drivers/net/wireless/ath/ath9k/channel.c

   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_internal(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                 /* set HW specific DFS configuration */
  87                 ath9k_hw_set_radar_params(ah);
  88                 rxfilter = ath9k_hw_getrxfilter(ah);
  89                 rxfilter |= ATH9K_RX_FILTER_PHYRADAR |
  90                                 ATH9K_RX_FILTER_PHYERR;
  91                 ath9k_hw_setrxfilter(ah, rxfilter);
  92                 ath_dbg(common, DFS, "DFS enabled at freq %d\n",
  93                         chan->center_freq);
  94         } else {
  95                 /* perform spectral scan if requested. */
  96                 if (test_bit(ATH_OP_SCANNING, &common->op_flags) &&
  97                         sc->spectral_mode == SPECTRAL_CHANSCAN)
  98                         ath9k_spectral_scan_trigger(hw);
  99         }
 100
 101         return 0;
 102 }
 103
 104 void ath_chanctx_init(struct ath_softc *sc)
 105 {
 106         struct ath_chanctx *ctx;
 107         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 108         struct ieee80211_supported_band *sband;
 109         struct ieee80211_channel *chan;
 110         int i, j;
 111
 112         sband = &common->sbands[IEEE80211_BAND_2GHZ];
 113         if (!sband->n_channels)
 114                 sband = &common->sbands[IEEE80211_BAND_5GHZ];
 115
 116         chan = &sband->channels[0];
 117         for (i = 0; i < ATH9K_NUM_CHANCTX; i++) {
 118                 ctx = &sc->chanctx[i];
 119                 cfg80211_chandef_create(&ctx->chandef, chan, NL80211_CHAN_HT20);
 120                 INIT_LIST_HEAD(&ctx->vifs);
 121                 ctx->txpower = ATH_TXPOWER_MAX;
 122                 for (j = 0; j < ARRAY_SIZE(ctx->acq); j++)
 123                         INIT_LIST_HEAD(&ctx->acq[j]);
 124         }
 125 }
 126
 127 void ath_chanctx_set_channel(struct ath_softc *sc, struct ath_chanctx *ctx,
 128                              struct cfg80211_chan_def *chandef)
 129 {
 130         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 131         bool cur_chan;
 132
 133         spin_lock_bh(&sc->chan_lock);
 134         if (chandef)
 135                 memcpy(&ctx->chandef, chandef, sizeof(*chandef));
 136         cur_chan = sc->cur_chan == ctx;
 137         spin_unlock_bh(&sc->chan_lock);
 138
 139         if (!cur_chan) {
 140                 ath_dbg(common, CHAN_CTX,
 141                         "Current context differs from the new context\n");
 142                 return;
 143         }
 144
 145         ath_set_channel(sc);
 146 }
 147
 148 #ifdef CONFIG_ATH9K_CHANNEL_CONTEXT
 149
 150 /**********************************************************/
 151 /* Functions to handle the channel context state machine. */
 152 /**********************************************************/
 153
 154 static const char *offchannel_state_string(enum ath_offchannel_state state)
 155 {
 156         switch (state) {
 157                 case_rtn_string(ATH_OFFCHANNEL_IDLE);
 158                 case_rtn_string(ATH_OFFCHANNEL_PROBE_SEND);
 159                 case_rtn_string(ATH_OFFCHANNEL_PROBE_WAIT);
 160                 case_rtn_string(ATH_OFFCHANNEL_SUSPEND);
 161                 case_rtn_string(ATH_OFFCHANNEL_ROC_START);
 162                 case_rtn_string(ATH_OFFCHANNEL_ROC_WAIT);
 163                 case_rtn_string(ATH_OFFCHANNEL_ROC_DONE);
 164         default:
 165                 return "unknown";
 166         }
 167 }
 168
 169 static const char *chanctx_event_string(enum ath_chanctx_event ev)
 170 {
 171         switch (ev) {
 172                 case_rtn_string(ATH_CHANCTX_EVENT_BEACON_PREPARE);
 173                 case_rtn_string(ATH_CHANCTX_EVENT_BEACON_SENT);
 174                 case_rtn_string(ATH_CHANCTX_EVENT_TSF_TIMER);
 175                 case_rtn_string(ATH_CHANCTX_EVENT_BEACON_RECEIVED);
 176                 case_rtn_string(ATH_CHANCTX_EVENT_ASSOC);
 177                 case_rtn_string(ATH_CHANCTX_EVENT_SWITCH);
 178                 case_rtn_string(ATH_CHANCTX_EVENT_ASSIGN);
 179                 case_rtn_string(ATH_CHANCTX_EVENT_UNASSIGN);
 180                 case_rtn_string(ATH_CHANCTX_EVENT_CHANGE);
 181                 case_rtn_string(ATH_CHANCTX_EVENT_ENABLE_MULTICHANNEL);
 182         default:
 183                 return "unknown";
 184         }
 185 }
 186
 187 static const char *chanctx_state_string(enum ath_chanctx_state state)
 188 {
 189         switch (state) {
 190                 case_rtn_string(ATH_CHANCTX_STATE_IDLE);
 191                 case_rtn_string(ATH_CHANCTX_STATE_WAIT_FOR_BEACON);
 192                 case_rtn_string(ATH_CHANCTX_STATE_WAIT_FOR_TIMER);
 193                 case_rtn_string(ATH_CHANCTX_STATE_SWITCH);
 194                 case_rtn_string(ATH_CHANCTX_STATE_FORCE_ACTIVE);
 195         default:
 196                 return "unknown";
 197         }
 198 }
 199
 200 void ath_chanctx_check_active(struct ath_softc *sc, struct ath_chanctx *ctx)
 201 {
 202         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 203         struct ath_vif *avp;
 204         bool active = false;
 205         u8 n_active = 0;
 206
 207         if (!ctx)
 208                 return;
 209
 210         list_for_each_entry(avp, &ctx->vifs, list) {
 211                 struct ieee80211_vif *vif = avp->vif;
 212
 213                 switch (vif->type) {
 214                 case NL80211_IFTYPE_P2P_CLIENT:
 215                 case NL80211_IFTYPE_STATION:
 216                         if (vif->bss_conf.assoc)
 217                                 active = true;
 218                         break;
 219                 default:
 220                         active = true;
 221                         break;
 222                 }
 223         }
 224         ctx->active = active;
 225
 226         ath_for_each_chanctx(sc, ctx) {
 227                 if (!ctx->assigned || list_empty(&ctx->vifs))
 228                         continue;
 229                 n_active++;
 230         }
 231
 232         if (n_active <= 1) {
 233                 clear_bit(ATH_OP_MULTI_CHANNEL, &common->op_flags);
 234                 return;
 235         }
 236         if (test_and_set_bit(ATH_OP_MULTI_CHANNEL, &common->op_flags))
 237                 return;
 238
 239         if (ath9k_is_chanctx_enabled()) {
 240                 ath_chanctx_event(sc, NULL,
 241                                   ATH_CHANCTX_EVENT_ENABLE_MULTICHANNEL);
 242         }
 243 }
 244
 245 static struct ath_chanctx *
 246 ath_chanctx_get_next(struct ath_softc *sc, struct ath_chanctx *ctx)
 247 {
 248         int idx = ctx - &sc->chanctx[0];
 249
 250         return &sc->chanctx[!idx];
 251 }
 252
 253 static void ath_chanctx_adjust_tbtt_delta(struct ath_softc *sc)
 254 {
 255         struct ath_chanctx *prev, *cur;
 256         struct timespec ts;
 257         u32 cur_tsf, prev_tsf, beacon_int;
 258         s32 offset;
 259
 260         beacon_int = TU_TO_USEC(sc->cur_chan->beacon.beacon_interval);
 261
 262         cur = sc->cur_chan;
 263         prev = ath_chanctx_get_next(sc, cur);
 264
 265         getrawmonotonic(&ts);
 266         cur_tsf = (u32) cur->tsf_val +
 267                   ath9k_hw_get_tsf_offset(&cur->tsf_ts, &ts);
 268
 269         prev_tsf = prev->last_beacon - (u32) prev->tsf_val + cur_tsf;
 270         prev_tsf -= ath9k_hw_get_tsf_offset(&prev->tsf_ts, &ts);
 271
 272         /* Adjust the TSF time of the AP chanctx to keep its beacons
 273          * at half beacon interval offset relative to the STA chanctx.
