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

   1 /*
   2  * Copyright (c) 2008-2011 Atheros Communications Inc.
   3  *
   4  * Permission to use, copy, modify, and/or distribute this software for any
   5  * purpose with or without fee is hereby granted, provided that the above
   6  * copyright notice and this permission notice appear in all copies.
   7  *
   8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
   9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  15  */
  16
  17 #include <linux/dma-mapping.h>
  18 #include "ath9k.h"
  19
  20 #define FUDGE 2
  21
  22 static void ath9k_reset_beacon_status(struct ath_softc *sc)
  23 {
  24         sc->beacon.tx_processed = false;
  25         sc->beacon.tx_last = false;
  26 }
  27
  28 /*
  29  *  This function will modify certain transmit queue properties depending on
  30  *  the operating mode of the station (AP or AdHoc).  Parameters are AIFS
  31  *  settings and channel width min/max
  32 */
  33 static void ath9k_beaconq_config(struct ath_softc *sc)
  34 {
  35         struct ath_hw *ah = sc->sc_ah;
  36         struct ath_common *common = ath9k_hw_common(ah);
  37         struct ath9k_tx_queue_info qi, qi_be;
  38         struct ath_txq *txq;
  39
  40         ath9k_hw_get_txq_props(ah, sc->beacon.beaconq, &qi);
  41
  42         if (sc->sc_ah->opmode == NL80211_IFTYPE_AP ||
  43             sc->sc_ah->opmode == NL80211_IFTYPE_MESH_POINT) {
  44                 /* Always burst out beacon and CAB traffic. */
  45                 qi.tqi_aifs = 1;
  46                 qi.tqi_cwmin = 0;
  47                 qi.tqi_cwmax = 0;
  48         } else {
  49                 /* Adhoc mode; important thing is to use 2x cwmin. */
  50                 txq = sc->tx.txq_map[IEEE80211_AC_BE];
  51                 ath9k_hw_get_txq_props(ah, txq->axq_qnum, &qi_be);
  52                 qi.tqi_aifs = qi_be.tqi_aifs;
  53                 if (ah->slottime == ATH9K_SLOT_TIME_20)
  54                         qi.tqi_cwmin = 2*qi_be.tqi_cwmin;
  55                 else
  56                         qi.tqi_cwmin = 4*qi_be.tqi_cwmin;
  57                 qi.tqi_cwmax = qi_be.tqi_cwmax;
  58         }
  59
  60         if (!ath9k_hw_set_txq_props(ah, sc->beacon.beaconq, &qi)) {
  61                 ath_err(common, "Unable to update h/w beacon queue parameters\n");
  62         } else {
  63                 ath9k_hw_resettxqueue(ah, sc->beacon.beaconq);
  64         }
  65 }
  66
  67 /*
  68  *  Associates the beacon frame buffer with a transmit descriptor.  Will set
  69  *  up rate codes, and channel flags. Beacons are always sent out at the
  70  *  lowest rate, and are not retried.
