xref: /openbmc/linux/drivers/usb/dwc3/dwc3-meson-g12a.c (revision 347052e3)

// 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
 * - 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, offsets are per-port */

#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 G12A_GLUE_OFFSET					0x80

#define USB_R0							0x00
	#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							0x04
	#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							0x08
	#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							0x0c
	#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							0x10
	#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							0x14
	#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)

#define PHY_COUNT						3
#define USB2_OTG_PHY						1

static struct clk_bulk_data meson_gxl_clocks[] = {
	{ .id = "usb_ctrl" },
	{ .id = "ddr" },
};

static struct clk_bulk_data meson_g12a_clocks[] = {
	{ .id = NULL },
};

static struct clk_bulk_data meson_a1_clocks[] = {
	{ .id = "usb_ctrl" },
	{ .id = "usb_bus" },
	{ .id = "xtal_usb_ctrl" },
};

static const char *meson_gxm_phy_names[] = {
	"usb2-phy0", "usb2-phy1", "usb2-phy2",
};

static const char *meson_g12a_phy_names[] = {
	"usb2-phy0", "usb2-phy1", "usb3-phy0",
};

/*
 * Amlogic A1 has a single physical PHY, in slot 1, but still has the
 * two U2 PHY controls register blocks like G12A.
 * Handling the first PHY on slot 1 would need a large amount of code
 * changes, and the current management is generic enough to handle it
 * correctly when only the "usb2-phy1" phy is specified on-par with the
 * DT bindings.
 */
static const char *meson_a1_phy_names[] = {
	"usb2-phy0", "usb2-phy1"
};

struct dwc3_meson_g12a;

struct dwc3_meson_g12a_drvdata {
	bool otg_switch_supported;
	bool otg_phy_host_port_disable;
	struct clk_bulk_data *clks;
	int num_clks;
	const char **phy_names;
	int num_phys;
	int (*setup_regmaps)(struct dwc3_meson_g12a *priv, void __iomem *base);
	int (*usb2_init_phy)(struct dwc3_meson_g12a *priv, int i,
			     enum phy_mode mode);
	int (*set_phy_mode)(struct dwc3_meson_g12a *priv, int i,
			    enum phy_mode mode);
	int (*usb_init)(struct dwc3_meson_g12a *priv);
	int (*usb_post_init)(struct dwc3_meson_g12a *priv);
};

static int dwc3_meson_gxl_setup_regmaps(struct dwc3_meson_g12a *priv,
					void __iomem *base);
static int dwc3_meson_g12a_setup_regmaps(struct dwc3_meson_g12a *priv,
					 void __iomem *base);

static int dwc3_meson_g12a_usb2_init_phy(struct dwc3_meson_g12a *priv, int i,
					 enum phy_mode mode);
static int dwc3_meson_gxl_usb2_init_phy(struct dwc3_meson_g12a *priv, int i,
					enum phy_mode mode);

static int dwc3_meson_g12a_set_phy_mode(struct dwc3_meson_g12a *priv,
					int i, enum phy_mode mode);
static int dwc3_meson_gxl_set_phy_mode(struct dwc3_meson_g12a *priv,
				       int i, enum phy_mode mode);

static int dwc3_meson_g12a_usb_init(struct dwc3_meson_g12a *priv);
static int dwc3_meson_gxl_usb_init(struct dwc3_meson_g12a *priv);

static int dwc3_meson_gxl_usb_post_init(struct dwc3_meson_g12a *priv);

