mac80211: calculate max RX NSS for EHT mode

If the station supports EHT mode, calculate the maximum RX NSS
from EHT station capabilities.
Signed-off-by: Mordechay Goodstein <mordechay.goodstein@intel.com>
Link: https://lore.kernel.org/r/20220214173004.cf61972c8919.I54f5a416f0789bf4eefad04703d941b6755f6dd6@changeidSigned-off-by: Johannes Berg <johannes.berg@intel.com>

net/mac80211/vht.c

@@ -497,13 +497,24 @@ enum ieee80211_sta_rx_bandwidth ieee80211_sta_cur_vht_bw(struct sta_info *sta)
 
 void ieee80211_sta_set_rx_nss(struct sta_info *sta)
 {
-	u8 ht_rx_nss = 0, vht_rx_nss = 0, he_rx_nss = 0, rx_nss;
+	u8 ht_rx_nss = 0, vht_rx_nss = 0, he_rx_nss = 0, eht_rx_nss = 0, rx_nss;
 	bool support_160;
 
 	/* if we received a notification already don't overwrite it */
 	if (sta->sta.rx_nss)
 		return;
 
+	if (sta->sta.eht_cap.has_eht) {
+		int i;
+		const u8 *rx_nss_mcs = (void *)&sta->sta.eht_cap.eht_mcs_nss_supp;
+
+		/* get the max nss for EHT over all possible bandwidths and mcs */
+		for (i = 0; i < sizeof(struct ieee80211_eht_mcs_nss_supp); i++)
+			eht_rx_nss = max_t(u8, eht_rx_nss,
+					   u8_get_bits(rx_nss_mcs[i],
+						       IEEE80211_EHT_MCS_NSS_RX));
+	}
+
 	if (sta->sta.he_cap.has_he) {
 		int i;
 		u8 rx_mcs_80 = 0, rx_mcs_160 = 0;
@@ -569,6 +580,7 @@ void ieee80211_sta_set_rx_nss(struct sta_info *sta)
 
 	rx_nss = max(vht_rx_nss, ht_rx_nss);
 	rx_nss = max(he_rx_nss, rx_nss);
+	rx_nss = max(eht_rx_nss, rx_nss);
 	sta->sta.rx_nss = max_t(u8, 1, rx_nss);
 }