/******************************************************************************
   *
   * Copyright(c) 2009-2012  Realtek Corporation. All rights reserved.
   *
   * This program is free software; you can redistribute it and/or modify it
   * under the terms of version 2 of the GNU General Public License as
   * published by the Free Software Foundation.
   *
   * This program is distributed in the hope that it will be useful, but WITHOUT
   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
   * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
   * more details.
   *
   * You should have received a copy of the GNU General Public License along with
   * this program; if not, write to the Free Software Foundation, Inc.,
   * 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA
   *
   * The full GNU General Public License is included in this distribution in the
   * file called LICENSE.
   *
   * Contact Information:
   * wlanfae <wlanfae@realtek.com>
   * Realtek Corporation, No. 2, Innovation Road II, Hsinchu Science Park,
   * Hsinchu 300, Taiwan.
   *
   *****************************************************************************/
  
  #include "wifi.h"
  #include "core.h"
  #include "usb.h"
  #include "base.h"
  #include "ps.h"
  #include "rtl8192c/fw_common.h"
  #include <linux/export.h>
  #include <linux/module.h>
  
  MODULE_AUTHOR("lizhaoming	<chaoming_li@realsil.com.cn>");
  MODULE_AUTHOR("Realtek WlanFAE	<wlanfae@realtek.com>");
  MODULE_AUTHOR("Larry Finger	<Larry.FInger@lwfinger.net>");
  MODULE_LICENSE("GPL");
  MODULE_DESCRIPTION("USB basic driver for rtlwifi");
  
  #define	REALTEK_USB_VENQT_READ			0xC0
  #define	REALTEK_USB_VENQT_WRITE			0x40
  #define REALTEK_USB_VENQT_CMD_REQ		0x05
  #define	REALTEK_USB_VENQT_CMD_IDX		0x00
  
  #define MAX_USBCTRL_VENDORREQ_TIMES		10
  
  static void usbctrl_async_callback(struct urb *urb)
  {
  	if (urb) {
  		/* free dr */
  		kfree(urb->setup_packet);
  		/* free databuf */
  		kfree(urb->transfer_buffer);
  	}
  }
  
  static int _usbctrl_vendorreq_async_write(struct usb_device *udev, u8 request,
  					  u16 value, u16 index, void *pdata,
  					  u16 len)
  {
  	int rc;
  	unsigned int pipe;
  	u8 reqtype;
  	struct usb_ctrlrequest *dr;
  	struct urb *urb;
  	const u16 databuf_maxlen = REALTEK_USB_VENQT_MAX_BUF_SIZE;
  	u8 *databuf;
  
  	if (WARN_ON_ONCE(len > databuf_maxlen))
  		len = databuf_maxlen;
  
  	pipe = usb_sndctrlpipe(udev, 0); /* write_out */
  	reqtype =  REALTEK_USB_VENQT_WRITE;
  
  	dr = kzalloc(sizeof(*dr), GFP_ATOMIC);
  	if (!dr)
  		return -ENOMEM;
  
  	databuf = kzalloc(databuf_maxlen, GFP_ATOMIC);
  	if (!databuf) {
  		kfree(dr);
  		return -ENOMEM;
  	}
  
  	urb = usb_alloc_urb(0, GFP_ATOMIC);
  	if (!urb) {
  		kfree(databuf);
  		kfree(dr);
  		return -ENOMEM;
  	}
  
  	dr->bRequestType = reqtype;
  	dr->bRequest = request;
  	dr->wValue = cpu_to_le16(value);
  	dr->wIndex = cpu_to_le16(index);
  	dr->wLength = cpu_to_le16(len);
  	/* data are already in little-endian order */
  	memcpy(databuf, pdata, len);
  	usb_fill_control_urb(urb, udev, pipe,
  			     (unsigned char *)dr, databuf, len,
  			     usbctrl_async_callback, NULL);
  	rc = usb_submit_urb(urb, GFP_ATOMIC);
  	if (rc < 0) {
  		kfree(databuf);
  		kfree(dr);
  	}
  	usb_free_urb(urb);
  	return rc;
  }
  
  static int _usbctrl_vendorreq_sync_read(struct usb_device *udev, u8 request,
  					u16 value, u16 index, void *pdata,
  					u16 len)
  {
  	unsigned int pipe;
  	int status;
  	u8 reqtype;
  	int vendorreq_times = 0;
  	static int count;
  
  	pipe = usb_rcvctrlpipe(udev, 0); /* read_in */
  	reqtype =  REALTEK_USB_VENQT_READ;
  
  	do {
  		status = usb_control_msg(udev, pipe, request, reqtype, value,
  					 index, pdata, len, 1000);
  		if (status < 0) {
  			/* firmware download is checksumed, don't retry */
  			if ((value >= FW_8192C_START_ADDRESS &&
  			    value <= FW_8192C_END_ADDRESS))
  				break;
  		} else {
  			break;
  		}
  	} while (++vendorreq_times < MAX_USBCTRL_VENDORREQ_TIMES);
  
  	if (status < 0 && count++ < 4)
  		pr_err("reg 0x%x, usbctrl_vendorreq TimeOut! status:0x%x value=0x%x
  ",
  		       value, status, *(u32 *)pdata);
  	return status;
  }
  
  static u32 _usb_read_sync(struct rtl_priv *rtlpriv, u32 addr, u16 len)
  {
  	struct device *dev = rtlpriv->io.dev;
  	struct usb_device *udev = to_usb_device(dev);
  	u8 request;
  	u16 wvalue;
  	u16 index;
  	__le32 *data;
  	unsigned long flags;
  
  	spin_lock_irqsave(&rtlpriv->locks.usb_lock, flags);
  	if (++rtlpriv->usb_data_index >= RTL_USB_MAX_RX_COUNT)
  		rtlpriv->usb_data_index = 0;
  	data = &rtlpriv->usb_data[rtlpriv->usb_data_index];
  	spin_unlock_irqrestore(&rtlpriv->locks.usb_lock, flags);
  	request = REALTEK_USB_VENQT_CMD_REQ;
  	index = REALTEK_USB_VENQT_CMD_IDX; /* n/a */
  
  	wvalue = (u16)addr;
  	_usbctrl_vendorreq_sync_read(udev, request, wvalue, index, data, len);
  	return le32_to_cpu(*data);
  }
  
