/*
   * Copyright (c) 2010-2011 Atheros Communications Inc.
   *
   * Permission to use, copy, modify, and/or distribute this software for any
   * purpose with or without fee is hereby granted, provided that the above
   * copyright notice and this permission notice appear in all copies.
   *
   * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
   * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
   * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
   * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
   * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
   * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
   * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
   */
  
  #include <asm/unaligned.h>
  #include "htc.h"
  
  MODULE_FIRMWARE(HTC_7010_MODULE_FW);
  MODULE_FIRMWARE(HTC_9271_MODULE_FW);
  
  static struct usb_device_id ath9k_hif_usb_ids[] = {
  	{ USB_DEVICE(0x0cf3, 0x9271) }, /* Atheros */
  	{ USB_DEVICE(0x0cf3, 0x1006) }, /* Atheros */
  	{ USB_DEVICE(0x0846, 0x9030) }, /* Netgear N150 */
  	{ USB_DEVICE(0x07D1, 0x3A10) }, /* Dlink Wireless 150 */
  	{ USB_DEVICE(0x13D3, 0x3327) }, /* Azurewave */
  	{ USB_DEVICE(0x13D3, 0x3328) }, /* Azurewave */
  	{ USB_DEVICE(0x13D3, 0x3346) }, /* IMC Networks */
  	{ USB_DEVICE(0x13D3, 0x3348) }, /* Azurewave */
  	{ USB_DEVICE(0x13D3, 0x3349) }, /* Azurewave */
  	{ USB_DEVICE(0x13D3, 0x3350) }, /* Azurewave */
  	{ USB_DEVICE(0x04CA, 0x4605) }, /* Liteon */
  	{ USB_DEVICE(0x040D, 0x3801) }, /* VIA */
  	{ USB_DEVICE(0x0cf3, 0xb003) }, /* Ubiquiti WifiStation Ext */
  	{ USB_DEVICE(0x0cf3, 0xb002) }, /* Ubiquiti WifiStation */
  	{ USB_DEVICE(0x057c, 0x8403) }, /* AVM FRITZ!WLAN 11N v2 USB */
  	{ USB_DEVICE(0x0471, 0x209e) }, /* Philips (or NXP) PTA01 */
  
  	{ USB_DEVICE(0x0cf3, 0x7015),
  	  .driver_info = AR9287_USB },  /* Atheros */
  	{ USB_DEVICE(0x1668, 0x1200),
  	  .driver_info = AR9287_USB },  /* Verizon */
  
  	{ USB_DEVICE(0x0cf3, 0x7010),
  	  .driver_info = AR9280_USB },  /* Atheros */
  	{ USB_DEVICE(0x0846, 0x9018),
  	  .driver_info = AR9280_USB },  /* Netgear WNDA3200 */
  	{ USB_DEVICE(0x083A, 0xA704),
  	  .driver_info = AR9280_USB },  /* SMC Networks */
  	{ USB_DEVICE(0x0411, 0x017f),
  	  .driver_info = AR9280_USB },  /* Sony UWA-BR100 */
  	{ USB_DEVICE(0x0411, 0x0197),
  	  .driver_info = AR9280_USB },  /* Buffalo WLI-UV-AG300P */
  	{ USB_DEVICE(0x04da, 0x3904),
  	  .driver_info = AR9280_USB },
  
  	{ USB_DEVICE(0x0cf3, 0x20ff),
  	  .driver_info = STORAGE_DEVICE },
  
  	{ },
  };
  
  MODULE_DEVICE_TABLE(usb, ath9k_hif_usb_ids);
  
  static int __hif_usb_tx(struct hif_device_usb *hif_dev);
  
  static void hif_usb_regout_cb(struct urb *urb)
  {
  	struct cmd_buf *cmd = (struct cmd_buf *)urb->context;
  
  	switch (urb->status) {
  	case 0:
  		break;
  	case -ENOENT:
  	case -ECONNRESET:
  	case -ENODEV:
  	case -ESHUTDOWN:
  		goto free;
  	default:
  		break;
  	}
  
  	if (cmd) {
  		ath9k_htc_txcompletion_cb(cmd->hif_dev->htc_handle,
  					  cmd->skb, true);
  		kfree(cmd);
  	}
  
  	return;
  free:
  	kfree_skb(cmd->skb);
  	kfree(cmd);
  }
  
  static int hif_usb_send_regout(struct hif_device_usb *hif_dev,
  			       struct sk_buff *skb)
  {
  	struct urb *urb;
  	struct cmd_buf *cmd;
  	int ret = 0;
  
  	urb = usb_alloc_urb(0, GFP_KERNEL);
  	if (urb == NULL)
  		return -ENOMEM;
  
  	cmd = kzalloc(sizeof(*cmd), GFP_KERNEL);
  	if (cmd == NULL) {
  		usb_free_urb(urb);
  		return -ENOMEM;
  	}
  
  	cmd->skb = skb;
  	cmd->hif_dev = hif_dev;
  
  	usb_fill_int_urb(urb, hif_dev->udev,
  			 usb_sndintpipe(hif_dev->udev, USB_REG_OUT_PIPE),
  			 skb->data, skb->len,
  			 hif_usb_regout_cb, cmd, 1);
  
  	usb_anchor_urb(urb, &hif_dev->regout_submitted);
  	ret = usb_submit_urb(urb, GFP_KERNEL);
  	if (ret) {
  		usb_unanchor_urb(urb);
  		kfree(cmd);
  	}
  	usb_free_urb(urb);
  
  	return ret;
  }
  
  static void hif_usb_mgmt_cb(struct urb *urb)
  {
  	struct cmd_buf *cmd = (struct cmd_buf *)urb->context;
  	struct hif_device_usb *hif_dev;
  	bool txok = true;
  
  	if (!cmd || !cmd->skb || !cmd->hif_dev)
  		return;
  
  	hif_dev = cmd->hif_dev;
  
  	switch (urb->status) {
  	case 0:
  		break;
  	case -ENOENT:
  	case -ECONNRESET:
  	case -ENODEV:
  	case -ESHUTDOWN:
  		txok = false;
  
