drivers/usb/mtu3/mtu3_plat.c - arm/linux - Git at Google

 /*
  * Copyright (C) 2016 MediaTek Inc.
  *
  * Author: Chunfeng Yun <chunfeng.yun@mediatek.com>
  *
  * This software is licensed under the terms of the GNU General Public
  * License version 2, as published by the Free Software Foundation, and
  * may be copied, distributed, and modified under those terms.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  */

 #include <linux/clk.h>
 #include <linux/dma-mapping.h>
 #include <linux/iopoll.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/of_address.h>
 #include <linux/of_irq.h>
 #include <linux/pinctrl/consumer.h>
 #include <linux/platform_device.h>

 #include "mtu3.h"
 #include "mtu3_dr.h"

 /* u2-port0 should be powered on and enabled; */
 int ssusb_check_clocks(struct ssusb_mtk *ssusb, u32 ex_clks)
 {
 	void __iomem *ibase = ssusb->ippc_base;
 	u32 value, check_val;
 	int ret;

 	check_val = ex_clks | SSUSB_SYS125_RST_B_STS | SSUSB_SYSPLL_STABLE |
 			SSUSB_REF_RST_B_STS;

 	ret = readl_poll_timeout(ibase + U3D_SSUSB_IP_PW_STS1, value,
 			(check_val == (value & check_val)), 100, 20000);
 	if (ret) {
 		dev_err(ssusb->dev, "clks of sts1 are not stable!\n");
 		return ret;
 	}

 	ret = readl_poll_timeout(ibase + U3D_SSUSB_IP_PW_STS2, value,
 			(value & SSUSB_U2_MAC_SYS_RST_B_STS), 100, 10000);
 	if (ret) {
 		dev_err(ssusb->dev, "mac2 clock is not stable\n");
 		return ret;
 	}

 	return 0;
 }

 static int ssusb_phy_init(struct ssusb_mtk *ssusb)
 {
 	int i;
 	int ret;

 	for (i = 0; i < ssusb->num_phys; i++) {
 		ret = phy_init(ssusb->phys[i]);
 		if (ret)
 			goto exit_phy;
 	}
 	return 0;

 exit_phy:
 	for (; i > 0; i--)
 		phy_exit(ssusb->phys[i - 1]);

 	return ret;
 }

 static int ssusb_phy_exit(struct ssusb_mtk *ssusb)
 {
 	int i;

 	for (i = 0; i < ssusb->num_phys; i++)
 		phy_exit(ssusb->phys[i]);

 	return 0;
 }

 static int ssusb_phy_power_on(struct ssusb_mtk *ssusb)
 {
 	int i;
 	int ret;

 	for (i = 0; i < ssusb->num_phys; i++) {
 		ret = phy_power_on(ssusb->phys[i]);
 		if (ret)
 			goto power_off_phy;
 	}
 	return 0;

 power_off_phy:
 	for (; i > 0; i--)
 		phy_power_off(ssusb->phys[i - 1]);

 	return ret;
 }

 static void ssusb_phy_power_off(struct ssusb_mtk *ssusb)
 {
 	unsigned int i;

 	for (i = 0; i < ssusb->num_phys; i++)
 		phy_power_off(ssusb->phys[i]);
 }

 static int ssusb_rscs_init(struct ssusb_mtk *ssusb)
 {
 	int ret = 0;

 	ret = regulator_enable(ssusb->vusb33);
 	if (ret) {
 		dev_err(ssusb->dev, "failed to enable vusb33\n");
 		goto vusb33_err;
 	}

 	ret = clk_prepare_enable(ssusb->sys_clk);
 	if (ret) {
 		dev_err(ssusb->dev, "failed to enable sys_clk\n");
 		goto sys_clk_err;
 	}

 	ret = clk_prepare_enable(ssusb->ref_clk);
 	if (ret) {
 		dev_err(ssusb->dev, "failed to enable ref_clk\n");
 		goto ref_clk_err;
 	}

 	ret = ssusb_phy_init(ssusb);
 	if (ret) {
 		dev_err(ssusb->dev, "failed to init phy\n");
 		goto phy_init_err;
 	}

 	ret = ssusb_phy_power_on(ssusb);
 	if (ret) {
 		dev_err(ssusb->dev, "failed to power on phy\n");
 		goto phy_err;
 	}

 	return 0;

