commit c2731b814e2aaaa40072ee761b7373c052d86e37 upstream

Upon a failure we never call ath9k_ps_restore() on ath_radio_enable(),
this will throw off the sc->ps_usecount. When the sc->ps_usecount
is > 0 we never put the chip to full sleep. This drains battery,
and will also make the chip fail upon resume with:

ath: Starting driver with initial channel: 5745 MHz
ath: timeout (100000 us) on reg 0x7000: 0xdeadbeef & 0x00000003 != 0x00000000

This would make the chip useless upon resume.

I cannot prove this can happen but in theory it is so best to
avoid this race completely and not have users complain about
a broken device after resume.

Cc: sta...@kernel.org
Cc: Paul Stewart <ps...@google.com>
Cc: Amod Bodas <amod.bo...@atheros.com>
Signed-off-by: Luis R. Rodriguez <lrodrig...@atheros.com>
Signed-off-by: John W. Linville <linvi...@tuxdriver.com>
---
 drivers/net/wireless/ath/ath9k/main.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/wireless/ath/ath9k/main.c 
b/drivers/net/wireless/ath/ath9k/main.c
index 5a5f59f..20cdf3d 100644
--- a/drivers/net/wireless/ath/ath9k/main.c
+++ b/drivers/net/wireless/ath/ath9k/main.c
@@ -898,8 +898,7 @@ void ath_radio_enable(struct ath_softc *sc, struct 
ieee80211_hw *hw)
        if (ath_startrecv(sc) != 0) {
                ath_print(common, ATH_DBG_FATAL,
                          "Unable to restart recv logic\n");
-               spin_unlock_bh(&sc->sc_pcu_lock);
-               return;
+               goto out;
        }
        if (sc->sc_flags & SC_OP_BEACONS)
                ath_beacon_config(sc, NULL);    /* restart beacons */
@@ -913,6 +912,7 @@ void ath_radio_enable(struct ath_softc *sc, struct 
ieee80211_hw *hw)
        ath9k_hw_set_gpio(ah, ah->led_pin, 0);
 
        ieee80211_wake_queues(hw);
+out:
        spin_unlock_bh(&sc->sc_pcu_lock);
 
        ath9k_ps_restore(sc);
-- 
1.7.4.15.g7811d

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