2 files changed, 32 insertions, 7 deletions

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 183956e4930a..446dbf75a1c5 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -517,7 +517,7 @@ struct ieee80211_rx_status {
  * Flags to define PHY configuration options
  *
  * @IEEE80211_CONF_RADIOTAP: add radiotap header at receive time (if supported)
- * @IEEE80211_CONF_PS: Enable 802.11 power save mode
+ * @IEEE80211_CONF_PS: Enable 802.11 power save mode (managed mode only)
  */
 enum ieee80211_conf_flags {
         IEEE80211_CONF_RADIOTAP         = (1<<0),
@@ -553,14 +553,26 @@ enum ieee80211_conf_changed {
  *
  * This struct indicates how the driver shall configure the hardware.
  *
+ * @flags: configuration flags defined above
+ *
  * @radio_enabled: when zero, driver is required to switch off the radio.
  * @beacon_int: beacon interval (TODO make interface config)
+ *
  * @listen_interval: listen interval in units of beacon interval
- * @flags: configuration flags defined above
+ * @max_sleep_interval: the maximum number of beacon intervals to sleep for
+ *      before checking the beacon for a TIM bit (managed mode only); this
+ *      value will be only achievable between DTIM frames, the hardware
+ *      needs to check for the multicast traffic bit in DTIM beacons.
+ *      This variable is valid only when the CONF_PS flag is set.
+ * @dynamic_ps_timeout: The dynamic powersave timeout (in ms), see the
+ *      powersave documentation below. This variable is valid only when
+ *      the CONF_PS flag is set.
+ *
  * @power_level: requested transmit power (in dBm)
- * @dynamic_ps_timeout: dynamic powersave timeout (in ms)
+ *
  * @channel: the channel to tune to
  * @channel_type: the channel (HT) type
+ *
  * @long_frame_max_tx_count: Maximum number of transmissions for a "long" frame
  *    (a frame not RTS protected), called "dot11LongRetryLimit" in 802.11,
  *    but actually means the number of transmissions not the number of retries
@@ -572,6 +584,7 @@ struct ieee80211_conf {
         int beacon_int;
         u32 flags;
         int power_level, dynamic_ps_timeout;
+        int max_sleep_interval;
 
         u16 listen_interval;
         bool radio_enabled;
diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index e819c02d13f0..df27c68620c9 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -545,10 +545,19 @@ void ieee80211_recalc_ps(struct ieee80211_local *local, s32 latency)
                 beaconint_us = ieee80211_tu_to_usec(
                                         found->vif.bss_conf.beacon_int);
 
-                if (beaconint_us > latency)
+                if (beaconint_us > latency) {
                         local->ps_sdata = NULL;
-                else
+                } else {
+                        u8 dtimper = found->vif.bss_conf.dtim_period;
+                        int maxslp = 1;
+
+                        if (dtimper > 1)
+                                maxslp = min_t(int, dtimper,
+                                                    latency / beaconint_us);
+
+                        local->hw.conf.max_sleep_interval = maxslp;
                         local->ps_sdata = found;
+                }
         } else {
                 local->ps_sdata = NULL;
         }
@@ -851,8 +860,11 @@ static void ieee80211_set_associated(struct ieee80211_sub_if_data *sdata,
         ieee80211_bss_info_change_notify(sdata, bss_info_changed);
 
         /* will be same as sdata */
-        if (local->ps_sdata)
-                ieee80211_enable_ps(local, sdata);
+        if (local->ps_sdata) {
+                mutex_lock(&local->iflist_mtx);
+                ieee80211_recalc_ps(local, -1);
+                mutex_unlock(&local->iflist_mtx);
+        }
 
         netif_tx_start_all_queues(sdata->dev);
         netif_carrier_on(sdata->dev);