1 /*
2  * Copyright (c) 2008-2011 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 <linux/dma-mapping.h>
18 #include "ath9k.h"
19 
20 #define FUDGE 2
21 
22 static void ath9k_reset_beacon_status(struct ath_softc *sc)
23 {
24 	sc->beacon.tx_processed = false;
25 	sc->beacon.tx_last = false;
26 }
27 
28 /*
29  *  This function will modify certain transmit queue properties depending on
30  *  the operating mode of the station (AP or AdHoc).  Parameters are AIFS
31  *  settings and channel width min/max
32 */
33 static void ath9k_beaconq_config(struct ath_softc *sc)
34 {
35 	struct ath_hw *ah = sc->sc_ah;
36 	struct ath_common *common = ath9k_hw_common(ah);
37 	struct ath9k_tx_queue_info qi, qi_be;
38 	struct ath_txq *txq;
39 
40 	ath9k_hw_get_txq_props(ah, sc->beacon.beaconq, &qi);
41 
42 	if (sc->sc_ah->opmode == NL80211_IFTYPE_AP ||
43 	    sc->sc_ah->opmode == NL80211_IFTYPE_MESH_POINT) {
44 		/* Always burst out beacon and CAB traffic. */
45 		qi.tqi_aifs = 1;
46 		qi.tqi_cwmin = 0;
47 		qi.tqi_cwmax = 0;
48 	} else {
49 		/* Adhoc mode; important thing is to use 2x cwmin. */
50 		txq = sc->tx.txq_map[IEEE80211_AC_BE];
51 		ath9k_hw_get_txq_props(ah, txq->axq_qnum, &qi_be);
52 		qi.tqi_aifs = qi_be.tqi_aifs;
53 		if (ah->slottime == ATH9K_SLOT_TIME_20)
54 			qi.tqi_cwmin = 2*qi_be.tqi_cwmin;
55 		else
56 			qi.tqi_cwmin = 4*qi_be.tqi_cwmin;
57 		qi.tqi_cwmax = qi_be.tqi_cwmax;
58 	}
59 
60 	if (!ath9k_hw_set_txq_props(ah, sc->beacon.beaconq, &qi)) {
61 		ath_err(common, "Unable to update h/w beacon queue parameters\n");
62 	} else {
63 		ath9k_hw_resettxqueue(ah, sc->beacon.beaconq);
64 	}
65 }
66 
67 /*
68  *  Associates the beacon frame buffer with a transmit descriptor.  Will set
69  *  up rate codes, and channel flags. Beacons are always sent out at the
70  *  lowest rate, and are not retried.
71 */
72 static void ath9k_beacon_setup(struct ath_softc *sc, struct ieee80211_vif *vif,
73 			     struct ath_buf *bf, int rateidx)
74 {
75 	struct sk_buff *skb = bf->bf_mpdu;
76 	struct ath_hw *ah = sc->sc_ah;
77 	struct ath_common *common = ath9k_hw_common(ah);
78 	struct ath_tx_info info;
79 	struct ieee80211_supported_band *sband;
80 	u8 chainmask = ah->txchainmask;
81 	u8 rate = 0;
82 
83 	sband = &common->sbands[common->hw->conf.chandef.chan->band];
84 	rate = sband->bitrates[rateidx].hw_value;
85 	if (vif->bss_conf.use_short_preamble)
86 		rate |= sband->bitrates[rateidx].hw_value_short;
87 
88 	memset(&info, 0, sizeof(info));
89 	info.pkt_len = skb->len + FCS_LEN;
90 	info.type = ATH9K_PKT_TYPE_BEACON;
91 	info.txpower = MAX_RATE_POWER;
92 	info.keyix = ATH9K_TXKEYIX_INVALID;
93 	info.keytype = ATH9K_KEY_TYPE_CLEAR;