  static u8 _usb_read8_sync(struct rtl_priv *rtlpriv, u32 addr)
  {
  	return (u8)_usb_read_sync(rtlpriv, addr, 1);
  }
  
  static u16 _usb_read16_sync(struct rtl_priv *rtlpriv, u32 addr)
  {
  	return (u16)_usb_read_sync(rtlpriv, addr, 2);
  }
  
  static u32 _usb_read32_sync(struct rtl_priv *rtlpriv, u32 addr)
  {
  	return _usb_read_sync(rtlpriv, addr, 4);
  }
  
  static void _usb_write_async(struct usb_device *udev, u32 addr, u32 val,
  			     u16 len)
  {
  	u8 request;
  	u16 wvalue;
  	u16 index;
  	__le32 data;
  
  	request = REALTEK_USB_VENQT_CMD_REQ;
  	index = REALTEK_USB_VENQT_CMD_IDX; /* n/a */
  	wvalue = (u16)(addr&0x0000ffff);
  	data = cpu_to_le32(val);
  	_usbctrl_vendorreq_async_write(udev, request, wvalue, index, &data,
  				       len);
  }
  
  static void _usb_write8_async(struct rtl_priv *rtlpriv, u32 addr, u8 val)
  {
  	struct device *dev = rtlpriv->io.dev;
  
  	_usb_write_async(to_usb_device(dev), addr, val, 1);
  }
  
  static void _usb_write16_async(struct rtl_priv *rtlpriv, u32 addr, u16 val)
  {
  	struct device *dev = rtlpriv->io.dev;
  
  	_usb_write_async(to_usb_device(dev), addr, val, 2);
  }
  
  static void _usb_write32_async(struct rtl_priv *rtlpriv, u32 addr, u32 val)
  {
  	struct device *dev = rtlpriv->io.dev;
  
  	_usb_write_async(to_usb_device(dev), addr, val, 4);
  }
  
  static void _usb_writeN_sync(struct rtl_priv *rtlpriv, u32 addr, void *data,
  			     u16 len)
  {
  	struct device *dev = rtlpriv->io.dev;
  	struct usb_device *udev = to_usb_device(dev);
  	u8 request = REALTEK_USB_VENQT_CMD_REQ;
  	u8 reqtype =  REALTEK_USB_VENQT_WRITE;
  	u16 wvalue;
  	u16 index = REALTEK_USB_VENQT_CMD_IDX;
  	int pipe = usb_sndctrlpipe(udev, 0); /* write_out */
  	u8 *buffer;
  
  	wvalue = (u16)(addr & 0x0000ffff);
  	buffer = kmemdup(data, len, GFP_ATOMIC);
  	if (!buffer)
  		return;
  	usb_control_msg(udev, pipe, request, reqtype, wvalue,
  			index, buffer, len, 50);
  
  	kfree(buffer);
  }
  
  static void _rtl_usb_io_handler_init(struct device *dev,
  				     struct ieee80211_hw *hw)
  {
  	struct rtl_priv *rtlpriv = rtl_priv(hw);
  
  	rtlpriv->io.dev = dev;
  	mutex_init(&rtlpriv->io.bb_mutex);
  	rtlpriv->io.write8_async	= _usb_write8_async;
  	rtlpriv->io.write16_async	= _usb_write16_async;
  	rtlpriv->io.write32_async	= _usb_write32_async;
  	rtlpriv->io.read8_sync		= _usb_read8_sync;
  	rtlpriv->io.read16_sync		= _usb_read16_sync;
  	rtlpriv->io.read32_sync		= _usb_read32_sync;
  	rtlpriv->io.writeN_sync		= _usb_writeN_sync;
  }
  
  static void _rtl_usb_io_handler_release(struct ieee80211_hw *hw)
  {
  	struct rtl_priv __maybe_unused *rtlpriv = rtl_priv(hw);
  
  	mutex_destroy(&rtlpriv->io.bb_mutex);
  }
  
  /**
   *
   *	Default aggregation handler. Do nothing and just return the oldest skb.
   */
  static struct sk_buff *_none_usb_tx_aggregate_hdl(struct ieee80211_hw *hw,
  						  struct sk_buff_head *list)
  {
  	return skb_dequeue(list);
  }
  
  #define IS_HIGH_SPEED_USB(udev) \
  		((USB_SPEED_HIGH == (udev)->speed) ? true : false)
  
  static int _rtl_usb_init_tx(struct ieee80211_hw *hw)
  {
  	u32 i;
  	struct rtl_priv *rtlpriv = rtl_priv(hw);
  	struct rtl_usb *rtlusb = rtl_usbdev(rtl_usbpriv(hw));
  
  	rtlusb->max_bulk_out_size = IS_HIGH_SPEED_USB(rtlusb->udev)
  						    ? USB_HIGH_SPEED_BULK_SIZE
  						    : USB_FULL_SPEED_BULK_SIZE;
  
  	RT_TRACE(rtlpriv, COMP_INIT, DBG_DMESG, "USB Max Bulk-out Size=%d
  ",
  		 rtlusb->max_bulk_out_size);
  
  	for (i = 0; i < __RTL_TXQ_NUM; i++) {
  		u32 ep_num = rtlusb->ep_map.ep_mapping[i];
  		if (!ep_num) {
  			RT_TRACE(rtlpriv, COMP_INIT, DBG_DMESG,
  				 "Invalid endpoint map setting!
  ");
  			return -EINVAL;
  		}
  	}
  
  	rtlusb->usb_tx_post_hdl =
  		 rtlpriv->cfg->usb_interface_cfg->usb_tx_post_hdl;
  	rtlusb->usb_tx_cleanup	=
  		 rtlpriv->cfg->usb_interface_cfg->usb_tx_cleanup;
  	rtlusb->usb_tx_aggregate_hdl =
  		 (rtlpriv->cfg->usb_interface_cfg->usb_tx_aggregate_hdl)
  		 ? rtlpriv->cfg->usb_interface_cfg->usb_tx_aggregate_hdl
  		 : &_none_usb_tx_aggregate_hdl;
  
