mac80211: cancel/restart all timers across suspend/resume

We forgot to cancel all timers in mac80211 when suspending.
In particular we forgot to deal with some things that can
cause hardware reconfiguration -- while it is down.

While at it we go ahead and add a warning in ieee80211_sta_work()
if its run while the suspend->resume cycle is in effect. This
should not happen and if it does it would indicate there is
a bug lurking in either mac80211 or mac80211 drivers.

With this now wpa_supplicant doesn't blink when I go to suspend
and resume where as before there where issues with some timers
running during the suspend->resume cycle. This caused a lot of
incorrect assumptions and would at times bring back the device
in an incoherent, but mostly recoverable, state.

Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 29 insertions, 0 deletions

diff --git a/net/mac80211/ibss.c b/net/mac80211/ibss.c
index c236079ed38a..ebf7318b610f 100644
--- a/net/mac80211/ibss.c
+++ b/net/mac80211/ibss.c
@@ -737,6 +737,9 @@ static void ieee80211_ibss_work(struct work_struct *work)
         struct ieee80211_if_ibss *ifibss;
         struct sk_buff *skb;
 
+        if (WARN_ON(local->suspended))
+                return;
+
         if (!netif_running(sdata->dev))
                 return;
 
@@ -773,10 +776,36 @@ static void ieee80211_ibss_timer(unsigned long data)
         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
         struct ieee80211_local *local = sdata->local;
 
+        if (local->quiescing) {
+                ifibss->timer_running = true;
+                return;
+        }
+
         set_bit(IEEE80211_IBSS_REQ_RUN, &ifibss->request);
         queue_work(local->hw.workqueue, &ifibss->work);
 }
 
+#ifdef CONFIG_PM
+void ieee80211_ibss_quiesce(struct ieee80211_sub_if_data *sdata)
+{
+        struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
+
+        cancel_work_sync(&ifibss->work);
+        if (del_timer_sync(&ifibss->timer))
+                ifibss->timer_running = true;
+}
+
+void ieee80211_ibss_restart(struct ieee80211_sub_if_data *sdata)
+{
+        struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
+
+        if (ifibss->timer_running) {
+                add_timer(&ifibss->timer);
+                ifibss->timer_running = false;
+        }
+}
+#endif
+
 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
 {
         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;