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_hw *ah = sc->sc_ah;
 209         struct ath_common *common = ath9k_hw_common(ah);
 210         struct ath_buf *bf;
 211
 212         ath_rx_remove_buffer(sc, ATH9K_RX_QUEUE_LP);
 213         ath_rx_remove_buffer(sc, ATH9K_RX_QUEUE_HP);
 214
 215         list_for_each_entry(bf, &sc->rx.rxbuf, list) {
 216                 if (bf->bf_mpdu) {
 217                         dma_unmap_single(sc->dev, bf->bf_buf_addr,
 218                                         common->rx_bufsize,
 219                                         DMA_BIDIRECTIONAL);
 220                         dev_kfree_skb_any(bf->bf_mpdu);
 221                         bf->bf_buf_addr = 0;
 222                         bf->bf_mpdu = NULL;
 223                 }
 224         }
 225
 226         INIT_LIST_HEAD(&sc->rx.rxbuf);
 227
 228         kfree(sc->rx.rx_bufptr);
 229         sc->rx.rx_bufptr = NULL;
 230 }
 231
 232 static void ath_rx_edma_init_queue(struct ath_rx_edma *rx_edma, int size)
 233 {
 234         skb_queue_head_init(&rx_edma->rx_fifo);
 235         skb_queue_head_init(&rx_edma->rx_buffers);
 236         rx_edma->rx_fifo_hwsize = size;
 237 }
 238
 239 static int ath_rx_edma_init(struct ath_softc *sc, int nbufs)
 240 {
 241         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 242         struct ath_hw *ah = sc->sc_ah;
 243         struct sk_buff *skb;
 244         struct ath_buf *bf;
 245         int error = 0, i;
 246         u32 size;
 247
 248         ath9k_hw_set_rx_bufsize(ah, common->rx_bufsize -
 249                                     ah->caps.rx_status_len);
 250
 251         ath_rx_edma_init_queue(&sc->rx.rx_edma[ATH9K_RX_QUEUE_LP],
 252                                ah->caps.rx_lp_qdepth);
 253         ath_rx_edma_init_queue(&sc->rx.rx_edma[ATH9K_RX_QUEUE_HP],
 254                                ah->caps.rx_hp_qdepth);
 255
 256         size = sizeof(struct ath_buf) * nbufs;
 257         bf = kzalloc(size, GFP_KERNEL);
 258         if (!bf)
 259                 return -ENOMEM;
 260
 261         INIT_LIST_HEAD(&sc->rx.rxbuf);
 262         sc->rx.rx_bufptr = bf;
 263
 264         for (i = 0; i < nbufs; i++, bf++) {
 265                 skb = ath_rxbuf_alloc(common, common->rx_bufsize, GFP_KERNEL);
 266                 if (!skb) {
 267                         error = -ENOMEM;
 268                         goto rx_init_fail;
 269                 }
 270
 271                 memset(skb->data, 0, common->rx_bufsize);
 272                 bf->bf_mpdu = skb;
 273
 274                 bf->bf_buf_addr = dma_map_single(sc->dev, skb->data,
 275                                                  common->rx_bufsize,
 276                                                  DMA_BIDIRECTIONAL);
 277                 if (unlikely(dma_mapping_error(sc->dev,
 278                                                 bf->bf_buf_addr))) {
 279                                 dev_kfree_skb_any(skb);
 280                                 bf->bf_mpdu = NULL;
 281                                 bf->bf_buf_addr = 0;
 282                                 ath_err(common,
 283                                         "dma_mapping_error() on RX init\n");
 284                                 error = -ENOMEM;
 285                                 goto rx_init_fail;
 286                 }
 287
 288                 list_add_tail(&bf->list, &sc->rx.rxbuf);
 289         }
 290
 291         return 0;
 292
 293 rx_init_fail:
 294         ath_rx_edma_cleanup(sc);
 295         return error;
 296 }
 297
 298 static void ath_edma_start_recv(struct ath_softc *sc)
 299 {
 300         spin_lock_bh(&sc->rx.rxbuflock);
 301
 302         ath9k_hw_rxena(sc->sc_ah);
 303
 304         ath_rx_addbuffer_edma(sc, ATH9K_RX_QUEUE_HP,
 305                               sc->rx.rx_edma[ATH9K_RX_QUEUE_HP].rx_fifo_hwsize);
 306
 307         ath_rx_addbuffer_edma(sc, ATH9K_RX_QUEUE_LP,
 308                               sc->rx.rx_edma[ATH9K_RX_QUEUE_LP].rx_fifo_hwsize);
 309
 310         ath_opmode_init(sc);
 311
 312         ath9k_hw_startpcureceive(sc->sc_ah, (sc->sc_flags & SC_OP_OFFCHANNEL));
 313
 314         spin_unlock_bh(&sc->rx.rxbuflock);
 315 }
 316
 317 static void ath_edma_stop_recv(struct ath_softc *sc)
 318 {
 319         ath_rx_remove_buffer(sc, ATH9K_RX_QUEUE_HP);
 320         ath_rx_remove_buffer(sc, ATH9K_RX_QUEUE_LP);
 321 }
 322
 323 int ath_rx_init(struct ath_softc *sc, int nbufs)
 324 {
 325         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 326         struct sk_buff *skb;
 327         struct ath_buf *bf;
 328         int error = 0;
 329
 330         spin_lock_init(&sc->sc_pcu_lock);
 331         sc->sc_flags &= ~SC_OP_RXFLUSH;
 332         spin_lock_init(&sc->rx.rxbuflock);
 333
 334         common->rx_bufsize = IEEE80211_MAX_MPDU_LEN / 2 +
 335                              sc->sc_ah->caps.rx_status_len;
 336
 337         if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) {
 338                 return ath_rx_edma_init(sc, nbufs);
 339         } else {
 340                 ath_dbg(common, ATH_DBG_CONFIG, "cachelsz %u rxbufsize %u\n",
 341                         common->cachelsz, common->rx_bufsize);
 342
 343                 /* Initialize rx descriptors */
 344
 345                 error = ath_descdma_setup(sc, &sc->rx.rxdma, &sc->rx.rxbuf,
 346                                 "rx", nbufs, 1, 0);
 347                 if (error != 0) {
 348                         ath_err(common,
 349                                 "failed to allocate rx descriptors: %d\n",
 350                                 error);
 351                         goto err;
 352                 }
 353
 354                 list_for_each_entry(bf, &sc->rx.rxbuf, list) {
 355                         skb = ath_rxbuf_alloc(common, common->rx_bufsize,
 356                                               GFP_KERNEL);
 357                         if (skb == NULL) {
 358                                 error = -ENOMEM;
 359                                 goto err;
 360                         }
 361
 362                         bf->bf_mpdu = skb;
 363                         bf->bf_buf_addr = dma_map_single(sc->dev, skb->data,
 364                                         common->rx_bufsize,
 365                                         DMA_FROM_DEVICE);
 366                         if (unlikely(dma_mapping_error(sc->dev,
 367                                                         bf->bf_buf_addr))) {
 368                                 dev_kfree_skb_any(skb);
 369                                 bf->bf_mpdu = NULL;
 370                                 bf->bf_buf_addr = 0;
 371                                 ath_err(common,
 372                                         "dma_mapping_error() on RX init\n");
 373                                 error = -ENOMEM;
 374                                 goto err;
 375                         }
 376                 }
 377                 sc->rx.rxlink = NULL;
 378         }
 379
 380 err:
 381         if (error)
 382                 ath_rx_cleanup(sc);
 383
 384         return error;
 385 }
 386
 387 void ath_rx_cleanup(struct ath_softc *sc)
 388 {
 389         struct ath_hw *ah = sc->sc_ah;
 390         struct ath_common *common = ath9k_hw_common(ah);
 391         struct sk_buff *skb;
 392         struct ath_buf *bf;
 393
 394         if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) {
 395                 ath_rx_edma_cleanup(sc);
 396                 return;
 397         } else {
 398                 list_for_each_entry(bf, &sc->rx.rxbuf, list) {
 399                         skb = bf->bf_mpdu;
 400                         if (skb) {
 401                                 dma_unmap_single(sc->dev, bf->bf_buf_addr,
 402                                                 common->rx_bufsize,
 403                                                 DMA_FROM_DEVICE);
 404                                 dev_kfree_skb(skb);
 405                                 bf->bf_buf_addr = 0;
 406                                 bf->bf_mpdu = NULL;
 407                         }
 408                 }
 409
 410                 if (sc->rx.rxdma.dd_desc_len != 0)
 411                         ath_descdma_cleanup(sc, &sc->rx.rxdma, &sc->rx.rxbuf);
 412         }
 413 }
 414
 415 /*
 416  * Calculate the receive filter according to the
 417  * operating mode and state:
 418  *
 419  * o always accept unicast, broadcast, and multicast traffic
 420  * o maintain current state of phy error reception (the hal
 421  *   may enable phy error frames for noise immunity work)
 422  * o probe request frames are accepted only when operating in
 423  *   hostap, adhoc, or monitor modes
 424  * o enable promiscuous mode according to the interface state
 425  * o accept beacons:
 426  *   - when operating in adhoc mode so the 802.11 layer creates
 427  *     node table entries for peers,
 428  *   - when operating in station mode for collecting rssi data when
 429  *     the station is otherwise quiet, or
 430  *   - when operating as a repeater so we see repeater-sta beacons
 431  *   - when scanning
 432  */
 433
 434 u32 ath_calcrxfilter(struct ath_softc *sc)
 435 {
 436         u32 rfilt;
 437
 438         rfilt = ATH9K_RX_FILTER_UCAST | ATH9K_RX_FILTER_BCAST
 439                 | ATH9K_RX_FILTER_MCAST;
 440
 441         if (sc->rx.rxfilter & FIF_PROBE_REQ)
 442                 rfilt |= ATH9K_RX_FILTER_PROBEREQ;
 443
 444         /*
 445          * Set promiscuous mode when FIF_PROMISC_IN_BSS is enabled for station
 446          * mode interface or when in monitor mode. AP mode does not need this
 447          * since it receives all in-BSS frames anyway.
