Initial import

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");