ath9k: improve ath_tx_aggr_stop to avoid TID stuck in cleanup state

When tx agg is being stopped TID is flushed using ath_tx_flush_tid. It
is possible that ath_tx_flush_tid completelly flushes TID (if all
packets in this TID have already been retried). If this happened
ath_tx_aggr_stop would leave TID in cleanup state permanently.
Fix this by making ath_tx_flush_tid remove AGGR_ADDBA_COMPLETE and
AGGR_CLEANUP flags from TID status if TID is empty.
Signed-off-by: NNikolay Martynov <mar.kolya@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

drivers/net/wireless/ath/ath9k/xmit.c

@@ -179,6 +179,11 @@ static void ath_tx_flush_tid(struct ath_softc *sc, struct ath_atx_tid *tid)
 		spin_lock_bh(&txq->axq_lock);
 	}
 
+	if (tid->baw_head == tid->baw_tail) {
+		tid->state &= ~AGGR_ADDBA_COMPLETE;
+		tid->state &= ~AGGR_CLEANUP;
+	}
+
 	spin_unlock_bh(&txq->axq_lock);
 }
 
@@ -556,15 +561,9 @@ static void ath_tx_complete_aggr(struct ath_softc *sc, struct ath_txq *txq,
 		spin_unlock_bh(&txq->axq_lock);
 	}
 
-	if (tid->state & AGGR_CLEANUP) {
+	if (tid->state & AGGR_CLEANUP)
 		ath_tx_flush_tid(sc, tid);
 
-		if (tid->baw_head == tid->baw_tail) {
-			tid->state &= ~AGGR_ADDBA_COMPLETE;
-			tid->state &= ~AGGR_CLEANUP;
-		}
-	}
-
 	rcu_read_unlock();
 
 	if (needreset) {