recv.c revision 9c1d8e4affe6748d884a677cf5db19ae0c20ef07
1/*
2 * Copyright (c) 2008-2009 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 "ath9k.h"
18#include "ar9003_mac.h"
19
20#define SKB_CB_ATHBUF(__skb)	(*((struct ath_buf **)__skb->cb))
21
22static inline bool ath_is_alt_ant_ratio_better(int alt_ratio, int maxdelta,
23					       int mindelta, int main_rssi_avg,
24					       int alt_rssi_avg, int pkt_count)
25{
26	return (((alt_ratio >= ATH_ANT_DIV_COMB_ALT_ANT_RATIO2) &&
27		(alt_rssi_avg > main_rssi_avg + maxdelta)) ||
28		(alt_rssi_avg > main_rssi_avg + mindelta)) && (pkt_count > 50);
29}
30
31static inline bool ath9k_check_auto_sleep(struct ath_softc *sc)
32{
33	return sc->ps_enabled &&
34	       (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_AUTOSLEEP);
35}
36
37static struct ieee80211_hw * ath_get_virt_hw(struct ath_softc *sc,
38					     struct ieee80211_hdr *hdr)
39{
40	struct ieee80211_hw *hw = sc->pri_wiphy->hw;
41	int i;
42
43	spin_lock_bh(&sc->wiphy_lock);
44	for (i = 0; i < sc->num_sec_wiphy; i++) {
45		struct ath_wiphy *aphy = sc->sec_wiphy[i];
46		if (aphy == NULL)
47			continue;
48		if (compare_ether_addr(hdr->addr1, aphy->hw->wiphy->perm_addr)
49		    == 0) {
50			hw = aphy->hw;
51			break;
52		}
53	}
54	spin_unlock_bh(&sc->wiphy_lock);
55	return hw;
56}
57
58/*
59 * Setup and link descriptors.
60 *
61 * 11N: we can no longer afford to self link the last descriptor.
62 * MAC acknowledges BA status as long as it copies frames to host
63 * buffer (or rx fifo). This can incorrectly acknowledge packets
64 * to a sender if last desc is self-linked.
65 */
66static void ath_rx_buf_link(struct ath_softc *sc, struct ath_buf *bf)
67{
68	struct ath_hw *ah = sc->sc_ah;
69	struct ath_common *common = ath9k_hw_common(ah);
70	struct ath_desc *ds;
71	struct sk_buff *skb;
72
73	ATH_RXBUF_RESET(bf);
74
75	ds = bf->bf_desc;
76	ds->ds_link = 0; /* link to null */
77	ds->ds_data = bf->bf_buf_addr;
78
79	/* virtual addr of the beginning of the buffer. */
80	skb = bf->bf_mpdu;
81	BUG_ON(skb == NULL);
82	ds->ds_vdata = skb->data;
83
84	/*
85	 * setup rx descriptors. The rx_bufsize here tells the hardware
86	 * how much data it can DMA to us and that we are prepared
87	 * to process
88	 */
89	ath9k_hw_setuprxdesc(ah, ds,
90			     common->rx_bufsize,
91			     0);
92
93	if (sc->rx.rxlink == NULL)
94		ath9k_hw_putrxbuf(ah, bf->bf_daddr);
95	else
96		*sc->rx.rxlink = bf->bf_daddr;
97
98	sc->rx.rxlink = &ds->ds_link;
99	ath9k_hw_rxena(ah);
100}
101
102static void ath_setdefantenna(struct ath_softc *sc, u32 antenna)
103{
104	/* XXX block beacon interrupts */
105	ath9k_hw_setantenna(sc->sc_ah, antenna);
106	sc->rx.defant = antenna;
107	sc->rx.rxotherant = 0;
108}
109
110static void ath_opmode_init(struct ath_softc *sc)
111{
112	struct ath_hw *ah = sc->sc_ah;
113	struct ath_common *common = ath9k_hw_common(ah);
114
115	u32 rfilt, mfilt[2];
116
117	/* configure rx filter */
118	rfilt = ath_calcrxfilter(sc);
119	ath9k_hw_setrxfilter(ah, rfilt);
120
121	/* configure bssid mask */
122	ath_hw_setbssidmask(common);
123
124	/* configure operational mode */
125	ath9k_hw_setopmode(ah);
126
127	/* calculate and install multicast filter */
128	mfilt[0] = mfilt[1] = ~0;
129	ath9k_hw_setmcastfilter(ah, mfilt[0], mfilt[1]);
130}
131
132static bool ath_rx_edma_buf_link(struct ath_softc *sc,
133				 enum ath9k_rx_qtype qtype)
134{
135	struct ath_hw *ah = sc->sc_ah;
136	struct ath_rx_edma *rx_edma;
137	struct sk_buff *skb;
138	struct ath_buf *bf;
139
140	rx_edma = &sc->rx.rx_edma[qtype];
141	if (skb_queue_len(&rx_edma->rx_fifo) >= rx_edma->rx_fifo_hwsize)
142		return false;
143
144	bf = list_first_entry(&sc->rx.rxbuf, struct ath_buf, list);
145	list_del_init(&bf->list);
146
147	skb = bf->bf_mpdu;
148
149	ATH_RXBUF_RESET(bf);
150	memset(skb->data, 0, ah->caps.rx_status_len);
151	dma_sync_single_for_device(sc->dev, bf->bf_buf_addr,
152				ah->caps.rx_status_len, DMA_TO_DEVICE);
153
154	SKB_CB_ATHBUF(skb) = bf;
155	ath9k_hw_addrxbuf_edma(ah, bf->bf_buf_addr, qtype);
156	skb_queue_tail(&rx_edma->rx_fifo, skb);
157
158	return true;
159}
160
161static void ath_rx_addbuffer_edma(struct ath_softc *sc,
162				  enum ath9k_rx_qtype qtype, int size)
163{
164	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
165	u32 nbuf = 0;
166
167	if (list_empty(&sc->rx.rxbuf)) {
168		ath_print(common, ATH_DBG_QUEUE, "No free rx buf available\n");
169		return;
170	}
171
172	while (!list_empty(&sc->rx.rxbuf)) {
173		nbuf++;
174
175		if (!ath_rx_edma_buf_link(sc, qtype))
176			break;
177
178		if (nbuf >= size)
179			break;
180	}
181}
182
183static void ath_rx_remove_buffer(struct ath_softc *sc,
184				 enum ath9k_rx_qtype qtype)
185{
186	struct ath_buf *bf;
187	struct ath_rx_edma *rx_edma;
188	struct sk_buff *skb;
189
190	rx_edma = &sc->rx.rx_edma[qtype];
191
192	while ((skb = skb_dequeue(&rx_edma->rx_fifo)) != NULL) {
193		bf = SKB_CB_ATHBUF(skb);
194		BUG_ON(!bf);
195		list_add_tail(&bf->list, &sc->rx.rxbuf);
196	}
197}
198
199static void ath_rx_edma_cleanup(struct ath_softc *sc)
200{
201	struct ath_buf *bf;
202
203	ath_rx_remove_buffer(sc, ATH9K_RX_QUEUE_LP);
204	ath_rx_remove_buffer(sc, ATH9K_RX_QUEUE_HP);
205
206	list_for_each_entry(bf, &sc->rx.rxbuf, list) {
207		if (bf->bf_mpdu)
208			dev_kfree_skb_any(bf->bf_mpdu);
209	}
210
211	INIT_LIST_HEAD(&sc->rx.rxbuf);
212
213	kfree(sc->rx.rx_bufptr);
214	sc->rx.rx_bufptr = NULL;
215}
216
217static void ath_rx_edma_init_queue(struct ath_rx_edma *rx_edma, int size)
218{
219	skb_queue_head_init(&rx_edma->rx_fifo);
220	skb_queue_head_init(&rx_edma->rx_buffers);
221	rx_edma->rx_fifo_hwsize = size;
222}
223
224static int ath_rx_edma_init(struct ath_softc *sc, int nbufs)
225{
226	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
227	struct ath_hw *ah = sc->sc_ah;
228	struct sk_buff *skb;
229	struct ath_buf *bf;
230	int error = 0, i;
231	u32 size;
232
233
234	common->rx_bufsize = roundup(IEEE80211_MAX_MPDU_LEN +