94 	info.flags = ATH9K_TXDESC_NOACK | ATH9K_TXDESC_CLRDMASK;
95 
96 	info.buf_addr[0] = bf->bf_buf_addr;
97 	info.buf_len[0] = roundup(skb->len, 4);
98 
99 	info.is_first = true;
100 	info.is_last = true;
101 
102 	info.qcu = sc->beacon.beaconq;
103 
104 	info.rates[0].Tries = 1;
105 	info.rates[0].Rate = rate;
106 	info.rates[0].ChSel = ath_txchainmask_reduction(sc, chainmask, rate);
107 
108 	ath9k_hw_set_txdesc(ah, bf->bf_desc, &info);
109 }
110 
111 static struct ath_buf *ath9k_beacon_generate(struct ieee80211_hw *hw,
112 					     struct ieee80211_vif *vif)
113 {
114 	struct ath_softc *sc = hw->priv;
115 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
116 	struct ath_buf *bf;
117 	struct ath_vif *avp = (void *)vif->drv_priv;
118 	struct sk_buff *skb;
119 	struct ath_txq *cabq = sc->beacon.cabq;
120 	struct ieee80211_tx_info *info;
121 	struct ieee80211_mgmt *mgmt_hdr;
122 	int cabq_depth;
123 
124 	if (avp->av_bcbuf == NULL)
125 		return NULL;
126 
127 	bf = avp->av_bcbuf;
128 	skb = bf->bf_mpdu;
129 	if (skb) {
130 		dma_unmap_single(sc->dev, bf->bf_buf_addr,
131 				 skb->len, DMA_TO_DEVICE);
132 		dev_kfree_skb_any(skb);
133 		bf->bf_buf_addr = 0;
134 		bf->bf_mpdu = NULL;
135 	}
136 
137 	skb = ieee80211_beacon_get(hw, vif);
138 	if (skb == NULL)
139 		return NULL;
140 
141 	bf->bf_mpdu = skb;
142 
143 	mgmt_hdr = (struct ieee80211_mgmt *)skb->data;
144 	mgmt_hdr->u.beacon.timestamp = avp->tsf_adjust;
145 
146 	info = IEEE80211_SKB_CB(skb);
147 	if (info->flags & IEEE80211_TX_CTL_ASSIGN_SEQ) {
148 		/*
149 		 * TODO: make sure the seq# gets assigned properly (vs. other
150 		 * TX frames)
151 		 */
152 		struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
153 		sc->tx.seq_no += 0x10;
154 		hdr->seq_ctrl &= cpu_to_le16(IEEE80211_SCTL_FRAG);
155 		hdr->seq_ctrl |= cpu_to_le16(sc->tx.seq_no);
156 	}
157 
158 	bf->bf_buf_addr = dma_map_single(sc->dev, skb->data,
159 					 skb->len, DMA_TO_DEVICE);
160 	if (unlikely(dma_mapping_error(sc->dev, bf->bf_buf_addr))) {
161 		dev_kfree_skb_any(skb);
162 		bf->bf_mpdu = NULL;
163 		bf->bf_buf_addr = 0;
164 		ath_err(common, "dma_mapping_error on beaconing\n");
165 		return NULL;
166 	}
167 
168 	skb = ieee80211_get_buffered_bc(hw, vif);
169 
170 	/*
171 	 * if the CABQ traffic from previous DTIM is pending and the current
172 	 *  beacon is also a DTIM.
173 	 *  1) if there is only one vif let the cab traffic continue.
174 	 *  2) if there are more than one vif and we are using staggered
175 	 *     beacons, then drain the cabq by dropping all the frames in
176 	 *     the cabq so that the current vifs cab traffic can be scheduled.