 448          */
 449         if (sc->sc_ah->is_monitoring)
 450                 rfilt |= ATH9K_RX_FILTER_PROM;
 451
 452         if (sc->rx.rxfilter & FIF_CONTROL)
 453                 rfilt |= ATH9K_RX_FILTER_CONTROL;
 454
 455         if ((sc->sc_ah->opmode == NL80211_IFTYPE_STATION) &&
 456             (sc->nvifs <= 1) &&
 457             !(sc->rx.rxfilter & FIF_BCN_PRBRESP_PROMISC))
 458                 rfilt |= ATH9K_RX_FILTER_MYBEACON;
 459         else
 460                 rfilt |= ATH9K_RX_FILTER_BEACON;
 461
 462         if ((sc->sc_ah->opmode == NL80211_IFTYPE_AP) ||
 463             (sc->rx.rxfilter & FIF_PSPOLL))
 464                 rfilt |= ATH9K_RX_FILTER_PSPOLL;
 465
 466         if (conf_is_ht(&sc->hw->conf))
 467                 rfilt |= ATH9K_RX_FILTER_COMP_BAR;
 468
 469         if (sc->nvifs > 1 || (sc->rx.rxfilter & FIF_OTHER_BSS)) {
 470                 /* The following may also be needed for other older chips */
 471                 if (sc->sc_ah->hw_version.macVersion == AR_SREV_VERSION_9160)
 472                         rfilt |= ATH9K_RX_FILTER_PROM;
 473                 rfilt |= ATH9K_RX_FILTER_MCAST_BCAST_ALL;
 474         }
 475
 476         return rfilt;
 477
 478 #undef RX_FILTER_PRESERVE
 479 }
 480
 481 int ath_startrecv(struct ath_softc *sc)
 482 {
 483         struct ath_hw *ah = sc->sc_ah;
 484         struct ath_buf *bf, *tbf;
 485
 486         if (ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) {
 487                 ath_edma_start_recv(sc);
 488                 return 0;
 489         }
 490
 491         spin_lock_bh(&sc->rx.rxbuflock);
 492         if (list_empty(&sc->rx.rxbuf))
 493                 goto start_recv;
 494
 495         sc->rx.rxlink = NULL;
 496         list_for_each_entry_safe(bf, tbf, &sc->rx.rxbuf, list) {
 497                 ath_rx_buf_link(sc, bf);
 498         }
 499
 500         /* We could have deleted elements so the list may be empty now */
 501         if (list_empty(&sc->rx.rxbuf))
 502                 goto start_recv;
 503
 504         bf = list_first_entry(&sc->rx.rxbuf, struct ath_buf, list);
 505         ath9k_hw_putrxbuf(ah, bf->bf_daddr);
 506         ath9k_hw_rxena(ah);
 507
 508 start_recv:
 509         ath_opmode_init(sc);
 510         ath9k_hw_startpcureceive(ah, (sc->sc_flags & SC_OP_OFFCHANNEL));
 511
 512         spin_unlock_bh(&sc->rx.rxbuflock);
 513
 514         return 0;
 515 }
 516
 517 bool ath_stoprecv(struct ath_softc *sc)
 518 {
 519         struct ath_hw *ah = sc->sc_ah;
 520         bool stopped, reset = false;
 521
 522         spin_lock_bh(&sc->rx.rxbuflock);
 523         ath9k_hw_abortpcurecv(ah);
 524         ath9k_hw_setrxfilter(ah, 0);
 525         stopped = ath9k_hw_stopdmarecv(ah, &reset);
 526
 527         if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA)
 528                 ath_edma_stop_recv(sc);
 529         else
 530                 sc->rx.rxlink = NULL;
 531         spin_unlock_bh(&sc->rx.rxbuflock);
 532
 533         if (!(ah->ah_flags & AH_UNPLUGGED) &&
 534             unlikely(!stopped)) {
 535                 ath_err(ath9k_hw_common(sc->sc_ah),
 536                         "Could not stop RX, we could be "
 537                         "confusing the DMA engine when we start RX up\n");
 538                 ATH_DBG_WARN_ON_ONCE(!stopped);
 539         }
 540         return stopped && !reset;
 541 }
 542
 543 void ath_flushrecv(struct ath_softc *sc)
 544 {
 545         sc->sc_flags |= SC_OP_RXFLUSH;
 546         if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA)
 547                 ath_rx_tasklet(sc, 1, true);
 548         ath_rx_tasklet(sc, 1, false);
 549         sc->sc_flags &= ~SC_OP_RXFLUSH;
 550 }
 551
 552 static bool ath_beacon_dtim_pending_cab(struct sk_buff *skb)
 553 {
 554         /* Check whether the Beacon frame has DTIM indicating buffered bc/mc */
 555         struct ieee80211_mgmt *mgmt;
 556         u8 *pos, *end, id, elen;
 557         struct ieee80211_tim_ie *tim;
 558
 559         mgmt = (struct ieee80211_mgmt *)skb->data;
 560         pos = mgmt->u.beacon.variable;
 561         end = skb->data + skb->len;
 562
 563         while (pos + 2 < end) {
 564                 id = *pos++;
 565                 elen = *pos++;
 566                 if (pos + elen > end)
 567                         break;
 568
 569                 if (id == WLAN_EID_TIM) {
 570                         if (elen < sizeof(*tim))
 571                                 break;
 572                         tim = (struct ieee80211_tim_ie *) pos;
 573                         if (tim->dtim_count != 0)
 574                                 break;
 575                         return tim->bitmap_ctrl & 0x01;
 576                 }
 577
 578                 pos += elen;
 579         }
 580
 581         return false;
 582 }
 583
 584 static void ath_rx_ps_beacon(struct ath_softc *sc, struct sk_buff *skb)
 585 {
 586         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 587
 588         if (skb->len < 24 + 8 + 2 + 2)
 589                 return;
 590
 591         sc->ps_flags &= ~PS_WAIT_FOR_BEACON;
 592
 593         if (sc->ps_flags & PS_BEACON_SYNC) {
 594                 sc->ps_flags &= ~PS_BEACON_SYNC;
 595                 ath_dbg(common, ATH_DBG_PS,
 596                         "Reconfigure Beacon timers based on timestamp from the AP\n");
 597                 ath_set_beacon(sc);
 598         }
 599
 600         if (ath_beacon_dtim_pending_cab(skb)) {
 601                 /*
 602                  * Remain awake waiting for buffered broadcast/multicast
 603                  * frames. If the last broadcast/multicast frame is not
 604                  * received properly, the next beacon frame will work as
 605                  * a backup trigger for returning into NETWORK SLEEP state,
 606                  * so we are waiting for it as well.
 607                  */
 608                 ath_dbg(common, ATH_DBG_PS,
 609                         "Received DTIM beacon indicating buffered broadcast/multicast frame(s)\n");
 610                 sc->ps_flags |= PS_WAIT_FOR_CAB | PS_WAIT_FOR_BEACON;
 611                 return;
 612         }
 613
 614         if (sc->ps_flags & PS_WAIT_FOR_CAB) {
 615                 /*
 616                  * This can happen if a broadcast frame is dropped or the AP
 617                  * fails to send a frame indicating that all CAB frames have
 618                  * been delivered.
 619                  */
 620                 sc->ps_flags &= ~PS_WAIT_FOR_CAB;
 621                 ath_dbg(common, ATH_DBG_PS,
 622                         "PS wait for CAB frames timed out\n");
 623         }
 624 }
 625
 626 static void ath_rx_ps(struct ath_softc *sc, struct sk_buff *skb, bool mybeacon)
 627 {
 628         struct ieee80211_hdr *hdr;
 629         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 630
 631         hdr = (struct ieee80211_hdr *)skb->data;
 632
 633         /* Process Beacon and CAB receive in PS state */
 634         if (((sc->ps_flags & PS_WAIT_FOR_BEACON) || ath9k_check_auto_sleep(sc))
 635             && mybeacon)
 636                 ath_rx_ps_beacon(sc, skb);
 637         else if ((sc->ps_flags & PS_WAIT_FOR_CAB) &&
 638                  (ieee80211_is_data(hdr->frame_control) ||
 639                   ieee80211_is_action(hdr->frame_control)) &&
 640                  is_multicast_ether_addr(hdr->addr1) &&
 641                  !ieee80211_has_moredata(hdr->frame_control)) {
 642                 /*
 643                  * No more broadcast/multicast frames to be received at this
 644                  * point.