  		/*
  		 * If the URBs are being flushed, no need to complete
  		 * this packet.
  		 */
  		spin_lock(&hif_dev->tx.tx_lock);
  		if (hif_dev->tx.flags & HIF_USB_TX_FLUSH) {
  			spin_unlock(&hif_dev->tx.tx_lock);
  			dev_kfree_skb_any(cmd->skb);
  			kfree(cmd);
  			return;
  		}
  		spin_unlock(&hif_dev->tx.tx_lock);
  
  		break;
  	default:
  		txok = false;
  		break;
  	}
  
  	skb_pull(cmd->skb, 4);
  	ath9k_htc_txcompletion_cb(cmd->hif_dev->htc_handle,
  				  cmd->skb, txok);
  	kfree(cmd);
  }
  
  static int hif_usb_send_mgmt(struct hif_device_usb *hif_dev,
  			     struct sk_buff *skb)
  {
  	struct urb *urb;
  	struct cmd_buf *cmd;
  	int ret = 0;
  	__le16 *hdr;
  
  	urb = usb_alloc_urb(0, GFP_ATOMIC);
  	if (urb == NULL)
  		return -ENOMEM;
  
  	cmd = kzalloc(sizeof(*cmd), GFP_ATOMIC);
  	if (cmd == NULL) {
  		usb_free_urb(urb);
  		return -ENOMEM;
  	}
  
  	cmd->skb = skb;
  	cmd->hif_dev = hif_dev;
  
  	hdr = (__le16 *) skb_push(skb, 4);
  	*hdr++ = cpu_to_le16(skb->len - 4);
  	*hdr++ = cpu_to_le16(ATH_USB_TX_STREAM_MODE_TAG);
  
  	usb_fill_bulk_urb(urb, hif_dev->udev,
  			 usb_sndbulkpipe(hif_dev->udev, USB_WLAN_TX_PIPE),
  			 skb->data, skb->len,
  			 hif_usb_mgmt_cb, cmd);
  
  	usb_anchor_urb(urb, &hif_dev->mgmt_submitted);
  	ret = usb_submit_urb(urb, GFP_ATOMIC);
  	if (ret) {
  		usb_unanchor_urb(urb);
  		kfree(cmd);
  	}
  	usb_free_urb(urb);
  
  	return ret;
  }
  
  static inline void ath9k_skb_queue_purge(struct hif_device_usb *hif_dev,
  					 struct sk_buff_head *list)
  {
  	struct sk_buff *skb;
  
  	while ((skb = __skb_dequeue(list)) != NULL) {
  		dev_kfree_skb_any(skb);
  	}
  }
  
  static inline void ath9k_skb_queue_complete(struct hif_device_usb *hif_dev,
  					    struct sk_buff_head *queue,
  					    bool txok)
  {
  	struct sk_buff *skb;
  
  	while ((skb = __skb_dequeue(queue)) != NULL) {
  #ifdef CONFIG_ATH9K_HTC_DEBUGFS
  		int ln = skb->len;
  #endif
  		ath9k_htc_txcompletion_cb(hif_dev->htc_handle,
  					  skb, txok);
  		if (txok) {
  			TX_STAT_INC(skb_success);
  			TX_STAT_ADD(skb_success_bytes, ln);
  		}
  		else
  			TX_STAT_INC(skb_failed);
  	}
  }
  
  static void hif_usb_tx_cb(struct urb *urb)
  {
  	struct tx_buf *tx_buf = (struct tx_buf *) urb->context;
  	struct hif_device_usb *hif_dev;
  	bool txok = true;
  
  	if (!tx_buf || !tx_buf->hif_dev)
  		return;
  
  	hif_dev = tx_buf->hif_dev;
  
  	switch (urb->status) {
  	case 0:
  		break;
  	case -ENOENT:
  	case -ECONNRESET:
  	case -ENODEV:
  	case -ESHUTDOWN:
  		txok = false;
  
  		/*
  		 * If the URBs are being flushed, no need to add this
  		 * URB to the free list.
  		 */
  		spin_lock(&hif_dev->tx.tx_lock);
  		if (hif_dev->tx.flags & HIF_USB_TX_FLUSH) {
  			spin_unlock(&hif_dev->tx.tx_lock);
  			ath9k_skb_queue_purge(hif_dev, &tx_buf->skb_queue);
  			return;
  		}
  		spin_unlock(&hif_dev->tx.tx_lock);
  
  		break;
  	default:
  		txok = false;
  		break;
  	}
  
  	ath9k_skb_queue_complete(hif_dev, &tx_buf->skb_queue, txok);
  
  	/* Re-initialize the SKB queue */
  	tx_buf->len = tx_buf->offset = 0;
  	__skb_queue_head_init(&tx_buf->skb_queue);
  
  	/* Add this TX buffer to the free list */
  	spin_lock(&hif_dev->tx.tx_lock);
  	list_move_tail(&tx_buf->list, &hif_dev->tx.tx_buf);
  	hif_dev->tx.tx_buf_cnt++;
  	if (!(hif_dev->tx.flags & HIF_USB_TX_STOP))
  		__hif_usb_tx(hif_dev); /* Check for pending SKBs */
  	TX_STAT_INC(buf_completed);
  	spin_unlock(&hif_dev->tx.tx_lock);
  }
  
  /* TX lock has to be taken */
  static int __hif_usb_tx(struct hif_device_usb *hif_dev)
  {
  	struct tx_buf *tx_buf = NULL;
  	struct sk_buff *nskb = NULL;
  	int ret = 0, i;
  	u16 tx_skb_cnt = 0;
  	u8 *buf;
  	__le16 *hdr;
  
  	if (hif_dev->tx.tx_skb_cnt == 0)
  		return 0;
  
  	/* Check if a free TX buffer is available */
  	if (list_empty(&hif_dev->tx.tx_buf))
  		return 0;
  
  	tx_buf = list_first_entry(&hif_dev->tx.tx_buf, struct tx_buf, list);
  	list_move_tail(&tx_buf->list, &hif_dev->tx.tx_pending);
  	hif_dev->tx.tx_buf_cnt--;
  
  	tx_skb_cnt = min_t(u16, hif_dev->tx.tx_skb_cnt, MAX_TX_AGGR_NUM);
  
  	for (i = 0; i < tx_skb_cnt; i++) {
  		nskb = __skb_dequeue(&hif_dev->tx.tx_skb_queue);
  
  		/* Should never be NULL */
  		BUG_ON(!nskb);
  
  		hif_dev->tx.tx_skb_cnt--;
  
  		buf = tx_buf->buf;
  		buf += tx_buf->offset;
  		hdr = (__le16 *)buf;
  		*hdr++ = cpu_to_le16(nskb->len);
  		*hdr++ = cpu_to_le16(ATH_USB_TX_STREAM_MODE_TAG);
  		buf += 4;
  		memcpy(buf, nskb->data, nskb->len);
  		tx_buf->len = nskb->len + 4;
  
  		if (i < (tx_skb_cnt - 1))
  			tx_buf->offset += (((tx_buf->len - 1) / 4) + 1) * 4;
  
  		if (i == (tx_skb_cnt - 1))
  			tx_buf->len += tx_buf->offset;
  
