// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2018, The Linux Foundation. All rights reserved.
 *
 * Inspired by dwc3-of-simple.c
 */

#include <linux/cleanup.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/clk.h>
#include <linux/irq.h>
#include <linux/of_clk.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/extcon.h>
#include <linux/interconnect.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/phy/phy.h>
#include <linux/usb/of.h>
#include <linux/reset.h>
#include <linux/iopoll.h>
#include <linux/usb/hcd.h>
#include <linux/usb.h>
#include "core.h"

/* USB QSCRATCH Hardware registers */
#define QSCRATCH_HS_PHY_CTRL			0x10
#define UTMI_OTG_VBUS_VALID			BIT(20)
#define SW_SESSVLD_SEL				BIT(28)

#define QSCRATCH_SS_PHY_CTRL			0x30
#define LANE0_PWR_PRESENT			BIT(24)

#define QSCRATCH_GENERAL_CFG			0x08
#define PIPE_UTMI_CLK_SEL			BIT(0)
#define PIPE3_PHYSTATUS_SW			BIT(3)
#define PIPE_UTMI_CLK_DIS			BIT(8)

#define PWR_EVNT_LPM_IN_L2_MASK			BIT(4)
#define PWR_EVNT_LPM_OUT_L2_MASK		BIT(5)

#define SDM845_QSCRATCH_BASE_OFFSET		0xf8800
#define SDM845_QSCRATCH_SIZE			0x400
#define SDM845_DWC3_CORE_SIZE			0xcd00

/* Interconnect path bandwidths in MBps */
#define USB_MEMORY_AVG_HS_BW MBps_to_icc(240)
#define USB_MEMORY_PEAK_HS_BW MBps_to_icc(700)
#define USB_MEMORY_AVG_SS_BW  MBps_to_icc(1000)
#define USB_MEMORY_PEAK_SS_BW MBps_to_icc(2500)
#define APPS_USB_AVG_BW 0
#define APPS_USB_PEAK_BW MBps_to_icc(40)

/* Qualcomm SoCs with multiport support has up to 4 ports */
#define DWC3_QCOM_MAX_PORTS	4

static const u32 pwr_evnt_irq_stat_reg[DWC3_QCOM_MAX_PORTS] = {
	0x58,
	0x1dc,
	0x228,
	0x238,
};

struct dwc3_qcom_port {
	int			qusb2_phy_irq;
	int			dp_hs_phy_irq;
	int			dm_hs_phy_irq;
	int			ss_phy_irq;
	enum usb_device_speed	usb2_speed;
};

struct dwc3_qcom {
	struct device		*dev;
	void __iomem		*qscratch_base;
	struct platform_device	*dwc3;
	struct clk		**clks;
	int			num_clocks;
	struct reset_control	*resets;
	struct dwc3_qcom_port	ports[DWC3_QCOM_MAX_PORTS];
	u8			num_ports;

	struct extcon_dev	*edev;
	struct extcon_dev	*host_edev;
	struct notifier_block	vbus_nb;
	struct notifier_block	host_nb;

	enum usb_dr_mode	mode;
	bool			is_suspended;
	bool			pm_suspended;
	struct icc_path		*icc_path_ddr;
	struct icc_path		*icc_path_apps;
};

static inline void dwc3_qcom_setbits(void __iomem *base, u32 offset, u32 val)
{
	u32 reg;

	reg = readl(base + offset);
	reg |= val;
	writel(reg, base + offset);

	/* ensure that above write is through */
	readl(base + offset);
}

static inline void dwc3_qcom_clrbits(void __iomem *base, u32 offset, u32 val)
{
	u32 reg;

	reg = readl(base + offset);
	reg &= ~val;
	writel(reg, base + offset);

