ath9k: Use common ath key management functions
[linux-2.6-block.git] / drivers / net / wireless / ath / ath9k / recv.c
index e3e52913d83a49326e3319cd67e1a0275b302d39..6fb3b4536045bebb133be9d5d9a1833ed690ee09 100644 (file)
 
 #define SKB_CB_ATHBUF(__skb)   (*((struct ath_buf **)__skb->cb))
 
+static inline bool ath_is_alt_ant_ratio_better(int alt_ratio, int maxdelta,
+                                              int mindelta, int main_rssi_avg,
+                                              int alt_rssi_avg, int pkt_count)
+{
+       return (((alt_ratio >= ATH_ANT_DIV_COMB_ALT_ANT_RATIO2) &&
+               (alt_rssi_avg > main_rssi_avg + maxdelta)) ||
+               (alt_rssi_avg > main_rssi_avg + mindelta)) && (pkt_count > 50);
+}
+
 static inline bool ath9k_check_auto_sleep(struct ath_softc *sc)
 {
        return sc->ps_enabled &&
@@ -110,15 +119,11 @@ static void ath_opmode_init(struct ath_softc *sc)
        ath9k_hw_setrxfilter(ah, rfilt);
 
        /* configure bssid mask */
-       if (ah->caps.hw_caps & ATH9K_HW_CAP_BSSIDMASK)
-               ath_hw_setbssidmask(common);
+       ath_hw_setbssidmask(common);
 
        /* configure operational mode */
        ath9k_hw_setopmode(ah);
 
-       /* Handle any link-level address change. */
-       ath9k_hw_setmac(ah, common->macaddr);
-
        /* calculate and install multicast filter */
        mfilt[0] = mfilt[1] = ~0;
        ath9k_hw_setmcastfilter(ah, mfilt[0], mfilt[1]);
@@ -295,7 +300,7 @@ static void ath_edma_start_recv(struct ath_softc *sc)
 
        ath_opmode_init(sc);
 
-       ath9k_hw_startpcureceive(sc->sc_ah);
+       ath9k_hw_startpcureceive(sc->sc_ah, (sc->sc_flags & SC_OP_SCANNING));
 }
 
 static void ath_edma_stop_recv(struct ath_softc *sc)
@@ -501,7 +506,7 @@ int ath_startrecv(struct ath_softc *sc)
 start_recv:
        spin_unlock_bh(&sc->rx.rxbuflock);
        ath_opmode_init(sc);
-       ath9k_hw_startpcureceive(ah);
+       ath9k_hw_startpcureceive(ah, (sc->sc_flags & SC_OP_SCANNING));
 
        return 0;
 }
@@ -700,12 +705,16 @@ static bool ath_edma_get_buffers(struct ath_softc *sc,
        bf = SKB_CB_ATHBUF(skb);
        BUG_ON(!bf);
 
-       dma_sync_single_for_device(sc->dev, bf->bf_buf_addr,
+       dma_sync_single_for_cpu(sc->dev, bf->bf_buf_addr,
                                common->rx_bufsize, DMA_FROM_DEVICE);
 
        ret = ath9k_hw_process_rxdesc_edma(ah, NULL, skb->data);
-       if (ret == -EINPROGRESS)
+       if (ret == -EINPROGRESS) {
+               /*let device gain the buffer again*/
+               dma_sync_single_for_device(sc->dev, bf->bf_buf_addr,
+                               common->rx_bufsize, DMA_FROM_DEVICE);
                return false;
+       }
 
        __skb_unlink(skb, &rx_edma->rx_fifo);
        if (ret == -EINVAL) {
@@ -814,13 +823,799 @@ static struct ath_buf *ath_get_next_rx_buf(struct ath_softc *sc,
         * 1. accessing the frame
         * 2. requeueing the same buffer to h/w
         */
-       dma_sync_single_for_device(sc->dev, bf->bf_buf_addr,
+       dma_sync_single_for_cpu(sc->dev, bf->bf_buf_addr,
                        common->rx_bufsize,
                        DMA_FROM_DEVICE);
 