 274          */
 275         offset = cur_tsf - prev_tsf;
 276
 277         /* Ignore stale data or spurious timestamps */
 278         if (offset < 0 || offset > 3 * beacon_int)
 279                 return;
 280
 281         offset = beacon_int / 2 - (offset % beacon_int);
 282         prev->tsf_val += offset;
 283 }
 284
 285 /* Configure the TSF based hardware timer for a channel switch.
 286  * Also set up backup software timer, in case the gen timer fails.
 287  * This could be caused by a hardware reset.
 288  */
 289 static void ath_chanctx_setup_timer(struct ath_softc *sc, u32 tsf_time)
 290 {
 291         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 292         struct ath_hw *ah = sc->sc_ah;
 293
 294         ath9k_hw_gen_timer_start(ah, sc->p2p_ps_timer, tsf_time, 1000000);
 295         tsf_time -= ath9k_hw_gettsf32(ah);
 296         tsf_time = msecs_to_jiffies(tsf_time / 1000) + 1;
 297         mod_timer(&sc->sched.timer, jiffies + tsf_time);
 298
 299         ath_dbg(common, CHAN_CTX,
 300                 "Setup chanctx timer with timeout: %d ms\n", jiffies_to_msecs(tsf_time));
 301 }
 302
 303 void ath_chanctx_event(struct ath_softc *sc, struct ieee80211_vif *vif,
 304                        enum ath_chanctx_event ev)
 305 {
 306         struct ath_hw *ah = sc->sc_ah;
 307         struct ath_common *common = ath9k_hw_common(ah);
 308         struct ath_beacon_config *cur_conf;
 309         struct ath_vif *avp = NULL;
 310         struct ath_chanctx *ctx;
 311         u32 tsf_time;
 312         u32 beacon_int;
 313         bool noa_changed = false;
 314
 315         if (vif)
 316                 avp = (struct ath_vif *) vif->drv_priv;
 317
 318         spin_lock_bh(&sc->chan_lock);
 319
 320         ath_dbg(common, CHAN_CTX, "cur_chan: %d MHz, event: %s, state: %s\n",
 321                 sc->cur_chan->chandef.center_freq1,
 322                 chanctx_event_string(ev),
 323                 chanctx_state_string(sc->sched.state));
 324
 325         switch (ev) {
 326         case ATH_CHANCTX_EVENT_BEACON_PREPARE:
 327                 if (avp->offchannel_duration)
 328                         avp->offchannel_duration = 0;
 329
 330                 if (avp->chanctx != sc->cur_chan) {
 331                         ath_dbg(common, CHAN_CTX,
 332                                 "Contexts differ, not preparing beacon\n");
 333                         break;
 334                 }
 335
 336                 if (sc->sched.offchannel_pending) {
 337                         sc->sched.offchannel_pending = false;
 338                         sc->next_chan = &sc->offchannel.chan;
 339                         sc->sched.state = ATH_CHANCTX_STATE_WAIT_FOR_BEACON;
 340                         ath_dbg(common, CHAN_CTX,
 341                                 "Setting offchannel_pending to false\n");
 342                 }
 343
 344                 ctx = ath_chanctx_get_next(sc, sc->cur_chan);
 345                 if (ctx->active && sc->sched.state == ATH_CHANCTX_STATE_IDLE) {
 346                         sc->next_chan = ctx;
 347                         sc->sched.state = ATH_CHANCTX_STATE_WAIT_FOR_BEACON;
 348                         ath_dbg(common, CHAN_CTX,
 349                                 "Set next context, move chanctx state to WAIT_FOR_BEACON\n");
 350                 }
 351
 352                 /* if the timer missed its window, use the next interval */
 353                 if (sc->sched.state == ATH_CHANCTX_STATE_WAIT_FOR_TIMER) {
 354                         sc->sched.state = ATH_CHANCTX_STATE_WAIT_FOR_BEACON;
 355                         ath_dbg(common, CHAN_CTX,
 356                                 "Move chanctx state from WAIT_FOR_TIMER to WAIT_FOR_BEACON\n");
 357                 }
 358
 359                 if (sc->sched.state != ATH_CHANCTX_STATE_WAIT_FOR_BEACON)
 360                         break;
 361
 362                 ath_dbg(common, CHAN_CTX, "Preparing beacon for vif: %pM\n", vif->addr);
 363
 364                 sc->sched.beacon_pending = true;
 365                 sc->sched.next_tbtt = REG_READ(ah, AR_NEXT_TBTT_TIMER);
 366
 367                 cur_conf = &sc->cur_chan->beacon;
 368                 beacon_int = TU_TO_USEC(cur_conf->beacon_interval);
 369
 370                 /* defer channel switch by a quarter beacon interval */
 371                 tsf_time = sc->sched.next_tbtt + beacon_int / 4;
 372                 sc->sched.switch_start_time = tsf_time;
 373                 sc->cur_chan->last_beacon = sc->sched.next_tbtt;
 374
 375                 /* Prevent wrap-around issues */
 376                 if (avp->periodic_noa_duration &&
 377                     tsf_time - avp->periodic_noa_start > BIT(30))
 378                         avp->periodic_noa_duration = 0;
 379
 380                 if (ctx->active) {
 381                         avp->periodic_noa_start = tsf_time;
 382                         avp->periodic_noa_duration =
 383                                 TU_TO_USEC(cur_conf->beacon_interval) / 2 -
 384                                 sc->sched.channel_switch_time;
 385                         noa_changed = true;
 386                 } else if (!ctx->active) {
 387                         avp->periodic_noa_duration = 0;
 388                         noa_changed = true;
 389                 }
 390
 391                 /* If at least two consecutive beacons were missed on the STA
 392                  * chanctx, stay on the STA channel for one extra beacon period,
 393                  * to resync the timer properly.