	/* ensure that above write is through */
	readl(base + offset);
}

static void dwc3_qcom_vbus_override_enable(struct dwc3_qcom *qcom, bool enable)
{
	if (enable) {
		dwc3_qcom_setbits(qcom->qscratch_base, QSCRATCH_SS_PHY_CTRL,
				  LANE0_PWR_PRESENT);
		dwc3_qcom_setbits(qcom->qscratch_base, QSCRATCH_HS_PHY_CTRL,
				  UTMI_OTG_VBUS_VALID | SW_SESSVLD_SEL);
	} else {
		dwc3_qcom_clrbits(qcom->qscratch_base, QSCRATCH_SS_PHY_CTRL,
				  LANE0_PWR_PRESENT);
		dwc3_qcom_clrbits(qcom->qscratch_base, QSCRATCH_HS_PHY_CTRL,
				  UTMI_OTG_VBUS_VALID | SW_SESSVLD_SEL);
	}
}

static int dwc3_qcom_vbus_notifier(struct notifier_block *nb,
				   unsigned long event, void *ptr)
{
	struct dwc3_qcom *qcom = container_of(nb, struct dwc3_qcom, vbus_nb);

	/* enable vbus override for device mode */
	dwc3_qcom_vbus_override_enable(qcom, event);
	qcom->mode = event ? USB_DR_MODE_PERIPHERAL : USB_DR_MODE_HOST;

	return NOTIFY_DONE;
}

static int dwc3_qcom_host_notifier(struct notifier_block *nb,
				   unsigned long event, void *ptr)
{
	struct dwc3_qcom *qcom = container_of(nb, struct dwc3_qcom, host_nb);

	/* disable vbus override in host mode */
	dwc3_qcom_vbus_override_enable(qcom, !event);
	qcom->mode = event ? USB_DR_MODE_HOST : USB_DR_MODE_PERIPHERAL;

	return NOTIFY_DONE;
}

static int dwc3_qcom_register_extcon(struct dwc3_qcom *qcom)
{
	struct device		*dev = qcom->dev;
	struct extcon_dev	*host_edev;
	int			ret;

	if (!of_property_read_bool(dev->of_node, "extcon"))
		return 0;

	qcom->edev = extcon_get_edev_by_phandle(dev, 0);
	if (IS_ERR(qcom->edev))
		return dev_err_probe(dev, PTR_ERR(qcom->edev),
				     "Failed to get extcon\n");

	qcom->vbus_nb.notifier_call = dwc3_qcom_vbus_notifier;

	qcom->host_edev = extcon_get_edev_by_phandle(dev, 1);
	if (IS_ERR(qcom->host_edev))
		qcom->host_edev = NULL;

	ret = devm_extcon_register_notifier(dev, qcom->edev, EXTCON_USB,
					    &qcom->vbus_nb);
	if (ret < 0) {
		dev_err(dev, "VBUS notifier register failed\n");
		return ret;
	}

	if (qcom->host_edev)
		host_edev = qcom->host_edev;
	else
		host_edev = qcom->edev;

	qcom->host_nb.notifier_call = dwc3_qcom_host_notifier;
	ret = devm_extcon_register_notifier(dev, host_edev, EXTCON_USB_HOST,
					    &qcom->host_nb);
	if (ret < 0) {
		dev_err(dev, "Host notifier register failed\n");
		return ret;
	}

	/* Update initial VBUS override based on extcon state */
	if (extcon_get_state(qcom->edev, EXTCON_USB) ||
	    !extcon_get_state(host_edev, EXTCON_USB_HOST))
		dwc3_qcom_vbus_notifier(&qcom->vbus_nb, true, qcom->edev);
	else
		dwc3_qcom_vbus_notifier(&qcom->vbus_nb, false, qcom->edev);

	return 0;
}

static int dwc3_qcom_interconnect_enable(struct dwc3_qcom *qcom)
{
	int ret;

	ret = icc_enable(qcom->icc_path_ddr);
	if (ret)
		return ret;

	ret = icc_enable(qcom->icc_path_apps);
	if (ret)
		icc_disable(qcom->icc_path_ddr);

	return ret;
}

static int dwc3_qcom_interconnect_disable(struct dwc3_qcom *qcom)
{
	int ret;

