ath9k: Fix IDLE Powersave

* PS_WAIT_FOR_TX_ACK is used in network-sleep mode and checking
  it for handling IDLE transitions is incorrect. Fix this.

* RX PCU/DMA engines have to be stopped before setting the chip into
  full-sleep mode - otherwise the chip becomes mute.

* Make things a bit clear by checking explicitly for network-sleep
  mode in the tx() routine and add a couple of debug statements
  to aid PS debugging.

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

1 files changed, 26 insertions, 17 deletions

diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c
index 1fc6e331589a..f4b7334cd27c 100644
--- a/drivers/net/wireless/ath/ath9k/main.c
+++ b/drivers/net/wireless/ath/ath9k/main.c
@@ -113,21 +113,25 @@ void ath9k_ps_restore(struct ath_softc *sc)
         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
         enum ath9k_power_mode mode;
         unsigned long flags;
+        bool reset;
 
         spin_lock_irqsave(&sc->sc_pm_lock, flags);
         if (--sc->ps_usecount != 0)
                 goto unlock;
 
-        if (sc->ps_idle && (sc->ps_flags & PS_WAIT_FOR_TX_ACK))
+        if (sc->ps_idle) {
+                ath9k_hw_setrxabort(sc->sc_ah, 1);
+                ath9k_hw_stopdmarecv(sc->sc_ah, &reset);
                 mode = ATH9K_PM_FULL_SLEEP;
-        else if (sc->ps_enabled &&
-                 !(sc->ps_flags & (PS_WAIT_FOR_BEACON |
-                              PS_WAIT_FOR_CAB |
-                              PS_WAIT_FOR_PSPOLL_DATA |
-                              PS_WAIT_FOR_TX_ACK)))
+        } else if (sc->ps_enabled &&
+                   !(sc->ps_flags & (PS_WAIT_FOR_BEACON |
+                                     PS_WAIT_FOR_CAB |
+                                     PS_WAIT_FOR_PSPOLL_DATA |
+                                     PS_WAIT_FOR_TX_ACK))) {
                 mode = ATH9K_PM_NETWORK_SLEEP;
-        else
+        } else {
                 goto unlock;
+        }
 
         spin_lock(&common->cc_lock);
         ath_hw_cycle_counters_update(common);
@@ -1100,14 +1104,7 @@ static void ath9k_tx(struct ieee80211_hw *hw, struct sk_buff *skb)
                 }
         }
 
-        /*
-         * Cannot tx while the hardware is in full sleep, it first needs a full
-         * chip reset to recover from that
-         */
-        if (unlikely(sc->sc_ah->power_mode == ATH9K_PM_FULL_SLEEP))
-                goto exit;
-
-        if (unlikely(sc->sc_ah->power_mode != ATH9K_PM_AWAKE)) {
+        if (unlikely(sc->sc_ah->power_mode == ATH9K_PM_NETWORK_SLEEP)) {
                 /*
                  * We are using PS-Poll and mac80211 can request TX while in
                  * power save mode. Need to wake up hardware for the TX to be
@@ -1126,12 +1123,21 @@ static void ath9k_tx(struct ieee80211_hw *hw, struct sk_buff *skb)
                 }
                 /*
                  * The actual restore operation will happen only after
-                 * the sc_flags bit is cleared. We are just dropping
+                 * the ps_flags bit is cleared. We are just dropping
                  * the ps_usecount here.
                  */
                 ath9k_ps_restore(sc);
         }
 
+        /*
+         * Cannot tx while the hardware is in full sleep, it first needs a full
+         * chip reset to recover from that
+         */
+        if (unlikely(sc->sc_ah->power_mode == ATH9K_PM_FULL_SLEEP)) {
+                ath_err(common, "TX while HW is in FULL_SLEEP mode\n");
+                goto exit;
+        }
+
         memset(&txctl, 0, sizeof(struct ath_tx_control));
         txctl.txq = sc->tx.txq_map[skb_get_queue_mapping(skb)];
 
@@ -1528,6 +1534,7 @@ static void ath9k_remove_interface(struct ieee80211_hw *hw,
 static void ath9k_enable_ps(struct ath_softc *sc)
 {
         struct ath_hw *ah = sc->sc_ah;
+        struct ath_common *common = ath9k_hw_common(ah);
 
         sc->ps_enabled = true;
         if (!(ah->caps.hw_caps & ATH9K_HW_CAP_AUTOSLEEP)) {
@@ -1537,11 +1544,13 @@ static void ath9k_enable_ps(struct ath_softc *sc)
                 }
                 ath9k_hw_setrxabort(ah, 1);
         }
+        ath_dbg(common, PS, "PowerSave enabled\n");
 }
 
 static void ath9k_disable_ps(struct ath_softc *sc)
 {
         struct ath_hw *ah = sc->sc_ah;
+        struct ath_common *common = ath9k_hw_common(ah);
 
         sc->ps_enabled = false;
         ath9k_hw_setpower(ah, ATH9K_PM_AWAKE);
@@ -1556,7 +1565,7 @@ static void ath9k_disable_ps(struct ath_softc *sc)
                         ath9k_hw_set_interrupts(ah);
                 }
         }
-
+        ath_dbg(common, PS, "PowerSave disabled\n");
 }
 
 static int ath9k_config(struct ieee80211_hw *hw, u32 changed)