/*
 * For GXL and GXM SoCs:
 * USB Phy muxing between the DWC2 Device controller and the DWC3 Host
 * controller is buggy when switching from Device to Host when USB port
 * is unpopulated, it causes the DWC3 to hard crash.
 * When populated (including OTG switching with ID pin), the switch works
 * like a charm like on the G12A platforms.
 * In order to still switch from Host to Device on an USB Type-A port,
 * an U2_PORT_DISABLE bit has been added to disconnect the DWC3 Host
 * controller from the port, but when used the DWC3 controller must be
 * reset to recover usage of the port.
 */

static struct dwc3_meson_g12a_drvdata gxl_drvdata = {
	.otg_switch_supported = true,
	.otg_phy_host_port_disable = true,
	.clks = meson_gxl_clocks,
	.num_clks = ARRAY_SIZE(meson_g12a_clocks),
	.phy_names = meson_a1_phy_names,
	.num_phys = ARRAY_SIZE(meson_a1_phy_names),
	.setup_regmaps = dwc3_meson_gxl_setup_regmaps,
	.usb2_init_phy = dwc3_meson_gxl_usb2_init_phy,
	.set_phy_mode = dwc3_meson_gxl_set_phy_mode,
	.usb_init = dwc3_meson_gxl_usb_init,
	.usb_post_init = dwc3_meson_gxl_usb_post_init,
};

static struct dwc3_meson_g12a_drvdata gxm_drvdata = {
	.otg_switch_supported = true,
	.otg_phy_host_port_disable = true,
	.clks = meson_gxl_clocks,
	.num_clks = ARRAY_SIZE(meson_g12a_clocks),
	.phy_names = meson_gxm_phy_names,
	.num_phys = ARRAY_SIZE(meson_gxm_phy_names),
	.setup_regmaps = dwc3_meson_gxl_setup_regmaps,
	.usb2_init_phy = dwc3_meson_gxl_usb2_init_phy,
	.set_phy_mode = dwc3_meson_gxl_set_phy_mode,
	.usb_init = dwc3_meson_gxl_usb_init,
	.usb_post_init = dwc3_meson_gxl_usb_post_init,
};

static struct dwc3_meson_g12a_drvdata g12a_drvdata = {
	.otg_switch_supported = true,
	.clks = meson_g12a_clocks,
	.num_clks = ARRAY_SIZE(meson_g12a_clocks),
	.phy_names = meson_g12a_phy_names,
	.num_phys = ARRAY_SIZE(meson_g12a_phy_names),
	.setup_regmaps = dwc3_meson_g12a_setup_regmaps,
	.usb2_init_phy = dwc3_meson_g12a_usb2_init_phy,
	.set_phy_mode = dwc3_meson_g12a_set_phy_mode,
	.usb_init = dwc3_meson_g12a_usb_init,
};

static struct dwc3_meson_g12a_drvdata a1_drvdata = {
	.otg_switch_supported = false,
	.clks = meson_a1_clocks,
	.num_clks = ARRAY_SIZE(meson_a1_clocks),
	.phy_names = meson_a1_phy_names,
	.num_phys = ARRAY_SIZE(meson_a1_phy_names),
	.setup_regmaps = dwc3_meson_g12a_setup_regmaps,
	.usb2_init_phy = dwc3_meson_g12a_usb2_init_phy,
	.set_phy_mode = dwc3_meson_g12a_set_phy_mode,
	.usb_init = dwc3_meson_g12a_usb_init,
};

struct dwc3_meson_g12a {
	struct device		*dev;
	struct regmap		*u2p_regmap[PHY_COUNT];
	struct regmap		*usb_glue_regmap;
	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;
	const struct dwc3_meson_g12a_drvdata *drvdata;
};

static int dwc3_meson_gxl_set_phy_mode(struct dwc3_meson_g12a *priv,
					 int i, enum phy_mode mode)
{
	return phy_set_mode(priv->phys[i], mode);
}

static int dwc3_meson_gxl_usb2_init_phy(struct dwc3_meson_g12a *priv, int i,
					enum phy_mode mode)
{
	/* On GXL PHY must be started in device mode for DWC2 init */
	return priv->drvdata->set_phy_mode(priv, i,
				(i == USB2_OTG_PHY) ? PHY_MODE_USB_DEVICE
						    : PHY_MODE_USB_HOST);
}

