drivers: usb: dwc3: Add AM62 USB wrapper driver
authorAswath Govindraju <a-govindraju@ti.com>
Thu, 14 Apr 2022 10:32:09 +0000 (16:02 +0530)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 21 Apr 2022 16:31:56 +0000 (18:31 +0200)
In AM62 SoC, the Designware Core USB3 IP is progammed to operate in USB2.0
only mode. Add driver for AM62 USB DWC3 Wrapper.

Signed-off-by: Aswath Govindraju <a-govindraju@ti.com>
Link: https://lore.kernel.org/r/20220414103211.16202-3-a-govindraju@ti.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/usb/dwc3/Kconfig
drivers/usb/dwc3/Makefile
drivers/usb/dwc3/dwc3-am62.c [new file with mode: 0644]

index c483f28..cd9a734 100644 (file)
@@ -159,4 +159,13 @@ config USB_DWC3_XILINX
          This driver handles both ZynqMP and Versal SoC operations.
          Say 'Y' or 'M' if you have one such device.
 
+config USB_DWC3_AM62
+       tristate "Texas Instruments AM62 Platforms"
+       depends on ARCH_K3 || COMPILE_TEST
+       default USB_DWC3
+       help
+         Support TI's AM62 platforms with DesignWare Core USB3 IP.
+         The Designware Core USB3 IP is progammed to operate in
+         in USB 2.0 mode only.
+         Say 'Y' or 'M' here if you have one such device
 endif
index 2d499de..9f66bd8 100644 (file)
@@ -42,6 +42,7 @@ endif
 # and allyesconfig builds.
 ##
 
+obj-$(CONFIG_USB_DWC3_AM62)            += dwc3-am62.o
 obj-$(CONFIG_USB_DWC3_OMAP)            += dwc3-omap.o
 obj-$(CONFIG_USB_DWC3_EXYNOS)          += dwc3-exynos.o
 obj-$(CONFIG_USB_DWC3_PCI)             += dwc3-pci.o
diff --git a/drivers/usb/dwc3/dwc3-am62.c b/drivers/usb/dwc3/dwc3-am62.c
new file mode 100644 (file)
index 0000000..fea7aca
--- /dev/null
@@ -0,0 +1,332 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * dwc3-am62.c - TI specific Glue layer for AM62 DWC3 USB Controller
+ *
+ * Copyright (C) 2022 Texas Instruments Incorporated - https://www.ti.com
+ */
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/mfd/syscon.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/clk.h>
+#include <linux/regmap.h>
+#include <linux/pinctrl/consumer.h>
+
+/* USB WRAPPER register offsets */
+#define USBSS_PID                      0x0
+#define USBSS_OVERCURRENT_CTRL         0x4
+#define USBSS_PHY_CONFIG               0x8
+#define USBSS_PHY_TEST                 0xc
+#define USBSS_CORE_STAT                        0x14
+#define USBSS_HOST_VBUS_CTRL           0x18
+#define USBSS_MODE_CONTROL             0x1c
+#define USBSS_WAKEUP_CONFIG            0x30
+#define USBSS_WAKEUP_STAT              0x34
+#define USBSS_OVERRIDE_CONFIG          0x38
+#define USBSS_IRQ_MISC_STATUS_RAW      0x430
+#define USBSS_IRQ_MISC_STATUS          0x434
+#define USBSS_IRQ_MISC_ENABLE_SET      0x438
+#define USBSS_IRQ_MISC_ENABLE_CLR      0x43c
+#define USBSS_IRQ_MISC_EOI             0x440
+#define USBSS_INTR_TEST                        0x490
+#define USBSS_VBUS_FILTER              0x614
+#define USBSS_VBUS_STAT                        0x618
+#define USBSS_DEBUG_CFG                        0x708
+#define USBSS_DEBUG_DATA               0x70c
+#define USBSS_HOST_HUB_CTRL            0x714
+
+/* PHY CONFIG register bits */
+#define USBSS_PHY_VBUS_SEL_MASK                GENMASK(2, 1)
+#define USBSS_PHY_VBUS_SEL_SHIFT       1
+#define USBSS_PHY_LANE_REVERSE         BIT(0)
+
+/* MODE CONTROL register bits */
+#define USBSS_MODE_VALID       BIT(0)
+
+/* WAKEUP CONFIG register bits */
+#define USBSS_WAKEUP_CFG_OVERCURRENT_EN        BIT(3)
+#define USBSS_WAKEUP_CFG_LINESTATE_EN  BIT(2)
+#define USBSS_WAKEUP_CFG_SESSVALID_EN  BIT(1)
+#define USBSS_WAKEUP_CFG_VBUSVALID_EN  BIT(0)
+
+/* WAKEUP STAT register bits */
+#define USBSS_WAKEUP_STAT_OVERCURRENT  BIT(4)
+#define USBSS_WAKEUP_STAT_LINESTATE    BIT(3)
+#define USBSS_WAKEUP_STAT_SESSVALID    BIT(2)
+#define USBSS_WAKEUP_STAT_VBUSVALID    BIT(1)
+#define USBSS_WAKEUP_STAT_CLR          BIT(0)
+
+/* IRQ_MISC_STATUS_RAW register bits */
