Merge tag 'usb-for-v5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb into usb-next

Felipe writes:

USB: changes for v5.7 merge window

Lots of changes on dwc3 this time, most of them from Thinh fixing a
bunch of really old mishaps on the driver.

DWC2 got support for STM32MP15 and a couple RockChip SoCs while DWC3
learned about Amlogic A1 family.

Apart from these, we have a few spelling fixes and other minor
non-critical fixes all over the place.

Signed-off-by: Felipe Balbi <balbi@kernel.org>

* tag 'usb-for-v5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb: (41 commits)
  dt-bindings: usb: add documentation for aspeed usb-vhub
  ARM: dts: aspeed-g4: add vhub port and endpoint properties
  ARM: dts: aspeed-g5: add vhub port and endpoint properties
  ARM: dts: aspeed-g6: add usb functions
  usb: gadget: aspeed: add ast2600 vhub support
  usb: gadget: aspeed: read vhub properties from device tree
  usb: gadget: aspeed: support per-vhub usb descriptors
  usb: gadget: f_phonet: Replace zero-length array with flexible-array member
  usb: gadget: composite: Inform controller driver of self-powered
  usb: gadget: amd5536udc: fix spelling mistake "reserverd" -> "reserved"
  udc: s3c-hsudc: Silence warning about supplies during deferred probe
  usb: dwc2: Silence warning about supplies during deferred probe
  dt-bindings: usb: dwc2: add compatible property for rk3368 usb
  dt-bindings: usb: dwc2: add compatible property for rk3328 usb
  usb: gadget: add raw-gadget interface
  usb: dwc2: Implement set_selfpowered()
  usb: dwc3: qcom: Replace <linux/clk-provider.h> by <linux/of_clk.h>
  usb: dwc3: core: don't do suspend for device mode if already suspended
  usb: dwc3: Rework resets initialization to be more flexible
  usb: dwc3: Rework clock initialization to be more flexible
  ...

14 files changed, 2581 insertions, 75 deletions

diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c
index 223f72d4d9ed..cb4950cf1cdc 100644
--- a/drivers/usb/gadget/composite.c
+++ b/drivers/usb/gadget/composite.c
@@ -861,6 +861,11 @@ static int set_config(struct usb_composite_dev *cdev,
 	else
 		power = min(power, 900U);
 done:
+	if (power <= USB_SELF_POWER_VBUS_MAX_DRAW)
+		usb_gadget_set_selfpowered(gadget);
+	else
+		usb_gadget_clear_selfpowered(gadget);
+
 	usb_gadget_vbus_draw(gadget, power);
 	if (result >= 0 && cdev->delayed_status)
 		result = USB_GADGET_DELAYED_STATUS;
@@ -2279,6 +2284,7 @@ void composite_suspend(struct usb_gadget *gadget)
 
 	cdev->suspended = 1;
 
+	usb_gadget_set_selfpowered(gadget);
 	usb_gadget_vbus_draw(gadget, 2);
 }
 
@@ -2307,6 +2313,9 @@ void composite_resume(struct usb_gadget *gadget)
 		else
 			maxpower = min(maxpower, 900U);
 
+		if (maxpower > USB_SELF_POWER_VBUS_MAX_DRAW)
+			usb_gadget_clear_selfpowered(gadget);
+
 		usb_gadget_vbus_draw(gadget, maxpower);
 	}
 
diff --git a/drivers/usb/gadget/legacy/Kconfig b/drivers/usb/gadget/legacy/Kconfig
index 6e7e1a9202e6..a7064e21d9f2 100644
--- a/drivers/usb/gadget/legacy/Kconfig
+++ b/drivers/usb/gadget/legacy/Kconfig
@@ -516,4 +516,15 @@ config USB_G_WEBCAM
 	  Say "y" to link the driver statically, or "m" to build a
 	  dynamically linked module called "g_webcam".
 
