--- /dev/null
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * USB Glue for Amlogic G12A SoCs
+ *
+ * Copyright (c) 2019 BayLibre, SAS
+ * Author: Neil Armstrong <narmstrong@baylibre.com>
+ */
+
+/*
+ * The USB is organized with a glue around the DWC3 Controller IP as :
+ * - Control registers for each USB2 Ports
+ * - Control registers for the USB PHY layer
+ * - SuperSpeed PHY can be enabled only if port is used
+ *
+ * TOFIX:
+ * - Add dynamic OTG switching with ID change interrupt
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+#include <linux/clk.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/pm_runtime.h>
+#include <linux/regmap.h>
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
+#include <linux/reset.h>
+#include <linux/phy/phy.h>
+#include <linux/usb/otg.h>
+#include <linux/usb/role.h>
+#include <linux/regulator/consumer.h>
+
+/* USB2 Ports Control Registers */
+
+#define U2P_REG_SIZE 0x20
+
+#define U2P_R0 0x0
+ #define U2P_R0_HOST_DEVICE BIT(0)
+ #define U2P_R0_POWER_OK BIT(1)
+ #define U2P_R0_HAST_MODE BIT(2)
+ #define U2P_R0_POWER_ON_RESET BIT(3)
+ #define U2P_R0_ID_PULLUP BIT(4)
+ #define U2P_R0_DRV_VBUS BIT(5)
+
+#define U2P_R1 0x4
+ #define U2P_R1_PHY_READY BIT(0)
+ #define U2P_R1_ID_DIG BIT(1)
+ #define U2P_R1_OTG_SESSION_VALID BIT(2)
+ #define U2P_R1_VBUS_VALID BIT(3)
+
+/* USB Glue Control Registers */
+
+#define USB_R0 0x80
+ #define USB_R0_P30_LANE0_TX2RX_LOOPBACK BIT(17)
+ #define USB_R0_P30_LANE0_EXT_PCLK_REQ BIT(18)
+ #define USB_R0_P30_PCS_RX_LOS_MASK_VAL_MASK GENMASK(28, 19)
+ #define USB_R0_U2D_SS_SCALEDOWN_MODE_MASK GENMASK(30, 29)
+ #define USB_R0_U2D_ACT BIT(31)
+
+#define USB_R1 0x84
+ #define USB_R1_U3H_BIGENDIAN_GS BIT(0)
+ #define USB_R1_U3H_PME_ENABLE BIT(1)
+ #define USB_R1_U3H_HUB_PORT_OVERCURRENT_MASK GENMASK(4, 2)
+ #define USB_R1_U3H_HUB_PORT_PERM_ATTACH_MASK GENMASK(9, 7)
+ #define USB_R1_U3H_HOST_U2_PORT_DISABLE_MASK GENMASK(13, 12)
+ #define USB_R1_U3H_HOST_U3_PORT_DISABLE BIT(16)
+ #define USB_R1_U3H_HOST_PORT_POWER_CONTROL_PRESENT BIT(17)
+ #define USB_R1_U3H_HOST_MSI_ENABLE BIT(18)
+ #define USB_R1_U3H_FLADJ_30MHZ_REG_MASK GENMASK(24, 19)
+ #define USB_R1_P30_PCS_TX_SWING_FULL_MASK GENMASK(31, 25)
+
+#define USB_R2 0x88
+ #define USB_R2_P30_PCS_TX_DEEMPH_3P5DB_MASK GENMASK(25, 20)
