libertas: Move actual transmission to main thread

The locking issues with TX, especially TX from multiple netdevs, get
_so_ much easier if you do it like this.

Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/libertas/main.c b/drivers/net/wireless/libertas/main.c
index 42b64b5..f16c93b 100644
--- a/drivers/net/wireless/libertas/main.c
+++ b/drivers/net/wireless/libertas/main.c
@@ -739,6 +739,8 @@
 			shouldsleep = 0;	/* Interrupt pending. Deal with it now */
 		else if (priv->dnld_sent)
 			shouldsleep = 1;	/* Something is en route to the device already */
+		else if (priv->tx_pending_len > 0)
+			shouldsleep = 0;	/* We've a packet to send */
 		else if (priv->cur_cmd)
 			shouldsleep = 1;	/* Can't send a command; one already running */
 		else if (!list_empty(&priv->cmdpendingq))
@@ -852,6 +854,28 @@
 		 */
 		if (!list_empty(&priv->cmdpendingq))
 			wake_up_all(&priv->cmd_pending);
+
+		spin_lock_irq(&priv->driver_lock);
+		if (!priv->dnld_sent && priv->tx_pending_len > 0) {
+			int ret = priv->hw_host_to_card(priv, MVMS_DAT,
+							priv->tx_pending_buf,
+							priv->tx_pending_len);
+			if (ret) {
+				lbs_deb_tx("host_to_card failed %d\n", ret);
+				priv->dnld_sent = DNLD_RES_RECEIVED;
+			}
+			priv->tx_pending_len = 0;
+			if (!priv->currenttxskb) {
+				/* We can wake the queues immediately if we aren't
+				   waiting for TX feedback */
+				if (priv->connect_status == LBS_CONNECTED)
+					netif_wake_queue(priv->dev);
+				if (priv->mesh_dev &&
+				    priv->mesh_connect_status == LBS_CONNECTED)
+					netif_wake_queue(priv->mesh_dev);
+			}
+		}
+		spin_unlock_irq(&priv->driver_lock);
 	}
 
 	del_timer(&priv->command_timer);