177 	 */
178 	spin_lock_bh(&cabq->axq_lock);
179 	cabq_depth = cabq->axq_depth;
180 	spin_unlock_bh(&cabq->axq_lock);
181 
182 	if (skb && cabq_depth) {
183 		if (sc->nvifs > 1) {
184 			ath_dbg(common, BEACON,
185 				"Flushing previous cabq traffic\n");
186 			ath_draintxq(sc, cabq);
187 		}
188 	}
189 
190 	ath9k_beacon_setup(sc, vif, bf, info->control.rates[0].idx);
191 
192 	if (skb)
193 		ath_tx_cabq(hw, vif, skb);
194 
195 	return bf;
196 }
197 
198 void ath9k_beacon_assign_slot(struct ath_softc *sc, struct ieee80211_vif *vif)
199 {
200 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
201 	struct ath_vif *avp = (void *)vif->drv_priv;
202 	int slot;
203 
204 	avp->av_bcbuf = list_first_entry(&sc->beacon.bbuf, struct ath_buf, list);
205 	list_del(&avp->av_bcbuf->list);
206 
207 	for (slot = 0; slot < ATH_BCBUF; slot++) {
208 		if (sc->beacon.bslot[slot] == NULL) {
209 			avp->av_bslot = slot;
210 			break;
211 		}
212 	}
213 
214 	sc->beacon.bslot[avp->av_bslot] = vif;
215 	sc->nbcnvifs++;
216 
217 	ath_dbg(common, CONFIG, "Added interface at beacon slot: %d\n",
218 		avp->av_bslot);
219 }
220 
221 void ath9k_beacon_remove_slot(struct ath_softc *sc, struct ieee80211_vif *vif)
222 {
223 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
224 	struct ath_vif *avp = (void *)vif->drv_priv;
225 	struct ath_buf *bf = avp->av_bcbuf;
226 
227 	ath_dbg(common, CONFIG, "Removing interface at beacon slot: %d\n",
228 		avp->av_bslot);
229 
230 	tasklet_disable(&sc->bcon_tasklet);
231 
232 	if (bf && bf->bf_mpdu) {
233 		struct sk_buff *skb = bf->bf_mpdu;
234 		dma_unmap_single(sc->dev, bf->bf_buf_addr,
235 				 skb->len, DMA_TO_DEVICE);
236 		dev_kfree_skb_any(skb);
237 		bf->bf_mpdu = NULL;
238 		bf->bf_buf_addr = 0;
239 	}
240 
241 	avp->av_bcbuf = NULL;
242 	sc->beacon.bslot[avp->av_bslot] = NULL;
243 	sc->nbcnvifs--;
244 	list_add_tail(&bf->list, &sc->beacon.bbuf);
245 
246 	tasklet_enable(&sc->bcon_tasklet);
247 }
248 
249 static int ath9k_beacon_choose_slot(struct ath_softc *sc)
250 {
251 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
252 	struct ath_beacon_config *cur_conf = &sc->cur_beacon_conf;
253 	u16 intval;
254 	u32 tsftu;
255 	u64 tsf;
256 	int slot;
257 
258 	if (sc->sc_ah->opmode != NL80211_IFTYPE_AP &&
259 	    sc->sc_ah->opmode != NL80211_IFTYPE_MESH_POINT) {
260 		ath_dbg(common, BEACON, "slot 0, tsf: %llu\n",
261 			ath9k_hw_gettsf64(sc->sc_ah));
262 		return 0;
263 	}
264 
265 	intval = cur_conf->beacon_interval ? : ATH_DEFAULT_BINTVAL;
266 	tsf = ath9k_hw_gettsf64(sc->sc_ah);
267 	tsf += TU_TO_USEC(sc->sc_ah->config.sw_beacon_response_time);
