ath9k: check old power mode before clearing cycle counters

ath9k_ps_wakeup() clears the cycle counters after waking up the
hardware using ath9k_hw_setpower, however if power save is disabled,
then the counters will contain useful data, which then gets discarded.
Fix this by checking the old power mode before discarding any data.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c
index 09dcdd7882e6830ff8723832341e2755ecd7f08f..25d3ef4c338e1eb45800b45fec112fc064c095af 100644 (file)
--- a/drivers/net/wireless/ath/ath9k/main.c
+++ b/drivers/net/wireless/ath/ath9k/main.c
@@ -94,11 +94,13 @@ void ath9k_ps_wakeup(struct ath_softc *sc)
 {
        struct ath_common *common = ath9k_hw_common(sc->sc_ah);
        unsigned long flags;
+       enum ath9k_power_mode power_mode;
 
        spin_lock_irqsave(&sc->sc_pm_lock, flags);
        if (++sc->ps_usecount != 1)
                goto unlock;
 
+       power_mode = sc->sc_ah->power_mode;
        ath9k_hw_setpower(sc->sc_ah, ATH9K_PM_AWAKE);
 
        /*
@@ -106,10 +108,12 @@ void ath9k_ps_wakeup(struct ath_softc *sc)
         * useful data. Better clear them now so that they don't mess up
         * survey data results.
         */
-       spin_lock(&common->cc_lock);
-       ath_hw_cycle_counters_update(common);
-       memset(&common->cc_survey, 0, sizeof(common->cc_survey));
-       spin_unlock(&common->cc_lock);
+       if (power_mode != ATH9K_PM_AWAKE) {
+               spin_lock(&common->cc_lock);
+               ath_hw_cycle_counters_update(common);
+               memset(&common->cc_survey, 0, sizeof(common->cc_survey));
+               spin_unlock(&common->cc_lock);
+       }
 
  unlock:
        spin_unlock_irqrestore(&sc->sc_pm_lock, flags);