mac80211: handle VHT operating mode notification

Handle the operating mode notification action frame.
When the supported streams or the bandwidth change
let the driver and rate control algorithm know.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

include/linux/ieee80211.h

@@ -1301,6 +1301,7 @@ struct ieee80211_vht_operation {
 #define IEEE80211_VHT_CAP_MAX_MPDU_LENGTH_11454			0x00000002
 #define IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160MHZ		0x00000004
 #define IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ	0x00000008
+#define IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK			0x0000000C
 #define IEEE80211_VHT_CAP_RXLDPC				0x00000010
 #define IEEE80211_VHT_CAP_SHORT_GI_80				0x00000020
 #define IEEE80211_VHT_CAP_SHORT_GI_160				0x00000040

include/net/mac80211.h

@@ -2118,11 +2118,14 @@ enum ieee80211_frame_release_type {
  * @IEEE80211_RC_SUPP_RATES_CHANGED: The supported rate set of this peer
  *	changed (in IBSS mode) due to discovering more information about
  *	the peer.
+ * @IEEE80211_RC_NSS_CHANGED: N_SS (number of spatial streams) was changed
+ *	by the peer
  */
 enum ieee80211_rate_control_changed {
 	IEEE80211_RC_BW_CHANGED		= BIT(0),
 	IEEE80211_RC_SMPS_CHANGED	= BIT(1),
 	IEEE80211_RC_SUPP_RATES_CHANGED	= BIT(2),
+	IEEE80211_RC_NSS_CHANGED	= BIT(3),
 };
 
 /**

net/mac80211/ht.c

@@ -212,6 +212,10 @@ bool ieee80211_ht_cap_ie_to_sta_ht_cap(struct ieee80211_sub_if_data *sdata,
 		changed = true;
 	sta->sta.bandwidth = bw;
 
+	sta->cur_max_bandwidth =
+		ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40 ?
+				IEEE80211_STA_RX_BW_40 : IEEE80211_STA_RX_BW_20;
+
 	return changed;
 }
 

net/mac80211/ieee80211_i.h

@@ -1433,6 +1433,9 @@ void ieee80211_vht_cap_ie_to_sta_vht_cap(struct ieee80211_sub_if_data *sdata,
 					 struct sta_info *sta);
 enum ieee80211_sta_rx_bandwidth ieee80211_sta_cur_vht_bw(struct sta_info *sta);
 void ieee80211_sta_set_rx_nss(struct sta_info *sta);
+void ieee80211_vht_handle_opmode(struct ieee80211_sub_if_data *sdata,
+				 struct sta_info *sta, u8 opmode,
+				 enum ieee80211_band band);
 
 /* Spectrum management */
 void ieee80211_process_measurement_req(struct ieee80211_sub_if_data *sdata,

net/mac80211/rx.c

@@ -2435,6 +2435,36 @@ ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
 			goto invalid;
 		}
 
+		break;
+	case WLAN_CATEGORY_VHT:
+		if (sdata->vif.type != NL80211_IFTYPE_STATION &&
+		    sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
+		    sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
+		    sdata->vif.type != NL80211_IFTYPE_AP &&
+		    sdata->vif.type != NL80211_IFTYPE_ADHOC)
+			break;
+
+		/* verify action code is present */
+		if (len < IEEE80211_MIN_ACTION_SIZE + 1)
+			goto invalid;
+
+		switch (mgmt->u.action.u.vht_opmode_notif.action_code) {
+		case WLAN_VHT_ACTION_OPMODE_NOTIF: {
+			u8 opmode;
+
+			/* verify opmode is present */
+			if (len < IEEE80211_MIN_ACTION_SIZE + 2)
+				goto invalid;
+
+			opmode = mgmt->u.action.u.vht_opmode_notif.operating_mode;
+
+			ieee80211_vht_handle_opmode(rx->sdata, rx->sta,
+						    opmode, status->band);
+			goto handled;
+		}
+		default:
+			break;
+		}
 		break;
 	case WLAN_CATEGORY_BACK:
 		if (sdata->vif.type != NL80211_IFTYPE_STATION &&

net/mac80211/sta_info.h

@@ -297,6 +297,8 @@ struct sta_ampdu_mlme {
  * @sta_state: duplicates information about station state (for debug)
  * @beacon_loss_count: number of times beacon loss has triggered
  * @rcu_head: RCU head used for freeing this station struct
+ * @cur_max_bandwidth: maximum bandwidth to use for TX to the station,
+ *	taken from HT/VHT capabilities or VHT operating mode notification
  */
 struct sta_info {
 	/* General information, mostly static */
@@ -398,6 +400,8 @@ struct sta_info {
 	} debugfs;
 #endif
 
+	enum ieee80211_sta_rx_bandwidth cur_max_bandwidth;
+
 	unsigned int lost_packets;
 	unsigned int beacon_loss_count;
 

net/mac80211/vht.c

@@ -10,6 +10,7 @@
 #include <linux/export.h>
 #include <net/mac80211.h>
 #include "ieee80211_i.h"
+#include "rate.h"
 
 
 void ieee80211_vht_cap_ie_to_sta_vht_cap(struct ieee80211_sub_if_data *sdata,
@@ -39,19 +40,29 @@ void ieee80211_vht_cap_ie_to_sta_vht_cap(struct ieee80211_sub_if_data *sdata,
 	memcpy(&vht_cap->vht_mcs, &vht_cap_ie->supp_mcs,
 	       sizeof(struct ieee80211_vht_mcs_info));
 
