ath9k: stomp audio profiles on weak signal strength

On lower WLAN signal strength, WLAN downlink traffic might suffer
from retransmissions. At the mean time, playing SCO/A2DP profiles
is affecting WLAN stability. In such scenario, by stomping SCO/A2DP
BT traffic completely for a BTCOEX period, gives WLAN traffic an
oppertunity to recover PHY rate. It also improves WLAN stability at
lower RSSI without sacificing BT traffic.

Signed-off-by: Rajkumar Manoharan <rmanohar@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

5 files changed, 25 insertions, 1 deletions

diff --git a/drivers/net/wireless/ath/ath9k/ath9k.h b/drivers/net/wireless/ath/ath9k/ath9k.h
index 9a93d2bb8f66..04fa5f350e8c 100644
--- a/drivers/net/wireless/ath/ath9k/ath9k.h
+++ b/drivers/net/wireless/ath/ath9k/ath9k.h
@@ -488,6 +488,7 @@ struct ath_btcoex {
         int rssi_count;
         struct ath_gen_timer *no_stomp_timer; /* Timer for no BT stomping */
         struct ath_mci_profile mci;
+        u8 stomp_audio;
 };
 
 #ifdef CONFIG_ATH9K_BTCOEX_SUPPORT
diff --git a/drivers/net/wireless/ath/ath9k/btcoex.c b/drivers/net/wireless/ath/ath9k/btcoex.c
index c90e9bc4b026..9963b0bf9f72 100644
--- a/drivers/net/wireless/ath/ath9k/btcoex.c
+++ b/drivers/net/wireless/ath/ath9k/btcoex.c
@@ -49,6 +49,7 @@ static const u32 mci_wlan_weights[ATH_BTCOEX_STOMP_MAX]
         { 0x01017d01, 0x3b3b3b01, 0x3b3b3b01, 0x3b3b3b3b }, /* STOMP_LOW */
         { 0x01017d01, 0x01010101, 0x01010101, 0x01010101 }, /* STOMP_NONE */
         { 0x01017d01, 0x013b0101, 0x3b3b0101, 0x3b3b013b }, /* STOMP_LOW_FTP */
+        { 0xffffff01, 0xffffffff, 0xffffff01, 0xffffffff }, /* STOMP_AUDIO */
 };
 
 void ath9k_hw_init_btcoex_hw(struct ath_hw *ah, int qnum)
diff --git a/drivers/net/wireless/ath/ath9k/btcoex.h b/drivers/net/wireless/ath/ath9k/btcoex.h
index 2f84ab273d0c..6de26ea5d5fa 100644
--- a/drivers/net/wireless/ath/ath9k/btcoex.h
+++ b/drivers/net/wireless/ath/ath9k/btcoex.h
@@ -50,6 +50,7 @@ enum ath_stomp_type {
         ATH_BTCOEX_STOMP_LOW,
         ATH_BTCOEX_STOMP_NONE,
         ATH_BTCOEX_STOMP_LOW_FTP,
+        ATH_BTCOEX_STOMP_AUDIO,
         ATH_BTCOEX_STOMP_MAX
 };
 
diff --git a/drivers/net/wireless/ath/ath9k/gpio.c b/drivers/net/wireless/ath/ath9k/gpio.c
index 4236df8ffe67..7b39cc14662d 100644
--- a/drivers/net/wireless/ath/ath9k/gpio.c
+++ b/drivers/net/wireless/ath/ath9k/gpio.c
@@ -247,6 +247,9 @@ static void ath_btcoex_period_timer(unsigned long data)
                         stomp_type = ATH_BTCOEX_STOMP_ALL;
                         timer_period = btcoex->btscan_no_stomp;
                 }
+        } else if (btcoex->stomp_audio >= 5) {
+                stomp_type = ATH_BTCOEX_STOMP_AUDIO;
+                btcoex->stomp_audio = 0;
         }
 
         ath9k_hw_btcoex_bt_stomp(ah, stomp_type);
@@ -295,7 +298,7 @@ static void ath_btcoex_no_stomp_timer(void *arg)
             (!(ah->caps.hw_caps & ATH9K_HW_CAP_MCI) &&
              test_bit(BT_OP_SCAN, &btcoex->op_flags)))
                 ath9k_hw_btcoex_bt_stomp(ah, ATH_BTCOEX_STOMP_NONE);
-         else if (btcoex->bt_stomp_type == ATH_BTCOEX_STOMP_ALL)
+        else if (btcoex->bt_stomp_type == ATH_BTCOEX_STOMP_ALL)
                 ath9k_hw_btcoex_bt_stomp(ah, ATH_BTCOEX_STOMP_LOW);
 
         ath9k_hw_btcoex_enable(ah);
diff --git a/drivers/net/wireless/ath/ath9k/mci.c b/drivers/net/wireless/ath/ath9k/mci.c
index ece192d77355..706378ea3ba2 100644
--- a/drivers/net/wireless/ath/ath9k/mci.c
+++ b/drivers/net/wireless/ath/ath9k/mci.c
@@ -729,12 +729,30 @@ void ath9k_mci_set_txpower(struct ath_softc *sc, bool setchannel,
                 ath9k_hw_set_txpowerlimit(ah, sc->config.txpowlimit, false);
 }
 
+static void ath9k_mci_stomp_audio(struct ath_softc *sc)
+{
+        struct ath_hw *ah = sc->sc_ah;
+        struct ath_btcoex *btcoex = &sc->btcoex;
+        struct ath_mci_profile *mci = &btcoex->mci;
+
+        if (!mci->num_sco && !mci->num_a2dp)
+                return;
+
+        if (ah->stats.avgbrssi > 25) {
+                btcoex->stomp_audio = 0;
+                return;
+        }
+
+        btcoex->stomp_audio++;
+}
 void ath9k_mci_update_rssi(struct ath_softc *sc)
 {
         struct ath_hw *ah = sc->sc_ah;
         struct ath_btcoex *btcoex = &sc->btcoex;
         struct ath9k_hw_mci *mci_hw = &sc->sc_ah->btcoex_hw.mci;
 
+        ath9k_mci_stomp_audio(sc);
+
         if (!(mci_hw->config & ATH_MCI_CONFIG_CONCUR_TX))
                 return;