235				     ah->caps.rx_status_len,
236				     min(common->cachelsz, (u16)64));
237
238	ath9k_hw_set_rx_bufsize(ah, common->rx_bufsize -
239				    ah->caps.rx_status_len);
240
241	ath_rx_edma_init_queue(&sc->rx.rx_edma[ATH9K_RX_QUEUE_LP],
242			       ah->caps.rx_lp_qdepth);
243	ath_rx_edma_init_queue(&sc->rx.rx_edma[ATH9K_RX_QUEUE_HP],
244			       ah->caps.rx_hp_qdepth);
245
246	size = sizeof(struct ath_buf) * nbufs;
247	bf = kzalloc(size, GFP_KERNEL);
248	if (!bf)
249		return -ENOMEM;
250
251	INIT_LIST_HEAD(&sc->rx.rxbuf);
252	sc->rx.rx_bufptr = bf;
253
254	for (i = 0; i < nbufs; i++, bf++) {
255		skb = ath_rxbuf_alloc(common, common->rx_bufsize, GFP_KERNEL);
256		if (!skb) {
257			error = -ENOMEM;
258			goto rx_init_fail;
259		}
260
261		memset(skb->data, 0, common->rx_bufsize);
262		bf->bf_mpdu = skb;
263
264		bf->bf_buf_addr = dma_map_single(sc->dev, skb->data,
265						 common->rx_bufsize,
266						 DMA_BIDIRECTIONAL);
267		if (unlikely(dma_mapping_error(sc->dev,
268						bf->bf_buf_addr))) {
269				dev_kfree_skb_any(skb);
270				bf->bf_mpdu = NULL;
271				ath_print(common, ATH_DBG_FATAL,
272					"dma_mapping_error() on RX init\n");
273				error = -ENOMEM;
274				goto rx_init_fail;
275		}
276
277		list_add_tail(&bf->list, &sc->rx.rxbuf);
278	}
279
280	return 0;
281
282rx_init_fail:
283	ath_rx_edma_cleanup(sc);
284	return error;
285}
286
287static void ath_edma_start_recv(struct ath_softc *sc)
288{
289	spin_lock_bh(&sc->rx.rxbuflock);
290
291	ath9k_hw_rxena(sc->sc_ah);
292
293	ath_rx_addbuffer_edma(sc, ATH9K_RX_QUEUE_HP,
294			      sc->rx.rx_edma[ATH9K_RX_QUEUE_HP].rx_fifo_hwsize);
295
296	ath_rx_addbuffer_edma(sc, ATH9K_RX_QUEUE_LP,
297			      sc->rx.rx_edma[ATH9K_RX_QUEUE_LP].rx_fifo_hwsize);
298
299	spin_unlock_bh(&sc->rx.rxbuflock);
300
301	ath_opmode_init(sc);
302
303	ath9k_hw_startpcureceive(sc->sc_ah, (sc->sc_flags & SC_OP_OFFCHANNEL));
304}
305
306static void ath_edma_stop_recv(struct ath_softc *sc)
307{
308	spin_lock_bh(&sc->rx.rxbuflock);
309	ath_rx_remove_buffer(sc, ATH9K_RX_QUEUE_HP);
310	ath_rx_remove_buffer(sc, ATH9K_RX_QUEUE_LP);
311	spin_unlock_bh(&sc->rx.rxbuflock);
312}
313
314int ath_rx_init(struct ath_softc *sc, int nbufs)
315{
316	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
317	struct sk_buff *skb;
318	struct ath_buf *bf;
319	int error = 0;
320
321	spin_lock_init(&sc->rx.rxflushlock);
322	sc->sc_flags &= ~SC_OP_RXFLUSH;
323	spin_lock_init(&sc->rx.rxbuflock);
324
325	if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) {
326		return ath_rx_edma_init(sc, nbufs);
327	} else {
328		common->rx_bufsize = roundup(IEEE80211_MAX_MPDU_LEN,
329				min(common->cachelsz, (u16)64));
330
331		ath_print(common, ATH_DBG_CONFIG, "cachelsz %u rxbufsize %u\n",
332				common->cachelsz, common->rx_bufsize);
333
334		/* Initialize rx descriptors */
335
336		error = ath_descdma_setup(sc, &sc->rx.rxdma, &sc->rx.rxbuf,
337				"rx", nbufs, 1, 0);
338		if (error != 0) {
339			ath_print(common, ATH_DBG_FATAL,
340				  "failed to allocate rx descriptors: %d\n",
341				  error);
342			goto err;
343		}
344
345		list_for_each_entry(bf, &sc->rx.rxbuf, list) {
346			skb = ath_rxbuf_alloc(common, common->rx_bufsize,
347					      GFP_KERNEL);
348			if (skb == NULL) {
349				error = -ENOMEM;
350				goto err;
351			}
352
353			bf->bf_mpdu = skb;
354			bf->bf_buf_addr = dma_map_single(sc->dev, skb->data,
355					common->rx_bufsize,
356					DMA_FROM_DEVICE);
357			if (unlikely(dma_mapping_error(sc->dev,
358							bf->bf_buf_addr))) {
359				dev_kfree_skb_any(skb);
360				bf->bf_mpdu = NULL;
361				ath_print(common, ATH_DBG_FATAL,
362					  "dma_mapping_error() on RX init\n");
363				error = -ENOMEM;
364				goto err;
365			}
366			bf->bf_dmacontext = bf->bf_buf_addr;
367		}
368		sc->rx.rxlink = NULL;
369	}
370
371err:
372	if (error)
373		ath_rx_cleanup(sc);
374
375	return error;
376}
377
378void ath_rx_cleanup(struct ath_softc *sc)
379{
380	struct ath_hw *ah = sc->sc_ah;
381	struct ath_common *common = ath9k_hw_common(ah);
382	struct sk_buff *skb;
383	struct ath_buf *bf;
384
385	if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) {
386		ath_rx_edma_cleanup(sc);
387		return;
388	} else {
389		list_for_each_entry(bf, &sc->rx.rxbuf, list) {
390			skb = bf->bf_mpdu;
391			if (skb) {
392				dma_unmap_single(sc->dev, bf->bf_buf_addr,
393						common->rx_bufsize,
394						DMA_FROM_DEVICE);
395				dev_kfree_skb(skb);
396			}
397		}
398
399		if (sc->rx.rxdma.dd_desc_len != 0)
400			ath_descdma_cleanup(sc, &sc->rx.rxdma, &sc->rx.rxbuf);
401	}
402}
403
404/*
405 * Calculate the receive filter according to the
406 * operating mode and state:
407 *
408 * o always accept unicast, broadcast, and multicast traffic
409 * o maintain current state of phy error reception (the hal
410 *   may enable phy error frames for noise immunity work)
411 * o probe request frames are accepted only when operating in
412 *   hostap, adhoc, or monitor modes
413 * o enable promiscuous mode according to the interface state
414 * o accept beacons:
415 *   - when operating in adhoc mode so the 802.11 layer creates
416 *     node table entries for peers,
417 *   - when operating in station mode for collecting rssi data when
418 *     the station is otherwise quiet, or
419 *   - when operating as a repeater so we see repeater-sta beacons
420 *   - when scanning
421 */
422
423u32 ath_calcrxfilter(struct ath_softc *sc)
424{
425#define	RX_FILTER_PRESERVE (ATH9K_RX_FILTER_PHYERR | ATH9K_RX_FILTER_PHYRADAR)
426
427	u32 rfilt;
428
429	rfilt = (ath9k_hw_getrxfilter(sc->sc_ah) & RX_FILTER_PRESERVE)
430		| ATH9K_RX_FILTER_UCAST | ATH9K_RX_FILTER_BCAST
431		| ATH9K_RX_FILTER_MCAST;
432
433	if (sc->rx.rxfilter & FIF_PROBE_REQ)
434		rfilt |= ATH9K_RX_FILTER_PROBEREQ;
435
436	/*
437	 * Set promiscuous mode when FIF_PROMISC_IN_BSS is enabled for station
438	 * mode interface or when in monitor mode. AP mode does not need this
439	 * since it receives all in-BSS frames anyway.
