USB: gadget: add atmel usba udc driver

Add atmel usba udc driver support, porting from Linux kernel

The original code in Linux Kernel information is as following

commit e01ee9f509a927158f670408b41127d4166db1c7
Author: Jingoo Han <jg1.han@samsung.com>
Date:   Tue Jul 30 17:00:51 2013 +0900

    usb: gadget: use dev_get_platdata()

    Use the wrapper function for retrieving the platform data instead of
    accessing dev->platform_data directly.

Signed-off-by: Bo Shen <voice.shen@atmel.com>

5 files changed, 1722 insertions, 0 deletions

diff --git a/arch/arm/include/asm/arch-at91/atmel_usba_udc.h b/arch/arm/include/asm/arch-at91/atmel_usba_udc.h
new file mode 100644
index 0000000..6f540d2
--- /dev/null
+++ b/arch/arm/include/asm/arch-at91/atmel_usba_udc.h
@@ -0,0 +1,64 @@
+/*
+ * Copyright (C) 2005-2013 Atmel Corporation
+ *			   Bo Shen <voice.shen@atmel.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#ifndef __ATMEL_USBA_UDC_H__
+#define __ATMEL_USBA_UDC_H__
+
+#include <linux/usb/atmel_usba_udc.h>
+
+#define EP(nam, idx, maxpkt, maxbk, dma, isoc)		\
+	[idx] = {					\
+		.name	= nam,				\
+		.index	= idx,				\
+		.fifo_size	= maxpkt,		\
+		.nr_banks	= maxbk,		\
+		.can_dma	= dma,			\
+		.can_isoc	= isoc,			\
+	}
+
+#if defined(CONFIG_AT91SAM9G45) || defined(CONFIG_AT91SAM9M10G45) || \
+	defined(CONFIG_AT91SAM9X5)
+static struct usba_ep_data usba_udc_ep[] = {
+	EP("ep0", 0, 64, 1, 0, 0),
+	EP("ep1", 1, 1024, 2, 1, 1),
+	EP("ep2", 2, 1024, 2, 1, 1),
+	EP("ep3", 3, 1024, 3, 1, 0),
+	EP("ep4", 4, 1024, 3, 1, 0),
+	EP("ep5", 5, 1024, 3, 1, 1),
+	EP("ep6", 6, 1024, 3, 1, 1),
+};
+#elif defined(CONFIG_SAMA5D3)
+static struct usba_ep_data usba_udc_ep[] = {
+	EP("ep0", 0, 64, 1, 0, 0),
+	EP("ep1", 1, 1024, 3, 1, 0),
+	EP("ep2", 2, 1024, 3, 1, 0),
+	EP("ep3", 3, 1024, 2, 1, 0),
+	EP("ep4", 4, 1024, 2, 1, 0),
+	EP("ep5", 5, 1024, 2, 1, 0),
+	EP("ep6", 6, 1024, 2, 1, 0),
+	EP("ep7", 7, 1024, 2, 1, 0),
+	EP("ep8", 8, 1024, 2, 0, 0),
+	EP("ep9", 9, 1024, 2, 0, 0),
+	EP("ep10", 10, 1024, 2, 0, 0),
+	EP("ep11", 11, 1024, 2, 0, 0),
+	EP("ep12", 12, 1024, 2, 0, 0),
+	EP("ep13", 13, 1024, 2, 0, 0),
+	EP("ep14", 14, 1024, 2, 0, 0),
+	EP("ep15", 15, 1024, 2, 0, 0),
+};
+#else
+# error "NO usba_udc_ep defined"
+#endif
+
+#undef EP
+
+struct usba_platform_data pdata = {
+	.num_ep	= ARRAY_SIZE(usba_udc_ep),
+	.ep	= usba_udc_ep,
+};
+
+#endif
diff --git a/drivers/usb/gadget/Makefile b/drivers/usb/gadget/Makefile
index 4c2a39a..4d51f59 100644
--- a/drivers/usb/gadget/Makefile
+++ b/drivers/usb/gadget/Makefile
@@ -18,6 +18,7 @@ endif
 
 # new USB gadget layer dependencies
 ifdef CONFIG_USB_GADGET
+COBJS-$(CONFIG_USB_GADGET_ATMEL_USBA) += atmel_usba_udc.o
 COBJS-$(CONFIG_USB_GADGET_S3C_UDC_OTG) += s3c_udc_otg.o
 COBJS-$(CONFIG_USB_GADGET_FOTG210) += fotg210.o
 COBJS-$(CONFIG_USBDOWNLOAD_GADGET) += g_dnl.o
diff --git a/drivers/usb/gadget/atmel_usba_udc.c b/drivers/usb/gadget/atmel_usba_udc.c
new file mode 100644
index 0000000..f146c48
--- /dev/null
+++ b/drivers/usb/gadget/atmel_usba_udc.c
@@ -0,0 +1,1305 @@
+/*
+ * Driver for the Atmel USBA high speed USB device controller
+ * [Original from Linux kernel: drivers/usb/gadget/atmel_usba_udc.c]
+ *
+ * Copyright (C) 2005-2013 Atmel Corporation
+ *			   Bo Shen <voice.shen@atmel.com>
+ *
+ * SPDX-License-Identifier:     GPL-2.0+
+ */
+
+#include <common.h>
+#include <asm/errno.h>
+#include <asm/gpio.h>
+#include <asm/hardware.h>
+#include <linux/list.h>
+#include <linux/usb/ch9.h>
+#include <linux/usb/gadget.h>
+#include <linux/usb/atmel_usba_udc.h>
+#include <malloc.h>
+#include <usb/lin_gadget_compat.h>
+
+#include "atmel_usba_udc.h"
+
+static int vbus_is_present(struct usba_udc *udc)
+{
+	/* No Vbus detection: Assume always present */
+	return 1;
+}
+
+static void next_fifo_transaction(struct usba_ep *ep, struct usba_request *req)
+{
+	unsigned int transaction_len;
+
+	transaction_len = req->req.length - req->req.actual;
+	req->last_transaction = 1;
+	if (transaction_len > ep->ep.maxpacket) {
+		transaction_len = ep->ep.maxpacket;
+		req->last_transaction = 0;
+	} else if (transaction_len == ep->ep.maxpacket && req->req.zero) {
+			req->last_transaction = 0;
+	}
+
+	DBG(DBG_QUEUE, "%s: submit_transaction, req %p (length %d)%s\n",
+	    ep->ep.name, req, transaction_len,
+	    req->last_transaction ? ", done" : "");
+
+	memcpy(ep->fifo, req->req.buf + req->req.actual, transaction_len);
+	usba_ep_writel(ep, SET_STA, USBA_TX_PK_RDY);
+	req->req.actual += transaction_len;
+}
+
+static void submit_request(struct usba_ep *ep, struct usba_request *req)
+{
+	DBG(DBG_QUEUE, "%s: submit_request: req %p (length %d), dma: %d\n",
+	    ep->ep.name, req, req->req.length, req->using_dma);
+
+	req->req.actual = 0;
+	req->submitted = 1;
+
+	next_fifo_transaction(ep, req);
+	if (req->last_transaction) {
+		usba_ep_writel(ep, CTL_DIS, USBA_TX_PK_RDY);
+		usba_ep_writel(ep, CTL_ENB, USBA_TX_COMPLETE);
+	} else {
+		usba_ep_writel(ep, CTL_DIS, USBA_TX_COMPLETE);
+		usba_ep_writel(ep, CTL_ENB, USBA_TX_PK_RDY);
+	}
+}
+
+static void submit_next_request(struct usba_ep *ep)
+{
+	struct usba_request *req;
+
+	if (list_empty(&ep->queue)) {
+		usba_ep_writel(ep, CTL_DIS, USBA_TX_PK_RDY | USBA_RX_BK_RDY);
+		return;
+	}
+
+	req = list_entry(ep->queue.next, struct usba_request, queue);
+	if (!req->submitted)
+		submit_request(ep, req);
+}
+
+static void send_status(struct usba_udc *udc, struct usba_ep *ep)
+{
+	ep->state = STATUS_STAGE_IN;
