mac80211: explicitly notify drivers of frame release

iwlwifi needs to know the number of frames that are
going to be sent to a station while it is asleep so
it can properly handle the uCode blocking of that
station.

Before uAPSD, we got by by telling the device that
a single frame was going to be released whenever we
encountered IEEE80211_TX_CTL_POLL_RESPONSE. With
uAPSD, however, that is no longer possible since
there could be more than a single frame.

To support this model, add a new callback to notify
drivers when frames are going to be released.

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

1 files changed, 17 insertions, 0 deletions

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index ee6449eff7dc..778572d38bd3 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -1973,6 +1973,18 @@ enum ieee80211_frame_release_type {
  *      service period ends, the driver must set %IEEE80211_TX_STATUS_EOSP
  *      on the last frame in the SP.
  *      This callback must be atomic.
+ * @allow_buffered_frames: Prepare device to allow the given number of frames
+ *      to go out to the given station. The frames will be sent by mac80211
+ *      via the usual TX path after this call. The TX information for frames
+ *      released will also have the %IEEE80211_TX_CTL_POLL_RESPONSE flag set
+ *      and the last one will also have %IEEE80211_TX_STATUS_EOSP set. In case
+ *      frames from multiple TIDs are released and the driver might reorder
+ *      them between the TIDs, it must set the %IEEE80211_TX_STATUS_EOSP flag
+ *      on the last frame and clear it on all others and also handle the EOSP
+ *      bit in the QoS header correctly.
+ *      The @tids parameter is a bitmap and tells the driver which TIDs the
+ *      frames will be on; it will at most have two bits set.
+ *      This callback must be atomic.
  */
 struct ieee80211_ops {
         void (*tx)(struct ieee80211_hw *hw, struct sk_buff *skb);
@@ -2088,6 +2100,11 @@ struct ieee80211_ops {
         void (*rssi_callback)(struct ieee80211_hw *hw,
                               enum ieee80211_rssi_event rssi_event);
 
+        void (*allow_buffered_frames)(struct ieee80211_hw *hw,
+                                      struct ieee80211_sta *sta,
+                                      u16 tids, int num_frames,
+                                      enum ieee80211_frame_release_type reason,
+                                      bool more_data);
         void (*release_buffered_frames)(struct ieee80211_hw *hw,
                                         struct ieee80211_sta *sta,
                                         u16 tids, int num_frames,