  71 */
  72 static void ath9k_beacon_setup(struct ath_softc *sc, struct ieee80211_vif *vif,
  73                              struct ath_buf *bf, int rateidx)
  74 {
  75         struct sk_buff *skb = bf->bf_mpdu;
  76         struct ath_hw *ah = sc->sc_ah;
  77         struct ath_common *common = ath9k_hw_common(ah);
  78         struct ath_tx_info info;
  79         struct ieee80211_supported_band *sband;
  80         u8 chainmask = ah->txchainmask;
  81         u8 i, rate = 0;
  82
  83         sband = &common->sbands[sc->cur_chandef.chan->band];
  84         rate = sband->bitrates[rateidx].hw_value;
  85         if (vif->bss_conf.use_short_preamble)
  86                 rate |= sband->bitrates[rateidx].hw_value_short;
  87
  88         memset(&info, 0, sizeof(info));
  89         info.pkt_len = skb->len + FCS_LEN;
  90         info.type = ATH9K_PKT_TYPE_BEACON;
  91         for (i = 0; i < 4; i++)
  92                 info.txpower[i] = MAX_RATE_POWER;
  93         info.keyix = ATH9K_TXKEYIX_INVALID;
  94         info.keytype = ATH9K_KEY_TYPE_CLEAR;
  95         info.flags = ATH9K_TXDESC_NOACK | ATH9K_TXDESC_CLRDMASK;
  96
  97         info.buf_addr[0] = bf->bf_buf_addr;
  98         info.buf_len[0] = roundup(skb->len, 4);
  99
 100         info.is_first = true;
 101         info.is_last = true;
 102
 103         info.qcu = sc->beacon.beaconq;
 104
 105         info.rates[0].Tries = 1;
 106         info.rates[0].Rate = rate;
 107         info.rates[0].ChSel = ath_txchainmask_reduction(sc, chainmask, rate);
 108
 109         ath9k_hw_set_txdesc(ah, bf->bf_desc, &info);
 110 }
 111
 112 static struct ath_buf *ath9k_beacon_generate(struct ieee80211_hw *hw,
 113                                              struct ieee80211_vif *vif)
 114 {
 115         struct ath_softc *sc = hw->priv;
 116         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 117         struct ath_buf *bf;
 118         struct ath_vif *avp = (void *)vif->drv_priv;
 119         struct sk_buff *skb;
 120         struct ath_txq *cabq = sc->beacon.cabq;
 121         struct ieee80211_tx_info *info;
 122         struct ieee80211_mgmt *mgmt_hdr;
 123         int cabq_depth;
 124
 125         if (avp->av_bcbuf == NULL)
 126                 return NULL;
 127
 128         bf = avp->av_bcbuf;
 129         skb = bf->bf_mpdu;
 130         if (skb) {
 131                 dma_unmap_single(sc->dev, bf->bf_buf_addr,
 132                                  skb->len, DMA_TO_DEVICE);
 133                 dev_kfree_skb_any(skb);
 134                 bf->bf_buf_addr = 0;
 135                 bf->bf_mpdu = NULL;
 136         }
 137
 138         skb = ieee80211_beacon_get(hw, vif);
 139         if (skb == NULL)
 140                 return NULL;
 141
 142         bf->bf_mpdu = skb;
 143
 144         mgmt_hdr = (struct ieee80211_mgmt *)skb->data;
 145         mgmt_hdr->u.beacon.timestamp = avp->tsf_adjust;
 146
 147         info = IEEE80211_SKB_CB(skb);
 148
 149         ath_assign_seq(common, skb);
 150
 151         if (vif->p2p)
 152                 ath9k_beacon_add_noa(sc, avp, skb);
 153
 154         bf->bf_buf_addr = dma_map_single(sc->dev, skb->data,
 155                                          skb->len, DMA_TO_DEVICE);
 156         if (unlikely(dma_mapping_error(sc->dev, bf->bf_buf_addr))) {
 157                 dev_kfree_skb_any(skb);
 158                 bf->bf_mpdu = NULL;
 159                 bf->bf_buf_addr = 0;
 160                 ath_err(common, "dma_mapping_error on beaconing\n");
 161                 return NULL;
 162         }
 163
 164         skb = ieee80211_get_buffered_bc(hw, vif);
 165
 166         /*
 167          * if the CABQ traffic from previous DTIM is pending and the current
 168          *  beacon is also a DTIM.
 169          *  1) if there is only one vif let the cab traffic continue.
 170          *  2) if there are more than one vif and we are using staggered
 171          *     beacons, then drain the cabq by dropping all the frames in
 172          *     the cabq so that the current vifs cab traffic can be scheduled.