 phy_err:
 	ssusb_phy_exit(ssusb);
 phy_init_err:
 	clk_disable_unprepare(ssusb->ref_clk);
 ref_clk_err:
 	clk_disable_unprepare(ssusb->sys_clk);
 sys_clk_err:
 	regulator_disable(ssusb->vusb33);
 vusb33_err:

 	return ret;
 }

 static void ssusb_rscs_exit(struct ssusb_mtk *ssusb)
 {
 	clk_disable_unprepare(ssusb->sys_clk);
 	clk_disable_unprepare(ssusb->ref_clk);
 	regulator_disable(ssusb->vusb33);
 	ssusb_phy_power_off(ssusb);
 	ssusb_phy_exit(ssusb);
 }

 static void ssusb_ip_sw_reset(struct ssusb_mtk *ssusb)
 {
 	/* reset whole ip (xhci & u3d) */
 	mtu3_setbits(ssusb->ippc_base, U3D_SSUSB_IP_PW_CTRL0, SSUSB_IP_SW_RST);
 	udelay(1);
 	mtu3_clrbits(ssusb->ippc_base, U3D_SSUSB_IP_PW_CTRL0, SSUSB_IP_SW_RST);
 }

 static int get_iddig_pinctrl(struct ssusb_mtk *ssusb)
 {
 	struct otg_switch_mtk *otg_sx = &ssusb->otg_switch;

 	otg_sx->id_pinctrl = devm_pinctrl_get(ssusb->dev);
 	if (IS_ERR(otg_sx->id_pinctrl)) {
 		dev_err(ssusb->dev, "Cannot find id pinctrl!\n");
 		return PTR_ERR(otg_sx->id_pinctrl);
 	}

 	otg_sx->id_float =
 		pinctrl_lookup_state(otg_sx->id_pinctrl, "id_float");
 	if (IS_ERR(otg_sx->id_float)) {
 		dev_err(ssusb->dev, "Cannot find pinctrl id_float!\n");
 		return PTR_ERR(otg_sx->id_float);
 	}

 	otg_sx->id_ground =
 		pinctrl_lookup_state(otg_sx->id_pinctrl, "id_ground");
 	if (IS_ERR(otg_sx->id_ground)) {
 		dev_err(ssusb->dev, "Cannot find pinctrl id_ground!\n");
 		return PTR_ERR(otg_sx->id_ground);
 	}

 	return 0;
 }

 static int get_ssusb_rscs(struct platform_device *pdev, struct ssusb_mtk *ssusb)
 {
 	struct device_node *node = pdev->dev.of_node;
 	struct otg_switch_mtk *otg_sx = &ssusb->otg_switch;
 	struct device *dev = &pdev->dev;
 	struct regulator *vbus;
 	struct resource *res;
 	int i;
 	int ret;

 	ssusb->vusb33 = devm_regulator_get(&pdev->dev, "vusb33");
 	if (IS_ERR(ssusb->vusb33)) {
 		dev_err(dev, "failed to get vusb33\n");
 		return PTR_ERR(ssusb->vusb33);
 	}

 	ssusb->sys_clk = devm_clk_get(dev, "sys_ck");
 	if (IS_ERR(ssusb->sys_clk)) {
 		dev_err(dev, "failed to get sys clock\n");
 		return PTR_ERR(ssusb->sys_clk);
 	}

 	/*
 	 * reference clock is usually a "fixed-clock", make it optional
 	 * for backward compatibility and ignore the error if it does
 	 * not exist.
 	 */
 	ssusb->ref_clk = devm_clk_get(dev, "ref_ck");
 	if (IS_ERR(ssusb->ref_clk)) {
 		if (PTR_ERR(ssusb->ref_clk) == -EPROBE_DEFER)
 			return -EPROBE_DEFER;

 		ssusb->ref_clk = NULL;
 	}

 	ssusb->num_phys = of_count_phandle_with_args(node,
 			"phys", "#phy-cells");
 	if (ssusb->num_phys > 0) {
 		ssusb->phys = devm_kcalloc(dev, ssusb->num_phys,
 					sizeof(*ssusb->phys), GFP_KERNEL);
 		if (!ssusb->phys)
 			return -ENOMEM;
 	} else {
 		ssusb->num_phys = 0;
 	}

 	for (i = 0; i < ssusb->num_phys; i++) {
 		ssusb->phys[i] = devm_of_phy_get_by_index(dev, node, i);
 		if (IS_ERR(ssusb->phys[i])) {
 			dev_err(dev, "failed to get phy-%d\n", i);
 			return PTR_ERR(ssusb->phys[i]);
 		}
 	}

