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
 223         ath_dbg(common, CONFIG, "Removing interface at beacon slot: %d\n",
 224                 avp->av_bslot);
 225
 226         tasklet_disable(&sc->bcon_tasklet);
 227
 228         if (bf && bf->bf_mpdu) {
 229                 struct sk_buff *skb = bf->bf_mpdu;
 230                 dma_unmap_single(sc->dev, bf->bf_buf_addr,
 231                                  skb->len, DMA_TO_DEVICE);
 232                 dev_kfree_skb_any(skb);
 233                 bf->bf_mpdu = NULL;
 234                 bf->bf_buf_addr = 0;
 235         }
 236
 237         avp->av_bcbuf = NULL;
 238         sc->beacon.bslot[avp->av_bslot] = NULL;
 239         sc->nbcnvifs--;
 240         list_add_tail(&bf->list, &sc->beacon.bbuf);
 241
 242         tasklet_enable(&sc->bcon_tasklet);
 243 }
 244
 245 static int ath9k_beacon_choose_slot(struct ath_softc *sc)
 246 {
 247         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 248         struct ath_beacon_config *cur_conf = &sc->cur_chan->beacon;
 249         u16 intval;
 250         u32 tsftu;
 251         u64 tsf;
 252         int slot;
 253
 254         if (sc->sc_ah->opmode != NL80211_IFTYPE_AP &&
 255             sc->sc_ah->opmode != NL80211_IFTYPE_MESH_POINT) {
 256                 ath_dbg(common, BEACON, "slot 0, tsf: %llu\n",
 257                         ath9k_hw_gettsf64(sc->sc_ah));
 258                 return 0;
 259         }
 260
 261         intval = cur_conf->beacon_interval ? : ATH_DEFAULT_BINTVAL;
 262         tsf = ath9k_hw_gettsf64(sc->sc_ah);
 263         tsf += TU_TO_USEC(sc->sc_ah->config.sw_beacon_response_time);
 264         tsftu = TSF_TO_TU((tsf * ATH_BCBUF) >>32, tsf * ATH_BCBUF);
 265         slot = (tsftu % (intval * ATH_BCBUF)) / intval;
 266
 267         ath_dbg(common, BEACON, "slot: %d tsf: %llu tsftu: %u\n",
 268                 slot, tsf, tsftu / ATH_BCBUF);
 269
 270         return slot;
 271 }
 272
 273 static void ath9k_set_tsfadjust(struct ath_softc *sc, struct ieee80211_vif *vif)
 274 {
 275         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 276         struct ath_vif *avp = (void *)vif->drv_priv;
 277         struct ath_beacon_config *cur_conf = &avp->chanctx->beacon;
 278         u32 tsfadjust;
 279
 280         if (avp->av_bslot == 0)
 281                 return;
 282
 283         tsfadjust = cur_conf->beacon_interval * avp->av_bslot;
 284         tsfadjust = TU_TO_USEC(tsfadjust) / ATH_BCBUF;
 285         avp->tsf_adjust = cpu_to_le64(tsfadjust);
 286
 287         ath_dbg(common, CONFIG, "tsfadjust is: %llu for bslot: %d\n",
 288                 (unsigned long long)tsfadjust, avp->av_bslot);
 289 }
 290
 291 bool ath9k_csa_is_finished(struct ath_softc *sc, struct ieee80211_vif *vif)
 292 {
 293         if (!vif || !vif->csa_active)
 294                 return false;
 295
 296         if (!ieee80211_csa_is_complete(vif))
 297                 return false;
 298
 299         ieee80211_csa_finish(vif);
 300         return true;
 301 }
 302
 303 static void ath9k_csa_update_vif(void *data, u8 *mac, struct ieee80211_vif *vif)
 304 {
 305         struct ath_softc *sc = data;
 306         ath9k_csa_is_finished(sc, vif);
 307 }
 308
 309 void ath9k_csa_update(struct ath_softc *sc)
 310 {
 311         ieee80211_iterate_active_interfaces_atomic(sc->hw,
 312                                                    IEEE80211_IFACE_ITER_NORMAL,
 313                                                    ath9k_csa_update_vif, sc);
 314 }
 315
 316 void ath9k_beacon_tasklet(unsigned long data)
 317 {
 318         struct ath_softc *sc = (struct ath_softc *)data;
 319         struct ath_hw *ah = sc->sc_ah;
 320         struct ath_common *common = ath9k_hw_common(ah);
 321         struct ath_buf *bf = NULL;
 322         struct ieee80211_vif *vif;
 323         bool edma = !!(ah->caps.hw_caps & ATH9K_HW_CAP_EDMA);
 324         int slot;
 325
 326         if (test_bit(ATH_OP_HW_RESET, &common->op_flags)) {
 327                 ath_dbg(common, RESET,
 328                         "reset work is pending, skip beaconing now\n");
 329                 return;
 330         }
 331
 332         /*
 333          * Check if the previous beacon has gone out.  If
 334          * not don't try to post another, skip this period
 335          * and wait for the next.  Missed beacons indicate
 336          * a problem and should not occur.  If we miss too
 337          * many consecutive beacons reset the device.