	ret = icc_disable(qcom->icc_path_ddr);
	if (ret)
		return ret;

	ret = icc_disable(qcom->icc_path_apps);
	if (ret)
		icc_enable(qcom->icc_path_ddr);

	return ret;
}

/**
 * dwc3_qcom_interconnect_init() - Get interconnect path handles
 * and set bandwidth.
 * @qcom:			Pointer to the concerned usb core.
 *
 */
static int dwc3_qcom_interconnect_init(struct dwc3_qcom *qcom)
{
	enum usb_device_speed max_speed;
	struct device *dev = qcom->dev;
	int ret;

	qcom->icc_path_ddr = of_icc_get(dev, "usb-ddr");
	if (IS_ERR(qcom->icc_path_ddr)) {
		return dev_err_probe(dev, PTR_ERR(qcom->icc_path_ddr),
				     "failed to get usb-ddr path\n");
	}

	qcom->icc_path_apps = of_icc_get(dev, "apps-usb");
	if (IS_ERR(qcom->icc_path_apps)) {
		ret = dev_err_probe(dev, PTR_ERR(qcom->icc_path_apps),
				    "failed to get apps-usb path\n");
		goto put_path_ddr;
	}

	max_speed = usb_get_maximum_speed(&qcom->dwc3->dev);
	if (max_speed >= USB_SPEED_SUPER || max_speed == USB_SPEED_UNKNOWN) {
		ret = icc_set_bw(qcom->icc_path_ddr,
				USB_MEMORY_AVG_SS_BW, USB_MEMORY_PEAK_SS_BW);
	} else {
		ret = icc_set_bw(qcom->icc_path_ddr,
				USB_MEMORY_AVG_HS_BW, USB_MEMORY_PEAK_HS_BW);
	}
	if (ret) {
		dev_err(dev, "failed to set bandwidth for usb-ddr path: %d\n", ret);
		goto put_path_apps;
	}

	ret = icc_set_bw(qcom->icc_path_apps, APPS_USB_AVG_BW, APPS_USB_PEAK_BW);
	if (ret) {
		dev_err(dev, "failed to set bandwidth for apps-usb path: %d\n", ret);
		goto put_path_apps;
	}

	return 0;

put_path_apps:
	icc_put(qcom->icc_path_apps);
put_path_ddr:
	icc_put(qcom->icc_path_ddr);
	return ret;
}

/**
 * dwc3_qcom_interconnect_exit() - Release interconnect path handles
 * @qcom:			Pointer to the concerned usb core.
 *
 * This function is used to release interconnect path handle.
 */
static void dwc3_qcom_interconnect_exit(struct dwc3_qcom *qcom)
{
	icc_put(qcom->icc_path_ddr);
	icc_put(qcom->icc_path_apps);
}

/* Only usable in contexts where the role can not change. */
static bool dwc3_qcom_is_host(struct dwc3_qcom *qcom)
{
	struct dwc3 *dwc;

	/*
	 * FIXME: Fix this layering violation.
	 */
	dwc = platform_get_drvdata(qcom->dwc3);

	/* Core driver may not have probed yet. */
	if (!dwc)
		return false;

	return dwc->xhci;
}

static enum usb_device_speed dwc3_qcom_read_usb2_speed(struct dwc3_qcom *qcom, int port_index)
{
	struct dwc3 *dwc = platform_get_drvdata(qcom->dwc3);
	struct usb_device *udev;
	struct usb_hcd __maybe_unused *hcd;

	/*
	 * FIXME: Fix this layering violation.
	 */
	hcd = platform_get_drvdata(dwc->xhci);

