1 /*
2  * Copyright (c) 2010-2011 Atheros Communications Inc.
3  *
4  * Permission to use, copy, modify, and/or distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 #include "htc.h"
18 
19 /******/
20 /* TX */
21 /******/
22 
23 static const int subtype_txq_to_hwq[] = {
24 	[WME_AC_BE] = ATH_TXQ_AC_BE,
25 	[WME_AC_BK] = ATH_TXQ_AC_BK,
26 	[WME_AC_VI] = ATH_TXQ_AC_VI,
27 	[WME_AC_VO] = ATH_TXQ_AC_VO,
28 };
29 
30 #define ATH9K_HTC_INIT_TXQ(subtype) do {			\
31 		qi.tqi_subtype = subtype_txq_to_hwq[subtype];	\
32 		qi.tqi_aifs = ATH9K_TXQ_USEDEFAULT;		\
33 		qi.tqi_cwmin = ATH9K_TXQ_USEDEFAULT;		\
34 		qi.tqi_cwmax = ATH9K_TXQ_USEDEFAULT;		\
35 		qi.tqi_physCompBuf = 0;				\
36 		qi.tqi_qflags = TXQ_FLAG_TXEOLINT_ENABLE |	\
37 			TXQ_FLAG_TXDESCINT_ENABLE;		\
38 	} while (0)
39 
40 int get_hw_qnum(u16 queue, int *hwq_map)
41 {
42 	switch (queue) {
43 	case 0:
44 		return hwq_map[WME_AC_VO];
45 	case 1:
46 		return hwq_map[WME_AC_VI];
47 	case 2:
48 		return hwq_map[WME_AC_BE];
49 	case 3:
50 		return hwq_map[WME_AC_BK];
51 	default:
52 		return hwq_map[WME_AC_BE];
53 	}
54 }
55 
56 void ath9k_htc_check_stop_queues(struct ath9k_htc_priv *priv)
57 {
58 	spin_lock_bh(&priv->tx.tx_lock);
59 	priv->tx.queued_cnt++;
60 	if ((priv->tx.queued_cnt >= ATH9K_HTC_TX_THRESHOLD) &&
61 	    !(priv->tx.flags & ATH9K_HTC_OP_TX_QUEUES_STOP)) {
62 		priv->tx.flags |= ATH9K_HTC_OP_TX_QUEUES_STOP;
63 		ieee80211_stop_queues(priv->hw);
64 	}
65 	spin_unlock_bh(&priv->tx.tx_lock);
66 }
67 
68 void ath9k_htc_check_wake_queues(struct ath9k_htc_priv *priv)
69 {
70 	spin_lock_bh(&priv->tx.tx_lock);
71 	if ((priv->tx.queued_cnt < ATH9K_HTC_TX_THRESHOLD) &&
72 	    (priv->tx.flags & ATH9K_HTC_OP_TX_QUEUES_STOP)) {
73 		priv->tx.flags &= ~ATH9K_HTC_OP_TX_QUEUES_STOP;
74 		ieee80211_wake_queues(priv->hw);
75 	}
76 	spin_unlock_bh(&priv->tx.tx_lock);
77 }
78 
79 int ath9k_htc_tx_get_slot(struct ath9k_htc_priv *priv)
80 {
81 	int slot;
82 
83 	spin_lock_bh(&priv->tx.tx_lock);
84 	slot = find_first_zero_bit(priv->tx.tx_slot, MAX_TX_BUF_NUM);
85 	if (slot >= MAX_TX_BUF_NUM) {
86 		spin_unlock_bh(&priv->tx.tx_lock);
87 		return -ENOBUFS;
88 	}
89 	__set_bit(slot, priv->tx.tx_slot);
90 	spin_unlock_bh(&priv->tx.tx_lock);
91 
92 	return slot;
93 }
94 
95 void ath9k_htc_tx_clear_slot(struct ath9k_htc_priv *priv, int slot)
96 {
97 	spin_lock_bh(&priv->tx.tx_lock);
98 	__clear_bit(slot, priv->tx.tx_slot);
99 	spin_unlock_bh(&priv->tx.tx_lock);
100 }
101 
102 static inline enum htc_endpoint_id get_htc_epid(struct ath9k_htc_priv *priv,
103 						u16 qnum)
104 {
105 	enum htc_endpoint_id epid;
106 
107 	switch (qnum) {
108 	case 0:
109 		TX_QSTAT_INC(WME_AC_VO);
110 		epid = priv->data_vo_ep;
111 		break;
112 	case 1:
113 		TX_QSTAT_INC(WME_AC_VI);
114 		epid = priv->data_vi_ep;
115 		break;
116 	case 2:
117 		TX_QSTAT_INC(WME_AC_BE);
118 		epid = priv->data_be_ep;
119 		break;
120 	case 3:
121 	default:
122 		TX_QSTAT_INC(WME_AC_BK);
123 		epid = priv->data_bk_ep;
124 		break;
125 	}
126 
127 	return epid;
128 }
129 
130 static inline struct sk_buff_head*
131 get_htc_epid_queue(struct ath9k_htc_priv *priv, u8 epid)
132 {
133 	struct ath_common *common = ath9k_hw_common(priv->ah);
134 	struct sk_buff_head *epid_queue = NULL;
135 
136 	if (epid == priv->mgmt_ep)
137 		epid_queue = &priv->tx.mgmt_ep_queue;
138 	else if (epid == priv->cab_ep)
139 		epid_queue = &priv->tx.cab_ep_queue;
140 	else if (epid == priv->data_be_ep)
141 		epid_queue = &priv->tx.data_be_queue;
142 	else if (epid == priv->data_bk_ep)
143 		epid_queue = &priv->tx.data_bk_queue;
144 	else if (epid == priv->data_vi_ep)
145 		epid_queue = &priv->tx.data_vi_queue;
146 	else if (epid == priv->data_vo_ep)
147 		epid_queue = &priv->tx.data_vo_queue;
148 	else
149 		ath_err(common, "Invalid EPID: %d\n", epid);
150 
151 	return epid_queue;
152 }
153 
154 /*
155  * Removes the driver header and returns the TX slot number
156  */
157 static inline int strip_drv_header(struct ath9k_htc_priv *priv,
158 				   struct sk_buff *skb)