        return bf;
 }
 
+/* Assumes you've already done the endian to CPU conversion */
+static bool ath9k_rx_accept(struct ath_common *common,
+                           struct ieee80211_hdr *hdr,
+                           struct ieee80211_rx_status *rxs,
+                           struct ath_rx_status *rx_stats,
+                           bool *decrypt_error)
+{
+       struct ath_hw *ah = common->ah;
+       __le16 fc;
+       u8 rx_status_len = ah->caps.rx_status_len;
+
+       fc = hdr->frame_control;
+
+       if (!rx_stats->rs_datalen)
+               return false;
+        /*
+         * rs_status follows rs_datalen so if rs_datalen is too large
+         * we can take a hint that hardware corrupted it, so ignore
+         * those frames.
+         */
+       if (rx_stats->rs_datalen > (common->rx_bufsize - rx_status_len))
+               return false;
+
+       /*
+        * rs_more indicates chained descriptors which can be used
+        * to link buffers together for a sort of scatter-gather
+        * operation.
+        * reject the frame, we don't support scatter-gather yet and
+        * the frame is probably corrupt anyway
+        */
+       if (rx_stats->rs_more)
+               return false;
+
+       /*
+        * The rx_stats->rs_status will not be set until the end of the
+        * chained descriptors so it can be ignored if rs_more is set. The
+        * rs_more will be false at the last element of the chained
+        * descriptors.
+        */
+       if (rx_stats->rs_status != 0) {
+               if (rx_stats->rs_status & ATH9K_RXERR_CRC)
+                       rxs->flag |= RX_FLAG_FAILED_FCS_CRC;
+               if (rx_stats->rs_status & ATH9K_RXERR_PHY)
+                       return false;
+
+               if (rx_stats->rs_status & ATH9K_RXERR_DECRYPT) {
+                       *decrypt_error = true;
+               } else if (rx_stats->rs_status & ATH9K_RXERR_MIC) {
+                       /*
+                        * The MIC error bit is only valid if the frame
+                        * is not a control frame or fragment, and it was
+                        * decrypted using a valid TKIP key.
+                        */
+                       if (!ieee80211_is_ctl(fc) &&
+                           !ieee80211_has_morefrags(fc) &&
+                           !(le16_to_cpu(hdr->seq_ctrl) & IEEE80211_SCTL_FRAG) &&
+                           test_bit(rx_stats->rs_keyix, common->tkip_keymap))
+                               rxs->flag |= RX_FLAG_MMIC_ERROR;
+                       else
+                               rx_stats->rs_status &= ~ATH9K_RXERR_MIC;
+               }
+               /*
+                * Reject error frames with the exception of
+                * decryption and MIC failures. For monitor mode,
+                * we also ignore the CRC error.
+                */
+               if (ah->opmode == NL80211_IFTYPE_MONITOR) {
+                       if (rx_stats->rs_status &
+                           ~(ATH9K_RXERR_DECRYPT | ATH9K_RXERR_MIC |
+                             ATH9K_RXERR_CRC))
+                               return false;
+               } else {
+                       if (rx_stats->rs_status &
+                           ~(ATH9K_RXERR_DECRYPT | ATH9K_RXERR_MIC)) {
+                               return false;
+                       }
+               }
+       }
+       return true;
+}
+
+static int ath9k_process_rate(struct ath_common *common,
+                             struct ieee80211_hw *hw,
+                             struct ath_rx_status *rx_stats,
+                             struct ieee80211_rx_status *rxs)
+{
+       struct ieee80211_supported_band *sband;
+       enum ieee80211_band band;
+       unsigned int i = 0;
+
+       band = hw->conf.channel->band;
+       sband = hw->wiphy->bands[band];
+
+       if (rx_stats->rs_rate & 0x80) {
+               /* HT rate */
+               rxs->flag |= RX_FLAG_HT;
+               if (rx_stats->rs_flags & ATH9K_RX_2040)
+                       rxs->flag |= RX_FLAG_40MHZ;
+               if (rx_stats->rs_flags & ATH9K_RX_GI)
+                       rxs->flag |= RX_FLAG_SHORT_GI;
+               rxs->rate_idx = rx_stats->rs_rate & 0x7f;
+               return 0;
+       }
+
+       for (i = 0; i < sband->n_bitrates; i++) {
+               if (sband->bitrates[i].hw_value == rx_stats->rs_rate) {
+                       rxs->rate_idx = i;
+                       return 0;
+               }
+               if (sband->bitrates[i].hw_value_short == rx_stats->rs_rate) {
+                       rxs->flag |= RX_FLAG_SHORTPRE;
+                       rxs->rate_idx = i;
+                       return 0;
+               }
+       }
+
+       /*
+        * No valid hardware bitrate found -- we should not get here
+        * because hardware has already validated this frame as OK.
+        */
+       ath_print(common, ATH_DBG_XMIT, "unsupported hw bitrate detected "
+                 "0x%02x using 1 Mbit\n", rx_stats->rs_rate);
+
+       return -EINVAL;
+}
+
+static void ath9k_process_rssi(struct ath_common *common,
+                              struct ieee80211_hw *hw,
+                              struct ieee80211_hdr *hdr,
+                              struct ath_rx_status *rx_stats)
+{
+       struct ath_hw *ah = common->ah;
+       struct ieee80211_sta *sta;
+       struct ath_node *an;
+       int last_rssi = ATH_RSSI_DUMMY_MARKER;
+       __le16 fc;
+
+       fc = hdr->frame_control;
+
+       rcu_read_lock();
+       /*
+        * XXX: use ieee80211_find_sta! This requires quite a bit of work
+        * under the current ath9k virtual wiphy implementation as we have
+        * no way of tying a vif to wiphy. Typically vifs are attached to
+        * at least one sdata of a wiphy on mac80211 but with ath9k virtual
+        * wiphy you'd have to iterate over every wiphy and each sdata.
+        */
+       sta = ieee80211_find_sta_by_hw(hw, hdr->addr2);
+       if (sta) {
+               an = (struct ath_node *) sta->drv_priv;
+               if (rx_stats->rs_rssi != ATH9K_RSSI_BAD &&
+                  !rx_stats->rs_moreaggr)
+                       ATH_RSSI_LPF(an->last_rssi, rx_stats->rs_rssi);
