drivers/net/wireless/ath/ath9k/recv.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 #include "ar9003_mac.h"
  20
  21 #define SKB_CB_ATHBUF(__skb)    (*((struct ath_buf **)__skb->cb))
  22
  23 static inline bool ath_is_alt_ant_ratio_better(int alt_ratio, int maxdelta,
  24                                                int mindelta, int main_rssi_avg,
  25                                                int alt_rssi_avg, int pkt_count)
  26 {
  27         return (((alt_ratio >= ATH_ANT_DIV_COMB_ALT_ANT_RATIO2) &&
  28                 (alt_rssi_avg > main_rssi_avg + maxdelta)) ||
  29                 (alt_rssi_avg > main_rssi_avg + mindelta)) && (pkt_count > 50);
  30 }
  31
  32 static inline bool ath_ant_div_comb_alt_check(u8 div_group, int alt_ratio,
  33                                         int curr_main_set, int curr_alt_set,
  34                                         int alt_rssi_avg, int main_rssi_avg)
  35 {
  36         bool result = false;
  37         switch (div_group) {
  38         case 0:
  39                 if (alt_ratio > ATH_ANT_DIV_COMB_ALT_ANT_RATIO)
  40                         result = true;
  41                 break;
  42         case 1:
  43         case 2:
  44                 if ((((curr_main_set == ATH_ANT_DIV_COMB_LNA2) &&
  45                         (curr_alt_set == ATH_ANT_DIV_COMB_LNA1) &&
  46                                 (alt_rssi_avg >= (main_rssi_avg - 5))) ||
  47                         ((curr_main_set == ATH_ANT_DIV_COMB_LNA1) &&
  48                         (curr_alt_set == ATH_ANT_DIV_COMB_LNA2) &&
  49                                 (alt_rssi_avg >= (main_rssi_avg - 2)))) &&
  50                                                         (alt_rssi_avg >= 4))
  51                         result = true;
  52                 else
  53                         result = false;
  54                 break;
  55         }
  56
  57         return result;
  58 }
  59
  60 static inline bool ath9k_check_auto_sleep(struct ath_softc *sc)
  61 {
  62         return sc->ps_enabled &&
  63                (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_AUTOSLEEP);
  64 }
  65
  66 /*
  67  * Setup and link descriptors.
  68  *
  69  * 11N: we can no longer afford to self link the last descriptor.
  70  * MAC acknowledges BA status as long as it copies frames to host
  71  * buffer (or rx fifo). This can incorrectly acknowledge packets
  72  * to a sender if last desc is self-linked.
  73  */
  74 static void ath_rx_buf_link(struct ath_softc *sc, struct ath_buf *bf)
  75 {
  76         struct ath_hw *ah = sc->sc_ah;
  77         struct ath_common *common = ath9k_hw_common(ah);
  78         struct ath_desc *ds;
  79         struct sk_buff *skb;
  80
  81         ATH_RXBUF_RESET(bf);
  82
  83         ds = bf->bf_desc;
  84         ds->ds_link = 0; /* link to null */
  85         ds->ds_data = bf->bf_buf_addr;
  86
  87         /* virtual addr of the beginning of the buffer. */
  88         skb = bf->bf_mpdu;
  89         BUG_ON(skb == NULL);
  90         ds->ds_vdata = skb->data;
  91
  92         /*
  93          * setup rx descriptors. The rx_bufsize here tells the hardware
  94          * how much data it can DMA to us and that we are prepared
  95          * to process
  96          */
  97         ath9k_hw_setuprxdesc(ah, ds,
  98                              common->rx_bufsize,
  99                              0);
 100
 101         if (sc->rx.rxlink == NULL)
 102                 ath9k_hw_putrxbuf(ah, bf->bf_daddr);
 103         else
 104                 *sc->rx.rxlink = bf->bf_daddr;
 105
 106         sc->rx.rxlink = &ds->ds_link;
 107 }
 108
 109 static void ath_setdefantenna(struct ath_softc *sc, u32 antenna)
 110 {
 111         /* XXX block beacon interrupts */
 112         ath9k_hw_setantenna(sc->sc_ah, antenna);
 113         sc->rx.defant = antenna;
 114         sc->rx.rxotherant = 0;
 115 }
 116
 117 static void ath_opmode_init(struct ath_softc *sc)
 118 {
 119         struct ath_hw *ah = sc->sc_ah;
 120         struct ath_common *common = ath9k_hw_common(ah);
 121
 122         u32 rfilt, mfilt[2];
 123
 124         /* configure rx filter */
 125         rfilt = ath_calcrxfilter(sc);
 126         ath9k_hw_setrxfilter(ah, rfilt);
 127
 128         /* configure bssid mask */
 129         ath_hw_setbssidmask(common);
 130
 131         /* configure operational mode */
 132         ath9k_hw_setopmode(ah);
 133
 134         /* calculate and install multicast filter */
 135         mfilt[0] = mfilt[1] = ~0;
 136         ath9k_hw_setmcastfilter(ah, mfilt[0], mfilt[1]);
 137 }
 138
 139 static bool ath_rx_edma_buf_link(struct ath_softc *sc,
 140                                  enum ath9k_rx_qtype qtype)
 141 {
 142         struct ath_hw *ah = sc->sc_ah;
 143         struct ath_rx_edma *rx_edma;
 144         struct sk_buff *skb;
 145         struct ath_buf *bf;
 146
 147         rx_edma = &sc->rx.rx_edma[qtype];
 148         if (skb_queue_len(&rx_edma->rx_fifo) >= rx_edma->rx_fifo_hwsize)
 149                 return false;
 150
 151         bf = list_first_entry(&sc->rx.rxbuf, struct ath_buf, list);
 152         list_del_init(&bf->list);
 153
 154         skb = bf->bf_mpdu;
 155
 156         ATH_RXBUF_RESET(bf);
 157         memset(skb->data, 0, ah->caps.rx_status_len);
 158         dma_sync_single_for_device(sc->dev, bf->bf_buf_addr,
 159                                 ah->caps.rx_status_len, DMA_TO_DEVICE);
 160
 161         SKB_CB_ATHBUF(skb) = bf;
 162         ath9k_hw_addrxbuf_edma(ah, bf->bf_buf_addr, qtype);
 163         skb_queue_tail(&rx_edma->rx_fifo, skb);
 164
 165         return true;
 166 }
 167
 168 static void ath_rx_addbuffer_edma(struct ath_softc *sc,
 169                                   enum ath9k_rx_qtype qtype, int size)
 170 {
 171         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 172         u32 nbuf = 0;
 173
 174         if (list_empty(&sc->rx.rxbuf)) {
 175                 ath_dbg(common, ATH_DBG_QUEUE, "No free rx buf available\n");
 176                 return;
 177         }
 178
 179         while (!list_empty(&sc->rx.rxbuf)) {
 180                 nbuf++;
 181
 182                 if (!ath_rx_edma_buf_link(sc, qtype))
 183                         break;
 184
 185                 if (nbuf >= size)
 186                         break;
 187         }
 188 }
 189
 190 static void ath_rx_remove_buffer(struct ath_softc *sc,
 191                                  enum ath9k_rx_qtype qtype)
 192 {
 193         struct ath_buf *bf;
 194         struct ath_rx_edma *rx_edma;
 195         struct sk_buff *skb;
 196
 197         rx_edma = &sc->rx.rx_edma[qtype];
 198
 199         while ((skb = skb_dequeue(&rx_edma->rx_fifo)) != NULL) {
 200                 bf = SKB_CB_ATHBUF(skb);
 201                 BUG_ON(!bf);
 202                 list_add_tail(&bf->list, &sc->rx.rxbuf);
 203         }
 204 }
 205
 206 static void ath_rx_edma_cleanup(struct ath_softc *sc)
 207 {
 208         struct ath_buf *bf;
 209
 210         ath_rx_remove_buffer(sc, ATH9K_RX_QUEUE_LP);
 211         ath_rx_remove_buffer(sc, ATH9K_RX_QUEUE_HP);
 212
 213         list_for_each_entry(bf, &sc->rx.rxbuf, list) {
 214                 if (bf->bf_mpdu)
 215                         dev_kfree_skb_any(bf->bf_mpdu);
 216         }
 217
 218         INIT_LIST_HEAD(&sc->rx.rxbuf);
 219
 220         kfree(sc->rx.rx_bufptr);
 221         sc->rx.rx_bufptr = NULL;
 222 }
 223
 224 static void ath_rx_edma_init_queue(struct ath_rx_edma *rx_edma, int size)
 225 {
 226         skb_queue_head_init(&rx_edma->rx_fifo);
 227         skb_queue_head_init(&rx_edma->rx_buffers);
 228         rx_edma->rx_fifo_hwsize = size;
 229 }
 230
 231 static int ath_rx_edma_init(struct ath_softc *sc, int nbufs)
 232 {
 233         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 234         struct ath_hw *ah = sc->sc_ah;
 235         struct sk_buff *skb;
 236         struct ath_buf *bf;
 237         int error = 0, i;
 238         u32 size;
 239
 240         ath9k_hw_set_rx_bufsize(ah, common->rx_bufsize -
 241                                     ah->caps.rx_status_len);
 242
 243         ath_rx_edma_init_queue(&sc->rx.rx_edma[ATH9K_RX_QUEUE_LP],
 244                                ah->caps.rx_lp_qdepth);
 245         ath_rx_edma_init_queue(&sc->rx.rx_edma[ATH9K_RX_QUEUE_HP],
 246                                ah->caps.rx_hp_qdepth);
 247
 248         size = sizeof(struct ath_buf) * nbufs;
 249         bf = kzalloc(size, GFP_KERNEL);
 250         if (!bf)
 251                 return -ENOMEM;
 252
 253         INIT_LIST_HEAD(&sc->rx.rxbuf);
 254         sc->rx.rx_bufptr = bf;
 255
 256         for (i = 0; i < nbufs; i++, bf++) {
 257                 skb = ath_rxbuf_alloc(common, common->rx_bufsize, GFP_KERNEL);
 258                 if (!skb) {
 259                         error = -ENOMEM;
 260                         goto rx_init_fail;
 261                 }
 262
 263                 memset(skb->data, 0, common->rx_bufsize);
 264                 bf->bf_mpdu = skb;
 265
 266                 bf->bf_buf_addr = dma_map_single(sc->dev, skb->data,
 267                                                  common->rx_bufsize,
 268                                                  DMA_BIDIRECTIONAL);
 269                 if (unlikely(dma_mapping_error(sc->dev,
 270                                                 bf->bf_buf_addr))) {
 271                                 dev_kfree_skb_any(skb);
 272                                 bf->bf_mpdu = NULL;
 273                                 bf->bf_buf_addr = 0;
 274                                 ath_err(common,
 275                                         "dma_mapping_error() on RX init\n");
 276                                 error = -ENOMEM;
 277                                 goto rx_init_fail;
 278                 }
 279
 280                 list_add_tail(&bf->list, &sc->rx.rxbuf);
 281         }
 282
 283         return 0;
 284
 285 rx_init_fail:
 286         ath_rx_edma_cleanup(sc);
 287         return error;
 288 }
 289
 290 static void ath_edma_start_recv(struct ath_softc *sc)
 291 {
 292         spin_lock_bh(&sc->rx.rxbuflock);
 293
 294         ath9k_hw_rxena(sc->sc_ah);
 295
 296         ath_rx_addbuffer_edma(sc, ATH9K_RX_QUEUE_HP,
 297                               sc->rx.rx_edma[ATH9K_RX_QUEUE_HP].rx_fifo_hwsize);
 298
 299         ath_rx_addbuffer_edma(sc, ATH9K_RX_QUEUE_LP,
 300                               sc->rx.rx_edma[ATH9K_RX_QUEUE_LP].rx_fifo_hwsize);
 301
 302         ath_opmode_init(sc);
 303
 304         ath9k_hw_startpcureceive(sc->sc_ah, (sc->sc_flags & SC_OP_OFFCHANNEL));
 305
 306         spin_unlock_bh(&sc->rx.rxbuflock);
 307 }
 308
 309 static void ath_edma_stop_recv(struct ath_softc *sc)
 310 {
 311         ath_rx_remove_buffer(sc, ATH9K_RX_QUEUE_HP);
 312         ath_rx_remove_buffer(sc, ATH9K_RX_QUEUE_LP);
 313 }
 314
 315 int ath_rx_init(struct ath_softc *sc, int nbufs)