  	init_usb_anchor(&rtlusb->tx_submitted);
  	for (i = 0; i < RTL_USB_MAX_EP_NUM; i++) {
  		skb_queue_head_init(&rtlusb->tx_skb_queue[i]);
  		init_usb_anchor(&rtlusb->tx_pending[i]);
  	}
  	return 0;
  }
  
  static void _rtl_rx_work(unsigned long param);
  
  static int _rtl_usb_init_rx(struct ieee80211_hw *hw)
  {
  	struct rtl_priv *rtlpriv = rtl_priv(hw);
  	struct rtl_usb_priv *usb_priv = rtl_usbpriv(hw);
  	struct rtl_usb *rtlusb = rtl_usbdev(usb_priv);
  
  	rtlusb->rx_max_size = rtlpriv->cfg->usb_interface_cfg->rx_max_size;
  	rtlusb->rx_urb_num = rtlpriv->cfg->usb_interface_cfg->rx_urb_num;
  	rtlusb->in_ep = rtlpriv->cfg->usb_interface_cfg->in_ep_num;
  	rtlusb->usb_rx_hdl = rtlpriv->cfg->usb_interface_cfg->usb_rx_hdl;
  	rtlusb->usb_rx_segregate_hdl =
  		rtlpriv->cfg->usb_interface_cfg->usb_rx_segregate_hdl;
  
  	pr_info("rx_max_size %d, rx_urb_num %d, in_ep %d
  ",
  		rtlusb->rx_max_size, rtlusb->rx_urb_num, rtlusb->in_ep);
  	init_usb_anchor(&rtlusb->rx_submitted);
  	init_usb_anchor(&rtlusb->rx_cleanup_urbs);
  
  	skb_queue_head_init(&rtlusb->rx_queue);
  	rtlusb->rx_work_tasklet.func = _rtl_rx_work;
  	rtlusb->rx_work_tasklet.data = (unsigned long)rtlusb;
  
  	return 0;
  }
  
  static int _rtl_usb_init(struct ieee80211_hw *hw)
  {
  	struct rtl_priv *rtlpriv = rtl_priv(hw);
  	struct rtl_usb_priv *usb_priv = rtl_usbpriv(hw);
  	struct rtl_usb *rtlusb = rtl_usbdev(usb_priv);
  	int err;
  	u8 epidx;
  	struct usb_interface	*usb_intf = rtlusb->intf;
  	u8 epnums = usb_intf->cur_altsetting->desc.bNumEndpoints;
  
  	rtlusb->out_ep_nums = rtlusb->in_ep_nums = 0;
  	for (epidx = 0; epidx < epnums; epidx++) {
  		struct usb_endpoint_descriptor *pep_desc;
  		pep_desc = &usb_intf->cur_altsetting->endpoint[epidx].desc;
  
  		if (usb_endpoint_dir_in(pep_desc))
  			rtlusb->in_ep_nums++;
  		else if (usb_endpoint_dir_out(pep_desc))
  			rtlusb->out_ep_nums++;
  
  		RT_TRACE(rtlpriv, COMP_INIT, DBG_DMESG,
  			 "USB EP(0x%02x), MaxPacketSize=%d, Interval=%d
  ",
  			 pep_desc->bEndpointAddress, pep_desc->wMaxPacketSize,
  			 pep_desc->bInterval);
  	}
  	if (rtlusb->in_ep_nums <  rtlpriv->cfg->usb_interface_cfg->in_ep_num) {
  		pr_err("Too few input end points found
  ");
  		return -EINVAL;
  	}
  	if (rtlusb->out_ep_nums == 0) {
  		pr_err("No output end points found
  ");
  		return -EINVAL;
  	}
  	/* usb endpoint mapping */
  	err = rtlpriv->cfg->usb_interface_cfg->usb_endpoint_mapping(hw);
  	rtlusb->usb_mq_to_hwq =  rtlpriv->cfg->usb_interface_cfg->usb_mq_to_hwq;
  	_rtl_usb_init_tx(hw);
  	_rtl_usb_init_rx(hw);
  	return err;
  }
  
  static void rtl_usb_init_sw(struct ieee80211_hw *hw)
  {
  	struct rtl_mac *mac = rtl_mac(rtl_priv(hw));
  	struct rtl_hal *rtlhal = rtl_hal(rtl_priv(hw));
  	struct rtl_ps_ctl *ppsc = rtl_psc(rtl_priv(hw));
  	struct rtl_usb *rtlusb = rtl_usbdev(rtl_usbpriv(hw));
  
  	rtlhal->hw = hw;
  	ppsc->inactiveps = false;
  	ppsc->leisure_ps = false;
  	ppsc->fwctrl_lps = false;
  	ppsc->reg_fwctrl_lps = 3;
  	ppsc->reg_max_lps_awakeintvl = 5;
  	ppsc->fwctrl_psmode = FW_PS_DTIM_MODE;
  
  	 /* IBSS */
  	mac->beacon_interval = 100;
  
  	 /* AMPDU */
  	mac->min_space_cfg = 0;
  	mac->max_mss_density = 0;
  
  	/* set sane AMPDU defaults */
  	mac->current_ampdu_density = 7;
  	mac->current_ampdu_factor = 3;
  
  	/* QOS */
  	rtlusb->acm_method = EACMWAY2_SW;
  
  	/* IRQ */
  	/* HIMR - turn all on */
  	rtlusb->irq_mask[0] = 0xFFFFFFFF;
  	/* HIMR_EX - turn all on */
  	rtlusb->irq_mask[1] = 0xFFFFFFFF;
  	rtlusb->disableHWSM =  true;
  }
  
  static void _rtl_rx_completed(struct urb *urb);
  
  static int _rtl_prep_rx_urb(struct ieee80211_hw *hw, struct rtl_usb *rtlusb,
  			      struct urb *urb, gfp_t gfp_mask)
  {
  	struct rtl_priv *rtlpriv = rtl_priv(hw);
  	void *buf;
  
  	buf = usb_alloc_coherent(rtlusb->udev, rtlusb->rx_max_size, gfp_mask,
  				 &urb->transfer_dma);
  	if (!buf) {
  		RT_TRACE(rtlpriv, COMP_USB, DBG_EMERG,
  			 "Failed to usb_alloc_coherent!!
  ");
  		return -ENOMEM;
  	}
  