+	usba_ep_writel(ep, SET_STA, USBA_TX_PK_RDY);
+	usba_ep_writel(ep, CTL_ENB, USBA_TX_COMPLETE);
+}
+
+static void receive_data(struct usba_ep *ep)
+{
+	struct usba_udc *udc = ep->udc;
+	struct usba_request *req;
+	unsigned long status;
+	unsigned int bytecount, nr_busy;
+	int is_complete = 0;
+
+	status = usba_ep_readl(ep, STA);
+	nr_busy = USBA_BFEXT(BUSY_BANKS, status);
+
+	DBG(DBG_QUEUE, "receive data: nr_busy=%u\n", nr_busy);
+
+	while (nr_busy > 0) {
+		if (list_empty(&ep->queue)) {
+			usba_ep_writel(ep, CTL_DIS, USBA_RX_BK_RDY);
+			break;
+		}
+		req = list_entry(ep->queue.next,
+				 struct usba_request, queue);
+
+		bytecount = USBA_BFEXT(BYTE_COUNT, status);
+
+		if (status & USBA_SHORT_PACKET)
+			is_complete = 1;
+		if (req->req.actual + bytecount >= req->req.length) {
+			is_complete = 1;
+			bytecount = req->req.length - req->req.actual;
+		}
+
+		memcpy(req->req.buf + req->req.actual, ep->fifo, bytecount);
+		req->req.actual += bytecount;
+
+		usba_ep_writel(ep, CLR_STA, USBA_RX_BK_RDY);
+
+		if (is_complete) {
+			DBG(DBG_QUEUE, "%s: request done\n", ep->ep.name);
+			req->req.status = 0;
+			list_del_init(&req->queue);
+			usba_ep_writel(ep, CTL_DIS, USBA_RX_BK_RDY);
+			spin_lock(&udc->lock);
+			req->req.complete(&ep->ep, &req->req);
+			spin_unlock(&udc->lock);
+		}
+
+		status = usba_ep_readl(ep, STA);
+		nr_busy = USBA_BFEXT(BUSY_BANKS, status);
+
+		if (is_complete && ep_is_control(ep)) {
+			send_status(udc, ep);
+			break;
+		}
+	}
+}
+
+static void
+request_complete(struct usba_ep *ep, struct usba_request *req, int status)
+{
+	if (req->req.status == -EINPROGRESS)
+		req->req.status = status;
+
+	DBG(DBG_GADGET | DBG_REQ, "%s: req %p complete: status %d, actual %u\n",
+	    ep->ep.name, req, req->req.status, req->req.actual);
+
+	req->req.complete(&ep->ep, &req->req);
+}
+
+static void
+request_complete_list(struct usba_ep *ep, struct list_head *list, int status)
+{
+	struct usba_request *req, *tmp_req;
+
+	list_for_each_entry_safe(req, tmp_req, list, queue) {
+		list_del_init(&req->queue);
+		request_complete(ep, req, status);
+	}
+}
+
+static int
+usba_ep_enable(struct usb_ep *_ep, const struct usb_endpoint_descriptor *desc)
+{
+	struct usba_ep *ep = to_usba_ep(_ep);
+	struct usba_udc *udc = ep->udc;
+	unsigned long flags, ept_cfg, maxpacket;
+	unsigned int nr_trans;
+
+	DBG(DBG_GADGET, "%s: ep_enable: desc=%p\n", ep->ep.name, desc);
+
+	maxpacket = usb_endpoint_maxp(desc) & 0x7ff;
+
+	if (((desc->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK)
+	      != ep->index) ||
+	      ep->index == 0 ||
+	      desc->bDescriptorType != USB_DT_ENDPOINT ||
+	      maxpacket == 0 ||
+	      maxpacket > ep->fifo_size) {
+		DBG(DBG_ERR, "ep_enable: Invalid argument");
+		return -EINVAL;
+	}
+
+	ep->is_isoc = 0;
+	ep->is_in = 0;
+
+	if (maxpacket <= 8)
+		ept_cfg = USBA_BF(EPT_SIZE, USBA_EPT_SIZE_8);
+	else
+		/* LSB is bit 1, not 0 */
+		ept_cfg = USBA_BF(EPT_SIZE, fls(maxpacket - 1) - 3);
+
+	DBG(DBG_HW, "%s: EPT_SIZE = %lu (maxpacket = %lu)\n",
+	    ep->ep.name, ept_cfg, maxpacket);
+
+	if (usb_endpoint_dir_in(desc)) {
+		ep->is_in = 1;
+		ept_cfg |= USBA_EPT_DIR_IN;
+	}
+
+	switch (usb_endpoint_type(desc)) {
+	case USB_ENDPOINT_XFER_CONTROL:
+		ept_cfg |= USBA_BF(EPT_TYPE, USBA_EPT_TYPE_CONTROL);
+		ept_cfg |= USBA_BF(BK_NUMBER, USBA_BK_NUMBER_ONE);
+		break;
+	case USB_ENDPOINT_XFER_ISOC:
+		if (!ep->can_isoc) {
+			DBG(DBG_ERR, "ep_enable: %s is not isoc capable\n",
+			    ep->ep.name);
+			return -EINVAL;
+		}
+
+		/*
+		 * Bits 11:12 specify number of _additional_
+		 * transactions per microframe.
+		 */
+		nr_trans = ((usb_endpoint_maxp(desc) >> 11) & 3) + 1;
+		if (nr_trans > 3)
+			return -EINVAL;
+
+		ep->is_isoc = 1;
+		ept_cfg |= USBA_BF(EPT_TYPE, USBA_EPT_TYPE_ISO);
+
+		/*
+		 * Do triple-buffering on high-bandwidth iso endpoints.
+		 */
+		if (nr_trans > 1 && ep->nr_banks == 3)
+			ept_cfg |= USBA_BF(BK_NUMBER, USBA_BK_NUMBER_TRIPLE);
+		else
+			ept_cfg |= USBA_BF(BK_NUMBER, USBA_BK_NUMBER_DOUBLE);
+		ept_cfg |= USBA_BF(NB_TRANS, nr_trans);
+		break;
+	case USB_ENDPOINT_XFER_BULK:
+		ept_cfg |= USBA_BF(EPT_TYPE, USBA_EPT_TYPE_BULK);
+		ept_cfg |= USBA_BF(BK_NUMBER, USBA_BK_NUMBER_ONE);
+		break;
+	case USB_ENDPOINT_XFER_INT:
+		ept_cfg |= USBA_BF(EPT_TYPE, USBA_EPT_TYPE_INT);
+		ept_cfg |= USBA_BF(BK_NUMBER, USBA_BK_NUMBER_ONE);
+		break;
+	}
+
+	spin_lock_irqsave(&ep->udc->lock, flags);
+
+	ep->desc = desc;
+	ep->ep.maxpacket = maxpacket;
+
+	usba_ep_writel(ep, CFG, ept_cfg);
+	usba_ep_writel(ep, CTL_ENB, USBA_EPT_ENABLE);
+
+	usba_writel(udc, INT_ENB,
+		    (usba_readl(udc, INT_ENB)
+		     | USBA_BF(EPT_INT, 1 << ep->index)));
+
+	spin_unlock_irqrestore(&udc->lock, flags);
+
+	DBG(DBG_HW, "EPT_CFG%d after init: %#08lx\n", ep->index,
+	    (unsigned long)usba_ep_readl(ep, CFG));
+	DBG(DBG_HW, "INT_ENB after init: %#08lx\n",
+	    (unsigned long)usba_readl(udc, INT_ENB));
+
+	return 0;
+}
+
+static int usba_ep_disable(struct usb_ep *_ep)
+{
+	struct usba_ep *ep = to_usba_ep(_ep);
+	struct usba_udc *udc = ep->udc;
+	LIST_HEAD(req_list);
+	unsigned long flags;
+
+	DBG(DBG_GADGET, "ep_disable: %s\n", ep->ep.name);
+
+	spin_lock_irqsave(&udc->lock, flags);
+
+	if (!ep->desc) {
+		spin_unlock_irqrestore(&udc->lock, flags);
+		/* REVISIT because this driver disables endpoints in
+		 * reset_all_endpoints() before calling disconnect(),
+		 * most gadget drivers would trigger this non-error ...