+config USB_RAW_GADGET
+	tristate "USB Raw Gadget"
+	help
+	  USB Raw Gadget is a kernel module that provides a userspace interface
+	  for the USB Gadget subsystem. Essentially it allows to emulate USB
+	  devices from userspace. See Documentation/usb/raw-gadget.rst for
+	  details.
+
+	  Say "y" to link the driver statically, or "m" to build a
+	  dynamically linked module called "raw_gadget".
+
 endchoice
diff --git a/drivers/usb/gadget/legacy/Makefile b/drivers/usb/gadget/legacy/Makefile
index abd0c3e66a05..4d864bf82799 100644
--- a/drivers/usb/gadget/legacy/Makefile
+++ b/drivers/usb/gadget/legacy/Makefile
@@ -43,3 +43,4 @@ obj-$(CONFIG_USB_G_WEBCAM)	+= g_webcam.o
 obj-$(CONFIG_USB_G_NCM)		+= g_ncm.o
 obj-$(CONFIG_USB_G_ACM_MS)	+= g_acm_ms.o
 obj-$(CONFIG_USB_GADGET_TARGET)	+= tcm_usb_gadget.o
+obj-$(CONFIG_USB_RAW_GADGET)	+= raw_gadget.o
diff --git a/drivers/usb/gadget/legacy/raw_gadget.c b/drivers/usb/gadget/legacy/raw_gadget.c
new file mode 100644
index 000000000000..76406343fbe5
--- /dev/null
+++ b/drivers/usb/gadget/legacy/raw_gadget.c
@@ -0,0 +1,1078 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * USB Raw Gadget driver.
+ * See Documentation/usb/raw-gadget.rst for more details.
+ *
+ * Andrey Konovalov <andreyknvl@gmail.com>
+ */
+
+#include <linux/compiler.h>
+#include <linux/debugfs.h>
+#include <linux/delay.h>
+#include <linux/kref.h>
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+#include <linux/semaphore.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+#include <linux/wait.h>
+
+#include <linux/usb.h>
+#include <linux/usb/ch9.h>
+#include <linux/usb/ch11.h>
+#include <linux/usb/gadget.h>
+
+#include <uapi/linux/usb/raw_gadget.h>
+
+#define	DRIVER_DESC "USB Raw Gadget"
+#define DRIVER_NAME "raw-gadget"
+
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_AUTHOR("Andrey Konovalov");
+MODULE_LICENSE("GPL");
+
+/*----------------------------------------------------------------------*/
+
+#define RAW_EVENT_QUEUE_SIZE	16
+
+struct raw_event_queue {
+	/* See the comment in raw_event_queue_fetch() for locking details. */
+	spinlock_t		lock;
+	struct semaphore	sema;
+	struct usb_raw_event	*events[RAW_EVENT_QUEUE_SIZE];
+	int			size;
+};
+
+static void raw_event_queue_init(struct raw_event_queue *queue)
+{
+	spin_lock_init(&queue->lock);
+	sema_init(&queue->sema, 0);
+	queue->size = 0;
+}
+
+static int raw_event_queue_add(struct raw_event_queue *queue,
+	enum usb_raw_event_type type, size_t length, const void *data)
+{
+	unsigned long flags;
+	struct usb_raw_event *event;
+
+	spin_lock_irqsave(&queue->lock, flags);
+	if (WARN_ON(queue->size >= RAW_EVENT_QUEUE_SIZE)) {
+		spin_unlock_irqrestore(&queue->lock, flags);
+		return -ENOMEM;
+	}
+	event = kmalloc(sizeof(*event) + length, GFP_ATOMIC);
+	if (!event) {
+		spin_unlock_irqrestore(&queue->lock, flags);
+		return -ENOMEM;
+	}
+	event->type = type;
+	event->length = length;
+	if (event->length)
+		memcpy(&event->data[0], data, length);
+	queue->events[queue->size] = event;
+	queue->size++;
+	up(&queue->sema);
+	spin_unlock_irqrestore(&queue->lock, flags);
+	return 0;
+}
+
+static struct usb_raw_event *raw_event_queue_fetch(
+				struct raw_event_queue *queue)
+{
+	unsigned long flags;
+	struct usb_raw_event *event;
+
+	/*
+	 * This function can be called concurrently. We first check that
+	 * there's at least one event queued by decrementing the semaphore,
+	 * and then take the lock to protect queue struct fields.
+	 */
+	if (down_interruptible(&queue->sema))
+		return NULL;
+	spin_lock_irqsave(&queue->lock, flags);
+	if (WARN_ON(!queue->size))
+		return NULL;
+	event = queue->events[0];
+	queue->size--;
+	memmove(&queue->events[0], &queue->events[1],
+			queue->size * sizeof(queue->events[0]));
+	spin_unlock_irqrestore(&queue->lock, flags);
+	return event;
+}
+
+static void raw_event_queue_destroy(struct raw_event_queue *queue)
+{
+	int i;
+
+	for (i = 0; i < queue->size; i++)
+		kfree(queue->events[i]);
+	queue->size = 0;
+}
+
+/*----------------------------------------------------------------------*/
+
+struct raw_dev;
+
+#define USB_RAW_MAX_ENDPOINTS 32
+
+enum ep_state {
+	STATE_EP_DISABLED,
+	STATE_EP_ENABLED,
+};
+
+struct raw_ep {
+	struct raw_dev		*dev;
+	enum ep_state		state;
+	struct usb_ep		*ep;
+	struct usb_request	*req;
+	bool			urb_queued;
+	bool			disabling;
+	ssize_t			status;
+};
+
+enum dev_state {
+	STATE_DEV_INVALID = 0,
+	STATE_DEV_OPENED,
+	STATE_DEV_INITIALIZED,
+	STATE_DEV_RUNNING,
+	STATE_DEV_CLOSED,
+	STATE_DEV_FAILED
+};
+
+struct raw_dev {
+	struct kref			count;
+	spinlock_t			lock;
+
+	const char			*udc_name;
+	struct usb_gadget_driver	driver;
+
+	/* Reference to misc device: */
+	struct device			*dev;
+
+	/* Protected by lock: */
+	enum dev_state			state;
+	bool				gadget_registered;
+	struct usb_gadget		*gadget;
+	struct usb_request		*req;
+	bool				ep0_in_pending;
+	bool				ep0_out_pending;
+	bool				ep0_urb_queued;
+	ssize_t				ep0_status;
+	struct raw_ep			eps[USB_RAW_MAX_ENDPOINTS];
+
+	struct completion		ep0_done;
+	struct raw_event_queue		queue;
+};
+
+static struct raw_dev *dev_new(void)
+{
+	struct raw_dev *dev;
+
+	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
+	if (!dev)
+		return NULL;
+	/* Matches kref_put() in raw_release(). */
+	kref_init(&dev->count);
+	spin_lock_init(&dev->lock);
+	init_completion(&dev->ep0_done);
+	raw_event_queue_init(&dev->queue);
+	return dev;
+}
+
+static void dev_free(struct kref *kref)
+{
+	struct raw_dev *dev = container_of(kref, struct raw_dev, count);
+	int i;
+
+	kfree(dev->udc_name);
+	kfree(dev->driver.udc_name);
+	if (dev->req) {
+		if (dev->ep0_urb_queued)
+			usb_ep_dequeue(dev->gadget->ep0, dev->req);
+		usb_ep_free_request(dev->gadget->ep0, dev->req);
+	}
+	raw_event_queue_destroy(&dev->queue);
+	for (i = 0; i < USB_RAW_MAX_ENDPOINTS; i++) {
+		if (dev->eps[i].state != STATE_EP_ENABLED)
+			continue;
+		usb_ep_disable(dev->eps[i].ep);
+		usb_ep_free_request(dev->eps[i].ep, dev->eps[i].req);
+		kfree(dev->eps[i].ep->desc);
+		dev->eps[i].state = STATE_EP_DISABLED;
+	}
+	kfree(dev);
+}
+
+/*----------------------------------------------------------------------*/
+
+static int raw_queue_event(struct raw_dev *dev,
+	enum usb_raw_event_type type, size_t length, const void *data)
+{
+	int ret = 0;
+	unsigned long flags;
+
+	ret = raw_event_queue_add(&dev->queue, type, length, data);
+	if (ret < 0) {
+		spin_lock_irqsave(&dev->lock, flags);
+		dev->state = STATE_DEV_FAILED;
+		spin_unlock_irqrestore(&dev->lock, flags);
+	}
+	return ret;
+}
+
+static void gadget_ep0_complete(struct usb_ep *ep, struct usb_request *req)
+{
+	struct raw_dev *dev = req->context;
+	unsigned long flags;
+
+	spin_lock_irqsave(&dev->lock, flags);
+	if (req->status)
+		dev->ep0_status = req->status;
+	else
+		dev->ep0_status = req->actual;
+	if (dev->ep0_in_pending)
+		dev->ep0_in_pending = false;
+	else
+		dev->ep0_out_pending = false;
+	spin_unlock_irqrestore(&dev->lock, flags);
+
+	complete(&dev->ep0_done);
+}
+
+static int gadget_bind(struct usb_gadget *gadget,
+			struct usb_gadget_driver *driver)
+{
+	int ret = 0;
+	struct raw_dev *dev = container_of(driver, struct raw_dev, driver);
+	struct usb_request *req;
+	unsigned long flags;
+
+	if (strcmp(gadget->name, dev->udc_name) != 0)
+		return -ENODEV;
+
+	set_gadget_data(gadget, dev);
+	req = usb_ep_alloc_request(gadget->ep0, GFP_KERNEL);
+	if (!req) {
+		dev_err(&gadget->dev, "usb_ep_alloc_request failed\n");
+		set_gadget_data(gadget, NULL);
+		return -ENOMEM;
+	}
+
+	spin_lock_irqsave(&dev->lock, flags);
+	dev->req = req;
+	dev->req->context = dev;
+	dev->req->complete = gadget_ep0_complete;
+	dev->gadget = gadget;
+	spin_unlock_irqrestore(&dev->lock, flags);
+
+	/* Matches kref_put() in gadget_unbind(). */
+	kref_get(&dev->count);
+
+	ret = raw_queue_event(dev, USB_RAW_EVENT_CONNECT, 0, NULL);
+	if (ret < 0)
+		dev_err(&gadget->dev, "failed to queue event\n");
+
+	return ret;
+}
+
+static void gadget_unbind(struct usb_gadget *gadget)
+{
+	struct raw_dev *dev = get_gadget_data(gadget);
+
+	set_gadget_data(gadget, NULL);
+	/* Matches kref_get() in gadget_bind(). */
+	kref_put(&dev->count, dev_free);
+}
+
+static int gadget_setup(struct usb_gadget *gadget,
+			const struct usb_ctrlrequest *ctrl)
+{
+	int ret = 0;
+	struct raw_dev *dev = get_gadget_data(gadget);
+	unsigned long flags;
+
+	spin_lock_irqsave(&dev->lock, flags);
+	if (dev->state != STATE_DEV_RUNNING) {
+		dev_err(&gadget->dev, "ignoring, device is not running\n");
+		ret = -ENODEV;
+		goto out_unlock;
+	}
+	if (dev->ep0_in_pending || dev->ep0_out_pending) {
+		dev_dbg(&gadget->dev, "stalling, request already pending\n");
+		ret = -EBUSY;
+		goto out_unlock;
+	}
+	if ((ctrl->bRequestType & USB_DIR_IN) && ctrl->wLength)
+		dev->ep0_in_pending = true;
+	else
+		dev->ep0_out_pending = true;
+	spin_unlock_irqrestore(&dev->lock, flags);
+
+	ret = raw_queue_event(dev, USB_RAW_EVENT_CONTROL, sizeof(*ctrl), ctrl);
+	if (ret < 0)
+		dev_err(&gadget->dev, "failed to queue event\n");
+	goto out;
+
+out_unlock:
+	spin_unlock_irqrestore(&dev->lock, flags);
+out:
+	return ret;
+}
+
+/* These are currently unused but present in case UDC driver requires them. */
+static void gadget_disconnect(struct usb_gadget *gadget) { }
+static void gadget_suspend(struct usb_gadget *gadget) { }
+static void gadget_resume(struct usb_gadget *gadget) { }
+static void gadget_reset(struct usb_gadget *gadget) { }
+
+/*----------------------------------------------------------------------*/
+
+static struct miscdevice raw_misc_device;
+
+static int raw_open(struct inode *inode, struct file *fd)
+{
+	struct raw_dev *dev;
+
+	/* Nonblocking I/O is not supported yet. */
+	if (fd->f_flags & O_NONBLOCK)
+		return -EINVAL;
+
+	dev = dev_new();
+	if (!dev)
+		return -ENOMEM;
+	fd->private_data = dev;
+	dev->state = STATE_DEV_OPENED;
+	dev->dev = raw_misc_device.this_device;
+	return 0;
+}
+
+static int raw_release(struct inode *inode, struct file *fd)
+{
+	int ret = 0;
+	struct raw_dev *dev = fd->private_data;
+	unsigned long flags;
+	bool unregister = false;
+
+	spin_lock_irqsave(&dev->lock, flags);
+	dev->state = STATE_DEV_CLOSED;
+	if (!dev->gadget) {
+		spin_unlock_irqrestore(&dev->lock, flags);
+		goto out_put;
+	}
+	if (dev->gadget_registered)
+		unregister = true;
+	dev->gadget_registered = false;
+	spin_unlock_irqrestore(&dev->lock, flags);
+
+	if (unregister) {
+		ret = usb_gadget_unregister_driver(&dev->driver);
+		if (ret != 0)
+			dev_err(dev->dev,
+				"usb_gadget_unregister_driver() failed with %d\n",
+				ret);
+		/* Matches kref_get() in raw_ioctl_run(). */
+		kref_put(&dev->count, dev_free);
+	}
+
+out_put:
+	/* Matches dev_new() in raw_open(). */
+	kref_put(&dev->count, dev_free);
+	return ret;
+}
+
+/*----------------------------------------------------------------------*/
+
+static int raw_ioctl_init(struct raw_dev *dev, unsigned long value)
+{
+	int ret = 0;
+	struct usb_raw_init arg;
+	char *udc_driver_name;
+	char *udc_device_name;
+	unsigned long flags;
+
+	ret = copy_from_user(&arg, (void __user *)value, sizeof(arg));
+	if (ret)
+		return ret;
+
+	switch (arg.speed) {
+	case USB_SPEED_UNKNOWN:
+		arg.speed = USB_SPEED_HIGH;
+		break;
+	case USB_SPEED_LOW:
+	case USB_SPEED_FULL:
+	case USB_SPEED_HIGH:
+	case USB_SPEED_SUPER:
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	udc_driver_name = kmalloc(UDC_NAME_LENGTH_MAX, GFP_KERNEL);
+	if (!udc_driver_name)
+		return -ENOMEM;
+	ret = strscpy(udc_driver_name, &arg.driver_name[0],
+				UDC_NAME_LENGTH_MAX);
+	if (ret < 0) {
+		kfree(udc_driver_name);
+		return ret;
+	}
+	ret = 0;
+
+	udc_device_name = kmalloc(UDC_NAME_LENGTH_MAX, GFP_KERNEL);
+	if (!udc_device_name) {
+		kfree(udc_driver_name);
+		return -ENOMEM;
+	}
+	ret = strscpy(udc_device_name, &arg.device_name[0],
+				UDC_NAME_LENGTH_MAX);
+	if (ret < 0) {
+		kfree(udc_driver_name);
+		kfree(udc_device_name);
+		return ret;
+	}
+	ret = 0;
+
+	spin_lock_irqsave(&dev->lock, flags);
+	if (dev->state != STATE_DEV_OPENED) {
+		dev_dbg(dev->dev, "fail, device is not opened\n");
+		kfree(udc_driver_name);
+		kfree(udc_device_name);
+		ret = -EINVAL;
+		goto out_unlock;
+	}
+	dev->udc_name = udc_driver_name;
+
+	dev->driver.function = DRIVER_DESC;
+	dev->driver.max_speed = arg.speed;
+	dev->driver.setup = gadget_setup;
+	dev->driver.disconnect = gadget_disconnect;
+	dev->driver.bind = gadget_bind;
+	dev->driver.unbind = gadget_unbind;
+	dev->driver.suspend = gadget_suspend;
+	dev->driver.resume = gadget_resume;
+	dev->driver.reset = gadget_reset;
+	dev->driver.driver.name = DRIVER_NAME;
+	dev->driver.udc_name = udc_device_name;
+	dev->driver.match_existing_only = 1;
+
+	dev->state = STATE_DEV_INITIALIZED;
+
+out_unlock:
+	spin_unlock_irqrestore(&dev->lock, flags);
+	return ret;
+}
+
+static int raw_ioctl_run(struct raw_dev *dev, unsigned long value)
+{
+	int ret = 0;
+	unsigned long flags;
+
+	if (value)
+		return -EINVAL;
+
+	spin_lock_irqsave(&dev->lock, flags);
+	if (dev->state != STATE_DEV_INITIALIZED) {
+		dev_dbg(dev->dev, "fail, device is not initialized\n");
+		ret = -EINVAL;
+		goto out_unlock;
+	}
+	spin_unlock_irqrestore(&dev->lock, flags);
+
+	ret = usb_gadget_probe_driver(&dev->driver);
+
+	spin_lock_irqsave(&dev->lock, flags);
+	if (ret) {
+		dev_err(dev->dev,
+			"fail, usb_gadget_probe_driver returned %d\n", ret);
+		dev->state = STATE_DEV_FAILED;
+		goto out_unlock;
+	}
+	dev->gadget_registered = true;
+	dev->state = STATE_DEV_RUNNING;
+	/* Matches kref_put() in raw_release(). */
+	kref_get(&dev->count);
+
+out_unlock:
+	spin_unlock_irqrestore(&dev->lock, flags);
+	return ret;
+}
+
+static int raw_ioctl_event_fetch(struct raw_dev *dev, unsigned long value)
+{
+	int ret = 0;
+	struct usb_raw_event arg;
+	unsigned long flags;
+	struct usb_raw_event *event;
+	uint32_t length;
+
+	ret = copy_from_user(&arg, (void __user *)value, sizeof(arg));
+	if (ret)
+		return ret;
+
+	spin_lock_irqsave(&dev->lock, flags);
+	if (dev->state != STATE_DEV_RUNNING) {
+		dev_dbg(dev->dev, "fail, device is not running\n");
+		spin_unlock_irqrestore(&dev->lock, flags);
+		return -EINVAL;