 645                  */
 646                 sc->ps_flags &= ~(PS_WAIT_FOR_CAB | PS_WAIT_FOR_BEACON);
 647                 ath_dbg(common, ATH_DBG_PS,
 648                         "All PS CAB frames received, back to sleep\n");
 649         } else if ((sc->ps_flags & PS_WAIT_FOR_PSPOLL_DATA) &&
 650                    !is_multicast_ether_addr(hdr->addr1) &&
 651                    !ieee80211_has_morefrags(hdr->frame_control)) {
 652                 sc->ps_flags &= ~PS_WAIT_FOR_PSPOLL_DATA;
 653                 ath_dbg(common, ATH_DBG_PS,
 654                         "Going back to sleep after having received PS-Poll data (0x%lx)\n",
 655                         sc->ps_flags & (PS_WAIT_FOR_BEACON |
 656                                         PS_WAIT_FOR_CAB |
 657                                         PS_WAIT_FOR_PSPOLL_DATA |
 658                                         PS_WAIT_FOR_TX_ACK));
 659         }
 660 }
 661
 662 static bool ath_edma_get_buffers(struct ath_softc *sc,
 663                                  enum ath9k_rx_qtype qtype)
 664 {
 665         struct ath_rx_edma *rx_edma = &sc->rx.rx_edma[qtype];
 666         struct ath_hw *ah = sc->sc_ah;
 667         struct ath_common *common = ath9k_hw_common(ah);
 668         struct sk_buff *skb;
 669         struct ath_buf *bf;
 670         int ret;
 671
 672         skb = skb_peek(&rx_edma->rx_fifo);
 673         if (!skb)
 674                 return false;
 675
 676         bf = SKB_CB_ATHBUF(skb);
 677         BUG_ON(!bf);
 678
 679         dma_sync_single_for_cpu(sc->dev, bf->bf_buf_addr,
 680                                 common->rx_bufsize, DMA_FROM_DEVICE);
 681
 682         ret = ath9k_hw_process_rxdesc_edma(ah, NULL, skb->data);
 683         if (ret == -EINPROGRESS) {
 684                 /*let device gain the buffer again*/
 685                 dma_sync_single_for_device(sc->dev, bf->bf_buf_addr,
 686                                 common->rx_bufsize, DMA_FROM_DEVICE);
 687                 return false;
 688         }
 689
 690         __skb_unlink(skb, &rx_edma->rx_fifo);
 691         if (ret == -EINVAL) {
 692                 /* corrupt descriptor, skip this one and the following one */
 693                 list_add_tail(&bf->list, &sc->rx.rxbuf);
 694                 ath_rx_edma_buf_link(sc, qtype);
 695                 skb = skb_peek(&rx_edma->rx_fifo);
 696                 if (!skb)
 697                         return true;
 698
 699                 bf = SKB_CB_ATHBUF(skb);
 700                 BUG_ON(!bf);
 701
 702                 __skb_unlink(skb, &rx_edma->rx_fifo);
 703                 list_add_tail(&bf->list, &sc->rx.rxbuf);
 704                 ath_rx_edma_buf_link(sc, qtype);
 705                 return true;
 706         }
 707         skb_queue_tail(&rx_edma->rx_buffers, skb);
 708
 709         return true;
 710 }
 711
 712 static struct ath_buf *ath_edma_get_next_rx_buf(struct ath_softc *sc,
 713                                                 struct ath_rx_status *rs,
 714                                                 enum ath9k_rx_qtype qtype)
 715 {
 716         struct ath_rx_edma *rx_edma = &sc->rx.rx_edma[qtype];
 717         struct sk_buff *skb;
 718         struct ath_buf *bf;
 719
 720         while (ath_edma_get_buffers(sc, qtype));
 721         skb = __skb_dequeue(&rx_edma->rx_buffers);
 722         if (!skb)
 723                 return NULL;
 724
 725         bf = SKB_CB_ATHBUF(skb);
 726         ath9k_hw_process_rxdesc_edma(sc->sc_ah, rs, skb->data);
 727         return bf;
 728 }
 729
 730 static struct ath_buf *ath_get_next_rx_buf(struct ath_softc *sc,
 731                                            struct ath_rx_status *rs)
 732 {
 733         struct ath_hw *ah = sc->sc_ah;
 734         struct ath_common *common = ath9k_hw_common(ah);
 735         struct ath_desc *ds;
 736         struct ath_buf *bf;
 737         int ret;
 738
 739         if (list_empty(&sc->rx.rxbuf)) {
 740                 sc->rx.rxlink = NULL;
 741                 return NULL;
 742         }
 743
 744         bf = list_first_entry(&sc->rx.rxbuf, struct ath_buf, list);
 745         ds = bf->bf_desc;
 746
 747         /*
 748          * Must provide the virtual address of the current
 749          * descriptor, the physical address, and the virtual
 750          * address of the next descriptor in the h/w chain.
 751          * This allows the HAL to look ahead to see if the
 752          * hardware is done with a descriptor by checking the
 753          * done bit in the following descriptor and the address
 754          * of the current descriptor the DMA engine is working
 755          * on.  All this is necessary because of our use of
 756          * a self-linked list to avoid rx overruns.
 757          */
 758         ret = ath9k_hw_rxprocdesc(ah, ds, rs);
 759         if (ret == -EINPROGRESS) {
 760                 struct ath_rx_status trs;
 761                 struct ath_buf *tbf;
 762                 struct ath_desc *tds;
 763
 764                 memset(&trs, 0, sizeof(trs));
 765                 if (list_is_last(&bf->list, &sc->rx.rxbuf)) {
 766                         sc->rx.rxlink = NULL;
 767                         return NULL;
 768                 }
 769
 770                 tbf = list_entry(bf->list.next, struct ath_buf, list);
 771
 772                 /*
 773                  * On some hardware the descriptor status words could
 774                  * get corrupted, including the done bit. Because of
 775                  * this, check if the next descriptor's done bit is
 776                  * set or not.
 777                  *
 778                  * If the next descriptor's done bit is set, the current
 779                  * descriptor has been corrupted. Force s/w to discard
 780                  * this descriptor and continue...
 781                  */
 782
 783                 tds = tbf->bf_desc;
 784                 ret = ath9k_hw_rxprocdesc(ah, tds, &trs);
 785                 if (ret == -EINPROGRESS)
 786                         return NULL;
 787         }
 788
 789         if (!bf->bf_mpdu)
 790                 return bf;
 791
 792         /*
 793          * Synchronize the DMA transfer with CPU before
 794          * 1. accessing the frame
 795          * 2. requeueing the same buffer to h/w
 796          */
 797         dma_sync_single_for_cpu(sc->dev, bf->bf_buf_addr,
 798                         common->rx_bufsize,
 799                         DMA_FROM_DEVICE);
 800
 801         return bf;
 802 }
 803
 804 /* Assumes you've already done the endian to CPU conversion */
 805 static bool ath9k_rx_accept(struct ath_common *common,
 806                             struct ieee80211_hdr *hdr,
 807                             struct ieee80211_rx_status *rxs,
 808                             struct ath_rx_status *rx_stats,
 809                             bool *decrypt_error)
 810 {
 811         bool is_mc, is_valid_tkip, strip_mic, mic_error;
 812         struct ath_hw *ah = common->ah;
 813         __le16 fc;
 814         u8 rx_status_len = ah->caps.rx_status_len;
 815
 816         fc = hdr->frame_control;
 817
 818         is_mc = !!is_multicast_ether_addr(hdr->addr1);
 819         is_valid_tkip = rx_stats->rs_keyix != ATH9K_RXKEYIX_INVALID &&
 820                 test_bit(rx_stats->rs_keyix, common->tkip_keymap);
 821         strip_mic = is_valid_tkip && ieee80211_is_data(fc) &&
 822                 !(rx_stats->rs_status &
 823                 (ATH9K_RXERR_DECRYPT | ATH9K_RXERR_CRC | ATH9K_RXERR_MIC));
 824
 825         if (!rx_stats->rs_datalen)
 826                 return false;
 827         /*
 828          * rs_status follows rs_datalen so if rs_datalen is too large
 829          * we can take a hint that hardware corrupted it, so ignore
 830          * those frames.
 831          */
 832         if (rx_stats->rs_datalen > (common->rx_bufsize - rx_status_len))
 833                 return false;
 834
 835         /* Only use error bits from the last fragment */
 836         if (rx_stats->rs_more)
 837                 return true;
 838
 839         mic_error = is_valid_tkip && !ieee80211_is_ctl(fc) &&
 840                 !ieee80211_has_morefrags(fc) &&
 841                 !(le16_to_cpu(hdr->seq_ctrl) & IEEE80211_SCTL_FRAG) &&
 842                 (rx_stats->rs_status & ATH9K_RXERR_MIC);
 843
 844         /*
 845          * The rx_stats->rs_status will not be set until the end of the
 846          * chained descriptors so it can be ignored if rs_more is set. The
 847          * rs_more will be false at the last element of the chained
 848          * descriptors.
 849          */
 850         if (rx_stats->rs_status != 0) {
 851                 if (rx_stats->rs_status & ATH9K_RXERR_CRC) {
 852                         rxs->flag |= RX_FLAG_FAILED_FCS_CRC;
 853                         mic_error = false;
 854                 }
 855                 if (rx_stats->rs_status & ATH9K_RXERR_PHY)
 856                         return false;
 857
 858                 if (rx_stats->rs_status & ATH9K_RXERR_DECRYPT) {
 859                         *decrypt_error = true;
 860                         mic_error = false;
 861                 }
 862
 863                 /*
 864                  * Reject error frames with the exception of
 865                  * decryption and MIC failures. For monitor mode,
 866                  * we also ignore the CRC error.
 867                  */
 868                 if (ah->is_monitoring) {
 869                         if (rx_stats->rs_status &
 870                             ~(ATH9K_RXERR_DECRYPT | ATH9K_RXERR_MIC |
 871                               ATH9K_RXERR_CRC))
 872                                 return false;
 873                 } else {
 874                         if (rx_stats->rs_status &
 875                             ~(ATH9K_RXERR_DECRYPT | ATH9K_RXERR_MIC)) {
 876                                 return false;
 877                         }
 878                 }
 879         }
 880
 881         /*
 882          * For unicast frames the MIC error bit can have false positives,
 883          * so all MIC error reports need to be validated in software.
 884          * False negatives are not common, so skip software verification
 885          * if the hardware considers the MIC valid.
 886          */
 887         if (strip_mic)
 888                 rxs->flag |= RX_FLAG_MMIC_STRIPPED;
 889         else if (is_mc && mic_error)
 890                 rxs->flag |= RX_FLAG_MMIC_ERROR;
 891
 892         return true;
 893 }
 894
 895 static int ath9k_process_rate(struct ath_common *common,
 896                               struct ieee80211_hw *hw,
 897                               struct ath_rx_status *rx_stats,
 898                               struct ieee80211_rx_status *rxs)
 899 {
 900         struct ieee80211_supported_band *sband;
 901         enum ieee80211_band band;
 902         unsigned int i = 0;
 903
 904         band = hw->conf.channel->band;
 905         sband = hw->wiphy->bands[band];
 906
 907         if (rx_stats->rs_rate & 0x80) {
 908                 /* HT rate */
 909                 rxs->flag |= RX_FLAG_HT;
 910                 if (rx_stats->rs_flags & ATH9K_RX_2040)
 911                         rxs->flag |= RX_FLAG_40MHZ;
 912                 if (rx_stats->rs_flags & ATH9K_RX_GI)
 913                         rxs->flag |= RX_FLAG_SHORT_GI;
 914                 rxs->rate_idx = rx_stats->rs_rate & 0x7f;
 915                 return 0;
 916         }
 917
 918         for (i = 0; i < sband->n_bitrates; i++) {
 919                 if (sband->bitrates[i].hw_value == rx_stats->rs_rate) {
 920                         rxs->rate_idx = i;
 921                         return 0;
 922                 }
 923                 if (sband->bitrates[i].hw_value_short == rx_stats->rs_rate) {
 924                         rxs->flag |= RX_FLAG_SHORTPRE;
 925                         rxs->rate_idx = i;
 926                         return 0;
 927                 }
 928         }
 929
 930         /*
 931          * No valid hardware bitrate found -- we should not get here
 932          * because hardware has already validated this frame as OK.