+               last_rssi = an->last_rssi;
+       }
+       rcu_read_unlock();
+
+       if (likely(last_rssi != ATH_RSSI_DUMMY_MARKER))
+               rx_stats->rs_rssi = ATH_EP_RND(last_rssi,
+                                             ATH_RSSI_EP_MULTIPLIER);
+       if (rx_stats->rs_rssi < 0)
+               rx_stats->rs_rssi = 0;
+
+       /* Update Beacon RSSI, this is used by ANI. */
+       if (ieee80211_is_beacon(fc))
+               ah->stats.avgbrssi = rx_stats->rs_rssi;
+}
+
+/*
+ * For Decrypt or Demic errors, we only mark packet status here and always push
+ * up the frame up to let mac80211 handle the actual error case, be it no
+ * decryption key or real decryption error. This let us keep statistics there.
+ */
+static int ath9k_rx_skb_preprocess(struct ath_common *common,
+                                  struct ieee80211_hw *hw,
+                                  struct ieee80211_hdr *hdr,
+                                  struct ath_rx_status *rx_stats,
+                                  struct ieee80211_rx_status *rx_status,
+                                  bool *decrypt_error)
+{
+       memset(rx_status, 0, sizeof(struct ieee80211_rx_status));
+
+       /*
+        * everything but the rate is checked here, the rate check is done
+        * separately to avoid doing two lookups for a rate for each frame.
+        */
+       if (!ath9k_rx_accept(common, hdr, rx_status, rx_stats, decrypt_error))
+               return -EINVAL;
+
+       ath9k_process_rssi(common, hw, hdr, rx_stats);
+
+       if (ath9k_process_rate(common, hw, rx_stats, rx_status))
+               return -EINVAL;
+
+       rx_status->band = hw->conf.channel->band;
+       rx_status->freq = hw->conf.channel->center_freq;
+       rx_status->signal = ATH_DEFAULT_NOISE_FLOOR + rx_stats->rs_rssi;
+       rx_status->antenna = rx_stats->rs_antenna;
+       rx_status->flag |= RX_FLAG_TSFT;
+
+       return 0;
+}
+
+static void ath9k_rx_skb_postprocess(struct ath_common *common,
+                                    struct sk_buff *skb,
+                                    struct ath_rx_status *rx_stats,
+                                    struct ieee80211_rx_status *rxs,
+                                    bool decrypt_error)
+{
+       struct ath_hw *ah = common->ah;
+       struct ieee80211_hdr *hdr;
+       int hdrlen, padpos, padsize;
+       u8 keyix;
+       __le16 fc;
+
+       /* see if any padding is done by the hw and remove it */
+       hdr = (struct ieee80211_hdr *) skb->data;
+       hdrlen = ieee80211_get_hdrlen_from_skb(skb);
+       fc = hdr->frame_control;
+       padpos = ath9k_cmn_padpos(hdr->frame_control);
+
+       /* The MAC header is padded to have 32-bit boundary if the
+        * packet payload is non-zero. The general calculation for
+        * padsize would take into account odd header lengths:
+        * padsize = (4 - padpos % 4) % 4; However, since only
+        * even-length headers are used, padding can only be 0 or 2
+        * bytes and we can optimize this a bit. In addition, we must
+        * not try to remove padding from short control frames that do
+        * not have payload. */
+       padsize = padpos & 3;
+       if (padsize && skb->len>=padpos+padsize+FCS_LEN) {
+               memmove(skb->data + padsize, skb->data, padpos);
+               skb_pull(skb, padsize);
+       }
+
+       keyix = rx_stats->rs_keyix;
+
+       if (!(keyix == ATH9K_RXKEYIX_INVALID) && !decrypt_error &&
+           ieee80211_has_protected(fc)) {
+               rxs->flag |= RX_FLAG_DECRYPTED;
+       } else if (ieee80211_has_protected(fc)
+                  && !decrypt_error && skb->len >= hdrlen + 4) {
+               keyix = skb->data[hdrlen + 3] >> 6;
+
+               if (test_bit(keyix, common->keymap))
+                       rxs->flag |= RX_FLAG_DECRYPTED;
+       }
+       if (ah->sw_mgmt_crypto &&
+           (rxs->flag & RX_FLAG_DECRYPTED) &&
+           ieee80211_is_mgmt(fc))
+               /* Use software decrypt for management frames. */
+               rxs->flag &= ~RX_FLAG_DECRYPTED;
+}
+
+static void ath_lnaconf_alt_good_scan(struct ath_ant_comb *antcomb,
+                                     struct ath_hw_antcomb_conf ant_conf,
+                                     int main_rssi_avg)
+{
+       antcomb->quick_scan_cnt = 0;
+
+       if (ant_conf.main_lna_conf == ATH_ANT_DIV_COMB_LNA2)
+               antcomb->rssi_lna2 = main_rssi_avg;
+       else if (ant_conf.main_lna_conf == ATH_ANT_DIV_COMB_LNA1)
+               antcomb->rssi_lna1 = main_rssi_avg;
+
+       switch ((ant_conf.main_lna_conf << 4) | ant_conf.alt_lna_conf) {
+       case (0x10): /* LNA2 A-B */
+               antcomb->main_conf = ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
+               antcomb->first_quick_scan_conf =
+                       ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
+               antcomb->second_quick_scan_conf = ATH_ANT_DIV_COMB_LNA1;
+               break;
+       case (0x20): /* LNA1 A-B */
+               antcomb->main_conf = ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
+               antcomb->first_quick_scan_conf =
+                       ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
+               antcomb->second_quick_scan_conf = ATH_ANT_DIV_COMB_LNA2;
+               break;
+       case (0x21): /* LNA1 LNA2 */
+               antcomb->main_conf = ATH_ANT_DIV_COMB_LNA2;
+               antcomb->first_quick_scan_conf =
+                       ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
+               antcomb->second_quick_scan_conf =
+                       ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
+               break;
+       case (0x12): /* LNA2 LNA1 */
+               antcomb->main_conf = ATH_ANT_DIV_COMB_LNA1;
+               antcomb->first_quick_scan_conf =
+                       ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
+               antcomb->second_quick_scan_conf =
+                       ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
+               break;
+       case (0x13): /* LNA2 A+B */
+               antcomb->main_conf = ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
