diff options
Diffstat (limited to 'drivers/usb/dwc3/dwc3-st.c')
| -rw-r--r-- | drivers/usb/dwc3/dwc3-st.c | 367 |
1 files changed, 367 insertions, 0 deletions
diff --git a/drivers/usb/dwc3/dwc3-st.c b/drivers/usb/dwc3/dwc3-st.c new file mode 100644 index 000000000..4a1a543de --- /dev/null +++ b/drivers/usb/dwc3/dwc3-st.c @@ -0,0 +1,367 @@ +/** + * dwc3-st.c Support for dwc3 platform devices on ST Microelectronics platforms + * + * This is a small driver for the dwc3 to provide the glue logic + * to configure the controller. Tested on STi platforms. + * + * Copyright (C) 2014 Stmicroelectronics + * + * Author: Giuseppe Cavallaro <peppe.cavallaro@st.com> + * Contributors: Aymen Bouattay <aymen.bouattay@st.com> + * Peter Griffin <peter.griffin@linaro.org> + * + * 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. + * + * Inspired by dwc3-omap.c and dwc3-exynos.c. + */ + +#include <linux/delay.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/ioport.h> +#include <linux/kernel.h> +#include <linux/mfd/syscon.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_platform.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/regmap.h> +#include <linux/reset.h> +#include <linux/usb/of.h> + +#include "core.h" +#include "io.h" + +/* glue registers */ +#define CLKRST_CTRL 0x00 +#define AUX_CLK_EN BIT(0) +#define SW_PIPEW_RESET_N BIT(4) +#define EXT_CFG_RESET_N BIT(8) +/* + * 1'b0 : The host controller complies with the xHCI revision 0.96 + * 1'b1 : The host controller complies with the xHCI revision 1.0 + */ +#define XHCI_REVISION BIT(12) + +#define USB2_VBUS_MNGMNT_SEL1 0x2C +/* + * For all fields in USB2_VBUS_MNGMNT_SEL1 + * 2’b00 : Override value from Reg 0x30 is selected + * 2’b01 : utmiotg_<signal_name> from usb3_top is selected + * 2’b10 : pipew_<signal_name> from PIPEW instance is selected + * 2’b11 : value is 1'b0 + */ +#define USB2_VBUS_REG30 0x0 +#define USB2_VBUS_UTMIOTG 0x1 +#define USB2_VBUS_PIPEW 0x2 +#define USB2_VBUS_ZERO 0x3 + +#define SEL_OVERRIDE_VBUSVALID(n) (n << 0) +#define SEL_OVERRIDE_POWERPRESENT(n) (n << 4) +#define SEL_OVERRIDE_BVALID(n) (n << 8) + +/* Static DRD configuration */ +#define USB3_CONTROL_MASK 0xf77 + +#define USB3_DEVICE_NOT_HOST BIT(0) +#define USB3_FORCE_VBUSVALID BIT(1) +#define USB3_DELAY_VBUSVALID BIT(2) +#define USB3_SEL_FORCE_OPMODE BIT(4) +#define USB3_FORCE_OPMODE(n) (n << 5) +#define USB3_SEL_FORCE_DPPULLDOWN2 BIT(8) +#define USB3_FORCE_DPPULLDOWN2 BIT(9) +#define USB3_SEL_FORCE_DMPULLDOWN2 BIT(10) +#define USB3_FORCE_DMPULLDOWN2 BIT(11) + +/** + * struct st_dwc3 - dwc3-st driver private structure + * @dev: device pointer + * @glue_base: ioaddr for the glue registers + * @regmap: regmap pointer for getting syscfg + * @syscfg_reg_off: usb syscfg control offset + * @dr_mode: drd static host/device config + * @rstc_pwrdn: rest controller for powerdown signal + * @rstc_rst: reset controller for softreset signal + */ + +struct st_dwc3 { + struct device *dev; + void __iomem *glue_base; + struct regmap *regmap; + int syscfg_reg_off; + enum usb_dr_mode dr_mode; + struct reset_control *rstc_pwrdn; + struct reset_control *rstc_rst; +}; + +static inline u32 st_dwc3_readl(void __iomem *base, u32 offset) +{ + return readl_relaxed(base + offset); +} + +static inline void st_dwc3_writel(void __iomem *base, u32 offset, u32 value) +{ + writel_relaxed(value, base + offset); +} + +/** + * st_dwc3_drd_init: program the port + * @dwc3_data: driver private