  		__skb_queue_tail(&tx_buf->skb_queue, nskb);
  		TX_STAT_INC(skb_queued);
  	}
  
  	usb_fill_bulk_urb(tx_buf->urb, hif_dev->udev,
  			  usb_sndbulkpipe(hif_dev->udev, USB_WLAN_TX_PIPE),
  			  tx_buf->buf, tx_buf->len,
  			  hif_usb_tx_cb, tx_buf);
  
  	ret = usb_submit_urb(tx_buf->urb, GFP_ATOMIC);
  	if (ret) {
  		tx_buf->len = tx_buf->offset = 0;
  		ath9k_skb_queue_complete(hif_dev, &tx_buf->skb_queue, false);
  		__skb_queue_head_init(&tx_buf->skb_queue);
  		list_move_tail(&tx_buf->list, &hif_dev->tx.tx_buf);
  		hif_dev->tx.tx_buf_cnt++;
  	}
  
  	if (!ret)
  		TX_STAT_INC(buf_queued);
  
  	return ret;
  }
  
  static int hif_usb_send_tx(struct hif_device_usb *hif_dev, struct sk_buff *skb)
  {
  	struct ath9k_htc_tx_ctl *tx_ctl;
  	unsigned long flags;
  	int ret = 0;
  
  	spin_lock_irqsave(&hif_dev->tx.tx_lock, flags);
  
  	if (hif_dev->tx.flags & HIF_USB_TX_STOP) {
  		spin_unlock_irqrestore(&hif_dev->tx.tx_lock, flags);
  		return -ENODEV;
  	}
  
  	/* Check if the max queue count has been reached */
  	if (hif_dev->tx.tx_skb_cnt > MAX_TX_BUF_NUM) {
  		spin_unlock_irqrestore(&hif_dev->tx.tx_lock, flags);
  		return -ENOMEM;
  	}
  
  	spin_unlock_irqrestore(&hif_dev->tx.tx_lock, flags);
  
  	tx_ctl = HTC_SKB_CB(skb);
  
  	/* Mgmt/Beacon frames don't use the TX buffer pool */
  	if ((tx_ctl->type == ATH9K_HTC_MGMT) ||
  	    (tx_ctl->type == ATH9K_HTC_BEACON)) {
  		ret = hif_usb_send_mgmt(hif_dev, skb);
  	}
  
  	spin_lock_irqsave(&hif_dev->tx.tx_lock, flags);
  
  	if ((tx_ctl->type == ATH9K_HTC_NORMAL) ||
  	    (tx_ctl->type == ATH9K_HTC_AMPDU)) {
  		__skb_queue_tail(&hif_dev->tx.tx_skb_queue, skb);
  		hif_dev->tx.tx_skb_cnt++;
  	}
  
  	/* Check if AMPDUs have to be sent immediately */
  	if ((hif_dev->tx.tx_buf_cnt == MAX_TX_URB_NUM) &&
  	    (hif_dev->tx.tx_skb_cnt < 2)) {
  		__hif_usb_tx(hif_dev);
  	}
  
  	spin_unlock_irqrestore(&hif_dev->tx.tx_lock, flags);
  
  	return ret;
  }
  
  static void hif_usb_start(void *hif_handle)
  {
  	struct hif_device_usb *hif_dev = (struct hif_device_usb *)hif_handle;
  	unsigned long flags;
  
  	hif_dev->flags |= HIF_USB_START;
  
  	spin_lock_irqsave(&hif_dev->tx.tx_lock, flags);
  	hif_dev->tx.flags &= ~HIF_USB_TX_STOP;
  	spin_unlock_irqrestore(&hif_dev->tx.tx_lock, flags);
  }
  
  static void hif_usb_stop(void *hif_handle)
  {
  	struct hif_device_usb *hif_dev = (struct hif_device_usb *)hif_handle;
  	struct tx_buf *tx_buf = NULL, *tx_buf_tmp = NULL;
  	unsigned long flags;
  
  	spin_lock_irqsave(&hif_dev->tx.tx_lock, flags);
  	ath9k_skb_queue_complete(hif_dev, &hif_dev->tx.tx_skb_queue, false);
  	hif_dev->tx.tx_skb_cnt = 0;
  	hif_dev->tx.flags |= HIF_USB_TX_STOP;
  	spin_unlock_irqrestore(&hif_dev->tx.tx_lock, flags);
  
  	/* The pending URBs have to be canceled. */
  	list_for_each_entry_safe(tx_buf, tx_buf_tmp,
  				 &hif_dev->tx.tx_pending, list) {
  		usb_kill_urb(tx_buf->urb);
  	}
  
  	usb_kill_anchored_urbs(&hif_dev->mgmt_submitted);
  }
  
  static int hif_usb_send(void *hif_handle, u8 pipe_id, struct sk_buff *skb)
  {
  	struct hif_device_usb *hif_dev = (struct hif_device_usb *)hif_handle;
  	int ret = 0;
  
  	switch (pipe_id) {
  	case USB_WLAN_TX_PIPE:
  		ret = hif_usb_send_tx(hif_dev, skb);
  		break;
  	case USB_REG_OUT_PIPE:
  		ret = hif_usb_send_regout(hif_dev, skb);
  		break;
  	default:
  		dev_err(&hif_dev->udev->dev,
  			"ath9k_htc: Invalid TX pipe: %d
  ", pipe_id);
  		ret = -EINVAL;
  		break;
  	}
  
  	return ret;
  }
  
  static inline bool check_index(struct sk_buff *skb, u8 idx)
  {
  	struct ath9k_htc_tx_ctl *tx_ctl;
  
  	tx_ctl = HTC_SKB_CB(skb);
  
  	if ((tx_ctl->type == ATH9K_HTC_AMPDU) &&
  	    (tx_ctl->sta_idx == idx))
  		return true;
  
  	return false;
  }
  
  static void hif_usb_sta_drain(void *hif_handle, u8 idx)
  {
  	struct hif_device_usb *hif_dev = (struct hif_device_usb *)hif_handle;
  	struct sk_buff *skb, *tmp;
  	unsigned long flags;
  
  	spin_lock_irqsave(&hif_dev->tx.tx_lock, flags);
  
  	skb_queue_walk_safe(&hif_dev->tx.tx_skb_queue, skb, tmp) {
  		if (check_index(skb, idx)) {
  			__skb_unlink(skb, &hif_dev->tx.tx_skb_queue);
  			ath9k_htc_txcompletion_cb(hif_dev->htc_handle,
  						  skb, false);
  			hif_dev->tx.tx_skb_cnt--;
  			TX_STAT_INC(skb_failed);
  		}
  	}
  
  	spin_unlock_irqrestore(&hif_dev->tx.tx_lock, flags);
  }
  
  static struct ath9k_htc_hif hif_usb = {
  	.transport = ATH9K_HIF_USB,
  	.name = "ath9k_hif_usb",
  