+ #define USB_R2_P30_PCS_TX_DEEMPH_6DB_MASK GENMASK(31, 26)
+
+#define USB_R3 0x8c
+ #define USB_R3_P30_SSC_ENABLE BIT(0)
+ #define USB_R3_P30_SSC_RANGE_MASK GENMASK(3, 1)
+ #define USB_R3_P30_SSC_REF_CLK_SEL_MASK GENMASK(12, 4)
+ #define USB_R3_P30_REF_SSP_EN BIT(13)
+
+#define USB_R4 0x90
+ #define USB_R4_P21_PORT_RESET_0 BIT(0)
+ #define USB_R4_P21_SLEEP_M0 BIT(1)
+ #define USB_R4_MEM_PD_MASK GENMASK(3, 2)
+ #define USB_R4_P21_ONLY BIT(4)
+
+#define USB_R5 0x94
+ #define USB_R5_ID_DIG_SYNC BIT(0)
+ #define USB_R5_ID_DIG_REG BIT(1)
+ #define USB_R5_ID_DIG_CFG_MASK GENMASK(3, 2)
+ #define USB_R5_ID_DIG_EN_0 BIT(4)
+ #define USB_R5_ID_DIG_EN_1 BIT(5)
+ #define USB_R5_ID_DIG_CURR BIT(6)
+ #define USB_R5_ID_DIG_IRQ BIT(7)
+ #define USB_R5_ID_DIG_TH_MASK GENMASK(15, 8)
+ #define USB_R5_ID_DIG_CNT_MASK GENMASK(23, 16)
+
+enum {
+ USB2_HOST_PHY = 0,
+ USB2_OTG_PHY,
+ USB3_HOST_PHY,
+ PHY_COUNT,
+};
+
+static const char *phy_names[PHY_COUNT] = {
+ "usb2-phy0", "usb2-phy1", "usb3-phy0",
+};
+
+struct dwc3_meson_g12a {
+ struct device *dev;
+ struct regmap *regmap;
+ struct clk *clk;
+ struct reset_control *reset;
+ struct phy *phys[PHY_COUNT];
+ enum usb_dr_mode otg_mode;
+ enum phy_mode otg_phy_mode;
+ unsigned int usb2_ports;
+ unsigned int usb3_ports;
+ struct regulator *vbus;
+ struct usb_role_switch_desc switch_desc;
+ struct usb_role_switch *role_switch;
+};
+
+static void dwc3_meson_g12a_usb2_set_mode(struct dwc3_meson_g12a *priv,
+ int i, enum phy_mode mode)
+{
+ if (mode == PHY_MODE_USB_HOST)
+ regmap_update_bits(priv->regmap, U2P_R0 + (U2P_REG_SIZE * i),
+ U2P_R0_HOST_DEVICE,
+ U2P_R0_HOST_DEVICE);
+ else
+ regmap_update_bits(priv->regmap, U2P_R0 + (U2P_REG_SIZE * i),
+ U2P_R0_HOST_DEVICE, 0);
+}
+
+static int dwc3_meson_g12a_usb2_init(struct dwc3_meson_g12a *priv)
+{
+ int i;
+
+ if (priv->otg_mode == USB_DR_MODE_PERIPHERAL)
+ priv->otg_phy_mode = PHY_MODE_USB_DEVICE;
+ else
+ priv->otg_phy_mode = PHY_MODE_USB_HOST;
+
+ for (i = 0 ; i < USB3_HOST_PHY ; ++i) {
+ if (!priv->phys[i])
+ continue;
+
+ regmap_update_bits(priv->regmap, U2P_R0 + (U2P_REG_SIZE * i),
+ U2P_R0_POWER_ON_RESET,
+ U2P_R0_POWER_ON_RESET);
+
+ if (i == USB2_OTG_PHY) {
+ regmap_update_bits(priv->regmap,
+ U2P_R0 + (U2P_REG_SIZE * i),
+ U2P_R0_ID_PULLUP | U2P_R0_DRV_VBUS,