 338          */
 339         if (ath9k_hw_numtxpending(ah, sc->beacon.beaconq) != 0) {
 340                 sc->beacon.bmisscnt++;
 341
 342                 ath9k_hw_check_nav(ah);
 343
 344                 /*
 345                  * If the previous beacon has not been transmitted
 346                  * and a MAC/BB hang has been identified, return
 347                  * here because a chip reset would have been
 348                  * initiated.
 349                  */
 350                 if (!ath_hw_check(sc))
 351                         return;
 352
 353                 if (sc->beacon.bmisscnt < BSTUCK_THRESH * sc->nbcnvifs) {
 354                         ath_dbg(common, BSTUCK,
 355                                 "missed %u consecutive beacons\n",
 356                                 sc->beacon.bmisscnt);
 357                         ath9k_hw_stop_dma_queue(ah, sc->beacon.beaconq);
 358                         if (sc->beacon.bmisscnt > 3)
 359                                 ath9k_hw_bstuck_nfcal(ah);
 360                 } else if (sc->beacon.bmisscnt >= BSTUCK_THRESH) {
 361                         ath_dbg(common, BSTUCK, "beacon is officially stuck\n");
 362                         sc->beacon.bmisscnt = 0;
 363                         ath9k_queue_reset(sc, RESET_TYPE_BEACON_STUCK);
 364                 }
 365
 366                 return;
 367         }
 368
 369         slot = ath9k_beacon_choose_slot(sc);
 370         vif = sc->beacon.bslot[slot];
 371
 372         /* EDMA devices check that in the tx completion function. */
 373         if (!edma) {
 374                 if (ath9k_is_chanctx_enabled()) {
 375                         ath_chanctx_beacon_sent_ev(sc,
 376                                           ATH_CHANCTX_EVENT_BEACON_SENT);
 377                 }
 378
 379                 if (ath9k_csa_is_finished(sc, vif))
 380                         return;
 381         }
 382
 383         if (!vif || !vif->bss_conf.enable_beacon)
 384                 return;
 385
 386         if (ath9k_is_chanctx_enabled()) {
 387                 ath_chanctx_event(sc, vif, ATH_CHANCTX_EVENT_BEACON_PREPARE);
 388         }
 389
 390         bf = ath9k_beacon_generate(sc->hw, vif);
 391
 392         if (sc->beacon.bmisscnt != 0) {
 393                 ath_dbg(common, BSTUCK, "resume beacon xmit after %u misses\n",
 394                         sc->beacon.bmisscnt);
 395                 sc->beacon.bmisscnt = 0;
 396         }
 397
 398         /*
 399          * Handle slot time change when a non-ERP station joins/leaves
 400          * an 11g network.  The 802.11 layer notifies us via callback,
 401          * we mark updateslot, then wait one beacon before effecting
 402          * the change.  This gives associated stations at least one
 403          * beacon interval to note the state change.