159 {
160 	struct ath_common *common = ath9k_hw_common(priv->ah);
161 	struct ath9k_htc_tx_ctl *tx_ctl;
162 	int slot;
163 
164 	tx_ctl = HTC_SKB_CB(skb);
165 
166 	if (tx_ctl->epid == priv->mgmt_ep) {
167 		struct tx_mgmt_hdr *tx_mhdr =
168 			(struct tx_mgmt_hdr *)skb->data;
169 		slot = tx_mhdr->cookie;
170 		skb_pull(skb, sizeof(struct tx_mgmt_hdr));
171 	} else if ((tx_ctl->epid == priv->data_bk_ep) ||
172 		   (tx_ctl->epid == priv->data_be_ep) ||
173 		   (tx_ctl->epid == priv->data_vi_ep) ||
174 		   (tx_ctl->epid == priv->data_vo_ep) ||
175 		   (tx_ctl->epid == priv->cab_ep)) {
176 		struct tx_frame_hdr *tx_fhdr =
177 			(struct tx_frame_hdr *)skb->data;
178 		slot = tx_fhdr->cookie;
179 		skb_pull(skb, sizeof(struct tx_frame_hdr));
180 	} else {
181 		ath_err(common, "Unsupported EPID: %d\n", tx_ctl->epid);
182 		slot = -EINVAL;
183 	}
184 
185 	return slot;
186 }
187 
188 int ath_htc_txq_update(struct ath9k_htc_priv *priv, int qnum,
189 		       struct ath9k_tx_queue_info *qinfo)
190 {
191 	struct ath_hw *ah = priv->ah;
192 	int error = 0;
193 	struct ath9k_tx_queue_info qi;
194 
195 	ath9k_hw_get_txq_props(ah, qnum, &qi);
196 
197 	qi.tqi_aifs = qinfo->tqi_aifs;
198 	qi.tqi_cwmin = qinfo->tqi_cwmin / 2; /* XXX */
199 	qi.tqi_cwmax = qinfo->tqi_cwmax;
200 	qi.tqi_burstTime = qinfo->tqi_burstTime;
201 	qi.tqi_readyTime = qinfo->tqi_readyTime;
202 
203 	if (!ath9k_hw_set_txq_props(ah, qnum, &qi)) {
204 		ath_err(ath9k_hw_common(ah),
205 			"Unable to update hardware queue %u!\n", qnum);
206 		error = -EIO;
207 	} else {
208 		ath9k_hw_resettxqueue(ah, qnum);
209 	}
210 
211 	return error;
212 }
213 
214 static void ath9k_htc_tx_mgmt(struct ath9k_htc_priv *priv,
215 			      struct ath9k_htc_vif *avp,
216 			      struct sk_buff *skb,
217 			      u8 sta_idx, u8 vif_idx, u8 slot)
218 {
219 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
220 	struct ieee80211_mgmt *mgmt;
221 	struct ieee80211_hdr *hdr;
222 	struct tx_mgmt_hdr mgmt_hdr;
223 	struct ath9k_htc_tx_ctl *tx_ctl;
224 	u8 *tx_fhdr;
225 
226 	tx_ctl = HTC_SKB_CB(skb);
227 	hdr = (struct ieee80211_hdr *) skb->data;
228 
229 	memset(tx_ctl, 0, sizeof(*tx_ctl));
230 	memset(&mgmt_hdr, 0, sizeof(struct tx_mgmt_hdr));
231 
232 	/*
233 	 * Set the TSF adjust value for probe response
234 	 * frame also.
235 	 */
236 	if (avp && unlikely(ieee80211_is_probe_resp(hdr->frame_control))) {
237 		mgmt = (struct ieee80211_mgmt *)skb->data;
238 		mgmt->u.probe_resp.timestamp = avp->tsfadjust;
239 	}
240 
241 	tx_ctl->type = ATH9K_HTC_MGMT;
242 
243 	mgmt_hdr.node_idx = sta_idx;
244 	mgmt_hdr.vif_idx = vif_idx;
245 	mgmt_hdr.tidno = 0;
246 	mgmt_hdr.flags = 0;
247 	mgmt_hdr.cookie = slot;
248 
249 	mgmt_hdr.key_type = ath9k_cmn_get_hw_crypto_keytype(skb);
250 	if (mgmt_hdr.key_type == ATH9K_KEY_TYPE_CLEAR)
251 		mgmt_hdr.keyix = (u8) ATH9K_TXKEYIX_INVALID;
252 	else
253 		mgmt_hdr.keyix = tx_info->control.hw_key->hw_key_idx;
254 
255 	tx_fhdr = skb_push(skb, sizeof(mgmt_hdr));
256 	memcpy(tx_fhdr, (u8 *) &mgmt_hdr, sizeof(mgmt_hdr));
257 	tx_ctl->epid = priv->mgmt_ep;
258 }
259 
260 static void ath9k_htc_tx_data(struct ath9k_htc_priv *priv,
261 			      struct ieee80211_vif *vif,
262 			      struct sk_buff *skb,
263 			      u8 sta_idx, u8 vif_idx, u8 slot,
264 			      bool is_cab)
265 {
266 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
267 	struct ieee80211_hdr *hdr;
268 	struct ath9k_htc_tx_ctl *tx_ctl;
269 	struct tx_frame_hdr tx_hdr;
270 	u32 flags = 0;
271 	u8 *qc, *tx_fhdr;
272 	u16 qnum;
273 
274 	tx_ctl = HTC_SKB_CB(skb);
275 	hdr = (struct ieee80211_hdr *) skb->data;
276 
277 	memset(tx_ctl, 0, sizeof(*tx_ctl));
278 	memset(&tx_hdr, 0, sizeof(struct tx_frame_hdr));
279 
280 	tx_hdr.node_idx = sta_idx;
281 	tx_hdr.vif_idx = vif_idx;
282 	tx_hdr.cookie = slot;
283 
284 	/*
285 	 * This is a bit redundant but it helps to get
286 	 * the per-packet index quickly when draining the
287 	 * TX queue in the HIF layer. Otherwise we would
288 	 * have to parse the packet contents ...
