ath9k: Fix flushing in MCC mode

When we are attempting to switch to a new
channel context, the TX queues are flushed, but
the mac80211 queues are not stopped and traffic
can still come down to the driver.

This patch fixes it by stopping the queues
assigned to the current context/vif before
trying to flush.
Signed-off-by: Sujith Manoharan <c_manoha@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

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

@@ -1044,9 +1044,11 @@ static void ath_offchannel_channel_change(struct ath_softc *sc)
 void ath_chanctx_set_next(struct ath_softc *sc, bool force)
 {
 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
+	struct ath_chanctx *old_ctx;
 	struct timespec ts;
 	bool measure_time = false;
 	bool send_ps = false;
+	bool queues_stopped = false;
 
 	spin_lock_bh(&sc->chan_lock);
 	if (!sc->next_chan) {
@@ -1076,6 +1078,10 @@ void ath_chanctx_set_next(struct ath_softc *sc, bool force)
 			getrawmonotonic(&ts);
 			measure_time = true;
 		}
+
+		ath9k_chanctx_stop_queues(sc, sc->cur_chan);
+		queues_stopped = true;
+
 		__ath9k_flush(sc->hw, ~0, true);
 
 		if (ath_chanctx_send_ps_frame(sc, true))
@@ -1089,6 +1095,7 @@ void ath_chanctx_set_next(struct ath_softc *sc, bool force)
 			sc->cur_chan->tsf_val = ath9k_hw_gettsf64(sc->sc_ah);
 		}
 	}
+	old_ctx = sc->cur_chan;
 	sc->cur_chan = sc->next_chan;
 	sc->cur_chan->stopped = false;
 	sc->next_chan = NULL;
@@ -1111,7 +1118,16 @@ void ath_chanctx_set_next(struct ath_softc *sc, bool force)
 		if (measure_time)
 			sc->sched.channel_switch_time =
 				ath9k_hw_get_tsf_offset(&ts, NULL);
+		/*
+		 * A reset will ensure that all queues are woken up,
+		 * so there is no need to awaken them again.
+		 */
+		goto out;
 	}
+
+	if (queues_stopped)
+		ath9k_chanctx_wake_queues(sc, old_ctx);
+out:
 	if (send_ps)
 		ath_chanctx_send_ps_frame(sc, false);