 316 {
 317         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 318         struct sk_buff *skb;
 319         struct ath_buf *bf;
 320         int error = 0;
 321
 322         spin_lock_init(&sc->sc_pcu_lock);
 323         sc->sc_flags &= ~SC_OP_RXFLUSH;
 324         spin_lock_init(&sc->rx.rxbuflock);
 325
 326         common->rx_bufsize = IEEE80211_MAX_MPDU_LEN / 2 +
 327                              sc->sc_ah->caps.rx_status_len;
 328
 329         if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) {
 330                 return ath_rx_edma_init(sc, nbufs);
 331         } else {
 332                 ath_dbg(common, ATH_DBG_CONFIG, "cachelsz %u rxbufsize %u\n",
 333                         common->cachelsz, common->rx_bufsize);
 334
 335                 /* Initialize rx descriptors */
 336
 337                 error = ath_descdma_setup(sc, &sc->rx.rxdma, &sc->rx.rxbuf,
 338                                 "rx", nbufs, 1, 0);
 339                 if (error != 0) {
 340                         ath_err(common,
 341                                 "failed to allocate rx descriptors: %d\n",
 342                                 error);
 343                         goto err;
 344                 }
 345
 346                 list_for_each_entry(bf, &sc->rx.rxbuf, list) {
 347                         skb = ath_rxbuf_alloc(common, common->rx_bufsize,
 348                                               GFP_KERNEL);
 349                         if (skb == NULL) {
 350                                 error = -ENOMEM;
 351                                 goto err;
 352                         }
 353
 354                         bf->bf_mpdu = skb;
 355                         bf->bf_buf_addr = dma_map_single(sc->dev, skb->data,
 356                                         common->rx_bufsize,
 357                                         DMA_FROM_DEVICE);
 358                         if (unlikely(dma_mapping_error(sc->dev,
 359                                                         bf->bf_buf_addr))) {
 360                                 dev_kfree_skb_any(skb);
 361                                 bf->bf_mpdu = NULL;
 362                                 bf->bf_buf_addr = 0;
 363                                 ath_err(common,
 364                                         "dma_mapping_error() on RX init\n");
 365                                 error = -ENOMEM;
 366                                 goto err;
 367                         }
 368                 }
 369                 sc->rx.rxlink = NULL;
 370         }
 371
 372 err:
 373         if (error)
 374                 ath_rx_cleanup(sc);
 375
 376         return error;
 377 }
 378
 379 void ath_rx_cleanup(struct ath_softc *sc)
 380 {
 381         struct ath_hw *ah = sc->sc_ah;
 382         struct ath_common *common = ath9k_hw_common(ah);
 383         struct sk_buff *skb;
 384         struct ath_buf *bf;
 385
 386         if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) {
 387                 ath_rx_edma_cleanup(sc);
 388                 return;
 389         } else {
 390                 list_for_each_entry(bf, &sc->rx.rxbuf, list) {
 391                         skb = bf->bf_mpdu;
 392                         if (skb) {
 393                                 dma_unmap_single(sc->dev, bf->bf_buf_addr,
 394                                                 common->rx_bufsize,
 395                                                 DMA_FROM_DEVICE);
 396                                 dev_kfree_skb(skb);
 397                                 bf->bf_buf_addr = 0;
 398                                 bf->bf_mpdu = NULL;
 399                         }
 400                 }
 401
 402                 if (sc->rx.rxdma.dd_desc_len != 0)
 403                         ath_descdma_cleanup(sc, &sc->rx.rxdma, &sc->rx.rxbuf);
 404         }
 405 }
 406
 407 /*
 408  * Calculate the receive filter according to the
 409  * operating mode and state:
 410  *
 411  * o always accept unicast, broadcast, and multicast traffic
 412  * o maintain current state of phy error reception (the hal
 413  *   may enable phy error frames for noise immunity work)
 414  * o probe request frames are accepted only when operating in
 415  *   hostap, adhoc, or monitor modes
 416  * o enable promiscuous mode according to the interface state
 417  * o accept beacons:
 418  *   - when operating in adhoc mode so the 802.11 layer creates
 419  *     node table entries for peers,
 420  *   - when operating in station mode for collecting rssi data when
 421  *     the station is otherwise quiet, or
 422  *   - when operating as a repeater so we see repeater-sta beacons
 423  *   - when scanning
 424  */
 425
 426 u32 ath_calcrxfilter(struct ath_softc *sc)
 427 {
 428 #define RX_FILTER_PRESERVE (ATH9K_RX_FILTER_PHYERR | ATH9K_RX_FILTER_PHYRADAR)
 429
 430         u32 rfilt;
 431
 432         rfilt = (ath9k_hw_getrxfilter(sc->sc_ah) & RX_FILTER_PRESERVE)
 433                 | ATH9K_RX_FILTER_UCAST | ATH9K_RX_FILTER_BCAST
 434                 | ATH9K_RX_FILTER_MCAST;
 435
 436         if (sc->rx.rxfilter & FIF_PROBE_REQ)
 437                 rfilt |= ATH9K_RX_FILTER_PROBEREQ;
 438
 439         /*
 440          * Set promiscuous mode when FIF_PROMISC_IN_BSS is enabled for station
 441          * mode interface or when in monitor mode. AP mode does not need this
 442          * since it receives all in-BSS frames anyway.
 443          */
 444         if (sc->sc_ah->is_monitoring)
 445                 rfilt |= ATH9K_RX_FILTER_PROM;
 446
 447         if (sc->rx.rxfilter & FIF_CONTROL)
 448                 rfilt |= ATH9K_RX_FILTER_CONTROL;
 449
 450         if ((sc->sc_ah->opmode == NL80211_IFTYPE_STATION) &&
 451             (sc->nvifs <= 1) &&
 452             !(sc->rx.rxfilter & FIF_BCN_PRBRESP_PROMISC))
 453                 rfilt |= ATH9K_RX_FILTER_MYBEACON;
 454         else
 455                 rfilt |= ATH9K_RX_FILTER_BEACON;
 456
 457         if ((sc->sc_ah->opmode == NL80211_IFTYPE_AP) ||
 458             (sc->rx.rxfilter & FIF_PSPOLL))
 459                 rfilt |= ATH9K_RX_FILTER_PSPOLL;
 460
 461         if (conf_is_ht(&sc->hw->conf))
 462                 rfilt |= ATH9K_RX_FILTER_COMP_BAR;
 463
 464         if (sc->nvifs > 1 || (sc->rx.rxfilter & FIF_OTHER_BSS)) {
 465                 /* The following may also be needed for other older chips */
 466                 if (sc->sc_ah->hw_version.macVersion == AR_SREV_VERSION_9160)
 467                         rfilt |= ATH9K_RX_FILTER_PROM;
 468                 rfilt |= ATH9K_RX_FILTER_MCAST_BCAST_ALL;
 469         }
 470
 471         return rfilt;
 472
 473 #undef RX_FILTER_PRESERVE
 474 }
 475
 476 int ath_startrecv(struct ath_softc *sc)
 477 {
 478         struct ath_hw *ah = sc->sc_ah;
 479         struct ath_buf *bf, *tbf;
 480
 481         if (ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) {
 482                 ath_edma_start_recv(sc);
 483                 return 0;
 484         }
 485
 486         spin_lock_bh(&sc->rx.rxbuflock);
 487         if (list_empty(&sc->rx.rxbuf))
 488                 goto start_recv;
 489
 490         sc->rx.rxlink = NULL;
 491         list_for_each_entry_safe(bf, tbf, &sc->rx.rxbuf, list) {
 492                 ath_rx_buf_link(sc, bf);
 493         }
 494
 495         /* We could have deleted elements so the list may be empty now */
 496         if (list_empty(&sc->rx.rxbuf))
 497                 goto start_recv;
 498
 499         bf = list_first_entry(&sc->rx.rxbuf, struct ath_buf, list);
 500         ath9k_hw_putrxbuf(ah, bf->bf_daddr);
 501         ath9k_hw_rxena(ah);
 502
 503 start_recv:
 504         ath_opmode_init(sc);
 505         ath9k_hw_startpcureceive(ah, (sc->sc_flags & SC_OP_OFFCHANNEL));
 506
 507         spin_unlock_bh(&sc->rx.rxbuflock);
 508
 509         return 0;
 510 }
 511
 512 bool ath_stoprecv(struct ath_softc *sc)
 513 {
 514         struct ath_hw *ah = sc->sc_ah;
 515         bool stopped, reset = false;
 516
 517         spin_lock_bh(&sc->rx.rxbuflock);
 518         ath9k_hw_abortpcurecv(ah);
 519         ath9k_hw_setrxfilter(ah, 0);
 520         stopped = ath9k_hw_stopdmarecv(ah, &reset);
 521
 522         if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA)
 523                 ath_edma_stop_recv(sc);
 524         else
 525                 sc->rx.rxlink = NULL;
 526         spin_unlock_bh(&sc->rx.rxbuflock);
 527
 528         if (!(ah->ah_flags & AH_UNPLUGGED) &&
 529             unlikely(!stopped)) {
 530                 ath_err(ath9k_hw_common(sc->sc_ah),
 531                         "Could not stop RX, we could be "
 532                         "confusing the DMA engine when we start RX up\n");
 533                 ATH_DBG_WARN_ON_ONCE(!stopped);
 534         }
 535         return stopped && !reset;
 536 }
 537
 538 void ath_flushrecv(struct ath_softc *sc)
 539 {
 540         sc->sc_flags |= SC_OP_RXFLUSH;
 541         if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA)
 542                 ath_rx_tasklet(sc, 1, true);
 543         ath_rx_tasklet(sc, 1, false);
 544         sc->sc_flags &= ~SC_OP_RXFLUSH;
 545 }
 546
 547 static bool ath_beacon_dtim_pending_cab(struct sk_buff *skb)
 548 {
 549         /* Check whether the Beacon frame has DTIM indicating buffered bc/mc */
 550         struct ieee80211_mgmt *mgmt;
 551         u8 *pos, *end, id, elen;
 552         struct ieee80211_tim_ie *tim;
 553
 554         mgmt = (struct ieee80211_mgmt *)skb->data;
 555         pos = mgmt->u.beacon.variable;
 556         end = skb->data + skb->len;
 557
 558         while (pos + 2 < end) {
 559                 id = *pos++;
 560                 elen = *pos++;
 561                 if (pos + elen > end)
 562                         break;
 563
 564                 if (id == WLAN_EID_TIM) {
 565                         if (elen < sizeof(*tim))
 566                                 break;
 567                         tim = (struct ieee80211_tim_ie *) pos;
 568                         if (tim->dtim_count != 0)
 569                                 break;
 570                         return tim->bitmap_ctrl & 0x01;
 571                 }
 572
 573                 pos += elen;
 574         }
 575
 576         return false;
 577 }
 578
 579 static void ath_rx_ps_beacon(struct ath_softc *sc, struct sk_buff *skb)
 580 {
 581         struct ieee80211_mgmt *mgmt;
 582         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 583
 584         if (skb->len < 24 + 8 + 2 + 2)
 585                 return;
 586
 587         mgmt = (struct ieee80211_mgmt *)skb->data;
 588         if (memcmp(common->curbssid, mgmt->bssid, ETH_ALEN) != 0) {
 589                 /* TODO:  This doesn't work well if you have stations
 590                  * associated to two different APs because curbssid
 591                  * is just the last AP that any of the stations associated
 592                  * with.