 394                  */
 395                 if (ctx->active && sc->sched.beacon_miss >= 2)
 396                         sc->sched.offchannel_duration = 3 * beacon_int / 2;
 397
 398                 if (sc->sched.offchannel_duration) {
 399                         noa_changed = true;
 400                         avp->offchannel_start = tsf_time;
 401                         avp->offchannel_duration =
 402                                 sc->sched.offchannel_duration;
 403                 }
 404
 405                 if (noa_changed)
 406                         avp->noa_index++;
 407
 408                 ath_dbg(common, CHAN_CTX,
 409                         "periodic_noa_duration: %d, periodic_noa_start: %d, noa_index: %d\n",
 410                         avp->periodic_noa_duration,
 411                         avp->periodic_noa_start,
 412                         avp->noa_index);
 413
 414                 break;
 415         case ATH_CHANCTX_EVENT_BEACON_SENT:
 416                 if (!sc->sched.beacon_pending) {
 417                         ath_dbg(common, CHAN_CTX,
 418                                 "No pending beacon\n");
 419                         break;
 420                 }
 421
 422                 sc->sched.beacon_pending = false;
 423                 if (sc->sched.state != ATH_CHANCTX_STATE_WAIT_FOR_BEACON)
 424                         break;
 425
 426                 ath_dbg(common, CHAN_CTX,
 427                         "Move chanctx state to WAIT_FOR_TIMER\n");
 428
 429                 sc->sched.state = ATH_CHANCTX_STATE_WAIT_FOR_TIMER;
 430                 ath_chanctx_setup_timer(sc, sc->sched.switch_start_time);
 431                 break;
 432         case ATH_CHANCTX_EVENT_TSF_TIMER:
 433                 if (sc->sched.state != ATH_CHANCTX_STATE_WAIT_FOR_TIMER)
 434                         break;
 435
 436                 if (!sc->cur_chan->switch_after_beacon &&
 437                     sc->sched.beacon_pending)
 438                         sc->sched.beacon_miss++;
 439
 440                 ath_dbg(common, CHAN_CTX,
 441                         "Move chanctx state to SWITCH\n");
 442
 443                 sc->sched.state = ATH_CHANCTX_STATE_SWITCH;
 444                 ieee80211_queue_work(sc->hw, &sc->chanctx_work);
 445                 break;
 446         case ATH_CHANCTX_EVENT_BEACON_RECEIVED:
 447                 if (!test_bit(ATH_OP_MULTI_CHANNEL, &common->op_flags) ||
 448                     sc->cur_chan == &sc->offchannel.chan)
 449                         break;
 450
 451                 ath_chanctx_adjust_tbtt_delta(sc);
 452                 sc->sched.beacon_pending = false;
 453                 sc->sched.beacon_miss = 0;
 454
 455                 /* TSF time might have been updated by the incoming beacon,
 456                  * need update the channel switch timer to reflect the change.
 457                  */
 458                 tsf_time = sc->sched.switch_start_time;
 459                 tsf_time -= (u32) sc->cur_chan->tsf_val +
 460                         ath9k_hw_get_tsf_offset(&sc->cur_chan->tsf_ts, NULL);
 461                 tsf_time += ath9k_hw_gettsf32(ah);
 462
 463
 464                 ath_chanctx_setup_timer(sc, tsf_time);
 465                 break;
 466         case ATH_CHANCTX_EVENT_ASSOC:
 467                 if (sc->sched.state != ATH_CHANCTX_STATE_FORCE_ACTIVE ||
 468                     avp->chanctx != sc->cur_chan)
 469                         break;
 470
 471                 ath_dbg(common, CHAN_CTX,
 472                         "Move chanctx state from FORCE_ACTIVE to IDLE\n");
 473
 474                 sc->sched.state = ATH_CHANCTX_STATE_IDLE;
 475                 /* fall through */
 476         case ATH_CHANCTX_EVENT_SWITCH:
 477                 if (!test_bit(ATH_OP_MULTI_CHANNEL, &common->op_flags) ||
 478                     sc->sched.state == ATH_CHANCTX_STATE_FORCE_ACTIVE ||
 479                     sc->cur_chan->switch_after_beacon ||
 480                     sc->cur_chan == &sc->offchannel.chan)
 481                         break;
 482
 483                 /* If this is a station chanctx, stay active for a half
 484                  * beacon period (minus channel switch time)
 485                  */
 486                 sc->next_chan = ath_chanctx_get_next(sc, sc->cur_chan);
 487                 cur_conf = &sc->cur_chan->beacon;
 488
 489                 ath_dbg(common, CHAN_CTX,
 490                         "Move chanctx state to WAIT_FOR_TIMER (event SWITCH)\n");
 491
 492                 sc->sched.state = ATH_CHANCTX_STATE_WAIT_FOR_TIMER;
 493
 494                 tsf_time = TU_TO_USEC(cur_conf->beacon_interval) / 2;
 495                 if (sc->sched.beacon_miss >= 2) {
 496                         sc->sched.beacon_miss = 0;
 497                         tsf_time *= 3;
 498                 }
 499
 500                 tsf_time -= sc->sched.channel_switch_time;
 501                 tsf_time += ath9k_hw_gettsf32(sc->sc_ah);
 502                 sc->sched.switch_start_time = tsf_time;
 503
 504                 ath_chanctx_setup_timer(sc, tsf_time);
 505                 sc->sched.beacon_pending = true;
 506                 break;
 507         case ATH_CHANCTX_EVENT_ENABLE_MULTICHANNEL:
 508                 if (sc->cur_chan == &sc->offchannel.chan ||
 509                     sc->cur_chan->switch_after_beacon)
 510                         break;
 511
 512                 sc->next_chan = ath_chanctx_get_next(sc, sc->cur_chan);
 513                 ieee80211_queue_work(sc->hw, &sc->chanctx_work);
 514                 break;
 515         case ATH_CHANCTX_EVENT_UNASSIGN:
 516                 if (sc->cur_chan->assigned) {
 517                         if (sc->next_chan && !sc->next_chan->assigned &&
 518                             sc->next_chan != &sc->offchannel.chan)
 519                                 sc->sched.state = ATH_CHANCTX_STATE_IDLE;
 520                         break;
 521                 }
 522
 523                 ctx = ath_chanctx_get_next(sc, sc->cur_chan);
 524                 sc->sched.state = ATH_CHANCTX_STATE_IDLE;
 525                 if (!ctx->assigned)
 526                         break;
 527
 528                 sc->next_chan = ctx;
 529                 ieee80211_queue_work(sc->hw, &sc->chanctx_work);
 530                 break;
 531         case ATH_CHANCTX_EVENT_ASSIGN:
 532                 /*
 533                  * When adding a new channel context, check if a scan
 534                  * is in progress and abort it since the addition of
 535                  * a new channel context is usually followed by VIF
 536                  * assignment, in which case we have to start multi-channel
 537                  * operation.