  	usb_fill_bulk_urb(urb, rtlusb->udev,
  			  usb_rcvbulkpipe(rtlusb->udev, rtlusb->in_ep),
  			  buf, rtlusb->rx_max_size, _rtl_rx_completed, rtlusb);
  	urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
  
  	return 0;
  }
  
  static void _rtl_usb_rx_process_agg(struct ieee80211_hw *hw,
  				    struct sk_buff *skb)
  {
  	struct rtl_priv *rtlpriv = rtl_priv(hw);
  	u8 *rxdesc = skb->data;
  	struct ieee80211_hdr *hdr;
  	bool unicast = false;
  	__le16 fc;
  	struct ieee80211_rx_status rx_status = {0};
  	struct rtl_stats stats = {
  		.signal = 0,
  		.rate = 0,
  	};
  
  	skb_pull(skb, RTL_RX_DESC_SIZE);
  	rtlpriv->cfg->ops->query_rx_desc(hw, &stats, &rx_status, rxdesc, skb);
  	skb_pull(skb, (stats.rx_drvinfo_size + stats.rx_bufshift));
  	hdr = (struct ieee80211_hdr *)(skb->data);
  	fc = hdr->frame_control;
  	if (!stats.crc) {
  		memcpy(IEEE80211_SKB_RXCB(skb), &rx_status, sizeof(rx_status));
  
  		if (is_broadcast_ether_addr(hdr->addr1)) {
  			/*TODO*/;
  		} else if (is_multicast_ether_addr(hdr->addr1)) {
  			/*TODO*/
  		} else {
  			unicast = true;
  			rtlpriv->stats.rxbytesunicast +=  skb->len;
  		}
  
  		if (ieee80211_is_data(fc)) {
  			rtlpriv->cfg->ops->led_control(hw, LED_CTL_RX);
  
  			if (unicast)
  				rtlpriv->link_info.num_rx_inperiod++;
  		}
  		/* static bcn for roaming */
  		rtl_beacon_statistic(hw, skb);
  	}
  }
  
  static void _rtl_usb_rx_process_noagg(struct ieee80211_hw *hw,
  				      struct sk_buff *skb)
  {
  	struct rtl_priv *rtlpriv = rtl_priv(hw);
  	u8 *rxdesc = skb->data;
  	struct ieee80211_hdr *hdr;
  	bool unicast = false;
  	__le16 fc;
  	struct ieee80211_rx_status rx_status = {0};
  	struct rtl_stats stats = {
  		.signal = 0,
  		.rate = 0,
  	};
  
  	skb_pull(skb, RTL_RX_DESC_SIZE);
  	rtlpriv->cfg->ops->query_rx_desc(hw, &stats, &rx_status, rxdesc, skb);
  	skb_pull(skb, (stats.rx_drvinfo_size + stats.rx_bufshift));
  	hdr = (struct ieee80211_hdr *)(skb->data);
  	fc = hdr->frame_control;
  	if (!stats.crc) {
  		memcpy(IEEE80211_SKB_RXCB(skb), &rx_status, sizeof(rx_status));
  
  		if (is_broadcast_ether_addr(hdr->addr1)) {
  			/*TODO*/;
  		} else if (is_multicast_ether_addr(hdr->addr1)) {
  			/*TODO*/
  		} else {
  			unicast = true;
  			rtlpriv->stats.rxbytesunicast +=  skb->len;
  		}
  
  		if (ieee80211_is_data(fc)) {
  			rtlpriv->cfg->ops->led_control(hw, LED_CTL_RX);
  
  			if (unicast)
  				rtlpriv->link_info.num_rx_inperiod++;
  		}
  
  		/* static bcn for roaming */
  		rtl_beacon_statistic(hw, skb);
  
  		if (likely(rtl_action_proc(hw, skb, false)))
  			ieee80211_rx(hw, skb);
  		else
  			dev_kfree_skb_any(skb);
  	} else {
  		dev_kfree_skb_any(skb);
  	}
  }
  
  static void _rtl_rx_pre_process(struct ieee80211_hw *hw, struct sk_buff *skb)
  {
  	struct sk_buff *_skb;
  	struct sk_buff_head rx_queue;
  	struct rtl_usb *rtlusb = rtl_usbdev(rtl_usbpriv(hw));
  
  	skb_queue_head_init(&rx_queue);
  	if (rtlusb->usb_rx_segregate_hdl)
  		rtlusb->usb_rx_segregate_hdl(hw, skb, &rx_queue);
  	WARN_ON(skb_queue_empty(&rx_queue));
  	while (!skb_queue_empty(&rx_queue)) {
  		_skb = skb_dequeue(&rx_queue);
  		_rtl_usb_rx_process_agg(hw, _skb);
  		ieee80211_rx(hw, _skb);
  	}
  }
  
  #define __RX_SKB_MAX_QUEUED	64
  
  static void _rtl_rx_work(unsigned long param)
  {
  	struct rtl_usb *rtlusb = (struct rtl_usb *)param;
  	struct ieee80211_hw *hw = usb_get_intfdata(rtlusb->intf);
  	struct sk_buff *skb;
  
  	while ((skb = skb_dequeue(&rtlusb->rx_queue))) {
  		if (unlikely(IS_USB_STOP(rtlusb))) {
  			dev_kfree_skb_any(skb);
  			continue;
  		}
  
  		if (likely(!rtlusb->usb_rx_segregate_hdl)) {
  			_rtl_usb_rx_process_noagg(hw, skb);
  		} else {
  			/* TO DO */
  			_rtl_rx_pre_process(hw, skb);
  			pr_err("rx agg not supported
  ");
  		}
  	}
  }
  
  static unsigned int _rtl_rx_get_padding(struct ieee80211_hdr *hdr,
  					unsigned int len)
  {
  #if NET_IP_ALIGN != 0
  	unsigned int padding = 0;
  #endif
  
  	/* make function no-op when possible */
  	if (NET_IP_ALIGN == 0 || len < sizeof(*hdr))
  		return 0;
  
  #if NET_IP_ALIGN != 0
  	/* alignment calculation as in lbtf_rx() / carl9170_rx_copy_data() */
  	/* TODO: deduplicate common code, define helper function instead? */
  
  	if (ieee80211_is_data_qos(hdr->frame_control)) {
  		u8 *qc = ieee80211_get_qos_ctl(hdr);
  
  		padding ^= NET_IP_ALIGN;
  
