/*
   * Driver for the Atmel USBA high speed USB device controller
   *
   * Copyright (C) 2005-2007 Atmel Corporation
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License version 2 as
   * published by the Free Software Foundation.
   */
  #include <linux/clk.h>
  #include <linux/module.h>
  #include <linux/init.h>
  #include <linux/interrupt.h>
  #include <linux/io.h>

  #include <linux/slab.h>

  #include <linux/device.h>
  #include <linux/dma-mapping.h>
  #include <linux/list.h>
  #include <linux/platform_device.h>
  #include <linux/usb/ch9.h>
  #include <linux/usb/gadget.h>

  #include <linux/usb/atmel_usba_udc.h>

  #include <linux/delay.h>

  #include <linux/platform_data/atmel.h>

  #include <linux/of.h>
  #include <linux/of_gpio.h>

  
  #include <asm/gpio.h>

  
  #include "atmel_usba_udc.h"

  #ifdef CONFIG_USB_GADGET_DEBUG_FS
  #include <linux/debugfs.h>
  #include <linux/uaccess.h>
  
  static int queue_dbg_open(struct inode *inode, struct file *file)
  {
  	struct usba_ep *ep = inode->i_private;
  	struct usba_request *req, *req_copy;
  	struct list_head *queue_data;
  
  	queue_data = kmalloc(sizeof(*queue_data), GFP_KERNEL);
  	if (!queue_data)
  		return -ENOMEM;
  	INIT_LIST_HEAD(queue_data);
  
  	spin_lock_irq(&ep->udc->lock);
  	list_for_each_entry(req, &ep->queue, queue) {

  		req_copy = kmemdup(req, sizeof(*req_copy), GFP_ATOMIC);

  		if (!req_copy)
  			goto fail;

  		list_add_tail(&req_copy->queue, queue_data);
  	}
  	spin_unlock_irq(&ep->udc->lock);
  
  	file->private_data = queue_data;
  	return 0;
  
  fail:
  	spin_unlock_irq(&ep->udc->lock);
  	list_for_each_entry_safe(req, req_copy, queue_data, queue) {
  		list_del(&req->queue);
  		kfree(req);
  	}
  	kfree(queue_data);
  	return -ENOMEM;
  }
  
  /*
   * bbbbbbbb llllllll IZS sssss nnnn FDL
  \0
   *
   * b: buffer address
   * l: buffer length
   * I/i: interrupt/no interrupt
   * Z/z: zero/no zero
   * S/s: short ok/short not ok
   * s: status
   * n: nr_packets
   * F/f: submitted/not submitted to FIFO
   * D/d: using/not using DMA
   * L/l: last transaction/not last transaction
   */
  static ssize_t queue_dbg_read(struct file *file, char __user *buf,
  		size_t nbytes, loff_t *ppos)
  {
  	struct list_head *queue = file->private_data;
  	struct usba_request *req, *tmp_req;
  	size_t len, remaining, actual = 0;
  	char tmpbuf[38];
  
  	if (!access_ok(VERIFY_WRITE, buf, nbytes))
  		return -EFAULT;

  	mutex_lock(&file_inode(file)->i_mutex);

  	list_for_each_entry_safe(req, tmp_req, queue, queue) {
  		len = snprintf(tmpbuf, sizeof(tmpbuf),
  				"%8p %08x %c%c%c %5d %c%c%c
  ",
  				req->req.buf, req->req.length,
  				req->req.no_interrupt ? 'i' : 'I',
  				req->req.zero ? 'Z' : 'z',
  				req->req.short_not_ok ? 's' : 'S',
  				req->req.status,
  				req->submitted ? 'F' : 'f',
  				req->using_dma ? 'D' : 'd',
  				req->last_transaction ? 'L' : 'l');
  		len = min(len, sizeof(tmpbuf));
  		if (len > nbytes)
  			break;
  
  		list_del(&req->queue);
  		kfree(req);
  
  		remaining = __copy_to_user(buf, tmpbuf, len);
  		actual += len - remaining;
  		if (remaining)
  			break;
  
  		nbytes -= len;
  		buf += len;
  	}

  	mutex_unlock(&file_inode(file)->i_mutex);

  
  	return actual;
  }
  
  static int queue_dbg_release(struct inode *inode, struct file *file)
  {
  	struct list_head *queue_data = file->private_data;
  	struct usba_request *req, *tmp_req;
  
  	list_for_each_entry_safe(req, tmp_req, queue_data, queue) {
  		list_del(&req->queue);
  		kfree(req);
  	}
  	kfree(queue_data);
  	return 0;
  }
  
  static int regs_dbg_open(struct inode *inode, struct file *file)
  {
  	struct usba_udc *udc;
  	unsigned int i;
  	u32 *data;
  	int ret = -ENOMEM;
  
  	mutex_lock(&inode->i_mutex);
  	udc = inode->i_private;
  	data = kmalloc(inode->i_size, GFP_KERNEL);
  	if (!data)
  		goto out;
  
  	spin_lock_irq(&udc->lock);
  	for (i = 0; i < inode->i_size / 4; i++)
  		data[i] = __raw_readl(udc->regs + i * 4);
  	spin_unlock_irq(&udc->lock);
  
  	file->private_data = data;
  	ret = 0;
  
  out:
  	mutex_unlock(&inode->i_mutex);
  
