rt2x00: Reverse calling order of bus write_tx_desc and driver write_tx_desc.

For rt2800 reverse the calling order of rt2x00pci_write_data and
rt2800pci_write_data. Currently rt2800pci_write_data calls rt2x00pci_write_data
as there can be only 1 driver callback function specified by the driver.
Reverse this calling order by introducing a new driver callback function,
called write_tx_datadesc, which is called from the bus-specific write_tx_data
functions.
Preparation for futher cleanups in the skb data handling of rt2x00.

Signed-off-by: Gertjan van Wingerde <gwingerde@gmail.com>
Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>

drivers/net/wireless/rt2x00/rt2800pci.c

@@ -613,18 +613,10 @@ static int rt2800pci_set_device_state(struct rt2x00_dev *rt2x00dev,
 /*
  * TX descriptor initialization
  */
-static int rt2800pci_write_tx_data(struct queue_entry* entry,
-				   struct txentry_desc *txdesc)
+static void rt2800pci_write_tx_datadesc(struct queue_entry* entry,
+					 struct txentry_desc *txdesc)
 {
-	int ret;
-
-	ret = rt2x00pci_write_tx_data(entry, txdesc);
-	if (ret)
-		return ret;
-
 	rt2800_write_txwi(entry->skb, txdesc);
-
-	return 0;
 }
 
 
@@ -1079,7 +1071,8 @@ static const struct rt2x00lib_ops rt2800pci_rt2x00_ops = {
 	.reset_tuner		= rt2800_reset_tuner,
 	.link_tuner		= rt2800_link_tuner,
 	.write_tx_desc		= rt2800pci_write_tx_desc,
-	.write_tx_data		= rt2800pci_write_tx_data,
+	.write_tx_data		= rt2x00pci_write_tx_data,
+	.write_tx_datadesc	= rt2800pci_write_tx_datadesc,
 	.write_beacon		= rt2800pci_write_beacon,
 	.kick_tx_queue		= rt2800pci_kick_tx_queue,
 	.kill_tx_queue		= rt2800pci_kill_tx_queue,

drivers/net/wireless/rt2x00/rt2x00.h

@@ -552,6 +552,8 @@ struct rt2x00lib_ops {
 			       struct txentry_desc *txdesc);
 	int (*write_tx_data) (struct queue_entry *entry,
 			      struct txentry_desc *txdesc);
+	void (*write_tx_datadesc) (struct queue_entry *entry,
+				   struct txentry_desc *txdesc);
 	void (*write_beacon) (struct queue_entry *entry,
 			      struct txentry_desc *txdesc);
 	int (*get_tx_data_len) (struct queue_entry *entry);

drivers/net/wireless/rt2x00/rt2x00pci.c

@@ -81,6 +81,12 @@ int rt2x00pci_write_tx_data(struct queue_entry *entry,
 		return -EINVAL;
 	}
 
+	/*
+	 * Call the driver's write_tx_datadesc function, if it exists.
+	 */
+	if (rt2x00dev->ops->lib->write_tx_datadesc)
+		rt2x00dev->ops->lib->write_tx_datadesc(entry, txdesc);
+
 	return 0;
 }
 EXPORT_SYMBOL_GPL(rt2x00pci_write_tx_data);

drivers/net/wireless/rt2x00/rt2x00usb.c

@@ -248,6 +248,12 @@ int rt2x00usb_write_tx_data(struct queue_entry *entry,
 	 */
 	skb_pull(entry->skb, entry->queue->desc_size);
 
+	/*
+	 * Call the driver's write_tx_datadesc function, if it exists.
+	 */
+	if (rt2x00dev->ops->lib->write_tx_datadesc)
+		rt2x00dev->ops->lib->write_tx_datadesc(entry, txdesc);
+
 	return 0;
 }
 EXPORT_SYMBOL_GPL(rt2x00usb_write_tx_data);