[PATCH] rt2x00: Add get_tx_data_len callback function

The TX datalen must always be converted to a value rt73 and rt2500usb
understand. Both require to use a different size then skb->len.
First off this is required because the descriptor must be added,
but the second is because the value must be a multiple of either 2 or 4,
and it should not be a multiple of the USB packetmax

Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 16 insertions, 0 deletions

diff --git a/drivers/net/wireless/rt2x00/rt73usb.c b/drivers/net/wireless/rt2x00/rt73usb.c
index 919cca593bc1..4a78ca79c94a 100644
--- a/drivers/net/wireless/rt2x00/rt73usb.c
+++ b/drivers/net/wireless/rt2x00/rt73usb.c
@@ -1286,6 +1286,21 @@ static void rt73usb_write_tx_desc(struct rt2x00_dev *rt2x00dev,
         rt2x00_desc_write(txd, 0, word);
 }
 
+static int rt73usb_get_tx_data_len(struct rt2x00_dev *rt2x00dev,
+                                   int maxpacket, struct sk_buff *skb)
+{
+        int length;
+
+        /*
+         * The length _must_ be a multiple of 4,
+         * but it must _not_ be a multiple of the USB packet size.
+         */
+        length = roundup(skb->len, 4);
+        length += (4 * !(length % maxpacket));
+
+        return length;
+}
+
 /*
  * TX data initialization
  */
@@ -2012,6 +2027,7 @@ static const struct rt2x00lib_ops rt73usb_rt2x00_ops = {
         .link_tuner             = rt73usb_link_tuner,
         .write_tx_desc          = rt73usb_write_tx_desc,
         .write_tx_data          = rt2x00usb_write_tx_data,
+        .get_tx_data_len        = rt73usb_get_tx_data_len,
         .kick_tx_queue          = rt73usb_kick_tx_queue,
         .fill_rxdone            = rt73usb_fill_rxdone,
         .config_mac_addr        = rt73usb_config_mac_addr,