cfg80211: add nl80211 beacon-only statistics

Add these two values:
 * BEACON_RX: number of beacons received from this peer
 * BEACON_SIGNAL_AVG: signal strength average for beacons only

These can then be used for Android Lollipop's statistics request.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

include/net/cfg80211.h

@@ -987,6 +987,9 @@ struct sta_bss_parameters {
  * @nonpeer_pm: non-peer mesh STA power save mode
  * @expected_throughput: expected throughput in kbps (including 802.11 headers)
  *	towards this station.
+ * @rx_beacon: number of beacons received from this peer
+ * @rx_beacon_signal_avg: signal strength average (in dBm) for beacons received
+ *	from this peer
  */
 struct station_info {
 	u32 filled;
@@ -1026,6 +1029,9 @@ struct station_info {
 	enum nl80211_mesh_power_mode nonpeer_pm;
 
 	u32 expected_throughput;
+
+	u64 rx_beacon;
+	u8 rx_beacon_signal_avg;
 };
 
 /**

include/uapi/linux/nl80211.h

@@ -2375,6 +2375,9 @@ enum nl80211_sta_bss_param {
  *	802.11 header (u32, kbps)
  * @NL80211_STA_INFO_RX_DROP_MISC: RX packets dropped for unspecified reasons
  *	(u64)
+ * @NL80211_STA_INFO_BEACON_RX: number of beacons received from this peer (u64)
+ * @NL80211_STA_INFO_BEACON_SIGNAL_AVG: signal strength average
+ *	for beacons only (u8, dBm)
  * @__NL80211_STA_INFO_AFTER_LAST: internal
  * @NL80211_STA_INFO_MAX: highest possible station info attribute
  */
@@ -2408,6 +2411,8 @@ enum nl80211_sta_info {
 	NL80211_STA_INFO_CHAIN_SIGNAL_AVG,
 	NL80211_STA_INFO_EXPECTED_THROUGHPUT,
 	NL80211_STA_INFO_RX_DROP_MISC,
+	NL80211_STA_INFO_BEACON_RX,
+	NL80211_STA_INFO_BEACON_SIGNAL_AVG,
 
 	/* keep last */
 	__NL80211_STA_INFO_AFTER_LAST,

net/wireless/nl80211.c

@@ -3768,6 +3768,8 @@ static int nl80211_send_station(struct sk_buff *msg, u32 cmd, u32 portid,
 
 	PUT_SINFO(T_OFFSET, t_offset, u64);
 	PUT_SINFO(RX_DROP_MISC, rx_dropped_misc, u64);
+	PUT_SINFO(BEACON_RX, rx_beacon, u64);
+	PUT_SINFO(BEACON_SIGNAL_AVG, rx_beacon_signal_avg, u8);
 
 #undef PUT_SINFO
 	nla_nest_end(msg, sinfoattr);