440	 */
441	if (((sc->sc_ah->opmode != NL80211_IFTYPE_AP) &&
442	     (sc->rx.rxfilter & FIF_PROMISC_IN_BSS)) ||
443	    (sc->sc_ah->opmode == NL80211_IFTYPE_MONITOR))
444		rfilt |= ATH9K_RX_FILTER_PROM;
445
446	if (sc->rx.rxfilter & FIF_CONTROL)
447		rfilt |= ATH9K_RX_FILTER_CONTROL;
448
449	if ((sc->sc_ah->opmode == NL80211_IFTYPE_STATION) &&
450	    (sc->nvifs <= 1) &&
451	    !(sc->rx.rxfilter & FIF_BCN_PRBRESP_PROMISC))
452		rfilt |= ATH9K_RX_FILTER_MYBEACON;
453	else
454		rfilt |= ATH9K_RX_FILTER_BEACON;
455
456	if ((AR_SREV_9280_20_OR_LATER(sc->sc_ah) ||
457	    AR_SREV_9285_12_OR_LATER(sc->sc_ah)) &&
458	    (sc->sc_ah->opmode == NL80211_IFTYPE_AP) &&
459	    (sc->rx.rxfilter & FIF_PSPOLL))
460		rfilt |= ATH9K_RX_FILTER_PSPOLL;
461
462	if (conf_is_ht(&sc->hw->conf))
463		rfilt |= ATH9K_RX_FILTER_COMP_BAR;
464
465	if (sc->sec_wiphy || (sc->nvifs > 1) ||
466	    (sc->rx.rxfilter & FIF_OTHER_BSS)) {
467		/* The following may also be needed for other older chips */
468		if (sc->sc_ah->hw_version.macVersion == AR_SREV_VERSION_9160)
469			rfilt |= ATH9K_RX_FILTER_PROM;
470		rfilt |= ATH9K_RX_FILTER_MCAST_BCAST_ALL;
471	}
472
473	return rfilt;
474
475#undef RX_FILTER_PRESERVE
476}
477
478int ath_startrecv(struct ath_softc *sc)
479{
480	struct ath_hw *ah = sc->sc_ah;
481	struct ath_buf *bf, *tbf;
482
483	if (ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) {
484		ath_edma_start_recv(sc);
485		return 0;
486	}
487
488	spin_lock_bh(&sc->rx.rxbuflock);
489	if (list_empty(&sc->rx.rxbuf))
490		goto start_recv;
491
492	sc->rx.rxlink = NULL;
493	list_for_each_entry_safe(bf, tbf, &sc->rx.rxbuf, list) {
494		ath_rx_buf_link(sc, bf);
495	}
496
497	/* We could have deleted elements so the list may be empty now */
498	if (list_empty(&sc->rx.rxbuf))
499		goto start_recv;
500
501	bf = list_first_entry(&sc->rx.rxbuf, struct ath_buf, list);
502	ath9k_hw_putrxbuf(ah, bf->bf_daddr);
503	ath9k_hw_rxena(ah);
504
505start_recv:
506	spin_unlock_bh(&sc->rx.rxbuflock);
507	ath_opmode_init(sc);
508	ath9k_hw_startpcureceive(ah, (sc->sc_flags & SC_OP_OFFCHANNEL));
509
510	return 0;
511}
512
513bool ath_stoprecv(struct ath_softc *sc)
514{
515	struct ath_hw *ah = sc->sc_ah;
516	bool stopped;
517
518	ath9k_hw_stoppcurecv(ah);
519	ath9k_hw_setrxfilter(ah, 0);
520	stopped = ath9k_hw_stopdmarecv(ah);
521
522	if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA)
523		ath_edma_stop_recv(sc);
524	else
525		sc->rx.rxlink = NULL;
526
527	return stopped;
528}
529
530void ath_flushrecv(struct ath_softc *sc)
531{
532	spin_lock_bh(&sc->rx.rxflushlock);
533	sc->sc_flags |= SC_OP_RXFLUSH;
534	if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA)
535		ath_rx_tasklet(sc, 1, true);
536	ath_rx_tasklet(sc, 1, false);
537	sc->sc_flags &= ~SC_OP_RXFLUSH;
538	spin_unlock_bh(&sc->rx.rxflushlock);
539}
540
541static bool ath_beacon_dtim_pending_cab(struct sk_buff *skb)
542{
543	/* Check whether the Beacon frame has DTIM indicating buffered bc/mc */
544	struct ieee80211_mgmt *mgmt;
545	u8 *pos, *end, id, elen;
546	struct ieee80211_tim_ie *tim;
547
548	mgmt = (struct ieee80211_mgmt *)skb->data;
549	pos = mgmt->u.beacon.variable;
550	end = skb->data + skb->len;
551
552	while (pos + 2 < end) {
553		id = *pos++;
554		elen = *pos++;
555		if (pos + elen > end)
556			break;
557
558		if (id == WLAN_EID_TIM) {
559			if (elen < sizeof(*tim))
560				break;
561			tim = (struct ieee80211_tim_ie *) pos;
562			if (tim->dtim_count != 0)
563				break;
564			return tim->bitmap_ctrl & 0x01;
565		}
566
567		pos += elen;
568	}
569
570	return false;
571}
572
573static void ath_rx_ps_beacon(struct ath_softc *sc, struct sk_buff *skb)
574{
575	struct ieee80211_mgmt *mgmt;
576	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
577
578	if (skb->len < 24 + 8 + 2 + 2)
579		return;
580
581	mgmt = (struct ieee80211_mgmt *)skb->data;
582	if (memcmp(common->curbssid, mgmt->bssid, ETH_ALEN) != 0)
583		return; /* not from our current AP */
584
585	sc->ps_flags &= ~PS_WAIT_FOR_BEACON;
586
587	if (sc->ps_flags & PS_BEACON_SYNC) {
588		sc->ps_flags &= ~PS_BEACON_SYNC;
589		ath_print(common, ATH_DBG_PS,
590			  "Reconfigure Beacon timers based on "
591			  "timestamp from the AP\n");
592		ath_beacon_config(sc, NULL);
593	}
594
595	if (ath_beacon_dtim_pending_cab(skb)) {
596		/*
597		 * Remain awake waiting for buffered broadcast/multicast
598		 * frames. If the last broadcast/multicast frame is not
599		 * received properly, the next beacon frame will work as
600		 * a backup trigger for returning into NETWORK SLEEP state,
601		 * so we are waiting for it as well.
602		 */
603		ath_print(common, ATH_DBG_PS, "Received DTIM beacon indicating "
604			  "buffered broadcast/multicast frame(s)\n");
605		sc->ps_flags |= PS_WAIT_FOR_CAB | PS_WAIT_FOR_BEACON;
606		return;
607	}
608
609	if (sc->ps_flags & PS_WAIT_FOR_CAB) {
610		/*
611		 * This can happen if a broadcast frame is dropped or the AP
612		 * fails to send a frame indicating that all CAB frames have
613		 * been delivered.
614		 */
615		sc->ps_flags &= ~PS_WAIT_FOR_CAB;
616		ath_print(common, ATH_DBG_PS,
617			  "PS wait for CAB frames timed out\n");
618	}
619}
620
621static void ath_rx_ps(struct ath_softc *sc, struct sk_buff *skb)
622{
623	struct ieee80211_hdr *hdr;
624	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
625
626	hdr = (struct ieee80211_hdr *)skb->data;
627
628	/* Process Beacon and CAB receive in PS state */
629	if (((sc->ps_flags & PS_WAIT_FOR_BEACON) || ath9k_check_auto_sleep(sc))
630	    && ieee80211_is_beacon(hdr->frame_control))
631		ath_rx_ps_beacon(sc, skb);
632	else if ((sc->ps_flags & PS_WAIT_FOR_CAB) &&
633		 (ieee80211_is_data(hdr->frame_control) ||
634		  ieee80211_is_action(hdr->frame_control)) &&
635		 is_multicast_ether_addr(hdr->addr1) &&
636		 !ieee80211_has_moredata(hdr->frame_control)) {
637		/*
638		 * No more broadcast/multicast frames to be received at this
639		 * point.
640		 */
641		sc->ps_flags &= ~(PS_WAIT_FOR_CAB | PS_WAIT_FOR_BEACON);
642		ath_print(common, ATH_DBG_PS,
643			  "All PS CAB frames received, back to sleep\n");
644	} else if ((sc->ps_flags & PS_WAIT_FOR_PSPOLL_DATA) &&
645		   !is_multicast_ether_addr(hdr->addr1) &&
646		   !ieee80211_has_morefrags(hdr->frame_control)) {
647		sc->ps_flags &= ~PS_WAIT_FOR_PSPOLL_DATA;
648		ath_print(common, ATH_DBG_PS,
649			  "Going back to sleep after having received "
650			  "PS-Poll data (0x%lx)\n",
651			sc->ps_flags & (PS_WAIT_FOR_BEACON |
652					PS_WAIT_FOR_CAB |
653					PS_WAIT_FOR_PSPOLL_DATA |
654					PS_WAIT_FOR_TX_ACK));
655	}
656}
657
658static void ath_rx_send_to_mac80211(struct ieee80211_hw *hw,
659				    struct ath_softc *sc, struct sk_buff *skb,
660				    struct ieee80211_rx_status *rxs)
661{
662	struct ieee80211_hdr *hdr;
663
664	hdr = (struct ieee80211_hdr *)skb->data;
665
666	/* Send the frame to mac80211 */
667	if (is_multicast_ether_addr(hdr->addr1)) {
668		int i;
669		/*
670		 * Deliver broadcast/multicast frames to all suitable
671		 * virtual wiphys.
672		 */
673		/* TODO: filter based on channel configuration */
674		for (i = 0; i < sc->num_sec_wiphy; i++) {
675			struct ath_wiphy *aphy = sc->sec_wiphy[i];
676			struct sk_buff *nskb;
677			if (aphy == NULL)
678				continue;
679			nskb = skb_copy(skb, GFP_ATOMIC);
680			if (!nskb)
681				continue;
682			ieee80211_rx(aphy->hw, nskb);
683		}
684		ieee80211_rx(sc->hw, skb);
685	} else
686		/* Deliver unicast frames based on receiver address */
687		ieee80211_rx(hw, skb);
688}
689
690static bool ath_edma_get_buffers(struct ath_softc *sc,
691				 enum ath9k_rx_qtype qtype)
692{
693	struct ath_rx_edma *rx_edma = &sc->rx.rx_edma[qtype];
694	struct ath_hw *ah = sc->sc_ah;
695	struct ath_common *common = ath9k_hw_common(ah);
696	struct sk_buff *skb;
697	struct ath_buf *bf;
698	int ret;
699
700	skb = skb_peek(&rx_edma->rx_fifo);
701	if (!skb)
702		return false;
703
704	bf = SKB_CB_ATHBUF(skb);
705	BUG_ON(!bf);
706
707	dma_sync_single_for_cpu(sc->dev, bf->bf_buf_addr,
708				common->rx_bufsize, DMA_FROM_DEVICE);
709
710	ret = ath9k_hw_process_rxdesc_edma(ah, NULL, skb->data);
711	if (ret == -EINPROGRESS) {
712		/*let device gain the buffer again*/
713		dma_sync_single_for_device(sc->dev, bf->bf_buf_addr,
714				common->rx_bufsize, DMA_FROM_DEVICE);
715		return false;
716	}
717
718	__skb_unlink(skb, &rx_edma->rx_fifo);
719	if (ret == -EINVAL) {
720		/* corrupt descriptor, skip this one and the following one */
721		list_add_tail(&bf->list, &sc->rx.rxbuf);
722		ath_rx_edma_buf_link(sc, qtype);
723		skb = skb_peek(&rx_edma->rx_fifo);
724		if (!skb)
725			return true;
726
727		bf = SKB_CB_ATHBUF(skb);
728		BUG_ON(!bf);
729
730		__skb_unlink(skb, &rx_edma->rx_fifo);
731		list_add_tail(&bf->list, &sc->rx.rxbuf);
732		ath_rx_edma_buf_link(sc, qtype);
733		return true;
734	}
735	skb_queue_tail(&rx_edma->rx_buffers, skb);
736
737	return true;
738}
739
740static struct ath_buf *ath_edma_get_next_rx_buf(struct ath_softc *sc,
741						struct ath_rx_status *rs,
742						enum ath9k_rx_qtype qtype)
743{
744	struct ath_rx_edma *rx_edma = &sc->rx.rx_edma[qtype];
745	struct sk_buff *skb;
746	struct ath_buf *bf;
747
748	while (ath_edma_get_buffers(sc, qtype));
749	skb = __skb_dequeue(&rx_edma->rx_buffers);
750	if (!skb)
751		return NULL;
752
753	bf = SKB_CB_ATHBUF(skb);
754	ath9k_hw_process_rxdesc_edma(sc->sc_ah, rs, skb->data);
755	return bf;
756}
757
758static struct ath_buf *ath_get_next_rx_buf(struct ath_softc *sc,
759					   struct ath_rx_status *rs)
760{
761	struct ath_hw *ah = sc->sc_ah;
762	struct ath_common *common = ath9k_hw_common(ah);
763	struct ath_desc *ds;
764	struct ath_buf *bf;
765	int ret;
766
767	if (list_empty(&sc->rx.rxbuf)) {
768		sc->rx.rxlink = NULL;
769		return NULL;
770	}
771
772	bf = list_first_entry(&sc->rx.rxbuf, struct ath_buf, list);
773	ds = bf->bf_desc;
774
775	/*
776	 * Must provide the virtual address of the current
777	 * descriptor, the physical address, and the virtual
778	 * address of the next descriptor in the h/w chain.