  	.control_ul_pipe = USB_REG_OUT_PIPE,
  	.control_dl_pipe = USB_REG_IN_PIPE,
  
  	.start = hif_usb_start,
  	.stop = hif_usb_stop,
  	.sta_drain = hif_usb_sta_drain,
  	.send = hif_usb_send,
  };
  
  static void ath9k_hif_usb_rx_stream(struct hif_device_usb *hif_dev,
  				    struct sk_buff *skb)
  {
  	struct sk_buff *nskb, *skb_pool[MAX_PKT_NUM_IN_TRANSFER];
  	int index = 0, i = 0, len = skb->len;
  	int rx_remain_len, rx_pkt_len;
  	u16 pool_index = 0;
  	u8 *ptr;
  
  	spin_lock(&hif_dev->rx_lock);
  
  	rx_remain_len = hif_dev->rx_remain_len;
  	rx_pkt_len = hif_dev->rx_transfer_len;
  
  	if (rx_remain_len != 0) {
  		struct sk_buff *remain_skb = hif_dev->remain_skb;
  
  		if (remain_skb) {
  			ptr = (u8 *) remain_skb->data;
  
  			index = rx_remain_len;
  			rx_remain_len -= hif_dev->rx_pad_len;
  			ptr += rx_pkt_len;
  
  			memcpy(ptr, skb->data, rx_remain_len);
  
  			rx_pkt_len += rx_remain_len;
  			hif_dev->rx_remain_len = 0;
  			skb_put(remain_skb, rx_pkt_len);
  
  			skb_pool[pool_index++] = remain_skb;
  
  		} else {
  			index = rx_remain_len;
  		}
  	}
  
  	spin_unlock(&hif_dev->rx_lock);
  
  	while (index < len) {
  		u16 pkt_len;
  		u16 pkt_tag;
  		u16 pad_len;
  		int chk_idx;
  
  		ptr = (u8 *) skb->data;
  
  		pkt_len = get_unaligned_le16(ptr + index);
  		pkt_tag = get_unaligned_le16(ptr + index + 2);
  
  		if (pkt_tag != ATH_USB_RX_STREAM_MODE_TAG) {
  			RX_STAT_INC(skb_dropped);
  			return;
  		}
  
  		pad_len = 4 - (pkt_len & 0x3);
  		if (pad_len == 4)
  			pad_len = 0;
  
  		chk_idx = index;
  		index = index + 4 + pkt_len + pad_len;
  
  		if (index > MAX_RX_BUF_SIZE) {
  			spin_lock(&hif_dev->rx_lock);
  			hif_dev->rx_remain_len = index - MAX_RX_BUF_SIZE;
  			hif_dev->rx_transfer_len =
  				MAX_RX_BUF_SIZE - chk_idx - 4;
  			hif_dev->rx_pad_len = pad_len;
  
  			nskb = __dev_alloc_skb(pkt_len + 32, GFP_ATOMIC);
  			if (!nskb) {
  				dev_err(&hif_dev->udev->dev,
  					"ath9k_htc: RX memory allocation error
  ");
  				spin_unlock(&hif_dev->rx_lock);
  				goto err;
  			}
  			skb_reserve(nskb, 32);
  			RX_STAT_INC(skb_allocated);
  
  			memcpy(nskb->data, &(skb->data[chk_idx+4]),
  			       hif_dev->rx_transfer_len);
  
  			/* Record the buffer pointer */
  			hif_dev->remain_skb = nskb;
  			spin_unlock(&hif_dev->rx_lock);
  		} else {
  			nskb = __dev_alloc_skb(pkt_len + 32, GFP_ATOMIC);
  			if (!nskb) {
  				dev_err(&hif_dev->udev->dev,
  					"ath9k_htc: RX memory allocation error
  ");
  				goto err;
  			}
  			skb_reserve(nskb, 32);
  			RX_STAT_INC(skb_allocated);
  
  			memcpy(nskb->data, &(skb->data[chk_idx+4]), pkt_len);
  			skb_put(nskb, pkt_len);
  			skb_pool[pool_index++] = nskb;
  		}
  	}
  
  err:
  	for (i = 0; i < pool_index; i++) {
  		RX_STAT_ADD(skb_completed_bytes, skb_pool[i]->len);
  		ath9k_htc_rx_msg(hif_dev->htc_handle, skb_pool[i],
  				 skb_pool[i]->len, USB_WLAN_RX_PIPE);
  		RX_STAT_INC(skb_completed);
  	}
  }
  
  static void ath9k_hif_usb_rx_cb(struct urb *urb)
  {
  	struct sk_buff *skb = (struct sk_buff *) urb->context;
  	struct hif_device_usb *hif_dev =
  		usb_get_intfdata(usb_ifnum_to_if(urb->dev, 0));
  	int ret;
  
  	if (!skb)
  		return;
  
  	if (!hif_dev)
  		goto free;
  
  	switch (urb->status) {
  	case 0:
  		break;
  	case -ENOENT:
  	case -ECONNRESET:
  	case -ENODEV:
  	case -ESHUTDOWN:
  		goto free;
  	default:
  		goto resubmit;
  	}
  
  	if (likely(urb->actual_length != 0)) {
  		skb_put(skb, urb->actual_length);
  		ath9k_hif_usb_rx_stream(hif_dev, skb);
  	}
  
  resubmit:
  	skb_reset_tail_pointer(skb);
  	skb_trim(skb, 0);
  
  	usb_anchor_urb(urb, &hif_dev->rx_submitted);
  	ret = usb_submit_urb(urb, GFP_ATOMIC);
  	if (ret) {
  		usb_unanchor_urb(urb);
  		goto free;
  	}
  
  	return;
  free:
  	kfree_skb(skb);
  }
  
  static void ath9k_hif_usb_reg_in_cb(struct urb *urb)
  {
  	struct sk_buff *skb = (struct sk_buff *) urb->context;
  	struct sk_buff *nskb;
  	struct hif_device_usb *hif_dev =
  		usb_get_intfdata(usb_ifnum_to_if(urb->dev, 0));
  	int ret;
  
  	if (!skb)
  		return;
  
  	if (!hif_dev)
  		goto free;
  
  	switch (urb->status) {
  	case 0:
  		break;
  	case -ENOENT:
  	case -ECONNRESET:
  	case -ENODEV:
  	case -ESHUTDOWN:
  		goto free;
  	default:
  		skb_reset_tail_pointer(skb);
  		skb_trim(skb, 0);
  
  		goto resubmit;
  	}
  
  	if (likely(urb->actual_length != 0)) {
  		skb_put(skb, urb->actual_length);
  