 538                  */
 539                 if (test_bit(ATH_OP_SCANNING, &common->op_flags)) {
 540                         ath_dbg(common, CHAN_CTX,
 541                                 "Aborting HW scan to add new context\n");
 542
 543                         spin_unlock_bh(&sc->chan_lock);
 544                         del_timer_sync(&sc->offchannel.timer);
 545                         ath_scan_complete(sc, true);
 546                         spin_lock_bh(&sc->chan_lock);
 547                 }
 548                 break;
 549         case ATH_CHANCTX_EVENT_CHANGE:
 550                 break;
 551         }
 552
 553         spin_unlock_bh(&sc->chan_lock);
 554 }
 555
 556 void ath_chanctx_beacon_sent_ev(struct ath_softc *sc,
 557                                 enum ath_chanctx_event ev)
 558 {
 559         if (sc->sched.beacon_pending)
 560                 ath_chanctx_event(sc, NULL, ev);
 561 }
 562
 563 void ath_chanctx_beacon_recv_ev(struct ath_softc *sc, u32 ts,
 564                                 enum ath_chanctx_event ev)
 565 {
 566         sc->sched.next_tbtt = ts;
 567         ath_chanctx_event(sc, NULL, ev);
 568 }
 569
 570 static int ath_scan_channel_duration(struct ath_softc *sc,
 571                                      struct ieee80211_channel *chan)
 572 {
 573         struct cfg80211_scan_request *req = sc->offchannel.scan_req;
 574
 575         if (!req->n_ssids || (chan->flags & IEEE80211_CHAN_NO_IR))
 576                 return (HZ / 9); /* ~110 ms */
 577
 578         return (HZ / 16); /* ~60 ms */
 579 }
 580
 581 static void ath_chanctx_switch(struct ath_softc *sc, struct ath_chanctx *ctx,
 582                                struct cfg80211_chan_def *chandef)
 583 {
 584         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 585
 586         spin_lock_bh(&sc->chan_lock);
 587
 588         if (test_bit(ATH_OP_MULTI_CHANNEL, &common->op_flags) &&
 589             (sc->cur_chan != ctx) && (ctx == &sc->offchannel.chan)) {
 590                 sc->sched.offchannel_pending = true;
 591                 if (chandef)
 592                         ctx->chandef = *chandef;
 593                 spin_unlock_bh(&sc->chan_lock);
 594                 ath_dbg(common, CHAN_CTX,
 595                         "Set offchannel_pending to true\n");
 596                 return;
 597         }
 598
 599         sc->next_chan = ctx;
 600         if (chandef) {
 601                 ctx->chandef = *chandef;
 602                 ath_dbg(common, CHAN_CTX,
 603                         "Assigned next_chan to %d MHz\n", chandef->center_freq1);
 604         }
 605
 606         if (sc->next_chan == &sc->offchannel.chan) {
 607                 sc->sched.offchannel_duration =
 608                         jiffies_to_usecs(sc->offchannel.duration) +
 609                         sc->sched.channel_switch_time;
 610
 611                 if (chandef) {
 612                         ath_dbg(common, CHAN_CTX,
 613                                 "Offchannel duration for chan %d MHz : %u\n",
 614                                 chandef->center_freq1,
 615                                 sc->sched.offchannel_duration);
 616                 }
 617         }
 618         spin_unlock_bh(&sc->chan_lock);
 619         ieee80211_queue_work(sc->hw, &sc->chanctx_work);
 620 }
 621
 622 static void ath_chanctx_offchan_switch(struct ath_softc *sc,
 623                                        struct ieee80211_channel *chan)
 624 {
 625         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 626         struct cfg80211_chan_def chandef;
 627
 628         cfg80211_chandef_create(&chandef, chan, NL80211_CHAN_NO_HT);
 629         ath_dbg(common, CHAN_CTX,
 630                 "Channel definition created: %d MHz\n", chandef.center_freq1);
 631
 632         ath_chanctx_switch(sc, &sc->offchannel.chan, &chandef);
 633 }
 634
 635 static struct ath_chanctx *ath_chanctx_get_oper_chan(struct ath_softc *sc,
 636                                                      bool active)
 637 {
 638         struct ath_chanctx *ctx;
 639
 640         ath_for_each_chanctx(sc, ctx) {
 641                 if (!ctx->assigned || list_empty(&ctx->vifs))
 642                         continue;
 643                 if (active && !ctx->active)
 644                         continue;
 645
 646                 if (ctx->switch_after_beacon)
 647                         return ctx;
 648         }
 649
 650         return &sc->chanctx[0];
 651 }
 652
 653 static void
 654 ath_scan_next_channel(struct ath_softc *sc)
 655 {
 656         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 657         struct cfg80211_scan_request *req = sc->offchannel.scan_req;
 658         struct ieee80211_channel *chan;
 659
 660         if (sc->offchannel.scan_idx >= req->n_channels) {
 661                 ath_dbg(common, CHAN_CTX,
 662                         "Moving offchannel state to ATH_OFFCHANNEL_IDLE, "
 663                         "scan_idx: %d, n_channels: %d\n",
 664                         sc->offchannel.scan_idx,
 665                         req->n_channels);
 666
 667                 sc->offchannel.state = ATH_OFFCHANNEL_IDLE;
 668                 ath_chanctx_switch(sc, ath_chanctx_get_oper_chan(sc, false),
 669                                    NULL);
 670                 return;
 671         }
 672
 673         ath_dbg(common, CHAN_CTX,
 674                 "Moving offchannel state to ATH_OFFCHANNEL_PROBE_SEND, scan_idx: %d\n",
 675                 sc->offchannel.scan_idx);
 676
 677         chan = req->channels[sc->offchannel.scan_idx++];
 678         sc->offchannel.duration = ath_scan_channel_duration(sc, chan);
 679         sc->offchannel.state = ATH_OFFCHANNEL_PROBE_SEND;
 680
 681         ath_chanctx_offchan_switch(sc, chan);
 682 }
 683
 684 void ath_offchannel_next(struct ath_softc *sc)
 685 {
 686         struct ieee80211_vif *vif;
 687
 688         if (sc->offchannel.scan_req) {
 689                 vif = sc->offchannel.scan_vif;
 690                 sc->offchannel.chan.txpower = vif->bss_conf.txpower;
 691                 ath_scan_next_channel(sc);