779	 * This allows the HAL to look ahead to see if the
780	 * hardware is done with a descriptor by checking the
781	 * done bit in the following descriptor and the address
782	 * of the current descriptor the DMA engine is working
783	 * on.  All this is necessary because of our use of
784	 * a self-linked list to avoid rx overruns.
785	 */
786	ret = ath9k_hw_rxprocdesc(ah, ds, rs, 0);
787	if (ret == -EINPROGRESS) {
788		struct ath_rx_status trs;
789		struct ath_buf *tbf;
790		struct ath_desc *tds;
791
792		memset(&trs, 0, sizeof(trs));
793		if (list_is_last(&bf->list, &sc->rx.rxbuf)) {
794			sc->rx.rxlink = NULL;
795			return NULL;
796		}
797
798		tbf = list_entry(bf->list.next, struct ath_buf, list);
799
800		/*
801		 * On some hardware the descriptor status words could
802		 * get corrupted, including the done bit. Because of
803		 * this, check if the next descriptor's done bit is
804		 * set or not.
805		 *
806		 * If the next descriptor's done bit is set, the current
807		 * descriptor has been corrupted. Force s/w to discard
808		 * this descriptor and continue...
809		 */
810
811		tds = tbf->bf_desc;
812		ret = ath9k_hw_rxprocdesc(ah, tds, &trs, 0);
813		if (ret == -EINPROGRESS)
814			return NULL;
815	}
816
817	if (!bf->bf_mpdu)
818		return bf;
819
820	/*
821	 * Synchronize the DMA transfer with CPU before
822	 * 1. accessing the frame
823	 * 2. requeueing the same buffer to h/w
824	 */
825	dma_sync_single_for_cpu(sc->dev, bf->bf_buf_addr,
826			common->rx_bufsize,
827			DMA_FROM_DEVICE);
828
829	return bf;
830}
831
832/* Assumes you've already done the endian to CPU conversion */
833static bool ath9k_rx_accept(struct ath_common *common,
834			    struct ieee80211_hdr *hdr,
835			    struct ieee80211_rx_status *rxs,
836			    struct ath_rx_status *rx_stats,
837			    bool *decrypt_error)
838{
839	struct ath_hw *ah = common->ah;
840	__le16 fc;
841	u8 rx_status_len = ah->caps.rx_status_len;
842
843	fc = hdr->frame_control;
844
845	if (!rx_stats->rs_datalen)
846		return false;
847        /*
848         * rs_status follows rs_datalen so if rs_datalen is too large
849         * we can take a hint that hardware corrupted it, so ignore
850         * those frames.
851         */
852	if (rx_stats->rs_datalen > (common->rx_bufsize - rx_status_len))
853		return false;
854
855	/*
856	 * rs_more indicates chained descriptors which can be used
857	 * to link buffers together for a sort of scatter-gather
858	 * operation.
859	 * reject the frame, we don't support scatter-gather yet and
860	 * the frame is probably corrupt anyway
861	 */
862	if (rx_stats->rs_more)
863		return false;
864
865	/*
866	 * The rx_stats->rs_status will not be set until the end of the
867	 * chained descriptors so it can be ignored if rs_more is set. The
868	 * rs_more will be false at the last element of the chained
869	 * descriptors.
870	 */
871	if (rx_stats->rs_status != 0) {
872		if (rx_stats->rs_status & ATH9K_RXERR_CRC)
873			rxs->flag |= RX_FLAG_FAILED_FCS_CRC;
874		if (rx_stats->rs_status & ATH9K_RXERR_PHY)
875			return false;
876
877		if (rx_stats->rs_status & ATH9K_RXERR_DECRYPT) {
878			*decrypt_error = true;
879		} else if (rx_stats->rs_status & ATH9K_RXERR_MIC) {
880			/*
881			 * The MIC error bit is only valid if the frame
882			 * is not a control frame or fragment, and it was
883			 * decrypted using a valid TKIP key.
884			 */
885			if (!ieee80211_is_ctl(fc) &&
886			    !ieee80211_has_morefrags(fc) &&
887			    !(le16_to_cpu(hdr->seq_ctrl) & IEEE80211_SCTL_FRAG) &&
888			    test_bit(rx_stats->rs_keyix, common->tkip_keymap))
889				rxs->flag |= RX_FLAG_MMIC_ERROR;
890			else
891				rx_stats->rs_status &= ~ATH9K_RXERR_MIC;
892		}
893		/*
894		 * Reject error frames with the exception of
895		 * decryption and MIC failures. For monitor mode,
896		 * we also ignore the CRC error.
897		 */
898		if (ah->opmode == NL80211_IFTYPE_MONITOR) {
899			if (rx_stats->rs_status &
900			    ~(ATH9K_RXERR_DECRYPT | ATH9K_RXERR_MIC |
901			      ATH9K_RXERR_CRC))
902				return false;
903		} else {
904			if (rx_stats->rs_status &
905			    ~(ATH9K_RXERR_DECRYPT | ATH9K_RXERR_MIC)) {
906				return false;
907			}
908		}
909	}
910	return true;
911}
912
913static int ath9k_process_rate(struct ath_common *common,
914			      struct ieee80211_hw *hw,
915			      struct ath_rx_status *rx_stats,
916			      struct ieee80211_rx_status *rxs)
917{
918	struct ieee80211_supported_band *sband;
919	enum ieee80211_band band;
920	unsigned int i = 0;
921
922	band = hw->conf.channel->band;
923	sband = hw->wiphy->bands[band];
924
925	if (rx_stats->rs_rate & 0x80) {
926		/* HT rate */
927		rxs->flag |= RX_FLAG_HT;
928		if (rx_stats->rs_flags & ATH9K_RX_2040)
929			rxs->flag |= RX_FLAG_40MHZ;
930		if (rx_stats->rs_flags & ATH9K_RX_GI)
931			rxs->flag |= RX_FLAG_SHORT_GI;
932		rxs->rate_idx = rx_stats->rs_rate & 0x7f;
933		return 0;
934	}
935
936	for (i = 0; i < sband->n_bitrates; i++) {
937		if (sband->bitrates[i].hw_value == rx_stats->rs_rate) {
938			rxs->rate_idx = i;
939			return 0;
940		}
941		if (sband->bitrates[i].hw_value_short == rx_stats->rs_rate) {
942			rxs->flag |= RX_FLAG_SHORTPRE;
943			rxs->rate_idx = i;
944			return 0;
945		}
946	}
947
948	/*
949	 * No valid hardware bitrate found -- we should not get here
950	 * because hardware has already validated this frame as OK.
951	 */
952	ath_print(common, ATH_DBG_XMIT, "unsupported hw bitrate detected "
953		  "0x%02x using 1 Mbit\n", rx_stats->rs_rate);
954
955	return -EINVAL;
956}
957
958static void ath9k_process_rssi(struct ath_common *common,
959			       struct ieee80211_hw *hw,
960			       struct ieee80211_hdr *hdr,
961			       struct ath_rx_status *rx_stats)
962{
963	struct ath_hw *ah = common->ah;
964	struct ieee80211_sta *sta;
965	struct ath_node *an;
966	int last_rssi = ATH_RSSI_DUMMY_MARKER;
967	__le16 fc;
968
969	fc = hdr->frame_control;
970
971	rcu_read_lock();
972	/*
973	 * XXX: use ieee80211_find_sta! This requires quite a bit of work
974	 * under the current ath9k virtual wiphy implementation as we have
975	 * no way of tying a vif to wiphy. Typically vifs are attached to
976	 * at least one sdata of a wiphy on mac80211 but with ath9k virtual
977	 * wiphy you'd have to iterate over every wiphy and each sdata.