static int dwc3_meson_g12a_set_phy_mode(struct dwc3_meson_g12a *priv,
					 int i, enum phy_mode mode)
{
	if (mode == PHY_MODE_USB_HOST)
		regmap_update_bits(priv->u2p_regmap[i], U2P_R0,
				U2P_R0_HOST_DEVICE,
				U2P_R0_HOST_DEVICE);
	else
		regmap_update_bits(priv->u2p_regmap[i], U2P_R0,
				U2P_R0_HOST_DEVICE, 0);

	return 0;
}

static int dwc3_meson_g12a_usb2_init_phy(struct dwc3_meson_g12a *priv, int i,
					 enum phy_mode mode)
{
	int ret;

	regmap_update_bits(priv->u2p_regmap[i], U2P_R0,
			U2P_R0_POWER_ON_RESET,
			U2P_R0_POWER_ON_RESET);

	if (priv->drvdata->otg_switch_supported && i == USB2_OTG_PHY) {
		regmap_update_bits(priv->u2p_regmap[i], U2P_R0,
				   U2P_R0_ID_PULLUP | U2P_R0_DRV_VBUS,
				   U2P_R0_ID_PULLUP | U2P_R0_DRV_VBUS);

		ret = priv->drvdata->set_phy_mode(priv, i, mode);
	} else
		ret = priv->drvdata->set_phy_mode(priv, i,
						  PHY_MODE_USB_HOST);

	if (ret)
		return ret;

	regmap_update_bits(priv->u2p_regmap[i], U2P_R0,
			U2P_R0_POWER_ON_RESET, 0);

	return 0;
}

static int dwc3_meson_g12a_usb2_init(struct dwc3_meson_g12a *priv,
				     enum phy_mode mode)
{
	int i, ret;

	for (i = 0; i < priv->drvdata->num_phys; ++i) {
		if (!priv->phys[i])
			continue;

		if (!strstr(priv->drvdata->phy_names[i], "usb2"))
			continue;

		ret = priv->drvdata->usb2_init_phy(priv, i, mode);
		if (ret)
			return ret;
	}

	return 0;
}

static void dwc3_meson_g12a_usb3_init(struct dwc3_meson_g12a *priv)
{
	regmap_update_bits(priv->usb_glue_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->usb_glue_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->usb_glue_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->usb_glue_regmap, USB_R1,
			USB_R1_U3H_HOST_PORT_POWER_CONTROL_PRESENT,
			USB_R1_U3H_HOST_PORT_POWER_CONTROL_PRESENT);

	regmap_update_bits(priv->usb_glue_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,
					       enum phy_mode mode)
{
	if (mode == PHY_MODE_USB_DEVICE) {
		if (priv->otg_mode != USB_DR_MODE_OTG &&
		    priv->drvdata->otg_phy_host_port_disable)
			/* Isolate the OTG PHY port from the Host Controller */
			regmap_update_bits(priv->usb_glue_regmap, USB_R1,
				USB_R1_U3H_HOST_U2_PORT_DISABLE_MASK,
				FIELD_PREP(USB_R1_U3H_HOST_U2_PORT_DISABLE_MASK,
					   BIT(USB2_OTG_PHY)));

		regmap_update_bits(priv->usb_glue_regmap, USB_R0,
				USB_R0_U2D_ACT, USB_R0_U2D_ACT);
		regmap_update_bits(priv->usb_glue_regmap, USB_R0,
				USB_R0_U2D_SS_SCALEDOWN_MODE_MASK, 0);
		regmap_update_bits(priv->usb_glue_regmap, USB_R4,
				USB_R4_P21_SLEEP_M0, USB_R4_P21_SLEEP_M0);
	} else {
		if (priv->otg_mode != USB_DR_MODE_OTG &&
		    priv->drvdata->otg_phy_host_port_disable) {
			regmap_update_bits(priv->usb_glue_regmap, USB_R1,
				USB_R1_U3H_HOST_U2_PORT_DISABLE_MASK, 0);
			msleep(500);
		}
		regmap_update_bits(priv->usb_glue_regmap, USB_R0,
				USB_R0_U2D_ACT, 0);
		regmap_update_bits(priv->usb_glue_regmap, USB_R4,
				USB_R4_P21_SLEEP_M0, 0);
	}
}

