v4.19.13 snapshot.
diff --git a/drivers/usb/misc/usb3503.c b/drivers/usb/misc/usb3503.c
new file mode 100644
index 0000000..f723f7b
--- /dev/null
+++ b/drivers/usb/misc/usb3503.c
@@ -0,0 +1,449 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Driver for SMSC USB3503 USB 2.0 hub controller driver
+ *
+ * Copyright (c) 2012-2013 Dongjin Kim (tobetter@gmail.com)
+ */
+
+#include <linux/clk.h>
+#include <linux/i2c.h>
+#include <linux/gpio.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/of_gpio.h>
+#include <linux/platform_device.h>
+#include <linux/platform_data/usb3503.h>
+#include <linux/regmap.h>
+
+#define USB3503_VIDL		0x00
+#define USB3503_VIDM		0x01
+#define USB3503_PIDL		0x02
+#define USB3503_PIDM		0x03
+#define USB3503_DIDL		0x04
+#define USB3503_DIDM		0x05
+
+#define USB3503_CFG1		0x06
+#define USB3503_SELF_BUS_PWR	(1 << 7)
+
+#define USB3503_CFG2		0x07
+#define USB3503_CFG3		0x08
+#define USB3503_NRD		0x09
+
+#define USB3503_PDS		0x0a
+
+#define USB3503_SP_ILOCK	0xe7
+#define USB3503_SPILOCK_CONNECT	(1 << 1)
+#define USB3503_SPILOCK_CONFIG	(1 << 0)
+
+#define USB3503_CFGP		0xee
+#define USB3503_CLKSUSP		(1 << 7)
+
+#define USB3503_RESET		0xff
+
+struct usb3503 {
+	enum usb3503_mode	mode;
+	struct regmap		*regmap;
+	struct device		*dev;
+	struct clk		*clk;
+	u8	port_off_mask;
+	int	gpio_intn;
+	int	gpio_reset;
+	int	gpio_connect;
+	bool	secondary_ref_clk;
+};
+
+static int usb3503_reset(struct usb3503 *hub, int state)
+{
+	if (!state && gpio_is_valid(hub->gpio_connect))
+		gpio_set_value_cansleep(hub->gpio_connect, 0);
+
+	if (gpio_is_valid(hub->gpio_reset))
+		gpio_set_value_cansleep(hub->gpio_reset, state);
+
+	/* Wait T_HUBINIT == 4ms for hub logic to stabilize */
+	if (state)
+		usleep_range(4000, 10000);
+
+	return 0;
+}
+
+static int usb3503_connect(struct usb3503 *hub)
+{
+	struct device *dev = hub->dev;
+	int err;
+
+	usb3503_reset(hub, 1);
+
+	if (hub->regmap) {
+		/* SP_ILOCK: set connect_n, config_n for config */
+		err = regmap_write(hub->regmap, USB3503_SP_ILOCK,
+			   (USB3503_SPILOCK_CONNECT
+				 | USB3503_SPILOCK_CONFIG));
+		if (err < 0) {
+			dev_err(dev, "SP_ILOCK failed (%d)\n", err);
+			return err;
+		}
+
+		/* PDS : Set the ports which are disabled in self-powered mode. */
+		if (hub->port_off_mask) {
+			err = regmap_update_bits(hub->regmap, USB3503_PDS,
+					hub->port_off_mask,
+					hub->port_off_mask);
+			if (err < 0) {
+				dev_err(dev, "PDS failed (%d)\n", err);
+				return err;
+			}
+		}
+
+		/* CFG1 : Set SELF_BUS_PWR, this enables self-powered operation. */
+		err = regmap_update_bits(hub->regmap, USB3503_CFG1,
+					 USB3503_SELF_BUS_PWR,
+					 USB3503_SELF_BUS_PWR);
+		if (err < 0) {
+			dev_err(dev, "CFG1 failed (%d)\n", err);
+			return err;
+		}
+
+		/* SP_LOCK: clear connect_n, config_n for hub connect */
+		err = regmap_update_bits(hub->regmap, USB3503_SP_ILOCK,
+					 (USB3503_SPILOCK_CONNECT
+					  | USB3503_SPILOCK_CONFIG), 0);
+		if (err < 0) {
+			dev_err(dev, "SP_ILOCK failed (%d)\n", err);
+			return err;
+		}
+	}
+
+	if (gpio_is_valid(hub->gpio_connect))
+		gpio_set_value_cansleep(hub->gpio_connect, 1);
+
+	hub->mode = USB3503_MODE_HUB;
+	dev_info(dev, "switched to HUB mode\n");
+
+	return 0;
+}
+
+static int usb3503_switch_mode(struct usb3503 *hub, enum usb3503_mode mode)
+{
+	struct device *dev = hub->dev;
+	int err = 0;
+
+	switch (mode) {
+	case USB3503_MODE_HUB:
+		err = usb3503_connect(hub);
+		break;
+
+	case USB3503_MODE_STANDBY:
+		usb3503_reset(hub, 0);
+		dev_info(dev, "switched to STANDBY mode\n");
+		break;
+
+	default:
+		dev_err(dev, "unknown mode is requested\n");
+		err = -EINVAL;