  		/* Process the command first */
  		ath9k_htc_rx_msg(hif_dev->htc_handle, skb,
  				 skb->len, USB_REG_IN_PIPE);
  
  
  		nskb = alloc_skb(MAX_REG_IN_BUF_SIZE, GFP_ATOMIC);
  		if (!nskb) {
  			dev_err(&hif_dev->udev->dev,
  				"ath9k_htc: REG_IN memory allocation failure
  ");
  			urb->context = NULL;
  			return;
  		}
  
  		usb_fill_int_urb(urb, hif_dev->udev,
  				 usb_rcvintpipe(hif_dev->udev,
  						 USB_REG_IN_PIPE),
  				 nskb->data, MAX_REG_IN_BUF_SIZE,
  				 ath9k_hif_usb_reg_in_cb, nskb, 1);
  	}
  
  resubmit:
  	usb_anchor_urb(urb, &hif_dev->reg_in_submitted);
  	ret = usb_submit_urb(urb, GFP_ATOMIC);
  	if (ret) {
  		usb_unanchor_urb(urb);
  		goto free;
  	}
  
  	return;
  free:
  	kfree_skb(skb);
  	urb->context = NULL;
  }
  
  static void ath9k_hif_usb_dealloc_tx_urbs(struct hif_device_usb *hif_dev)
  {
  	struct tx_buf *tx_buf = NULL, *tx_buf_tmp = NULL;
  	unsigned long flags;
  
  	list_for_each_entry_safe(tx_buf, tx_buf_tmp,
  				 &hif_dev->tx.tx_buf, list) {
  		usb_kill_urb(tx_buf->urb);
  		list_del(&tx_buf->list);
  		usb_free_urb(tx_buf->urb);
  		kfree(tx_buf->buf);
  		kfree(tx_buf);
  	}
  
  	spin_lock_irqsave(&hif_dev->tx.tx_lock, flags);
  	hif_dev->tx.flags |= HIF_USB_TX_FLUSH;
  	spin_unlock_irqrestore(&hif_dev->tx.tx_lock, flags);
  
  	list_for_each_entry_safe(tx_buf, tx_buf_tmp,
  				 &hif_dev->tx.tx_pending, list) {
  		usb_kill_urb(tx_buf->urb);
  		list_del(&tx_buf->list);
  		usb_free_urb(tx_buf->urb);
  		kfree(tx_buf->buf);
  		kfree(tx_buf);
  	}
  
  	usb_kill_anchored_urbs(&hif_dev->mgmt_submitted);
  }
  
  static int ath9k_hif_usb_alloc_tx_urbs(struct hif_device_usb *hif_dev)
  {
  	struct tx_buf *tx_buf;
  	int i;
  
  	INIT_LIST_HEAD(&hif_dev->tx.tx_buf);
  	INIT_LIST_HEAD(&hif_dev->tx.tx_pending);
  	spin_lock_init(&hif_dev->tx.tx_lock);
  	__skb_queue_head_init(&hif_dev->tx.tx_skb_queue);
  	init_usb_anchor(&hif_dev->mgmt_submitted);
  
  	for (i = 0; i < MAX_TX_URB_NUM; i++) {
  		tx_buf = kzalloc(sizeof(struct tx_buf), GFP_KERNEL);
  		if (!tx_buf)
  			goto err;
  
  		tx_buf->buf = kzalloc(MAX_TX_BUF_SIZE, GFP_KERNEL);
  		if (!tx_buf->buf)
  			goto err;
  
  		tx_buf->urb = usb_alloc_urb(0, GFP_KERNEL);
  		if (!tx_buf->urb)
  			goto err;
  
  		tx_buf->hif_dev = hif_dev;
  		__skb_queue_head_init(&tx_buf->skb_queue);
  
  		list_add_tail(&tx_buf->list, &hif_dev->tx.tx_buf);
  	}
  
  	hif_dev->tx.tx_buf_cnt = MAX_TX_URB_NUM;
  
  	return 0;
  err:
  	if (tx_buf) {
  		kfree(tx_buf->buf);
  		kfree(tx_buf);
  	}
  	ath9k_hif_usb_dealloc_tx_urbs(hif_dev);
  	return -ENOMEM;
  }
  
  static void ath9k_hif_usb_dealloc_rx_urbs(struct hif_device_usb *hif_dev)
  {
  	usb_kill_anchored_urbs(&hif_dev->rx_submitted);
  }
  
  static int ath9k_hif_usb_alloc_rx_urbs(struct hif_device_usb *hif_dev)
  {
  	struct urb *urb = NULL;
  	struct sk_buff *skb = NULL;
  	int i, ret;
  
  	init_usb_anchor(&hif_dev->rx_submitted);
  	spin_lock_init(&hif_dev->rx_lock);
  
  	for (i = 0; i < MAX_RX_URB_NUM; i++) {
  
  		/* Allocate URB */
  		urb = usb_alloc_urb(0, GFP_KERNEL);
  		if (urb == NULL) {
  			ret = -ENOMEM;
  			goto err_urb;
  		}
  
  		/* Allocate buffer */
  		skb = alloc_skb(MAX_RX_BUF_SIZE, GFP_KERNEL);
  		if (!skb) {
  			ret = -ENOMEM;
  			goto err_skb;
  		}
  
  		usb_fill_bulk_urb(urb, hif_dev->udev,
  				  usb_rcvbulkpipe(hif_dev->udev,
  						  USB_WLAN_RX_PIPE),
  				  skb->data, MAX_RX_BUF_SIZE,
  				  ath9k_hif_usb_rx_cb, skb);
  
  		/* Anchor URB */
  		usb_anchor_urb(urb, &hif_dev->rx_submitted);
  
  		/* Submit URB */
  		ret = usb_submit_urb(urb, GFP_KERNEL);
  		if (ret) {
  			usb_unanchor_urb(urb);
  			goto err_submit;
  		}
  
