ath9k: Disable TX STBC for AR9485

Signed-off-by: Vasanthakumar Thiagarajan <vasanth@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/ath/ath9k/init.c b/drivers/net/wireless/ath/ath9k/init.c
index 5987ed1..bd451c2 100644
--- a/drivers/net/wireless/ath/ath9k/init.c
+++ b/drivers/net/wireless/ath/ath9k/init.c
@@ -210,7 +210,9 @@
 	ht_info->ampdu_factor = IEEE80211_HT_MAX_AMPDU_64K;
 	ht_info->ampdu_density = IEEE80211_HT_MPDU_DENSITY_8;
 
-	if (AR_SREV_9300_20_OR_LATER(ah))
+	if (AR_SREV_9485(ah))
+		max_streams = 1;
+	else if (AR_SREV_9300_20_OR_LATER(ah))
 		max_streams = 3;
 	else
 		max_streams = 2;