+		break;
+	}
+
+	return err;
+}
+
+static const struct regmap_config usb3503_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+
+	.max_register = USB3503_RESET,
+};
+
+static int usb3503_probe(struct usb3503 *hub)
+{
+	struct device *dev = hub->dev;
+	struct usb3503_platform_data *pdata = dev_get_platdata(dev);
+	struct device_node *np = dev->of_node;
+	int err;
+	u32 mode = USB3503_MODE_HUB;
+	const u32 *property;
+	int len;
+
+	if (pdata) {
+		hub->port_off_mask	= pdata->port_off_mask;
+		hub->gpio_intn		= pdata->gpio_intn;
+		hub->gpio_connect	= pdata->gpio_connect;
+		hub->gpio_reset		= pdata->gpio_reset;
+		hub->mode		= pdata->initial_mode;
+	} else if (np) {
+		struct clk *clk;
+		u32 rate = 0;
+		hub->port_off_mask = 0;
+
+		if (!of_property_read_u32(np, "refclk-frequency", &rate)) {
+			switch (rate) {
+			case 38400000:
+			case 26000000:
+			case 19200000:
+			case 12000000:
+				hub->secondary_ref_clk = 0;
+				break;
+			case 24000000:
+			case 27000000:
+			case 25000000:
+			case 50000000:
+				hub->secondary_ref_clk = 1;
+				break;
+			default:
+				dev_err(dev,
+					"unsupported reference clock rate (%d)\n",
+					(int) rate);
+				return -EINVAL;
+			}
+		}
+
+		clk = devm_clk_get(dev, "refclk");
+		if (IS_ERR(clk) && PTR_ERR(clk) != -ENOENT) {
+			dev_err(dev, "unable to request refclk (%ld)\n",
+					PTR_ERR(clk));
+			return PTR_ERR(clk);
+		}
+
+		if (!IS_ERR(clk)) {
+			hub->clk = clk;
+
+			if (rate != 0) {
+				err = clk_set_rate(hub->clk, rate);
+				if (err) {
+					dev_err(dev,
+						"unable to set reference clock rate to %d\n",
+						(int) rate);
+					return err;
+				}
+			}
+
+			err = clk_prepare_enable(hub->clk);
+			if (err) {
+				dev_err(dev,
+					"unable to enable reference clock\n");
+				return err;
+			}
+		}
+
+		property = of_get_property(np, "disabled-ports", &len);
+		if (property && (len / sizeof(u32)) > 0) {
+			int i;
+			for (i = 0; i < len / sizeof(u32); i++) {
+				u32 port = be32_to_cpu(property[i]);
+				if ((1 <= port) && (port <= 3))
+					hub->port_off_mask |= (1 << port);
+			}
+		}
+
+		hub->gpio_intn	= of_get_named_gpio(np, "intn-gpios", 0);
+		if (hub->gpio_intn == -EPROBE_DEFER)
+			return -EPROBE_DEFER;
+		hub->gpio_connect = of_get_named_gpio(np, "connect-gpios", 0);
+		if (hub->gpio_connect == -EPROBE_DEFER)
+			return -EPROBE_DEFER;
+		hub->gpio_reset = of_get_named_gpio(np, "reset-gpios", 0);
+		if (hub->gpio_reset == -EPROBE_DEFER)
+			return -EPROBE_DEFER;
+		of_property_read_u32(np, "initial-mode", &mode);
+		hub->mode = mode;
+	}
+
+	if (hub->port_off_mask && !hub->regmap)
+		dev_err(dev, "Ports disabled with no control interface\n");
+
+	if (gpio_is_valid(hub->gpio_intn)) {
+		int val = hub->secondary_ref_clk ? GPIOF_OUT_INIT_LOW :
+						   GPIOF_OUT_INIT_HIGH;
+		err = devm_gpio_request_one(dev, hub->gpio_intn, val,
+					    "usb3503 intn");
+		if (err) {
+			dev_err(dev,
+				"unable to request GPIO %d as interrupt pin (%d)\n",
+				hub->gpio_intn, err);
+			return err;
+		}
+	}
+
+	if (gpio_is_valid(hub->gpio_connect)) {
+		err = devm_gpio_request_one(dev, hub->gpio_connect,
+				GPIOF_OUT_INIT_LOW, "usb3503 connect");
+		if (err) {
+			dev_err(dev,
+				"unable to request GPIO %d as connect pin (%d)\n",
+				hub->gpio_connect, err);
+			return err;
+		}
+	}
+
+	if (gpio_is_valid(hub->gpio_reset)) {
+		err = devm_gpio_request_one(dev, hub->gpio_reset,
+				GPIOF_OUT_INIT_LOW, "usb3503 reset");
+		/* Datasheet defines a hardware reset to be at least 100us */
+		usleep_range(100, 10000);
+		if (err) {
+			dev_err(dev,
+				"unable to request GPIO %d as reset pin (%d)\n",