289 	 */
290 	tx_ctl->sta_idx = sta_idx;
291 
292 	if (tx_info->flags & IEEE80211_TX_CTL_AMPDU) {
293 		tx_ctl->type = ATH9K_HTC_AMPDU;
294 		tx_hdr.data_type = ATH9K_HTC_AMPDU;
295 	} else {
296 		tx_ctl->type = ATH9K_HTC_NORMAL;
297 		tx_hdr.data_type = ATH9K_HTC_NORMAL;
298 	}
299 
300 	if (ieee80211_is_data_qos(hdr->frame_control)) {
301 		qc = ieee80211_get_qos_ctl(hdr);
302 		tx_hdr.tidno = qc[0] & IEEE80211_QOS_CTL_TID_MASK;
303 	}
304 
305 	/* Check for RTS protection */
306 	if (priv->hw->wiphy->rts_threshold != (u32) -1)
307 		if (skb->len > priv->hw->wiphy->rts_threshold)
308 			flags |= ATH9K_HTC_TX_RTSCTS;
309 
310 	/* CTS-to-self */
311 	if (!(flags & ATH9K_HTC_TX_RTSCTS) &&
312 	    (vif && vif->bss_conf.use_cts_prot))
313 		flags |= ATH9K_HTC_TX_CTSONLY;
314 
315 	tx_hdr.flags = cpu_to_be32(flags);
316 	tx_hdr.key_type = ath9k_cmn_get_hw_crypto_keytype(skb);
317 	if (tx_hdr.key_type == ATH9K_KEY_TYPE_CLEAR)
318 		tx_hdr.keyix = (u8) ATH9K_TXKEYIX_INVALID;
319 	else
320 		tx_hdr.keyix = tx_info->control.hw_key->hw_key_idx;
321 
322 	tx_fhdr = skb_push(skb, sizeof(tx_hdr));
323 	memcpy(tx_fhdr, (u8 *) &tx_hdr, sizeof(tx_hdr));
324 
325 	if (is_cab) {
326 		CAB_STAT_INC;
327 		tx_ctl->epid = priv->cab_ep;
328 		return;
329 	}
330 
331 	qnum = skb_get_queue_mapping(skb);
332 	tx_ctl->epid = get_htc_epid(priv, qnum);
333 }
334 
335 int ath9k_htc_tx_start(struct ath9k_htc_priv *priv,
336 		       struct sk_buff *skb,
337 		       u8 slot, bool is_cab)
338 {
339 	struct ieee80211_hdr *hdr;
340 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
341 	struct ieee80211_sta *sta = tx_info->control.sta;
342 	struct ieee80211_vif *vif = tx_info->control.vif;
343 	struct ath9k_htc_sta *ista;
344 	struct ath9k_htc_vif *avp = NULL;
345 	u8 sta_idx, vif_idx;
346 
347 	hdr = (struct ieee80211_hdr *) skb->data;
348 
349 	/*
350 	 * Find out on which interface this packet has to be
351 	 * sent out.
352 	 */
353 	if (vif) {
354 		avp = (struct ath9k_htc_vif *) vif->drv_priv;
355 		vif_idx = avp->index;
356 	} else {
357 		if (!priv->ah->is_monitoring) {
358 			ath_dbg(ath9k_hw_common(priv->ah), ATH_DBG_XMIT,
359 				"VIF is null, but no monitor interface !\n");
360 			return -EINVAL;
361 		}
362 
363 		vif_idx = priv->mon_vif_idx;
364 	}
365 
366 	/*
367 	 * Find out which station this packet is destined for.
368 	 */
369 	if (sta) {
370 		ista = (struct ath9k_htc_sta *) sta->drv_priv;
371 		sta_idx = ista->index;
372 	} else {
373 		sta_idx = priv->vif_sta_pos[vif_idx];
374 	}
375 
376 	if (ieee80211_is_data(hdr->frame_control))
377 		ath9k_htc_tx_data(priv, vif, skb,
378 				  sta_idx, vif_idx, slot, is_cab);
379 	else
380 		ath9k_htc_tx_mgmt(priv, avp, skb,
381 				  sta_idx, vif_idx, slot);
382 
383 
384 	return htc_send(priv->htc, skb);
385 }
386 
387 static inline bool __ath9k_htc_check_tx_aggr(struct ath9k_htc_priv *priv,
388 					     struct ath9k_htc_sta *ista, u8 tid)
389 {
390 	bool ret = false;
391 
392 	spin_lock_bh(&priv->tx.tx_lock);
393 	if ((tid < ATH9K_HTC_MAX_TID) && (ista->tid_state[tid] == AGGR_STOP))
394 		ret = true;
395 	spin_unlock_bh(&priv->tx.tx_lock);
396 
397 	return ret;
398 }
399 
400 static void ath9k_htc_check_tx_aggr(struct ath9k_htc_priv *priv,
401 				    struct ieee80211_vif *vif,
402 				    struct sk_buff *skb)
403 {
404 	struct ieee80211_sta *sta;
405 	struct ieee80211_hdr *hdr;
406 	__le16 fc;
407 
408 	hdr = (struct ieee80211_hdr *) skb->data;
409 	fc = hdr->frame_control;
410 
411 	rcu_read_lock();
412 
413 	sta = ieee80211_find_sta(vif, hdr->addr1);
414 	if (!sta) {
415 		rcu_read_unlock();
416 		return;
417 	}
418 
419 	if (sta && conf_is_ht(&priv->hw->conf) &&
420 	    !(skb->protocol == cpu_to_be16(ETH_P_PAE))) {
421 		if (ieee80211_is_data_qos(fc)) {
422 			u8 *qc, tid;
423 			struct ath9k_htc_sta *ista;
424 
425 			qc = ieee80211_get_qos_ctl(hdr);
426 			tid = qc[0] & 0xf;
427 			ista = (struct ath9k_htc_sta *)sta->drv_priv;
428 			if (__ath9k_htc_check_tx_aggr(priv, ista, tid)) {
429 				ieee80211_start_tx_ba_session(sta, tid, 0);
430 				spin_lock_bh(&priv->tx.tx_lock);
431 				ista->tid_state[tid] = AGGR_PROGRESS;
432 				spin_unlock_bh(&priv->tx.tx_lock);
433 			}
434 		}
435 	}
436 
437 	rcu_read_unlock();
438 }
439 
440 static void ath9k_htc_tx_process(struct ath9k_htc_priv *priv,
441 				 struct sk_buff *skb,
442 				 struct __wmi_event_txstatus *txs)
443 {
444 	struct ieee80211_vif *vif;
445 	struct ath9k_htc_tx_ctl *tx_ctl;
446 	struct ieee80211_tx_info *tx_info;
447 	struct ieee80211_tx_rate *rate;
448 	struct ieee80211_conf *cur_conf = &priv->hw->conf;
449 	bool txok;
450 	int slot;
451 
452 	slot = strip_drv_header(priv, skb);
453 	if (slot < 0) {
454 		dev_kfree_skb_any(skb);
455 		return;
456 	}
457 
458 	tx_ctl = HTC_SKB_CB(skb);
459 	txok = tx_ctl->txok;
460 	tx_info = IEEE80211_SKB_CB(skb);
461 	vif = tx_info->control.vif;
462 	rate = &tx_info->status.rates[0];
463 
464 	memset(&tx_info->status, 0, sizeof(tx_info->status));
465 
466 	/*
467 	 * URB submission failed for this frame, it never reached
468 	 * the target.
