dev), tspi); + if (ret < 0) { + dev_err(&pdev->dev, "Failed to register ISR for IRQ %d\n", + tspi->irq); + goto exit_free_master; + } + + tspi->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(tspi->clk)) { + dev_err(&pdev->dev, "can not get clock\n"); + ret = PTR_ERR(tspi->clk); + goto exit_free_irq; + } + + tspi->rst = devm_reset_control_get(&pdev->dev, "spi"); + if (IS_ERR(tspi->rst)) { + dev_err(&pdev->dev, "can not get reset\n"); + ret = PTR_ERR(tspi->rst); + goto exit_free_irq; + } + + tspi->max_buf_size = SLINK_FIFO_DEPTH << 2; + tspi->dma_buf_size = DEFAULT_SPI_DMA_BUF_LEN; + + ret = tegra_slink_init_dma_param(tspi, true); + if (ret < 0) + goto exit_free_irq; + ret = tegra_slink_init_dma_param(tspi, false); + if (ret < 0) + goto exit_rx_dma_free; + tspi->max_buf_size = tspi->dma_buf_size; + init_completion(&tspi->tx_dma_complete); + init_completion(&tspi->rx_dma_complete); + + init_completion(&tspi->xfer_completion); + + pm_runtime_enable(&pdev->dev); + if (!pm_runtime_enabled(&pdev->dev)) { + ret = tegra_slink_runtime_resume(&pdev->dev); + if (ret) + goto exit_pm_disable; + } + + ret = pm_runtime_get_sync(&pdev->dev); + if (ret < 0) { + dev_err(&pdev->dev, "pm runtime get failed, e = %d\n", ret); + goto exit_pm_disable; + } + tspi->def_command_reg = SLINK_M_S; + tspi->def_command2_reg = SLINK_CS_ACTIVE_BETWEEN; + tegra_slink_writel(tspi, tspi->def_command_reg, SLINK_COMMAND); + tegra_slink_writel(tspi, tspi->def_command2_reg, SLINK_COMMAND2); + pm_runtime_put(&pdev->dev); + + master->dev.of_node = pdev->dev.of_node; + ret = devm_spi_register_master(&pdev->dev, master); + if (ret < 0) { + dev_err(&pdev->dev, "can not register to master err %d\n", ret); + goto exit_pm_disable; + } + return ret; + +exit_pm_disable: + pm_runtime_disable(&pdev->dev); + if (!pm_runtime_status_suspended(&pdev->dev)) + tegra_slink_runtime_suspend(&pdev->dev); + tegra_slink_deinit_dma_param(tspi, false); +exit_rx_dma_free: + tegra_slink_deinit_dma_param(tspi, true); +exit_free_irq: + free_irq(spi_irq, tspi); +exit_free_master: + spi_master_put(master); + return ret; +} + +static int tegra_slink_remove(struct platform_device *pdev) +{ + struct spi_master *master = platform_get_drvdata(pdev); + struct tegra_slink_data *tspi = spi_master_get_devdata(master); + + free_irq(tspi->irq, tspi); + + if (tspi->tx_dma_chan) + tegra_slink_deinit_dma_param(tspi, false); + + if (tspi->rx_dma_chan) + tegra_slink_deinit_dma_param(tspi, true); + + pm_runtime_disable(&pdev->dev); + if (!pm_runtime_status_suspended(&pdev->dev)) + tegra_slink_runtime_suspend(&pdev->dev); + + return 0; +} + +#ifdef CONFIG_PM_SLEEP +static int tegra_slink_suspend(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + + return spi_master_suspend(master); +} + +static int tegra_slink_resume(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct tegra_slink_data *tspi = spi_master_get_devdata(master); + int ret; + + ret = pm_runtime_get_sync(dev); + if (ret < 0) { + dev_err(dev, "pm runtime failed, e = %d\n", ret); + return ret; + } + tegra_slink_writel(tspi, tspi->command_reg, SLINK_COMMAND); + tegra_slink_writel(tspi, tspi->command2_reg, SLINK_COMMAND2); + pm_runtime_put(dev); + + return spi_master_resume(master); +} +#endif + +static int tegra_slink_runtime_suspend(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct tegra_slink_data *tspi = spi_master_get_devdata(master); + + /* Flush all write which are in PPSB queue by reading back */ + tegra_slink_readl(tspi, SLINK_MAS_DATA); + + clk_disable_unprepare(tspi->clk); + return 0; +} + +static int tegra_slink_runtime_resume(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct tegra_slink_data *tspi = spi_master_get_devdata(master); + int ret; + + ret = clk_prepare_enable(tspi->clk); + if (ret < 0) { + dev_err(tspi->dev, "clk_prepare failed: %d\n", ret); + return ret; + } + return 0; +} + +static const struct dev_pm_ops slink_pm_ops = { + SET_RUNTIME_PM_OPS(tegra_slink_runtime_suspend, + tegra_slink_runtime_resume, NULL) + SET_SYSTEM_SLEEP_PM_OPS(tegra_slink_suspend, tegra_slink_resume) +}; +static struct platform_driver tegra_slink_driver = { + .driver = { + .name = "spi-tegra-slink", + .pm = &slink_pm_ops, + .of_match_table = tegra_slink_of_match, + }, + .probe = tegra_slink_probe, + .remove = tegra_slink_remove, +}; +module_platform_driver(tegra_slink_driver); + +MODULE_ALIAS("platform:spi-tegra-slink"); +MODULE_DESCRIPTION("NVIDIA Tegra20/Tegra30 SLINK Controller Driver"); +MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/spi/spi-ti-qspi.c b/drivers/spi/spi-ti-qspi.c new file mode 100644 index 000000000..5c0616870 --- /dev/null +++ b/drivers/spi/spi-ti-qspi.c @@ -0,0 +1,600 @@ +/* + * TI QSPI driver + * + * Copyright (C) 2013 Texas Instruments Incorporated - http://www.ti.com + * Author: Sourav Poddar <sourav.poddar@ti.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GPLv2. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR /PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/module.h> +#include <linux/device.h> +#include <linux/delay.h> +#include <linux/dma-mapping.h> +#include <linux/dmaengine.h> +#include <linux/omap-dma.h> +#include <linux/platform_device.h> +#include <linux/err.h> +#include <linux/clk.h> +#include <linux/io.h> +#include <linux/slab.h> +#include <linux/pm_runtime.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/pinctrl/consumer.h> + +#include <linux/spi/spi.h> + +struct ti_qspi_regs { + u32 clkctrl; +}; + +struct ti_qspi { + struct completion transfer_complete; + + /* list synchronization */ + struct mutex list_lock; + + struct spi_master *master; + void __iomem *base; + void __iomem *ctrl_base; + void __iomem *mmap_base; + struct clk *fclk; + struct device *dev; + + struct ti_qspi_regs ctx_reg; + + u32 spi_max_frequency; + u32 cmd; + u32 dc; + + bool ctrl_mod; +}; + +#define QSPI_PID (0x0) +#define QSPI_SYSCONFIG (0x10) +#define QSPI_INTR_STATUS_RAW_SET (0x20) +#define QSPI_INTR_STATUS_ENABLED_CLEAR (0x24) +#define QSPI_INTR_ENABLE_SET_REG (0x28) +#define QSPI_INTR_ENABLE_CLEAR_REG (0x2c) +#define QSPI_SPI_CLOCK_CNTRL_REG (0x40) +#define QSPI_SPI_DC_REG (0x44) +#define QSPI_SPI_CMD_REG (0x48) +#define QSPI_SPI_STATUS_REG (0x4c) +#define QSPI_SPI_DATA_REG (0x50) +#define QSPI_SPI_SETUP0_REG (0x54) +#define QSPI_SPI_SWITCH_REG (0x64) +#define QSPI_SPI_SETUP1_REG (0x58) +#define QSPI_SPI_SETUP2_REG (0x5c) +#define QSPI_SPI_SETUP3_REG (0x60) +#define QSPI_SPI_DATA_REG_1 (0x68) +#define QSPI_SPI_DATA_REG_2 (0x6c) +#define QSPI_SPI_DATA_REG_3 (0x70) + +#define QSPI_COMPLETION_TIMEOUT msecs_to_jiffies(2000) + +#define QSPI_FCLK 192000000 + +/* Clock Control */ +#define QSPI_CLK_EN (1 << 31) +#define QSPI_CLK_DIV_MAX 0xffff + +/* Command */ +#define QSPI_EN_CS(n) (n << 28) +#define QSPI_WLEN(n) ((n - 1) << 19) +#define QSPI_3_PIN (1 << 18) +#define QSPI_RD_SNGL (1 << 16) +#define QSPI_WR_SNGL (2 << 16) +#define QSPI_RD_DUAL (3 << 16) +#define QSPI_RD_QUAD (7 << 16) +#define QSPI_INVAL (4 << 16) +#define QSPI_WC_CMD_INT_EN (1 << 14) +#define QSPI_FLEN(n) ((n - 1) << 0) + +/* STATUS REGISTER */ +#define BUSY 0x01 +#define WC 0x02 + +/* INTERRUPT REGISTER */ +#define QSPI_WC_INT_EN (1 << 1) +#define QSPI_WC_INT_DISABLE (1 << 1) + +/* Device Control */ +#define QSPI_DD(m, n) (m << (3 + n * 8)) +#define QSPI_CKPHA(n) (1 << (2 + n * 8)) +#define QSPI_CSPOL(n) (1 << (1 + n * 8)) +#define QSPI_CKPOL(n) (1 << (n * 8)) + +#define QSPI_FRAME 4096 + +#define QSPI_AUTOSUSPEND_TIMEOUT 2000 + +static inline unsigned long ti_qspi_read(struct ti_qspi *qspi, + unsigned long reg) +{ + return readl(qspi->base + reg); +} + +static inline void ti_qspi_write(struct ti_qspi *qspi, + unsigned long val, unsigned long reg) +{ + writel(val, qspi->base + reg); +} + +static int ti_qspi_setup(struct spi_device *spi) +{ + struct ti_qspi *qspi = spi_master_get_devdata(spi->master); + struct ti_qspi_regs *ctx_reg = &qspi->ctx_reg; + int clk_div = 0, ret; + u32 clk_ctrl_reg, clk_rate, clk_mask; + + if (spi->master->busy) { + dev_dbg(qspi->dev, "master busy doing other trasnfers\n"); + return -EBUSY; + } + + if (!qspi->spi_max_frequency) { + dev_err(qspi->dev, "spi max frequency not defined\n"); + return -EINVAL; + } + + clk_rate = clk_get_rate(qspi->fclk); + + clk_div = DIV_ROUND_UP(clk_rate, qspi->spi_max_frequency) - 1; + + if (clk_div < 0) { + dev_dbg(qspi->dev, "clock divider < 0, using /1 divider\n"); + return -EINVAL; + } + + if (clk_div > QSPI_CLK_DIV_MAX) { + dev_dbg(qspi->dev, "clock divider >%d , using /%d divider\n", + QSPI_CLK_DIV_MAX, QSPI_CLK_DIV_MAX + 1); + return -EINVAL; + } + + dev_dbg(qspi->dev, "hz: %d, clock divider %d\n", + qspi->spi_max_frequency, clk_div); + + ret = pm_runtime_get_sync(qspi->dev); + if (ret < 0) { + dev_err(qspi->dev, "pm_runtime_get_sync() failed\n"); + return ret; + } + + clk_ctrl_reg = ti_qspi_read(qspi, QSPI_SPI_CLOCK_CNTRL_REG); + + clk_ctrl_reg &= ~QSPI_CLK_EN; + + /* disable SCLK */ + ti_qspi_write(qspi, clk_ctrl_reg, QSPI_SPI_CLOCK_CNTRL_REG); + + /* enable SCLK */ + clk_mask = QSPI_CLK_EN | clk_div; + ti_qspi_write(qspi, clk_mask, QSPI_SPI_CLOCK_CNTRL_REG); + ctx_reg->clkctrl = clk_mask; + + pm_runtime_mark_last_busy(qspi->dev); + ret = pm_runtime_put_autosuspend(qspi->dev); + if (ret < 0) { + dev_err(qspi->dev, "pm_runtime_put_autosuspend() failed\n"); + return ret; + } + + return 0; +} + +static void ti_qspi_restore_ctx(struct ti_qspi *qspi) +{ + struct ti_qspi_regs *ctx_reg = &qspi->ctx_reg; + + ti_qspi_write(qspi, ctx_reg->clkctrl, QSPI_SPI_CLOCK_CNTRL_REG); +} + +static inline u32 qspi_is_busy(struct ti_qspi *qspi) +{ + u32 stat; + unsigned long timeout = jiffies + QSPI_COMPLETION_TIMEOUT; + + stat = ti_qspi_read(qspi, QSPI_SPI_STATUS_REG); + while ((stat & BUSY) && time_after(timeout, jiffies)) { + cpu_relax(); + stat = ti_qspi_read(qspi, QSPI_SPI_STATUS_REG); + } + + WARN(stat & BUSY, "qspi busy\n"); + return stat & BUSY; +} + +static int qspi_write_msg(struct ti_qspi *qspi, struct spi_transfer *t) +{ + int wlen, count; + unsigned int cmd; + const u8 *txbuf; + + txbuf = t->tx_buf; + cmd = qspi->cmd | QSPI_WR_SNGL; + count = t->len; + wlen = t->bits_per_word >> 3; /* in bytes */ + + while (count) { + if (qspi_is_busy(qspi)) + return -EBUSY; + + switch (wlen) { + case 1: + dev_dbg(qspi->dev, "tx cmd %08x dc %08x data %02x\n", + cmd, qspi->dc, *txbuf); + writeb(*txbuf, qspi->base + QSPI_SPI_DATA_REG); + break; + case 2: + dev_dbg(qspi->dev, "tx cmd %08x dc %08x data %04x\n", + cmd, qspi->dc, *txbuf); + writew(*((u16 *)txbuf), qspi->base + QSPI_SPI_DATA_REG); + break; + case 4: + dev_dbg(qspi->dev, "tx cmd %08x dc %08x data %08x\n", + cmd, qspi->dc, *txbuf); + writel(*((u32 *)txbuf), qspi->base + QSPI_SPI_DATA_REG); + break; + } + + ti_qspi_write(qspi, cmd, QSPI_SPI_CMD_REG); + if (!wait_for_completion_timeout(&qspi->transfer_complete, + QSPI_COMPLETION_TIMEOUT)) { + dev_err(qspi->dev, "write timed out\n"); + return -ETIMEDOUT; + } + txbuf += wlen; + count -= wlen; + } + + return 0; +} + +static int qspi_read_msg(struct ti_qspi *qspi, struct spi_transfer *t) +{ + int wlen, count; + unsigned int cmd; + u8 *rxbuf; + + rxbuf = t->rx_buf; + cmd = qspi->cmd; + switch (t->rx_nbits) { + case SPI_NBITS_DUAL: + cmd |= QSPI_RD_DUAL; + break; + case SPI_NBITS_QUAD: + cmd |= QSPI_RD_QUAD; + break; + default: + cmd |= QSPI_RD_SNGL; + break; + } + count = t->len; + wlen = t->bits_per_word >> 3; /* in bytes */ + + while (count) { + dev_dbg(qspi->dev, "rx cmd %08x dc %08x\n", cmd, qspi->dc); + if (qspi_is_busy(qspi)) + return -EBUSY; + + ti_qspi_write(qspi, cmd, QSPI_SPI_CMD_REG); + if (!wait_for_completion_timeout(&qspi->transfer_complete, + QSPI_COMPLETION_TIMEOUT)) { + dev_err(qspi->dev, "read timed out\n"); + return -ETIMEDOUT; + } + switch (wlen) { + case 1: + *rxbuf = readb(qspi->base + QSPI_SPI_DATA_REG); + break; + case 2: + *((u16 *)rxbuf) = readw(qspi->base + QSPI_SPI_DATA_REG); + break; + case 4: + *((u32 *)rxbuf) = readl(qspi->base + QSPI_SPI_DATA_REG); + break; + } + rxbuf += wlen; + count -= wlen; + } + + return 0; +} + +static int qspi_transfer_msg(struct ti_qspi *qspi, struct spi_transfer *t) +{ + int ret; + + if (t->tx_buf) { + ret = qspi_write_msg(qspi, t); + if (ret) { + dev_dbg(qspi->dev, "Error while writing\n"); + return ret; + } + } + + if (t->rx_buf) { + ret = qspi_read_msg(qspi, t); + if (ret) { + dev_dbg(qspi->dev, "Error while reading\n"); + return ret; + } + } + + return 0; +} + +static int ti_qspi_start_transfer_one(struct spi_master *master, + struct spi_message *m) +{ + struct ti_qspi *qspi = spi_master_get_devdata(master); + struct spi_device *spi = m->spi; + struct spi_transfer *t; + int status = 0, ret; + int frame_length; + + /* setup device control reg */ + qspi->dc = 0; + + if (spi->mode & SPI_CPHA) + qspi->dc |= QSPI_CKPHA(spi->chip_select); + if (spi->mode & SPI_CPOL) + qspi->dc |= QSPI_CKPOL(spi->chip_select); + if (spi->mode & SPI_CS_HIGH) + qspi->dc |= QSPI_CSPOL(spi->chip_select); + + frame_length = (m->frame_length << 3) / spi->bits_per_word; + + frame_length = clamp(frame_length, 0, QSPI_FRAME); + + /* setup command reg */ + qspi->cmd = 0; + qspi->cmd |= QSPI_EN_CS(spi->chip_select); + qspi->cmd |= QSPI_FLEN(frame_length); + qspi->cmd |= QSPI_WC_CMD_INT_EN; + + ti_qspi_write(qspi, QSPI_WC_INT_EN, QSPI_INTR_ENABLE_SET_REG); + ti_qspi_write(qspi, qspi->dc, QSPI_SPI_DC_REG); + + mutex_lock(&qspi->list_lock); + + list_for_each_entry(t, &m->transfers, transfer_list) { + qspi->cmd |= QSPI_WLEN(t->bits_per_word); + + ret = qspi_transfer_msg(qspi, t); + if (ret) { + dev_dbg(qspi->dev, "transfer message failed\n"); + mutex_unlock(&qspi->list_lock); + return -EINVAL; + } + + m->actual_length += t->len; + } + + mutex_unlock(&qspi->list_lock); + + m->status = status; + spi_finalize_current_message(master); + + ti_qspi_write(qspi, qspi->cmd | QSPI_INVAL, QSPI_SPI_CMD_REG); + + return status; +} + +static irqreturn_t ti_qspi_isr(int irq, void *dev_id) +{ + struct ti_qspi *qspi = dev_id; + u16 int_stat; + u32 stat; + + irqreturn_t ret = IRQ_HANDLED; + + int_stat = ti_qspi_read(qspi, QSPI_INTR_STATUS_ENABLED_CLEAR); + stat = ti_qspi_read(qspi, QSPI_SPI_STATUS_REG); + + if (!int_stat) { + dev_dbg(qspi->dev, "No IRQ triggered\n"); + ret = IRQ_NONE; + goto out; + } + + ti_qspi_write(qspi, QSPI_WC_INT_DISABLE, + QSPI_INTR_STATUS_ENABLED_CLEAR); + if (stat & WC) + complete(&qspi->transfer_complete); +out: + return ret; +} + +static int ti_qspi_runtime_resume(struct device *dev) +{ + struct ti_qspi *qspi; + + qspi = dev_get_drvdata(dev); + ti_qspi_restore_ctx(qspi); + + return 0; +} + +static const struct of_device_id ti_qspi_match[] = { + {.compatible = "ti,dra7xxx-qspi" }, + {.compatible = "ti,am4372-qspi" }, + {}, +}; +MODULE_DEVICE_TABLE(of, ti_qspi_match); + +static int ti_qspi_probe(struct platform_device *pdev) +{ + struct ti_qspi *qspi; + struct spi_master *master; + struct resource *r, *res_ctrl, *res_mmap; + struct device_node *np = pdev->dev.of_node; + u32 max_freq; + int ret = 0, num_cs, irq; + + master = spi_alloc_master(&pdev->dev, sizeof(*qspi)); + if (!master) + return -ENOMEM; + + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_RX_DUAL | SPI_RX_QUAD; + + master->flags = SPI_MASTER_HALF_DUPLEX; + master->setup = ti_qspi_setup; + master->auto_runtime_pm = true; + master->transfer_one_message = ti_qspi_start_transfer_one; + master->dev.of_node = pdev->dev.of_node; + master->bits_per_word_mask = SPI_BPW_MASK(32) | SPI_BPW_MASK(16) | + SPI_BPW_MASK(8); + + if (!of_property_read_u32(np, "num-cs", &num_cs)) + master->num_chipselect = num_cs; + + qspi = spi_master_get_devdata(master); + qspi->master = master; + qspi->dev = &pdev->dev; + platform_set_drvdata(pdev, qspi); + + r = platform_get_resource_byname(pdev, IORESOURCE_MEM, "qspi_base"); + if (r == NULL) { + r = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (r == NULL) { + dev_err(&pdev->dev, "missing platform data\n"); + return -ENODEV; + } + } + + res_mmap = platform_get_resource_byname(pdev, + IORESOURCE_MEM, "qspi_mmap"); + if (res_mmap == NULL) { + res_mmap = platform_get_resource(pdev, IORESOURCE_MEM, 1); + if (res_mmap == NULL) { + dev_err(&pdev->dev, + "memory mapped resource not required\n"); + } + } + + res_ctrl = platform_get_resource_byname(pdev, + IORESOURCE_MEM, "qspi_ctrlmod"); + if (res_ctrl == NULL) { + res_ctrl = platform_get_resource(pdev, IORESOURCE_MEM, 2); + if (res_ctrl == NULL) { + dev_dbg(&pdev->dev, + "control module resources not required\n"); + } + } + + irq = platform_get_irq(pdev, 0); + if (irq < 0) { + dev_err(&pdev->dev, "no irq resource?\n"); + return irq; + } + + mutex_init(&qspi->list_lock); + + qspi->base = devm_ioremap_resource(&pdev->dev, r); + if (IS_ERR(qspi->base)) { + ret = PTR_ERR(qspi->base); + goto free_master; + } + + if (res_ctrl) { + qspi->ctrl_mod = true; + qspi->ctrl_base = devm_ioremap_resource(&pdev->dev, res_ctrl); + if (IS_ERR(qspi->ctrl_base)) { + ret = PTR_ERR(qspi->ctrl_base); + goto free_master; + } + } + + if (res_mmap) { + qspi->mmap_base = devm_ioremap_resource(&pdev->dev, res_mmap); + if (IS_ERR(qspi->mmap_base)) { + ret = PTR_ERR(qspi->mmap_base); + goto free_master; + } + } + + ret = devm_request_irq(&pdev->dev, irq, ti_qspi_isr, 0, + dev_name(&pdev->dev), qspi); + if (ret < 0) { + dev_err(&pdev->dev, "Failed to register ISR for IRQ %d\n", + irq); + goto free_master; + } + + qspi->fclk = devm_clk_get(&pdev->dev, "fck"); + if (IS_ERR(qspi->fclk)) { + ret = PTR_ERR(qspi->fclk); + dev_err(&pdev->dev, "could not get clk: %d\n", ret); + } + + init_completion(&qspi->transfer_complete); + + pm_runtime_use_autosuspend(&pdev->dev); + pm_runtime_set_autosuspend_delay(&pdev->dev, QSPI_AUTOSUSPEND_TIMEOUT); + pm_runtime_enable(&pdev->dev); + + if (!of_property_read_u32(np, "spi-max-frequency", &max_freq)) + qspi->spi_max_frequency = max_freq; + + ret = devm_spi_register_master(&pdev->dev, master); + if (ret) + goto free_master; + + return 0; + +free_master: + spi_master_put(master); + return ret; +} + +static int ti_qspi_remove(struct platform_device *pdev) +{ + struct ti_qspi *qspi = platform_get_drvdata(pdev); + int ret; + + ret = pm_runtime_get_sync(qspi->dev); + if (ret < 0) { + dev_err(qspi->dev, "pm_runtime_get_sync() failed\n"); + return ret; + } + + ti_qspi_write(qspi, QSPI_WC_INT_DISABLE, QSPI_INTR_ENABLE_CLEAR_REG); + + pm_runtime_put(qspi->dev); + pm_runtime_disable(&pdev->dev); + + return 0; +} + +static const struct dev_pm_ops ti_qspi_pm_ops = { + .runtime_resume = ti_qspi_runtime_resume, +}; + +static struct platform_driver ti_qspi_driver = { + .probe = ti_qspi_probe, + .remove = ti_qspi_remove, + .driver = { + .name = "ti-qspi", + .pm = &ti_qspi_pm_ops, + .of_match_table = ti_qspi_match, + } +}; + +module_platform_driver(ti_qspi_driver); + +MODULE_AUTHOR("Sourav Poddar <sourav.poddar@ti.com>"); +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("TI QSPI controller driver"); +MODULE_ALIAS("platform:ti-qspi"); diff --git a/drivers/spi/spi-tle62x0.c b/drivers/spi/spi-tle62x0.c new file mode 100644 index 000000000..daf5aa1c2 --- /dev/null +++ b/drivers/spi/spi-tle62x0.c @@ -0,0 +1,321 @@ +/* + * Support Infineon TLE62x0 driver chips + * + * Copyright (c) 2007 Simtec Electronics + * Ben Dooks, <ben@simtec.co.uk> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/device.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/slab.h> + +#include <linux/spi/spi.h> +#include <linux/spi/tle62x0.h> + + +#define CMD_READ 0x00 +#define CMD_SET 0xff + +#define DIAG_NORMAL 0x03 +#define DIAG_OVERLOAD 0x02 +#define DIAG_OPEN 0x01 +#define DIAG_SHORTGND 0x00 + +struct tle62x0_state { + struct spi_device *us; + struct mutex lock; + unsigned int nr_gpio; + unsigned int gpio_state; + + unsigned char tx_buff[4]; + unsigned char rx_buff[4]; +}; + +static int to_gpio_num(struct device_attribute *attr); + +static inline int tle62x0_write(struct tle62x0_state *st) +{ + unsigned char *buff = st->tx_buff; + unsigned int gpio_state = st->gpio_state; + + buff[0] = CMD_SET; + + if (st->nr_gpio == 16) { + buff[1] = gpio_state >> 8; + buff[2] = gpio_state; + } else { + buff[1] = gpio_state; + } + + dev_dbg(&st->us->dev, "buff %3ph\n", buff); + + return spi_write(st->us, buff, (st->nr_gpio == 16) ? 3 : 2); +} + +static inline int tle62x0_read(struct tle62x0_state *st) +{ + unsigned char *txbuff = st->tx_buff; + struct spi_transfer xfer = { + .tx_buf = txbuff, + .rx_buf = st->rx_buff, + .len = (st->nr_gpio * 2) / 8, + }; + struct spi_message msg; + + txbuff[0] = CMD_READ; + txbuff[1] = 0x00; + txbuff[2] = 0x00; + txbuff[3] = 0x00; + + spi_message_init(&msg); + spi_message_add_tail(&xfer, &msg); + + return spi_sync(st->us, &msg); +} + +static unsigned char *decode_fault(unsigned int fault_code) +{ + fault_code &= 3; + + switch (fault_code) { + case DIAG_NORMAL: + return "N"; + case DIAG_OVERLOAD: + return "V"; + case DIAG_OPEN: + return "O"; + case DIAG_SHORTGND: + return "G"; + } + + return "?"; +} + +static ssize_t tle62x0_status_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct tle62x0_state *st = dev_get_drvdata(dev); + char *bp = buf; + unsigned char *buff = st->rx_buff; + unsigned long fault = 0; + int ptr; + int ret; + + mutex_lock(&st->lock); + ret = tle62x0_read(st); + dev_dbg(dev, "tle62x0_read() returned %d\n", ret); + if (ret < 0) { + mutex_unlock(&st->lock); + return ret; + } + + for (ptr = 0; ptr < (st->nr_gpio * 2)/8; ptr += 1) { + fault <<= 8; + fault |= ((unsigned long)buff[ptr]); + + dev_dbg(dev, "byte %d is %02x\n", ptr, buff[ptr]); + } + + for (ptr = 0; ptr < st->nr_gpio; ptr++) { + bp += sprintf(bp, "%s ", decode_fault(fault >> (ptr * 2))); + } + + *bp++ = '\n'; + + mutex_unlock(&st->lock); + return bp - buf; +} + +static DEVICE_ATTR(status_show, S_IRUGO, tle62x0_status_show, NULL); + +static ssize_t tle62x0_gpio_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct tle62x0_state *st = dev_get_drvdata(dev); + int gpio_num = to_gpio_num(attr); + int value; + + mutex_lock(&st->lock); + value = (st->gpio_state >> gpio_num) & 1; + mutex_unlock(&st->lock); + + return snprintf(buf, PAGE_SIZE, "%d", value); +} + +static ssize_t tle62x0_gpio_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t len) +{ + struct tle62x0_state *st = dev_get_drvdata(dev); + int gpio_num = to_gpio_num(attr); + unsigned long val; + char *endp; + + val = simple_strtoul(buf, &endp, 0); + if (buf == endp) + return -EINVAL; + + dev_dbg(dev, "setting gpio %d to %ld\n", gpio_num, val); + + mutex_lock(&st->lock); + + if (val) + st->gpio_state |= 1 << gpio_num; + else + st->gpio_state &= ~(1 << gpio_num); + + tle62x0_write(st); + mutex_unlock(&st->lock); + + return len; +} + +static DEVICE_ATTR(gpio1, S_IWUSR|S_IRUGO, + tle62x0_gpio_show, tle62x0_gpio_store); +static DEVICE_ATTR(gpio2, S_IWUSR|S_IRUGO, + tle62x0_gpio_show, tle62x0_gpio_store); +static DEVICE_ATTR(gpio3, S_IWUSR|S_IRUGO, + tle62x0_gpio_show, tle62x0_gpio_store); +static DEVICE_ATTR(gpio4, S_IWUSR|S_IRUGO, + tle62x0_gpio_show, tle62x0_gpio_store); +static DEVICE_ATTR(gpio5, S_IWUSR|S_IRUGO, + tle62x0_gpio_show, tle62x0_gpio_store); +static DEVICE_ATTR(gpio6, S_IWUSR|S_IRUGO, + tle62x0_gpio_show, tle62x0_gpio_store); +static DEVICE_ATTR(gpio7, S_IWUSR|S_IRUGO, + tle62x0_gpio_show, tle62x0_gpio_store); +static DEVICE_ATTR(gpio8, S_IWUSR|S_IRUGO, + tle62x0_gpio_show, tle62x0_gpio_store); +static DEVICE_ATTR(gpio9, S_IWUSR|S_IRUGO, + tle62x0_gpio_show, tle62x0_gpio_store); +static DEVICE_ATTR(gpio10, S_IWUSR|S_IRUGO, + tle62x0_gpio_show, tle62x0_gpio_store); +static DEVICE_ATTR(gpio11, S_IWUSR|S_IRUGO, + tle62x0_gpio_show, tle62x0_gpio_store); +static DEVICE_ATTR(gpio12, S_IWUSR|S_IRUGO, + tle62x0_gpio_show, tle62x0_gpio_store); +static DEVICE_ATTR(gpio13, S_IWUSR|S_IRUGO, + tle62x0_gpio_show, tle62x0_gpio_store); +static DEVICE_ATTR(gpio14, S_IWUSR|S_IRUGO, + tle62x0_gpio_show, tle62x0_gpio_store); +static DEVICE_ATTR(gpio15, S_IWUSR|S_IRUGO, + tle62x0_gpio_show, tle62x0_gpio_store); +static DEVICE_ATTR(gpio16, S_IWUSR|S_IRUGO, + tle62x0_gpio_show, tle62x0_gpio_store); + +static struct device_attribute *gpio_attrs[] = { + [0] = &dev_attr_gpio1, + [1] = &dev_attr_gpio2, + [2] = &dev_attr_gpio3, + [3] = &dev_attr_gpio4, + [4] = &dev_attr_gpio5, + [5] = &dev_attr_gpio6, + [6] = &dev_attr_gpio7, + [7] = &dev_attr_gpio8, + [8] = &dev_attr_gpio9, + [9] = &dev_attr_gpio10, + [10] = &dev_attr_gpio11, + [11] = &dev_attr_gpio12, + [12] = &dev_attr_gpio13, + [13] = &dev_attr_gpio14, + [14] = &dev_attr_gpio15, + [15] = &dev_attr_gpio16 +}; + +static int to_gpio_num(struct device_attribute *attr) +{ + int ptr; + + for (ptr = 0; ptr < ARRAY_SIZE(gpio_attrs); ptr++) { + if (gpio_attrs[ptr] == attr) + return ptr; + } + + return -1; +} + +static int tle62x0_probe(struct spi_device *spi) +{ + struct tle62x0_state *st; + struct tle62x0_pdata *pdata; + int ptr; + int ret; + + pdata = dev_get_platdata(&spi->dev); + if (pdata == NULL) { + dev_err(&spi->dev, "no device data specified\n"); + return -EINVAL; + } + + st = kzalloc(sizeof(struct tle62x0_state), GFP_KERNEL); + if (st == NULL) + return -ENOMEM; + + st->us = spi; + st->nr_gpio = pdata->gpio_count; + st->gpio_state = pdata->init_state; + + mutex_init(&st->lock); + + ret = device_create_file(&spi->dev, &dev_attr_status_show); + if (ret) { + dev_err(&spi->dev, "cannot create status attribute\n"); + goto err_status; + } + + for (ptr = 0; ptr < pdata->gpio_count; ptr++) { + ret = device_create_file(&spi->dev, gpio_attrs[ptr]); + if (ret) { + dev_err(&spi->dev, "cannot create gpio attribute\n"); + goto err_gpios; + } + } + + /* tle62x0_write(st); */ + spi_set_drvdata(spi, st); + return 0; + + err_gpios: + while (--ptr >= 0) + device_remove_file(&spi->dev, gpio_attrs[ptr]); + + device_remove_file(&spi->dev, &dev_attr_status_show); + + err_status: + kfree(st); + return ret; +} + +static int tle62x0_remove(struct spi_device *spi) +{ + struct tle62x0_state *st = spi_get_drvdata(spi); + int ptr; + + for (ptr = 0; ptr < st->nr_gpio; ptr++) + device_remove_file(&spi->dev, gpio_attrs[ptr]); + + device_remove_file(&spi->dev, &dev_attr_status_show); + kfree(st); + return 0; +} + +static struct spi_driver tle62x0_driver = { + .driver = { + .name = "tle62x0", + .owner = THIS_MODULE, + }, + .probe = tle62x0_probe, + .remove = tle62x0_remove, +}; + +module_spi_driver(tle62x0_driver); + +MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>"); +MODULE_DESCRIPTION("TLE62x0 SPI driver"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("spi:tle62x0"); diff --git a/drivers/spi/spi-topcliff-pch.c b/drivers/spi/spi-topcliff-pch.c new file mode 100644 index 000000000..93dfcee0f --- /dev/null +++ b/drivers/spi/spi-topcliff-pch.c @@ -0,0 +1,1754 @@ +/* + * SPI bus driver for the Topcliff PCH used by Intel SoCs + * + * Copyright (C) 2011 LAPIS Semiconductor Co., Ltd. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; version 2 of the License. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/delay.h> +#include <linux/pci.h> +#include <linux/wait.h> +#include <linux/spi/spi.h> +#include <linux/interrupt.h> +#include <linux/sched.h> +#include <linux/spi/spidev.h> +#include <linux/module.h> +#include <linux/device.h> +#include <linux/platform_device.h> + +#include <linux/dmaengine.h> +#include <linux/pch_dma.h> + +/* Register offsets */ +#define PCH_SPCR 0x00 /* SPI control register */ +#define PCH_SPBRR 0x04 /* SPI baud rate register */ +#define PCH_SPSR 0x08 /* SPI status register */ +#define PCH_SPDWR 0x0C /* SPI write data register */ +#define PCH_SPDRR 0x10 /* SPI read data register */ +#define PCH_SSNXCR 0x18 /* SSN Expand Control Register */ +#define PCH_SRST 0x1C /* SPI reset register */ +#define PCH_ADDRESS_SIZE 0x20 + +#define PCH_SPSR_TFD 0x000007C0 +#define PCH_SPSR_RFD 0x0000F800 + +#define PCH_READABLE(x) (((x) & PCH_SPSR_RFD)>>11) +#define PCH_WRITABLE(x) (((x) & PCH_SPSR_TFD)>>6) + +#define PCH_RX_THOLD 7 +#define PCH_RX_THOLD_MAX 15 + +#define PCH_TX_THOLD 2 + +#define PCH_MAX_BAUDRATE 5000000 +#define PCH_MAX_FIFO_DEPTH 16 + +#define STATUS_RUNNING 1 +#define STATUS_EXITING 2 +#define PCH_SLEEP_TIME 10 + +#define SSN_LOW 0x02U +#define SSN_HIGH 0x03U +#define SSN_NO_CONTROL 0x00U +#define PCH_MAX_CS 0xFF +#define PCI_DEVICE_ID_GE_SPI 0x8816 + +#define SPCR_SPE_BIT (1 << 0) +#define SPCR_MSTR_BIT (1 << 1) +#define SPCR_LSBF_BIT (1 << 4) +#define SPCR_CPHA_BIT (1 << 5) +#define SPCR_CPOL_BIT (1 << 6) +#define SPCR_TFIE_BIT (1 << 8) +#define SPCR_RFIE_BIT (1 << 9) +#define SPCR_FIE_BIT (1 << 10) +#define SPCR_ORIE_BIT (1 << 11) +#define SPCR_MDFIE_BIT (1 << 12) +#define SPCR_FICLR_BIT (1 << 24) +#define SPSR_TFI_BIT (1 << 0) +#define SPSR_RFI_BIT (1 << 1) +#define SPSR_FI_BIT (1 << 2) +#define SPSR_ORF_BIT (1 << 3) +#define SPBRR_SIZE_BIT (1 << 10) + +#define PCH_ALL (SPCR_TFIE_BIT|SPCR_RFIE_BIT|SPCR_FIE_BIT|\ + SPCR_ORIE_BIT|SPCR_MDFIE_BIT) + +#define SPCR_RFIC_FIELD 20 +#define SPCR_TFIC_FIELD 16 + +#define MASK_SPBRR_SPBR_BITS ((1 << 10) - 1) +#define MASK_RFIC_SPCR_BITS (0xf << SPCR_RFIC_FIELD) +#define MASK_TFIC_SPCR_BITS (0xf << SPCR_TFIC_FIELD) + +#define PCH_CLOCK_HZ 50000000 +#define PCH_MAX_SPBR 1023 + +/* Definition for ML7213/ML7223/ML7831 by LAPIS Semiconductor */ +#define PCI_VENDOR_ID_ROHM 0x10DB +#define PCI_DEVICE_ID_ML7213_SPI 0x802c +#define PCI_DEVICE_ID_ML7223_SPI 0x800F +#define PCI_DEVICE_ID_ML7831_SPI 0x8816 + +/* + * Set the number of SPI instance max + * Intel EG20T PCH : 1ch + * LAPIS Semiconductor ML7213 IOH : 2ch + * LAPIS Semiconductor ML7223 IOH : 1ch + * LAPIS Semiconductor ML7831 IOH : 1ch +*/ +#define PCH_SPI_MAX_DEV 2 + +#define PCH_BUF_SIZE 4096 +#define PCH_DMA_TRANS_SIZE 12 + +static int use_dma = 1; + +struct pch_spi_dma_ctrl { + struct dma_async_tx_descriptor *desc_tx; + struct dma_async_tx_descriptor *desc_rx; + struct pch_dma_slave param_tx; + struct pch_dma_slave param_rx; + struct dma_chan *chan_tx; + struct dma_chan *chan_rx; + struct scatterlist *sg_tx_p; + struct scatterlist *sg_rx_p; + struct scatterlist sg_tx; + struct scatterlist sg_rx; + int nent; + void *tx_buf_virt; + void *rx_buf_virt; + dma_addr_t tx_buf_dma; + dma_addr_t rx_buf_dma; +}; +/** + * struct pch_spi_data - Holds the SPI channel specific details + * @io_remap_addr: The remapped PCI base address + * @master: Pointer to the SPI master structure + * @work: Reference to work queue handler + * @wk: Workqueue for carrying out execution of the + * requests + * @wait: Wait queue for waking up upon receiving an + * interrupt. + * @transfer_complete: Status of SPI Transfer + * @bcurrent_msg_processing: Status flag for message processing + * @lock: Lock for protecting this structure + * @queue: SPI Message queue + * @status: Status of the SPI driver + * @bpw_len: Length of data to be transferred in bits per + * word + * @transfer_active: Flag showing active transfer + * @tx_index: Transmit data count; for bookkeeping during + * transfer + * @rx_index: Receive data count; for bookkeeping during + * transfer + * @tx_buff: Buffer for data to be transmitted + * @rx_index: Buffer for Received data + * @n_curnt_chip: The chip number that this SPI driver currently + * operates on + * @current_chip: Reference to the current chip that this SPI + * driver currently operates on + * @current_msg: The current message that this SPI driver is + * handling + * @cur_trans: The current transfer that this SPI driver is + * handling + * @board_dat: Reference to the SPI device data structure + * @plat_dev: platform_device structure + * @ch: SPI channel number + * @irq_reg_sts: Status of IRQ registration + */ +struct pch_spi_data { + void __iomem *io_remap_addr; + unsigned long io_base_addr; + struct spi_master *master; + struct work_struct work; + struct workqueue_struct *wk; + wait_queue_head_t wait; + u8 transfer_complete; + u8 bcurrent_msg_processing; + spinlock_t lock; + struct list_head queue; + u8 status; + u32 bpw_len; + u8 transfer_active; + u32 tx_index; + u32 rx_index; + u16 *pkt_tx_buff; + u16 *pkt_rx_buff; + u8 n_curnt_chip; + struct spi_device *current_chip; + struct spi_message *current_msg; + struct spi_transfer *cur_trans; + struct pch_spi_board_data *board_dat; + struct platform_device *plat_dev; + int ch; + struct pch_spi_dma_ctrl dma; + int use_dma; + u8 irq_reg_sts; + int save_total_len; +}; + +/** + * struct pch_spi_board_data - Holds the SPI device specific details + * @pdev: Pointer to the PCI device + * @suspend_sts: Status of suspend + * @num: The number of SPI device instance + */ +struct pch_spi_board_data { + struct pci_dev *pdev; + u8 suspend_sts; + int num; +}; + +struct pch_pd_dev_save { + int num; + struct platform_device *pd_save[PCH_SPI_MAX_DEV]; + struct pch_spi_board_data *board_dat; +}; + +static const struct pci_device_id pch_spi_pcidev_id[] = { + { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_GE_SPI), 1, }, + { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7213_SPI), 2, }, + { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7223_SPI), 1, }, + { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7831_SPI), 1, }, + { } +}; + +/** + * pch_spi_writereg() - Performs register writes + * @master: Pointer to struct spi_master. + * @idx: Register offset. + * @val: Value to be written to register. + */ +static inline void pch_spi_writereg(struct spi_master *master, int idx, u32 val) +{ + struct pch_spi_data *data = spi_master_get_devdata(master); + iowrite32(val, (data->io_remap_addr + idx)); +} + +/** + * pch_spi_readreg() - Performs register reads + * @master: Pointer to struct spi_master. + * @idx: Register offset. + */ +static inline u32 pch_spi_readreg(struct spi_master *master, int idx) +{ + struct pch_spi_data *data = spi_master_get_devdata(master); + return ioread32(data->io_remap_addr + idx); +} + +static inline void pch_spi_setclr_reg(struct spi_master *master, int idx, + u32 set, u32 clr) +{ + u32 tmp = pch_spi_readreg(master, idx); + tmp = (tmp & ~clr) | set; + pch_spi_writereg(master, idx, tmp); +} + +static void pch_spi_set_master_mode(struct spi_master *master) +{ + pch_spi_setclr_reg(master, PCH_SPCR, SPCR_MSTR_BIT, 0); +} + +/** + * pch_spi_clear_fifo() - Clears the Transmit and Receive FIFOs + * @master: Pointer to struct spi_master. + */ +static void pch_spi_clear_fifo(struct spi_master *master) +{ + pch_spi_setclr_reg(master, PCH_SPCR, SPCR_FICLR_BIT, 0); + pch_spi_setclr_reg(master, PCH_SPCR, 0, SPCR_FICLR_BIT); +} + +static void pch_spi_handler_sub(struct pch_spi_data *data, u32 reg_spsr_val, + void __iomem *io_remap_addr) +{ + u32 n_read, tx_index, rx_index, bpw_len; + u16 *pkt_rx_buffer, *pkt_tx_buff; + int read_cnt; + u32 reg_spcr_val; + void __iomem *spsr; + void __iomem *spdrr; + void __iomem *spdwr; + + spsr = io_remap_addr + PCH_SPSR; + iowrite32(reg_spsr_val, spsr); + + if (data->transfer_active) { + rx_index = data->rx_index; + tx_index = data->tx_index; + bpw_len = data->bpw_len; + pkt_rx_buffer = data->pkt_rx_buff; + pkt_tx_buff = data->pkt_tx_buff; + + spdrr = io_remap_addr + PCH_SPDRR; + spdwr = io_remap_addr + PCH_SPDWR; + + n_read = PCH_READABLE(reg_spsr_val); + + for (read_cnt = 0; (read_cnt < n_read); read_cnt++) { + pkt_rx_buffer[rx_index++] = ioread32(spdrr); + if (tx_index < bpw_len) + iowrite32(pkt_tx_buff[tx_index++], spdwr); + } + + /* disable RFI if not needed */ + if ((bpw_len - rx_index) <= PCH_MAX_FIFO_DEPTH) { + reg_spcr_val = ioread32(io_remap_addr + PCH_SPCR); + reg_spcr_val &= ~SPCR_RFIE_BIT; /* disable RFI */ + + /* reset rx threshold */ + reg_spcr_val &= ~MASK_RFIC_SPCR_BITS; + reg_spcr_val |= (PCH_RX_THOLD_MAX << SPCR_RFIC_FIELD); + + iowrite32(reg_spcr_val, (io_remap_addr + PCH_SPCR)); + } + + /* update counts */ + data->tx_index = tx_index; + data->rx_index = rx_index; + + /* if transfer complete interrupt */ + if (reg_spsr_val & SPSR_FI_BIT) { + if ((tx_index == bpw_len) && (rx_index == tx_index)) { + /* disable interrupts */ + pch_spi_setclr_reg(data->master, PCH_SPCR, 0, + PCH_ALL); + + /* transfer is completed; + inform pch_spi_process_messages */ + data->transfer_complete = true; + data->transfer_active = false; + wake_up(&data->wait); + } else { + dev_vdbg(&data->master->dev, + "%s : Transfer is not completed", + __func__); + } + } + } +} + +/** + * pch_spi_handler() - Interrupt handler + * @irq: The interrupt number. + * @dev_id: Pointer to struct pch_spi_board_data. + */ +static irqreturn_t pch_spi_handler(int irq, void *dev_id) +{ + u32 reg_spsr_val; + void __iomem *spsr; + void __iomem *io_remap_addr; + irqreturn_t ret = IRQ_NONE; + struct pch_spi_data *data = dev_id; + struct pch_spi_board_data *board_dat = data->board_dat; + + if (board_dat->suspend_sts) { + dev_dbg(&board_dat->pdev->dev, + "%s returning due to suspend\n", __func__); + return IRQ_NONE; + } + + io_remap_addr = data->io_remap_addr; + spsr = io_remap_addr + PCH_SPSR; + + reg_spsr_val = ioread32(spsr); + + if (reg_spsr_val & SPSR_ORF_BIT) { + dev_err(&board_dat->pdev->dev, "%s Over run error\n", __func__); + if (data->current_msg->complete) { + data->transfer_complete = true; + data->current_msg->status = -EIO; + data->current_msg->complete(data->current_msg->context); + data->bcurrent_msg_processing = false; + data->current_msg = NULL; + data->cur_trans = NULL; + } + } + + if (data->use_dma) + return IRQ_NONE; + + /* Check if the interrupt is for SPI device */ + if (reg_spsr_val & (SPSR_FI_BIT | SPSR_RFI_BIT)) { + pch_spi_handler_sub(data, reg_spsr_val, io_remap_addr); + ret = IRQ_HANDLED; + } + + dev_dbg(&board_dat->pdev->dev, "%s EXIT return value=%d\n", + __func__, ret); + + return ret; +} + +/** + * pch_spi_set_baud_rate() - Sets SPBR field in SPBRR + * @master: Pointer to struct spi_master. + * @speed_hz: Baud rate. + */ +static void pch_spi_set_baud_rate(struct spi_master *master, u32 speed_hz) +{ + u32 n_spbr = PCH_CLOCK_HZ / (speed_hz * 2); + + /* if baud rate is less than we can support limit it */ + if (n_spbr > PCH_MAX_SPBR) + n_spbr = PCH_MAX_SPBR; + + pch_spi_setclr_reg(master, PCH_SPBRR, n_spbr, MASK_SPBRR_SPBR_BITS); +} + +/** + * pch_spi_set_bits_per_word() - Sets SIZE field in SPBRR + * @master: Pointer to struct spi_master. + * @bits_per_word: Bits per word for SPI transfer. + */ +static void pch_spi_set_bits_per_word(struct spi_master *master, + u8 bits_per_word) +{ + if (bits_per_word == 8) + pch_spi_setclr_reg(master, PCH_SPBRR, 0, SPBRR_SIZE_BIT); + else + pch_spi_setclr_reg(master, PCH_SPBRR, SPBRR_SIZE_BIT, 0); +} + +/** + * pch_spi_setup_transfer() - Configures the PCH SPI hardware for transfer + * @spi: Pointer to struct spi_device. + */ +static void pch_spi_setup_transfer(struct spi_device *spi) +{ + u32 flags = 0; + + dev_dbg(&spi->dev, "%s SPBRR content =%x setting baud rate=%d\n", + __func__, pch_spi_readreg(spi->master, PCH_SPBRR), + spi->max_speed_hz); + pch_spi_set_baud_rate(spi->master, spi->max_speed_hz); + + /* set bits per word */ + pch_spi_set_bits_per_word(spi->master, spi->bits_per_word); + + if (!(spi->mode & SPI_LSB_FIRST)) + flags |= SPCR_LSBF_BIT; + if (spi->mode & SPI_CPOL) + flags |= SPCR_CPOL_BIT; + if (spi->mode & SPI_CPHA) + flags |= SPCR_CPHA_BIT; + pch_spi_setclr_reg(spi->master, PCH_SPCR, flags, + (SPCR_LSBF_BIT | SPCR_CPOL_BIT | SPCR_CPHA_BIT)); + + /* Clear the FIFO by toggling FICLR to 1 and back to 0 */ + pch_spi_clear_fifo(spi->master); +} + +/** + * pch_spi_reset() - Clears SPI registers + * @master: Pointer to struct spi_master. + */ +static void pch_spi_reset(struct spi_master *master) +{ + /* write 1 to reset SPI */ + pch_spi_writereg(master, PCH_SRST, 0x1); + + /* clear reset */ + pch_spi_writereg(master, PCH_SRST, 0x0); +} + +static int pch_spi_transfer(struct spi_device *pspi, struct spi_message *pmsg) +{ + + struct spi_transfer *transfer; + struct pch_spi_data *data = spi_master_get_devdata(pspi->master); + int retval; + unsigned long flags; + + spin_lock_irqsave(&data->lock, flags); + /* validate Tx/Rx buffers and Transfer length */ + list_for_each_entry(transfer, &pmsg->transfers, transfer_list) { + if (!transfer->tx_buf && !transfer->rx_buf) { + dev_err(&pspi->dev, + "%s Tx and Rx buffer NULL\n", __func__); + retval = -EINVAL; + goto err_return_spinlock; + } + + if (!transfer->len) { + dev_err(&pspi->dev, "%s Transfer length invalid\n", + __func__); + retval = -EINVAL; + goto err_return_spinlock; + } + + dev_dbg(&pspi->dev, + "%s Tx/Rx buffer valid. Transfer length valid\n", + __func__); + } + spin_unlock_irqrestore(&data->lock, flags); + + /* We won't process any messages if we have been asked to terminate */ + if (data->status == STATUS_EXITING) { + dev_err(&pspi->dev, "%s status = STATUS_EXITING.\n", __func__); + retval = -ESHUTDOWN; + goto err_out; + } + + /* If suspended ,return -EINVAL */ + if (data->board_dat->suspend_sts) { + dev_err(&pspi->dev, "%s suspend; returning EINVAL\n", __func__); + retval = -EINVAL; + goto err_out; + } + + /* set status of message */ + pmsg->actual_length = 0; + dev_dbg(&pspi->dev, "%s - pmsg->status =%d\n", __func__, pmsg->status); + + pmsg->status = -EINPROGRESS; + spin_lock_irqsave(&data->lock, flags); + /* add message to queue */ + list_add_tail(&pmsg->queue, &data->queue); + spin_unlock_irqrestore(&data->lock, flags); + + dev_dbg(&pspi->dev, "%s - Invoked list_add_tail\n", __func__); + + /* schedule work queue to run */ + queue_work(data->wk, &data->work); + dev_dbg(&pspi->dev, "%s - Invoked queue work\n", __func__); + + retval = 0; + +err_out: + dev_dbg(&pspi->dev, "%s RETURN=%d\n", __func__, retval); + return retval; +err_return_spinlock: + dev_dbg(&pspi->dev, "%s RETURN=%d\n", __func__, retval); + spin_unlock_irqrestore(&data->lock, flags); + return retval; +} + +static inline void pch_spi_select_chip(struct pch_spi_data *data, + struct spi_device *pspi) +{ + if (data->current_chip != NULL) { + if (pspi->chip_select != data->n_curnt_chip) { + dev_dbg(&pspi->dev, "%s : different slave\n", __func__); + data->current_chip = NULL; + } + } + + data->current_chip = pspi; + + data->n_curnt_chip = data->current_chip->chip_select; + + dev_dbg(&pspi->dev, "%s :Invoking pch_spi_setup_transfer\n", __func__); + pch_spi_setup_transfer(pspi); +} + +static void pch_spi_set_tx(struct pch_spi_data *data, int *bpw) +{ + int size; + u32 n_writes; + int j; + struct spi_message *pmsg, *tmp; + const u8 *tx_buf; + const u16 *tx_sbuf; + + /* set baud rate if needed */ + if (data->cur_trans->speed_hz) { + dev_dbg(&data->master->dev, "%s:setting baud rate\n", __func__); + pch_spi_set_baud_rate(data->master, data->cur_trans->speed_hz); + } + + /* set bits per word if needed */ + if (data->cur_trans->bits_per_word && + (data->current_msg->spi->bits_per_word != data->cur_trans->bits_per_word)) { + dev_dbg(&data->master->dev, "%s:set bits per word\n", __func__); + pch_spi_set_bits_per_word(data->master, + data->cur_trans->bits_per_word); + *bpw = data->cur_trans->bits_per_word; + } else { + *bpw = data->current_msg->spi->bits_per_word; + } + + /* reset Tx/Rx index */ + data->tx_index = 0; + data->rx_index = 0; + + data->bpw_len = data->cur_trans->len / (*bpw / 8); + + /* find alloc size */ + size = data->cur_trans->len * sizeof(*data->pkt_tx_buff); + + /* allocate memory for pkt_tx_buff & pkt_rx_buffer */ + data->pkt_tx_buff = kzalloc(size, GFP_KERNEL); + if (data->pkt_tx_buff != NULL) { + data->pkt_rx_buff = kzalloc(size, GFP_KERNEL); + if (!data->pkt_rx_buff) + kfree(data->pkt_tx_buff); + } + + if (!data->pkt_rx_buff) { + /* flush queue and set status of all transfers to -ENOMEM */ + dev_err(&data->master->dev, "%s :kzalloc failed\n", __func__); + list_for_each_entry_safe(pmsg, tmp, data->queue.next, queue) { + pmsg->status = -ENOMEM; + + if (pmsg->complete) + pmsg->complete(pmsg->context); + + /* delete from queue */ + list_del_init(&pmsg->queue); + } + return; + } + + /* copy Tx Data */ + if (data->cur_trans->tx_buf != NULL) { + if (*bpw == 8) { + tx_buf = data->cur_trans->tx_buf; + for (j = 0; j < data->bpw_len; j++) + data->pkt_tx_buff[j] = *tx_buf++; + } else { + tx_sbuf = data->cur_trans->tx_buf; + for (j = 0; j < data->bpw_len; j++) + data->pkt_tx_buff[j] = *tx_sbuf++; + } + } + + /* if len greater than PCH_MAX_FIFO_DEPTH, write 16,else len bytes */ + n_writes = data->bpw_len; + if (n_writes > PCH_MAX_FIFO_DEPTH) + n_writes = PCH_MAX_FIFO_DEPTH; + + dev_dbg(&data->master->dev, "\n%s:Pulling down SSN low - writing " + "0x2 to SSNXCR\n", __func__); + pch_spi_writereg(data->master, PCH_SSNXCR, SSN_LOW); + + for (j = 0; j < n_writes; j++) + pch_spi_writereg(data->master, PCH_SPDWR, data->pkt_tx_buff[j]); + + /* update tx_index */ + data->tx_index = j; + + /* reset transfer complete flag */ + data->transfer_complete = false; + data->transfer_active = true; +} + +static void pch_spi_nomore_transfer(struct pch_spi_data *data) +{ + struct spi_message *pmsg, *tmp; + dev_dbg(&data->master->dev, "%s called\n", __func__); + /* Invoke complete callback + * [To the spi core..indicating end of transfer] */ + data->current_msg->status = 0; + + if (data->current_msg->complete) { + dev_dbg(&data->master->dev, + "%s:Invoking callback of SPI core\n", __func__); + data->current_msg->complete(data->current_msg->context); + } + + /* update status in global variable */ + data->bcurrent_msg_processing = false; + + dev_dbg(&data->master->dev, + "%s:data->bcurrent_msg_processing = false\n", __func__); + + data->current_msg = NULL; + data->cur_trans = NULL; + + /* check if we have items in list and not suspending + * return 1 if list empty */ + if ((list_empty(&data->queue) == 0) && + (!data->board_dat->suspend_sts) && + (data->status != STATUS_EXITING)) { + /* We have some more work to do (either there is more tranint + * bpw;sfer requests in the current message or there are + *more messages) + */ + dev_dbg(&data->master->dev, "%s:Invoke queue_work\n", __func__); + queue_work(data->wk, &data->work); + } else if (data->board_dat->suspend_sts || + data->status == STATUS_EXITING) { + dev_dbg(&data->master->dev, + "%s suspend/remove initiated, flushing queue\n", + __func__); + list_for_each_entry_safe(pmsg, tmp, data->queue.next, queue) { + pmsg->status = -EIO; + + if (pmsg->complete) + pmsg->complete(pmsg->context); + + /* delete from queue */ + list_del_init(&pmsg->queue); + } + } +} + +static void pch_spi_set_ir(struct pch_spi_data *data) +{ + /* enable interrupts, set threshold, enable SPI */ + if ((data->bpw_len) > PCH_MAX_FIFO_DEPTH) + /* set receive threshold to PCH_RX_THOLD */ + pch_spi_setclr_reg(data->master, PCH_SPCR, + PCH_RX_THOLD << SPCR_RFIC_FIELD | + SPCR_FIE_BIT | SPCR_RFIE_BIT | + SPCR_ORIE_BIT | SPCR_SPE_BIT, + MASK_RFIC_SPCR_BITS | PCH_ALL); + else + /* set receive threshold to maximum */ + pch_spi_setclr_reg(data->master, PCH_SPCR, + PCH_RX_THOLD_MAX << SPCR_RFIC_FIELD | + SPCR_FIE_BIT | SPCR_ORIE_BIT | + SPCR_SPE_BIT, + MASK_RFIC_SPCR_BITS | PCH_ALL); + + /* Wait until the transfer completes; go to sleep after + initiating the transfer. */ + dev_dbg(&data->master->dev, + "%s:waiting for transfer to get over\n", __func__); + + wait_event_interruptible(data->wait, data->transfer_complete); + + /* clear all interrupts */ + pch_spi_writereg(data->master, PCH_SPSR, + pch_spi_readreg(data->master, PCH_SPSR)); + /* Disable interrupts and SPI transfer */ + pch_spi_setclr_reg(data->master, PCH_SPCR, 0, PCH_ALL | SPCR_SPE_BIT); + /* clear FIFO */ + pch_spi_clear_fifo(data->master); +} + +static void pch_spi_copy_rx_data(struct pch_spi_data *data, int bpw) +{ + int j; + u8 *rx_buf; + u16 *rx_sbuf; + + /* copy Rx Data */ + if (!data->cur_trans->rx_buf) + return; + + if (bpw == 8) { + rx_buf = data->cur_trans->rx_buf; + for (j = 0; j < data->bpw_len; j++) + *rx_buf++ = data->pkt_rx_buff[j] & 0xFF; + } else { + rx_sbuf = data->cur_trans->rx_buf; + for (j = 0; j < data->bpw_len; j++) + *rx_sbuf++ = data->pkt_rx_buff[j]; + } +} + +static void pch_spi_copy_rx_data_for_dma(struct pch_spi_data *data, int bpw) +{ + int j; + u8 *rx_buf; + u16 *rx_sbuf; + const u8 *rx_dma_buf; + const u16 *rx_dma_sbuf; + + /* copy Rx Data */ + if (!data->cur_trans->rx_buf) + return; + + if (bpw == 8) { + rx_buf = data->cur_trans->rx_buf; + rx_dma_buf = data->dma.rx_buf_virt; + for (j = 0; j < data->bpw_len; j++) + *rx_buf++ = *rx_dma_buf++ & 0xFF; + data->cur_trans->rx_buf = rx_buf; + } else { + rx_sbuf = data->cur_trans->rx_buf; + rx_dma_sbuf = data->dma.rx_buf_virt; + for (j = 0; j < data->bpw_len; j++) + *rx_sbuf++ = *rx_dma_sbuf++; + data->cur_trans->rx_buf = rx_sbuf; + } +} + +static int pch_spi_start_transfer(struct pch_spi_data *data) +{ + struct pch_spi_dma_ctrl *dma; + unsigned long flags; + int rtn; + + dma = &data->dma; + + spin_lock_irqsave(&data->lock, flags); + + /* disable interrupts, SPI set enable */ + pch_spi_setclr_reg(data->master, PCH_SPCR, SPCR_SPE_BIT, PCH_ALL); + + spin_unlock_irqrestore(&data->lock, flags); + + /* Wait until the transfer completes; go to sleep after + initiating the transfer. */ + dev_dbg(&data->master->dev, + "%s:waiting for transfer to get over\n", __func__); + rtn = wait_event_interruptible_timeout(data->wait, + data->transfer_complete, + msecs_to_jiffies(2 * HZ)); + if (!rtn) + dev_err(&data->master->dev, + "%s wait-event timeout\n", __func__); + + dma_sync_sg_for_cpu(&data->master->dev, dma->sg_rx_p, dma->nent, + DMA_FROM_DEVICE); + + dma_sync_sg_for_cpu(&data->master->dev, dma->sg_tx_p, dma->nent, + DMA_FROM_DEVICE); + memset(data->dma.tx_buf_virt, 0, PAGE_SIZE); + + async_tx_ack(dma->desc_rx); + async_tx_ack(dma->desc_tx); + kfree(dma->sg_tx_p); + kfree(dma->sg_rx_p); + + spin_lock_irqsave(&data->lock, flags); + + /* clear fifo threshold, disable interrupts, disable SPI transfer */ + pch_spi_setclr_reg(data->master, PCH_SPCR, 0, + MASK_RFIC_SPCR_BITS | MASK_TFIC_SPCR_BITS | PCH_ALL | + SPCR_SPE_BIT); + /* clear all interrupts */ + pch_spi_writereg(data->master, PCH_SPSR, + pch_spi_readreg(data->master, PCH_SPSR)); + /* clear FIFO */ + pch_spi_clear_fifo(data->master); + + spin_unlock_irqrestore(&data->lock, flags); + + return rtn; +} + +static void pch_dma_rx_complete(void *arg) +{ + struct pch_spi_data *data = arg; + + /* transfer is completed;inform pch_spi_process_messages_dma */ + data->transfer_complete = true; + wake_up_interruptible(&data->wait); +} + +static bool pch_spi_filter(struct dma_chan *chan, void *slave) +{ + struct pch_dma_slave *param = slave; + + if ((chan->chan_id == param->chan_id) && + (param->dma_dev == chan->device->dev)) { + chan->private = param; + return true; + } else { + return false; + } +} + +static void pch_spi_request_dma(struct pch_spi_data *data, int bpw) +{ + dma_cap_mask_t mask; + struct dma_chan *chan; + struct pci_dev *dma_dev; + struct pch_dma_slave *param; + struct pch_spi_dma_ctrl *dma; + unsigned int width; + + if (bpw == 8) + width = PCH_DMA_WIDTH_1_BYTE; + else + width = PCH_DMA_WIDTH_2_BYTES; + + dma = &data->dma; + dma_cap_zero(mask); + dma_cap_set(DMA_SLAVE, mask); + + /* Get DMA's dev information */ + dma_dev = pci_get_slot(data->board_dat->pdev->bus, + PCI_DEVFN(PCI_SLOT(data->board_dat->pdev->devfn), 0)); + + /* Set Tx DMA */ + param = &dma->param_tx; + param->dma_dev = &dma_dev->dev; + param->chan_id = data->ch * 2; /* Tx = 0, 2 */; + param->tx_reg = data->io_base_addr + PCH_SPDWR; + param->width = width; + chan = dma_request_channel(mask, pch_spi_filter, param); + if (!chan) { + dev_err(&data->master->dev, + "ERROR: dma_request_channel FAILS(Tx)\n"); + data->use_dma = 0; + return; + } + dma->chan_tx = chan; + + /* Set Rx DMA */ + param = &dma->param_rx; + param->dma_dev = &dma_dev->dev; + param->chan_id = data->ch * 2 + 1; /* Rx = Tx + 1 */; + param->rx_reg = data->io_base_addr + PCH_SPDRR; + param->width = width; + chan = dma_request_channel(mask, pch_spi_filter, param); + if (!chan) { + dev_err(&data->master->dev, + "ERROR: dma_request_channel FAILS(Rx)\n"); + dma_release_channel(dma->chan_tx); + dma->chan_tx = NULL; + data->use_dma = 0; + return; + } + dma->chan_rx = chan; +} + +static void pch_spi_release_dma(struct pch_spi_data *data) +{ + struct pch_spi_dma_ctrl *dma; + + dma = &data->dma; + if (dma->chan_tx) { + dma_release_channel(dma->chan_tx); + dma->chan_tx = NULL; + } + if (dma->chan_rx) { + dma_release_channel(dma->chan_rx); + dma->chan_rx = NULL; + } + return; +} + +static void pch_spi_handle_dma(struct pch_spi_data *data, int *bpw) +{ + const u8 *tx_buf; + const u16 *tx_sbuf; + u8 *tx_dma_buf; + u16 *tx_dma_sbuf; + struct scatterlist *sg; + struct dma_async_tx_descriptor *desc_tx; + struct dma_async_tx_descriptor *desc_rx; + int num; + int i; + int size; + int rem; + int head; + unsigned long flags; + struct pch_spi_dma_ctrl *dma; + + dma = &data->dma; + + /* set baud rate if needed */ + if (data->cur_trans->speed_hz) { + dev_dbg(&data->master->dev, "%s:setting baud rate\n", __func__); + spin_lock_irqsave(&data->lock, flags); + pch_spi_set_baud_rate(data->master, data->cur_trans->speed_hz); + spin_unlock_irqrestore(&data->lock, flags); + } + + /* set bits per word if needed */ + if (data->cur_trans->bits_per_word && + (data->current_msg->spi->bits_per_word != + data->cur_trans->bits_per_word)) { + dev_dbg(&data->master->dev, "%s:set bits per word\n", __func__); + spin_lock_irqsave(&data->lock, flags); + pch_spi_set_bits_per_word(data->master, + data->cur_trans->bits_per_word); + spin_unlock_irqrestore(&data->lock, flags); + *bpw = data->cur_trans->bits_per_word; + } else { + *bpw = data->current_msg->spi->bits_per_word; + } + data->bpw_len = data->cur_trans->len / (*bpw / 8); + + if (data->bpw_len > PCH_BUF_SIZE) { + data->bpw_len = PCH_BUF_SIZE; + data->cur_trans->len -= PCH_BUF_SIZE; + } + + /* copy Tx Data */ + if (data->cur_trans->tx_buf != NULL) { + if (*bpw == 8) { + tx_buf = data->cur_trans->tx_buf; + tx_dma_buf = dma->tx_buf_virt; + for (i = 0; i < data->bpw_len; i++) + *tx_dma_buf++ = *tx_buf++; + } else { + tx_sbuf = data->cur_trans->tx_buf; + tx_dma_sbuf = dma->tx_buf_virt; + for (i = 0; i < data->bpw_len; i++) + *tx_dma_sbuf++ = *tx_sbuf++; + } + } + + /* Calculate Rx parameter for DMA transmitting */ + if (data->bpw_len > PCH_DMA_TRANS_SIZE) { + if (data->bpw_len % PCH_DMA_TRANS_SIZE) { + num = data->bpw_len / PCH_DMA_TRANS_SIZE + 1; + rem = data->bpw_len % PCH_DMA_TRANS_SIZE; + } else { + num = data->bpw_len / PCH_DMA_TRANS_SIZE; + rem = PCH_DMA_TRANS_SIZE; + } + size = PCH_DMA_TRANS_SIZE; + } else { + num = 1; + size = data->bpw_len; + rem = data->bpw_len; + } + dev_dbg(&data->master->dev, "%s num=%d size=%d rem=%d\n", + __func__, num, size, rem); + spin_lock_irqsave(&data->lock, flags); + + /* set receive fifo threshold and transmit fifo threshold */ + pch_spi_setclr_reg(data->master, PCH_SPCR, + ((size - 1) << SPCR_RFIC_FIELD) | + (PCH_TX_THOLD << SPCR_TFIC_FIELD), + MASK_RFIC_SPCR_BITS | MASK_TFIC_SPCR_BITS); + + spin_unlock_irqrestore(&data->lock, flags); + + /* RX */ + dma->sg_rx_p = kzalloc(sizeof(struct scatterlist)*num, GFP_ATOMIC); + sg_init_table(dma->sg_rx_p, num); /* Initialize SG table */ + /* offset, length setting */ + sg = dma->sg_rx_p; + for (i = 0; i < num; i++, sg++) { + if (i == (num - 2)) { + sg->offset = size * i; + sg->offset = sg->offset * (*bpw / 8); + sg_set_page(sg, virt_to_page(dma->rx_buf_virt), rem, + sg->offset); + sg_dma_len(sg) = rem; + } else if (i == (num - 1)) { + sg->offset = size * (i - 1) + rem; + sg->offset = sg->offset * (*bpw / 8); + sg_set_page(sg, virt_to_page(dma->rx_buf_virt), size, + sg->offset); + sg_dma_len(sg) = size; + } else { + sg->offset = size * i; + sg->offset = sg->offset * (*bpw / 8); + sg_set_page(sg, virt_to_page(dma->rx_buf_virt), size, + sg->offset); + sg_dma_len(sg) = size; + } + sg_dma_address(sg) = dma->rx_buf_dma + sg->offset; + } + sg = dma->sg_rx_p; + desc_rx = dmaengine_prep_slave_sg(dma->chan_rx, sg, + num, DMA_DEV_TO_MEM, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + if (!desc_rx) { + dev_err(&data->master->dev, + "%s:dmaengine_prep_slave_sg Failed\n", __func__); + return; + } + dma_sync_sg_for_device(&data->master->dev, sg, num, DMA_FROM_DEVICE); + desc_rx->callback = pch_dma_rx_complete; + desc_rx->callback_param = data; + dma->nent = num; + dma->desc_rx = desc_rx; + + /* Calculate Tx parameter for DMA transmitting */ + if (data->bpw_len > PCH_MAX_FIFO_DEPTH) { + head = PCH_MAX_FIFO_DEPTH - PCH_DMA_TRANS_SIZE; + if (data->bpw_len % PCH_DMA_TRANS_SIZE > 4) { + num = data->bpw_len / PCH_DMA_TRANS_SIZE + 1; + rem = data->bpw_len % PCH_DMA_TRANS_SIZE - head; + } else { + num = data->bpw_len / PCH_DMA_TRANS_SIZE; + rem = data->bpw_len % PCH_DMA_TRANS_SIZE + + PCH_DMA_TRANS_SIZE - head; + } + size = PCH_DMA_TRANS_SIZE; + } else { + num = 1; + size = data->bpw_len; + rem = data->bpw_len; + head = 0; + } + + dma->sg_tx_p = kzalloc(sizeof(struct scatterlist)*num, GFP_ATOMIC); + sg_init_table(dma->sg_tx_p, num); /* Initialize SG table */ + /* offset, length setting */ + sg = dma->sg_tx_p; + for (i = 0; i < num; i++, sg++) { + if (i == 0) { + sg->offset = 0; + sg_set_page(sg, virt_to_page(dma->tx_buf_virt), size + head, + sg->offset); + sg_dma_len(sg) = size + head; + } else if (i == (num - 1)) { + sg->offset = head + size * i; + sg->offset = sg->offset * (*bpw / 8); + sg_set_page(sg, virt_to_page(dma->tx_buf_virt), rem, + sg->offset); + sg_dma_len(sg) = rem; + } else { + sg->offset = head + size * i; + sg->offset = sg->offset * (*bpw / 8); + sg_set_page(sg, virt_to_page(dma->tx_buf_virt), size, + sg->offset); + sg_dma_len(sg) = size; + } + sg_dma_address(sg) = dma->tx_buf_dma + sg->offset; + } + sg = dma->sg_tx_p; + desc_tx = dmaengine_prep_slave_sg(dma->chan_tx, + sg, num, DMA_MEM_TO_DEV, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + if (!desc_tx) { + dev_err(&data->master->dev, + "%s:dmaengine_prep_slave_sg Failed\n", __func__); + return; + } + dma_sync_sg_for_device(&data->master->dev, sg, num, DMA_TO_DEVICE); + desc_tx->callback = NULL; + desc_tx->callback_param = data; + dma->nent = num; + dma->desc_tx = desc_tx; + + dev_dbg(&data->master->dev, "%s:Pulling down SSN low - writing 0x2 to SSNXCR\n", __func__); + + spin_lock_irqsave(&data->lock, flags); + pch_spi_writereg(data->master, PCH_SSNXCR, SSN_LOW); + desc_rx->tx_submit(desc_rx); + desc_tx->tx_submit(desc_tx); + spin_unlock_irqrestore(&data->lock, flags); + + /* reset transfer complete flag */ + data->transfer_complete = false; +} + +static void pch_spi_process_messages(struct work_struct *pwork) +{ + struct spi_message *pmsg, *tmp; + struct pch_spi_data *data; + int bpw; + + data = container_of(pwork, struct pch_spi_data, work); + dev_dbg(&data->master->dev, "%s data initialized\n", __func__); + + spin_lock(&data->lock); + /* check if suspend has been initiated;if yes flush queue */ + if (data->board_dat->suspend_sts || (data->status == STATUS_EXITING)) { + dev_dbg(&data->master->dev, + "%s suspend/remove initiated, flushing queue\n", __func__); + list_for_each_entry_safe(pmsg, tmp, data->queue.next, queue) { + pmsg->status = -EIO; + + if (pmsg->complete) { + spin_unlock(&data->lock); + pmsg->complete(pmsg->context); + spin_lock(&data->lock); + } + + /* delete from queue */ + list_del_init(&pmsg->queue); + } + + spin_unlock(&data->lock); + return; + } + + data->bcurrent_msg_processing = true; + dev_dbg(&data->master->dev, + "%s Set data->bcurrent_msg_processing= true\n", __func__); + + /* Get the message from the queue and delete it from there. */ + data->current_msg = list_entry(data->queue.next, struct spi_message, + queue); + + list_del_init(&data->current_msg->queue); + + data->current_msg->status = 0; + + pch_spi_select_chip(data, data->current_msg->spi); + + spin_unlock(&data->lock); + + if (data->use_dma) + pch_spi_request_dma(data, + data->current_msg->spi->bits_per_word); + pch_spi_writereg(data->master, PCH_SSNXCR, SSN_NO_CONTROL); + do { + int cnt; + /* If we are already processing a message get the next + transfer structure from the message otherwise retrieve + the 1st transfer request from the message. */ + spin_lock(&data->lock); + if (data->cur_trans == NULL) { + data->cur_trans = + list_entry(data->current_msg->transfers.next, + struct spi_transfer, transfer_list); + dev_dbg(&data->master->dev, "%s " + ":Getting 1st transfer message\n", __func__); + } else { + data->cur_trans = + list_entry(data->cur_trans->transfer_list.next, + struct spi_transfer, transfer_list); + dev_dbg(&data->master->dev, "%s " + ":Getting next transfer message\n", __func__); + } + spin_unlock(&data->lock); + + if (!data->cur_trans->len) + goto out; + cnt = (data->cur_trans->len - 1) / PCH_BUF_SIZE + 1; + data->save_total_len = data->cur_trans->len; + if (data->use_dma) { + int i; + char *save_rx_buf = data->cur_trans->rx_buf; + for (i = 0; i < cnt; i ++) { + pch_spi_handle_dma(data, &bpw); + if (!pch_spi_start_transfer(data)) { + data->transfer_complete = true; + data->current_msg->status = -EIO; + data->current_msg->complete + (data->current_msg->context); + data->bcurrent_msg_processing = false; + data->current_msg = NULL; + data->cur_trans = NULL; + goto out; + } + pch_spi_copy_rx_data_for_dma(data, bpw); + } + data->cur_trans->rx_buf = save_rx_buf; + } else { + pch_spi_set_tx(data, &bpw); + pch_spi_set_ir(data); + pch_spi_copy_rx_data(data, bpw); + kfree(data->pkt_rx_buff); + data->pkt_rx_buff = NULL; + kfree(data->pkt_tx_buff); + data->pkt_tx_buff = NULL; + } + /* increment message count */ + data->cur_trans->len = data->save_total_len; + data->current_msg->actual_length += data->cur_trans->len; + + dev_dbg(&data->master->dev, + "%s:data->current_msg->actual_length=%d\n", + __func__, data->current_msg->actual_length); + + /* check for delay */ + if (data->cur_trans->delay_usecs) { + dev_dbg(&data->master->dev, "%s:" + "delay in usec=%d\n", __func__, + data->cur_trans->delay_usecs); + udelay(data->cur_trans->delay_usecs); + } + + spin_lock(&data->lock); + + /* No more transfer in this message. */ + if ((data->cur_trans->transfer_list.next) == + &(data->current_msg->transfers)) { + pch_spi_nomore_transfer(data); + } + + spin_unlock(&data->lock); + + } while (data->cur_trans != NULL); + +out: + pch_spi_writereg(data->master, PCH_SSNXCR, SSN_HIGH); + if (data->use_dma) + pch_spi_release_dma(data); +} + +static void pch_spi_free_resources(struct pch_spi_board_data *board_dat, + struct pch_spi_data *data) +{ + dev_dbg(&board_dat->pdev->dev, "%s ENTRY\n", __func__); + + /* free workqueue */ + if (data->wk != NULL) { + destroy_workqueue(data->wk); + data->wk = NULL; + dev_dbg(&board_dat->pdev->dev, + "%s destroy_workqueue invoked successfully\n", + __func__); + } +} + +static int pch_spi_get_resources(struct pch_spi_board_data *board_dat, + struct pch_spi_data *data) +{ + int retval = 0; + + dev_dbg(&board_dat->pdev->dev, "%s ENTRY\n", __func__); + + /* create workqueue */ + data->wk = create_singlethread_workqueue(KBUILD_MODNAME); + if (!data->wk) { + dev_err(&board_dat->pdev->dev, + "%s create_singlet hread_workqueue failed\n", __func__); + retval = -EBUSY; + goto err_return; + } + + /* reset PCH SPI h/w */ + pch_spi_reset(data->master); + dev_dbg(&board_dat->pdev->dev, + "%s pch_spi_reset invoked successfully\n", __func__); + + dev_dbg(&board_dat->pdev->dev, "%s data->irq_reg_sts=true\n", __func__); + +err_return: + if (retval != 0) { + dev_err(&board_dat->pdev->dev, + "%s FAIL:invoking pch_spi_free_resources\n", __func__); + pch_spi_free_resources(board_dat, data); + } + + dev_dbg(&board_dat->pdev->dev, "%s Return=%d\n", __func__, retval); + + return retval; +} + +static void pch_free_dma_buf(struct pch_spi_board_data *board_dat, + struct pch_spi_data *data) +{ + struct pch_spi_dma_ctrl *dma; + + dma = &data->dma; + if (dma->tx_buf_dma) + dma_free_coherent(&board_dat->pdev->dev, PCH_BUF_SIZE, + dma->tx_buf_virt, dma->tx_buf_dma); + if (dma->rx_buf_dma) + dma_free_coherent(&board_dat->pdev->dev, PCH_BUF_SIZE, + dma->rx_buf_virt, dma->rx_buf_dma); + return; +} + +static void pch_alloc_dma_buf(struct pch_spi_board_data *board_dat, + struct pch_spi_data *data) +{ + struct pch_spi_dma_ctrl *dma; + + dma = &data->dma; + /* Get Consistent memory for Tx DMA */ + dma->tx_buf_virt = dma_alloc_coherent(&board_dat->pdev->dev, + PCH_BUF_SIZE, &dma->tx_buf_dma, GFP_KERNEL); + /* Get Consistent memory for Rx DMA */ + dma->rx_buf_virt = dma_alloc_coherent(&board_dat->pdev->dev, + PCH_BUF_SIZE, &dma->rx_buf_dma, GFP_KERNEL); +} + +static int pch_spi_pd_probe(struct platform_device *plat_dev) +{ + int ret; + struct spi_master *master; + struct pch_spi_board_data *board_dat = dev_get_platdata(&plat_dev->dev); + struct pch_spi_data *data; + + dev_dbg(&plat_dev->dev, "%s:debug\n", __func__); + + master = spi_alloc_master(&board_dat->pdev->dev, + sizeof(struct pch_spi_data)); + if (!master) { + dev_err(&plat_dev->dev, "spi_alloc_master[%d] failed.\n", + plat_dev->id); + return -ENOMEM; + } + + data = spi_master_get_devdata(master); + data->master = master; + + platform_set_drvdata(plat_dev, data); + + /* baseaddress + address offset) */ + data->io_base_addr = pci_resource_start(board_dat->pdev, 1) + + PCH_ADDRESS_SIZE * plat_dev->id; + data->io_remap_addr = pci_iomap(board_dat->pdev, 1, 0); + if (!data->io_remap_addr) { + dev_err(&plat_dev->dev, "%s pci_iomap failed\n", __func__); + ret = -ENOMEM; + goto err_pci_iomap; + } + data->io_remap_addr += PCH_ADDRESS_SIZE * plat_dev->id; + + dev_dbg(&plat_dev->dev, "[ch%d] remap_addr=%p\n", + plat_dev->id, data->io_remap_addr); + + /* initialize members of SPI master */ + master->num_chipselect = PCH_MAX_CS; + master->transfer = pch_spi_transfer; + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST; + master->bits_per_word_mask = SPI_BPW_MASK(8) | SPI_BPW_MASK(16); + master->max_speed_hz = PCH_MAX_BAUDRATE; + + data->board_dat = board_dat; + data->plat_dev = plat_dev; + data->n_curnt_chip = 255; + data->status = STATUS_RUNNING; + data->ch = plat_dev->id; + data->use_dma = use_dma; + + INIT_LIST_HEAD(&data->queue); + spin_lock_init(&data->lock); + INIT_WORK(&data->work, pch_spi_process_messages); + init_waitqueue_head(&data->wait); + + ret = pch_spi_get_resources(board_dat, data); + if (ret) { + dev_err(&plat_dev->dev, "%s fail(retval=%d)\n", __func__, ret); + goto err_spi_get_resources; + } + + ret = request_irq(board_dat->pdev->irq, pch_spi_handler, + IRQF_SHARED, KBUILD_MODNAME, data); + if (ret) { + dev_err(&plat_dev->dev, + "%s request_irq failed\n", __func__); + goto err_request_irq; + } + data->irq_reg_sts = true; + + pch_spi_set_master_mode(master); + + if (use_dma) { + dev_info(&plat_dev->dev, "Use DMA for data transfers\n"); + pch_alloc_dma_buf(board_dat, data); + } + + ret = spi_register_master(master); + if (ret != 0) { + dev_err(&plat_dev->dev, + "%s spi_register_master FAILED\n", __func__); + goto err_spi_register_master; + } + + return 0; + +err_spi_register_master: + pch_free_dma_buf(board_dat, data); + free_irq(board_dat->pdev->irq, data); +err_request_irq: + pch_spi_free_resources(board_dat, data); +err_spi_get_resources: + pci_iounmap(board_dat->pdev, data->io_remap_addr); +err_pci_iomap: + spi_master_put(master); + + return ret; +} + +static int pch_spi_pd_remove(struct platform_device *plat_dev) +{ + struct pch_spi_board_data *board_dat = dev_get_platdata(&plat_dev->dev); + struct pch_spi_data *data = platform_get_drvdata(plat_dev); + int count; + unsigned long flags; + + dev_dbg(&plat_dev->dev, "%s:[ch%d] irq=%d\n", + __func__, plat_dev->id, board_dat->pdev->irq); + + if (use_dma) + pch_free_dma_buf(board_dat, data); + + /* check for any pending messages; no action is taken if the queue + * is still full; but at least we tried. Unload anyway */ + count = 500; + spin_lock_irqsave(&data->lock, flags); + data->status = STATUS_EXITING; + while ((list_empty(&data->queue) == 0) && --count) { + dev_dbg(&board_dat->pdev->dev, "%s :queue not empty\n", + __func__); + spin_unlock_irqrestore(&data->lock, flags); + msleep(PCH_SLEEP_TIME); + spin_lock_irqsave(&data->lock, flags); + } + spin_unlock_irqrestore(&data->lock, flags); + + pch_spi_free_resources(board_dat, data); + /* disable interrupts & free IRQ */ + if (data->irq_reg_sts) { + /* disable interrupts */ + pch_spi_setclr_reg(data->master, PCH_SPCR, 0, PCH_ALL); + data->irq_reg_sts = false; + free_irq(board_dat->pdev->irq, data); + } + + pci_iounmap(board_dat->pdev, data->io_remap_addr); + spi_unregister_master(data->master); + + return 0; +} +#ifdef CONFIG_PM +static int pch_spi_pd_suspend(struct platform_device *pd_dev, + pm_message_t state) +{ + u8 count; + struct pch_spi_board_data *board_dat = dev_get_platdata(&pd_dev->dev); + struct pch_spi_data *data = platform_get_drvdata(pd_dev); + + dev_dbg(&pd_dev->dev, "%s ENTRY\n", __func__); + + if (!board_dat) { + dev_err(&pd_dev->dev, + "%s pci_get_drvdata returned NULL\n", __func__); + return -EFAULT; + } + + /* check if the current message is processed: + Only after thats done the transfer will be suspended */ + count = 255; + while ((--count) > 0) { + if (!(data->bcurrent_msg_processing)) + break; + msleep(PCH_SLEEP_TIME); + } + + /* Free IRQ */ + if (data->irq_reg_sts) { + /* disable all interrupts */ + pch_spi_setclr_reg(data->master, PCH_SPCR, 0, PCH_ALL); + pch_spi_reset(data->master); + free_irq(board_dat->pdev->irq, data); + + data->irq_reg_sts = false; + dev_dbg(&pd_dev->dev, + "%s free_irq invoked successfully.\n", __func__); + } + + return 0; +} + +static int pch_spi_pd_resume(struct platform_device *pd_dev) +{ + struct pch_spi_board_data *board_dat = dev_get_platdata(&pd_dev->dev); + struct pch_spi_data *data = platform_get_drvdata(pd_dev); + int retval; + + if (!board_dat) { + dev_err(&pd_dev->dev, + "%s pci_get_drvdata returned NULL\n", __func__); + return -EFAULT; + } + + if (!data->irq_reg_sts) { + /* register IRQ */ + retval = request_irq(board_dat->pdev->irq, pch_spi_handler, + IRQF_SHARED, KBUILD_MODNAME, data); + if (retval < 0) { + dev_err(&pd_dev->dev, + "%s request_irq failed\n", __func__); + return retval; + } + + /* reset PCH SPI h/w */ + pch_spi_reset(data->master); + pch_spi_set_master_mode(data->master); + data->irq_reg_sts = true; + } + return 0; +} +#else +#define pch_spi_pd_suspend NULL +#define pch_spi_pd_resume NULL +#endif + +static struct platform_driver pch_spi_pd_driver = { + .driver = { + .name = "pch-spi", + }, + .probe = pch_spi_pd_probe, + .remove = pch_spi_pd_remove, + .suspend = pch_spi_pd_suspend, + .resume = pch_spi_pd_resume +}; + +static int pch_spi_probe(struct pci_dev *pdev, const struct pci_device_id *id) +{ + struct pch_spi_board_data *board_dat; + struct platform_device *pd_dev = NULL; + int retval; + int i; + struct pch_pd_dev_save *pd_dev_save; + + pd_dev_save = kzalloc(sizeof(struct pch_pd_dev_save), GFP_KERNEL); + if (!pd_dev_save) + return -ENOMEM; + + board_dat = kzalloc(sizeof(struct pch_spi_board_data), GFP_KERNEL); + if (!board_dat) { + retval = -ENOMEM; + goto err_no_mem; + } + + retval = pci_request_regions(pdev, KBUILD_MODNAME); + if (retval) { + dev_err(&pdev->dev, "%s request_region failed\n", __func__); + goto pci_request_regions; + } + + board_dat->pdev = pdev; + board_dat->num = id->driver_data; + pd_dev_save->num = id->driver_data; + pd_dev_save->board_dat = board_dat; + + retval = pci_enable_device(pdev); + if (retval) { + dev_err(&pdev->dev, "%s pci_enable_device failed\n", __func__); + goto pci_enable_device; + } + + for (i = 0; i < board_dat->num; i++) { + pd_dev = platform_device_alloc("pch-spi", i); + if (!pd_dev) { + dev_err(&pdev->dev, "platform_device_alloc failed\n"); + retval = -ENOMEM; + goto err_platform_device; + } + pd_dev_save->pd_save[i] = pd_dev; + pd_dev->dev.parent = &pdev->dev; + + retval = platform_device_add_data(pd_dev, board_dat, + sizeof(*board_dat)); + if (retval) { + dev_err(&pdev->dev, + "platform_device_add_data failed\n"); + platform_device_put(pd_dev); + goto err_platform_device; + } + + retval = platform_device_add(pd_dev); + if (retval) { + dev_err(&pdev->dev, "platform_device_add failed\n"); + platform_device_put(pd_dev); + goto err_platform_device; + } + } + + pci_set_drvdata(pdev, pd_dev_save); + + return 0; + +err_platform_device: + while (--i >= 0) + platform_device_unregister(pd_dev_save->pd_save[i]); + pci_disable_device(pdev); +pci_enable_device: + pci_release_regions(pdev); +pci_request_regions: + kfree(board_dat); +err_no_mem: + kfree(pd_dev_save); + + return retval; +} + +static void pch_spi_remove(struct pci_dev *pdev) +{ + int i; + struct pch_pd_dev_save *pd_dev_save = pci_get_drvdata(pdev); + + dev_dbg(&pdev->dev, "%s ENTRY:pdev=%p\n", __func__, pdev); + + for (i = 0; i < pd_dev_save->num; i++) + platform_device_unregister(pd_dev_save->pd_save[i]); + + pci_disable_device(pdev); + pci_release_regions(pdev); + kfree(pd_dev_save->board_dat); + kfree(pd_dev_save); +} + +#ifdef CONFIG_PM +static int pch_spi_suspend(struct pci_dev *pdev, pm_message_t state) +{ + int retval; + struct pch_pd_dev_save *pd_dev_save = pci_get_drvdata(pdev); + + dev_dbg(&pdev->dev, "%s ENTRY\n", __func__); + + pd_dev_save->board_dat->suspend_sts = true; + + /* save config space */ + retval = pci_save_state(pdev); + if (retval == 0) { + pci_enable_wake(pdev, PCI_D3hot, 0); + pci_disable_device(pdev); + pci_set_power_state(pdev, PCI_D3hot); + } else { + dev_err(&pdev->dev, "%s pci_save_state failed\n", __func__); + } + + return retval; +} + +static int pch_spi_resume(struct pci_dev *pdev) +{ + int retval; + struct pch_pd_dev_save *pd_dev_save = pci_get_drvdata(pdev); + dev_dbg(&pdev->dev, "%s ENTRY\n", __func__); + + pci_set_power_state(pdev, PCI_D0); + pci_restore_state(pdev); + + retval = pci_enable_device(pdev); + if (retval < 0) { + dev_err(&pdev->dev, + "%s pci_enable_device failed\n", __func__); + } else { + pci_enable_wake(pdev, PCI_D3hot, 0); + + /* set suspend status to false */ + pd_dev_save->board_dat->suspend_sts = false; + } + + return retval; +} +#else +#define pch_spi_suspend NULL +#define pch_spi_resume NULL + +#endif + +static struct pci_driver pch_spi_pcidev_driver = { + .name = "pch_spi", + .id_table = pch_spi_pcidev_id, + .probe = pch_spi_probe, + .remove = pch_spi_remove, + .suspend = pch_spi_suspend, + .resume = pch_spi_resume, +}; + +static int __init pch_spi_init(void) +{ + int ret; + ret = platform_driver_register(&pch_spi_pd_driver); + if (ret) + return ret; + + ret = pci_register_driver(&pch_spi_pcidev_driver); + if (ret) { + platform_driver_unregister(&pch_spi_pd_driver); + return ret; + } + + return 0; +} +module_init(pch_spi_init); + +static void __exit pch_spi_exit(void) +{ + pci_unregister_driver(&pch_spi_pcidev_driver); + platform_driver_unregister(&pch_spi_pd_driver); +} +module_exit(pch_spi_exit); + +module_param(use_dma, int, 0644); +MODULE_PARM_DESC(use_dma, + "to use DMA for data transfers pass 1 else 0; default 1"); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("Intel EG20T PCH/LAPIS Semiconductor ML7xxx IOH SPI Driver"); +MODULE_DEVICE_TABLE(pci, pch_spi_pcidev_id); + diff --git a/drivers/spi/spi-txx9.c b/drivers/spi/spi-txx9.c new file mode 100644 index 000000000..9190124b6 --- /dev/null +++ b/drivers/spi/spi-txx9.c @@ -0,0 +1,444 @@ +/* + * TXx9 SPI controller driver. + * + * Based on linux/arch/mips/tx4938/toshiba_rbtx4938/spi_txx9.c + * Copyright (C) 2000-2001 Toshiba Corporation + * + * 2003-2005 (c) MontaVista Software, Inc. This file is licensed under the + * terms of the GNU General Public License version 2. This program is + * licensed "as is" without any warranty of any kind, whether express + * or implied. + * + * Support for TX4938 in 2.6 - Manish Lachwani (mlachwani@mvista.com) + * + * Convert to generic SPI framework - Atsushi Nemoto (anemo@mba.ocn.ne.jp) + */ +#include <linux/init.h> +#include <linux/delay.h> +#include <linux/errno.h> +#include <linux/interrupt.h> +#include <linux/platform_device.h> +#include <linux/sched.h> +#include <linux/spinlock.h> +#include <linux/workqueue.h> +#include <linux/spi/spi.h> +#include <linux/err.h> +#include <linux/clk.