  	return ret;
  }
  
  static ssize_t regs_dbg_read(struct file *file, char __user *buf,
  		size_t nbytes, loff_t *ppos)
  {

  	struct inode *inode = file_inode(file);

  	int ret;
  
  	mutex_lock(&inode->i_mutex);
  	ret = simple_read_from_buffer(buf, nbytes, ppos,
  			file->private_data,

  			file_inode(file)->i_size);

  	mutex_unlock(&inode->i_mutex);
  
  	return ret;
  }
  
  static int regs_dbg_release(struct inode *inode, struct file *file)
  {
  	kfree(file->private_data);
  	return 0;
  }
  
  const struct file_operations queue_dbg_fops = {
  	.owner		= THIS_MODULE,
  	.open		= queue_dbg_open,
  	.llseek		= no_llseek,
  	.read		= queue_dbg_read,
  	.release	= queue_dbg_release,
  };
  
  const struct file_operations regs_dbg_fops = {
  	.owner		= THIS_MODULE,
  	.open		= regs_dbg_open,
  	.llseek		= generic_file_llseek,
  	.read		= regs_dbg_read,
  	.release	= regs_dbg_release,
  };
  
  static void usba_ep_init_debugfs(struct usba_udc *udc,
  		struct usba_ep *ep)
  {
  	struct dentry *ep_root;
  
  	ep_root = debugfs_create_dir(ep->ep.name, udc->debugfs_root);
  	if (!ep_root)
  		goto err_root;
  	ep->debugfs_dir = ep_root;
  
  	ep->debugfs_queue = debugfs_create_file("queue", 0400, ep_root,
  						ep, &queue_dbg_fops);
  	if (!ep->debugfs_queue)
  		goto err_queue;
  
  	if (ep->can_dma) {
  		ep->debugfs_dma_status
  			= debugfs_create_u32("dma_status", 0400, ep_root,
  					&ep->last_dma_status);
  		if (!ep->debugfs_dma_status)
  			goto err_dma_status;
  	}
  	if (ep_is_control(ep)) {
  		ep->debugfs_state
  			= debugfs_create_u32("state", 0400, ep_root,
  					&ep->state);
  		if (!ep->debugfs_state)
  			goto err_state;
  	}
  
  	return;
  
  err_state:
  	if (ep->can_dma)
  		debugfs_remove(ep->debugfs_dma_status);
  err_dma_status:
  	debugfs_remove(ep->debugfs_queue);
  err_queue:
  	debugfs_remove(ep_root);
  err_root:
  	dev_err(&ep->udc->pdev->dev,
  		"failed to create debugfs directory for %s
  ", ep->ep.name);
  }
  
  static void usba_ep_cleanup_debugfs(struct usba_ep *ep)
  {
  	debugfs_remove(ep->debugfs_queue);
  	debugfs_remove(ep->debugfs_dma_status);
  	debugfs_remove(ep->debugfs_state);
  	debugfs_remove(ep->debugfs_dir);
  	ep->debugfs_dma_status = NULL;
  	ep->debugfs_dir = NULL;
  }
  
  static void usba_init_debugfs(struct usba_udc *udc)
  {
  	struct dentry *root, *regs;
  	struct resource *regs_resource;
  
  	root = debugfs_create_dir(udc->gadget.name, NULL);
  	if (IS_ERR(root) || !root)
  		goto err_root;
  	udc->debugfs_root = root;
  
  	regs = debugfs_create_file("regs", 0400, root, udc, &regs_dbg_fops);
  	if (!regs)
  		goto err_regs;
  
  	regs_resource = platform_get_resource(udc->pdev, IORESOURCE_MEM,
  				CTRL_IOMEM_ID);

  	regs->d_inode->i_size = resource_size(regs_resource);

  	udc->debugfs_regs = regs;
  
  	usba_ep_init_debugfs(udc, to_usba_ep(udc->gadget.ep0));
  
  	return;
  
  err_regs:
  	debugfs_remove(root);
  err_root:
  	udc->debugfs_root = NULL;
  	dev_err(&udc->pdev->dev, "debugfs is not available
  ");
  }
  
  static void usba_cleanup_debugfs(struct usba_udc *udc)
  {
  	usba_ep_cleanup_debugfs(to_usba_ep(udc->gadget.ep0));
  	debugfs_remove(udc->debugfs_regs);
  	debugfs_remove(udc->debugfs_root);
  	udc->debugfs_regs = NULL;
  	udc->debugfs_root = NULL;
  }
  #else
  static inline void usba_ep_init_debugfs(struct usba_udc *udc,
  					 struct usba_ep *ep)
  {
  
  }
  
  static inline void usba_ep_cleanup_debugfs(struct usba_ep *ep)
  {
  
  }
  
  static inline void usba_init_debugfs(struct usba_udc *udc)
  {
  
  }
  
  static inline void usba_cleanup_debugfs(struct usba_udc *udc)
  {
  
  }
  #endif
  
  static int vbus_is_present(struct usba_udc *udc)
  {

  	if (gpio_is_valid(udc->vbus_pin))

  		return gpio_get_value(udc->vbus_pin) ^ udc->vbus_pin_inverted;

  
  	/* No Vbus detection: Assume always present */
  	return 1;
  }

  #if defined(CONFIG_ARCH_AT91SAM9RL)

  #include <linux/clk/at91_pmc.h>

  
  static void toggle_bias(int is_on)