  		/* Input might be invalid, avoid accessing memory outside
  		 * the buffer.
  		 */
  		if ((unsigned long)qc - (unsigned long)hdr < len &&
  		    *qc & IEEE80211_QOS_CTL_A_MSDU_PRESENT)
  			padding ^= NET_IP_ALIGN;
  	}
  
  	if (ieee80211_has_a4(hdr->frame_control))
  		padding ^= NET_IP_ALIGN;
  
  	return padding;
  #endif
  }
  
  #define __RADIO_TAP_SIZE_RSV	32
  
  static void _rtl_rx_completed(struct urb *_urb)
  {
  	struct rtl_usb *rtlusb = (struct rtl_usb *)_urb->context;
  	struct ieee80211_hw *hw = usb_get_intfdata(rtlusb->intf);
  	struct rtl_priv *rtlpriv = rtl_priv(hw);
  	int err = 0;
  
  	if (unlikely(IS_USB_STOP(rtlusb)))
  		goto free;
  
  	if (likely(0 == _urb->status)) {
  		unsigned int padding;
  		struct sk_buff *skb;
  		unsigned int qlen;
  		unsigned int size = _urb->actual_length;
  		struct ieee80211_hdr *hdr;
  
  		if (size < RTL_RX_DESC_SIZE + sizeof(struct ieee80211_hdr)) {
  			RT_TRACE(rtlpriv, COMP_USB, DBG_EMERG,
  				 "Too short packet from bulk IN! (len: %d)
  ",
  				 size);
  			goto resubmit;
  		}
  
  		qlen = skb_queue_len(&rtlusb->rx_queue);
  		if (qlen >= __RX_SKB_MAX_QUEUED) {
  			RT_TRACE(rtlpriv, COMP_USB, DBG_EMERG,
  				 "Pending RX skbuff queue full! (qlen: %d)
  ",
  				 qlen);
  			goto resubmit;
  		}
  
  		hdr = (void *)(_urb->transfer_buffer + RTL_RX_DESC_SIZE);
  		padding = _rtl_rx_get_padding(hdr, size - RTL_RX_DESC_SIZE);
  
  		skb = dev_alloc_skb(size + __RADIO_TAP_SIZE_RSV + padding);
  		if (!skb) {
  			RT_TRACE(rtlpriv, COMP_USB, DBG_EMERG,
  				 "Can't allocate skb for bulk IN!
  ");
  			goto resubmit;
  		}
  
  		_rtl_install_trx_info(rtlusb, skb, rtlusb->in_ep);
  
  		/* Make sure the payload data is 4 byte aligned. */
  		skb_reserve(skb, padding);
  
  		/* reserve some space for mac80211's radiotap */
  		skb_reserve(skb, __RADIO_TAP_SIZE_RSV);
  
  		memcpy(skb_put(skb, size), _urb->transfer_buffer, size);
  
  		skb_queue_tail(&rtlusb->rx_queue, skb);
  		tasklet_schedule(&rtlusb->rx_work_tasklet);
  
  		goto resubmit;
  	}
  
  	switch (_urb->status) {
  	/* disconnect */
  	case -ENOENT:
  	case -ECONNRESET:
  	case -ENODEV:
  	case -ESHUTDOWN:
  		goto free;
  	default:
  		break;
  	}
  
  resubmit:
  	usb_anchor_urb(_urb, &rtlusb->rx_submitted);
  	err = usb_submit_urb(_urb, GFP_ATOMIC);
  	if (unlikely(err)) {
  		usb_unanchor_urb(_urb);
  		goto free;
  	}
  	return;
  
  free:
  	/* On some architectures, usb_free_coherent must not be called from
  	 * hardirq context. Queue urb to cleanup list.
  	 */
  	usb_anchor_urb(_urb, &rtlusb->rx_cleanup_urbs);
  }
  
  #undef __RADIO_TAP_SIZE_RSV
  
  static void _rtl_usb_cleanup_rx(struct ieee80211_hw *hw)
  {
  	struct rtl_priv *rtlpriv = rtl_priv(hw);
  	struct rtl_usb *rtlusb = rtl_usbdev(rtl_usbpriv(hw));
  	struct urb *urb;
  
  	usb_kill_anchored_urbs(&rtlusb->rx_submitted);
  
  	tasklet_kill(&rtlusb->rx_work_tasklet);
  	cancel_work_sync(&rtlpriv->works.lps_change_work);
  
  	flush_workqueue(rtlpriv->works.rtl_wq);
  	destroy_workqueue(rtlpriv->works.rtl_wq);
  
  	skb_queue_purge(&rtlusb->rx_queue);
  
  	while ((urb = usb_get_from_anchor(&rtlusb->rx_cleanup_urbs))) {
  		usb_free_coherent(urb->dev, urb->transfer_buffer_length,
  				urb->transfer_buffer, urb->transfer_dma);
  		usb_free_urb(urb);
  	}
  }
  
  static int _rtl_usb_receive(struct ieee80211_hw *hw)
  {
  	struct urb *urb;
  	int err;
  	int i;
  	struct rtl_priv *rtlpriv = rtl_priv(hw);
  	struct rtl_usb *rtlusb = rtl_usbdev(rtl_usbpriv(hw));
  
  	WARN_ON(0 == rtlusb->rx_urb_num);
  	/* 1600 == 1514 + max WLAN header + rtk info */
  	WARN_ON(rtlusb->rx_max_size < 1600);
  
  	for (i = 0; i < rtlusb->rx_urb_num; i++) {
  		err = -ENOMEM;
  		urb = usb_alloc_urb(0, GFP_KERNEL);
  		if (!urb) {
  			RT_TRACE(rtlpriv, COMP_USB, DBG_EMERG,
  				 "Failed to alloc URB!!
  ");
  			goto err_out;
  		}
  
  		err = _rtl_prep_rx_urb(hw, rtlusb, urb, GFP_KERNEL);
  		if (err < 0) {
  			RT_TRACE(rtlpriv, COMP_USB, DBG_EMERG,
  				 "Failed to prep_rx_urb!!
  ");
  			usb_free_urb(urb);
  			goto err_out;
  		}
  
  		usb_anchor_urb(urb, &rtlusb->rx_submitted);
  		err = usb_submit_urb(urb, GFP_KERNEL);
  		if (err)
  			goto err_out;
  		usb_free_urb(urb);
  	}
  	return 0;
  
  err_out:
  	usb_kill_anchored_urbs(&rtlusb->rx_submitted);
  	_rtl_usb_cleanup_rx(hw);
  	return err;
  }
  
  static int rtl_usb_start(struct ieee80211_hw *hw)
  {
  	int err;
  	struct rtl_priv *rtlpriv = rtl_priv(hw);
  	struct rtl_hal *rtlhal = rtl_hal(rtl_priv(hw));
  	struct rtl_usb *rtlusb = rtl_usbdev(rtl_usbpriv(hw));
  
  	err = rtlpriv->cfg->ops->hw_init(hw);
  	if (!err) {
  		rtl_init_rx_config(hw);
  