469 	 */
470 	if (!txok || !vif || !txs)
471 		goto send_mac80211;
472 
473 	if (txs->ts_flags & ATH9K_HTC_TXSTAT_ACK)
474 		tx_info->flags |= IEEE80211_TX_STAT_ACK;
475 
476 	if (txs->ts_flags & ATH9K_HTC_TXSTAT_FILT)
477 		tx_info->flags |= IEEE80211_TX_STAT_TX_FILTERED;
478 
479 	if (txs->ts_flags & ATH9K_HTC_TXSTAT_RTC_CTS)
480 		rate->flags |= IEEE80211_TX_RC_USE_RTS_CTS;
481 
482 	rate->count = 1;
483 	rate->idx = MS(txs->ts_rate, ATH9K_HTC_TXSTAT_RATE);
484 
485 	if (txs->ts_flags & ATH9K_HTC_TXSTAT_MCS) {
486 		rate->flags |= IEEE80211_TX_RC_MCS;
487 
488 		if (txs->ts_flags & ATH9K_HTC_TXSTAT_CW40)
489 			rate->flags |= IEEE80211_TX_RC_40_MHZ_WIDTH;
490 		if (txs->ts_flags & ATH9K_HTC_TXSTAT_SGI)
491 			rate->flags |= IEEE80211_TX_RC_SHORT_GI;
492 	} else {
493 		if (cur_conf->channel->band == IEEE80211_BAND_5GHZ)
494 			rate->idx += 4; /* No CCK rates */
495 	}
496 
497 	ath9k_htc_check_tx_aggr(priv, vif, skb);
498 
499 send_mac80211:
500 	spin_lock_bh(&priv->tx.tx_lock);
501 	if (WARN_ON(--priv->tx.queued_cnt < 0))
502 		priv->tx.queued_cnt = 0;
503 	spin_unlock_bh(&priv->tx.tx_lock);
504 
505 	ath9k_htc_tx_clear_slot(priv, slot);
506 
507 	/* Send status to mac80211 */
508 	ieee80211_tx_status(priv->hw, skb);
509 }
510 
511 static inline void ath9k_htc_tx_drainq(struct ath9k_htc_priv *priv,
512 				       struct sk_buff_head *queue)
513 {
514 	struct sk_buff *skb;
515 
516 	while ((skb = skb_dequeue(queue)) != NULL) {
517 		ath9k_htc_tx_process(priv, skb, NULL);
518 	}
519 }
520 
521 void ath9k_htc_tx_drain(struct ath9k_htc_priv *priv)
522 {
523 	struct ath9k_htc_tx_event *event, *tmp;
524 
525 	spin_lock_bh(&priv->tx.tx_lock);
526 	priv->tx.flags |= ATH9K_HTC_OP_TX_DRAIN;
527 	spin_unlock_bh(&priv->tx.tx_lock);
528 
529 	/*
530 	 * Ensure that all pending TX frames are flushed,
531 	 * and that the TX completion/failed tasklets is killed.
532 	 */
533 	htc_stop(priv->htc);
534 	tasklet_kill(&priv->wmi->wmi_event_tasklet);
535 	tasklet_kill(&priv->tx_failed_tasklet);
536 
537 	ath9k_htc_tx_drainq(priv, &priv->tx.mgmt_ep_queue);
538 	ath9k_htc_tx_drainq(priv, &priv->tx.cab_ep_queue);
539 	ath9k_htc_tx_drainq(priv, &priv->tx.data_be_queue);
540 	ath9k_htc_tx_drainq(priv, &priv->tx.data_bk_queue);
541 	ath9k_htc_tx_drainq(priv, &priv->tx.data_vi_queue);
542 	ath9k_htc_tx_drainq(priv, &priv->tx.data_vo_queue);
543 	ath9k_htc_tx_drainq(priv, &priv->tx.tx_failed);
544 
545 	/*
546 	 * The TX cleanup timer has already been killed.
547 	 */
548 	spin_lock_bh(&priv->wmi->event_lock);
549 	list_for_each_entry_safe(event, tmp, &priv->wmi->pending_tx_events, list) {
550 		list_del(&event->list);
551 		kfree(event);
552 	}
553 	spin_unlock_bh(&priv->wmi->event_lock);
554 
555 	spin_lock_bh(&priv->tx.tx_lock);
556 	priv->tx.flags &= ~ATH9K_HTC_OP_TX_DRAIN;
557 	spin_unlock_bh(&priv->tx.tx_lock);
558 }
559 
560 void ath9k_tx_failed_tasklet(unsigned long data)
561 {
562 	struct ath9k_htc_priv *priv = (struct ath9k_htc_priv *)data;
563 
564 	spin_lock_bh(&priv->tx.tx_lock);
565 	if (priv->tx.flags & ATH9K_HTC_OP_TX_DRAIN) {
566 		spin_unlock_bh(&priv->tx.tx_lock);
567 		return;
568 	}
569 	spin_unlock_bh(&priv->tx.tx_lock);
570 
571 	ath9k_htc_tx_drainq(priv, &priv->tx.tx_failed);
572 }
573 
574 static inline bool check_cookie(struct ath9k_htc_priv *priv,
575 				struct sk_buff *skb,
576 				u8 cookie, u8 epid)
577 {
578 	u8 fcookie = 0;
579 
580 	if (epid == priv->mgmt_ep) {
581 		struct tx_mgmt_hdr *hdr;
582 		hdr = (struct tx_mgmt_hdr *) skb->data;
583 		fcookie = hdr->cookie;
584 	} else if ((epid == priv->data_bk_ep) ||
585 		   (epid == priv->data_be_ep) ||
586 		   (epid == priv->data_vi_ep) ||
587 		   (epid == priv->data_vo_ep) ||
588 		   (epid == priv->cab_ep)) {
589 		struct tx_frame_hdr *hdr;
590 		hdr = (struct tx_frame_hdr *) skb->data;
591 		fcookie = hdr->cookie;
592 	}
593 
594 	if (fcookie == cookie)
595 		return true;
596 
597 	return false;
598 }
599 
600 static struct sk_buff* ath9k_htc_tx_get_packet(struct ath9k_htc_priv *priv,
601 					       struct __wmi_event_txstatus *txs)
602 {
603 	struct ath_common *common = ath9k_hw_common(priv->ah);
604 	struct sk_buff_head *epid_queue;
605 	struct sk_buff *skb, *tmp;
606 	unsigned long flags;
607 	u8 epid = MS(txs->ts_rate, ATH9K_HTC_TXSTAT_EPID);
608 
609 	epid_queue = get_htc_epid_queue(priv, epid);
610 	if (!epid_queue)
611 		return NULL;
612 
613 	spin_lock_irqsave(&epid_queue->lock, flags);
614 	skb_queue_walk_safe(epid_queue, skb, tmp) {
615 		if (check_cookie(priv, skb, txs->cookie, epid)) {
616 			__skb_unlink(skb, epid_queue);
617 			spin_unlock_irqrestore(&epid_queue->lock, flags);
618 			return skb;
619 		}
620 	}
621 	spin_unlock_irqrestore(&epid_queue->lock, flags);
622 
623 	ath_dbg(common, ATH_DBG_XMIT,
624 		"No matching packet for cookie: %d, epid: %d\n",
625 		txs->cookie, epid);
626 
627 	return NULL;
628 }
629 
630 void ath9k_htc_txstatus(struct ath9k_htc_priv *priv, void *wmi_event)
631 {
632 	struct wmi_event_txstatus *txs = (struct wmi_event_txstatus *)wmi_event;
633 	struct __wmi_event_txstatus *__txs;
634 	struct sk_buff *skb;
635 	struct ath9k_htc_tx_event *tx_pend;
636 	int i;
637 
638 	for (i = 0; i < txs->cnt; i++) {
639 		WARN_ON(txs->cnt > HTC_MAX_TX_STATUS);
640 
641 		__txs = &txs->txstatus[i];
642 
643 		skb = ath9k_htc_tx_get_packet(priv, __txs);
644 		if (!skb) {
645 			/*
646 			 * Store this event, so that the TX cleanup
647 			 * routine can check later for the needed packet.