+		 */
+		if (udc->gadget.speed != USB_SPEED_UNKNOWN)
+			DBG(DBG_ERR, "ep_disable: %s not enabled\n",
+			    ep->ep.name);
+		return -EINVAL;
+	}
+	ep->desc = NULL;
+
+	list_splice_init(&ep->queue, &req_list);
+	usba_ep_writel(ep, CFG, 0);
+	usba_ep_writel(ep, CTL_DIS, USBA_EPT_ENABLE);
+	usba_writel(udc, INT_ENB,
+		    usba_readl(udc, INT_ENB) &
+		    ~USBA_BF(EPT_INT, 1 << ep->index));
+
+	request_complete_list(ep, &req_list, -ESHUTDOWN);
+
+	spin_unlock_irqrestore(&udc->lock, flags);
+
+	return 0;
+}
+
+static struct usb_request *
+usba_ep_alloc_request(struct usb_ep *_ep, gfp_t gfp_flags)
+{
+	struct usba_request *req;
+
+	DBG(DBG_GADGET, "ep_alloc_request: %p, 0x%x\n", _ep, gfp_flags);
+
+	req = malloc(sizeof(struct usba_request));
+	if (!req)
+		return NULL;
+
+	INIT_LIST_HEAD(&req->queue);
+
+	return &req->req;
+}
+
+static void
+usba_ep_free_request(struct usb_ep *_ep, struct usb_request *_req)
+{
+	struct usba_request *req = to_usba_req(_req);
+
+	DBG(DBG_GADGET, "ep_free_request: %p, %p\n", _ep, _req);
+
+	free(req);
+}
+
+static int
+usba_ep_queue(struct usb_ep *_ep, struct usb_request *_req, gfp_t gfp_flags)
+{
+	struct usba_request *req = to_usba_req(_req);
+	struct usba_ep *ep = to_usba_ep(_ep);
+	struct usba_udc *udc = ep->udc;
+	unsigned long flags;
+	int ret;
+
+	DBG(DBG_GADGET | DBG_QUEUE | DBG_REQ, "%s: queue req %p, len %u\n",
+	    ep->ep.name, req, _req->length);
+
+	if (!udc->driver || udc->gadget.speed == USB_SPEED_UNKNOWN ||
+	    !ep->desc)
+		return -ESHUTDOWN;
+
+	req->submitted = 0;
+	req->using_dma = 0;
+	req->last_transaction = 0;
+
+	_req->status = -EINPROGRESS;
+	_req->actual = 0;
+
+	/* May have received a reset since last time we checked */
+	ret = -ESHUTDOWN;
+	spin_lock_irqsave(&udc->lock, flags);
+	if (ep->desc) {
+		list_add_tail(&req->queue, &ep->queue);
+
+		if ((!ep_is_control(ep) && ep->is_in) ||
+		    (ep_is_control(ep) && (ep->state == DATA_STAGE_IN ||
+		    ep->state == STATUS_STAGE_IN)))
+			usba_ep_writel(ep, CTL_ENB, USBA_TX_PK_RDY);
+		else
+			usba_ep_writel(ep, CTL_ENB, USBA_RX_BK_RDY);
+
+		ret = 0;
+	}
+	spin_unlock_irqrestore(&udc->lock, flags);
+
+	return ret;
+}
+
+static int usba_ep_dequeue(struct usb_ep *_ep, struct usb_request *_req)
+{
+	struct usba_ep *ep = to_usba_ep(_ep);
+	struct usba_request *req = to_usba_req(_req);
+
+	DBG(DBG_GADGET | DBG_QUEUE, "ep_dequeue: %s, req %p\n",
+	    ep->ep.name, req);
+
+	/*
+	 * Errors should stop the queue from advancing until the
+	 * completion function returns.
+	 */
+	list_del_init(&req->queue);
+
+	request_complete(ep, req, -ECONNRESET);
+
+	/* Process the next request if any */
+	submit_next_request(ep);
+
+	return 0;
+}
+
+static int usba_ep_set_halt(struct usb_ep *_ep, int value)
+{
+	struct usba_ep *ep = to_usba_ep(_ep);
+	unsigned long flags;
+	int ret = 0;
+
+	DBG(DBG_GADGET, "endpoint %s: %s HALT\n", ep->ep.name,
+	    value ? "set" : "clear");
+
+	if (!ep->desc) {
+		DBG(DBG_ERR, "Attempted to halt uninitialized ep %s\n",
+		    ep->ep.name);
+		return -ENODEV;
+	}
+
+	if (ep->is_isoc) {
+		DBG(DBG_ERR, "Attempted to halt isochronous ep %s\n",
+		    ep->ep.name);
+		return -ENOTTY;
+	}
+
+	spin_lock_irqsave(&udc->lock, flags);
+
+	/*
+	 * We can't halt IN endpoints while there are still data to be
+	 * transferred
+	 */
+	if (!list_empty(&ep->queue) ||
+	    ((value && ep->is_in && (usba_ep_readl(ep, STA) &
+	    USBA_BF(BUSY_BANKS, -1L))))) {
+		ret = -EAGAIN;
+	} else {
+		if (value)
+			usba_ep_writel(ep, SET_STA, USBA_FORCE_STALL);
+		else
+			usba_ep_writel(ep, CLR_STA,
+				       USBA_FORCE_STALL | USBA_TOGGLE_CLR);
+		usba_ep_readl(ep, STA);
+	}
+
+	spin_unlock_irqrestore(&udc->lock, flags);
+
+	return ret;
+}
+
+static int usba_ep_fifo_status(struct usb_ep *_ep)
+{
+	struct usba_ep *ep = to_usba_ep(_ep);
+
+	return USBA_BFEXT(BYTE_COUNT, usba_ep_readl(ep, STA));
+}
+
+static void usba_ep_fifo_flush(struct usb_ep *_ep)
+{
+	struct usba_ep *ep = to_usba_ep(_ep);
+	struct usba_udc *udc = ep->udc;
+
+	usba_writel(udc, EPT_RST, 1 << ep->index);
+}
+
+static const struct usb_ep_ops usba_ep_ops = {
+	.enable		= usba_ep_enable,
+	.disable	= usba_ep_disable,
+	.alloc_request	= usba_ep_alloc_request,
+	.free_request	= usba_ep_free_request,
+	.queue		= usba_ep_queue,
+	.dequeue	= usba_ep_dequeue,
+	.set_halt	= usba_ep_set_halt,
+	.fifo_status	= usba_ep_fifo_status,
+	.fifo_flush	= usba_ep_fifo_flush,
+};
+
+static int usba_udc_get_frame(struct usb_gadget *gadget)
+{
+	struct usba_udc *udc = to_usba_udc(gadget);
+
+	return USBA_BFEXT(FRAME_NUMBER, usba_readl(udc, FNUM));
+}
+
+static int usba_udc_wakeup(struct usb_gadget *gadget)
+{
+	struct usba_udc *udc = to_usba_udc(gadget);
+	unsigned long flags;
+	u32 ctrl;
+	int ret = -EINVAL;
+
+	spin_lock_irqsave(&udc->lock, flags);
+	if (udc->devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP)) {
+		ctrl = usba_readl(udc, CTRL);
+		usba_writel(udc, CTRL, ctrl | USBA_REMOTE_WAKE_UP);
+		ret = 0;
+	}
+	spin_unlock_irqrestore(&udc->lock, flags);
+
+	return ret;
+}
+
+static int
+usba_udc_set_selfpowered(struct usb_gadget *gadget, int is_selfpowered)
+{
+	struct usba_udc *udc = to_usba_udc(gadget);
+	unsigned long flags;
+
+	spin_lock_irqsave(&udc->lock, flags);
+	if (is_selfpowered)
+		udc->devstatus |= 1 << USB_DEVICE_SELF_POWERED;
+	else
+		udc->devstatus &= ~(1 << USB_DEVICE_SELF_POWERED);
+	spin_unlock_irqrestore(&udc->lock, flags);
+
+	return 0;
+}
+
+static const struct usb_gadget_ops usba_udc_ops = {
+	.get_frame		= usba_udc_get_frame,
+	.wakeup			= usba_udc_wakeup,
+	.set_selfpowered	= usba_udc_set_selfpowered,
+};
+
+static struct usb_endpoint_descriptor usba_ep0_desc = {
+	.bLength = USB_DT_ENDPOINT_SIZE,
+	.bDescriptorType = USB_DT_ENDPOINT,
+	.bEndpointAddress = 0,
+	.bmAttributes = USB_ENDPOINT_XFER_CONTROL,
+	.wMaxPacketSize = cpu_to_le16(64),
+	/* FIXME: I have no idea what to put here */
+	.bInterval = 1,
+};
+
+/*
+ * Called with interrupts disabled and udc->lock held.
+ */
+static void reset_all_endpoints(struct usba_udc *udc)
+{
+	struct usba_ep *ep;
+	struct usba_request *req, *tmp_req;
+
+	usba_writel(udc, EPT_RST, ~0UL);
+
+	ep = to_usba_ep(udc->gadget.ep0);
+	list_for_each_entry_safe(req, tmp_req, &ep->queue, queue) {
+		list_del_init(&req->queue);
+		request_complete(ep, req, -ECONNRESET);
+	}
+
+	/* NOTE:  normally, the next call to the gadget driver is in
+	 * charge of disabling endpoints... usually disconnect().
+	 * The exception would be entering a high speed test mode.
+	 *
+	 * FIXME remove this code ... and retest thoroughly.
