1 /*
2  * Copyright (c) 2014 Qualcomm Atheros, 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 
19 /* Set/change channels.  If the channel is really being changed, it's done
20  * by reseting the chip.  To accomplish this we must first cleanup any pending
21  * DMA, then restart stuff.
22  */
23 static int ath_set_channel(struct ath_softc *sc)
24 {
25 	struct ath_hw *ah = sc->sc_ah;
26 	struct ath_common *common = ath9k_hw_common(ah);
27 	struct ieee80211_hw *hw = sc->hw;
28 	struct ath9k_channel *hchan;
29 	struct cfg80211_chan_def *chandef = &sc->cur_chan->chandef;
30 	struct ieee80211_channel *chan = chandef->chan;
31 	int pos = chan->hw_value;
32 	int old_pos = -1;
33 	int r;
34 
35 	if (test_bit(ATH_OP_INVALID, &common->op_flags))
36 		return -EIO;
37 
38 	if (ah->curchan)
39 		old_pos = ah->curchan - &ah->channels[0];
40 
41 	ath_dbg(common, CONFIG, "Set channel: %d MHz width: %d\n",
42 		chan->center_freq, chandef->width);
43 
44 	/* update survey stats for the old channel before switching */
45 	spin_lock_bh(&common->cc_lock);
46 	ath_update_survey_stats(sc);
47 	spin_unlock_bh(&common->cc_lock);
48 
49 	ath9k_cmn_get_channel(hw, ah, chandef);
50 
51 	/* If the operating channel changes, change the survey in-use flags
52 	 * along with it.
53 	 * Reset the survey data for the new channel, unless we're switching
54 	 * back to the operating channel from an off-channel operation.
55 	 */
56 	if (!sc->cur_chan->offchannel && sc->cur_survey != &sc->survey[pos]) {
57 		if (sc->cur_survey)
58 			sc->cur_survey->filled &= ~SURVEY_INFO_IN_USE;
59 
60 		sc->cur_survey = &sc->survey[pos];
61 
62 		memset(sc->cur_survey, 0, sizeof(struct survey_info));
63 		sc->cur_survey->filled |= SURVEY_INFO_IN_USE;
64 	} else if (!(sc->survey[pos].filled & SURVEY_INFO_IN_USE)) {
65 		memset(&sc->survey[pos], 0, sizeof(struct survey_info));
66 	}
67 
68 	hchan = &sc->sc_ah->channels[pos];
69 	r = ath_reset(sc, hchan);
70 	if (r)
71 		return r;
72 
73 	/* The most recent snapshot of channel->noisefloor for the old
74 	 * channel is only available after the hardware reset. Copy it to
75 	 * the survey stats now.
76 	 */
77 	if (old_pos >= 0)
78 		ath_update_survey_nf(sc, old_pos);
79 
80 	/* Enable radar pulse detection if on a DFS channel. Spectral
81 	 * scanning and radar detection can not be used concurrently.
82 	 */
83 	if (hw->conf.radar_enabled) {
84 		u32 rxfilter;
85 
86 		rxfilter = ath9k_hw_getrxfilter(ah);
87 		rxfilter |= ATH9K_RX_FILTER_PHYRADAR |
88 				ATH9K_RX_FILTER_PHYERR;
89 		ath9k_hw_setrxfilter(ah, rxfilter);
90 		ath_dbg(common, DFS, "DFS enabled at freq %d\n",
91 			chan->center_freq);
92 	} else {
93 		/* perform spectral scan if requested. */
94 		if (test_bit(ATH_OP_SCANNING, &common->op_flags) &&
95 			sc->spec_priv.spectral_mode == SPECTRAL_CHANSCAN)
96 			ath9k_cmn_spectral_scan_trigger(common, &sc->spec_priv);
97 	}
98 
99 	return 0;
100 }
101 
102 void ath_chanctx_init(struct ath_softc *sc)
103 {
104 	struct ath_chanctx *ctx;
105 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
106 	struct ieee80211_supported_band *sband;
107 	struct ieee80211_channel *chan;
108 	int i, j;
109 
110 	sband = &common->sbands[NL80211_BAND_2GHZ];
111 	if (!sband->n_channels)
112 		sband = &common->sbands[NL80211_BAND_5GHZ];
113 
114 	chan = &sband->channels[0];
115 	for (i = 0; i < ATH9K_NUM_CHANCTX; i++) {
116 		ctx = &sc->chanctx[i];
117 		cfg80211_chandef_create(&ctx->chandef, chan, NL80211_CHAN_HT20);
118 		INIT_LIST_HEAD(&ctx->vifs);
119 		ctx->txpower = ATH_TXPOWER_MAX;
120 		ctx->flush_timeout = HZ / 5; /* 200ms */
121 		for (j = 0; j < ARRAY_SIZE(ctx->acq); j++)
122 			INIT_LIST_HEAD(&ctx->acq[j]);
123 	}
124 }
125 
126 void ath_chanctx_set_channel(struct ath_softc *sc, struct ath_chanctx *ctx,
127 			     struct cfg80211_chan_def *chandef)
128 {
129 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
130 	bool cur_chan;
131 
132 	spin_lock_bh(&sc->chan_lock);
133 	if (chandef)
134 		memcpy(&ctx->chandef, chandef, sizeof(*chandef));
135 	cur_chan = sc->cur_chan == ctx;
136 	spin_unlock_bh(&sc->chan_lock);
137 
138 	if (!cur_chan) {
139 		ath_dbg(common, CHAN_CTX,
140 			"Current context differs from the new context\n");
141 		return;
142 	}
143 
144 	ath_set_channel(sc);
145 }
146 
147 #ifdef CONFIG_ATH9K_CHANNEL_CONTEXT
148 
149 /*************/
150 /* Utilities */
151 /*************/
152 
153 struct ath_chanctx* ath_is_go_chanctx_present(struct ath_softc *sc)
154 {
155 	struct ath_chanctx *ctx;
156 	struct ath_vif *avp;
157 	struct ieee80211_vif *vif;
158 
159 	spin_lock_bh(&sc->chan_lock);
160 
161 	ath_for_each_chanctx(sc, ctx) {
162 		if (!ctx->active)
163 			continue;
164 
165 		list_for_each_entry(avp, &ctx->vifs, list) {
166 			vif = avp->vif;
167 
168 			if (ieee80211_vif_type_p2p(vif) == NL80211_IFTYPE_P2P_GO) {
169 				spin_unlock_bh(&sc->chan_lock);
170 				return ctx;
171 			}
172 		}
173 	}
174 
175 	spin_unlock_bh(&sc->chan_lock);
176 	return NULL;
177 }
178 
179 /**********************************************************/
180 /* Functions to handle the channel context state machine. */
181 /**********************************************************/
182 
183 static const char *offchannel_state_string(enum ath_offchannel_state state)
184 {
185 	switch (state) {
186 		case_rtn_string(ATH_OFFCHANNEL_IDLE);
187 		case_rtn_string(ATH_OFFCHANNEL_PROBE_SEND);
188 		case_rtn_string(ATH_OFFCHANNEL_PROBE_WAIT);
189 		case_rtn_string(ATH_OFFCHANNEL_SUSPEND);
190 		case_rtn_string(ATH_OFFCHANNEL_ROC_START);
191 		case_rtn_string(ATH_OFFCHANNEL_ROC_WAIT);
192 		case_rtn_string(ATH_OFFCHANNEL_ROC_DONE);
193 	default:
194 		return "unknown";
195 	}
196 }
197 
198 static const char *chanctx_event_string(enum ath_chanctx_event ev)
199 {
200 	switch (ev) {
201 		case_rtn_string(ATH_CHANCTX_EVENT_BEACON_PREPARE);
202 		case_rtn_string(ATH_CHANCTX_EVENT_BEACON_SENT);
203 		case_rtn_string(ATH_CHANCTX_EVENT_TSF_TIMER);
204 		case_rtn_string(ATH_CHANCTX_EVENT_BEACON_RECEIVED);
205 		case_rtn_string(ATH_CHANCTX_EVENT_AUTHORIZED);
206 		case_rtn_string(ATH_CHANCTX_EVENT_SWITCH);
207 		case_rtn_string(ATH_CHANCTX_EVENT_ASSIGN);
208 		case_rtn_string(ATH_CHANCTX_EVENT_UNASSIGN);
209 		case_rtn_string(ATH_CHANCTX_EVENT_CHANGE);
210 		case_rtn_string(ATH_CHANCTX_EVENT_ENABLE_MULTICHANNEL);
211 	default:
212 		return "unknown";
213 	}
214 }
215 
216 static const char *chanctx_state_string(enum ath_chanctx_state state)
217 {
218 	switch (state) {
219 		case_rtn_string(ATH_CHANCTX_STATE_IDLE);
220 		case_rtn_string(ATH_CHANCTX_STATE_WAIT_FOR_BEACON);
221 		case_rtn_string(ATH_CHANCTX_STATE_WAIT_FOR_TIMER);
222 		case_rtn_string(ATH_CHANCTX_STATE_SWITCH);
223 		case_rtn_string(ATH_CHANCTX_STATE_FORCE_ACTIVE);
224 	default:
225 		return "unknown";
226 	}
227 }
228 
229 static u32 chanctx_event_delta(struct ath_softc *sc)
230 {
231 	u64 ms;
232 	struct timespec ts, *old;
233 
234 	getrawmonotonic(&ts);
235 	old = &sc->last_event_time;
236 	ms = ts.tv_sec * 1000 + ts.tv_nsec / 1000000;
237 	ms -= old->tv_sec * 1000 + old->tv_nsec / 1000000;
238 	sc->last_event_time = ts;
239 
240 	return (u32)ms;
241 }
242 
243 void ath_chanctx_check_active(struct ath_softc *sc, struct ath_chanctx *ctx)
244 {
245 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
246 	struct ath_chanctx *ictx;
247 	struct ath_vif *avp;
248 	bool active = false;
249 	u8 n_active = 0;
250 
251 	if (!ctx)
252 		return;
253 
254 	if (ctx == &sc->offchannel.chan) {
255 		spin_lock_bh(&sc->chan_lock);
256 
257 		if (likely(sc->sched.channel_switch_time))
258 			ctx->flush_timeout =
259 				usecs_to_jiffies(sc->sched.channel_switch_time);
260 		else
261 			ctx->flush_timeout =
262 				msecs_to_jiffies(10);
263 
264 		spin_unlock_bh(&sc->chan_lock);
265 
266 		/*
267 		 * There is no need to iterate over the
268 		 * active/assigned channel contexts if
269 		 * the current context is offchannel.