268 	tsftu = TSF_TO_TU((tsf * ATH_BCBUF) >>32, tsf * ATH_BCBUF);
269 	slot = (tsftu % (intval * ATH_BCBUF)) / intval;
270 
271 	ath_dbg(common, BEACON, "slot: %d tsf: %llu tsftu: %u\n",
272 		slot, tsf, tsftu / ATH_BCBUF);
273 
274 	return slot;
275 }
276 
277 static void ath9k_set_tsfadjust(struct ath_softc *sc, struct ieee80211_vif *vif)
278 {
279 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
280 	struct ath_beacon_config *cur_conf = &sc->cur_beacon_conf;
281 	struct ath_vif *avp = (void *)vif->drv_priv;
282 	u32 tsfadjust;
283 
284 	if (avp->av_bslot == 0)
285 		return;
286 
287 	tsfadjust = cur_conf->beacon_interval * avp->av_bslot;
288 	tsfadjust = TU_TO_USEC(tsfadjust) / ATH_BCBUF;
289 	avp->tsf_adjust = cpu_to_le64(tsfadjust);
290 
291 	ath_dbg(common, CONFIG, "tsfadjust is: %llu for bslot: %d\n",
292 		(unsigned long long)tsfadjust, avp->av_bslot);
293 }
294 
295 bool ath9k_csa_is_finished(struct ath_softc *sc, struct ieee80211_vif *vif)
296 {
297 	if (!vif || !vif->csa_active)
298 		return false;
299 
300 	if (!ieee80211_csa_is_complete(vif))
301 		return false;
302 
303 	ieee80211_csa_finish(vif);
304 	return true;
305 }
306 
307 static void ath9k_csa_update_vif(void *data, u8 *mac, struct ieee80211_vif *vif)
308 {
309 	struct ath_softc *sc = data;
310 	ath9k_csa_is_finished(sc, vif);
311 }
312 
313 void ath9k_csa_update(struct ath_softc *sc)
314 {
315 	ieee80211_iterate_active_interfaces_atomic(sc->hw,
316 						   IEEE80211_IFACE_ITER_NORMAL,
317 						   ath9k_csa_update_vif, sc);
318 }
319 
320 void ath9k_beacon_tasklet(unsigned long data)
321 {
322 	struct ath_softc *sc = (struct ath_softc *)data;
323 	struct ath_hw *ah = sc->sc_ah;
324 	struct ath_common *common = ath9k_hw_common(ah);
325 	struct ath_buf *bf = NULL;
326 	struct ieee80211_vif *vif;
327 	bool edma = !!(ah->caps.hw_caps & ATH9K_HW_CAP_EDMA);
328 	int slot;
329 
330 	if (test_bit(ATH_OP_HW_RESET, &common->op_flags)) {
331 		ath_dbg(common, RESET,
332 			"reset work is pending, skip beaconing now\n");
333 		return;
334 	}
335 
336 	/*
337 	 * Check if the previous beacon has gone out.  If
338 	 * not don't try to post another, skip this period
339 	 * and wait for the next.  Missed beacons indicate
340 	 * a problem and should not occur.  If we miss too
341 	 * many consecutive beacons reset the device.
342 	 */
343 	if (ath9k_hw_numtxpending(ah, sc->beacon.beaconq) != 0) {
344 		sc->beacon.bmisscnt++;
345 
346 		ath9k_hw_check_nav(ah);
347 
348 		/*
349 		 * If the previous beacon has not been transmitted
350 		 * and a MAC/BB hang has been identified, return
351 		 * here because a chip reset would have been
352 		 * initiated.