 173          */
 174         spin_lock_bh(&cabq->axq_lock);
 175         cabq_depth = cabq->axq_depth;
 176         spin_unlock_bh(&cabq->axq_lock);
 177
 178         if (skb && cabq_depth) {
 179                 if (sc->cur_chan->nvifs > 1) {
 180                         ath_dbg(common, BEACON,
 181                                 "Flushing previous cabq traffic\n");
 182                         ath_draintxq(sc, cabq);
 183                 }
 184         }
 185
 186         ath9k_beacon_setup(sc, vif, bf, info->control.rates[0].idx);
 187
 188         if (skb)
 189                 ath_tx_cabq(hw, vif, skb);
 190
 191         return bf;
 192 }
 193
 194 void ath9k_beacon_assign_slot(struct ath_softc *sc, struct ieee80211_vif *vif)
 195 {
 196         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 197         struct ath_vif *avp = (void *)vif->drv_priv;
 198         int slot;
 199
 200         avp->av_bcbuf = list_first_entry(&sc->beacon.bbuf, struct ath_buf, list);
 201         list_del(&avp->av_bcbuf->list);
 202
 203         for (slot = 0; slot < ATH_BCBUF; slot++) {
 204                 if (sc->beacon.bslot[slot] == NULL) {
 205                         avp->av_bslot = slot;
 206                         break;
 207                 }
 208         }
 209
 210         sc->beacon.bslot[avp->av_bslot] = vif;
 211         sc->nbcnvifs++;
 212
 213         ath_dbg(common, CONFIG, "Added interface at beacon slot: %d\n",
 214                 avp->av_bslot);
 215 }
 216
 217 void ath9k_beacon_remove_slot(struct ath_softc *sc, struct ieee80211_vif *vif)
 218 {
 219         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 220         struct ath_vif *avp = (void *)vif->drv_priv;
 221         struct ath_buf *bf = avp->av_bcbuf;
 222         struct ath_beacon_config *cur_conf = &sc->cur_chan->beacon;
 223
 224         ath_dbg(common, CONFIG, "Removing interface at beacon slot: %d\n",
 225                 avp->av_bslot);
 226
 227         tasklet_disable(&sc->bcon_tasklet);
 228
 229         cur_conf->enable_beacon &= ~BIT(avp->av_bslot);
 230
 231         if (bf && bf->bf_mpdu) {
 232                 struct sk_buff *skb = bf->bf_mpdu;
 233                 dma_unmap_single(sc->dev, bf->bf_buf_addr,
 234                                  skb->len, DMA_TO_DEVICE);
 235                 dev_kfree_skb_any(skb);
 236                 bf->bf_mpdu = NULL;
 237                 bf->bf_buf_addr = 0;
 238         }
 239
 240         avp->av_bcbuf = NULL;
 241         sc->beacon.bslot[avp->av_bslot] = NULL;
 242         sc->nbcnvifs--;
 243         list_add_tail(&bf->list, &sc->beacon.bbuf);
 244
 245         tasklet_enable(&sc->bcon_tasklet);
 246 }
 247
 248 static int ath9k_beacon_choose_slot(struct ath_softc *sc)
 249 {
 250         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 251         struct ath_beacon_config *cur_conf = &sc->cur_chan->beacon;
 252         u16 intval;
 253         u32 tsftu;
 254         u64 tsf;
 255         int slot;
 256
 257         if (sc->sc_ah->opmode != NL80211_IFTYPE_AP &&
 258             sc->sc_ah->opmode != NL80211_IFTYPE_MESH_POINT) {
 259                 ath_dbg(common, BEACON, "slot 0, tsf: %llu\n",
 260                         ath9k_hw_gettsf64(sc->sc_ah));
 261                 return 0;
 262         }
 263
 264         intval = cur_conf->beacon_interval ? : ATH_DEFAULT_BINTVAL;
 265         tsf = ath9k_hw_gettsf64(sc->sc_ah);
 266         tsf += TU_TO_USEC(sc->sc_ah->config.sw_beacon_response_time);
 267         tsftu = TSF_TO_TU((tsf * ATH_BCBUF) >>32, tsf * ATH_BCBUF);
 268         slot = (tsftu % (intval * ATH_BCBUF)) / intval;
 269
 270         ath_dbg(common, BEACON, "slot: %d tsf: %llu tsftu: %u\n",
 271                 slot, tsf, tsftu / ATH_BCBUF);
 272
 273         return slot;
 274 }
 275
 276 static void ath9k_set_tsfadjust(struct ath_softc *sc, struct ieee80211_vif *vif)
 277 {
 278         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 279         struct ath_vif *avp = (void *)vif->drv_priv;
 280         struct ath_beacon_config *cur_conf = &avp->chanctx->beacon;
 281         u32 tsfadjust;
 282
 283         if (avp->av_bslot == 0)
 284                 return;
 285
 286         tsfadjust = cur_conf->beacon_interval * avp->av_bslot;
 287         tsfadjust = TU_TO_USEC(tsfadjust) / ATH_BCBUF;
 288         avp->tsf_adjust = cpu_to_le64(tsfadjust);
 289
 290         ath_dbg(common, CONFIG, "tsfadjust is: %llu for bslot: %d\n",
 291                 (unsigned long long)tsfadjust, avp->av_bslot);
 292 }
 293
 294 bool ath9k_csa_is_finished(struct ath_softc *sc, struct ieee80211_vif *vif)