+	 */
+	list_for_each_entry(ep, &udc->gadget.ep_list, ep.ep_list) {
+		if (ep->desc) {
+			spin_unlock(&udc->lock);
+			usba_ep_disable(&ep->ep);
+			spin_lock(&udc->lock);
+		}
+	}
+}
+
+static struct usba_ep *get_ep_by_addr(struct usba_udc *udc, u16 wIndex)
+{
+	struct usba_ep *ep;
+
+	if ((wIndex & USB_ENDPOINT_NUMBER_MASK) == 0)
+		return to_usba_ep(udc->gadget.ep0);
+
+	list_for_each_entry(ep, &udc->gadget.ep_list, ep.ep_list) {
+		u8 bEndpointAddress;
+
+		if (!ep->desc)
+			continue;
+		bEndpointAddress = ep->desc->bEndpointAddress;
+		if ((wIndex ^ bEndpointAddress) & USB_DIR_IN)
+			continue;
+		if ((bEndpointAddress & USB_ENDPOINT_NUMBER_MASK)
+				== (wIndex & USB_ENDPOINT_NUMBER_MASK))
+			return ep;
+	}
+
+	return NULL;
+}
+
+/* Called with interrupts disabled and udc->lock held */
+static inline void set_protocol_stall(struct usba_udc *udc, struct usba_ep *ep)
+{
+	usba_ep_writel(ep, SET_STA, USBA_FORCE_STALL);
+	ep->state = WAIT_FOR_SETUP;
+}
+
+static inline int is_stalled(struct usba_udc *udc, struct usba_ep *ep)
+{
+	if (usba_ep_readl(ep, STA) & USBA_FORCE_STALL)
+		return 1;
+	return 0;
+}
+
+static inline void set_address(struct usba_udc *udc, unsigned int addr)
+{
+	u32 regval;
+
+	DBG(DBG_BUS, "setting address %u...\n", addr);
+	regval = usba_readl(udc, CTRL);
+	regval = USBA_BFINS(DEV_ADDR, addr, regval);
+	usba_writel(udc, CTRL, regval);
+}
+
+static int do_test_mode(struct usba_udc *udc)
+{
+	static const char test_packet_buffer[] = {
+		/* JKJKJKJK * 9 */
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		/* JJKKJJKK * 8 */
+		0xAA, 0xAA, 0xAA, 0xAA, 0xAA, 0xAA, 0xAA, 0xAA,
+		/* JJKKJJKK * 8 */
+		0xEE, 0xEE, 0xEE, 0xEE, 0xEE, 0xEE, 0xEE, 0xEE,
+		/* JJJJJJJKKKKKKK * 8 */
+		0xFE, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
+		0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
+		/* JJJJJJJK * 8 */
+		0x7F, 0xBF, 0xDF, 0xEF, 0xF7, 0xFB, 0xFD,
+		/* {JKKKKKKK * 10}, JK */
+		0xFC, 0x7E, 0xBF, 0xDF, 0xEF, 0xF7, 0xFB, 0xFD, 0x7E
+	};
+	struct usba_ep *ep;
+	int test_mode;
+
+	test_mode = udc->test_mode;
+
+	/* Start from a clean slate */
+	reset_all_endpoints(udc);
+
+	switch (test_mode) {
+	case 0x0100:
+		/* Test_J */
+		usba_writel(udc, TST, USBA_TST_J_MODE);
+		DBG(DBG_ALL, "Entering Test_J mode...\n");
+		break;
+	case 0x0200:
+		/* Test_K */
+		usba_writel(udc, TST, USBA_TST_K_MODE);
+		DBG(DBG_ALL, "Entering Test_K mode...\n");
+		break;
+	case 0x0300:
+		/*
+		 * Test_SE0_NAK: Force high-speed mode and set up ep0
+		 * for Bulk IN transfers
+		 */
+		ep = &udc->usba_ep[0];
+		usba_writel(udc, TST,
+			    USBA_BF(SPEED_CFG, USBA_SPEED_CFG_FORCE_HIGH));
+		usba_ep_writel(ep, CFG,
+			       USBA_BF(EPT_SIZE, USBA_EPT_SIZE_64)
+			       | USBA_EPT_DIR_IN
+			       | USBA_BF(EPT_TYPE, USBA_EPT_TYPE_BULK)
+			       | USBA_BF(BK_NUMBER, 1));
+		if (!(usba_ep_readl(ep, CFG) & USBA_EPT_MAPPED)) {
+			set_protocol_stall(udc, ep);
+			DBG(DBG_ALL, "Test_SE0_NAK: ep0 not mapped\n");
+		} else {
+			usba_ep_writel(ep, CTL_ENB, USBA_EPT_ENABLE);
+			DBG(DBG_ALL, "Entering Test_SE0_NAK mode...\n");
+		}
+		break;
+	case 0x0400:
+		/* Test_Packet */
+		ep = &udc->usba_ep[0];
+		usba_ep_writel(ep, CFG,
+			       USBA_BF(EPT_SIZE, USBA_EPT_SIZE_64)
+			       | USBA_EPT_DIR_IN
+			       | USBA_BF(EPT_TYPE, USBA_EPT_TYPE_BULK)
+			       | USBA_BF(BK_NUMBER, 1));
+		if (!(usba_ep_readl(ep, CFG) & USBA_EPT_MAPPED)) {
+			set_protocol_stall(udc, ep);
+			DBG(DBG_ALL, "Test_Packet: ep0 not mapped\n");
+		} else {
+			usba_ep_writel(ep, CTL_ENB, USBA_EPT_ENABLE);
+			usba_writel(udc, TST, USBA_TST_PKT_MODE);
+			memcpy(ep->fifo, test_packet_buffer,
+			       sizeof(test_packet_buffer));
+			usba_ep_writel(ep, SET_STA, USBA_TX_PK_RDY);
+			DBG(DBG_ALL, "Entering Test_Packet mode...\n");
+		}
+		break;
+	default:
+		DBG(DBG_ERR, "Invalid test mode: 0x%04x\n", test_mode);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+/* Avoid overly long expressions */
+static inline bool feature_is_dev_remote_wakeup(struct usb_ctrlrequest *crq)
+{
+	if (crq->wValue == cpu_to_le16(USB_DEVICE_REMOTE_WAKEUP))
+		return true;
+	return false;
+}
+
+static inline bool feature_is_dev_test_mode(struct usb_ctrlrequest *crq)
+{
+	if (crq->wValue == cpu_to_le16(USB_DEVICE_TEST_MODE))
+		return true;
+	return false;
+}
+
+static inline bool feature_is_ep_halt(struct usb_ctrlrequest *crq)
+{
+	if (crq->wValue == cpu_to_le16(USB_ENDPOINT_HALT))
+		return true;
+	return false;
+}
+
+static int handle_ep0_setup(struct usba_udc *udc, struct usba_ep *ep,
+		struct usb_ctrlrequest *crq)
+{
+	int retval = 0;
+
+	switch (crq->bRequest) {
+	case USB_REQ_GET_STATUS: {
+		u16 status;
+
+		if (crq->bRequestType == (USB_DIR_IN | USB_RECIP_DEVICE)) {
+			status = cpu_to_le16(udc->devstatus);
+		} else if (crq->bRequestType
+				== (USB_DIR_IN | USB_RECIP_INTERFACE)) {
+			status = cpu_to_le16(0);
+		} else if (crq->bRequestType
+				== (USB_DIR_IN | USB_RECIP_ENDPOINT)) {
+			struct usba_ep *target;
+
+			target = get_ep_by_addr(udc, le16_to_cpu(crq->wIndex));
+			if (!target)
+				goto stall;
+
+			status = 0;
+			if (is_stalled(udc, target))
+				status |= cpu_to_le16(1);
+		} else {
+			goto delegate;
+		}
+
+		/* Write directly to the FIFO. No queueing is done. */
+		if (crq->wLength != cpu_to_le16(sizeof(status)))
+			goto stall;
+		ep->state = DATA_STAGE_IN;
+		__raw_writew(status, ep->fifo);
+		usba_ep_writel(ep, SET_STA, USBA_TX_PK_RDY);
+		break;
+	}
+
+	case USB_REQ_CLEAR_FEATURE: {
+		if (crq->bRequestType == USB_RECIP_DEVICE) {
+			if (feature_is_dev_remote_wakeup(crq))
+				udc->devstatus
+					&= ~(1 << USB_DEVICE_REMOTE_WAKEUP);
+			else
+				/* Can't CLEAR_FEATURE TEST_MODE */
+				goto stall;
+		} else if (crq->bRequestType == USB_RECIP_ENDPOINT) {
+			struct usba_ep *target;
+
+			if (crq->wLength != cpu_to_le16(0) ||
+			    !feature_is_ep_halt(crq))