#ifdef CONFIG_USB
	udev = usb_hub_find_child(hcd->self.root_hub, port_index + 1);
#else
	udev = NULL;
#endif
	if (!udev)
		return USB_SPEED_UNKNOWN;

	return udev->speed;
}

static void dwc3_qcom_enable_wakeup_irq(int irq, unsigned int polarity)
{
	if (!irq)
		return;

	if (polarity)
		irq_set_irq_type(irq, polarity);

	enable_irq(irq);
	enable_irq_wake(irq);
}

static void dwc3_qcom_disable_wakeup_irq(int irq)
{
	if (!irq)
		return;

	disable_irq_wake(irq);
	disable_irq_nosync(irq);
}

static void dwc3_qcom_disable_port_interrupts(struct dwc3_qcom_port *port)
{
	dwc3_qcom_disable_wakeup_irq(port->qusb2_phy_irq);

	if (port->usb2_speed == USB_SPEED_LOW) {
		dwc3_qcom_disable_wakeup_irq(port->dm_hs_phy_irq);
	} else if ((port->usb2_speed == USB_SPEED_HIGH) ||
			(port->usb2_speed == USB_SPEED_FULL)) {
		dwc3_qcom_disable_wakeup_irq(port->dp_hs_phy_irq);
	} else {
		dwc3_qcom_disable_wakeup_irq(port->dp_hs_phy_irq);
		dwc3_qcom_disable_wakeup_irq(port->dm_hs_phy_irq);
	}

	dwc3_qcom_disable_wakeup_irq(port->ss_phy_irq);
}

static void dwc3_qcom_enable_port_interrupts(struct dwc3_qcom_port *port)
{
	dwc3_qcom_enable_wakeup_irq(port->qusb2_phy_irq, 0);

	/*
	 * Configure DP/DM line interrupts based on the USB2 device attached to
	 * the root hub port. When HS/FS device is connected, configure the DP line
	 * as falling edge to detect both disconnect and remote wakeup scenarios. When
	 * LS device is connected, configure DM line as falling edge to detect both
	 * disconnect and remote wakeup. When no device is connected, configure both
	 * DP and DM lines as rising edge to detect HS/HS/LS device connect scenario.
	 */

	if (port->usb2_speed == USB_SPEED_LOW) {
		dwc3_qcom_enable_wakeup_irq(port->dm_hs_phy_irq,
					    IRQ_TYPE_EDGE_FALLING);
	} else if ((port->usb2_speed == USB_SPEED_HIGH) ||
			(port->usb2_speed == USB_SPEED_FULL)) {
		dwc3_qcom_enable_wakeup_irq(port->dp_hs_phy_irq,
					    IRQ_TYPE_EDGE_FALLING);
	} else {
		dwc3_qcom_enable_wakeup_irq(port->dp_hs_phy_irq,
					    IRQ_TYPE_EDGE_RISING);
		dwc3_qcom_enable_wakeup_irq(port->dm_hs_phy_irq,
					    IRQ_TYPE_EDGE_RISING);
	}

	dwc3_qcom_enable_wakeup_irq(port->ss_phy_irq, 0);
}

static void dwc3_qcom_disable_interrupts(struct dwc3_qcom *qcom)
{
	int i;

	for (i = 0; i < qcom->num_ports; i++)
		dwc3_qcom_disable_port_interrupts(&qcom->ports[i]);
}

static void dwc3_qcom_enable_interrupts(struct dwc3_qcom *qcom)
{
	int i;

	for (i = 0; i < qcom->num_ports; i++)
		dwc3_qcom_enable_port_interrupts(&qcom->ports[i]);
}

static int dwc3_qcom_suspend(struct dwc3_qcom *qcom, bool wakeup)
{
	u32 val;
	int i, ret;

	if (qcom->is_suspended)
		return 0;

	for (i = 0; i < qcom->num_ports; i++) {
		val = readl(qcom->qscratch_base + pwr_evnt_irq_stat_reg[i]);
		if (!(val & PWR_EVNT_LPM_IN_L2_MASK))
			dev_err(qcom->dev, "port-%d HS-PHY not in L2\n", i + 1);
	}

	for (i = qcom->num_clocks - 1; i >= 0; i--)
		clk_disable_unprepare(qcom->clks[i]);

	ret = dwc3_qcom_interconnect_disable(qcom);
	if (ret)
		dev_warn(qcom->dev, "failed to disable interconnect: %d\n", ret);

