mac80211: make listen_interval be limited by low level driver

This patch makes possible for a driver to specify maximal listen interval
The possibility for user to configure listen interval is not implemented
yet, currently the maximum provided by the driver or 1 is used.
Mac80211 uses config handler to set listen interval for to the driver.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Zhu Yi <yi.zhu@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

include/net/mac80211.h

@@ -432,6 +432,7 @@ enum ieee80211_conf_flags {
  * @radio_enabled: when zero, driver is required to switch off the radio.
  *	TODO make a flag
  * @beacon_int: beacon interval (TODO make interface config)
+ * @listen_interval: listen interval in units of beacon interval
  * @flags: configuration flags defined above
  * @power_level: requested transmit power (in dBm)
  * @max_antenna_gain: maximum antenna gain (in dBi)
@@ -446,6 +447,7 @@ struct ieee80211_conf {
 	int radio_enabled;
 
 	int beacon_int;
+	u16 listen_interval;
 	u32 flags;
 	int power_level;
 	int max_antenna_gain;
@@ -787,6 +789,9 @@ enum ieee80211_hw_flags {
  * @max_signal: Maximum value for signal (rssi) in RX information, used
  *     only when @IEEE80211_HW_SIGNAL_UNSPEC or @IEEE80211_HW_SIGNAL_DB
  *
+ * @max_listen_interval: max listen interval in units of beacon interval
+ *     that HW supports
+ *
  * @queues: number of available hardware transmit queues for
  *	data packets. WMM/QoS requires at least four, these
  *	queues need to have configurable access parameters.
@@ -814,7 +819,9 @@ struct ieee80211_hw {
 	unsigned int extra_tx_headroom;
 	int channel_change_time;
 	int vif_data_size;
-	u16 queues, ampdu_queues;
+	u16 queues;
+	u16 ampdu_queues;
+	u16 max_listen_interval;
 	s8 max_signal;
 };
 

net/mac80211/main.c

@@ -1689,6 +1689,11 @@ int ieee80211_register_hw(struct ieee80211_hw *hw)
 	if (local->hw.conf.beacon_int < 10)
 		local->hw.conf.beacon_int = 100;
 
+	if (local->hw.max_listen_interval == 0)
+		local->hw.max_listen_interval = 1;
+
+	local->hw.conf.listen_interval = local->hw.max_listen_interval;
+
 	local->wstats_flags |= local->hw.flags & (IEEE80211_HW_SIGNAL_UNSPEC |
 						  IEEE80211_HW_SIGNAL_DB |
 						  IEEE80211_HW_SIGNAL_DBM) ?

net/mac80211/mlme.c

@@ -774,15 +774,17 @@ static void ieee80211_send_assoc(struct net_device *dev,
 		mgmt->frame_control = IEEE80211_FC(IEEE80211_FTYPE_MGMT,
 						   IEEE80211_STYPE_REASSOC_REQ);
 		mgmt->u.reassoc_req.capab_info = cpu_to_le16(capab);
-		mgmt->u.reassoc_req.listen_interval = cpu_to_le16(1);
+		mgmt->u.reassoc_req.listen_interval =
+				cpu_to_le16(local->hw.conf.listen_interval);
 		memcpy(mgmt->u.reassoc_req.current_ap, ifsta->prev_bssid,
 		       ETH_ALEN);
 	} else {
 		skb_put(skb, 4);
 		mgmt->frame_control = IEEE80211_FC(IEEE80211_FTYPE_MGMT,
 						   IEEE80211_STYPE_ASSOC_REQ);
 		mgmt->u.assoc_req.capab_info = cpu_to_le16(capab);
-		mgmt->u.assoc_req.listen_interval = cpu_to_le16(1);
+		mgmt->u.reassoc_req.listen_interval =
+				cpu_to_le16(local->hw.conf.listen_interval);
 	}
 
 	/* SSID */