 404          *
 405          * NB: The slot time change state machine is clocked according
 406          *     to whether we are bursting or staggering beacons.  We
 407          *     recognize the request to update and record the current
 408          *     slot then don't transition until that slot is reached
 409          *     again.  If we miss a beacon for that slot then we'll be
 410          *     slow to transition but we'll be sure at least one beacon
 411          *     interval has passed.  When bursting slot is always left
 412          *     set to ATH_BCBUF so this check is a noop.
 413          */
 414         if (sc->beacon.updateslot == UPDATE) {
 415                 sc->beacon.updateslot = COMMIT;
 416                 sc->beacon.slotupdate = slot;
 417         } else if (sc->beacon.updateslot == COMMIT &&
 418                    sc->beacon.slotupdate == slot) {
 419                 ah->slottime = sc->beacon.slottime;
 420                 ath9k_hw_init_global_settings(ah);
 421                 sc->beacon.updateslot = OK;
 422         }
 423
 424         if (bf) {
 425                 ath9k_reset_beacon_status(sc);
 426
 427                 ath_dbg(common, BEACON,
 428                         "Transmitting beacon for slot: %d\n", slot);
 429
 430                 /* NB: cabq traffic should already be queued and primed */
 431                 ath9k_hw_puttxbuf(ah, sc->beacon.beaconq, bf->bf_daddr);
 432
 433                 if (!edma)
 434                         ath9k_hw_txstart(ah, sc->beacon.beaconq);
 435         }
 436 }
 437
 438 /*
 439  * Both nexttbtt and intval have to be in usecs.
 440  */
 441 static void ath9k_beacon_init(struct ath_softc *sc, u32 nexttbtt,
 442                               u32 intval, bool reset_tsf)
 443 {
 444         struct ath_hw *ah = sc->sc_ah;
 445
 446         ath9k_hw_disable_interrupts(ah);
 447         if (reset_tsf)
 448                 ath9k_hw_reset_tsf(ah);
 449         ath9k_beaconq_config(sc);
 450         ath9k_hw_beaconinit(ah, nexttbtt, intval);
 451         sc->beacon.bmisscnt = 0;
 452         ath9k_hw_set_interrupts(ah);
 453         ath9k_hw_enable_interrupts(ah);
 454 }
 455
 456 /*
 457  * For multi-bss ap support beacons are either staggered evenly over N slots or
 458  * burst together.  For the former arrange for the SWBA to be delivered for each
 459  * slot. Slots that are not occupied will generate nothing.
 460  */
 461 static void ath9k_beacon_config_ap(struct ath_softc *sc,
 462                                    struct ath_beacon_config *conf)
 463 {
 464         struct ath_hw *ah = sc->sc_ah;
 465
 466         ath9k_cmn_beacon_config_ap(ah, conf, ATH_BCBUF);
 467         ath9k_beacon_init(sc, conf->nexttbtt, conf->intval, false);
 468 }
 469
 470 static void ath9k_beacon_config_sta(struct ath_hw *ah,
 471                                     struct ath_beacon_config *conf)
 472 {
 473         struct ath9k_beacon_state bs;
 474
 475         if (ath9k_cmn_beacon_config_sta(ah, conf, &bs) == -EPERM)
 476                 return;
 477
 478         ath9k_hw_disable_interrupts(ah);
 479         ath9k_hw_set_sta_beacon_timers(ah, &bs);
 480         ah->imask |= ATH9K_INT_BMISS;
 481
 482         ath9k_hw_set_interrupts(ah);
 483         ath9k_hw_enable_interrupts(ah);
 484 }
 485
 486 static void ath9k_beacon_config_adhoc(struct ath_softc *sc,
 487                                       struct ath_beacon_config *conf)
 488 {
 489         struct ath_hw *ah = sc->sc_ah;
 490         struct ath_common *common = ath9k_hw_common(ah);
 491
 492         ath9k_reset_beacon_status(sc);
 493
 494         ath9k_cmn_beacon_config_adhoc(ah, conf);
 495
 496         ath9k_beacon_init(sc, conf->nexttbtt, conf->intval, conf->ibss_creator);
 497
 498         /*
 499          * Set the global 'beacon has been configured' flag for the
 500          * joiner case in IBSS mode.
