Re: [RFT PATCH] libata: implement ATA_FLAG_SETXFER_POLLING and use it in pata_via

[Jeff Garzik <jeff@garzik.org>]

Tejun Heo wrote:
> This patch implements ATA_FLAG_SETXFER_POLLING and use in pata_via.
> If this flag is set, transfer mode setting performed by polling not by
> interrupt.  This should help those controllers which raise interrupt
> before the command is actually complete on SETXFER.
> 
> Rationale for this approach.
> 
> * uses existing facility and relatively simple
> * no busy sleep in the interrupt handler
> * updating drivers is easy
> 
> Signed-off-by: Tejun Heo <htejun@gmail.com>
> ---
> 
> Matthieu Castet, can you please test this patch?  It's against
> libata-dev#upstream, but -mm might work too.  If you want a patch
> against -mm, just let me know.
> 
> Jeff, Alan, what do you think about this approach?

If it works, I have no complaints...



> diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
> index 753b015..c71d896 100644
> --- a/drivers/ata/libata-core.c
> +++ b/drivers/ata/libata-core.c
> @@ -4082,7 +4082,8 @@ int ata_hsm_move(struct ata_port *ap, st
>  
>  fsm_start:
>  	DPRINTK("ata%u: protocol %d task_state %d (dev_stat 0x%X)\n",
> -		ap->id, qc->tf.protocol, ap->hsm_task_state, status);
> +		ap->id, qc->tf.protocol, ap->hsm_task_state, status,
> +		qc->tf.flags & ATA_TFLAG_POLLING);

You need to update the format string too...

	Jeff