mac80211: let drivers inform it about per TID buffered frames

For uAPSD implementation, it is necessary to know on
which ACs frames are buffered. mac80211 obviously
knows about the frames it has buffered itself, but
with aggregation many drivers buffer frames. Thus,
mac80211 needs to be informed about this.

For now, since we don't have APSD in any form, this
will unconditionally set the TIM bit for the station
but later with uAPSD only some ACs might cause the
TIM bit to be set.

ath9k is the only driver using this API and I only
modify it in the most basic way, it won't be able
to implement uAPSD with this yet. But it can't do
that anyway since there's no way to selectively
release frames to the peer yet.

Since drivers will buffer frames per TID, let them
inform mac80211 on a per TID basis, mac80211 will
then sort out the AC mapping itself.

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

1 files changed, 6 insertions, 2 deletions

diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c
index c52e58c..016742d 100644
--- a/net/mac80211/sta_info.c
+++ b/net/mac80211/sta_info.c
@@ -1117,11 +1117,15 @@ void ieee80211_sta_block_awake(struct ieee80211_hw *hw,
 }
 EXPORT_SYMBOL(ieee80211_sta_block_awake);
 
-void ieee80211_sta_set_tim(struct ieee80211_sta *pubsta)
+void ieee80211_sta_set_buffered(struct ieee80211_sta *pubsta,
+				u8 tid, bool buffered)
 {
 	struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
 
+	if (!buffered)
+		return;
+
 	set_sta_flags(sta, WLAN_STA_PS_DRIVER_BUF);
 	sta_info_set_tim_bit(sta);
 }
-EXPORT_SYMBOL(ieee80211_sta_set_tim);
+EXPORT_SYMBOL(ieee80211_sta_set_buffered);