648 			 */
649 			tx_pend = kzalloc(sizeof(struct ath9k_htc_tx_event),
650 					  GFP_ATOMIC);
651 			if (!tx_pend)
652 				continue;
653 
654 			memcpy(&tx_pend->txs, __txs,
655 			       sizeof(struct __wmi_event_txstatus));
656 
657 			spin_lock(&priv->wmi->event_lock);
658 			list_add_tail(&tx_pend->list,
659 				      &priv->wmi->pending_tx_events);
660 			spin_unlock(&priv->wmi->event_lock);
661 
662 			continue;
663 		}
664 
665 		ath9k_htc_tx_process(priv, skb, __txs);
666 	}
667 
668 	/* Wake TX queues if needed */
669 	ath9k_htc_check_wake_queues(priv);
670 }
671 
672 void ath9k_htc_txep(void *drv_priv, struct sk_buff *skb,
673 		    enum htc_endpoint_id ep_id, bool txok)
674 {
675 	struct ath9k_htc_priv *priv = (struct ath9k_htc_priv *) drv_priv;
676 	struct ath9k_htc_tx_ctl *tx_ctl;
677 	struct sk_buff_head *epid_queue;
678 
679 	tx_ctl = HTC_SKB_CB(skb);
680 	tx_ctl->txok = txok;
681 	tx_ctl->timestamp = jiffies;
682 
683 	if (!txok) {
684 		skb_queue_tail(&priv->tx.tx_failed, skb);
685 		tasklet_schedule(&priv->tx_failed_tasklet);
686 		return;
687 	}
688 
689 	epid_queue = get_htc_epid_queue(priv, ep_id);
690 	if (!epid_queue) {
691 		dev_kfree_skb_any(skb);
692 		return;
693 	}
694 
695 	skb_queue_tail(epid_queue, skb);
696 }
697 
698 static inline bool check_packet(struct ath9k_htc_priv *priv, struct sk_buff *skb)
699 {
700 	struct ath_common *common = ath9k_hw_common(priv->ah);
701 	struct ath9k_htc_tx_ctl *tx_ctl;
702 
703 	tx_ctl = HTC_SKB_CB(skb);
704 
705 	if (time_after(jiffies,
706 		       tx_ctl->timestamp +
707 		       msecs_to_jiffies(ATH9K_HTC_TX_TIMEOUT_INTERVAL))) {
708 		ath_dbg(common, ATH_DBG_XMIT,
709 			"Dropping a packet due to TX timeout\n");
710 		return true;
711 	}
712 
713 	return false;
714 }
715 
716 static void ath9k_htc_tx_cleanup_queue(struct ath9k_htc_priv *priv,
717 				       struct sk_buff_head *epid_queue)
718 {
719 	bool process = false;
720 	unsigned long flags;
721 	struct sk_buff *skb, *tmp;
722 	struct sk_buff_head queue;
723 
724 	skb_queue_head_init(&queue);
725 
726 	spin_lock_irqsave(&epid_queue->lock, flags);
727 	skb_queue_walk_safe(epid_queue, skb, tmp) {
728 		if (check_packet(priv, skb)) {
729 			__skb_unlink(skb, epid_queue);
730 			__skb_queue_tail(&queue, skb);
731 			process = true;
732 		}
733 	}
734 	spin_unlock_irqrestore(&epid_queue->lock, flags);
735 
736 	if (process) {
737 		skb_queue_walk_safe(&queue, skb, tmp) {
738 			__skb_unlink(skb, &queue);
739 			ath9k_htc_tx_process(priv, skb, NULL);
740 		}
741 	}
742 }
743 
744 void ath9k_htc_tx_cleanup_timer(unsigned long data)
745 {
746 	struct ath9k_htc_priv *priv = (struct ath9k_htc_priv *) data;
747 	struct ath_common *common = ath9k_hw_common(priv->ah);
748 	struct ath9k_htc_tx_event *event, *tmp;
749 	struct sk_buff *skb;
750 
751 	spin_lock(&priv->wmi->event_lock);
752 	list_for_each_entry_safe(event, tmp, &priv->wmi->pending_tx_events, list) {
753 
754 		skb = ath9k_htc_tx_get_packet(priv, &event->txs);
755 		if (skb) {
756 			ath_dbg(common, ATH_DBG_XMIT,
757 				"Found packet for cookie: %d, epid: %d\n",
758 				event->txs.cookie,
759 				MS(event->txs.ts_rate, ATH9K_HTC_TXSTAT_EPID));
760 
761 			ath9k_htc_tx_process(priv, skb, &event->txs);
762 			list_del(&event->list);
763 			kfree(event);
764 			continue;
765 		}
766 
767 		if (++event->count >= ATH9K_HTC_TX_TIMEOUT_COUNT) {
768 			list_del(&event->list);
769 			kfree(event);
770 		}
771 	}
772 	spin_unlock(&priv->wmi->event_lock);
773 
774 	/*
775 	 * Check if status-pending packets have to be cleaned up.