 501          */
 502         if (!conf->ibss_creator && conf->enable_beacon)
 503                 set_bit(ATH_OP_BEACONS, &common->op_flags);
 504 }
 505
 506 static bool ath9k_allow_beacon_config(struct ath_softc *sc,
 507                                       struct ieee80211_vif *vif)
 508 {
 509         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 510         struct ath_vif *avp = (void *)vif->drv_priv;
 511
 512         if (ath9k_is_chanctx_enabled()) {
 513                 /*
 514                  * If the VIF is not present in the current channel context,
 515                  * then we can't do the usual opmode checks. Allow the
 516                  * beacon config for the VIF to be updated in this case and
 517                  * return immediately.
 518                  */
 519                 if (sc->cur_chan != avp->chanctx)
 520                         return true;
 521         }
 522
 523         if (sc->sc_ah->opmode == NL80211_IFTYPE_AP) {
 524                 if ((vif->type != NL80211_IFTYPE_AP) ||
 525                     (sc->nbcnvifs > 1)) {
 526                         ath_dbg(common, CONFIG,
 527                                 "An AP interface is already present !\n");
 528                         return false;
 529                 }
 530         }
 531
 532         if (sc->sc_ah->opmode == NL80211_IFTYPE_STATION) {
 533                 if ((vif->type == NL80211_IFTYPE_STATION) &&
 534                     test_bit(ATH_OP_BEACONS, &common->op_flags) &&
 535                     vif != sc->cur_chan->primary_sta) {
 536                         ath_dbg(common, CONFIG,
 537                                 "Beacon already configured for a station interface\n");
 538                         return false;
 539                 }
 540         }
 541
 542         return true;
 543 }
 544
 545 static void ath9k_cache_beacon_config(struct ath_softc *sc,
 546                                       struct ath_chanctx *ctx,
 547                                       struct ieee80211_bss_conf *bss_conf)
 548 {
 549         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 550         struct ath_beacon_config *cur_conf = &ctx->beacon;
 551
 552         ath_dbg(common, BEACON,
 553                 "Caching beacon data for BSS: %pM\n", bss_conf->bssid);
 554
 555         cur_conf->beacon_interval = bss_conf->beacon_int;
 556         cur_conf->dtim_period = bss_conf->dtim_period;
 557         cur_conf->dtim_count = 1;
 558         cur_conf->ibss_creator = bss_conf->ibss_creator;
 559
 560         /*
 561          * It looks like mac80211 may end up using beacon interval of zero in
 562          * some cases (at least for mesh point). Avoid getting into an
 563          * infinite loop by using a bit safer value instead. To be safe,
 564          * do sanity check on beacon interval for all operating modes.