+				goto stall;
+			target = get_ep_by_addr(udc, le16_to_cpu(crq->wIndex));
+			if (!target)
+				goto stall;
+
+			usba_ep_writel(target, CLR_STA, USBA_FORCE_STALL);
+			if (target->index != 0)
+				usba_ep_writel(target, CLR_STA,
+					       USBA_TOGGLE_CLR);
+		} else {
+			goto delegate;
+		}
+
+		send_status(udc, ep);
+		break;
+	}
+
+	case USB_REQ_SET_FEATURE: {
+		if (crq->bRequestType == USB_RECIP_DEVICE) {
+			if (feature_is_dev_test_mode(crq)) {
+				send_status(udc, ep);
+				ep->state = STATUS_STAGE_TEST;
+				udc->test_mode = le16_to_cpu(crq->wIndex);
+				return 0;
+			} else if (feature_is_dev_remote_wakeup(crq)) {
+				udc->devstatus |= 1 << USB_DEVICE_REMOTE_WAKEUP;
+			} else {
+				goto stall;
+			}
+		} else if (crq->bRequestType == USB_RECIP_ENDPOINT) {
+			struct usba_ep *target;
+
+			if (crq->wLength != cpu_to_le16(0) ||
+			    !feature_is_ep_halt(crq))
+				goto stall;
+
+			target = get_ep_by_addr(udc, le16_to_cpu(crq->wIndex));
+			if (!target)
+				goto stall;
+
+			usba_ep_writel(target, SET_STA, USBA_FORCE_STALL);
+		} else {
+			goto delegate;
+		}
+
+		send_status(udc, ep);
+		break;
+	}
+
+	case USB_REQ_SET_ADDRESS:
+		if (crq->bRequestType != (USB_DIR_OUT | USB_RECIP_DEVICE))
+			goto delegate;
+
+		set_address(udc, le16_to_cpu(crq->wValue));
+		send_status(udc, ep);
+		ep->state = STATUS_STAGE_ADDR;
+		break;
+
+	default:
+delegate:
+		spin_unlock(&udc->lock);
+		retval = udc->driver->setup(&udc->gadget, crq);
+		spin_lock(&udc->lock);
+	}
+
+	return retval;
+
+stall:
+	DBG(DBG_ALL, "%s: Invalid setup request: %02x.%02x v%04x i%04x l%d\n",
+	    ep->ep.name, crq->bRequestType, crq->bRequest,
+	    le16_to_cpu(crq->wValue), le16_to_cpu(crq->wIndex),
+	    le16_to_cpu(crq->wLength));
+	set_protocol_stall(udc, ep);
+
+	return -1;
+}
+
+static void usba_control_irq(struct usba_udc *udc, struct usba_ep *ep)
+{
+	struct usba_request *req;
+	u32 epstatus;
+	u32 epctrl;
+
+restart:
+	epstatus = usba_ep_readl(ep, STA);
+	epctrl = usba_ep_readl(ep, CTL);
+
+	DBG(DBG_INT, "%s [%d]: s/%08x c/%08x\n",
+	    ep->ep.name, ep->state, epstatus, epctrl);
+
+	req = NULL;
+	if (!list_empty(&ep->queue))
+		req = list_entry(ep->queue.next,
+				 struct usba_request, queue);
+
+	if ((epctrl & USBA_TX_PK_RDY) && !(epstatus & USBA_TX_PK_RDY)) {
+		if (req->submitted)
+			next_fifo_transaction(ep, req);
+		else
+			submit_request(ep, req);
+
+		if (req->last_transaction) {
+			usba_ep_writel(ep, CTL_DIS, USBA_TX_PK_RDY);
+			usba_ep_writel(ep, CTL_ENB, USBA_TX_COMPLETE);
+		}
+		goto restart;
+	}
+	if ((epstatus & epctrl) & USBA_TX_COMPLETE) {
+		usba_ep_writel(ep, CLR_STA, USBA_TX_COMPLETE);
+
+		switch (ep->state) {
+		case DATA_STAGE_IN:
+			usba_ep_writel(ep, CTL_ENB, USBA_RX_BK_RDY);
+			usba_ep_writel(ep, CTL_DIS, USBA_TX_COMPLETE);
+			ep->state = STATUS_STAGE_OUT;
+			break;
+		case STATUS_STAGE_ADDR:
+			/* Activate our new address */
+			usba_writel(udc, CTRL, (usba_readl(udc, CTRL)
+						| USBA_FADDR_EN));
+			usba_ep_writel(ep, CTL_DIS, USBA_TX_COMPLETE);
+			ep->state = WAIT_FOR_SETUP;
+			break;
+		case STATUS_STAGE_IN:
+			if (req) {
+				list_del_init(&req->queue);
+				request_complete(ep, req, 0);
+				submit_next_request(ep);
+			}
+			usba_ep_writel(ep, CTL_DIS, USBA_TX_COMPLETE);
+			ep->state = WAIT_FOR_SETUP;
+			break;
+		case STATUS_STAGE_TEST:
+			usba_ep_writel(ep, CTL_DIS, USBA_TX_COMPLETE);
+			ep->state = WAIT_FOR_SETUP;
+			if (do_test_mode(udc))
+				set_protocol_stall(udc, ep);
+			break;
+		default:
+			DBG(DBG_ALL, "%s: TXCOMP: Invalid endpoint state %d\n",
+			    ep->ep.name, ep->state);
+			set_protocol_stall(udc, ep);
+			break;
+		}
+
+		goto restart;
+	}
+	if ((epstatus & epctrl) & USBA_RX_BK_RDY) {
+		switch (ep->state) {
+		case STATUS_STAGE_OUT:
+			usba_ep_writel(ep, CLR_STA, USBA_RX_BK_RDY);
+			usba_ep_writel(ep, CTL_DIS, USBA_RX_BK_RDY);
+
+			if (req) {
+				list_del_init(&req->queue);
+				request_complete(ep, req, 0);
+			}
+			ep->state = WAIT_FOR_SETUP;
+			break;
+
+		case DATA_STAGE_OUT:
+			receive_data(ep);
+			break;
+
+		default:
+			usba_ep_writel(ep, CLR_STA, USBA_RX_BK_RDY);
+			usba_ep_writel(ep, CTL_DIS, USBA_RX_BK_RDY);
+			DBG(DBG_ALL, "%s: RXRDY: Invalid endpoint state %d\n",
+			    ep->ep.name, ep->state);
+			set_protocol_stall(udc, ep);
+			break;
+		}
+
+		goto restart;
+	}
+	if (epstatus & USBA_RX_SETUP) {
+		union {
+			struct usb_ctrlrequest crq;
+			unsigned long data[2];
+		} crq;
+		unsigned int pkt_len;
+		int ret;
+
+		if (ep->state != WAIT_FOR_SETUP) {
+			/*
+			 * Didn't expect a SETUP packet at this
+			 * point. Clean up any pending requests (which
+			 * may be successful).
+			 */
+			int status = -EPROTO;
+
+			/*
+			 * RXRDY and TXCOMP are dropped when SETUP
+			 * packets arrive.  Just pretend we received
+			 * the status packet.
+			 */
+			if (ep->state == STATUS_STAGE_OUT ||
+			    ep->state == STATUS_STAGE_IN) {
+				usba_ep_writel(ep, CTL_DIS, USBA_RX_BK_RDY);
+				status = 0;
+			}
+
+			if (req) {
+				list_del_init(&req->queue);
+				request_complete(ep, req, status);
+			}
+		}
+
+		pkt_len = USBA_BFEXT(BYTE_COUNT, usba_ep_readl(ep, STA));
+		DBG(DBG_HW, "Packet length: %u\n", pkt_len);
+		if (pkt_len != sizeof(crq)) {
+			DBG(DBG_ALL, "udc: Invalid length %u (expected %zu)\n",
+			    pkt_len, sizeof(crq));
+			set_protocol_stall(udc, ep);
+			return;
+		}
+
+		DBG(DBG_FIFO, "Copying ctrl request from 0x%p:\n", ep->fifo);
+		memcpy(crq.data, ep->fifo, sizeof(crq));
+
+		/* Free up one bank in the FIFO so that we can
+		 * generate or receive a reply right away. */
+		usba_ep_writel(ep, CLR_STA, USBA_RX_SETUP);
+
+		if (crq.crq.bRequestType & USB_DIR_IN) {
+			/*
+			 * The USB 2.0 spec states that "if wLength is
+			 * zero, there is no data transfer phase."
+			 * However, testusb #14 seems to actually
+			 * expect a data phase even if wLength = 0...
