mac80211: add HW flag for disabling auto link-PS in AP mode

When operating in AP mode the wl1271 hardware filters out null-data
packets as well as management packets. This makes it impossible for
mac80211 to monitor the PS mode by using the PM bit of incoming frames.

Implement a HW flag to indicate that mac80211 should ignore the PM bit.
In addition, expose ieee80211_sta_ps_transition() to make low-level
drivers capable of controlling PS-mode.

Signed-off-by: Arik Nemtsov <arik@wizery.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

3 files changed, 31 insertions, 3 deletions

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) {