mac80211: enable spatial multiplexing powersave

Enable spatial multiplexing in mac80211 by telling the
driver what to do and, where necessary, sending action
frames to the AP to update the requested SMPS mode.

Also includes a trivial implementation for hwsim that
just logs the requested mode.

For now, the userspace interface is in debugfs only,
and let you toggle the requested mode at any time.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 24 insertions, 0 deletions

diff --git a/net/mac80211/main.c b/net/mac80211/main.c
index 98320a9..e1293e8 100644
--- a/net/mac80211/main.c
+++ b/net/mac80211/main.c
@@ -113,6 +113,18 @@ int ieee80211_hw_config(struct ieee80211_local *local, u32 changed)
 		changed |= IEEE80211_CONF_CHANGE_CHANNEL;
 	}
 
+	if (!conf_is_ht(&local->hw.conf)) {
+		/*
+		 * mac80211.h documents that this is only valid
+		 * when the channel is set to an HT type, and
+		 * that otherwise STATIC is used.
+		 */
+		local->hw.conf.smps_mode = IEEE80211_SMPS_STATIC;
+	} else if (local->hw.conf.smps_mode != local->smps_mode) {
+		local->hw.conf.smps_mode = local->smps_mode;
+		changed |= IEEE80211_CONF_CHANGE_SMPS;
+	}
+
 	if (scan_chan)
 		power = chan->max_power;
 	else
@@ -297,6 +309,16 @@ void ieee80211_restart_hw(struct ieee80211_hw *hw)
 }
 EXPORT_SYMBOL(ieee80211_restart_hw);
 
+static void ieee80211_recalc_smps_work(struct work_struct *work)
+{
+	struct ieee80211_local *local =
+		container_of(work, struct ieee80211_local, recalc_smps);
+
+	mutex_lock(&local->iflist_mtx);
+	ieee80211_recalc_smps(local, NULL);
+	mutex_unlock(&local->iflist_mtx);
+}
+
 struct ieee80211_hw *ieee80211_alloc_hw(size_t priv_data_len,
 					const struct ieee80211_ops *ops)
 {
@@ -370,6 +392,8 @@ struct ieee80211_hw *ieee80211_alloc_hw(size_t priv_data_len,
 	INIT_WORK(&local->restart_work, ieee80211_restart_work);
 
 	INIT_WORK(&local->reconfig_filter, ieee80211_reconfig_filter);
+	INIT_WORK(&local->recalc_smps, ieee80211_recalc_smps_work);
+	local->smps_mode = IEEE80211_SMPS_OFF;
 
 	INIT_WORK(&local->dynamic_ps_enable_work,
 		  ieee80211_dynamic_ps_enable_work);