4 files changed, 84 insertions, 4 deletions

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index d6b0045788ce..0396cecd1d62 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -1069,6 +1069,13 @@ enum ieee80211_tkip_key_type {
  *      to decrypt group addressed frames, then IBSS RSN support is still
  *      possible but software crypto will be used. Advertise the wiphy flag
  *      only in that case.
+ *
+ * @IEEE80211_HW_AP_LINK_PS: When operating in AP mode the device
+ *      autonomously manages the PS status of connected stations. When
+ *      this flag is set mac80211 will not trigger PS mode for connected
+ *      stations based on the PM bit of incoming frames.
+ *      Use ieee80211_start_ps()/ieee8021_end_ps() to manually configure
+ *      the PS mode of connected stations.
  */
 enum ieee80211_hw_flags {
         IEEE80211_HW_HAS_RATE_CONTROL                   = 1<<0,
@@ -1093,6 +1100,7 @@ enum ieee80211_hw_flags {
         IEEE80211_HW_CONNECTION_MONITOR                 = 1<<19,
         IEEE80211_HW_SUPPORTS_CQM_RSSI                  = 1<<20,
         IEEE80211_HW_SUPPORTS_PER_STA_GTK               = 1<<21,
+        IEEE80211_HW_AP_LINK_PS                         = 1<<22,
 };
 
 /**
@@ -1701,7 +1709,9 @@ enum ieee80211_ampdu_mlme_action {
  *      station, AP, IBSS/WDS/mesh peer etc. This callback can sleep.
  *
  * @sta_notify: Notifies low level driver about power state transition of an
- *      associated station, AP,  IBSS/WDS/mesh peer etc. Must be atomic.
+ *      associated station, AP,  IBSS/WDS/mesh peer etc. For a VIF operating
+ *      in AP mode, this callback will not be called when the flag
+ *      %IEEE80211_HW_AP_LINK_PS is set. Must be atomic.
  *
  * @conf_tx: Configure TX queue parameters (EDCF (aifs, cw_min, cw_max),
  *      bursting) for a hardware TX queue.
@@ -2131,6 +2141,48 @@ static inline void ieee80211_rx_ni(struct ieee80211_hw *hw,
         local_bh_enable();
 }
 
+/**
+ * ieee80211_sta_ps_transition - PS transition for connected sta
+ *
+ * When operating in AP mode with the %IEEE80211_HW_AP_LINK_PS
+ * flag set, use this function to inform mac80211 about a connected station
+ * entering/leaving PS mode.
+ *
+ * This function may not be called in IRQ context or with softirqs enabled.
+ *
+ * Calls to this function for a single hardware must be synchronized against
+ * each other.
+ *
+ * The function returns -EINVAL when the requested PS mode is already set.
+ *
+ * @sta: currently connected sta
+ * @start: start or stop PS
+ */
+int ieee80211_sta_ps_transition(struct ieee80211_sta *sta, bool start);
+
+/**
+ * ieee80211_sta_ps_transition_ni - PS transition for connected sta
+ *                                  (in process context)
+ *
+ * Like ieee80211_sta_ps_transition() but can be called in process context
+ * (internally disables bottom halves). Concurrent call restriction still
+ * applies.
+ *
+ * @sta: currently connected sta
+ * @start: start or stop PS
+ */
+static inline int ieee80211_sta_ps_transition_ni(struct ieee80211_sta *sta,
+                                                  bool start)
+{
+        int ret;
+
+        local_bh_disable();
+        ret = ieee80211_sta_ps_transition(sta, start);
+        local_bh_enable();
+
+        return ret;
+}
+
 /*
  * The TX headroom reserved by mac80211 for its own tx_status functions.
  * This is enough for the radiotap header.
diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
index 7185c9316be2..d78d6fc333d2 100644
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -1105,7 +1105,8 @@ static void ap_sta_ps_start(struct sta_info *sta)
 
         atomic_inc(&sdata->bss->num_sta_ps);
         set_sta_flags(sta, WLAN_STA_PS_STA);
-        drv_sta_notify(local, sdata, STA_NOTIFY_SLEEP, &sta->sta);
+        if (!(local->hw.flags & IEEE80211_HW_AP_LINK_PS))
+                drv_sta_notify(local, sdata, STA_NOTIFY_SLEEP, &sta->sta);
 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
         printk(KERN_DEBUG "%s: STA %pM aid %d enters power save mode\n",
                sdata->name, sta->sta.addr, sta->sta.aid);
@@ -1134,6 +1135,27 @@ static void ap_sta_ps_end(struct sta_info *sta)
         ieee80211_sta_ps_deliver_wakeup(sta);
 }
 
+int ieee80211_sta_ps_transition(struct ieee80211_sta *sta, bool start)
+{
+        struct sta_info *sta_inf = container_of(sta, struct sta_info, sta);
+        bool in_ps;
+
+        WARN_ON(!(sta_inf->local->hw.flags & IEEE80211_HW_AP_LINK_PS));
+
+        /* Don't let the same PS state be set twice */
+        in_ps = test_sta_flags(sta_inf, WLAN_STA_PS_STA);
+        if ((start && in_ps) || (!start && !in_ps))
+                return -EINVAL;
+
+        if (start)
+                ap_sta_ps_start(sta_inf);
+        else
+                ap_sta_ps_end(sta_inf);
+
+        return 0;
+}
+EXPORT_SYMBOL(ieee80211_sta_ps_transition);
+
 static ieee80211_rx_result debug_noinline
 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
 {
@@ -1178,7 +1200,8 @@ ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
          * Change STA power saving mode only at the end of a frame
          * exchange sequence.
          */
-        if (!ieee80211_has_morefrags(hdr->frame_control) &&
+        if (!(sta->local->hw.flags & IEEE80211_HW_AP_LINK_PS) &&
+            !ieee80211_has_morefrags(hdr->frame_control) &&
             !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
             (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
              rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) {
diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c
index c426504ed1cf..5a11078827ab 100644
--- a/net/mac80211/sta_info.c
+++ b/net/mac80211/sta_info.c
@@ -899,7 +899,8 @@ void ieee80211_sta_ps_deliver_wakeup(struct sta_info *sta)
         struct ieee80211_local *local = sdata->local;
         int sent, buffered;
 
-        drv_sta_notify(local, sdata, STA_NOTIFY_AWAKE, &sta->sta);
+        if (!(local->hw.flags & IEEE80211_HW_AP_LINK_PS))
+                drv_sta_notify(local, sdata, STA_NOTIFY_AWAKE, &sta->sta);
 
         if (!skb_queue_empty(&sta->ps_tx_buf))
                 sta_info_clear_tim_bit(sta);
diff --git a/net/mac80211/status.c b/net/mac80211/status.c
index 38a797217a91..ffb0de9bc2fa 100644
--- a/net/mac80211/status.c
+++ b/net/mac80211/status.c
@@ -98,6 +98,10 @@ static void ieee80211_handle_filtered_frame(struct ieee80211_local *local,
          *  (b) always process RX events before TX status events if ordering
          *      can be unknown, for example with different interrupt status
          *      bits.
+         *  (c) if PS mode transitions are manual (i.e. the flag
+         *      %IEEE80211_HW_AP_LINK_PS is set), always process PS state
+         *      changes before calling TX status events if ordering can be
+         *      unknown.
          */
         if (test_sta_flags(sta, WLAN_STA_PS_STA) &&
             skb_queue_len(&sta->tx_filtered) < STA_MAX_TX_BUFFER) {