  		/* Enable software */
  		SET_USB_START(rtlusb);
  		/* should after adapter start and interrupt enable. */
  		set_hal_start(rtlhal);
  
  		/* Start bulk IN */
  		err = _rtl_usb_receive(hw);
  	}
  
  	return err;
  }
  /**
   *
   *
   */
  
  /*=======================  tx =========================================*/
  static void rtl_usb_cleanup(struct ieee80211_hw *hw)
  {
  	u32 i;
  	struct sk_buff *_skb;
  	struct rtl_usb *rtlusb = rtl_usbdev(rtl_usbpriv(hw));
  	struct ieee80211_tx_info *txinfo;
  
  	/* clean up rx stuff. */
  	_rtl_usb_cleanup_rx(hw);
  
  	/* clean up tx stuff */
  	for (i = 0; i < RTL_USB_MAX_EP_NUM; i++) {
  		while ((_skb = skb_dequeue(&rtlusb->tx_skb_queue[i]))) {
  			rtlusb->usb_tx_cleanup(hw, _skb);
  			txinfo = IEEE80211_SKB_CB(_skb);
  			ieee80211_tx_info_clear_status(txinfo);
  			txinfo->flags |= IEEE80211_TX_STAT_ACK;
  			ieee80211_tx_status_irqsafe(hw, _skb);
  		}
  		usb_kill_anchored_urbs(&rtlusb->tx_pending[i]);
  	}
  	usb_kill_anchored_urbs(&rtlusb->tx_submitted);
  }
  
  /**
   *
   * We may add some struct into struct rtl_usb later. Do deinit here.
   *
   */
  static void rtl_usb_deinit(struct ieee80211_hw *hw)
  {
  	rtl_usb_cleanup(hw);
  }
  
  static void rtl_usb_stop(struct ieee80211_hw *hw)
  {
  	struct rtl_priv *rtlpriv = rtl_priv(hw);
  	struct rtl_hal *rtlhal = rtl_hal(rtl_priv(hw));
  	struct rtl_usb *rtlusb = rtl_usbdev(rtl_usbpriv(hw));
  
  	/* should after adapter start and interrupt enable. */
  	set_hal_stop(rtlhal);
  	cancel_work_sync(&rtlpriv->works.fill_h2c_cmd);
  	/* Enable software */
  	SET_USB_STOP(rtlusb);
  	rtlpriv->cfg->ops->hw_disable(hw);
  }
  
  static void _rtl_submit_tx_urb(struct ieee80211_hw *hw, struct urb *_urb)
  {
  	int err;
  	struct rtl_priv *rtlpriv = rtl_priv(hw);
  	struct rtl_usb *rtlusb = rtl_usbdev(rtl_usbpriv(hw));
  
  	usb_anchor_urb(_urb, &rtlusb->tx_submitted);
  	err = usb_submit_urb(_urb, GFP_ATOMIC);
  	if (err < 0) {
  		struct sk_buff *skb;
  
  		RT_TRACE(rtlpriv, COMP_USB, DBG_EMERG,
  			 "Failed to submit urb
  ");
  		usb_unanchor_urb(_urb);
  		skb = (struct sk_buff *)_urb->context;
  		kfree_skb(skb);
  	}
  	usb_free_urb(_urb);
  }
  
  static int _usb_tx_post(struct ieee80211_hw *hw, struct urb *urb,
  			struct sk_buff *skb)
  {
  	struct rtl_priv *rtlpriv = rtl_priv(hw);
  	struct rtl_usb *rtlusb = rtl_usbdev(rtl_usbpriv(hw));
  	struct ieee80211_tx_info *txinfo;
  
  	rtlusb->usb_tx_post_hdl(hw, urb, skb);
  	skb_pull(skb, RTL_TX_HEADER_SIZE);
  	txinfo = IEEE80211_SKB_CB(skb);
  	ieee80211_tx_info_clear_status(txinfo);
  	txinfo->flags |= IEEE80211_TX_STAT_ACK;
  
  	if (urb->status) {
  		RT_TRACE(rtlpriv, COMP_USB, DBG_EMERG,
  			 "Urb has error status 0x%X
  ", urb->status);
  		goto out;
  	}
  	/*  TODO:	statistics */
  out:
  	ieee80211_tx_status_irqsafe(hw, skb);
  	return urb->status;
  }
  
  static void _rtl_tx_complete(struct urb *urb)
  {
  	struct sk_buff *skb = (struct sk_buff *)urb->context;
  	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
  	struct rtl_usb *rtlusb = (struct rtl_usb *)info->rate_driver_data[0];
  	struct ieee80211_hw *hw = usb_get_intfdata(rtlusb->intf);
  	int err;
  
  	if (unlikely(IS_USB_STOP(rtlusb)))
  		return;
  	err = _usb_tx_post(hw, urb, skb);
  	if (err) {
  		/* Ignore error and keep issuiing other urbs */
  		return;
  	}
  }
  
  static struct urb *_rtl_usb_tx_urb_setup(struct ieee80211_hw *hw,
  				struct sk_buff *skb, u32 ep_num)
  {
  	struct rtl_priv *rtlpriv = rtl_priv(hw);
  	struct rtl_usb *rtlusb = rtl_usbdev(rtl_usbpriv(hw));
  	struct urb *_urb;
  