 295 {
 296         if (!vif || !vif->csa_active)
 297                 return false;
 298
 299         if (!ieee80211_csa_is_complete(vif))
 300                 return false;
 301
 302         ieee80211_csa_finish(vif);
 303         return true;
 304 }
 305
 306 static void ath9k_csa_update_vif(void *data, u8 *mac, struct ieee80211_vif *vif)
 307 {
 308         struct ath_softc *sc = data;
 309         ath9k_csa_is_finished(sc, vif);
 310 }
 311
 312 void ath9k_csa_update(struct ath_softc *sc)
 313 {
 314         ieee80211_iterate_active_interfaces_atomic(sc->hw,
 315                                                    IEEE80211_IFACE_ITER_NORMAL,
 316                                                    ath9k_csa_update_vif, sc);
 317 }
 318
 319 void ath9k_beacon_tasklet(unsigned long data)
 320 {
 321         struct ath_softc *sc = (struct ath_softc *)data;
 322         struct ath_hw *ah = sc->sc_ah;
 323         struct ath_common *common = ath9k_hw_common(ah);
 324         struct ath_buf *bf = NULL;
 325         struct ieee80211_vif *vif;
 326         bool edma = !!(ah->caps.hw_caps & ATH9K_HW_CAP_EDMA);
 327         int slot;
 328
 329         if (test_bit(ATH_OP_HW_RESET, &common->op_flags)) {
 330                 ath_dbg(common, RESET,
 331                         "reset work is pending, skip beaconing now\n");
 332                 return;
 333         }
 334
 335         /*
 336          * Check if the previous beacon has gone out.  If
 337          * not don't try to post another, skip this period
 338          * and wait for the next.  Missed beacons indicate
 339          * a problem and should not occur.  If we miss too
 340          * many consecutive beacons reset the device.
 341          */
 342         if (ath9k_hw_numtxpending(ah, sc->beacon.beaconq) != 0) {
 343                 sc->beacon.bmisscnt++;
 344
 345                 ath9k_hw_check_nav(ah);
 346
 347                 /*
 348                  * If the previous beacon has not been transmitted
 349                  * and a MAC/BB hang has been identified, return
 350                  * here because a chip reset would have been
 351                  * initiated.
 352                  */
 353                 if (!ath_hw_check(sc))
 354                         return;
 355
 356                 if (sc->beacon.bmisscnt < BSTUCK_THRESH * sc->nbcnvifs) {
 357                         ath_dbg(common, BSTUCK,
 358                                 "missed %u consecutive beacons\n",
 359                                 sc->beacon.bmisscnt);
 360                         ath9k_hw_stop_dma_queue(ah, sc->beacon.beaconq);
 361                         if (sc->beacon.bmisscnt > 3)
 362                                 ath9k_hw_bstuck_nfcal(ah);
 363                 } else if (sc->beacon.bmisscnt >= BSTUCK_THRESH) {
 364                         ath_dbg(common, BSTUCK, "beacon is officially stuck\n");
 365                         sc->beacon.bmisscnt = 0;
 366                         ath9k_queue_reset(sc, RESET_TYPE_BEACON_STUCK);
 367                 }
 368
 369                 return;
 370         }
 371
 372         slot = ath9k_beacon_choose_slot(sc);
 373         vif = sc->beacon.bslot[slot];
 374
 375         /* EDMA devices check that in the tx completion function. */
 376         if (!edma) {
 377                 if (ath9k_is_chanctx_enabled()) {
 378                         ath_chanctx_beacon_sent_ev(sc,
 379                                           ATH_CHANCTX_EVENT_BEACON_SENT);
 380                 }
 381
 382                 if (ath9k_csa_is_finished(sc, vif))
 383                         return;
 384         }
 385
 386         if (!vif || !vif->bss_conf.enable_beacon)
 387                 return;
 388
 389         if (ath9k_is_chanctx_enabled()) {
 390                 ath_chanctx_event(sc, vif, ATH_CHANCTX_EVENT_BEACON_PREPARE);
 391         }
 392
 393         bf = ath9k_beacon_generate(sc->hw, vif);
 394
 395         if (sc->beacon.bmisscnt != 0) {
 396                 ath_dbg(common, BSTUCK, "resume beacon xmit after %u misses\n",
 397                         sc->beacon.bmisscnt);
 398                 sc->beacon.bmisscnt = 0;
 399         }
 400
 401         /*
 402          * Handle slot time change when a non-ERP station joins/leaves
 403          * an 11g network.  The 802.11 layer notifies us via callback,
 404          * we mark updateslot, then wait one beacon before effecting
 405          * the change.  This gives associated stations at least one
 406          * beacon interval to note the state change.
