ath9k: Fix work handling

* Currently, there is no synchronization between the reset
  work and the tx-poll work. Fix this and make sure that we
  bail out properly if a reset work is in progress.

* Cleanup the PLL WAR and enable it for AR9340 too and
  use a helper for restarting work/timers after a reset.

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

3 files changed, 37 insertions, 19 deletions

diff --git a/drivers/net/wireless/ath/ath9k/ath9k.h b/drivers/net/wireless/ath/ath9k/ath9k.h
index d804416092ce..2faa181d8fcf 100644
--- a/drivers/net/wireless/ath/ath9k/ath9k.h
+++ b/drivers/net/wireless/ath/ath9k/ath9k.h
@@ -431,6 +431,7 @@ void ath9k_set_beaconing_status(struct ath_softc *sc, bool status);
 #define ATH_RESTART_CALINTERVAL   1200000 /* 20 minutes */
 
 #define ATH_PAPRD_TIMEOUT       100 /* msecs */
+#define ATH_PLL_WORK_INTERVAL   100
 
 void ath_tx_complete_poll_work(struct work_struct *work);
 void ath_reset_work(struct work_struct *work);
diff --git a/drivers/net/wireless/ath/ath9k/link.c b/drivers/net/wireless/ath/ath9k/link.c
index 7368b9630b99..89b38a9ab7c5 100644
--- a/drivers/net/wireless/ath/ath9k/link.c
+++ b/drivers/net/wireless/ath/ath9k/link.c
@@ -52,6 +52,7 @@ void ath_tx_complete_poll_work(struct work_struct *work)
                         "tx hung, resetting the chip\n");
                 RESET_STAT_INC(sc, RESET_TYPE_TX_HANG);
                 ieee80211_queue_work(sc->hw, &sc->hw_reset_work);
+                return;
         }
 
         ieee80211_queue_delayed_work(sc->hw, &sc->tx_complete_work,
@@ -107,9 +108,9 @@ out:
 }
 
 /*
- * PLL-WAR for AR9485.
+ * PLL-WAR for AR9485/AR9340
  */
-static void ath_hw_pll_rx_hang_check(struct ath_softc *sc, u32 pll_sqsum)
+static bool ath_hw_pll_rx_hang_check(struct ath_softc *sc, u32 pll_sqsum)
 {
         static int count;
         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
@@ -117,29 +118,33 @@ static void ath_hw_pll_rx_hang_check(struct ath_softc *sc, u32 pll_sqsum)
         if (pll_sqsum >= 0x40000) {
                 count++;
                 if (count == 3) {
-                        /* Rx is hung for more than 500ms. Reset it */
-                        ath_dbg(common, RESET, "Possible RX hang, resetting\n");
+                        ath_dbg(common, RESET, "PLL WAR, resetting the chip\n");
                         RESET_STAT_INC(sc, RESET_TYPE_PLL_HANG);
                         ieee80211_queue_work(sc->hw, &sc->hw_reset_work);
                         count = 0;
+                        return true;
                 }
-        } else
+        } else {
                 count = 0;
+        }
+
+        return false;
 }
 
 void ath_hw_pll_work(struct work_struct *work)
 {
+        u32 pll_sqsum;
         struct ath_softc *sc = container_of(work, struct ath_softc,
                                             hw_pll_work.work);
-        u32 pll_sqsum;
 
-        if (AR_SREV_9485(sc->sc_ah)) {
-                ath9k_ps_wakeup(sc);
-                pll_sqsum = ar9003_get_pll_sqsum_dvc(sc->sc_ah);
-                ath9k_ps_restore(sc);
-                ath_hw_pll_rx_hang_check(sc, pll_sqsum);
-                ieee80211_queue_delayed_work(sc->hw, &sc->hw_pll_work, HZ/5);
-        }
+        ath9k_ps_wakeup(sc);
+        pll_sqsum = ar9003_get_pll_sqsum_dvc(sc->sc_ah);
+        ath9k_ps_restore(sc);
+        if (ath_hw_pll_rx_hang_check(sc, pll_sqsum))
+                return;
+
+        ieee80211_queue_delayed_work(sc->hw, &sc->hw_pll_work,
+                                     msecs_to_jiffies(ATH_PLL_WORK_INTERVAL));
 }
 
 /*
@@ -293,7 +298,7 @@ void ath_paprd_calibrate(struct work_struct *work)
                 if (ar9003_paprd_create_curve(ah, caldata, chain)) {
                         ath_dbg(common, CALIBRATE,
                                 "PAPRD create curve failed on chain %d\n",
-                                                                   chain);
+                                chain);
                         break;
                 }
 
diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c
index 304769a3e179..b228aff481e1 100644
--- a/drivers/net/wireless/ath/ath9k/main.c
+++ b/drivers/net/wireless/ath/ath9k/main.c
@@ -158,6 +158,22 @@ static void ath_cancel_work(struct ath_softc *sc)
         cancel_work_sync(&sc->hw_reset_work);
 }
 
+static void ath_restart_work(struct ath_softc *sc)
+{
+        struct ath_common *common = ath9k_hw_common(sc->sc_ah);
+
+        ieee80211_queue_delayed_work(sc->hw, &sc->tx_complete_work, 0);
+
+        if (AR_SREV_9485(sc->sc_ah) || AR_SREV_9340(sc->sc_ah))
+                ieee80211_queue_delayed_work(sc->hw, &sc->hw_pll_work,
+                                     msecs_to_jiffies(ATH_PLL_WORK_INTERVAL));
+
+        ath_start_rx_poll(sc, 3);
+
+        if (!common->disable_ani)
+                ath_start_ani(common);
+}
+
 static bool ath_prepare_reset(struct ath_softc *sc, bool retry_tx, bool flush)
 {
         struct ath_hw *ah = sc->sc_ah;
@@ -209,11 +225,7 @@ static bool ath_complete_reset(struct ath_softc *sc, bool start)
                 if (sc->sc_flags & SC_OP_BEACONS)
                         ath_set_beacon(sc);
 
-                ieee80211_queue_delayed_work(sc->hw, &sc->tx_complete_work, 0);
-                ieee80211_queue_delayed_work(sc->hw, &sc->hw_pll_work, HZ/2);
-                ath_start_rx_poll(sc, 3);
-                if (!common->disable_ani)
-                        ath_start_ani(common);
+                ath_restart_work(sc);
         }
 
         if ((ah->caps.hw_caps & ATH9K_HW_CAP_ANT_DIV_COMB) && sc->ant_rx != 3) {