  {

  	unsigned int uckr = at91_pmc_read(AT91_CKGR_UCKR);

  
  	if (is_on)

  		at91_pmc_write(AT91_CKGR_UCKR, uckr | AT91_PMC_BIASEN);

  	else

  		at91_pmc_write(AT91_CKGR_UCKR, uckr & ~(AT91_PMC_BIASEN));

  }

  #else
  
  static void toggle_bias(int is_on)
  {
  }
  
  #endif /* CONFIG_ARCH_AT91SAM9RL */

  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
  ",
  		ep->ep.name, req, transaction_len,
  		req->last_transaction ? ", done" : "");

  	memcpy_toio(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)
  ",
  		ep->ep.name, req, req->req.length);
  
  	req->req.actual = 0;
  	req->submitted = 1;
  
  	if (req->using_dma) {
  		if (req->req.length == 0) {
  			usba_ep_writel(ep, CTL_ENB, USBA_TX_PK_RDY);
  			return;
  		}
  
  		if (req->req.zero)
  			usba_ep_writel(ep, CTL_ENB, USBA_SHORT_PACKET);
  		else
  			usba_ep_writel(ep, CTL_DIS, USBA_SHORT_PACKET);
  
  		usba_dma_writel(ep, ADDRESS, req->req.dma);
  		usba_dma_writel(ep, CONTROL, req->ctrl);
  	} else {
  		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
  ", 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 & (1 << 31))
  			is_complete = 1;
  		if (req->req.actual + bytecount >= req->req.length) {
  			is_complete = 1;
  			bytecount = req->req.length - req->req.actual;
  		}

  		memcpy_fromio(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
  ", ep->ep.name);
  			req->req.status = 0;
  			list_del_init(&req->queue);
  			usba_ep_writel(ep, CTL_DIS, USBA_RX_BK_RDY);
  			spin_unlock(&udc->lock);

  			usb_gadget_giveback_request(&ep->ep, &req->req);

  			spin_lock(&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)
  {
  	struct usba_udc *udc = ep->udc;
  
  	WARN_ON(!list_empty(&req->queue));
  
  	if (req->req.status == -EINPROGRESS)
  		req->req.status = status;

  	if (req->using_dma)
  		usb_gadget_unmap_request(&udc->gadget, &req->req, ep->is_in);

  
  	DBG(DBG_GADGET | DBG_REQ,
  		"%s: req %p complete: status %d, actual %u
  ",
  		ep->ep.name, req, req->req.status, req->req.actual);
  
  	spin_unlock(&udc->lock);

  	usb_gadget_giveback_request(&ep->ep, &req->req);

  	spin_lock(&udc->lock);
  }
  
  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
  ", 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)
  ",
  			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
  ",
  					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_DOUBLE);
  		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_DOUBLE);
  		break;
  	}
  
  	spin_lock_irqsave(&ep->udc->lock, flags);

  	ep->ep.desc = desc;

  	ep->ep.maxpacket = maxpacket;
  
  	usba_ep_writel(ep, CFG, ept_cfg);
  	usba_ep_writel(ep, CTL_ENB, USBA_EPT_ENABLE);
  
  	if (ep->can_dma) {
  		u32 ctrl;
  
  		usba_writel(udc, INT_ENB,
  				(usba_readl(udc, INT_ENB)
  					| USBA_BF(EPT_INT, 1 << ep->index)
  					| USBA_BF(DMA_INT, 1 << ep->index)));
  		ctrl = USBA_AUTO_VALID | USBA_INTDIS_DMA;
  		usba_ep_writel(ep, CTL_ENB, ctrl);
  	} else {
  		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
  ", ep->index,
  			(unsigned long)usba_ep_readl(ep, CFG));
  	DBG(DBG_HW, "INT_ENB after init: %#08lx
  ",
  			(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
  ", ep->ep.name);
  
  	spin_lock_irqsave(&udc->lock, flags);

  	if (!ep->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
  ",
  					ep->ep.name);

  		return -EINVAL;
  	}

  	ep->ep.desc = NULL;

  
  	list_splice_init(&ep->queue, &req_list);
  	if (ep->can_dma) {
  		usba_dma_writel(ep, CONTROL, 0);
  		usba_dma_writel(ep, ADDRESS, 0);
  		usba_dma_readl(ep, STATUS);
  	}
  	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
  ", _ep, gfp_flags);
  
  	req = kzalloc(sizeof(*req), gfp_flags);
  	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
  ", _ep, _req);
  
  	kfree(req);
  }
  
  static int queue_dma(struct usba_udc *udc, struct usba_ep *ep,
  		struct usba_request *req, gfp_t gfp_flags)
  {
  	unsigned long flags;
  	int ret;
  
  	DBG(DBG_DMA, "%s: req l/%u d/%08x %c%c%c
  ",
  		ep->ep.name, req->req.length, req->req.dma,
  		req->req.zero ? 'Z' : 'z',
  		req->req.short_not_ok ? 'S' : 's',
  		req->req.no_interrupt ? 'I' : 'i');
  
  	if (req->req.length > 0x10000) {
  		/* Lengths from 0 to 65536 (inclusive) are supported */
  		DBG(DBG_ERR, "invalid request length %u
  ", req->req.length);
  		return -EINVAL;
  	}

  	ret = usb_gadget_map_request(&udc->gadget, &req->req, ep->is_in);
  	if (ret)
  		return ret;

  	req->using_dma = 1;

  	req->ctrl = USBA_BF(DMA_BUF_LEN, req->req.length)
  			| USBA_DMA_CH_EN | USBA_DMA_END_BUF_IE

  			| USBA_DMA_END_BUF_EN;

  	if (!ep->is_in)
  		req->ctrl |= USBA_DMA_END_TR_EN | USBA_DMA_END_TR_IE;