+ U2P_R0_ID_PULLUP | U2P_R0_DRV_VBUS);
+
+ dwc3_meson_g12a_usb2_set_mode(priv, i,
+ priv->otg_phy_mode);
+ } else
+ dwc3_meson_g12a_usb2_set_mode(priv, i,
+ PHY_MODE_USB_HOST);
+
+ regmap_update_bits(priv->regmap, U2P_R0 + (U2P_REG_SIZE * i),
+ U2P_R0_POWER_ON_RESET, 0);
+ }
+
+ return 0;
+}
+
+static void dwc3_meson_g12a_usb3_init(struct dwc3_meson_g12a *priv)
+{
+ regmap_update_bits(priv->regmap, USB_R3,
+ USB_R3_P30_SSC_RANGE_MASK |
+ USB_R3_P30_REF_SSP_EN,
+ USB_R3_P30_SSC_ENABLE |
+ FIELD_PREP(USB_R3_P30_SSC_RANGE_MASK, 2) |
+ USB_R3_P30_REF_SSP_EN);
+ udelay(2);
+
+ regmap_update_bits(priv->regmap, USB_R2,
+ USB_R2_P30_PCS_TX_DEEMPH_3P5DB_MASK,
+ FIELD_PREP(USB_R2_P30_PCS_TX_DEEMPH_3P5DB_MASK, 0x15));
+
+ regmap_update_bits(priv->regmap, USB_R2,
+ USB_R2_P30_PCS_TX_DEEMPH_6DB_MASK,
+ FIELD_PREP(USB_R2_P30_PCS_TX_DEEMPH_6DB_MASK, 0x20));
+
+ udelay(2);
+
+ regmap_update_bits(priv->regmap, USB_R1,
+ USB_R1_U3H_HOST_PORT_POWER_CONTROL_PRESENT,
+ USB_R1_U3H_HOST_PORT_POWER_CONTROL_PRESENT);
+
+ regmap_update_bits(priv->regmap, USB_R1,
+ USB_R1_P30_PCS_TX_SWING_FULL_MASK,
+ FIELD_PREP(USB_R1_P30_PCS_TX_SWING_FULL_MASK, 127));
+}
+
+static void dwc3_meson_g12a_usb_otg_apply_mode(struct dwc3_meson_g12a *priv)
+{
+ if (priv->otg_phy_mode == PHY_MODE_USB_DEVICE) {
+ regmap_update_bits(priv->regmap, USB_R0,
+ USB_R0_U2D_ACT, USB_R0_U2D_ACT);
+ regmap_update_bits(priv->regmap, USB_R0,
+ USB_R0_U2D_SS_SCALEDOWN_MODE_MASK, 0);
+ regmap_update_bits(priv->regmap, USB_R4,
+ USB_R4_P21_SLEEP_M0, USB_R4_P21_SLEEP_M0);
+ } else {
+ regmap_update_bits(priv->regmap, USB_R0,
+ USB_R0_U2D_ACT, 0);
+ regmap_update_bits(priv->regmap, USB_R4,
+ USB_R4_P21_SLEEP_M0, 0);
+ }
+}
+
+static int dwc3_meson_g12a_usb_init(struct dwc3_meson_g12a *priv)
+{
+ int ret;
+
+ ret = dwc3_meson_g12a_usb2_init(priv);
+ if (ret)
+ return ret;
+
+ regmap_update_bits(priv->regmap, USB_R1,
+ USB_R1_U3H_FLADJ_30MHZ_REG_MASK,
+ FIELD_PREP(USB_R1_U3H_FLADJ_30MHZ_REG_MASK, 0x20));
+
+ regmap_update_bits(priv->regmap, USB_R5,
+ USB_R5_ID_DIG_EN_0,
+ USB_R5_ID_DIG_EN_0);
+ regmap_update_bits(priv->regmap, USB_R5,
+ USB_R5_ID_DIG_EN_1,
+ USB_R5_ID_DIG_EN_1);
+ regmap_update_bits(priv->regmap, USB_R5,
+ USB_R5_ID_DIG_TH_MASK,
+ FIELD_PREP(USB_R5_ID_DIG_TH_MASK, 0xff));
+