static int dwc3_meson_g12a_usb_init_glue(struct dwc3_meson_g12a *priv,
					 enum phy_mode mode)
{
	int ret;

	ret = dwc3_meson_g12a_usb2_init(priv, mode);
	if (ret)
		return ret;

	regmap_update_bits(priv->usb_glue_regmap, USB_R1,
			USB_R1_U3H_FLADJ_30MHZ_REG_MASK,
			FIELD_PREP(USB_R1_U3H_FLADJ_30MHZ_REG_MASK, 0x20));

	regmap_update_bits(priv->usb_glue_regmap, USB_R5,
			USB_R5_ID_DIG_EN_0,
			USB_R5_ID_DIG_EN_0);
	regmap_update_bits(priv->usb_glue_regmap, USB_R5,
			USB_R5_ID_DIG_EN_1,
			USB_R5_ID_DIG_EN_1);
	regmap_update_bits(priv->usb_glue_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, mode);

	return 0;
}

static const struct regmap_config phy_meson_g12a_usb_glue_regmap_conf = {
	.name = "usb-glue",
	.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)
{
	const char *phy_name;
	int i;

	for (i = 0 ; i < priv->drvdata->num_phys ; ++i) {
		phy_name = priv->drvdata->phy_names[i];
		priv->phys[i] = devm_phy_optional_get(priv->dev, phy_name);
		if (!priv->phys[i])
			continue;

		if (IS_ERR(priv->phys[i]))
			return PTR_ERR(priv->phys[i]);

		if (strstr(phy_name, "usb3"))
			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->usb_glue_regmap, USB_R5, &reg);

	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->drvdata->otg_switch_supported || !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;

	ret = priv->drvdata->set_phy_mode(priv, USB2_OTG_PHY, mode);
	if (ret)
		return ret;

	dwc3_meson_g12a_usb_otg_apply_mode(priv, mode);

	return 0;
}

static int dwc3_meson_g12a_role_set(struct usb_role_switch *sw,
				    enum usb_role role)
{
	struct dwc3_meson_g12a *priv = usb_role_switch_get_drvdata(sw);
	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;

	if (priv->drvdata->otg_phy_host_port_disable)
		dev_warn_once(priv->dev, "Manual OTG switch is broken on this "\
					 "SoC, when manual switching from "\
					 "Host to device, DWC3 controller "\
					 "will need to be resetted in order "\
					 "to recover usage of the Host port");

	return dwc3_meson_g12a_otg_mode_set(priv, mode);
}

static enum usb_role dwc3_meson_g12a_role_get(struct usb_role_switch *sw)
{
	struct dwc3_meson_g12a *priv = usb_role_switch_get_drvdata(sw);

	return priv->otg_phy_mode == PHY_MODE_USB_HOST ?
		USB_ROLE_HOST : USB_ROLE_DEVICE;
}

static irqreturn_t dwc3_meson_g12a_irq_thread(int irq, void *data)
{
	struct dwc3_meson_g12a *priv = data;
	enum phy_mode otg_id;