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/gpio.h> + + +#define SPI_FIFO_SIZE 4 +#define SPI_MAX_DIVIDER 0xff /* Max. value for SPCR1.SER */ +#define SPI_MIN_DIVIDER 1 /* Min. value for SPCR1.SER */ + +#define TXx9_SPMCR 0x00 +#define TXx9_SPCR0 0x04 +#define TXx9_SPCR1 0x08 +#define TXx9_SPFS 0x0c +#define TXx9_SPSR 0x14 +#define TXx9_SPDR 0x18 + +/* SPMCR : SPI Master Control */ +#define TXx9_SPMCR_OPMODE 0xc0 +#define TXx9_SPMCR_CONFIG 0x40 +#define TXx9_SPMCR_ACTIVE 0x80 +#define TXx9_SPMCR_SPSTP 0x02 +#define TXx9_SPMCR_BCLR 0x01 + +/* SPCR0 : SPI Control 0 */ +#define TXx9_SPCR0_TXIFL_MASK 0xc000 +#define TXx9_SPCR0_RXIFL_MASK 0x3000 +#define TXx9_SPCR0_SIDIE 0x0800 +#define TXx9_SPCR0_SOEIE 0x0400 +#define TXx9_SPCR0_RBSIE 0x0200 +#define TXx9_SPCR0_TBSIE 0x0100 +#define TXx9_SPCR0_IFSPSE 0x0010 +#define TXx9_SPCR0_SBOS 0x0004 +#define TXx9_SPCR0_SPHA 0x0002 +#define TXx9_SPCR0_SPOL 0x0001 + +/* SPSR : SPI Status */ +#define TXx9_SPSR_TBSI 0x8000 +#define TXx9_SPSR_RBSI 0x4000 +#define TXx9_SPSR_TBS_MASK 0x3800 +#define TXx9_SPSR_RBS_MASK 0x0700 +#define TXx9_SPSR_SPOE 0x0080 +#define TXx9_SPSR_IFSD 0x0008 +#define TXx9_SPSR_SIDLE 0x0004 +#define TXx9_SPSR_STRDY 0x0002 +#define TXx9_SPSR_SRRDY 0x0001 + + +struct txx9spi { + struct workqueue_struct *workqueue; + struct work_struct work; + spinlock_t lock; /* protect 'queue' */ + struct list_head queue; + wait_queue_head_t waitq; + void __iomem *membase; + int baseclk; + struct clk *clk; + int last_chipselect; + int last_chipselect_val; +}; + +static u32 txx9spi_rd(struct txx9spi *c, int reg) +{ + return __raw_readl(c->membase + reg); +} +static void txx9spi_wr(struct txx9spi *c, u32 val, int reg) +{ + __raw_writel(val, c->membase + reg); +} + +static void txx9spi_cs_func(struct spi_device *spi, struct txx9spi *c, + int on, unsigned int cs_delay) +{ + int val = (spi->mode & SPI_CS_HIGH) ? on : !on; + + if (on) { + /* deselect the chip with cs_change hint in last transfer */ + if (c->last_chipselect >= 0) + gpio_set_value(c->last_chipselect, + !c->last_chipselect_val); + c->last_chipselect = spi->chip_select; + c->last_chipselect_val = val; + } else { + c->last_chipselect = -1; + ndelay(cs_delay); /* CS Hold Time */ + } + gpio_set_value(spi->chip_select, val); + ndelay(cs_delay); /* CS Setup Time / CS Recovery Time */ +} + +static int txx9spi_setup(struct spi_device *spi) +{ + struct txx9spi *c = spi_master_get_devdata(spi->master); + + if (!spi->max_speed_hz) + return -EINVAL; + + if (gpio_direction_output(spi->chip_select, + !(spi->mode & SPI_CS_HIGH))) { + dev_err(&spi->dev, "Cannot setup GPIO for chipselect.\n"); + return -EINVAL; + } + + /* deselect chip */ + spin_lock(&c->lock); + txx9spi_cs_func(spi, c, 0, (NSEC_PER_SEC / 2) / spi->max_speed_hz); + spin_unlock(&c->lock); + + return 0; +} + +static irqreturn_t txx9spi_interrupt(int irq, void *dev_id) +{ + struct txx9spi *c = dev_id; + + /* disable rx intr */ + txx9spi_wr(c, txx9spi_rd(c, TXx9_SPCR0) & ~TXx9_SPCR0_RBSIE, + TXx9_SPCR0); + wake_up(&c->waitq); + return IRQ_HANDLED; +} + +static void txx9spi_work_one(struct txx9spi *c, struct spi_message *m) +{ + struct spi_device *spi = m->spi; + struct spi_transfer *t; + unsigned int cs_delay; + unsigned int cs_change = 1; + int status = 0; + u32 mcr; + u32 prev_speed_hz = 0; + u8 prev_bits_per_word = 0; + + /* CS setup/hold/recovery time in nsec */ + cs_delay = 100 + (NSEC_PER_SEC / 2) / spi->max_speed_hz; + + mcr = txx9spi_rd(c, TXx9_SPMCR); + if (unlikely((mcr & TXx9_SPMCR_OPMODE) == TXx9_SPMCR_ACTIVE)) { + dev_err(&spi->dev, "Bad mode.\n"); + status = -EIO; + goto exit; + } + mcr &= ~(TXx9_SPMCR_OPMODE | TXx9_SPMCR_SPSTP | TXx9_SPMCR_BCLR); + + /* enter config mode */ + txx9spi_wr(c, mcr | TXx9_SPMCR_CONFIG | TXx9_SPMCR_BCLR, TXx9_SPMCR); + txx9spi_wr(c, TXx9_SPCR0_SBOS + | ((spi->mode & SPI_CPOL) ? TXx9_SPCR0_SPOL : 0) + | ((spi->mode & SPI_CPHA) ? TXx9_SPCR0_SPHA : 0) + | 0x08, + TXx9_SPCR0); + + list_for_each_entry(t, &m->transfers, transfer_list) { + const void *txbuf = t->tx_buf; + void *rxbuf = t->rx_buf; + u32 data; + unsigned int len = t->len; + unsigned int wsize; + u32 speed_hz = t->speed_hz ? : spi->max_speed_hz; + u8 bits_per_word = t->bits_per_word; + + wsize = bits_per_word >> 3; /* in bytes */ + + if (prev_speed_hz != speed_hz + || prev_bits_per_word != bits_per_word) { + int n = DIV_ROUND_UP(c->baseclk, speed_hz) - 1; + + n = clamp(n, SPI_MIN_DIVIDER, SPI_MAX_DIVIDER); + /* enter config mode */ + txx9spi_wr(c, mcr | TXx9_SPMCR_CONFIG | TXx9_SPMCR_BCLR, + TXx9_SPMCR); + txx9spi_wr(c, (n << 8) | bits_per_word, TXx9_SPCR1); + /* enter active mode */ + txx9spi_wr(c, mcr | TXx9_SPMCR_ACTIVE, TXx9_SPMCR); + + prev_speed_hz = speed_hz; + prev_bits_per_word = bits_per_word; + } + + if (cs_change) + txx9spi_cs_func(spi, c, 1, cs_delay); + cs_change = t->cs_change; + while (len) { + unsigned int count = SPI_FIFO_SIZE; + int i; + u32 cr0; + + if (len < count * wsize) + count = len / wsize; + /* now tx must be idle... */ + while (!(txx9spi_rd(c, TXx9_SPSR) & TXx9_SPSR_SIDLE)) + cpu_relax(); + cr0 = txx9spi_rd(c, TXx9_SPCR0); + cr0 &= ~TXx9_SPCR0_RXIFL_MASK; + cr0 |= (count - 1) << 12; + /* enable rx intr */ + cr0 |= TXx9_SPCR0_RBSIE; + txx9spi_wr(c, cr0, TXx9_SPCR0); + /* send */ + for (i = 0; i < count; i++) { + if (txbuf) { + data = (wsize == 1) + ? *(const u8 *)txbuf + : *(const u16 *)txbuf; + txx9spi_wr(c, data, TXx9_SPDR); + txbuf += wsize; + } else + txx9spi_wr(c, 0, TXx9_SPDR); + } + /* wait all rx data */ + wait_event(c->waitq, + txx9spi_rd(c, TXx9_SPSR) & TXx9_SPSR_RBSI); + /* receive */ + for (i = 0; i < count; i++) { + data = txx9spi_rd(c, TXx9_SPDR); + if (rxbuf) { + if (wsize == 1) + *(u8 *)rxbuf = data; + else + *(u16 *)rxbuf = data; + rxbuf += wsize; + } + } + len -= count * wsize; + } + m->actual_length += t->len; + if (t->delay_usecs) + udelay(t->delay_usecs); + + if (!cs_change) + continue; + if (t->transfer_list.next == &m->transfers) + break; + /* sometimes a short mid-message deselect of the chip + * may be needed to terminate a mode or command + */ + txx9spi_cs_func(spi, c, 0, cs_delay); + } + +exit: + m->status = status; + if (m->complete) + m->complete(m->context); + + /* normally deactivate chipselect ... unless no error and + * cs_change has hinted that the next message will probably + * be for this chip too. + */ + if (!(status == 0 && cs_change)) + txx9spi_cs_func(spi, c, 0, cs_delay); + + /* enter config mode */ + txx9spi_wr(c, mcr | TXx9_SPMCR_CONFIG | TXx9_SPMCR_BCLR, TXx9_SPMCR); +} + +static void txx9spi_work(struct work_struct *work) +{ + struct txx9spi *c = container_of(work, struct txx9spi, work); + unsigned long flags; + + spin_lock_irqsave(&c->lock, flags); + while (!list_empty(&c->queue)) { + struct spi_message *m; + + m = container_of(c->queue.next, struct spi_message, queue); + list_del_init(&m->queue); + spin_unlock_irqrestore(&c->lock, flags); + + txx9spi_work_one(c, m); + + spin_lock_irqsave(&c->lock, flags); + } + spin_unlock_irqrestore(&c->lock, flags); +} + +static int txx9spi_transfer(struct spi_device *spi, struct spi_message *m) +{ + struct spi_master *master = spi->master; + struct txx9spi *c = spi_master_get_devdata(master); + struct spi_transfer *t; + unsigned long flags; + + m->actual_length = 0; + + /* check each transfer's parameters */ + list_for_each_entry(t, &m->transfers, transfer_list) { + if (!t->tx_buf && !t->rx_buf && t->len) + return -EINVAL; + } + + spin_lock_irqsave(&c->lock, flags); + list_add_tail(&m->queue, &c->queue); + queue_work(c->workqueue, &c->work); + spin_unlock_irqrestore(&c->lock, flags); + + return 0; +} + +static int txx9spi_probe(struct platform_device *dev) +{ + struct spi_master *master; + struct txx9spi *c; + struct resource *res; + int ret = -ENODEV; + u32 mcr; + int irq; + + master = spi_alloc_master(&dev->dev, sizeof(*c)); + if (!master) + return ret; + c = spi_master_get_devdata(master); + platform_set_drvdata(dev, master); + + INIT_WORK(&c->work, txx9spi_work); + spin_lock_init(&c->lock); + INIT_LIST_HEAD(&c->queue); + init_waitqueue_head(&c->waitq); + + c->clk = devm_clk_get(&dev->dev, "spi-baseclk"); + if (IS_ERR(c->clk)) { + ret = PTR_ERR(c->clk); + c->clk = NULL; + goto exit; + } + ret = clk_enable(c->clk); + if (ret) { + c->clk = NULL; + goto exit; + } + c->baseclk = clk_get_rate(c->clk); + master->min_speed_hz = DIV_ROUND_UP(c->baseclk, SPI_MAX_DIVIDER + 1); + master->max_speed_hz = c->baseclk / (SPI_MIN_DIVIDER + 1); + + res = platform_get_resource(dev, IORESOURCE_MEM, 0); + c->membase = devm_ioremap_resource(&dev->dev, res); + if (IS_ERR(c->membase)) + goto exit_busy; + + /* enter config mode */ + mcr = txx9spi_rd(c, TXx9_SPMCR); + mcr &= ~(TXx9_SPMCR_OPMODE | TXx9_SPMCR_SPSTP | TXx9_SPMCR_BCLR); + txx9spi_wr(c, mcr | TXx9_SPMCR_CONFIG | TXx9_SPMCR_BCLR, TXx9_SPMCR); + + irq = platform_get_irq(dev, 0); + if (irq < 0) + goto exit_busy; + ret = devm_request_irq(&dev->dev, irq, txx9spi_interrupt, 0, + "spi_txx9", c); + if (ret) + goto exit; + + c->workqueue = create_singlethread_workqueue( + dev_name(master->dev.parent)); + if (!c->workqueue) + goto exit_busy; + c->last_chipselect = -1; + + dev_info(&dev->dev, "at %#llx, irq %d, %dMHz\n", + (unsigned long long)res->start, irq, + (c->baseclk + 500000) / 1000000); + + /* the spi->mode bits understood by this driver: */ + master->mode_bits = SPI_CS_HIGH | SPI_CPOL | SPI_CPHA; + + master->bus_num = dev->id; + master->setup = txx9spi_setup; + master->transfer = txx9spi_transfer; + master->num_chipselect = (u16)UINT_MAX; /* any GPIO numbers */ + master->bits_per_word_mask = SPI_BPW_MASK(8) | SPI_BPW_MASK(16); + + ret = devm_spi_register_master(&dev->dev, master); + if (ret) + goto exit; + return 0; +exit_busy: + ret = -EBUSY; +exit: + if (c->workqueue) + destroy_workqueue(c->workqueue); + clk_disable(c->clk); + spi_master_put(master); + return ret; +} + +static int txx9spi_remove(struct platform_device *dev) +{ + struct spi_master *master = platform_get_drvdata(dev); + struct txx9spi *c = spi_master_get_devdata(master); + + destroy_workqueue(c->workqueue); + clk_disable(c->clk); + return 0; +} + +/* work with hotplug and coldplug */ +MODULE_ALIAS("platform:spi_txx9"); + +static struct platform_driver txx9spi_driver = { + .probe = txx9spi_probe, + .remove = txx9spi_remove, + .driver = { + .name = "spi_txx9", + }, +}; + +static int __init txx9spi_init(void) +{ + return platform_driver_register(&txx9spi_driver); +} +subsys_initcall(txx9spi_init); + +static void __exit txx9spi_exit(void) +{ + platform_driver_unregister(&txx9spi_driver); +} +module_exit(txx9spi_exit); + +MODULE_DESCRIPTION("TXx9 SPI Driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/spi/spi-xcomm.c b/drivers/spi/spi-xcomm.c new file mode 100644 index 000000000..bb478dccf --- /dev/null +++ b/drivers/spi/spi-xcomm.c @@ -0,0 +1,253 @@ +/* + * Analog Devices AD-FMCOMMS1-EBZ board I2C-SPI bridge driver + * + * Copyright 2012 Analog Devices Inc. + * Author: Lars-Peter Clausen <lars@metafoo.de> + * + * Licensed under the GPL-2 or later. + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/delay.h> +#include <linux/i2c.h> +#include <linux/spi/spi.h> +#include <asm/unaligned.h> + +#define SPI_XCOMM_SETTINGS_LEN_OFFSET 10 +#define SPI_XCOMM_SETTINGS_3WIRE BIT(6) +#define SPI_XCOMM_SETTINGS_CS_HIGH BIT(5) +#define SPI_XCOMM_SETTINGS_SAMPLE_END BIT(4) +#define SPI_XCOMM_SETTINGS_CPHA BIT(3) +#define SPI_XCOMM_SETTINGS_CPOL BIT(2) +#define SPI_XCOMM_SETTINGS_CLOCK_DIV_MASK 0x3 +#define SPI_XCOMM_SETTINGS_CLOCK_DIV_64 0x2 +#define SPI_XCOMM_SETTINGS_CLOCK_DIV_16 0x1 +#define SPI_XCOMM_SETTINGS_CLOCK_DIV_4 0x0 + +#define SPI_XCOMM_CMD_UPDATE_CONFIG 0x03 +#define SPI_XCOMM_CMD_WRITE 0x04 + +#define SPI_XCOMM_CLOCK 48000000 + +struct spi_xcomm { + struct i2c_client *i2c; + + uint16_t settings; + uint16_t chipselect; + + unsigned int current_speed; + + uint8_t buf[63]; +}; + +static int spi_xcomm_sync_config(struct spi_xcomm *spi_xcomm, unsigned int len) +{ + uint16_t settings; + uint8_t *buf = spi_xcomm->buf; + + settings = spi_xcomm->settings; + settings |= len << SPI_XCOMM_SETTINGS_LEN_OFFSET; + + buf[0] = SPI_XCOMM_CMD_UPDATE_CONFIG; + put_unaligned_be16(settings, &buf[1]); + put_unaligned_be16(spi_xcomm->chipselect, &buf[3]); + + return i2c_master_send(spi_xcomm->i2c, buf, 5); +} + +static void spi_xcomm_chipselect(struct spi_xcomm *spi_xcomm, + struct spi_device *spi, int is_active) +{ + unsigned long cs = spi->chip_select; + uint16_t chipselect = spi_xcomm->chipselect; + + if (is_active) + chipselect |= BIT(cs); + else + chipselect &= ~BIT(cs); + + spi_xcomm->chipselect = chipselect; +} + +static int spi_xcomm_setup_transfer(struct spi_xcomm *spi_xcomm, + struct spi_device *spi, struct spi_transfer *t, unsigned int *settings) +{ + if (t->len > 62) + return -EINVAL; + + if (t->speed_hz != spi_xcomm->current_speed) { + unsigned int divider; + + divider = DIV_ROUND_UP(SPI_XCOMM_CLOCK, t->speed_hz); + if (divider >= 64) + *settings |= SPI_XCOMM_SETTINGS_CLOCK_DIV_64; + else if (divider >= 16) + *settings |= SPI_XCOMM_SETTINGS_CLOCK_DIV_16; + else + *settings |= SPI_XCOMM_SETTINGS_CLOCK_DIV_4; + + spi_xcomm->current_speed = t->speed_hz; + } + + if (spi->mode & SPI_CPOL) + *settings |= SPI_XCOMM_SETTINGS_CPOL; + else + *settings &= ~SPI_XCOMM_SETTINGS_CPOL; + + if (spi->mode & SPI_CPHA) + *settings &= ~SPI_XCOMM_SETTINGS_CPHA; + else + *settings |= SPI_XCOMM_SETTINGS_CPHA; + + if (spi->mode & SPI_3WIRE) + *settings |= SPI_XCOMM_SETTINGS_3WIRE; + else + *settings &= ~SPI_XCOMM_SETTINGS_3WIRE; + + return 0; +} + +static int spi_xcomm_txrx_bufs(struct spi_xcomm *spi_xcomm, + struct spi_device *spi, struct spi_transfer *t) +{ + int ret; + + if (t->tx_buf) { + spi_xcomm->buf[0] = SPI_XCOMM_CMD_WRITE; + memcpy(spi_xcomm->buf + 1, t->tx_buf, t->len); + + ret = i2c_master_send(spi_xcomm->i2c, spi_xcomm->buf, t->len + 1); + if (ret < 0) + return ret; + else if (ret != t->len + 1) + return -EIO; + } else if (t->rx_buf) { + ret = i2c_master_recv(spi_xcomm->i2c, t->rx_buf, t->len); + if (ret < 0) + return ret; + else if (ret != t->len) + return -EIO; + } + + return t->len; +} + +static int spi_xcomm_transfer_one(struct spi_master *master, + struct spi_message *msg) +{ + struct spi_xcomm *spi_xcomm = spi_master_get_devdata(master); + unsigned int settings = spi_xcomm->settings; + struct spi_device *spi = msg->spi; + unsigned cs_change = 0; + struct spi_transfer *t; + bool is_first = true; + int status = 0; + bool is_last; + + spi_xcomm_chipselect(spi_xcomm, spi, true); + + list_for_each_entry(t, &msg->transfers, transfer_list) { + + if (!t->tx_buf && !t->rx_buf && t->len) { + status = -EINVAL; + break; + } + + status = spi_xcomm_setup_transfer(spi_xcomm, spi, t, &settings); + if (status < 0) + break; + + is_last = list_is_last(&t->transfer_list, &msg->transfers); + cs_change = t->cs_change; + + if (cs_change ^ is_last) + settings |= BIT(5); + else + settings &= ~BIT(5); + + if (t->rx_buf) { + spi_xcomm->settings = settings; + status = spi_xcomm_sync_config(spi_xcomm, t->len); + if (status < 0) + break; + } else if (settings != spi_xcomm->settings || is_first) { + spi_xcomm->settings = settings; + status = spi_xcomm_sync_config(spi_xcomm, 0); + if (status < 0) + break; + } + + if (t->len) { + status = spi_xcomm_txrx_bufs(spi_xcomm, spi, t); + + if (status < 0) + break; + + if (status > 0) + msg->actual_length += status; + } + status = 0; + + if (t->delay_usecs) + udelay(t->delay_usecs); + + is_first = false; + } + + if (status != 0 || !cs_change) + spi_xcomm_chipselect(spi_xcomm, spi, false); + + msg->status = status; + spi_finalize_current_message(master); + + return status; +} + +static int spi_xcomm_probe(struct i2c_client *i2c, + const struct i2c_device_id *id) +{ + struct spi_xcomm *spi_xcomm; + struct spi_master *master; + int ret; + + master = spi_alloc_master(&i2c->dev, sizeof(*spi_xcomm)); + if (!master) + return -ENOMEM; + + spi_xcomm = spi_master_get_devdata(master); + spi_xcomm->i2c = i2c; + + master->num_chipselect = 16; + master->mode_bits = SPI_CPHA | SPI_CPOL | SPI_3WIRE; + master->bits_per_word_mask = SPI_BPW_MASK(8); + master->flags = SPI_MASTER_HALF_DUPLEX; + master->transfer_one_message = spi_xcomm_transfer_one; + master->dev.of_node = i2c->dev.of_node; + i2c_set_clientdata(i2c, master); + + ret = devm_spi_register_master(&i2c->dev, master); + if (ret < 0) + spi_master_put(master); + + return ret; +} + +static const struct i2c_device_id spi_xcomm_ids[] = { + { "spi-xcomm" }, + { }, +}; + +static struct i2c_driver spi_xcomm_driver = { + .driver = { + .name = "spi-xcomm", + .owner = THIS_MODULE, + }, + .id_table = spi_xcomm_ids, + .probe = spi_xcomm_probe, +}; +module_i2c_driver(spi_xcomm_driver); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>"); +MODULE_DESCRIPTION("Analog Devices AD-FMCOMMS1-EBZ board I2C-SPI bridge driver"); diff --git a/drivers/spi/spi-xilinx.c b/drivers/spi/spi-xilinx.c new file mode 100644 index 000000000..133f53a9c --- /dev/null +++ b/drivers/spi/spi-xilinx.c @@ -0,0 +1,509 @@ +/* + * Xilinx SPI controller driver (master mode only) + * + * Author: MontaVista Software, Inc. + * source@mvista.com + * + * Copyright (c) 2010 Secret Lab Technologies, Ltd. + * Copyright (c) 2009 Intel Corporation + * 2002-2007 (c) MontaVista Software, Inc. + + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/module.h> +#include <linux/interrupt.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/spi/spi.h> +#include <linux/spi/spi_bitbang.h> +#include <linux/spi/xilinx_spi.h> +#include <linux/io.h> + +#define XILINX_SPI_MAX_CS 32 + +#define XILINX_SPI_NAME "xilinx_spi" + +/* Register definitions as per "OPB Serial Peripheral Interface (SPI) (v1.00e) + * Product Specification", DS464 + */ +#define XSPI_CR_OFFSET 0x60 /* Control Register */ + +#define XSPI_CR_LOOP 0x01 +#define XSPI_CR_ENABLE 0x02 +#define XSPI_CR_MASTER_MODE 0x04 +#define XSPI_CR_CPOL 0x08 +#define XSPI_CR_CPHA 0x10 +#define XSPI_CR_MODE_MASK (XSPI_CR_CPHA | XSPI_CR_CPOL | \ + XSPI_CR_LSB_FIRST | XSPI_CR_LOOP) +#define XSPI_CR_TXFIFO_RESET 0x20 +#define XSPI_CR_RXFIFO_RESET 0x40 +#define XSPI_CR_MANUAL_SSELECT 0x80 +#define XSPI_CR_TRANS_INHIBIT 0x100 +#define XSPI_CR_LSB_FIRST 0x200 + +#define XSPI_SR_OFFSET 0x64 /* Status Register */ + +#define XSPI_SR_RX_EMPTY_MASK 0x01 /* Receive FIFO is empty */ +#define XSPI_SR_RX_FULL_MASK 0x02 /* Receive FIFO is full */ +#define XSPI_SR_TX_EMPTY_MASK 0x04 /* Transmit FIFO is empty */ +#define XSPI_SR_TX_FULL_MASK 0x08 /* Transmit FIFO is full */ +#define XSPI_SR_MODE_FAULT_MASK 0x10 /* Mode fault error */ + +#define XSPI_TXD_OFFSET 0x68 /* Data Transmit Register */ +#define XSPI_RXD_OFFSET 0x6c /* Data Receive Register */ + +#define XSPI_SSR_OFFSET 0x70 /* 32-bit Slave Select Register */ + +/* Register definitions as per "OPB IPIF (v3.01c) Product Specification", DS414 + * IPIF registers are 32 bit + */ +#define XIPIF_V123B_DGIER_OFFSET 0x1c /* IPIF global int enable reg */ +#define XIPIF_V123B_GINTR_ENABLE 0x80000000 + +#define XIPIF_V123B_IISR_OFFSET 0x20 /* IPIF interrupt status reg */ +#define XIPIF_V123B_IIER_OFFSET 0x28 /* IPIF interrupt enable reg */ + +#define XSPI_INTR_MODE_FAULT 0x01 /* Mode fault error */ +#define XSPI_INTR_SLAVE_MODE_FAULT 0x02 /* Selected as slave while + * disabled */ +#define XSPI_INTR_TX_EMPTY 0x04 /* TxFIFO is empty */ +#define XSPI_INTR_TX_UNDERRUN 0x08 /* TxFIFO was underrun */ +#define XSPI_INTR_RX_FULL 0x10 /* RxFIFO is full */ +#define XSPI_INTR_RX_OVERRUN 0x20 /* RxFIFO was overrun */ +#define XSPI_INTR_TX_HALF_EMPTY 0x40 /* TxFIFO is half empty */ + +#define XIPIF_V123B_RESETR_OFFSET 0x40 /* IPIF reset register */ +#define XIPIF_V123B_RESET_MASK 0x0a /* the value to write */ + +struct xilinx_spi { + /* bitbang has to be first */ + struct spi_bitbang bitbang; + struct completion done; + void __iomem *regs; /* virt. address of the control registers */ + + int irq; + + u8 *rx_ptr; /* pointer in the Tx buffer */ + const u8 *tx_ptr; /* pointer in the Rx buffer */ + u8 bytes_per_word; + int buffer_size; /* buffer size in words */ + u32 cs_inactive; /* Level of the CS pins when inactive*/ + unsigned int (*read_fn)(void __iomem *); + void (*write_fn)(u32, void __iomem *); +}; + +static void xspi_write32(u32 val, void __iomem *addr) +{ + iowrite32(val, addr); +} + +static unsigned int xspi_read32(void __iomem *addr) +{ + return ioread32(addr); +} + +static void xspi_write32_be(u32 val, void __iomem *addr) +{ + iowrite32be(val, addr); +} + +static unsigned int xspi_read32_be(void __iomem *addr) +{ + return ioread32be(addr); +} + +static void xilinx_spi_tx(struct xilinx_spi *xspi) +{ + u32 data = 0; + + if (!xspi->tx_ptr) { + xspi->write_fn(0, xspi->regs + XSPI_TXD_OFFSET); + return; + } + + switch (xspi->bytes_per_word) { + case 1: + data = *(u8 *)(xspi->tx_ptr); + break; + case 2: + data = *(u16 *)(xspi->tx_ptr); + break; + case 4: + data = *(u32 *)(xspi->tx_ptr); + break; + } + + xspi->write_fn(data, xspi->regs + XSPI_TXD_OFFSET); + xspi->tx_ptr += xspi->bytes_per_word; +} + +static void xilinx_spi_rx(struct xilinx_spi *xspi) +{ + u32 data = xspi->read_fn(xspi->regs + XSPI_RXD_OFFSET); + + if (!xspi->rx_ptr) + return; + + switch (xspi->bytes_per_word) { + case 1: + *(u8 *)(xspi->rx_ptr) = data; + break; + case 2: + *(u16 *)(xspi->rx_ptr) = data; + break; + case 4: + *(u32 *)(xspi->rx_ptr) = data; + break; + } + + xspi->rx_ptr += xspi->bytes_per_word; +} + +static void xspi_init_hw(struct xilinx_spi *xspi) +{ + void __iomem *regs_base = xspi->regs; + + /* Reset the SPI device */ + xspi->write_fn(XIPIF_V123B_RESET_MASK, + regs_base + XIPIF_V123B_RESETR_OFFSET); + /* Enable the transmit empty interrupt, which we use to determine + * progress on the transmission. + */ + xspi->write_fn(XSPI_INTR_TX_EMPTY, + regs_base + XIPIF_V123B_IIER_OFFSET); + /* Disable the global IPIF interrupt */ + xspi->write_fn(0, regs_base + XIPIF_V123B_DGIER_OFFSET); + /* Deselect the slave on the SPI bus */ + xspi->write_fn(0xffff, regs_base + XSPI_SSR_OFFSET); + /* Disable the transmitter, enable Manual Slave Select Assertion, + * put SPI controller into master mode, and enable it */ + xspi->write_fn(XSPI_CR_MANUAL_SSELECT | XSPI_CR_MASTER_MODE | + XSPI_CR_ENABLE | XSPI_CR_TXFIFO_RESET | XSPI_CR_RXFIFO_RESET, + regs_base + XSPI_CR_OFFSET); +} + +static void xilinx_spi_chipselect(struct spi_device *spi, int is_on) +{ + struct xilinx_spi *xspi = spi_master_get_devdata(spi->master); + u16 cr; + u32 cs; + + if (is_on == BITBANG_CS_INACTIVE) { + /* Deselect the slave on the SPI bus */ + xspi->write_fn(xspi->cs_inactive, xspi->regs + XSPI_SSR_OFFSET); + return; + } + + /* Set the SPI clock phase and polarity */ + cr = xspi->read_fn(xspi->regs + XSPI_CR_OFFSET) & ~XSPI_CR_MODE_MASK; + if (spi->mode & SPI_CPHA) + cr |= XSPI_CR_CPHA; + if (spi->mode & SPI_CPOL) + cr |= XSPI_CR_CPOL; + if (spi->mode & SPI_LSB_FIRST) + cr |= XSPI_CR_LSB_FIRST; + if (spi->mode & SPI_LOOP) + cr |= XSPI_CR_LOOP; + xspi->write_fn(cr, xspi->regs + XSPI_CR_OFFSET); + + /* We do not check spi->max_speed_hz here as the SPI clock + * frequency is not software programmable (the IP block design + * parameter) + */ + + cs = xspi->cs_inactive; + cs ^= BIT(spi->chip_select); + + /* Activate the chip select */ + xspi->write_fn(cs, xspi->regs + XSPI_SSR_OFFSET); +} + +/* spi_bitbang requires custom setup_transfer() to be defined if there is a + * custom txrx_bufs(). + */ +static int xilinx_spi_setup_transfer(struct spi_device *spi, + struct spi_transfer *t) +{ + struct xilinx_spi *xspi = spi_master_get_devdata(spi->master); + + if (spi->mode & SPI_CS_HIGH) + xspi->cs_inactive &= ~BIT(spi->chip_select); + else + xspi->cs_inactive |= BIT(spi->chip_select); + + return 0; +} + +static int xilinx_spi_txrx_bufs(struct spi_device *spi, struct spi_transfer *t) +{ + struct xilinx_spi *xspi = spi_master_get_devdata(spi->master); + int remaining_words; /* the number of words left to transfer */ + bool use_irq = false; + u16 cr = 0; + + /* We get here with transmitter inhibited */ + + xspi->tx_ptr = t->tx_buf; + xspi->rx_ptr = t->rx_buf; + remaining_words = t->len / xspi->bytes_per_word; + reinit_completion(&xspi->done); + + if (xspi->irq >= 0 && remaining_words > xspi->buffer_size) { + use_irq = true; + xspi->write_fn(XSPI_INTR_TX_EMPTY, + xspi->regs + XIPIF_V123B_IISR_OFFSET); + /* Enable the global IPIF interrupt */ + xspi->write_fn(XIPIF_V123B_GINTR_ENABLE, + xspi->regs + XIPIF_V123B_DGIER_OFFSET); + /* Inhibit irq to avoid spurious irqs on tx_empty*/ + cr = xspi->read_fn(xspi->regs + XSPI_CR_OFFSET); + xspi->write_fn(cr | XSPI_CR_TRANS_INHIBIT, + xspi->regs + XSPI_CR_OFFSET); + } + + while (remaining_words) { + int n_words, tx_words, rx_words; + + n_words = min(remaining_words, xspi->buffer_size); + + tx_words = n_words; + while (tx_words--) + xilinx_spi_tx(xspi); + + /* Start the transfer by not inhibiting the transmitter any + * longer + */ + + if (use_irq) { + xspi->write_fn(cr, xspi->regs + XSPI_CR_OFFSET); + wait_for_completion(&xspi->done); + } else + while (!