353 		 */
354 		if (!ath_hw_check(sc))
355 			return;
356 
357 		if (sc->beacon.bmisscnt < BSTUCK_THRESH * sc->nbcnvifs) {
358 			ath_dbg(common, BSTUCK,
359 				"missed %u consecutive beacons\n",
360 				sc->beacon.bmisscnt);
361 			ath9k_hw_stop_dma_queue(ah, sc->beacon.beaconq);
362 			if (sc->beacon.bmisscnt > 3)
363 				ath9k_hw_bstuck_nfcal(ah);
364 		} else if (sc->beacon.bmisscnt >= BSTUCK_THRESH) {
365 			ath_dbg(common, BSTUCK, "beacon is officially stuck\n");
366 			sc->beacon.bmisscnt = 0;
367 			ath9k_queue_reset(sc, RESET_TYPE_BEACON_STUCK);
368 		}
369 
370 		return;
371 	}
372 
373 	slot = ath9k_beacon_choose_slot(sc);
374 	vif = sc->beacon.bslot[slot];
375 
376 	/* EDMA devices check that in the tx completion function. */
377 	if (!edma && ath9k_csa_is_finished(sc, vif))
378 		return;
379 
380 	if (!vif || !vif->bss_conf.enable_beacon)
381 		return;
382 
383 	bf = ath9k_beacon_generate(sc->hw, vif);
384 
385 	if (sc->beacon.bmisscnt != 0) {
386 		ath_dbg(common, BSTUCK, "resume beacon xmit after %u misses\n",
387 			sc->beacon.bmisscnt);
388 		sc->beacon.bmisscnt = 0;
389 	}
390 
391 	/*
392 	 * Handle slot time change when a non-ERP station joins/leaves
393 	 * an 11g network.  The 802.11 layer notifies us via callback,
394 	 * we mark updateslot, then wait one beacon before effecting
395 	 * the change.  This gives associated stations at least one
396 	 * beacon interval to note the state change.
397 	 *
398 	 * NB: The slot time change state machine is clocked according
399 	 *     to whether we are bursting or staggering beacons.  We
400 	 *     recognize the request to update and record the current
401 	 *     slot then don't transition until that slot is reached
402 	 *     again.  If we miss a beacon for that slot then we'll be
403 	 *     slow to transition but we'll be sure at least one beacon
404 	 *     interval has passed.  When bursting slot is always left
405 	 *     set to ATH_BCBUF so this check is a noop.
406 	 */
407 	if (sc->beacon.updateslot == UPDATE) {
408 		sc->beacon.updateslot = COMMIT;
409 		sc->beacon.slotupdate = slot;
410 	} else if (sc->beacon.updateslot == COMMIT &&
411 		   sc->beacon.slotupdate == slot) {
412 		ah->slottime = sc->beacon.slottime;
413 		ath9k_hw_init_global_settings(ah);
414 		sc->beacon.updateslot = OK;
415 	}
416 
417 	if (bf) {
418 		ath9k_reset_beacon_status(sc);
419 
420 		ath_dbg(common, BEACON,
421 			"Transmitting beacon for slot: %d\n", slot);
422 
423 		/* NB: cabq traffic should already be queued and primed */
424 		ath9k_hw_puttxbuf(ah, sc->beacon.beaconq, bf->bf_daddr);
425 
426 		if (!edma)
427 			ath9k_hw_txstart(ah, sc->beacon.beaconq);
428 	}
429 }
430 
431 /*
432  * Both nexttbtt and intval have to be in usecs.
433  */
434 static void ath9k_beacon_init(struct ath_softc *sc, u32 nexttbtt,
435 			      u32 intval, bool reset_tsf)
436 {
437 	struct ath_hw *ah = sc->sc_ah;
438 
439 	ath9k_hw_disable_interrupts(ah);
440 	if (reset_tsf)
441 		ath9k_hw_reset_tsf(ah);
442 	ath9k_beaconq_config(sc);
443 	ath9k_hw_beaconinit(ah, nexttbtt, intval);
444 	sc->beacon.bmisscnt = 0;
445 	ath9k_hw_set_interrupts(ah);
446 	ath9k_hw_enable_interrupts(ah);
447 }
448 
449 /*
450  * For multi-bss ap support beacons are either staggered evenly over N slots or
451  * burst together.  For the former arrange for the SWBA to be delivered for each
452  * slot. Slots that are not occupied will generate nothing.
453  */
454 static void ath9k_beacon_config_ap(struct ath_softc *sc,
455 				   struct ath_beacon_config *conf)
456 {
457 	struct ath_hw *ah = sc->sc_ah;
458 
459 	ath9k_cmn_beacon_config_ap(ah, conf, ATH_BCBUF);
460 	ath9k_beacon_init(sc, conf->nexttbtt, conf->intval, false);
461 }
462 
463 static void ath9k_beacon_config_sta(struct ath_hw *ah,
464 				    struct ath_beacon_config *conf)
465 {
466 	struct ath9k_beacon_state bs;
467 
468 	if (ath9k_cmn_beacon_config_sta(ah, conf, &bs) == -EPERM)
469 		return;
470 
471 	ath9k_hw_disable_interrupts(ah);
472 	ath9k_hw_set_sta_beacon_timers(ah, &bs);
473 	ah->imask |= ATH9K_INT_BMISS;
474 
475 	ath9k_hw_set_interrupts(ah);
476 	ath9k_hw_enable_interrupts(ah);
477 }
478 
479 static void ath9k_beacon_config_adhoc(struct ath_softc *sc,
480 				      struct ath_beacon_config *conf)
481 {
482 	struct ath_hw *ah = sc->sc_ah;
483 	struct ath_common *common = ath9k_hw_common(ah);
484 
485 	ath9k_reset_beacon_status(sc);
486 
487 	ath9k_cmn_beacon_config_adhoc(ah, conf);
488 
489 	ath9k_beacon_init(sc, conf->nexttbtt, conf->intval, conf->ibss_creator);
490 
491 	/*
492 	 * Set the global 'beacon has been configured' flag for the
493 	 * joiner case in IBSS mode.
494 	 */
495 	if (!conf->ibss_creator && conf->enable_beacon)
496 		set_bit(ATH_OP_BEACONS, &common->op_flags);
497 }
498 
499 static bool ath9k_allow_beacon_config(struct ath_softc *sc,
500 				      struct ieee80211_vif *vif)
501 {
502 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
503 	struct ath_vif *avp = (void *)vif->drv_priv;
504 
505 	if (sc->sc_ah->opmode == NL80211_IFTYPE_AP) {
506 		if ((vif->type != NL80211_IFTYPE_AP) ||
507 		    (sc->nbcnvifs > 1)) {
508 			ath_dbg(common, CONFIG,
509 				"An AP interface is already present !\n");
510 			return false;
511 		}
512 	}
513 
514 	if (sc->sc_ah->opmode == NL80211_IFTYPE_STATION) {
515 		if ((vif->type == NL80211_IFTYPE_STATION) &&
516 		    test_bit(ATH_OP_BEACONS, &common->op_flags) &&
517 		    !avp->primary_sta_vif) {
518 			ath_dbg(common, CONFIG,
519 				"Beacon already configured for a station interface\n");
520 			return false;
521 		}
522 	}
523 
524 	return true;
525 }
526 
527 static void ath9k_cache_beacon_config(struct ath_softc *sc,
528 				      struct ieee80211_bss_conf *bss_conf)
529 {
530 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
531 	struct ath_beacon_config *cur_conf = &sc->cur_beacon_conf;
532 
533 	ath_dbg(common, BEACON,
534 		"Caching beacon data for BSS: %pM\n", bss_conf->bssid);
535 
536 	cur_conf->beacon_interval = bss_conf->beacon_int;
537 	cur_conf->dtim_period = bss_conf->dtim_period;
538 	cur_conf->dtim_count = 1;
539 	cur_conf->ibss_creator = bss_conf->ibss_creator;
540 
541 	/*
542 	 * It looks like mac80211 may end up using beacon interval of zero in
543 	 * some cases (at least for mesh point). Avoid getting into an
544 	 * infinite loop by using a bit safer value instead. To be safe,
545 	 * do sanity check on beacon interval for all operating modes.