270 		 */
271 		return;
272 	}
273 
274 	ictx = ctx;
275 
276 	list_for_each_entry(avp, &ctx->vifs, list) {
277 		struct ieee80211_vif *vif = avp->vif;
278 
279 		switch (vif->type) {
280 		case NL80211_IFTYPE_P2P_CLIENT:
281 		case NL80211_IFTYPE_STATION:
282 			if (avp->assoc)
283 				active = true;
284 			break;
285 		default:
286 			active = true;
287 			break;
288 		}
289 	}
290 	ctx->active = active;
291 
292 	ath_for_each_chanctx(sc, ctx) {
293 		if (!ctx->assigned || list_empty(&ctx->vifs))
294 			continue;
295 		n_active++;
296 	}
297 
298 	spin_lock_bh(&sc->chan_lock);
299 
300 	if (n_active <= 1) {
301 		ictx->flush_timeout = HZ / 5;
302 		clear_bit(ATH_OP_MULTI_CHANNEL, &common->op_flags);
303 		spin_unlock_bh(&sc->chan_lock);
304 		return;
305 	}
306 
307 	ictx->flush_timeout = usecs_to_jiffies(sc->sched.channel_switch_time);
308 
309 	if (test_and_set_bit(ATH_OP_MULTI_CHANNEL, &common->op_flags)) {
310 		spin_unlock_bh(&sc->chan_lock);
311 		return;
312 	}
313 
314 	spin_unlock_bh(&sc->chan_lock);
315 
316 	if (ath9k_is_chanctx_enabled()) {
317 		ath_chanctx_event(sc, NULL,
318 				  ATH_CHANCTX_EVENT_ENABLE_MULTICHANNEL);
319 	}
320 }
321 
322 static struct ath_chanctx *
323 ath_chanctx_get_next(struct ath_softc *sc, struct ath_chanctx *ctx)
324 {
325 	int idx = ctx - &sc->chanctx[0];
326 
327 	return &sc->chanctx[!idx];
328 }
329 
330 static void ath_chanctx_adjust_tbtt_delta(struct ath_softc *sc)
331 {
332 	struct ath_chanctx *prev, *cur;
333 	struct timespec ts;
334 	u32 cur_tsf, prev_tsf, beacon_int;
335 	s32 offset;
336 
337 	beacon_int = TU_TO_USEC(sc->cur_chan->beacon.beacon_interval);
338 
339 	cur = sc->cur_chan;
340 	prev = ath_chanctx_get_next(sc, cur);
341 
342 	if (!prev->switch_after_beacon)
343 		return;
344 
345 	getrawmonotonic(&ts);
346 	cur_tsf = (u32) cur->tsf_val +
347 		  ath9k_hw_get_tsf_offset(&cur->tsf_ts, &ts);
348 
349 	prev_tsf = prev->last_beacon - (u32) prev->tsf_val + cur_tsf;
350 	prev_tsf -= ath9k_hw_get_tsf_offset(&prev->tsf_ts, &ts);
351 
352 	/* Adjust the TSF time of the AP chanctx to keep its beacons
353 	 * at half beacon interval offset relative to the STA chanctx.
354 	 */
355 	offset = cur_tsf - prev_tsf;
356 
357 	/* Ignore stale data or spurious timestamps */
358 	if (offset < 0 || offset > 3 * beacon_int)
359 		return;
360 
361 	offset = beacon_int / 2 - (offset % beacon_int);
362 	prev->tsf_val += offset;
363 }
364 
365 /* Configure the TSF based hardware timer for a channel switch.
366  * Also set up backup software timer, in case the gen timer fails.
367  * This could be caused by a hardware reset.
368  */
369 static void ath_chanctx_setup_timer(struct ath_softc *sc, u32 tsf_time)
370 {
371 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
372 	struct ath_hw *ah = sc->sc_ah;
373 	unsigned long timeout;
374 
375 	ath9k_hw_gen_timer_start(ah, sc->p2p_ps_timer, tsf_time, 1000000);
376 	tsf_time -= ath9k_hw_gettsf32(ah);
377 	timeout = msecs_to_jiffies(tsf_time / 1000) + 1;
378 	mod_timer(&sc->sched.timer, jiffies + timeout);
379 
380 	ath_dbg(common, CHAN_CTX,
381 		"Setup chanctx timer with timeout: %d (%d) ms\n",
382 		tsf_time / 1000, jiffies_to_msecs(timeout));
383 }
384 
385 static void ath_chanctx_handle_bmiss(struct ath_softc *sc,
386 				     struct ath_chanctx *ctx,
387 				     struct ath_vif *avp)
388 {
389 	/*
390 	 * Clear the extend_absence flag if it had been
391 	 * set during the previous beacon transmission,
392 	 * since we need to revert to the normal NoA
393 	 * schedule.
394 	 */
395 	if (ctx->active && sc->sched.extend_absence) {
396 		avp->noa_duration = 0;
397 		sc->sched.extend_absence = false;
398 	}
399 
400 	/* If at least two consecutive beacons were missed on the STA
401 	 * chanctx, stay on the STA channel for one extra beacon period,
402 	 * to resync the timer properly.
403 	 */
404 	if (ctx->active && sc->sched.beacon_miss >= 2) {
405 		avp->noa_duration = 0;
406 		sc->sched.extend_absence = true;
407 	}
408 }
409 
410 static void ath_chanctx_offchannel_noa(struct ath_softc *sc,
411 				       struct ath_chanctx *ctx,
412 				       struct ath_vif *avp,
413 				       u32 tsf_time)
414 {
415 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
416 
417 	avp->noa_index++;
418 	avp->offchannel_start = tsf_time;
419 	avp->offchannel_duration = sc->sched.offchannel_duration;
420 
421 	ath_dbg(common, CHAN_CTX,
422 		"offchannel noa_duration: %d, noa_start: %u, noa_index: %d\n",
423 		avp->offchannel_duration,
424 		avp->offchannel_start,
425 		avp->noa_index);
426 
427 	/*
428 	 * When multiple contexts are active, the NoA
429 	 * has to be recalculated and advertised after
430 	 * an offchannel operation.