+	}
+	if (!dev->gadget) {
+		dev_dbg(dev->dev, "fail, gadget is not bound\n");
+		spin_unlock_irqrestore(&dev->lock, flags);
+		return -EBUSY;
+	}
+	spin_unlock_irqrestore(&dev->lock, flags);
+
+	event = raw_event_queue_fetch(&dev->queue);
+	if (!event) {
+		dev_dbg(&dev->gadget->dev, "event fetching interrupted\n");
+		return -EINTR;
+	}
+	length = min(arg.length, event->length);
+	ret = copy_to_user((void __user *)value, event,
+				sizeof(*event) + length);
+	return ret;
+}
+
+static void *raw_alloc_io_data(struct usb_raw_ep_io *io, void __user *ptr,
+				bool get_from_user)
+{
+	int ret;
+	void *data;
+
+	ret = copy_from_user(io, ptr, sizeof(*io));
+	if (ret)
+		return ERR_PTR(ret);
+	if (io->ep >= USB_RAW_MAX_ENDPOINTS)
+		return ERR_PTR(-EINVAL);
+	if (!usb_raw_io_flags_valid(io->flags))
+		return ERR_PTR(-EINVAL);
+	if (io->length > PAGE_SIZE)
+		return ERR_PTR(-EINVAL);
+	if (get_from_user)
+		data = memdup_user(ptr + sizeof(*io), io->length);
+	else {
+		data = kmalloc(io->length, GFP_KERNEL);
+		if (!data)
+			data = ERR_PTR(-ENOMEM);
+	}
+	return data;
+}
+
+static int raw_process_ep0_io(struct raw_dev *dev, struct usb_raw_ep_io *io,
+				void *data, bool in)
+{
+	int ret = 0;
+	unsigned long flags;
+
+	spin_lock_irqsave(&dev->lock, flags);
+	if (dev->state != STATE_DEV_RUNNING) {
+		dev_dbg(dev->dev, "fail, device is not running\n");
+		ret = -EINVAL;
+		goto out_unlock;
+	}
+	if (!dev->gadget) {
+		dev_dbg(dev->dev, "fail, gadget is not bound\n");
+		ret = -EBUSY;
+		goto out_unlock;
+	}
+	if (dev->ep0_urb_queued) {
+		dev_dbg(&dev->gadget->dev, "fail, urb already queued\n");
+		ret = -EBUSY;
+		goto out_unlock;
+	}
+	if ((in && !dev->ep0_in_pending) ||
+			(!in && !dev->ep0_out_pending)) {
+		dev_dbg(&dev->gadget->dev, "fail, wrong direction\n");
+		ret = -EBUSY;
+		goto out_unlock;
+	}
+	if (WARN_ON(in && dev->ep0_out_pending)) {
+		ret = -ENODEV;
+		dev->state = STATE_DEV_FAILED;
+		goto out_done;
+	}
+	if (WARN_ON(!in && dev->ep0_in_pending)) {
+		ret = -ENODEV;
+		dev->state = STATE_DEV_FAILED;
+		goto out_done;
+	}
+
+	dev->req->buf = data;
+	dev->req->length = io->length;
+	dev->req->zero = usb_raw_io_flags_zero(io->flags);
+	dev->ep0_urb_queued = true;
+	spin_unlock_irqrestore(&dev->lock, flags);
+
+	ret = usb_ep_queue(dev->gadget->ep0, dev->req, GFP_KERNEL);
+	if (ret) {
+		dev_err(&dev->gadget->dev,
+				"fail, usb_ep_queue returned %d\n", ret);
+		spin_lock_irqsave(&dev->lock, flags);
+		dev->state = STATE_DEV_FAILED;
+		goto out_done;
+	}
+
+	ret = wait_for_completion_interruptible(&dev->ep0_done);
+	if (ret) {
+		dev_dbg(&dev->gadget->dev, "wait interrupted\n");
+		usb_ep_dequeue(dev->gadget->ep0, dev->req);
+		wait_for_completion(&dev->ep0_done);
+		spin_lock_irqsave(&dev->lock, flags);
+		goto out_done;
+	}
+
+	spin_lock_irqsave(&dev->lock, flags);
+	ret = dev->ep0_status;
+
+out_done:
+	dev->ep0_urb_queued = false;
+out_unlock:
+	spin_unlock_irqrestore(&dev->lock, flags);
+	return ret;
+}
+
+static int raw_ioctl_ep0_write(struct raw_dev *dev, unsigned long value)
+{
+	int ret = 0;
+	void *data;
+	struct usb_raw_ep_io io;
+
+	data = raw_alloc_io_data(&io, (void __user *)value, true);
+	if (IS_ERR(data))
+		return PTR_ERR(data);
+	ret = raw_process_ep0_io(dev, &io, data, true);
+	kfree(data);
+	return ret;
+}
+
+static int raw_ioctl_ep0_read(struct raw_dev *dev, unsigned long value)
+{
+	int ret = 0;
+	void *data;
+	struct usb_raw_ep_io io;
+	unsigned int length;
+
+	data = raw_alloc_io_data(&io, (void __user *)value, false);
+	if (IS_ERR(data))
+		return PTR_ERR(data);
+	ret = raw_process_ep0_io(dev, &io, data, false);
+	if (ret < 0) {
+		kfree(data);
+		return ret;
+	}
+	length = min(io.length, (unsigned int)ret);
+	ret = copy_to_user((void __user *)(value + sizeof(io)), data, length);
+	kfree(data);
+	return ret;
+}
+
+static bool check_ep_caps(struct usb_ep *ep,
+				struct usb_endpoint_descriptor *desc)
+{
+	switch (usb_endpoint_type(desc)) {
+	case USB_ENDPOINT_XFER_ISOC:
+		if (!ep->caps.type_iso)
+			return false;
+		break;
+	case USB_ENDPOINT_XFER_BULK:
+		if (!ep->caps.type_bulk)
+			return false;
+		break;
+	case USB_ENDPOINT_XFER_INT:
+		if (!ep->caps.type_int)
+			return false;
+		break;
+	default:
+		return false;
+	}
+
+	if (usb_endpoint_dir_in(desc) && !ep->caps.dir_in)
+		return false;
+	if (usb_endpoint_dir_out(desc) && !ep->caps.dir_out)
+		return false;
+
+	return true;
+}
+
+static int raw_ioctl_ep_enable(struct raw_dev *dev, unsigned long value)
+{
+	int ret = 0, i;
+	unsigned long flags;
+	struct usb_endpoint_descriptor *desc;
+	struct usb_ep *ep = NULL;
+
+	desc = memdup_user((void __user *)value, sizeof(*desc));
+	if (IS_ERR(desc))
+		return PTR_ERR(desc);
+
+	/*
+	 * Endpoints with a maxpacket length of 0 can cause crashes in UDC
+	 * drivers.
+	 */
+	if (usb_endpoint_maxp(desc) == 0) {
+		dev_dbg(dev->dev, "fail, bad endpoint maxpacket\n");
+		kfree(desc);
+		return -EINVAL;
+	}
+
+	spin_lock_irqsave(&dev->lock, flags);
+	if (dev->state != STATE_DEV_RUNNING) {
+		dev_dbg(dev->dev, "fail, device is not running\n");
+		ret = -EINVAL;
+		goto out_free;
+	}
+	if (!dev->gadget) {
+		dev_dbg(dev->dev, "fail, gadget is not bound\n");
+		ret = -EBUSY;
+		goto out_free;
+	}
+
+	for (i = 0; i < USB_RAW_MAX_ENDPOINTS; i++) {
+		if (dev->eps[i].state == STATE_EP_ENABLED)
+			continue;
+		break;
+	}
+	if (i == USB_RAW_MAX_ENDPOINTS) {
+		dev_dbg(&dev->gadget->dev,
+				"fail, no device endpoints available\n");
+		ret = -EBUSY;
+		goto out_free;
+	}
+
+	gadget_for_each_ep(ep, dev->gadget) {
+		if (ep->enabled)
+			continue;
+		if (!check_ep_caps(ep, desc))
+			continue;
+		ep->desc = desc;
+		ret = usb_ep_enable(ep);
+		if (ret < 0) {
+			dev_err(&dev->gadget->dev,
+				"fail, usb_ep_enable returned %d\n", ret);
+			goto out_free;
+		}
+		dev->eps[i].req = usb_ep_alloc_request(ep, GFP_ATOMIC);
+		if (!dev->eps[i].req) {
+			dev_err(&dev->gadget->dev,
+				"fail, usb_ep_alloc_request failed\n");
+			usb_ep_disable(ep);
+			ret = -ENOMEM;
+			goto out_free;
+		}
+		dev->eps[i].ep = ep;
+		dev->eps[i].state = STATE_EP_ENABLED;
+		ep->driver_data = &dev->eps[i];
+		ret = i;
+		goto out_unlock;
+	}
+
+	dev_dbg(&dev->gadget->dev, "fail, no gadget endpoints available\n");
+	ret = -EBUSY;
+
+out_free:
+	kfree(desc);
+out_unlock:
+	spin_unlock_irqrestore(&dev->lock, flags);
+	return ret;
+}
+
+static int raw_ioctl_ep_disable(struct raw_dev *dev, unsigned long value)
+{
+	int ret = 0, i = value;
+	unsigned long flags;
+	const void *desc;
+
+	if (i < 0 || i >= USB_RAW_MAX_ENDPOINTS)
+		return -EINVAL;
+
+	spin_lock_irqsave(&dev->lock, flags);
+	if (dev->state != STATE_DEV_RUNNING) {
+		dev_dbg(dev->dev, "fail, device is not running\n");
+		ret = -EINVAL;
+		goto out_unlock;
+	}
+	if (!dev->gadget) {
+		dev_dbg(dev->dev, "fail, gadget is not bound\n");
+		ret = -EBUSY;
+		goto out_unlock;
+	}
+	if (dev->eps[i].state != STATE_EP_ENABLED) {
+		dev_dbg(&dev->gadget->dev, "fail, endpoint is not enabled\n");
+		ret = -EINVAL;
+		goto out_unlock;
+	}
+	if (dev->eps[i].disabling) {
+		dev_dbg(&dev->gadget->dev,
+				"fail, disable already in progress\n");
+		ret = -EINVAL;
+		goto out_unlock;
+	}
+	if (dev->eps[i].urb_queued) {
+		dev_dbg(&dev->gadget->dev,
+				"fail, waiting for urb completion\n");
+		ret = -EINVAL;
+		goto out_unlock;
+	}
+	dev->eps[i].disabling = true;
+	spin_unlock_irqrestore(&dev->lock, flags);
+
+	usb_ep_disable(dev->eps[i].ep);
+
+	spin_lock_irqsave(&dev->lock, flags);
+	usb_ep_free_request(dev->eps[i].ep, dev->eps[i].req);
+	desc = dev->eps[i].ep->desc;
+	dev->eps[i].ep = NULL;
+	dev->eps[i].state = STATE_EP_DISABLED;
+	kfree(desc);
+	dev->eps[i].disabling = false;
+
+out_unlock:
+	spin_unlock_irqrestore(&dev->lock, flags);
+	return ret;
+}
+
+static void gadget_ep_complete(struct usb_ep *ep, struct usb_request *req)
+{
+	struct raw_ep *r_ep = (struct raw_ep *)ep->driver_data;
+	struct raw_dev *dev = r_ep->dev;
+	unsigned long flags;
+
+	spin_lock_irqsave(&dev->lock, flags);
+	if (req->status)
+		r_ep->status = req->status;
+	else
+		r_ep->status = req->actual;
+	spin_unlock_irqrestore(&dev->lock, flags);
+
+	complete((struct completion *)req->context);
+}
+
+static int raw_process_ep_io(struct raw_dev *dev, struct usb_raw_ep_io *io,
+				void *data, bool in)
+{
+	int ret = 0;
+	unsigned long flags;
+	struct raw_ep *ep = &dev->eps[io->ep];
+	DECLARE_COMPLETION_ONSTACK(done);
+
+	spin_lock_irqsave(&dev->lock, flags);
+	if (dev->state != STATE_DEV_RUNNING) {
+		dev_dbg(dev->dev, "fail, device is not running\n");
+		ret = -EINVAL;
+		goto out_unlock;
+	}
+	if (!dev->gadget) {
+		dev_dbg(dev->dev, "fail, gadget is not bound\n");
+		ret = -EBUSY;
+		goto out_unlock;
+	}
+	if (ep->state != STATE_EP_ENABLED) {
+		dev_dbg(&dev->gadget->dev, "fail, endpoint is not enabled\n");
+		ret = -EBUSY;
+		goto out_unlock;
+	}
+	if (ep->disabling) {
+		dev_dbg(&dev->gadget->dev,
+				"fail, endpoint is already being disabled\n");
+		ret = -EBUSY;
+		goto out_unlock;
+	}
+	if (ep->urb_queued) {
+		dev_dbg(&dev->gadget->dev, "fail, urb already queued\n");
+		ret = -EBUSY;
+		goto out_unlock;
+	}
+	if ((in && !ep->ep->caps.dir_in) || (!in && ep->ep->caps.dir_in)) {
+		dev_dbg(&dev->gadget->dev, "fail, wrong direction\n");
+		ret = -EINVAL;
+		goto out_unlock;
+	}
+
+	ep->dev = dev;
+	ep->req->context = &done;
+	ep->req->complete = gadget_ep_complete;
+	ep->req->buf = data;
+	ep->req->length = io->length;
+	ep->req->zero = usb_raw_io_flags_zero(io->flags);
+	ep->urb_queued = true;
+	spin_unlock_irqrestore(&dev->lock, flags);
+
+	ret = usb_ep_queue(ep->ep, ep->req, GFP_KERNEL);
+	if (ret) {
+		dev_err(&dev->gadget->dev,
+				"fail, usb_ep_queue returned %d\n", ret);
+		spin_lock_irqsave(&dev->lock, flags);
+		dev->state = STATE_DEV_FAILED;
+		goto out_done;
+	}
+
+	ret = wait_for_completion_interruptible(&done);
+	if (ret) {
+		dev_dbg(&dev->gadget->dev, "wait interrupted\n");
+		usb_ep_dequeue(ep->ep, ep->req);
+		wait_for_completion(&done);
+		spin_lock_irqsave(&dev->lock, flags);
+		goto out_done;
+	}
+
+	spin_lock_irqsave(&dev->lock, flags);
+	ret = ep->status;
+
+out_done:
+	ep->urb_queued = false;
+out_unlock:
+	spin_unlock_irqrestore(&dev->lock, flags);
+	return ret;
+}
+
+static int raw_ioctl_ep_write(struct raw_dev *dev, unsigned long value)
+{
+	int ret = 0;
+	char *data;
+	struct usb_raw_ep_io io;
+
+	data = raw_alloc_io_data(&io, (void __user *)value, true);
+	if (IS_ERR(data))
+		return PTR_ERR(data);
+	ret = raw_process_ep_io(dev, &io, data, true);
+	kfree(data);
+	return ret;
+}
+
+static int raw_ioctl_ep_read(struct raw_dev *dev, unsigned long value)
+{
+	int ret = 0;
+	char *data;
+	struct usb_raw_ep_io io;
+	unsigned int length;
+
+	data = raw_alloc_io_data(&io, (void __user *)value, false);
+	if (IS_ERR(data))
+		return PTR_ERR(data);
+	ret = raw_process_ep_io(dev, &io, data, false);
+	if (ret < 0) {
+		kfree(data);
+		return ret;
+	}
+	length = min(io.length, (unsigned int)ret);
+	ret = copy_to_user((void __user *)(value + sizeof(io)), data, length);
+	kfree(data);
+	return ret;
+}
+
+static int raw_ioctl_configure(struct raw_dev *dev, unsigned long value)
+{
+	int ret = 0;
+	unsigned long flags;
+
+	if (value)
+		return -EINVAL;
+	spin_lock_irqsave(&dev->lock, flags);
+	if (dev->state != STATE_DEV_RUNNING) {
+		dev_dbg(dev->dev, "fail, device is not running\n");
+		ret = -EINVAL;
+		goto out_unlock;
+	}
+	if (!dev->gadget) {
+		dev_dbg(dev->dev, "fail, gadget is not bound\n");
+		ret = -EBUSY;
+		goto out_unlock;
+	}
+	usb_gadget_set_state(dev->gadget, USB_STATE_CONFIGURED);
+
+out_unlock:
+	spin_unlock_irqrestore(&dev->lock, flags);
+	return ret;
+}
+
+static int raw_ioctl_vbus_draw(struct raw_dev *dev, unsigned long value)
+{
+	int ret = 0;
+	unsigned long flags;
+
+	spin_lock_irqsave(&dev->lock, flags);
+	if (dev->state != STATE_DEV_RUNNING) {
+		dev_dbg(dev->dev, "fail, device is not running\n");
+		ret = -EINVAL;
+		goto out_unlock;
+	}
+	if (!dev->gadget) {
+		dev_dbg(dev->dev, "fail, gadget is not bound\n");
+		ret = -EBUSY;
+		goto out_unlock;
+	}
+	usb_gadget_vbus_draw(dev->gadget, 2 * value);
+
+out_unlock:
+	spin_unlock_irqrestore(&dev->lock, flags);
+	return ret;
+}
+
+static long raw_ioctl(struct file *fd, unsigned int cmd, unsigned long value)
+{
+	struct raw_dev *dev = fd->private_data;
+	int ret = 0;
+
+	if (!dev)
+		return -EBUSY;
+
+	switch (cmd) {
+	case USB_RAW_IOCTL_INIT:
+		ret = raw_ioctl_init(dev, value);
+		break;
+	case USB_RAW_IOCTL_RUN:
+		ret = raw_ioctl_run(dev, value);
+		break;
+	case USB_RAW_IOCTL_EVENT_FETCH:
+		ret = raw_ioctl_event_fetch(dev, value);
+		break;
+	case USB_RAW_IOCTL_EP0_WRITE:
+		ret = raw_ioctl_ep0_write(dev, value);
+		break;
+	case USB_RAW_IOCTL_EP0_READ:
+		ret = raw_ioctl_ep0_read(dev, value);
+		break;
+	case USB_RAW_IOCTL_EP_ENABLE:
+		ret = raw_ioctl_ep_enable(dev, value);
+		break;
+	case USB_RAW_IOCTL_EP_DISABLE:
+		ret = raw_ioctl_ep_disable(dev, value);
+		break;
+	case USB_RAW_IOCTL_EP_WRITE:
+		ret = raw_ioctl_ep_write(dev, value);
+		break;
+	case USB_RAW_IOCTL_EP_READ:
+		ret = raw_ioctl_ep_read(dev, value);
+		break;
+	case USB_RAW_IOCTL_CONFIGURE:
+		ret = raw_ioctl_configure(dev, value);
+		break;
+	case USB_RAW_IOCTL_VBUS_DRAW:
+		ret = raw_ioctl_vbus_draw(dev, value);
+		break;
+	default:
+		ret = -EINVAL;
+	}
+
+	return ret;
+}
+
+/*----------------------------------------------------------------------*/
+
+static const struct file_operations raw_fops = {
+	.open =			raw_open,
+	.unlocked_ioctl =	raw_ioctl,
+	.compat_ioctl =		raw_ioctl,
+	.release =		raw_release,
+	.llseek =		no_llseek,
+};
+
+static struct miscdevice raw_misc_device = {
+	.minor = MISC_DYNAMIC_MINOR,
+	.name = DRIVER_NAME,
+	.fops = &raw_fops,
+};
+
+module_misc_device(raw_misc_device);
diff --git a/drivers/usb/gadget/udc/Kconfig b/drivers/usb/gadget/udc/Kconfig
index 797d6ace8994..1ff82285ac7a 100644
--- a/drivers/usb/gadget/udc/Kconfig
+++ b/drivers/usb/gadget/udc/Kconfig
@@ -441,6 +441,16 @@ config USB_GADGET_XILINX
 	  dynamically linked module called "udc-xilinx" and force all
 	  gadget drivers to also be dynamically linked.
 