+				hub->gpio_reset, err);
+			return err;
+		}
+	}
+
+	usb3503_switch_mode(hub, hub->mode);
+
+	dev_info(dev, "%s: probed in %s mode\n", __func__,
+			(hub->mode == USB3503_MODE_HUB) ? "hub" : "standby");
+
+	return 0;
+}
+
+static int usb3503_i2c_probe(struct i2c_client *i2c,
+			     const struct i2c_device_id *id)
+{
+	struct usb3503 *hub;
+	int err;
+
+	hub = devm_kzalloc(&i2c->dev, sizeof(struct usb3503), GFP_KERNEL);
+	if (!hub)
+		return -ENOMEM;
+
+	i2c_set_clientdata(i2c, hub);
+	hub->regmap = devm_regmap_init_i2c(i2c, &usb3503_regmap_config);
+	if (IS_ERR(hub->regmap)) {
+		err = PTR_ERR(hub->regmap);
+		dev_err(&i2c->dev, "Failed to initialise regmap: %d\n", err);
+		return err;
+	}
+	hub->dev = &i2c->dev;
+
+	return usb3503_probe(hub);
+}
+
+static int usb3503_i2c_remove(struct i2c_client *i2c)
+{
+	struct usb3503 *hub;
+
+	hub = i2c_get_clientdata(i2c);
+	if (hub->clk)
+		clk_disable_unprepare(hub->clk);
+
+	return 0;
+}
+
+static int usb3503_platform_probe(struct platform_device *pdev)
+{
+	struct usb3503 *hub;
+
+	hub = devm_kzalloc(&pdev->dev, sizeof(struct usb3503), GFP_KERNEL);
+	if (!hub)
+		return -ENOMEM;
+	hub->dev = &pdev->dev;
+	platform_set_drvdata(pdev, hub);
+
+	return usb3503_probe(hub);
+}
+
+static int usb3503_platform_remove(struct platform_device *pdev)
+{
+	struct usb3503 *hub;
+
+	hub = platform_get_drvdata(pdev);
+	if (hub->clk)
+		clk_disable_unprepare(hub->clk);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int usb3503_i2c_suspend(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct usb3503 *hub = i2c_get_clientdata(client);
+
+	usb3503_switch_mode(hub, USB3503_MODE_STANDBY);
+
+	if (hub->clk)
+		clk_disable_unprepare(hub->clk);
+
+	return 0;
+}
+
+static int usb3503_i2c_resume(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct usb3503 *hub = i2c_get_clientdata(client);
+
+	if (hub->clk)
+		clk_prepare_enable(hub->clk);
+
+	usb3503_switch_mode(hub, hub->mode);
+
+	return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(usb3503_i2c_pm_ops, usb3503_i2c_suspend,
+		usb3503_i2c_resume);
+
+static const struct i2c_device_id usb3503_id[] = {
+	{ USB3503_I2C_NAME, 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, usb3503_id);
+
+#ifdef CONFIG_OF
+static const struct of_device_id usb3503_of_match[] = {
+	{ .compatible = "smsc,usb3503", },
+	{ .compatible = "smsc,usb3503a", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, usb3503_of_match);
+#endif
+
+static struct i2c_driver usb3503_i2c_driver = {
+	.driver = {
+		.name = USB3503_I2C_NAME,
+		.pm = &usb3503_i2c_pm_ops,
+		.of_match_table = of_match_ptr(usb3503_of_match),
+	},
+	.probe		= usb3503_i2c_probe,
+	.remove		= usb3503_i2c_remove,
+	.id_table	= usb3503_id,
+};
+
+static struct platform_driver usb3503_platform_driver = {
+	.driver = {
+		.name = USB3503_I2C_NAME,
+		.of_match_table = of_match_ptr(usb3503_of_match),
+	},
+	.probe		= usb3503_platform_probe,
+	.remove		= usb3503_platform_remove,
+};
+
+static int __init usb3503_init(void)
+{
+	int err;
+
+	err = i2c_add_driver(&usb3503_i2c_driver);
+	if (err != 0)
+		pr_err("usb3503: Failed to register I2C driver: %d\n", err);
+
+	err = platform_driver_register(&usb3503_platform_driver);
+	if (err != 0)
+		pr_err("usb3503: Failed to register platform driver: %d\n",
+		       err);
+
+	return 0;
+}
+module_init(usb3503_init);
+
+static void __exit usb3503_exit(void)
+{
+	platform_driver_unregister(&usb3503_platform_driver);
+	i2c_del_driver(&usb3503_i2c_driver);
+}
+module_exit(usb3503_exit);
+
+MODULE_AUTHOR("Dongjin Kim <tobetter@gmail.com>");
+MODULE_DESCRIPTION("USB3503 USB HUB driver");
+MODULE_LICENSE("GPL");