mac80211: Extend the rate control API with an update callback

The AP can switch dynamically between 20/40 Mhz channel width,
in which case we switch the local operating channel, but the
rate control algorithm is not notified. This patch adds a new callback
to indicate such changes to the RC algorithm.

Currently, HT channel width change is notified, but this callback
can be used to indicate any new requirements that might come up later on.

Signed-off-by: Sujith <Sujith.Manoharan@atheros.com>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

net/mac80211/rate.h

@@ -62,6 +62,18 @@ static inline void rate_control_rate_init(struct sta_info *sta)
 	ref->ops->rate_init(ref->priv, sband, ista, priv_sta);
 }
 
+static inline void rate_control_rate_update(struct ieee80211_local *local,
+				    struct ieee80211_supported_band *sband,
+				    struct sta_info *sta, u32 changed)
+{
+	struct rate_control_ref *ref = local->rate_ctrl;
+	struct ieee80211_sta *ista = &sta->sta;
+	void *priv_sta = sta->rate_ctrl_priv;
+
+	if (ref->ops->rate_update)
+		ref->ops->rate_update(ref->priv, sband, ista,
+				      priv_sta, changed);
+}
 
 static inline void *rate_control_alloc_sta(struct rate_control_ref *ref,
 					   struct ieee80211_sta *sta,