 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "ippc");
 	ssusb->ippc_base = devm_ioremap_resource(dev, res);
 	if (IS_ERR(ssusb->ippc_base))
 		return PTR_ERR(ssusb->ippc_base);

 	ssusb->dr_mode = usb_get_dr_mode(dev);
 	if (ssusb->dr_mode == USB_DR_MODE_UNKNOWN) {
 		dev_err(dev, "dr_mode is error\n");
 		return -EINVAL;
 	}

 	if (ssusb->dr_mode == USB_DR_MODE_PERIPHERAL)
 		return 0;

 	/* if host role is supported */
 	ret = ssusb_wakeup_of_property_parse(ssusb, node);
 	if (ret)
 		return ret;

 	if (ssusb->dr_mode != USB_DR_MODE_OTG)
 		return 0;

 	/* if dual-role mode is supported */
 	vbus = devm_regulator_get(&pdev->dev, "vbus");
 	if (IS_ERR(vbus)) {
 		dev_err(dev, "failed to get vbus\n");
 		return PTR_ERR(vbus);
 	}
 	otg_sx->vbus = vbus;

 	otg_sx->is_u3_drd = of_property_read_bool(node, "mediatek,usb3-drd");
 	otg_sx->manual_drd_enabled =
 		of_property_read_bool(node, "enable-manual-drd");

 	if (of_property_read_bool(node, "extcon")) {
 		otg_sx->edev = extcon_get_edev_by_phandle(ssusb->dev, 0);
 		if (IS_ERR(otg_sx->edev)) {
 			dev_err(ssusb->dev, "couldn't get extcon device\n");
 			return -EPROBE_DEFER;
 		}
 		if (otg_sx->manual_drd_enabled) {
 			ret = get_iddig_pinctrl(ssusb);
 			if (ret)
 				return ret;
 		}
 	}

 	dev_info(dev, "dr_mode: %d, is_u3_dr: %d\n",
 		ssusb->dr_mode, otg_sx->is_u3_drd);

 	return 0;
 }

 static int mtu3_probe(struct platform_device *pdev)
 {
 	struct device_node *node = pdev->dev.of_node;
 	struct device *dev = &pdev->dev;
 	struct ssusb_mtk *ssusb;
 	int ret = -ENOMEM;

 	/* all elements are set to ZERO as default value */
 	ssusb = devm_kzalloc(dev, sizeof(*ssusb), GFP_KERNEL);
 	if (!ssusb)
 		return -ENOMEM;

 	ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32));
 	if (ret) {
 		dev_err(dev, "No suitable DMA config available\n");
 		return -ENOTSUPP;
 	}

 	platform_set_drvdata(pdev, ssusb);
 	ssusb->dev = dev;

 	ret = get_ssusb_rscs(pdev, ssusb);
 	if (ret)
 		return ret;

 	/* enable power domain */
 	pm_runtime_enable(dev);
 	pm_runtime_get_sync(dev);
 	device_enable_async_suspend(dev);

 	ret = ssusb_rscs_init(ssusb);
 	if (ret)
 		goto comm_init_err;

 	ssusb_ip_sw_reset(ssusb);

 	if (IS_ENABLED(CONFIG_USB_MTU3_HOST))
 		ssusb->dr_mode = USB_DR_MODE_HOST;
 	else if (IS_ENABLED(CONFIG_USB_MTU3_GADGET))
 		ssusb->dr_mode = USB_DR_MODE_PERIPHERAL;

 	/* default as host */
 	ssusb->is_host = !(ssusb->dr_mode == USB_DR_MODE_PERIPHERAL);

 	switch (ssusb->dr_mode) {
 	case USB_DR_MODE_PERIPHERAL:
 		ret = ssusb_gadget_init(ssusb);
 		if (ret) {
 			dev_err(dev, "failed to initialize gadget\n");
 			goto comm_exit;
 		}
 		break;
 	case USB_DR_MODE_HOST:
 		ret = ssusb_host_init(ssusb, node);
 		if (ret) {
 			dev_err(dev, "failed to initialize host\n");
 			goto comm_exit;
 		}
 		break;
 	case USB_DR_MODE_OTG:
 		ret = ssusb_gadget_init(ssusb);
 		if (ret) {
 			dev_err(dev, "failed to initialize gadget\n");
 			goto comm_exit;
 		}