+ /* If we have an actual SuperSpeed port, initialize it */
+ if (priv->usb3_ports)
+ dwc3_meson_g12a_usb3_init(priv);
+
+ dwc3_meson_g12a_usb_otg_apply_mode(priv);
+
+ return 0;
+}
+
+static const struct regmap_config phy_meson_g12a_usb3_regmap_conf = {
+ .reg_bits = 8,
+ .val_bits = 32,
+ .reg_stride = 4,
+ .max_register = USB_R5,
+};
+
+static int dwc3_meson_g12a_get_phys(struct dwc3_meson_g12a *priv)
+{
+ int i;
+
+ for (i = 0 ; i < PHY_COUNT ; ++i) {
+ priv->phys[i] = devm_phy_optional_get(priv->dev, phy_names[i]);
+ if (!priv->phys[i])
+ continue;
+
+ if (IS_ERR(priv->phys[i]))
+ return PTR_ERR(priv->phys[i]);
+
+ if (i == USB3_HOST_PHY)
+ priv->usb3_ports++;
+ else
+ priv->usb2_ports++;
+ }
+
+ dev_info(priv->dev, "USB2 ports: %d\n", priv->usb2_ports);
+ dev_info(priv->dev, "USB3 ports: %d\n", priv->usb3_ports);
+
+ return 0;
+}
+
+static enum phy_mode dwc3_meson_g12a_get_id(struct dwc3_meson_g12a *priv)
+{
+ u32 reg;
+
+ regmap_read(priv->regmap, USB_R5, ®);
+
+ if (reg & (USB_R5_ID_DIG_SYNC | USB_R5_ID_DIG_REG))
+ return PHY_MODE_USB_DEVICE;
+
+ return PHY_MODE_USB_HOST;
+}
+
+static int dwc3_meson_g12a_otg_mode_set(struct dwc3_meson_g12a *priv,
+ enum phy_mode mode)
+{
+ int ret;
+
+ if (!priv->phys[USB2_OTG_PHY])
+ return -EINVAL;
+
+ if (mode == PHY_MODE_USB_HOST)
+ dev_info(priv->dev, "switching to Host Mode\n");
+ else
+ dev_info(priv->dev, "switching to Device Mode\n");
+
+ if (priv->vbus) {
+ if (mode == PHY_MODE_USB_DEVICE)
+ ret = regulator_disable(priv->vbus);
+ else
+ ret = regulator_enable(priv->vbus);
+ if (ret)
+ return ret;
+ }
+
+ priv->otg_phy_mode = mode;
+
+ dwc3_meson_g12a_usb2_set_mode(priv, USB2_OTG_PHY, mode);
+
+ dwc3_meson_g12a_usb_otg_apply_mode(priv);
+
+ return 0;
+}
+
+static int dwc3_meson_g12a_role_set(struct device *dev, enum usb_role role)
+{
+ struct dwc3_meson_g12a *priv = dev_get_drvdata(dev);
+ enum phy_mode mode;
+
+ if (role == USB_ROLE_NONE)
+ return 0;
+
+ mode = (role == USB_ROLE_HOST) ? PHY_MODE_USB_HOST
+ : PHY_MODE_USB_DEVICE;
+
+ if (mode == priv->otg_phy_mode)
+ return 0;
+
+ return dwc3_meson_g12a_otg_mode_set(priv, mode);
+}
+
+static enum usb_role dwc3_meson_g12a_role_get(struct device *dev)
+{
+ struct dwc3_meson_g12a *priv = dev_get_drvdata(dev);
+
+ return priv->otg_phy_mode == PHY_MODE_USB_HOST ?