978	 */
979	if (is_multicast_ether_addr(hdr->addr1))
980		sta = ieee80211_find_sta_by_ifaddr(hw, hdr->addr2, NULL);
981	else
982		sta = ieee80211_find_sta_by_ifaddr(hw, hdr->addr2, hdr->addr1);
983
984	if (sta) {
985		an = (struct ath_node *) sta->drv_priv;
986		if (rx_stats->rs_rssi != ATH9K_RSSI_BAD &&
987		   !rx_stats->rs_moreaggr)
988			ATH_RSSI_LPF(an->last_rssi, rx_stats->rs_rssi);
989		last_rssi = an->last_rssi;
990	}
991	rcu_read_unlock();
992
993	if (likely(last_rssi != ATH_RSSI_DUMMY_MARKER))
994		rx_stats->rs_rssi = ATH_EP_RND(last_rssi,
995					      ATH_RSSI_EP_MULTIPLIER);
996	if (rx_stats->rs_rssi < 0)
997		rx_stats->rs_rssi = 0;
998
999	/* Update Beacon RSSI, this is used by ANI. */
1000	if (ieee80211_is_beacon(fc))
1001		ah->stats.avgbrssi = rx_stats->rs_rssi;
1002}
1003
1004/*
1005 * For Decrypt or Demic errors, we only mark packet status here and always push
1006 * up the frame up to let mac80211 handle the actual error case, be it no
1007 * decryption key or real decryption error. This let us keep statistics there.
1008 */
1009static int ath9k_rx_skb_preprocess(struct ath_common *common,
1010				   struct ieee80211_hw *hw,
1011				   struct ieee80211_hdr *hdr,
1012				   struct ath_rx_status *rx_stats,
1013				   struct ieee80211_rx_status *rx_status,
1014				   bool *decrypt_error)
1015{
1016	memset(rx_status, 0, sizeof(struct ieee80211_rx_status));
1017
1018	/*
1019	 * everything but the rate is checked here, the rate check is done
1020	 * separately to avoid doing two lookups for a rate for each frame.
1021	 */
1022	if (!ath9k_rx_accept(common, hdr, rx_status, rx_stats, decrypt_error))
1023		return -EINVAL;
1024
1025	ath9k_process_rssi(common, hw, hdr, rx_stats);
1026
1027	if (ath9k_process_rate(common, hw, rx_stats, rx_status))
1028		return -EINVAL;
1029
1030	rx_status->band = hw->conf.channel->band;
1031	rx_status->freq = hw->conf.channel->center_freq;
1032	rx_status->signal = ATH_DEFAULT_NOISE_FLOOR + rx_stats->rs_rssi;
1033	rx_status->antenna = rx_stats->rs_antenna;
1034	rx_status->flag |= RX_FLAG_TSFT;
1035
1036	return 0;
1037}
1038
1039static void ath9k_rx_skb_postprocess(struct ath_common *common,
1040				     struct sk_buff *skb,
1041				     struct ath_rx_status *rx_stats,
1042				     struct ieee80211_rx_status *rxs,
1043				     bool decrypt_error)
1044{
1045	struct ath_hw *ah = common->ah;
1046	struct ieee80211_hdr *hdr;
1047	int hdrlen, padpos, padsize;
1048	u8 keyix;
1049	__le16 fc;
1050
1051	/* see if any padding is done by the hw and remove it */
1052	hdr = (struct ieee80211_hdr *) skb->data;
1053	hdrlen = ieee80211_get_hdrlen_from_skb(skb);
1054	fc = hdr->frame_control;
1055	padpos = ath9k_cmn_padpos(hdr->frame_control);
1056
1057	/* The MAC header is padded to have 32-bit boundary if the
1058	 * packet payload is non-zero. The general calculation for
1059	 * padsize would take into account odd header lengths:
1060	 * padsize = (4 - padpos % 4) % 4; However, since only
1061	 * even-length headers are used, padding can only be 0 or 2
1062	 * bytes and we can optimize this a bit. In addition, we must
1063	 * not try to remove padding from short control frames that do
1064	 * not have payload. */
1065	padsize = padpos & 3;
1066	if (padsize && skb->len>=padpos+padsize+FCS_LEN) {
1067		memmove(skb->data + padsize, skb->data, padpos);
1068		skb_pull(skb, padsize);
1069	}
1070
1071	keyix = rx_stats->rs_keyix;
1072
1073	if (!(keyix == ATH9K_RXKEYIX_INVALID) && !decrypt_error &&
1074	    ieee80211_has_protected(fc)) {
1075		rxs->flag |= RX_FLAG_DECRYPTED;
1076	} else if (ieee80211_has_protected(fc)
1077		   && !decrypt_error && skb->len >= hdrlen + 4) {
1078		keyix = skb->data[hdrlen + 3] >> 6;
1079
1080		if (test_bit(keyix, common->keymap))
1081			rxs->flag |= RX_FLAG_DECRYPTED;
1082	}
1083	if (ah->sw_mgmt_crypto &&
1084	    (rxs->flag & RX_FLAG_DECRYPTED) &&
1085	    ieee80211_is_mgmt(fc))
1086		/* Use software decrypt for management frames. */
1087		rxs->flag &= ~RX_FLAG_DECRYPTED;
1088}
1089
1090static void ath_lnaconf_alt_good_scan(struct ath_ant_comb *antcomb,
1091				      struct ath_hw_antcomb_conf ant_conf,
1092				      int main_rssi_avg)
1093{
1094	antcomb->quick_scan_cnt = 0;
1095
1096	if (ant_conf.main_lna_conf == ATH_ANT_DIV_COMB_LNA2)
1097		antcomb->rssi_lna2 = main_rssi_avg;
1098	else if (ant_conf.main_lna_conf == ATH_ANT_DIV_COMB_LNA1)
1099		antcomb->rssi_lna1 = main_rssi_avg;
1100
1101	switch ((ant_conf.main_lna_conf << 4) | ant_conf.alt_lna_conf) {
1102	case (0x10): /* LNA2 A-B */
1103		antcomb->main_conf = ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
1104		antcomb->first_quick_scan_conf =
1105			ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
1106		antcomb->second_quick_scan_conf = ATH_ANT_DIV_COMB_LNA1;
1107		break;
1108	case (0x20): /* LNA1 A-B */
1109		antcomb->main_conf = ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
1110		antcomb->first_quick_scan_conf =
1111			ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
1112		antcomb->second_quick_scan_conf = ATH_ANT_DIV_COMB_LNA2;
1113		break;
1114	case (0x21): /* LNA1 LNA2 */
1115		antcomb->main_conf = ATH_ANT_DIV_COMB_LNA2;
1116		antcomb->first_quick_scan_conf =
1117			ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
1118		antcomb->second_quick_scan_conf =
1119			ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
1120		break;
1121	case (0x12): /* LNA2 LNA1 */
1122		antcomb->main_conf = ATH_ANT_DIV_COMB_LNA1;
1123		antcomb->first_quick_scan_conf =
1124			ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
1125		antcomb->second_quick_scan_conf =
1126			ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
1127		break;
1128	case (0x13): /* LNA2 A+B */
1129		antcomb->main_conf = ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
1130		antcomb->first_quick_scan_conf =
1131			ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
1132		antcomb->second_quick_scan_conf = ATH_ANT_DIV_COMB_LNA1;
1133		break;
1134	case (0x23): /* LNA1 A+B */
1135		antcomb->main_conf = ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
1136		antcomb->first_quick_scan_conf =
1137			ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
1138		antcomb->second_quick_scan_conf = ATH_ANT_DIV_COMB_LNA2;
1139		break;
1140	default:
1141		break;
1142	}
1143}
1144
1145static void ath_select_ant_div_from_quick_scan(struct ath_ant_comb *antcomb,
1146				struct ath_hw_antcomb_conf *div_ant_conf,
1147				int main_rssi_avg, int alt_rssi_avg,
1148				int alt_ratio)
1149{
1150	/* alt_good */
1151	switch (antcomb->quick_scan_cnt) {
1152	case 0:
1153		/* set alt to main, and alt to first conf */
1154		div_ant_conf->main_lna_conf = antcomb->main_conf;
1155		div_ant_conf->alt_lna_conf = antcomb->first_quick_scan_conf;
1156		break;
1157	case 1:
1158		/* set alt to main, and alt to first conf */
1159		div_ant_conf->main_lna_conf = antcomb->main_conf;