+#define USBSS_IRQ_MISC_RAW_VBUSVALID   BIT(22)
+#define USBSS_IRQ_MISC_RAW_SESSVALID   BIT(20)
+
+/* IRQ_MISC_STATUS register bits */
+#define USBSS_IRQ_MISC_VBUSVALID       BIT(22)
+#define USBSS_IRQ_MISC_SESSVALID       BIT(20)
+
+/* IRQ_MISC_ENABLE_SET register bits */
+#define USBSS_IRQ_MISC_ENABLE_SET_VBUSVALID    BIT(22)
+#define USBSS_IRQ_MISC_ENABLE_SET_SESSVALID    BIT(20)
+
+/* IRQ_MISC_ENABLE_CLR register bits */
+#define USBSS_IRQ_MISC_ENABLE_CLR_VBUSVALID    BIT(22)
+#define USBSS_IRQ_MISC_ENABLE_CLR_SESSVALID    BIT(20)
+
+/* IRQ_MISC_EOI register bits */
+#define USBSS_IRQ_MISC_EOI_VECTOR      BIT(0)
+
+/* VBUS_STAT register bits */
+#define USBSS_VBUS_STAT_SESSVALID      BIT(2)
+#define USBSS_VBUS_STAT_VBUSVALID      BIT(0)
+
+/* Mask for PHY PLL REFCLK */
+#define PHY_PLL_REFCLK_MASK    GENMASK(3, 0)
+
+#define DWC3_AM62_AUTOSUSPEND_DELAY    100
+
+struct dwc3_data {
+       struct device *dev;
+       void __iomem *usbss;
+       struct clk *usb2_refclk;
+       int rate_code;
+       struct regmap *syscon;
+       unsigned int offset;
+       unsigned int vbus_divider;
+};
+
+static const int dwc3_ti_rate_table[] = {      /* in KHZ */
+       9600,
+       10000,
+       12000,
+       19200,
+       20000,
+       24000,
+       25000,
+       26000,
+       38400,
+       40000,
+       58000,
+       50000,
+       52000,
+};
+
+static inline u32 dwc3_ti_readl(struct dwc3_data *data, u32 offset)
+{
+       return readl((data->usbss) + offset);
+}
+
+static inline void dwc3_ti_writel(struct dwc3_data *data, u32 offset, u32 value)
+{
+       writel(value, (data->usbss) + offset);
+}
+
+static int phy_syscon_pll_refclk(struct dwc3_data *data)
+{
+       struct device *dev = data->dev;
+       struct device_node *node = dev->of_node;
+       struct of_phandle_args args;
+       struct regmap *syscon;
+       int ret;
+
+       syscon = syscon_regmap_lookup_by_phandle(node, "ti,syscon-phy-pll-refclk");
+       if (IS_ERR(syscon)) {
+               dev_err(dev, "unable to get ti,syscon-phy-pll-refclk regmap\n");
+               return PTR_ERR(syscon);
+       }
+
+       data->syscon = syscon;
+
+       ret = of_parse_phandle_with_fixed_args(node, "ti,syscon-phy-pll-refclk", 1,
+                                              0, &args);
+       if (ret)
+               return ret;
+
+       data->offset = args.args[0];
+
+       ret = regmap_update_bits(data->syscon, data->offset, PHY_PLL_REFCLK_MASK, data->rate_code);
+       if (ret) {
+               dev_err(dev, "failed to set phy pll reference clock rate\n");
+               return ret;
+       }
+
+       return 0;
+}
+
+static int dwc3_ti_probe(struct platform_device *pdev)
+{
+       struct device *dev = &pdev->dev;
+       struct device_node *node = pdev->dev.of_node;
+       struct dwc3_data *data;
+       int i, ret;
+       unsigned long rate;
+       u32 reg;
+
+       data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+       if (!data)
+               return -ENOMEM;
+
+       data->dev = dev;
+       platform_set_drvdata(pdev, data);
+
+       data->usbss = devm_platform_ioremap_resource(pdev, 0);
+       if (IS_ERR(data->usbss)) {
+               dev_err(dev, "can't map IOMEM resource\n");
+               return PTR_ERR(data->usbss);
+       }
+
+       data->usb2_refclk = devm_clk_get(dev, "ref");
+       if (IS_ERR(data->usb2_refclk)) {
+               dev_err(dev, "can't get usb2_refclk\n");
+               return PTR_ERR(data->usb2_refclk);
+       }
+
+       /* Calculate the rate code */
+       rate = clk_get_rate(data->usb2_refclk);
+       rate /= 1000;   // To KHz
+       for (i = 0; i < ARRAY_SIZE(dwc3_ti_rate_table); i++) {
+               if (dwc3_ti_rate_table[i] == rate)
+                       break;
+       }
+
+       if (i == ARRAY_SIZE(dwc3_ti_rate_table)) {
+               dev_err(dev, "unsupported usb2_refclk rate: %lu KHz\n", rate);
+               ret = -EINVAL;