 593                  */
 594                 return; /* not from our current AP */
 595         }
 596
 597         sc->ps_flags &= ~PS_WAIT_FOR_BEACON;
 598
 599         if (sc->ps_flags & PS_BEACON_SYNC) {
 600                 sc->ps_flags &= ~PS_BEACON_SYNC;
 601                 ath_dbg(common, ATH_DBG_PS,
 602                         "Reconfigure Beacon timers based on timestamp from the AP\n");
 603                 ath_set_beacon(sc);
 604         }
 605
 606         if (ath_beacon_dtim_pending_cab(skb)) {
 607                 /*
 608                  * Remain awake waiting for buffered broadcast/multicast
 609                  * frames. If the last broadcast/multicast frame is not
 610                  * received properly, the next beacon frame will work as
 611                  * a backup trigger for returning into NETWORK SLEEP state,
 612                  * so we are waiting for it as well.
 613                  */
 614                 ath_dbg(common, ATH_DBG_PS,
 615                         "Received DTIM beacon indicating buffered broadcast/multicast frame(s)\n");
 616                 sc->ps_flags |= PS_WAIT_FOR_CAB | PS_WAIT_FOR_BEACON;
 617                 return;
 618         }
 619
 620         if (sc->ps_flags & PS_WAIT_FOR_CAB) {
 621                 /*
 622                  * This can happen if a broadcast frame is dropped or the AP
 623                  * fails to send a frame indicating that all CAB frames have
 624                  * been delivered.
 625                  */
 626                 sc->ps_flags &= ~PS_WAIT_FOR_CAB;
 627                 ath_dbg(common, ATH_DBG_PS,
 628                         "PS wait for CAB frames timed out\n");
 629         }
 630 }
 631
 632 static void ath_rx_ps(struct ath_softc *sc, struct sk_buff *skb)
 633 {
 634         struct ieee80211_hdr *hdr;
 635         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 636
 637         hdr = (struct ieee80211_hdr *)skb->data;
 638
 639         /* Process Beacon and CAB receive in PS state */
 640         if (((sc->ps_flags & PS_WAIT_FOR_BEACON) || ath9k_check_auto_sleep(sc))
 641             && ieee80211_is_beacon(hdr->frame_control))
 642                 ath_rx_ps_beacon(sc, skb);
 643         else if ((sc->ps_flags & PS_WAIT_FOR_CAB) &&
 644                  (ieee80211_is_data(hdr->frame_control) ||
 645                   ieee80211_is_action(hdr->frame_control)) &&
 646                  is_multicast_ether_addr(hdr->addr1) &&
 647                  !ieee80211_has_moredata(hdr->frame_control)) {
 648                 /*
 649                  * No more broadcast/multicast frames to be received at this
 650                  * point.
 651                  */
 652                 sc->ps_flags &= ~(PS_WAIT_FOR_CAB | PS_WAIT_FOR_BEACON);
 653                 ath_dbg(common, ATH_DBG_PS,
 654                         "All PS CAB frames received, back to sleep\n");
 655         } else if ((sc->ps_flags & PS_WAIT_FOR_PSPOLL_DATA) &&
 656                    !is_multicast_ether_addr(hdr->addr1) &&
 657                    !ieee80211_has_morefrags(hdr->frame_control)) {
 658                 sc->ps_flags &= ~PS_WAIT_FOR_PSPOLL_DATA;
 659                 ath_dbg(common, ATH_DBG_PS,
 660                         "Going back to sleep after having received PS-Poll data (0x%lx)\n",
 661                         sc->ps_flags & (PS_WAIT_FOR_BEACON |
 662                                         PS_WAIT_FOR_CAB |
 663                                         PS_WAIT_FOR_PSPOLL_DATA |
 664                                         PS_WAIT_FOR_TX_ACK));
 665         }
 666 }
 667
 668 static bool ath_edma_get_buffers(struct ath_softc *sc,
 669                                  enum ath9k_rx_qtype qtype)
 670 {
 671         struct ath_rx_edma *rx_edma = &sc->rx.rx_edma[qtype];
 672         struct ath_hw *ah = sc->sc_ah;
 673         struct ath_common *common = ath9k_hw_common(ah);
 674         struct sk_buff *skb;
 675         struct ath_buf *bf;
 676         int ret;
 677
 678         skb = skb_peek(&rx_edma->rx_fifo);
 679         if (!skb)
 680                 return false;
 681
 682         bf = SKB_CB_ATHBUF(skb);
 683         BUG_ON(!bf);
 684
 685         dma_sync_single_for_cpu(sc->dev, bf->bf_buf_addr,
 686                                 common->rx_bufsize, DMA_FROM_DEVICE);
 687
 688         ret = ath9k_hw_process_rxdesc_edma(ah, NULL, skb->data);
 689         if (ret == -EINPROGRESS) {
 690                 /*let device gain the buffer again*/
 691                 dma_sync_single_for_device(sc->dev, bf->bf_buf_addr,
 692                                 common->rx_bufsize, DMA_FROM_DEVICE);
 693                 return false;
 694         }
 695
 696         __skb_unlink(skb, &rx_edma->rx_fifo);
 697         if (ret == -EINVAL) {
 698                 /* corrupt descriptor, skip this one and the following one */
 699                 list_add_tail(&bf->list, &sc->rx.rxbuf);
 700                 ath_rx_edma_buf_link(sc, qtype);
 701                 skb = skb_peek(&rx_edma->rx_fifo);
 702                 if (!skb)
 703                         return true;
 704
 705                 bf = SKB_CB_ATHBUF(skb);
 706                 BUG_ON(!bf);
 707
 708                 __skb_unlink(skb, &rx_edma->rx_fifo);
 709                 list_add_tail(&bf->list, &sc->rx.rxbuf);
 710                 ath_rx_edma_buf_link(sc, qtype);
 711                 return true;
 712         }
 713         skb_queue_tail(&rx_edma->rx_buffers, skb);
 714
 715         return true;
 716 }
 717
 718 static struct ath_buf *ath_edma_get_next_rx_buf(struct ath_softc *sc,
 719                                                 struct ath_rx_status *rs,
 720                                                 enum ath9k_rx_qtype qtype)
 721 {
 722         struct ath_rx_edma *rx_edma = &sc->rx.rx_edma[qtype];
 723         struct sk_buff *skb;
 724         struct ath_buf *bf;
 725
 726         while (ath_edma_get_buffers(sc, qtype));
 727         skb = __skb_dequeue(&rx_edma->rx_buffers);
 728         if (!skb)
 729                 return NULL;
 730
 731         bf = SKB_CB_ATHBUF(skb);
 732         ath9k_hw_process_rxdesc_edma(sc->sc_ah, rs, skb->data);
 733         return bf;
 734 }
 735
 736 static struct ath_buf *ath_get_next_rx_buf(struct ath_softc *sc,
 737                                            struct ath_rx_status *rs)
 738 {
 739         struct ath_hw *ah = sc->sc_ah;
 740         struct ath_common *common = ath9k_hw_common(ah);
 741         struct ath_desc *ds;
 742         struct ath_buf *bf;
 743         int ret;
 744
 745         if (list_empty(&sc->rx.rxbuf)) {
 746                 sc->rx.rxlink = NULL;
 747                 return NULL;
 748         }
 749
 750         bf = list_first_entry(&sc->rx.rxbuf, struct ath_buf, list);
 751         ds = bf->bf_desc;
 752
 753         /*
 754          * Must provide the virtual address of the current
 755          * descriptor, the physical address, and the virtual
 756          * address of the next descriptor in the h/w chain.
 757          * This allows the HAL to look ahead to see if the
 758          * hardware is done with a descriptor by checking the
 759          * done bit in the following descriptor and the address
 760          * of the current descriptor the DMA engine is working
 761          * on.  All this is necessary because of our use of
 762          * a self-linked list to avoid rx overruns.
 763          */
 764         ret = ath9k_hw_rxprocdesc(ah, ds, rs);
 765         if (ret == -EINPROGRESS) {
 766                 struct ath_rx_status trs;
 767                 struct ath_buf *tbf;
 768                 struct ath_desc *tds;
 769
 770                 memset(&trs, 0, sizeof(trs));
 771                 if (list_is_last(&bf->list, &sc->rx.rxbuf)) {
 772                         sc->rx.rxlink = NULL;
 773                         return NULL;
 774                 }
 775
 776                 tbf = list_entry(bf->list.next, struct ath_buf, list);
 777
 778                 /*
 779                  * On some hardware the descriptor status words could
 780                  * get corrupted, including the done bit. Because of
 781                  * this, check if the next descriptor's done bit is
 782                  * set or not.
 783                  *
 784                  * If the next descriptor's done bit is set, the current
 785                  * descriptor has been corrupted. Force s/w to discard
 786                  * this descriptor and continue...