(xspi->read_fn(xspi->regs + XSPI_SR_OFFSET) & + XSPI_SR_TX_EMPTY_MASK)) + ; + + /* A transmit has just completed. Process received data and + * check for more data to transmit. Always inhibit the + * transmitter while the Isr refills the transmit register/FIFO, + * or make sure it is stopped if we're done. + */ + if (use_irq) + xspi->write_fn(cr | XSPI_CR_TRANS_INHIBIT, + xspi->regs + XSPI_CR_OFFSET); + + /* Read out all the data from the Rx FIFO */ + rx_words = n_words; + while (rx_words--) + xilinx_spi_rx(xspi); + + remaining_words -= n_words; + } + + if (use_irq) + xspi->write_fn(0, xspi->regs + XIPIF_V123B_DGIER_OFFSET); + + return t->len; +} + + +/* This driver supports single master mode only. Hence Tx FIFO Empty + * is the only interrupt we care about. + * Receive FIFO Overrun, Transmit FIFO Underrun, Mode Fault, and Slave Mode + * Fault are not to happen. + */ +static irqreturn_t xilinx_spi_irq(int irq, void *dev_id) +{ + struct xilinx_spi *xspi = dev_id; + u32 ipif_isr; + + /* Get the IPIF interrupts, and clear them immediately */ + ipif_isr = xspi->read_fn(xspi->regs + XIPIF_V123B_IISR_OFFSET); + xspi->write_fn(ipif_isr, xspi->regs + XIPIF_V123B_IISR_OFFSET); + + if (ipif_isr & XSPI_INTR_TX_EMPTY) { /* Transmission completed */ + complete(&xspi->done); + } + + return IRQ_HANDLED; +} + +static int xilinx_spi_find_buffer_size(struct xilinx_spi *xspi) +{ + u8 sr; + int n_words = 0; + + /* + * Before the buffer_size detection we reset the core + * to make sure we start with a clean state. + */ + xspi->write_fn(XIPIF_V123B_RESET_MASK, + xspi->regs + XIPIF_V123B_RESETR_OFFSET); + + /* Fill the Tx FIFO with as many words as possible */ + do { + xspi->write_fn(0, xspi->regs + XSPI_TXD_OFFSET); + sr = xspi->read_fn(xspi->regs + XSPI_SR_OFFSET); + n_words++; + } while (!(sr & XSPI_SR_TX_FULL_MASK)); + + return n_words; +} + +static const struct of_device_id xilinx_spi_of_match[] = { + { .compatible = "xlnx,xps-spi-2.00.a", }, + { .compatible = "xlnx,xps-spi-2.00.b", }, + {} +}; +MODULE_DEVICE_TABLE(of, xilinx_spi_of_match); + +static int xilinx_spi_probe(struct platform_device *pdev) +{ + struct xilinx_spi *xspi; + struct xspi_platform_data *pdata; + struct resource *res; + int ret, num_cs = 0, bits_per_word = 8; + struct spi_master *master; + u32 tmp; + u8 i; + + pdata = dev_get_platdata(&pdev->dev); + if (pdata) { + num_cs = pdata->num_chipselect; + bits_per_word = pdata->bits_per_word; + } else { + of_property_read_u32(pdev->dev.of_node, "xlnx,num-ss-bits", + &num_cs); + } + + if (!num_cs) { + dev_err(&pdev->dev, + "Missing slave select configuration data\n"); + return -EINVAL; + } + + if (num_cs > XILINX_SPI_MAX_CS) { + dev_err(&pdev->dev, "Invalid number of spi slaves\n"); + return -EINVAL; + } + + master = spi_alloc_master(&pdev->dev, sizeof(struct xilinx_spi)); + if (!master) + return -ENODEV; + + /* the spi->mode bits understood by this driver: */ + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST | SPI_LOOP | + SPI_CS_HIGH; + + xspi = spi_master_get_devdata(master); + xspi->cs_inactive = 0xffffffff; + xspi->bitbang.master = master; + xspi->bitbang.chipselect = xilinx_spi_chipselect; + xspi->bitbang.setup_transfer = xilinx_spi_setup_transfer; + xspi->bitbang.txrx_bufs = xilinx_spi_txrx_bufs; + init_completion(&xspi->done); + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + xspi->regs = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(xspi->regs)) { + ret = PTR_ERR(xspi->regs); + goto put_master; + } + + master->bus_num = pdev->id; + master->num_chipselect = num_cs; + master->dev.of_node = pdev->dev.of_node; + + /* + * Detect endianess on the IP via loop bit in CR. Detection + * must be done before reset is sent because incorrect reset + * value generates error interrupt. + * Setup little endian helper functions first and try to use them + * and check if bit was correctly setup or not. + */ + xspi->read_fn = xspi_read32; + xspi->write_fn = xspi_write32; + + xspi->write_fn(XSPI_CR_LOOP, xspi->regs + XSPI_CR_OFFSET); + tmp = xspi->read_fn(xspi->regs + XSPI_CR_OFFSET); + tmp &= XSPI_CR_LOOP; + if (tmp != XSPI_CR_LOOP) { + xspi->read_fn = xspi_read32_be; + xspi->write_fn = xspi_write32_be; + } + + master->bits_per_word_mask = SPI_BPW_MASK(bits_per_word); + xspi->bytes_per_word = bits_per_word / 8; + xspi->buffer_size = xilinx_spi_find_buffer_size(xspi); + + xspi->irq = platform_get_irq(pdev, 0); + if (xspi->irq >= 0) { + /* Register for SPI Interrupt */ + ret = devm_request_irq(&pdev->dev, xspi->irq, xilinx_spi_irq, 0, + dev_name(&pdev->dev), xspi); + if (ret) + goto put_master; + } + + /* SPI controller initializations */ + xspi_init_hw(xspi); + + ret = spi_bitbang_start(&xspi->bitbang); + if (ret) { + dev_err(&pdev->dev, "spi_bitbang_start FAILED\n"); + goto put_master; + } + + dev_info(&pdev->dev, "at 0x%08llX mapped to 0x%p, irq=%d\n", + (unsigned long long)res->start, xspi->regs, xspi->irq); + + if (pdata) { + for (i = 0; i < pdata->num_devices; i++) + spi_new_device(master, pdata->devices + i); + } + + platform_set_drvdata(pdev, master); + return 0; + +put_master: + spi_master_put(master); + + return ret; +} + +static int xilinx_spi_remove(struct platform_device *pdev) +{ + struct spi_master *master = platform_get_drvdata(pdev); + struct xilinx_spi *xspi = spi_master_get_devdata(master); + void __iomem *regs_base = xspi->regs; + + spi_bitbang_stop(&xspi->bitbang); + + /* Disable all the interrupts just in case */ + xspi->write_fn(0, regs_base + XIPIF_V123B_IIER_OFFSET); + /* Disable the global IPIF interrupt */ + xspi->write_fn(0, regs_base + XIPIF_V123B_DGIER_OFFSET); + + spi_master_put(xspi->bitbang.master); + + return 0; +} + +/* work with hotplug and coldplug */ +MODULE_ALIAS("platform:" XILINX_SPI_NAME); + +static struct platform_driver xilinx_spi_driver = { + .probe = xilinx_spi_probe, + .remove = xilinx_spi_remove, + .driver = { + .name = XILINX_SPI_NAME, + .of_match_table = xilinx_spi_of_match, + }, +}; +module_platform_driver(xilinx_spi_driver); + +MODULE_AUTHOR("MontaVista Software, Inc. <source@mvista.com>"); +MODULE_DESCRIPTION("Xilinx SPI driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/spi/spi-xtensa-xtfpga.c b/drivers/spi/spi-xtensa-xtfpga.c new file mode 100644 index 000000000..2e32ea2f1 --- /dev/null +++ b/drivers/spi/spi-xtensa-xtfpga.c @@ -0,0 +1,170 @@ +/* + * Xtensa xtfpga SPI controller driver + * + * Copyright (c) 2014 Cadence Design Systems Inc. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/delay.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/spi/spi.h> +#include <linux/spi/spi_bitbang.h> + +#define XTFPGA_SPI_NAME "xtfpga_spi" + +#define XTFPGA_SPI_START 0x0 +#define XTFPGA_SPI_BUSY 0x4 +#define XTFPGA_SPI_DATA 0x8 + +#define BUSY_WAIT_US 100 + +struct xtfpga_spi { + struct spi_bitbang bitbang; + void __iomem *regs; + u32 data; + unsigned data_sz; +}; + +static inline void xtfpga_spi_write32(const struct xtfpga_spi *spi, + unsigned addr, u32 val) +{ + iowrite32(val, spi->regs + addr); +} + +static inline unsigned int xtfpga_spi_read32(const struct xtfpga_spi *spi, + unsigned addr) +{ + return ioread32(spi->regs + addr); +} + +static inline void xtfpga_spi_wait_busy(struct xtfpga_spi *xspi) +{ + unsigned i; + + for (i = 0; xtfpga_spi_read32(xspi, XTFPGA_SPI_BUSY) && + i < BUSY_WAIT_US; ++i) + udelay(1); + WARN_ON_ONCE(i == BUSY_WAIT_US); +} + +static u32 xtfpga_spi_txrx_word(struct spi_device *spi, unsigned nsecs, + u32 v, u8 bits) +{ + struct xtfpga_spi *xspi = spi_master_get_devdata(spi->master); + + xspi->data = (xspi->data << bits) | (v & GENMASK(bits - 1, 0)); + xspi->data_sz += bits; + if (xspi->data_sz >= 16) { + xtfpga_spi_write32(xspi, XTFPGA_SPI_DATA, + xspi->data >> (xspi->data_sz - 16)); + xspi->data_sz -= 16; + xtfpga_spi_write32(xspi, XTFPGA_SPI_START, 1); + xtfpga_spi_wait_busy(xspi); + xtfpga_spi_write32(xspi, XTFPGA_SPI_START, 0); + } + + return 0; +} + +static void xtfpga_spi_chipselect(struct spi_device *spi, int is_on) +{ + struct xtfpga_spi *xspi = spi_master_get_devdata(spi->master); + + WARN_ON(xspi->data_sz != 0); + xspi->data_sz = 0; +} + +static int xtfpga_spi_probe(struct platform_device *pdev) +{ + struct xtfpga_spi *xspi; + struct resource *mem; + int ret; + struct spi_master *master; + + master = spi_alloc_master(&pdev->dev, sizeof(struct xtfpga_spi)); + if (!master) + return -ENOMEM; + + master->flags = SPI_MASTER_NO_RX; + master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 16); + master->bus_num = pdev->dev.id; + master->dev.of_node = pdev->dev.of_node; + + xspi = spi_master_get_devdata(master); + xspi->bitbang.master = master; + xspi->bitbang.chipselect = xtfpga_spi_chipselect; + xspi->bitbang.txrx_word[SPI_MODE_0] = xtfpga_spi_txrx_word; + + mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!mem) { + dev_err(&pdev->dev, "No memory resource\n"); + ret = -ENODEV; + goto err; + } + xspi->regs = devm_ioremap_resource(&pdev->dev, mem); + if (IS_ERR(xspi->regs)) { + ret = PTR_ERR(xspi->regs); + goto err; + } + + xtfpga_spi_write32(xspi, XTFPGA_SPI_START, 0); + usleep_range(1000, 2000); + if (xtfpga_spi_read32(xspi, XTFPGA_SPI_BUSY)) { + dev_err(&pdev->dev, "Device stuck in busy state\n"); + ret = -EBUSY; + goto err; + } + + ret = spi_bitbang_start(&xspi->bitbang); + if (ret < 0) { + dev_err(&pdev->dev, "spi_bitbang_start failed\n"); + goto err; + } + + platform_set_drvdata(pdev, master); + return 0; +err: + spi_master_put(master); + return ret; +} + +static int xtfpga_spi_remove(struct platform_device *pdev) +{ + struct spi_master *master = platform_get_drvdata(pdev); + struct xtfpga_spi *xspi = spi_master_get_devdata(master); + + spi_bitbang_stop(&xspi->bitbang); + spi_master_put(master); + + return 0; +} + +MODULE_ALIAS("platform:" XTFPGA_SPI_NAME); + +#ifdef CONFIG_OF +static const struct of_device_id xtfpga_spi_of_match[] = { + { .compatible = "cdns,xtfpga-spi", }, + {} +}; +MODULE_DEVICE_TABLE(of, xtfpga_spi_of_match); +#endif + +static struct platform_driver xtfpga_spi_driver = { + .probe = xtfpga_spi_probe, + .remove = xtfpga_spi_remove, + .driver = { + .name = XTFPGA_SPI_NAME, + .of_match_table = of_match_ptr(xtfpga_spi_of_match), + }, +}; +module_platform_driver(xtfpga_spi_driver); + +MODULE_AUTHOR("Max Filippov <jcmvbkbc@gmail.com>"); +MODULE_DESCRIPTION("xtensa xtfpga SPI driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c new file mode 100644 index 000000000..d35c1a132 --- /dev/null +++ b/drivers/spi/spi.c @@ -0,0 +1,2408 @@ +/* + * SPI init/core code + * + * Copyright (C) 2005 David Brownell + * Copyright (C) 2008 Secret Lab Technologies Ltd. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/kernel.h> +#include <linux/device.h> +#include <linux/init.h> +#include <linux/cache.h> +#include <linux/dma-mapping.h> +#include <linux/dmaengine.h> +#include <linux/mutex.h> +#include <linux/of_device.h> +#include <linux/of_irq.h> +#include <linux/clk/clk-conf.h> +#include <linux/slab.h> +#include <linux/mod_devicetable.h> +#include <linux/spi/spi.h> +#include <linux/of_gpio.h> +#include <linux/pm_runtime.h> +#include <linux/pm_domain.h> +#include <linux/export.h> +#include <linux/sched/rt.h> +#include <linux/delay.h> +#include <linux/kthread.h> +#include <linux/ioport.h> +#include <linux/acpi.h> + +#define CREATE_TRACE_POINTS +#include <trace/events/spi.h> + +static void spidev_release(struct device *dev) +{ + struct spi_device *spi = to_spi_device(dev); + + /* spi masters may cleanup for released devices */ + if (spi->master->cleanup) + spi->master->cleanup(spi); + + spi_master_put(spi->master); + kfree(spi); +} + +static ssize_t +modalias_show(struct device *dev, struct device_attribute *a, char *buf) +{ + const struct spi_device *spi = to_spi_device(dev); + int len; + + len = acpi_device_modalias(dev, buf, PAGE_SIZE - 1); + if (len != -ENODEV) + return len; + + return sprintf(buf, "%s%s\n", SPI_MODULE_PREFIX, spi->modalias); +} +static DEVICE_ATTR_RO(modalias); + +static struct attribute *spi_dev_attrs[] = { + &dev_attr_modalias.attr, + NULL, +}; +ATTRIBUTE_GROUPS(spi_dev); + +/* modalias support makes "modprobe $MODALIAS" new-style hotplug work, + * and the sysfs version makes coldplug work too. + */ + +static const struct spi_device_id *spi_match_id(const struct spi_device_id *id, + const struct spi_device *sdev) +{ + while (id->name[0]) { + if (!strcmp(sdev->modalias, id->name)) + return id; + id++; + } + return NULL; +} + +const struct spi_device_id *spi_get_device_id(const struct spi_device *sdev) +{ + const struct spi_driver *sdrv = to_spi_driver(sdev->dev.driver); + + return spi_match_id(sdrv->id_table, sdev); +} +EXPORT_SYMBOL_GPL(spi_get_device_id); + +static int spi_match_device(struct device *dev, struct device_driver *drv) +{ + const struct spi_device *spi = to_spi_device(dev); + const struct spi_driver *sdrv = to_spi_driver(drv); + + /* Attempt an OF style match */ + if (of_driver_match_device(dev, drv)) + return 1; + + /* Then try ACPI */ + if (acpi_driver_match_device(dev, drv)) + return 1; + + if (sdrv->id_table) + return !!spi_match_id(sdrv->id_table, spi); + + return strcmp(spi->modalias, drv->name) == 0; +} + +static int spi_uevent(struct device *dev, struct kobj_uevent_env *env) +{ + const struct spi_device *spi = to_spi_device(dev); + int rc; + + rc = acpi_device_uevent_modalias(dev, env); + if (rc != -ENODEV) + return rc; + + add_uevent_var(env, "MODALIAS=%s%s", SPI_MODULE_PREFIX, spi->modalias); + return 0; +} + +struct bus_type spi_bus_type = { + .name = "spi", + .dev_groups = spi_dev_groups, + .match = spi_match_device, + .uevent = spi_uevent, +}; +EXPORT_SYMBOL_GPL(spi_bus_type); + + +static int spi_drv_probe(struct device *dev) +{ + const struct spi_driver *sdrv = to_spi_driver(dev->driver); + int ret; + + ret = of_clk_set_defaults(dev->of_node, false); + if (ret) + return ret; + + ret = dev_pm_domain_attach(dev, true); + if (ret != -EPROBE_DEFER) { + ret = sdrv->probe(to_spi_device(dev)); + if (ret) + dev_pm_domain_detach(dev, true); + } + + return ret; +} + +static int spi_drv_remove(struct device *dev) +{ + const struct spi_driver *sdrv = to_spi_driver(dev->driver); + int ret; + + ret = sdrv->remove(to_spi_device(dev)); + dev_pm_domain_detach(dev, true); + + return ret; +} + +static void spi_drv_shutdown(struct device *dev) +{ + const struct spi_driver *sdrv = to_spi_driver(dev->driver); + + sdrv->shutdown(to_spi_device(dev)); +} + +/** + * spi_register_driver - register a SPI driver + * @sdrv: the driver to register + * Context: can sleep + */ +int spi_register_driver(struct spi_driver *sdrv) +{ + sdrv->driver.bus = &spi_bus_type; + if (sdrv->probe) + sdrv->driver.probe = spi_drv_probe; + if (sdrv->remove) + sdrv->driver.remove = spi_drv_remove; + if (sdrv->shutdown) + sdrv->driver.shutdown = spi_drv_shutdown; + return driver_register(&sdrv->driver); +} +EXPORT_SYMBOL_GPL(spi_register_driver); + +/*-------------------------------------------------------------------------*/ + +/* SPI devices should normally not be created by SPI device drivers; that + * would make them board-specific. Similarly with SPI master drivers. + * Device registration normally goes into like arch/.../mach.../board-YYY.c + * with other readonly (flashable) information about mainboard devices. + */ + +struct boardinfo { + struct list_head list; + struct spi_board_info board_info; +}; + +static LIST_HEAD(board_list); +static LIST_HEAD(spi_master_list); + +/* + * Used to protect add/del opertion for board_info list and + * spi_master list, and their matching process + */ +static DEFINE_MUTEX(board_lock); + +/** + * spi_alloc_device - Allocate a new SPI device + * @master: Controller to which device is connected + * Context: can sleep + * + * Allows a driver to allocate and initialize a spi_device without + * registering it immediately. This allows a driver to directly + * fill the spi_device with device parameters before calling + * spi_add_device() on it. + * + * Caller is responsible to call spi_add_device() on the returned + * spi_device structure to add it to the SPI master. If the caller + * needs to discard the spi_device without adding it, then it should + * call spi_dev_put() on it. + * + * Returns a pointer to the new device, or NULL. + */ +struct spi_device *spi_alloc_device(struct spi_master *master) +{ + struct spi_device *spi; + + if (!spi_master_get(master)) + return NULL; + + spi = kzalloc(sizeof(*spi), GFP_KERNEL); + if (!spi) { + spi_master_put(master); + return NULL; + } + + spi->master = master; + spi->dev.parent = &master->dev; + spi->dev.bus = &spi_bus_type; + spi->dev.release = spidev_release; + spi->cs_gpio = -ENOENT; + device_initialize(&spi->dev); + return spi; +} +EXPORT_SYMBOL_GPL(spi_alloc_device); + +static void spi_dev_set_name(struct spi_device *spi) +{ + struct acpi_device *adev = ACPI_COMPANION(&spi->dev); + + if (adev) { + dev_set_name(&spi->dev, "spi-%s", acpi_dev_name(adev)); + return; + } + + dev_set_name(&spi->dev, "%s.%u", dev_name(&spi->master->dev), + spi->chip_select); +} + +static int spi_dev_check(struct device *dev, void *data) +{ + struct spi_device *spi = to_spi_device(dev); + struct spi_device *new_spi = data; + + if (spi->master == new_spi->master && + spi->chip_select == new_spi->chip_select) + return -EBUSY; + return 0; +} + +/** + * spi_add_device - Add spi_device allocated with spi_alloc_device + * @spi: spi_device to register + * + * Companion function to spi_alloc_device. Devices allocated with + * spi_alloc_device can be added onto the spi bus with this function. + * + * Returns 0 on success; negative errno on failure + */ +int spi_add_device(struct spi_device *spi) +{ + static DEFINE_MUTEX(spi_add_lock); + struct spi_master *master = spi->master; + struct device *dev = master->dev.parent; + int status; + + /* Chipselects are numbered 0..max; validate. */ + if (spi->chip_select >= master->num_chipselect) { + dev_err(dev, "cs%d >= max %d\n", + spi->chip_select, + master->num_chipselect); + return -EINVAL; + } + + /* Set the bus ID string */ + spi_dev_set_name(spi); + + /* We need to make sure there's no other device with this + * chipselect **BEFORE** we call setup(), else we'll trash + * its configuration. Lock against concurrent add() calls. + */ + mutex_lock(&spi_add_lock); + + status = bus_for_each_dev(&spi_bus_type, NULL, spi, spi_dev_check); + if (status) { + dev_err(dev, "chipselect %d already in use\n", + spi->chip_select); + goto done; + } + + if (master->cs_gpios) + spi->cs_gpio = master->cs_gpios[spi->chip_select]; + + /* Drivers may modify this initial i/o setup, but will + * normally rely on the device being setup. Devices + * using SPI_CS_HIGH can't coexist well otherwise... + */ + status = spi_setup(spi); + if (status < 0) { + dev_err(dev, "can't setup %s, status %d\n", + dev_name(&spi->dev), status); + goto done; + } + + /* Device may be bound to an active driver when this returns */ + status = device_add(&spi->dev); + if (status < 0) + dev_err(dev, "can't add %s, status %d\n", + dev_name(&spi->dev), status); + else + dev_dbg(dev, "registered child %s\n", dev_name(&spi->dev)); + +done: + mutex_unlock(&spi_add_lock); + return status; +} +EXPORT_SYMBOL_GPL(spi_add_device); + +/** + * spi_new_device - instantiate one new SPI device + * @master: Controller to which device is connected + * @chip: Describes the SPI device + * Context: can sleep + * + * On typical mainboards, this is purely internal; and it's not needed + * after board init creates the hard-wired devices. Some development + * platforms may not be able to use spi_register_board_info though, and + * this is exported so that for example a USB or parport based adapter + * driver could add devices (which it would learn about out-of-band). + * + * Returns the new device, or NULL. + */ +struct spi_device *spi_new_device(struct spi_master *master, + struct spi_board_info *chip) +{ + struct spi_device *proxy; + int status; + + /* NOTE: caller did any chip->bus_num checks necessary. + * + * Also, unless we change the return value convention to use + * error-or-pointer (not NULL-or-pointer), troubleshootability + * suggests syslogged diagnostics are best here (ugh). + */ + + proxy = spi_alloc_device(master); + if (!proxy) + return NULL; + + WARN_ON(strlen(chip->modalias) >= sizeof(proxy->modalias)); + + proxy->chip_select = chip->chip_select; + proxy->max_speed_hz = chip->max_speed_hz; + proxy->mode = chip->mode; + proxy->irq = chip->irq; + strlcpy(proxy->modalias, chip->modalias, sizeof(proxy->modalias)); + proxy->dev.platform_data = (void *) chip->platform_data; + proxy->controller_data = chip->controller_data; + proxy->controller_state = NULL; + + status = spi_add_device(proxy); + if (status < 0) { + spi_dev_put(proxy); + return NULL; + } + + return proxy; +} +EXPORT_SYMBOL_GPL(spi_new_device); + +static void spi_match_master_to_boardinfo(struct spi_master *master, + struct spi_board_info *bi) +{ + struct spi_device *dev; + + if (master->bus_num != bi->bus_num) + return; + + dev = spi_new_device(master, bi); + if (!dev) + dev_err(master->dev.parent, "can't create new device for %s\n", + bi->modalias); +} + +/** + * spi_register_board_info - register SPI devices for a given board + * @info: array of chip descriptors + * @n: how many descriptors are provided + * Context: can sleep + * + * Board-specific early init code calls this (probably during arch_initcall) + * with segments of the SPI device table. Any device nodes are created later, + * after the relevant parent SPI controller (bus_num) is defined. We keep + * this table of devices forever, so that reloading a controller driver will + * not make Linux forget about these hard-wired devices. + * + * Other code can also call this, e.g. a particular add-on board might provide + * SPI devices through its expansion connector, so code initializing that board + * would naturally declare its SPI devices. + * + * The board info passed can safely be __initdata ... but be careful of + * any embedded pointers (platform_data, etc), they're copied as-is. + */ +int spi_register_board_info(struct spi_board_info const *info, unsigned n) +{ + struct boardinfo *bi; + int i; + + if (!n) + return -EINVAL; + + bi = kzalloc(n * sizeof(*bi), GFP_KERNEL); + if (!bi) + return -ENOMEM; + + for (i = 0; i < n; i++, bi++, info++) { + struct spi_master *master; + + memcpy(&bi->board_info, info, sizeof(*info)); + mutex_lock(&board_lock); + list_add_tail(&bi->list, &board_list); + list_for_each_entry(master, &spi_master_list, list) + spi_match_master_to_boardinfo(master, &bi->board_info); + mutex_unlock(&board_lock); + } + + return 0; +} + +/*-------------------------------------------------------------------------*/ + +static void spi_set_cs(struct spi_device *spi, bool enable) +{ + if (spi->mode & SPI_CS_HIGH) + enable = !enable; + + if (spi->cs_gpio >= 0) + gpio_set_value(spi->cs_gpio, !enable); + else if (spi->master->set_cs) + spi->master->set_cs(spi, !enable); +} + +#ifdef CONFIG_HAS_DMA +static int spi_map_buf(struct spi_master *master, struct device *dev, + struct sg_table *sgt, void *buf, size_t len, + enum dma_data_direction dir) +{ + const bool vmalloced_buf = is_vmalloc_addr(buf); + const int desc_len = vmalloced_buf ? PAGE_SIZE : master->max_dma_len; + const int sgs = DIV_ROUND_UP(len, desc_len); + struct page *vm_page; + void *sg_buf; + size_t min; + int i, ret; + + ret = sg_alloc_table(sgt, sgs, GFP_KERNEL); + if (ret != 0) + return ret; + + for (i = 0; i < sgs; i++) { + min = min_t(size_t, len, desc_len); + + if (vmalloced_buf) { + vm_page = vmalloc_to_page(buf); + if (!vm_page) { + sg_free_table(sgt); + return -ENOMEM; + } + sg_set_page(&sgt->sgl[i], vm_page, + min, offset_in_page(buf)); + } else { + sg_buf = buf; + sg_set_buf(&sgt->sgl[i], sg_buf, min); + } + + + buf += min; + len -= min; + } + + ret = dma_map_sg(dev, sgt->sgl, sgt->nents, dir); + if (!ret) + ret = -ENOMEM; + if (ret < 0) { + sg_free_table(sgt); + return ret; + } + + sgt->nents = ret; + + return 0; +} + +static void spi_unmap_buf(struct spi_master *master, struct device *dev, + struct sg_table *sgt, enum dma_data_direction dir) +{ + if (sgt->orig_nents) { + dma_unmap_sg(dev, sgt->sgl, sgt->orig_nents, dir); + sg_free_table(sgt); + } +} + +static int __spi_map_msg(struct spi_master *master, struct spi_message *msg) +{ + struct device *tx_dev, *rx_dev; + struct spi_transfer *xfer; + int ret; + + if (!master->can_dma) + return 0; + + tx_dev = master->dma_tx->device->dev; + rx_dev = master->dma_rx->device->dev; + + list_for_each_entry(xfer, &msg->transfers, transfer_list) { + if (!master->can_dma(master, msg->spi, xfer)) + continue; + + if (xfer->tx_buf != NULL) { + ret = spi_map_buf(master, tx_dev, &xfer->tx_sg, + (void *)xfer->tx_buf, xfer->len, + DMA_TO_DEVICE); + if (ret != 0) + return ret; + } + + if (xfer->rx_buf != NULL) { + ret = spi_map_buf(master, rx_dev, &xfer->rx_sg, + xfer->rx_buf, xfer->len, + DMA_FROM_DEVICE); + if (ret != 0) { + spi_unmap_buf(master, tx_dev, &xfer->tx_sg, + DMA_TO_DEVICE); + return ret; + } + } + } + + master->cur_msg_mapped = true; + + return 0; +} + +static int spi_unmap_msg(struct spi_master *master, struct spi_message *msg) +{ + struct spi_transfer *xfer; + struct device *tx_dev, *rx_dev; + + if (!master->cur_msg_mapped || !master->can_dma) + return 0; + + tx_dev = master->dma_tx->device->dev; + rx_dev = master->dma_rx->device->dev; + + list_for_each_entry(xfer, &msg->transfers, transfer_list) { + /* + * Restore the original value of tx_buf or rx_buf if they are + * NULL. + */ + if (xfer->tx_buf == master->dummy_tx) + xfer->tx_buf = NULL; + if (xfer->rx_buf == master->dummy_rx) + xfer->rx_buf = NULL; + + if (!master->can_dma(master, msg->spi, xfer)) + continue; + + spi_unmap_buf(master, rx_dev, &xfer->rx_sg, DMA_FROM_DEVICE); + spi_unmap_buf(master, tx_dev, &xfer->tx_sg, DMA_TO_DEVICE); + } + + return 0; +} +#else /* !CONFIG_HAS_DMA */ +static inline int __spi_map_msg(struct spi_master *master, + struct spi_message *msg) +{ + return 0; +} + +static inline int spi_unmap_msg(struct spi_master *master, + struct spi_message *msg) +{ + return 0; +} +#endif /* !CONFIG_HAS_DMA */ + +static int spi_map_msg(struct spi_master *master, struct spi_message *msg) +{ + struct spi_transfer *xfer; + void *tmp; + unsigned int max_tx, max_rx; + + if (master->flags & (SPI_MASTER_MUST_RX | SPI_MASTER_MUST_TX)) { + max_tx = 0; + max_rx = 0; + + list_for_each_entry(xfer, &msg->transfers, transfer_list) { + if ((master->flags & SPI_MASTER_MUST_TX) && + !xfer->tx_buf) + max_tx = max(xfer->len, max_tx); + if ((master->flags & SPI_MASTER_MUST_RX) && + !xfer->rx_buf) + max_rx = max(xfer->len, max_rx); + } + + if (max_tx) { + tmp = krealloc(master->dummy_tx, max_tx, + GFP_KERNEL | GFP_DMA); + if (!tmp) + return -ENOMEM; + master->dummy_tx = tmp; + memset(tmp, 0, max_tx); + } + + if (max_rx) { + tmp = krealloc(master->dummy_rx, max_rx, + GFP_KERNEL | GFP_DMA); + if (!tmp) + return -ENOMEM; + master->dummy_rx = tmp; + } + + if (max_tx || max_rx) { + list_for_each_entry(xfer, &msg->transfers, + transfer_list) { + if (!xfer->tx_buf) + xfer->tx_buf = master->dummy_tx; + if (!xfer->rx_buf) + xfer->rx_buf = master->dummy_rx; + } + } + } + + return __spi_map_msg(master, msg); +} + +/* + * spi_transfer_one_message - Default implementation of transfer_one_message() + * + * This is a standard implementation of transfer_one_message() for + * drivers which impelment a transfer_one() operation. It provides + * standard handling of delays and chip select management. + */ +static int spi_transfer_one_message(struct spi_master *master, + struct spi_message *msg) +{ + struct spi_transfer *xfer; + bool keep_cs = false; + int ret = 0; + unsigned long ms = 1; + + spi_set_cs(msg->spi, true); + + list_for_each_entry(xfer, &msg->transfers, transfer_list) { + trace_spi_transfer_start(msg, xfer); + + if (xfer->tx_buf || xfer->rx_buf) { + reinit_completion(&master->xfer_completion); + + ret = master->transfer_one(master, msg->spi, xfer); + if (ret < 0) { + dev_err(&msg->spi->dev, + "SPI transfer failed: %d\n", ret); + goto out; + } + + if (ret > 0) { + ret = 0; + ms = xfer->len * 8 * 1000 / xfer->speed_hz; + ms += ms + 100; /* some tolerance */ + + ms = wait_for_completion_timeout(&master->xfer_completion, + msecs_to_jiffies(ms)); + } + + if (ms == 0) { + dev_err(&msg->spi->dev, + "SPI transfer timed out\n"); + msg->status = -ETIMEDOUT; + } + } else { + if (xfer->len) + dev_err(&msg->spi->dev, + "Bufferless transfer has length %u\n", + xfer->len); + } + + trace_spi_transfer_stop(msg, xfer); + + if (msg->status != -EINPROGRESS) + goto out; + + if (xfer->delay_usecs) + udelay(xfer->delay_usecs); + + if (xfer->cs_change) { + if (list_is_last(&xfer->transfer_list, + &msg->transfers)) { + keep_cs = true; + } else { + spi_set_cs(msg->spi, false); + udelay(10); + spi_set_cs(msg->spi, true); + } + } + + msg->actual_length += xfer->len; + } + +out: + if (ret != 0 || !keep_cs) + spi_set_cs(msg->spi, false); + + if (msg->status == -EINPROGRESS) + msg->status = ret; + + if (msg->status && master->handle_err) + master->handle_err(master, msg); + + spi_finalize_current_message(master); + + return ret; +} + +/** + * spi_finalize_current_transfer - report completion of a transfer + * @master: the master reporting completion + * + * Called by SPI drivers using the core transfer_one_message() + * implementation to notify it that the current interrupt driven + * transfer has finished and the next one may be scheduled. + */ +void spi_finalize_current_transfer(struct spi_master *master) +{ + complete(&master->xfer_completion); +} +EXPORT_SYMBOL_GPL(spi_finalize_current_transfer); + +/** + * __spi_pump_messages - function which processes spi message queue + * @master: master to process queue for + * @in_kthread: true if we are in the context of the message pump thread + * + * This function checks if there is any spi message in the queue that + * needs processing and if so call out to the driver to initialize hardware + * and transfer each message. + * + * Note that it is called both from the kthread itself and also from + * inside spi_sync(); the queue extraction handling at the top of the + * function should deal with this safely. + */ +static void __spi_pump_messages(struct spi_master *master, bool in_kthread) +{ + unsigned long flags; + bool was_busy = false; + int ret; + + /* Lock queue */ + spin_lock_irqsave(&master->queue_lock, flags); + + /* Make sure we are not already running a message */ + if (master->cur_msg) { + spin_unlock_irqrestore(&master->queue_lock, flags); + return; + } + + /* If another context is idling the device then defer */ + if (master->idling) { + queue_kthread_work(&master->kworker, &master->pump_messages); + spin_unlock_irqrestore(&master->queue_lock, flags); + return; + } + + /* Check if the queue is idle */ + if (list_empty(&master->queue) || !master->running) { + if (!master->busy) { + spin_unlock_irqrestore(&master->queue_lock, flags); + return; + } + + /* Only do teardown in the thread */ + if (!in_kthread) { + queue_kthread_work(&master->kworker, + &master->pump_messages); + spin_unlock_irqrestore(&master->queue_lock, flags); + return; + } + + master->busy = false; + master->idling = true; + spin_unlock_irqrestore(&master->queue_lock, flags); + + kfree(master->dummy_rx); + master->dummy_rx = NULL; + kfree(master->dummy_tx); + master->dummy_tx = NULL; + if (master->unprepare_transfer_hardware && + master->unprepare_transfer_hardware(master)) + dev_err(&master->dev, + "failed to unprepare transfer hardware\n"); + if (master->auto_runtime_pm) { + pm_runtime_mark_last_busy(master->dev.parent); + pm_runtime_put_autosuspend(master->dev.parent); + } + trace_spi_master_idle(master); + + spin_lock_irqsave(&master->queue_lock, flags); + master->idling = false; + spin_unlock_irqrestore(&master->queue_lock, flags); + return; + } + + /* Extract head of queue */ + master->cur_msg = + list_first_entry(&master->queue, struct spi_message, queue); + + list_del_init(&master->cur_msg->queue); + if (master->busy) + was_busy = true; + else + master->busy = true; + spin_unlock_irqrestore(&master->queue_lock, flags); + + if (!was_busy && master->auto_runtime_pm) { + ret = pm_runtime_get_sync(master->dev.parent); + if (ret < 0) { + dev_err(&master->dev, "Failed to power device: %d\n", + ret); + return; + } + } + + if (!was_busy) + trace_spi_master_busy(master); + + if (!was_busy && master->prepare_transfer_hardware) { + ret = master->prepare_transfer_hardware(master); + if (ret) { + dev_err(&master->dev, + "failed to prepare transfer hardware\n"); + + if (master->auto_runtime_pm) + pm_runtime_put(master->dev.parent); + return; + } + } + + trace_spi_message_start(master->cur_msg); + + if (master->prepare_message) { + ret = master->prepare_message(master, master->cur_msg); + if (ret) { + dev_err(&master->dev, + "failed to prepare message: %d\n", ret); + master->cur_msg->status = ret; + spi_finalize_current_message(master); + return; + } + master->cur_msg_prepared = true; + } + + ret = spi_map_msg(master, master->cur_msg); + if (ret) { + master->cur_msg->status = ret; + spi_finalize_current_message(master); + return; + } + + ret = master->transfer_one_message(master, master->cur_msg); + if (ret) { + dev_err(&master->dev, + "failed to transfer one message from queue\n"); + return; + } +} + +/** + * spi_pump_messages - kthread work function which processes spi message queue + * @work: pointer to kthread work struct contained in the master struct + */ +static void spi_pump_messages(struct kthread_work *work) +{ + struct spi_master *master = + container_of(work, struct spi_master, pump_messages); + + __spi_pump_messages(master, true); +} + +static int spi_init_queue(struct spi_master *master) +{ + struct sched_param param = { .sched_priority = MAX_RT_PRIO - 1 }; + + master->running = false; + master->busy = false; + + init_kthread_worker(&master->kworker); + master->kworker_task = kthread_run(kthread_worker_fn, + &master->kworker, "%s", + dev_name(&master->dev)); + if (IS_ERR(master->kworker_task)) { + dev_err(&master->dev, "failed to create message pump task\n"); + return PTR_ERR(master->kworker_task); + } + init_kthread_work(&master->pump_messages, spi_pump_messages); + + /* + * Master config will indicate if this controller should run the + * message pump with high (realtime) priority to reduce the transfer + * latency on the bus by minimising the delay between a transfer + * request and the scheduling of the message pump thread. Without this + * setting the message pump thread will remain at default priority. + */ + if (master->rt) { + dev_info(&master->dev, + "will run message pump with realtime priority\n"); + sched_setscheduler(master->kworker_task, SCHED_FIFO, ¶m); + } + + return 0; +} + +/** + * spi_get_next_queued_message() - called by driver to check for queued + * messages + * @master: the master to check for queued messages + * + * If there are more messages in the queue, the next message is returned from + * this call. + */ +struct spi_message *spi_get_next_queued_message(struct spi_master *master) +{ + struct spi_message *next; + unsigned long flags; + + /* get a pointer to the next message, if any */ + spin_lock_irqsave(&master->queue_lock, flags); + next = list_first_entry_or_null(&master->queue, struct spi_message, + queue); + spin_unlock_irqrestore(&master->queue_lock, flags); + + return next; +} +EXPORT_SYMBOL_GPL(spi_get_next_queued_message); + +/** + * spi_finalize_current_message() - the current message is complete + * @master: the master to return the message to + * + * Called by the driver to notify the core that the message in the front of the + * queue is complete and can be removed from the queue. + */ +void spi_finalize_current_message(struct spi_master *master) +{ + struct spi_message *mesg; + unsigned long flags; + int ret; + + spin_lock_irqsave(&master->queue_lock, flags); + mesg = master->cur_msg; + spin_unlock_irqrestore(&master->queue_lock, flags); + + spi_unmap_msg(master, mesg); + + if (master->cur_msg_prepared && master->unprepare_message) { + ret = master->unprepare_message(master, mesg); + if (ret) { + dev_err(&master->dev, + "failed to unprepare message: %d\n", ret); + } + } + + spin_lock_irqsave(&master->queue_lock, flags); + master->cur_msg = NULL; + master->cur_msg_prepared = false; + queue_kthread_work(&master->kworker, &master->pump_messages); + spin_unlock_irqrestore(&master->queue_lock, flags); + + trace_spi_message_done(mesg); + + mesg->state = NULL; + if (mesg->complete) + mesg->complete(mesg->context); +} +EXPORT_SYMBOL_GPL(spi_finalize_current_message); + +static int spi_start_queue(struct spi_master *master) +{ + unsigned long flags; + + spin_lock_irqsave(&master->queue_lock, flags); + + if (master->running || master->busy) { + spin_unlock_irqrestore(&master->queue_lock, flags); + return -EBUSY; + } + + master->running = true; + master->cur_msg = NULL; + spin_unlock_irqrestore(&master->queue_lock, flags); + + queue_kthread_work(&master->kworker, &master->pump_messages); + + return 0; +} + +static int spi_stop_queue(struct spi_master *master) +{ + unsigned long flags; + unsigned limit = 500; + int ret = 0; + + spin_lock_irqsave(&master->queue_lock, flags); + + /* + * This is a bit lame, but is optimized for the common execution path. + * A wait_queue on the master->busy could be used, but then the common + * execution path (pump_messages) would be required to call wake_up or + * friends on every SPI message. Do this instead. + */ + while ((!list_empty(&master->queue) || master->busy) && limit--) { + spin_unlock_irqrestore(&master->queue_lock, flags); + usleep_range(10000, 11000); + spin_lock_irqsave(&master->queue_lock, flags); + } + + if (!list_empty(&master->queue) || master->busy) + ret = -EBUSY; + else + master->running = false; + + spin_unlock_irqrestore(&master->queue_lock, flags); + + if (ret) { + dev_warn(&master->dev, + "could not stop message queue\n"); + return ret; + } + return ret; +} + +static int spi_destroy_queue(struct spi_master *master) +{ + int ret; + + ret = spi_stop_queue(master); + + /* + * flush_kthread_worker will block until all work is done. + * If the reason that stop_queue timed out is that the work will never + * finish, then it does no good to call flush/stop thread, so + * return anyway. + */ + if (ret) { + dev_err(&master->dev, "problem destroying queue\n"); + return ret; + } + + flush_kthread_worker(&master->kworker); + kthread_stop(master->kworker_task); + + return 0; +} + +static int __spi_queued_transfer(struct spi_device *spi, + struct spi_message *msg, + bool need_pump) +{ + struct spi_master *master = spi->master; + unsigned long flags; + + spin_lock_irqsave(&master->queue_lock, flags); + + if (!master->running) { + spin_unlock_irqrestore(&master->queue_lock, flags); + return -ESHUTDOWN; + } + msg->actual_length = 0; + msg->status = -EINPROGRESS; + + list_add_tail(&msg->queue, &master->queue); + if (!master->busy && need_pump) + queue_kthread_work(&master->kworker, &master->pump_messages); + + spin_unlock_irqrestore(&master->queue_lock, flags); + return 0; +} + +/** + * spi_queued_transfer - transfer function for queued transfers + * @spi: spi device which is requesting transfer + * @msg: spi message which is to handled is queued to driver queue + */ +static int spi_queued_transfer(struct spi_device *spi, struct spi_message *msg) +{ + return __spi_queued_transfer(spi, msg, true); +} + +static int spi_master_initialize_queue(struct spi_master *master) +{ + int ret; + + master->transfer = spi_queued_transfer; + if (!master->transfer_one_message) + master->transfer_one_message = spi_transfer_one_message; + + /* Initialize and start queue */ + ret = spi_init_queue(master); + if (ret) { + dev_err(&master->dev, "problem initializing queue\n"); + goto err_init_queue; + } + master->queued = true; + ret = spi_start_queue(master); + if (ret) { + dev_err(&master->dev, "problem starting queue\n"); + goto err_start_queue; + } + + return 0; + +err_start_queue: + spi_destroy_queue(master); +err_init_queue: + return ret; +} + +/*-------------------------------------------------------------------------*/ + +#if defined(CONFIG_OF) +static struct spi_device * +of_register_spi_device(struct spi_master *master, struct device_node *nc) +{ + struct spi_device *spi; + int rc; + u32 value; + + /* Alloc an spi_device */ + spi = spi_alloc_device(master); + if (!spi) { + dev_err(&master->dev, "spi_device alloc error for %s\n", + nc->full_name); + rc = -ENOMEM; + goto err_out; + } + + /* Select device driver */ + rc = of_modalias_node(nc, spi->modalias, + sizeof(spi->modalias)); + if (rc < 0) { + dev_err(&master->dev, "cannot find modalias for %s\n", + nc->full_name); + goto err_out; + } + + /* Device address */ + rc = of_property_read_u32(nc, "reg", &value); + if (rc) { + dev_err(&master->dev, "%s has no valid 'reg' property (%d)\n", + nc->full_name, rc); + goto err_out; + } + spi->chip_select = value; + + /* Mode (clock phase/polarity/etc.) */ + if (of_find_property(nc, "spi-cpha", NULL)) + spi->mode |= SPI_CPHA; + if (of_find_property(nc, "spi-cpol", NULL)) + spi->mode |= SPI_CPOL; + if (of_find_property(nc, "spi-cs-high", NULL)) + spi->mode |= SPI_CS_HIGH; + if (of_find_property(nc, "spi-3wire", NULL)) + spi->mode |= SPI_3WIRE; + if (of_find_property(nc, "spi-lsb-first", NULL)) + spi->mode |= SPI_LSB_FIRST; + + /* Device DUAL/QUAD mode */ + if (!of_property_read_u32(nc, "spi-tx-bus-width", &value)) { + switch (value) { + case 1: + break; + case 2: + spi->mode |= SPI_TX_DUAL; + break; + case 4: + spi->mode |= SPI_TX_QUAD; + break; + default: + dev_warn(&master->dev, + "spi-tx-bus-width %d not supported\n", + value); + break; + } + } + + if (!of_property_read_u32(nc, "spi-rx-bus-width", &value)) { + switch (value) { + case 1: + break; + case 2: + spi->mode |= SPI_RX_DUAL; + break; + case 4: + spi->mode |= SPI_RX_QUAD; + break; + default: + dev_warn(&master->dev, + "spi-rx-bus-width %d not supported\n", + value); + break; + } + } + + /* Device speed */ + rc = of_property_read_u32(nc, "spi-max-frequency", &value); + if (rc) { + dev_err(&master->dev, "%s has no valid 'spi-max-frequency' property (%d)\n", + nc->full_name, rc); + goto err_out; + } + spi->max_speed_hz = value; + + /* IRQ */ + spi->irq = irq_of_parse_and_map(nc, 0); + + /* Store a pointer to the node in the device structure */ + of_node_get(nc); + spi->dev.of_node = nc; + + /* Register the new device */ + rc = spi_add_device(spi); + if (rc) { + dev_err(&master->dev, "spi_device register error %s\n", + nc->full_name); + goto err_out; + } + + return spi; + +err_out: + spi_dev_put(spi); + return ERR_PTR(rc); +} + +/** + * of_register_spi_devices() - Register child devices onto the SPI bus + * @master: Pointer to spi_master device + * + * Registers an spi_device for each child node of master node which has a 'reg' + * property. + */ +static void of_register_spi_devices(struct spi_master *master) +{ + struct spi_device *spi; + struct device_node *nc; + + if (!master->dev.of_node) + return; + + for_each_available_child_of_node(master->dev.of_node, nc) { + spi = of_register_spi_device(master, nc); + if (IS_ERR(spi)) + dev_warn(&master->dev, "Failed to create SPI device for %s\n", + nc->full_name); + } +} +#else +static void of_register_spi_devices(struct spi_master *master) { } +#endif + +#ifdef CONFIG_ACPI +static int acpi_spi_add_resource(struct acpi_resource *ares, void *data) +{ + struct spi_device *spi = data; + + if (ares->type == ACPI_RESOURCE_TYPE_SERIAL_BUS) { + struct acpi_resource_spi_serialbus *sb; + + sb = &ares->data.spi_serial_bus; + if (sb->type == ACPI_RESOURCE_SERIAL_TYPE_SPI) { + spi->chip_select = sb->device_selection; + spi->max_speed_hz = sb->connection_speed; + + if (sb->clock_phase == ACPI_SPI_SECOND_PHASE) + spi->mode |= SPI_CPHA; + if (sb->clock_polarity == ACPI_SPI_START_HIGH) + spi->mode |= SPI_CPOL; + if (sb->device_polarity == ACPI_SPI_ACTIVE_HIGH) + spi->mode |= SPI_CS_HIGH; + } + } else if (spi->irq < 0) { + struct resource r; + + if (acpi_dev_resource_interrupt(ares, 0, &r)) + spi->irq = r.start; + } + + /* Always tell the ACPI core to skip this resource */ + return 1; +} + +static acpi_status acpi_spi_add_device(acpi_handle handle, u32 level, + void *data, void **return_value) +{ + struct spi_master *master = data; + struct list_head resource_list; + struct acpi_device *adev; + struct spi_device *spi; + int ret; + + if (acpi_bus_get_device(handle, &adev)) + return AE_OK; + if (acpi_bus_get_status(adev) || !adev->status.present) + return AE_OK; + + spi = spi_alloc_device(master); + if (!spi) { + dev_err(&master->dev, "failed to allocate SPI device for %s\n", + dev_name(&adev->dev)); + return AE_NO_MEMORY; + } + + ACPI_COMPANION_SET(&spi->dev, adev); + spi->irq = -1; + + INIT_LIST_HEAD(&resource_list); + ret = acpi_dev_get_resources(adev, &resource_list, + acpi_spi_add_resource, spi); + acpi_dev_free_resource_list(&resource_list); + + if (ret < 0 || !spi->max_speed_hz) { + spi_dev_put(spi); + return AE_OK; + } + + adev->power.flags.ignore_parent = true; + strlcpy(spi->modalias, acpi_device_hid(adev), sizeof(spi->modalias)); + if (spi_add_device(spi)) { + adev->power.flags.ignore_parent = false; + dev_err(&master->dev, "failed to add SPI device %s from ACPI\n", + dev_name(&adev->dev)); + spi_dev_put(spi); + } + + return AE_OK; +} + +static void acpi_register_spi_devices(struct spi_master *master) +{ + acpi_status status; + acpi_handle handle; + + handle = ACPI_HANDLE(master->dev.parent); + if (!handle) + return; + + status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1, + acpi_spi_add_device, NULL, + master, NULL); + if (ACPI_FAILURE(status)) + dev_warn(&master->dev, "failed to enumerate SPI slaves\n"); +} +#else +static inline void acpi_register_spi_devices(struct spi_master *master) {} +#endif /* CONFIG_ACPI */ + +static void spi_master_release(struct device *dev) +{ + struct spi_master *master; + + master = container_of(dev, struct spi_master, dev); + kfree(master); +} + +static struct class spi_master_class = { + .name = "spi_master", + .owner = THIS_MODULE, + .dev_release = spi_master_release, +}; + + + +/** + * spi_alloc_master - allocate SPI master controller + * @dev: the controller, possibly using the platform_bus + * @size: how much zeroed driver-private data to allocate; the pointer to this + * memory is in the driver_data field of the returned device, + * accessible with spi_master_get_devdata(). + * Context: can sleep + * + * This call is used only by SPI master controller drivers, which are the + * only ones directly touching chip registers. It's how they allocate + * an spi_master structure, prior to calling spi_register_master(). + * + * This must be called from context that can sleep. It returns the SPI + * master structure on success, else NULL. + * + * The caller is responsible for assigning the bus number and initializing + * the master's methods before calling spi_register_master(); and (after errors + * adding the device) calling spi_master_put() and kfree() to prevent a memory + * leak. + */ +struct spi_master *spi_alloc_master(struct device *dev, unsigned size) +{ + struct spi_master *master; + + if (!dev) + return NULL; + + master = kzalloc(size + sizeof(*master), GFP_KERNEL); + if (!master) + return NULL; + + device_initialize(&master->dev); + master->bus_num = -1; + master->num_chipselect = 1; + master->dev.class = &spi_master_class; + master->dev.parent = get_device(dev); + spi_master_set_devdata(master, &master[1]); + + return master; +} +EXPORT_SYMBOL_GPL(spi_alloc_master); + +#ifdef CONFIG_OF +static int of_spi_register_master(struct spi_master *master) +{ + int nb, i, *cs; + struct device_node *np = master->dev.of_node; + + if (!np) + return 0; + + nb = of_gpio_named_count(np, "cs-gpios"); + master->num_chipselect = max_t(int, nb, master->num_chipselect); + + /* Return error only for an incorrectly formed cs-gpios property */ + if (nb == 0 || nb == -ENOENT) + return 0; + else if (nb < 0) + return nb; + + cs = devm_kzalloc(&master->dev, + sizeof(int) * master->num_chipselect, + GFP_KERNEL); + master->cs_gpios = cs; + + if (!master->cs_gpios) + return -ENOMEM; + + for (i = 0; i < master->num_chipselect; i++) + cs[i] = -ENOENT; + + for (i = 0; i < nb; i++) + cs[i] = of_get_named_gpio(np, "cs-gpios", i); + + return 0; +} +#else +static int of_spi_register_master(struct spi_master *master) +{ + return 0; +} +#endif + +/** + * spi_register_master - register SPI master controller + * @master: initialized master, originally from spi_alloc_master() + * Context: can sleep + * + * SPI master controllers connect to their drivers using some non-SPI bus, + * such as the platform bus. The final stage of probe() in that code + * includes calling spi_register_master() to hook up to this SPI bus glue. + * + * SPI controllers use board specific (often SOC specific) bus numbers, + * and board-specific addressing for SPI devices combines those numbers + * with chip select numbers. Since SPI does not directly support dynamic + * device identification, boards need configuration tables telling which + * chip is at which address. + * + * This must be called from context that can sleep. It returns zero on + * success, else a negative error code (dropping the master's refcount). + * After a successful return, the caller is responsible for calling + * spi_unregister_master(). + */ +int spi_register_master(struct spi_master *master) +{ + static atomic_t dyn_bus_id = ATOMIC_INIT((1<<15) - 1); + struct device *dev = master->dev.parent; + struct boardinfo *bi; + int status = -ENODEV; + int dynamic = 0; + + if (!dev) + return -ENODEV; + + status = of_spi_register_master(master); + if (status) + return status; + + /* even if it's just one always-selected device, there must + * be at least one chipselect + */ + if (master->num_chipselect == 0) + return -EINVAL; + + if ((master->bus_num < 0) && master->dev.of_node) + master->bus_num = of_alias_get_id(master->dev.of_node, "spi"); + + /* convention: dynamically assigned bus IDs count down from the max */ + if (master->bus_num < 0) { + /* FIXME switch to an IDR based scheme, something like + * I2C now uses, so we can't run out of "dynamic" IDs + */ + master->bus_num = atomic_dec_return(&dyn_bus_id); + dynamic = 1; + } + + INIT_LIST_HEAD(&master->queue); + spin_lock_init(&master->queue_lock); + spin_lock_init(&master->bus_lock_spinlock); + mutex_init(&master->bus_lock_mutex); + master->bus_lock_flag = 0; + init_completion(&master->xfer_completion); + if (!master->max_dma_len) + master->max_dma_len = INT_MAX; + + /* register the device, then userspace will see it. + * registration fails if the bus ID is in use. + */ + dev_set_name(&master->dev, "spi%u", master->bus_num); + status = device_add(&master->dev); + if (status < 0) + goto done; + dev_dbg(dev, "registered master %s%s\n", dev_name(&master->dev), + dynamic ? " (dynamic)" : ""); + + /* If we're using a queued driver, start the queue */ + if (master->transfer) + dev_info(dev, "master is unqueued, this is deprecated\n"); + else { + status = spi_master_initialize_queue(master); + if (status) { + device_del(&master->dev); + goto done; + } + } + + mutex_lock(&board_lock); + list_add_tail(&master->list, &spi_master_list); + list_for_each_entry(bi, &board_list, list) + spi_match_master_to_boardinfo(master, &bi->board_info); + mutex_unlock(&board_lock); + + /* Register devices from the device tree and ACPI */ + of_register_spi_devices(master); + acpi_register_spi_devices(master); +done: + return status; +} +EXPORT_SYMBOL_GPL(spi_register_master); + +static void devm_spi_unregister(struct device *dev, void *res) +{ + spi_unregister_master(*(struct spi_master **)res); +} + +/** + * dev_spi_register_master - register managed SPI master controller + * @dev: device managing SPI master + * @master: initialized master, originally from spi_alloc_master() + * Context: can sleep + * + * Register a SPI device as with spi_register_master() which will + * automatically be unregister + */ +int devm_spi_register_master(struct device *dev, struct spi_master *master) +{ + struct spi_master **ptr; + int ret; + + ptr = devres_alloc(devm_spi_unregister, sizeof(*ptr), GFP_KERNEL); + if (!ptr) + return -ENOMEM; + + ret = spi_register_master(master); + if (!ret) { + *ptr = master; + devres_add(dev, ptr); + } else { + devres_free(ptr); + } + + return ret; +} +EXPORT_SYMBOL_GPL(devm_spi_register_master); + +static int __unregister(struct device *dev, void *null) +{ + spi_unregister_device(to_spi_device(dev)); + return 0; +} + +/** + * spi_unregister_master - unregister SPI master controller + * @master: the master being unregistered + * Context: can sleep + * + * This call is used only by SPI master controller drivers, which are the + * only ones directly touching chip registers. + * + * This must be called from context that can sleep. + */ +void spi_unregister_master(struct spi_master *master) +{ + int dummy; + + if (master->queued) { + if (spi_destroy_queue(master)) + dev_err(&master->dev, "queue remove failed\n"); + } + + mutex_lock(&board_lock); + list_del(&master->list); + mutex_unlock(&board_lock); + + dummy = device_for_each_child(&master->dev, NULL, __unregister); + device_unregister(&master->dev); +} +EXPORT_SYMBOL_GPL(spi_unregister_master); + +int spi_master_suspend(struct spi_master *master) +{ + int ret; + + /* Basically no-ops for non-queued masters */ + if (!master->queued) + return 0; + + ret = spi_stop_queue(master); + if (ret) + dev_err(&master->dev, "queue stop failed\n"); + + return ret; +} +EXPORT_SYMBOL_GPL(spi_master_suspend); + +int spi_master_resume(struct spi_master *master) +{ + int ret; + + if (!master->queued) + return 0; + + ret = spi_start_queue(master); + if (ret) + dev_err(&master->dev, "queue restart failed\n"); + + return ret; +} +EXPORT_SYMBOL_GPL(spi_master_resume); + +static int __spi_master_match(struct device *dev, const void *data) +{ + struct spi_master *m; + const u16 *bus_num = data; + + m = container_of(dev, struct spi_master, dev); + return m->bus_num == *bus_num; +} + +/** + * spi_busnum_to_master - look up master associated with bus_num + * @bus_num: the master's bus number + * Context: can sleep + * + * This call may be used with devices that are registered after + * arch init time. It returns a refcounted pointer to the relevant + * spi_master (which the caller must release), or NULL if there is + * no such master registered. + */ +struct spi_master *spi_busnum_to_master(u16 bus_num) +{ + struct device *dev; + struct spi_master *master = NULL; + + dev = class_find_device(&spi_master_class, NULL, &bus_num, + __spi_master_match); + if (dev) + master = container_of(dev, struct spi_master, dev); + /* reference got in class_find_device */ + return master; +} +EXPORT_SYMBOL_GPL(spi_busnum_to_master); + + +/*-------------------------------------------------------------------------*/ + +/* Core methods for SPI master protocol drivers. Some of the + * other core methods are currently defined as inline functions. + */ + +/** + * spi_setup - setup SPI mode and clock rate + * @spi: the device whose settings are being modified + * Context: can sleep, and no requests are queued to the device + * + * SPI protocol drivers may need to update the transfer mode if the + * device doesn't work with its default. They may likewise need + * to update clock rates or word sizes from initial values. This function + * changes those settings, and must be called from a context that can sleep. + * Except for SPI_CS_HIGH, which takes effect immediately, the changes take + * effect the next time the device is selected and data is transferred to + * or from it. When this function returns, the spi device is deselected. + * + * Note that this call will fail if the protocol driver specifies an option + * that the underlying controller or its driver does not support. For + * example, not all hardware supports wire transfers using nine bit words, + * LSB-first wire encoding, or active-high chipselects. + */ +int spi_setup(struct spi_device *spi) +{ + unsigned bad_bits, ugly_bits; + int status = 0; + + /* check mode to prevent that DUAL and QUAD set at the same time + */ + if (((spi->mode & SPI_TX_DUAL) && (spi->mode & SPI_TX_QUAD)) || + ((spi->mode & SPI_RX_DUAL) && (spi->mode & SPI_RX_QUAD))) { + dev_err(&spi->dev, + "setup: can not select dual and quad at the same time\n"); + return -EINVAL; + } + /* if it is SPI_3WIRE mode, DUAL and QUAD should be forbidden + */ + if ((spi->mode & SPI_3WIRE) && (spi->mode & + (SPI_TX_DUAL | SPI_TX_QUAD | SPI_RX_DUAL | SPI_RX_QUAD))) + return -EINVAL; + /* help drivers fail *cleanly* when they need options + * that aren't supported with their current master + */ + bad_bits = spi->mode & ~spi->master->mode_bits; + ugly_bits = bad_bits & + (SPI_TX_DUAL | SPI_TX_QUAD | SPI_RX_DUAL | SPI_RX_QUAD); + if (ugly_bits) { + dev_warn(&spi->dev, + "setup: ignoring unsupported mode bits %x\n", + ugly_bits); + spi->mode &= ~ugly_bits; + bad_bits &= ~ugly_bits; + } + if (bad_bits) { + dev_err(&spi->dev, "setup: unsupported mode bits %x\n", + bad_bits); + return -EINVAL; + } + + if (!spi->bits_per_word) + spi->bits_per_word = 8; + + if (!spi->max_speed_hz) + spi->max_speed_hz = spi->master->max_speed_hz; + + spi_set_cs(spi, false); + + if (spi->master->setup) + status = spi->master->setup(spi); + + dev_dbg(&spi->dev, "setup mode %d, %s%s%s%s%u bits/w, %u Hz max --> %d\n", + (int) (spi->mode & (SPI_CPOL | SPI_CPHA)), + (spi->mode & SPI_CS_HIGH) ? "cs_high, " : "", + (spi->mode & SPI_LSB_FIRST) ? "lsb, " : "", + (spi->mode & SPI_3WIRE) ? "3wire, " : "", + (spi->mode & SPI_LOOP) ? "loopback, " : "", + spi->bits_per_word, spi->max_speed_hz, + status); + + return status; +} +EXPORT_SYMBOL_GPL(spi_setup); + +static int __spi_validate(struct spi_device *spi, struct spi_message *message) +{ + struct spi_master *master = spi->master; + struct spi_transfer *xfer; + int w_size; + + if (list_empty(&message->transfers)) + return -EINVAL; + + /* Half-duplex links include original MicroWire, and ones with + * only one data pin like SPI_3WIRE (switches direction) or where + * either MOSI or MISO is missing. They can also be caused by + * software limitations. + */ + if ((master->flags & SPI_MASTER_HALF_DUPLEX) + || (spi->mode & SPI_3WIRE)) { + unsigned flags = master->flags; + + list_for_each_entry(xfer, &message->transfers, transfer_list) { + if (xfer->rx_buf && xfer->tx_buf) + return -EINVAL; + if ((flags & SPI_MASTER_NO_TX) && xfer->tx_buf) + return -EINVAL; + if ((flags & SPI_MASTER_NO_RX) && xfer->rx_buf) + return -EINVAL; + } + } + + /** + * Set transfer bits_per_word and max speed as spi device default if + * it is not set for this transfer. + * Set transfer tx_nbits and rx_nbits as single transfer default + * (SPI_NBITS_SINGLE) if it is not set for this transfer. + */ + list_for_each_entry(xfer, &message->transfers, transfer_list) { + message->frame_length += xfer->len; + if (!xfer->bits_per_word) + xfer->bits_per_word = spi->bits_per_word; + + if (!xfer->speed_hz) + xfer->speed_hz = spi->max_speed_hz; + + if (master->max_speed_hz && + xfer->speed_hz > master->max_speed_hz) + xfer->speed_hz = master->max_speed_hz; + + if (master->bits_per_word_mask) { + /* Only 32 bits fit in the mask */ + if (xfer->bits_per_word > 32) + return -EINVAL; + if (!(master->bits_per_word_mask & + BIT(xfer->bits_per_word - 1))) + return -EINVAL; + } + + /* + * SPI transfer length should be multiple of SPI word size + * where SPI word size should be power-of-two multiple + */ + if (xfer->bits_per_word <= 8) + w_size = 1; + else if (xfer->bits_per_word <= 16) + w_size = 2; + else + w_size = 4; + + /* No partial transfers accepted */ + if (xfer->len % w_size) + return -EINVAL; + + if (xfer->speed_hz && master->min_speed_hz && + xfer->speed_hz < master->min_speed_hz) + return -EINVAL; + + if (xfer->tx_buf && !xfer->tx_nbits) + xfer->tx_nbits = SPI_NBITS_SINGLE; + if (xfer->rx_buf && !xfer->rx_nbits) + xfer->rx_nbits = SPI_NBITS_SINGLE; + /* check transfer tx/rx_nbits: + * 1. check the value matches one of single, dual and quad + * 2. check tx/rx_nbits match the mode in spi_device + */ + if (xfer->tx_buf) { + if (xfer->tx_nbits != SPI_NBITS_SINGLE && + xfer->tx_nbits != SPI_NBITS_DUAL && + xfer->tx_nbits != SPI_NBITS_QUAD) + return -EINVAL; + if ((xfer->tx_nbits == SPI_NBITS_DUAL) && + !(spi->mode & (SPI_TX_DUAL | SPI_TX_QUAD))) + return -EINVAL; + if ((xfer->tx_nbits == SPI_NBITS_QUAD) && + !(spi->mode & SPI_TX_QUAD)) + return -EINVAL; + } + /* check transfer rx_nbits */ + if (xfer->rx_buf) { + if (xfer->rx_nbits != SPI_NBITS_SINGLE && + xfer->rx_nbits != SPI_NBITS_DUAL && + xfer->rx_nbits != SPI_NBITS_QUAD) + return -EINVAL; + if ((xfer->rx_nbits == SPI_NBITS_DUAL) && + !(spi->mode & (SPI_RX_DUAL | SPI_RX_QUAD))) + return -EINVAL; + if ((xfer->rx_nbits == SPI_NBITS_QUAD) && + !(spi->mode & SPI_RX_QUAD)) + return -EINVAL; + } + } + + message->status = -EINPROGRESS; + + return 0; +} + +static int __spi_async(struct spi_device *spi, struct spi_message *message) +{ + struct spi_master *master = spi->master; + + message->spi = spi; + + trace_spi_message_submit(message); + + return master->transfer(spi, message); +} + +/** + * spi_async - asynchronous SPI transfer + * @spi: device with which data will be exchanged + * @message: describes the data transfers, including completion callback + * Context: any (irqs may be blocked, etc) + * + * This call may be used in_irq and other contexts which can't sleep, + * as well as from task contexts which can sleep. + * + * The completion callback is invoked in a context which can't sleep. + * Before that invocation, the value of message->status is undefined. + * When the callback is issued, message->status holds either zero (to + * indicate complete success) or a negative error code. After that + * callback returns, the driver which issued the transfer request may + * deallocate the associated memory; it's no longer in use by any SPI + * core or controller driver code. + * + * Note that although all messages to a spi_device are handled in + * FIFO order, messages may go to different devices in other orders. + * Some device might be higher priority, or have various "hard" access + * time requirements, for example. + * + * On detection of any fault during the transfer, processing of + * the entire message is aborted, and the device is deselected. + * Until returning from the associated message completion callback, + * no other spi_message queued to that device will be processed. + * (This rule applies equally to all the synchronous transfer calls, + * which are wrappers around this core asynchronous primitive.) + */ +int spi_async(struct spi_device *spi, struct spi_message *message) +{ + struct spi_master *master = spi->master; + int ret; + unsigned long flags; + + ret = __spi_validate(spi, message); + if (ret != 0) + return ret; + + spin_lock_irqsave(&master->bus_lock_spinlock, flags); + + if (master->bus_lock_flag) + ret = -EBUSY; + else + ret = __spi_async(spi, message); + + spin_unlock_irqrestore(&master->bus_lock_spinlock, flags); + + return ret; +} +EXPORT_SYMBOL_GPL(spi_async); + +/** + * spi_async_locked - version of spi_async with exclusive bus usage + * @spi: device with which data will be exchanged + * @message: describes the data transfers, including completion callback + * Context: any (irqs may be blocked, etc) + * + * This call may be used in_irq and other contexts which can't sleep, + * as well as from task contexts which can sleep. + * + * The completion callback is invoked in a context which can't sleep. + * Before that invocation, the value of message->status is undefined. + * When the callback is issued, message->status holds either zero (to + * indicate complete success) or a negative error code. After that + * callback returns, the driver which issued the transfer request may + * deallocate the associated memory; it's no longer in use by any SPI + * core or controller driver code. + * + * Note that although all messages to a spi_device are handled in + * FIFO order, messages may go to different devices in other orders. + * Some device might be higher priority, or have various "hard" access + * time requirements, for example. + * + * On detection of any fault during the transfer, processing of + * the entire message is aborted, and the device is deselected. + * Until returning from the associated message completion callback, + * no other spi_message queued to that device will be processed. + * (This rule applies equally to all the synchronous transfer calls, + * which are wrappers around this core asynchronous primitive.) + */ +int spi_async_locked(struct spi_device *spi, struct spi_message *message) +{ + struct spi_master *master = spi->master; + int ret; + unsigned long flags; + + ret = __spi_validate(spi, message); + if (ret != 0) + return ret; + + spin_lock_irqsave(&master->bus_lock_spinlock, flags); + + ret = __spi_async(spi, message); + + spin_unlock_irqrestore(&master->bus_lock_spinlock, flags); + + return ret; + +} +EXPORT_SYMBOL_GPL(spi_async_locked); + + +/*-------------------------------------------------------------------------*/ + +/* Utility methods for SPI master protocol drivers, layered on + * top of the core. Some other utility methods are defined as + * inline functions. + */ + +static void spi_complete(void *arg) +{ + complete(arg); +} + +static int __spi_sync(struct spi_device *spi, struct spi_message *message, + int bus_locked) +{ + DECLARE_COMPLETION_ONSTACK(done); + int status; + struct spi_master *master = spi->master; + unsigned long flags; + + status = __spi_validate(spi, message); + if (status != 0) + return status; + + message->complete = spi_complete; + message->context = &done; + message->spi = spi; + + if (!bus_locked) + mutex_lock(&master->bus_lock_mutex); + + /* If we're not using the legacy transfer method then we will + * try to transfer in the calling context so special case. + * This code would be less tricky if we could remove the + * support for driver implemented message queues. + */ + if (master->transfer == spi_queued_transfer) { + spin_lock_irqsave(&master->bus_lock_spinlock, flags); + + trace_spi_message_submit(message); + + status = __spi_queued_transfer(spi, message, false); + + spin_unlock_irqrestore(&master->bus_lock_spinlock, flags); + } else { + status = spi_async_locked(spi, message); + } + + if (!bus_locked) + mutex_unlock(&master->bus_lock_mutex); + + if (status == 0) { + /* Push out the messages in the calling context if we + * can. + */ + if (master->transfer == spi_queued_transfer) + __spi_pump_messages(master, false); + + wait_for_completion(&done); + status = message->status; + } + message->context = NULL; + return status; +} + +/** + * spi_sync - blocking/synchronous SPI data transfers + * @spi: device with which data will be exchanged + * @message: describes the data transfers + * Context: can sleep + * + * This call may only be used from a context that may sleep. The sleep + * is non-interruptible, and has no timeout. Low-overhead controller + * drivers may DMA directly into and out of the message buffers. + * + * Note that the SPI device's chip select is active during the message, + * and then is normally disabled between messages. Drivers for some + * frequently-used devices may want to minimize costs of selecting a chip, + * by leaving it selected in anticipation that the next message will go + * to the same chip. (That may increase power usage.) + * + * Also, the caller is guaranteeing that the memory associated with the + * message will not be freed before this call returns. + * + * It returns zero on success, else a negative error code. + */ +int spi_sync(struct spi_device *spi, struct spi_message *message) +{ + return __spi_sync(spi, message, 0); +} +EXPORT_SYMBOL_GPL(spi_sync); + +/** + * spi_sync_locked - version of spi_sync with exclusive bus usage + * @spi: device with which data will be exchanged + * @message: describes the data transfers + * Context: can sleep + * + * This call may only be used from a context that may sleep. The sleep + * is non-interruptible, and has no timeout. Low-overhead controller + * drivers may DMA directly into and out of the message buffers. + * + * This call should be used by drivers that require exclusive access to the + * SPI bus. It has to be preceded by a spi_bus_lock call. The SPI bus must + * be released by a spi_bus_unlock call when the exclusive access is over. + * + * It returns zero on success, else a negative error code. + */ +int spi_sync_locked(struct spi_device *spi, struct spi_message *message) +{ + return __spi_sync(spi, message, 1); +} +EXPORT_SYMBOL_GPL(spi_sync_locked); + +/** + * spi_bus_lock - obtain a lock for exclusive SPI bus usage + * @master: SPI bus master that should be locked for exclusive bus access + * Context: can sleep + * + * This call may only be used from a context that may sleep. The sleep + * is non-interruptible, and has no timeout. + * + * This call should be used by drivers that require exclusive access to the + * SPI bus. The SPI bus must be released by a spi_bus_unlock call when the + * exclusive access is over. Data transfer must be done by spi_sync_locked + * and spi_async_locked calls when the SPI bus lock is held. + * + * It returns zero on success, else a negative error code. + */ +int spi_bus_lock(struct spi_master *master) +{ + unsigned long flags; + + mutex_lock(&master->bus_lock_mutex); + + spin_lock_irqsave(&master->bus_lock_spinlock, flags); + master->bus_lock_flag = 1; + spin_unlock_irqrestore(&master->bus_lock_spinlock, flags); + + /* mutex remains locked until spi_bus_unlock is called */ + + return 0; +} +EXPORT_SYMBOL_GPL(spi_bus_lock); + +/** + * spi_bus_unlock - release the lock for exclusive SPI bus usage + * @master: SPI bus master that was locked for exclusive bus access + * Context: can sleep + * + * This call may only be used from a context that may sleep. The sleep + * is non-interruptible, and has no timeout. + * + * This call releases an SPI bus lock previously obtained by an spi_bus_lock + * call. + * + * It returns zero on success, else a negative error code. + */ +int spi_bus_unlock(struct spi_master *master) +{ + master->bus_lock_flag = 0; + + mutex_unlock(&master->bus_lock_mutex); + + return 0; +} +EXPORT_SYMBOL_GPL(spi_bus_unlock); + +/* portable code must never pass more than 32 bytes */ +#define SPI_BUFSIZ max(32, SMP_CACHE_BYTES) + +static u8 *buf; + +/** + * spi_write_then_read - SPI synchronous write followed by read + * @spi: device with which data will be exchanged + * @txbuf: data to be written (need not be dma-safe) + * @n_tx: size of txbuf, in bytes + * @rxbuf: buffer into which data will be read (need not be dma-safe) + * @n_rx: size of rxbuf, in bytes + * Context: can sleep + * + * This performs a half duplex MicroWire style transaction with the + * device, sending txbuf and then reading rxbuf. The return value + * is zero for success, else a negative errno status code. + * This call may only be used from a context that may sleep. + * + * Parameters to this routine are always copied using a small buffer; + * portable code should never use this for more than 32 bytes. + * Performance-sensitive or bulk transfer code should instead use + * spi_{async,sync}() calls with dma-safe buffers. + */ +int spi_write_then_read(struct spi_device *spi, + const void *txbuf, unsigned n_tx, + void *rxbuf, unsigned n_rx) +{ + static DEFINE_MUTEX(lock); + + int status; + struct spi_message message; + struct spi_transfer x[2]; + u8 *local_buf; + + /* Use preallocated DMA-safe buffer if we can. We can't avoid + * copying here, (as a pure convenience thing), but we can + * keep heap costs out of the hot path unless someone else is + * using the pre-allocated buffer or the transfer is too large. + */ + if ((n_tx + n_rx) > SPI_BUFSIZ || !mutex_trylock(&lock)) { + local_buf = kmalloc(max((unsigned)SPI_BUFSIZ, n_tx + n_rx), + GFP_KERNEL | GFP_DMA); + if (!local_buf) + return -ENOMEM; + } else { + local_buf = buf; + } + + spi_message_init(&message); + memset(x, 0, sizeof(x)); + if (n_tx) { + x[0].len = n_tx; + spi_message_add_tail(&x[0], &message); + } + if (n_rx) { + x[1].len = n_rx; + spi_message_add_tail(&x[1], &message); + } + + memcpy(local_buf, txbuf, n_tx); + x[0].tx_buf = local_buf; + x[1].rx_buf = local_buf + n_tx; + + /* do the i/o */ + status = spi_sync(spi, &message); + if (status == 0) + memcpy(rxbuf, x[1].rx_buf, n_rx); + + if (x[0].tx_buf == buf) + mutex_unlock(&lock); + else + kfree(local_buf); + + return status; +} +EXPORT_SYMBOL_GPL(spi_write_then_read); + +/*-------------------------------------------------------------------------*/ + +#if IS_ENABLED(CONFIG_OF_DYNAMIC) +static int __spi_of_device_match(struct device *dev, void *data) +{ + return dev->of_node == data; +} + +/* must call put_device() when done with returned