+               antcomb->first_quick_scan_conf =
+                       ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
+               antcomb->second_quick_scan_conf = ATH_ANT_DIV_COMB_LNA1;
+               break;
+       case (0x23): /* LNA1 A+B */
+               antcomb->main_conf = ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
+               antcomb->first_quick_scan_conf =
+                       ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
+               antcomb->second_quick_scan_conf = ATH_ANT_DIV_COMB_LNA2;
+               break;
+       default:
+               break;
+       }
+}
+
+static void ath_select_ant_div_from_quick_scan(struct ath_ant_comb *antcomb,
+                               struct ath_hw_antcomb_conf *div_ant_conf,
+                               int main_rssi_avg, int alt_rssi_avg,
+                               int alt_ratio)
+{
+       /* alt_good */
+       switch (antcomb->quick_scan_cnt) {
+       case 0:
+               /* set alt to main, and alt to first conf */
+               div_ant_conf->main_lna_conf = antcomb->main_conf;
+               div_ant_conf->alt_lna_conf = antcomb->first_quick_scan_conf;
+               break;
+       case 1:
+               /* set alt to main, and alt to first conf */
+               div_ant_conf->main_lna_conf = antcomb->main_conf;
+               div_ant_conf->alt_lna_conf = antcomb->second_quick_scan_conf;
+               antcomb->rssi_first = main_rssi_avg;
+               antcomb->rssi_second = alt_rssi_avg;
+
+               if (antcomb->main_conf == ATH_ANT_DIV_COMB_LNA1) {
+                       /* main is LNA1 */
+                       if (ath_is_alt_ant_ratio_better(alt_ratio,
+                                               ATH_ANT_DIV_COMB_LNA1_DELTA_HI,
+                                               ATH_ANT_DIV_COMB_LNA1_DELTA_LOW,
+                                               main_rssi_avg, alt_rssi_avg,
+                                               antcomb->total_pkt_count))
+                               antcomb->first_ratio = true;
+                       else
+                               antcomb->first_ratio = false;
+               } else if (antcomb->main_conf == ATH_ANT_DIV_COMB_LNA2) {
+                       if (ath_is_alt_ant_ratio_better(alt_ratio,
+                                               ATH_ANT_DIV_COMB_LNA1_DELTA_MID,
+                                               ATH_ANT_DIV_COMB_LNA1_DELTA_LOW,
+                                               main_rssi_avg, alt_rssi_avg,
+                                               antcomb->total_pkt_count))
+                               antcomb->first_ratio = true;
+                       else
+                               antcomb->first_ratio = false;
+               } else {
+                       if ((((alt_ratio >= ATH_ANT_DIV_COMB_ALT_ANT_RATIO2) &&
+                           (alt_rssi_avg > main_rssi_avg +
+                           ATH_ANT_DIV_COMB_LNA1_DELTA_HI)) ||
+                           (alt_rssi_avg > main_rssi_avg)) &&
+                           (antcomb->total_pkt_count > 50))
+                               antcomb->first_ratio = true;
+                       else
+                               antcomb->first_ratio = false;
+               }
+               break;
+       case 2:
+               antcomb->alt_good = false;
+               antcomb->scan_not_start = false;
+               antcomb->scan = false;
+               antcomb->rssi_first = main_rssi_avg;
+               antcomb->rssi_third = alt_rssi_avg;
+
+               if (antcomb->second_quick_scan_conf == ATH_ANT_DIV_COMB_LNA1)
+                       antcomb->rssi_lna1 = alt_rssi_avg;
+               else if (antcomb->second_quick_scan_conf ==
+                        ATH_ANT_DIV_COMB_LNA2)
+                       antcomb->rssi_lna2 = alt_rssi_avg;
+               else if (antcomb->second_quick_scan_conf ==
+                        ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2) {
+                       if (antcomb->main_conf == ATH_ANT_DIV_COMB_LNA2)
+                               antcomb->rssi_lna2 = main_rssi_avg;
+                       else if (antcomb->main_conf == ATH_ANT_DIV_COMB_LNA1)
+                               antcomb->rssi_lna1 = main_rssi_avg;
+               }
+
+               if (antcomb->rssi_lna2 > antcomb->rssi_lna1 +
+                   ATH_ANT_DIV_COMB_LNA1_LNA2_SWITCH_DELTA)
+                       div_ant_conf->main_lna_conf = ATH_ANT_DIV_COMB_LNA2;
+               else
+                       div_ant_conf->main_lna_conf = ATH_ANT_DIV_COMB_LNA1;
+
+               if (antcomb->main_conf == ATH_ANT_DIV_COMB_LNA1) {
+                       if (ath_is_alt_ant_ratio_better(alt_ratio,
+                                               ATH_ANT_DIV_COMB_LNA1_DELTA_HI,
+                                               ATH_ANT_DIV_COMB_LNA1_DELTA_LOW,
+                                               main_rssi_avg, alt_rssi_avg,
+                                               antcomb->total_pkt_count))
+                               antcomb->second_ratio = true;
+                       else
+                               antcomb->second_ratio = false;
+               } else if (antcomb->main_conf == ATH_ANT_DIV_COMB_LNA2) {
+                       if (ath_is_alt_ant_ratio_better(alt_ratio,
+                                               ATH_ANT_DIV_COMB_LNA1_DELTA_MID,
+                                               ATH_ANT_DIV_COMB_LNA1_DELTA_LOW,
+                                               main_rssi_avg, alt_rssi_avg,
+                                               antcomb->total_pkt_count))
+                               antcomb->second_ratio = true;
+                       else
+                               antcomb->second_ratio = false;
+               } else {
+                       if ((((alt_ratio >= ATH_ANT_DIV_COMB_ALT_ANT_RATIO2) &&
+                           (alt_rssi_avg > main_rssi_avg +
+                           ATH_ANT_DIV_COMB_LNA1_DELTA_HI)) ||
+                           (alt_rssi_avg > main_rssi_avg)) &&
+                           (antcomb->total_pkt_count > 50))
+                               antcomb->second_ratio = true;
