From 7446da6910f1368273a55ca99acba18828306a6e Mon Sep 17 00:00:00 2001 From: Gabor Juhos Date: Sun, 21 Jun 2009 16:59:53 +0200 Subject: [PATCH 3/3] ath9k: serialize ath9k_ps_{wakeup,restore} calls These functions are changing the power mode of the chip, but this may have unpredictable effects, if another code are trying to set the power mode via 'ath9k_hw_setpower' in the same time from another context. Changes-licensed-under: ISC Signed-off-by: Gabor Juhos --- drivers/net/wireless/ath/ath9k/ath9k.h | 2 +- drivers/net/wireless/ath/ath9k/hw.c | 42 ++++++++++++++++++++++---------- 2 files changed, 30 insertions(+), 14 deletions(-) --- a/drivers/net/wireless/ath/ath9k/ath9k.h +++ b/drivers/net/wireless/ath/ath9k/ath9k.h @@ -561,7 +561,7 @@ struct ath_softc { u32 keymax; DECLARE_BITMAP(keymap, ATH_KEYMAX); u8 splitmic; - atomic_t ps_usecount; + unsigned long ps_usecount; enum ath9k_int imask; enum ath9k_ht_extprotspacing ht_extprotspacing; enum ath9k_ht_macmode tx_chan_width; --- a/drivers/net/wireless/ath/ath9k/hw.c +++ b/drivers/net/wireless/ath/ath9k/hw.c @@ -2787,23 +2787,39 @@ bool ath9k_hw_setpower(struct ath_hw *ah void ath9k_ps_wakeup(struct ath_softc *sc) { - if (atomic_inc_return(&sc->ps_usecount) == 1) - if (sc->sc_ah->power_mode != ATH9K_PM_AWAKE) { - sc->sc_ah->restore_mode = sc->sc_ah->power_mode; - ath9k_hw_setpower(sc->sc_ah, ATH9K_PM_AWAKE); - } + unsigned long flags; + + spin_lock_irqsave(&sc->sc_pm_lock, flags); + if (++sc->ps_usecount != 1) + goto unlock; + + if (sc->sc_ah->power_mode != ATH9K_PM_AWAKE) { + sc->sc_ah->restore_mode = sc->sc_ah->power_mode; + ath9k_hw_setpower_nolock(sc->sc_ah, ATH9K_PM_AWAKE); + } + + unlock: + spin_unlock_irqrestore(&sc->sc_pm_lock, flags); } void ath9k_ps_restore(struct ath_softc *sc) { - if (atomic_dec_and_test(&sc->ps_usecount)) - if ((sc->hw->conf.flags & IEEE80211_CONF_PS) && - !(sc->sc_flags & (SC_OP_WAIT_FOR_BEACON | - SC_OP_WAIT_FOR_CAB | - SC_OP_WAIT_FOR_PSPOLL_DATA | - SC_OP_WAIT_FOR_TX_ACK))) - ath9k_hw_setpower(sc->sc_ah, - sc->sc_ah->restore_mode); + unsigned long flags; + + spin_lock_irqsave(&sc->sc_pm_lock, flags); + if (--sc->ps_usecount != 0) + goto unlock; + + if ((sc->hw->conf.flags & IEEE80211_CONF_PS) && + !(sc->sc_flags & (SC_OP_WAIT_FOR_BEACON | + SC_OP_WAIT_FOR_CAB | + SC_OP_WAIT_FOR_PSPOLL_DATA | + SC_OP_WAIT_FOR_TX_ACK))) + ath9k_hw_setpower_nolock(sc->sc_ah, + sc->sc_ah->restore_mode); + + unlock: + spin_unlock_irqrestore(&sc->sc_pm_lock, flags); } /*