	/*
	 * The role is stable during suspend as role switching is done from a
	 * freezable workqueue.
	 */
	if (dwc3_qcom_is_host(qcom) && wakeup) {
		for (i = 0; i < qcom->num_ports; i++)
			qcom->ports[i].usb2_speed = dwc3_qcom_read_usb2_speed(qcom, i);
		dwc3_qcom_enable_interrupts(qcom);
	}

	qcom->is_suspended = true;

	return 0;
}

static int dwc3_qcom_resume(struct dwc3_qcom *qcom, bool wakeup)
{
	int ret;
	int i;

	if (!qcom->is_suspended)
		return 0;

	if (dwc3_qcom_is_host(qcom) && wakeup)
		dwc3_qcom_disable_interrupts(qcom);

	for (i = 0; i < qcom->num_clocks; i++) {
		ret = clk_prepare_enable(qcom->clks[i]);
		if (ret < 0) {
			while (--i >= 0)
				clk_disable_unprepare(qcom->clks[i]);
			return ret;
		}
	}

	ret = dwc3_qcom_interconnect_enable(qcom);
	if (ret)
		dev_warn(qcom->dev, "failed to enable interconnect: %d\n", ret);

	/* Clear existing events from PHY related to L2 in/out */
	for (i = 0; i < qcom->num_ports; i++) {
		dwc3_qcom_setbits(qcom->qscratch_base,
				  pwr_evnt_irq_stat_reg[i],
				  PWR_EVNT_LPM_IN_L2_MASK | PWR_EVNT_LPM_OUT_L2_MASK);
	}

	qcom->is_suspended = false;

	return 0;
}

static irqreturn_t qcom_dwc3_resume_irq(int irq, void *data)
{
	struct dwc3_qcom *qcom = data;
	struct dwc3	*dwc = platform_get_drvdata(qcom->dwc3);

	/* If pm_suspended then let pm_resume take care of resuming h/w */
	if (qcom->pm_suspended)
		return IRQ_HANDLED;

	/*
	 * This is safe as role switching is done from a freezable workqueue
	 * and the wakeup interrupts are disabled as part of resume.
	 */
	if (dwc3_qcom_is_host(qcom))
		pm_runtime_resume(&dwc->xhci->dev);

	return IRQ_HANDLED;
}

static void dwc3_qcom_select_utmi_clk(struct dwc3_qcom *qcom)
{
	/* Configure dwc3 to use UTMI clock as PIPE clock not present */
	dwc3_qcom_setbits(qcom->qscratch_base, QSCRATCH_GENERAL_CFG,
			  PIPE_UTMI_CLK_DIS);

	usleep_range(100, 1000);

	dwc3_qcom_setbits(qcom->qscratch_base, QSCRATCH_GENERAL_CFG,
			  PIPE_UTMI_CLK_SEL | PIPE3_PHYSTATUS_SW);

	usleep_range(100, 1000);

	dwc3_qcom_clrbits(qcom->qscratch_base, QSCRATCH_GENERAL_CFG,
			  PIPE_UTMI_CLK_DIS);
}

static int dwc3_qcom_request_irq(struct dwc3_qcom *qcom, int irq,
				 const char *name)
{
	int ret;

	/* Keep wakeup interrupts disabled until suspend */
	ret = devm_request_threaded_irq(qcom->dev, irq, NULL,
					qcom_dwc3_resume_irq,
					IRQF_ONESHOT | IRQF_NO_AUTOEN,
					name, qcom);
	if (ret)
		dev_err(qcom->dev, "failed to request irq %s: %d\n", name, ret);

	return ret;
}

static int dwc3_qcom_setup_port_irq(struct platform_device *pdev, int port_index, bool is_multiport)
{
	struct dwc3_qcom *qcom = platform_get_drvdata(pdev);
	const char *irq_name;
	int irq;
	int ret;