 692         } else if (sc->offchannel.roc_vif) {
 693                 vif = sc->offchannel.roc_vif;
 694                 sc->offchannel.chan.txpower = vif->bss_conf.txpower;
 695                 sc->offchannel.duration =
 696                         msecs_to_jiffies(sc->offchannel.roc_duration);
 697                 sc->offchannel.state = ATH_OFFCHANNEL_ROC_START;
 698                 ath_chanctx_offchan_switch(sc, sc->offchannel.roc_chan);
 699         } else {
 700                 ath_chanctx_switch(sc, ath_chanctx_get_oper_chan(sc, false),
 701                                    NULL);
 702                 sc->offchannel.state = ATH_OFFCHANNEL_IDLE;
 703                 if (sc->ps_idle)
 704                         ath_cancel_work(sc);
 705         }
 706 }
 707
 708 void ath_roc_complete(struct ath_softc *sc, bool abort)
 709 {
 710         sc->offchannel.roc_vif = NULL;
 711         sc->offchannel.roc_chan = NULL;
 712         if (!abort)
 713                 ieee80211_remain_on_channel_expired(sc->hw);
 714         ath_offchannel_next(sc);
 715         ath9k_ps_restore(sc);
 716 }
 717
 718 void ath_scan_complete(struct ath_softc *sc, bool abort)
 719 {
 720         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 721
 722         if (abort)
 723                 ath_dbg(common, CHAN_CTX, "HW scan aborted\n");
 724         else
 725                 ath_dbg(common, CHAN_CTX, "HW scan complete\n");
 726
 727         sc->offchannel.scan_req = NULL;
 728         sc->offchannel.scan_vif = NULL;
 729         sc->offchannel.state = ATH_OFFCHANNEL_IDLE;
 730         ieee80211_scan_completed(sc->hw, abort);
 731         clear_bit(ATH_OP_SCANNING, &common->op_flags);
 732         ath_offchannel_next(sc);
 733         ath9k_ps_restore(sc);
 734 }
 735
 736 static void ath_scan_send_probe(struct ath_softc *sc,
 737                                 struct cfg80211_ssid *ssid)
 738 {
 739         struct cfg80211_scan_request *req = sc->offchannel.scan_req;
 740         struct ieee80211_vif *vif = sc->offchannel.scan_vif;
 741         struct ath_tx_control txctl = {};
 742         struct sk_buff *skb;
 743         struct ieee80211_tx_info *info;
 744         int band = sc->offchannel.chan.chandef.chan->band;
 745
 746         skb = ieee80211_probereq_get(sc->hw, vif,
 747                         ssid->ssid, ssid->ssid_len, req->ie_len);
 748         if (!skb)
 749                 return;
 750
 751         info = IEEE80211_SKB_CB(skb);
 752         if (req->no_cck)
 753                 info->flags |= IEEE80211_TX_CTL_NO_CCK_RATE;
 754
 755         if (req->ie_len)
 756                 memcpy(skb_put(skb, req->ie_len), req->ie, req->ie_len);
 757
 758         skb_set_queue_mapping(skb, IEEE80211_AC_VO);
 759
 760         if (!ieee80211_tx_prepare_skb(sc->hw, vif, skb, band, NULL))
 761                 goto error;
 762
 763         txctl.txq = sc->tx.txq_map[IEEE80211_AC_VO];
 764         txctl.force_channel = true;
 765         if (ath_tx_start(sc->hw, skb, &txctl))
 766                 goto error;
 767
 768         return;
 769
 770 error:
 771         ieee80211_free_txskb(sc->hw, skb);
 772 }
 773
 774 static void ath_scan_channel_start(struct ath_softc *sc)
 775 {
 776         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 777         struct cfg80211_scan_request *req = sc->offchannel.scan_req;
 778         int i;
 779
 780         if (!(sc->cur_chan->chandef.chan->flags & IEEE80211_CHAN_NO_IR) &&
 781             req->n_ssids) {
 782                 for (i = 0; i < req->n_ssids; i++)
 783                         ath_scan_send_probe(sc, &req->ssids[i]);
 784
 785         }
 786
 787         ath_dbg(common, CHAN_CTX,
 788                 "Moving offchannel state to ATH_OFFCHANNEL_PROBE_WAIT\n");
 789
 790         sc->offchannel.state = ATH_OFFCHANNEL_PROBE_WAIT;
 791         mod_timer(&sc->offchannel.timer, jiffies + sc->offchannel.duration);
 792 }
 793
 794 static void ath_chanctx_timer(unsigned long data)
 795 {
 796         struct ath_softc *sc = (struct ath_softc *) data;
 797         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 798
 799         ath_dbg(common, CHAN_CTX,
 800                 "Channel context timer invoked\n");
 801
 802         ath_chanctx_event(sc, NULL, ATH_CHANCTX_EVENT_TSF_TIMER);
 803 }
 804
 805 static void ath_offchannel_timer(unsigned long data)
 806 {
 807         struct ath_softc *sc = (struct ath_softc *)data;
 808         struct ath_chanctx *ctx;
 809         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 810
 811         ath_dbg(common, CHAN_CTX, "%s: offchannel state: %s\n",
 812                 __func__, offchannel_state_string(sc->offchannel.state));
 813
 814         switch (sc->offchannel.state) {
 815         case ATH_OFFCHANNEL_PROBE_WAIT:
 816                 if (!sc->offchannel.scan_req)
 817                         return;
 818
 819                 /* get first active channel context */
 820                 ctx = ath_chanctx_get_oper_chan(sc, true);
 821                 if (ctx->active) {
 822                         ath_dbg(common, CHAN_CTX,
 823                                 "Switch to oper/active context, "
 824                                 "move offchannel state to ATH_OFFCHANNEL_SUSPEND\n");
 825
 826                         sc->offchannel.state = ATH_OFFCHANNEL_SUSPEND;
 827                         ath_chanctx_switch(sc, ctx, NULL);
 828                         mod_timer(&sc->offchannel.timer, jiffies + HZ / 10);
 829                         break;
 830                 }
 831                 /* fall through */
 832         case ATH_OFFCHANNEL_SUSPEND:
 833                 if (!sc->offchannel.scan_req)
 834                         return;
 835
 836                 ath_scan_next_channel(sc);
 837                 break;
 838         case ATH_OFFCHANNEL_ROC_START:
 839         case ATH_OFFCHANNEL_ROC_WAIT:
 840                 ctx = ath_chanctx_get_oper_chan(sc, false);
 841                 sc->offchannel.state = ATH_OFFCHANNEL_ROC_DONE;
 842                 ath_chanctx_switch(sc, ctx, NULL);
 843                 break;
 844         default:
