ath9k_htc: Add support for TX completion

Now that the infrastructure is in place, process WMI
TX status events and complete packets.

Signed-off-by: Sujith Manoharan <Sujith.Manoharan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/ath/ath9k/wmi.c b/drivers/net/wireless/ath/ath9k/wmi.c
index e66f6c3..3f5a4d1 100644
--- a/drivers/net/wireless/ath/ath9k/wmi.c
+++ b/drivers/net/wireless/ath/ath9k/wmi.c
@@ -163,6 +163,16 @@
 			wmi->drv_priv->debug.txrate = be32_to_cpu(txrate);
 #endif
 			break;
+		case WMI_TXSTATUS_EVENTID:
+			spin_lock_bh(&priv->tx.tx_lock);
+			if (priv->tx.flags & ATH9K_HTC_OP_TX_DRAIN) {
+				spin_unlock_bh(&priv->tx.tx_lock);
+				break;
+			}
+			spin_unlock_bh(&priv->tx.tx_lock);
+
+			ath9k_htc_txstatus(priv, wmi_event);
+			break;
 		default:
 			break;
 		}