+			 */
+			ep->state = DATA_STAGE_IN;
+		} else {
+			if (crq.crq.wLength != cpu_to_le16(0))
+				ep->state = DATA_STAGE_OUT;
+			else
+				ep->state = STATUS_STAGE_IN;
+		}
+
+		ret = -1;
+		if (ep->index == 0) {
+			ret = handle_ep0_setup(udc, ep, &crq.crq);
+		} else {
+			spin_unlock(&udc->lock);
+			ret = udc->driver->setup(&udc->gadget, &crq.crq);
+			spin_lock(&udc->lock);
+		}
+
+		DBG(DBG_BUS, "req %02x.%02x, length %d, state %d, ret %d\n",
+		    crq.crq.bRequestType, crq.crq.bRequest,
+		    le16_to_cpu(crq.crq.wLength), ep->state, ret);
+
+		if (ret < 0) {
+			/* Let the host know that we failed */
+			set_protocol_stall(udc, ep);
+		}
+	}
+}
+
+static void usba_ep_irq(struct usba_udc *udc, struct usba_ep *ep)
+{
+	struct usba_request *req;
+	u32 epstatus;
+	u32 epctrl;
+
+	epstatus = usba_ep_readl(ep, STA);
+	epctrl = usba_ep_readl(ep, CTL);
+
+	DBG(DBG_INT, "%s: interrupt, status: 0x%08x\n", ep->ep.name, epstatus);
+
+	while ((epctrl & USBA_TX_PK_RDY) && !(epstatus & USBA_TX_PK_RDY)) {
+		DBG(DBG_BUS, "%s: TX PK ready\n", ep->ep.name);
+
+		if (list_empty(&ep->queue)) {
+			DBG(DBG_INT, "ep_irq: queue empty\n");
+			usba_ep_writel(ep, CTL_DIS, USBA_TX_PK_RDY);
+			return;
+		}
+
+		req = list_entry(ep->queue.next, struct usba_request, queue);
+
+		if (req->submitted)
+			next_fifo_transaction(ep, req);
+		else
+			submit_request(ep, req);
+
+		if (req->last_transaction) {
+			list_del_init(&req->queue);
+			submit_next_request(ep);
+			request_complete(ep, req, 0);
+		}
+
+		epstatus = usba_ep_readl(ep, STA);
+		epctrl = usba_ep_readl(ep, CTL);
+	}
+
+	if ((epstatus & epctrl) & USBA_RX_BK_RDY) {
+		DBG(DBG_BUS, "%s: RX data ready\n", ep->ep.name);
+		receive_data(ep);
+		usba_ep_writel(ep, CLR_STA, USBA_RX_BK_RDY);
+	}
+}
+
+static int usba_udc_irq(struct usba_udc *udc)
+{
+	u32 status, ep_status;
+
+	spin_lock(&udc->lock);
+
+	status = usba_readl(udc, INT_STA);
+	DBG(DBG_INT, "irq, status=%#08x\n", status);
+
+	if (status & USBA_DET_SUSPEND) {
+		usba_writel(udc, INT_CLR, USBA_DET_SUSPEND);
+		DBG(DBG_BUS, "Suspend detected\n");
+		if (udc->gadget.speed != USB_SPEED_UNKNOWN &&
+		    udc->driver && udc->driver->suspend) {
+			spin_unlock(&udc->lock);
+			udc->driver->suspend(&udc->gadget);
+			spin_lock(&udc->lock);
+		}
+	}
+
+	if (status & USBA_WAKE_UP) {
+		usba_writel(udc, INT_CLR, USBA_WAKE_UP);
+		DBG(DBG_BUS, "Wake Up CPU detected\n");
+	}
+
+	if (status & USBA_END_OF_RESUME) {
+		usba_writel(udc, INT_CLR, USBA_END_OF_RESUME);
+		DBG(DBG_BUS, "Resume detected\n");
+		if (udc->gadget.speed != USB_SPEED_UNKNOWN &&
+		    udc->driver && udc->driver->resume) {
+			spin_unlock(&udc->lock);
+			udc->driver->resume(&udc->gadget);
+			spin_lock(&udc->lock);
+		}
+	}
+
+	ep_status = USBA_BFEXT(EPT_INT, status);
+	if (ep_status) {
+		int i;
+
+		for (i = 0; i < USBA_NR_ENDPOINTS; i++)
+			if (ep_status & (1 << i)) {
+				if (ep_is_control(&udc->usba_ep[i]))
+					usba_control_irq(udc, &udc->usba_ep[i]);
+				else
+					usba_ep_irq(udc, &udc->usba_ep[i]);
+			}
+	}
+
+	if (status & USBA_END_OF_RESET) {
+		struct usba_ep *ep0;
+
+		usba_writel(udc, INT_CLR, USBA_END_OF_RESET);
+		reset_all_endpoints(udc);
+
+		if (udc->gadget.speed != USB_SPEED_UNKNOWN &&
+		    udc->driver->disconnect) {
+			udc->gadget.speed = USB_SPEED_UNKNOWN;
+			spin_unlock(&udc->lock);
+			udc->driver->disconnect(&udc->gadget);
+			spin_lock(&udc->lock);
+		}
+
+		if (status & USBA_HIGH_SPEED)
+			udc->gadget.speed = USB_SPEED_HIGH;
+		else
+			udc->gadget.speed = USB_SPEED_FULL;
+
+		ep0 = &udc->usba_ep[0];
+		ep0->desc = &usba_ep0_desc;
+		ep0->state = WAIT_FOR_SETUP;
+		usba_ep_writel(ep0, CFG,
+			       (USBA_BF(EPT_SIZE, EP0_EPT_SIZE)
+				| USBA_BF(EPT_TYPE, USBA_EPT_TYPE_CONTROL)
+				| USBA_BF(BK_NUMBER, USBA_BK_NUMBER_ONE)));
+		usba_ep_writel(ep0, CTL_ENB,
+			       USBA_EPT_ENABLE | USBA_RX_SETUP);
+		usba_writel(udc, INT_ENB,
+			    (usba_readl(udc, INT_ENB)
+			     | USBA_BF(EPT_INT, 1)
+			     | USBA_DET_SUSPEND
+			     | USBA_END_OF_RESUME));
+
+		/*
+		 * Unclear why we hit this irregularly, e.g. in usbtest,
+		 * but it's clearly harmless...
+		 */
+		if (!(usba_ep_readl(ep0, CFG) & USBA_EPT_MAPPED))
+			DBG(DBG_ALL, "ODD: EP0 configuration is invalid!\n");
+	}
+
+	spin_unlock(&udc->lock);
+
+	return 0;
+}
+
+static int atmel_usba_start(struct usba_udc *udc)
+{
+	udc->devstatus = 1 << USB_DEVICE_SELF_POWERED;
+
+	udc->vbus_prev = 0;
+
+	/* If Vbus is present, enable the controller and wait for reset */
+	if (vbus_is_present(udc) && udc->vbus_prev == 0) {
+		usba_writel(udc, CTRL, USBA_ENABLE_MASK);
+		usba_writel(udc, INT_ENB, USBA_END_OF_RESET);
+	}
+
+	return 0;
+}
+
+static int atmel_usba_stop(struct usba_udc *udc)
+{
+	udc->gadget.speed = USB_SPEED_UNKNOWN;
+	reset_all_endpoints(udc);
+
+	/* This will also disable the DP pullup */
+	usba_writel(udc, CTRL, USBA_DISABLE_MASK);
+
+	return 0;
+}
+
+static struct usba_udc controller = {
+	.regs = (unsigned *)ATMEL_BASE_UDPHS,
+	.fifo = (unsigned *)ATMEL_BASE_UDPHS_FIFO,
+	.gadget = {
+		.ops		= &usba_udc_ops,
+		.ep_list	= LIST_HEAD_INIT(controller.gadget.ep_list),
+		.speed		= USB_SPEED_HIGH,
+		.is_dualspeed	= 1,
+		.name		= "atmel_usba_udc",
+	},
+};
+
+int usb_gadget_handle_interrupts(void)
+{
+	struct usba_udc *udc = &controller;
+
+	return usba_udc_irq(udc);
+}
+
+
+int usb_gadget_register_driver(struct usb_gadget_driver *driver)
+{
+	struct usba_udc *udc = &controller;
+	int ret;
+
+	if (!driver || !driver->bind || !driver->setup) {
+		printf("bad paramter\n");
+		return -EINVAL;
+	}
+
+	if (udc->driver) {
+		printf("UDC already has a gadget driver\n");
+		return -EBUSY;
+	}
+
+	atmel_usba_start(udc);
+
+	udc->driver = driver;
+
+	ret = driver->bind(&udc->gadget);
+	if (ret) {
+		error("driver->bind() returned %d\n", ret);
+		udc->driver = NULL;
+	}
+
+	return ret;
+}
+
+int usb_gadget_unregister_driver(struct usb_gadget_driver *driver)
+{
+	struct usba_udc *udc = &controller;
+