	if (is_multiport)
		irq_name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "dp_hs_phy_%d", port_index + 1);
	else
		irq_name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "dp_hs_phy_irq");
	if (!irq_name)
		return -ENOMEM;

	irq = platform_get_irq_byname_optional(pdev, irq_name);
	if (irq > 0) {
		ret = dwc3_qcom_request_irq(qcom, irq, irq_name);
		if (ret)
			return ret;
		qcom->ports[port_index].dp_hs_phy_irq = irq;
	}

	if (is_multiport)
		irq_name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "dm_hs_phy_%d", port_index + 1);
	else
		irq_name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "dm_hs_phy_irq");
	if (!irq_name)
		return -ENOMEM;

	irq = platform_get_irq_byname_optional(pdev, irq_name);
	if (irq > 0) {
		ret = dwc3_qcom_request_irq(qcom, irq, irq_name);
		if (ret)
			return ret;
		qcom->ports[port_index].dm_hs_phy_irq = irq;
	}

	if (is_multiport)
		irq_name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "ss_phy_%d", port_index + 1);
	else
		irq_name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "ss_phy_irq");
	if (!irq_name)
		return -ENOMEM;

	irq = platform_get_irq_byname_optional(pdev, irq_name);
	if (irq > 0) {
		ret = dwc3_qcom_request_irq(qcom, irq, irq_name);
		if (ret)
			return ret;
		qcom->ports[port_index].ss_phy_irq = irq;
	}

	if (is_multiport)
		return 0;

	irq = platform_get_irq_byname_optional(pdev, "qusb2_phy");
	if (irq > 0) {
		ret = dwc3_qcom_request_irq(qcom, irq, "qusb2_phy");
		if (ret)
			return ret;
		qcom->ports[port_index].qusb2_phy_irq = irq;
	}

	return 0;
}

static int dwc3_qcom_find_num_ports(struct platform_device *pdev)
{
	char irq_name[14];
	int port_num;
	int irq;

	irq = platform_get_irq_byname_optional(pdev, "dp_hs_phy_1");
	if (irq <= 0)
		return 1;

	for (port_num = 2; port_num <= DWC3_QCOM_MAX_PORTS; port_num++) {
		sprintf(irq_name, "dp_hs_phy_%d", port_num);

		irq = platform_get_irq_byname_optional(pdev, irq_name);
		if (irq <= 0)
			return port_num - 1;
	}

	return DWC3_QCOM_MAX_PORTS;
}

static int dwc3_qcom_setup_irq(struct platform_device *pdev)
{
	struct dwc3_qcom *qcom = platform_get_drvdata(pdev);
	bool is_multiport;
	int ret;
	int i;

	qcom->num_ports = dwc3_qcom_find_num_ports(pdev);
	is_multiport = (qcom->num_ports > 1);

	for (i = 0; i < qcom->num_ports; i++) {
		ret = dwc3_qcom_setup_port_irq(pdev, i, is_multiport);
		if (ret)
			return ret;
	}

	return 0;
}

static int dwc3_qcom_clk_init(struct dwc3_qcom *qcom, int count)
{
	struct device		*dev = qcom->dev;
	struct device_node	*np = dev->of_node;
	int			i;

	if (!np || !count)
		return 0;

	if (count < 0)
		return count;

	qcom->num_clocks = count;

	qcom->clks = devm_kcalloc(dev, qcom->num_clocks,
				  sizeof(struct clk *), GFP_KERNEL);
	if (!qcom->clks)
		return -ENOMEM;

	for (i = 0; i < qcom->num_clocks; i++) {
		struct clk	*clk;
		int		ret;

		clk = of_clk_get(np, i);
		if (IS_ERR(clk)) {
			while (--i >= 0)
				clk_put(qcom->clks[i]);
			return PTR_ERR(clk);
		}

		ret = clk_prepare_enable(clk);
		if (ret < 0) {
			while (--i >= 0) {
				clk_disable_unprepare(qcom->clks[i]);
				clk_put(qcom->clks[i]);
			}
			clk_put(clk);