431 	 */
432 	if (ctx->active && avp->noa_duration)
433 		avp->noa_duration = 0;
434 }
435 
436 static void ath_chanctx_set_periodic_noa(struct ath_softc *sc,
437 					 struct ath_vif *avp,
438 					 struct ath_beacon_config *cur_conf,
439 					 u32 tsf_time,
440 					 u32 beacon_int)
441 {
442 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
443 
444 	avp->noa_index++;
445 	avp->noa_start = tsf_time;
446 
447 	if (sc->sched.extend_absence)
448 		avp->noa_duration = (3 * beacon_int / 2) +
449 			sc->sched.channel_switch_time;
450 	else
451 		avp->noa_duration =
452 			TU_TO_USEC(cur_conf->beacon_interval) / 2 +
453 			sc->sched.channel_switch_time;
454 
455 	if (test_bit(ATH_OP_SCANNING, &common->op_flags) ||
456 	    sc->sched.extend_absence)
457 		avp->periodic_noa = false;
458 	else
459 		avp->periodic_noa = true;
460 
461 	ath_dbg(common, CHAN_CTX,
462 		"noa_duration: %d, noa_start: %u, noa_index: %d, periodic: %d\n",
463 		avp->noa_duration,
464 		avp->noa_start,
465 		avp->noa_index,
466 		avp->periodic_noa);
467 }
468 
469 static void ath_chanctx_set_oneshot_noa(struct ath_softc *sc,
470 					struct ath_vif *avp,
471 					u32 tsf_time,
472 					u32 duration)
473 {
474 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
475 
476 	avp->noa_index++;
477 	avp->noa_start = tsf_time;
478 	avp->periodic_noa = false;
479 	avp->oneshot_noa = true;
480 	avp->noa_duration = duration + sc->sched.channel_switch_time;
481 
482 	ath_dbg(common, CHAN_CTX,
483 		"oneshot noa_duration: %d, noa_start: %u, noa_index: %d, periodic: %d\n",
484 		avp->noa_duration,
485 		avp->noa_start,
486 		avp->noa_index,
487 		avp->periodic_noa);
488 }
489 
490 void ath_chanctx_event(struct ath_softc *sc, struct ieee80211_vif *vif,
491 		       enum ath_chanctx_event ev)
492 {
493 	struct ath_hw *ah = sc->sc_ah;
494 	struct ath_common *common = ath9k_hw_common(ah);
495 	struct ath_beacon_config *cur_conf;
496 	struct ath_vif *avp = NULL;
497 	struct ath_chanctx *ctx;
498 	u32 tsf_time;
499 	u32 beacon_int;
500 
501 	if (vif)
502 		avp = (struct ath_vif *) vif->drv_priv;
503 
504 	spin_lock_bh(&sc->chan_lock);
505 
506 	ath_dbg(common, CHAN_CTX, "cur_chan: %d MHz, event: %s, state: %s, delta: %u ms\n",
507 		sc->cur_chan->chandef.center_freq1,
508 		chanctx_event_string(ev),
509 		chanctx_state_string(sc->sched.state),
510 		chanctx_event_delta(sc));
511 
512 	switch (ev) {
513 	case ATH_CHANCTX_EVENT_BEACON_PREPARE:
514 		if (avp->offchannel_duration)
515 			avp->offchannel_duration = 0;
516 
517 		if (avp->oneshot_noa) {
518 			avp->noa_duration = 0;
519 			avp->oneshot_noa = false;
520 
521 			ath_dbg(common, CHAN_CTX,
522 				"Clearing oneshot NoA\n");
523 		}
524 
525 		if (avp->chanctx != sc->cur_chan) {
526 			ath_dbg(common, CHAN_CTX,
527 				"Contexts differ, not preparing beacon\n");
528 			break;
529 		}
530 
531 		if (sc->sched.offchannel_pending && !sc->sched.wait_switch) {
532 			sc->sched.offchannel_pending = false;
533 			sc->next_chan = &sc->offchannel.chan;
534 			sc->sched.state = ATH_CHANCTX_STATE_WAIT_FOR_BEACON;
535 			ath_dbg(common, CHAN_CTX,
536 				"Setting offchannel_pending to false\n");
537 		}
538 
539 		ctx = ath_chanctx_get_next(sc, sc->cur_chan);
540 		if (ctx->active && sc->sched.state == ATH_CHANCTX_STATE_IDLE) {
541 			sc->next_chan = ctx;
542 			sc->sched.state = ATH_CHANCTX_STATE_WAIT_FOR_BEACON;
543 			ath_dbg(common, CHAN_CTX,
544 				"Set next context, move chanctx state to WAIT_FOR_BEACON\n");
545 		}
546 
547 		/* if the timer missed its window, use the next interval */
548 		if (sc->sched.state == ATH_CHANCTX_STATE_WAIT_FOR_TIMER) {
549 			sc->sched.state = ATH_CHANCTX_STATE_WAIT_FOR_BEACON;
550 			ath_dbg(common, CHAN_CTX,
551 				"Move chanctx state from WAIT_FOR_TIMER to WAIT_FOR_BEACON\n");
552 		}
553 
554 		if (sc->sched.mgd_prepare_tx)
555 			sc->sched.state = ATH_CHANCTX_STATE_WAIT_FOR_BEACON;
556 
557 		/*
558 		 * When a context becomes inactive, for example,
559 		 * disassociation of a station context, the NoA
560 		 * attribute needs to be removed from subsequent
561 		 * beacons.
562 		 */
563 		if (!ctx->active && avp->noa_duration &&
564 		    sc->sched.state != ATH_CHANCTX_STATE_WAIT_FOR_BEACON) {
565 			avp->noa_duration = 0;
566 			avp->periodic_noa = false;
567 
568 			ath_dbg(common, CHAN_CTX,
569 				"Clearing NoA schedule\n");
570 		}
571 
572 		if (sc->sched.state != ATH_CHANCTX_STATE_WAIT_FOR_BEACON)
573 			break;
574 
575 		ath_dbg(common, CHAN_CTX, "Preparing beacon for vif: %pM\n", vif->addr);
576 
577 		sc->sched.beacon_pending = true;
578 		sc->sched.next_tbtt = REG_READ(ah, AR_NEXT_TBTT_TIMER);
579 
580 		cur_conf = &sc->cur_chan->beacon;
581 		beacon_int = TU_TO_USEC(cur_conf->beacon_interval);
582 
583 		/* defer channel switch by a quarter beacon interval */
584 		tsf_time = sc->sched.next_tbtt + beacon_int / 4;
585 		sc->sched.switch_start_time = tsf_time;
586 		sc->cur_chan->last_beacon = sc->sched.next_tbtt;
587 
588 		/*
589 		 * If an offchannel switch is scheduled to happen after
590 		 * a beacon transmission, update the NoA with one-shot
591 		 * values and increment the index.
592 		 */
593 		if (sc->next_chan == &sc->offchannel.chan) {
594 			ath_chanctx_offchannel_noa(sc, ctx, avp, tsf_time);
595 			break;
596 		}
597 
598 		ath_chanctx_handle_bmiss(sc, ctx, avp);
599 
600 		/*
601 		 * If a mgd_prepare_tx() has been called by mac80211,
602 		 * a one-shot NoA needs to be sent. This can happen
603 		 * with one or more active channel contexts - in both
604 		 * cases, a new NoA schedule has to be advertised.
605 		 */
606 		if (sc->sched.mgd_prepare_tx) {
607 			ath_chanctx_set_oneshot_noa(sc, avp, tsf_time,
608 						    jiffies_to_usecs(HZ / 5));
609 			break;
610 		}
611 
612 		/* Prevent wrap-around issues */
613 		if (avp->noa_duration && tsf_time - avp->noa_start > BIT(30))
614 			avp->noa_duration = 0;
615 
616 		/*
617 		 * If multiple contexts are active, start periodic
618 		 * NoA and increment the index for the first
619 		 * announcement.