+config USB_MAX3420_UDC
+	tristate "MAX3420 (USB-over-SPI) support"
+	depends on SPI
+	help
+	  The Maxim MAX3420 chip supports USB2.0 full-speed peripheral mode.
+	  The MAX3420 is run by SPI interface, and hence the dependency.
+
+	  To compile this driver as a module, choose M here: the module will
+	  be called max3420_udc
+
 config USB_TEGRA_XUDC
 	tristate "NVIDIA Tegra Superspeed USB 3.0 Device Controller"
 	depends on ARCH_TEGRA || COMPILE_TEST
diff --git a/drivers/usb/gadget/udc/Makefile b/drivers/usb/gadget/udc/Makefile
index f6777e654a8e..f5a7ce28aecd 100644
--- a/drivers/usb/gadget/udc/Makefile
+++ b/drivers/usb/gadget/udc/Makefile
@@ -42,3 +42,4 @@ obj-$(CONFIG_USB_GADGET_XILINX)	+= udc-xilinx.o
 obj-$(CONFIG_USB_SNP_UDC_PLAT) += snps_udc_plat.o
 obj-$(CONFIG_USB_ASPEED_VHUB)	+= aspeed-vhub/
 obj-$(CONFIG_USB_BDC_UDC)	+= bdc/
+obj-$(CONFIG_USB_MAX3420_UDC)	+= max3420_udc.o
diff --git a/drivers/usb/gadget/udc/aspeed-vhub/Kconfig b/drivers/usb/gadget/udc/aspeed-vhub/Kconfig
index 83ba8a2eb6af..605500b19cf3 100644
--- a/drivers/usb/gadget/udc/aspeed-vhub/Kconfig
+++ b/drivers/usb/gadget/udc/aspeed-vhub/Kconfig
@@ -4,5 +4,5 @@ config USB_ASPEED_VHUB
 	depends on ARCH_ASPEED || COMPILE_TEST
 	depends on USB_LIBCOMPOSITE
 	help
-	  USB peripheral controller for the Aspeed AST2500 family
-	  SoCs supporting the "vHub" functionality and USB2.0
+	  USB peripheral controller for the Aspeed AST2400, AST2500 and
+	  AST2600 family SoCs supporting the "vHub" functionality and USB2.0
diff --git a/drivers/usb/gadget/udc/aspeed-vhub/core.c b/drivers/usb/gadget/udc/aspeed-vhub/core.c
index 90b134d5dca9..f8d35dd60c34 100644
--- a/drivers/usb/gadget/udc/aspeed-vhub/core.c
+++ b/drivers/usb/gadget/udc/aspeed-vhub/core.c
@@ -99,7 +99,7 @@ static irqreturn_t ast_vhub_irq(int irq, void *data)
 {
 	struct ast_vhub *vhub = data;
 	irqreturn_t iret = IRQ_NONE;
-	u32 istat;
+	u32 i, istat;
 
 	/* Stale interrupt while tearing down */
 	if (!vhub->ep0_bufs)
@@ -121,10 +121,10 @@ static irqreturn_t ast_vhub_irq(int irq, void *data)
 