 845                 break;
 846         }
 847 }
 848
 849 static bool
 850 ath_chanctx_send_vif_ps_frame(struct ath_softc *sc, struct ath_vif *avp,
 851                               bool powersave)
 852 {
 853         struct ieee80211_vif *vif = avp->vif;
 854         struct ieee80211_sta *sta = NULL;
 855         struct ieee80211_hdr_3addr *nullfunc;
 856         struct ath_tx_control txctl;
 857         struct sk_buff *skb;
 858         int band = sc->cur_chan->chandef.chan->band;
 859
 860         switch (vif->type) {
 861         case NL80211_IFTYPE_STATION:
 862                 if (!vif->bss_conf.assoc)
 863                         return false;
 864
 865                 skb = ieee80211_nullfunc_get(sc->hw, vif);
 866                 if (!skb)
 867                         return false;
 868
 869                 nullfunc = (struct ieee80211_hdr_3addr *) skb->data;
 870                 if (powersave)
 871                         nullfunc->frame_control |=
 872                                 cpu_to_le16(IEEE80211_FCTL_PM);
 873
 874                 skb_set_queue_mapping(skb, IEEE80211_AC_VO);
 875                 if (!ieee80211_tx_prepare_skb(sc->hw, vif, skb, band, &sta)) {
 876                         dev_kfree_skb_any(skb);
 877                         return false;
 878                 }
 879                 break;
 880         default:
 881                 return false;
 882         }
 883
 884         memset(&txctl, 0, sizeof(txctl));
 885         txctl.txq = sc->tx.txq_map[IEEE80211_AC_VO];
 886         txctl.sta = sta;
 887         txctl.force_channel = true;
 888         if (ath_tx_start(sc->hw, skb, &txctl)) {
 889                 ieee80211_free_txskb(sc->hw, skb);
 890                 return false;
 891         }
 892
 893         return true;
 894 }
 895
 896 static bool
 897 ath_chanctx_send_ps_frame(struct ath_softc *sc, bool powersave)
 898 {
 899         struct ath_vif *avp;
 900         bool sent = false;
 901
 902         rcu_read_lock();
 903         list_for_each_entry(avp, &sc->cur_chan->vifs, list) {
 904                 if (ath_chanctx_send_vif_ps_frame(sc, avp, powersave))
 905                         sent = true;
 906         }
 907         rcu_read_unlock();
 908
 909         return sent;
 910 }
 911
 912 static bool ath_chanctx_defer_switch(struct ath_softc *sc)
 913 {
 914         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 915
 916         if (sc->cur_chan == &sc->offchannel.chan)
 917                 return false;
 918
 919         switch (sc->sched.state) {
 920         case ATH_CHANCTX_STATE_SWITCH:
 921                 return false;
 922         case ATH_CHANCTX_STATE_IDLE:
 923                 if (!sc->cur_chan->switch_after_beacon)
 924                         return false;
 925
 926                 ath_dbg(common, CHAN_CTX,
 927                         "Defer switch, set chanctx state to WAIT_FOR_BEACON\n");
 928
 929                 sc->sched.state = ATH_CHANCTX_STATE_WAIT_FOR_BEACON;
 930                 break;
 931         default:
 932                 break;
 933         }
 934
 935         return true;
 936 }
 937
 938 static void ath_offchannel_channel_change(struct ath_softc *sc)
 939 {
 940         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 941
 942         ath_dbg(common, CHAN_CTX, "%s: offchannel state: %s\n",
 943                 __func__, offchannel_state_string(sc->offchannel.state));
 944
 945         switch (sc->offchannel.state) {
 946         case ATH_OFFCHANNEL_PROBE_SEND:
 947                 if (!sc->offchannel.scan_req)
 948                         return;
 949
 950                 if (sc->cur_chan->chandef.chan !=
 951                     sc->offchannel.chan.chandef.chan)
 952                         return;
 953
 954                 ath_scan_channel_start(sc);
 955                 break;
 956         case ATH_OFFCHANNEL_IDLE:
 957                 if (!sc->offchannel.scan_req)
 958                         return;
 959
 960                 ath_scan_complete(sc, false);
 961                 break;
 962         case ATH_OFFCHANNEL_ROC_START:
 963                 if (sc->cur_chan != &sc->offchannel.chan)
 964                         break;
 965
 966                 sc->offchannel.state = ATH_OFFCHANNEL_ROC_WAIT;
 967                 mod_timer(&sc->offchannel.timer,
 968                           jiffies + sc->offchannel.duration);
 969                 ieee80211_ready_on_channel(sc->hw);
 970                 break;
 971         case ATH_OFFCHANNEL_ROC_DONE:
 972                 ath_roc_complete(sc, false);
 973                 break;
 974         default:
 975                 break;
 976         }
 977 }
 978
 979 void ath_chanctx_set_next(struct ath_softc *sc, bool force)
 980 {
 981         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 982         struct timespec ts;
 983         bool measure_time = false;
 984         bool send_ps = false;
 985
 986         spin_lock_bh(&sc->chan_lock);
 987         if (!sc->next_chan) {
 988                 spin_unlock_bh(&sc->chan_lock);
 989                 return;
 990         }
 991
 992         if (!force && ath_chanctx_defer_switch(sc)) {
 993                 spin_unlock_bh(&sc->chan_lock);
 994                 return;
 995         }
 996
 997         ath_dbg(common, CHAN_CTX,
 998                 "%s: current: %d MHz, next: %d MHz\n",
 999                 __func__,
1000                 sc->cur_chan->chandef.center_freq1,
1001                 sc->next_chan->chandef.center_freq1);
1002
1003         if (sc->cur_chan != sc->next_chan) {
1004                 ath_dbg(common, CHAN_CTX,
1005                         "Stopping current chanctx: %d\n",
1006                         sc->cur_chan->chandef.center_freq1);
1007                 sc->cur_chan->stopped = true;
1008                 spin_unlock_bh(&sc->chan_lock);
1009
1010                 if (sc->next_chan == &sc->offchannel.chan) {
1011                         getrawmonotonic(&ts);
1012                         measure_time = true;
1013                 }
1014                 __ath9k_flush(sc->hw, ~0, true);
1015
1016                 if (ath_chanctx_send_ps_frame(sc, true))
