diff mbox

mac80211: Track Beacon signal strength and implement cqm events

Message ID 20100330062830.GA4953@jm.kir.nu (mailing list archive)
State Not Applicable, archived
Headers show

Commit Message

Jouni Malinen March 30, 2010, 6:28 a.m. UTC
None
diff mbox

Patch

--- wireless-testing.orig/net/mac80211/debugfs_netdev.c	2010-03-28 11:28:46.000000000 -0700
+++ wireless-testing/net/mac80211/debugfs_netdev.c	2010-03-28 11:42:21.000000000 -0700
@@ -99,6 +99,14 @@  static ssize_t ieee80211_if_fmt_##name(	
 	return scnprintf(buf, buflen, "%pM\n", sdata->field);		\
 }
 
+#define IEEE80211_IF_FMT_DEC_DIV_16(name, field)			\
+static ssize_t ieee80211_if_fmt_##name(					\
+	const struct ieee80211_sub_if_data *sdata,			\
+	char *buf, int buflen)						\
+{									\
+	return scnprintf(buf, buflen, "%d\n", sdata->field / 16);	\
+}
+
 #define __IEEE80211_IF_FILE(name, _write)				\
 static ssize_t ieee80211_if_read_##name(struct file *file,		\
 					char __user *userbuf,		\
@@ -139,6 +147,8 @@  IEEE80211_IF_FILE(rc_rateidx_mask_5ghz, 
 /* STA attributes */
 IEEE80211_IF_FILE(bssid, u.mgd.bssid, MAC);
 IEEE80211_IF_FILE(aid, u.mgd.aid, DEC);
+IEEE80211_IF_FILE(last_beacon, u.mgd.last_beacon_signal, DEC);
+IEEE80211_IF_FILE(ave_beacon, u.mgd.ave_beacon_signal, DEC_DIV_16);
 
 static int ieee80211_set_smps(struct ieee80211_sub_if_data *sdata,
 			      enum ieee80211_smps_mode smps_mode)
@@ -275,6 +285,8 @@  static void add_sta_files(struct ieee802
 
 	DEBUGFS_ADD(bssid);
 	DEBUGFS_ADD(aid);
+	DEBUGFS_ADD(last_beacon);
+	DEBUGFS_ADD(ave_beacon);
 	DEBUGFS_ADD_MODE(smps, 0600);
 }
 
--- wireless-testing.orig/net/mac80211/ieee80211_i.h	2010-03-28 11:17:34.000000000 -0700
+++ wireless-testing/net/mac80211/ieee80211_i.h	2010-03-28 12:10:22.000000000 -0700
@@ -317,6 +317,7 @@  enum ieee80211_sta_flags {
 	IEEE80211_STA_MFP_ENABLED	= BIT(6),
 	IEEE80211_STA_UAPSD_ENABLED	= BIT(7),
 	IEEE80211_STA_NULLFUNC_ACKED	= BIT(8),
+	IEEE80211_STA_RESET_SIGNAL_AVE	= BIT(9),
 };
 
 struct ieee80211_if_managed {
@@ -359,6 +360,24 @@  struct ieee80211_if_managed {
 	int wmm_last_param_set;
 
 	u8 use_4addr;
+
+	/* Signal strength from the last Beacon frame in the current BSS. */
+	int last_beacon_signal;
+
+	/*
+	 * Weighted average of the signal strength from Beacon frames in the
+	 * current BSS. This is in units of 1/16 of the signal unit to maintain
+	 * accuracy and to speed up calculations, i.e., the value need to be
+	 * divided by 16 to get the actual value.
+	 */
+	int ave_beacon_signal;
+
+	/*
+	 * Last Beacon frame signal strength average (ave_beacon_signal / 16)
+	 * that triggered a cqm event. 0 indicates that no event has been
+	 * generated for the current association.
+	 */
+	int last_cqm_event_signal;
 };
 
 enum ieee80211_ibss_request {
--- wireless-testing.orig/net/mac80211/mlme.c	2010-03-28 11:14:11.000000000 -0700
+++ wireless-testing/net/mac80211/mlme.c	2010-03-28 12:36:18.000000000 -0700
@@ -46,6 +46,13 @@ 
  */
 #define IEEE80211_PROBE_WAIT		(HZ / 2)
 
+/*
+ * Weight given to the latest Beacon frame when calculating average signal
+ * strength for Beacon frames received in the current BSS. This must be
+ * between 1 and 15.
+ */
+#define IEEE80211_SIGNAL_AVE_WEIGHT	3
+
 #define TMR_RUNNING_TIMER	0
 #define TMR_RUNNING_CHANSW	1
 