 	/* Handle generic EPs first */
 	if (istat & VHUB_IRQ_EP_POOL_ACK_STALL) {
-		u32 i, ep_acks = readl(vhub->regs + AST_VHUB_EP_ACK_ISR);
+		u32 ep_acks = readl(vhub->regs + AST_VHUB_EP_ACK_ISR);
 		writel(ep_acks, vhub->regs + AST_VHUB_EP_ACK_ISR);
 
-		for (i = 0; ep_acks && i < AST_VHUB_NUM_GEN_EPs; i++) {
+		for (i = 0; ep_acks && i < vhub->max_epns; i++) {
 			u32 mask = VHUB_EP_IRQ(i);
 			if (ep_acks & mask) {
 				ast_vhub_epn_ack_irq(&vhub->epns[i]);
@@ -134,21 +134,11 @@ static irqreturn_t ast_vhub_irq(int irq, void *data)
 	}
 
 	/* Handle device interrupts */
-	if (istat & (VHUB_IRQ_DEVICE1 |
-		     VHUB_IRQ_DEVICE2 |
-		     VHUB_IRQ_DEVICE3 |
-		     VHUB_IRQ_DEVICE4 |
-		     VHUB_IRQ_DEVICE5)) {
-		if (istat & VHUB_IRQ_DEVICE1)
-			ast_vhub_dev_irq(&vhub->ports[0].dev);
-		if (istat & VHUB_IRQ_DEVICE2)
-			ast_vhub_dev_irq(&vhub->ports[1].dev);
-		if (istat & VHUB_IRQ_DEVICE3)
-			ast_vhub_dev_irq(&vhub->ports[2].dev);
-		if (istat & VHUB_IRQ_DEVICE4)
-			ast_vhub_dev_irq(&vhub->ports[3].dev);
-		if (istat & VHUB_IRQ_DEVICE5)
-			ast_vhub_dev_irq(&vhub->ports[4].dev);
+	for (i = 0; i < vhub->max_ports; i++) {
+		u32 dev_mask = VHUB_IRQ_DEVICE1 << i;
+
+		if (istat & dev_mask)
+			ast_vhub_dev_irq(&vhub->ports[i].dev);
 	}
 
 	/* Handle top-level vHub EP0 interrupts */
@@ -182,7 +172,7 @@ static irqreturn_t ast_vhub_irq(int irq, void *data)
 
 void ast_vhub_init_hw(struct ast_vhub *vhub)
 {
-	u32 ctrl;
+	u32 ctrl, port_mask, epn_mask;
 
 	UDCDBG(vhub,"(Re)Starting HW ...\n");
 
@@ -222,15 +212,20 @@ void ast_vhub_init_hw(struct ast_vhub *vhub)
 	}
 
 	/* Reset all devices */
-	writel(VHUB_SW_RESET_ALL, vhub->regs + AST_VHUB_SW_RESET);
+	port_mask = GENMASK(vhub->max_ports, 1);
+	writel(VHUB_SW_RESET_ROOT_HUB |
+	       VHUB_SW_RESET_DMA_CONTROLLER |
+	       VHUB_SW_RESET_EP_POOL |
+	       port_mask, vhub->regs + AST_VHUB_SW_RESET);
 	udelay(1);
 	writel(0, vhub->regs + AST_VHUB_SW_RESET);
 
 	/* Disable and cleanup EP ACK/NACK interrupts */
+	epn_mask = GENMASK(vhub->max_epns - 1, 0);
 	writel(0, vhub->regs + AST_VHUB_EP_ACK_IER);
 	writel(0, vhub->regs + AST_VHUB_EP_NACK_IER);
-	writel(VHUB_EP_IRQ_ALL, vhub->regs + AST_VHUB_EP_ACK_ISR);
-	writel(VHUB_EP_IRQ_ALL, vhub->regs + AST_VHUB_EP_NACK_ISR);
+	writel(epn_mask, vhub->regs + AST_VHUB_EP_ACK_ISR);
+	writel(epn_mask, vhub->regs + AST_VHUB_EP_NACK_ISR);
 
 	/* Default settings for EP0, enable HW hub EP1 */
 	writel(0, vhub->regs + AST_VHUB_EP0_CTRL);
@@ -273,7 +268,7 @@ static int ast_vhub_remove(struct platform_device *pdev)
 		return 0;
 
 	/* Remove devices */
-	for (i = 0; i < AST_VHUB_NUM_PORTS; i++)
+	for (i = 0; i < vhub->max_ports; i++)
 		ast_vhub_del_dev(&vhub->ports[i].dev);
 
 	spin_lock_irqsave(&vhub->lock, flags);
@@ -295,7 +290,7 @@ static int ast_vhub_remove(struct platform_device *pdev)
 	if (vhub->ep0_bufs)
 		dma_free_coherent(&pdev->dev,
 				  AST_VHUB_EP0_MAX_PACKET *
-				  (AST_VHUB_NUM_PORTS + 1),
+				  (vhub->max_ports + 1),
 				  vhub->ep0_bufs,
 				  vhub->ep0_bufs_dma);
 	vhub->ep0_bufs = NULL;
@@ -309,11 +304,32 @@ static int ast_vhub_probe(struct platform_device *pdev)
 	struct ast_vhub *vhub;
 	struct resource *res;
 	int i, rc = 0;
+	const struct device_node *np = pdev->dev.of_node;
 
 	vhub = devm_kzalloc(&pdev->dev, sizeof(*vhub), GFP_KERNEL);
 	if (!vhub)
 		return -ENOMEM;
 
+	rc = of_property_read_u32(np, "aspeed,vhub-downstream-ports",
+				  &vhub->max_ports);
+	if (rc < 0)
+		vhub->max_ports = AST_VHUB_NUM_PORTS;
+
+	vhub->ports = devm_kcalloc(&pdev->dev, vhub->max_ports,
+				   sizeof(*vhub->ports), GFP_KERNEL);
+	if (!vhub->ports)
+		return -ENOMEM;
+
+	rc = of_property_read_u32(np, "aspeed,vhub-generic-endpoints",
+				  &vhub->max_epns);
+	if (rc < 0)
+		vhub->max_epns = AST_VHUB_NUM_GEN_EPs;
+
+	vhub->epns = devm_kcalloc(&pdev->dev, vhub->max_epns,
+				  sizeof(*vhub->epns), GFP_KERNEL);
+	if (!vhub->epns)
+		return -ENOMEM;
+
 	spin_lock_init(&vhub->lock);
 	vhub->pdev = pdev;
 
@@ -366,7 +382,7 @@ static int ast_vhub_probe(struct platform_device *pdev)
 	 */
 	vhub->ep0_bufs = dma_alloc_coherent(&pdev->dev,
 					    AST_VHUB_EP0_MAX_PACKET *
-					    (AST_VHUB_NUM_PORTS + 1),
+					    (vhub->max_ports + 1),
 					    &vhub->ep0_bufs_dma, GFP_KERNEL);
 	if (!vhub->ep0_bufs) {
 		dev_err(&pdev->dev, "Failed to allocate EP0 DMA buffers\n");
@@ -380,7 +396,7 @@ static int ast_vhub_probe(struct platform_device *pdev)
 	ast_vhub_init_ep0(vhub, &vhub->ep0, NULL);
 
 	/* Init devices */
-	for (i = 0; i < AST_VHUB_NUM_PORTS && rc == 0; i++)
+	for (i = 0; i < vhub->max_ports && rc == 0; i++)
 		rc = ast_vhub_init_dev(vhub, i);
 	if (rc)
 		goto err;
@@ -407,6 +423,9 @@ static const struct of_device_id ast_vhub_dt_ids[] = {
 	{
 		.compatible = "aspeed,ast2500-usb-vhub",
 	},
+	{
+		.compatible = "aspeed,ast2600-usb-vhub",
+	},
 	{ }
 };
 MODULE_DEVICE_TABLE(of, ast_vhub_dt_ids);
diff --git a/drivers/usb/gadget/udc/aspeed-vhub/dev.c b/drivers/usb/gadget/udc/aspeed-vhub/dev.c
index 4008e7a51188..d268306a7bfe 100644
--- a/drivers/usb/gadget/udc/aspeed-vhub/dev.c
+++ b/drivers/usb/gadget/udc/aspeed-vhub/dev.c
@@ -77,7 +77,7 @@ static void ast_vhub_dev_enable(struct ast_vhub_dev *d)
 	writel(d->ep0.buf_dma, d->regs + AST_VHUB_DEV_EP0_DATA);
 
 	/* Clear stall on all EPs */
-	for (i = 0; i < AST_VHUB_NUM_GEN_EPs; i++) {
+	for (i = 0; i < d->max_epns; i++) {
 		struct ast_vhub_ep *ep = d->epns[i];
 
 		if (ep && (ep->epn.stalled || ep->epn.wedged)) {
@@ -137,7 +137,7 @@ static int ast_vhub_ep_feature(struct ast_vhub_dev *d,
 	     is_set ? "SET" : "CLEAR", ep_num, wValue);
 	if (ep_num == 0)
 		return std_req_complete;
-	if (ep_num >= AST_VHUB_NUM_GEN_EPs || !d->epns[ep_num - 1])
+	if (ep_num >= d->max_epns || !d->epns[ep_num - 1])
 		return std_req_stall;
 	if (wValue != USB_ENDPOINT_HALT)
 		return std_req_driver;
@@ -181,7 +181,7 @@ static int ast_vhub_ep_status(struct ast_vhub_dev *d,
 
 	DDBG(d, "GET_STATUS(ep%d)\n", ep_num);
 
-	if (ep_num >= AST_VHUB_NUM_GEN_EPs)
+	if (ep_num >= d->max_epns)
 		return std_req_stall;
 	if (ep_num != 0) {
 		ep = d->epns[ep_num - 1];
@@ -299,7 +299,7 @@ static void ast_vhub_dev_nuke(struct ast_vhub_dev *d)
 {
 	unsigned int i;
 
-	for (i = 0; i < AST_VHUB_NUM_GEN_EPs; i++) {
+	for (i = 0; i < d->max_epns; i++) {
 		if (!d->epns[i])
 			continue;
 		ast_vhub_nuke(d->epns[i], -ESHUTDOWN);
@@ -416,10 +416,10 @@ static struct usb_ep *ast_vhub_udc_match_ep(struct usb_gadget *gadget,
 	 * that will allow the generic code to use our
 	 * assigned address.
 	 */
-	for (i = 0; i < AST_VHUB_NUM_GEN_EPs; i++)
+	for (i = 0; i < d->max_epns; i++)
 		if (d->epns[i] == NULL)
 			break;
-	if (i >= AST_VHUB_NUM_GEN_EPs)
+	if (i >= d->max_epns)
 		return NULL;
 	addr = i + 1;
 
@@ -526,6 +526,7 @@ void ast_vhub_del_dev(struct ast_vhub_dev *d)
 
 	usb_del_gadget_udc(&d->gadget);
 	device_unregister(d->port_dev);
+	kfree(d->epns);
 }
 
 static void ast_vhub_dev_release(struct device *dev)
@@ -547,13 +548,24 @@ int ast_vhub_init_dev(struct ast_vhub *vhub, unsigned int idx)
 	ast_vhub_init_ep0(vhub, &d->ep0, d);
 
 	/*
+	 * A USB device can have up to 30 endpoints besides control
+	 * endpoint 0.
+	 */
+	d->max_epns = min_t(u32, vhub->max_epns, 30);
+	d->epns = kcalloc(d->max_epns, sizeof(*d->epns), GFP_KERNEL);
+	if (!d->epns)
+		return -ENOMEM;
+
+	/*
 	 * The UDC core really needs us to have separate and uniquely
 	 * named "parent" devices for each port so we create a sub device
 	 * here for that purpose
 	 */
 	d->port_dev = kzalloc(sizeof(struct device), GFP_KERNEL);
-	if (!d->port_dev)
-		return -ENOMEM;
+	if (!d->port_dev) {
+		rc = -ENOMEM;
+		goto fail_alloc;
+	}
 	device_initialize(d->port_dev);
 	d->port_dev->release = ast_vhub_dev_release;
 	d->port_dev->parent = parent;
@@ -584,6 +596,8 @@ int ast_vhub_init_dev(struct ast_vhub *vhub, unsigned int idx)
 	device_del(d->port_dev);
  fail_add:
 	put_device(d->port_dev);
+ fail_alloc:
+	kfree(d->epns);
 
 	return rc;
 }
diff --git a/drivers/usb/gadget/udc/aspeed-vhub/epn.c b/drivers/usb/gadget/udc/aspeed-vhub/epn.c
index 7475c74aa5c5..0bd6b20435b8 100644
--- a/drivers/usb/gadget/udc/aspeed-vhub/epn.c
+++ b/drivers/usb/gadget/udc/aspeed-vhub/epn.c
@@ -800,10 +800,10 @@ struct ast_vhub_ep *ast_vhub_alloc_epn(struct ast_vhub_dev *d, u8 addr)
 
 	/* Find a free one (no device) */
 	spin_lock_irqsave(&vhub->lock, flags);
-	for (i = 0; i < AST_VHUB_NUM_GEN_EPs; i++)
+	for (i = 0; i < vhub->max_epns; i++)
 		if (vhub->epns[i].dev == NULL)
 			break;
-	if (i >= AST_VHUB_NUM_GEN_EPs) {
+	if (i >= vhub->max_epns) {
 		spin_unlock_irqrestore(&vhub->lock, flags);
 		return NULL;
 	}
diff --git a/drivers/usb/gadget/udc/aspeed-vhub/hub.c b/drivers/usb/gadget/udc/aspeed-vhub/hub.c
index 19b3517e04c0..6e565c3dbb5b 100644
--- a/drivers/usb/gadget/udc/aspeed-vhub/hub.c
+++ b/drivers/usb/gadget/udc/aspeed-vhub/hub.c
@@ -93,11 +93,7 @@ static void ast_vhub_patch_dev_desc_usb1(struct usb_device_descriptor *desc)
 				 USB_DT_INTERFACE_SIZE + \
 				 USB_DT_ENDPOINT_SIZE)
 
-static const struct ast_vhub_full_cdesc {
-	struct usb_config_descriptor	cfg;
-	struct usb_interface_descriptor intf;
-	struct usb_endpoint_descriptor	ep;
-} __attribute__ ((packed)) ast_vhub_conf_desc = {
+static const struct ast_vhub_full_cdesc ast_vhub_conf_desc = {
 	.cfg = {
 		.bLength		= USB_DT_CONFIG_SIZE,
 		.bDescriptorType	= USB_DT_CONFIG,
@@ -266,6 +262,7 @@ static int ast_vhub_rep_desc(struct ast_vhub_ep *ep,
 			     u8 desc_type, u16 len)
 {
 	size_t dsize;
+	struct ast_vhub *vhub = ep->vhub;
 
 	EPDBG(ep, "GET_DESCRIPTOR(type:%d)\n", desc_type);
 
