Commit 9d94674a authored by Luis R. Rodriguez's avatar Luis R. Rodriguez Committed by John W. Linville
Browse files

ath9k: simplify hw reset locking 

The new PCU lock is better placed so we can just contend
against that when trying to reset hardware.

This is part of a series of patches which fix stopping
TX DMA completley when requested on the driver.
For more details about this issue refer to this thread:

http://marc.info/?l=linux-wireless&m=128629803703756&w=2



Tested-by: default avatarBen Greear <greearb@candelatech.com>
Cc: Kyungwan Nam <kyungwan.nam@atheros.com>
Cc: stable@kernel.org
Signed-off-by: default avatarLuis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
parent 5d4c4282

drivers/net/wireless/ath/ath9k/ath9k.h

+0 −1
Original line number Diff line number Diff line
@@ -599,7 +599,6 @@ struct ath_softc { 
	struct ath_hw *sc_ah;

	void __iomem *mem;

	int irq;

	spinlock_t sc_resetlock;

	spinlock_t sc_serial_rw;

	spinlock_t sc_pm_lock;

	struct mutex mutex;

drivers/net/wireless/ath/ath9k/init.c

+0 −1
Original line number Diff line number Diff line
@@ -580,7 +580,6 @@ static int ath9k_init_softc(u16 devid, struct ath_softc *sc, u16 subsysid, 
	spin_lock_init(&common->cc_lock);



	spin_lock_init(&sc->wiphy_lock);

	spin_lock_init(&sc->sc_resetlock);

	spin_lock_init(&sc->sc_serial_rw);

	spin_lock_init(&sc->sc_pm_lock);

	mutex_init(&sc->mutex);

drivers/net/wireless/ath/ath9k/main.c

+6 −16
Original line number Diff line number Diff line
@@ -262,19 +262,15 @@ int ath_set_channel(struct ath_softc *sc, struct ieee80211_hw *hw, 
		  channel->center_freq, conf_is_ht40(conf),

		  fastcc);



	spin_lock_bh(&sc->sc_resetlock);



	r = ath9k_hw_reset(ah, hchan, caldata, fastcc);

	if (r) {

		ath_print(common, ATH_DBG_FATAL,

			  "Unable to reset channel (%u MHz), "

			  "reset status %d\n",

			  channel->center_freq, r);

		spin_unlock_bh(&sc->sc_resetlock);

		spin_unlock_bh(&sc->rx.pcu_lock);

		goto ps_restore;

	}

	spin_unlock_bh(&sc->sc_resetlock);



	if (ath_startrecv(sc) != 0) {

		ath_print(common, ATH_DBG_FATAL,
@@ -886,7 +882,6 @@ void ath_radio_enable(struct ath_softc *sc, struct ieee80211_hw *hw) 
		ah->curchan = ath_get_curchannel(sc, sc->hw);



	spin_lock_bh(&sc->rx.pcu_lock);

	spin_lock_bh(&sc->sc_resetlock);

	r = ath9k_hw_reset(ah, ah->curchan, ah->caldata, false);

	if (r) {

		ath_print(common, ATH_DBG_FATAL,
@@ -894,7 +889,6 @@ void ath_radio_enable(struct ath_softc *sc, struct ieee80211_hw *hw) 
			  "reset status %d\n",

			  channel->center_freq, r);

	}

	spin_unlock_bh(&sc->sc_resetlock);



	ath_update_txpow(sc);

	if (ath_startrecv(sc) != 0) {
@@ -951,7 +945,6 @@ void ath_radio_disable(struct ath_softc *sc, struct ieee80211_hw *hw) 
	if (!ah->curchan)

		ah->curchan = ath_get_curchannel(sc, hw);



	spin_lock_bh(&sc->sc_resetlock);

	r = ath9k_hw_reset(ah, ah->curchan, ah->caldata, false);

	if (r) {

		ath_print(ath9k_hw_common(sc->sc_ah), ATH_DBG_FATAL,
@@ -959,7 +952,6 @@ void ath_radio_disable(struct ath_softc *sc, struct ieee80211_hw *hw) 
			  "reset status %d\n",

			  channel->center_freq, r);

	}

	spin_unlock_bh(&sc->sc_resetlock);



	ath9k_hw_phy_disable(ah);
@@ -990,12 +982,10 @@ int ath_reset(struct ath_softc *sc, bool retry_tx) 
	ath_stoprecv(sc);

	ath_flushrecv(sc);



	spin_lock_bh(&sc->sc_resetlock);

	r = ath9k_hw_reset(ah, sc->sc_ah->curchan, ah->caldata, false);

	if (r)

		ath_print(common, ATH_DBG_FATAL,

			  "Unable to reset hardware; reset status %d\n", r);

	spin_unlock_bh(&sc->sc_resetlock);



	if (ath_startrecv(sc) != 0)

		ath_print(common, ATH_DBG_FATAL,
@@ -1166,18 +1156,15 @@ static int ath9k_start(struct ieee80211_hw *hw) 
	 * and then setup of the interrupt mask.

	 */

	spin_lock_bh(&sc->rx.pcu_lock);

	spin_lock_bh(&sc->sc_resetlock);

	r = ath9k_hw_reset(ah, init_channel, ah->caldata, false);

	if (r) {

		ath_print(common, ATH_DBG_FATAL,

			  "Unable to reset hardware; reset status %d "

			  "(freq %u MHz)\n", r,

			  curchan->center_freq);

		spin_unlock_bh(&sc->sc_resetlock);

		spin_unlock_bh(&sc->rx.pcu_lock);

		goto mutex_unlock;

	}

	spin_unlock_bh(&sc->sc_resetlock);



	/*

	 * This is needed only to setup initial state
@@ -1398,14 +1385,17 @@ static void ath9k_stop(struct ieee80211_hw *hw) 
	 * before setting the invalid flag. */

	ath9k_hw_disable_interrupts(ah);



	spin_lock_bh(&sc->rx.pcu_lock);

	if (!(sc->sc_flags & SC_OP_INVALID)) {

		ath_drain_all_txq(sc, false);

		spin_lock_bh(&sc->rx.pcu_lock);

		ath_stoprecv(sc);

		ath9k_hw_phy_disable(ah);

	} else

		spin_unlock_bh(&sc->rx.pcu_lock);

	} else {

		spin_lock_bh(&sc->rx.pcu_lock);

		sc->rx.rxlink = NULL;

		spin_unlock_bh(&sc->rx.pcu_lock);

	}



	/* disable HAL and put h/w to sleep */

	ath9k_hw_disable(ah);

drivers/net/wireless/ath/ath9k/xmit.c

+2 −2
Original line number Diff line number Diff line
@@ -1148,13 +1148,13 @@ void ath_drain_all_txq(struct ath_softc *sc, bool retry_tx) 
		ath_print(common, ATH_DBG_FATAL,

			  "Failed to stop TX DMA. Resetting hardware!\n");



		spin_lock_bh(&sc->sc_resetlock);

		spin_lock_bh(&sc->rx.pcu_lock);

		r = ath9k_hw_reset(ah, sc->sc_ah->curchan, ah->caldata, false);

		if (r)

			ath_print(common, ATH_DBG_FATAL,

				  "Unable to reset hardware; reset status %d\n",

				  r);

		spin_unlock_bh(&sc->sc_resetlock);

		spin_unlock_bh(&sc->rx.pcu_lock);

	}



	for (i = 0; i < ATH9K_NUM_TX_QUEUES; i++) {