rt2x00: Pad beacon to multiple of 32 bits.

Pad beacon to a multiple of 32 bits in preparation for the change
from memcpy_toio() to __iowrite32_copy() in register_multiwrite().

Signed-off-by: Wolfgang Kufner <wolfgang.kufner@gmail.com>
Acked-by: Helmut Schaa <helmut.schaa@googlemail.com>
Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/rt2x00/rt73usb.c b/drivers/net/wireless/rt2x00/rt73usb.c
index 0b3959b..0b4e859 100644
--- a/drivers/net/wireless/rt2x00/rt73usb.c
+++ b/drivers/net/wireless/rt2x00/rt73usb.c
@@ -1546,6 +1546,7 @@
 {
 	struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev;
 	unsigned int beacon_base;
+	unsigned int padding_len;
 	u32 reg;
 
 	/*
@@ -1573,11 +1574,13 @@
 	rt2x00debug_dump_frame(rt2x00dev, DUMP_FRAME_BEACON, entry->skb);
 
 	/*
-	 * Write entire beacon with descriptor to register.
+	 * Write entire beacon with descriptor and padding to register.
 	 */
+	padding_len = roundup(entry->skb->len, 4) - entry->skb->len;
+	skb_pad(entry->skb, padding_len);
 	beacon_base = HW_BEACON_OFFSET(entry->entry_idx);
-	rt2x00usb_register_multiwrite(rt2x00dev, beacon_base,
-				      entry->skb->data, entry->skb->len);
+	rt2x00usb_register_multiwrite(rt2x00dev, beacon_base, entry->skb->data,
+				      entry->skb->len + padding_len);
 
 	/*
 	 * Enable beaconing again.