@@ -281,20 +278,20 @@ static int ast_vhub_rep_desc(struct ast_vhub_ep *ep,
 	switch(desc_type) {
 	case USB_DT_DEVICE:
 		dsize = USB_DT_DEVICE_SIZE;
-		memcpy(ep->buf, &ast_vhub_dev_desc, dsize);
-		BUILD_BUG_ON(dsize > sizeof(ast_vhub_dev_desc));
+		memcpy(ep->buf, &vhub->vhub_dev_desc, dsize);
+		BUILD_BUG_ON(dsize > sizeof(vhub->vhub_dev_desc));
 		BUILD_BUG_ON(USB_DT_DEVICE_SIZE >= AST_VHUB_EP0_MAX_PACKET);
 		break;
 	case USB_DT_CONFIG:
 		dsize = AST_VHUB_CONF_DESC_SIZE;
-		memcpy(ep->buf, &ast_vhub_conf_desc, dsize);
-		BUILD_BUG_ON(dsize > sizeof(ast_vhub_conf_desc));
+		memcpy(ep->buf, &vhub->vhub_conf_desc, dsize);
+		BUILD_BUG_ON(dsize > sizeof(vhub->vhub_conf_desc));
 		BUILD_BUG_ON(AST_VHUB_CONF_DESC_SIZE >= AST_VHUB_EP0_MAX_PACKET);
 		break;
 	case USB_DT_HUB:
 		dsize = AST_VHUB_HUB_DESC_SIZE;
-		memcpy(ep->buf, &ast_vhub_hub_desc, dsize);
-		BUILD_BUG_ON(dsize > sizeof(ast_vhub_hub_desc));
+		memcpy(ep->buf, &vhub->vhub_hub_desc, dsize);
+		BUILD_BUG_ON(dsize > sizeof(vhub->vhub_hub_desc));
 		BUILD_BUG_ON(AST_VHUB_HUB_DESC_SIZE >= AST_VHUB_EP0_MAX_PACKET);
 		break;
 	default:
@@ -317,7 +314,8 @@ static int ast_vhub_rep_string(struct ast_vhub_ep *ep,
 			       u8 string_id, u16 lang_id,
 			       u16 len)
 {
-	int rc = usb_gadget_get_string (&ast_vhub_strings, string_id, ep->buf);
+	int rc = usb_gadget_get_string(&ep->vhub->vhub_str_desc,
+					string_id, ep->buf);
 
 	/*
 	 * This should never happen unless we put too big strings in
@@ -504,7 +502,7 @@ static void ast_vhub_wake_work(struct work_struct *work)
 	 * we let the normal host wake path deal with it later.
 	 */
 	spin_lock_irqsave(&vhub->lock, flags);
-	for (i = 0; i < AST_VHUB_NUM_PORTS; i++) {
+	for (i = 0; i < vhub->max_ports; i++) {
 		struct ast_vhub_port *p = &vhub->ports[i];
 
 		if (!(p->status & USB_PORT_STAT_SUSPEND))
@@ -587,7 +585,7 @@ static enum std_req_rc ast_vhub_set_port_feature(struct ast_vhub_ep *ep,
 	struct ast_vhub *vhub = ep->vhub;
 	struct ast_vhub_port *p;
 
-	if (port == 0 || port > AST_VHUB_NUM_PORTS)
+	if (port == 0 || port > vhub->max_ports)
 		return std_req_stall;
 	port--;
 	p = &vhub->ports[port];
@@ -630,7 +628,7 @@ static enum std_req_rc ast_vhub_clr_port_feature(struct ast_vhub_ep *ep,
 	struct ast_vhub *vhub = ep->vhub;
 	struct ast_vhub_port *p;
 
-	if (port == 0 || port > AST_VHUB_NUM_PORTS)
+	if (port == 0 || port > vhub->max_ports)
 		return std_req_stall;
 	port--;
 	p = &vhub->ports[port];
@@ -676,7 +674,7 @@ static enum std_req_rc ast_vhub_get_port_stat(struct ast_vhub_ep *ep,
 	struct ast_vhub *vhub = ep->vhub;
 	u16 stat, chg;
 
-	if (port == 0 || port > AST_VHUB_NUM_PORTS)
+	if (port == 0 || port > vhub->max_ports)
 		return std_req_stall;
 	port--;
 
@@ -757,7 +755,7 @@ void ast_vhub_hub_suspend(struct ast_vhub *vhub)
 	 * Forward to unsuspended ports without changing
 	 * their connection status.
 	 */
-	for (i = 0; i < AST_VHUB_NUM_PORTS; i++) {
+	for (i = 0; i < vhub->max_ports; i++) {
 		struct ast_vhub_port *p = &vhub->ports[i];
 
 		if (!(p->status & USB_PORT_STAT_SUSPEND))
@@ -780,7 +778,7 @@ void ast_vhub_hub_resume(struct ast_vhub *vhub)
 	 * Forward to unsuspended ports without changing
 	 * their connection status.
 	 */
-	for (i = 0; i < AST_VHUB_NUM_PORTS; i++) {
+	for (i = 0; i < vhub->max_ports; i++) {
 		struct ast_vhub_port *p = &vhub->ports[i];
 
 		if (!(p->status & USB_PORT_STAT_SUSPEND))
@@ -814,7 +812,7 @@ void ast_vhub_hub_reset(struct ast_vhub *vhub)
 	 * Clear all port status, disable gadgets and "suspend"
 	 * them. They will be woken up by a port reset.
 	 */
-	for (i = 0; i < AST_VHUB_NUM_PORTS; i++) {
+	for (i = 0; i < vhub->max_ports; i++) {
 		struct ast_vhub_port *p = &vhub->ports[i];
 
 		/* Only keep the connected flag */
@@ -834,9 +832,31 @@ void ast_vhub_hub_reset(struct ast_vhub *vhub)
 	writel(0, vhub->regs + AST_VHUB_EP1_STS_CHG);
 }
 
+static void ast_vhub_init_desc(struct ast_vhub *vhub)
+{
+	/* Initialize vhub Device Descriptor. */
+	memcpy(&vhub->vhub_dev_desc, &ast_vhub_dev_desc,
+		sizeof(vhub->vhub_dev_desc));
+
+	/* Initialize vhub Configuration Descriptor. */
+	memcpy(&vhub->vhub_conf_desc, &ast_vhub_conf_desc,
+		sizeof(vhub->vhub_conf_desc));
+
+	/* Initialize vhub Hub Descriptor. */
+	memcpy(&vhub->vhub_hub_desc, &ast_vhub_hub_desc,
+		sizeof(vhub->vhub_hub_desc));
+	vhub->vhub_hub_desc.bNbrPorts = vhub->max_ports;
+
+	/* Initialize vhub String Descriptors. */
+	memcpy(&vhub->vhub_str_desc, &ast_vhub_strings,
+		sizeof(vhub->vhub_str_desc));
+}
+
 void ast_vhub_init_hub(struct ast_vhub *vhub)
 {
 	vhub->speed = USB_SPEED_UNKNOWN;
 	INIT_WORK(&vhub->wake_work, ast_vhub_wake_work);
+
+	ast_vhub_init_desc(vhub);
 }
 
diff --git a/drivers/usb/gadget/udc/aspeed-vhub/vhub.h b/drivers/usb/gadget/udc/aspeed-vhub/vhub.h
index 761919e220d3..fac79ef6d669 100644
--- a/drivers/usb/gadget/udc/aspeed-vhub/vhub.h
+++ b/drivers/usb/gadget/udc/aspeed-vhub/vhub.h
@@ -2,6 +2,9 @@
 #ifndef __ASPEED_VHUB_H
 #define __ASPEED_VHUB_H
 
+#include <linux/usb.h>
+#include <linux/usb/ch11.h>
+
 /*****************************
  *                           *
  * VHUB register definitions *
@@ -76,17 +79,9 @@
 #define VHUB_SW_RESET_DEVICE2			(1 << 2)
 #define VHUB_SW_RESET_DEVICE1			(1 << 1)
 #define VHUB_SW_RESET_ROOT_HUB			(1 << 0)
-#define VHUB_SW_RESET_ALL			(VHUB_SW_RESET_EP_POOL | \
-						 VHUB_SW_RESET_DMA_CONTROLLER | \
-						 VHUB_SW_RESET_DEVICE5 | \
-						 VHUB_SW_RESET_DEVICE4 | \
-						 VHUB_SW_RESET_DEVICE3 | \
-						 VHUB_SW_RESET_DEVICE2 | \
-						 VHUB_SW_RESET_DEVICE1 | \
-						 VHUB_SW_RESET_ROOT_HUB)
+
 /* EP ACK/NACK IRQ masks */
 #define VHUB_EP_IRQ(n)				(1 << (n))
-#define VHUB_EP_IRQ_ALL				0x7fff	/* 15 EPs */
 
 /* USB status reg */
 #define VHUB_USBSTS_HISPEED			(1 << 27)
@@ -210,6 +205,11 @@
  *                                      *
  ****************************************/
 
+/*
+ * AST_VHUB_NUM_GEN_EPs and AST_VHUB_NUM_PORTS are kept to avoid breaking
+ * existing AST2400/AST2500 platforms. AST2600 and future vhub revisions
+ * should define number of downstream ports and endpoints in device tree.
+ */
 #define AST_VHUB_NUM_GEN_EPs	15	/* Generic non-0 EPs */
 #define AST_VHUB_NUM_PORTS	5	/* vHub ports */
 #define AST_VHUB_EP0_MAX_PACKET	64	/* EP0's max packet size */
@@ -312,7 +312,7 @@ struct ast_vhub_ep {
 			/* Registers */
 			void __iomem   		*regs;
 
-			/* Index in global pool (0..14) */
+			/* Index in global pool (zero-based) */
 			unsigned int		g_idx;
 
 			/* DMA Descriptors */
@@ -342,7 +342,7 @@ struct ast_vhub_dev {
 	struct ast_vhub			*vhub;
 	void __iomem			*regs;
 
-	/* Device index (0...4) and name string */
+	/* Device index (zero-based) and name string */
 	unsigned int			index;
 	const char			*name;
 
@@ -358,7 +358,8 @@ struct ast_vhub_dev {
 
 	/* Endpoint structures */
 	struct ast_vhub_ep		ep0;
-	struct ast_vhub_ep		*epns[AST_VHUB_NUM_GEN_EPs];
+	struct ast_vhub_ep		**epns;
+	u32				max_epns;
 
 };
 #define to_ast_dev(__g) container_of(__g, struct ast_vhub_dev, gadget)
@@ -373,6 +374,12 @@ struct ast_vhub_port {
 	struct ast_vhub_dev	dev;
 };
 
+struct ast_vhub_full_cdesc {
+	struct usb_config_descriptor	cfg;
+	struct usb_interface_descriptor intf;
+	struct usb_endpoint_descriptor	ep;
+} __packed;
+
 /* Global vhub structure */
 struct ast_vhub {
 	struct platform_device		*pdev;
@@ -393,10 +400,12 @@ struct ast_vhub {
 	bool				ep1_stalled : 1;
 
 	/* Per-port info */
-	struct ast_vhub_port		ports[AST_VHUB_NUM_PORTS];
+	struct ast_vhub_port		*ports;
+	u32				max_ports;
 
 	/* Generic EP data structures */
-	struct ast_vhub_ep		epns[AST_VHUB_NUM_GEN_EPs];
+	struct ast_vhub_ep		*epns;
+	u32				max_epns;
 
 	/* Upstream bus is suspended ? */
 	bool				suspended : 1;
@@ -409,6 +418,12 @@ struct ast_vhub {
 
 	/* Upstream bus speed captured at bus reset */
 	unsigned int			speed;
+
+	/* Standard USB Descriptors of the vhub. */
+	struct usb_device_descriptor	vhub_dev_desc;
+	struct ast_vhub_full_cdesc	vhub_conf_desc;
+	struct usb_hub_descriptor	vhub_hub_desc;
+	struct usb_gadget_strings	vhub_str_desc;
 };
 
