ath9k: Fix bug in rate control capability registration

Dual stream capability must be registered only when the
hardware supports it.

Signed-off-by: Sujith <Sujith.Manoharan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 3 insertions, 1 deletions

diff --git a/drivers/net/wireless/ath9k/rc.c b/drivers/net/wireless/ath9k/rc.c
index 46172b5f492c..8e1528d487b5 100644
--- a/drivers/net/wireless/ath9k/rc.c
+++ b/drivers/net/wireless/ath9k/rc.c
@@ -1358,7 +1358,9 @@ static void ath_rc_init(struct ath_softc *sc,
         }
 
         if (sta->ht_cap.ht_supported) {
-                ath_rc_priv->ht_cap = (WLAN_RC_HT_FLAG | WLAN_RC_DS_FLAG);
+                ath_rc_priv->ht_cap = WLAN_RC_HT_FLAG;
+                if (sc->sc_tx_chainmask != 1)
+                        ath_rc_priv->ht_cap |= WLAN_RC_DS_FLAG;
                 if (sta->ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40)
                         ath_rc_priv->ht_cap |= WLAN_RC_40_FLAG;
                 if (sta->ht_cap.cap & IEEE80211_HT_CAP_SGI_40)