mac80211: implement uAPSD

Add uAPSD support to mac80211. This is probably not
possible with all devices, so advertising it with
the cfg80211 flag will be left up to drivers that
want it.

Due to my previous patches it is now a fairly
straight-forward extension. Drivers need to have
accurate TX status reporting for the EOSP frame.
For drivers that buffer themselves, the provided
APIs allow releasing the right number of frames,
but then drivers need to set EOSP and more-data
themselves. This is documented in more detail in
the new code itself.

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

1 files changed, 17 insertions, 7 deletions

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index dc2ea46eb5d6..dd07964ef154 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -339,9 +339,9 @@ struct ieee80211_bss_conf {
  *      used to indicate that a frame was already retried due to PS
  * @IEEE80211_TX_INTFL_DONT_ENCRYPT: completely internal to mac80211,
  *      used to indicate frame should not be encrypted
- * @IEEE80211_TX_CTL_PSPOLL_RESPONSE: (internal?)
- *      This frame is a response to a PS-poll frame and should be sent
- *      although the station is in powersave mode.
+ * @IEEE80211_TX_CTL_POLL_RESPONSE: This frame is a response to a poll
+ *      frame (PS-Poll or uAPSD) and should be sent although the station
+ *      is in powersave mode.
  * @IEEE80211_TX_CTL_MORE_FRAMES: More frames will be passed to the
  *      transmit function after the current frame, this can be used
  *      by drivers to kick the DMA queue only if unset or when the
@@ -367,6 +367,10 @@ struct ieee80211_bss_conf {
  * @IEEE80211_TX_CTL_NO_CCK_RATE: This frame will be sent at non CCK rate.
  *      This flag is actually used for management frame especially for P2P
  *      frames not being sent at CCK rate in 2GHz band.
+ * @IEEE80211_TX_STATUS_EOSP: This packet marks the end of service period,
+ *      when its status is reported the service period ends. For frames in
+ *      an SP that mac80211 transmits, it is already set; for driver frames
+ *      the driver may set this flag.
  *
  * Note: If you have to add new flags to the enumeration, then don't
  *       forget to update %IEEE80211_TX_TEMPORARY_FLAGS when necessary.
@@ -388,7 +392,7 @@ enum mac80211_tx_control_flags {
         IEEE80211_TX_INTFL_NEED_TXPROCESSING    = BIT(14),
         IEEE80211_TX_INTFL_RETRIED              = BIT(15),
         IEEE80211_TX_INTFL_DONT_ENCRYPT         = BIT(16),
-        IEEE80211_TX_CTL_PSPOLL_RESPONSE        = BIT(17),
+        IEEE80211_TX_CTL_POLL_RESPONSE          = BIT(17),
         IEEE80211_TX_CTL_MORE_FRAMES            = BIT(18),
         IEEE80211_TX_INTFL_RETRANSMISSION       = BIT(19),
         IEEE80211_TX_INTFL_HAS_RADIOTAP         = BIT(20),
@@ -398,6 +402,7 @@ enum mac80211_tx_control_flags {
         IEEE80211_TX_CTL_TX_OFFCHAN             = BIT(25),
         IEEE80211_TX_INTFL_TKIP_MIC_FAILURE     = BIT(26),
         IEEE80211_TX_CTL_NO_CCK_RATE            = BIT(27),
+        IEEE80211_TX_STATUS_EOSP                = BIT(28),
 };
 
 #define IEEE80211_TX_CTL_STBC_SHIFT             23
@@ -411,9 +416,9 @@ enum mac80211_tx_control_flags {
         IEEE80211_TX_CTL_SEND_AFTER_DTIM | IEEE80211_TX_CTL_AMPDU |           \
         IEEE80211_TX_STAT_TX_FILTERED | IEEE80211_TX_STAT_ACK |               \
         IEEE80211_TX_STAT_AMPDU | IEEE80211_TX_STAT_AMPDU_NO_BACK |           \
-        IEEE80211_TX_CTL_RATE_CTRL_PROBE | IEEE80211_TX_CTL_PSPOLL_RESPONSE | \
+        IEEE80211_TX_CTL_RATE_CTRL_PROBE | IEEE80211_TX_CTL_POLL_RESPONSE |   \
         IEEE80211_TX_CTL_MORE_FRAMES | IEEE80211_TX_CTL_LDPC |                \
-        IEEE80211_TX_CTL_STBC)
+        IEEE80211_TX_CTL_STBC | IEEE80211_TX_STATUS_EOSP)
 
 /**
  * enum mac80211_rate_control_flags - per-rate flags set by the
@@ -1624,9 +1629,12 @@ enum ieee80211_tx_sync_type {
 /**
  * enum ieee80211_frame_release_type - frame release reason
  * @IEEE80211_FRAME_RELEASE_PSPOLL: frame released for PS-Poll
+ * @IEEE80211_FRAME_RELEASE_UAPSD: frame(s) released due to
+ *      frame received on trigger-enabled AC
  */
 enum ieee80211_frame_release_type {
         IEEE80211_FRAME_RELEASE_PSPOLL,
+        IEEE80211_FRAME_RELEASE_UAPSD,
 };
 
 /**
@@ -1954,7 +1962,9 @@ enum ieee80211_frame_release_type {
  *      In the case this is used for uAPSD, the @num_frames parameter may be
  *      bigger than one, but the driver may send fewer frames (it must send
  *      at least one, however). In this case it is also responsible for
- *      setting the EOSP flag in the QoS header of the frames.
+ *      setting the EOSP flag in the QoS header of the frames. Also, when the
+ *      service period ends, the driver must set %IEEE80211_TX_STATUS_EOSP
+ *      on the last frame in the SP.
  *      This callback must be atomic.
  */
 struct ieee80211_ops {