ATH9K_HTC_OP_TX_DRAIN
priv->tx.flags |= ATH9K_HTC_OP_TX_DRAIN;
priv->tx.flags &= ~ATH9K_HTC_OP_TX_DRAIN;
if (priv->tx.flags & ATH9K_HTC_OP_TX_DRAIN) {
if (priv->tx.flags & ATH9K_HTC_OP_TX_DRAIN) {