 933          */
 934         ath_dbg(common, ATH_DBG_ANY,
 935                 "unsupported hw bitrate detected 0x%02x using 1 Mbit\n",
 936                 rx_stats->rs_rate);
 937
 938         return -EINVAL;
 939 }
 940
 941 static void ath9k_process_rssi(struct ath_common *common,
 942                                struct ieee80211_hw *hw,
 943                                struct ieee80211_hdr *hdr,
 944                                struct ath_rx_status *rx_stats)
 945 {
 946         struct ath_softc *sc = hw->priv;
 947         struct ath_hw *ah = common->ah;
 948         int last_rssi;
 949
 950         if (!rx_stats->is_mybeacon ||
 951             ((ah->opmode != NL80211_IFTYPE_STATION) &&
 952              (ah->opmode != NL80211_IFTYPE_ADHOC)))
 953                 return;
 954
 955         if (rx_stats->rs_rssi != ATH9K_RSSI_BAD && !rx_stats->rs_moreaggr)
 956                 ATH_RSSI_LPF(sc->last_rssi, rx_stats->rs_rssi);
 957
 958         last_rssi = sc->last_rssi;
 959         if (likely(last_rssi != ATH_RSSI_DUMMY_MARKER))
 960                 rx_stats->rs_rssi = ATH_EP_RND(last_rssi,
 961                                               ATH_RSSI_EP_MULTIPLIER);
 962         if (rx_stats->rs_rssi < 0)
 963                 rx_stats->rs_rssi = 0;
 964
 965         /* Update Beacon RSSI, this is used by ANI. */
 966         ah->stats.avgbrssi = rx_stats->rs_rssi;
 967 }
 968
 969 /*
 970  * For Decrypt or Demic errors, we only mark packet status here and always push
 971  * up the frame up to let mac80211 handle the actual error case, be it no
 972  * decryption key or real decryption error. This let us keep statistics there.
 973  */
 974 static int ath9k_rx_skb_preprocess(struct ath_common *common,
 975                                    struct ieee80211_hw *hw,
 976                                    struct ieee80211_hdr *hdr,
 977                                    struct ath_rx_status *rx_stats,
 978                                    struct ieee80211_rx_status *rx_status,
 979                                    bool *decrypt_error)
 980 {
 981         struct ath_hw *ah = common->ah;
 982
 983         memset(rx_status, 0, sizeof(struct ieee80211_rx_status));
 984
 985         /*
 986          * everything but the rate is checked here, the rate check is done
 987          * separately to avoid doing two lookups for a rate for each frame.
 988          */
 989         if (!ath9k_rx_accept(common, hdr, rx_status, rx_stats, decrypt_error))
 990                 return -EINVAL;
 991
 992         /* Only use status info from the last fragment */
 993         if (rx_stats->rs_more)
 994                 return 0;
 995
 996         ath9k_process_rssi(common, hw, hdr, rx_stats);
 997
 998         if (ath9k_process_rate(common, hw, rx_stats, rx_status))
 999                 return -EINVAL;
1000
1001         rx_status->band = hw->conf.channel->band;
1002         rx_status->freq = hw->conf.channel->center_freq;
1003         rx_status->signal = ah->noise + rx_stats->rs_rssi;
1004         rx_status->antenna = rx_stats->rs_antenna;
1005         rx_status->flag |= RX_FLAG_MACTIME_MPDU;
1006
1007         return 0;
1008 }
1009
1010 static void ath9k_rx_skb_postprocess(struct ath_common *common,
1011                                      struct sk_buff *skb,
1012                                      struct ath_rx_status *rx_stats,
1013                                      struct ieee80211_rx_status *rxs,
1014                                      bool decrypt_error)
1015 {
1016         struct ath_hw *ah = common->ah;
1017         struct ieee80211_hdr *hdr;
1018         int hdrlen, padpos, padsize;
1019         u8 keyix;
1020         __le16 fc;
1021
1022         /* see if any padding is done by the hw and remove it */
1023         hdr = (struct ieee80211_hdr *) skb->data;
1024         hdrlen = ieee80211_get_hdrlen_from_skb(skb);
1025         fc = hdr->frame_control;
1026         padpos = ath9k_cmn_padpos(hdr->frame_control);
1027
1028         /* The MAC header is padded to have 32-bit boundary if the
1029          * packet payload is non-zero. The general calculation for
1030          * padsize would take into account odd header lengths:
1031          * padsize = (4 - padpos % 4) % 4; However, since only
1032          * even-length headers are used, padding can only be 0 or 2
1033          * bytes and we can optimize this a bit. In addition, we must
1034          * not try to remove padding from short control frames that do
1035          * not have payload. */
1036         padsize = padpos & 3;
1037         if (padsize && skb->len>=padpos+padsize+FCS_LEN) {
1038                 memmove(skb->data + padsize, skb->data, padpos);
1039                 skb_pull(skb, padsize);
1040         }
1041
1042         keyix = rx_stats->rs_keyix;
1043
1044         if (!(keyix == ATH9K_RXKEYIX_INVALID) && !decrypt_error &&
1045             ieee80211_has_protected(fc)) {
1046                 rxs->flag |= RX_FLAG_DECRYPTED;
1047         } else if (ieee80211_has_protected(fc)
1048                    && !decrypt_error && skb->len >= hdrlen + 4) {
1049                 keyix = skb->data[hdrlen + 3] >> 6;
1050
1051                 if (test_bit(keyix, common->keymap))
1052                         rxs->flag |= RX_FLAG_DECRYPTED;
1053         }
1054         if (ah->sw_mgmt_crypto &&
1055             (rxs->flag & RX_FLAG_DECRYPTED) &&
1056             ieee80211_is_mgmt(fc))
1057                 /* Use software decrypt for management frames. */
1058                 rxs->flag &= ~RX_FLAG_DECRYPTED;
1059 }
1060
1061 static void ath_lnaconf_alt_good_scan(struct ath_ant_comb *antcomb,
1062                                       struct ath_hw_antcomb_conf ant_conf,
1063                                       int main_rssi_avg)
1064 {
1065         antcomb->quick_scan_cnt = 0;
1066
1067         if (ant_conf.main_lna_conf == ATH_ANT_DIV_COMB_LNA2)
1068                 antcomb->rssi_lna2 = main_rssi_avg;
1069         else if (ant_conf.main_lna_conf == ATH_ANT_DIV_COMB_LNA1)
1070                 antcomb->rssi_lna1 = main_rssi_avg;
1071
1072         switch ((ant_conf.main_lna_conf << 4) | ant_conf.alt_lna_conf) {
1073         case 0x10: /* LNA2 A-B */
1074                 antcomb->main_conf = ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
1075                 antcomb->first_quick_scan_conf =
1076                         ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
1077                 antcomb->second_quick_scan_conf = ATH_ANT_DIV_COMB_LNA1;
1078                 break;
1079         case 0x20: /* LNA1 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_LNA2;
1084                 break;
1085         case 0x21: /* LNA1 LNA2 */
1086                 antcomb->main_conf = ATH_ANT_DIV_COMB_LNA2;
1087                 antcomb->first_quick_scan_conf =
1088                         ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
1089                 antcomb->second_quick_scan_conf =
1090                         ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
1091                 break;
1092         case 0x12: /* LNA2 LNA1 */
1093                 antcomb->main_conf = ATH_ANT_DIV_COMB_LNA1;
1094                 antcomb->first_quick_scan_conf =
1095                         ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
1096                 antcomb->second_quick_scan_conf =
1097                         ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
1098                 break;
1099         case 0x13: /* LNA2 A+B */
1100                 antcomb->main_conf = ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
1101                 antcomb->first_quick_scan_conf =
1102                         ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
1103                 antcomb->second_quick_scan_conf = ATH_ANT_DIV_COMB_LNA1;
1104                 break;
1105         case 0x23: /* LNA1 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_LNA2;
1110                 break;
1111         default:
1112                 break;
1113         }
1114 }
1115
1116 static void ath_select_ant_div_from_quick_scan(struct ath_ant_comb *antcomb,
1117                                 struct ath_hw_antcomb_conf *div_ant_conf,
1118                                 int main_rssi_avg, int alt_rssi_avg,
1119                                 int alt_ratio)
1120 {
1121         /* alt_good */
1122         switch (antcomb->quick_scan_cnt) {
1123         case 0:
1124                 /* set alt to main, and alt to first conf */
1125                 div_ant_conf->main_lna_conf = antcomb->main_conf;
1126                 div_ant_conf->alt_lna_conf = antcomb->first_quick_scan_conf;
1127                 break;
1128         case 1:
1129                 /* set alt to main, and alt to first conf */
1130                 div_ant_conf->main_lna_conf = antcomb->main_conf;
1131                 div_ant_conf->alt_lna_conf = antcomb->second_quick_scan_conf;
1132                 antcomb->rssi_first = main_rssi_avg;
1133                 antcomb->rssi_second = alt_rssi_avg;
1134
1135                 if (antcomb->main_conf == ATH_ANT_DIV_COMB_LNA1) {
1136                         /* main is LNA1 */
1137                         if (ath_is_alt_ant_ratio_better(alt_ratio,
1138                                                 ATH_ANT_DIV_COMB_LNA1_DELTA_HI,
1139                                                 ATH_ANT_DIV_COMB_LNA1_DELTA_LOW,
1140                                                 main_rssi_avg, alt_rssi_avg,
1141                                                 antcomb->total_pkt_count))
1142                                 antcomb->first_ratio = true;
1143                         else
1144                                 antcomb->first_ratio = false;
1145                 } else if (antcomb->main_conf == ATH_ANT_DIV_COMB_LNA2) {
1146                         if (ath_is_alt_ant_ratio_better(alt_ratio,
1147                                                 ATH_ANT_DIV_COMB_LNA1_DELTA_MID,
1148                                                 ATH_ANT_DIV_COMB_LNA1_DELTA_LOW,
1149                                                 main_rssi_avg, alt_rssi_avg,
1150                                                 antcomb->total_pkt_count))
1151                                 antcomb->first_ratio = true;
1152                         else
1153                                 antcomb->first_ratio = false;
1154                 } else {
1155                         if ((((alt_ratio >= ATH_ANT_DIV_COMB_ALT_ANT_RATIO2) &&
1156                             (alt_rssi_avg > main_rssi_avg +
1157                             ATH_ANT_DIV_COMB_LNA1_DELTA_HI)) ||
1158                             (alt_rssi_avg > main_rssi_avg)) &&
1159                             (antcomb->total_pkt_count > 50))
1160                                 antcomb->first_ratio = true;
1161                         else
1162                                 antcomb->first_ratio = false;
1163                 }
1164                 break;
1165         case 2:
1166                 antcomb->alt_good = false;
1167                 antcomb->scan_not_start = false;
1168                 antcomb->scan = false;
1169                 antcomb->rssi_first = main_rssi_avg;
1170                 antcomb->rssi_third = alt_rssi_avg;
1171
1172                 if (antcomb->second_quick_scan_conf == ATH_ANT_DIV_COMB_LNA1)