776 	 */
777 	ath9k_htc_tx_cleanup_queue(priv, &priv->tx.mgmt_ep_queue);
778 	ath9k_htc_tx_cleanup_queue(priv, &priv->tx.cab_ep_queue);
779 	ath9k_htc_tx_cleanup_queue(priv, &priv->tx.data_be_queue);
780 	ath9k_htc_tx_cleanup_queue(priv, &priv->tx.data_bk_queue);
781 	ath9k_htc_tx_cleanup_queue(priv, &priv->tx.data_vi_queue);
782 	ath9k_htc_tx_cleanup_queue(priv, &priv->tx.data_vo_queue);
783 
784 	/* Wake TX queues if needed */
785 	ath9k_htc_check_wake_queues(priv);
786 
787 	mod_timer(&priv->tx.cleanup_timer,
788 		  jiffies + msecs_to_jiffies(ATH9K_HTC_TX_CLEANUP_INTERVAL));
789 }
790 
791 int ath9k_tx_init(struct ath9k_htc_priv *priv)
792 {
793 	skb_queue_head_init(&priv->tx.mgmt_ep_queue);
794 	skb_queue_head_init(&priv->tx.cab_ep_queue);
795 	skb_queue_head_init(&priv->tx.data_be_queue);
796 	skb_queue_head_init(&priv->tx.data_bk_queue);
797 	skb_queue_head_init(&priv->tx.data_vi_queue);
798 	skb_queue_head_init(&priv->tx.data_vo_queue);
799 	skb_queue_head_init(&priv->tx.tx_failed);
800 	return 0;
801 }
802 
803 void ath9k_tx_cleanup(struct ath9k_htc_priv *priv)
804 {
805 
806 }
807 
808 bool ath9k_htc_txq_setup(struct ath9k_htc_priv *priv, int subtype)
809 {
810 	struct ath_hw *ah = priv->ah;
811 	struct ath_common *common = ath9k_hw_common(ah);
812 	struct ath9k_tx_queue_info qi;
813 	int qnum;
814 
815 	memset(&qi, 0, sizeof(qi));
816 	ATH9K_HTC_INIT_TXQ(subtype);
817 
818 	qnum = ath9k_hw_setuptxqueue(priv->ah, ATH9K_TX_QUEUE_DATA, &qi);
819 	if (qnum == -1)
820 		return false;
821 
822 	if (qnum >= ARRAY_SIZE(priv->hwq_map)) {
823 		ath_err(common, "qnum %u out of range, max %zu!\n",
824 			qnum, ARRAY_SIZE(priv->hwq_map));
825 		ath9k_hw_releasetxqueue(ah, qnum);
826 		return false;
827 	}
828 
829 	priv->hwq_map[subtype] = qnum;
830 	return true;
831 }
832 
833 int ath9k_htc_cabq_setup(struct ath9k_htc_priv *priv)
834 {
835 	struct ath9k_tx_queue_info qi;
836 
837 	memset(&qi, 0, sizeof(qi));
838 	ATH9K_HTC_INIT_TXQ(0);
839 
840 	return ath9k_hw_setuptxqueue(priv->ah, ATH9K_TX_QUEUE_CAB, &qi);
841 }
842 
843 /******/
844 /* RX */
845 /******/
846 
847 /*
848  * Calculate the RX filter to be set in the HW.
849  */
850 u32 ath9k_htc_calcrxfilter(struct ath9k_htc_priv *priv)
851 {
852 #define	RX_FILTER_PRESERVE (ATH9K_RX_FILTER_PHYERR | ATH9K_RX_FILTER_PHYRADAR)
853 
854 	struct ath_hw *ah = priv->ah;
855 	u32 rfilt;
856 
857 	rfilt = (ath9k_hw_getrxfilter(ah) & RX_FILTER_PRESERVE)
858 		| ATH9K_RX_FILTER_UCAST | ATH9K_RX_FILTER_BCAST
859 		| ATH9K_RX_FILTER_MCAST;
860 
861 	if (priv->rxfilter & FIF_PROBE_REQ)
862 		rfilt |= ATH9K_RX_FILTER_PROBEREQ;
863 
864 	/*
865 	 * Set promiscuous mode when FIF_PROMISC_IN_BSS is enabled for station
866 	 * mode interface or when in monitor mode. AP mode does not need this
867 	 * since it receives all in-BSS frames anyway.
868 	 */
869 	if (((ah->opmode != NL80211_IFTYPE_AP) &&
870 	     (priv->rxfilter & FIF_PROMISC_IN_BSS)) ||
871 	    ah->is_monitoring)
872 		rfilt |= ATH9K_RX_FILTER_PROM;
873 
874 	if (priv->rxfilter & FIF_CONTROL)
875 		rfilt |= ATH9K_RX_FILTER_CONTROL;
876 
877 	if ((ah->opmode == NL80211_IFTYPE_STATION) &&
878 	    (priv->nvifs <= 1) &&
879 	    !(priv->rxfilter & FIF_BCN_PRBRESP_PROMISC))
880 		rfilt |= ATH9K_RX_FILTER_MYBEACON;
881 	else
882 		rfilt |= ATH9K_RX_FILTER_BEACON;
883 
884 	if (conf_is_ht(&priv->hw->conf)) {
885 		rfilt |= ATH9K_RX_FILTER_COMP_BAR;
886 		rfilt |= ATH9K_RX_FILTER_UNCOMP_BA_BAR;
887 	}
888 
889 	if (priv->rxfilter & FIF_PSPOLL)
890 		rfilt |= ATH9K_RX_FILTER_PSPOLL;
891 
892 	if (priv->nvifs > 1)
893 		rfilt |= ATH9K_RX_FILTER_MCAST_BCAST_ALL;
894 
895 	return rfilt;
896 
897 #undef RX_FILTER_PRESERVE
898 }
899 
900 /*
901  * Recv initialization for opmode change.