+	if (!driver || !driver->bind || !driver->setup) {
+		error("bad paramter\n");
+		return -EINVAL;
+	}
+
+	driver->unbind(&udc->gadget);
+	udc->driver = NULL;
+
+	atmel_usba_stop(udc);
+
+	return 0;
+}
+
+static struct usba_ep *usba_udc_pdata(struct usba_platform_data *pdata,
+				      struct usba_udc *udc)
+{
+	struct usba_ep *eps;
+	int i;
+
+	eps = malloc(sizeof(struct usba_ep) * pdata->num_ep);
+	if (!eps) {
+		error("failed to alloc eps\n");
+		return NULL;
+	}
+
+	udc->gadget.ep0 = &eps[0].ep;
+
+	INIT_LIST_HEAD(&udc->gadget.ep_list);
+	INIT_LIST_HEAD(&eps[0].ep.ep_list);
+
+	for (i = 0; i < pdata->num_ep; i++) {
+		struct usba_ep *ep = &eps[i];
+
+		ep->ep_regs = udc->regs + USBA_EPT_BASE(i);
+		ep->dma_regs = udc->regs + USBA_DMA_BASE(i);
+		ep->fifo = udc->fifo + USBA_FIFO_BASE(i);
+		ep->ep.ops = &usba_ep_ops;
+		ep->ep.name = pdata->ep[i].name;
+		ep->ep.maxpacket = pdata->ep[i].fifo_size;
+		ep->fifo_size = ep->ep.maxpacket;
+		ep->udc = udc;
+		INIT_LIST_HEAD(&ep->queue);
+		ep->nr_banks = pdata->ep[i].nr_banks;
+		ep->index = pdata->ep[i].index;
+		ep->can_dma = pdata->ep[i].can_dma;
+		ep->can_isoc = pdata->ep[i].can_isoc;
+		if (i)
+			list_add_tail(&ep->ep.ep_list, &udc->gadget.ep_list);
+	};
+
+	return eps;
+}
+
+int usba_udc_probe(struct usba_platform_data *pdata)
+{
+	struct usba_udc *udc;
+
+	udc = &controller;
+
+	udc->usba_ep = usba_udc_pdata(pdata, udc);
+
+	return 0;
+}
diff --git a/drivers/usb/gadget/atmel_usba_udc.h b/drivers/usb/gadget/atmel_usba_udc.h
new file mode 100644
index 0000000..92e462d
--- /dev/null
+++ b/drivers/usb/gadget/atmel_usba_udc.h
@@ -0,0 +1,326 @@
+/*
+ * Register definition for Atmel USBA high speed USB device controller
+ * [Original from Linux kernel: drivers/usb/gadget/atmel_usba_udc.h]
+ *
+ * Copyright (C) 2005-2013 Atmel Corporation
+ *			   Bo Shen <voice.shen@atmel.com>
+ *
+ * SPDX-License-Identifier:     GPL-2.0+
+ */
+
+#ifndef __LINUX_USB_GADGET_USBA_UDC_H__
+#define __LINUX_USB_GADGET_USBA_UDC_H__
+
+/* USB register offsets */
+#define USBA_CTRL				0x0000
+#define USBA_FNUM				0x0004
+#define USBA_INT_ENB				0x0010
+#define USBA_INT_STA				0x0014
+#define USBA_INT_CLR				0x0018
+#define USBA_EPT_RST				0x001c
+#define USBA_TST				0x00e0
+
+/* USB endpoint register offsets */
+#define USBA_EPT_CFG				0x0000
+#define USBA_EPT_CTL_ENB			0x0004
+#define USBA_EPT_CTL_DIS			0x0008
+#define USBA_EPT_CTL				0x000c
+#define USBA_EPT_SET_STA			0x0014
+#define USBA_EPT_CLR_STA			0x0018
+#define USBA_EPT_STA				0x001c
+
+/* USB DMA register offsets */
+#define USBA_DMA_NXT_DSC			0x0000
+#define USBA_DMA_ADDRESS			0x0004
+#define USBA_DMA_CONTROL			0x0008
+#define USBA_DMA_STATUS				0x000c
+
+/* Bitfields in CTRL */
+#define USBA_DEV_ADDR_OFFSET			0
+#define USBA_DEV_ADDR_SIZE			7
+#define USBA_FADDR_EN				(1 <<  7)
+#define USBA_EN_USBA				(1 <<  8)
+#define USBA_DETACH				(1 <<  9)
+#define USBA_REMOTE_WAKE_UP			(1 << 10)
+#define USBA_PULLD_DIS				(1 << 11)
+
+#if defined(CONFIG_AVR32)
+#define USBA_ENABLE_MASK			USBA_EN_USBA
+#define USBA_DISABLE_MASK			0
+#elif defined(CONFIG_AT91FAMILY)
+#define USBA_ENABLE_MASK			(USBA_EN_USBA | USBA_PULLD_DIS)
+#define USBA_DISABLE_MASK			USBA_DETACH
+#endif /* CONFIG_ARCH_AT91 */
+
+/* Bitfields in FNUM */
+#define USBA_MICRO_FRAME_NUM_OFFSET		0
+#define USBA_MICRO_FRAME_NUM_SIZE		3
+#define USBA_FRAME_NUMBER_OFFSET		3
+#define USBA_FRAME_NUMBER_SIZE			11
+#define USBA_FRAME_NUM_ERROR			(1 << 31)
+
+/* Bitfields in INT_ENB/INT_STA/INT_CLR */
+#define USBA_HIGH_SPEED				(1 <<  0)
+#define USBA_DET_SUSPEND			(1 <<  1)
+#define USBA_MICRO_SOF				(1 <<  2)
+#define USBA_SOF				(1 <<  3)
+#define USBA_END_OF_RESET			(1 <<  4)
+#define USBA_WAKE_UP				(1 <<  5)
+#define USBA_END_OF_RESUME			(1 <<  6)
+#define USBA_UPSTREAM_RESUME			(1 <<  7)
+#define USBA_EPT_INT_OFFSET			8
+#define USBA_EPT_INT_SIZE			16
+#define USBA_DMA_INT_OFFSET			24
+#define USBA_DMA_INT_SIZE			8
+
+/* Bitfields in EPT_RST */
+#define USBA_RST_OFFSET				0
+#define USBA_RST_SIZE				16
+
+/* Bitfields in USBA_TST */
+#define USBA_SPEED_CFG_OFFSET			0
+#define USBA_SPEED_CFG_SIZE			2
+#define USBA_TST_J_MODE				(1 <<  2)
+#define USBA_TST_K_MODE				(1 <<  3)
+#define USBA_TST_PKT_MODE			(1 <<  4)
+#define USBA_OPMODE2				(1 <<  5)
+
+/* Bitfields in EPT_CFG */
+#define USBA_EPT_SIZE_OFFSET			0
+#define USBA_EPT_SIZE_SIZE			3
+#define USBA_EPT_DIR_IN				(1 <<  3)
+#define USBA_EPT_TYPE_OFFSET			4
+#define USBA_EPT_TYPE_SIZE			2
+#define USBA_BK_NUMBER_OFFSET			6
+#define USBA_BK_NUMBER_SIZE			2
+#define USBA_NB_TRANS_OFFSET			8
+#define USBA_NB_TRANS_SIZE			2
+#define USBA_EPT_MAPPED				(1 << 31)
+
+/* Bitfields in EPT_CTL/EPT_CTL_ENB/EPT_CTL_DIS */
+#define USBA_EPT_ENABLE				(1 <<  0)
+#define USBA_AUTO_VALID				(1 <<  1)
+#define USBA_INTDIS_DMA				(1 <<  3)
+#define USBA_NYET_DIS				(1 <<  4)
+#define USBA_DATAX_RX				(1 <<  6)
+#define USBA_MDATA_RX				(1 <<  7)
+/* Bits 8-15 and 31 enable interrupts for respective bits in EPT_STA */
+#define USBA_BUSY_BANK_IE			(1 << 18)
+
+/* Bitfields in EPT_SET_STA/EPT_CLR_STA/EPT_STA */
+#define USBA_FORCE_STALL			(1 <<  5)
+#define USBA_TOGGLE_CLR				(1 <<  6)
+#define USBA_TOGGLE_SEQ_OFFSET			6
+#define USBA_TOGGLE_SEQ_SIZE			2
+#define USBA_ERR_OVFLW				(1 <<  8)
+#define USBA_RX_BK_RDY				(1 <<  9)
+#define USBA_KILL_BANK				(1 <<  9)
+#define USBA_TX_COMPLETE			(1 << 10)
+#define USBA_TX_PK_RDY				(1 << 11)
+#define USBA_ISO_ERR_TRANS			(1 << 11)
+#define USBA_RX_SETUP				(1 << 12)
+#define USBA_ISO_ERR_FLOW			(1 << 12)
+#define USBA_STALL_SENT				(1 << 13)
+#define USBA_ISO_ERR_CRC			(1 << 13)
+#define USBA_ISO_ERR_NBTRANS			(1 << 13)
+#define USBA_NAK_IN				(1 << 14)
+#define USBA_ISO_ERR_FLUSH			(1 << 14)
+#define USBA_NAK_OUT				(1 << 15)
+#define USBA_CURRENT_BANK_OFFSET		16
+#define USBA_CURRENT_BANK_SIZE			2
+#define USBA_BUSY_BANKS_OFFSET			18
+#define USBA_BUSY_BANKS_SIZE			2
+#define USBA_BYTE_COUNT_OFFSET			20
+#define USBA_BYTE_COUNT_SIZE			11
