ath10k: improve 11b coex

Some firmware revisions need peer phymode to be
specified as MODE_11B when associating as station
to a 11b AP. Otherwise they can starve other
stations.

Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>

diff --git a/drivers/net/wireless/ath/ath10k/mac.c b/drivers/net/wireless/ath/ath10k/mac.c
index fe61201..950322d 100644 (file)
--- a/drivers/net/wireless/ath/ath10k/mac.c
+++ b/drivers/net/wireless/ath/ath10k/mac.c
@@ -1416,6 +1416,12 @@ static void ath10k_peer_assoc_h_qos(struct ath10k *ar,
        }
 }
 
+static bool ath10k_mac_sta_has_11g_rates(struct ieee80211_sta *sta)
+{
+       /* First 4 rates in ath10k_rates are CCK (11b) rates. */
+       return sta->supp_rates[IEEE80211_BAND_2GHZ] >> 4;
+}
+
 static void ath10k_peer_assoc_h_phymode(struct ath10k *ar,
                                        struct ieee80211_vif *vif,
                                        struct ieee80211_sta *sta,
@@ -1430,8 +1436,10 @@ static void ath10k_peer_assoc_h_phymode(struct ath10k *ar,
                                phymode = MODE_11NG_HT40;
                        else
                                phymode = MODE_11NG_HT20;
-               } else {
+               } else if (ath10k_mac_sta_has_11g_rates(sta)) {
                        phymode = MODE_11G;
+               } else {
+                       phymode = MODE_11B;
                }
 
                break;
@@ -4724,6 +4732,9 @@ static const struct ieee80211_channel ath10k_5ghz_channels[] = {
        CHAN5G(165, 5825, 0),
 };
 
+/* Note: Be careful if you re-order these. There is code which depends on this
+ * ordering.
+ */
 static struct ieee80211_rate ath10k_rates[] = {
        /* CCK */
        RATETAB_ENT(10,  0x82, 0),