1017                         __ath9k_flush(sc->hw, BIT(IEEE80211_AC_VO), false);
1018
1019                 send_ps = true;
1020                 spin_lock_bh(&sc->chan_lock);
1021
1022                 if (sc->cur_chan != &sc->offchannel.chan) {
1023                         getrawmonotonic(&sc->cur_chan->tsf_ts);
1024                         sc->cur_chan->tsf_val = ath9k_hw_gettsf64(sc->sc_ah);
1025                 }
1026         }
1027         sc->cur_chan = sc->next_chan;
1028         sc->cur_chan->stopped = false;
1029         sc->next_chan = NULL;
1030         sc->sched.offchannel_duration = 0;
1031         if (sc->sched.state != ATH_CHANCTX_STATE_FORCE_ACTIVE)
1032                 sc->sched.state = ATH_CHANCTX_STATE_IDLE;
1033
1034         spin_unlock_bh(&sc->chan_lock);
1035
1036         if (sc->sc_ah->chip_fullsleep ||
1037             memcmp(&sc->cur_chandef, &sc->cur_chan->chandef,
1038                    sizeof(sc->cur_chandef))) {
1039                 ath_dbg(common, CHAN_CTX,
1040                         "%s: Set channel %d MHz\n",
1041                         __func__, sc->cur_chan->chandef.center_freq1);
1042                 ath_set_channel(sc);
1043                 if (measure_time)
1044                         sc->sched.channel_switch_time =
1045                                 ath9k_hw_get_tsf_offset(&ts, NULL);
1046         }
1047         if (send_ps)
1048                 ath_chanctx_send_ps_frame(sc, false);
1049
1050         ath_offchannel_channel_change(sc);
1051         ath_chanctx_event(sc, NULL, ATH_CHANCTX_EVENT_SWITCH);
1052 }
1053
1054 static void ath_chanctx_work(struct work_struct *work)
1055 {
1056         struct ath_softc *sc = container_of(work, struct ath_softc,
1057                                             chanctx_work);
1058         mutex_lock(&sc->mutex);
1059         ath_chanctx_set_next(sc, false);
1060         mutex_unlock(&sc->mutex);
1061 }
1062
1063 void ath9k_offchannel_init(struct ath_softc *sc)
1064 {
1065         struct ath_chanctx *ctx;
1066         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
1067         struct ieee80211_supported_band *sband;
1068         struct ieee80211_channel *chan;
1069         int i;
1070
1071         sband = &common->sbands[IEEE80211_BAND_2GHZ];
1072         if (!sband->n_channels)
1073                 sband = &common->sbands[IEEE80211_BAND_5GHZ];
1074
1075         chan = &sband->channels[0];
1076
1077         ctx = &sc->offchannel.chan;
1078         INIT_LIST_HEAD(&ctx->vifs);
1079         ctx->txpower = ATH_TXPOWER_MAX;
1080         cfg80211_chandef_create(&ctx->chandef, chan, NL80211_CHAN_HT20);
1081
1082         for (i = 0; i < ARRAY_SIZE(ctx->acq); i++)
1083                 INIT_LIST_HEAD(&ctx->acq[i]);
1084
1085         sc->offchannel.chan.offchannel = true;
1086 }
1087
1088 void ath9k_init_channel_context(struct ath_softc *sc)
1089 {
1090         INIT_WORK(&sc->chanctx_work, ath_chanctx_work);
1091
1092         setup_timer(&sc->offchannel.timer, ath_offchannel_timer,
1093                     (unsigned long)sc);
1094         setup_timer(&sc->sched.timer, ath_chanctx_timer,
1095                     (unsigned long)sc);
1096 }
1097
1098 void ath9k_deinit_channel_context(struct ath_softc *sc)
1099 {
1100         cancel_work_sync(&sc->chanctx_work);
1101 }
1102
1103 bool ath9k_is_chanctx_enabled(void)
1104 {
1105         return (ath9k_use_chanctx == 1);
1106 }
1107
1108 /********************/
1109 /* Queue management */
1110 /********************/
1111
1112 void ath9k_chanctx_wake_queues(struct ath_softc *sc)
1113 {
1114         struct ath_hw *ah = sc->sc_ah;
1115         int i;
1116
1117         if (sc->cur_chan == &sc->offchannel.chan) {
1118                 ieee80211_wake_queue(sc->hw,
1119                                      sc->hw->offchannel_tx_hw_queue);
1120         } else {
1121                 for (i = 0; i < IEEE80211_NUM_ACS; i++)
1122                         ieee80211_wake_queue(sc->hw,
1123                                              sc->cur_chan->hw_queue_base + i);
1124         }
1125
1126         if (ah->opmode == NL80211_IFTYPE_AP)
1127                 ieee80211_wake_queue(sc->hw, sc->hw->queues - 2);
1128 }
1129
1130 /*****************/
1131 /* P2P Powersave */
1132 /*****************/
1133
1134 static void ath9k_update_p2p_ps_timer(struct ath_softc *sc, struct ath_vif *avp)
1135 {
1136         struct ath_hw *ah = sc->sc_ah;
1137         s32 tsf, target_tsf;
1138
1139         if (!avp || !avp->noa.has_next_tsf)
1140                 return;
1141
1142         ath9k_hw_gen_timer_stop(ah, sc->p2p_ps_timer);
1143
1144         tsf = ath9k_hw_gettsf32(sc->sc_ah);
1145
1146         target_tsf = avp->noa.next_tsf;
1147         if (!avp->noa.absent)
1148                 target_tsf -= ATH_P2P_PS_STOP_TIME;
1149
1150         if (target_tsf - tsf < ATH_P2P_PS_STOP_TIME)
1151                 target_tsf = tsf + ATH_P2P_PS_STOP_TIME;
1152
1153         ath9k_hw_gen_timer_start(ah, sc->p2p_ps_timer, (u32) target_tsf, 1000000);
1154 }
1155
1156 static void ath9k_update_p2p_ps(struct ath_softc *sc, struct ieee80211_vif *vif)
1157 {
1158         struct ath_vif *avp = (void *)vif->drv_priv;
1159         u32 tsf;
1160
1161         if (!sc->p2p_ps_timer)
1162                 return;
1163
1164         if (vif->type != NL80211_IFTYPE_STATION || !vif->p2p)
1165                 return;
1166
1167         sc->p2p_ps_vif = avp;
1168         tsf = ath9k_hw_gettsf32(sc->sc_ah);
1169         ieee80211_parse_p2p_noa(&vif->bss_conf.p2p_noa_attr, &avp->noa, tsf);
1170         ath9k_update_p2p_ps_timer(sc, avp);
1171 }
1172
1173 static u8 ath9k_get_ctwin(struct ath_softc *sc, struct ath_vif *avp)
1174 {
1175         struct ath_beacon_config *cur_conf = &sc->cur_chan->beacon;
1176         u8 switch_time, ctwin;
1177
1178         /*
1179          * Channel switch in multi-channel mode is deferred
1180          * by a quarter beacon interval when handling
1181          * ATH_CHANCTX_EVENT_BEACON_PREPARE, so the P2P-GO
1182          * interface is guaranteed to be discoverable
1183          * for that duration after a TBTT.