+               goto err_clk_disable;
+       }
+
+       data->rate_code = i;
+
+       /* Read the syscon property and set the rate code */
+       ret = phy_syscon_pll_refclk(data);
+       if (ret)
+               goto err_clk_disable;
+
+       /* VBUS divider select */
+       data->vbus_divider = device_property_read_bool(dev, "ti,vbus-divider");
+       reg = dwc3_ti_readl(data, USBSS_PHY_CONFIG);
+       if (data->vbus_divider)
+               reg |= 1 << USBSS_PHY_VBUS_SEL_SHIFT;
+
+       dwc3_ti_writel(data, USBSS_PHY_CONFIG, reg);
+
+       pm_runtime_set_active(dev);
+       pm_runtime_enable(dev);
+       /*
+        * Don't ignore its dependencies with its children
+        */
+       pm_suspend_ignore_children(dev, false);
+       clk_prepare_enable(data->usb2_refclk);
+       pm_runtime_get_noresume(dev);
+
+       ret = of_platform_populate(node, NULL, NULL, dev);
+       if (ret) {
+               dev_err(dev, "failed to create dwc3 core: %d\n", ret);
+               goto err_pm_disable;
+       }
+
+       /* Set mode valid bit to indicate role is valid */
+       reg = dwc3_ti_readl(data, USBSS_MODE_CONTROL);
+       reg |= USBSS_MODE_VALID;
+       dwc3_ti_writel(data, USBSS_MODE_CONTROL, reg);
+
+       /* Setting up autosuspend */
+       pm_runtime_set_autosuspend_delay(dev, DWC3_AM62_AUTOSUSPEND_DELAY);
+       pm_runtime_use_autosuspend(dev);
+       pm_runtime_mark_last_busy(dev);
+       pm_runtime_put_autosuspend(dev);
+       return 0;
+
+err_pm_disable:
+       clk_disable_unprepare(data->usb2_refclk);
+       pm_runtime_disable(dev);
+       pm_runtime_set_suspended(dev);
+err_clk_disable:
+       clk_put(data->usb2_refclk);
+       return ret;
+}
+
+static int dwc3_ti_remove_core(struct device *dev, void *c)
+{
+       struct platform_device *pdev = to_platform_device(dev);
+
+       platform_device_unregister(pdev);
+       return 0;
+}
+
+static int dwc3_ti_remove(struct platform_device *pdev)
+{
+       struct device *dev = &pdev->dev;
+       struct dwc3_data *data = platform_get_drvdata(pdev);
+       u32 reg;
+
+       device_for_each_child(dev, NULL, dwc3_ti_remove_core);
+
+       /* Clear mode valid bit */
+       reg = dwc3_ti_readl(data, USBSS_MODE_CONTROL);
+       reg &= ~USBSS_MODE_VALID;
+       dwc3_ti_writel(data, USBSS_MODE_CONTROL, reg);
+
+       pm_runtime_put_sync(dev);
+       clk_disable_unprepare(data->usb2_refclk);
+       pm_runtime_disable(dev);
+       pm_runtime_set_suspended(dev);
+
+       clk_put(data->usb2_refclk);
+       platform_set_drvdata(pdev, NULL);
+       return 0;
+}
+
+#ifdef CONFIG_PM
+static int dwc3_ti_suspend_common(struct device *dev)
+{
+       struct dwc3_data *data = dev_get_drvdata(dev);
+
+       clk_disable_unprepare(data->usb2_refclk);
+
+       return 0;
+}
+
+static int dwc3_ti_resume_common(struct device *dev)
+{
+       struct dwc3_data *data = dev_get_drvdata(dev);
+
+       clk_prepare_enable(data->usb2_refclk);
+
+       return 0;
+}
+
+static UNIVERSAL_DEV_PM_OPS(dwc3_ti_pm_ops, dwc3_ti_suspend_common,
+                           dwc3_ti_resume_common, NULL);
+
+#define DEV_PM_OPS     (&dwc3_ti_pm_ops)
+#else
+#define DEV_PM_OPS     NULL
+#endif /* CONFIG_PM */
+
+static const struct of_device_id dwc3_ti_of_match[] = {
+       { .compatible = "ti,am62-usb"},
+       {},
+};
+MODULE_DEVICE_TABLE(of, dwc3_ti_of_match);
+
+static struct platform_driver dwc3_ti_driver = {
+       .probe          = dwc3_ti_probe,
+       .remove         = dwc3_ti_remove,
+       .driver         = {
+               .name   = "dwc3-am62",
+               .pm     = DEV_PM_OPS,
+               .of_match_table = dwc3_ti_of_match,
+       },
+};
+
+module_platform_driver(dwc3_ti_driver);
+
+MODULE_ALIAS("platform:dwc3-am62");
+MODULE_AUTHOR("Aswath Govindraju <a-govindraju@ti.com>");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("DesignWare USB3 TI Glue Layer");