3 files changed, 10 insertions, 22 deletions

diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 9482f323fd19..f0aee764d9cd 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -419,6 +419,8 @@ struct ieee80211_sta_tx_tspec {
         bool downgraded;
 };
 
+DECLARE_EWMA(beacon_signal, 16, 4)
+
 struct ieee80211_if_managed {
         struct timer_list timer;
         struct timer_list conn_mon_timer;
@@ -490,13 +492,7 @@ struct ieee80211_if_managed {
 
         s16 p2p_noa_index;
 
-        /*
-         * 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;
+        struct ewma_beacon_signal ave_beacon_signal;
 
         /*
          * Number of Beacon frames used in ave_beacon_signal. This can be used
diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index 79cfc2b35ef0..c7d316b440ef 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -82,13 +82,6 @@ MODULE_PARM_DESC(probe_wait_ms,
                  " before disconnecting (reason 4).");
 
 /*
- * 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
-
-/*
  * How many Beacon frames need to have been used in average signal strength
  * before starting to indicate signal change events.
  */
@@ -3366,21 +3359,19 @@ static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata,
         /* Track average RSSI from the Beacon frames of the current AP */
         if (ifmgd->flags & IEEE80211_STA_RESET_SIGNAL_AVE) {
                 ifmgd->flags &= ~IEEE80211_STA_RESET_SIGNAL_AVE;
-                ifmgd->ave_beacon_signal = rx_status->signal * 16;
+                ewma_beacon_signal_init(&ifmgd->ave_beacon_signal);
                 ifmgd->last_cqm_event_signal = 0;
                 ifmgd->count_beacon_signal = 1;
                 ifmgd->last_ave_beacon_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;
                 ifmgd->count_beacon_signal++;
         }
 
+        ewma_beacon_signal_add(&ifmgd->ave_beacon_signal, -rx_status->signal);
+
         if (ifmgd->rssi_min_thold != ifmgd->rssi_max_thold &&
             ifmgd->count_beacon_signal >= IEEE80211_SIGNAL_AVE_MIN_COUNT) {
-                int sig = ifmgd->ave_beacon_signal / 16;
+                int sig = -ewma_beacon_signal_read(&ifmgd->ave_beacon_signal);
                 int last_sig = ifmgd->last_ave_beacon_signal;
                 struct ieee80211_event event = {
                         .type = RSSI_EVENT,
@@ -3407,10 +3398,11 @@ static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata,
         if (bss_conf->cqm_rssi_thold &&
             ifmgd->count_beacon_signal >= IEEE80211_SIGNAL_AVE_MIN_COUNT &&
             !(sdata->vif.driver_flags & IEEE80211_VIF_SUPPORTS_CQM_RSSI)) {
-                int sig = ifmgd->ave_beacon_signal / 16;
+                int sig = -ewma_beacon_signal_read(&ifmgd->ave_beacon_signal);
                 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;
diff --git a/net/mac80211/util.c b/net/mac80211/util.c
index f16705675339..9cabf076d718 100644
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -2543,7 +2543,7 @@ int ieee80211_ave_rssi(struct ieee80211_vif *vif)
                 /* non-managed type inferfaces */
                 return 0;
         }
-        return ifmgd->ave_beacon_signal / 16;
+        return -ewma_beacon_signal_read(&ifmgd->ave_beacon_signal);
 }
 EXPORT_SYMBOL_GPL(ieee80211_ave_rssi);