 787                  */
 788
 789                 tds = tbf->bf_desc;
 790                 ret = ath9k_hw_rxprocdesc(ah, tds, &trs);
 791                 if (ret == -EINPROGRESS)
 792                         return NULL;
 793         }
 794
 795         if (!bf->bf_mpdu)
 796                 return bf;
 797
 798         /*
 799          * Synchronize the DMA transfer with CPU before
 800          * 1. accessing the frame
 801          * 2. requeueing the same buffer to h/w
 802          */
 803         dma_sync_single_for_cpu(sc->dev, bf->bf_buf_addr,
 804                         common->rx_bufsize,
 805                         DMA_FROM_DEVICE);
 806
 807         return bf;
 808 }
 809
 810 /* Assumes you've already done the endian to CPU conversion */
 811 static bool ath9k_rx_accept(struct ath_common *common,
 812                             struct ieee80211_hdr *hdr,
 813                             struct ieee80211_rx_status *rxs,
 814                             struct ath_rx_status *rx_stats,
 815                             bool *decrypt_error)
 816 {
 817         bool is_mc, is_valid_tkip, strip_mic, mic_error;
 818         struct ath_hw *ah = common->ah;
 819         __le16 fc;
 820         u8 rx_status_len = ah->caps.rx_status_len;
 821
 822         fc = hdr->frame_control;
 823
 824         is_mc = !!is_multicast_ether_addr(hdr->addr1);
 825         is_valid_tkip = rx_stats->rs_keyix != ATH9K_RXKEYIX_INVALID &&
 826                 test_bit(rx_stats->rs_keyix, common->tkip_keymap);
 827         strip_mic = is_valid_tkip && ieee80211_is_data(fc) &&
 828                 !(rx_stats->rs_status &
 829                 (ATH9K_RXERR_DECRYPT | ATH9K_RXERR_CRC | ATH9K_RXERR_MIC));
 830
 831         if (!rx_stats->rs_datalen)
 832                 return false;
 833         /*
 834          * rs_status follows rs_datalen so if rs_datalen is too large
 835          * we can take a hint that hardware corrupted it, so ignore
 836          * those frames.
 837          */
 838         if (rx_stats->rs_datalen > (common->rx_bufsize - rx_status_len))
 839                 return false;
 840
 841         /* Only use error bits from the last fragment */
 842         if (rx_stats->rs_more)
 843                 return true;
 844
 845         mic_error = is_valid_tkip && !ieee80211_is_ctl(fc) &&
 846                 !ieee80211_has_morefrags(fc) &&
 847                 !(le16_to_cpu(hdr->seq_ctrl) & IEEE80211_SCTL_FRAG) &&
 848                 (rx_stats->rs_status & ATH9K_RXERR_MIC);
 849
 850         /*
 851          * The rx_stats->rs_status will not be set until the end of the
 852          * chained descriptors so it can be ignored if rs_more is set. The
 853          * rs_more will be false at the last element of the chained
 854          * descriptors.
 855          */
 856         if (rx_stats->rs_status != 0) {
 857                 if (rx_stats->rs_status & ATH9K_RXERR_CRC) {
 858                         rxs->flag |= RX_FLAG_FAILED_FCS_CRC;
 859                         mic_error = false;
 860                 }
 861                 if (rx_stats->rs_status & ATH9K_RXERR_PHY)
 862                         return false;
 863
 864                 if (rx_stats->rs_status & ATH9K_RXERR_DECRYPT) {
 865                         *decrypt_error = true;
 866                         mic_error = false;
 867                 }
 868
 869                 /*
 870                  * Reject error frames with the exception of
 871                  * decryption and MIC failures. For monitor mode,
 872                  * we also ignore the CRC error.
 873                  */
 874                 if (ah->is_monitoring) {
 875                         if (rx_stats->rs_status &
 876                             ~(ATH9K_RXERR_DECRYPT | ATH9K_RXERR_MIC |
 877                               ATH9K_RXERR_CRC))
 878                                 return false;
 879                 } else {
 880                         if (rx_stats->rs_status &
 881                             ~(ATH9K_RXERR_DECRYPT | ATH9K_RXERR_MIC)) {
 882                                 return false;
 883                         }
 884                 }
 885         }
 886
 887         /*
 888          * For unicast frames the MIC error bit can have false positives,
 889          * so all MIC error reports need to be validated in software.
 890          * False negatives are not common, so skip software verification
 891          * if the hardware considers the MIC valid.
 892          */
 893         if (strip_mic)
 894                 rxs->flag |= RX_FLAG_MMIC_STRIPPED;
 895         else if (is_mc && mic_error)
 896                 rxs->flag |= RX_FLAG_MMIC_ERROR;
 897
 898         return true;
 899 }
 900
 901 static int ath9k_process_rate(struct ath_common *common,
 902                               struct ieee80211_hw *hw,
 903                               struct ath_rx_status *rx_stats,
 904                               struct ieee80211_rx_status *rxs)
 905 {
 906         struct ieee80211_supported_band *sband;
 907         enum ieee80211_band band;
 908         unsigned int i = 0;
 909
 910         band = hw->conf.channel->band;
 911         sband = hw->wiphy->bands[band];
 912
 913         if (rx_stats->rs_rate & 0x80) {
 914                 /* HT rate */
 915                 rxs->flag |= RX_FLAG_HT;
 916                 if (rx_stats->rs_flags & ATH9K_RX_2040)
 917                         rxs->flag |= RX_FLAG_40MHZ;
 918                 if (rx_stats->rs_flags & ATH9K_RX_GI)
 919                         rxs->flag |= RX_FLAG_SHORT_GI;
 920                 rxs->rate_idx = rx_stats->rs_rate & 0x7f;
 921                 return 0;
 922         }
 923
 924         for (i = 0; i < sband->n_bitrates; i++) {
 925                 if (sband->bitrates[i].hw_value == rx_stats->rs_rate) {
 926                         rxs->rate_idx = i;
 927                         return 0;
 928                 }
 929                 if (sband->bitrates[i].hw_value_short == rx_stats->rs_rate) {
 930                         rxs->flag |= RX_FLAG_SHORTPRE;
 931                         rxs->rate_idx = i;
 932                         return 0;
 933                 }
 934         }
 935
 936         /*
 937          * No valid hardware bitrate found -- we should not get here
 938          * because hardware has already validated this frame as OK.
 939          */
 940         ath_dbg(common, ATH_DBG_ANY,
 941                 "unsupported hw bitrate detected 0x%02x using 1 Mbit\n",
 942                 rx_stats->rs_rate);
 943
 944         return -EINVAL;
 945 }
 946
 947 static void ath9k_process_rssi(struct ath_common *common,
 948                                struct ieee80211_hw *hw,
 949                                struct ieee80211_hdr *hdr,
 950                                struct ath_rx_status *rx_stats)
 951 {
 952         struct ath_softc *sc = hw->priv;
 953         struct ath_hw *ah = common->ah;
 954         int last_rssi;
 955
 956         if (!rx_stats->is_mybeacon ||
 957             ((ah->opmode != NL80211_IFTYPE_STATION) &&
 958              (ah->opmode != NL80211_IFTYPE_ADHOC)))
 959                 return;
 960
 961         if (rx_stats->rs_rssi != ATH9K_RSSI_BAD && !rx_stats->rs_moreaggr)
 962                 ATH_RSSI_LPF(sc->last_rssi, rx_stats->rs_rssi);
 963
 964         last_rssi = sc->last_rssi;
 965         if (likely(last_rssi != ATH_RSSI_DUMMY_MARKER))
 966                 rx_stats->rs_rssi = ATH_EP_RND(last_rssi,
 967                                               ATH_RSSI_EP_MULTIPLIER);
 968         if (rx_stats->rs_rssi < 0)
 969                 rx_stats->rs_rssi = 0;
 970
 971         /* Update Beacon RSSI, this is used by ANI. */
 972         ah->stats.avgbrssi = rx_stats->rs_rssi;
 973 }
 974
 975 /*
 976  * For Decrypt or Demic errors, we only mark packet status here and always push
 977  * up the frame up to let mac80211 handle the actual error case, be it no
 978  * decryption key or real decryption error. This let us keep statistics there.
 979  */
 980 static int ath9k_rx_skb_preprocess(struct ath_common *common,
 981                                    struct ieee80211_hw *hw,
 982                                    struct ieee80211_hdr *hdr,
 983                                    struct ath_rx_status *rx_stats,
 984                                    struct ieee80211_rx_status *rx_status,
 985                                    bool *decrypt_error)
 986 {
 987         struct ath_hw *ah = common->ah;
 988
 989         memset(rx_status, 0, sizeof(struct ieee80211_rx_status));
 990
 991         /*
 992          * everything but the rate is checked here, the rate check is done
 993          * separately to avoid doing two lookups for a rate for each frame.