1160		div_ant_conf->alt_lna_conf = antcomb->second_quick_scan_conf;
1161		antcomb->rssi_first = main_rssi_avg;
1162		antcomb->rssi_second = alt_rssi_avg;
1163
1164		if (antcomb->main_conf == ATH_ANT_DIV_COMB_LNA1) {
1165			/* main is LNA1 */
1166			if (ath_is_alt_ant_ratio_better(alt_ratio,
1167						ATH_ANT_DIV_COMB_LNA1_DELTA_HI,
1168						ATH_ANT_DIV_COMB_LNA1_DELTA_LOW,
1169						main_rssi_avg, alt_rssi_avg,
1170						antcomb->total_pkt_count))
1171				antcomb->first_ratio = true;
1172			else
1173				antcomb->first_ratio = false;
1174		} else if (antcomb->main_conf == ATH_ANT_DIV_COMB_LNA2) {
1175			if (ath_is_alt_ant_ratio_better(alt_ratio,
1176						ATH_ANT_DIV_COMB_LNA1_DELTA_MID,
1177						ATH_ANT_DIV_COMB_LNA1_DELTA_LOW,
1178						main_rssi_avg, alt_rssi_avg,
1179						antcomb->total_pkt_count))
1180				antcomb->first_ratio = true;
1181			else
1182				antcomb->first_ratio = false;
1183		} else {
1184			if ((((alt_ratio >= ATH_ANT_DIV_COMB_ALT_ANT_RATIO2) &&
1185			    (alt_rssi_avg > main_rssi_avg +
1186			    ATH_ANT_DIV_COMB_LNA1_DELTA_HI)) ||
1187			    (alt_rssi_avg > main_rssi_avg)) &&
1188			    (antcomb->total_pkt_count > 50))
1189				antcomb->first_ratio = true;
1190			else
1191				antcomb->first_ratio = false;
1192		}
1193		break;
1194	case 2:
1195		antcomb->alt_good = false;
1196		antcomb->scan_not_start = false;
1197		antcomb->scan = false;
1198		antcomb->rssi_first = main_rssi_avg;
1199		antcomb->rssi_third = alt_rssi_avg;
1200
1201		if (antcomb->second_quick_scan_conf == ATH_ANT_DIV_COMB_LNA1)
1202			antcomb->rssi_lna1 = alt_rssi_avg;
1203		else if (antcomb->second_quick_scan_conf ==
1204			 ATH_ANT_DIV_COMB_LNA2)
1205			antcomb->rssi_lna2 = alt_rssi_avg;
1206		else if (antcomb->second_quick_scan_conf ==
1207			 ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2) {
1208			if (antcomb->main_conf == ATH_ANT_DIV_COMB_LNA2)
1209				antcomb->rssi_lna2 = main_rssi_avg;
1210			else if (antcomb->main_conf == ATH_ANT_DIV_COMB_LNA1)
1211				antcomb->rssi_lna1 = main_rssi_avg;
1212		}
1213
1214		if (antcomb->rssi_lna2 > antcomb->rssi_lna1 +
1215		    ATH_ANT_DIV_COMB_LNA1_LNA2_SWITCH_DELTA)
1216			div_ant_conf->main_lna_conf = ATH_ANT_DIV_COMB_LNA2;
1217		else
1218			div_ant_conf->main_lna_conf = ATH_ANT_DIV_COMB_LNA1;
1219
1220		if (antcomb->main_conf == ATH_ANT_DIV_COMB_LNA1) {
1221			if (ath_is_alt_ant_ratio_better(alt_ratio,
1222						ATH_ANT_DIV_COMB_LNA1_DELTA_HI,
1223						ATH_ANT_DIV_COMB_LNA1_DELTA_LOW,
1224						main_rssi_avg, alt_rssi_avg,
1225						antcomb->total_pkt_count))
1226				antcomb->second_ratio = true;
1227			else
1228				antcomb->second_ratio = false;
1229		} else if (antcomb->main_conf == ATH_ANT_DIV_COMB_LNA2) {
1230			if (ath_is_alt_ant_ratio_better(alt_ratio,
1231						ATH_ANT_DIV_COMB_LNA1_DELTA_MID,
1232						ATH_ANT_DIV_COMB_LNA1_DELTA_LOW,
1233						main_rssi_avg, alt_rssi_avg,
1234						antcomb->total_pkt_count))
1235				antcomb->second_ratio = true;
1236			else
1237				antcomb->second_ratio = false;
1238		} else {
1239			if ((((alt_ratio >= ATH_ANT_DIV_COMB_ALT_ANT_RATIO2) &&
1240			    (alt_rssi_avg > main_rssi_avg +
1241			    ATH_ANT_DIV_COMB_LNA1_DELTA_HI)) ||
1242			    (alt_rssi_avg > main_rssi_avg)) &&
1243			    (antcomb->total_pkt_count > 50))
1244				antcomb->second_ratio = true;
1245			else
1246				antcomb->second_ratio = false;
1247		}
1248
1249		/* set alt to the conf with maximun ratio */
1250		if (antcomb->first_ratio && antcomb->second_ratio) {
1251			if (antcomb->rssi_second > antcomb->rssi_third) {
1252				/* first alt*/
1253				if ((antcomb->first_quick_scan_conf ==
1254				    ATH_ANT_DIV_COMB_LNA1) ||
1255				    (antcomb->first_quick_scan_conf ==
1256				    ATH_ANT_DIV_COMB_LNA2))
1257					/* Set alt LNA1 or LNA2*/
1258					if (div_ant_conf->main_lna_conf ==
1259					    ATH_ANT_DIV_COMB_LNA2)
1260						div_ant_conf->alt_lna_conf =
1261							ATH_ANT_DIV_COMB_LNA1;
1262					else
1263						div_ant_conf->alt_lna_conf =
1264							ATH_ANT_DIV_COMB_LNA2;
1265				else
1266					/* Set alt to A+B or A-B */
1267					div_ant_conf->alt_lna_conf =
1268						antcomb->first_quick_scan_conf;
1269			} else if ((antcomb->second_quick_scan_conf ==
1270				   ATH_ANT_DIV_COMB_LNA1) ||
1271				   (antcomb->second_quick_scan_conf ==
1272				   ATH_ANT_DIV_COMB_LNA2)) {
1273				/* Set alt LNA1 or LNA2 */
1274				if (div_ant_conf->main_lna_conf ==
1275				    ATH_ANT_DIV_COMB_LNA2)
1276					div_ant_conf->alt_lna_conf =
1277						ATH_ANT_DIV_COMB_LNA1;
1278				else
1279					div_ant_conf->alt_lna_conf =
1280						ATH_ANT_DIV_COMB_LNA2;
1281			} else {
1282				/* Set alt to A+B or A-B */
1283				div_ant_conf->alt_lna_conf =
1284					antcomb->second_quick_scan_conf;
1285			}
1286		} else if (antcomb->first_ratio) {
1287			/* first alt */
1288			if ((antcomb->first_quick_scan_conf ==
1289			    ATH_ANT_DIV_COMB_LNA1) ||
1290			    (antcomb->first_quick_scan_conf ==
1291			    ATH_ANT_DIV_COMB_LNA2))
1292					/* Set alt LNA1 or LNA2 */
1293				if (div_ant_conf->main_lna_conf ==
1294				    ATH_ANT_DIV_COMB_LNA2)
1295					div_ant_conf->alt_lna_conf =
1296							ATH_ANT_DIV_COMB_LNA1;
1297				else
1298					div_ant_conf->alt_lna_conf =
1299							ATH_ANT_DIV_COMB_LNA2;
1300			else
1301				/* Set alt to A+B or A-B */
1302				div_ant_conf->alt_lna_conf =
1303						antcomb->first_quick_scan_conf;
1304		} else if (antcomb->second_ratio) {
1305				/* second alt */
1306			if ((antcomb->second_quick_scan_conf ==
1307			    ATH_ANT_DIV_COMB_LNA1) ||
1308			    (antcomb->second_quick_scan_conf ==
1309			    ATH_ANT_DIV_COMB_LNA2))
1310				/* Set alt LNA1 or LNA2 */
1311				if (div_ant_conf->main_lna_conf ==
1312				    ATH_ANT_DIV_COMB_LNA2)
1313					div_ant_conf->alt_lna_conf =
1314						ATH_ANT_DIV_COMB_LNA1;
1315				else
1316					div_ant_conf->alt_lna_conf =
1317						ATH_ANT_DIV_COMB_LNA2;
1318			else
1319				/* Set alt to A+B or A-B */
1320				div_ant_conf->alt_lna_conf =
1321						antcomb->second_quick_scan_conf;
1322		} else {
1323			/* main is largest */
1324			if ((antcomb->main_conf == ATH_ANT_DIV_COMB_LNA1) ||
1325			    (antcomb->main_conf == ATH_ANT_DIV_COMB_LNA2))
1326				/* Set alt LNA1 or LNA2 */
1327				if (div_ant_conf->main_lna_conf ==
1328				    ATH_ANT_DIV_COMB_LNA2)
1329					div_ant_conf->alt_lna_conf =
1330							ATH_ANT_DIV_COMB_LNA1;
1331				else
1332					div_ant_conf->alt_lna_conf =
1333							ATH_ANT_DIV_COMB_LNA2;
1334			else
1335				/* Set alt to A+B or A-B */
1336				div_ant_conf->alt_lna_conf = antcomb->main_conf;
1337		}
1338		break;
1339	default:
1340		break;
1341	}
1342}
1343
1344static void ath_ant_div_conf_fast_divbias(struct ath_hw_antcomb_conf *ant_conf)
1345{
1346	/* Adjust the fast_div_bias based on main and alt lna conf */
1347	switch ((ant_conf->main_lna_conf << 4) | ant_conf->alt_lna_conf) {
1348	case (0x01): /* A-B LNA2 */