@@ -728,6 +735,8 @@  static void ieee80211_set_associated(str
 	sdata->u.mgd.associated = cbss;
 	memcpy(sdata->u.mgd.bssid, cbss->bssid, ETH_ALEN);
 
+	sdata->u.mgd.flags |= IEEE80211_STA_RESET_SIGNAL_AVE;
+
 	/* just to be sure */
 	sdata->u.mgd.flags &= ~(IEEE80211_STA_CONNECTION_POLL |
 				IEEE80211_STA_BEACON_POLL);
@@ -1343,6 +1352,7 @@  static void ieee80211_rx_mgmt_beacon(str
 				     struct ieee80211_rx_status *rx_status)
 {
 	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
+	struct ieee80211_bss_conf *bss_conf = &sdata->vif.bss_conf;
 	size_t baselen;
 	struct ieee802_11_elems elems;
 	struct ieee80211_local *local = sdata->local;
@@ -1378,6 +1388,41 @@  static void ieee80211_rx_mgmt_beacon(str
 	if (memcmp(bssid, mgmt->bssid, ETH_ALEN) != 0)
 		return;
 
+	/* Track average RSSI from the Beacon frames of the current AP */
+	ifmgd->last_beacon_signal = rx_status->signal;
+	if (ifmgd->flags & IEEE80211_STA_RESET_SIGNAL_AVE) {
+		ifmgd->flags &= ~IEEE80211_STA_RESET_SIGNAL_AVE;
+		ifmgd->ave_beacon_signal = rx_status->signal;
+		ifmgd->last_cqm_event_signal = 0;
+	} else {
+		ifmgd->ave_beacon_signal =
+			(IEEE80211_SIGNAL_AVE_WEIGHT * rx_status->signal * 16 +
+			 (16 - IEEE80211_SIGNAL_AVE_WEIGHT) *
+			 ifmgd->ave_beacon_signal) / 16;
+	}
+	if (bss_conf->cqm_rssi_thold &&
+	    !(local->hw.flags & IEEE80211_HW_SUPPORTS_CQM_RSSI)) {
+		int sig = ifmgd->ave_beacon_signal / 16;
+		int last_event = ifmgd->last_cqm_event_signal;
+		int thold = bss_conf->cqm_rssi_thold;
+		int hyst = bss_conf->cqm_rssi_hyst;
+		if (sig < thold &&
+		    (last_event == 0 || sig < last_event - hyst)) {
+			ifmgd->last_cqm_event_signal = sig;
+			ieee80211_cqm_rssi_notify(
+				&sdata->vif,
+				NL80211_CQM_RSSI_THRESHOLD_EVENT_LOW,
+				GFP_KERNEL);
+		} else if (sig > thold &&
+			   (last_event == 0 || sig > last_event + hyst)) {
+			ifmgd->last_cqm_event_signal = sig;
+			ieee80211_cqm_rssi_notify(
+				&sdata->vif,
+				NL80211_CQM_RSSI_THRESHOLD_EVENT_HIGH,
+				GFP_KERNEL);
+		}
+	}
+
 	if (ifmgd->flags & IEEE80211_STA_BEACON_POLL) {
 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
 		if (net_ratelimit()) {
--- wireless-testing.orig/net/mac80211/cfg.c	2010-03-28 12:05:02.000000000 -0700
+++ wireless-testing/net/mac80211/cfg.c	2010-03-28 12:06:47.000000000 -0700
@@ -1411,9 +1411,6 @@  static int ieee80211_set_cqm_rssi_config
 	struct ieee80211_vif *vif = &sdata->vif;
 	struct ieee80211_bss_conf *bss_conf = &vif->bss_conf;
 
-	if (!(local->hw.flags & IEEE80211_HW_SUPPORTS_CQM_RSSI))
-		return -EOPNOTSUPP;
-
 	if (rssi_thold == bss_conf->cqm_rssi_thold &&
 	    rssi_hyst == bss_conf->cqm_rssi_hyst)
 		return 0;
@@ -1421,6 +1418,12 @@  static int ieee80211_set_cqm_rssi_config
 	bss_conf->cqm_rssi_thold = rssi_thold;
 	bss_conf->cqm_rssi_hyst = rssi_hyst;
 
+	if (!(local->hw.flags & IEEE80211_HW_SUPPORTS_CQM_RSSI)) {
+		if (sdata->vif.type != NL80211_IFTYPE_STATION)
+			return -EOPNOTSUPP;
+		return 0;
+	}
+
 	/* tell the driver upon association, unless already associated */
 	if (sdata->u.mgd.associated)
 		ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_CQM);