 994          */
 995         if (!ath9k_rx_accept(common, hdr, rx_status, rx_stats, decrypt_error))
 996                 return -EINVAL;
 997
 998         /* Only use status info from the last fragment */
 999         if (rx_stats->rs_more)
1000                 return 0;
1001
1002         ath9k_process_rssi(common, hw, hdr, rx_stats);
1003
1004         if (ath9k_process_rate(common, hw, rx_stats, rx_status))
1005                 return -EINVAL;
1006
1007         rx_status->band = hw->conf.channel->band;
1008         rx_status->freq = hw->conf.channel->center_freq;
1009         rx_status->signal = ah->noise + rx_stats->rs_rssi;
1010         rx_status->antenna = rx_stats->rs_antenna;
1011         rx_status->flag |= RX_FLAG_MACTIME_MPDU;
1012
1013         return 0;
1014 }
1015
1016 static void ath9k_rx_skb_postprocess(struct ath_common *common,
1017                                      struct sk_buff *skb,
1018                                      struct ath_rx_status *rx_stats,
1019                                      struct ieee80211_rx_status *rxs,
1020                                      bool decrypt_error)
1021 {
1022         struct ath_hw *ah = common->ah;
1023         struct ieee80211_hdr *hdr;
1024         int hdrlen, padpos, padsize;
1025         u8 keyix;
1026         __le16 fc;
1027
1028         /* see if any padding is done by the hw and remove it */
1029         hdr = (struct ieee80211_hdr *) skb->data;
1030         hdrlen = ieee80211_get_hdrlen_from_skb(skb);
1031         fc = hdr->frame_control;
1032         padpos = ath9k_cmn_padpos(hdr->frame_control);
1033
1034         /* The MAC header is padded to have 32-bit boundary if the
1035          * packet payload is non-zero. The general calculation for
1036          * padsize would take into account odd header lengths:
1037          * padsize = (4 - padpos % 4) % 4; However, since only
1038          * even-length headers are used, padding can only be 0 or 2
1039          * bytes and we can optimize this a bit. In addition, we must
1040          * not try to remove padding from short control frames that do
1041          * not have payload. */
1042         padsize = padpos & 3;
1043         if (padsize && skb->len>=padpos+padsize+FCS_LEN) {
1044                 memmove(skb->data + padsize, skb->data, padpos);
1045                 skb_pull(skb, padsize);
1046         }
1047
1048         keyix = rx_stats->rs_keyix;
1049
1050         if (!(keyix == ATH9K_RXKEYIX_INVALID) && !decrypt_error &&
1051             ieee80211_has_protected(fc)) {
1052                 rxs->flag |= RX_FLAG_DECRYPTED;
1053         } else if (ieee80211_has_protected(fc)
1054                    && !decrypt_error && skb->len >= hdrlen + 4) {
1055                 keyix = skb->data[hdrlen + 3] >> 6;
1056
1057                 if (test_bit(keyix, common->keymap))
1058                         rxs->flag |= RX_FLAG_DECRYPTED;
1059         }
1060         if (ah->sw_mgmt_crypto &&
1061             (rxs->flag & RX_FLAG_DECRYPTED) &&
1062             ieee80211_is_mgmt(fc))
1063                 /* Use software decrypt for management frames. */
1064                 rxs->flag &= ~RX_FLAG_DECRYPTED;
1065 }
1066
1067 static void ath_lnaconf_alt_good_scan(struct ath_ant_comb *antcomb,
1068                                       struct ath_hw_antcomb_conf ant_conf,
1069                                       int main_rssi_avg)
1070 {
1071         antcomb->quick_scan_cnt = 0;
1072
1073         if (ant_conf.main_lna_conf == ATH_ANT_DIV_COMB_LNA2)
1074                 antcomb->rssi_lna2 = main_rssi_avg;
1075         else if (ant_conf.main_lna_conf == ATH_ANT_DIV_COMB_LNA1)
1076                 antcomb->rssi_lna1 = main_rssi_avg;
1077
1078         switch ((ant_conf.main_lna_conf << 4) | ant_conf.alt_lna_conf) {
1079         case 0x10: /* LNA2 A-B */
1080                 antcomb->main_conf = ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
1081                 antcomb->first_quick_scan_conf =
1082                         ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
1083                 antcomb->second_quick_scan_conf = ATH_ANT_DIV_COMB_LNA1;
1084                 break;
1085         case 0x20: /* LNA1 A-B */
1086                 antcomb->main_conf = ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
1087                 antcomb->first_quick_scan_conf =
1088                         ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
1089                 antcomb->second_quick_scan_conf = ATH_ANT_DIV_COMB_LNA2;
1090                 break;
1091         case 0x21: /* LNA1 LNA2 */
1092                 antcomb->main_conf = ATH_ANT_DIV_COMB_LNA2;
1093                 antcomb->first_quick_scan_conf =
1094                         ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
1095                 antcomb->second_quick_scan_conf =
1096                         ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
1097                 break;
1098         case 0x12: /* LNA2 LNA1 */
1099                 antcomb->main_conf = ATH_ANT_DIV_COMB_LNA1;
1100                 antcomb->first_quick_scan_conf =
1101                         ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
1102                 antcomb->second_quick_scan_conf =
1103                         ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
1104                 break;
1105         case 0x13: /* LNA2 A+B */
1106                 antcomb->main_conf = ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
1107                 antcomb->first_quick_scan_conf =
1108                         ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
1109                 antcomb->second_quick_scan_conf = ATH_ANT_DIV_COMB_LNA1;
1110                 break;
1111         case 0x23: /* LNA1 A+B */
1112                 antcomb->main_conf = ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
1113                 antcomb->first_quick_scan_conf =
1114                         ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
1115                 antcomb->second_quick_scan_conf = ATH_ANT_DIV_COMB_LNA2;
1116                 break;
1117         default:
1118                 break;
1119         }
1120 }
1121
1122 static void ath_select_ant_div_from_quick_scan(struct ath_ant_comb *antcomb,
1123                                 struct ath_hw_antcomb_conf *div_ant_conf,
1124                                 int main_rssi_avg, int alt_rssi_avg,
1125                                 int alt_ratio)
1126 {
1127         /* alt_good */
1128         switch (antcomb->quick_scan_cnt) {
1129         case 0:
1130                 /* set alt to main, and alt to first conf */
1131                 div_ant_conf->main_lna_conf = antcomb->main_conf;
1132                 div_ant_conf->alt_lna_conf = antcomb->first_quick_scan_conf;
1133                 break;
1134         case 1:
1135                 /* set alt to main, and alt to first conf */
1136                 div_ant_conf->main_lna_conf = antcomb->main_conf;
1137                 div_ant_conf->alt_lna_conf = antcomb->second_quick_scan_conf;
1138                 antcomb->rssi_first = main_rssi_avg;
1139                 antcomb->rssi_second = alt_rssi_avg;
1140
1141                 if (antcomb->main_conf == ATH_ANT_DIV_COMB_LNA1) {
1142                         /* main is LNA1 */
1143                         if (ath_is_alt_ant_ratio_better(alt_ratio,
1144                                                 ATH_ANT_DIV_COMB_LNA1_DELTA_HI,
1145                                                 ATH_ANT_DIV_COMB_LNA1_DELTA_LOW,
1146                                                 main_rssi_avg, alt_rssi_avg,
1147                                                 antcomb->total_pkt_count))
1148                                 antcomb->first_ratio = true;
1149                         else
1150                                 antcomb->first_ratio = false;
1151                 } else if (antcomb->main_conf == ATH_ANT_DIV_COMB_LNA2) {
1152                         if (ath_is_alt_ant_ratio_better(alt_ratio,
1153                                                 ATH_ANT_DIV_COMB_LNA1_DELTA_MID,
1154                                                 ATH_ANT_DIV_COMB_LNA1_DELTA_LOW,
1155                                                 main_rssi_avg, alt_rssi_avg,
1156                                                 antcomb->total_pkt_count))
1157                                 antcomb->first_ratio = true;
1158                         else
1159                                 antcomb->first_ratio = false;
1160                 } else {
1161                         if ((((alt_ratio >= ATH_ANT_DIV_COMB_ALT_ANT_RATIO2) &&
1162                             (alt_rssi_avg > main_rssi_avg +
1163                             ATH_ANT_DIV_COMB_LNA1_DELTA_HI)) ||
1164                             (alt_rssi_avg > main_rssi_avg)) &&
1165                             (antcomb->total_pkt_count > 50))
1166                                 antcomb->first_ratio = true;
1167                         else
1168                                 antcomb->first_ratio = false;
1169                 }
1170                 break;
1171         case 2:
1172                 antcomb->alt_good = false;
1173                 antcomb->scan_not_start = false;
1174                 antcomb->scan = false;
1175                 antcomb->rssi_first = main_rssi_avg;
1176                 antcomb->rssi_third = alt_rssi_avg;
1177
1178                 if (antcomb->second_quick_scan_conf == ATH_ANT_DIV_COMB_LNA1)
1179                         antcomb->rssi_lna1 = alt_rssi_avg;
1180                 else if (antcomb->second_quick_scan_conf ==
1181                          ATH_ANT_DIV_COMB_LNA2)
1182                         antcomb->rssi_lna2 = alt_rssi_avg;
1183                 else if (antcomb->second_quick_scan_conf ==
1184                          ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2) {
1185                         if (antcomb->main_conf == ATH_ANT_DIV_COMB_LNA2)
1186                                 antcomb->rssi_lna2 = main_rssi_avg;
1187                         else if (antcomb->main_conf == ATH_ANT_DIV_COMB_LNA1)
1188                                 antcomb->rssi_lna1 = main_rssi_avg;
1189                 }
1190
1191                 if (antcomb->rssi_lna2 > antcomb->rssi_lna1 +
1192                     ATH_ANT_DIV_COMB_LNA1_LNA2_SWITCH_DELTA)
1193                         div_ant_conf->main_lna_conf = ATH_ANT_DIV_COMB_LNA2;
1194                 else
1195                         div_ant_conf->main_lna_conf = ATH_ANT_DIV_COMB_LNA1;
1196
1197                 if (antcomb->main_conf == ATH_ANT_DIV_COMB_LNA1) {
1198                         if (ath_is_alt_ant_ratio_better(alt_ratio,
1199                                                 ATH_ANT_DIV_COMB_LNA1_DELTA_HI,
1200                                                 ATH_ANT_DIV_COMB_LNA1_DELTA_LOW,
1201                                                 main_rssi_avg, alt_rssi_avg,
1202                                                 antcomb->total_pkt_count))
1203                                 antcomb->second_ratio = true;
1204                         else
1205                                 antcomb->second_ratio = false;
1206                 } else if (antcomb->main_conf == ATH_ANT_DIV_COMB_LNA2) {
1207                         if (ath_is_alt_ant_ratio_better(alt_ratio,
1208                                                 ATH_ANT_DIV_COMB_LNA1_DELTA_MID,
1209                                                 ATH_ANT_DIV_COMB_LNA1_DELTA_LOW,
1210                                                 main_rssi_avg, alt_rssi_avg,
1211                                                 antcomb->total_pkt_count))
1212                                 antcomb->second_ratio = true;
1213                         else
1214                                 antcomb->second_ratio = false;
1215                 } else {
1216                         if ((((alt_ratio >= ATH_ANT_DIV_COMB_ALT_ANT_RATIO2) &&
1217                             (alt_rssi_avg > main_rssi_avg +
1218                             ATH_ANT_DIV_COMB_LNA1_DELTA_HI)) ||
1219                             (alt_rssi_avg > main_rssi_avg)) &&
1220                             (antcomb->total_pkt_count > 50))
1221                                 antcomb->second_ratio = true;
1222                         else
1223                                 antcomb->second_ratio = false;
1224                 }
1225
1226                 /* set alt to the conf with maximun ratio */
1227                 if (antcomb->first_ratio && antcomb->second_ratio) {
1228                         if (antcomb->rssi_second > antcomb->rssi_third) {
1229                                 /* first alt*/
1230                                 if ((antcomb->first_quick_scan_conf ==
1231                                     ATH_ANT_DIV_COMB_LNA1) ||