546 	 */
547 	if (cur_conf->beacon_interval == 0)
548 		cur_conf->beacon_interval = 100;
549 
550 	cur_conf->bmiss_timeout =
551 		ATH_DEFAULT_BMISS_LIMIT * cur_conf->beacon_interval;
552 
553 	/*
554 	 * We don't parse dtim period from mac80211 during the driver
555 	 * initialization as it breaks association with hidden-ssid
556 	 * AP and it causes latency in roaming
557 	 */
558 	if (cur_conf->dtim_period == 0)
559 		cur_conf->dtim_period = 1;
560 
561 }
562 
563 void ath9k_beacon_config(struct ath_softc *sc, struct ieee80211_vif *vif,
564 			 u32 changed)
565 {
566 	struct ieee80211_bss_conf *bss_conf = &vif->bss_conf;
567 	struct ath_beacon_config *cur_conf = &sc->cur_beacon_conf;
568         struct ath_hw *ah = sc->sc_ah;
569         struct ath_common *common = ath9k_hw_common(ah);
570 	unsigned long flags;
571 	bool skip_beacon = false;
572 
573 	if (vif->type == NL80211_IFTYPE_AP)
574 		ath9k_set_tsfadjust(sc, vif);
575 
576 	if (!ath9k_allow_beacon_config(sc, vif))
577 		return;
578 
579 	if (sc->sc_ah->opmode == NL80211_IFTYPE_STATION) {
580 		ath9k_cache_beacon_config(sc, bss_conf);
581 		ath9k_set_beacon(sc);
582 		set_bit(ATH_OP_BEACONS, &common->op_flags);
583 		return;
584 	}
585 
586 	/*
587 	 * Take care of multiple interfaces when
588 	 * enabling/disabling SWBA.
589 	 */
590 	if (changed & BSS_CHANGED_BEACON_ENABLED) {
591 		if (!bss_conf->enable_beacon &&
592 		    (sc->nbcnvifs <= 1)) {
593 			cur_conf->enable_beacon = false;
594 		} else if (bss_conf->enable_beacon) {
595 			cur_conf->enable_beacon = true;
596 			ath9k_cache_beacon_config(sc, bss_conf);
597 		}
598 	}
599 
600 	/*
601 	 * Configure the HW beacon registers only when we have a valid
602 	 * beacon interval.
603 	 */
604 	if (cur_conf->beacon_interval) {
605 		/*
606 		 * If we are joining an existing IBSS network, start beaconing
607 		 * only after a TSF-sync has taken place. Ensure that this
608 		 * happens by setting the appropriate flags.
609 		 */
610 		if ((changed & BSS_CHANGED_IBSS) && !bss_conf->ibss_creator &&
611 		    bss_conf->enable_beacon) {
612 			spin_lock_irqsave(&sc->sc_pm_lock, flags);
613 			sc->ps_flags |= PS_BEACON_SYNC | PS_WAIT_FOR_BEACON;
614 			spin_unlock_irqrestore(&sc->sc_pm_lock, flags);
615 			skip_beacon = true;
616 		} else {
617 			ath9k_set_beacon(sc);
618 		}
619 
620 		/*
621 		 * Do not set the ATH_OP_BEACONS flag for IBSS joiner mode
622 		 * here, it is done in ath9k_beacon_config_adhoc().
623 		 */
624 		if (cur_conf->enable_beacon && !skip_beacon)
625 			set_bit(ATH_OP_BEACONS, &common->op_flags);
626 		else
627 			clear_bit(ATH_OP_BEACONS, &common->op_flags);
628 	}
629 }
630 
631 void ath9k_set_beacon(struct ath_softc *sc)
632 {
633 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
634 	struct ath_beacon_config *cur_conf = &sc->cur_beacon_conf;
635 
636 	switch (sc->sc_ah->opmode) {
637 	case NL80211_IFTYPE_AP:
638 	case NL80211_IFTYPE_MESH_POINT:
639 		ath9k_beacon_config_ap(sc, cur_conf);
640 		break;
641 	case NL80211_IFTYPE_ADHOC:
642 		ath9k_beacon_config_adhoc(sc, cur_conf);
643 		break;
644 	case NL80211_IFTYPE_STATION:
645 		ath9k_beacon_config_sta(sc->sc_ah, cur_conf);
646 		break;
647 	default:
648 		ath_dbg(common, CONFIG, "Unsupported beaconing mode\n");
649 		return;
650 	}
651 }
652