3 files changed, 40 insertions, 17 deletions

diff --git a/drivers/net/wireless/ath9k/ath9k.h b/drivers/net/wireless/ath9k/ath9k.h
index 0769a252dfe1..4c1da716e6d8 100644
--- a/drivers/net/wireless/ath9k/ath9k.h
+++ b/drivers/net/wireless/ath9k/ath9k.h
@@ -542,22 +542,23 @@ struct ath_rfkill {
 #define ATH_RSSI_DUMMY_MARKER   0x127
 #define ATH_RATE_DUMMY_MARKER   0
 
-#define SC_OP_INVALID           BIT(0)
-#define SC_OP_BEACONS           BIT(1)
-#define SC_OP_RXAGGR            BIT(2)
-#define SC_OP_TXAGGR            BIT(3)
-#define SC_OP_CHAINMASK_UPDATE  BIT(4)
-#define SC_OP_FULL_RESET        BIT(5)
-#define SC_OP_PREAMBLE_SHORT    BIT(6)
-#define SC_OP_PROTECT_ENABLE    BIT(7)
-#define SC_OP_RXFLUSH           BIT(8)
-#define SC_OP_LED_ASSOCIATED    BIT(9)
-#define SC_OP_RFKILL_REGISTERED BIT(10)
-#define SC_OP_RFKILL_SW_BLOCKED BIT(11)
-#define SC_OP_RFKILL_HW_BLOCKED BIT(12)
-#define SC_OP_WAIT_FOR_BEACON   BIT(13)
-#define SC_OP_LED_ON            BIT(14)
-#define SC_OP_SCANNING          BIT(15)
+#define SC_OP_INVALID           BIT(0)
+#define SC_OP_BEACONS           BIT(1)
+#define SC_OP_RXAGGR            BIT(2)
+#define SC_OP_TXAGGR            BIT(3)
+#define SC_OP_CHAINMASK_UPDATE  BIT(4)
+#define SC_OP_FULL_RESET        BIT(5)
+#define SC_OP_PREAMBLE_SHORT    BIT(6)
+#define SC_OP_PROTECT_ENABLE    BIT(7)
+#define SC_OP_RXFLUSH           BIT(8)
+#define SC_OP_LED_ASSOCIATED    BIT(9)
+#define SC_OP_RFKILL_REGISTERED BIT(10)
+#define SC_OP_RFKILL_SW_BLOCKED BIT(11)
+#define SC_OP_RFKILL_HW_BLOCKED BIT(12)
+#define SC_OP_WAIT_FOR_BEACON   BIT(13)
+#define SC_OP_LED_ON            BIT(14)
+#define SC_OP_SCANNING          BIT(15)
+#define SC_OP_TSF_RESET         BIT(16)
 
 struct ath_bus_ops {
         void            (*read_cachesize)(struct ath_softc *sc, int *csz);
diff --git a/drivers/net/wireless/ath9k/beacon.c b/drivers/net/wireless/ath9k/beacon.c
index 74916431f575..d1365726d2f3 100644
--- a/drivers/net/wireless/ath9k/beacon.c
+++ b/drivers/net/wireless/ath9k/beacon.c
@@ -510,6 +510,11 @@ static void ath_beacon_config_ap(struct ath_softc *sc,
 {
         u32 nexttbtt, intval;
 
+        /* Configure the timers only when the TSF has to be reset */
+
+        if (!(sc->sc_flags & SC_OP_TSF_RESET))
+                return;
+
         /* NB: the beacon interval is kept internally in TU's */
         intval = conf->beacon_interval & ATH9K_BEACON_PERIOD;
         intval /= ATH_BCBUF;    /* for staggered beacons */
@@ -530,6 +535,11 @@ static void ath_beacon_config_ap(struct ath_softc *sc,
         ath9k_hw_beaconinit(sc->sc_ah, nexttbtt, intval);
         sc->beacon.bmisscnt = 0;
         ath9k_hw_set_interrupts(sc->sc_ah, sc->imask);
+
+        /* Clear the reset TSF flag, so that subsequent beacon updation
+           will not reset the HW TSF. */
+
+        sc->sc_flags &= ~SC_OP_TSF_RESET;
 }
 
 /*
diff --git a/drivers/net/wireless/ath9k/main.c b/drivers/net/wireless/ath9k/main.c
index 9e8f954877c9..a25dcf949f36 100644
--- a/drivers/net/wireless/ath9k/main.c
+++ b/drivers/net/wireless/ath9k/main.c
@@ -2168,8 +2168,10 @@ static int ath9k_add_interface(struct ieee80211_hw *hw,
         avp->av_opmode = ic_opmode;
         avp->av_bslot = -1;
 
-        if (ic_opmode == NL80211_IFTYPE_AP)
+        if (ic_opmode == NL80211_IFTYPE_AP) {
                 ath9k_hw_set_tsfadjust(sc->sc_ah, 1);
+                sc->sc_flags |= SC_OP_TSF_RESET;
+        }
 
         sc->vifs[0] = conf->vif;
         sc->nvifs++;
@@ -2291,6 +2293,16 @@ static int ath9k_config(struct ieee80211_hw *hw, u32 changed)
         if (changed & IEEE80211_CONF_CHANGE_POWER)
                 sc->config.txpowlimit = 2 * conf->power_level;
 
+        /*
+         * The HW TSF has to be reset when the beacon interval changes.
+         * We set the flag here, and ath_beacon_config_ap() would take this
+         * into account when it gets called through the subsequent
+         * config_interface() call - with IFCC_BEACON in the changed field.
+         */
+
+        if (changed & IEEE80211_CONF_CHANGE_BEACON_INTERVAL)
+                sc->sc_flags |= SC_OP_TSF_RESET;
+
         mutex_unlock(&sc->mutex);
 
         return 0;