620 		 */
621 		if (ctx->active &&
622 		    (!avp->noa_duration || sc->sched.force_noa_update))
623 			ath_chanctx_set_periodic_noa(sc, avp, cur_conf,
624 						     tsf_time, beacon_int);
625 
626 		if (ctx->active && sc->sched.force_noa_update)
627 			sc->sched.force_noa_update = false;
628 
629 		break;
630 	case ATH_CHANCTX_EVENT_BEACON_SENT:
631 		if (!sc->sched.beacon_pending) {
632 			ath_dbg(common, CHAN_CTX,
633 				"No pending beacon\n");
634 			break;
635 		}
636 
637 		sc->sched.beacon_pending = false;
638 
639 		if (sc->sched.mgd_prepare_tx) {
640 			sc->sched.mgd_prepare_tx = false;
641 			complete(&sc->go_beacon);
642 			ath_dbg(common, CHAN_CTX,
643 				"Beacon sent, complete go_beacon\n");
644 			break;
645 		}
646 
647 		if (sc->sched.state != ATH_CHANCTX_STATE_WAIT_FOR_BEACON)
648 			break;
649 
650 		ath_dbg(common, CHAN_CTX,
651 			"Move chanctx state to WAIT_FOR_TIMER\n");
652 
653 		sc->sched.state = ATH_CHANCTX_STATE_WAIT_FOR_TIMER;
654 		ath_chanctx_setup_timer(sc, sc->sched.switch_start_time);
655 		break;
656 	case ATH_CHANCTX_EVENT_TSF_TIMER:
657 		if (sc->sched.state != ATH_CHANCTX_STATE_WAIT_FOR_TIMER)
658 			break;
659 
660 		if (!sc->cur_chan->switch_after_beacon &&
661 		    sc->sched.beacon_pending)
662 			sc->sched.beacon_miss++;
663 
664 		ath_dbg(common, CHAN_CTX,
665 			"Move chanctx state to SWITCH\n");
666 
667 		sc->sched.state = ATH_CHANCTX_STATE_SWITCH;
668 		ieee80211_queue_work(sc->hw, &sc->chanctx_work);
669 		break;
670 	case ATH_CHANCTX_EVENT_BEACON_RECEIVED:
671 		if (!test_bit(ATH_OP_MULTI_CHANNEL, &common->op_flags) ||
672 		    sc->cur_chan == &sc->offchannel.chan)
673 			break;
674 
675 		sc->sched.beacon_pending = false;
676 		sc->sched.beacon_miss = 0;
677 
678 		if (sc->sched.state == ATH_CHANCTX_STATE_FORCE_ACTIVE ||
679 		    !sc->sched.beacon_adjust ||
680 		    !sc->cur_chan->tsf_val)
681 			break;
682 
683 		ath_chanctx_adjust_tbtt_delta(sc);
684 
685 		/* TSF time might have been updated by the incoming beacon,
686 		 * need update the channel switch timer to reflect the change.
687 		 */
688 		tsf_time = sc->sched.switch_start_time;
689 		tsf_time -= (u32) sc->cur_chan->tsf_val +
690 			ath9k_hw_get_tsf_offset(&sc->cur_chan->tsf_ts, NULL);
691 		tsf_time += ath9k_hw_gettsf32(ah);
692 
693 		sc->sched.beacon_adjust = false;
694 		ath_chanctx_setup_timer(sc, tsf_time);
695 		break;
696 	case ATH_CHANCTX_EVENT_AUTHORIZED:
697 		if (sc->sched.state != ATH_CHANCTX_STATE_FORCE_ACTIVE ||
698 		    avp->chanctx != sc->cur_chan)
699 			break;
700 
701 		ath_dbg(common, CHAN_CTX,
702 			"Move chanctx state from FORCE_ACTIVE to IDLE\n");
703 
704 		sc->sched.state = ATH_CHANCTX_STATE_IDLE;
705 		/* fall through */
706 	case ATH_CHANCTX_EVENT_SWITCH:
707 		if (!test_bit(ATH_OP_MULTI_CHANNEL, &common->op_flags) ||
708 		    sc->sched.state == ATH_CHANCTX_STATE_FORCE_ACTIVE ||
709 		    sc->cur_chan->switch_after_beacon ||
710 		    sc->cur_chan == &sc->offchannel.chan)
711 			break;
712 
713 		/* If this is a station chanctx, stay active for a half
714 		 * beacon period (minus channel switch time)
715 		 */
716 		sc->next_chan = ath_chanctx_get_next(sc, sc->cur_chan);
717 		cur_conf = &sc->cur_chan->beacon;
718 
719 		ath_dbg(common, CHAN_CTX,
720 			"Move chanctx state to WAIT_FOR_TIMER (event SWITCH)\n");
721 
722 		sc->sched.state = ATH_CHANCTX_STATE_WAIT_FOR_TIMER;
723 		sc->sched.wait_switch = false;
724 
725 		tsf_time = TU_TO_USEC(cur_conf->beacon_interval) / 2;
726 
727 		if (sc->sched.extend_absence) {
728 			sc->sched.beacon_miss = 0;
729 			tsf_time *= 3;
730 		}
731 
732 		tsf_time -= sc->sched.channel_switch_time;
733 		tsf_time += ath9k_hw_gettsf32(sc->sc_ah);
734 		sc->sched.switch_start_time = tsf_time;
735 
736 		ath_chanctx_setup_timer(sc, tsf_time);
737 		sc->sched.beacon_pending = true;
738 		sc->sched.beacon_adjust = true;
739 		break;
740 	case ATH_CHANCTX_EVENT_ENABLE_MULTICHANNEL:
741 		if (sc->cur_chan == &sc->offchannel.chan ||
742 		    sc->cur_chan->switch_after_beacon)
743 			break;
744 
745 		sc->next_chan = ath_chanctx_get_next(sc, sc->cur_chan);
746 		ieee80211_queue_work(sc->hw, &sc->chanctx_work);
747 		break;
748 	case ATH_CHANCTX_EVENT_UNASSIGN:
749 		if (sc->cur_chan->assigned) {
750 			if (sc->next_chan && !sc->next_chan->assigned &&
751 			    sc->next_chan != &sc->offchannel.chan)
752 				sc->sched.state = ATH_CHANCTX_STATE_IDLE;
753 			break;
754 		}
755 
756 		ctx = ath_chanctx_get_next(sc, sc->cur_chan);
757 		sc->sched.state = ATH_CHANCTX_STATE_IDLE;
758 		if (!ctx->assigned)
759 			break;
760 
761 		sc->next_chan = ctx;
762 		ieee80211_queue_work(sc->hw, &sc->chanctx_work);
763 		break;
764 	case ATH_CHANCTX_EVENT_ASSIGN:
765 		break;
766 	case ATH_CHANCTX_EVENT_CHANGE:
767 		break;
768 	}
769 
770 	spin_unlock_bh(&sc->chan_lock);
771 }
772 
773 void ath_chanctx_beacon_sent_ev(struct ath_softc *sc,
774 				enum ath_chanctx_event ev)
775 {
776 	if (sc->sched.beacon_pending)
777 		ath_chanctx_event(sc, NULL, ev);
778 }
779 
780 void ath_chanctx_beacon_recv_ev(struct ath_softc *sc,
781 				enum ath_chanctx_event ev)
782 {
783 	ath_chanctx_event(sc, NULL, ev);
784 }
785 
786 static int ath_scan_channel_duration(struct ath_softc *sc,
787 				     struct ieee80211_channel *chan)
788 {
789 	struct cfg80211_scan_request *req = sc->offchannel.scan_req;
790 
791 	if (!req->n_ssids || (chan->flags & IEEE80211_CHAN_NO_IR))
792 		return (HZ / 9); /* ~110 ms */
793 
794 	return (HZ / 16); /* ~60 ms */
795 }
796 
797 static void ath_chanctx_switch(struct ath_softc *sc, struct ath_chanctx *ctx,
798 			       struct cfg80211_chan_def *chandef)
799 {
800 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
801 
802 	spin_lock_bh(&sc->chan_lock);
803 
804 	if (test_bit(ATH_OP_MULTI_CHANNEL, &common->op_flags) &&
805 	    (sc->cur_chan != ctx) && (ctx == &sc->offchannel.chan)) {
806 		if (chandef)
807 			ctx->chandef = *chandef;
808 
809 		sc->sched.offchannel_pending = true;
810 		sc->sched.wait_switch = true;
811 		sc->sched.offchannel_duration =
812 			jiffies_to_usecs(sc->offchannel.duration) +
813 			sc->sched.channel_switch_time;
814 
815 		spin_unlock_bh(&sc->chan_lock);
816 		ath_dbg(common, CHAN_CTX,
817 			"Set offchannel_pending to true\n");
818 		return;
819 	}
820 
821 	sc->next_chan = ctx;
822 	if (chandef) {
823 		ctx->chandef = *chandef;
824 		ath_dbg(common, CHAN_CTX,
825 			"Assigned next_chan to %d MHz\n", chandef->center_freq1);
826 	}
827 
828 	if (sc->next_chan == &sc->offchannel.chan) {
829 		sc->sched.offchannel_duration =
830 			jiffies_to_usecs(sc->offchannel.duration) +
831 			sc->sched.channel_switch_time;
832 
833 		if (chandef) {
834 			ath_dbg(common, CHAN_CTX,
835 				"Offchannel duration for chan %d MHz : %u\n",
836 				chandef->center_freq1,
837 				sc->sched.offchannel_duration);
838 		}
839 	}
840 	spin_unlock_bh(&sc->chan_lock);
841 	ieee80211_queue_work(sc->hw, &sc->chanctx_work);
842 }
843 