  		/*
  		 * Drop reference count.
  		 * This ensures that the URB is freed when killing them.
  		 */
  		usb_free_urb(urb);
  	}
  
  	return 0;
  
  err_submit:
  	kfree_skb(skb);
  err_skb:
  	usb_free_urb(urb);
  err_urb:
  	ath9k_hif_usb_dealloc_rx_urbs(hif_dev);
  	return ret;
  }
  
  static void ath9k_hif_usb_dealloc_reg_in_urbs(struct hif_device_usb *hif_dev)
  {
  	usb_kill_anchored_urbs(&hif_dev->reg_in_submitted);
  }
  
  static int ath9k_hif_usb_alloc_reg_in_urbs(struct hif_device_usb *hif_dev)
  {
  	struct urb *urb = NULL;
  	struct sk_buff *skb = NULL;
  	int i, ret;
  
  	init_usb_anchor(&hif_dev->reg_in_submitted);
  
  	for (i = 0; i < MAX_REG_IN_URB_NUM; i++) {
  
  		/* Allocate URB */
  		urb = usb_alloc_urb(0, GFP_KERNEL);
  		if (urb == NULL) {
  			ret = -ENOMEM;
  			goto err_urb;
  		}
  
  		/* Allocate buffer */
  		skb = alloc_skb(MAX_REG_IN_BUF_SIZE, GFP_KERNEL);
  		if (!skb) {
  			ret = -ENOMEM;
  			goto err_skb;
  		}
  
  		usb_fill_int_urb(urb, hif_dev->udev,
  				  usb_rcvintpipe(hif_dev->udev,
  						  USB_REG_IN_PIPE),
  				  skb->data, MAX_REG_IN_BUF_SIZE,
  				  ath9k_hif_usb_reg_in_cb, skb, 1);
  
  		/* Anchor URB */
  		usb_anchor_urb(urb, &hif_dev->reg_in_submitted);
  
  		/* Submit URB */
  		ret = usb_submit_urb(urb, GFP_KERNEL);
  		if (ret) {
  			usb_unanchor_urb(urb);
  			goto err_submit;
  		}
  
  		/*
  		 * Drop reference count.
  		 * This ensures that the URB is freed when killing them.
  		 */
  		usb_free_urb(urb);
  	}
  
  	return 0;
  
  err_submit:
  	kfree_skb(skb);
  err_skb:
  	usb_free_urb(urb);
  err_urb:
  	ath9k_hif_usb_dealloc_reg_in_urbs(hif_dev);
  	return ret;
  }
  
  static int ath9k_hif_usb_alloc_urbs(struct hif_device_usb *hif_dev)
  {
  	/* Register Write */
  	init_usb_anchor(&hif_dev->regout_submitted);
  
  	/* TX */
  	if (ath9k_hif_usb_alloc_tx_urbs(hif_dev) < 0)
  		goto err;
  
  	/* RX */
  	if (ath9k_hif_usb_alloc_rx_urbs(hif_dev) < 0)
  		goto err_rx;
  
  	/* Register Read */
  	if (ath9k_hif_usb_alloc_reg_in_urbs(hif_dev) < 0)
  		goto err_reg;
  
  	return 0;
  err_reg:
  	ath9k_hif_usb_dealloc_rx_urbs(hif_dev);
  err_rx:
  	ath9k_hif_usb_dealloc_tx_urbs(hif_dev);
  err:
  	return -ENOMEM;
  }
  
  static void ath9k_hif_usb_dealloc_urbs(struct hif_device_usb *hif_dev)
  {
  	usb_kill_anchored_urbs(&hif_dev->regout_submitted);
  	ath9k_hif_usb_dealloc_reg_in_urbs(hif_dev);
  	ath9k_hif_usb_dealloc_tx_urbs(hif_dev);
  	ath9k_hif_usb_dealloc_rx_urbs(hif_dev);
  }
  
  static int ath9k_hif_usb_download_fw(struct hif_device_usb *hif_dev)
  {
  	int transfer, err;
  	const void *data = hif_dev->fw_data;
  	size_t len = hif_dev->fw_size;
  	u32 addr = AR9271_FIRMWARE;
  	u8 *buf = kzalloc(4096, GFP_KERNEL);
  	u32 firm_offset;
  
  	if (!buf)
  		return -ENOMEM;
  
  	while (len) {
  		transfer = min_t(size_t, len, 4096);
  		memcpy(buf, data, transfer);
  
  		err = usb_control_msg(hif_dev->udev,
  				      usb_sndctrlpipe(hif_dev->udev, 0),
  				      FIRMWARE_DOWNLOAD, 0x40 | USB_DIR_OUT,
  				      addr >> 8, 0, buf, transfer, HZ);
  		if (err < 0) {
  			kfree(buf);
  			return err;
  		}
  
  		len -= transfer;
  		data += transfer;
  		addr += transfer;
  	}
  	kfree(buf);
  
  	if (IS_AR7010_DEVICE(hif_dev->usb_device_id->driver_info))
  		firm_offset = AR7010_FIRMWARE_TEXT;
  	else
  		firm_offset = AR9271_FIRMWARE_TEXT;
  
  	/*
  	 * Issue FW download complete command to firmware.
  	 */
  	err = usb_control_msg(hif_dev->udev, usb_sndctrlpipe(hif_dev->udev, 0),
  			      FIRMWARE_DOWNLOAD_COMP,
  			      0x40 | USB_DIR_OUT,
  			      firm_offset >> 8, 0, NULL, 0, HZ);
  	if (err)
  		return -EIO;
  
  	dev_info(&hif_dev->udev->dev, "ath9k_htc: Transferred FW: %s, size: %ld
  ",
  		 hif_dev->fw_name, (unsigned long) hif_dev->fw_size);
  
  	return 0;
  }
  
  static int ath9k_hif_usb_dev_init(struct hif_device_usb *hif_dev)
  {
  	int ret;
  
  	ret = ath9k_hif_usb_download_fw(hif_dev);
  	if (ret) {
  		dev_err(&hif_dev->udev->dev,
  			"ath9k_htc: Firmware - %s download failed
  ",
  			hif_dev->fw_name);
  		return ret;
  	}
  
  	/* Alloc URBs */
  	ret = ath9k_hif_usb_alloc_urbs(hif_dev);
  	if (ret) {
  		dev_err(&hif_dev->udev->dev,
  			"ath9k_htc: Unable to allocate URBs
  ");
  		return ret;
  	}
  
  	return 0;
  }
  
  static void ath9k_hif_usb_dev_deinit(struct hif_device_usb *hif_dev)
  {
  	ath9k_hif_usb_dealloc_urbs(hif_dev);
  }
  