  
  	/*
  	 * Add this request to the queue and submit for DMA if
  	 * possible. Check if we're still alive first -- we may have
  	 * received a reset since last time we checked.
  	 */
  	ret = -ESHUTDOWN;
  	spin_lock_irqsave(&udc->lock, flags);

  	if (ep->ep.desc) {

  		if (list_empty(&ep->queue))
  			submit_request(ep, req);
  
  		list_add_tail(&req->queue, &ep->queue);
  		ret = 0;
  	}
  	spin_unlock_irqrestore(&udc->lock, flags);
  
  	return ret;
  }
  
  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
  ",
  			ep->ep.name, req, _req->length);

  	if (!udc->driver || udc->gadget.speed == USB_SPEED_UNKNOWN ||
  	    !ep->ep.desc)

  		return -ESHUTDOWN;
  
  	req->submitted = 0;
  	req->using_dma = 0;
  	req->last_transaction = 0;
  
  	_req->status = -EINPROGRESS;
  	_req->actual = 0;
  
  	if (ep->can_dma)
  		return queue_dma(udc, ep, req, gfp_flags);
  
  	/* May have received a reset since last time we checked */
  	ret = -ESHUTDOWN;
  	spin_lock_irqsave(&udc->lock, flags);

  	if (ep->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 void
  usba_update_req(struct usba_ep *ep, struct usba_request *req, u32 status)
  {
  	req->req.actual = req->req.length - USBA_BFEXT(DMA_BUF_LEN, status);
  }
  
  static int stop_dma(struct usba_ep *ep, u32 *pstatus)
  {
  	unsigned int timeout;
  	u32 status;
  
  	/*
  	 * Stop the DMA controller. When writing both CH_EN
  	 * and LINK to 0, the other bits are not affected.
  	 */
  	usba_dma_writel(ep, CONTROL, 0);
  
  	/* Wait for the FIFO to empty */
  	for (timeout = 40; timeout; --timeout) {
  		status = usba_dma_readl(ep, STATUS);
  		if (!(status & USBA_DMA_CH_EN))
  			break;
  		udelay(1);
  	}
  
  	if (pstatus)
  		*pstatus = status;
  
  	if (timeout == 0) {
  		dev_err(&ep->udc->pdev->dev,
  			"%s: timed out waiting for DMA FIFO to empty
  ",
  			ep->ep.name);
  		return -ETIMEDOUT;
  	}
  
  	return 0;
  }
  
  static int usba_ep_dequeue(struct usb_ep *_ep, struct usb_request *_req)
  {
  	struct usba_ep *ep = to_usba_ep(_ep);
  	struct usba_udc *udc = ep->udc;

  	struct usba_request *req;

  	unsigned long flags;
  	u32 status;
  
  	DBG(DBG_GADGET | DBG_QUEUE, "ep_dequeue: %s, req %p
  ",
  			ep->ep.name, req);
  
  	spin_lock_irqsave(&udc->lock, flags);

  	list_for_each_entry(req, &ep->queue, queue) {
  		if (&req->req == _req)
  			break;
  	}
  
  	if (&req->req != _req) {
  		spin_unlock_irqrestore(&udc->lock, flags);
  		return -EINVAL;
  	}

  	if (req->using_dma) {
  		/*
  		 * If this request is currently being transferred,
  		 * stop the DMA controller and reset the FIFO.
  		 */
  		if (ep->queue.next == &req->queue) {
  			status = usba_dma_readl(ep, STATUS);
  			if (status & USBA_DMA_CH_EN)
  				stop_dma(ep, &status);
  
  #ifdef CONFIG_USB_GADGET_DEBUG_FS
  			ep->last_dma_status = status;
  #endif
  
  			usba_writel(udc, EPT_RST, 1 << ep->index);
  
  			usba_update_req(ep, req, status);
  		}
  	}
  
  	/*
  	 * 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);
  	spin_unlock_irqrestore(&udc->lock, flags);
  
  	return 0;
  }
  
  static int usba_ep_set_halt(struct usb_ep *_ep, int value)
  {
  	struct usba_ep *ep = to_usba_ep(_ep);
  	struct usba_udc *udc = ep->udc;
  	unsigned long flags;
  	int ret = 0;
  
  	DBG(DBG_GADGET, "endpoint %s: %s HALT
  ", ep->ep.name,
  			value ? "set" : "clear");

  	if (!ep->ep.desc) {

  		DBG(DBG_ERR, "Attempted to halt uninitialized ep %s
  ",
  				ep->ep.name);
  		return -ENODEV;
  	}
  	if (ep->is_isoc) {
  		DBG(DBG_ERR, "Attempted to halt isochronous ep %s
  ",
  				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 int atmel_usba_start(struct usb_gadget *gadget,
  		struct usb_gadget_driver *driver);
  static int atmel_usba_stop(struct usb_gadget *gadget,
  		struct usb_gadget_driver *driver);

