ath9k: fix max phy rate at rate control init

BugLink: http://bugs.launchpad.net/bugs/913373

commit 10636bc2d60942254bda149827b922c41f4cb4af upstream.

The stations always chooses 1Mbps for all trasmitting frames,
whenever the AP is configured to lock the supported rates.
As the max phy rate is always set with the 4th from highest phy rate,
this assumption might be wrong if we have less than that. Fix that.

Cc: Paul Stewart <pstew@google.com>
Reported-by: Ajay Gummalla <agummalla@google.com>
Signed-off-by: Rajkumar Manoharan <rmanohar@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Brad Figg <brad.figg@canonical.com>

1 files changed, 3 insertions, 1 deletions

diff --git a/drivers/net/wireless/ath/ath9k/rc.c b/drivers/net/wireless/ath/ath9k/rc.c
index ba7f36ab0a7..ea35843dd38 100644
--- a/drivers/net/wireless/ath/ath9k/rc.c
+++ b/drivers/net/wireless/ath/ath9k/rc.c
@@ -1252,7 +1252,9 @@ static void ath_rc_init(struct ath_softc *sc,
 
         ath_rc_priv->max_valid_rate = k;
         ath_rc_sort_validrates(rate_table, ath_rc_priv);
-        ath_rc_priv->rate_max_phy = ath_rc_priv->valid_rate_index[k-4];
+        ath_rc_priv->rate_max_phy = (k > 4) ?
+                                        ath_rc_priv->valid_rate_index[k-4] :
+                                        ath_rc_priv->valid_rate_index[k-1];
         ath_rc_priv->rate_table = rate_table;
 
         ath_dbg(common, ATH_DBG_CONFIG,