ath9k: merge reset related functions
authorFelix Fietkau <nbd@openwrt.org>
Fri, 2 Sep 2011 23:40:26 +0000 (01:40 +0200)
committerJohn W. Linville <linville@tuxdriver.com>
Wed, 14 Sep 2011 17:56:21 +0000 (13:56 -0400)
reduces unnecessary code duplication. Also takes the sc_pcu_lock within
ath_reset instead of callsites, which makes it possible to always cancel
all queued work items before the reset, possibly fixing a few race
conditions (work items vs reset) along with it.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
drivers/net/wireless/ath/ath9k/main.c

index 9a6db2964b186309d5fcada2086a67e9fdf64383..19c78be3dc414e74ab78bd605688998daad05fa9 100644 (file)
@@ -212,84 +212,58 @@ static int ath_update_survey_stats(struct ath_softc *sc)
        return ret;
 }
 
-/*
- * Set/change channels.  If the channel is really being changed, it's done
- * by reseting the chip.  To accomplish this we must first cleanup any pending
- * DMA, then restart stuff.
-*/
-static int ath_set_channel(struct ath_softc *sc, struct ieee80211_hw *hw,
-                   struct ath9k_channel *hchan)
+static void __ath_cancel_work(struct ath_softc *sc)
 {
-       struct ath_hw *ah = sc->sc_ah;
-       struct ath_common *common = ath9k_hw_common(ah);
-       struct ieee80211_conf *conf = &common->hw->conf;
-       bool fastcc = true, stopped;
-       struct ieee80211_channel *channel = hw->conf.channel;
-       struct ath9k_hw_cal_data *caldata = NULL;
-       int r;
-
-       if (sc->sc_flags & SC_OP_INVALID)
-               return -EIO;
-
-       sc->hw_busy_count = 0;
-
-       del_timer_sync(&common->ani.timer);
        cancel_work_sync(&sc->paprd_work);
        cancel_work_sync(&sc->hw_check_work);
-       cancel_work_sync(&sc->hw_reset_work);
        cancel_delayed_work_sync(&sc->tx_complete_work);
        cancel_delayed_work_sync(&sc->hw_pll_work);
+}
 
-       ath9k_ps_wakeup(sc);
+static void ath_cancel_work(struct ath_softc *sc)
+{
+       __ath_cancel_work(sc);
+       cancel_work_sync(&sc->hw_reset_work);
+}
 
-       spin_lock_bh(&sc->sc_pcu_lock);
+static bool ath_prepare_reset(struct ath_softc *sc, bool retry_tx, bool flush)
+{
+       struct ath_hw *ah = sc->sc_ah;
+       struct ath_common *common = ath9k_hw_common(ah);
+       bool ret;
 
-       /*
-        * This is only performed if the channel settings have
-        * actually changed.
-        *
-        * To switch channels clear any pending DMA operations;
-        * wait long enough for the RX fifo to drain, reset the
-        * hardware at the new frequency, and then re-enable
-        * the relevant bits of the h/w.
-        */
-       ath9k_hw_disable_interrupts(ah);
-       stopped = ath_drain_all_txq(sc, false);
+       ieee80211_stop_queues(sc->hw);
 
-       if (!ath_stoprecv(sc))
-               stopped = false;
+       sc->hw_busy_count = 0;
+       del_timer_sync(&common->ani.timer);
 
-       if (!ath9k_hw_check_alive(ah))
-               stopped = false;
+       ath9k_debug_samp_bb_mac(sc);
+       ath9k_hw_disable_interrupts(ah);
 
-       /* XXX: do not flush receive queue here. We don't want
-        * to flush data frames already in queue because of
-        * changing channel. */
+       ret = ath_drain_all_txq(sc, retry_tx);
 
-       if (!stopped || !(sc->sc_flags & SC_OP_OFFCHANNEL))
-               fastcc = false;
+       if (!ath_stoprecv(sc))
+               ret = false;
 
-       if (!(sc->sc_flags & SC_OP_OFFCHANNEL))
-               caldata = &sc->caldata;
+       if (!flush) {
+               if (ah->caps.hw_caps & ATH9K_HW_CAP_EDMA)
+                       ath_rx_tasklet(sc, 0, true);
+               ath_rx_tasklet(sc, 0, false);
+       } else {
+               ath_flushrecv(sc);
+       }
 
-       ath_dbg(common, ATH_DBG_CONFIG,
-               "(%u MHz) -> (%u MHz), conf_is_ht40: %d fastcc: %d\n",
-               sc->sc_ah->curchan->channel,
-               channel->center_freq, conf_is_ht40(conf),
-               fastcc);
+       return ret;
+}
 