  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,

  	.udc_start		= atmel_usba_start,
  	.udc_stop		= atmel_usba_stop,

  };

  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,
  };
  
  static void nop_release(struct device *dev)
  {
  
  }

  static struct usb_gadget usba_gadget_template = {

  	.ops		= &usba_udc_ops,
  	.max_speed	= USB_SPEED_HIGH,
  	.name		= "atmel_usba_udc",
  	.dev	= {
  		.init_name	= "gadget",
  		.release	= nop_release,

  	},

  };
  
  /*
   * 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->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->ep.desc)

  			continue;

  		bEndpointAddress = ep->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...
  ", 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;
  	struct device *dev = &udc->pdev->dev;
  	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);
  		dev_info(dev, "Entering Test_J mode...
  ");
  		break;
  	case 0x0200:
  		/* Test_K */
  		usba_writel(udc, TST, USBA_TST_K_MODE);
  		dev_info(dev, "Entering Test_K mode...
  ");
  		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);
  			dev_err(dev, "Test_SE0_NAK: ep0 not mapped
  ");
  		} else {
  			usba_ep_writel(ep, CTL_ENB, USBA_EPT_ENABLE);
  			dev_info(dev, "Entering Test_SE0_NAK mode...
  ");
  		}
  		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);
  			dev_err(dev, "Test_Packet: ep0 not mapped
  ");
  		} else {
  			usba_ep_writel(ep, CTL_ENB, USBA_EPT_ENABLE);
  			usba_writel(udc, TST, USBA_TST_PKT_MODE);

  			memcpy_toio(ep->fifo, test_packet_buffer,

  					sizeof(test_packet_buffer));
  			usba_ep_writel(ep, SET_STA, USBA_TX_PK_RDY);
  			dev_info(dev, "Entering Test_Packet mode...
  ");
  		}
  		break;
  	default:
  		dev_err(dev, "Invalid test mode: 0x%04x
  ", 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:

  	pr_err("udc: %s: Invalid setup request: %02x.%02x v%04x i%04x l%d, "

  		"halting endpoint...
  ",
  		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
  ",
  			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:

  			pr_err("udc: %s: TXCOMP: Invalid endpoint state %d, "

  				"halting endpoint...
  ",
  				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);

  			pr_err("udc: %s: RXRDY: Invalid endpoint state %d, "

  				"halting endpoint...
  ",
  				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
  ", pkt_len);
  		if (pkt_len != sizeof(crq)) {

  			pr_warning("udc: Invalid packet length %u "

  				"(expected %zu)
  ", pkt_len, sizeof(crq));

  			set_protocol_stall(udc, ep);
  			return;
  		}
  
  		DBG(DBG_FIFO, "Copying ctrl request from 0x%p:
  ", ep->fifo);

  		memcpy_fromio(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);
  
  		/* printk(KERN_DEBUG "setup: %d: %02x.%02x
  ",
  			ep->state, crq.crq.bRequestType,
  			crq.crq.bRequest); */
  
  		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
  ",
  			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
  ", ep->ep.name, epstatus);
  
  	while ((epctrl & USBA_TX_PK_RDY) && !(epstatus & USBA_TX_PK_RDY)) {
  		DBG(DBG_BUS, "%s: TX PK ready
  ", ep->ep.name);
  
  		if (list_empty(&ep->queue)) {
  			dev_warn(&udc->pdev->dev, "ep_irq: queue empty
  ");
  			usba_ep_writel(ep, CTL_DIS, USBA_TX_PK_RDY);
  			return;
  		}
  
  		req = list_entry(ep->queue.next, struct usba_request, queue);
  
  		if (req->using_dma) {
  			/* Send a zero-length packet */
  			usba_ep_writel(ep, SET_STA,
  					USBA_TX_PK_RDY);
  			usba_ep_writel(ep, CTL_DIS,
  					USBA_TX_PK_RDY);
  			list_del_init(&req->queue);
  			submit_next_request(ep);
  			request_complete(ep, req, 0);
  		} else {
  			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
  ", ep->ep.name);
  		receive_data(ep);

  	}
  }
  
  static void usba_dma_irq(struct usba_udc *udc, struct usba_ep *ep)
  {
  	struct usba_request *req;
  	u32 status, control, pending;
  
  	status = usba_dma_readl(ep, STATUS);
  	control = usba_dma_readl(ep, CONTROL);
  #ifdef CONFIG_USB_GADGET_DEBUG_FS
  	ep->last_dma_status = status;
  #endif
  	pending = status & control;
  	DBG(DBG_INT | DBG_DMA, "dma irq, s/%#08x, c/%#08x
  ", status, control);
  
  	if (status & USBA_DMA_CH_EN) {
  		dev_err(&udc->pdev->dev,
  			"DMA_CH_EN is set after transfer is finished!
  ");
  		dev_err(&udc->pdev->dev,
  			"status=%#08x, pending=%#08x, control=%#08x
  ",
  			status, pending, control);
  
