openwrtv4/package/iw/patches/110-per_chain_signal_strength.patch

--- a/station.c
+++ b/station.c
@@ -61,6 +61,33 @@ static void print_sta_bitrate(struct nla
 	}
 }
 
+static char *get_chain_signal(struct nlattr *attr_list)
+{
+	struct nlattr *attr;
+	static char buf[64];
+	char *cur = buf;
+	int i = 0, rem;
+	const char *prefix;
+
+	if (!attr_list)
+		return "";
+
+	nla_for_each_nested(attr, attr_list, rem) {
+		if (i++ > 0)
+			prefix = ", ";
+		else
+			prefix = "[";
+
+		cur += snprintf(cur, sizeof(buf) - (cur - buf), "%s%d", prefix,
+				(int8_t) nla_get_u8(attr));
+	}
+
+	if (i)
+		snprintf(cur, sizeof(buf) - (cur - buf), "] ");
+
+	return buf;
+}
+
 static int print_sta_handler(struct nl_msg *msg, void *arg)
 {
 	struct nlattr *tb[NL80211_ATTR_MAX + 1];
@@ -84,7 +111,10 @@ static int print_sta_handler(struct nl_m
 		[NL80211_STA_INFO_TX_FAILED] = { .type = NLA_U32 },
 		[NL80211_STA_INFO_STA_FLAGS] =
 			{ .minlen = sizeof(struct nl80211_sta_flag_update) },
+		[NL80211_STA_INFO_CHAIN_SIGNAL] = { .type = NLA_NESTED },
+		[NL80211_STA_INFO_CHAIN_SIGNAL_AVG] = { .type = NLA_NESTED },
 	};
+	char *chain;
 
 	nla_parse(tb, NL80211_ATTR_MAX, genlmsg_attrdata(gnlh, 0),
 		  genlmsg_attrlen(gnlh, 0), NULL);
@@ -131,12 +161,18 @@ static int print_sta_handler(struct nl_m
 	if (sinfo[NL80211_STA_INFO_TX_FAILED])
 		printf("\n\ttx failed:\t%u",
 			nla_get_u32(sinfo[NL80211_STA_INFO_TX_FAILED]));
+
+	chain = get_chain_signal(sinfo[NL80211_STA_INFO_CHAIN_SIGNAL]);
 	if (sinfo[NL80211_STA_INFO_SIGNAL])
-		printf("\n\tsignal:  \t%d dBm",
-			(int8_t)nla_get_u8(sinfo[NL80211_STA_INFO_SIGNAL]));
+		printf("\n\tsignal:  \t%d %sdBm",
+			(int8_t)nla_get_u8(sinfo[NL80211_STA_INFO_SIGNAL]),
+			chain);
+
+	chain = get_chain_signal(sinfo[NL80211_STA_INFO_CHAIN_SIGNAL_AVG]);
 	if (sinfo[NL80211_STA_INFO_SIGNAL_AVG])
-		printf("\n\tsignal avg:\t%d dBm",
-			(int8_t)nla_get_u8(sinfo[NL80211_STA_INFO_SIGNAL_AVG]));
+		printf("\n\tsignal avg:\t%d %sdBm",
+			(int8_t)nla_get_u8(sinfo[NL80211_STA_INFO_SIGNAL_AVG]),
+			chain);
 
 	print_sta_bitrate(sinfo[NL80211_STA_INFO_TX_BITRATE], "tx bitrate");
 	print_sta_bitrate(sinfo[NL80211_STA_INFO_RX_BITRATE], "rx bitrate");