  	WARN_ON(NULL == skb);
  	_urb = usb_alloc_urb(0, GFP_ATOMIC);
  	if (!_urb) {
  		RT_TRACE(rtlpriv, COMP_USB, DBG_EMERG,
  			 "Can't allocate URB for bulk out!
  ");
  		kfree_skb(skb);
  		return NULL;
  	}
  	_rtl_install_trx_info(rtlusb, skb, ep_num);
  	usb_fill_bulk_urb(_urb, rtlusb->udev, usb_sndbulkpipe(rtlusb->udev,
  			  ep_num), skb->data, skb->len, _rtl_tx_complete, skb);
  	_urb->transfer_flags |= URB_ZERO_PACKET;
  	return _urb;
  }
  
  static void _rtl_usb_transmit(struct ieee80211_hw *hw, struct sk_buff *skb,
  		       enum rtl_txq qnum)
  {
  	struct rtl_priv *rtlpriv = rtl_priv(hw);
  	struct rtl_usb *rtlusb = rtl_usbdev(rtl_usbpriv(hw));
  	u32 ep_num;
  	struct urb *_urb = NULL;
  	struct sk_buff *_skb = NULL;
  
  	WARN_ON(NULL == rtlusb->usb_tx_aggregate_hdl);
  	if (unlikely(IS_USB_STOP(rtlusb))) {
  		RT_TRACE(rtlpriv, COMP_USB, DBG_EMERG,
  			 "USB device is stopping...
  ");
  		kfree_skb(skb);
  		return;
  	}
  	ep_num = rtlusb->ep_map.ep_mapping[qnum];
  	_skb = skb;
  	_urb = _rtl_usb_tx_urb_setup(hw, _skb, ep_num);
  	if (unlikely(!_urb)) {
  		RT_TRACE(rtlpriv, COMP_ERR, DBG_EMERG,
  			 "Can't allocate urb. Drop skb!
  ");
  		kfree_skb(skb);
  		return;
  	}
  	_rtl_submit_tx_urb(hw, _urb);
  }
  
  static void _rtl_usb_tx_preprocess(struct ieee80211_hw *hw,
  				   struct ieee80211_sta *sta,
  				   struct sk_buff *skb,
  				   u16 hw_queue)
  {
  	struct rtl_priv *rtlpriv = rtl_priv(hw);
  	struct rtl_mac *mac = rtl_mac(rtl_priv(hw));
  	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
  	struct rtl_tx_desc *pdesc = NULL;
  	struct rtl_tcb_desc tcb_desc;
  	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)(skb->data);
  	__le16 fc = hdr->frame_control;
  	u8 *pda_addr = hdr->addr1;
  	/* ssn */
  	u8 *qc = NULL;
  	u8 tid = 0;
  	u16 seq_number = 0;
  
  	memset(&tcb_desc, 0, sizeof(struct rtl_tcb_desc));
  	if (ieee80211_is_auth(fc)) {
  		RT_TRACE(rtlpriv, COMP_SEND, DBG_DMESG, "MAC80211_LINKING
  ");
  		rtl_ips_nic_on(hw);
  	}
  
  	if (rtlpriv->psc.sw_ps_enabled) {
  		if (ieee80211_is_data(fc) && !ieee80211_is_nullfunc(fc) &&
  		    !ieee80211_has_pm(fc))
  			hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_PM);
  	}
  
  	rtl_action_proc(hw, skb, true);
  	if (is_multicast_ether_addr(pda_addr))
  		rtlpriv->stats.txbytesmulticast += skb->len;
  	else if (is_broadcast_ether_addr(pda_addr))
  		rtlpriv->stats.txbytesbroadcast += skb->len;
  	else
  		rtlpriv->stats.txbytesunicast += skb->len;
  	if (ieee80211_is_data_qos(fc)) {
  		qc = ieee80211_get_qos_ctl(hdr);
  		tid = qc[0] & IEEE80211_QOS_CTL_TID_MASK;
  		seq_number = (le16_to_cpu(hdr->seq_ctrl) &
  			     IEEE80211_SCTL_SEQ) >> 4;
  		seq_number += 1;
  		seq_number <<= 4;
  	}
  	rtlpriv->cfg->ops->fill_tx_desc(hw, hdr, (u8 *)pdesc, NULL, info, sta, skb,
  					hw_queue, &tcb_desc);
  	if (!ieee80211_has_morefrags(hdr->frame_control)) {
  		if (qc)
  			mac->tids[tid].seq_number = seq_number;
  	}
  	if (ieee80211_is_data(fc))
  		rtlpriv->cfg->ops->led_control(hw, LED_CTL_TX);
  }
  
  static int rtl_usb_tx(struct ieee80211_hw *hw,
  		      struct ieee80211_sta *sta,
  		      struct sk_buff *skb,
  		      struct rtl_tcb_desc *dummy)
  {
  	struct rtl_usb *rtlusb = rtl_usbdev(rtl_usbpriv(hw));
  	struct rtl_hal *rtlhal = rtl_hal(rtl_priv(hw));
  	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)(skb->data);
  	__le16 fc = hdr->frame_control;
  	u16 hw_queue;
  
  	if (unlikely(is_hal_stop(rtlhal)))
  		goto err_free;
  	hw_queue = rtlusb->usb_mq_to_hwq(fc, skb_get_queue_mapping(skb));
  	_rtl_usb_tx_preprocess(hw, sta, skb, hw_queue);
  	_rtl_usb_transmit(hw, skb, hw_queue);
  	return NETDEV_TX_OK;
  
  err_free:
  	dev_kfree_skb_any(skb);
  	return NETDEV_TX_OK;
  }
  
  static bool rtl_usb_tx_chk_waitq_insert(struct ieee80211_hw *hw,
  					struct ieee80211_sta *sta,
  					struct sk_buff *skb)
  {
  	return false;
  }
  
  static void rtl_fill_h2c_cmd_work_callback(struct work_struct *work)
  {
  	struct rtl_works *rtlworks =
  	    container_of(work, struct rtl_works, fill_h2c_cmd);
  	struct ieee80211_hw *hw = rtlworks->hw;
  	struct rtl_priv *rtlpriv = rtl_priv(hw);
  