  /*
   * If initialization fails or the FW cannot be retrieved,
   * detach the device.
   */
  static void ath9k_hif_usb_firmware_fail(struct hif_device_usb *hif_dev)
  {
  	struct device *dev = &hif_dev->udev->dev;
  	struct device *parent = dev->parent;
  
  	complete_all(&hif_dev->fw_done);
  
  	if (parent)
  		device_lock(parent);
  
  	device_release_driver(dev);
  
  	if (parent)
  		device_unlock(parent);
  }
  
  static void ath9k_hif_usb_firmware_cb(const struct firmware *fw, void *context);
  
  /* taken from iwlwifi */
  static int ath9k_hif_request_firmware(struct hif_device_usb *hif_dev,
  				      bool first)
  {
  	char index[8], *chip;
  	int ret;
  
  	if (first) {
  		if (htc_use_dev_fw) {
  			hif_dev->fw_minor_index = FIRMWARE_MINOR_IDX_MAX + 1;
  			sprintf(index, "%s", "dev");
  		} else {
  			hif_dev->fw_minor_index = FIRMWARE_MINOR_IDX_MAX;
  			sprintf(index, "%d", hif_dev->fw_minor_index);
  		}
  	} else {
  		hif_dev->fw_minor_index--;
  		sprintf(index, "%d", hif_dev->fw_minor_index);
  	}
  
  	/* test for FW 1.3 */
  	if (MAJOR_VERSION_REQ == 1 && hif_dev->fw_minor_index == 3) {
  		const char *filename;
  
  		if (IS_AR7010_DEVICE(hif_dev->usb_device_id->driver_info))
  			filename = FIRMWARE_AR7010_1_1;
  		else
  			filename = FIRMWARE_AR9271;
  
  		/* expected fw locations:
  		 * - htc_9271.fw   (stable version 1.3, depricated)
  		 */
  		snprintf(hif_dev->fw_name, sizeof(hif_dev->fw_name),
  			 "%s", filename);
  
  	} else if (hif_dev->fw_minor_index < FIRMWARE_MINOR_IDX_MIN) {
  		dev_err(&hif_dev->udev->dev, "no suitable firmware found!
  ");
  
  		return -ENOENT;
  	} else {
  		if (IS_AR7010_DEVICE(hif_dev->usb_device_id->driver_info))
  			chip = "7010";
  		else
  			chip = "9271";
  
  		/* expected fw locations:
  		 * - ath9k_htc/htc_9271-1.dev.0.fw (development version)
  		 * - ath9k_htc/htc_9271-1.4.0.fw   (stable version)
  		 */
  		snprintf(hif_dev->fw_name, sizeof(hif_dev->fw_name),
  			 "%s/htc_%s-%d.%s.0.fw", HTC_FW_PATH,
  			 chip, MAJOR_VERSION_REQ, index);
  	}
  
  	ret = request_firmware_nowait(THIS_MODULE, true, hif_dev->fw_name,
  				      &hif_dev->udev->dev, GFP_KERNEL,
  				      hif_dev, ath9k_hif_usb_firmware_cb);
  	if (ret) {
  		dev_err(&hif_dev->udev->dev,
  			"ath9k_htc: Async request for firmware %s failed
  ",
  			hif_dev->fw_name);
  		return ret;
  	}
  
  	dev_info(&hif_dev->udev->dev, "ath9k_htc: Firmware %s requested
  ",
  		 hif_dev->fw_name);
  
  	return ret;
  }
  
  static void ath9k_hif_usb_firmware_cb(const struct firmware *fw, void *context)
  {
  	struct hif_device_usb *hif_dev = context;
  	int ret;
  
  	if (!fw) {
  		ret = ath9k_hif_request_firmware(hif_dev, false);
  		if (!ret)
  			return;
  
  		dev_err(&hif_dev->udev->dev,
  			"ath9k_htc: Failed to get firmware %s
  ",
  			hif_dev->fw_name);
  		goto err_fw;
  	}
  
  	hif_dev->htc_handle = ath9k_htc_hw_alloc(hif_dev, &hif_usb,
  						 &hif_dev->udev->dev);
  	if (hif_dev->htc_handle == NULL)
  		goto err_dev_alloc;
  
  	hif_dev->fw_data = fw->data;
  	hif_dev->fw_size = fw->size;
  
  	/* Proceed with initialization */
  
  	ret = ath9k_hif_usb_dev_init(hif_dev);
  	if (ret)
  		goto err_dev_init;
  
  	ret = ath9k_htc_hw_init(hif_dev->htc_handle,
  				&hif_dev->interface->dev,
  				hif_dev->usb_device_id->idProduct,
  				hif_dev->udev->product,
  				hif_dev->usb_device_id->driver_info);
  	if (ret) {
  		ret = -EINVAL;
  		goto err_htc_hw_init;
  	}
  
  	release_firmware(fw);
  	hif_dev->flags |= HIF_USB_READY;
  	complete_all(&hif_dev->fw_done);
  
  	return;
  
  err_htc_hw_init:
  	ath9k_hif_usb_dev_deinit(hif_dev);
  err_dev_init:
  	ath9k_htc_hw_free(hif_dev->htc_handle);
  err_dev_alloc:
  	release_firmware(fw);
  err_fw:
  	ath9k_hif_usb_firmware_fail(hif_dev);
  }
  
  /*
   * An exact copy of the function from zd1211rw.
   */
  static int send_eject_command(struct usb_interface *interface)
  {
  	struct usb_device *udev = interface_to_usbdev(interface);
  	struct usb_host_interface *iface_desc = &interface->altsetting[0];
  	struct usb_endpoint_descriptor *endpoint;
  	unsigned char *cmd;
  	u8 bulk_out_ep;
  	int r;
  
  	/* Find bulk out endpoint */
  	for (r = 1; r >= 0; r--) {
  		endpoint = &iface_desc->endpoint[r].desc;
  		if (usb_endpoint_dir_out(endpoint) &&
  		    usb_endpoint_xfer_bulk(endpoint)) {
  			bulk_out_ep = endpoint->bEndpointAddress;
  			break;
  		}
  	}
  	if (r == -1) {
  		dev_err(&udev->dev,
  			"ath9k_htc: Could not find bulk out endpoint
  ");
  		return -ENODEV;
  	}
  
  	cmd = kzalloc(31, GFP_KERNEL);
  	if (cmd == NULL)
  		return -ENODEV;
  
