mac80211: Tear down aggregation sessions for suspend/resume

When the driver has been notified with a STA_REMOVE, it tears down
the internal ADDBA state. On resume, trying to initiate aggregation would
fail because mac80211 has not cleared the operational state for that <TID,STA>.
This can be fixed by tearing down the existing sessions on a suspend.

Also, the driver can initiate a new BA session when suspend is in progress.
This is fixed by marking the station as being in suspend state and
denying ADDBA requests for such STAs.

Signed-off-by: Sujith <Sujith.Manoharan@atheros.com>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/mac80211/pm.c b/net/mac80211/pm.c
index ef7be1c..1e6152a 100644
--- a/net/mac80211/pm.c
+++ b/net/mac80211/pm.c
@@ -21,6 +21,19 @@
 	list_for_each_entry(sdata, &local->interfaces, list)
 		ieee80211_disable_keys(sdata);
 
+	/* Tear down aggregation sessions */
+
+	rcu_read_lock();
+
+	if (hw->flags & IEEE80211_HW_AMPDU_AGGREGATION) {
+		list_for_each_entry_rcu(sta, &local->sta_list, list) {
+			set_sta_flags(sta, WLAN_STA_SUSPEND);
+			ieee80211_sta_tear_down_BA_sessions(sta);
+		}
+	}
+
+	rcu_read_unlock();
+
 	/* remove STAs */
 	if (local->ops->sta_notify) {
 		spin_lock_irqsave(&local->sta_lock, flags);
@@ -102,6 +115,18 @@
 		spin_unlock_irqrestore(&local->sta_lock, flags);
 	}
 
+	/* Clear Suspend state so that ADDBA requests can be processed */
+
+	rcu_read_lock();
+
+	if (hw->flags & IEEE80211_HW_AMPDU_AGGREGATION) {
+		list_for_each_entry_rcu(sta, &local->sta_list, list) {
+			clear_sta_flags(sta, WLAN_STA_SUSPEND);
+		}
+	}
+
+	rcu_read_unlock();
+
 	/* add back keys */
 	list_for_each_entry(sdata, &local->interfaces, list)
 		if (netif_running(sdata->dev))