902  */
903 static void ath9k_htc_opmode_init(struct ath9k_htc_priv *priv)
904 {
905 	struct ath_hw *ah = priv->ah;
906 	u32 rfilt, mfilt[2];
907 
908 	/* configure rx filter */
909 	rfilt = ath9k_htc_calcrxfilter(priv);
910 	ath9k_hw_setrxfilter(ah, rfilt);
911 
912 	/* calculate and install multicast filter */
913 	mfilt[0] = mfilt[1] = ~0;
914 	ath9k_hw_setmcastfilter(ah, mfilt[0], mfilt[1]);
915 }
916 
917 void ath9k_host_rx_init(struct ath9k_htc_priv *priv)
918 {
919 	ath9k_hw_rxena(priv->ah);
920 	ath9k_htc_opmode_init(priv);
921 	ath9k_hw_startpcureceive(priv->ah, (priv->op_flags & OP_SCANNING));
922 	priv->rx.last_rssi = ATH_RSSI_DUMMY_MARKER;
923 }
924 
925 static void ath9k_process_rate(struct ieee80211_hw *hw,
926 			       struct ieee80211_rx_status *rxs,
927 			       u8 rx_rate, u8 rs_flags)
928 {
929 	struct ieee80211_supported_band *sband;
930 	enum ieee80211_band band;
931 	unsigned int i = 0;
932 
933 	if (rx_rate & 0x80) {
934 		/* HT rate */
935 		rxs->flag |= RX_FLAG_HT;
936 		if (rs_flags & ATH9K_RX_2040)
937 			rxs->flag |= RX_FLAG_40MHZ;
938 		if (rs_flags & ATH9K_RX_GI)
939 			rxs->flag |= RX_FLAG_SHORT_GI;
940 		rxs->rate_idx = rx_rate & 0x7f;
941 		return;
942 	}
943 
944 	band = hw->conf.channel->band;
945 	sband = hw->wiphy->bands[band];
946 
947 	for (i = 0; i < sband->n_bitrates; i++) {
948 		if (sband->bitrates[i].hw_value == rx_rate) {
949 			rxs->rate_idx = i;
950 			return;
951 		}
952 		if (sband->bitrates[i].hw_value_short == rx_rate) {
953 			rxs->rate_idx = i;
954 			rxs->flag |= RX_FLAG_SHORTPRE;
955 			return;
956 		}
957 	}
958 
959 }
960 
961 static bool ath9k_rx_prepare(struct ath9k_htc_priv *priv,
962 			     struct ath9k_htc_rxbuf *rxbuf,
963 			     struct ieee80211_rx_status *rx_status)
964 
965 {
966 	struct ieee80211_hdr *hdr;
967 	struct ieee80211_hw *hw = priv->hw;
968 	struct sk_buff *skb = rxbuf->skb;
969 	struct ath_common *common = ath9k_hw_common(priv->ah);
970 	struct ath_htc_rx_status *rxstatus;
971 	int hdrlen, padpos, padsize;
972 	int last_rssi = ATH_RSSI_DUMMY_MARKER;
973 	__le16 fc;
974 
975 	if (skb->len < HTC_RX_FRAME_HEADER_SIZE) {
976 		ath_err(common, "Corrupted RX frame, dropping (len: %d)\n",
977 			skb->len);
978 		goto rx_next;
979 	}
980 
981 	rxstatus = (struct ath_htc_rx_status *)skb->data;
982 
983 	if (be16_to_cpu(rxstatus->rs_datalen) -
984 	    (skb->len - HTC_RX_FRAME_HEADER_SIZE) != 0) {
985 		ath_err(common,
986 			"Corrupted RX data len, dropping (dlen: %d, skblen: %d)\n",
987 			rxstatus->rs_datalen, skb->len);
988 		goto rx_next;
989 	}
990 
991 	ath9k_htc_err_stat_rx(priv, rxstatus);
992 
993 	/* Get the RX status information */
994 	memcpy(&rxbuf->rxstatus, rxstatus, HTC_RX_FRAME_HEADER_SIZE);
995 	skb_pull(skb, HTC_RX_FRAME_HEADER_SIZE);
996 
997 	hdr = (struct ieee80211_hdr *)skb->data;
998 	fc = hdr->frame_control;
999 	hdrlen = ieee80211_get_hdrlen_from_skb(skb);
1000 
1001 	padpos = ath9k_cmn_padpos(fc);
1002 
1003 	padsize = padpos & 3;
1004 	if (padsize && skb->len >= padpos+padsize+FCS_LEN) {
1005 		memmove(skb->data + padsize, skb->data, padpos);
1006 		skb_pull(skb, padsize);
1007 	}
1008 
1009 	memset(rx_status, 0, sizeof(struct ieee80211_rx_status));
1010 
1011 	if (rxbuf->rxstatus.rs_status != 0) {
1012 		if (rxbuf->rxstatus.rs_status & ATH9K_RXERR_CRC)
1013 			rx_status->flag |= RX_FLAG_FAILED_FCS_CRC;
1014 		if (rxbuf->rxstatus.rs_status & ATH9K_RXERR_PHY)
1015 			goto rx_next;
1016 
1017 		if (rxbuf->rxstatus.rs_status & ATH9K_RXERR_DECRYPT) {
1018 			/* FIXME */
1019 		} else if (rxbuf->rxstatus.rs_status & ATH9K_RXERR_MIC) {
1020 			if (ieee80211_is_ctl(fc))
1021 				/*
1022 				 * Sometimes, we get invalid
1023 				 * MIC failures on valid control frames.
1024 				 * Remove these mic errors.
1025 				 */
1026 				rxbuf->rxstatus.rs_status &= ~ATH9K_RXERR_MIC;
1027 			else
1028 				rx_status->flag |= RX_FLAG_MMIC_ERROR;
1029 		}
1030 
1031 		/*
1032 		 * Reject error frames with the exception of
1033 		 * decryption and MIC failures. For monitor mode,
1034 		 * we also ignore the CRC error.
1035 		 */
1036 		if (priv->ah->opmode == NL80211_IFTYPE_MONITOR) {
1037 			if (rxbuf->rxstatus.rs_status &
1038 			    ~(ATH9K_RXERR_DECRYPT | ATH9K_RXERR_MIC |
1039 			      ATH9K_RXERR_CRC))
1040 				goto rx_next;
1041 		} else {
1042 			if (rxbuf->rxstatus.rs_status &
1043 			    ~(ATH9K_RXERR_DECRYPT | ATH9K_RXERR_MIC)) {
1044 				goto rx_next;
1045 			}
1046 		}
1047 	}
1048 
1049 	if (!(rxbuf->rxstatus.rs_status & ATH9K_RXERR_DECRYPT)) {
1050 		u8 keyix;
1051 		keyix = rxbuf->rxstatus.rs_keyix;
1052 		if (keyix != ATH9K_RXKEYIX_INVALID) {
1053 			rx_status->flag |= RX_FLAG_DECRYPTED;
1054 		} else if (ieee80211_has_protected(fc) &&
1055 			   skb->len >= hdrlen + 4) {
1056 			keyix = skb->data[hdrlen + 3] >> 6;
1057 			if (test_bit(keyix, common->keymap))
1058 				rx_status->flag |= RX_FLAG_DECRYPTED;
1059 		}
1060 	}
1061 
1062 	ath9k_process_rate(hw, rx_status, rxbuf->rxstatus.rs_rate,
1063 			   rxbuf->rxstatus.rs_flags);
1064 
1065 	if (rxbuf->rxstatus.rs_rssi != ATH9K_RSSI_BAD &&
1066 	    !rxbuf->rxstatus.rs_moreaggr)
1067 		ATH_RSSI_LPF(priv->rx.last_rssi,
1068 			     rxbuf->rxstatus.rs_rssi);
1069 
1070 	last_rssi = priv->rx.last_rssi;
1071 
1072 	if (likely(last_rssi != ATH_RSSI_DUMMY_MARKER))
1073 		rxbuf->rxstatus.rs_rssi = ATH_EP_RND(last_rssi,
1074 						     ATH_RSSI_EP_MULTIPLIER);
1075 
1076 	if (rxbuf->rxstatus.rs_rssi < 0)
1077 		rxbuf->rxstatus.rs_rssi = 0;
1078 
1079 	if (ieee80211_is_beacon(fc))
1080 		priv->ah->stats.avgbrssi = rxbuf->rxstatus.rs_rssi;
1081 
1082 	rx_status->mactime = be64_to_cpu(rxbuf->rxstatus.rs_tstamp);
1083 	rx_status->band = hw->conf.channel->band;
1084 	rx_status->freq = hw->conf.channel->center_freq;
1085 	rx_status->signal =  rxbuf->rxstatus.rs_rssi + ATH_DEFAULT_NOISE_FLOOR;
1086 	rx_status->antenna = rxbuf->rxstatus.rs_antenna;
1087 	rx_status->flag |= RX_FLAG_MACTIME_MPDU;
1088 
1089 	return true;
1090 
1091 rx_next:
1092 	return false;
1093 }
1094 
1095 /*
1096  * FIXME: Handle FLUSH later on.