 /* Standard request handlers result codes */
diff --git a/drivers/usb/gadget/udc/max3420_udc.c b/drivers/usb/gadget/udc/max3420_udc.c
new file mode 100644
index 000000000000..8fbc083b6732
--- /dev/null
+++ b/drivers/usb/gadget/udc/max3420_udc.c
@@ -0,0 +1,1331 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * MAX3420 Device Controller driver for USB.
+ *
+ * Author: Jaswinder Singh Brar <jaswinder.singh@linaro.org>
+ * (C) Copyright 2019-2020 Linaro Ltd
+ *
+ * Based on:
+ *	o MAX3420E datasheet
+ *		http://datasheets.maximintegrated.com/en/ds/MAX3420E.pdf
+ *	o MAX342{0,1}E Programming Guides
+ *		https://pdfserv.maximintegrated.com/en/an/AN3598.pdf
+ *		https://pdfserv.maximintegrated.com/en/an/AN3785.pdf
+ */
+
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/bitfield.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/of_platform.h>
+#include <linux/of_irq.h>
+#include <linux/prefetch.h>
+#include <linux/usb/ch9.h>
+#include <linux/usb/gadget.h>
+#include <linux/spi/spi.h>
+#include <linux/gpio/consumer.h>
+
+#define MAX3420_MAX_EPS		4
+#define MAX3420_EP_MAX_PACKET		64  /* Same for all Endpoints */
+#define MAX3420_EPNAME_SIZE		16  /* Buffer size for endpoint name */
+
+#define MAX3420_ACKSTAT		BIT(0)
+
+#define MAX3420_SPI_DIR_RD	0	/* read register from MAX3420 */
+#define MAX3420_SPI_DIR_WR	1	/* write register to MAX3420 */
+
+/* SPI commands: */
+#define MAX3420_SPI_DIR_SHIFT	1
+#define MAX3420_SPI_REG_SHIFT	3
+
+#define MAX3420_REG_EP0FIFO	0
+#define MAX3420_REG_EP1FIFO	1
+#define MAX3420_REG_EP2FIFO	2
+#define MAX3420_REG_EP3FIFO	3
+#define MAX3420_REG_SUDFIFO	4
+#define MAX3420_REG_EP0BC	5
+#define MAX3420_REG_EP1BC	6
+#define MAX3420_REG_EP2BC	7
+#define MAX3420_REG_EP3BC	8
+
+#define MAX3420_REG_EPSTALLS	9
+	#define ACKSTAT		BIT(6)
+	#define STLSTAT		BIT(5)
+	#define STLEP3IN	BIT(4)
+	#define STLEP2IN	BIT(3)
+	#define STLEP1OUT	BIT(2)
+	#define STLEP0OUT	BIT(1)
+	#define STLEP0IN	BIT(0)
+
+#define MAX3420_REG_CLRTOGS	10
+	#define EP3DISAB	BIT(7)
+	#define EP2DISAB	BIT(6)
+	#define EP1DISAB	BIT(5)
+	#define CTGEP3IN	BIT(4)
+	#define CTGEP2IN	BIT(3)
+	#define CTGEP1OUT	BIT(2)
+
+#define MAX3420_REG_EPIRQ	11
+#define MAX3420_REG_EPIEN	12
+	#define SUDAVIRQ	BIT(5)
+	#define IN3BAVIRQ	BIT(4)
+	#define IN2BAVIRQ	BIT(3)
+	#define OUT1DAVIRQ	BIT(2)
+	#define OUT0DAVIRQ	BIT(1)
+	#define IN0BAVIRQ	BIT(0)
+
+#define MAX3420_REG_USBIRQ	13
+#define MAX3420_REG_USBIEN	14
+	#define OSCOKIRQ	BIT(0)
+	#define RWUDNIRQ	BIT(1)
+	#define BUSACTIRQ	BIT(2)
+	#define URESIRQ		BIT(3)
+	#define SUSPIRQ		BIT(4)
+	#define NOVBUSIRQ	BIT(5)
+	#define VBUSIRQ		BIT(6)
+	#define URESDNIRQ	BIT(7)
+
+#define MAX3420_REG_USBCTL	15
+	#define HOSCSTEN	BIT(7)
+	#define VBGATE		BIT(6)
+	#define CHIPRES		BIT(5)
+	#define PWRDOWN		BIT(4)
+	#define CONNECT		BIT(3)
+	#define SIGRWU		BIT(2)
+
+#define MAX3420_REG_CPUCTL	16
+	#define IE		BIT(0)
+
+#define MAX3420_REG_PINCTL	17
+	#define EP3INAK		BIT(7)
+	#define EP2INAK		BIT(6)
+	#define EP0INAK		BIT(5)
+	#define FDUPSPI		BIT(4)
+	#define INTLEVEL	BIT(3)
+	#define POSINT		BIT(2)
+	#define GPXB		BIT(1)
+	#define GPXA		BIT(0)
+
+#define MAX3420_REG_REVISION	18
+
+#define MAX3420_REG_FNADDR	19
+	#define FNADDR_MASK	0x7f
+
+#define MAX3420_REG_IOPINS	20
+#define MAX3420_REG_IOPINS2	21
+#define MAX3420_REG_GPINIRQ	22
+#define MAX3420_REG_GPINIEN	23
+#define MAX3420_REG_GPINPOL	24
+#define MAX3420_REG_HIRQ	25
+#define MAX3420_REG_HIEN	26
+#define MAX3420_REG_MODE	27
+#define MAX3420_REG_PERADDR	28
+#define MAX3420_REG_HCTL	29
+#define MAX3420_REG_HXFR	30
+#define MAX3420_REG_HRSL	31
+
+#define ENABLE_IRQ	BIT(0)
+#define IOPIN_UPDATE	BIT(1)
+#define REMOTE_WAKEUP	BIT(2)
+#define CONNECT_HOST	GENMASK(4, 3)
+#define	HCONNECT	(1 << 3)
+#define	HDISCONNECT	(3 << 3)
+#define UDC_START	GENMASK(6, 5)
+#define	START		(1 << 5)
+#define	STOP		(3 << 5)
+#define ENABLE_EP	GENMASK(8, 7)
+#define	ENABLE		(1 << 7)
+#define	DISABLE		(3 << 7)
+#define STALL_EP	GENMASK(10, 9)
+#define	STALL		(1 << 9)
+#define	UNSTALL		(3 << 9)
+
+#define MAX3420_CMD(c)		FIELD_PREP(GENMASK(7, 3), c)
+#define MAX3420_SPI_CMD_RD(c)	(MAX3420_CMD(c) | (0 << 1))
+#define MAX3420_SPI_CMD_WR(c)	(MAX3420_CMD(c) | (1 << 1))
+
+struct max3420_req {
+	struct usb_request usb_req;
+	struct list_head queue;
+	struct max3420_ep *ep;
+};
+
+struct max3420_ep {
+	struct usb_ep ep_usb;
+	struct max3420_udc *udc;
+	struct list_head queue;
+	char name[MAX3420_EPNAME_SIZE];
+	unsigned int maxpacket;
+	spinlock_t lock;
+	int halted;
+	u32 todo;
+	int id;
+};
+
+struct max3420_udc {
+	struct usb_gadget gadget;
+	struct max3420_ep ep[MAX3420_MAX_EPS];
+	struct usb_gadget_driver *driver;
+	struct task_struct *thread_task;
+	int remote_wkp, is_selfpowered;
+	bool vbus_active, softconnect;
+	struct usb_ctrlrequest setup;
+	struct mutex spi_bus_mutex;
+	struct max3420_req ep0req;
+	struct spi_device *spi;
+	struct device *dev;
+	spinlock_t lock;
+	bool suspended;
+	u8 ep0buf[64];
+	u32 todo;
+};
+
+#define to_max3420_req(r)	container_of((r), struct max3420_req, usb_req)
+#define to_max3420_ep(e)	container_of((e), struct max3420_ep, ep_usb)
+#define to_udc(g)		container_of((g), struct max3420_udc, gadget)
+
+#define DRIVER_DESC     "MAX3420 USB Device-Mode Driver"
+static const char driver_name[] = "max3420-udc";
+
+/* Control endpoint configuration.*/
+static const struct usb_endpoint_descriptor ep0_desc = {
+	.bEndpointAddress	= USB_DIR_OUT,
+	.bmAttributes		= USB_ENDPOINT_XFER_CONTROL,
+	.wMaxPacketSize		= cpu_to_le16(MAX3420_EP_MAX_PACKET),
+};
+
+static void spi_ack_ctrl(struct max3420_udc *udc)
+{
+	struct spi_device *spi = udc->spi;
+	struct spi_transfer transfer;
+	struct spi_message msg;
+	u8 txdata[1];
+
+	memset(&transfer, 0, sizeof(transfer));
+
+	spi_message_init(&msg);
+
+	txdata[0] = MAX3420_ACKSTAT;
+	transfer.tx_buf = txdata;
+	transfer.len = 1;
+
+	spi_message_add_tail(&transfer, &msg);
+	spi_sync(spi, &msg);
+}
+
+static u8 spi_rd8_ack(struct max3420_udc *udc, u8 reg, int actstat)
+{
+	struct spi_device *spi = udc->spi;
+	struct spi_transfer transfer;
+	struct spi_message msg;
+	u8 txdata[2], rxdata[2];
+
+	memset(&transfer, 0, sizeof(transfer));
+
+	spi_message_init(&msg);
+
+	txdata[0] = MAX3420_SPI_CMD_RD(reg) | (actstat ? MAX3420_ACKSTAT : 0);
+	transfer.tx_buf = txdata;
+	transfer.rx_buf = rxdata;
+	transfer.len = 2;
+
+	spi_message_add_tail(&transfer, &msg);
+	spi_sync(spi, &msg);
+
+	return rxdata[1];
+}
+
+static u8 spi_rd8(struct max3420_udc *udc, u8 reg)
+{
+	return spi_rd8_ack(udc, reg, 0);
+}
+
+static void spi_wr8_ack(struct max3420_udc *udc, u8 reg, u8 val, int actstat)
+{
+	struct spi_device *spi = udc->spi;
+	struct spi_transfer transfer;
+	struct spi_message msg;
+	u8 txdata[2];
+
+	memset(&transfer, 0, sizeof(transfer));
+
+	spi_message_init(&msg);
+
+	txdata[0] = MAX3420_SPI_CMD_WR(reg) | (actstat ? MAX3420_ACKSTAT : 0);
+	txdata[1] = val;
+
+	transfer.tx_buf = txdata;
+	transfer.len = 2;
+
+	spi_message_add_tail(&transfer, &msg);
+	spi_sync(spi, &msg);
+}
+
+static void spi_wr8(struct max3420_udc *udc, u8 reg, u8 val)
+{
+	spi_wr8_ack(udc, reg, val, 0);
+}
+
+static void spi_rd_buf(struct max3420_udc *udc, u8 reg, void *buf, u8 len)
+{
+	struct spi_device *spi = udc->spi;
+	struct spi_transfer transfer;
+	struct spi_message msg;
+	u8 local_buf[MAX3420_EP_MAX_PACKET + 1] = {};
+
+	memset(&transfer, 0, sizeof(transfer));
+
+	spi_message_init(&msg);
+
+	local_buf[0] = MAX3420_SPI_CMD_RD(reg);
+	transfer.tx_buf = &local_buf[0];
+	transfer.rx_buf = &local_buf[0];
+	transfer.len = len + 1;
+
+	spi_message_add_tail(&transfer, &msg);
+	spi_sync(spi, &msg);
+
+	memcpy(buf, &local_buf[1], len);
+}
+
+static void spi_wr_buf(struct max3420_udc *udc, u8 reg, void *buf, u8 len)
+{
+	struct spi_device *spi = udc->spi;
+	struct spi_transfer transfer;
+	struct spi_message msg;
+	u8 local_buf[MAX3420_EP_MAX_PACKET + 1] = {};
+
+	memset(&transfer, 0, sizeof(transfer));
+
+	spi_message_init(&msg);
+
+	local_buf[0] = MAX3420_SPI_CMD_WR(reg);
+	memcpy(&local_buf[1], buf, len);
+
+	transfer.tx_buf = local_buf;
+	transfer.len = len + 1;
+
+	spi_message_add_tail(&transfer, &msg);
+	spi_sync(spi, &msg);
+}
+
+static int spi_max3420_enable(struct max3420_ep *ep)
+{
+	struct max3420_udc *udc = ep->udc;
+	unsigned long flags;
+	u8 epdis, epien;
+	int todo;
+
+	spin_lock_irqsave(&ep->lock, flags);
+	todo = ep->todo & ENABLE_EP;
+	ep->todo &= ~ENABLE_EP;
+	spin_unlock_irqrestore(&ep->lock, flags);
+
+	if (!todo || ep->id == 0)
+		return false;
+
+	epien = spi_rd8(udc, MAX3420_REG_EPIEN);
+	epdis = spi_rd8(udc, MAX3420_REG_CLRTOGS);
+
+	if (todo == ENABLE) {
+		epdis &= ~BIT(ep->id + 4);
+		epien |= BIT(ep->id + 1);
+	} else {
+		epdis |= BIT(ep->id + 4);
+		epien &= ~BIT(ep->id + 1);
+	}
+
+	spi_wr8(udc, MAX3420_REG_CLRTOGS, epdis);
+	spi_wr8(udc, MAX3420_REG_EPIEN, epien);
+
+	return true;
+}
+
+static int spi_max3420_stall(struct max3420_ep *ep)
+{
+	struct max3420_udc *udc = ep->udc;
+	unsigned long flags;
+	u8 epstalls;
+	int todo;
+
+	spin_lock_irqsave(&ep->lock, flags);
+	todo = ep->todo & STALL_EP;
+	ep->todo &= ~STALL_EP;
+	spin_unlock_irqrestore(&ep->lock, flags);
+
+	if (!todo || ep->id == 0)
+		return false;
+
+	epstalls = spi_rd8(udc, MAX3420_REG_EPSTALLS);
+	if (todo == STALL) {
+		ep->halted = 1;
+		epstalls |= BIT(ep->id + 1);
+	} else {
+		u8 clrtogs;
+
+		ep->halted = 0;
+		epstalls &= ~BIT(ep->id + 1);
+		clrtogs = spi_rd8(udc, MAX3420_REG_CLRTOGS);
+		clrtogs |= BIT(ep->id + 1);
+		spi_wr8(udc, MAX3420_REG_CLRTOGS, clrtogs);
+	}
+	spi_wr8(udc, MAX3420_REG_EPSTALLS, epstalls | ACKSTAT);
+
+	return true;
+}
+
+static int spi_max3420_rwkup(struct max3420_udc *udc)
+{
+	unsigned long flags;
+	int wake_remote;
+	u8 usbctl;
+
+	spin_lock_irqsave(&udc->lock, flags);
+	wake_remote = udc->todo & REMOTE_WAKEUP;
+	udc->todo &= ~REMOTE_WAKEUP;
+	spin_unlock_irqrestore(&udc->lock, flags);
+
+	if (!wake_remote || !udc->suspended)
+		return false;
+
+	/* Set Remote-WkUp Signal*/
+	usbctl = spi_rd8(udc, MAX3420_REG_USBCTL);
+	usbctl |= SIGRWU;
+	spi_wr8(udc, MAX3420_REG_USBCTL, usbctl);
+
+	msleep_interruptible(5);
+
+	/* Clear Remote-WkUp Signal*/
+	usbctl = spi_rd8(udc, MAX3420_REG_USBCTL);
+	usbctl &= ~SIGRWU;
+	spi_wr8(udc, MAX3420_REG_USBCTL, usbctl);
+
+	udc->suspended = false;
+
+	return true;
+}
+
+static void max3420_nuke(struct max3420_ep *ep, int status);
+static void __max3420_stop(struct max3420_udc *udc)
+{
+	u8 val;
+	int i;
+
+	/* clear all pending requests */
+	for (i = 1; i < MAX3420_MAX_EPS; i++)
+		max3420_nuke(&udc->ep[i], -ECONNRESET);
+
+	/* Disable IRQ to CPU */
+	spi_wr8(udc, MAX3420_REG_CPUCTL, 0);
+
+	val = spi_rd8(udc, MAX3420_REG_USBCTL);
+	val |= PWRDOWN;
+	if (udc->is_selfpowered)
+		val &= ~HOSCSTEN;
+	else
+		val |= HOSCSTEN;
+	spi_wr8(udc, MAX3420_REG_USBCTL, val);
+}
+
+static void __max3420_start(struct max3420_udc *udc)
+{
+	u8 val;
+
+	/* Need this delay if bus-powered,
+	 * but even for self-powered it helps stability
+	 */
+	msleep_interruptible(250);
+
+	/* configure SPI */
+	spi_wr8(udc, MAX3420_REG_PINCTL, FDUPSPI);
+
+	/* Chip Reset */
+	spi_wr8(udc, MAX3420_REG_USBCTL, CHIPRES);
+	msleep_interruptible(5);
+	spi_wr8(udc, MAX3420_REG_USBCTL, 0);
+
+	/* Poll for OSC to stabilize */
+	while (1) {
+		val = spi_rd8(udc, MAX3420_REG_USBIRQ);
+		if (val & OSCOKIRQ)
+			break;
+		cond_resched();
+	}
+
+	/* Enable PULL-UP only when Vbus detected */
+	val = spi_rd8(udc, MAX3420_REG_USBCTL);
+	val |= VBGATE | CONNECT;
+	spi_wr8(udc, MAX3420_REG_USBCTL, val);
+
+	val = URESDNIRQ | URESIRQ;
+	if (udc->is_selfpowered)
+		val |= NOVBUSIRQ;
+	spi_wr8(udc, MAX3420_REG_USBIEN, val);
+
+	/* Enable only EP0 interrupts */
+	val = IN0BAVIRQ | OUT0DAVIRQ | SUDAVIRQ;
+	spi_wr8(udc, MAX3420_REG_EPIEN, val);
+
+	/* Enable IRQ to CPU */
+	spi_wr8(udc, MAX3420_REG_CPUCTL, IE);
+}
+
+static int max3420_start(struct max3420_udc *udc)
+{
+	unsigned long flags;
+	int todo;
+
+	spin_lock_irqsave(&udc->lock, flags);
+	todo = udc->todo & UDC_START;
+	udc->todo &= ~UDC_START;
+	spin_unlock_irqrestore(&udc->lock, flags);
+
+	if (!todo)
+		return false;
+
+	if (udc->vbus_active && udc->softconnect)
+		__max3420_start(udc);
+	else
+		__max3420_stop(udc);
+
+	return true;
+}
+
+static irqreturn_t max3420_vbus_handler(int irq, void *dev_id)
+{
+	struct max3420_udc *udc = dev_id;
+	unsigned long flags;
+
+	spin_lock_irqsave(&udc->lock, flags);
+	/* its a vbus change interrupt */
+	udc->vbus_active = !udc->vbus_active;
+	udc->todo |= UDC_START;
+	usb_udc_vbus_handler(&udc->gadget, udc->vbus_active);
+	usb_gadget_set_state(&udc->gadget, udc->vbus_active
+			     ? USB_STATE_POWERED : USB_STATE_NOTATTACHED);
+	spin_unlock_irqrestore(&udc->lock, flags);
+
+	if (udc->thread_task &&
+	    udc->thread_task->state != TASK_RUNNING)
+		wake_up_process(udc->thread_task);
+
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t max3420_irq_handler(int irq, void *dev_id)
+{
+	struct max3420_udc *udc = dev_id;
+	struct spi_device *spi = udc->spi;
+	unsigned long flags;
+
+	spin_lock_irqsave(&udc->lock, flags);
+	if ((udc->todo & ENABLE_IRQ) == 0) {
+		disable_irq_nosync(spi->irq);
+		udc->todo |= ENABLE_IRQ;
+	}
+	spin_unlock_irqrestore(&udc->lock, flags);
+
+	if (udc->thread_task &&
+	    udc->thread_task->state != TASK_RUNNING)
+		wake_up_process(udc->thread_task);
+
+	return IRQ_HANDLED;
+}
+
+static void max3420_getstatus(struct max3420_udc *udc)
+{
+	struct max3420_ep *ep;
+	u16 status = 0;
+
+	switch (udc->setup.bRequestType & USB_RECIP_MASK) {
+	case USB_RECIP_DEVICE:
+		/* Get device status */
+		status = udc->gadget.is_selfpowered << USB_DEVICE_SELF_POWERED;
+		status |= (udc->remote_wkp << USB_DEVICE_REMOTE_WAKEUP);
+		break;
+	case USB_RECIP_INTERFACE:
+		if (udc->driver->setup(&udc->gadget, &udc->setup) < 0)
+			goto stall;
+		break;
+	case USB_RECIP_ENDPOINT:
+		ep = &udc->ep[udc->setup.wIndex & USB_ENDPOINT_NUMBER_MASK];
+		if (udc->setup.wIndex & USB_DIR_IN) {
+			if (!ep->ep_usb.caps.dir_in)
+				goto stall;
+		} else {
+			if (!ep->ep_usb.caps.dir_out)
+				goto stall;
+		}
+		if (ep->halted)
+			status = 1 << USB_ENDPOINT_HALT;
+		break;
+	default:
+		goto stall;
+	}
+
+	status = cpu_to_le16(status);
+	spi_wr_buf(udc, MAX3420_REG_EP0FIFO, &status, 2);
+	spi_wr8_ack(udc, MAX3420_REG_EP0BC, 2, 1);
+	return;
+stall:
+	dev_err(udc->dev, "Can't respond to getstatus request\n");
+	spi_wr8(udc, MAX3420_REG_EPSTALLS, STLEP0IN | STLEP0OUT | STLSTAT);
+}
+
+static void max3420_set_clear_feature(struct max3420_udc *udc)
+{
+	struct max3420_ep *ep;
+	int set = udc->setup.bRequest == USB_REQ_SET_FEATURE;
+	unsigned long flags;
+	int id;
+
+	switch (udc->setup.bRequestType) {
+	case USB_RECIP_DEVICE:
+		if (udc->setup.wValue != USB_DEVICE_REMOTE_WAKEUP)
+			break;
+
+		if (udc->setup.bRequest == USB_REQ_SET_FEATURE)
+			udc->remote_wkp = 1;
+		else
+			udc->remote_wkp = 0;
+
+		return spi_ack_ctrl(udc);
+
+	case USB_RECIP_ENDPOINT:
+		if (udc->setup.wValue != USB_ENDPOINT_HALT)
+			break;
+
+		id = udc->setup.wIndex & USB_ENDPOINT_NUMBER_MASK;
+		ep = &udc->ep[id];
+
+		spin_lock_irqsave(&ep->lock, flags);
+		ep->todo &= ~STALL_EP;
+		if (set)
+			ep->todo |= STALL;
+		else
+			ep->todo |= UNSTALL;
+		spin_unlock_irqrestore(&ep->lock, flags);
+
+		spi_max3420_stall(ep);
+		return;
+	default:
+		break;
+	}
+
+	dev_err(udc->dev, "Can't respond to SET/CLEAR FEATURE\n");
+	spi_wr8(udc, MAX3420_REG_EPSTALLS, STLEP0IN | STLEP0OUT | STLSTAT);
+}
+
+static void max3420_handle_setup(struct max3420_udc *udc)
+{
+	struct usb_ctrlrequest setup;
+	u8 addr;
+
+	spi_rd_buf(udc, MAX3420_REG_SUDFIFO, (void *)&setup, 8);
+
+	udc->setup = setup;
+	udc->setup.wValue = cpu_to_le16(setup.wValue);
+	udc->setup.wIndex = cpu_to_le16(setup.wIndex);
+	udc->setup.wLength = cpu_to_le16(setup.wLength);
+
+	switch (udc->setup.bRequest) {
+	case USB_REQ_GET_STATUS:
+		/* Data+Status phase form udc */
+		if ((udc->setup.bRequestType &
+				(USB_DIR_IN | USB_TYPE_MASK)) !=
+				(USB_DIR_IN | USB_TYPE_STANDARD)) {
+			break;
+		}
+		return max3420_getstatus(udc);
+	case USB_REQ_SET_ADDRESS:
+		/* Status phase from udc */
+		if (udc->setup.bRequestType != (USB_DIR_OUT |
+				USB_TYPE_STANDARD | USB_RECIP_DEVICE)) {
+			break;
+		}
+		addr = spi_rd8_ack(udc, MAX3420_REG_FNADDR, 1);
+		dev_dbg(udc->dev, "Assigned Address=%d\n", udc->setup.wValue);
+		return;
+	case USB_REQ_CLEAR_FEATURE:
+	case USB_REQ_SET_FEATURE:
+		/* Requests with no data phase, status phase from udc */
