// SPDX-License-Identifier: GPL-2.0+ /** * 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 * Contributors: Aymen Bouattay * Peter Griffin * * Inspired by dwc3-omap.c and dwc3-exynos.c. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #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_ from usb3_top is selected * 2’b10 : pipew_ 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_DELAY_VBUSVALID | USB3_SEL_FORCE_OPMODE | USB3_FORCE_OPMODE(0x3) | USB3_SEL_FORCE_DPPULLDOWN2 | USB3_FORCE_DPPULLDOWN2 | USB3_SEL_FORCE_DMPULLDOWN2 | USB3_FORCE_DMPULLDOWN2); /* * USB3_PORT2_FORCE_VBUSVALID When '1' and when * USB3_PORT2_DEVICE_NOT_HOST = 1, forces VBUSVLDEXT2 input * of the pico PHY to 1. */ val |= USB3_DEVICE_NOT_HOST | USB3_FORCE_VBUSVALID; 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; 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 platform_device *child_pdev; 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); 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%pK, syscfg-reg offset 0x%x\n", dwc3_data->glue_base, dwc3_data->syscfg_reg_off); dwc3_data->rstc_pwrdn = devm_reset_control_get_exclusive(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_shared(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; } /* 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; } child_pdev = of_find_device_by_node(child); if (!child_pdev) { dev_err(dev, "failed to find dwc3 core device\n"); ret = -ENODEV; goto undo_softreset; } dwc3_data->dr_mode = usb_get_dr_mode(&child_pdev->dev); /* * 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 "); MODULE_DESCRIPTION("DesignWare USB3 STi Glue Layer"); MODULE_LICENSE("GPL v2");