1232                                     (antcomb->first_quick_scan_conf ==
1233                                     ATH_ANT_DIV_COMB_LNA2))
1234                                         /* Set alt LNA1 or LNA2*/
1235                                         if (div_ant_conf->main_lna_conf ==
1236                                             ATH_ANT_DIV_COMB_LNA2)
1237                                                 div_ant_conf->alt_lna_conf =
1238                                                         ATH_ANT_DIV_COMB_LNA1;
1239                                         else
1240                                                 div_ant_conf->alt_lna_conf =
1241                                                         ATH_ANT_DIV_COMB_LNA2;
1242                                 else
1243                                         /* Set alt to A+B or A-B */
1244                                         div_ant_conf->alt_lna_conf =
1245                                                 antcomb->first_quick_scan_conf;
1246                         } else if ((antcomb->second_quick_scan_conf ==
1247                                    ATH_ANT_DIV_COMB_LNA1) ||
1248                                    (antcomb->second_quick_scan_conf ==
1249                                    ATH_ANT_DIV_COMB_LNA2)) {
1250                                 /* Set alt LNA1 or LNA2 */
1251                                 if (div_ant_conf->main_lna_conf ==
1252                                     ATH_ANT_DIV_COMB_LNA2)
1253                                         div_ant_conf->alt_lna_conf =
1254                                                 ATH_ANT_DIV_COMB_LNA1;
1255                                 else
1256                                         div_ant_conf->alt_lna_conf =
1257                                                 ATH_ANT_DIV_COMB_LNA2;
1258                         } else {
1259                                 /* Set alt to A+B or A-B */
1260                                 div_ant_conf->alt_lna_conf =
1261                                         antcomb->second_quick_scan_conf;
1262                         }
1263                 } else if (antcomb->first_ratio) {
1264                         /* first alt */
1265                         if ((antcomb->first_quick_scan_conf ==
1266                             ATH_ANT_DIV_COMB_LNA1) ||
1267                             (antcomb->first_quick_scan_conf ==
1268                             ATH_ANT_DIV_COMB_LNA2))
1269                                         /* Set alt LNA1 or LNA2 */
1270                                 if (div_ant_conf->main_lna_conf ==
1271                                     ATH_ANT_DIV_COMB_LNA2)
1272                                         div_ant_conf->alt_lna_conf =
1273                                                         ATH_ANT_DIV_COMB_LNA1;
1274                                 else
1275                                         div_ant_conf->alt_lna_conf =
1276                                                         ATH_ANT_DIV_COMB_LNA2;
1277                         else
1278                                 /* Set alt to A+B or A-B */
1279                                 div_ant_conf->alt_lna_conf =
1280                                                 antcomb->first_quick_scan_conf;
1281                 } else if (antcomb->second_ratio) {
1282                                 /* second alt */
1283                         if ((antcomb->second_quick_scan_conf ==
1284                             ATH_ANT_DIV_COMB_LNA1) ||
1285                             (antcomb->second_quick_scan_conf ==
1286                             ATH_ANT_DIV_COMB_LNA2))
1287                                 /* Set alt LNA1 or LNA2 */
1288                                 if (div_ant_conf->main_lna_conf ==
1289                                     ATH_ANT_DIV_COMB_LNA2)
1290                                         div_ant_conf->alt_lna_conf =
1291                                                 ATH_ANT_DIV_COMB_LNA1;
1292                                 else
1293                                         div_ant_conf->alt_lna_conf =
1294                                                 ATH_ANT_DIV_COMB_LNA2;
1295                         else
1296                                 /* Set alt to A+B or A-B */
1297                                 div_ant_conf->alt_lna_conf =
1298                                                 antcomb->second_quick_scan_conf;
1299                 } else {
1300                         /* main is largest */
1301                         if ((antcomb->main_conf == ATH_ANT_DIV_COMB_LNA1) ||
1302                             (antcomb->main_conf == ATH_ANT_DIV_COMB_LNA2))
1303                                 /* Set alt LNA1 or LNA2 */
1304                                 if (div_ant_conf->main_lna_conf ==
1305                                     ATH_ANT_DIV_COMB_LNA2)
1306                                         div_ant_conf->alt_lna_conf =
1307                                                         ATH_ANT_DIV_COMB_LNA1;
1308                                 else
1309                                         div_ant_conf->alt_lna_conf =
1310                                                         ATH_ANT_DIV_COMB_LNA2;
1311                         else
1312                                 /* Set alt to A+B or A-B */
1313                                 div_ant_conf->alt_lna_conf = antcomb->main_conf;
1314                 }
1315                 break;
1316         default:
1317                 break;
1318         }
1319 }
1320
1321 static void ath_ant_div_conf_fast_divbias(struct ath_hw_antcomb_conf *ant_conf,
1322                 struct ath_ant_comb *antcomb, int alt_ratio)
1323 {
1324         if (ant_conf->div_group == 0) {
1325                 /* Adjust the fast_div_bias based on main and alt lna conf */
1326                 switch ((ant_conf->main_lna_conf << 4) |
1327                                 ant_conf->alt_lna_conf) {
1328                 case 0x01: /* A-B LNA2 */
1329                         ant_conf->fast_div_bias = 0x3b;
1330                         break;
1331                 case 0x02: /* A-B LNA1 */
1332                         ant_conf->fast_div_bias = 0x3d;
1333                         break;
1334                 case 0x03: /* A-B A+B */
1335                         ant_conf->fast_div_bias = 0x1;
1336                         break;
1337                 case 0x10: /* LNA2 A-B */
1338                         ant_conf->fast_div_bias = 0x7;
1339                         break;
1340                 case 0x12: /* LNA2 LNA1 */
1341                         ant_conf->fast_div_bias = 0x2;
1342                         break;
1343                 case 0x13: /* LNA2 A+B */
1344                         ant_conf->fast_div_bias = 0x7;
1345                         break;
1346                 case 0x20: /* LNA1 A-B */
1347                         ant_conf->fast_div_bias = 0x6;
1348                         break;
1349                 case 0x21: /* LNA1 LNA2 */
1350                         ant_conf->fast_div_bias = 0x0;
1351                         break;
1352                 case 0x23: /* LNA1 A+B */
1353                         ant_conf->fast_div_bias = 0x6;
1354                         break;
1355                 case 0x30: /* A+B A-B */
1356                         ant_conf->fast_div_bias = 0x1;
1357                         break;
1358                 case 0x31: /* A+B LNA2 */
1359                         ant_conf->fast_div_bias = 0x3b;
1360                         break;
1361                 case 0x32: /* A+B LNA1 */
1362                         ant_conf->fast_div_bias = 0x3d;
1363                         break;
1364                 default:
1365                         break;
1366                 }
1367         } else if (ant_conf->div_group == 1) {
1368                 /* Adjust the fast_div_bias based on main and alt_lna_conf */
1369                 switch ((ant_conf->main_lna_conf << 4) |
1370                         ant_conf->alt_lna_conf) {
1371                 case 0x01: /* A-B LNA2 */
1372                         ant_conf->fast_div_bias = 0x1;
1373                         ant_conf->main_gaintb = 0;
1374                         ant_conf->alt_gaintb = 0;
1375                         break;
1376                 case 0x02: /* A-B LNA1 */
1377                         ant_conf->fast_div_bias = 0x1;
1378                         ant_conf->main_gaintb = 0;
1379                         ant_conf->alt_gaintb = 0;
1380                         break;
1381                 case 0x03: /* A-B A+B */
1382                         ant_conf->fast_div_bias = 0x1;
1383                         ant_conf->main_gaintb = 0;
1384                         ant_conf->alt_gaintb = 0;
1385                         break;
1386                 case 0x10: /* LNA2 A-B */
1387                         if (!(antcomb->scan) &&
1388                             (alt_ratio > ATH_ANT_DIV_COMB_ALT_ANT_RATIO))
1389                                 ant_conf->fast_div_bias = 0x3f;
1390                         else
1391                                 ant_conf->fast_div_bias = 0x1;
1392                         ant_conf->main_gaintb = 0;
1393                         ant_conf->alt_gaintb = 0;
1394                         break;
1395                 case 0x12: /* LNA2 LNA1 */
1396                         ant_conf->fast_div_bias = 0x1;
1397                         ant_conf->main_gaintb = 0;
1398                         ant_conf->alt_gaintb = 0;
1399                         break;
1400                 case 0x13: /* LNA2 A+B */
1401                         if (!(antcomb->scan) &&
1402                             (alt_ratio > ATH_ANT_DIV_COMB_ALT_ANT_RATIO))
1403                                 ant_conf->fast_div_bias = 0x3f;
1404                         else
1405                                 ant_conf->fast_div_bias = 0x1;
1406                         ant_conf->main_gaintb = 0;
1407                         ant_conf->alt_gaintb = 0;
1408                         break;
1409                 case 0x20: /* LNA1 A-B */
1410                         if (!(antcomb->scan) &&
1411                             (alt_ratio > ATH_ANT_DIV_COMB_ALT_ANT_RATIO))
1412                                 ant_conf->fast_div_bias = 0x3f;
1413                         else
1414                                 ant_conf->fast_div_bias = 0x1;
1415                         ant_conf->main_gaintb = 0;
1416                         ant_conf->alt_gaintb = 0;
1417                         break;
1418                 case 0x21: /* LNA1 LNA2 */
1419                         ant_conf->fast_div_bias = 0x1;
1420                         ant_conf->main_gaintb = 0;
1421                         ant_conf->alt_gaintb = 0;
1422                         break;
1423                 case 0x23: /* LNA1 A+B */
1424                         if (!(antcomb->scan) &&
1425                             (alt_ratio > ATH_ANT_DIV_COMB_ALT_ANT_RATIO))
1426                                 ant_conf->fast_div_bias = 0x3f;
1427                         else
1428                                 ant_conf->fast_div_bias = 0x1;
1429                         ant_conf->main_gaintb = 0;
1430                         ant_conf->alt_gaintb = 0;
1431                         break;
1432                 case 0x30: /* A+B A-B */
1433                         ant_conf->fast_div_bias = 0x1;
1434                         ant_conf->main_gaintb = 0;
1435                         ant_conf->alt_gaintb = 0;
1436                         break;
1437                 case 0x31: /* A+B LNA2 */
1438                         ant_conf->fast_div_bias = 0x1;
1439                         ant_conf->main_gaintb = 0;
1440                         ant_conf->alt_gaintb = 0;
1441                         break;
1442                 case 0x32: /* A+B LNA1 */
1443                         ant_conf->fast_div_bias = 0x1;
1444                         ant_conf->main_gaintb = 0;
1445                         ant_conf->alt_gaintb = 0;
1446                         break;
1447                 default:
1448                         break;
1449                 }
1450         } else if (ant_conf->div_group == 2) {
1451                 /* Adjust the fast_div_bias based on main and alt_lna_conf */
1452                 switch ((ant_conf->main_lna_conf << 4) |
1453                                 ant_conf->alt_lna_conf) {
1454                 case 0x01: /* A-B LNA2 */
1455                         ant_conf->fast_div_bias = 0x1;
1456                         ant_conf->main_gaintb = 0;
1457                         ant_conf->alt_gaintb = 0;
1458                         break;
1459                 case 0x02: /* A-B LNA1 */
1460                         ant_conf->fast_div_bias = 0x1;
1461                         ant_conf->main_gaintb = 0;
1462                         ant_conf->alt_gaintb = 0;
1463                         break;