1173                         antcomb->rssi_lna1 = alt_rssi_avg;
1174                 else if (antcomb->second_quick_scan_conf ==
1175                          ATH_ANT_DIV_COMB_LNA2)
1176                         antcomb->rssi_lna2 = alt_rssi_avg;
1177                 else if (antcomb->second_quick_scan_conf ==
1178                          ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2) {
1179                         if (antcomb->main_conf == ATH_ANT_DIV_COMB_LNA2)
1180                                 antcomb->rssi_lna2 = main_rssi_avg;
1181                         else if (antcomb->main_conf == ATH_ANT_DIV_COMB_LNA1)
1182                                 antcomb->rssi_lna1 = main_rssi_avg;
1183                 }
1184
1185                 if (antcomb->rssi_lna2 > antcomb->rssi_lna1 +
1186                     ATH_ANT_DIV_COMB_LNA1_LNA2_SWITCH_DELTA)
1187                         div_ant_conf->main_lna_conf = ATH_ANT_DIV_COMB_LNA2;
1188                 else
1189                         div_ant_conf->main_lna_conf = ATH_ANT_DIV_COMB_LNA1;
1190
1191                 if (antcomb->main_conf == ATH_ANT_DIV_COMB_LNA1) {
1192                         if (ath_is_alt_ant_ratio_better(alt_ratio,
1193                                                 ATH_ANT_DIV_COMB_LNA1_DELTA_HI,
1194                                                 ATH_ANT_DIV_COMB_LNA1_DELTA_LOW,
1195                                                 main_rssi_avg, alt_rssi_avg,
1196                                                 antcomb->total_pkt_count))
1197                                 antcomb->second_ratio = true;
1198                         else
1199                                 antcomb->second_ratio = false;
1200                 } else if (antcomb->main_conf == ATH_ANT_DIV_COMB_LNA2) {
1201                         if (ath_is_alt_ant_ratio_better(alt_ratio,
1202                                                 ATH_ANT_DIV_COMB_LNA1_DELTA_MID,
1203                                                 ATH_ANT_DIV_COMB_LNA1_DELTA_LOW,
1204                                                 main_rssi_avg, alt_rssi_avg,
1205                                                 antcomb->total_pkt_count))
1206                                 antcomb->second_ratio = true;
1207                         else
1208                                 antcomb->second_ratio = false;
1209                 } else {
1210                         if ((((alt_ratio >= ATH_ANT_DIV_COMB_ALT_ANT_RATIO2) &&
1211                             (alt_rssi_avg > main_rssi_avg +
1212                             ATH_ANT_DIV_COMB_LNA1_DELTA_HI)) ||
1213                             (alt_rssi_avg > main_rssi_avg)) &&
1214                             (antcomb->total_pkt_count > 50))
1215                                 antcomb->second_ratio = true;
1216                         else
1217                                 antcomb->second_ratio = false;
1218                 }
1219
1220                 /* set alt to the conf with maximun ratio */
1221                 if (antcomb->first_ratio && antcomb->second_ratio) {
1222                         if (antcomb->rssi_second > antcomb->rssi_third) {
1223                                 /* first alt*/
1224                                 if ((antcomb->first_quick_scan_conf ==
1225                                     ATH_ANT_DIV_COMB_LNA1) ||
1226                                     (antcomb->first_quick_scan_conf ==
1227                                     ATH_ANT_DIV_COMB_LNA2))
1228                                         /* Set alt LNA1 or LNA2*/
1229                                         if (div_ant_conf->main_lna_conf ==
1230                                             ATH_ANT_DIV_COMB_LNA2)
1231                                                 div_ant_conf->alt_lna_conf =
1232                                                         ATH_ANT_DIV_COMB_LNA1;
1233                                         else
1234                                                 div_ant_conf->alt_lna_conf =
1235                                                         ATH_ANT_DIV_COMB_LNA2;
1236                                 else
1237                                         /* Set alt to A+B or A-B */
1238                                         div_ant_conf->alt_lna_conf =
1239                                                 antcomb->first_quick_scan_conf;
1240                         } else if ((antcomb->second_quick_scan_conf ==
1241                                    ATH_ANT_DIV_COMB_LNA1) ||
1242                                    (antcomb->second_quick_scan_conf ==
1243                                    ATH_ANT_DIV_COMB_LNA2)) {
1244                                 /* Set alt LNA1 or LNA2 */
1245                                 if (div_ant_conf->main_lna_conf ==
1246                                     ATH_ANT_DIV_COMB_LNA2)
1247                                         div_ant_conf->alt_lna_conf =
1248                                                 ATH_ANT_DIV_COMB_LNA1;
1249                                 else
1250                                         div_ant_conf->alt_lna_conf =
1251                                                 ATH_ANT_DIV_COMB_LNA2;
1252                         } else {
1253                                 /* Set alt to A+B or A-B */
1254                                 div_ant_conf->alt_lna_conf =
1255                                         antcomb->second_quick_scan_conf;
1256                         }
1257                 } else if (antcomb->first_ratio) {
1258                         /* first alt */
1259                         if ((antcomb->first_quick_scan_conf ==
1260                             ATH_ANT_DIV_COMB_LNA1) ||
1261                             (antcomb->first_quick_scan_conf ==
1262                             ATH_ANT_DIV_COMB_LNA2))
1263                                         /* Set alt LNA1 or LNA2 */
1264                                 if (div_ant_conf->main_lna_conf ==
1265                                     ATH_ANT_DIV_COMB_LNA2)
1266                                         div_ant_conf->alt_lna_conf =
1267                                                         ATH_ANT_DIV_COMB_LNA1;
1268                                 else
1269                                         div_ant_conf->alt_lna_conf =
1270                                                         ATH_ANT_DIV_COMB_LNA2;
1271                         else
1272                                 /* Set alt to A+B or A-B */
1273                                 div_ant_conf->alt_lna_conf =
1274                                                 antcomb->first_quick_scan_conf;
1275                 } else if (antcomb->second_ratio) {
1276                                 /* second alt */
1277                         if ((antcomb->second_quick_scan_conf ==
1278                             ATH_ANT_DIV_COMB_LNA1) ||
1279                             (antcomb->second_quick_scan_conf ==
1280                             ATH_ANT_DIV_COMB_LNA2))
1281                                 /* Set alt LNA1 or LNA2 */
1282                                 if (div_ant_conf->main_lna_conf ==
1283                                     ATH_ANT_DIV_COMB_LNA2)
1284                                         div_ant_conf->alt_lna_conf =
1285                                                 ATH_ANT_DIV_COMB_LNA1;
1286                                 else
1287                                         div_ant_conf->alt_lna_conf =
1288                                                 ATH_ANT_DIV_COMB_LNA2;
1289                         else
1290                                 /* Set alt to A+B or A-B */
1291                                 div_ant_conf->alt_lna_conf =
1292                                                 antcomb->second_quick_scan_conf;
1293                 } else {
1294                         /* main is largest */
1295                         if ((antcomb->main_conf == ATH_ANT_DIV_COMB_LNA1) ||
1296                             (antcomb->main_conf == ATH_ANT_DIV_COMB_LNA2))
1297                                 /* Set alt LNA1 or LNA2 */
1298                                 if (div_ant_conf->main_lna_conf ==
1299                                     ATH_ANT_DIV_COMB_LNA2)
1300                                         div_ant_conf->alt_lna_conf =
1301                                                         ATH_ANT_DIV_COMB_LNA1;
1302                                 else
1303                                         div_ant_conf->alt_lna_conf =
1304                                                         ATH_ANT_DIV_COMB_LNA2;
1305                         else
1306                                 /* Set alt to A+B or A-B */
1307                                 div_ant_conf->alt_lna_conf = antcomb->main_conf;
1308                 }
1309                 break;
1310         default:
1311                 break;
1312         }
1313 }
1314
1315 static void ath_ant_div_conf_fast_divbias(struct ath_hw_antcomb_conf *ant_conf,
1316                 struct ath_ant_comb *antcomb, int alt_ratio)
1317 {
1318         if (ant_conf->div_group == 0) {
1319                 /* Adjust the fast_div_bias based on main and alt lna conf */
1320                 switch ((ant_conf->main_lna_conf << 4) |
1321                                 ant_conf->alt_lna_conf) {
1322                 case 0x01: /* A-B LNA2 */
1323                         ant_conf->fast_div_bias = 0x3b;
1324                         break;
1325                 case 0x02: /* A-B LNA1 */
1326                         ant_conf->fast_div_bias = 0x3d;
1327                         break;
1328                 case 0x03: /* A-B A+B */
1329                         ant_conf->fast_div_bias = 0x1;
1330                         break;
1331                 case 0x10: /* LNA2 A-B */
1332                         ant_conf->fast_div_bias = 0x7;
1333                         break;
1334                 case 0x12: /* LNA2 LNA1 */
1335                         ant_conf->fast_div_bias = 0x2;
1336                         break;
1337                 case 0x13: /* LNA2 A+B */
1338                         ant_conf->fast_div_bias = 0x7;
1339                         break;
1340                 case 0x20: /* LNA1 A-B */
1341                         ant_conf->fast_div_bias = 0x6;
1342                         break;
1343                 case 0x21: /* LNA1 LNA2 */
1344                         ant_conf->fast_div_bias = 0x0;
1345                         break;
1346                 case 0x23: /* LNA1 A+B */
1347                         ant_conf->fast_div_bias = 0x6;
1348                         break;
1349                 case 0x30: /* A+B A-B */
1350                         ant_conf->fast_div_bias = 0x1;
1351                         break;
1352                 case 0x31: /* A+B LNA2 */
1353                         ant_conf->fast_div_bias = 0x3b;
1354                         break;
1355                 case 0x32: /* A+B LNA1 */
1356                         ant_conf->fast_div_bias = 0x3d;
1357                         break;
1358                 default:
1359                         break;
1360                 }
1361         } else if (ant_conf->div_group == 1) {
1362                 /* Adjust the fast_div_bias based on main and alt_lna_conf */
1363                 switch ((ant_conf->main_lna_conf << 4) |
1364                         ant_conf->alt_lna_conf) {
