From 167bf96dd87d2a8360cb9e9783006876dac4f579 Mon Sep 17 00:00:00 2001 From: Sujith Manoharan Date: Wed, 10 Sep 2014 19:16:00 +0530 Subject: [PATCH] ath9k: Fix beacon miss handling The NoA duration for a GO is half the beacon interval and a concurrent context like a STA can be active only for that duration, before switching back to the GO's operating channel. Currently, when multiple beacons are missed, the dwell time for the STA context is extended to improve the chances of receiving a beacon. But the NoA is not updated and this will cause problems since the GO is offline for a period that is longer than the advertised duration. Fix this by ensuring that the NoA is updated first before extending the time slot for the STA context. Also make sure that non-periodic NoA is used for a one-time, longer absence period. Signed-off-by: Sujith Manoharan Signed-off-by: John W. Linville --- drivers/net/wireless/ath/ath9k/ath9k.h | 1 + drivers/net/wireless/ath/ath9k/channel.c | 44 +++++++++++++++++------- 2 files changed, 33 insertions(+), 12 deletions(-) diff --git a/drivers/net/wireless/ath/ath9k/ath9k.h b/drivers/net/wireless/ath/ath9k/ath9k.h index 305db1a6889a..660c1515bb7d 100644 --- a/drivers/net/wireless/ath/ath9k/ath9k.h +++ b/drivers/net/wireless/ath/ath9k/ath9k.h @@ -380,6 +380,7 @@ struct ath_chanctx_sched { bool offchannel_pending; bool wait_switch; bool force_noa_update; + bool extend_absence; enum ath_chanctx_state state; u8 beacon_miss; diff --git a/drivers/net/wireless/ath/ath9k/channel.c b/drivers/net/wireless/ath/ath9k/channel.c index a42fd85def2a..a1b3282bd29e 100644 --- a/drivers/net/wireless/ath/ath9k/channel.c +++ b/drivers/net/wireless/ath/ath9k/channel.c @@ -371,13 +371,6 @@ void ath_chanctx_event(struct ath_softc *sc, struct ieee80211_vif *vif, sc->sched.switch_start_time = tsf_time; sc->cur_chan->last_beacon = sc->sched.next_tbtt; - /* If at least two consecutive beacons were missed on the STA - * chanctx, stay on the STA channel for one extra beacon period, - * to resync the timer properly. - */ - if (ctx->active && sc->sched.beacon_miss >= 2) - sc->sched.offchannel_duration = 3 * beacon_int / 2; - /* * If an offchannel switch is scheduled to happen after * a beacon transmission, update the NoA with one-shot @@ -405,6 +398,26 @@ void ath_chanctx_event(struct ath_softc *sc, struct ieee80211_vif *vif, break; } + + /* + * Clear the extend_absence flag if it had been + * set during the previous beacon transmission, + * since we need to revert to the normal NoA + * schedule. + */ + if (ctx->active && sc->sched.extend_absence) { + avp->noa_duration = 0; + sc->sched.extend_absence = false; + } + + /* If at least two consecutive beacons were missed on the STA + * chanctx, stay on the STA channel for one extra beacon period, + * to resync the timer properly. + */ + if (ctx->active && sc->sched.beacon_miss >= 2) { + avp->noa_duration = 0; + sc->sched.extend_absence = true; + } /* Prevent wrap-around issues */ if (avp->noa_duration && tsf_time - avp->noa_start > BIT(30)) avp->noa_duration = 0; @@ -418,11 +431,17 @@ void ath_chanctx_event(struct ath_softc *sc, struct ieee80211_vif *vif, (!avp->noa_duration || sc->sched.force_noa_update)) { avp->noa_index++; avp->noa_start = tsf_time; - avp->noa_duration = - TU_TO_USEC(cur_conf->beacon_interval) / 2 + - sc->sched.channel_switch_time; - if (test_bit(ATH_OP_SCANNING, &common->op_flags)) + if (sc->sched.extend_absence) + avp->noa_duration = (3 * beacon_int / 2) + + sc->sched.channel_switch_time; + else + avp->noa_duration = + TU_TO_USEC(cur_conf->beacon_interval) / 2 + + sc->sched.channel_switch_time; + + if (test_bit(ATH_OP_SCANNING, &common->op_flags) || + sc->sched.extend_absence) avp->periodic_noa = false; else avp->periodic_noa = true; @@ -520,7 +539,8 @@ void ath_chanctx_event(struct ath_softc *sc, struct ieee80211_vif *vif, sc->sched.wait_switch = false; tsf_time = TU_TO_USEC(cur_conf->beacon_interval) / 2; - if (sc->sched.beacon_miss >= 2) { + + if (sc->sched.extend_absence) { sc->sched.beacon_miss = 0; tsf_time *= 3; } -- 2.20.1