mac80211: Update the station failed frames average when minstrel is used.

The fail_avg value is used to compute the mesh metric, and was only being set
by the pid rate control module. This fixes the mesh path selection mechanism
for cards that use mistrel for rate control.
Signed-off-by: Javier Cardona <javier@cozybit.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

net/mac80211/rc80211_minstrel.c

@@ -155,12 +155,16 @@ minstrel_tx_status(void *priv, struct ieee80211_supported_band *sband,
 		   struct sk_buff *skb)
 {
 	struct minstrel_sta_info *mi = priv_sta;
+	struct minstrel_priv *mp = (struct minstrel_priv *)priv;
 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 	struct ieee80211_tx_rate *ar = info->status.rates;
+	struct ieee80211_local *local = hw_to_local(mp->hw);
+	struct sta_info *si;
 	int i, ndx;
 	int success;
 
 	success = !!(info->flags & IEEE80211_TX_STAT_ACK);
+	si = sta_info_get(local, sta->addr);
 
 	for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
 		if (ar[i].idx < 0)
@@ -172,8 +176,12 @@ minstrel_tx_status(void *priv, struct ieee80211_supported_band *sband,
 
 		mi->r[ndx].attempts += ar[i].count;
 
-		if ((i != IEEE80211_TX_MAX_RATES - 1) && (ar[i + 1].idx < 0))
+		if ((i != IEEE80211_TX_MAX_RATES - 1) && (ar[i + 1].idx < 0)) {
 			mi->r[ndx].success += success;
+			if (si)
+				si->fail_avg = (18050 - mi->r[ndx].probability)
+					/ 180;
+		}
 	}
 
 	if ((info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE) && (i >= 0))