ar9170: implement transmit aggregation

This patch roughly implements xmit aggregation for ar9170-like device.
Not all AP are compatible with the driver(and firmware) yet, so YMMV.

A more refined code will definitely need the final HT specification
to be available for the public, lots of firmware modification and
possibly a redesigned driver just for good measure.
Sadly, these conditions won't come true anytime soon...
Signed-off-by: Christian Lamparter <chunkeey@web.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/ath/ar9170/ar9170.h

@@ -109,11 +109,52 @@ struct ar9170_rxstream_mpdu_merge {
 	bool has_plcp;
 };
 
+#define AR9170_NUM_MAX_BA_RETRY	5
+#define AR9170_NUM_TID	16
+#define WME_BA_BMP_SIZE         64
+#define AR9170_NUM_MAX_AGG_LEN	(2 * WME_BA_BMP_SIZE)
+
+#define WME_AC_BE   2
+#define WME_AC_BK   3
+#define WME_AC_VI   1
+#define WME_AC_VO   0
+
+#define TID_TO_WME_AC(_tid)				\
+	((((_tid) == 0) || ((_tid) == 3)) ? WME_AC_BE :	\
+	 (((_tid) == 1) || ((_tid) == 2)) ? WME_AC_BK :	\
+	 (((_tid) == 4) || ((_tid) == 5)) ? WME_AC_VI :	\
+	 WME_AC_VO)
+
+#define BAW_WITHIN(_start, _bawsz, _seqno) \
+	((((_seqno) - (_start)) & 0xfff) < (_bawsz))
+
+enum ar9170_tid_state {
+	AR9170_TID_STATE_INVALID,
+	AR9170_TID_STATE_SHUTDOWN,
+	AR9170_TID_STATE_PROGRESS,
+	AR9170_TID_STATE_COMPLETE,
+};
+
+struct ar9170_sta_tid {
+	struct list_head list;
+	struct sk_buff_head queue;
+	u8 addr[ETH_ALEN];
+	u16 ssn;
+	u16 tid;
+	enum ar9170_tid_state state;
+	bool active;
+	u8 retry;
+};
+
 #define AR9170_QUEUE_TIMEOUT		64
 #define AR9170_TX_TIMEOUT		8
+#define AR9170_BA_TIMEOUT		4
 #define AR9170_JANITOR_DELAY		128
 #define AR9170_TX_INVALID_RATE		0xffffffff
 
+#define AR9170_NUM_TX_STATUS		128
+#define AR9170_NUM_TX_AGG_MAX		30
+
 struct ar9170 {
 	struct ieee80211_hw *hw;
 	struct mutex mutex;
@@ -187,14 +228,25 @@ struct ar9170 {
 	struct sk_buff_head tx_pending[__AR9170_NUM_TXQ];
 	struct sk_buff_head tx_status[__AR9170_NUM_TXQ];
 	struct delayed_work tx_janitor;
+	/* tx ampdu */
+	struct sk_buff_head tx_status_ampdu;
+	spinlock_t tx_ampdu_list_lock;
+	struct list_head tx_ampdu_list;
+	unsigned int tx_ampdu_pending;
 
 	/* rxstream mpdu merge */
 	struct ar9170_rxstream_mpdu_merge rx_mpdu;
 	struct sk_buff *rx_failover;
 	int rx_failover_missing;
+
+	/* (cached) HW A-MPDU settings */
+	u8 global_ampdu_density;
+	u8 global_ampdu_factor;
 };
 
 struct ar9170_sta_info {
+	struct ar9170_sta_tid agg[AR9170_NUM_TID];
+	unsigned int ampdu_max_len;
 };
 
 #define AR9170_TX_FLAG_WAIT_FOR_ACK	BIT(0)