+                       else
+                               antcomb->second_ratio = false;
+               }
+
+               /* set alt to the conf with maximun ratio */
+               if (antcomb->first_ratio && antcomb->second_ratio) {
+                       if (antcomb->rssi_second > antcomb->rssi_third) {
+                               /* first alt*/
+                               if ((antcomb->first_quick_scan_conf ==
+                                   ATH_ANT_DIV_COMB_LNA1) ||
+                                   (antcomb->first_quick_scan_conf ==
+                                   ATH_ANT_DIV_COMB_LNA2))
+                                       /* Set alt LNA1 or LNA2*/
+                                       if (div_ant_conf->main_lna_conf ==
+                                           ATH_ANT_DIV_COMB_LNA2)
+                                               div_ant_conf->alt_lna_conf =
+                                                       ATH_ANT_DIV_COMB_LNA1;
+                                       else
+                                               div_ant_conf->alt_lna_conf =
+                                                       ATH_ANT_DIV_COMB_LNA2;
+                               else
+                                       /* Set alt to A+B or A-B */
+                                       div_ant_conf->alt_lna_conf =
+                                               antcomb->first_quick_scan_conf;
+                       } else if ((antcomb->second_quick_scan_conf ==
+                                  ATH_ANT_DIV_COMB_LNA1) ||
+                                  (antcomb->second_quick_scan_conf ==
+                                  ATH_ANT_DIV_COMB_LNA2)) {
+                               /* Set alt LNA1 or LNA2 */
+                               if (div_ant_conf->main_lna_conf ==
+                                   ATH_ANT_DIV_COMB_LNA2)
+                                       div_ant_conf->alt_lna_conf =
+                                               ATH_ANT_DIV_COMB_LNA1;
+                               else
+                                       div_ant_conf->alt_lna_conf =
+                                               ATH_ANT_DIV_COMB_LNA2;
+                       } else {
+                               /* Set alt to A+B or A-B */
+                               div_ant_conf->alt_lna_conf =
+                                       antcomb->second_quick_scan_conf;
+                       }
+               } else if (antcomb->first_ratio) {
+                       /* first alt */
+                       if ((antcomb->first_quick_scan_conf ==
+                           ATH_ANT_DIV_COMB_LNA1) ||
+                           (antcomb->first_quick_scan_conf ==
+                           ATH_ANT_DIV_COMB_LNA2))
+                                       /* Set alt LNA1 or LNA2 */
+                               if (div_ant_conf->main_lna_conf ==
+                                   ATH_ANT_DIV_COMB_LNA2)
+                                       div_ant_conf->alt_lna_conf =
+                                                       ATH_ANT_DIV_COMB_LNA1;
+                               else
+                                       div_ant_conf->alt_lna_conf =
+                                                       ATH_ANT_DIV_COMB_LNA2;
+                       else
+                               /* Set alt to A+B or A-B */
+                               div_ant_conf->alt_lna_conf =
+                                               antcomb->first_quick_scan_conf;
+               } else if (antcomb->second_ratio) {
+                               /* second alt */
+                       if ((antcomb->second_quick_scan_conf ==
+                           ATH_ANT_DIV_COMB_LNA1) ||
+                           (antcomb->second_quick_scan_conf ==
+                           ATH_ANT_DIV_COMB_LNA2))
+                               /* Set alt LNA1 or LNA2 */
+                               if (div_ant_conf->main_lna_conf ==
+                                   ATH_ANT_DIV_COMB_LNA2)
+                                       div_ant_conf->alt_lna_conf =
+                                               ATH_ANT_DIV_COMB_LNA1;
+                               else
+                                       div_ant_conf->alt_lna_conf =
+                                               ATH_ANT_DIV_COMB_LNA2;
+                       else
+                               /* Set alt to A+B or A-B */
+                               div_ant_conf->alt_lna_conf =
+                                               antcomb->second_quick_scan_conf;
+               } else {
+                       /* main is largest */
+                       if ((antcomb->main_conf == ATH_ANT_DIV_COMB_LNA1) ||
+                           (antcomb->main_conf == ATH_ANT_DIV_COMB_LNA2))
+                               /* Set alt LNA1 or LNA2 */
+                               if (div_ant_conf->main_lna_conf ==
+                                   ATH_ANT_DIV_COMB_LNA2)
+                                       div_ant_conf->alt_lna_conf =
+                                                       ATH_ANT_DIV_COMB_LNA1;
+                               else
+                                       div_ant_conf->alt_lna_conf =
+                                                       ATH_ANT_DIV_COMB_LNA2;
+                       else
+                               /* Set alt to A+B or A-B */
+                               div_ant_conf->alt_lna_conf = antcomb->main_conf;
+               }
+               break;
+       default:
+               break;
+       }
+}
+
+void ath_ant_div_conf_fast_divbias(struct ath_hw_antcomb_conf *ant_conf)
+{
+       /* Adjust the fast_div_bias based on main and alt lna conf */
+       switch ((ant_conf->main_lna_conf << 4) | ant_conf->alt_lna_conf) {
+       case (0x01): /* A-B LNA2 */
+               ant_conf->fast_div_bias = 0x3b;
+               break;
+       case (0x02): /* A-B LNA1 */
+               ant_conf->fast_div_bias = 0x3d;
+               break;
+       case (0x03): /* A-B A+B */
+               ant_conf->fast_div_bias = 0x1;
+               break;
+       case (0x10): /* LNA2 A-B */