1365                 case 0x01: /* A-B LNA2 */
1366                         ant_conf->fast_div_bias = 0x1;
1367                         ant_conf->main_gaintb = 0;
1368                         ant_conf->alt_gaintb = 0;
1369                         break;
1370                 case 0x02: /* A-B LNA1 */
1371                         ant_conf->fast_div_bias = 0x1;
1372                         ant_conf->main_gaintb = 0;
1373                         ant_conf->alt_gaintb = 0;
1374                         break;
1375                 case 0x03: /* A-B A+B */
1376                         ant_conf->fast_div_bias = 0x1;
1377                         ant_conf->main_gaintb = 0;
1378                         ant_conf->alt_gaintb = 0;
1379                         break;
1380                 case 0x10: /* LNA2 A-B */
1381                         if (!(antcomb->scan) &&
1382                             (alt_ratio > ATH_ANT_DIV_COMB_ALT_ANT_RATIO))
1383                                 ant_conf->fast_div_bias = 0x3f;
1384                         else
1385                                 ant_conf->fast_div_bias = 0x1;
1386                         ant_conf->main_gaintb = 0;
1387                         ant_conf->alt_gaintb = 0;
1388                         break;
1389                 case 0x12: /* LNA2 LNA1 */
1390                         ant_conf->fast_div_bias = 0x1;
1391                         ant_conf->main_gaintb = 0;
1392                         ant_conf->alt_gaintb = 0;
1393                         break;
1394                 case 0x13: /* LNA2 A+B */
1395                         if (!(antcomb->scan) &&
1396                             (alt_ratio > ATH_ANT_DIV_COMB_ALT_ANT_RATIO))
1397                                 ant_conf->fast_div_bias = 0x3f;
1398                         else
1399                                 ant_conf->fast_div_bias = 0x1;
1400                         ant_conf->main_gaintb = 0;
1401                         ant_conf->alt_gaintb = 0;
1402                         break;
1403                 case 0x20: /* LNA1 A-B */
1404                         if (!(antcomb->scan) &&
1405                             (alt_ratio > ATH_ANT_DIV_COMB_ALT_ANT_RATIO))
1406                                 ant_conf->fast_div_bias = 0x3f;
1407                         else
1408                                 ant_conf->fast_div_bias = 0x1;
1409                         ant_conf->main_gaintb = 0;
1410                         ant_conf->alt_gaintb = 0;
1411                         break;
1412                 case 0x21: /* LNA1 LNA2 */
1413                         ant_conf->fast_div_bias = 0x1;
1414                         ant_conf->main_gaintb = 0;
1415                         ant_conf->alt_gaintb = 0;
1416                         break;
1417                 case 0x23: /* LNA1 A+B */
1418                         if (!(antcomb->scan) &&
1419                             (alt_ratio > ATH_ANT_DIV_COMB_ALT_ANT_RATIO))
1420                                 ant_conf->fast_div_bias = 0x3f;
1421                         else
1422                                 ant_conf->fast_div_bias = 0x1;
1423                         ant_conf->main_gaintb = 0;
1424                         ant_conf->alt_gaintb = 0;
1425                         break;
1426                 case 0x30: /* A+B A-B */
1427                         ant_conf->fast_div_bias = 0x1;
1428                         ant_conf->main_gaintb = 0;
1429                         ant_conf->alt_gaintb = 0;
1430                         break;
1431                 case 0x31: /* A+B LNA2 */
1432                         ant_conf->fast_div_bias = 0x1;
1433                         ant_conf->main_gaintb = 0;
1434                         ant_conf->alt_gaintb = 0;
1435                         break;
1436                 case 0x32: /* A+B LNA1 */
1437                         ant_conf->fast_div_bias = 0x1;
1438                         ant_conf->main_gaintb = 0;
1439                         ant_conf->alt_gaintb = 0;
1440                         break;
1441                 default:
1442                         break;
1443                 }
1444         } else if (ant_conf->div_group == 2) {
1445                 /* Adjust the fast_div_bias based on main and alt_lna_conf */
1446                 switch ((ant_conf->main_lna_conf << 4) |
1447                                 ant_conf->alt_lna_conf) {
1448                 case 0x01: /* A-B LNA2 */
1449                         ant_conf->fast_div_bias = 0x1;
1450                         ant_conf->main_gaintb = 0;
1451                         ant_conf->alt_gaintb = 0;
1452                         break;
1453                 case 0x02: /* A-B LNA1 */
1454                         ant_conf->fast_div_bias = 0x1;
1455                         ant_conf->main_gaintb = 0;
1456                         ant_conf->alt_gaintb = 0;
1457                         break;
1458                 case 0x03: /* A-B A+B */
1459                         ant_conf->fast_div_bias = 0x1;
1460                         ant_conf->main_gaintb = 0;
1461                         ant_conf->alt_gaintb = 0;
1462                         break;
1463                 case 0x10: /* LNA2 A-B */
1464                         if (!(antcomb->scan) &&
1465                                 (alt_ratio > ATH_ANT_DIV_COMB_ALT_ANT_RATIO))
1466                                 ant_conf->fast_div_bias = 0x1;
1467                         else
1468                                 ant_conf->fast_div_bias = 0x2;
1469                         ant_conf->main_gaintb = 0;
1470                         ant_conf->alt_gaintb = 0;
1471                         break;
1472                 case 0x12: /* LNA2 LNA1 */
1473                         ant_conf->fast_div_bias = 0x1;
1474                         ant_conf->main_gaintb = 0;
1475                         ant_conf->alt_gaintb = 0;
1476                         break;
1477                 case 0x13: /* LNA2 A+B */
1478                         if (!(antcomb->scan) &&
1479                                 (alt_ratio > ATH_ANT_DIV_COMB_ALT_ANT_RATIO))
1480                                 ant_conf->fast_div_bias = 0x1;
1481                         else
1482                                 ant_conf->fast_div_bias = 0x2;
1483                         ant_conf->main_gaintb = 0;
1484                         ant_conf->alt_gaintb = 0;
1485                         break;
1486                 case 0x20: /* LNA1 A-B */
1487                         if (!(antcomb->scan) &&
1488                                 (alt_ratio > ATH_ANT_DIV_COMB_ALT_ANT_RATIO))
1489                                 ant_conf->fast_div_bias = 0x1;
1490                         else
1491                                 ant_conf->fast_div_bias = 0x2;
1492                         ant_conf->main_gaintb = 0;
1493                         ant_conf->alt_gaintb = 0;
1494                         break;
1495                 case 0x21: /* LNA1 LNA2 */
1496                         ant_conf->fast_div_bias = 0x1;
1497                         ant_conf->main_gaintb = 0;
1498                         ant_conf->alt_gaintb = 0;
1499                         break;
1500                 case 0x23: /* LNA1 A+B */
1501                         if (!(antcomb->scan) &&
1502                                 (alt_ratio > ATH_ANT_DIV_COMB_ALT_ANT_RATIO))
1503                                 ant_conf->fast_div_bias = 0x1;
1504                         else
1505                                 ant_conf->fast_div_bias = 0x2;
1506                         ant_conf->main_gaintb = 0;
1507                         ant_conf->alt_gaintb = 0;
1508                         break;
1509                 case 0x30: /* A+B A-B */
1510                         ant_conf->fast_div_bias = 0x1;
1511                         ant_conf->main_gaintb = 0;
1512                         ant_conf->alt_gaintb = 0;
1513                         break;
1514                 case 0x31: /* A+B LNA2 */
1515                         ant_conf->fast_div_bias = 0x1;
1516                         ant_conf->main_gaintb = 0;
1517                         ant_conf->alt_gaintb = 0;
1518                         break;
1519                 case 0x32: /* A+B LNA1 */
1520                         ant_conf->fast_div_bias = 0x1;
1521                         ant_conf->main_gaintb = 0;
1522                         ant_conf->alt_gaintb = 0;
1523                         break;
1524                 default:
1525                         break;
1526                 }
1527         }
1528 }
1529
1530 /* Antenna diversity and combining */
1531 static void ath_ant_comb_scan(struct ath_softc *sc, struct ath_rx_status *rs)
1532 {
1533         struct ath_hw_antcomb_conf div_ant_conf;
1534         struct ath_ant_comb *antcomb = &sc->ant_comb;
1535         int alt_ratio = 0, alt_rssi_avg = 0, main_rssi_avg = 0, curr_alt_set;
1536         int curr_main_set;
1537         int main_rssi = rs->rs_rssi_ctl0;
1538         int alt_rssi = rs->rs_rssi_ctl1;
1539         int rx_ant_conf,  main_ant_conf;
1540         bool short_scan = false;
1541
1542         rx_ant_conf = (rs->rs_rssi_ctl2 >> ATH_ANT_RX_CURRENT_SHIFT) &
1543                        ATH_ANT_RX_MASK;
1544         main_ant_conf = (rs->rs_rssi_ctl2 >> ATH_ANT_RX_MAIN_SHIFT) &
1545                          ATH_ANT_RX_MASK;
1546
1547         /* Record packet only when both main_rssi and  alt_rssi is positive */
1548         if (main_rssi > 0 && alt_rssi > 0) {
1549                 antcomb->total_pkt_count++;
1550                 antcomb->main_total_rssi += main_rssi;
1551                 antcomb->alt_total_rssi  += alt_rssi;
1552                 if (main_ant_conf == rx_ant_conf)
1553                         antcomb->main_recv_cnt++;
1554                 else
1555                         antcomb->alt_recv_cnt++;
1556         }
1557
1558         /* Short scan check */
1559         if (antcomb->scan && antcomb->alt_good) {
1560                 if (time_after(jiffies, antcomb->scan_start_time +
1561                     msecs_to_jiffies(ATH_ANT_DIV_COMB_SHORT_SCAN_INTR)))
1562                         short_scan = true;
1563                 else
1564                         if (antcomb->total_pkt_count ==
1565                             ATH_ANT_DIV_COMB_SHORT_SCAN_PKTCOUNT) {
1566                                 alt_ratio = ((antcomb->alt_recv_cnt * 100) /
1567                                             antcomb->total_pkt_count);
1568                                 if (alt_ratio < ATH_ANT_DIV_COMB_ALT_ANT_RATIO)
1569                                         short_scan = true;
1570                         }
1571         }
1572
1573         if (((antcomb->total_pkt_count < ATH_ANT_DIV_COMB_MAX_PKTCOUNT) ||
1574             rs->rs_moreaggr) && !short_scan)
1575                 return;
1576
1577         if (antcomb->total_pkt_count) {
1578                 alt_ratio = ((antcomb->alt_recv_cnt * 100) /
1579                              antcomb->total_pkt_count);
1580                 main_rssi_avg = (antcomb->main_total_rssi /
1581                                  antcomb->total_pkt_count);
1582                 alt_rssi_avg = (antcomb->alt_total_rssi /
1583                                  antcomb->total_pkt_count);
1584         }
1585
1586
1587         ath9k_hw_antdiv_comb_conf_get(sc->sc_ah, &div_ant_conf);
1588         curr_alt_set = div_ant_conf.alt_lna_conf;