1464                 case 0x03: /* A-B A+B */
1465                         ant_conf->fast_div_bias = 0x1;
1466                         ant_conf->main_gaintb = 0;
1467                         ant_conf->alt_gaintb = 0;
1468                         break;
1469                 case 0x10: /* LNA2 A-B */
1470                         if (!(antcomb->scan) &&
1471                                 (alt_ratio > ATH_ANT_DIV_COMB_ALT_ANT_RATIO))
1472                                 ant_conf->fast_div_bias = 0x1;
1473                         else
1474                                 ant_conf->fast_div_bias = 0x2;
1475                         ant_conf->main_gaintb = 0;
1476                         ant_conf->alt_gaintb = 0;
1477                         break;
1478                 case 0x12: /* LNA2 LNA1 */
1479                         ant_conf->fast_div_bias = 0x1;
1480                         ant_conf->main_gaintb = 0;
1481                         ant_conf->alt_gaintb = 0;
1482                         break;
1483                 case 0x13: /* LNA2 A+B */
1484                         if (!(antcomb->scan) &&
1485                                 (alt_ratio > ATH_ANT_DIV_COMB_ALT_ANT_RATIO))
1486                                 ant_conf->fast_div_bias = 0x1;
1487                         else
1488                                 ant_conf->fast_div_bias = 0x2;
1489                         ant_conf->main_gaintb = 0;
1490                         ant_conf->alt_gaintb = 0;
1491                         break;
1492                 case 0x20: /* LNA1 A-B */
1493                         if (!(antcomb->scan) &&
1494                                 (alt_ratio > ATH_ANT_DIV_COMB_ALT_ANT_RATIO))
1495                                 ant_conf->fast_div_bias = 0x1;
1496                         else
1497                                 ant_conf->fast_div_bias = 0x2;
1498                         ant_conf->main_gaintb = 0;
1499                         ant_conf->alt_gaintb = 0;
1500                         break;
1501                 case 0x21: /* LNA1 LNA2 */
1502                         ant_conf->fast_div_bias = 0x1;
1503                         ant_conf->main_gaintb = 0;
1504                         ant_conf->alt_gaintb = 0;
1505                         break;
1506                 case 0x23: /* LNA1 A+B */
1507                         if (!(antcomb->scan) &&
1508                                 (alt_ratio > ATH_ANT_DIV_COMB_ALT_ANT_RATIO))
1509                                 ant_conf->fast_div_bias = 0x1;
1510                         else
1511                                 ant_conf->fast_div_bias = 0x2;
1512                         ant_conf->main_gaintb = 0;
1513                         ant_conf->alt_gaintb = 0;
1514                         break;
1515                 case 0x30: /* A+B A-B */
1516                         ant_conf->fast_div_bias = 0x1;
1517                         ant_conf->main_gaintb = 0;
1518                         ant_conf->alt_gaintb = 0;
1519                         break;
1520                 case 0x31: /* A+B LNA2 */
1521                         ant_conf->fast_div_bias = 0x1;
1522                         ant_conf->main_gaintb = 0;
1523                         ant_conf->alt_gaintb = 0;
1524                         break;
1525                 case 0x32: /* A+B LNA1 */
1526                         ant_conf->fast_div_bias = 0x1;
1527                         ant_conf->main_gaintb = 0;
1528                         ant_conf->alt_gaintb = 0;
1529                         break;
1530                 default:
1531                         break;
1532                 }
1533         }
1534 }
1535
1536 /* Antenna diversity and combining */
1537 static void ath_ant_comb_scan(struct ath_softc *sc, struct ath_rx_status *rs)
1538 {
1539         struct ath_hw_antcomb_conf div_ant_conf;
1540         struct ath_ant_comb *antcomb = &sc->ant_comb;
1541         int alt_ratio = 0, alt_rssi_avg = 0, main_rssi_avg = 0, curr_alt_set;
1542         int curr_main_set;
1543         int main_rssi = rs->rs_rssi_ctl0;
1544         int alt_rssi = rs->rs_rssi_ctl1;
1545         int rx_ant_conf,  main_ant_conf;
1546         bool short_scan = false;
1547
1548         rx_ant_conf = (rs->rs_rssi_ctl2 >> ATH_ANT_RX_CURRENT_SHIFT) &
1549                        ATH_ANT_RX_MASK;
1550         main_ant_conf = (rs->rs_rssi_ctl2 >> ATH_ANT_RX_MAIN_SHIFT) &
1551                          ATH_ANT_RX_MASK;
1552
1553         /* Record packet only when both main_rssi and  alt_rssi is positive */
1554         if (main_rssi > 0 && alt_rssi > 0) {
1555                 antcomb->total_pkt_count++;
1556                 antcomb->main_total_rssi += main_rssi;
1557                 antcomb->alt_total_rssi  += alt_rssi;
1558                 if (main_ant_conf == rx_ant_conf)
1559                         antcomb->main_recv_cnt++;
1560                 else
1561                         antcomb->alt_recv_cnt++;
1562         }
1563
1564         /* Short scan check */
1565         if (antcomb->scan && antcomb->alt_good) {
1566                 if (time_after(jiffies, antcomb->scan_start_time +
1567                     msecs_to_jiffies(ATH_ANT_DIV_COMB_SHORT_SCAN_INTR)))
1568                         short_scan = true;
1569                 else
1570                         if (antcomb->total_pkt_count ==
1571                             ATH_ANT_DIV_COMB_SHORT_SCAN_PKTCOUNT) {
1572                                 alt_ratio = ((antcomb->alt_recv_cnt * 100) /
1573                                             antcomb->total_pkt_count);
1574                                 if (alt_ratio < ATH_ANT_DIV_COMB_ALT_ANT_RATIO)
1575                                         short_scan = true;
1576                         }
1577         }
1578
1579         if (((antcomb->total_pkt_count < ATH_ANT_DIV_COMB_MAX_PKTCOUNT) ||
1580             rs->rs_moreaggr) && !short_scan)
1581                 return;
1582
1583         if (antcomb->total_pkt_count) {
1584                 alt_ratio = ((antcomb->alt_recv_cnt * 100) /
1585                              antcomb->total_pkt_count);
1586                 main_rssi_avg = (antcomb->main_total_rssi /
1587                                  antcomb->total_pkt_count);
1588                 alt_rssi_avg = (antcomb->alt_total_rssi /
1589                                  antcomb->total_pkt_count);
1590         }
1591
1592
1593         ath9k_hw_antdiv_comb_conf_get(sc->sc_ah, &div_ant_conf);
1594         curr_alt_set = div_ant_conf.alt_lna_conf;
1595         curr_main_set = div_ant_conf.main_lna_conf;
1596
1597         antcomb->count++;
1598
1599         if (antcomb->count == ATH_ANT_DIV_COMB_MAX_COUNT) {
1600                 if (alt_ratio > ATH_ANT_DIV_COMB_ALT_ANT_RATIO) {
1601                         ath_lnaconf_alt_good_scan(antcomb, div_ant_conf,
1602                                                   main_rssi_avg);
1603                         antcomb->alt_good = true;
1604                 } else {
1605                         antcomb->alt_good = false;
1606                 }
1607
1608                 antcomb->count = 0;
1609                 antcomb->scan = true;
1610                 antcomb->scan_not_start = true;
1611         }
1612
1613         if (!antcomb->scan) {
1614                 if (ath_ant_div_comb_alt_check(div_ant_conf.div_group,
1615                                         alt_ratio, curr_main_set, curr_alt_set,
1616                                         alt_rssi_avg, main_rssi_avg)) {
1617                         if (curr_alt_set == ATH_ANT_DIV_COMB_LNA2) {
1618                                 /* Switch main and alt LNA */
1619                                 div_ant_conf.main_lna_conf =
1620                                                 ATH_ANT_DIV_COMB_LNA2;
1621                                 div_ant_conf.alt_lna_conf  =
1622                                                 ATH_ANT_DIV_COMB_LNA1;
1623                         } else if (curr_alt_set == ATH_ANT_DIV_COMB_LNA1) {
1624                                 div_ant_conf.main_lna_conf =
1625                                                 ATH_ANT_DIV_COMB_LNA1;
1626                                 div_ant_conf.alt_lna_conf  =
1627                                                 ATH_ANT_DIV_COMB_LNA2;
1628                         }
1629
1630                         goto div_comb_done;
1631                 } else if ((curr_alt_set != ATH_ANT_DIV_COMB_LNA1) &&
1632                            (curr_alt_set != ATH_ANT_DIV_COMB_LNA2)) {
1633                         /* Set alt to another LNA */
1634                         if (curr_main_set == ATH_ANT_DIV_COMB_LNA2)
1635                                 div_ant_conf.alt_lna_conf =
1636                                                 ATH_ANT_DIV_COMB_LNA1;
1637                         else if (curr_main_set == ATH_ANT_DIV_COMB_LNA1)
1638                                 div_ant_conf.alt_lna_conf =
1639                                                 ATH_ANT_DIV_COMB_LNA2;
1640
1641                         goto div_comb_done;
1642                 }
1643
1644                 if ((alt_rssi_avg < (main_rssi_avg +
1645                                                 div_ant_conf.lna1_lna2_delta)))
1646                         goto div_comb_done;
1647         }
1648
1649         if (!antcomb->scan_not_start) {
1650                 switch (curr_alt_set) {
1651                 case ATH_ANT_DIV_COMB_LNA2:
1652                         antcomb->rssi_lna2 = alt_rssi_avg;
1653                         antcomb->rssi_lna1 = main_rssi_avg;
1654                         antcomb->scan = true;
1655                         /* set to A+B */
1656                         div_ant_conf.main_lna_conf =
1657                                 ATH_ANT_DIV_COMB_LNA1;
1658                         div_ant_conf.alt_lna_conf  =
1659                                 ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
1660                         break;
1661                 case ATH_ANT_DIV_COMB_LNA1:
1662                         antcomb->rssi_lna1 = alt_rssi_avg;
1663                         antcomb->rssi_lna2 = main_rssi_avg;
1664                         antcomb->scan = true;
1665                         /* set to A+B */
1666                         div_ant_conf.main_lna_conf = ATH_ANT_DIV_COMB_LNA2;
1667                         div_ant_conf.alt_lna_conf  =
1668                                 ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
1669                         break;
1670                 case ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2:
1671                         antcomb->rssi_add = alt_rssi_avg;
1672                         antcomb->scan = true;
1673                         /* set to A-B */
1674                         div_ant_conf.alt_lna_conf =
1675                                 ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
1676                         break;
1677                 case ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2:
1678                         antcomb->rssi_sub = alt_rssi_avg;
1679                         antcomb->scan = false;
1680                         if (antcomb->rssi_lna2 >
1681                             (antcomb->rssi_lna1 +
1682                             ATH_ANT_DIV_COMB_LNA1_LNA2_SWITCH_DELTA)) {
1683                                 /* use LNA2 as main LNA */
1684                                 if ((antcomb->rssi_add > antcomb->rssi_lna1) &&
1685                                     (antcomb->rssi_add > antcomb->rssi_sub)) {
1686                                         /* set to A+B */
1687                                         div_ant_conf.main_lna_conf =
1688                                                 ATH_ANT_DIV_COMB_LNA2;
1689                                         div_ant_conf.alt_lna_conf  =
1690                                                 ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
1691                                 } else if (antcomb->rssi_sub >
1692                                            antcomb->rssi_lna1) {
1693                                         /* set to A-B */
1694                                         div_ant_conf.main_lna_conf =
1695                                                 ATH_ANT_DIV_COMB_LNA2;
1696                                         div_ant_conf.alt_lna_conf =
1697                                                 ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
1698                                 } else {
1699                                         /* set to LNA1 */
1700                                         div_ant_conf.main_lna_conf =
1701                                                 ATH_ANT_DIV_COMB_LNA2;
1702                                         div_ant_conf.alt_lna_conf =
1703                                                 ATH_ANT_DIV_COMB_LNA1;