844 static void ath_chanctx_offchan_switch(struct ath_softc *sc,
845 				       struct ieee80211_channel *chan)
846 {
847 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
848 	struct cfg80211_chan_def chandef;
849 
850 	cfg80211_chandef_create(&chandef, chan, NL80211_CHAN_NO_HT);
851 	ath_dbg(common, CHAN_CTX,
852 		"Channel definition created: %d MHz\n", chandef.center_freq1);
853 
854 	ath_chanctx_switch(sc, &sc->offchannel.chan, &chandef);
855 }
856 
857 static struct ath_chanctx *ath_chanctx_get_oper_chan(struct ath_softc *sc,
858 						     bool active)
859 {
860 	struct ath_chanctx *ctx;
861 
862 	ath_for_each_chanctx(sc, ctx) {
863 		if (!ctx->assigned || list_empty(&ctx->vifs))
864 			continue;
865 		if (active && !ctx->active)
866 			continue;
867 
868 		if (ctx->switch_after_beacon)
869 			return ctx;
870 	}
871 
872 	return &sc->chanctx[0];
873 }
874 
875 static void
876 ath_scan_next_channel(struct ath_softc *sc)
877 {
878 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
879 	struct cfg80211_scan_request *req = sc->offchannel.scan_req;
880 	struct ieee80211_channel *chan;
881 
882 	if (sc->offchannel.scan_idx >= req->n_channels) {
883 		ath_dbg(common, CHAN_CTX,
884 			"Moving offchannel state to ATH_OFFCHANNEL_IDLE, "
885 			"scan_idx: %d, n_channels: %d\n",
886 			sc->offchannel.scan_idx,
887 			req->n_channels);
888 
889 		sc->offchannel.state = ATH_OFFCHANNEL_IDLE;
890 		ath_chanctx_switch(sc, ath_chanctx_get_oper_chan(sc, false),
891 				   NULL);
892 		return;
893 	}
894 
895 	ath_dbg(common, CHAN_CTX,
896 		"Moving offchannel state to ATH_OFFCHANNEL_PROBE_SEND, scan_idx: %d\n",
897 		sc->offchannel.scan_idx);
898 
899 	chan = req->channels[sc->offchannel.scan_idx++];
900 	sc->offchannel.duration = ath_scan_channel_duration(sc, chan);
901 	sc->offchannel.state = ATH_OFFCHANNEL_PROBE_SEND;
902 
903 	ath_chanctx_offchan_switch(sc, chan);
904 }
905 
906 void ath_offchannel_next(struct ath_softc *sc)
907 {
908 	struct ieee80211_vif *vif;
909 
910 	if (sc->offchannel.scan_req) {
911 		vif = sc->offchannel.scan_vif;
912 		sc->offchannel.chan.txpower = vif->bss_conf.txpower;
913 		ath_scan_next_channel(sc);
914 	} else if (sc->offchannel.roc_vif) {
915 		vif = sc->offchannel.roc_vif;
916 		sc->offchannel.chan.txpower = vif->bss_conf.txpower;
917 		sc->offchannel.duration =
918 			msecs_to_jiffies(sc->offchannel.roc_duration);
919 		sc->offchannel.state = ATH_OFFCHANNEL_ROC_START;
920 		ath_chanctx_offchan_switch(sc, sc->offchannel.roc_chan);
921 	} else {
922 		spin_lock_bh(&sc->chan_lock);
923 		sc->sched.offchannel_pending = false;
924 		sc->sched.wait_switch = false;
925 		spin_unlock_bh(&sc->chan_lock);
926 
927 		ath_chanctx_switch(sc, ath_chanctx_get_oper_chan(sc, false),
928 				   NULL);
929 		sc->offchannel.state = ATH_OFFCHANNEL_IDLE;
930 		if (sc->ps_idle)
931 			ath_cancel_work(sc);
932 	}
933 }
934 
935 void ath_roc_complete(struct ath_softc *sc, enum ath_roc_complete_reason reason)
936 {
937 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
938 
939 	sc->offchannel.roc_vif = NULL;
940 	sc->offchannel.roc_chan = NULL;
941 
942 	switch (reason) {
943 	case ATH_ROC_COMPLETE_ABORT:
944 		ath_dbg(common, CHAN_CTX, "RoC aborted\n");
945 		ieee80211_remain_on_channel_expired(sc->hw);
946 		break;
947 	case ATH_ROC_COMPLETE_EXPIRE:
948 		ath_dbg(common, CHAN_CTX, "RoC expired\n");
949 		ieee80211_remain_on_channel_expired(sc->hw);
950 		break;
951 	case ATH_ROC_COMPLETE_CANCEL:
952 		ath_dbg(common, CHAN_CTX, "RoC canceled\n");
953 		break;
954 	}
955 
956 	ath_offchannel_next(sc);
957 	ath9k_ps_restore(sc);
958 }
959 
960 void ath_scan_complete(struct ath_softc *sc, bool abort)
961 {
962 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
963 
964 	if (abort)
965 		ath_dbg(common, CHAN_CTX, "HW scan aborted\n");
966 	else
967 		ath_dbg(common, CHAN_CTX, "HW scan complete\n");
968 
969 	sc->offchannel.scan_req = NULL;
970 	sc->offchannel.scan_vif = NULL;
971 	sc->offchannel.state = ATH_OFFCHANNEL_IDLE;
972 	ieee80211_scan_completed(sc->hw, abort);
973 	clear_bit(ATH_OP_SCANNING, &common->op_flags);
974 	spin_lock_bh(&sc->chan_lock);
975 	if (test_bit(ATH_OP_MULTI_CHANNEL, &common->op_flags))
976 		sc->sched.force_noa_update = true;
977 	spin_unlock_bh(&sc->chan_lock);
978 	ath_offchannel_next(sc);
979 	ath9k_ps_restore(sc);
980 }
981 
982 static void ath_scan_send_probe(struct ath_softc *sc,
983 				struct cfg80211_ssid *ssid)
984 {
985 	struct cfg80211_scan_request *req = sc->offchannel.scan_req;
986 	struct ieee80211_vif *vif = sc->offchannel.scan_vif;
987 	struct ath_tx_control txctl = {};
988 	struct sk_buff *skb;
989 	struct ieee80211_tx_info *info;
990 	int band = sc->offchannel.chan.chandef.chan->band;
991 
992 	skb = ieee80211_probereq_get(sc->hw, vif->addr,
993 			ssid->ssid, ssid->ssid_len, req->ie_len);
994 	if (!skb)
995 		return;
996 
997 	info = IEEE80211_SKB_CB(skb);
998 	if (req->no_cck)
999 		info->flags |= IEEE80211_TX_CTL_NO_CCK_RATE;
1000 
1001 	if (req->ie_len)
1002 		memcpy(skb_put(skb, req->ie_len), req->ie, req->ie_len);
1003 
1004 	skb_set_queue_mapping(skb, IEEE80211_AC_VO);
1005 
1006 	if (!ieee80211_tx_prepare_skb(sc->hw, vif, skb, band, NULL))
1007 		goto error;
1008 
1009 	txctl.txq = sc->tx.txq_map[IEEE80211_AC_VO];
1010 	txctl.force_channel = true;
1011 	if (ath_tx_start(sc->hw, skb, &txctl))
1012 		goto error;
1013 
1014 	return;
1015 
1016 error:
1017 	ieee80211_free_txskb(sc->hw, skb);
1018 }
1019 
1020 static void ath_scan_channel_start(struct ath_softc *sc)
1021 {
1022 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
1023 	struct cfg80211_scan_request *req = sc->offchannel.scan_req;
1024 	int i;
1025 
1026 	if (!(sc->cur_chan->chandef.chan->flags & IEEE80211_CHAN_NO_IR) &&
1027 	    req->n_ssids) {
1028 		for (i = 0; i < req->n_ssids; i++)
1029 			ath_scan_send_probe(sc, &req->ssids[i]);
1030 
1031 	}
1032 
1033 	ath_dbg(common, CHAN_CTX,
1034 		"Moving offchannel state to ATH_OFFCHANNEL_PROBE_WAIT\n");
1035 
1036 	sc->offchannel.state = ATH_OFFCHANNEL_PROBE_WAIT;
1037 	mod_timer(&sc->offchannel.timer, jiffies + sc->offchannel.duration);
1038 }
1039 
1040 static void ath_chanctx_timer(unsigned long data)
1041 {
1042 	struct ath_softc *sc = (struct ath_softc *) data;
1043 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
1044 
1045 	ath_dbg(common, CHAN_CTX,
1046 		"Channel context timer invoked\n");
1047 
1048 	ath_chanctx_event(sc, NULL, ATH_CHANCTX_EVENT_TSF_TIMER);
1049 }
1050 
1051 static void ath_offchannel_timer(unsigned long data)
1052 {
1053 	struct ath_softc *sc = (struct ath_softc *)data;
1054 	struct ath_chanctx *ctx;
1055 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
1056 
1057 	ath_dbg(common, CHAN_CTX, "%s: offchannel state: %s\n",
1058 		__func__, offchannel_state_string(sc->offchannel.state));
1059 
1060 	switch (sc->offchannel.state) {
1061 	case ATH_OFFCHANNEL_PROBE_WAIT:
1062 		if (!sc->offchannel.scan_req)
