mac80211: track needed RX chains for channel contexts

On each channel that the device is operating on, it
may need to listen using one or more chains depending
on the SMPS settings of the interfaces using it. The
previous channel context changes completely removed
this ability (before, it was available as the SMPS
mode).

Add per-context tracking of the required static and
dynamic RX chains and notify the driver on changes.
To achieve this, track the chains and SMPS mode used
on each virtual interface and update the channel
context whenever this changes.

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

1 files changed, 27 insertions, 55 deletions

diff --git a/net/mac80211/util.c b/net/mac80211/util.c
index 7d737071dedb..b732e219b107 100644
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -1618,68 +1618,24 @@ void ieee80211_resume_disconnect(struct ieee80211_vif *vif)
 }
 EXPORT_SYMBOL_GPL(ieee80211_resume_disconnect);
 
-static int check_mgd_smps(struct ieee80211_if_managed *ifmgd,
-			  enum ieee80211_smps_mode *smps_mode)
+void ieee80211_recalc_smps(struct ieee80211_sub_if_data *sdata)
 {
-	if (ifmgd->associated) {
-		*smps_mode = ifmgd->ap_smps;
-
-		if (*smps_mode == IEEE80211_SMPS_AUTOMATIC) {
-			if (ifmgd->powersave)
-				*smps_mode = IEEE80211_SMPS_DYNAMIC;
-			else
-				*smps_mode = IEEE80211_SMPS_OFF;
-		}
-
-		return 1;
-	}
-
-	return 0;
-}
-
-void ieee80211_recalc_smps(struct ieee80211_local *local)
-{
-	struct ieee80211_sub_if_data *sdata;
-	enum ieee80211_smps_mode smps_mode = IEEE80211_SMPS_OFF;
-	int count = 0;
-
-	mutex_lock(&local->iflist_mtx);
-
-	/*
-	 * This function could be improved to handle multiple
-	 * interfaces better, but right now it makes any
-	 * non-station interfaces force SM PS to be turned
-	 * off. If there are multiple station interfaces it
-	 * could also use the best possible mode, e.g. if
-	 * one is in static and the other in dynamic then
-	 * dynamic is ok.
-	 */
-
-	list_for_each_entry(sdata, &local->interfaces, list) {
-		if (!ieee80211_sdata_running(sdata))
-			continue;
-		if (sdata->vif.type == NL80211_IFTYPE_P2P_DEVICE)
-			continue;
-		if (sdata->vif.type != NL80211_IFTYPE_STATION)
-			goto set;
+	struct ieee80211_local *local = sdata->local;
+	struct ieee80211_chanctx_conf *chanctx_conf;
+	struct ieee80211_chanctx *chanctx;
 
-		count += check_mgd_smps(&sdata->u.mgd, &smps_mode);
+	mutex_lock(&local->chanctx_mtx);
 
-		if (count > 1) {
-			smps_mode = IEEE80211_SMPS_OFF;
-			break;
-		}
-	}
+	chanctx_conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
+					lockdep_is_held(&local->chanctx_mtx));
 
-	if (smps_mode == local->smps_mode)
+	if (WARN_ON_ONCE(!chanctx_conf))
 		goto unlock;
 
- set:
-	local->smps_mode = smps_mode;
-	/* changed flag is auto-detected for this */
-	ieee80211_hw_config(local, 0);
+	chanctx = container_of(chanctx_conf, struct ieee80211_chanctx, conf);
+	ieee80211_recalc_smps_chanctx(local, chanctx);
  unlock:
-	mutex_unlock(&local->iflist_mtx);
+	mutex_unlock(&local->chanctx_mtx);
 }
 
 static bool ieee80211_id_in_list(const u8 *ids, int n_ids, u8 id)
@@ -1978,3 +1934,19 @@ int ieee80211_ave_rssi(struct ieee80211_vif *vif)
 	return ifmgd->ave_beacon_signal;
 }
 EXPORT_SYMBOL_GPL(ieee80211_ave_rssi);
+
+u8 ieee80211_mcs_to_chains(const struct ieee80211_mcs_info *mcs)
+{
+	if (!mcs)
+		return 1;
+
+	/* TODO: consider rx_highest */
+
+	if (mcs->rx_mask[3])
+		return 4;
+	if (mcs->rx_mask[2])
+		return 3;
+	if (mcs->rx_mask[1])
+		return 2;
+	return 1;
+}