  	/* USB bulk command block */
  	cmd[0] = 0x55;	/* bulk command signature */
  	cmd[1] = 0x53;	/* bulk command signature */
  	cmd[2] = 0x42;	/* bulk command signature */
  	cmd[3] = 0x43;	/* bulk command signature */
  	cmd[14] = 6;	/* command length */
  
  	cmd[15] = 0x1b;	/* SCSI command: START STOP UNIT */
  	cmd[19] = 0x2;	/* eject disc */
  
  	dev_info(&udev->dev, "Ejecting storage device...
  ");
  	r = usb_bulk_msg(udev, usb_sndbulkpipe(udev, bulk_out_ep),
  		cmd, 31, NULL, 2000);
  	kfree(cmd);
  	if (r)
  		return r;
  
  	/* At this point, the device disconnects and reconnects with the real
  	 * ID numbers. */
  
  	usb_set_intfdata(interface, NULL);
  	return 0;
  }
  
  static int ath9k_hif_usb_probe(struct usb_interface *interface,
  			       const struct usb_device_id *id)
  {
  	struct usb_device *udev = interface_to_usbdev(interface);
  	struct hif_device_usb *hif_dev;
  	int ret = 0;
  
  	if (id->driver_info == STORAGE_DEVICE)
  		return send_eject_command(interface);
  
  	hif_dev = kzalloc(sizeof(struct hif_device_usb), GFP_KERNEL);
  	if (!hif_dev) {
  		ret = -ENOMEM;
  		goto err_alloc;
  	}
  
  	usb_get_dev(udev);
  
  	hif_dev->udev = udev;
  	hif_dev->interface = interface;
  	hif_dev->usb_device_id = id;
  #ifdef CONFIG_PM
  	udev->reset_resume = 1;
  #endif
  	usb_set_intfdata(interface, hif_dev);
  
  	init_completion(&hif_dev->fw_done);
  
  	ret = ath9k_hif_request_firmware(hif_dev, true);
  	if (ret)
  		goto err_fw_req;
  
  	return ret;
  
  err_fw_req:
  	usb_set_intfdata(interface, NULL);
  	kfree(hif_dev);
  	usb_put_dev(udev);
  err_alloc:
  	return ret;
  }
  
  static void ath9k_hif_usb_reboot(struct usb_device *udev)
  {
  	u32 reboot_cmd = 0xffffffff;
  	void *buf;
  	int ret;
  
  	buf = kmemdup(&reboot_cmd, 4, GFP_KERNEL);
  	if (!buf)
  		return;
  
  	ret = usb_interrupt_msg(udev, usb_sndintpipe(udev, USB_REG_OUT_PIPE),
  			   buf, 4, NULL, HZ);
  	if (ret)
  		dev_err(&udev->dev, "ath9k_htc: USB reboot failed
  ");
  
  	kfree(buf);
  }
  
  static void ath9k_hif_usb_disconnect(struct usb_interface *interface)
  {
  	struct usb_device *udev = interface_to_usbdev(interface);
  	struct hif_device_usb *hif_dev = usb_get_intfdata(interface);
  	bool unplugged = (udev->state == USB_STATE_NOTATTACHED) ? true : false;
  
  	if (!hif_dev)
  		return;
  
  	wait_for_completion(&hif_dev->fw_done);
  
  	if (hif_dev->flags & HIF_USB_READY) {
  		ath9k_htc_hw_deinit(hif_dev->htc_handle, unplugged);
  		ath9k_htc_hw_free(hif_dev->htc_handle);
  		ath9k_hif_usb_dev_deinit(hif_dev);
  	}
  
  	usb_set_intfdata(interface, NULL);
  
  	/* If firmware was loaded we should drop it
  	 * go back to first stage bootloader. */
  	if (!unplugged && (hif_dev->flags & HIF_USB_READY))
  		ath9k_hif_usb_reboot(udev);
  
  	kfree(hif_dev);
  	dev_info(&udev->dev, "ath9k_htc: USB layer deinitialized
  ");
  	usb_put_dev(udev);
  }
  
  #ifdef CONFIG_PM
  static int ath9k_hif_usb_suspend(struct usb_interface *interface,
  				 pm_message_t message)
  {
  	struct hif_device_usb *hif_dev = usb_get_intfdata(interface);
  
  	/*
  	 * The device has to be set to FULLSLEEP mode in case no
  	 * interface is up.
  	 */
  	if (!(hif_dev->flags & HIF_USB_START))
  		ath9k_htc_suspend(hif_dev->htc_handle);
  
  	wait_for_completion(&hif_dev->fw_done);
  
  	if (hif_dev->flags & HIF_USB_READY)
  		ath9k_hif_usb_dealloc_urbs(hif_dev);
  
  	return 0;
  }
  
  static int ath9k_hif_usb_resume(struct usb_interface *interface)
  {
  	struct hif_device_usb *hif_dev = usb_get_intfdata(interface);
  	struct htc_target *htc_handle = hif_dev->htc_handle;
  	int ret;
  	const struct firmware *fw;
  
  	ret = ath9k_hif_usb_alloc_urbs(hif_dev);
  	if (ret)
  		return ret;
  
  	if (hif_dev->flags & HIF_USB_READY) {
  		/* request cached firmware during suspend/resume cycle */
  		ret = request_firmware(&fw, hif_dev->fw_name,
  				       &hif_dev->udev->dev);
  		if (ret)
  			goto fail_resume;
  
  		hif_dev->fw_data = fw->data;
  		hif_dev->fw_size = fw->size;
  		ret = ath9k_hif_usb_download_fw(hif_dev);
  		release_firmware(fw);
  		if (ret)
  			goto fail_resume;
  	} else {
  		ath9k_hif_usb_dealloc_urbs(hif_dev);
  		return -EIO;
  	}
  
  	mdelay(100);
  
  	ret = ath9k_htc_resume(htc_handle);
  
  	if (ret)
  		goto fail_resume;
  
  	return 0;
  
  fail_resume:
  	ath9k_hif_usb_dealloc_urbs(hif_dev);
  
  	return ret;
  }
  #endif
  
  static struct usb_driver ath9k_hif_usb_driver = {
  	.name = KBUILD_MODNAME,
  	.probe = ath9k_hif_usb_probe,
  	.disconnect = ath9k_hif_usb_disconnect,
  #ifdef CONFIG_PM
  	.suspend = ath9k_hif_usb_suspend,
  	.resume = ath9k_hif_usb_resume,
  	.reset_resume = ath9k_hif_usb_resume,
  #endif
  	.id_table = ath9k_hif_usb_ids,
  	.soft_unbind = 1,
  	.disable_hub_initiated_lpm = 1,
  };
  
  int ath9k_hif_usb_init(void)
  {
  	return usb_register(&ath9k_hif_usb_driver);
  }
  
  void ath9k_hif_usb_exit(void)
  {
  	usb_deregister(&ath9k_hif_usb_driver);
  }