 407          *
 408          * NB: The slot time change state machine is clocked according
 409          *     to whether we are bursting or staggering beacons.  We
 410          *     recognize the request to update and record the current
 411          *     slot then don't transition until that slot is reached
 412          *     again.  If we miss a beacon for that slot then we'll be
 413          *     slow to transition but we'll be sure at least one beacon
 414          *     interval has passed.  When bursting slot is always left
 415          *     set to ATH_BCBUF so this check is a noop.
 416          */
 417         if (sc->beacon.updateslot == UPDATE) {
 418                 sc->beacon.updateslot = COMMIT;
 419                 sc->beacon.slotupdate = slot;
 420         } else if (sc->beacon.updateslot == COMMIT &&
 421                    sc->beacon.slotupdate == slot) {
 422                 ah->slottime = sc->beacon.slottime;
 423                 ath9k_hw_init_global_settings(ah);
 424                 sc->beacon.updateslot = OK;
 425         }
 426
 427         if (bf) {
 428                 ath9k_reset_beacon_status(sc);
 429
 430                 ath_dbg(common, BEACON,
 431                         "Transmitting beacon for slot: %d\n", slot);
 432
 433                 /* NB: cabq traffic should already be queued and primed */
 434                 ath9k_hw_puttxbuf(ah, sc->beacon.beaconq, bf->bf_daddr);
 435
 436                 if (!edma)
 437                         ath9k_hw_txstart(ah, sc->beacon.beaconq);
 438         }
 439 }
 440
 441 /*
 442  * Both nexttbtt and intval have to be in usecs.
 443  */
 444 static void ath9k_beacon_init(struct ath_softc *sc, u32 nexttbtt,
 445                               u32 intval, bool reset_tsf)
 446 {
 447         struct ath_hw *ah = sc->sc_ah;
 448
 449         ath9k_hw_disable_interrupts(ah);
 450         if (reset_tsf)
 451                 ath9k_hw_reset_tsf(ah);
 452         ath9k_beaconq_config(sc);
 453         ath9k_hw_beaconinit(ah, nexttbtt, intval);
 454         sc->beacon.bmisscnt = 0;
 455         ath9k_hw_set_interrupts(ah);
 456         ath9k_hw_enable_interrupts(ah);
 457 }
 458
 459 /*
 460  * For multi-bss ap support beacons are either staggered evenly over N slots or
 461  * burst together.  For the former arrange for the SWBA to be delivered for each
 462  * slot. Slots that are not occupied will generate nothing.
 463  */
 464 static void ath9k_beacon_config_ap(struct ath_softc *sc,
 465                                    struct ath_beacon_config *conf)
 466 {
 467         struct ath_hw *ah = sc->sc_ah;
 468
 469         ath9k_cmn_beacon_config_ap(ah, conf, ATH_BCBUF);
 470         ath9k_beacon_init(sc, conf->nexttbtt, conf->intval, false);
 471 }
 472
 473 static void ath9k_beacon_config_sta(struct ath_hw *ah,
 474                                     struct ath_beacon_config *conf)
 475 {
 476         struct ath9k_beacon_state bs;
 477
 478         if (ath9k_cmn_beacon_config_sta(ah, conf, &bs) == -EPERM)
 479                 return;
 480
 481         ath9k_hw_disable_interrupts(ah);
 482         ath9k_hw_set_sta_beacon_timers(ah, &bs);
 483         ah->imask |= ATH9K_INT_BMISS;
 484
 485         ath9k_hw_set_interrupts(ah);
 486         ath9k_hw_enable_interrupts(ah);
 487 }
 488
 489 static void ath9k_beacon_config_adhoc(struct ath_softc *sc,
 490                                       struct ath_beacon_config *conf)
 491 {
 492         struct ath_hw *ah = sc->sc_ah;
 493         struct ath_common *common = ath9k_hw_common(ah);
 494
 495         ath9k_reset_beacon_status(sc);
 496
 497         ath9k_cmn_beacon_config_adhoc(ah, conf);
 498
 499         ath9k_beacon_init(sc, conf->nexttbtt, conf->intval, conf->ibss_creator);
 500
 501         /*
 502          * Set the global 'beacon has been configured' flag for the
 503          * joiner case in IBSS mode.