 		ret = ssusb_host_init(ssusb, node);
 		if (ret) {
 			dev_err(dev, "failed to initialize host\n");
 			goto gadget_exit;
 		}

 		ssusb_otg_switch_init(ssusb);
 		break;
 	default:
 		dev_err(dev, "unsupported mode: %d\n", ssusb->dr_mode);
 		ret = -EINVAL;
 		goto comm_exit;
 	}

 	return 0;

 gadget_exit:
 	ssusb_gadget_exit(ssusb);
 comm_exit:
 	ssusb_rscs_exit(ssusb);
 comm_init_err:
 	pm_runtime_put_sync(dev);
 	pm_runtime_disable(dev);

 	return ret;
 }

 static int mtu3_remove(struct platform_device *pdev)
 {
 	struct ssusb_mtk *ssusb = platform_get_drvdata(pdev);

 	switch (ssusb->dr_mode) {
 	case USB_DR_MODE_PERIPHERAL:
 		ssusb_gadget_exit(ssusb);
 		break;
 	case USB_DR_MODE_HOST:
 		ssusb_host_exit(ssusb);
 		break;
 	case USB_DR_MODE_OTG:
 		ssusb_otg_switch_exit(ssusb);
 		ssusb_gadget_exit(ssusb);
 		ssusb_host_exit(ssusb);
 		break;
 	default:
 		return -EINVAL;
 	}

 	ssusb_rscs_exit(ssusb);
 	pm_runtime_put_sync(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);

 	return 0;
 }

 /*
  * when support dual-role mode, we reject suspend when
  * it works as device mode;
  */
 static int __maybe_unused mtu3_suspend(struct device *dev)
 {
 	struct platform_device *pdev = to_platform_device(dev);
 	struct ssusb_mtk *ssusb = platform_get_drvdata(pdev);

 	dev_dbg(dev, "%s\n", __func__);

 	/* REVISIT: disconnect it for only device mode? */
 	if (!ssusb->is_host)
 		return 0;

 	ssusb_host_disable(ssusb, true);
 	ssusb_phy_power_off(ssusb);
 	clk_disable_unprepare(ssusb->sys_clk);
 	clk_disable_unprepare(ssusb->ref_clk);
 	ssusb_wakeup_enable(ssusb);

 	return 0;
 }

 static int __maybe_unused mtu3_resume(struct device *dev)
 {
 	struct platform_device *pdev = to_platform_device(dev);
 	struct ssusb_mtk *ssusb = platform_get_drvdata(pdev);
 	int ret;

 	dev_dbg(dev, "%s\n", __func__);

 	if (!ssusb->is_host)
 		return 0;

 	ssusb_wakeup_disable(ssusb);
 	ret = clk_prepare_enable(ssusb->sys_clk);
 	if (ret)
 		goto err_sys_clk;

 	ret = clk_prepare_enable(ssusb->ref_clk);
 	if (ret)
 		goto err_ref_clk;

 	ret = ssusb_phy_power_on(ssusb);
 	if (ret)
 		goto err_power_on;

 	ssusb_host_enable(ssusb);

 	return 0;

 err_power_on:
 	clk_disable_unprepare(ssusb->ref_clk);
 err_ref_clk:
 	clk_disable_unprepare(ssusb->sys_clk);
 err_sys_clk:
 	return ret;
 }

 static const struct dev_pm_ops mtu3_pm_ops = {
 	SET_SYSTEM_SLEEP_PM_OPS(mtu3_suspend, mtu3_resume)
 };

 #define DEV_PM_OPS (IS_ENABLED(CONFIG_PM) ? &mtu3_pm_ops : NULL)

 #ifdef CONFIG_OF

 static const struct of_device_id mtu3_of_match[] = {
 	{.compatible = "mediatek,mt8173-mtu3",},
 	{.compatible = "mediatek,mtu3",},
 	{},
 };

 MODULE_DEVICE_TABLE(of, mtu3_of_match);

 #endif

 static struct platform_driver mtu3_driver = {
 	.probe = mtu3_probe,
 	.remove = mtu3_remove,
 	.driver = {
 		.name = MTU3_DRIVER_NAME,
 		.pm = DEV_PM_OPS,
 		.of_match_table = of_match_ptr(mtu3_of_match),
 	},
 };
 module_platform_driver(mtu3_driver);