+               ant_conf->fast_div_bias = 0x7;
+               break;
+       case (0x12): /* LNA2 LNA1 */
+               ant_conf->fast_div_bias = 0x2;
+               break;
+       case (0x13): /* LNA2 A+B */
+               ant_conf->fast_div_bias = 0x7;
+               break;
+       case (0x20): /* LNA1 A-B */
+               ant_conf->fast_div_bias = 0x6;
+               break;
+       case (0x21): /* LNA1 LNA2 */
+               ant_conf->fast_div_bias = 0x0;
+               break;
+       case (0x23): /* LNA1 A+B */
+               ant_conf->fast_div_bias = 0x6;
+               break;
+       case (0x30): /* A+B A-B */
+               ant_conf->fast_div_bias = 0x1;
+               break;
+       case (0x31): /* A+B LNA2 */
+               ant_conf->fast_div_bias = 0x3b;
+               break;
+       case (0x32): /* A+B LNA1 */
+               ant_conf->fast_div_bias = 0x3d;
+               break;
+       default:
+               break;
+       }
+}
+
+/* Antenna diversity and combining */
+static void ath_ant_comb_scan(struct ath_softc *sc, struct ath_rx_status *rs)
+{
+       struct ath_hw_antcomb_conf div_ant_conf;
+       struct ath_ant_comb *antcomb = &sc->ant_comb;
+       int alt_ratio = 0, alt_rssi_avg = 0, main_rssi_avg = 0, curr_alt_set;
+       int curr_main_set, curr_bias;
+       int main_rssi = rs->rs_rssi_ctl0;
+       int alt_rssi = rs->rs_rssi_ctl1;
+       int rx_ant_conf,  main_ant_conf;
+       bool short_scan = false;
+
+       rx_ant_conf = (rs->rs_rssi_ctl2 >> ATH_ANT_RX_CURRENT_SHIFT) &
+                      ATH_ANT_RX_MASK;
+       main_ant_conf = (rs->rs_rssi_ctl2 >> ATH_ANT_RX_MAIN_SHIFT) &
+                        ATH_ANT_RX_MASK;
+
+       /* Record packet only when alt_rssi is positive */
+       if (alt_rssi > 0) {
+               antcomb->total_pkt_count++;
+               antcomb->main_total_rssi += main_rssi;
+               antcomb->alt_total_rssi  += alt_rssi;
+               if (main_ant_conf == rx_ant_conf)
+                       antcomb->main_recv_cnt++;
+               else
+                       antcomb->alt_recv_cnt++;
+       }
+
+       /* Short scan check */
+       if (antcomb->scan && antcomb->alt_good) {
+               if (time_after(jiffies, antcomb->scan_start_time +
+                   msecs_to_jiffies(ATH_ANT_DIV_COMB_SHORT_SCAN_INTR)))
+                       short_scan = true;
+               else
+                       if (antcomb->total_pkt_count ==
+                           ATH_ANT_DIV_COMB_SHORT_SCAN_PKTCOUNT) {
+                               alt_ratio = ((antcomb->alt_recv_cnt * 100) /
+                                           antcomb->total_pkt_count);
+                               if (alt_ratio < ATH_ANT_DIV_COMB_ALT_ANT_RATIO)
+                                       short_scan = true;
+                       }
+       }
+
+       if (((antcomb->total_pkt_count < ATH_ANT_DIV_COMB_MAX_PKTCOUNT) ||
+           rs->rs_moreaggr) && !short_scan)
+               return;
+
+       if (antcomb->total_pkt_count) {
+               alt_ratio = ((antcomb->alt_recv_cnt * 100) /
+                            antcomb->total_pkt_count);
+               main_rssi_avg = (antcomb->main_total_rssi /
+                                antcomb->total_pkt_count);
+               alt_rssi_avg = (antcomb->alt_total_rssi /
+                                antcomb->total_pkt_count);
+       }
+
+
+       ath9k_hw_antdiv_comb_conf_get(sc->sc_ah, &div_ant_conf);
+       curr_alt_set = div_ant_conf.alt_lna_conf;
+       curr_main_set = div_ant_conf.main_lna_conf;
+       curr_bias = div_ant_conf.fast_div_bias;
+
+       antcomb->count++;
+
+       if (antcomb->count == ATH_ANT_DIV_COMB_MAX_COUNT) {
+               if (alt_ratio > ATH_ANT_DIV_COMB_ALT_ANT_RATIO) {
+                       ath_lnaconf_alt_good_scan(antcomb, div_ant_conf,
+                                                 main_rssi_avg);
+                       antcomb->alt_good = true;
+               } else {
+                       antcomb->alt_good = false;
+               }
+
+               antcomb->count = 0;
+               antcomb->scan = true;
+               antcomb->scan_not_start = true;
+       }
+
+       if (!antcomb->scan) {
+               if (alt_ratio > ATH_ANT_DIV_COMB_ALT_ANT_RATIO) {
+                       if (curr_alt_set == ATH_ANT_DIV_COMB_LNA2) {
+                               /* Switch main and alt LNA */
+                               div_ant_conf.main_lna_conf =
+                                               ATH_ANT_DIV_COMB_LNA2;
+                               div_ant_conf.alt_lna_conf  =
+                                               ATH_ANT_DIV_COMB_LNA1;
+                       } else if (curr_alt_set == ATH_ANT_DIV_COMB_LNA1) {
+                               div_ant_conf.main_lna_conf =
+                                               ATH_ANT_DIV_COMB_LNA1;
+                               div_ant_conf.alt_lna_conf  =
+                                               ATH_ANT_DIV_COMB_LNA2;
+                       }
+
+                       goto div_comb_done;
+               } else if ((curr_alt_set != ATH_ANT_DIV_COMB_LNA1) &&
+                          (curr_alt_set != ATH_ANT_DIV_COMB_LNA2)) {
+                       /* Set alt to another LNA */
+                       if (curr_main_set == ATH_ANT_DIV_COMB_LNA2)
+                               div_ant_conf.alt_lna_conf =
+                                               ATH_ANT_DIV_COMB_LNA1;
+                       else if (curr_main_set == ATH_ANT_DIV_COMB_LNA1)
+                               div_ant_conf.alt_lna_conf =
+                                               ATH_ANT_DIV_COMB_LNA2;
+
+                       goto div_comb_done;
+               }
+
+               if ((alt_rssi_avg < (main_rssi_avg +
+                   ATH_ANT_DIV_COMB_LNA1_LNA2_DELTA)))
+                       goto div_comb_done;
+       }
+
+       if (!antcomb->scan_not_start) {
+               switch (curr_alt_set) {
+               case ATH_ANT_DIV_COMB_LNA2:
+                       antcomb->rssi_lna2 = alt_rssi_avg;
+                       antcomb->rssi_lna1 = main_rssi_avg;
+                       antcomb->scan = true;
+                       /* set to A+B */