spi_device device */ +static struct spi_device *of_find_spi_device_by_node(struct device_node *node) +{ + struct device *dev = bus_find_device(&spi_bus_type, NULL, node, + __spi_of_device_match); + return dev ? to_spi_device(dev) : NULL; +} + +static int __spi_of_master_match(struct device *dev, const void *data) +{ + return dev->of_node == data; +} + +/* the spi masters are not using spi_bus, so we find it with another way */ +static struct spi_master *of_find_spi_master_by_node(struct device_node *node) +{ + struct device *dev; + + dev = class_find_device(&spi_master_class, NULL, node, + __spi_of_master_match); + if (!dev) + return NULL; + + /* reference got in class_find_device */ + return container_of(dev, struct spi_master, dev); +} + +static int of_spi_notify(struct notifier_block *nb, unsigned long action, + void *arg) +{ + struct of_reconfig_data *rd = arg; + struct spi_master *master; + struct spi_device *spi; + + switch (of_reconfig_get_state_change(action, arg)) { + case OF_RECONFIG_CHANGE_ADD: + master = of_find_spi_master_by_node(rd->dn->parent); + if (master == NULL) + return NOTIFY_OK; /* not for us */ + + spi = of_register_spi_device(master, rd->dn); + put_device(&master->dev); + + if (IS_ERR(spi)) { + pr_err("%s: failed to create for '%s'\n", + __func__, rd->dn->full_name); + return notifier_from_errno(PTR_ERR(spi)); + } + break; + + case OF_RECONFIG_CHANGE_REMOVE: + /* find our device by node */ + spi = of_find_spi_device_by_node(rd->dn); + if (spi == NULL) + return NOTIFY_OK; /* no? not meant for us */ + + /* unregister takes one ref away */ + spi_unregister_device(spi); + + /* and put the reference of the find */ + put_device(&spi->dev); + break; + } + + return NOTIFY_OK; +} + +static struct notifier_block spi_of_notifier = { + .notifier_call = of_spi_notify, +}; +#else /* IS_ENABLED(CONFIG_OF_DYNAMIC) */ +extern struct notifier_block spi_of_notifier; +#endif /* IS_ENABLED(CONFIG_OF_DYNAMIC) */ + +static int __init spi_init(void) +{ + int status; + + buf = kmalloc(SPI_BUFSIZ, GFP_KERNEL); + if (!buf) { + status = -ENOMEM; + goto err0; + } + + status = bus_register(&spi_bus_type); + if (status < 0) + goto err1; + + status = class_register(&spi_master_class); + if (status < 0) + goto err2; + + if (IS_ENABLED(CONFIG_OF_DYNAMIC)) + WARN_ON(of_reconfig_notifier_register(&spi_of_notifier)); + + return 0; + +err2: + bus_unregister(&spi_bus_type); +err1: + kfree(buf); + buf = NULL; +err0: + return status; +} + +/* board_info is normally registered in arch_initcall(), + * but even essential drivers wait till later + * + * REVISIT only boardinfo really needs static linking. the rest (device and + * driver registration) _could_ be dynamically linked (modular) ... costs + * include needing to have boardinfo data structures be much more public. + */ +postcore_initcall(spi_init); + diff --git a/drivers/spi/spidev.c b/drivers/spi/spidev.c new file mode 100644 index 000000000..92c909eed --- /dev/null +++ b/drivers/spi/spidev.c @@ -0,0 +1,856 @@ +/* + * Simple synchronous userspace interface to SPI devices + * + * Copyright (C) 2006 SWAPP + * Andrea Paterniani <a.paterniani@swapp-eng.it> + * Copyright (C) 2007 David Brownell (simplification, cleanup) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/init.h> +#include <linux/module.h> +#include <linux/ioctl.h> +#include <linux/fs.h> +#include <linux/device.h> +#include <linux/err.h> +#include <linux/list.h> +#include <linux/errno.h> +#include <linux/mutex.h> +#include <linux/slab.h> +#include <linux/compat.h> +#include <linux/of.h> +#include <linux/of_device.h> + +#include <linux/spi/spi.h> +#include <linux/spi/spidev.h> + +#include <linux/uaccess.h> + + +/* + * This supports access to SPI devices using normal userspace I/O calls. + * Note that while traditional UNIX/POSIX I/O semantics are half duplex, + * and often mask message boundaries, full SPI support requires full duplex + * transfers. There are several kinds of internal message boundaries to + * handle chipselect management and other protocol options. + * + * SPI has a character major number assigned. We allocate minor numbers + * dynamically using a bitmask. You must use hotplug tools, such as udev + * (or mdev with busybox) to create and destroy the /dev/spidevB.C device + * nodes, since there is no fixed association of minor numbers with any + * particular SPI bus or device. + */ +#define SPIDEV_MAJOR 153 /* assigned */ +#define N_SPI_MINORS 32 /* ... up to 256 */ + +static DECLARE_BITMAP(minors, N_SPI_MINORS); + + +/* Bit masks for spi_device.mode management. Note that incorrect + * settings for some settings can cause *lots* of trouble for other + * devices on a shared bus: + * + * - CS_HIGH ... this device will be active when it shouldn't be + * - 3WIRE ... when active, it won't behave as it should + * - NO_CS ... there will be no explicit message boundaries; this + * is completely incompatible with the shared bus model + * - READY ... transfers may proceed when they shouldn't. + * + * REVISIT should changing those flags be privileged? + */ +#define SPI_MODE_MASK (SPI_CPHA | SPI_CPOL | SPI_CS_HIGH \ + | SPI_LSB_FIRST | SPI_3WIRE | SPI_LOOP \ + | SPI_NO_CS | SPI_READY | SPI_TX_DUAL \ + | SPI_TX_QUAD | SPI_RX_DUAL | SPI_RX_QUAD) + +struct spidev_data { + dev_t devt; + spinlock_t spi_lock; + struct spi_device *spi; + struct list_head device_entry; + + /* TX/RX buffers are NULL unless this device is open (users > 0) */ + struct mutex buf_lock; + unsigned users; + u8 *tx_buffer; + u8 *rx_buffer; + u32 speed_hz; +}; + +static LIST_HEAD(device_list); +static DEFINE_MUTEX(device_list_lock); + +static unsigned bufsiz = 4096; +module_param(bufsiz, uint, S_IRUGO); +MODULE_PARM_DESC(bufsiz, "data bytes in biggest supported SPI message"); + +/*-------------------------------------------------------------------------*/ + +/* + * We can't use the standard synchronous wrappers for file I/O; we + * need to protect against async removal of the underlying spi_device. + */ +static void spidev_complete(void *arg) +{ + complete(arg); +} + +static ssize_t +spidev_sync(struct spidev_data *spidev, struct spi_message *message) +{ + DECLARE_COMPLETION_ONSTACK(done); + int status; + + message->complete = spidev_complete; + message->context = &done; + + spin_lock_irq(&spidev->spi_lock); + if (spidev->spi == NULL) + status = -ESHUTDOWN; + else + status = spi_async(spidev->spi, message); + spin_unlock_irq(&spidev->spi_lock); + + if (status == 0) { + wait_for_completion(&done); + status = message->status; + if (status == 0) + status = message->actual_length; + } + return status; +} + +static inline ssize_t +spidev_sync_write(struct spidev_data *spidev, size_t len) +{ + struct spi_transfer t = { + .tx_buf = spidev->tx_buffer, + .len = len, + .speed_hz = spidev->speed_hz, + }; + struct spi_message m; + + spi_message_init(&m); + spi_message_add_tail(&t, &m); + return spidev_sync(spidev, &m); +} + +static inline ssize_t +spidev_sync_read(struct spidev_data *spidev, size_t len) +{ + struct spi_transfer t = { + .rx_buf = spidev->rx_buffer, + .len = len, + .speed_hz = spidev->speed_hz, + }; + struct spi_message m; + + spi_message_init(&m); + spi_message_add_tail(&t, &m); + return spidev_sync(spidev, &m); +} + +/*-------------------------------------------------------------------------*/ + +/* Read-only message with current device setup */ +static ssize_t +spidev_read(struct file *filp, char __user *buf, size_t count, loff_t *f_pos) +{ + struct spidev_data *spidev; + ssize_t status = 0; + + /* chipselect only toggles at start or end of operation */ + if (count > bufsiz) + return -EMSGSIZE; + + spidev = filp->private_data; + + mutex_lock(&spidev->buf_lock); + status = spidev_sync_read(spidev, count); + if (status > 0) { + unsigned long missing; + + missing = copy_to_user(buf, spidev->rx_buffer, status); + if (missing == status) + status = -EFAULT; + else + status = status - missing; + } + mutex_unlock(&spidev->buf_lock); + + return status; +} + +/* Write-only message with current device setup */ +static ssize_t +spidev_write(struct file *filp, const char __user *buf, + size_t count, loff_t *f_pos) +{ + struct spidev_data *spidev; + ssize_t status = 0; + unsigned long missing; + + /* chipselect only toggles at start or end of operation */ + if (count > bufsiz) + return -EMSGSIZE; + + spidev = filp->private_data; + + mutex_lock(&spidev->buf_lock); + missing = copy_from_user(spidev->tx_buffer, buf, count); + if (missing == 0) + status = spidev_sync_write(spidev, count); + else + status = -EFAULT; + mutex_unlock(&spidev->buf_lock); + + return status; +} + +static int spidev_message(struct spidev_data *spidev, + struct spi_ioc_transfer *u_xfers, unsigned n_xfers) +{ + struct spi_message msg; + struct spi_transfer *k_xfers; + struct spi_transfer *k_tmp; + struct spi_ioc_transfer *u_tmp; + unsigned n, total, tx_total, rx_total; + u8 *tx_buf, *rx_buf; + int status = -EFAULT; + + spi_message_init(&msg); + k_xfers = kcalloc(n_xfers, sizeof(*k_tmp), GFP_KERNEL); + if (k_xfers == NULL) + return -ENOMEM; + + /* Construct spi_message, copying any tx data to bounce buffer. + * We walk the array of user-provided transfers, using each one + * to initialize a kernel version of the same transfer. + */ + tx_buf = spidev->tx_buffer; + rx_buf = spidev->rx_buffer; + total = 0; + tx_total = 0; + rx_total = 0; + for (n = n_xfers, k_tmp = k_xfers, u_tmp = u_xfers; + n; + n--, k_tmp++, u_tmp++) { + k_tmp->len = u_tmp->len; + + total += k_tmp->len; + /* Since the function returns the total length of transfers + * on success, restrict the total to positive int values to + * avoid the return value looking like an error. Also check + * each transfer length to avoid arithmetic overflow. + */ + if (total > INT_MAX || k_tmp->len > INT_MAX) { + status = -EMSGSIZE; + goto done; + } + + if (u_tmp->rx_buf) { + /* this transfer needs space in RX bounce buffer */ + rx_total += k_tmp->len; + if (rx_total > bufsiz) { + status = -EMSGSIZE; + goto done; + } + k_tmp->rx_buf = rx_buf; + if (!access_ok(VERIFY_WRITE, (u8 __user *) + (uintptr_t) u_tmp->rx_buf, + u_tmp->len)) + goto done; + rx_buf += k_tmp->len; + } + if (u_tmp->tx_buf) { + /* this transfer needs space in TX bounce buffer */ + tx_total += k_tmp->len; + if (tx_total > bufsiz) { + status = -EMSGSIZE; + goto done; + } + k_tmp->tx_buf = tx_buf; + if (copy_from_user(tx_buf, (const u8 __user *) + (uintptr_t) u_tmp->tx_buf, + u_tmp->len)) + goto done; + tx_buf += k_tmp->len; + } + + k_tmp->cs_change = !!u_tmp->cs_change; + k_tmp->tx_nbits = u_tmp->tx_nbits; + k_tmp->rx_nbits = u_tmp->rx_nbits; + k_tmp->bits_per_word = u_tmp->bits_per_word; + k_tmp->delay_usecs = u_tmp->delay_usecs; + k_tmp->speed_hz = u_tmp->speed_hz; + if (!k_tmp->speed_hz) + k_tmp->speed_hz = spidev->speed_hz; +#ifdef VERBOSE + dev_dbg(&spidev->spi->dev, + " xfer len %zd %s%s%s%dbits %u usec %uHz\n", + u_tmp->len, + u_tmp->rx_buf ? "rx " : "", + u_tmp->tx_buf ? "tx " : "", + u_tmp->cs_change ? "cs " : "", + u_tmp->bits_per_word ? : spidev->spi->bits_per_word, + u_tmp->delay_usecs, + u_tmp->speed_hz ? : spidev->spi->max_speed_hz); +#endif + spi_message_add_tail(k_tmp, &msg); + } + + status = spidev_sync(spidev, &msg); + if (status < 0) + goto done; + + /* copy any rx data out of bounce buffer */ + rx_buf = spidev->rx_buffer; + for (n = n_xfers, u_tmp = u_xfers; n; n--, u_tmp++) { + if (u_tmp->rx_buf) { + if (__copy_to_user((u8 __user *) + (uintptr_t) u_tmp->rx_buf, rx_buf, + u_tmp->len)) { + status = -EFAULT; + goto done; + } + rx_buf += u_tmp->len; + } + } + status = total; + +done: + kfree(k_xfers); + return status; +} + +static struct spi_ioc_transfer * +spidev_get_ioc_message(unsigned int cmd, struct spi_ioc_transfer __user *u_ioc, + unsigned *n_ioc) +{ + struct spi_ioc_transfer *ioc; + u32 tmp; + + /* Check type, command number and direction */ + if (_IOC_TYPE(cmd) != SPI_IOC_MAGIC + || _IOC_NR(cmd) != _IOC_NR(SPI_IOC_MESSAGE(0)) + || _IOC_DIR(cmd) != _IOC_WRITE) + return ERR_PTR(-ENOTTY); + + tmp = _IOC_SIZE(cmd); + if ((tmp % sizeof(struct spi_ioc_transfer)) != 0) + return ERR_PTR(-EINVAL); + *n_ioc = tmp / sizeof(struct spi_ioc_transfer); + if (*n_ioc == 0) + return NULL; + + /* copy into scratch area */ + ioc = kmalloc(tmp, GFP_KERNEL); + if (!ioc) + return ERR_PTR(-ENOMEM); + if (__copy_from_user(ioc, u_ioc, tmp)) { + kfree(ioc); + return ERR_PTR(-EFAULT); + } + return ioc; +} + +static long +spidev_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) +{ + int err = 0; + int retval = 0; + struct spidev_data *spidev; + struct spi_device *spi; + u32 tmp; + unsigned n_ioc; + struct spi_ioc_transfer *ioc; + + /* Check type and command number */ + if (_IOC_TYPE(cmd) != SPI_IOC_MAGIC) + return -ENOTTY; + + /* Check access direction once here; don't repeat below. + * IOC_DIR is from the user perspective, while access_ok is + * from the kernel perspective; so they look reversed. + */ + if (_IOC_DIR(cmd) & _IOC_READ) + err = !access_ok(VERIFY_WRITE, + (void __user *)arg, _IOC_SIZE(cmd)); + if (err == 0 && _IOC_DIR(cmd) & _IOC_WRITE) + err = !access_ok(VERIFY_READ, + (void __user *)arg, _IOC_SIZE(cmd)); + if (err) + return -EFAULT; + + /* guard against device removal before, or while, + * we issue this ioctl. + */ + spidev = filp->private_data; + spin_lock_irq(&spidev->spi_lock); + spi = spi_dev_get(spidev->spi); + spin_unlock_irq(&spidev->spi_lock); + + if (spi == NULL) + return -ESHUTDOWN; + + /* use the buffer lock here for triple duty: + * - prevent I/O (from us) so calling spi_setup() is safe; + * - prevent concurrent SPI_IOC_WR_* from morphing + * data fields while SPI_IOC_RD_* reads them; + * - SPI_IOC_MESSAGE needs the buffer locked "normally". + */ + mutex_lock(&spidev->buf_lock); + + switch (cmd) { + /* read requests */ + case SPI_IOC_RD_MODE: + retval = __put_user(spi->mode & SPI_MODE_MASK, + (__u8 __user *)arg); + break; + case SPI_IOC_RD_MODE32: + retval = __put_user(spi->mode & SPI_MODE_MASK, + (__u32 __user *)arg); + break; + case SPI_IOC_RD_LSB_FIRST: + retval = __put_user((spi->mode & SPI_LSB_FIRST) ? 1 : 0, + (__u8 __user *)arg); + break; + case SPI_IOC_RD_BITS_PER_WORD: + retval = __put_user(spi->bits_per_word, (__u8 __user *)arg); + break; + case SPI_IOC_RD_MAX_SPEED_HZ: + retval = __put_user(spidev->speed_hz, (__u32 __user *)arg); + break; + + /* write requests */ + case SPI_IOC_WR_MODE: + case SPI_IOC_WR_MODE32: + if (cmd == SPI_IOC_WR_MODE) + retval = __get_user(tmp, (u8 __user *)arg); + else + retval = __get_user(tmp, (u32 __user *)arg); + if (retval == 0) { + u32 save = spi->mode; + + if (tmp & ~SPI_MODE_MASK) { + retval = -EINVAL; + break; + } + + tmp |= spi->mode & ~SPI_MODE_MASK; + spi->mode = (u16)tmp; + retval = spi_setup(spi); + if (retval < 0) + spi->mode = save; + else + dev_dbg(&spi->dev, "spi mode %x\n", tmp); + } + break; + case SPI_IOC_WR_LSB_FIRST: + retval = __get_user(tmp, (__u8 __user *)arg); + if (retval == 0) { + u32 save = spi->mode; + + if (tmp) + spi->mode |= SPI_LSB_FIRST; + else + spi->mode &= ~SPI_LSB_FIRST; + retval = spi_setup(spi); + if (retval < 0) + spi->mode = save; + else + dev_dbg(&spi->dev, "%csb first\n", + tmp ? 'l' : 'm'); + } + break; + case SPI_IOC_WR_BITS_PER_WORD: + retval = __get_user(tmp, (__u8 __user *)arg); + if (retval == 0) { + u8 save = spi->bits_per_word; + + spi->bits_per_word = tmp; + retval = spi_setup(spi); + if (retval < 0) + spi->bits_per_word = save; + else + dev_dbg(&spi->dev, "%d bits per word\n", tmp); + } + break; + case SPI_IOC_WR_MAX_SPEED_HZ: + retval = __get_user(tmp, (__u32 __user *)arg); + if (retval == 0) { + u32 save = spi->max_speed_hz; + + spi->max_speed_hz = tmp; + retval = spi_setup(spi); + if (retval >= 0) + spidev->speed_hz = tmp; + else + dev_dbg(&spi->dev, "%d Hz (max)\n", tmp); + spi->max_speed_hz = save; + } + break; + + default: + /* segmented and/or full-duplex I/O request */ + /* Check message and copy into scratch area */ + ioc = spidev_get_ioc_message(cmd, + (struct spi_ioc_transfer __user *)arg, &n_ioc); + if (IS_ERR(ioc)) { + retval = PTR_ERR(ioc); + break; + } + if (!ioc) + break; /* n_ioc is also 0 */ + + /* translate to spi_message, execute */ + retval = spidev_message(spidev, ioc, n_ioc); + kfree(ioc); + break; + } + + mutex_unlock(&spidev->buf_lock); + spi_dev_put(spi); + return retval; +} + +#ifdef CONFIG_COMPAT +static long +spidev_compat_ioc_message(struct file *filp, unsigned int cmd, + unsigned long arg) +{ + struct spi_ioc_transfer __user *u_ioc; + int retval = 0; + struct spidev_data *spidev; + struct spi_device *spi; + unsigned n_ioc, n; + struct spi_ioc_transfer *ioc; + + u_ioc = (struct spi_ioc_transfer __user *) compat_ptr(arg); + if (!access_ok(VERIFY_READ, u_ioc, _IOC_SIZE(cmd))) + return -EFAULT; + + /* guard against device removal before, or while, + * we issue this ioctl. + */ + spidev = filp->private_data; + spin_lock_irq(&spidev->spi_lock); + spi = spi_dev_get(spidev->spi); + spin_unlock_irq(&spidev->spi_lock); + + if (spi == NULL) + return -ESHUTDOWN; + + /* SPI_IOC_MESSAGE needs the buffer locked "normally" */ + mutex_lock(&spidev->buf_lock); + + /* Check message and copy into scratch area */ + ioc = spidev_get_ioc_message(cmd, u_ioc, &n_ioc); + if (IS_ERR(ioc)) { + retval = PTR_ERR(ioc); + goto done; + } + if (!ioc) + goto done; /* n_ioc is also 0 */ + + /* Convert buffer pointers */ + for (n = 0; n < n_ioc; n++) { + ioc[n].rx_buf = (uintptr_t) compat_ptr(ioc[n].rx_buf); + ioc[n].tx_buf = (uintptr_t) compat_ptr(ioc[n].tx_buf); + } + + /* translate to spi_message, execute */ + retval = spidev_message(spidev, ioc, n_ioc); + kfree(ioc); + +done: + mutex_unlock(&spidev->buf_lock); + spi_dev_put(spi); + return retval; +} + +static long +spidev_compat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) +{ + if (_IOC_TYPE(cmd) == SPI_IOC_MAGIC + && _IOC_NR(cmd) == _IOC_NR(SPI_IOC_MESSAGE(0)) + && _IOC_DIR(cmd) == _IOC_WRITE) + return spidev_compat_ioc_message(filp, cmd, arg); + + return spidev_ioctl(filp, cmd, (unsigned long)compat_ptr(arg)); +} +#else +#define spidev_compat_ioctl NULL +#endif /* CONFIG_COMPAT */ + +static int spidev_open(struct inode *inode, struct file *filp) +{ + struct spidev_data *spidev; + int status = -ENXIO; + + mutex_lock(&device_list_lock); + + list_for_each_entry(spidev, &device_list, device_entry) { + if (spidev->devt == inode->i_rdev) { + status = 0; + break; + } + } + + if (status) { + pr_debug("spidev: nothing for minor %d\n", iminor(inode)); + goto err_find_dev; + } + + if (!spidev->tx_buffer) { + spidev->tx_buffer = kmalloc(bufsiz, GFP_KERNEL); + if (!spidev->tx_buffer) { + dev_dbg(&spidev->spi->dev, "open/ENOMEM\n"); + status = -ENOMEM; + goto err_find_dev; + } + } + + if (!spidev->rx_buffer) { + spidev->rx_buffer = kmalloc(bufsiz, GFP_KERNEL); + if (!spidev->rx_buffer) { + dev_dbg(&spidev->spi->dev, "open/ENOMEM\n"); + status = -ENOMEM; + goto err_alloc_rx_buf; + } + } + + spidev->users++; + filp->private_data = spidev; + nonseekable_open(inode, filp); + + mutex_unlock(&device_list_lock); + return 0; + +err_alloc_rx_buf: + kfree(spidev->tx_buffer); + spidev->tx_buffer = NULL; +err_find_dev: + mutex_unlock(&device_list_lock); + return status; +} + +static int spidev_release(struct inode *inode, struct file *filp) +{ + struct spidev_data *spidev; + int status = 0; + + mutex_lock(&device_list_lock); + spidev = filp->private_data; + filp->private_data = NULL; + + /* last close? */ + spidev->users--; + if (!spidev->users) { + int dofree; + + kfree(spidev->tx_buffer); + spidev->tx_buffer = NULL; + + kfree(spidev->rx_buffer); + spidev->rx_buffer = NULL; + + spidev->speed_hz = spidev->spi->max_speed_hz; + + /* ... after we unbound from the underlying device? */ + spin_lock_irq(&spidev->spi_lock); + dofree = (spidev->spi == NULL); + spin_unlock_irq(&spidev->spi_lock); + + if (dofree) + kfree(spidev); + } + mutex_unlock(&device_list_lock); + + return status; +} + +static const struct file_operations spidev_fops = { + .owner = THIS_MODULE, + /* REVISIT switch to aio primitives, so that userspace + * gets more complete API coverage. It'll simplify things + * too, except for the locking. + */ + .write = spidev_write, + .read = spidev_read, + .unlocked_ioctl = spidev_ioctl, + .compat_ioctl = spidev_compat_ioctl, + .open = spidev_open, + .release = spidev_release, + .llseek = no_llseek, +}; + +/*-------------------------------------------------------------------------*/ + +/* The main reason to have this class is to make mdev/udev create the + * /dev/spidevB.C character device nodes exposing our userspace API. + * It also simplifies memory management. + */ + +static struct class *spidev_class; + +#ifdef CONFIG_OF +static const struct of_device_id spidev_dt_ids[] = { + { .compatible = "rohm,dh2228fv" }, + {}, +}; +MODULE_DEVICE_TABLE(of, spidev_dt_ids); +#endif + +/*-------------------------------------------------------------------------*/ + +static int spidev_probe(struct spi_device *spi) +{ + struct spidev_data *spidev; + int status; + unsigned long minor; + + /* + * spidev should never be referenced in DT without a specific + * compatbile string, it is a Linux implementation thing + * rather than a description of the hardware. + */ + if (spi->dev.of_node && !of_match_device(spidev_dt_ids, &spi->dev)) { + dev_err(&spi->dev, "buggy DT: spidev listed directly in DT\n"); + WARN_ON(spi->dev.of_node && + !of_match_device(spidev_dt_ids, &spi->dev)); + } + + /* Allocate driver data */ + spidev = kzalloc(sizeof(*spidev), GFP_KERNEL); + if (!spidev) + return -ENOMEM; + + /* Initialize the driver data */ + spidev->spi = spi; + spin_lock_init(&spidev->spi_lock); + mutex_init(&spidev->buf_lock); + + INIT_LIST_HEAD(&spidev->device_entry); + + /* If we can allocate a minor number, hook up this device. + * Reusing minors is fine so long as udev or mdev is working. + */ + mutex_lock(&device_list_lock); + minor = find_first_zero_bit(minors, N_SPI_MINORS); + if (minor < N_SPI_MINORS) { + struct device *dev; + + spidev->devt = MKDEV(SPIDEV_MAJOR, minor); + dev = device_create(spidev_class, &spi->dev, spidev->devt, + spidev, "spidev%d.%d", + spi->master->bus_num, spi->chip_select); + status = PTR_ERR_OR_ZERO(dev); + } else { + dev_dbg(&spi->dev, "no minor number available!\n"); + status = -ENODEV; + } + if (status == 0) { + set_bit(minor, minors); + list_add(&spidev->device_entry, &device_list); + } + mutex_unlock(&device_list_lock); + + spidev->speed_hz = spi->max_speed_hz; + + if (status == 0) + spi_set_drvdata(spi, spidev); + else + kfree(spidev); + + return status; +} + +static int spidev_remove(struct spi_device *spi) +{ + struct spidev_data *spidev = spi_get_drvdata(spi); + + /* make sure ops on existing fds can abort cleanly */ + spin_lock_irq(&spidev->spi_lock); + spidev->spi = NULL; + spin_unlock_irq(&spidev->spi_lock); + + /* prevent new opens */ + mutex_lock(&device_list_lock); + list_del(&spidev->device_entry); + device_destroy(spidev_class, spidev->devt); + clear_bit(MINOR(spidev->devt), minors); + if (spidev->users == 0) + kfree(spidev); + mutex_unlock(&device_list_lock); + + return 0; +} + +static struct spi_driver spidev_spi_driver = { + .driver = { + .name = "spidev", + .owner = THIS_MODULE, + .of_match_table = of_match_ptr(spidev_dt_ids), + }, + .probe = spidev_probe, + .remove = spidev_remove, + + /* NOTE: suspend/resume methods are not necessary here. + * We don't do anything except pass the requests to/from + * the underlying controller. The refrigerator handles + * most issues; the controller driver handles the rest. + */ +}; + +/*-------------------------------------------------------------------------*/ + +static int __init spidev_init(void) +{ + int status; + + /* Claim our 256 reserved device numbers. Then register a class + * that will key udev/mdev to add/remove /dev nodes. Last, register + * the driver which manages those device numbers. + */ + BUILD_BUG_ON(N_SPI_MINORS > 256); + status = register_chrdev(SPIDEV_MAJOR, "spi", &spidev_fops); + if (status < 0) + return status; + + spidev_class = class_create(THIS_MODULE, "spidev"); + if (IS_ERR(spidev_class)) { + unregister_chrdev(SPIDEV_MAJOR, spidev_spi_driver.driver.name); + return PTR_ERR(spidev_class); + } + + status = spi_register_driver(&spidev_spi_driver); + if (status < 0) { + class_destroy(spidev_class); + unregister_chrdev(SPIDEV_MAJOR, spidev_spi_driver.driver.name); + } + return status; +} +module_init(spidev_init); + +static void __exit spidev_exit(void) +{ + spi_unregister_driver(&spidev_spi_driver); + class_destroy(spidev_class); + unregister_chrdev(SPIDEV_MAJOR, spidev_spi_driver.driver.name); +} +module_exit(spidev_exit); + +MODULE_AUTHOR("Andrea Paterniani, <a.paterniani@swapp-eng.it>"); +MODULE_DESCRIPTION("User mode SPI device interface"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("spi:spidev"); |