 MODULE_AUTHOR("Chunfeng Yun <chunfeng.yun@mediatek.com>");
 MODULE_LICENSE("GPL v2");
 MODULE_DESCRIPTION("MediaTek USB3 DRD Controller Driver");
	/*
	* Copyright (C) 2016 MediaTek Inc.
	*
	* Author: Chunfeng Yun <chunfeng.yun@mediatek.com>
	*
	* This software is licensed under the terms of the GNU General Public
	* License version 2, as published by the Free Software Foundation, and
	* may be copied, distributed, and modified under those terms.
	*
	* This program is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*
	*/

	#include <linux/clk.h>
	#include <linux/dma-mapping.h>
	#include <linux/iopoll.h>
	#include <linux/kernel.h>
	#include <linux/module.h>
	#include <linux/of_address.h>
	#include <linux/of_irq.h>
	#include <linux/pinctrl/consumer.h>
	#include <linux/platform_device.h>

	#include "mtu3.h"
	#include "mtu3_dr.h"

	/* u2-port0 should be powered on and enabled; */
	int ssusb_check_clocks(struct ssusb_mtk *ssusb, u32 ex_clks)
	{
	void __iomem *ibase = ssusb->ippc_base;
	u32 value, check_val;
	int ret;

	check_val = ex_clks \| SSUSB_SYS125_RST_B_STS \| SSUSB_SYSPLL_STABLE \|
	SSUSB_REF_RST_B_STS;

	ret = readl_poll_timeout(ibase + U3D_SSUSB_IP_PW_STS1, value,
	(check_val == (value & check_val)), 100, 20000);
	if (ret) {
	dev_err(ssusb->dev, "clks of sts1 are not stable!\n");
	return ret;
	}

	ret = readl_poll_timeout(ibase + U3D_SSUSB_IP_PW_STS2, value,
	(value & SSUSB_U2_MAC_SYS_RST_B_STS), 100, 10000);
	if (ret) {
	dev_err(ssusb->dev, "mac2 clock is not stable\n");
	return ret;
	}

	return 0;
	}

	static int ssusb_phy_init(struct ssusb_mtk *ssusb)
	{
	int i;
	int ret;

	for (i = 0; i < ssusb->num_phys; i++) {
	ret = phy_init(ssusb->phys[i]);
	if (ret)
	goto exit_phy;
	}
	return 0;

	exit_phy:
	for (; i > 0; i--)
	phy_exit(ssusb->phys[i - 1]);

	return ret;
	}

	static int ssusb_phy_exit(struct ssusb_mtk *ssusb)
	{
	int i;

	for (i = 0; i < ssusb->num_phys; i++)
	phy_exit(ssusb->phys[i]);

	return 0;
	}

	static int ssusb_phy_power_on(struct ssusb_mtk *ssusb)
	{
	int i;
	int ret;

	for (i = 0; i < ssusb->num_phys; i++) {
	ret = phy_power_on(ssusb->phys[i]);
	if (ret)
	goto power_off_phy;
	}
	return 0;

	power_off_phy:
	for (; i > 0; i--)
	phy_power_off(ssusb->phys[i - 1]);

	return ret;
	}

	static void ssusb_phy_power_off(struct ssusb_mtk *ssusb)
	{
	unsigned int i;

	for (i = 0; i < ssusb->num_phys; i++)
	phy_power_off(ssusb->phys[i]);
	}

	static int ssusb_rscs_init(struct ssusb_mtk *ssusb)
	{
	int ret = 0;

	ret = regulator_enable(ssusb->vusb33);
	if (ret) {
	dev_err(ssusb->dev, "failed to enable vusb33\n");
	goto vusb33_err;
	}

	ret = clk_prepare_enable(ssusb->sys_clk);
	if (ret) {
	dev_err(ssusb->dev, "failed to enable sys_clk\n");
	goto sys_clk_err;
	}

	ret = clk_prepare_enable(ssusb->ref_clk);
	if (ret) {
	dev_err(ssusb->dev, "failed to enable ref_clk\n");
	goto ref_clk_err;
	}

	ret = ssusb_phy_init(ssusb);
	if (ret) {
	dev_err(ssusb->dev, "failed to init phy\n");
	goto phy_init_err;
	}