1097  */
1098 void ath9k_rx_tasklet(unsigned long data)
1099 {
1100 	struct ath9k_htc_priv *priv = (struct ath9k_htc_priv *)data;
1101 	struct ath9k_htc_rxbuf *rxbuf = NULL, *tmp_buf = NULL;
1102 	struct ieee80211_rx_status rx_status;
1103 	struct sk_buff *skb;
1104 	unsigned long flags;
1105 	struct ieee80211_hdr *hdr;
1106 
1107 	do {
1108 		spin_lock_irqsave(&priv->rx.rxbuflock, flags);
1109 		list_for_each_entry(tmp_buf, &priv->rx.rxbuf, list) {
1110 			if (tmp_buf->in_process) {
1111 				rxbuf = tmp_buf;
1112 				break;
1113 			}
1114 		}
1115 
1116 		if (rxbuf == NULL) {
1117 			spin_unlock_irqrestore(&priv->rx.rxbuflock, flags);
1118 			break;
1119 		}
1120 
1121 		if (!rxbuf->skb)
1122 			goto requeue;
1123 
1124 		if (!ath9k_rx_prepare(priv, rxbuf, &rx_status)) {
1125 			dev_kfree_skb_any(rxbuf->skb);
1126 			goto requeue;
1127 		}
1128 
1129 		memcpy(IEEE80211_SKB_RXCB(rxbuf->skb), &rx_status,
1130 		       sizeof(struct ieee80211_rx_status));
1131 		skb = rxbuf->skb;
1132 		hdr = (struct ieee80211_hdr *) skb->data;
1133 
1134 		if (ieee80211_is_beacon(hdr->frame_control) && priv->ps_enabled)
1135 				ieee80211_queue_work(priv->hw, &priv->ps_work);
1136 
1137 		spin_unlock_irqrestore(&priv->rx.rxbuflock, flags);
1138 
1139 		ieee80211_rx(priv->hw, skb);
1140 
1141 		spin_lock_irqsave(&priv->rx.rxbuflock, flags);
1142 requeue:
1143 		rxbuf->in_process = false;
1144 		rxbuf->skb = NULL;
1145 		list_move_tail(&rxbuf->list, &priv->rx.rxbuf);
1146 		rxbuf = NULL;
1147 		spin_unlock_irqrestore(&priv->rx.rxbuflock, flags);
1148 	} while (1);
1149 
1150 }
1151 
1152 void ath9k_htc_rxep(void *drv_priv, struct sk_buff *skb,
1153 		    enum htc_endpoint_id ep_id)
1154 {
1155 	struct ath9k_htc_priv *priv = (struct ath9k_htc_priv *)drv_priv;
1156 	struct ath_hw *ah = priv->ah;
1157 	struct ath_common *common = ath9k_hw_common(ah);
1158 	struct ath9k_htc_rxbuf *rxbuf = NULL, *tmp_buf = NULL;
1159 
1160 	spin_lock(&priv->rx.rxbuflock);
1161 	list_for_each_entry(tmp_buf, &priv->rx.rxbuf, list) {
1162 		if (!tmp_buf->in_process) {
1163 			rxbuf = tmp_buf;
1164 			break;
1165 		}
1166 	}
1167 	spin_unlock(&priv->rx.rxbuflock);
1168 
1169 	if (rxbuf == NULL) {
1170 		ath_dbg(common, ATH_DBG_ANY,
1171 			"No free RX buffer\n");
1172 		goto err;
1173 	}
1174 
1175 	spin_lock(&priv->rx.rxbuflock);
1176 	rxbuf->skb = skb;
1177 	rxbuf->in_process = true;
1178 	spin_unlock(&priv->rx.rxbuflock);
1179 
1180 	tasklet_schedule(&priv->rx_tasklet);
1181 	return;
1182 err:
1183 	dev_kfree_skb_any(skb);
1184 }
1185 
1186 /* FIXME: Locking for cleanup/init */
1187 
1188 void ath9k_rx_cleanup(struct ath9k_htc_priv *priv)
1189 {
1190 	struct ath9k_htc_rxbuf *rxbuf, *tbuf;
1191 
1192 	list_for_each_entry_safe(rxbuf, tbuf, &priv->rx.rxbuf, list) {
1193 		list_del(&rxbuf->list);
1194 		if (rxbuf->skb)
1195 			dev_kfree_skb_any(rxbuf->skb);
1196 		kfree(rxbuf);
1197 	}
1198 }
1199 
1200 int ath9k_rx_init(struct ath9k_htc_priv *priv)
1201 {
1202 	struct ath_hw *ah = priv->ah;
1203 	struct ath_common *common = ath9k_hw_common(ah);
1204 	struct ath9k_htc_rxbuf *rxbuf;
1205 	int i = 0;
1206 
1207 	INIT_LIST_HEAD(&priv->rx.rxbuf);
1208 	spin_lock_init(&priv->rx.rxbuflock);
1209 
1210 	for (i = 0; i < ATH9K_HTC_RXBUF; i++) {
1211 		rxbuf = kzalloc(sizeof(struct ath9k_htc_rxbuf), GFP_KERNEL);
1212 		if (rxbuf == NULL) {
1213 			ath_err(common, "Unable to allocate RX buffers\n");
1214 			goto err;
1215 		}
1216 		list_add_tail(&rxbuf->list, &priv->rx.rxbuf);
1217 	}
1218 
1219 	return 0;
1220 
1221 err:
1222 	ath9k_rx_cleanup(priv);
1223 	return -ENOMEM;
1224 }
1225