1349		ant_conf->fast_div_bias = 0x3b;
1350		break;
1351	case (0x02): /* A-B LNA1 */
1352		ant_conf->fast_div_bias = 0x3d;
1353		break;
1354	case (0x03): /* A-B A+B */
1355		ant_conf->fast_div_bias = 0x1;
1356		break;
1357	case (0x10): /* LNA2 A-B */
1358		ant_conf->fast_div_bias = 0x7;
1359		break;
1360	case (0x12): /* LNA2 LNA1 */
1361		ant_conf->fast_div_bias = 0x2;
1362		break;
1363	case (0x13): /* LNA2 A+B */
1364		ant_conf->fast_div_bias = 0x7;
1365		break;
1366	case (0x20): /* LNA1 A-B */
1367		ant_conf->fast_div_bias = 0x6;
1368		break;
1369	case (0x21): /* LNA1 LNA2 */
1370		ant_conf->fast_div_bias = 0x0;
1371		break;
1372	case (0x23): /* LNA1 A+B */
1373		ant_conf->fast_div_bias = 0x6;
1374		break;
1375	case (0x30): /* A+B A-B */
1376		ant_conf->fast_div_bias = 0x1;
1377		break;
1378	case (0x31): /* A+B LNA2 */
1379		ant_conf->fast_div_bias = 0x3b;
1380		break;
1381	case (0x32): /* A+B LNA1 */
1382		ant_conf->fast_div_bias = 0x3d;
1383		break;
1384	default:
1385		break;
1386	}
1387}
1388
1389/* Antenna diversity and combining */
1390static void ath_ant_comb_scan(struct ath_softc *sc, struct ath_rx_status *rs)
1391{
1392	struct ath_hw_antcomb_conf div_ant_conf;
1393	struct ath_ant_comb *antcomb = &sc->ant_comb;
1394	int alt_ratio = 0, alt_rssi_avg = 0, main_rssi_avg = 0, curr_alt_set;
1395	int curr_main_set, curr_bias;
1396	int main_rssi = rs->rs_rssi_ctl0;
1397	int alt_rssi = rs->rs_rssi_ctl1;
1398	int rx_ant_conf,  main_ant_conf;
1399	bool short_scan = false;
1400
1401	rx_ant_conf = (rs->rs_rssi_ctl2 >> ATH_ANT_RX_CURRENT_SHIFT) &
1402		       ATH_ANT_RX_MASK;
1403	main_ant_conf = (rs->rs_rssi_ctl2 >> ATH_ANT_RX_MAIN_SHIFT) &
1404			 ATH_ANT_RX_MASK;
1405
1406	/* Record packet only when alt_rssi is positive */
1407	if (alt_rssi > 0) {
1408		antcomb->total_pkt_count++;
1409		antcomb->main_total_rssi += main_rssi;
1410		antcomb->alt_total_rssi  += alt_rssi;
1411		if (main_ant_conf == rx_ant_conf)
1412			antcomb->main_recv_cnt++;
1413		else
1414			antcomb->alt_recv_cnt++;
1415	}
1416
1417	/* Short scan check */
1418	if (antcomb->scan && antcomb->alt_good) {
1419		if (time_after(jiffies, antcomb->scan_start_time +
1420		    msecs_to_jiffies(ATH_ANT_DIV_COMB_SHORT_SCAN_INTR)))
1421			short_scan = true;
1422		else
1423			if (antcomb->total_pkt_count ==
1424			    ATH_ANT_DIV_COMB_SHORT_SCAN_PKTCOUNT) {
1425				alt_ratio = ((antcomb->alt_recv_cnt * 100) /
1426					    antcomb->total_pkt_count);
1427				if (alt_ratio < ATH_ANT_DIV_COMB_ALT_ANT_RATIO)
1428					short_scan = true;
1429			}
1430	}
1431
1432	if (((antcomb->total_pkt_count < ATH_ANT_DIV_COMB_MAX_PKTCOUNT) ||
1433	    rs->rs_moreaggr) && !short_scan)
1434		return;
1435
1436	if (antcomb->total_pkt_count) {
1437		alt_ratio = ((antcomb->alt_recv_cnt * 100) /
1438			     antcomb->total_pkt_count);
1439		main_rssi_avg = (antcomb->main_total_rssi /
1440				 antcomb->total_pkt_count);
1441		alt_rssi_avg = (antcomb->alt_total_rssi /
1442				 antcomb->total_pkt_count);
1443	}
1444
1445
1446	ath9k_hw_antdiv_comb_conf_get(sc->sc_ah, &div_ant_conf);
1447	curr_alt_set = div_ant_conf.alt_lna_conf;
1448	curr_main_set = div_ant_conf.main_lna_conf;
1449	curr_bias = div_ant_conf.fast_div_bias;
1450
1451	antcomb->count++;
1452
1453	if (antcomb->count == ATH_ANT_DIV_COMB_MAX_COUNT) {
1454		if (alt_ratio > ATH_ANT_DIV_COMB_ALT_ANT_RATIO) {
1455			ath_lnaconf_alt_good_scan(antcomb, div_ant_conf,
1456						  main_rssi_avg);
1457			antcomb->alt_good = true;
1458		} else {
1459			antcomb->alt_good = false;
1460		}
1461
1462		antcomb->count = 0;
1463		antcomb->scan = true;
1464		antcomb->scan_not_start = true;
1465	}
1466
1467	if (!antcomb->scan) {
1468		if (alt_ratio > ATH_ANT_DIV_COMB_ALT_ANT_RATIO) {
1469			if (curr_alt_set == ATH_ANT_DIV_COMB_LNA2) {
1470				/* Switch main and alt LNA */
1471				div_ant_conf.main_lna_conf =
1472						ATH_ANT_DIV_COMB_LNA2;
1473				div_ant_conf.alt_lna_conf  =
1474						ATH_ANT_DIV_COMB_LNA1;
1475			} else if (curr_alt_set == ATH_ANT_DIV_COMB_LNA1) {
1476				div_ant_conf.main_lna_conf =
1477						ATH_ANT_DIV_COMB_LNA1;
1478				div_ant_conf.alt_lna_conf  =
1479						ATH_ANT_DIV_COMB_LNA2;
1480			}
1481
1482			goto div_comb_done;
1483		} else if ((curr_alt_set != ATH_ANT_DIV_COMB_LNA1) &&
1484			   (curr_alt_set != ATH_ANT_DIV_COMB_LNA2)) {
1485			/* Set alt to another LNA */
1486			if (curr_main_set == ATH_ANT_DIV_COMB_LNA2)
1487				div_ant_conf.alt_lna_conf =
1488						ATH_ANT_DIV_COMB_LNA1;
1489			else if (curr_main_set == ATH_ANT_DIV_COMB_LNA1)
1490				div_ant_conf.alt_lna_conf =
1491						ATH_ANT_DIV_COMB_LNA2;
1492
1493			goto div_comb_done;
1494		}
1495
1496		if ((alt_rssi_avg < (main_rssi_avg +
1497		    ATH_ANT_DIV_COMB_LNA1_LNA2_DELTA)))
1498			goto div_comb_done;
1499	}
1500
1501	if (!antcomb->scan_not_start) {
1502		switch (curr_alt_set) {
1503		case ATH_ANT_DIV_COMB_LNA2:
1504			antcomb->rssi_lna2 = alt_rssi_avg;
1505			antcomb->rssi_lna1 = main_rssi_avg;
1506			antcomb->scan = true;
1507			/* set to A+B */
1508			div_ant_conf.main_lna_conf =
1509				ATH_ANT_DIV_COMB_LNA1;
1510			div_ant_conf.alt_lna_conf  =
1511				ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
1512			break;
1513		case ATH_ANT_DIV_COMB_LNA1:
1514			antcomb->rssi_lna1 = alt_rssi_avg;
1515			antcomb->rssi_lna2 = main_rssi_avg;
1516			antcomb->scan = true;
1517			/* set to A+B */
1518			div_ant_conf.main_lna_conf = ATH_ANT_DIV_COMB_LNA2;
1519			div_ant_conf.alt_lna_conf  =
1520				ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
1521			break;
1522		case ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2:
1523			antcomb->rssi_add = alt_rssi_avg;
1524			antcomb->scan = true;
1525			/* set to A-B */
1526			div_ant_conf.alt_lna_conf =
1527				ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
1528			break;
1529		case ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2:
1530			antcomb->rssi_sub = alt_rssi_avg;
1531			antcomb->scan = false;
1532			if (antcomb->rssi_lna2 >
1533			    (antcomb->rssi_lna1 +
1534			    ATH_ANT_DIV_COMB_LNA1_LNA2_SWITCH_DELTA)) {
1535				/* use LNA2 as main LNA */
1536				if ((antcomb->rssi_add > antcomb->rssi_lna1) &&
1537				    (antcomb->rssi_add > antcomb->rssi_sub)) {
1538					/* set to A+B */
1539					div_ant_conf.main_lna_conf =
1540						ATH_ANT_DIV_COMB_LNA2;
1541					div_ant_conf.alt_lna_conf  =
1542						ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
1543				} else if (antcomb->rssi_sub >
1544					   antcomb->rssi_lna1) {
1545					/* set to A-B */
1546					div_ant_conf.main_lna_conf =
1547						ATH_ANT_DIV_COMB_LNA2;
1548					div_ant_conf.alt_lna_conf =
1549						ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
1550				} else {
1551					/* set to LNA1 */
1552					div_ant_conf.main_lna_conf =
1553						ATH_ANT_DIV_COMB_LNA2;
1554					div_ant_conf.alt_lna_conf =
1555						ATH_ANT_DIV_COMB_LNA1;
1556				}
1557			} else {