	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(priv->dev, "Failed to switch OTG mode\n");
	}

	regmap_update_bits(priv->usb_glue_regmap, USB_R5,
			   USB_R5_ID_DIG_IRQ, 0);

	return IRQ_HANDLED;
}

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_otg_init(struct platform_device *pdev,
				    struct dwc3_meson_g12a *priv)
{
	enum phy_mode otg_id;
	int ret, irq;
	struct device *dev = &pdev->dev;

	if (!priv->drvdata->otg_switch_supported)
		return 0;

	if (priv->otg_mode == USB_DR_MODE_OTG) {
		/* Ack irq before registering */
		regmap_update_bits(priv->usb_glue_regmap, USB_R5,
				   USB_R5_ID_DIG_IRQ, 0);

		irq = platform_get_irq(pdev, 0);
		ret = devm_request_threaded_irq(&pdev->dev, irq, NULL,
						dwc3_meson_g12a_irq_thread,
						IRQF_ONESHOT, pdev->name, priv);
		if (ret)
			return ret;
	}

	/* Setup OTG mode corresponding to the ID pin */
	if (priv->otg_mode == USB_DR_MODE_OTG) {
		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->switch_desc.driver_data = priv;

	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");

	return 0;
}

static int dwc3_meson_gxl_setup_regmaps(struct dwc3_meson_g12a *priv,
					void __iomem *base)
{
	/* GXL controls the PHY mode in the PHY registers unlike G12A */
	priv->usb_glue_regmap = devm_regmap_init_mmio(priv->dev, base,
					&phy_meson_g12a_usb_glue_regmap_conf);
	if (IS_ERR(priv->usb_glue_regmap))
		return PTR_ERR(priv->usb_glue_regmap);

	return 0;
}

static int dwc3_meson_g12a_setup_regmaps(struct dwc3_meson_g12a *priv,
					 void __iomem *base)
{
	int i;

	priv->usb_glue_regmap = devm_regmap_init_mmio(priv->dev,
					base + G12A_GLUE_OFFSET,
					&phy_meson_g12a_usb_glue_regmap_conf);
	if (IS_ERR(priv->usb_glue_regmap))
		return PTR_ERR(priv->usb_glue_regmap);

	/* Create a regmap for each USB2 PHY control register set */
	for (i = 0; i < priv->usb2_ports; i++) {
		struct regmap_config u2p_regmap_config = {
			.reg_bits = 8,
			.val_bits = 32,
			.reg_stride = 4,
			.max_register = U2P_R1,
		};

		u2p_regmap_config.name = devm_kasprintf(priv->dev, GFP_KERNEL,
							"u2p-%d", i);
		if (!u2p_regmap_config.name)
			return -ENOMEM;

		priv->u2p_regmap[i] = devm_regmap_init_mmio(priv->dev,
						base + (i * U2P_REG_SIZE),
						&u2p_regmap_config);
		if (IS_ERR(priv->u2p_regmap[i]))
			return PTR_ERR(priv->u2p_regmap[i]);
	}

	return 0;
}

static int dwc3_meson_g12a_usb_init(struct dwc3_meson_g12a *priv)
{
	return dwc3_meson_g12a_usb_init_glue(priv, priv->otg_phy_mode);
}

static int dwc3_meson_gxl_usb_init(struct dwc3_meson_g12a *priv)
{
	return dwc3_meson_g12a_usb_init_glue(priv, PHY_MODE_USB_DEVICE);
}

static int dwc3_meson_gxl_usb_post_init(struct dwc3_meson_g12a *priv)
{
	int ret;

	ret = priv->drvdata->set_phy_mode(priv, USB2_OTG_PHY,
					  priv->otg_phy_mode);
	if (ret)
		return ret;

	dwc3_meson_g12a_usb_otg_apply_mode(priv, priv->otg_phy_mode);

	return 0;
}

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;
	int ret, i;

	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
	if (!priv)
		return -ENOMEM;

	base = devm_platform_ioremap_resource(pdev, 0);
	if (IS_ERR(base))
		return PTR_ERR(base);

	priv->drvdata = of_device_get_match_data(&pdev->dev);
	priv->dev = dev;

