In kernel version 2.6.26-rc9 my wireless LAN card worked; but in the
released 2.6.26, my RaLink rt2500 card wouldn't associate.

Git-bisect led me to this patch:

	61486e0f68d1f8966c09b734566a187d42d65c54
	rt2x00: Remove ieee80211_tx_control argument from write_tx_desc()

I believe that there is a problem with that patch --- it
(inadvertantly) removes an extra line of code, that used to set the
DATABYTE_COUNT field.
 
This patch reinstates that line, and with it my card works again.

The original version I sent still used the skbdesc->data_len which has
been removed; this version of the patch applies on top of 2.6.27-rc1.
 
Signed-off-by: Peter Chubb <redacted>
Acked-by: Ivo van Doorn <redacted>


Index: linux-2.6-git/drivers/net/wireless/rt2x00/rt2500pci.c
===================================================================

--- linux-2.6-git.orig/drivers/net/wireless/rt2x00/rt2500pci.c	2008-07-31 10:58:43.000000000 +1000
+++ linux-2.6-git/drivers/net/wireless/rt2x00/rt2500pci.c	2008-07-31 11:40:44.000000000 +1000

@@ -1213,20 +1213,21 @@ static void rt2500pci_write_tx_desc(stru
 	rt2x00_set_field32(&word, TXD_W0_ACK,
 			   test_bit(ENTRY_TXD_ACK, &txdesc->flags));
 	rt2x00_set_field32(&word, TXD_W0_TIMESTAMP,
 			   test_bit(ENTRY_TXD_REQ_TIMESTAMP, &txdesc->flags));
 	rt2x00_set_field32(&word, TXD_W0_OFDM,
 			   test_bit(ENTRY_TXD_OFDM_RATE, &txdesc->flags));
 	rt2x00_set_field32(&word, TXD_W0_CIPHER_OWNER, 1);
 	rt2x00_set_field32(&word, TXD_W0_IFS, txdesc->ifs);
 	rt2x00_set_field32(&word, TXD_W0_RETRY_MODE,
 			   test_bit(ENTRY_TXD_RETRY_MODE, &txdesc->flags));
+	rt2x00_set_field32(&word, TXD_W0_DATABYTE_COUNT, skb->len);
 	rt2x00_set_field32(&word, TXD_W0_CIPHER_ALG, CIPHER_NONE);
 	rt2x00_desc_write(txd, 0, word);
 }
 
 /*
  * TX data initialization
  */
 static void rt2500pci_write_beacon(struct queue_entry *entry)
 {
 	struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev;

--

Dr Peter Chubb  http://www.gelato.unsw.edu.au  peterc AT gelato.unsw.edu.au
http://www.ertos.nicta.com.au           ERTOS within National ICT Australia