 504          */
 505         if (!conf->ibss_creator && conf->enable_beacon)
 506                 set_bit(ATH_OP_BEACONS, &common->op_flags);
 507 }
 508
 509 static bool ath9k_allow_beacon_config(struct ath_softc *sc,
 510                                       struct ieee80211_vif *vif)
 511 {
 512         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 513         struct ath_vif *avp = (void *)vif->drv_priv;
 514
 515         if (ath9k_is_chanctx_enabled()) {
 516                 /*
 517                  * If the VIF is not present in the current channel context,
 518                  * then we can't do the usual opmode checks. Allow the
 519                  * beacon config for the VIF to be updated in this case and
 520                  * return immediately.
 521                  */
 522                 if (sc->cur_chan != avp->chanctx)
 523                         return true;
 524         }
 525
 526         if (sc->sc_ah->opmode == NL80211_IFTYPE_AP) {
 527                 if (vif->type != NL80211_IFTYPE_AP) {
 528                         ath_dbg(common, CONFIG,
 529                                 "An AP interface is already present !\n");
 530                         return false;
 531                 }
 532         }
 533
 534         if (sc->sc_ah->opmode == NL80211_IFTYPE_STATION) {
 535                 if ((vif->type == NL80211_IFTYPE_STATION) &&
 536                     test_bit(ATH_OP_BEACONS, &common->op_flags) &&
 537                     vif != sc->cur_chan->primary_sta) {
 538                         ath_dbg(common, CONFIG,
 539                                 "Beacon already configured for a station interface\n");
 540                         return false;
 541                 }
 542         }
 543
 544         return true;
 545 }
 546
 547 static void ath9k_cache_beacon_config(struct ath_softc *sc,
 548                                       struct ath_chanctx *ctx,
 549                                       struct ieee80211_bss_conf *bss_conf)
 550 {
 551         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 552         struct ath_beacon_config *cur_conf = &ctx->beacon;
 553
 554         ath_dbg(common, BEACON,
 555                 "Caching beacon data for BSS: %pM\n", bss_conf->bssid);
 556
 557         cur_conf->beacon_interval = bss_conf->beacon_int;
 558         cur_conf->dtim_period = bss_conf->dtim_period;
 559         cur_conf->dtim_count = 1;
 560         cur_conf->ibss_creator = bss_conf->ibss_creator;
 561
 562         /*
 563          * It looks like mac80211 may end up using beacon interval of zero in
 564          * some cases (at least for mesh point). Avoid getting into an
 565          * infinite loop by using a bit safer value instead. To be safe,
 566          * do sanity check on beacon interval for all operating modes.