 565          */
 566         if (cur_conf->beacon_interval == 0)
 567                 cur_conf->beacon_interval = 100;
 568
 569         cur_conf->bmiss_timeout =
 570                 ATH_DEFAULT_BMISS_LIMIT * cur_conf->beacon_interval;
 571
 572         /*
 573          * We don't parse dtim period from mac80211 during the driver
 574          * initialization as it breaks association with hidden-ssid
 575          * AP and it causes latency in roaming
 576          */
 577         if (cur_conf->dtim_period == 0)
 578                 cur_conf->dtim_period = 1;
 579
 580 }
 581
 582 void ath9k_beacon_config(struct ath_softc *sc, struct ieee80211_vif *vif,
 583                          u32 changed)
 584 {
 585         struct ieee80211_bss_conf *bss_conf = &vif->bss_conf;
 586         struct ath_hw *ah = sc->sc_ah;
 587         struct ath_common *common = ath9k_hw_common(ah);
 588         struct ath_vif *avp = (void *)vif->drv_priv;
 589         struct ath_chanctx *ctx = avp->chanctx;
 590         struct ath_beacon_config *cur_conf;
 591         unsigned long flags;
 592         bool skip_beacon = false;
 593
 594         if (!ctx)
 595                 return;
 596
 597         cur_conf = &avp->chanctx->beacon;
 598         if (vif->type == NL80211_IFTYPE_AP)
 599                 ath9k_set_tsfadjust(sc, vif);
 600
 601         if (!ath9k_allow_beacon_config(sc, vif))
 602                 return;
 603
 604         if (vif->type == NL80211_IFTYPE_STATION) {
 605                 ath9k_cache_beacon_config(sc, ctx, bss_conf);
 606                 if (ctx != sc->cur_chan)
 607                         return;
 608
 609                 ath9k_set_beacon(sc);
 610                 set_bit(ATH_OP_BEACONS, &common->op_flags);
 611                 return;
 612         }
 613
 614         /*
 615          * Take care of multiple interfaces when
 616          * enabling/disabling SWBA.
 617          */
 618         if (changed & BSS_CHANGED_BEACON_ENABLED) {
 619                 if (!bss_conf->enable_beacon &&
 620                     (sc->nbcnvifs <= 1)) {
 621                         cur_conf->enable_beacon = false;
 622                 } else if (bss_conf->enable_beacon) {
 623                         cur_conf->enable_beacon = true;
 624                         ath9k_cache_beacon_config(sc, ctx, bss_conf);
 625                 }
 626         }
 627
 628         if (ctx != sc->cur_chan)
 629                 return;
 630
 631         /*
 632          * Configure the HW beacon registers only when we have a valid
 633          * beacon interval.
 634          */
 635         if (cur_conf->beacon_interval) {
 636                 /*
 637                  * If we are joining an existing IBSS network, start beaconing
 638                  * only after a TSF-sync has taken place. Ensure that this
 639                  * happens by setting the appropriate flags.
 640                  */
 641                 if ((changed & BSS_CHANGED_IBSS) && !bss_conf->ibss_creator &&
 642                     bss_conf->enable_beacon) {
 643                         spin_lock_irqsave(&sc->sc_pm_lock, flags);
 644                         sc->ps_flags |= PS_BEACON_SYNC | PS_WAIT_FOR_BEACON;
 645                         spin_unlock_irqrestore(&sc->sc_pm_lock, flags);
 646                         skip_beacon = true;
 647                 } else {
 648                         ath9k_set_beacon(sc);
 649                 }
 650
 651                 /*
 652                  * Do not set the ATH_OP_BEACONS flag for IBSS joiner mode
 653                  * here, it is done in ath9k_beacon_config_adhoc().
 654                  */
 655                 if (cur_conf->enable_beacon && !skip_beacon)
 656                         set_bit(ATH_OP_BEACONS, &common->op_flags);
 657                 else
 658                         clear_bit(ATH_OP_BEACONS, &common->op_flags);
 659         }
 660 }
 661
 662 void ath9k_set_beacon(struct ath_softc *sc)
 663 {
 664         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 665         struct ath_beacon_config *cur_conf = &sc->cur_chan->beacon;
 666
 667         switch (sc->sc_ah->opmode) {
 668         case NL80211_IFTYPE_AP:
 669         case NL80211_IFTYPE_MESH_POINT:
 670                 ath9k_beacon_config_ap(sc, cur_conf);
 671                 break;
 672         case NL80211_IFTYPE_ADHOC:
 673                 ath9k_beacon_config_adhoc(sc, cur_conf);
 674                 break;
 675         case NL80211_IFTYPE_STATION:
 676                 ath9k_beacon_config_sta(sc->sc_ah, cur_conf);
 677                 break;
 678         default:
 679                 ath_dbg(common, CONFIG, "Unsupported beaconing mode\n");
 680                 return;
 681         }
 682 }