-       r = ath9k_hw_reset(ah, hchan, caldata, fastcc);
-       if (r) {
-               ath_err(common,
-                       "Unable to reset channel (%u MHz), reset status %d\n",
-                       channel->center_freq, r);
-               goto ps_restore;
-       }
+static bool ath_complete_reset(struct ath_softc *sc, bool start)
+{
+       struct ath_hw *ah = sc->sc_ah;
+       struct ath_common *common = ath9k_hw_common(ah);
 
        if (ath_startrecv(sc) != 0) {
                ath_err(common, "Unable to restart recv logic\n");
-               r = -EIO;
-               goto ps_restore;
+               return false;
        }
 
        ath9k_cmn_update_txpow(ah, sc->curtxpow,
@@ -297,21 +271,93 @@ static int ath_set_channel(struct ath_softc *sc, struct ieee80211_hw *hw,
        ath9k_hw_set_interrupts(ah, ah->imask);
        ath9k_hw_enable_interrupts(ah);
 
-       if (!(sc->sc_flags & (SC_OP_OFFCHANNEL))) {
+       if (!(sc->sc_flags & (SC_OP_OFFCHANNEL)) && start) {
                if (sc->sc_flags & SC_OP_BEACONS)
                        ath_set_beacon(sc);
+
                ieee80211_queue_delayed_work(sc->hw, &sc->tx_complete_work, 0);
                ieee80211_queue_delayed_work(sc->hw, &sc->hw_pll_work, HZ/2);
                if (!common->disable_ani)
                        ath_start_ani(common);
        }
 
- ps_restore:
-       ieee80211_wake_queues(hw);
+       ieee80211_wake_queues(sc->hw);
+
+       return true;
+}
+
+static int ath_reset_internal(struct ath_softc *sc, struct ath9k_channel *hchan,
+                             bool retry_tx)
+{
+       struct ath_hw *ah = sc->sc_ah;
+       struct ath_common *common = ath9k_hw_common(ah);
+       struct ath9k_hw_cal_data *caldata = NULL;
+       bool fastcc = true;
+       bool flush = false;
+       int r;
+
+       __ath_cancel_work(sc);
+
+       spin_lock_bh(&sc->sc_pcu_lock);
 
+       if (!(sc->sc_flags & SC_OP_OFFCHANNEL)) {
+               fastcc = false;
+               caldata = &sc->caldata;
+       }
+
+       if (!hchan) {
+               fastcc = false;
+               flush = true;
+               hchan = ah->curchan;
+       }
+
+       if (fastcc && !ath9k_hw_check_alive(ah))
+               fastcc = false;
+
+       if (!ath_prepare_reset(sc, retry_tx, flush))
+               fastcc = false;
+
+       ath_dbg(common, ATH_DBG_CONFIG,
+               "Reset to %u MHz, HT40: %d fastcc: %d\n",
+               hchan->channel, !!(hchan->channelFlags & (CHANNEL_HT40MINUS |
+                                                         CHANNEL_HT40PLUS)),
+               fastcc);
+
+       r = ath9k_hw_reset(ah, hchan, caldata, fastcc);
+       if (r) {
+               ath_err(common,
+                       "Unable to reset channel, reset status %d\n", r);
+               goto out;
+       }
+
+       if (!ath_complete_reset(sc, true))
+               r = -EIO;
+
+out:
        spin_unlock_bh(&sc->sc_pcu_lock);
+       return r;
+}
+
+
+/*
+ * Set/change channels.  If the channel is really being changed, it's done
+ * by reseting the chip.  To accomplish this we must first cleanup any pending
+ * DMA, then restart stuff.
+*/
+static int ath_set_channel(struct ath_softc *sc, struct ieee80211_hw *hw,
+                   struct ath9k_channel *hchan)
+{
+       int r;
+
+       if (sc->sc_flags & SC_OP_INVALID)
+               return -EIO;
+
+       ath9k_ps_wakeup(sc);
+
+       r = ath_reset_internal(sc, hchan, false);
 
        ath9k_ps_restore(sc);
+
        return r;
 }
 
@@ -825,28 +871,13 @@ static void ath_radio_enable(struct ath_softc *sc, struct ieee80211_hw *hw)
                        channel->center_freq, r);
        }
 
-       ath9k_cmn_update_txpow(ah, sc->curtxpow,
-                              sc->config.txpowlimit, &sc->curtxpow);
-       if (ath_startrecv(sc) != 0) {
-               ath_err(common, "Unable to restart recv logic\n");
-               goto out;
-       }
-       if (sc->sc_flags & SC_OP_BEACONS)
-               ath_set_beacon(sc);     /* restart beacons */
-
-       /* Re-Enable  interrupts */
-       ath9k_hw_set_interrupts(ah, ah->imask);
-       ath9k_hw_enable_interrupts(ah);
+       ath_complete_reset(sc, true);
 