	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;
	}

	ret = devm_clk_bulk_get(dev,
				priv->drvdata->num_clks,
				priv->drvdata->clks);
	if (ret)
		return ret;

	ret = clk_bulk_prepare_enable(priv->drvdata->num_clks,
				      priv->drvdata->clks);
	if (ret)
		return ret;

	platform_set_drvdata(pdev, priv);

	priv->reset = devm_reset_control_get_shared(dev, NULL);
	if (IS_ERR(priv->reset)) {
		ret = PTR_ERR(priv->reset);
		dev_err(dev, "failed to get device reset, err=%d\n", ret);
		goto err_disable_clks;
	}

	ret = reset_control_reset(priv->reset);
	if (ret)
		goto err_disable_clks;

	ret = dwc3_meson_g12a_get_phys(priv);
	if (ret)
		goto err_disable_clks;

	ret = priv->drvdata->setup_regmaps(priv, base);
	if (ret)
		return ret;

	if (priv->vbus) {
		ret = regulator_enable(priv->vbus);
		if (ret)
			goto err_disable_clks;
	}

	/* Get dr_mode */
	priv->otg_mode = usb_get_dr_mode(dev);

	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;

	ret = priv->drvdata->usb_init(priv);
	if (ret)
		goto err_disable_clks;

	/* Init PHYs */
	for (i = 0 ; i < PHY_COUNT ; ++i) {
		ret = phy_init(priv->phys[i]);
		if (ret)
			goto err_disable_clks;
	}

	/* Set PHY Power */
	for (i = 0 ; i < PHY_COUNT ; ++i) {
		ret = phy_power_on(priv->phys[i]);
		if (ret)
			goto err_phys_exit;
	}

	if (priv->drvdata->usb_post_init) {
		ret = priv->drvdata->usb_post_init(priv);
		if (ret)
			goto err_phys_power;
	}

	ret = of_platform_populate(np, NULL, NULL, dev);
	if (ret)
		goto err_phys_power;

	ret = dwc3_meson_g12a_otg_init(pdev, priv);
	if (ret)
		goto err_phys_power;

	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]);

err_disable_clks:
	clk_bulk_disable_unprepare(priv->drvdata->num_clks,
				   priv->drvdata->clks);

	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;

	if (priv->drvdata->otg_switch_supported)
		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);

	clk_bulk_disable_unprepare(priv->drvdata->num_clks,
				   priv->drvdata->clks);

	return 0;
}

static int __maybe_unused dwc3_meson_g12a_runtime_suspend(struct device *dev)
{
	struct dwc3_meson_g12a	*priv = dev_get_drvdata(dev);

	clk_bulk_disable_unprepare(priv->drvdata->num_clks,
				   priv->drvdata->clks);

	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_bulk_prepare_enable(priv->drvdata->num_clks,
				       priv->drvdata->clks);
}

static int __maybe_unused dwc3_meson_g12a_suspend(struct device *dev)
{
	struct dwc3_meson_g12a *priv = dev_get_drvdata(dev);
	int i, ret;

	if (priv->vbus && priv->otg_phy_mode == PHY_MODE_USB_HOST) {
		ret = regulator_disable(priv->vbus);
		if (ret)
			return ret;
	}

	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);

	ret = priv->drvdata->usb_init(priv);
	if (ret)
		return ret;

	/* 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;
	}

       if (priv->vbus && priv->otg_phy_mode == PHY_MODE_USB_HOST) {
               ret = regulator_enable(priv->vbus);
		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-gxl-usb-ctrl",
		.data = &gxl_drvdata,
	},
	{
		.compatible = "amlogic,meson-gxm-usb-ctrl",
		.data = &gxm_drvdata,
	},
	{
		.compatible = "amlogic,meson-g12a-usb-ctrl",
		.data = &g12a_drvdata,
	},
	{
		.compatible = "amlogic,meson-a1-usb-ctrl",
		.data = &a1_drvdata,
	},
	{ /* 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>");