+ USB_ROLE_HOST : USB_ROLE_DEVICE;
+}
+
+static struct device *dwc3_meson_g12_find_child(struct device *dev,
+ const char *compatible)
+{
+ struct platform_device *pdev;
+ struct device_node *np;
+
+ np = of_get_compatible_child(dev->of_node, compatible);
+ if (!np)
+ return NULL;
+
+ pdev = of_find_device_by_node(np);
+ of_node_put(np);
+ if (!pdev)
+ return NULL;
+
+ return &pdev->dev;
+}
+
+static int dwc3_meson_g12a_probe(struct platform_device *pdev)
+{
+ struct dwc3_meson_g12a *priv;
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+ void __iomem *base;
+ struct resource *res;
+ enum phy_mode otg_id;
+ int ret, i;
+
+ priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ base = devm_ioremap_resource(dev, res);
+ if (IS_ERR(base))
+ return PTR_ERR(base);
+
+ priv->regmap = devm_regmap_init_mmio(dev, base,
+ &phy_meson_g12a_usb3_regmap_conf);
+ if (IS_ERR(priv->regmap))
+ return PTR_ERR(priv->regmap);
+
+ priv->vbus = devm_regulator_get_optional(dev, "vbus");
+ if (IS_ERR(priv->vbus)) {
+ if (PTR_ERR(priv->vbus) == -EPROBE_DEFER)
+ return PTR_ERR(priv->vbus);
+ priv->vbus = NULL;
+ }
+
+ priv->clk = devm_clk_get(dev, NULL);
+ if (IS_ERR(priv->clk))
+ return PTR_ERR(priv->clk);
+
+ ret = clk_prepare_enable(priv->clk);
+ if (ret)
+ return ret;
+
+ devm_add_action_or_reset(dev,
+ (void(*)(void *))clk_disable_unprepare,
+ priv->clk);
+
+ platform_set_drvdata(pdev, priv);
+ priv->dev = dev;
+
+ priv->reset = devm_reset_control_get(dev, NULL);
+ if (IS_ERR(priv->reset)) {
+ ret = PTR_ERR(priv->reset);
+ dev_err(dev, "failed to get device reset, err=%d\n", ret);
+ return ret;
+ }
+
+ ret = reset_control_reset(priv->reset);
+ if (ret)
+ return ret;
+
+ ret = dwc3_meson_g12a_get_phys(priv);
+ if (ret)
+ return ret;
+
+ if (priv->vbus) {
+ ret = regulator_enable(priv->vbus);
+ if (ret)
+ return ret;
+ }
+
+ /* Get dr_mode */
+ priv->otg_mode = usb_get_dr_mode(dev);
+
+ dwc3_meson_g12a_usb_init(priv);
+
+ /* Init PHYs */
+ for (i = 0 ; i < PHY_COUNT ; ++i) {
+ ret = phy_init(priv->phys[i]);
+ if (ret)
+ return ret;
+ }
+
+ /* Set PHY Power */
+ for (i = 0 ; i < PHY_COUNT ; ++i) {
+ ret = phy_power_on(priv->phys[i]);
+ if (ret)
+ goto err_phys_exit;
+ }
+
+ ret = of_platform_populate(np, NULL, NULL, dev);
+ if (ret) {
+ clk_disable_unprepare(priv->clk);
+ goto err_phys_power;
+ }
+
+ /* Setup OTG mode corresponding to the ID pin */
+ if (priv->otg_mode == USB_DR_MODE_OTG) {
+ /* TOFIX Handle ID mode toggling via IRQ */
+ otg_id = dwc3_meson_g12a_get_id(priv);
+ if (otg_id != priv->otg_phy_mode) {
+ if (dwc3_meson_g12a_otg_mode_set(priv, otg_id))
+ dev_warn(dev, "Failed to switch OTG mode\n");
+ }
+ }
+
+ /* Setup role switcher */
+ priv->switch_desc.usb2_port = dwc3_meson_g12_find_child(dev,
+ "snps,dwc3");
+ priv->switch_desc.udc = dwc3_meson_g12_find_child(dev, "snps,dwc2");
+ priv->switch_desc.allow_userspace_control = true;
+ priv->switch_desc.set = dwc3_meson_g12a_role_set;
+ priv->switch_desc.get = dwc3_meson_g12a_role_get;
+