1589         curr_main_set = div_ant_conf.main_lna_conf;
1590
1591         antcomb->count++;
1592
1593         if (antcomb->count == ATH_ANT_DIV_COMB_MAX_COUNT) {
1594                 if (alt_ratio > ATH_ANT_DIV_COMB_ALT_ANT_RATIO) {
1595                         ath_lnaconf_alt_good_scan(antcomb, div_ant_conf,
1596                                                   main_rssi_avg);
1597                         antcomb->alt_good = true;
1598                 } else {
1599                         antcomb->alt_good = false;
1600                 }
1601
1602                 antcomb->count = 0;
1603                 antcomb->scan = true;
1604                 antcomb->scan_not_start = true;
1605         }
1606
1607         if (!antcomb->scan) {
1608                 if (ath_ant_div_comb_alt_check(div_ant_conf.div_group,
1609                                         alt_ratio, curr_main_set, curr_alt_set,
1610                                         alt_rssi_avg, main_rssi_avg)) {
1611                         if (curr_alt_set == ATH_ANT_DIV_COMB_LNA2) {
1612                                 /* Switch main and alt LNA */
1613                                 div_ant_conf.main_lna_conf =
1614                                                 ATH_ANT_DIV_COMB_LNA2;
1615                                 div_ant_conf.alt_lna_conf  =
1616                                                 ATH_ANT_DIV_COMB_LNA1;
1617                         } else if (curr_alt_set == ATH_ANT_DIV_COMB_LNA1) {
1618                                 div_ant_conf.main_lna_conf =
1619                                                 ATH_ANT_DIV_COMB_LNA1;
1620                                 div_ant_conf.alt_lna_conf  =
1621                                                 ATH_ANT_DIV_COMB_LNA2;
1622                         }
1623
1624                         goto div_comb_done;
1625                 } else if ((curr_alt_set != ATH_ANT_DIV_COMB_LNA1) &&
1626                            (curr_alt_set != ATH_ANT_DIV_COMB_LNA2)) {
1627                         /* Set alt to another LNA */
1628                         if (curr_main_set == ATH_ANT_DIV_COMB_LNA2)
1629                                 div_ant_conf.alt_lna_conf =
1630                                                 ATH_ANT_DIV_COMB_LNA1;
1631                         else if (curr_main_set == ATH_ANT_DIV_COMB_LNA1)
1632                                 div_ant_conf.alt_lna_conf =
1633                                                 ATH_ANT_DIV_COMB_LNA2;
1634
1635                         goto div_comb_done;
1636                 }
1637
1638                 if ((alt_rssi_avg < (main_rssi_avg +
1639                                                 div_ant_conf.lna1_lna2_delta)))
1640                         goto div_comb_done;
1641         }
1642
1643         if (!antcomb->scan_not_start) {
1644                 switch (curr_alt_set) {
1645                 case ATH_ANT_DIV_COMB_LNA2:
1646                         antcomb->rssi_lna2 = alt_rssi_avg;
1647                         antcomb->rssi_lna1 = main_rssi_avg;
1648                         antcomb->scan = true;
1649                         /* set to A+B */
1650                         div_ant_conf.main_lna_conf =
1651                                 ATH_ANT_DIV_COMB_LNA1;
1652                         div_ant_conf.alt_lna_conf  =
1653                                 ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
1654                         break;
1655                 case ATH_ANT_DIV_COMB_LNA1:
1656                         antcomb->rssi_lna1 = alt_rssi_avg;
1657                         antcomb->rssi_lna2 = main_rssi_avg;
1658                         antcomb->scan = true;
1659                         /* set to A+B */
1660                         div_ant_conf.main_lna_conf = ATH_ANT_DIV_COMB_LNA2;
1661                         div_ant_conf.alt_lna_conf  =
1662                                 ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
1663                         break;
1664                 case ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2:
1665                         antcomb->rssi_add = alt_rssi_avg;
1666                         antcomb->scan = true;
1667                         /* set to A-B */
1668                         div_ant_conf.alt_lna_conf =
1669                                 ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
1670                         break;
1671                 case ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2:
1672                         antcomb->rssi_sub = alt_rssi_avg;
1673                         antcomb->scan = false;
1674                         if (antcomb->rssi_lna2 >
1675                             (antcomb->rssi_lna1 +
1676                             ATH_ANT_DIV_COMB_LNA1_LNA2_SWITCH_DELTA)) {
1677                                 /* use LNA2 as main LNA */
1678                                 if ((antcomb->rssi_add > antcomb->rssi_lna1) &&
1679                                     (antcomb->rssi_add > antcomb->rssi_sub)) {
1680                                         /* set to A+B */
1681                                         div_ant_conf.main_lna_conf =
1682                                                 ATH_ANT_DIV_COMB_LNA2;
1683                                         div_ant_conf.alt_lna_conf  =
1684                                                 ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
1685                                 } else if (antcomb->rssi_sub >
1686                                            antcomb->rssi_lna1) {
1687                                         /* set to A-B */
1688                                         div_ant_conf.main_lna_conf =
1689                                                 ATH_ANT_DIV_COMB_LNA2;
1690                                         div_ant_conf.alt_lna_conf =
1691                                                 ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
1692                                 } else {
1693                                         /* set to LNA1 */
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;
1698                                 }
1699                         } else {
1700                                 /* use LNA1 as main LNA */
1701                                 if ((antcomb->rssi_add > antcomb->rssi_lna2) &&
1702                                     (antcomb->rssi_add > antcomb->rssi_sub)) {
1703                                         /* set to A+B */
1704                                         div_ant_conf.main_lna_conf =
1705                                                 ATH_ANT_DIV_COMB_LNA1;
1706                                         div_ant_conf.alt_lna_conf  =
1707                                                 ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
1708                                 } else if (antcomb->rssi_sub >
1709                                            antcomb->rssi_lna1) {
1710                                         /* set to A-B */
1711                                         div_ant_conf.main_lna_conf =
1712                                                 ATH_ANT_DIV_COMB_LNA1;
1713                                         div_ant_conf.alt_lna_conf =
1714                                                 ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
1715                                 } else {
1716                                         /* set to LNA2 */
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_LNA2;
1721                                 }
1722                         }
1723                         break;
1724                 default:
1725                         break;
1726                 }
1727         } else {
1728                 if (!antcomb->alt_good) {
1729                         antcomb->scan_not_start = false;
1730                         /* Set alt to another LNA */
1731                         if (curr_main_set == ATH_ANT_DIV_COMB_LNA2) {
1732                                 div_ant_conf.main_lna_conf =
1733                                                 ATH_ANT_DIV_COMB_LNA2;
1734                                 div_ant_conf.alt_lna_conf =
1735                                                 ATH_ANT_DIV_COMB_LNA1;
1736                         } else if (curr_main_set == ATH_ANT_DIV_COMB_LNA1) {
1737                                 div_ant_conf.main_lna_conf =
1738                                                 ATH_ANT_DIV_COMB_LNA1;
1739                                 div_ant_conf.alt_lna_conf =
1740                                                 ATH_ANT_DIV_COMB_LNA2;
1741                         }
1742                         goto div_comb_done;
1743                 }
1744         }
1745
1746         ath_select_ant_div_from_quick_scan(antcomb, &div_ant_conf,
1747                                            main_rssi_avg, alt_rssi_avg,
1748                                            alt_ratio);
1749
1750         antcomb->quick_scan_cnt++;
1751
1752 div_comb_done:
1753         ath_ant_div_conf_fast_divbias(&div_ant_conf, antcomb, alt_ratio);
1754         ath9k_hw_antdiv_comb_conf_set(sc->sc_ah, &div_ant_conf);
1755
1756         antcomb->scan_start_time = jiffies;
1757         antcomb->total_pkt_count = 0;
1758         antcomb->main_total_rssi = 0;
1759         antcomb->alt_total_rssi = 0;
1760         antcomb->main_recv_cnt = 0;
1761         antcomb->alt_recv_cnt = 0;
1762 }
1763
1764 int ath_rx_tasklet(struct ath_softc *sc, int flush, bool hp)
1765 {
1766         struct ath_buf *bf;
1767         struct sk_buff *skb = NULL, *requeue_skb, *hdr_skb;
1768         struct ieee80211_rx_status *rxs;
1769         struct ath_hw *ah = sc->sc_ah;
1770         struct ath_common *common = ath9k_hw_common(ah);
1771         struct ieee80211_hw *hw = sc->hw;
1772         struct ieee80211_hdr *hdr;
1773         int retval;
1774         bool decrypt_error = false;
1775         struct ath_rx_status rs;
1776         enum ath9k_rx_qtype qtype;
1777         bool edma = !!(ah->caps.hw_caps & ATH9K_HW_CAP_EDMA);
1778         int dma_type;
1779         u8 rx_status_len = ah->caps.rx_status_len;
1780         u64 tsf = 0;
1781         u32 tsf_lower = 0;
1782         unsigned long flags;
1783
1784         if (edma)
1785                 dma_type = DMA_BIDIRECTIONAL;
1786         else
1787                 dma_type = DMA_FROM_DEVICE;
1788
1789         qtype = hp ? ATH9K_RX_QUEUE_HP : ATH9K_RX_QUEUE_LP;
1790         spin_lock_bh(&sc->rx.rxbuflock);
1791
1792         tsf = ath9k_hw_gettsf64(ah);
1793         tsf_lower = tsf & 0xffffffff;
1794
1795         do {
1796                 /* If handling rx interrupt and flush is in progress => exit */
1797                 if ((sc->sc_flags & SC_OP_RXFLUSH) && (flush == 0))
1798                         break;
1799
1800                 memset(&rs, 0, sizeof(rs));
1801                 if (edma)
1802                         bf = ath_edma_get_next_rx_buf(sc, &rs, qtype);
1803                 else
1804                         bf = ath_get_next_rx_buf(sc, &rs);
1805
1806                 if (!bf)
1807                         break;
1808
1809                 skb = bf->bf_mpdu;
1810                 if (!skb)
1811                         continue;
1812
1813                 /*
1814                  * Take frame header from the first fragment and RX status from
1815                  * the last one.