  	rtlpriv->cfg->ops->fill_h2c_cmd(hw, H2C_RA_MASK, 5, rtlpriv->rate_mask);
  }
  
  static struct rtl_intf_ops rtl_usb_ops = {
  	.adapter_start = rtl_usb_start,
  	.adapter_stop = rtl_usb_stop,
  	.adapter_tx = rtl_usb_tx,
  	.waitq_insert = rtl_usb_tx_chk_waitq_insert,
  };
  
  int rtl_usb_probe(struct usb_interface *intf,
  		  const struct usb_device_id *id,
  		  struct rtl_hal_cfg *rtl_hal_cfg)
  {
  	int err;
  	struct ieee80211_hw *hw = NULL;
  	struct rtl_priv *rtlpriv = NULL;
  	struct usb_device	*udev;
  	struct rtl_usb_priv *usb_priv;
  
  	hw = ieee80211_alloc_hw(sizeof(struct rtl_priv) +
  				sizeof(struct rtl_usb_priv), &rtl_ops);
  	if (!hw) {
  		RT_ASSERT(false, "ieee80211 alloc failed
  ");
  		return -ENOMEM;
  	}
  	rtlpriv = hw->priv;
  	rtlpriv->usb_data = kzalloc(RTL_USB_MAX_RX_COUNT * sizeof(u32),
  				    GFP_KERNEL);
  	if (!rtlpriv->usb_data)
  		return -ENOMEM;
  
  	/* this spin lock must be initialized early */
  	spin_lock_init(&rtlpriv->locks.usb_lock);
  	INIT_WORK(&rtlpriv->works.fill_h2c_cmd,
  		  rtl_fill_h2c_cmd_work_callback);
  	INIT_WORK(&rtlpriv->works.lps_change_work,
  		  rtl_lps_change_work_callback);
  
  	rtlpriv->usb_data_index = 0;
  	init_completion(&rtlpriv->firmware_loading_complete);
  	SET_IEEE80211_DEV(hw, &intf->dev);
  	udev = interface_to_usbdev(intf);
  	usb_get_dev(udev);
  	usb_priv = rtl_usbpriv(hw);
  	memset(usb_priv, 0, sizeof(*usb_priv));
  	usb_priv->dev.intf = intf;
  	usb_priv->dev.udev = udev;
  	usb_set_intfdata(intf, hw);
  	/* init cfg & intf_ops */
  	rtlpriv->rtlhal.interface = INTF_USB;
  	rtlpriv->cfg = rtl_hal_cfg;
  	rtlpriv->intf_ops = &rtl_usb_ops;
  	rtl_dbgp_flag_init(hw);
  	/* Init IO handler */
  	_rtl_usb_io_handler_init(&udev->dev, hw);
  	rtlpriv->cfg->ops->read_chip_version(hw);
  	/*like read eeprom and so on */
  	rtlpriv->cfg->ops->read_eeprom_info(hw);
  	err = _rtl_usb_init(hw);
  	if (err)
  		goto error_out;
  	rtl_usb_init_sw(hw);
  	/* Init mac80211 sw */
  	err = rtl_init_core(hw);
  	if (err) {
  		RT_TRACE(rtlpriv, COMP_ERR, DBG_EMERG,
  			 "Can't allocate sw for mac80211
  ");
  		goto error_out;
  	}
  	if (rtlpriv->cfg->ops->init_sw_vars(hw)) {
  		RT_TRACE(rtlpriv, COMP_ERR, DBG_EMERG, "Can't init_sw_vars
  ");
  		goto error_out;
  	}
  	rtlpriv->cfg->ops->init_sw_leds(hw);
  
  	err = ieee80211_register_hw(hw);
  	if (err) {
  		RT_TRACE(rtlpriv, COMP_ERR, DBG_EMERG,
  			 "Can't register mac80211 hw.
  ");
  		err = -ENODEV;
  		goto error_out;
  	}
  	rtlpriv->mac80211.mac80211_registered = 1;
  
  	set_bit(RTL_STATUS_INTERFACE_START, &rtlpriv->status);
  	return 0;
  
  error_out:
  	rtl_deinit_core(hw);
  	_rtl_usb_io_handler_release(hw);
  	usb_put_dev(udev);
  	complete(&rtlpriv->firmware_loading_complete);
  	return -ENODEV;
  }
  EXPORT_SYMBOL(rtl_usb_probe);
  
  void rtl_usb_disconnect(struct usb_interface *intf)
  {
  	struct ieee80211_hw *hw = usb_get_intfdata(intf);
  	struct rtl_priv *rtlpriv = rtl_priv(hw);
  	struct rtl_mac *rtlmac = rtl_mac(rtl_priv(hw));
  	struct rtl_usb *rtlusb = rtl_usbdev(rtl_usbpriv(hw));
  
  	if (unlikely(!rtlpriv))
  		return;
  	/* just in case driver is removed before firmware callback */
  	wait_for_completion(&rtlpriv->firmware_loading_complete);
  	clear_bit(RTL_STATUS_INTERFACE_START, &rtlpriv->status);
  	/*ieee80211_unregister_hw will call ops_stop */
  	if (rtlmac->mac80211_registered == 1) {
  		ieee80211_unregister_hw(hw);
  		rtlmac->mac80211_registered = 0;
  	} else {
  		rtl_deinit_deferred_work(hw);
  		rtlpriv->intf_ops->adapter_stop(hw);
  	}
  	/*deinit rfkill */
  	/* rtl_deinit_rfkill(hw); */
  	rtl_usb_deinit(hw);
  	rtl_deinit_core(hw);
  	kfree(rtlpriv->usb_data);
  	rtlpriv->cfg->ops->deinit_sw_leds(hw);
  	rtlpriv->cfg->ops->deinit_sw_vars(hw);
  	_rtl_usb_io_handler_release(hw);
  	usb_put_dev(rtlusb->udev);
  	usb_set_intfdata(intf, NULL);
  	ieee80211_free_hw(hw);
  }
  EXPORT_SYMBOL(rtl_usb_disconnect);
  
  int rtl_usb_suspend(struct usb_interface *pusb_intf, pm_message_t message)
  {
  	return 0;
  }
  EXPORT_SYMBOL(rtl_usb_suspend);
  
  int rtl_usb_resume(struct usb_interface *pusb_intf)
  {
  	return 0;
  }
  EXPORT_SYMBOL(rtl_usb_resume);