structure + * Description: this function is to program the port as either host or device + * according to the static configuration passed from devicetree. + * OTG and dual role are not yet supported! + */ +static int st_dwc3_drd_init(struct st_dwc3 *dwc3_data) +{ + u32 val; + int err; + + err = regmap_read(dwc3_data->regmap, dwc3_data->syscfg_reg_off, &val); + if (err) + return err; + + val &= USB3_CONTROL_MASK; + + switch (dwc3_data->dr_mode) { + case USB_DR_MODE_PERIPHERAL: + + val &= ~(USB3_FORCE_VBUSVALID | USB3_DELAY_VBUSVALID + | USB3_SEL_FORCE_OPMODE | USB3_FORCE_OPMODE(0x3) + | USB3_SEL_FORCE_DPPULLDOWN2 | USB3_FORCE_DPPULLDOWN2 + | USB3_SEL_FORCE_DMPULLDOWN2 | USB3_FORCE_DMPULLDOWN2); + + val |= USB3_DEVICE_NOT_HOST; + + dev_dbg(dwc3_data->dev, "Configuring as Device\n"); + break; + + case USB_DR_MODE_HOST: + + val &= ~(USB3_DEVICE_NOT_HOST | USB3_FORCE_VBUSVALID + | USB3_SEL_FORCE_OPMODE | USB3_FORCE_OPMODE(0x3) + | USB3_SEL_FORCE_DPPULLDOWN2 | USB3_FORCE_DPPULLDOWN2 + | USB3_SEL_FORCE_DMPULLDOWN2 | USB3_FORCE_DMPULLDOWN2); + + /* + * USB3_DELAY_VBUSVALID is ANDed with USB_C_VBUSVALID. Thus, + * when set to ‘0‘, it can delay the arrival of VBUSVALID + * information to VBUSVLDEXT2 input of the pico PHY. + * We don't want to do that so we set the bit to '1'. + */ + + val |= USB3_DELAY_VBUSVALID; + + dev_dbg(dwc3_data->dev, "Configuring as Host\n"); + break; + + default: + dev_err(dwc3_data->dev, "Unsupported mode of operation %d\n", + dwc3_data->dr_mode); + return -EINVAL; + } + + return regmap_write(dwc3_data->regmap, dwc3_data->syscfg_reg_off, val); +} + +/** + * st_dwc3_init: init the controller via glue logic + * @dwc3_data: driver private structure + */ +static void st_dwc3_init(struct st_dwc3 *dwc3_data) +{ + u32 reg = st_dwc3_readl(dwc3_data->glue_base, CLKRST_CTRL); + + reg |= AUX_CLK_EN | EXT_CFG_RESET_N | XHCI_REVISION; + reg &= ~SW_PIPEW_RESET_N; + st_dwc3_writel(dwc3_data->glue_base, CLKRST_CTRL, reg); + + /* configure mux for vbus, powerpresent and bvalid signals */ + reg = st_dwc3_readl(dwc3_data->glue_base, USB2_VBUS_MNGMNT_SEL1); + + reg |= SEL_OVERRIDE_VBUSVALID(USB2_VBUS_UTMIOTG) | + SEL_OVERRIDE_POWERPRESENT(USB2_VBUS_UTMIOTG) | + SEL_OVERRIDE_BVALID(USB2_VBUS_UTMIOTG); + + st_dwc3_writel(dwc3_data->glue_base, USB2_VBUS_MNGMNT_SEL1, reg); + + reg = st_dwc3_readl(dwc3_data->glue_base, CLKRST_CTRL); + reg |= SW_PIPEW_RESET_N; + st_dwc3_writel(dwc3_data->glue_base, CLKRST_CTRL, reg); +} + +static int st_dwc3_probe(struct platform_device *pdev) +{ + struct st_dwc3 *dwc3_data; + struct resource *res; + struct device *dev = &pdev->dev; + struct device_node *node = dev->of_node, *child; + struct regmap *regmap; + int ret; + + dwc3_data = devm_kzalloc(dev, sizeof(*dwc3_data), GFP_KERNEL); + if (!dwc3_data) + return -ENOMEM; + + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "reg-glue"); + dwc3_data->glue_base = devm_ioremap_resource(dev, res); + if (IS_ERR(dwc3_data->glue_base)) + return PTR_ERR(dwc3_data->glue_base); + + regmap = syscon_regmap_lookup_by_phandle(node, "st,syscfg"); + if (IS_ERR(regmap)) + return PTR_ERR(regmap); + + dma_set_coherent_mask(dev, dev->coherent_dma_mask); + dwc3_data->dev = dev; + dwc3_data->regmap = regmap; + + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "syscfg-reg"); + if (!res) { + ret = -ENXIO; + goto undo_platform_dev_alloc; + } + + dwc3_data->syscfg_reg_off = res->start; + + dev_vdbg(&pdev->dev, "glue-logic addr 