v4.19.13 snapshot.
diff --git a/drivers/usb/misc/usb4604.c b/drivers/usb/misc/usb4604.c
new file mode 100644
index 0000000..1b4de65
--- /dev/null
+++ b/drivers/usb/misc/usb4604.c
@@ -0,0 +1,166 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Driver for SMSC USB4604 USB HSIC 4-port 2.0 hub controller driver
+ * Based on usb3503 driver
+ *
+ * Copyright (c) 2012-2013 Dongjin Kim (tobetter@gmail.com)
+ * Copyright (c) 2016 Linaro Ltd.
+ */
+
+#include <linux/i2c.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/gpio/consumer.h>
+
+enum usb4604_mode {
+ USB4604_MODE_UNKNOWN,
+ USB4604_MODE_HUB,
+ USB4604_MODE_STANDBY,
+};
+
+struct usb4604 {
+ enum usb4604_mode mode;
+ struct device *dev;
+ struct gpio_desc *gpio_reset;
+};
+
+static void usb4604_reset(struct usb4604 *hub, int state)
+{
+ gpiod_set_value_cansleep(hub->gpio_reset, state);
+
+ /* Wait for i2c logic to come up */
+ if (state)
+ msleep(250);
+}
+
+static int usb4604_connect(struct usb4604 *hub)
+{
+ struct device *dev = hub->dev;
+ struct i2c_client *client = to_i2c_client(dev);
+ int err;
+ u8 connect_cmd[] = { 0xaa, 0x55, 0x00 };
+
+ usb4604_reset(hub, 1);
+
+ err = i2c_master_send(client, connect_cmd, ARRAY_SIZE(connect_cmd));
+ if (err < 0) {
+ usb4604_reset(hub, 0);
+ return err;
+ }
+
+ hub->mode = USB4604_MODE_HUB;
+ dev_dbg(dev, "switched to HUB mode\n");
+
+ return 0;
+}
+
+static int usb4604_switch_mode(struct usb4604 *hub, enum usb4604_mode mode)
+{
+ struct device *dev = hub->dev;
+ int err = 0;
+
+ switch (mode) {
+ case USB4604_MODE_HUB:
+ err = usb4604_connect(hub);
+ break;
+
+ case USB4604_MODE_STANDBY:
+ usb4604_reset(hub, 0);
+ dev_dbg(dev, "switched to STANDBY mode\n");
+ break;
+
+ default:
+ dev_err(dev, "unknown mode is requested\n");
+ err = -EINVAL;
+ break;
+ }
+
+ return err;
+}
+
+static int usb4604_probe(struct usb4604 *hub)
+{
+ struct device *dev = hub->dev;
+ struct device_node *np = dev->of_node;
+ struct gpio_desc *gpio;
+ u32 mode = USB4604_MODE_HUB;
+
+ gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
+ if (IS_ERR(gpio))
+ return PTR_ERR(gpio);
+ hub->gpio_reset = gpio;
+
+ if (of_property_read_u32(np, "initial-mode", &hub->mode))
+ hub->mode = mode;
+
+ return usb4604_switch_mode(hub, hub->mode);
+}
+
+static int usb4604_i2c_probe(struct i2c_client *i2c,
+ const struct i2c_device_id *id)
+{
+ struct usb4604 *hub;
+
+ hub = devm_kzalloc(&i2c->dev, sizeof(*hub), GFP_KERNEL);
+ if (!hub)
+ return -ENOMEM;
+
+ i2c_set_clientdata(i2c, hub);
+ hub->dev = &i2c->dev;
+
+ return usb4604_probe(hub);
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int usb4604_i2c_suspend(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct usb4604 *hub = i2c_get_clientdata(client);
+
+ usb4604_switch_mode(hub, USB4604_MODE_STANDBY);
+
+ return 0;
+}
+
+static int usb4604_i2c_resume(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct usb4604 *hub = i2c_get_clientdata(client);
+
+ usb4604_switch_mode(hub, hub->mode);
+
+ return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(usb4604_i2c_pm_ops, usb4604_i2c_suspend,
+ usb4604_i2c_resume);
+
+static const struct i2c_device_id usb4604_id[] = {
+ { "usb4604", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, usb4604_id);
+
+#ifdef CONFIG_OF
+static const struct of_device_id usb4604_of_match[] = {
+ { .compatible = "smsc,usb4604" },
+ {}
+};
+MODULE_DEVICE_TABLE(of, usb4604_of_match);
+#endif
+
+static struct i2c_driver usb4604_i2c_driver = {
+ .driver = {
+ .name = "usb4604",
+ .pm = &usb4604_i2c_pm_ops,
+ .of_match_table = of_match_ptr(usb4604_of_match),
+ },
+ .probe = usb4604_i2c_probe,
+ .id_table = usb4604_id,
+};
+module_i2c_driver(usb4604_i2c_driver);
+
+MODULE_DESCRIPTION("USB4604 USB HUB driver");
+MODULE_LICENSE("GPL v2");