iwlwifi: mvm: implement AP/GO uAPSD support

Newer firmware will support uAPSD clients in AP/GO mode, so complete
the driver support for it. The way it works is described in comments
in the code, but basically the driver just has to pass down all the
mac80211 requests and do accounting on agg/non-agg queues properly.

For older firmware, this doesn't change anything as it ignores the
fields used by the new firmware, and we only advertise uAPSD support
when the firmware does.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>

1 files changed, 40 insertions, 17 deletions

diff --git a/drivers/net/wireless/iwlwifi/mvm/sta.h b/drivers/net/wireless/iwlwifi/mvm/sta.h
index 4968d02..64f9a1b 100644
--- a/drivers/net/wireless/iwlwifi/mvm/sta.h
+++ b/drivers/net/wireless/iwlwifi/mvm/sta.h
@@ -195,24 +195,33 @@ struct iwl_mvm;
 /**
  * DOC: AP mode - PS
  *
- * When a station is asleep, the fw will set it as "asleep". All the
- * non-aggregation frames to that station will be dropped by the fw
- * (%TX_STATUS_FAIL_DEST_PS failure code).
+ * When a station is asleep, the fw will set it as "asleep". All frames on
+ * shared queues (i.e. non-aggregation queues) to that station will be dropped
+ * by the fw (%TX_STATUS_FAIL_DEST_PS failure code).
+ *
  * AMPDUs are in a separate queue that is stopped by the fw. We just need to
- * let mac80211 know how many frames we have in these queues so that it can
+ * let mac80211 know when there are frames in these queues so that it can
  * properly handle trigger frames.
- * When the a trigger frame is received, mac80211 tells the driver to send
- * frames from the AMPDU queues or AC queue depending on which queue are
- * delivery-enabled and what TID has frames to transmit (Note that mac80211 has
- * all the knowledege since all the non-agg frames are buffered / filtered, and
- * the driver tells mac80211 about agg frames). The driver needs to tell the fw
- * to let frames out even if the station is asleep. This is done by
- * %iwl_mvm_sta_modify_sleep_tx_count.
- * When we receive a frame from that station with PM bit unset, the
- * driver needs to let the fw know that this station isn't alseep any more.
- * This is done by %iwl_mvm_sta_modify_ps_wake.
- *
- * TODO - EOSP handling
+ *
+ * When a trigger frame is received, mac80211 tells the driver to send frames
+ * from the AMPDU queues or sends frames to non-aggregation queues itself,
+ * depending on which ACs are delivery-enabled and what TID has frames to
+ * transmit. Note that mac80211 has all the knowledege since all the non-agg
+ * frames are buffered / filtered, and the driver tells mac80211 about agg
+ * frames). The driver needs to tell the fw to let frames out even if the
+ * station is asleep. This is done by %iwl_mvm_sta_modify_sleep_tx_count.
+ *
+ * When we receive a frame from that station with PM bit unset, the driver
+ * needs to let the fw know that this station isn't asleep any more. This is
+ * done by %iwl_mvm_sta_modify_ps_wake in response to mac80211 signalling the
+ * station's wakeup.
+ *
+ * For a GO, the Service Period might be cut short due to an absence period
+ * of the GO. In this (and all other cases) the firmware notifies us with the
+ * EOSP_NOTIFICATION, and we notify mac80211 of that. Further frames that we
+ * already sent to the device will be rejected again.
+ *
+ * See also "AP support for powersaving clients" in mac80211.h.
  */
 
 /**
@@ -261,6 +270,12 @@ struct iwl_mvm_tid_data {
 	u16 ssn;
 };
 
+static inline u16 iwl_mvm_tid_queued(struct iwl_mvm_tid_data *tid_data)
+{
+	return ieee80211_sn_sub(IEEE80211_SEQ_TO_SN(tid_data->seq_number),
+				tid_data->next_reclaimed);
+}
+
 /**
  * struct iwl_mvm_sta - representation of a station in the driver
  * @sta_id: the index of the station in the fw (will be replaced by id_n_color)
@@ -270,6 +285,8 @@ struct iwl_mvm_tid_data {
  *	tid.
  * @max_agg_bufsize: the maximal size of the AGG buffer for this station
  * @bt_reduced_txpower: is reduced tx power enabled for this station
+ * @next_status_eosp: the next reclaimed packet is a PS-Poll response and
+ *	we need to signal the EOSP
  * @lock: lock to protect the whole struct. Since %tid_data is access from Tx
  * and from Tx response flow, it needs a spinlock.
  * @tid_data: per tid data. Look at %iwl_mvm_tid_data.
@@ -288,6 +305,7 @@ struct iwl_mvm_sta {
 	u16 tid_disable_agg;
 	u8 max_agg_bufsize;
 	bool bt_reduced_txpower;
+	bool next_status_eosp;
 	spinlock_t lock;
 	struct iwl_mvm_tid_data tid_data[IWL_MAX_TID_COUNT];
 	struct iwl_lq_sta lq_sta;
@@ -345,6 +363,10 @@ void iwl_mvm_update_tkip_key(struct iwl_mvm *mvm,
 			     struct ieee80211_sta *sta, u32 iv32,
 			     u16 *phase1key);
 
+int iwl_mvm_rx_eosp_notif(struct iwl_mvm *mvm,
+			  struct iwl_rx_cmd_buffer *rxb,
+			  struct iwl_device_cmd *cmd);
+
 /* AMPDU */
 int iwl_mvm_sta_rx_agg(struct iwl_mvm *mvm, struct ieee80211_sta *sta,
 		       int tid, u16 ssn, bool start);
@@ -375,7 +397,8 @@ void iwl_mvm_sta_modify_ps_wake(struct iwl_mvm *mvm,
 void iwl_mvm_sta_modify_sleep_tx_count(struct iwl_mvm *mvm,
 				       struct ieee80211_sta *sta,
 				       enum ieee80211_frame_release_type reason,
-				       u16 cnt);
+				       u16 cnt, u16 tids, bool more_data,
+				       bool agg);
 int iwl_mvm_drain_sta(struct iwl_mvm *mvm, struct iwl_mvm_sta *mvmsta,
 		      bool drain);