0x%p, syscfg-reg offset 0x%x\n", + dwc3_data->glue_base, dwc3_data->syscfg_reg_off); + + dwc3_data->rstc_pwrdn = devm_reset_control_get(dev, "powerdown"); + if (IS_ERR(dwc3_data->rstc_pwrdn)) { + dev_err(&pdev->dev, "could not get power controller\n"); + ret = PTR_ERR(dwc3_data->rstc_pwrdn); + goto undo_platform_dev_alloc; + } + + /* Manage PowerDown */ + reset_control_deassert(dwc3_data->rstc_pwrdn); + + dwc3_data->rstc_rst = devm_reset_control_get(dev, "softreset"); + if (IS_ERR(dwc3_data->rstc_rst)) { + dev_err(&pdev->dev, "could not get reset controller\n"); + ret = PTR_ERR(dwc3_data->rstc_rst); + goto undo_powerdown; + } + + /* Manage SoftReset */ + reset_control_deassert(dwc3_data->rstc_rst); + + child = of_get_child_by_name(node, "dwc3"); + if (!child) { + dev_err(&pdev->dev, "failed to find dwc3 core node\n"); + ret = -ENODEV; + goto undo_softreset; + } + + dwc3_data->dr_mode = of_usb_get_dr_mode(child); + + /* Allocate and initialize the core */ + ret = of_platform_populate(node, NULL, NULL, dev); + if (ret) { + dev_err(dev, "failed to add dwc3 core\n"); + goto undo_softreset; + } + + /* + * Configure the USB port as device or host according to the static + * configuration passed from DT. + * DRD is the only mode currently supported so this will be enhanced + * as soon as OTG is available. + */ + ret = st_dwc3_drd_init(dwc3_data); + if (ret) { + dev_err(dev, "drd initialisation failed\n"); + goto undo_softreset; + } + + /* ST glue logic init */ + st_dwc3_init(dwc3_data); + + platform_set_drvdata(pdev, dwc3_data); + return 0; + +undo_softreset: + reset_control_assert(dwc3_data->rstc_rst); +undo_powerdown: + reset_control_assert(dwc3_data->rstc_pwrdn); +undo_platform_dev_alloc: + platform_device_put(pdev); + return ret; +} + +static int st_dwc3_remove(struct platform_device *pdev) +{ + struct st_dwc3 *dwc3_data = platform_get_drvdata(pdev); + + of_platform_depopulate(&pdev->dev); + + reset_control_assert(dwc3_data->rstc_pwrdn); + reset_control_assert(dwc3_data->rstc_rst); + + return 0; +} + +#ifdef CONFIG_PM_SLEEP +static int st_dwc3_suspend(struct device *dev) +{ + struct st_dwc3 *dwc3_data = dev_get_drvdata(dev); + + reset_control_assert(dwc3_data->rstc_pwrdn); + reset_control_assert(dwc3_data->rstc_rst); + + pinctrl_pm_select_sleep_state(dev); + + return 0; +} + +static int st_dwc3_resume(struct device *dev) +{ + struct st_dwc3 *dwc3_data = dev_get_drvdata(dev); + int ret; + + pinctrl_pm_select_default_state(dev); + + reset_control_deassert(dwc3_data->rstc_pwrdn); + reset_control_deassert(dwc3_data->rstc_rst); + + ret = st_dwc3_drd_init(dwc3_data); + if (ret) { + dev_err(dev, "drd initialisation failed\n"); + return ret; + } + + /* ST glue logic init */ + st_dwc3_init(dwc3_data); + + return 0; +} +#endif /* CONFIG_PM_SLEEP */ + +static SIMPLE_DEV_PM_OPS(st_dwc3_dev_pm_ops, st_dwc3_suspend, st_dwc3_resume); + +static const struct of_device_id st_dwc3_match[] = { + { .compatible = "st,stih407-dwc3" }, + { /* sentinel */ }, +}; + +MODULE_DEVICE_TABLE(of, st_dwc3_match); + +static struct platform_driver st_dwc3_driver = { + .probe = st_dwc3_probe, + .remove = st_dwc3_remove, + .driver = { + .name = "usb-st-dwc3", + .of_match_table = st_dwc3_match, + .pm = &st_dwc3_dev_pm_ops, + }, +}; + +module_platform_driver(st_dwc3_driver); + +MODULE_AUTHOR("Giuseppe Cavallaro <peppe.cavallaro@st.com>"); +MODULE_DESCRIPTION("DesignWare USB3 STi Glue Layer"); +MODULE_LICENSE("GPL v2"); |