mac80211: handle SMPS action frames

When a peer changes SMPS state we should update
rate control so it doesn't have to detect it by
itself. It can't detect "dynamic" mode anyway
since that just requires rts-cts handshaking.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

include/net/mac80211.h

@@ -3502,9 +3502,12 @@ void ieee80211_send_bar(struct ieee80211_vif *vif, u8 *ra, u16 tid, u16 ssn);
  *
  * @IEEE80211_RC_HT_CHANGED: The HT parameters of the operating channel have
  *	changed, rate control algorithm can update its internal state if needed.
+ * @IEEE80211_RC_SMPS_CHANGED: The SMPS state of the station changed, the rate
+ *	control algorithm needs to adjust accordingly.
  */
 enum rate_control_changed {
-	IEEE80211_RC_HT_CHANGED = BIT(0)
+	IEEE80211_RC_HT_CHANGED		= BIT(0),
+	IEEE80211_RC_SMPS_CHANGED	= BIT(1),
 };
 
 /**

net/mac80211/rx.c

@@ -28,6 +28,7 @@
 #include "wpa.h"
 #include "tkip.h"
 #include "wme.h"
+#include "rate.h"
 
 /*
  * monitor mode reception
@@ -2233,6 +2234,63 @@ ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
 		return RX_DROP_UNUSABLE;
 
 	switch (mgmt->u.action.category) {
+	case WLAN_CATEGORY_HT:
+		/* reject HT action frames from stations not supporting HT */
+		if (!rx->sta->sta.ht_cap.ht_supported)
+			goto invalid;
+
+		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 & smps_control are present */
+		if (len < IEEE80211_MIN_ACTION_SIZE + 2)
+			goto invalid;
+
+		switch (mgmt->u.action.u.ht_smps.action) {
+		case WLAN_HT_ACTION_SMPS: {
+			struct ieee80211_supported_band *sband;
+			u8 smps;
+
+			/* convert to HT capability */
+			switch (mgmt->u.action.u.ht_smps.smps_control) {
+			case WLAN_HT_SMPS_CONTROL_DISABLED:
+				smps = WLAN_HT_CAP_SM_PS_DISABLED;
+				break;
+			case WLAN_HT_SMPS_CONTROL_STATIC:
+				smps = WLAN_HT_CAP_SM_PS_STATIC;
+				break;
+			case WLAN_HT_SMPS_CONTROL_DYNAMIC:
+				smps = WLAN_HT_CAP_SM_PS_DYNAMIC;
+				break;
+			default:
+				goto invalid;
+			}
+			smps <<= IEEE80211_HT_CAP_SM_PS_SHIFT;
+
+			/* if no change do nothing */
+			if ((rx->sta->sta.ht_cap.cap &
+					IEEE80211_HT_CAP_SM_PS) == smps)
+				goto handled;
+
+			rx->sta->sta.ht_cap.cap &= ~IEEE80211_HT_CAP_SM_PS;
+			rx->sta->sta.ht_cap.cap |= smps;
+
+			sband = rx->local->hw.wiphy->bands[status->band];
+
+			rate_control_rate_update(local, sband, rx->sta,
+						 IEEE80211_RC_SMPS_CHANGED,
+						 local->_oper_channel_type);
+			goto handled;
+		}
+		default:
+			goto invalid;
+		}
+
+		break;
 	case WLAN_CATEGORY_BACK:
 		if (sdata->vif.type != NL80211_IFTYPE_STATION &&
 		    sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&