mac80211: enable power save only if DTIM period is available

Generally, the DTIM period is available after a beacon has
been received, and if no beacon has been received enabling
powersave is problematic anyway for synchronisation. Since
some drivers may require the DTIM period for powersave,
don't enable powersave until it becomes available in case
the scan/association managed to not receive a beacon.

Signed-off-by: Alexander Bondar <alexander.bondar@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index a8016c02a757b93f4cd0fc2aa0a854e81ba3b2cb..ef378b9a32ec4372b3eda99bb1b3526394e9bd85 100644 (file)
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -1390,6 +1390,9 @@ static bool ieee80211_powersave_allowed(struct ieee80211_sub_if_data *sdata)
                          IEEE80211_STA_CONNECTION_POLL))
                return false;
 
+       if (!sdata->vif.bss_conf.dtim_period)
+               return false;
+
        rcu_read_lock();
        sta = sta_info_get(sdata, mgd->bssid);
        if (sta)
@@ -3126,6 +3129,7 @@ ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata,
                }
 
                changed |= BSS_CHANGED_DTIM_PERIOD;
+               ieee80211_recalc_ps_vif(sdata);
        }
 
        if (elems.erp_info) {