  		/*
  		 * try to pretend nothing happened. We might have to
  		 * do something here...
  		 */
  	}
  
  	if (list_empty(&ep->queue))
  		/* Might happen if a reset comes along at the right moment */
  		return;
  
  	if (pending & (USBA_DMA_END_TR_ST | USBA_DMA_END_BUF_ST)) {
  		req = list_entry(ep->queue.next, struct usba_request, queue);
  		usba_update_req(ep, req, status);
  
  		list_del_init(&req->queue);
  		submit_next_request(ep);
  		request_complete(ep, req, 0);
  	}
  }
  
  static irqreturn_t usba_udc_irq(int irq, void *devid)
  {
  	struct usba_udc *udc = devid;
  	u32 status;
  	u32 dma_status;
  	u32 ep_status;
  
  	spin_lock(&udc->lock);
  
  	status = usba_readl(udc, INT_STA);
  	DBG(DBG_INT, "irq, status=%#08x
  ", status);
  
  	if (status & USBA_DET_SUSPEND) {

  		toggle_bias(0);

  		usba_writel(udc, INT_CLR, USBA_DET_SUSPEND);
  		DBG(DBG_BUS, "Suspend detected
  ");
  		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) {

  		toggle_bias(1);

  		usba_writel(udc, INT_CLR, USBA_WAKE_UP);
  		DBG(DBG_BUS, "Wake Up CPU detected
  ");
  	}
  
  	if (status & USBA_END_OF_RESUME) {
  		usba_writel(udc, INT_CLR, USBA_END_OF_RESUME);
  		DBG(DBG_BUS, "Resume detected
  ");
  		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);
  		}
  	}
  
  	dma_status = USBA_BFEXT(DMA_INT, status);
  	if (dma_status) {
  		int i;

  		for (i = 1; i <= USBA_NR_DMAS; i++)

  			if (dma_status & (1 << i))

  				usba_dma_irq(udc, &udc->usba_ep[i]);

  	}
  
  	ep_status = USBA_BFEXT(EPT_INT, status);
  	if (ep_status) {
  		int i;

  		for (i = 0; i < udc->num_ep; 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 && 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;

  		DBG(DBG_BUS, "%s bus reset detected
  ",
  		    usb_speed_string(udc->gadget.speed));

  		ep0 = &udc->usba_ep[0];

  		ep0->ep.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))

  			dev_dbg(&udc->pdev->dev,
  				 "ODD: EP0 configuration is invalid!
  ");

  	}
  
  	spin_unlock(&udc->lock);
  
  	return IRQ_HANDLED;
  }
  
  static irqreturn_t usba_vbus_irq(int irq, void *devid)
  {
  	struct usba_udc *udc = devid;
  	int vbus;
  
  	/* debounce */
  	udelay(10);
  
  	spin_lock(&udc->lock);
  
  	/* May happen if Vbus pin toggles during probe() */
  	if (!udc->driver)
  		goto out;

  	vbus = vbus_is_present(udc);

  	if (vbus != udc->vbus_prev) {
  		if (vbus) {

  			toggle_bias(1);
  			usba_writel(udc, CTRL, USBA_ENABLE_MASK);

  			usba_writel(udc, INT_ENB, USBA_END_OF_RESET);
  		} else {
  			udc->gadget.speed = USB_SPEED_UNKNOWN;
  			reset_all_endpoints(udc);

  			toggle_bias(0);
  			usba_writel(udc, CTRL, USBA_DISABLE_MASK);

  			if (udc->driver->disconnect) {
  				spin_unlock(&udc->lock);
  				udc->driver->disconnect(&udc->gadget);
  				spin_lock(&udc->lock);
  			}

  		}
  		udc->vbus_prev = vbus;
  	}
  
  out:
  	spin_unlock(&udc->lock);
  
  	return IRQ_HANDLED;
  }

  static int atmel_usba_start(struct usb_gadget *gadget,
  		struct usb_gadget_driver *driver)

  {

  	int ret;

  	struct usba_udc *udc = container_of(gadget, struct usba_udc, gadget);

  	unsigned long flags;

  
  	spin_lock_irqsave(&udc->lock, flags);

  	udc->devstatus = 1 << USB_DEVICE_SELF_POWERED;

  	udc->driver = driver;

  	spin_unlock_irqrestore(&udc->lock, flags);

  	ret = clk_prepare_enable(udc->pclk);
  	if (ret)

  		return ret;

  	ret = clk_prepare_enable(udc->hclk);
  	if (ret) {
  		clk_disable_unprepare(udc->pclk);

  		return ret;

  	}

  	DBG(DBG_GADGET, "registered driver `%s'
  ", driver->driver.name);
  
  	udc->vbus_prev = 0;

  	if (gpio_is_valid(udc->vbus_pin))

  		enable_irq(gpio_to_irq(udc->vbus_pin));
  
  	/* If Vbus is present, enable the controller and wait for reset */
  	spin_lock_irqsave(&udc->lock, flags);
  	if (vbus_is_present(udc) && udc->vbus_prev == 0) {

  		toggle_bias(1);
  		usba_writel(udc, CTRL, USBA_ENABLE_MASK);

  		usba_writel(udc, INT_ENB, USBA_END_OF_RESET);
  	}
  	spin_unlock_irqrestore(&udc->lock, flags);

  	return 0;

  }

  static int atmel_usba_stop(struct usb_gadget *gadget,
  		struct usb_gadget_driver *driver)

  {

  	struct usba_udc *udc = container_of(gadget, struct usba_udc, gadget);

  	unsigned long flags;

  	if (gpio_is_valid(udc->vbus_pin))

  		disable_irq(gpio_to_irq(udc->vbus_pin));
  
  	spin_lock_irqsave(&udc->lock, flags);
  	udc->gadget.speed = USB_SPEED_UNKNOWN;
  	reset_all_endpoints(udc);
  	spin_unlock_irqrestore(&udc->lock, flags);
  