	ret = ssusb_phy_power_on(ssusb);
	if (ret) {
	dev_err(ssusb->dev, "failed to power on phy\n");
	goto phy_err;
	}

	return 0;

	phy_err:
	ssusb_phy_exit(ssusb);
	phy_init_err:
	clk_disable_unprepare(ssusb->ref_clk);
	ref_clk_err:
	clk_disable_unprepare(ssusb->sys_clk);
	sys_clk_err:
	regulator_disable(ssusb->vusb33);
	vusb33_err:

	return ret;
	}

	static void ssusb_rscs_exit(struct ssusb_mtk *ssusb)
	{
	clk_disable_unprepare(ssusb->sys_clk);
	clk_disable_unprepare(ssusb->ref_clk);
	regulator_disable(ssusb->vusb33);
	ssusb_phy_power_off(ssusb);
	ssusb_phy_exit(ssusb);
	}

	static void ssusb_ip_sw_reset(struct ssusb_mtk *ssusb)
	{
	/* reset whole ip (xhci & u3d) */
	mtu3_setbits(ssusb->ippc_base, U3D_SSUSB_IP_PW_CTRL0, SSUSB_IP_SW_RST);
	udelay(1);
	mtu3_clrbits(ssusb->ippc_base, U3D_SSUSB_IP_PW_CTRL0, SSUSB_IP_SW_RST);
	}

	static int get_iddig_pinctrl(struct ssusb_mtk *ssusb)
	{
	struct otg_switch_mtk *otg_sx = &ssusb->otg_switch;

	otg_sx->id_pinctrl = devm_pinctrl_get(ssusb->dev);
	if (IS_ERR(otg_sx->id_pinctrl)) {
	dev_err(ssusb->dev, "Cannot find id pinctrl!\n");
	return PTR_ERR(otg_sx->id_pinctrl);
	}

	otg_sx->id_float =
	pinctrl_lookup_state(otg_sx->id_pinctrl, "id_float");
	if (IS_ERR(otg_sx->id_float)) {
	dev_err(ssusb->dev, "Cannot find pinctrl id_float!\n");
	return PTR_ERR(otg_sx->id_float);
	}

	otg_sx->id_ground =
	pinctrl_lookup_state(otg_sx->id_pinctrl, "id_ground");
	if (IS_ERR(otg_sx->id_ground)) {
	dev_err(ssusb->dev, "Cannot find pinctrl id_ground!\n");
	return PTR_ERR(otg_sx->id_ground);
	}

	return 0;
	}

	static int get_ssusb_rscs(struct platform_device pdev, struct ssusb_mtk ssusb)
	{
	struct device_node *node = pdev->dev.of_node;
	struct otg_switch_mtk *otg_sx = &ssusb->otg_switch;
	struct device *dev = &pdev->dev;
	struct regulator *vbus;
	struct resource *res;
	int i;
	int ret;

	ssusb->vusb33 = devm_regulator_get(&pdev->dev, "vusb33");
	if (IS_ERR(ssusb->vusb33)) {
	dev_err(dev, "failed to get vusb33\n");
	return PTR_ERR(ssusb->vusb33);
	}

	ssusb->sys_clk = devm_clk_get(dev, "sys_ck");
	if (IS_ERR(ssusb->sys_clk)) {
	dev_err(dev, "failed to get sys clock\n");
	return PTR_ERR(ssusb->sys_clk);
	}

	/*
	* reference clock is usually a "fixed-clock", make it optional
	* for backward compatibility and ignore the error if it does
	* not exist.
	*/
	ssusb->ref_clk = devm_clk_get(dev, "ref_ck");
	if (IS_ERR(ssusb->ref_clk)) {
	if (PTR_ERR(ssusb->ref_clk) == -EPROBE_DEFER)
	return -EPROBE_DEFER;

	ssusb->ref_clk = NULL;
	}

	ssusb->num_phys = of_count_phandle_with_args(node,
	"phys", "#phy-cells");
	if (ssusb->num_phys > 0) {
	ssusb->phys = devm_kcalloc(dev, ssusb->num_phys,
	sizeof(*ssusb->phys), GFP_KERNEL);
	if (!ssusb->phys)
	return -ENOMEM;
	} else {
	ssusb->num_phys = 0;
	}

	for (i = 0; i < ssusb->num_phys; i++) {
	ssusb->phys[i] = devm_of_phy_get_by_index(dev, node, i);
	if (IS_ERR(ssusb->phys[i])) {
	dev_err(dev, "failed to get phy-%d\n", i);
	return PTR_ERR(ssusb->phys[i]);
	}
	}

