mac80211: allow drivers to set default uAPSD parameters

mac80211 currently sets uAPSD parameters to have VO AC trigger-
and delivery-enabled, with maximum service period length.

Allow drivers to change these default settings since different
uAPSD client implementations may handle errors differently and
be able to recover from some errors.

Note: some APs may not function correctly if one or all ACs are
trigger- and delivery-enabled, see
http://thread.gmane.org/gmane.linux.kernel.wireless.general/93577.
We retested with this AP and later firmware doesn't have this
bug any more.

Signed-off-by: Alexander Bondar <alexander.bondar@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

include/net/mac80211.h

@@ -1534,6 +1534,17 @@ enum ieee80211_hw_flags {
  * @netdev_features: netdev features to be set in each netdev created
  *	from this HW. Note only HW checksum features are currently
  *	compatible with mac80211. Other feature bits will be rejected.
+ *
+ * @uapsd_queues: This bitmap is included in (re)association frame to indicate
+ *	for each access category if it is uAPSD trigger-enabled and delivery-
+ *	enabled. Use IEEE80211_WMM_IE_STA_QOSINFO_AC_* to set this bitmap.
+ *	Each bit corresponds to different AC. Value '1' in specific bit means
+ *	that corresponding AC is both trigger- and delivery-enabled. '0' means
+ *	neither enabled.
+ *
+ * @uapsd_max_sp_len: maximum number of total buffered frames the WMM AP may
+ *	deliver to a WMM STA during any Service Period triggered by the WMM STA.
+ *	Use IEEE80211_WMM_IE_STA_QOSINFO_SP_* for correct values.
  */
 struct ieee80211_hw {
 	struct ieee80211_conf conf;
@@ -1559,6 +1570,8 @@ struct ieee80211_hw {
 	u8 radiotap_mcs_details;
 	u16 radiotap_vht_details;
 	netdev_features_t netdev_features;
+	u8 uapsd_queues;
+	u8 uapsd_max_sp_len;
 };
 
 /**

net/mac80211/main.c

@@ -587,6 +587,8 @@ struct ieee80211_hw *ieee80211_alloc_hw(size_t priv_data_len,
 					 IEEE80211_RADIOTAP_MCS_HAVE_BW;
 	local->hw.radiotap_vht_details = IEEE80211_RADIOTAP_VHT_KNOWN_GI |
 					 IEEE80211_RADIOTAP_VHT_KNOWN_BANDWIDTH;
+	local->hw.uapsd_queues = IEEE80211_DEFAULT_UAPSD_QUEUES;
+	local->hw.uapsd_max_sp_len = IEEE80211_DEFAULT_MAX_SP_LEN;
 	local->user_power_level = IEEE80211_UNSET_POWER_LEVEL;
 	wiphy->ht_capa_mod_mask = &mac80211_ht_capa_mod_mask;
 	wiphy->vht_capa_mod_mask = &mac80211_vht_capa_mod_mask;

net/mac80211/mlme.c

@@ -3525,8 +3525,8 @@ void ieee80211_sta_setup_sdata(struct ieee80211_sub_if_data *sdata)
 
 	ifmgd->flags = 0;
 	ifmgd->powersave = sdata->wdev.ps;
-	ifmgd->uapsd_queues = IEEE80211_DEFAULT_UAPSD_QUEUES;
-	ifmgd->uapsd_max_sp_len = IEEE80211_DEFAULT_MAX_SP_LEN;
+	ifmgd->uapsd_queues = sdata->local->hw.uapsd_queues;
+	ifmgd->uapsd_max_sp_len = sdata->local->hw.uapsd_max_sp_len;
 	ifmgd->p2p_noa_index = -1;
 
 	mutex_init(&ifmgd->mtx);