2012-04-24 04:53:57

by Sujith Manoharan

[permalink] [raw]
Subject: [PATCH] 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 <[email protected]>
---
drivers/net/wireless/ath/ath9k/main.c | 43 ++++++++++++++++++++-------------
1 file changed, 26 insertions(+), 17 deletions(-)

diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c
index e4bc14b..dfa78e8 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)
--
1.7.10