1816                  */
1817                 if (sc->rx.frag)
1818                         hdr_skb = sc->rx.frag;
1819                 else
1820                         hdr_skb = skb;
1821
1822                 hdr = (struct ieee80211_hdr *) (hdr_skb->data + rx_status_len);
1823                 rxs = IEEE80211_SKB_RXCB(hdr_skb);
1824                 if (ieee80211_is_beacon(hdr->frame_control) &&
1825                     !compare_ether_addr(hdr->addr3, common->curbssid))
1826                         rs.is_mybeacon = true;
1827                 else
1828                         rs.is_mybeacon = false;
1829
1830                 ath_debug_stat_rx(sc, &rs);
1831
1832                 /*
1833                  * If we're asked to flush receive queue, directly
1834                  * chain it back at the queue without processing it.
1835                  */
1836                 if (sc->sc_flags & SC_OP_RXFLUSH)
1837                         goto requeue_drop_frag;
1838
1839                 retval = ath9k_rx_skb_preprocess(common, hw, hdr, &rs,
1840                                                  rxs, &decrypt_error);
1841                 if (retval)
1842                         goto requeue_drop_frag;
1843
1844                 rxs->mactime = (tsf & ~0xffffffffULL) | rs.rs_tstamp;
1845                 if (rs.rs_tstamp > tsf_lower &&
1846                     unlikely(rs.rs_tstamp - tsf_lower > 0x10000000))
1847                         rxs->mactime -= 0x100000000ULL;
1848
1849                 if (rs.rs_tstamp < tsf_lower &&
1850                     unlikely(tsf_lower - rs.rs_tstamp > 0x10000000))
1851                         rxs->mactime += 0x100000000ULL;
1852
1853                 /* Ensure we always have an skb to requeue once we are done
1854                  * processing the current buffer's skb */
1855                 requeue_skb = ath_rxbuf_alloc(common, common->rx_bufsize, GFP_ATOMIC);
1856
1857                 /* If there is no memory we ignore the current RX'd frame,
1858                  * tell hardware it can give us a new frame using the old
1859                  * skb and put it at the tail of the sc->rx.rxbuf list for
1860                  * processing. */
1861                 if (!requeue_skb)
1862                         goto requeue_drop_frag;
1863
1864                 /* Unmap the frame */
1865                 dma_unmap_single(sc->dev, bf->bf_buf_addr,
1866                                  common->rx_bufsize,
1867                                  dma_type);
1868
1869                 skb_put(skb, rs.rs_datalen + ah->caps.rx_status_len);
1870                 if (ah->caps.rx_status_len)
1871                         skb_pull(skb, ah->caps.rx_status_len);
1872
1873                 if (!rs.rs_more)
1874                         ath9k_rx_skb_postprocess(common, hdr_skb, &rs,
1875                                                  rxs, decrypt_error);
1876
1877                 /* We will now give hardware our shiny new allocated skb */
1878                 bf->bf_mpdu = requeue_skb;
1879                 bf->bf_buf_addr = dma_map_single(sc->dev, requeue_skb->data,
1880                                                  common->rx_bufsize,
1881                                                  dma_type);
1882                 if (unlikely(dma_mapping_error(sc->dev,
1883                           bf->bf_buf_addr))) {
1884                         dev_kfree_skb_any(requeue_skb);
1885                         bf->bf_mpdu = NULL;
1886                         bf->bf_buf_addr = 0;
1887                         ath_err(common, "dma_mapping_error() on RX\n");
1888                         ieee80211_rx(hw, skb);
1889                         break;
1890                 }
1891
1892                 if (rs.rs_more) {
1893                         /*
1894                          * rs_more indicates chained descriptors which can be
1895                          * used to link buffers together for a sort of
1896                          * scatter-gather operation.
1897                          */
1898                         if (sc->rx.frag) {
1899                                 /* too many fragments - cannot handle frame */
1900                                 dev_kfree_skb_any(sc->rx.frag);
1901                                 dev_kfree_skb_any(skb);
1902                                 skb = NULL;
1903                         }
1904                         sc->rx.frag = skb;
1905                         goto requeue;
1906                 }
1907
1908                 if (sc->rx.frag) {
1909                         int space = skb->len - skb_tailroom(hdr_skb);
1910
1911                         sc->rx.frag = NULL;
1912
1913                         if (pskb_expand_head(hdr_skb, 0, space, GFP_ATOMIC) < 0) {
1914                                 dev_kfree_skb(skb);
1915                                 goto requeue_drop_frag;
1916                         }
1917
1918                         skb_copy_from_linear_data(skb, skb_put(hdr_skb, skb->len),
1919                                                   skb->len);
1920                         dev_kfree_skb_any(skb);
1921                         skb = hdr_skb;
1922                 }
1923
1924                 /*
1925                  * change the default rx antenna if rx diversity chooses the
1926                  * other antenna 3 times in a row.
1927                  */
1928                 if (sc->rx.defant != rs.rs_antenna) {
1929                         if (++sc->rx.rxotherant >= 3)
1930                                 ath_setdefantenna(sc, rs.rs_antenna);
1931                 } else {
1932                         sc->rx.rxotherant = 0;
1933                 }
1934
1935                 if (rxs->flag & RX_FLAG_MMIC_STRIPPED)
1936                         skb_trim(skb, skb->len - 8);
1937
1938                 spin_lock_irqsave(&sc->sc_pm_lock, flags);
1939
1940                 if ((sc->ps_flags & (PS_WAIT_FOR_BEACON |
1941                                      PS_WAIT_FOR_CAB |
1942                                      PS_WAIT_FOR_PSPOLL_DATA)) ||
1943                     ath9k_check_auto_sleep(sc))
1944                         ath_rx_ps(sc, skb, rs.is_mybeacon);
1945                 spin_unlock_irqrestore(&sc->sc_pm_lock, flags);
1946
1947                 if ((ah->caps.hw_caps & ATH9K_HW_CAP_ANT_DIV_COMB) && sc->ant_rx == 3)
1948                         ath_ant_comb_scan(sc, &rs);
1949
1950                 ieee80211_rx(hw, skb);
1951
1952 requeue_drop_frag:
1953                 if (sc->rx.frag) {
1954                         dev_kfree_skb_any(sc->rx.frag);
1955                         sc->rx.frag = NULL;
1956                 }
1957 requeue:
1958                 if (edma) {
1959                         list_add_tail(&bf->list, &sc->rx.rxbuf);
1960                         ath_rx_edma_buf_link(sc, qtype);
1961                 } else {
1962                         list_move_tail(&bf->list, &sc->rx.rxbuf);
1963                         ath_rx_buf_link(sc, bf);
1964                         if (!flush)
1965                                 ath9k_hw_rxena(ah);
1966                 }
1967         } while (1);
1968
1969         spin_unlock_bh(&sc->rx.rxbuflock);
1970
1971         if (!(ah->imask & ATH9K_INT_RXEOL)) {
1972                 ah->imask |= (ATH9K_INT_RXEOL | ATH9K_INT_RXORN);
1973                 ath9k_hw_set_interrupts(ah, ah->imask);
1974         }
1975
1976         return 0;
1977 }