	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "ippc");
	ssusb->ippc_base = devm_ioremap_resource(dev, res);
	if (IS_ERR(ssusb->ippc_base))
	return PTR_ERR(ssusb->ippc_base);

	ssusb->dr_mode = usb_get_dr_mode(dev);
	if (ssusb->dr_mode == USB_DR_MODE_UNKNOWN) {
	dev_err(dev, "dr_mode is error\n");
	return -EINVAL;
	}

	if (ssusb->dr_mode == USB_DR_MODE_PERIPHERAL)
	return 0;

	/* if host role is supported */
	ret = ssusb_wakeup_of_property_parse(ssusb, node);
	if (ret)
	return ret;

	if (ssusb->dr_mode != USB_DR_MODE_OTG)
	return 0;

	/* if dual-role mode is supported */
	vbus = devm_regulator_get(&pdev->dev, "vbus");
	if (IS_ERR(vbus)) {
	dev_err(dev, "failed to get vbus\n");
	return PTR_ERR(vbus);
	}
	otg_sx->vbus = vbus;

	otg_sx->is_u3_drd = of_property_read_bool(node, "mediatek,usb3-drd");
	otg_sx->manual_drd_enabled =
	of_property_read_bool(node, "enable-manual-drd");

	if (of_property_read_bool(node, "extcon")) {
	otg_sx->edev = extcon_get_edev_by_phandle(ssusb->dev, 0);
	if (IS_ERR(otg_sx->edev)) {
	dev_err(ssusb->dev, "couldn't get extcon device\n");
	return -EPROBE_DEFER;
	}
	if (otg_sx->manual_drd_enabled) {
	ret = get_iddig_pinctrl(ssusb);
	if (ret)
	return ret;
	}
	}

	dev_info(dev, "dr_mode: %d, is_u3_dr: %d\n",
	ssusb->dr_mode, otg_sx->is_u3_drd);

	return 0;
	}

	static int mtu3_probe(struct platform_device *pdev)
	{
	struct device_node *node = pdev->dev.of_node;
	struct device *dev = &pdev->dev;
	struct ssusb_mtk *ssusb;
	int ret = -ENOMEM;

	/* all elements are set to ZERO as default value */
	ssusb = devm_kzalloc(dev, sizeof(*ssusb), GFP_KERNEL);
	if (!ssusb)
	return -ENOMEM;

	ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32));
	if (ret) {
	dev_err(dev, "No suitable DMA config available\n");
	return -ENOTSUPP;
	}

	platform_set_drvdata(pdev, ssusb);
	ssusb->dev = dev;

	ret = get_ssusb_rscs(pdev, ssusb);
	if (ret)
	return ret;

	/* enable power domain */
	pm_runtime_enable(dev);
	pm_runtime_get_sync(dev);
	device_enable_async_suspend(dev);

	ret = ssusb_rscs_init(ssusb);
	if (ret)
	goto comm_init_err;

	ssusb_ip_sw_reset(ssusb);

	if (IS_ENABLED(CONFIG_USB_MTU3_HOST))
	ssusb->dr_mode = USB_DR_MODE_HOST;
	else if (IS_ENABLED(CONFIG_USB_MTU3_GADGET))
	ssusb->dr_mode = USB_DR_MODE_PERIPHERAL;

	/* default as host */
	ssusb->is_host = !(ssusb->dr_mode == USB_DR_MODE_PERIPHERAL);

	switch (ssusb->dr_mode) {
	case USB_DR_MODE_PERIPHERAL:
	ret = ssusb_gadget_init(ssusb);
	if (ret) {
	dev_err(dev, "failed to initialize gadget\n");
	goto comm_exit;
	}
	break;
	case USB_DR_MODE_HOST:
	ret = ssusb_host_init(ssusb, node);
	if (ret) {
	dev_err(dev, "failed to initialize host\n");
	goto comm_exit;
	}
	break;
	case USB_DR_MODE_OTG:
	ret = ssusb_gadget_init(ssusb);
	if (ret) {
	dev_err(dev, "failed to initialize gadget\n");
	goto comm_exit;
	}

