mac80211: TDLS: correctly configure SMPS state

The IEEE802.11-2012 specification is vague regarding SMPS operation during
TDLS. It does not define a clear way to transition between SMPS states.

To avoid interop issues, set SMPS to off when TDLS peers are connected.
Accomplish this by extending the definition of the AUTOMATIC state. If the
driver forces a state other than OFF, disconnect all TDLS peers.

While at it, avoid changing the SMPS state of the peer STA. We have no
way to control it, so try and behave correctly towards it.

Move the TDLS peer-teardown function to where the rest of the TDLS code
resides.

Signed-off-by: Arik Nemtsov <arikx.nemtsov@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 32 insertions, 4 deletions

diff --git a/net/mac80211/tdls.c b/net/mac80211/tdls.c
index fb846cb047d6..8536789da17d 100644
--- a/net/mac80211/tdls.c
+++ b/net/mac80211/tdls.c
@@ -4,6 +4,7 @@
  * Copyright 2006-2010	Johannes Berg <johannes@sipsolutions.net>
  * Copyright 2014, Intel Corporation
  * Copyright 2014  Intel Mobile Communications GmbH
+ * Copyright 2015  Intel Deutschland GmbH
  *
  * This file is GPLv2 as found in COPYING.
  */
@@ -448,10 +449,6 @@ ieee80211_tdls_add_setup_start_ies(struct ieee80211_sub_if_data *sdata,
 		ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
 	} else if (action_code == WLAN_TDLS_SETUP_RESPONSE &&
 		   ht_cap.ht_supported && sta->sta.ht_cap.ht_supported) {
-		/* disable SMPS in TDLS responder */
-		sta->sta.ht_cap.cap |= WLAN_HT_CAP_SM_PS_DISABLED
-					<< IEEE80211_HT_CAP_SM_PS_SHIFT;
-
 		/* the peer caps are already intersected with our own */
 		memcpy(&ht_cap, &sta->sta.ht_cap, sizeof(ht_cap));
 
@@ -1063,8 +1060,17 @@ ieee80211_tdls_mgmt_setup(struct wiphy *wiphy, struct net_device *dev,
 {
 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 	struct ieee80211_local *local = sdata->local;
+	enum ieee80211_smps_mode smps_mode = sdata->u.mgd.driver_smps_mode;
 	int ret;
 
+	/* don't support setup with forced SMPS mode that's not off */
+	if (smps_mode != IEEE80211_SMPS_AUTOMATIC &&
+	    smps_mode != IEEE80211_SMPS_OFF) {
+		tdls_dbg(sdata, "Aborting TDLS setup due to SMPS mode %d\n",
+			 smps_mode);
+		return -ENOTSUPP;
+	}
+
 	mutex_lock(&local->mtx);
 
 	/* we don't support concurrent TDLS peer setups */
@@ -1323,6 +1329,10 @@ int ieee80211_tdls_oper(struct wiphy *wiphy, struct net_device *dev,
 		eth_zero_addr(sdata->u.mgd.tdls_peer);
 	}
 
+	if (ret == 0)
+		ieee80211_queue_work(&sdata->local->hw,
+				     &sdata->u.mgd.request_smps_work);
+
 	mutex_unlock(&local->mtx);
 	return ret;
 }
@@ -1819,3 +1829,21 @@ void ieee80211_process_tdls_channel_switch(struct ieee80211_sub_if_data *sdata,
 		return;
 	}
 }
+
+void ieee80211_teardown_tdls_peers(struct ieee80211_sub_if_data *sdata)
+{
+	struct sta_info *sta;
+	u16 reason = WLAN_REASON_TDLS_TEARDOWN_UNSPECIFIED;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(sta, &sdata->local->sta_list, list) {
+		if (!sta->sta.tdls || sta->sdata != sdata || !sta->uploaded ||
+		    !test_sta_flag(sta, WLAN_STA_AUTHORIZED))
+			continue;
+
+		ieee80211_tdls_oper_request(&sdata->vif, sta->sta.addr,
+					    NL80211_TDLS_TEARDOWN, reason,
+					    GFP_ATOMIC);
+	}
+	rcu_read_unlock();
+}