  	/* This will also disable the DP pullup */

  	toggle_bias(0);
  	usba_writel(udc, CTRL, USBA_DISABLE_MASK);

  	clk_disable_unprepare(udc->hclk);
  	clk_disable_unprepare(udc->pclk);

  	DBG(DBG_GADGET, "unregistered driver `%s'
  ", udc->driver->driver.name);
  
  	udc->driver = NULL;

  
  	return 0;
  }

  #ifdef CONFIG_OF
  static struct usba_ep * atmel_udc_of_init(struct platform_device *pdev,
  						    struct usba_udc *udc)
  {
  	u32 val;
  	const char *name;
  	enum of_gpio_flags flags;
  	struct device_node *np = pdev->dev.of_node;
  	struct device_node *pp;
  	int i, ret;
  	struct usba_ep *eps, *ep;
  
  	udc->num_ep = 0;
  
  	udc->vbus_pin = of_get_named_gpio_flags(np, "atmel,vbus-gpio", 0,
  						&flags);
  	udc->vbus_pin_inverted = (flags & OF_GPIO_ACTIVE_LOW) ? 1 : 0;
  
  	pp = NULL;
  	while ((pp = of_get_next_child(np, pp)))
  		udc->num_ep++;
  
  	eps = devm_kzalloc(&pdev->dev, sizeof(struct usba_ep) * udc->num_ep,
  			   GFP_KERNEL);
  	if (!eps)
  		return ERR_PTR(-ENOMEM);
  
  	udc->gadget.ep0 = &eps[0].ep;
  
  	INIT_LIST_HEAD(&eps[0].ep.ep_list);
  
  	pp = NULL;
  	i = 0;
  	while ((pp = of_get_next_child(np, pp))) {
  		ep = &eps[i];
  
  		ret = of_property_read_u32(pp, "reg", &val);
  		if (ret) {
  			dev_err(&pdev->dev, "of_probe: reg error(%d)
  ", ret);
  			goto err;
  		}
  		ep->index = val;
  
  		ret = of_property_read_u32(pp, "atmel,fifo-size", &val);
  		if (ret) {
  			dev_err(&pdev->dev, "of_probe: fifo-size error(%d)
  ", ret);
  			goto err;
  		}
  		ep->fifo_size = val;
  
  		ret = of_property_read_u32(pp, "atmel,nb-banks", &val);
  		if (ret) {
  			dev_err(&pdev->dev, "of_probe: nb-banks error(%d)
  ", ret);
  			goto err;
  		}
  		ep->nr_banks = val;
  
  		ep->can_dma = of_property_read_bool(pp, "atmel,can-dma");
  		ep->can_isoc = of_property_read_bool(pp, "atmel,can-isoc");
  
  		ret = of_property_read_string(pp, "name", &name);
  		ep->ep.name = name;
  
  		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;

  		usb_ep_set_maxpacket_limit(&ep->ep, ep->fifo_size);

  		ep->udc = udc;
  		INIT_LIST_HEAD(&ep->queue);
  
  		if (i)
  			list_add_tail(&ep->ep.ep_list, &udc->gadget.ep_list);
  
  		i++;
  	}

  	if (i == 0) {
  		dev_err(&pdev->dev, "of_probe: no endpoint specified
  ");
  		ret = -EINVAL;
  		goto err;
  	}

  	return eps;
  err:
  	return ERR_PTR(ret);
  }
  #else
  static struct usba_ep * atmel_udc_of_init(struct platform_device *pdev,
  						    struct usba_udc *udc)
  {
  	return ERR_PTR(-ENOSYS);
  }
  #endif
  
  static struct usba_ep * usba_udc_pdata(struct platform_device *pdev,
  						 struct usba_udc *udc)

  {

  	struct usba_platform_data *pdata = dev_get_platdata(&pdev->dev);

  	struct usba_ep *eps;
  	int i;
  
  	if (!pdata)
  		return ERR_PTR(-ENXIO);
  
  	eps = devm_kzalloc(&pdev->dev, sizeof(struct usba_ep) * pdata->num_ep,
  			   GFP_KERNEL);
  	if (!eps)
  		return ERR_PTR(-ENOMEM);
  
  	udc->gadget.ep0 = &eps[0].ep;
  
  	udc->vbus_pin = pdata->vbus_pin;
  	udc->vbus_pin_inverted = pdata->vbus_pin_inverted;
  	udc->num_ep = pdata->num_ep;
  
  	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->fifo_size = pdata->ep[i].fifo_size;
  		usb_ep_set_maxpacket_limit(&ep->ep, ep->fifo_size);

  		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;
  }

  static int usba_udc_probe(struct platform_device *pdev)

