Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-next-2.6 into for-davem

1 files changed, 14 insertions, 12 deletions

diff --git a/drivers/net/wireless/rt2x00/rt2400pci.c b/drivers/net/wireless/rt2x00/rt2400pci.c
index 6126c0ab5880..4ba7b038928f 100644
--- a/drivers/net/wireless/rt2x00/rt2400pci.c
+++ b/drivers/net/wireless/rt2x00/rt2400pci.c
@@ -1007,15 +1007,15 @@ static void rt2400pci_write_tx_desc(struct rt2x00_dev *rt2x00dev,
 {
 	struct skb_frame_desc *skbdesc = get_skb_frame_desc(skb);
 	struct queue_entry_priv_pci *entry_priv = skbdesc->entry->priv_data;
-	__le32 *txd = skbdesc->desc;
+	__le32 *txd = entry_priv->desc;
 	u32 word;
 
 	/*
 	 * Start writing the descriptor words.
 	 */
-	rt2x00_desc_read(entry_priv->desc, 1, &word);
+	rt2x00_desc_read(txd, 1, &word);
 	rt2x00_set_field32(&word, TXD_W1_BUFFER_ADDRESS, skbdesc->skb_dma);
-	rt2x00_desc_write(entry_priv->desc, 1, word);
+	rt2x00_desc_write(txd, 1, word);
 
 	rt2x00_desc_read(txd, 2, &word);
 	rt2x00_set_field32(&word, TXD_W2_BUFFER_LENGTH, txdesc->length);
@@ -1040,6 +1040,11 @@ static void rt2400pci_write_tx_desc(struct rt2x00_dev *rt2x00dev,
 	rt2x00_set_field32(&word, TXD_W3_PLCP_LENGTH_HIGH_BUSY, 1);
 	rt2x00_desc_write(txd, 4, word);
 
+	/*
+	 * Writing TXD word 0 must the last to prevent a race condition with
+	 * the device, whereby the device may take hold of the TXD before we
+	 * finished updating it.
+	 */
 	rt2x00_desc_read(txd, 0, &word);
 	rt2x00_set_field32(&word, TXD_W0_OWNER_NIC, 1);
 	rt2x00_set_field32(&word, TXD_W0_VALID, 1);
@@ -1055,6 +1060,12 @@ static void rt2400pci_write_tx_desc(struct rt2x00_dev *rt2x00dev,
 	rt2x00_set_field32(&word, TXD_W0_RETRY_MODE,
 			   test_bit(ENTRY_TXD_RETRY_MODE, &txdesc->flags));
 	rt2x00_desc_write(txd, 0, word);
+
+	/*
+	 * Register descriptor details in skb frame descriptor.
+	 */
+	skbdesc->desc = txd;
+	skbdesc->desc_len = TXD_DESC_SIZE;
 }
 
 /*
@@ -1077,15 +1088,6 @@ static void rt2400pci_write_beacon(struct queue_entry *entry,
 	rt2x00_set_field32(&reg, CSR14_BEACON_GEN, 0);
 	rt2x00pci_register_write(rt2x00dev, CSR14, reg);
 
-	/*
-	 * Replace rt2x00lib allocated descriptor with the
-	 * pointer to the _real_ hardware descriptor.
-	 * After that, map the beacon to DMA and update the
-	 * descriptor.
-	 */
-	memcpy(entry_priv->desc, skbdesc->desc, skbdesc->desc_len);
-	skbdesc->desc = entry_priv->desc;
-
 	rt2x00queue_map_txskb(rt2x00dev, entry->skb);
 
 	rt2x00_desc_read(entry_priv->desc, 1, &word);