        /* Enable LED */
        ath9k_hw_cfg_output(ah, ah->led_pin,
                            AR_GPIO_OUTPUT_MUX_AS_OUTPUT);
        ath9k_hw_set_gpio(ah, ah->led_pin, 0);
 
-       ieee80211_wake_queues(hw);
-       ieee80211_queue_delayed_work(hw, &sc->hw_pll_work, HZ/2);
-
-out:
        spin_unlock_bh(&sc->sc_pcu_lock);
 
        ath9k_ps_restore(sc);
@@ -859,11 +890,10 @@ void ath_radio_disable(struct ath_softc *sc, struct ieee80211_hw *hw)
        int r;
 
        ath9k_ps_wakeup(sc);
-       cancel_delayed_work_sync(&sc->hw_pll_work);
 
-       spin_lock_bh(&sc->sc_pcu_lock);
+       ath_cancel_work(sc);
 
-       ieee80211_stop_queues(hw);
+       spin_lock_bh(&sc->sc_pcu_lock);
 
        /*
         * Keep the LED on when the radio is disabled
@@ -874,13 +904,7 @@ void ath_radio_disable(struct ath_softc *sc, struct ieee80211_hw *hw)
                ath9k_hw_cfg_gpio_input(ah, ah->led_pin);
        }
 
-       /* Disable interrupts */
-       ath9k_hw_disable_interrupts(ah);
-
-       ath_drain_all_txq(sc, false);   /* clear pending tx frames */
-
-       ath_stoprecv(sc);               /* turn off frame recv */
-       ath_flushrecv(sc);              /* flush recv queue */
+       ath_prepare_reset(sc, false, true);
 
        if (!ah->curchan)
                ah->curchan = ath9k_cmn_get_curchannel(hw, ah);
@@ -902,49 +926,11 @@ void ath_radio_disable(struct ath_softc *sc, struct ieee80211_hw *hw)
 
 static int ath_reset(struct ath_softc *sc, bool retry_tx)
 {
-       struct ath_hw *ah = sc->sc_ah;
-       struct ath_common *common = ath9k_hw_common(ah);
-       struct ieee80211_hw *hw = sc->hw;
        int r;
 
-       sc->hw_busy_count = 0;
-
-       ath9k_debug_samp_bb_mac(sc);
-       /* Stop ANI */
-
-       del_timer_sync(&common->ani.timer);
-
        ath9k_ps_wakeup(sc);
 
-       ieee80211_stop_queues(hw);
-
-       ath9k_hw_disable_interrupts(ah);
-       ath_drain_all_txq(sc, retry_tx);
-
-       ath_stoprecv(sc);
-       ath_flushrecv(sc);
-
-       r = ath9k_hw_reset(ah, sc->sc_ah->curchan, ah->caldata, false);
-       if (r)
-               ath_err(common,
-                       "Unable to reset hardware; reset status %d\n", r);
-
-       if (ath_startrecv(sc) != 0)
-               ath_err(common, "Unable to start recv logic\n");
-
-       /*
-        * We may be doing a reset in response to a request
-        * that changes the channel so update any state that
-        * might change as a result.
-        */
-       ath9k_cmn_update_txpow(ah, sc->curtxpow,
-                              sc->config.txpowlimit, &sc->curtxpow);
-
-       if ((sc->sc_flags & SC_OP_BEACONS) || !(sc->sc_flags & (SC_OP_OFFCHANNEL)))
-               ath_set_beacon(sc);     /* restart beacons */
-
-       ath9k_hw_set_interrupts(ah, ah->imask);
-       ath9k_hw_enable_interrupts(ah);
+       r = ath_reset_internal(sc, NULL, retry_tx);
 
        if (retry_tx) {
                int i;
@@ -957,12 +943,6 @@ static int ath_reset(struct ath_softc *sc, bool retry_tx)
                }
        }
 
-       ieee80211_wake_queues(hw);
-
-       /* Start ANI */
-       if (!common->disable_ani)
-               ath_start_ani(common);
-
        ath9k_ps_restore(sc);
 
        return r;
@@ -972,9 +952,7 @@ void ath_reset_work(struct work_struct *work)
 {
        struct ath_softc *sc = container_of(work, struct ath_softc, hw_reset_work);
 