+	switch (vht_cap->cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK) {
+	case IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160MHZ:
+	case IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ:
+		sta->cur_max_bandwidth = IEEE80211_STA_RX_BW_160;
+		break;
+	default:
+		sta->cur_max_bandwidth = IEEE80211_STA_RX_BW_80;
+	}
+
 	sta->sta.bandwidth = ieee80211_sta_cur_vht_bw(sta);
 }
 
 enum ieee80211_sta_rx_bandwidth ieee80211_sta_cur_vht_bw(struct sta_info *sta)
 {
 	struct ieee80211_sub_if_data *sdata = sta->sdata;
 	u32 cap = sta->sta.vht_cap.cap;
+	enum ieee80211_sta_rx_bandwidth bw;
 
-	if (!sta->sta.vht_cap.vht_supported)
-		return sta->sta.ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40 ?
+	if (!sta->sta.vht_cap.vht_supported) {
+		bw = sta->sta.ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40 ?
 				IEEE80211_STA_RX_BW_40 : IEEE80211_STA_RX_BW_20;
-
-	/* TODO: handle VHT opmode notification data */
+		goto check_max;
+	}
 
 	switch (sdata->vif.bss_conf.chandef.width) {
 	default:
@@ -60,19 +71,31 @@ enum ieee80211_sta_rx_bandwidth ieee80211_sta_cur_vht_bw(struct sta_info *sta)
 	case NL80211_CHAN_WIDTH_20_NOHT:
 	case NL80211_CHAN_WIDTH_20:
 	case NL80211_CHAN_WIDTH_40:
-		return sta->sta.ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40 ?
+		bw = sta->sta.ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40 ?
 				IEEE80211_STA_RX_BW_40 : IEEE80211_STA_RX_BW_20;
+		break;
 	case NL80211_CHAN_WIDTH_160:
-		if (cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160MHZ)
-			return IEEE80211_STA_RX_BW_160;
+		if ((cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK) ==
+				IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160MHZ) {
+			bw = IEEE80211_STA_RX_BW_160;
+			break;
+		}
 		/* fall through */
 	case NL80211_CHAN_WIDTH_80P80:
-		if (cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ)
-			return IEEE80211_STA_RX_BW_160;
+		if ((cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK) ==
+				IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ) {
+			bw = IEEE80211_STA_RX_BW_160;
+			break;
+		}
 		/* fall through */
 	case NL80211_CHAN_WIDTH_80:
-		return IEEE80211_STA_RX_BW_80;
+		bw = IEEE80211_STA_RX_BW_80;
 	}
+
+ check_max:
+	if (bw > sta->cur_max_bandwidth)
+		bw = sta->cur_max_bandwidth;
+	return bw;
 }
 
 void ieee80211_sta_set_rx_nss(struct sta_info *sta)
@@ -115,3 +138,53 @@ void ieee80211_sta_set_rx_nss(struct sta_info *sta)
 	ht_rx_nss = max(ht_rx_nss, vht_rx_nss);
 	sta->sta.rx_nss = max_t(u8, 1, ht_rx_nss);
 }
+
+void ieee80211_vht_handle_opmode(struct ieee80211_sub_if_data *sdata,
+				 struct sta_info *sta, u8 opmode,
+				 enum ieee80211_band band)
+{
+	struct ieee80211_local *local = sdata->local;
+	struct ieee80211_supported_band *sband;
+	enum ieee80211_sta_rx_bandwidth new_bw;
+	u32 changed = 0;
+	u8 nss;
+
+	sband = local->hw.wiphy->bands[band];
+
+	/* ignore - no support for BF yet */
+	if (opmode & IEEE80211_OPMODE_NOTIF_RX_NSS_TYPE_BF)
+		return;
+
+	nss = opmode & IEEE80211_OPMODE_NOTIF_RX_NSS_MASK;
+	nss >>= IEEE80211_OPMODE_NOTIF_RX_NSS_SHIFT;
+	nss += 1;
+
+	if (sta->sta.rx_nss != nss) {
+		sta->sta.rx_nss = nss;
+		changed |= IEEE80211_RC_NSS_CHANGED;
+	}
+
+	switch (opmode & IEEE80211_OPMODE_NOTIF_CHANWIDTH_MASK) {
+	case IEEE80211_OPMODE_NOTIF_CHANWIDTH_20MHZ:
+		sta->cur_max_bandwidth = IEEE80211_STA_RX_BW_20;
+		break;
+	case IEEE80211_OPMODE_NOTIF_CHANWIDTH_40MHZ:
+		sta->cur_max_bandwidth = IEEE80211_STA_RX_BW_40;
+		break;
+	case IEEE80211_OPMODE_NOTIF_CHANWIDTH_80MHZ:
+		sta->cur_max_bandwidth = IEEE80211_STA_RX_BW_80;
+		break;
+	case IEEE80211_OPMODE_NOTIF_CHANWIDTH_160MHZ:
+		sta->cur_max_bandwidth = IEEE80211_STA_RX_BW_160;
+		break;
+	}
+
+	new_bw = ieee80211_sta_cur_vht_bw(sta);
+	if (new_bw != sta->sta.bandwidth) {
+		sta->sta.bandwidth = new_bw;
+		changed |= IEEE80211_RC_NSS_CHANGED;
+	}
+
+	if (changed)
+		rate_control_rate_update(local, sband, sta, changed);
+}