Re: EP93xx PIO IDE driver proposal

[Sergei Shtylyov <sshtylyov@ru.mvista.com>]

Hello.

João Ramos wrote:

>>>> Well, yes.  Though I hoped that you would at least give a try to fixing
>>>> IDE core to program PIO0 initially for all host drivers that implement
>>>> ->set_pio_mode method...

>>> Sorry, I didn't noticed your hint... Sure, I can give it a try ;-)
>>> Maybe with a little help, but I can try. You mean, when the host 
>>> driver is registered (ide_host_register, or ide_host_add that later 
>>> calls ide_host_register), maybe in the 'ide_init_port' method (sorry, 
>>> I need some guidance here...) check if the 'set_pio_mode' method is 
>>> implemented, and after initializing each port (d->init_hwif(hwif)) 
>>> default it to PIO Mode 0, calling set_pio_mode method.

>> ide_init_port() seems OK but I think that ide_port_init_devices()
>> [it is called after ide_init_port()] would be a bit safer and more
>> flexible (some host drivers may also require special ->init_dev
>> setup first) and the check for ->set_pio_mode method presence can
>> be done just before actually using the method, i.e.

>>     const struct ide_port_ops *port_ops = hwif->port_ops;

>>     if (port_ops && port_ops->set_pio_mode)
>>         port_ops->set_pio_mode(...)

> Ok, so the patch for this is attached in this e-mail.

> Please confirm and make your comments.

> Best regards,
> João Ramos

> ------------------------------------------------------------------------
> 
> Initially set PIO Mode 0 for all host drivers that use PIO transfer mode

    All drivers have to use the PIO mode (at least to transfer the taskfile 
-- and for some PIO only commands too).

> (and export a 'set_pio_mode' method)

    s/export/have/

> before the IDE core figures out
> the most suited PIO mode for the attached device.

> Signed-off-by: Joao Ramos <joao.ramos@inov.pt>
> Cc: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
> Cc: Sergei Shtylyov <sshtylyov@ru.montavista.com>
> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>

    Alan is hardly much interested in the IDE patches. :-)

> ---

> diff --git a/drivers/ide/ide-probe.c b/drivers/ide/ide-probe.c
> index 7f264ed..f92cac4 100644
> --- a/drivers/ide/ide-probe.c
> +++ b/drivers/ide/ide-probe.c
> @@ -1031,6 +1031,13 @@ static void ide_port_init_devices(ide_hwif_t *hwif)
>  
>  		if (port_ops && port_ops->init_dev)
>  			port_ops->init_dev(drive);
> +
> +		/*
> +		 * if driver uses PIO mode,

    This passage is pointless.

> default to PIO Mode 0 before we
> +		 * figure out the most suited mode for the attached device
> +		 */
> +		if (port_ops && port_ops->set_pio_mode)
> +			port_ops->set_pio_mode(drive, 0);
>  	}
>  }
>  

MBR, Sergei