1063 			return;
1064 
1065 		/* get first active channel context */
1066 		ctx = ath_chanctx_get_oper_chan(sc, true);
1067 		if (ctx->active) {
1068 			ath_dbg(common, CHAN_CTX,
1069 				"Switch to oper/active context, "
1070 				"move offchannel state to ATH_OFFCHANNEL_SUSPEND\n");
1071 
1072 			sc->offchannel.state = ATH_OFFCHANNEL_SUSPEND;
1073 			ath_chanctx_switch(sc, ctx, NULL);
1074 			mod_timer(&sc->offchannel.timer, jiffies + HZ / 10);
1075 			break;
1076 		}
1077 		/* fall through */
1078 	case ATH_OFFCHANNEL_SUSPEND:
1079 		if (!sc->offchannel.scan_req)
1080 			return;
1081 
1082 		ath_scan_next_channel(sc);
1083 		break;
1084 	case ATH_OFFCHANNEL_ROC_START:
1085 	case ATH_OFFCHANNEL_ROC_WAIT:
1086 		sc->offchannel.state = ATH_OFFCHANNEL_ROC_DONE;
1087 		ath_roc_complete(sc, ATH_ROC_COMPLETE_EXPIRE);
1088 		break;
1089 	default:
1090 		break;
1091 	}
1092 }
1093 
1094 static bool
1095 ath_chanctx_send_vif_ps_frame(struct ath_softc *sc, struct ath_vif *avp,
1096 			      bool powersave)
1097 {
1098 	struct ieee80211_vif *vif = avp->vif;
1099 	struct ieee80211_sta *sta = NULL;
1100 	struct ieee80211_hdr_3addr *nullfunc;
1101 	struct ath_tx_control txctl;
1102 	struct sk_buff *skb;
1103 	int band = sc->cur_chan->chandef.chan->band;
1104 
1105 	switch (vif->type) {
1106 	case NL80211_IFTYPE_STATION:
1107 		if (!avp->assoc)
1108 			return false;
1109 
1110 		skb = ieee80211_nullfunc_get(sc->hw, vif);
1111 		if (!skb)
1112 			return false;
1113 
1114 		nullfunc = (struct ieee80211_hdr_3addr *) skb->data;
1115 		if (powersave)
1116 			nullfunc->frame_control |=
1117 				cpu_to_le16(IEEE80211_FCTL_PM);
1118 
1119 		skb->priority = 7;
1120 		skb_set_queue_mapping(skb, IEEE80211_AC_VO);
1121 		if (!ieee80211_tx_prepare_skb(sc->hw, vif, skb, band, &sta)) {
1122 			dev_kfree_skb_any(skb);
1123 			return false;
1124 		}
1125 		break;
1126 	default:
1127 		return false;
1128 	}
1129 
1130 	memset(&txctl, 0, sizeof(txctl));
1131 	txctl.txq = sc->tx.txq_map[IEEE80211_AC_VO];
1132 	txctl.sta = sta;
1133 	txctl.force_channel = true;
1134 	if (ath_tx_start(sc->hw, skb, &txctl)) {
1135 		ieee80211_free_txskb(sc->hw, skb);
1136 		return false;
1137 	}
1138 
1139 	return true;
1140 }
1141 
1142 static bool
1143 ath_chanctx_send_ps_frame(struct ath_softc *sc, bool powersave)
1144 {
1145 	struct ath_vif *avp;
1146 	bool sent = false;
1147 
1148 	rcu_read_lock();
1149 	list_for_each_entry(avp, &sc->cur_chan->vifs, list) {
1150 		if (ath_chanctx_send_vif_ps_frame(sc, avp, powersave))
1151 			sent = true;
1152 	}
1153 	rcu_read_unlock();
1154 
1155 	return sent;
1156 }
1157 
1158 static bool ath_chanctx_defer_switch(struct ath_softc *sc)
1159 {
1160 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
1161 
1162 	if (sc->cur_chan == &sc->offchannel.chan)
1163 		return false;
1164 
1165 	switch (sc->sched.state) {
1166 	case ATH_CHANCTX_STATE_SWITCH:
1167 		return false;
1168 	case ATH_CHANCTX_STATE_IDLE:
1169 		if (!sc->cur_chan->switch_after_beacon)
1170 			return false;
1171 
1172 		ath_dbg(common, CHAN_CTX,
1173 			"Defer switch, set chanctx state to WAIT_FOR_BEACON\n");
1174 
1175 		sc->sched.state = ATH_CHANCTX_STATE_WAIT_FOR_BEACON;
1176 		break;
1177 	default:
1178 		break;
1179 	}
1180 
1181 	return true;
1182 }
1183 
1184 static void ath_offchannel_channel_change(struct ath_softc *sc)
1185 {
1186 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
1187 
1188 	ath_dbg(common, CHAN_CTX, "%s: offchannel state: %s\n",
1189 		__func__, offchannel_state_string(sc->offchannel.state));
1190 
1191 	switch (sc->offchannel.state) {
1192 	case ATH_OFFCHANNEL_PROBE_SEND:
1193 		if (!sc->offchannel.scan_req)
1194 			return;
1195 
1196 		if (sc->cur_chan->chandef.chan !=
1197 		    sc->offchannel.chan.chandef.chan)
1198 			return;
1199 
1200 		ath_scan_channel_start(sc);
1201 		break;
1202 	case ATH_OFFCHANNEL_IDLE:
1203 		if (!sc->offchannel.scan_req)
1204 			return;
1205 
1206 		ath_scan_complete(sc, false);
1207 		break;
1208 	case ATH_OFFCHANNEL_ROC_START:
1209 		if (sc->cur_chan != &sc->offchannel.chan)
1210 			break;
1211 
1212 		sc->offchannel.state = ATH_OFFCHANNEL_ROC_WAIT;
1213 		mod_timer(&sc->offchannel.timer,
1214 			  jiffies + sc->offchannel.duration);
1215 		ieee80211_ready_on_channel(sc->hw);
1216 		break;
1217 	case ATH_OFFCHANNEL_ROC_DONE:
1218 		break;
1219 	default:
1220 		break;
1221 	}
1222 }
1223 
1224 void ath_chanctx_set_next(struct ath_softc *sc, bool force)
1225 {
1226 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
1227 	struct ath_chanctx *old_ctx;
1228 	struct timespec ts;
1229 	bool measure_time = false;
1230 	bool send_ps = false;
1231 	bool queues_stopped = false;
1232 
1233 	spin_lock_bh(&sc->chan_lock);
1234 	if (!sc->next_chan) {
1235 		spin_unlock_bh(&sc->chan_lock);
1236 		return;
1237 	}
1238 
1239 	if (!force && ath_chanctx_defer_switch(sc)) {
1240 		spin_unlock_bh(&sc->chan_lock);
1241 		return;
1242 	}
1243 
1244 	ath_dbg(common, CHAN_CTX,
1245 		"%s: current: %d MHz, next: %d MHz\n",
1246 		__func__,
1247 		sc->cur_chan->chandef.center_freq1,
1248 		sc->next_chan->chandef.center_freq1);
1249 
1250 	if (sc->cur_chan != sc->next_chan) {
1251 		ath_dbg(common, CHAN_CTX,
1252 			"Stopping current chanctx: %d\n",
1253 			sc->cur_chan->chandef.center_freq1);
1254 		sc->cur_chan->stopped = true;
1255 		spin_unlock_bh(&sc->chan_lock);
1256 
1257 		if (sc->next_chan == &sc->offchannel.chan) {
1258 			getrawmonotonic(&ts);
1259 			measure_time = true;
1260 		}
1261 
1262 		ath9k_chanctx_stop_queues(sc, sc->cur_chan);
1263 		queues_stopped = true;
1264 
1265 		__ath9k_flush(sc->hw, ~0, true, false, false);
1266 
1267 		if (ath_chanctx_send_ps_frame(sc, true))
1268 			__ath9k_flush(sc->hw, BIT(IEEE80211_AC_VO),
1269 				      false, false, false);
1270 
1271 		send_ps = true;
1272 		spin_lock_bh(&sc->chan_lock);
1273 
1274 		if (sc->cur_chan != &sc->offchannel.chan) {
1275 			getrawmonotonic(&sc->cur_chan->tsf_ts);
1276 			sc->cur_chan->tsf_val = ath9k_hw_gettsf64(sc->sc_ah);
1277 		}
1278 	}
1279 	old_ctx = sc->cur_chan;
1280 	sc->cur_chan = sc->next_chan;
1281 	sc->cur_chan->stopped = false;
1282 	sc->next_chan = NULL;
1283 
1284 	if (!sc->sched.offchannel_pending)
1285 		sc->sched.offchannel_duration = 0;
1286 
1287 	if (sc->sched.state != ATH_CHANCTX_STATE_FORCE_ACTIVE)
1288 		sc->sched.state = ATH_CHANCTX_STATE_IDLE;
1289 
1290 	spin_unlock_bh(&sc->chan_lock);
1291 
1292 	if (sc->sc_ah->chip_fullsleep ||
1293 	    memcmp(&sc->cur_chandef, &sc->cur_chan->chandef,
1294 		   sizeof(sc->cur_chandef))) {
1295 		ath_dbg(common, CHAN_CTX,
1296 			"%s: Set channel %d MHz\n",
1297 			__func__, sc->cur_chan->chandef.center_freq1);
1298 		ath_set_channel(sc);
1299 		if (measure_time)
1300 			sc->sched.channel_switch_time =
1301 				ath9k_hw_get_tsf_offset(&ts, NULL);
1302 		/*
1303 		 * A reset will ensure that all queues are woken up,
1304 		 * so there is no need to awaken them again.