+		if ((udc->setup.bRequestType & USB_TYPE_MASK)
+				!= USB_TYPE_STANDARD)
+			break;
+		return max3420_set_clear_feature(udc);
+	default:
+		break;
+	}
+
+	if (udc->driver->setup(&udc->gadget, &setup) < 0) {
+		/* Stall EP0 */
+		spi_wr8(udc, MAX3420_REG_EPSTALLS,
+			STLEP0IN | STLEP0OUT | STLSTAT);
+	}
+}
+
+static void max3420_req_done(struct max3420_req *req, int status)
+{
+	struct max3420_ep *ep = req->ep;
+	struct max3420_udc *udc = ep->udc;
+
+	if (req->usb_req.status == -EINPROGRESS)
+		req->usb_req.status = status;
+	else
+		status = req->usb_req.status;
+
+	if (status && status != -ESHUTDOWN)
+		dev_err(udc->dev, "%s done %p, status %d\n",
+			ep->ep_usb.name, req, status);
+
+	if (req->usb_req.complete)
+		req->usb_req.complete(&ep->ep_usb, &req->usb_req);
+}
+
+static int max3420_do_data(struct max3420_udc *udc, int ep_id, int in)
+{
+	struct max3420_ep *ep = &udc->ep[ep_id];
+	struct max3420_req *req;
+	int done, length, psz;
+	void *buf;
+
+	if (list_empty(&ep->queue))
+		return false;
+
+	req = list_first_entry(&ep->queue, struct max3420_req, queue);
+	buf = req->usb_req.buf + req->usb_req.actual;
+
+	psz = ep->ep_usb.maxpacket;
+	length = req->usb_req.length - req->usb_req.actual;
+	length = min(length, psz);
+
+	if (length == 0) {
+		done = 1;
+		goto xfer_done;
+	}
+
+	done = 0;
+	if (in) {
+		prefetch(buf);
+		spi_wr_buf(udc, MAX3420_REG_EP0FIFO + ep_id, buf, length);
+		spi_wr8(udc, MAX3420_REG_EP0BC + ep_id, length);
+		if (length < psz)
+			done = 1;
+	} else {
+		psz = spi_rd8(udc, MAX3420_REG_EP0BC + ep_id);
+		length = min(length, psz);
+		prefetchw(buf);
+		spi_rd_buf(udc, MAX3420_REG_EP0FIFO + ep_id, buf, length);
+		if (length < ep->ep_usb.maxpacket)
+			done = 1;
+	}
+
+	req->usb_req.actual += length;
+
+	if (req->usb_req.actual == req->usb_req.length)
+		done = 1;
+
+xfer_done:
+	if (done) {
+		unsigned long flags;
+
+		spin_lock_irqsave(&ep->lock, flags);
+		list_del_init(&req->queue);
+		spin_unlock_irqrestore(&ep->lock, flags);
+
+		if (ep_id == 0)
+			spi_ack_ctrl(udc);
+
+		max3420_req_done(req, 0);
+	}
+
+	return true;
+}
+
+static int max3420_handle_irqs(struct max3420_udc *udc)
+{
+	u8 epien, epirq, usbirq, usbien, reg[4];
+	bool ret = false;
+
+	spi_rd_buf(udc, MAX3420_REG_EPIRQ, reg, 4);
+	epirq = reg[0];
+	epien = reg[1];
+	usbirq = reg[2];
+	usbien = reg[3];
+
+	usbirq &= usbien;
+	epirq &= epien;
+
+	if (epirq & SUDAVIRQ) {
+		spi_wr8(udc, MAX3420_REG_EPIRQ, SUDAVIRQ);
+		max3420_handle_setup(udc);
+		return true;
+	}
+
+	if (usbirq & VBUSIRQ) {
+		spi_wr8(udc, MAX3420_REG_USBIRQ, VBUSIRQ);
+		dev_dbg(udc->dev, "Cable plugged in\n");
+		return true;
+	}
+
+	if (usbirq & NOVBUSIRQ) {
+		spi_wr8(udc, MAX3420_REG_USBIRQ, NOVBUSIRQ);
+		dev_dbg(udc->dev, "Cable pulled out\n");
+		return true;
+	}
+
+	if (usbirq & URESIRQ) {
+		spi_wr8(udc, MAX3420_REG_USBIRQ, URESIRQ);
+		dev_dbg(udc->dev, "USB Reset - Start\n");
+		return true;
+	}
+
+	if (usbirq & URESDNIRQ) {
+		spi_wr8(udc, MAX3420_REG_USBIRQ, URESDNIRQ);
+		dev_dbg(udc->dev, "USB Reset - END\n");
+		spi_wr8(udc, MAX3420_REG_USBIEN, URESDNIRQ | URESIRQ);
+		spi_wr8(udc, MAX3420_REG_EPIEN, SUDAVIRQ | IN0BAVIRQ
+			| OUT0DAVIRQ);
+		return true;
+	}
+
+	if (usbirq & SUSPIRQ) {
+		spi_wr8(udc, MAX3420_REG_USBIRQ, SUSPIRQ);
+		dev_dbg(udc->dev, "USB Suspend - Enter\n");
+		udc->suspended = true;
+		return true;
+	}
+
+	if (usbirq & BUSACTIRQ) {
+		spi_wr8(udc, MAX3420_REG_USBIRQ, BUSACTIRQ);
+		dev_dbg(udc->dev, "USB Suspend - Exit\n");
+		udc->suspended = false;
+		return true;
+	}
+
+	if (usbirq & RWUDNIRQ) {
+		spi_wr8(udc, MAX3420_REG_USBIRQ, RWUDNIRQ);
+		dev_dbg(udc->dev, "Asked Host to wakeup\n");
+		return true;
+	}
+
+	if (usbirq & OSCOKIRQ) {
+		spi_wr8(udc, MAX3420_REG_USBIRQ, OSCOKIRQ);
+		dev_dbg(udc->dev, "Osc stabilized, start work\n");
+		return true;
+	}
+
+	if (epirq & OUT0DAVIRQ && max3420_do_data(udc, 0, 0)) {
+		spi_wr8_ack(udc, MAX3420_REG_EPIRQ, OUT0DAVIRQ, 1);
+		ret = true;
+	}
+
+	if (epirq & IN0BAVIRQ && max3420_do_data(udc, 0, 1))
+		ret = true;
+
+	if (epirq & OUT1DAVIRQ && max3420_do_data(udc, 1, 0)) {
+		spi_wr8_ack(udc, MAX3420_REG_EPIRQ, OUT1DAVIRQ, 1);
+		ret = true;
+	}
+
+	if (epirq & IN2BAVIRQ && max3420_do_data(udc, 2, 1))
+		ret = true;
+
+	if (epirq & IN3BAVIRQ && max3420_do_data(udc, 3, 1))
+		ret = true;
+
+	return ret;
+}
+
+static int max3420_thread(void *dev_id)
+{
+	struct max3420_udc *udc = dev_id;
+	struct spi_device *spi = udc->spi;
+	int i, loop_again = 1;
+	unsigned long flags;
+
+	while (!kthread_should_stop()) {
+		if (!loop_again) {
+			ktime_t kt = ns_to_ktime(1000 * 1000 * 250); /* 250ms */
+
+			set_current_state(TASK_INTERRUPTIBLE);
+
+			spin_lock_irqsave(&udc->lock, flags);
+			if (udc->todo & ENABLE_IRQ) {
+				enable_irq(spi->irq);
+				udc->todo &= ~ENABLE_IRQ;
+			}
+			spin_unlock_irqrestore(&udc->lock, flags);
+
+			schedule_hrtimeout(&kt, HRTIMER_MODE_REL);
+		}
+		loop_again = 0;
+
+		mutex_lock(&udc->spi_bus_mutex);
+
+		/* If bus-vbus_active and disconnected */
+		if (!udc->vbus_active || !udc->softconnect)
+			goto loop;
+
+		if (max3420_start(udc)) {
+			loop_again = 1;
+			goto loop;
+		}
+
+		if (max3420_handle_irqs(udc)) {
+			loop_again = 1;
+			goto loop;
+		}
+
+		if (spi_max3420_rwkup(udc)) {
+			loop_again = 1;
+			goto loop;
+		}
+
+		max3420_do_data(udc, 0, 1); /* get done with the EP0 ZLP */
+
+		for (i = 1; i < MAX3420_MAX_EPS; i++) {
+			struct max3420_ep *ep = &udc->ep[i];
+
+			if (spi_max3420_enable(ep))
+				loop_again = 1;
+			if (spi_max3420_stall(ep))
+				loop_again = 1;
+		}
+loop:
+		mutex_unlock(&udc->spi_bus_mutex);
+	}
+
+	set_current_state(TASK_RUNNING);
+	dev_info(udc->dev, "SPI thread exiting");
+	return 0;
+}
+
+static int max3420_ep_set_halt(struct usb_ep *_ep, int stall)
+{
+	struct max3420_ep *ep = to_max3420_ep(_ep);
+	struct max3420_udc *udc = ep->udc;
+	unsigned long flags;
+
+	spin_lock_irqsave(&ep->lock, flags);
+
+	ep->todo &= ~STALL_EP;
+	if (stall)
+		ep->todo |= STALL;
+	else
+		ep->todo |= UNSTALL;
+
+	spin_unlock_irqrestore(&ep->lock, flags);
+
+	wake_up_process(udc->thread_task);
+
+	dev_dbg(udc->dev, "%sStall %s\n", stall ? "" : "Un", ep->name);
+	return 0;
+}
+
+static int __max3420_ep_enable(struct max3420_ep *ep,
+			       const struct usb_endpoint_descriptor *desc)
+{
+	unsigned int maxp = usb_endpoint_maxp(desc);
+	unsigned long flags;
+
+	spin_lock_irqsave(&ep->lock, flags);
+	ep->ep_usb.desc = desc;
+	ep->ep_usb.maxpacket = maxp;
+
+	ep->todo &= ~ENABLE_EP;
+	ep->todo |= ENABLE;
+	spin_unlock_irqrestore(&ep->lock, flags);
+
+	return 0;
+}
+
+static int max3420_ep_enable(struct usb_ep *_ep,
+			     const struct usb_endpoint_descriptor *desc)
+{
+	struct max3420_ep *ep = to_max3420_ep(_ep);
+	struct max3420_udc *udc = ep->udc;
+
+	__max3420_ep_enable(ep, desc);
+
+	wake_up_process(udc->thread_task);
+
+	return 0;
+}
+
+static void max3420_nuke(struct max3420_ep *ep, int status)
+{
+	struct max3420_req *req, *r;
+	unsigned long flags;
+
+	spin_lock_irqsave(&ep->lock, flags);
+
+	list_for_each_entry_safe(req, r, &ep->queue, queue) {
+		list_del_init(&req->queue);
+
+		spin_unlock_irqrestore(&ep->lock, flags);
+		max3420_req_done(req, status);
+		spin_lock_irqsave(&ep->lock, flags);
+	}
+
+	spin_unlock_irqrestore(&ep->lock, flags);
+}
+
+static void __max3420_ep_disable(struct max3420_ep *ep)
+{
+	struct max3420_udc *udc = ep->udc;
+	unsigned long flags;
+
+	spin_lock_irqsave(&ep->lock, flags);
+
+	ep->ep_usb.desc = NULL;
+
+	ep->todo &= ~ENABLE_EP;
+	ep->todo |= DISABLE;
+
+	spin_unlock_irqrestore(&ep->lock, flags);
+
+	dev_dbg(udc->dev, "Disabled %s\n", ep->name);
+}
+
+static int max3420_ep_disable(struct usb_ep *_ep)
+{
+	struct max3420_ep *ep = to_max3420_ep(_ep);
+	struct max3420_udc *udc = ep->udc;
+
+	max3420_nuke(ep, -ESHUTDOWN);
+
+	__max3420_ep_disable(ep);
+
+	wake_up_process(udc->thread_task);
+
+	return 0;
+}
+
+static struct usb_request *max3420_alloc_request(struct usb_ep *_ep,
+						 gfp_t gfp_flags)
+{
+	struct max3420_ep *ep = to_max3420_ep(_ep);
+	struct max3420_req *req;
+
+	req = kzalloc(sizeof(*req), gfp_flags);
+	if (!req)
+		return NULL;
+
+	req->ep = ep;
+
+	return &req->usb_req;
+}
+
+static void max3420_free_request(struct usb_ep *_ep, struct usb_request *_req)
+{
+	kfree(to_max3420_req(_req));
+}
+
+static int max3420_ep_queue(struct usb_ep *_ep, struct usb_request *_req,
+			    gfp_t ignored)
+{
+	struct max3420_req *req = to_max3420_req(_req);
+	struct max3420_ep *ep  = to_max3420_ep(_ep);
+	struct max3420_udc *udc = ep->udc;
+	unsigned long flags;
+
+	_req->status = -EINPROGRESS;
+	_req->actual = 0;
+
+	spin_lock_irqsave(&ep->lock, flags);
+	list_add_tail(&req->queue, &ep->queue);
+	spin_unlock_irqrestore(&ep->lock, flags);
+
+	wake_up_process(udc->thread_task);
+	return 0;
+}
+
+static int max3420_ep_dequeue(struct usb_ep *_ep, struct usb_request *_req)
+{
+	struct max3420_req *t, *req = to_max3420_req(_req);
+	struct max3420_ep *ep = to_max3420_ep(_ep);
+	unsigned long flags;
+
+	spin_lock_irqsave(&ep->lock, flags);
+
+	/* Pluck the descriptor from queue */
+	list_for_each_entry(t, &ep->queue, queue)
+		if (t == req) {
+			list_del_init(&req->queue);
+			break;
+		}
+
+	spin_unlock_irqrestore(&ep->lock, flags);
+
+	if (t == req)
+		max3420_req_done(req, -ECONNRESET);
+
+	return 0;
+}
+
+static const struct usb_ep_ops max3420_ep_ops = {
+	.enable		= max3420_ep_enable,
+	.disable	= max3420_ep_disable,
+	.alloc_request	= max3420_alloc_request,
+	.free_request	= max3420_free_request,
+	.queue		= max3420_ep_queue,
+	.dequeue	= max3420_ep_dequeue,
+	.set_halt	= max3420_ep_set_halt,
+};
+
+static int max3420_wakeup(struct usb_gadget *gadget)
+{
+	struct max3420_udc *udc = to_udc(gadget);
+	unsigned long flags;
+	int ret = -EINVAL;
+
+	spin_lock_irqsave(&udc->lock, flags);
+
+	/* Only if wakeup allowed by host */
+	if (udc->remote_wkp) {
+		udc->todo |= REMOTE_WAKEUP;
+		ret = 0;
+	}
+
+	spin_unlock_irqrestore(&udc->lock, flags);
+
+	if (udc->thread_task &&
+	    udc->thread_task->state != TASK_RUNNING)
+		wake_up_process(udc->thread_task);
+	return ret;
+}
+
+static int max3420_udc_start(struct usb_gadget *gadget,
+			     struct usb_gadget_driver *driver)
+{
+	struct max3420_udc *udc = to_udc(gadget);
+	unsigned long flags;
+
+	spin_lock_irqsave(&udc->lock, flags);
+	/* hook up the driver */
+	driver->driver.bus = NULL;
+	udc->driver = driver;
+	udc->gadget.speed = USB_SPEED_FULL;
+
+	udc->gadget.is_selfpowered = udc->is_selfpowered;
+	udc->remote_wkp = 0;
+	udc->softconnect = true;
+	udc->todo |= UDC_START;
+	spin_unlock_irqrestore(&udc->lock, flags);
+
+	if (udc->thread_task &&
+	    udc->thread_task->state != TASK_RUNNING)
+		wake_up_process(udc->thread_task);
+
+	return 0;
+}
+
+static int max3420_udc_stop(struct usb_gadget *gadget)
+{
+	struct max3420_udc *udc = to_udc(gadget);
+	unsigned long flags;
+
+	spin_lock_irqsave(&udc->lock, flags);
+	udc->is_selfpowered = udc->gadget.is_selfpowered;
+	udc->gadget.speed = USB_SPEED_UNKNOWN;
+	udc->driver = NULL;
+	udc->softconnect = false;
+	udc->todo |= UDC_START;
+	spin_unlock_irqrestore(&udc->lock, flags);
+
+	if (udc->thread_task &&
+	    udc->thread_task->state != TASK_RUNNING)
+		wake_up_process(udc->thread_task);
+
+	return 0;
+}
+
+static const struct usb_gadget_ops max3420_udc_ops = {
+	.udc_start	= max3420_udc_start,
+	.udc_stop	= max3420_udc_stop,
+	.wakeup		= max3420_wakeup,
+};
+
+static void max3420_eps_init(struct max3420_udc *udc)
+{
+	int idx;
+
+	INIT_LIST_HEAD(&udc->gadget.ep_list);
+
+	for (idx = 0; idx < MAX3420_MAX_EPS; idx++) {
+		struct max3420_ep *ep = &udc->ep[idx];
+
+		spin_lock_init(&ep->lock);
+		INIT_LIST_HEAD(&ep->queue);
+
+		ep->udc = udc;
+		ep->id = idx;
+		ep->halted = 0;
+		ep->maxpacket = 0;
+		ep->ep_usb.name = ep->name;
+		ep->ep_usb.ops = &max3420_ep_ops;
+		usb_ep_set_maxpacket_limit(&ep->ep_usb, MAX3420_EP_MAX_PACKET);
+
+		if (idx == 0) { /* For EP0 */
+			ep->ep_usb.desc = &ep0_desc;
+			ep->ep_usb.maxpacket = usb_endpoint_maxp(&ep0_desc);
+			ep->ep_usb.caps.type_control = true;
+			ep->ep_usb.caps.dir_in = true;
+			ep->ep_usb.caps.dir_out = true;
+			snprintf(ep->name, MAX3420_EPNAME_SIZE, "ep0");
+			continue;
+		}
+
+		if (idx == 1) { /* EP1 is OUT */
+			ep->ep_usb.caps.dir_in = false;
+			ep->ep_usb.caps.dir_out = true;
+			snprintf(ep->name, MAX3420_EPNAME_SIZE, "ep1-bulk-out");
+		} else { /* EP2 & EP3 are IN */
+			ep->ep_usb.caps.dir_in = true;
+			ep->ep_usb.caps.dir_out = false;
+			snprintf(ep->name, MAX3420_EPNAME_SIZE,
+				 "ep%d-bulk-in", idx);
+		}
+		ep->ep_usb.caps.type_iso = false;
+		ep->ep_usb.caps.type_int = false;
+		ep->ep_usb.caps.type_bulk = true;
+
+		list_add_tail(&ep->ep_usb.ep_list,
+			      &udc->gadget.ep_list);
+	}
+}
+
+static int max3420_probe(struct spi_device *spi)
+{
+	struct max3420_udc *udc;
+	int err, irq;
+	u8 reg[8];
+
+	if (spi->master->flags & SPI_MASTER_HALF_DUPLEX) {
+		dev_err(&spi->dev, "UDC needs full duplex to work\n");
+		return -EINVAL;
+	}
+
+	spi->mode = SPI_MODE_3;
+	spi->bits_per_word = 8;
+
+	err = spi_setup(spi);
+	if (err) {
+		dev_err(&spi->dev, "Unable to setup SPI bus\n");
+		return -EFAULT;
+	}
+
+	udc = devm_kzalloc(&spi->dev, sizeof(*udc), GFP_KERNEL);
+	if (!udc)
+		return -ENOMEM;
+
+	udc->spi = spi;
+
+	udc->remote_wkp = 0;
+
+	/* Setup gadget structure */
+	udc->gadget.ops = &max3420_udc_ops;
+	udc->gadget.max_speed = USB_SPEED_FULL;
+	udc->gadget.speed = USB_SPEED_UNKNOWN;
+	udc->gadget.ep0 = &udc->ep[0].ep_usb;
+	udc->gadget.name = driver_name;
+
+	spin_lock_init(&udc->lock);
+	mutex_init(&udc->spi_bus_mutex);
+
+	udc->ep0req.ep = &udc->ep[0];
+	udc->ep0req.usb_req.buf = udc->ep0buf;
+	INIT_LIST_HEAD(&udc->ep0req.queue);
+
+	/* setup Endpoints */
+	max3420_eps_init(udc);
+
+	/* configure SPI */
+	spi_rd_buf(udc, MAX3420_REG_EPIRQ, reg, 8);
+	spi_wr8(udc, MAX3420_REG_PINCTL, FDUPSPI);
+
+	err = usb_add_gadget_udc(&spi->dev, &udc->gadget);
+	if (err)
+		return err;
+
+	udc->dev = &udc->gadget.dev;
+
+	spi_set_drvdata(spi, udc);
+
+	irq = of_irq_get_byname(spi->dev.of_node, "udc");
+	err = devm_request_irq(&spi->dev, irq, max3420_irq_handler, 0,
+			       "max3420", udc);
+	if (err < 0)
+		return err;
+
+	udc->thread_task = kthread_create(max3420_thread, udc,
+					  "max3420-thread");
+	if (IS_ERR(udc->thread_task))
+		return PTR_ERR(udc->thread_task);
+
+	irq = of_irq_get_byname(spi->dev.of_node, "vbus");
+	if (irq <= 0) { /* no vbus irq implies self-powered design */
+		udc->is_selfpowered = 1;
+		udc->vbus_active = true;
+		udc->todo |= UDC_START;
+		usb_udc_vbus_handler(&udc->gadget, udc->vbus_active);
+		usb_gadget_set_state(&udc->gadget, USB_STATE_POWERED);
+		max3420_start(udc);
+	} else {
+		udc->is_selfpowered = 0;
+		/* Detect current vbus status */
+		spi_rd_buf(udc, MAX3420_REG_EPIRQ, reg, 8);
+		if (reg[7] != 0xff)
+			udc->vbus_active = true;
+
+		err = devm_request_irq(&spi->dev, irq,
+				       max3420_vbus_handler, 0, "vbus", udc);
+		if (err < 0)
+			return err;
+	}
+
+	return 0;
+}
+
+static int max3420_remove(struct spi_device *spi)
+{
+	struct max3420_udc *udc = spi_get_drvdata(spi);
+	unsigned long flags;
+
+	usb_del_gadget_udc(&udc->gadget);
+
+	spin_lock_irqsave(&udc->lock, flags);
+
+	kthread_stop(udc->thread_task);
+
+	spin_unlock_irqrestore(&udc->lock, flags);
+
+	return 0;
+}
+
+static const struct of_device_id max3420_udc_of_match[] = {
+	{ .compatible = "maxim,max3420-udc"},
+	{ .compatible = "maxim,max3421-udc"},
+	{},
+};
+MODULE_DEVICE_TABLE(of, max3420_udc_of_match);
+
+static struct spi_driver max3420_driver = {
+	.driver = {
+		.name = "max3420-udc",
+		.of_match_table = of_match_ptr(max3420_udc_of_match),
+	},
+	.probe = max3420_probe,
+	.remove = max3420_remove,
+};
+
+module_spi_driver(max3420_driver);
+
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_AUTHOR("Jassi Brar <jaswinder.singh@linaro.org>");
+MODULE_LICENSE("GPL");
diff --git a/drivers/usb/gadget/udc/tegra-xudc.c b/drivers/usb/gadget/udc/tegra-xudc.c
index b9df6369d56d..09eb64e9889a 100644
--- a/drivers/usb/gadget/udc/tegra-xudc.c
+++ b/drivers/usb/gadget/udc/tegra-xudc.c
@@ -3493,11 +3493,8 @@ static int tegra_xudc_probe(struct platform_device *pdev)
 	}
 
 	xudc->irq = platform_get_irq(pdev, 0);
-	if (xudc->irq < 0) {
-		dev_err(xudc->dev, "failed to get IRQ: %d\n",
-				xudc->irq);
+	if (xudc->irq < 0)
 		return xudc->irq;
-	}
 
 	err = devm_request_irq(&pdev->dev, xudc->irq, tegra_xudc_irq, 0,
 			       dev_name(&pdev->dev), xudc);