1184          */
1185         switch_time = cur_conf->beacon_interval / 4;
1186
1187         ctwin = avp->vif->bss_conf.p2p_noa_attr.oppps_ctwindow;
1188         if (ctwin && (ctwin < switch_time))
1189                 return ctwin;
1190
1191         if (switch_time < P2P_DEFAULT_CTWIN)
1192                 return 0;
1193
1194         return P2P_DEFAULT_CTWIN;
1195 }
1196
1197 void ath9k_beacon_add_noa(struct ath_softc *sc, struct ath_vif *avp,
1198                           struct sk_buff *skb)
1199 {
1200         static const u8 noa_ie_hdr[] = {
1201                 WLAN_EID_VENDOR_SPECIFIC,       /* type */
1202                 0,                              /* length */
1203                 0x50, 0x6f, 0x9a,               /* WFA OUI */
1204                 0x09,                           /* P2P subtype */
1205                 0x0c,                           /* Notice of Absence */
1206                 0x00,                           /* LSB of little-endian len */
1207                 0x00,                           /* MSB of little-endian len */
1208         };
1209
1210         struct ieee80211_p2p_noa_attr *noa;
1211         int noa_len, noa_desc, i = 0;
1212         u8 *hdr;
1213
1214         if (!avp->offchannel_duration && !avp->periodic_noa_duration)
1215                 return;
1216
1217         noa_desc = !!avp->offchannel_duration + !!avp->periodic_noa_duration;
1218         noa_len = 2 + sizeof(struct ieee80211_p2p_noa_desc) * noa_desc;
1219
1220         hdr = skb_put(skb, sizeof(noa_ie_hdr));
1221         memcpy(hdr, noa_ie_hdr, sizeof(noa_ie_hdr));
1222         hdr[1] = sizeof(noa_ie_hdr) + noa_len - 2;
1223         hdr[7] = noa_len;
1224
1225         noa = (void *) skb_put(skb, noa_len);
1226         memset(noa, 0, noa_len);
1227
1228         noa->index = avp->noa_index;
1229         noa->oppps_ctwindow = ath9k_get_ctwin(sc, avp);
1230
1231         if (avp->periodic_noa_duration) {
1232                 u32 interval = TU_TO_USEC(sc->cur_chan->beacon.beacon_interval);
1233
1234                 noa->desc[i].count = 255;
1235                 noa->desc[i].start_time = cpu_to_le32(avp->periodic_noa_start);
1236                 noa->desc[i].duration = cpu_to_le32(avp->periodic_noa_duration);
1237                 noa->desc[i].interval = cpu_to_le32(interval);
1238                 i++;
1239         }
1240
1241         if (avp->offchannel_duration) {
1242                 noa->desc[i].count = 1;
1243                 noa->desc[i].start_time = cpu_to_le32(avp->offchannel_start);
1244                 noa->desc[i].duration = cpu_to_le32(avp->offchannel_duration);
1245         }
1246 }
1247
1248 void ath9k_p2p_ps_timer(void *priv)
1249 {
1250         struct ath_softc *sc = priv;
1251         struct ath_vif *avp = sc->p2p_ps_vif;
1252         struct ieee80211_vif *vif;
1253         struct ieee80211_sta *sta;
1254         struct ath_node *an;
1255         u32 tsf;
1256
1257         del_timer_sync(&sc->sched.timer);
1258         ath9k_hw_gen_timer_stop(sc->sc_ah, sc->p2p_ps_timer);
1259         ath_chanctx_event(sc, NULL, ATH_CHANCTX_EVENT_TSF_TIMER);
1260
1261         if (!avp || avp->chanctx != sc->cur_chan)
1262                 return;
1263
1264         tsf = ath9k_hw_gettsf32(sc->sc_ah);
1265         if (!avp->noa.absent)
1266                 tsf += ATH_P2P_PS_STOP_TIME;
1267
1268         if (!avp->noa.has_next_tsf ||
1269             avp->noa.next_tsf - tsf > BIT(31))
1270                 ieee80211_update_p2p_noa(&avp->noa, tsf);
1271
1272         ath9k_update_p2p_ps_timer(sc, avp);
1273
1274         rcu_read_lock();
1275
1276         vif = avp->vif;
1277         sta = ieee80211_find_sta(vif, vif->bss_conf.bssid);
1278         if (!sta)
1279                 goto out;
1280
1281         an = (void *) sta->drv_priv;
1282         if (an->sleeping == !!avp->noa.absent)
1283                 goto out;
1284
1285         an->sleeping = avp->noa.absent;
1286         if (an->sleeping)
1287                 ath_tx_aggr_sleep(sta, sc, an);
1288         else
1289                 ath_tx_aggr_wakeup(sc, an);
1290
1291 out:
1292         rcu_read_unlock();
1293 }
1294
1295 void ath9k_p2p_bss_info_changed(struct ath_softc *sc,
1296                                 struct ieee80211_vif *vif)
1297 {
1298         unsigned long flags;
1299
1300         spin_lock_bh(&sc->sc_pcu_lock);
1301         spin_lock_irqsave(&sc->sc_pm_lock, flags);
1302         if (!(sc->ps_flags & PS_BEACON_SYNC))
1303                 ath9k_update_p2p_ps(sc, vif);
1304         spin_unlock_irqrestore(&sc->sc_pm_lock, flags);
1305         spin_unlock_bh(&sc->sc_pcu_lock);
1306 }
1307
1308 void ath9k_p2p_beacon_sync(struct ath_softc *sc)
1309 {
1310         if (sc->p2p_ps_vif)
1311                 ath9k_update_p2p_ps(sc, sc->p2p_ps_vif->vif);
1312 }
1313
1314 void ath9k_p2p_remove_vif(struct ath_softc *sc,
1315                           struct ieee80211_vif *vif)
1316 {
1317         struct ath_vif *avp = (void *)vif->drv_priv;
1318
1319         spin_lock_bh(&sc->sc_pcu_lock);
1320         if (avp == sc->p2p_ps_vif) {
1321                 sc->p2p_ps_vif = NULL;
1322                 ath9k_update_p2p_ps_timer(sc, NULL);
1323         }
1324         spin_unlock_bh(&sc->sc_pcu_lock);
1325 }
1326
1327 int ath9k_init_p2p(struct ath_softc *sc)
1328 {
1329         sc->p2p_ps_timer = ath_gen_timer_alloc(sc->sc_ah, ath9k_p2p_ps_timer,
1330                                                NULL, sc, AR_FIRST_NDP_TIMER);
1331         if (!sc->p2p_ps_timer)
1332                 return -ENOMEM;
1333
1334         return 0;
1335 }
1336
1337 void ath9k_deinit_p2p(struct ath_softc *sc)
1338 {
1339         if (sc->p2p_ps_timer)
1340                 ath_gen_timer_free(sc->sc_ah, sc->p2p_ps_timer);
1341 }
1342
1343 #endif /* CONFIG_ATH9K_CHANNEL_CONTEXT */