			return ret;
		}

		qcom->clks[i] = clk;
	}

	return 0;
}

static int dwc3_qcom_of_register_core(struct platform_device *pdev)
{
	struct dwc3_qcom	*qcom = platform_get_drvdata(pdev);
	struct device_node	*np = pdev->dev.of_node;
	struct device		*dev = &pdev->dev;
	int			ret;

	struct device_node *dwc3_np __free(device_node) = of_get_compatible_child(np,
										  "snps,dwc3");
	if (!dwc3_np) {
		dev_err(dev, "failed to find dwc3 core child\n");
		return -ENODEV;
	}

	ret = of_platform_populate(np, NULL, NULL, dev);
	if (ret) {
		dev_err(dev, "failed to register dwc3 core - %d\n", ret);
		return ret;
	}

	qcom->dwc3 = of_find_device_by_node(dwc3_np);
	if (!qcom->dwc3) {
		ret = -ENODEV;
		dev_err(dev, "failed to get dwc3 platform device\n");
		of_platform_depopulate(dev);
	}

	return ret;
}

static int dwc3_qcom_probe(struct platform_device *pdev)
{
	struct device_node	*np = pdev->dev.of_node;
	struct device		*dev = &pdev->dev;
	struct dwc3_qcom	*qcom;
	int			ret, i;
	bool			ignore_pipe_clk;
	bool			wakeup_source;

	qcom = devm_kzalloc(&pdev->dev, sizeof(*qcom), GFP_KERNEL);
	if (!qcom)
		return -ENOMEM;

	platform_set_drvdata(pdev, qcom);
	qcom->dev = &pdev->dev;

	qcom->resets = devm_reset_control_array_get_optional_exclusive(dev);
	if (IS_ERR(qcom->resets)) {
		return dev_err_probe(&pdev->dev, PTR_ERR(qcom->resets),
				     "failed to get resets\n");
	}

	ret = reset_control_assert(qcom->resets);
	if (ret) {
		dev_err(&pdev->dev, "failed to assert resets, err=%d\n", ret);
		return ret;
	}

	usleep_range(10, 1000);

	ret = reset_control_deassert(qcom->resets);
	if (ret) {
		dev_err(&pdev->dev, "failed to deassert resets, err=%d\n", ret);
		goto reset_assert;
	}

	ret = dwc3_qcom_clk_init(qcom, of_clk_get_parent_count(np));
	if (ret) {
		dev_err_probe(dev, ret, "failed to get clocks\n");
		goto reset_assert;
	}

	qcom->qscratch_base = devm_platform_ioremap_resource(pdev, 0);
	if (IS_ERR(qcom->qscratch_base)) {
		ret = PTR_ERR(qcom->qscratch_base);
		goto clk_disable;
	}

	ret = dwc3_qcom_setup_irq(pdev);
	if (ret) {
		dev_err(dev, "failed to setup IRQs, err=%d\n", ret);
		goto clk_disable;
	}

	/*
	 * Disable pipe_clk requirement if specified. Used when dwc3
	 * operates without SSPHY and only HS/FS/LS modes are supported.
	 */
	ignore_pipe_clk = device_property_read_bool(dev,
				"qcom,select-utmi-as-pipe-clk");
	if (ignore_pipe_clk)
		dwc3_qcom_select_utmi_clk(qcom);

	ret = dwc3_qcom_of_register_core(pdev);
	if (ret) {
		dev_err(dev, "failed to register DWC3 Core, err=%d\n", ret);
		goto clk_disable;
	}

	ret = dwc3_qcom_interconnect_init(qcom);
	if (ret)
		goto depopulate;

	qcom->mode = usb_get_dr_mode(&qcom->dwc3->dev);

	/* enable vbus override for device mode */
	if (qcom->mode != USB_DR_MODE_HOST)
		dwc3_qcom_vbus_override_enable(qcom, true);