-       spin_lock_bh(&sc->sc_pcu_lock);
        ath_reset(sc, true);
-       spin_unlock_bh(&sc->sc_pcu_lock);
 }
 
 void ath_hw_check(struct work_struct *work)
@@ -995,11 +973,8 @@ void ath_hw_check(struct work_struct *work)
        ath_dbg(common, ATH_DBG_RESET, "Possible baseband hang, "
                "busy=%d (try %d)\n", busy, sc->hw_busy_count + 1);
        if (busy >= 99) {
-               if (++sc->hw_busy_count >= 3) {
-                       spin_lock_bh(&sc->sc_pcu_lock);
-                       ath_reset(sc, true);
-                       spin_unlock_bh(&sc->sc_pcu_lock);
-               }
+               if (++sc->hw_busy_count >= 3)
+                       ieee80211_queue_work(sc->hw, &sc->hw_reset_work);
 
        } else if (busy >= 0)
                sc->hw_busy_count = 0;
@@ -1019,9 +994,7 @@ static void ath_hw_pll_rx_hang_check(struct ath_softc *sc, u32 pll_sqsum)
                        /* Rx is hung for more than 500ms. Reset it */
                        ath_dbg(common, ATH_DBG_RESET,
                                "Possible RX hang, resetting");
-                       spin_lock_bh(&sc->sc_pcu_lock);
-                       ath_reset(sc, true);
-                       spin_unlock_bh(&sc->sc_pcu_lock);
+                       ieee80211_queue_work(sc->hw, &sc->hw_reset_work);
                        count = 0;
                }
        } else
@@ -1092,28 +1065,6 @@ static int ath9k_start(struct ieee80211_hw *hw)
                goto mutex_unlock;
        }
 
-       /*
-        * This is needed only to setup initial state
-        * but it's best done after a reset.
-        */
-       ath9k_cmn_update_txpow(ah, sc->curtxpow,
-                       sc->config.txpowlimit, &sc->curtxpow);
-
-       /*
-        * Setup the hardware after reset:
-        * The receive engine is set going.
-        * Frame transmit is handled entirely
-        * in the frame output path; there's nothing to do
-        * here except setup the interrupt mask.
-        */
-       if (ath_startrecv(sc) != 0) {
-               ath_err(common, "Unable to start recv logic\n");
-               r = -EIO;
-               spin_unlock_bh(&sc->sc_pcu_lock);
-               goto mutex_unlock;
-       }
-       spin_unlock_bh(&sc->sc_pcu_lock);
-
        /* Setup our intr mask. */
        ah->imask = ATH9K_INT_TX | ATH9K_INT_RXEOL |
                    ATH9K_INT_RXORN | ATH9K_INT_FATAL |
@@ -1136,12 +1087,14 @@ static int ath9k_start(struct ieee80211_hw *hw)
 
        /* Disable BMISS interrupt when we're not associated */
        ah->imask &= ~(ATH9K_INT_SWBA | ATH9K_INT_BMISS);
-       ath9k_hw_set_interrupts(ah, ah->imask);
-       ath9k_hw_enable_interrupts(ah);
 
-       ieee80211_wake_queues(hw);
+       if (!ath_complete_reset(sc, false)) {
+               r = -EIO;
+               spin_unlock_bh(&sc->sc_pcu_lock);
+               goto mutex_unlock;
+       }
 
-       ieee80211_queue_delayed_work(sc->hw, &sc->tx_complete_work, 0);
+       spin_unlock_bh(&sc->sc_pcu_lock);
 
        if ((ah->btcoex_hw.scheme != ATH_BTCOEX_CFG_NONE) &&
            !ah->btcoex_hw.enabled) {
@@ -1234,11 +1187,7 @@ static void ath9k_stop(struct ieee80211_hw *hw)
 
        mutex_lock(&sc->mutex);
 
-       cancel_delayed_work_sync(&sc->tx_complete_work);
-       cancel_delayed_work_sync(&sc->hw_pll_work);
-       cancel_work_sync(&sc->paprd_work);
-       cancel_work_sync(&sc->hw_check_work);
-       cancel_work_sync(&sc->hw_reset_work);
+       ath_cancel_work(sc);
 
        if (sc->sc_flags & SC_OP_INVALID) {
                ath_dbg(common, ATH_DBG_ANY, "Device not present\n");
@@ -2349,9 +2298,11 @@ static void ath9k_flush(struct ieee80211_hw *hw, bool drop)
        ath9k_ps_wakeup(sc);
        spin_lock_bh(&sc->sc_pcu_lock);
        drain_txq = ath_drain_all_txq(sc, false);
+       spin_unlock_bh(&sc->sc_pcu_lock);
+
        if (!drain_txq)
                ath_reset(sc, false);
-       spin_unlock_bh(&sc->sc_pcu_lock);
+
        ath9k_ps_restore(sc);
        ieee80211_wake_queues(hw);