+ priv->role_switch = usb_role_switch_register(dev, &priv->switch_desc);
+ if (IS_ERR(priv->role_switch))
+ dev_warn(dev, "Unable to register Role Switch\n");
+
+ pm_runtime_set_active(dev);
+ pm_runtime_enable(dev);
+ pm_runtime_get_sync(dev);
+
+ return 0;
+
+err_phys_power:
+ for (i = 0 ; i < PHY_COUNT ; ++i)
+ phy_power_off(priv->phys[i]);
+
+err_phys_exit:
+ for (i = 0 ; i < PHY_COUNT ; ++i)
+ phy_exit(priv->phys[i]);
+
+ return ret;
+}
+
+static int dwc3_meson_g12a_remove(struct platform_device *pdev)
+{
+ struct dwc3_meson_g12a *priv = platform_get_drvdata(pdev);
+ struct device *dev = &pdev->dev;
+ int i;
+
+ usb_role_switch_unregister(priv->role_switch);
+
+ of_platform_depopulate(dev);
+
+ for (i = 0 ; i < PHY_COUNT ; ++i) {
+ phy_power_off(priv->phys[i]);
+ phy_exit(priv->phys[i]);
+ }
+
+ pm_runtime_disable(dev);
+ pm_runtime_put_noidle(dev);
+ pm_runtime_set_suspended(dev);
+
+ return 0;
+}
+
+static int __maybe_unused dwc3_meson_g12a_runtime_suspend(struct device *dev)
+{
+ struct dwc3_meson_g12a *priv = dev_get_drvdata(dev);
+
+ clk_disable(priv->clk);
+
+ return 0;
+}
+
+static int __maybe_unused dwc3_meson_g12a_runtime_resume(struct device *dev)
+{
+ struct dwc3_meson_g12a *priv = dev_get_drvdata(dev);
+
+ return clk_enable(priv->clk);
+}
+
+static int __maybe_unused dwc3_meson_g12a_suspend(struct device *dev)
+{
+ struct dwc3_meson_g12a *priv = dev_get_drvdata(dev);
+ int i;
+
+ for (i = 0 ; i < PHY_COUNT ; ++i) {
+ phy_power_off(priv->phys[i]);
+ phy_exit(priv->phys[i]);
+ }
+
+ reset_control_assert(priv->reset);
+
+ return 0;
+}
+
+static int __maybe_unused dwc3_meson_g12a_resume(struct device *dev)
+{
+ struct dwc3_meson_g12a *priv = dev_get_drvdata(dev);
+ int i, ret;
+
+ reset_control_deassert(priv->reset);
+
+ dwc3_meson_g12a_usb_init(priv);
+
+ /* Init PHYs */
+ for (i = 0 ; i < PHY_COUNT ; ++i) {
+ ret = phy_init(priv->phys[i]);
+ if (ret)
+ return ret;
+ }
+
+ /* Set PHY Power */
+ for (i = 0 ; i < PHY_COUNT ; ++i) {
+ ret = phy_power_on(priv->phys[i]);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+
+static const struct dev_pm_ops dwc3_meson_g12a_dev_pm_ops = {
+ SET_SYSTEM_SLEEP_PM_OPS(dwc3_meson_g12a_suspend, dwc3_meson_g12a_resume)
+ SET_RUNTIME_PM_OPS(dwc3_meson_g12a_runtime_suspend,
+ dwc3_meson_g12a_runtime_resume, NULL)
+};
+
+static const struct of_device_id dwc3_meson_g12a_match[] = {
+ { .compatible = "amlogic,meson-g12a-usb-ctrl" },
+ { /* Sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, dwc3_meson_g12a_match);
+
+static struct platform_driver dwc3_meson_g12a_driver = {
+ .probe = dwc3_meson_g12a_probe,
+ .remove = dwc3_meson_g12a_remove,
+ .driver = {
+ .name = "dwc3-meson-g12a",
+ .of_match_table = dwc3_meson_g12a_match,
+ .pm = &dwc3_meson_g12a_dev_pm_ops,
+ },
+};
+
+module_platform_driver(dwc3_meson_g12a_driver);
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Amlogic Meson G12A USB Glue Layer");
+MODULE_AUTHOR("Neil Armstrong <narmstrong@baylibre.com>");
projects / platform / kernel / linux-rpi.git / commitdiff