diff options
Diffstat (limited to 'drivers/spi/spi-rspi.c')
| -rw-r--r-- | drivers/spi/spi-rspi.c | 1326 |
1 files changed, 1326 insertions, 0 deletions
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"); |