	ret = ssusb_host_init(ssusb, node);
	if (ret) {
	dev_err(dev, "failed to initialize host\n");
	goto gadget_exit;
	}

	ssusb_otg_switch_init(ssusb);
	break;
	default:
	dev_err(dev, "unsupported mode: %d\n", ssusb->dr_mode);
	ret = -EINVAL;
	goto comm_exit;
	}

	return 0;

	gadget_exit:
	ssusb_gadget_exit(ssusb);
	comm_exit:
	ssusb_rscs_exit(ssusb);
	comm_init_err:
	pm_runtime_put_sync(dev);
	pm_runtime_disable(dev);

	return ret;
	}

	static int mtu3_remove(struct platform_device *pdev)
	{
	struct ssusb_mtk *ssusb = platform_get_drvdata(pdev);

	switch (ssusb->dr_mode) {
	case USB_DR_MODE_PERIPHERAL:
	ssusb_gadget_exit(ssusb);
	break;
	case USB_DR_MODE_HOST:
	ssusb_host_exit(ssusb);
	break;
	case USB_DR_MODE_OTG:
	ssusb_otg_switch_exit(ssusb);
	ssusb_gadget_exit(ssusb);
	ssusb_host_exit(ssusb);
	break;
	default:
	return -EINVAL;
	}

	ssusb_rscs_exit(ssusb);
	pm_runtime_put_sync(&pdev->dev);
	pm_runtime_disable(&pdev->dev);

	return 0;
	}

	/*
	* when support dual-role mode, we reject suspend when
	* it works as device mode;
	*/
	static int __maybe_unused mtu3_suspend(struct device *dev)
	{
	struct platform_device *pdev = to_platform_device(dev);
	struct ssusb_mtk *ssusb = platform_get_drvdata(pdev);

	dev_dbg(dev, "%s\n", __func__);

	/* REVISIT: disconnect it for only device mode? */
	if (!ssusb->is_host)
	return 0;

	ssusb_host_disable(ssusb, true);
	ssusb_phy_power_off(ssusb);
	clk_disable_unprepare(ssusb->sys_clk);
	clk_disable_unprepare(ssusb->ref_clk);
	ssusb_wakeup_enable(ssusb);

	return 0;
	}

	static int __maybe_unused mtu3_resume(struct device *dev)
	{
	struct platform_device *pdev = to_platform_device(dev);
	struct ssusb_mtk *ssusb = platform_get_drvdata(pdev);
	int ret;

	dev_dbg(dev, "%s\n", __func__);

	if (!ssusb->is_host)
	return 0;

	ssusb_wakeup_disable(ssusb);
	ret = clk_prepare_enable(ssusb->sys_clk);
	if (ret)
	goto err_sys_clk;

	ret = clk_prepare_enable(ssusb->ref_clk);
	if (ret)
	goto err_ref_clk;

	ret = ssusb_phy_power_on(ssusb);
	if (ret)
	goto err_power_on;

	ssusb_host_enable(ssusb);

	return 0;

	err_power_on:
	clk_disable_unprepare(ssusb->ref_clk);
	err_ref_clk:
	clk_disable_unprepare(ssusb->sys_clk);
	err_sys_clk:
	return ret;
	}

	static const struct dev_pm_ops mtu3_pm_ops = {
	SET_SYSTEM_SLEEP_PM_OPS(mtu3_suspend, mtu3_resume)
	};

	#define DEV_PM_OPS (IS_ENABLED(CONFIG_PM) ? &mtu3_pm_ops : NULL)

	#ifdef CONFIG_OF

	static const struct of_device_id mtu3_of_match[] = {
	{.compatible = "mediatek,mt8173-mtu3",},
	{.compatible = "mediatek,mtu3",},
	{},
	};

	MODULE_DEVICE_TABLE(of, mtu3_of_match);

	#endif

	static struct platform_driver mtu3_driver = {
	.probe = mtu3_probe,
	.remove = mtu3_remove,
	.driver = {
	.name = MTU3_DRIVER_NAME,
	.pm = DEV_PM_OPS,
	.of_match_table = of_match_ptr(mtu3_of_match),
	},
	};
	module_platform_driver(mtu3_driver);

	MODULE_AUTHOR("Chunfeng Yun <chunfeng.yun@mediatek.com>");
	MODULE_LICENSE("GPL v2");
	MODULE_DESCRIPTION("MediaTek USB3 DRD Controller Driver");