From 7c3f4bbedc241ddcd3abe1f419c356e625231da1 Mon Sep 17 00:00:00 2001 From: Vivek Natarajan Date: Mon, 30 Nov 2009 16:50:53 +0530 Subject: [PATCH] mac80211: Fix dynamic power save for scanning. Not only ps_sdata but also IEEE80211_CONF_PS is to be considered before restoring PS in scan_ps_disable(). For instance, when ps_sdata is set but CONF_PS is not set just because the dynamic timer is still running, a sw scan leads to setting of CONF_PS in scan_ps_disable instead of restarting the dynamic PS timer. Also for the above case, a null data frame is to be sent after returning to operating channel which was not happening with the current implementation. This patch fixes this too. Signed-off-by: Vivek Natarajan Reviewed-by: Kalle Valo Signed-off-by: John W. Linville --- net/mac80211/ieee80211_i.h | 1 + net/mac80211/scan.c | 20 ++++++++++++++++---- 2 files changed, 17 insertions(+), 4 deletions(-) diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h index 419f186cfcf0..91dc8636d644 100644 --- a/net/mac80211/ieee80211_i.h +++ b/net/mac80211/ieee80211_i.h @@ -746,6 +746,7 @@ struct ieee80211_local { unsigned int wmm_acm; /* bit field of ACM bits (BIT(802.1D tag)) */ bool pspolling; + bool scan_ps_enabled; /* * PS can only be enabled when we have exactly one managed * interface (and monitors) in PS, this then points there. diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c index 4cf387c944bf..f1a4c7160300 100644 --- a/net/mac80211/scan.c +++ b/net/mac80211/scan.c @@ -227,7 +227,8 @@ static bool ieee80211_prep_hw_scan(struct ieee80211_local *local) static void ieee80211_scan_ps_enable(struct ieee80211_sub_if_data *sdata) { struct ieee80211_local *local = sdata->local; - bool ps = false; + + local->scan_ps_enabled = false; /* FIXME: what to do when local->pspolling is true? */ @@ -235,12 +236,13 @@ static void ieee80211_scan_ps_enable(struct ieee80211_sub_if_data *sdata) cancel_work_sync(&local->dynamic_ps_enable_work); if (local->hw.conf.flags & IEEE80211_CONF_PS) { - ps = true; + local->scan_ps_enabled = true; local->hw.conf.flags &= ~IEEE80211_CONF_PS; ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS); } - if (!ps || !(local->hw.flags & IEEE80211_HW_PS_NULLFUNC_STACK)) + if (!(local->scan_ps_enabled) || + !(local->hw.flags & IEEE80211_HW_PS_NULLFUNC_STACK)) /* * If power save was enabled, no need to send a nullfunc * frame because AP knows that we are sleeping. But if the @@ -261,7 +263,7 @@ static void ieee80211_scan_ps_disable(struct ieee80211_sub_if_data *sdata) if (!local->ps_sdata) ieee80211_send_nullfunc(local, sdata, 0); - else { + else if (local->scan_ps_enabled) { /* * In !IEEE80211_HW_PS_NULLFUNC_STACK case the hardware * will send a nullfunc frame with the powersave bit set @@ -277,6 +279,16 @@ static void ieee80211_scan_ps_disable(struct ieee80211_sub_if_data *sdata) */ local->hw.conf.flags |= IEEE80211_CONF_PS; ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS); + } else if (local->hw.conf.dynamic_ps_timeout > 0) { + /* + * If IEEE80211_CONF_PS was not set and the dynamic_ps_timer + * had been running before leaving the operating channel, + * restart the timer now and send a nullfunc frame to inform + * the AP that we are awake. + */ + ieee80211_send_nullfunc(local, sdata, 0); + mod_timer(&local->dynamic_ps_timer, jiffies + + msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout)); } } -- 2.34.1