1558				/* use LNA1 as main LNA */
1559				if ((antcomb->rssi_add > antcomb->rssi_lna2) &&
1560				    (antcomb->rssi_add > antcomb->rssi_sub)) {
1561					/* set to A+B */
1562					div_ant_conf.main_lna_conf =
1563						ATH_ANT_DIV_COMB_LNA1;
1564					div_ant_conf.alt_lna_conf  =
1565						ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
1566				} else if (antcomb->rssi_sub >
1567					   antcomb->rssi_lna1) {
1568					/* set to A-B */
1569					div_ant_conf.main_lna_conf =
1570						ATH_ANT_DIV_COMB_LNA1;
1571					div_ant_conf.alt_lna_conf =
1572						ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
1573				} else {
1574					/* set to LNA2 */
1575					div_ant_conf.main_lna_conf =
1576						ATH_ANT_DIV_COMB_LNA1;
1577					div_ant_conf.alt_lna_conf =
1578						ATH_ANT_DIV_COMB_LNA2;
1579				}
1580			}
1581			break;
1582		default:
1583			break;
1584		}
1585	} else {
1586		if (!antcomb->alt_good) {
1587			antcomb->scan_not_start = false;
1588			/* Set alt to another LNA */
1589			if (curr_main_set == ATH_ANT_DIV_COMB_LNA2) {
1590				div_ant_conf.main_lna_conf =
1591						ATH_ANT_DIV_COMB_LNA2;
1592				div_ant_conf.alt_lna_conf =
1593						ATH_ANT_DIV_COMB_LNA1;
1594			} else if (curr_main_set == ATH_ANT_DIV_COMB_LNA1) {
1595				div_ant_conf.main_lna_conf =
1596						ATH_ANT_DIV_COMB_LNA1;
1597				div_ant_conf.alt_lna_conf =
1598						ATH_ANT_DIV_COMB_LNA2;
1599			}
1600			goto div_comb_done;
1601		}
1602	}
1603
1604	ath_select_ant_div_from_quick_scan(antcomb, &div_ant_conf,
1605					   main_rssi_avg, alt_rssi_avg,
1606					   alt_ratio);
1607
1608	antcomb->quick_scan_cnt++;
1609
1610div_comb_done:
1611	ath_ant_div_conf_fast_divbias(&div_ant_conf);
1612
1613	ath9k_hw_antdiv_comb_conf_set(sc->sc_ah, &div_ant_conf);
1614
1615	antcomb->scan_start_time = jiffies;
1616	antcomb->total_pkt_count = 0;
1617	antcomb->main_total_rssi = 0;
1618	antcomb->alt_total_rssi = 0;
1619	antcomb->main_recv_cnt = 0;
1620	antcomb->alt_recv_cnt = 0;
1621}
1622
1623int ath_rx_tasklet(struct ath_softc *sc, int flush, bool hp)
1624{
1625	struct ath_buf *bf;
1626	struct sk_buff *skb = NULL, *requeue_skb;
1627	struct ieee80211_rx_status *rxs;
1628	struct ath_hw *ah = sc->sc_ah;
1629	struct ath_common *common = ath9k_hw_common(ah);
1630	/*
1631	 * The hw can techncically differ from common->hw when using ath9k
1632	 * virtual wiphy so to account for that we iterate over the active
1633	 * wiphys and find the appropriate wiphy and therefore hw.
1634	 */
1635	struct ieee80211_hw *hw = NULL;
1636	struct ieee80211_hdr *hdr;
1637	int retval;
1638	bool decrypt_error = false;
1639	struct ath_rx_status rs;
1640	enum ath9k_rx_qtype qtype;
1641	bool edma = !!(ah->caps.hw_caps & ATH9K_HW_CAP_EDMA);
1642	int dma_type;
1643	u8 rx_status_len = ah->caps.rx_status_len;
1644	u64 tsf = 0;
1645	u32 tsf_lower = 0;
1646	unsigned long flags;
1647
1648	if (edma)
1649		dma_type = DMA_BIDIRECTIONAL;
1650	else
1651		dma_type = DMA_FROM_DEVICE;
1652
1653	qtype = hp ? ATH9K_RX_QUEUE_HP : ATH9K_RX_QUEUE_LP;
1654	spin_lock_bh(&sc->rx.rxbuflock);
1655
1656	tsf = ath9k_hw_gettsf64(ah);
1657	tsf_lower = tsf & 0xffffffff;
1658
1659	do {
1660		/* If handling rx interrupt and flush is in progress => exit */
1661		if ((sc->sc_flags & SC_OP_RXFLUSH) && (flush == 0))
1662			break;
1663
1664		memset(&rs, 0, sizeof(rs));
1665		if (edma)
1666			bf = ath_edma_get_next_rx_buf(sc, &rs, qtype);
1667		else
1668			bf = ath_get_next_rx_buf(sc, &rs);
1669
1670		if (!bf)
1671			break;
1672
1673		skb = bf->bf_mpdu;
1674		if (!skb)
1675			continue;
1676
1677		hdr = (struct ieee80211_hdr *) (skb->data + rx_status_len);
1678		rxs =  IEEE80211_SKB_RXCB(skb);
1679
1680		hw = ath_get_virt_hw(sc, hdr);
1681
1682		ath_debug_stat_rx(sc, &rs);
1683
1684		/*
1685		 * If we're asked to flush receive queue, directly
1686		 * chain it back at the queue without processing it.
1687		 */
1688		if (flush)
1689			goto requeue;
1690
1691		retval = ath9k_rx_skb_preprocess(common, hw, hdr, &rs,
1692						 rxs, &decrypt_error);
1693		if (retval)
1694			goto requeue;
1695
1696		rxs->mactime = (tsf & ~0xffffffffULL) | rs.rs_tstamp;
1697		if (rs.rs_tstamp > tsf_lower &&
1698		    unlikely(rs.rs_tstamp - tsf_lower > 0x10000000))
1699			rxs->mactime -= 0x100000000ULL;
1700
1701		if (rs.rs_tstamp < tsf_lower &&
1702		    unlikely(tsf_lower - rs.rs_tstamp > 0x10000000))
1703			rxs->mactime += 0x100000000ULL;
1704
1705		/* Ensure we always have an skb to requeue once we are done
1706		 * processing the current buffer's skb */
1707		requeue_skb = ath_rxbuf_alloc(common, common->rx_bufsize, GFP_ATOMIC);
1708
1709		/* If there is no memory we ignore the current RX'd frame,
1710		 * tell hardware it can give us a new frame using the old
1711		 * skb and put it at the tail of the sc->rx.rxbuf list for
1712		 * processing. */
1713		if (!requeue_skb)
1714			goto requeue;
1715
1716		/* Unmap the frame */
1717		dma_unmap_single(sc->dev, bf->bf_buf_addr,
1718				 common->rx_bufsize,
1719				 dma_type);
1720
1721		skb_put(skb, rs.rs_datalen + ah->caps.rx_status_len);
1722		if (ah->caps.rx_status_len)
1723			skb_pull(skb, ah->caps.rx_status_len);
1724
1725		ath9k_rx_skb_postprocess(common, skb, &rs,
1726					 rxs, decrypt_error);
1727
1728		/* We will now give hardware our shiny new allocated skb */
1729		bf->bf_mpdu = requeue_skb;
1730		bf->bf_buf_addr = dma_map_single(sc->dev, requeue_skb->data,
1731						 common->rx_bufsize,
1732						 dma_type);
1733		if (unlikely(dma_mapping_error(sc->dev,
1734			  bf->bf_buf_addr))) {
1735			dev_kfree_skb_any(requeue_skb);
1736			bf->bf_mpdu = NULL;
1737			ath_print(common, ATH_DBG_FATAL,
1738				  "dma_mapping_error() on RX\n");
1739			ath_rx_send_to_mac80211(hw, sc, skb, rxs);
1740			break;
1741		}
1742		bf->bf_dmacontext = bf->bf_buf_addr;
1743
1744		/*
1745		 * change the default rx antenna if rx diversity chooses the
1746		 * other antenna 3 times in a row.
1747		 */
1748		if (sc->rx.defant != rs.rs_antenna) {
1749			if (++sc->rx.rxotherant >= 3)
1750				ath_setdefantenna(sc, rs.rs_antenna);
1751		} else {
1752			sc->rx.rxotherant = 0;
1753		}
1754
1755		spin_lock_irqsave(&sc->sc_pm_lock, flags);
1756		if (unlikely(ath9k_check_auto_sleep(sc) ||
1757			     (sc->ps_flags & (PS_WAIT_FOR_BEACON |
1758					      PS_WAIT_FOR_CAB |
1759					      PS_WAIT_FOR_PSPOLL_DATA))))
1760			ath_rx_ps(sc, skb);
1761		spin_unlock_irqrestore(&sc->sc_pm_lock, flags);
1762
1763		if (ah->caps.hw_caps & ATH9K_HW_CAP_ANT_DIV_COMB)
1764			ath_ant_comb_scan(sc, &rs);
1765
1766		ath_rx_send_to_mac80211(hw, sc, skb, rxs);
1767
1768requeue:
1769		if (edma) {
1770			list_add_tail(&bf->list, &sc->rx.rxbuf);
1771			ath_rx_edma_buf_link(sc, qtype);
1772		} else {
1773			list_move_tail(&bf->list, &sc->rx.rxbuf);
1774			ath_rx_buf_link(sc, bf);
1775		}
1776	} while (1);
1777
1778	spin_unlock_bh(&sc->rx.rxbuflock);
1779
1780	return 0;
1781}
1782