Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wirel...

[cascardo/linux.git] / net / mac80211 / rc80211_minstrel_ht.c

diff --git a/net/mac80211/rc80211_minstrel_ht.c b/net/mac80211/rc80211_minstrel_ht.c
index 8212a8b..333b511 100644 (file)
--- a/net/mac80211/rc80211_minstrel_ht.c
+++ b/net/mac80211/rc80211_minstrel_ht.c
@@ -259,7 +259,7 @@ minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi)
                }
        }
 
-       /* try to sample up to half of the availble rates during each interval */
+       /* try to sample up to half of the available rates during each interval */
        mi->sample_count *= 4;
 
        cur_prob = 0;
@@ -464,6 +464,7 @@ minstrel_calc_retransmit(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
        const struct mcs_group *group;
        unsigned int tx_time, tx_time_rtscts, tx_time_data;
        unsigned int cw = mp->cw_min;
+       unsigned int ctime = 0;
        unsigned int t_slot = 9; /* FIXME */
        unsigned int ampdu_len = MINSTREL_TRUNC(mi->avg_ampdu_len);
 
@@ -480,13 +481,27 @@ minstrel_calc_retransmit(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
 
        group = &minstrel_mcs_groups[index / MCS_GROUP_RATES];
        tx_time_data = group->duration[index % MCS_GROUP_RATES] * ampdu_len;
-       tx_time = 2 * (t_slot + mi->overhead + tx_time_data);
-       tx_time_rtscts = 2 * (t_slot + mi->overhead_rtscts + tx_time_data);
+
+       /* Contention time for first 2 tries */
+       ctime = (t_slot * cw) >> 1;
+       cw = min((cw << 1) | 1, mp->cw_max);
+       ctime += (t_slot * cw) >> 1;
+       cw = min((cw << 1) | 1, mp->cw_max);
+
+       /* Total TX time for data and Contention after first 2 tries */
+       tx_time = ctime + 2 * (mi->overhead + tx_time_data);
+       tx_time_rtscts = ctime + 2 * (mi->overhead_rtscts + tx_time_data);
+
+       /* See how many more tries we can fit inside segment size */
        do {
-               cw = (cw << 1) | 1;
-               cw = min(cw, mp->cw_max);
-               tx_time += cw + t_slot + mi->overhead;
-               tx_time_rtscts += cw + t_slot + mi->overhead_rtscts;
+               /* Contention time for this try */
+               ctime = (t_slot * cw) >> 1;
+               cw = min((cw << 1) | 1, mp->cw_max);
+
+               /* Total TX time after this try */
+               tx_time += ctime + mi->overhead + tx_time_data;
+               tx_time_rtscts += ctime + mi->overhead_rtscts + tx_time_data;
+
                if (tx_time_rtscts < mp->segment_size)
                        mr->retry_count_rtscts++;
        } while ((tx_time < mp->segment_size) &&
@@ -659,18 +674,14 @@ minstrel_ht_update_caps(void *priv, struct ieee80211_supported_band *sband,
        struct ieee80211_mcs_info *mcs = &sta->ht_cap.mcs;
        struct ieee80211_local *local = hw_to_local(mp->hw);
        u16 sta_cap = sta->ht_cap.cap;
+       int n_supported = 0;
        int ack_dur;
        int stbc;
        int i;
 
        /* fall back to the old minstrel for legacy stations */
-       if (!sta->ht_cap.ht_supported) {
-               msp->is_ht = false;
-               memset(&msp->legacy, 0, sizeof(msp->legacy));
-               msp->legacy.r = msp->ratelist;
-               msp->legacy.sample_table = msp->sample_table;
-               return mac80211_minstrel.rate_init(priv, sband, sta, &msp->legacy);
-       }
+       if (!sta->ht_cap.ht_supported)
+               goto use_legacy;
 
        BUILD_BUG_ON(ARRAY_SIZE(minstrel_mcs_groups) !=
                MINSTREL_MAX_STREAMS * MINSTREL_STREAM_GROUPS);
@@ -725,7 +736,22 @@ minstrel_ht_update_caps(void *priv, struct ieee80211_supported_band *sband,
 
                mi->groups[i].supported =
                        mcs->rx_mask[minstrel_mcs_groups[i].streams - 1];
+
+               if (mi->groups[i].supported)
+                       n_supported++;
        }
+
+       if (!n_supported)
+               goto use_legacy;
+
+       return;
+
+use_legacy:
+       msp->is_ht = false;
+       memset(&msp->legacy, 0, sizeof(msp->legacy));
+       msp->legacy.r = msp->ratelist;
+       msp->legacy.sample_table = msp->sample_table;
+       return mac80211_minstrel.rate_init(priv, sband, sta, &msp->legacy);
 }
 
 static void