1704                                 }
1705                         } else {
1706                                 /* use LNA1 as main LNA */
1707                                 if ((antcomb->rssi_add > antcomb->rssi_lna2) &&
1708                                     (antcomb->rssi_add > antcomb->rssi_sub)) {
1709                                         /* set to A+B */
1710                                         div_ant_conf.main_lna_conf =
1711                                                 ATH_ANT_DIV_COMB_LNA1;
1712                                         div_ant_conf.alt_lna_conf  =
1713                                                 ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
1714                                 } else if (antcomb->rssi_sub >
1715                                            antcomb->rssi_lna1) {
1716                                         /* set to A-B */
1717                                         div_ant_conf.main_lna_conf =
1718                                                 ATH_ANT_DIV_COMB_LNA1;
1719                                         div_ant_conf.alt_lna_conf =
1720                                                 ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
1721                                 } else {
1722                                         /* set to LNA2 */
1723                                         div_ant_conf.main_lna_conf =
1724                                                 ATH_ANT_DIV_COMB_LNA1;
1725                                         div_ant_conf.alt_lna_conf =
1726                                                 ATH_ANT_DIV_COMB_LNA2;
1727                                 }
1728                         }
1729                         break;
1730                 default:
1731                         break;
1732                 }
1733         } else {
1734                 if (!antcomb->alt_good) {
1735                         antcomb->scan_not_start = false;
1736                         /* Set alt to another LNA */
1737                         if (curr_main_set == ATH_ANT_DIV_COMB_LNA2) {
1738                                 div_ant_conf.main_lna_conf =
1739                                                 ATH_ANT_DIV_COMB_LNA2;
1740                                 div_ant_conf.alt_lna_conf =
1741                                                 ATH_ANT_DIV_COMB_LNA1;
1742                         } else if (curr_main_set == ATH_ANT_DIV_COMB_LNA1) {
1743                                 div_ant_conf.main_lna_conf =
1744                                                 ATH_ANT_DIV_COMB_LNA1;
1745                                 div_ant_conf.alt_lna_conf =
1746                                                 ATH_ANT_DIV_COMB_LNA2;
1747                         }
1748                         goto div_comb_done;
1749                 }
1750         }
1751
1752         ath_select_ant_div_from_quick_scan(antcomb, &div_ant_conf,
1753                                            main_rssi_avg, alt_rssi_avg,
1754                                            alt_ratio);
1755
1756         antcomb->quick_scan_cnt++;
1757
1758 div_comb_done:
1759         ath_ant_div_conf_fast_divbias(&div_ant_conf, antcomb, alt_ratio);
1760         ath9k_hw_antdiv_comb_conf_set(sc->sc_ah, &div_ant_conf);
1761
1762         antcomb->scan_start_time = jiffies;
1763         antcomb->total_pkt_count = 0;
1764         antcomb->main_total_rssi = 0;
1765         antcomb->alt_total_rssi = 0;
1766         antcomb->main_recv_cnt = 0;
1767         antcomb->alt_recv_cnt = 0;
1768 }
1769
1770 int ath_rx_tasklet(struct ath_softc *sc, int flush, bool hp)
1771 {
1772         struct ath_buf *bf;
1773         struct sk_buff *skb = NULL, *requeue_skb, *hdr_skb;
1774         struct ieee80211_rx_status *rxs;
1775         struct ath_hw *ah = sc->sc_ah;
1776         struct ath_common *common = ath9k_hw_common(ah);
1777         struct ieee80211_hw *hw = sc->hw;
1778         struct ieee80211_hdr *hdr;
1779         int retval;
1780         bool decrypt_error = false;
1781         struct ath_rx_status rs;
1782         enum ath9k_rx_qtype qtype;
1783         bool edma = !!(ah->caps.hw_caps & ATH9K_HW_CAP_EDMA);
1784         int dma_type;
1785         u8 rx_status_len = ah->caps.rx_status_len;
1786         u64 tsf = 0;
1787         u32 tsf_lower = 0;
1788         unsigned long flags;
1789
1790         if (edma)
1791                 dma_type = DMA_BIDIRECTIONAL;
1792         else
1793                 dma_type = DMA_FROM_DEVICE;
1794
1795         qtype = hp ? ATH9K_RX_QUEUE_HP : ATH9K_RX_QUEUE_LP;
1796         spin_lock_bh(&sc->rx.rxbuflock);
1797
1798         tsf = ath9k_hw_gettsf64(ah);
1799         tsf_lower = tsf & 0xffffffff;
1800
1801         do {
1802                 /* If handling rx interrupt and flush is in progress => exit */
1803                 if ((sc->sc_flags & SC_OP_RXFLUSH) && (flush == 0))
1804                         break;
1805
1806                 memset(&rs, 0, sizeof(rs));
1807                 if (edma)
1808                         bf = ath_edma_get_next_rx_buf(sc, &rs, qtype);
1809                 else
1810                         bf = ath_get_next_rx_buf(sc, &rs);
1811
1812                 if (!bf)
1813                         break;
1814
1815                 skb = bf->bf_mpdu;
1816                 if (!skb)
1817                         continue;
1818
1819                 /*
1820                  * Take frame header from the first fragment and RX status from
1821                  * the last one.
1822                  */
1823                 if (sc->rx.frag)
1824                         hdr_skb = sc->rx.frag;
1825                 else
1826                         hdr_skb = skb;
1827
1828                 hdr = (struct ieee80211_hdr *) (hdr_skb->data + rx_status_len);
1829                 rxs = IEEE80211_SKB_RXCB(hdr_skb);
1830                 if (ieee80211_is_beacon(hdr->frame_control) &&
1831                     !compare_ether_addr(hdr->addr3, common->curbssid))
1832                         rs.is_mybeacon = true;
1833                 else
1834                         rs.is_mybeacon = false;
1835
1836                 ath_debug_stat_rx(sc, &rs);
1837
1838                 /*
1839                  * If we're asked to flush receive queue, directly
1840                  * chain it back at the queue without processing it.
1841                  */
1842                 if (flush)
1843                         goto requeue_drop_frag;
1844
1845                 retval = ath9k_rx_skb_preprocess(common, hw, hdr, &rs,
1846                                                  rxs, &decrypt_error);
1847                 if (retval)
1848                         goto requeue_drop_frag;
1849
1850                 rxs->mactime = (tsf & ~0xffffffffULL) | rs.rs_tstamp;
1851                 if (rs.rs_tstamp > tsf_lower &&
1852                     unlikely(rs.rs_tstamp - tsf_lower > 0x10000000))
1853                         rxs->mactime -= 0x100000000ULL;
1854
1855                 if (rs.rs_tstamp < tsf_lower &&
1856                     unlikely(tsf_lower - rs.rs_tstamp > 0x10000000))
1857                         rxs->mactime += 0x100000000ULL;
1858
1859                 /* Ensure we always have an skb to requeue once we are done
1860                  * processing the current buffer's skb */
1861                 requeue_skb = ath_rxbuf_alloc(common, common->rx_bufsize, GFP_ATOMIC);
1862
1863                 /* If there is no memory we ignore the current RX'd frame,
1864                  * tell hardware it can give us a new frame using the old
1865                  * skb and put it at the tail of the sc->rx.rxbuf list for
1866                  * processing. */
1867                 if (!requeue_skb)
1868                         goto requeue_drop_frag;
1869
1870                 /* Unmap the frame */
1871                 dma_unmap_single(sc->dev, bf->bf_buf_addr,
1872                                  common->rx_bufsize,
1873                                  dma_type);
1874
1875                 skb_put(skb, rs.rs_datalen + ah->caps.rx_status_len);
1876                 if (ah->caps.rx_status_len)
1877                         skb_pull(skb, ah->caps.rx_status_len);
1878
1879                 if (!rs.rs_more)
1880                         ath9k_rx_skb_postprocess(common, hdr_skb, &rs,
1881                                                  rxs, decrypt_error);
1882
1883                 /* We will now give hardware our shiny new allocated skb */
1884                 bf->bf_mpdu = requeue_skb;
1885                 bf->bf_buf_addr = dma_map_single(sc->dev, requeue_skb->data,
1886                                                  common->rx_bufsize,
1887                                                  dma_type);
1888                 if (unlikely(dma_mapping_error(sc->dev,
1889                           bf->bf_buf_addr))) {
1890                         dev_kfree_skb_any(requeue_skb);
1891                         bf->bf_mpdu = NULL;
1892                         bf->bf_buf_addr = 0;
1893                         ath_err(common, "dma_mapping_error() on RX\n");
1894                         ieee80211_rx(hw, skb);
1895                         break;
1896                 }
1897
1898                 if (rs.rs_more) {
1899                         /*
1900                          * rs_more indicates chained descriptors which can be
1901                          * used to link buffers together for a sort of
1902                          * scatter-gather operation.
1903                          */
1904                         if (sc->rx.frag) {
1905                                 /* too many fragments - cannot handle frame */
1906                                 dev_kfree_skb_any(sc->rx.frag);
1907                                 dev_kfree_skb_any(skb);
1908                                 skb = NULL;
1909                         }
1910                         sc->rx.frag = skb;
1911                         goto requeue;
1912                 }
1913
1914                 if (sc->rx.frag) {
1915                         int space = skb->len - skb_tailroom(hdr_skb);
1916
1917                         sc->rx.frag = NULL;
1918
1919                         if (pskb_expand_head(hdr_skb, 0, space, GFP_ATOMIC) < 0) {
1920                                 dev_kfree_skb(skb);
1921                                 goto requeue_drop_frag;
1922                         }
1923
1924                         skb_copy_from_linear_data(skb, skb_put(hdr_skb, skb->len),
1925                                                   skb->len);
1926                         dev_kfree_skb_any(skb);
1927                         skb = hdr_skb;
1928                 }
1929
1930                 /*
1931                  * change the default rx antenna if rx diversity chooses the
1932                  * other antenna 3 times in a row.
1933                  */
1934                 if (sc->rx.defant != rs.rs_antenna) {
1935                         if (++sc->rx.rxotherant >= 3)
1936                                 ath_setdefantenna(sc, rs.rs_antenna);
1937                 } else {
1938                         sc->rx.rxotherant = 0;
1939                 }
1940
1941                 if (rxs->flag & RX_FLAG_MMIC_STRIPPED)
1942                         skb_trim(skb, skb->len - 8);
1943
1944                 spin_lock_irqsave(&sc->sc_pm_lock, flags);
1945
1946                 if ((sc->ps_flags & (PS_WAIT_FOR_BEACON |
1947                                               PS_WAIT_FOR_CAB |
1948                                               PS_WAIT_FOR_PSPOLL_DATA)) ||
1949                                                 ath9k_check_auto_sleep(sc))
1950                         ath_rx_ps(sc, skb);
1951                 spin_unlock_irqrestore(&sc->sc_pm_lock, flags);
1952
1953                 if (ah->caps.hw_caps & ATH9K_HW_CAP_ANT_DIV_COMB)
1954                         ath_ant_comb_scan(sc, &rs);
1955
1956                 ieee80211_rx(hw, skb);
1957
1958 requeue_drop_frag:
1959                 if (sc->rx.frag) {
1960                         dev_kfree_skb_any(sc->rx.frag);
1961                         sc->rx.frag = NULL;
1962                 }
1963 requeue:
1964                 if (edma) {
1965                         list_add_tail(&bf->list, &sc->rx.rxbuf);
1966                         ath_rx_edma_buf_link(sc, qtype);
1967                 } else {
1968                         list_move_tail(&bf->list, &sc->rx.rxbuf);
1969                         ath_rx_buf_link(sc, bf);
1970                         ath9k_hw_rxena(ah);
1971                 }
1972         } while (1);
1973
1974         spin_unlock_bh(&sc->rx.rxbuflock);
1975
1976         if (!(ah->imask & ATH9K_INT_RXEOL)) {
1977                 ah->imask |= (ATH9K_INT_RXEOL | ATH9K_INT_RXORN);
1978                 ath9k_hw_set_interrupts(ah, ah->imask);
1979         }
1980
1981         return 0;
1982 }