 567          */
 568         if (cur_conf->beacon_interval == 0)
 569                 cur_conf->beacon_interval = 100;
 570
 571         cur_conf->bmiss_timeout =
 572                 ATH_DEFAULT_BMISS_LIMIT * cur_conf->beacon_interval;
 573
 574         /*
 575          * We don't parse dtim period from mac80211 during the driver
 576          * initialization as it breaks association with hidden-ssid
 577          * AP and it causes latency in roaming
 578          */
 579         if (cur_conf->dtim_period == 0)
 580                 cur_conf->dtim_period = 1;
 581
 582 }
 583
 584 void ath9k_beacon_config(struct ath_softc *sc, struct ieee80211_vif *vif,
 585                          u32 changed)
 586 {
 587         struct ieee80211_bss_conf *bss_conf = &vif->bss_conf;
 588         struct ath_hw *ah = sc->sc_ah;
 589         struct ath_common *common = ath9k_hw_common(ah);
 590         struct ath_vif *avp = (void *)vif->drv_priv;
 591         struct ath_chanctx *ctx = avp->chanctx;
 592         struct ath_beacon_config *cur_conf;
 593         unsigned long flags;
 594         bool skip_beacon = false;
 595
 596         if (!ctx)
 597                 return;
 598
 599         cur_conf = &avp->chanctx->beacon;
 600         if (vif->type == NL80211_IFTYPE_AP)
 601                 ath9k_set_tsfadjust(sc, vif);
 602
 603         if (!ath9k_allow_beacon_config(sc, vif))
 604                 return;
 605
 606         if (vif->type == NL80211_IFTYPE_STATION) {
 607                 ath9k_cache_beacon_config(sc, ctx, bss_conf);
 608                 if (ctx != sc->cur_chan)
 609                         return;
 610
 611                 ath9k_set_beacon(sc);
 612                 set_bit(ATH_OP_BEACONS, &common->op_flags);
 613                 return;
 614         }
 615
 616         /*
 617          * Take care of multiple interfaces when
 618          * enabling/disabling SWBA.
 619          */
 620         if (changed & BSS_CHANGED_BEACON_ENABLED) {
 621                 bool enabled = cur_conf->enable_beacon;
 622
 623                 if (!bss_conf->enable_beacon) {
 624                         cur_conf->enable_beacon &= ~BIT(avp->av_bslot);
 625                 } else {
 626                         cur_conf->enable_beacon |= BIT(avp->av_bslot);
 627                         if (!enabled)
 628                                 ath9k_cache_beacon_config(sc, ctx, bss_conf);
 629                 }
 630         }
 631
 632         if (ctx != sc->cur_chan)
 633                 return;
 634
 635         /*
 636          * Configure the HW beacon registers only when we have a valid
 637          * beacon interval.
 638          */
 639         if (cur_conf->beacon_interval) {
 640                 /*
 641                  * If we are joining an existing IBSS network, start beaconing
 642                  * only after a TSF-sync has taken place. Ensure that this
 643                  * happens by setting the appropriate flags.
 644                  */
 645                 if ((changed & BSS_CHANGED_IBSS) && !bss_conf->ibss_creator &&
 646                     bss_conf->enable_beacon) {
 647                         spin_lock_irqsave(&sc->sc_pm_lock, flags);
 648                         sc->ps_flags |= PS_BEACON_SYNC | PS_WAIT_FOR_BEACON;
 649                         spin_unlock_irqrestore(&sc->sc_pm_lock, flags);
 650                         skip_beacon = true;
 651                 } else {
 652                         ath9k_set_beacon(sc);
 653                 }
 654
 655                 /*
 656                  * Do not set the ATH_OP_BEACONS flag for IBSS joiner mode
 657                  * here, it is done in ath9k_beacon_config_adhoc().
 658                  */
 659                 if (cur_conf->enable_beacon && !skip_beacon)
 660                         set_bit(ATH_OP_BEACONS, &common->op_flags);
 661                 else
 662                         clear_bit(ATH_OP_BEACONS, &common->op_flags);
 663         }
 664 }
 665
 666 void ath9k_set_beacon(struct ath_softc *sc)
 667 {
 668         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 669         struct ath_beacon_config *cur_conf = &sc->cur_chan->beacon;
 670
 671         switch (sc->sc_ah->opmode) {
 672         case NL80211_IFTYPE_AP:
 673         case NL80211_IFTYPE_MESH_POINT:
 674                 ath9k_beacon_config_ap(sc, cur_conf);
 675                 break;
 676         case NL80211_IFTYPE_ADHOC:
 677                 ath9k_beacon_config_adhoc(sc, cur_conf);
 678                 break;
 679         case NL80211_IFTYPE_STATION:
 680                 ath9k_beacon_config_sta(sc->sc_ah, cur_conf);
 681                 break;
 682         default:
 683                 ath_dbg(common, CONFIG, "Unsupported beaconing mode\n");
 684                 return;
 685         }
 686 }