+                       div_ant_conf.main_lna_conf =
+                               ATH_ANT_DIV_COMB_LNA1;
+                       div_ant_conf.alt_lna_conf  =
+                               ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
+                       break;
+               case ATH_ANT_DIV_COMB_LNA1:
+                       antcomb->rssi_lna1 = alt_rssi_avg;
+                       antcomb->rssi_lna2 = main_rssi_avg;
+                       antcomb->scan = true;
+                       /* set to A+B */
+                       div_ant_conf.main_lna_conf = ATH_ANT_DIV_COMB_LNA2;
+                       div_ant_conf.alt_lna_conf  =
+                               ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
+                       break;
+               case ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2:
+                       antcomb->rssi_add = alt_rssi_avg;
+                       antcomb->scan = true;
+                       /* set to A-B */
+                       div_ant_conf.alt_lna_conf =
+                               ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
+                       break;
+               case ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2:
+                       antcomb->rssi_sub = alt_rssi_avg;
+                       antcomb->scan = false;
+                       if (antcomb->rssi_lna2 >
+                           (antcomb->rssi_lna1 +
+                           ATH_ANT_DIV_COMB_LNA1_LNA2_SWITCH_DELTA)) {
+                               /* use LNA2 as main LNA */
+                               if ((antcomb->rssi_add > antcomb->rssi_lna1) &&
+                                   (antcomb->rssi_add > antcomb->rssi_sub)) {
+                                       /* set to A+B */
+                                       div_ant_conf.main_lna_conf =
+                                               ATH_ANT_DIV_COMB_LNA2;
+                                       div_ant_conf.alt_lna_conf  =
+                                               ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
+                               } else if (antcomb->rssi_sub >
+                                          antcomb->rssi_lna1) {
+                                       /* set to A-B */
+                                       div_ant_conf.main_lna_conf =
+                                               ATH_ANT_DIV_COMB_LNA2;
+                                       div_ant_conf.alt_lna_conf =
+                                               ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
+                               } else {
+                                       /* set to LNA1 */
+                                       div_ant_conf.main_lna_conf =
+                                               ATH_ANT_DIV_COMB_LNA2;
+                                       div_ant_conf.alt_lna_conf =
+                                               ATH_ANT_DIV_COMB_LNA1;
+                               }
+                       } else {
+                               /* use LNA1 as main LNA */
+                               if ((antcomb->rssi_add > antcomb->rssi_lna2) &&
+                                   (antcomb->rssi_add > antcomb->rssi_sub)) {
+                                       /* set to A+B */
+                                       div_ant_conf.main_lna_conf =
+                                               ATH_ANT_DIV_COMB_LNA1;
+                                       div_ant_conf.alt_lna_conf  =
+                                               ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
+                               } else if (antcomb->rssi_sub >
+                                          antcomb->rssi_lna1) {
+                                       /* set to A-B */
+                                       div_ant_conf.main_lna_conf =
+                                               ATH_ANT_DIV_COMB_LNA1;
+                                       div_ant_conf.alt_lna_conf =
+                                               ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
+                               } else {
+                                       /* set to LNA2 */
+                                       div_ant_conf.main_lna_conf =
+                                               ATH_ANT_DIV_COMB_LNA1;
+                                       div_ant_conf.alt_lna_conf =
+                                               ATH_ANT_DIV_COMB_LNA2;
+                               }
+                       }
+                       break;
+               default:
+                       break;
+               }
+       } else {
+               if (!antcomb->alt_good) {
+                       antcomb->scan_not_start = false;
+                       /* Set alt to another LNA */
+                       if (curr_main_set == ATH_ANT_DIV_COMB_LNA2) {
+                               div_ant_conf.main_lna_conf =
+                                               ATH_ANT_DIV_COMB_LNA2;
+                               div_ant_conf.alt_lna_conf =
+                                               ATH_ANT_DIV_COMB_LNA1;
+                       } else if (curr_main_set == ATH_ANT_DIV_COMB_LNA1) {
+                               div_ant_conf.main_lna_conf =
+                                               ATH_ANT_DIV_COMB_LNA1;
+                               div_ant_conf.alt_lna_conf =
+                                               ATH_ANT_DIV_COMB_LNA2;
+                       }
+                       goto div_comb_done;
+               }
+       }
+
+       ath_select_ant_div_from_quick_scan(antcomb, &div_ant_conf,
+                                          main_rssi_avg, alt_rssi_avg,
+                                          alt_ratio);
+
+       antcomb->quick_scan_cnt++;
+
+div_comb_done:
+       ath_ant_div_conf_fast_divbias(&div_ant_conf);
+
+       ath9k_hw_antdiv_comb_conf_set(sc->sc_ah, &div_ant_conf);
+
+       antcomb->scan_start_time = jiffies;
+       antcomb->total_pkt_count = 0;
+       antcomb->main_total_rssi = 0;
+       antcomb->alt_total_rssi = 0;
+       antcomb->main_recv_cnt = 0;
+       antcomb->alt_recv_cnt = 0;
+}
 