1305 		 */
1306 		goto out;
1307 	}
1308 
1309 	if (queues_stopped)
1310 		ath9k_chanctx_wake_queues(sc, old_ctx);
1311 out:
1312 	if (send_ps)
1313 		ath_chanctx_send_ps_frame(sc, false);
1314 
1315 	ath_offchannel_channel_change(sc);
1316 	ath_chanctx_event(sc, NULL, ATH_CHANCTX_EVENT_SWITCH);
1317 }
1318 
1319 static void ath_chanctx_work(struct work_struct *work)
1320 {
1321 	struct ath_softc *sc = container_of(work, struct ath_softc,
1322 					    chanctx_work);
1323 	mutex_lock(&sc->mutex);
1324 	ath_chanctx_set_next(sc, false);
1325 	mutex_unlock(&sc->mutex);
1326 }
1327 
1328 void ath9k_offchannel_init(struct ath_softc *sc)
1329 {
1330 	struct ath_chanctx *ctx;
1331 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
1332 	struct ieee80211_supported_band *sband;
1333 	struct ieee80211_channel *chan;
1334 	int i;
1335 
1336 	sband = &common->sbands[NL80211_BAND_2GHZ];
1337 	if (!sband->n_channels)
1338 		sband = &common->sbands[NL80211_BAND_5GHZ];
1339 
1340 	chan = &sband->channels[0];
1341 
1342 	ctx = &sc->offchannel.chan;
1343 	INIT_LIST_HEAD(&ctx->vifs);
1344 	ctx->txpower = ATH_TXPOWER_MAX;
1345 	cfg80211_chandef_create(&ctx->chandef, chan, NL80211_CHAN_HT20);
1346 
1347 	for (i = 0; i < ARRAY_SIZE(ctx->acq); i++)
1348 		INIT_LIST_HEAD(&ctx->acq[i]);
1349 
1350 	sc->offchannel.chan.offchannel = true;
1351 }
1352 
1353 void ath9k_init_channel_context(struct ath_softc *sc)
1354 {
1355 	INIT_WORK(&sc->chanctx_work, ath_chanctx_work);
1356 
1357 	setup_timer(&sc->offchannel.timer, ath_offchannel_timer,
1358 		    (unsigned long)sc);
1359 	setup_timer(&sc->sched.timer, ath_chanctx_timer,
1360 		    (unsigned long)sc);
1361 
1362 	init_completion(&sc->go_beacon);
1363 }
1364 
1365 void ath9k_deinit_channel_context(struct ath_softc *sc)
1366 {
1367 	cancel_work_sync(&sc->chanctx_work);
1368 }
1369 
1370 bool ath9k_is_chanctx_enabled(void)
1371 {
1372 	return (ath9k_use_chanctx == 1);
1373 }
1374 
1375 /********************/
1376 /* Queue management */
1377 /********************/
1378 
1379 void ath9k_chanctx_stop_queues(struct ath_softc *sc, struct ath_chanctx *ctx)
1380 {
1381 	struct ath_hw *ah = sc->sc_ah;
1382 	int i;
1383 
1384 	if (ctx == &sc->offchannel.chan) {
1385 		ieee80211_stop_queue(sc->hw,
1386 				     sc->hw->offchannel_tx_hw_queue);
1387 	} else {
1388 		for (i = 0; i < IEEE80211_NUM_ACS; i++)
1389 			ieee80211_stop_queue(sc->hw,
1390 					     ctx->hw_queue_base + i);
1391 	}
1392 
1393 	if (ah->opmode == NL80211_IFTYPE_AP)
1394 		ieee80211_stop_queue(sc->hw, sc->hw->queues - 2);
1395 }
1396 
1397 
1398 void ath9k_chanctx_wake_queues(struct ath_softc *sc, struct ath_chanctx *ctx)
1399 {
1400 	struct ath_hw *ah = sc->sc_ah;
1401 	int i;
1402 
1403 	if (ctx == &sc->offchannel.chan) {
1404 		ieee80211_wake_queue(sc->hw,
1405 				     sc->hw->offchannel_tx_hw_queue);
1406 	} else {
1407 		for (i = 0; i < IEEE80211_NUM_ACS; i++)
1408 			ieee80211_wake_queue(sc->hw,
1409 					     ctx->hw_queue_base + i);
1410 	}
1411 
1412 	if (ah->opmode == NL80211_IFTYPE_AP)
1413 		ieee80211_wake_queue(sc->hw, sc->hw->queues - 2);
1414 }
1415 
1416 /*****************/
1417 /* P2P Powersave */
1418 /*****************/
1419 
1420 static void ath9k_update_p2p_ps_timer(struct ath_softc *sc, struct ath_vif *avp)
1421 {
1422 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
1423 	struct ath_hw *ah = sc->sc_ah;
1424 	u32 tsf, target_tsf;
1425 
1426 	if (!avp || !avp->noa.has_next_tsf)
1427 		return;
1428 
1429 	ath9k_hw_gen_timer_stop(ah, sc->p2p_ps_timer);
1430 
1431 	tsf = ath9k_hw_gettsf32(sc->sc_ah);
1432 
1433 	target_tsf = avp->noa.next_tsf;
1434 	if (!avp->noa.absent)
1435 		target_tsf -= ATH_P2P_PS_STOP_TIME;
1436 	else
1437 		target_tsf += ATH_P2P_PS_STOP_TIME;
1438 
1439 	if (target_tsf - tsf < ATH_P2P_PS_STOP_TIME)
1440 		target_tsf = tsf + ATH_P2P_PS_STOP_TIME;
1441 
1442 	ath_dbg(common, CHAN_CTX, "%s absent %d tsf 0x%08X next_tsf 0x%08X (%dms)\n",
1443 		__func__, avp->noa.absent, tsf, target_tsf,
1444 		(target_tsf - tsf) / 1000);
1445 
1446 	ath9k_hw_gen_timer_start(ah, sc->p2p_ps_timer, target_tsf, 1000000);
1447 }
1448 
1449 static void ath9k_update_p2p_ps(struct ath_softc *sc, struct ieee80211_vif *vif)
1450 {
1451 	struct ath_vif *avp = (void *)vif->drv_priv;
1452 	u32 tsf;
1453 
1454 	if (!sc->p2p_ps_timer)
1455 		return;
1456 
1457 	if (vif->type != NL80211_IFTYPE_STATION)
1458 		return;
1459 
1460 	sc->p2p_ps_vif = avp;
1461 
1462 	if (sc->ps_flags & PS_BEACON_SYNC)
1463 		return;
1464 
1465 	tsf = ath9k_hw_gettsf32(sc->sc_ah);
1466 	ieee80211_parse_p2p_noa(&vif->bss_conf.p2p_noa_attr, &avp->noa, tsf);
1467 	ath9k_update_p2p_ps_timer(sc, avp);
1468 }
1469 
1470 static u8 ath9k_get_ctwin(struct ath_softc *sc, struct ath_vif *avp)
1471 {
1472 	struct ath_beacon_config *cur_conf = &sc->cur_chan->beacon;
1473 	u8 switch_time, ctwin;
1474 
1475 	/*
1476 	 * Channel switch in multi-channel mode is deferred
1477 	 * by a quarter beacon interval when handling
1478 	 * ATH_CHANCTX_EVENT_BEACON_PREPARE, so the P2P-GO
1479 	 * interface is guaranteed to be discoverable
1480 	 * for that duration after a TBTT.