  {

  	struct resource *regs, *fifo;
  	struct clk *pclk, *hclk;

  	struct usba_udc *udc;

  	int irq, ret, i;

  	udc = devm_kzalloc(&pdev->dev, sizeof(*udc), GFP_KERNEL);
  	if (!udc)
  		return -ENOMEM;
  
  	udc->gadget = usba_gadget_template;
  	INIT_LIST_HEAD(&udc->gadget.ep_list);

  	regs = platform_get_resource(pdev, IORESOURCE_MEM, CTRL_IOMEM_ID);
  	fifo = platform_get_resource(pdev, IORESOURCE_MEM, FIFO_IOMEM_ID);

  	if (!regs || !fifo)

  		return -ENXIO;
  
  	irq = platform_get_irq(pdev, 0);
  	if (irq < 0)
  		return irq;

  	pclk = devm_clk_get(&pdev->dev, "pclk");

  	if (IS_ERR(pclk))
  		return PTR_ERR(pclk);

  	hclk = devm_clk_get(&pdev->dev, "hclk");
  	if (IS_ERR(hclk))
  		return PTR_ERR(hclk);

  	spin_lock_init(&udc->lock);

  	udc->pdev = pdev;
  	udc->pclk = pclk;
  	udc->hclk = hclk;

  	udc->vbus_pin = -ENODEV;

  
  	ret = -ENOMEM;

  	udc->regs = devm_ioremap(&pdev->dev, regs->start, resource_size(regs));

  	if (!udc->regs) {
  		dev_err(&pdev->dev, "Unable to map I/O memory, aborting.
  ");

  		return ret;

  	}
  	dev_info(&pdev->dev, "MMIO registers at 0x%08lx mapped at %p
  ",
  		 (unsigned long)regs->start, udc->regs);

  	udc->fifo = devm_ioremap(&pdev->dev, fifo->start, resource_size(fifo));

  	if (!udc->fifo) {
  		dev_err(&pdev->dev, "Unable to map FIFO, aborting.
  ");

  		return ret;

  	}
  	dev_info(&pdev->dev, "FIFO at 0x%08lx mapped at %p
  ",
  		 (unsigned long)fifo->start, udc->fifo);

  	platform_set_drvdata(pdev, udc);
  
  	/* Make sure we start from a clean slate */

  	ret = clk_prepare_enable(pclk);
  	if (ret) {
  		dev_err(&pdev->dev, "Unable to enable pclk, aborting.
  ");

  		return ret;

  	}

  	toggle_bias(0);
  	usba_writel(udc, CTRL, USBA_DISABLE_MASK);

  	clk_disable_unprepare(pclk);

  	if (pdev->dev.of_node)
  		udc->usba_ep = atmel_udc_of_init(pdev, udc);
  	else
  		udc->usba_ep = usba_udc_pdata(pdev, udc);

  	if (IS_ERR(udc->usba_ep))
  		return PTR_ERR(udc->usba_ep);

  	ret = devm_request_irq(&pdev->dev, irq, usba_udc_irq, 0,
  				"atmel_usba_udc", udc);

  	if (ret) {
  		dev_err(&pdev->dev, "Cannot request irq %d (error %d)
  ",
  			irq, ret);

  		return ret;

  	}
  	udc->irq = irq;

  	if (gpio_is_valid(udc->vbus_pin)) {
  		if (!devm_gpio_request(&pdev->dev, udc->vbus_pin, "atmel_usba_udc")) {

  			ret = devm_request_irq(&pdev->dev,
  					gpio_to_irq(udc->vbus_pin),

  					usba_vbus_irq, 0,
  					"atmel_usba_udc", udc);
  			if (ret) {

  				udc->vbus_pin = -ENODEV;

  				dev_warn(&udc->pdev->dev,
  					 "failed to request vbus irq; "
  					 "assuming always on
  ");
  			} else {
  				disable_irq(gpio_to_irq(udc->vbus_pin));
  			}

  		} else {
  			/* gpio_request fail so use -EINVAL for gpio_is_valid */

  			udc->vbus_pin = -EINVAL;

  		}
  	}

  	ret = usb_add_gadget_udc(&pdev->dev, &udc->gadget);
  	if (ret)

  		return ret;

  	usba_init_debugfs(udc);

  	for (i = 1; i < udc->num_ep; i++)
  		usba_ep_init_debugfs(udc, &udc->usba_ep[i]);

  
  	return 0;

  }
  
  static int __exit usba_udc_remove(struct platform_device *pdev)
  {
  	struct usba_udc *udc;
  	int i;
  
  	udc = platform_get_drvdata(pdev);

  	usb_del_gadget_udc(&udc->gadget);

  	for (i = 1; i < udc->num_ep; i++)

  		usba_ep_cleanup_debugfs(&udc->usba_ep[i]);

  	usba_cleanup_debugfs(udc);

  	return 0;
  }

  #if defined(CONFIG_OF)
  static const struct of_device_id atmel_udc_dt_ids[] = {
  	{ .compatible = "atmel,at91sam9rl-udc" },
  	{ /* sentinel */ }
  };
  
  MODULE_DEVICE_TABLE(of, atmel_udc_dt_ids);
  #endif

  static struct platform_driver udc_driver = {
  	.remove		= __exit_p(usba_udc_remove),
  	.driver		= {
  		.name		= "atmel_usba_udc",

  		.owner		= THIS_MODULE,

  		.of_match_table	= of_match_ptr(atmel_udc_dt_ids),

  	},
  };

  module_platform_driver_probe(udc_driver, usba_udc_probe);

  
  MODULE_DESCRIPTION("Atmel USBA UDC driver");

  MODULE_AUTHOR("Haavard Skinnemoen (Atmel)");

  MODULE_LICENSE("GPL");

  MODULE_ALIAS("platform:atmel_usba_udc");