Re: Fixing rt2500pci

[Ivo van Doorn <ivdoorn@gmail.com>]

On Wednesday 30 July 2008, Peter Chubb wrote:
> 
> 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 are two problems with that patch.  Setting the Tx
> Length has been removed inadvertently, and one of the conditions for
> when to set ifs to IFS_SIFS has also been removed.
> 
> This patch fixes those things, and with it my card works again.
> 
> Signed-off-by: Peter Chubb <peterc@gelato.unsw.edu.au>
> 
> diff --git a/drivers/net/wireless/rt2x00/rt2500pci.c b/drivers/net/wireless/rt2x00/rt2500pci.c
> index 1724ce9..4ba2165 100644
> --- a/drivers/net/wireless/rt2x00/rt2500pci.c
> +++ b/drivers/net/wireless/rt2x00/rt2500pci.c
> @@ -1198,6 +1198,7 @@ static void rt2500pci_write_tx_desc(struct rt2x00_dev *rt2x00dev,
>  	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, skbdesc->data_len);
>  	rt2x00_set_field32(&word, TXD_W0_CIPHER_ALG, CIPHER_NONE);
>  	rt2x00_desc_write(txd, 0, word);
>  }

How could that have disappeared? good catch.
The above change is:

Acked-by: Ivo van Doorn <IvDoorn@gmail.com>

But:

> diff --git a/drivers/net/wireless/rt2x00/rt2x00dev.c b/drivers/net/wireless/rt2x00/rt2x00dev.c
> index e1368f7..a11d6ff 100644
> --- a/drivers/net/wireless/rt2x00/rt2x00dev.c
> +++ b/drivers/net/wireless/rt2x00/rt2x00dev.c
> @@ -691,7 +691,8 @@ void rt2x00lib_write_tx_desc(struct rt2x00_dev *rt2x00dev,
>  	 * Set ifs to IFS_SIFS when the this is not the first fragment,
>  	 * or this fragment came after RTS/CTS.
>  	 */
> -	if (test_bit(ENTRY_TXD_RTS_FRAME, &txdesc.flags)) {
> +	if ((seq_ctrl & IEEE80211_SCTL_FRAG)  ||
> +		test_bit(ENTRY_TXD_RTS_FRAME, &txdesc.flags)) {
>  		txdesc.ifs = IFS_SIFS;
>  	} else if (control->flags & IEEE80211_TXCTL_FIRST_FRAGMENT) {
>  		__set_bit(ENTRY_TXD_FIRST_FRAGMENT, &txdesc.flags);

The above does not correspond with legacy driver, so I am hesitant in accepting this change.
Unless you are _absolutely_ sure this change does fix the issue, and the databate count
initialization is not sufficient on its own. If that is not the case, please resend the patch with the
rt2x00dev.c change ommitted and my ack added. (Please add John Linville to the CC list as well,
so it can be merged faster :) )

Ivo