From: Sujith Manoharan Date: Fri, 17 Oct 2014 07:40:16 +0530 Subject: [PATCH] ath9k: Fix MCC flush timeout In MCC mode, the duration for a channel context is half the beacon interval and having a large flush timeout will adversely affect GO operation, since the default value of 200ms will overshoot the advertised NoA absence duration. The scheduler initiates a channel context switch only when the slot duration for the current context expires, so there is no possibility of having a fixed timeout for flush. Since the channel_switch_time is added to the absence duration when the GO sets up the NoA attribute, this is the maximum time that we have to flush the TX queues. The duration is very small, but we don't have a choice in MCC mode. Signed-off-by: Sujith Manoharan --- --- a/drivers/net/wireless/ath/ath9k/channel.c +++ b/drivers/net/wireless/ath/ath9k/channel.c @@ -199,6 +199,7 @@ static const char *chanctx_state_string( void ath_chanctx_check_active(struct ath_softc *sc, struct ath_chanctx *ctx) { struct ath_common *common = ath9k_hw_common(sc->sc_ah); + struct ath_chanctx *ictx; struct ath_vif *avp; bool active = false; u8 n_active = 0; @@ -206,6 +207,8 @@ void ath_chanctx_check_active(struct ath if (!ctx) return; + ictx = ctx; + list_for_each_entry(avp, &ctx->vifs, list) { struct ieee80211_vif *vif = avp->vif; @@ -228,12 +231,23 @@ void ath_chanctx_check_active(struct ath n_active++; } + spin_lock_bh(&sc->chan_lock); + if (n_active <= 1) { + ictx->flush_timeout = HZ / 5; clear_bit(ATH_OP_MULTI_CHANNEL, &common->op_flags); + spin_unlock_bh(&sc->chan_lock); return; } - if (test_and_set_bit(ATH_OP_MULTI_CHANNEL, &common->op_flags)) + + ictx->flush_timeout = usecs_to_jiffies(sc->sched.channel_switch_time); + + if (test_and_set_bit(ATH_OP_MULTI_CHANNEL, &common->op_flags)) { + spin_unlock_bh(&sc->chan_lock); return; + } + + spin_unlock_bh(&sc->chan_lock); if (ath9k_is_chanctx_enabled()) { ath_chanctx_event(sc, NULL,