1481 	 */
1482 	switch_time = cur_conf->beacon_interval / 4;
1483 
1484 	ctwin = avp->vif->bss_conf.p2p_noa_attr.oppps_ctwindow;
1485 	if (ctwin && (ctwin < switch_time))
1486 		return ctwin;
1487 
1488 	if (switch_time < P2P_DEFAULT_CTWIN)
1489 		return 0;
1490 
1491 	return P2P_DEFAULT_CTWIN;
1492 }
1493 
1494 void ath9k_beacon_add_noa(struct ath_softc *sc, struct ath_vif *avp,
1495 			  struct sk_buff *skb)
1496 {
1497 	static const u8 noa_ie_hdr[] = {
1498 		WLAN_EID_VENDOR_SPECIFIC,	/* type */
1499 		0,				/* length */
1500 		0x50, 0x6f, 0x9a,		/* WFA OUI */
1501 		0x09,				/* P2P subtype */
1502 		0x0c,				/* Notice of Absence */
1503 		0x00,				/* LSB of little-endian len */
1504 		0x00,				/* MSB of little-endian len */
1505 	};
1506 
1507 	struct ieee80211_p2p_noa_attr *noa;
1508 	int noa_len, noa_desc, i = 0;
1509 	u8 *hdr;
1510 
1511 	if (!avp->offchannel_duration && !avp->noa_duration)
1512 		return;
1513 
1514 	noa_desc = !!avp->offchannel_duration + !!avp->noa_duration;
1515 	noa_len = 2 + sizeof(struct ieee80211_p2p_noa_desc) * noa_desc;
1516 
1517 	hdr = skb_put(skb, sizeof(noa_ie_hdr));
1518 	memcpy(hdr, noa_ie_hdr, sizeof(noa_ie_hdr));
1519 	hdr[1] = sizeof(noa_ie_hdr) + noa_len - 2;
1520 	hdr[7] = noa_len;
1521 
1522 	noa = (void *) skb_put(skb, noa_len);
1523 	memset(noa, 0, noa_len);
1524 
1525 	noa->index = avp->noa_index;
1526 	noa->oppps_ctwindow = ath9k_get_ctwin(sc, avp);
1527 	if (noa->oppps_ctwindow)
1528 		noa->oppps_ctwindow |= BIT(7);
1529 
1530 	if (avp->noa_duration) {
1531 		if (avp->periodic_noa) {
1532 			u32 interval = TU_TO_USEC(sc->cur_chan->beacon.beacon_interval);
1533 			noa->desc[i].count = 255;
1534 			noa->desc[i].interval = cpu_to_le32(interval);
1535 		} else {
1536 			noa->desc[i].count = 1;
1537 		}
1538 
1539 		noa->desc[i].start_time = cpu_to_le32(avp->noa_start);
1540 		noa->desc[i].duration = cpu_to_le32(avp->noa_duration);
1541 		i++;
1542 	}
1543 
1544 	if (avp->offchannel_duration) {
1545 		noa->desc[i].count = 1;
1546 		noa->desc[i].start_time = cpu_to_le32(avp->offchannel_start);
1547 		noa->desc[i].duration = cpu_to_le32(avp->offchannel_duration);
1548 	}
1549 }
1550 
1551 void ath9k_p2p_ps_timer(void *priv)
1552 {
1553 	struct ath_softc *sc = priv;
1554 	struct ath_vif *avp = sc->p2p_ps_vif;
1555 	struct ieee80211_vif *vif;
1556 	struct ieee80211_sta *sta;
1557 	struct ath_node *an;
1558 	u32 tsf;
1559 
1560 	del_timer_sync(&sc->sched.timer);
1561 	ath9k_hw_gen_timer_stop(sc->sc_ah, sc->p2p_ps_timer);
1562 	ath_chanctx_event(sc, NULL, ATH_CHANCTX_EVENT_TSF_TIMER);
1563 
1564 	if (!avp || avp->chanctx != sc->cur_chan)
1565 		return;
1566 
1567 	tsf = ath9k_hw_gettsf32(sc->sc_ah);
1568 	if (!avp->noa.absent)
1569 		tsf += ATH_P2P_PS_STOP_TIME;
1570 	else
1571 		tsf -= ATH_P2P_PS_STOP_TIME;
1572 
1573 	if (!avp->noa.has_next_tsf ||
1574 	    avp->noa.next_tsf - tsf > BIT(31))
1575 		ieee80211_update_p2p_noa(&avp->noa, tsf);
1576 
1577 	ath9k_update_p2p_ps_timer(sc, avp);
1578 
1579 	rcu_read_lock();
1580 
1581 	vif = avp->vif;
1582 	sta = ieee80211_find_sta(vif, avp->bssid);
1583 	if (!sta)
1584 		goto out;
1585 
1586 	an = (void *) sta->drv_priv;
1587 	if (an->sleeping == !!avp->noa.absent)
1588 		goto out;
1589 
1590 	an->sleeping = avp->noa.absent;
1591 	if (an->sleeping)
1592 		ath_tx_aggr_sleep(sta, sc, an);
1593 	else
1594 		ath_tx_aggr_wakeup(sc, an);
1595 
1596 out:
1597 	rcu_read_unlock();
1598 }
1599 
1600 void ath9k_p2p_bss_info_changed(struct ath_softc *sc,
1601 				struct ieee80211_vif *vif)
1602 {
1603 	unsigned long flags;
1604 
1605 	spin_lock_bh(&sc->sc_pcu_lock);
1606 	spin_lock_irqsave(&sc->sc_pm_lock, flags);
1607 	ath9k_update_p2p_ps(sc, vif);
1608 	spin_unlock_irqrestore(&sc->sc_pm_lock, flags);
1609 	spin_unlock_bh(&sc->sc_pcu_lock);
1610 }
1611 
1612 void ath9k_p2p_beacon_sync(struct ath_softc *sc)
1613 {
1614 	if (sc->p2p_ps_vif)
1615 		ath9k_update_p2p_ps(sc, sc->p2p_ps_vif->vif);
1616 }
1617 
1618 void ath9k_p2p_remove_vif(struct ath_softc *sc,
1619 			  struct ieee80211_vif *vif)
1620 {
1621 	struct ath_vif *avp = (void *)vif->drv_priv;
1622 
1623 	spin_lock_bh(&sc->sc_pcu_lock);
1624 	if (avp == sc->p2p_ps_vif) {
1625 		sc->p2p_ps_vif = NULL;
1626 		ath9k_update_p2p_ps_timer(sc, NULL);
1627 	}
1628 	spin_unlock_bh(&sc->sc_pcu_lock);
1629 }
1630 
1631 int ath9k_init_p2p(struct ath_softc *sc)
1632 {
1633 	sc->p2p_ps_timer = ath_gen_timer_alloc(sc->sc_ah, ath9k_p2p_ps_timer,
1634 					       NULL, sc, AR_FIRST_NDP_TIMER);
1635 	if (!sc->p2p_ps_timer)
1636 		return -ENOMEM;
1637 
1638 	return 0;
1639 }
1640 
1641 void ath9k_deinit_p2p(struct ath_softc *sc)
1642 {
1643 	if (sc->p2p_ps_timer)
1644 		ath_gen_timer_free(sc->sc_ah, sc->p2p_ps_timer);
1645 }
1646 
1647 #endif /* CONFIG_ATH9K_CHANNEL_CONTEXT */
1648