+#define USBA_SHORT_PACKET			(1 << 31)
+
+/* Bitfields in DMA_CONTROL */
+#define USBA_DMA_CH_EN				(1 <<  0)
+#define USBA_DMA_LINK				(1 <<  1)
+#define USBA_DMA_END_TR_EN			(1 <<  2)
+#define USBA_DMA_END_BUF_EN			(1 <<  3)
+#define USBA_DMA_END_TR_IE			(1 <<  4)
+#define USBA_DMA_END_BUF_IE			(1 <<  5)
+#define USBA_DMA_DESC_LOAD_IE			(1 <<  6)
+#define USBA_DMA_BURST_LOCK			(1 <<  7)
+#define USBA_DMA_BUF_LEN_OFFSET			16
+#define USBA_DMA_BUF_LEN_SIZE			16
+
+/* Bitfields in DMA_STATUS */
+#define USBA_DMA_CH_ACTIVE			(1 <<  1)
+#define USBA_DMA_END_TR_ST			(1 <<  4)
+#define USBA_DMA_END_BUF_ST			(1 <<  5)
+#define USBA_DMA_DESC_LOAD_ST			(1 <<  6)
+
+/* Constants for SPEED_CFG */
+#define USBA_SPEED_CFG_NORMAL			0
+#define USBA_SPEED_CFG_FORCE_HIGH		2
+#define USBA_SPEED_CFG_FORCE_FULL		3
+
+/* Constants for EPT_SIZE */
+#define USBA_EPT_SIZE_8				0
+#define USBA_EPT_SIZE_16			1
+#define USBA_EPT_SIZE_32			2
+#define USBA_EPT_SIZE_64			3
+#define USBA_EPT_SIZE_128			4
+#define USBA_EPT_SIZE_256			5
+#define USBA_EPT_SIZE_512			6
+#define USBA_EPT_SIZE_1024			7
+
+/* Constants for EPT_TYPE */
+#define USBA_EPT_TYPE_CONTROL			0
+#define USBA_EPT_TYPE_ISO			1
+#define USBA_EPT_TYPE_BULK			2
+#define USBA_EPT_TYPE_INT			3
+
+/* Constants for BK_NUMBER */
+#define USBA_BK_NUMBER_ZERO			0
+#define USBA_BK_NUMBER_ONE			1
+#define USBA_BK_NUMBER_DOUBLE			2
+#define USBA_BK_NUMBER_TRIPLE			3
+
+/* Bit manipulation macros */
+#define USBA_BF(name, value)					\
+	(((value) & ((1 << USBA_##name##_SIZE) - 1))		\
+	 << USBA_##name##_OFFSET)
+#define USBA_BFEXT(name, value)					\
+	(((value) >> USBA_##name##_OFFSET)			\
+	 & ((1 << USBA_##name##_SIZE) - 1))
+#define USBA_BFINS(name, value, old)				\
+	(((old) & ~(((1 << USBA_##name##_SIZE) - 1)		\
+		    << USBA_##name##_OFFSET))			\
+	 | USBA_BF(name, value))
+
+/* Register access macros */
+#define usba_readl(udc, reg)					\
+	__raw_readl((udc)->regs + USBA_##reg)
+#define usba_writel(udc, reg, value)				\
+	__raw_writel((value), (udc)->regs + USBA_##reg)
+#define usba_ep_readl(ep, reg)					\
+	__raw_readl((ep)->ep_regs + USBA_EPT_##reg)
+#define usba_ep_writel(ep, reg, value)				\
+	__raw_writel((value), (ep)->ep_regs + USBA_EPT_##reg)
+#define usba_dma_readl(ep, reg)					\
+	__raw_readl((ep)->dma_regs + USBA_DMA_##reg)
+#define usba_dma_writel(ep, reg, value)				\
+	__raw_writel((value), (ep)->dma_regs + USBA_DMA_##reg)
+
+/* Calculate base address for a given endpoint or DMA controller */
+#define USBA_EPT_BASE(x)	(0x100 + (x) * 0x20)
+#define USBA_DMA_BASE(x)	(0x300 + (x) * 0x10)
+#define USBA_FIFO_BASE(x)	((x) << 16)
+
+/* Synth parameters */
+#define USBA_NR_ENDPOINTS	7
+
+#define EP0_FIFO_SIZE		64
+#define EP0_EPT_SIZE		USBA_EPT_SIZE_64
+#define EP0_NR_BANKS		1
+
+#define DBG_ERR		0x0001	/* report all error returns */
+#define DBG_HW		0x0002	/* debug hardware initialization */
+#define DBG_GADGET	0x0004	/* calls to/from gadget driver */
+#define DBG_INT		0x0008	/* interrupts */
+#define DBG_BUS		0x0010	/* report changes in bus state */
+#define DBG_QUEUE	0x0020  /* debug request queue processing */
+#define DBG_FIFO	0x0040  /* debug FIFO contents */
+#define DBG_DMA		0x0080  /* debug DMA handling */
+#define DBG_REQ		0x0100	/* print out queued request length */
+#define DBG_ALL		0xffff
+#define DBG_NONE	0x0000
+
+#define DEBUG_LEVEL	(DBG_ERR)
+
+#define DBG(level, fmt, ...)					\
+	do {							\
+		if ((level) & DEBUG_LEVEL)			\
+			debug("udc: " fmt, ## __VA_ARGS__);	\
+	} while (0)
+
+enum usba_ctrl_state {
+	WAIT_FOR_SETUP,
+	DATA_STAGE_IN,
+	DATA_STAGE_OUT,
+	STATUS_STAGE_IN,
+	STATUS_STAGE_OUT,
+	STATUS_STAGE_ADDR,
+	STATUS_STAGE_TEST,
+};
+
+struct usba_dma_desc {
+	dma_addr_t next;
+	dma_addr_t addr;
+	u32 ctrl;
+};
+
+struct usba_ep {
+	int					state;
+	void					*ep_regs;
+	void					*dma_regs;
+	void					*fifo;
+	struct usb_ep				ep;
+	struct usba_udc				*udc;
+
+	struct list_head			queue;
+
+	u16					fifo_size;
+	u8					nr_banks;
+	u8					index;
+	unsigned int				can_dma:1;
+	unsigned int				can_isoc:1;
+	unsigned int				is_isoc:1;
+	unsigned int				is_in:1;
+
+	const struct usb_endpoint_descriptor	*desc;
+};
+
+struct usba_request {
+	struct usb_request			req;
+	struct list_head			queue;
+
+	u32					ctrl;
+
+	unsigned int				submitted:1;
+	unsigned int				last_transaction:1;
+	unsigned int				using_dma:1;
+	unsigned int				mapped:1;
+};
+
+struct usba_udc {
+	void *regs;
+	void *fifo;
+
+	struct usb_gadget gadget;
+	struct usb_gadget_driver *driver;
+	struct platform_device *pdev;
+	int irq;
+	int vbus_pin;
+	int vbus_pin_inverted;
+	int num_ep;
+	struct usba_ep *usba_ep;
+
+	u16 devstatus;
+
+	u16 test_mode;
+	int vbus_prev;
+};
+
+static inline struct usba_ep *to_usba_ep(struct usb_ep *ep)
+{
+	return container_of(ep, struct usba_ep, ep);
+}
+
+static inline struct usba_request *to_usba_req(struct usb_request *req)
+{
+	return container_of(req, struct usba_request, req);
+}
+
+static inline struct usba_udc *to_usba_udc(struct usb_gadget *gadget)
+{
+	return container_of(gadget, struct usba_udc, gadget);
+}
+
+#define ep_is_control(ep)	((ep)->index == 0)
+#define ep_is_idle(ep)		((ep)->state == EP_STATE_IDLE)
+
+#endif /* __LINUX_USB_GADGET_USBA_UDC_H */
diff --git a/include/linux/usb/atmel_usba_udc.h b/include/linux/usb/atmel_usba_udc.h
new file mode 100644
index 0000000..be29ef0
--- /dev/null
+++ b/include/linux/usb/atmel_usba_udc.h
@@ -0,0 +1,26 @@
+/*
+ * Platform data definitions for Atmel USBA gadget driver
+ * [Original from Linux kernel: include/linux/usb/atmel_usba_udc.h]
+ *
+ * SPDX-License-Identifier:     GPL-2.0+
+ */
+#ifndef __LINUX_USB_USBA_H__
+#define __LINUX_USB_USBA_H__
+
+struct usba_ep_data {
+	char *name;
+	int index;
+	int fifo_size;
+	int nr_banks;
+	int can_dma;
+	int can_isoc;
+};
+
+struct usba_platform_data {
+	int			num_ep;
+	struct usba_ep_data	*ep;
+};
+
+extern int usba_udc_probe(struct usba_platform_data *pdata);
+
+#endif /* __LINUX_USB_USBA_H */