 int ath_rx_tasklet(struct ath_softc *sc, int flush, bool hp)
 {
@@ -842,6 +1637,9 @@ int ath_rx_tasklet(struct ath_softc *sc, int flush, bool hp)
        enum ath9k_rx_qtype qtype;
        bool edma = !!(ah->caps.hw_caps & ATH9K_HW_CAP_EDMA);
        int dma_type;
+       u8 rx_status_len = ah->caps.rx_status_len;
+       u64 tsf = 0;
+       u32 tsf_lower = 0;
 
        if (edma)
                dma_type = DMA_BIDIRECTIONAL;
@@ -851,6 +1649,9 @@ int ath_rx_tasklet(struct ath_softc *sc, int flush, bool hp)
        qtype = hp ? ATH9K_RX_QUEUE_HP : ATH9K_RX_QUEUE_LP;
        spin_lock_bh(&sc->rx.rxbuflock);
 
+       tsf = ath9k_hw_gettsf64(ah);
+       tsf_lower = tsf & 0xffffffff;
+
        do {
                /* If handling rx interrupt and flush is in progress => exit */
                if ((sc->sc_flags & SC_OP_RXFLUSH) && (flush == 0))
@@ -869,7 +1670,7 @@ int ath_rx_tasklet(struct ath_softc *sc, int flush, bool hp)
                if (!skb)
                        continue;
 
-               hdr = (struct ieee80211_hdr *) skb->data;
+               hdr = (struct ieee80211_hdr *) (skb->data + rx_status_len);
                rxs =  IEEE80211_SKB_RXCB(skb);
 
                hw = ath_get_virt_hw(sc, hdr);
@@ -883,11 +1684,20 @@ int ath_rx_tasklet(struct ath_softc *sc, int flush, bool hp)
                if (flush)
                        goto requeue;
 
-               retval = ath9k_cmn_rx_skb_preprocess(common, hw, skb, &rs,
-                                                    rxs, &decrypt_error);
+               retval = ath9k_rx_skb_preprocess(common, hw, hdr, &rs,
+                                                rxs, &decrypt_error);
                if (retval)
                        goto requeue;
 
+               rxs->mactime = (tsf & ~0xffffffffULL) | rs.rs_tstamp;
+               if (rs.rs_tstamp > tsf_lower &&
+                   unlikely(rs.rs_tstamp - tsf_lower > 0x10000000))
+                       rxs->mactime -= 0x100000000ULL;
+
+               if (rs.rs_tstamp < tsf_lower &&
+                   unlikely(tsf_lower - rs.rs_tstamp > 0x10000000))
+                       rxs->mactime += 0x100000000ULL;
+
                /* Ensure we always have an skb to requeue once we are done
                 * processing the current buffer's skb */
                requeue_skb = ath_rxbuf_alloc(common, common->rx_bufsize, GFP_ATOMIC);
@@ -908,8 +1718,8 @@ int ath_rx_tasklet(struct ath_softc *sc, int flush, bool hp)
                if (ah->caps.rx_status_len)
                        skb_pull(skb, ah->caps.rx_status_len);
 
-               ath9k_cmn_rx_skb_postprocess(common, skb, &rs,
-                                            rxs, decrypt_error);
+               ath9k_rx_skb_postprocess(common, skb, &rs,
+                                        rxs, decrypt_error);
 
                /* We will now give hardware our shiny new allocated skb */
                bf->bf_mpdu = requeue_skb;
@@ -944,6 +1754,9 @@ int ath_rx_tasklet(struct ath_softc *sc, int flush, bool hp)
                                              PS_WAIT_FOR_PSPOLL_DATA))))
                        ath_rx_ps(sc, skb);
 
+               if (ah->caps.hw_caps & ATH9K_HW_CAP_ANT_DIV_COMB)
+                       ath_ant_comb_scan(sc, &rs);
+
                ath_rx_send_to_mac80211(hw, sc, skb, rxs);
 
 requeue: