mac80211: average ack rssi support for data frames

The driver will process the RSSI if available and send it to mac80211.
mac80211 will compute the weighted average of ack RSSI for stations.

Signed-off-by: Balaji Pothunoori <[e-mail]>
Signed-off-by: Johannes Berg <[e-mail]>

net/mac80211/sta_info.c

···
 
 	sta->last_connected = ktime_get_seconds();
 	ewma_signal_init(&sta->rx_stats_avg.signal);
+	ewma_avg_signal_init(&sta->status_stats.avg_ack_signal);
 	for (i = 0; i < ARRAY_SIZE(sta->rx_stats_avg.chain_signal); i++)
 		ewma_signal_init(&sta->rx_stats_avg.chain_signal[i]);
 
···
 	    sta->status_stats.ack_signal_filled) {
 		sinfo->ack_signal = sta->status_stats.last_ack_signal;
 		sinfo->filled |= BIT_ULL(NL80211_STA_INFO_ACK_SIGNAL);
+	}
+
+	if (ieee80211_hw_check(&sta->local->hw, REPORTS_TX_ACK_STATUS) &&
+	    !(sinfo->filled & BIT_ULL(NL80211_STA_INFO_DATA_ACK_SIGNAL_AVG))) {
+		sinfo->avg_ack_signal =
+			-(s8)ewma_avg_signal_read(
+				&sta->status_stats.avg_ack_signal);
+		sinfo->filled |=
+			BIT_ULL(NL80211_STA_INFO_DATA_ACK_SIGNAL_AVG);
 	}
 }
 

net/mac80211/sta_info.h

···
 #define HT_AGG_STATE_START_CB		6
 #define HT_AGG_STATE_STOP_CB		7
 
+DECLARE_EWMA(avg_signal, 10, 8)
 enum ieee80211_agg_stop_reason {
 	AGG_STOP_DECLINED,
 	AGG_STOP_LOCAL_REQUEST,
···
 		unsigned long last_ack;
 		s8 last_ack_signal;
 		bool ack_signal_filled;
+		struct ewma_avg_signal avg_ack_signal;
 	} status_stats;
 
 	/* Updated from TX path only, no locking requirements */

net/mac80211/status.c

···
 			sta->status_stats.last_ack_signal =
 					 (s8)txinfo->status.ack_signal;
 			sta->status_stats.ack_signal_filled = true;
+			ewma_avg_signal_add(&sta->status_stats.avg_ack_signal,
+					    -txinfo->status.ack_signal);
 		}
 	}