	/* register extcon to override sw_vbus on Vbus change later */
	ret = dwc3_qcom_register_extcon(qcom);
	if (ret)
		goto interconnect_exit;

	wakeup_source = of_property_read_bool(dev->of_node, "wakeup-source");
	device_init_wakeup(&pdev->dev, wakeup_source);
	device_init_wakeup(&qcom->dwc3->dev, wakeup_source);

	qcom->is_suspended = false;
	pm_runtime_set_active(dev);
	pm_runtime_enable(dev);
	pm_runtime_forbid(dev);

	return 0;

interconnect_exit:
	dwc3_qcom_interconnect_exit(qcom);
depopulate:
	of_platform_depopulate(&pdev->dev);
	platform_device_put(qcom->dwc3);
clk_disable:
	for (i = qcom->num_clocks - 1; i >= 0; i--) {
		clk_disable_unprepare(qcom->clks[i]);
		clk_put(qcom->clks[i]);
	}
reset_assert:
	reset_control_assert(qcom->resets);

	return ret;
}

static void dwc3_qcom_remove(struct platform_device *pdev)
{
	struct dwc3_qcom *qcom = platform_get_drvdata(pdev);
	struct device *dev = &pdev->dev;
	int i;

	of_platform_depopulate(&pdev->dev);
	platform_device_put(qcom->dwc3);

	for (i = qcom->num_clocks - 1; i >= 0; i--) {
		clk_disable_unprepare(qcom->clks[i]);
		clk_put(qcom->clks[i]);
	}
	qcom->num_clocks = 0;

	dwc3_qcom_interconnect_exit(qcom);
	reset_control_assert(qcom->resets);

	pm_runtime_allow(dev);
	pm_runtime_disable(dev);
}

static int __maybe_unused dwc3_qcom_pm_suspend(struct device *dev)
{
	struct dwc3_qcom *qcom = dev_get_drvdata(dev);
	bool wakeup = device_may_wakeup(dev);
	int ret;

	ret = dwc3_qcom_suspend(qcom, wakeup);
	if (ret)
		return ret;

	qcom->pm_suspended = true;

	return 0;
}

static int __maybe_unused dwc3_qcom_pm_resume(struct device *dev)
{
	struct dwc3_qcom *qcom = dev_get_drvdata(dev);
	bool wakeup = device_may_wakeup(dev);
	int ret;

	ret = dwc3_qcom_resume(qcom, wakeup);
	if (ret)
		return ret;

	qcom->pm_suspended = false;

	return 0;
}

static int __maybe_unused dwc3_qcom_runtime_suspend(struct device *dev)
{
	struct dwc3_qcom *qcom = dev_get_drvdata(dev);

	return dwc3_qcom_suspend(qcom, true);
}

static int __maybe_unused dwc3_qcom_runtime_resume(struct device *dev)
{
	struct dwc3_qcom *qcom = dev_get_drvdata(dev);

	return dwc3_qcom_resume(qcom, true);
}

static const struct dev_pm_ops dwc3_qcom_dev_pm_ops = {
	SET_SYSTEM_SLEEP_PM_OPS(dwc3_qcom_pm_suspend, dwc3_qcom_pm_resume)
	SET_RUNTIME_PM_OPS(dwc3_qcom_runtime_suspend, dwc3_qcom_runtime_resume,
			   NULL)
};

static const struct of_device_id dwc3_qcom_of_match[] = {
	{ .compatible = "qcom,dwc3" },
	{ }
};
MODULE_DEVICE_TABLE(of, dwc3_qcom_of_match);

static struct platform_driver dwc3_qcom_driver = {
	.probe		= dwc3_qcom_probe,
	.remove_new	= dwc3_qcom_remove,
	.driver		= {
		.name	= "dwc3-qcom",
		.pm	= &dwc3_qcom_dev_pm_ops,
		.of_match_table	= dwc3_qcom_of_match,
	},
};

module_platform_driver(dwc3_qcom_driver);

MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("DesignWare DWC3 QCOM Glue Driver");