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* Libata Pass Through PIO Multi Support
@ 2007-03-07 21:57 Fajun Chen
  2007-03-07 22:33 ` Jeff Garzik
  0 siblings, 1 reply; 3+ messages in thread
From: Fajun Chen @ 2007-03-07 21:57 UTC (permalink / raw)
  To: linux-ide@vger.kernel.org; +Cc: Tejun Heo, Jeff Garzik

Hi Folks,

In ata_scsi_pass_thru() function in libata-scsi.c, the following code
is in place:
        if (scsicmd[1] & 0xe0)
                /* PIO multi not supported yet */
                goto invalid_fld;
Could someone explain why the PIO multi is not supported in libata pass through?

As an experiments, I commented out above code and added code to
support Set Multiple Mode. It seems PIO Multi works. But again, there
may be some caveates which I am not aware of.

I use 2.6.18-rc2 and libata 2.00. Above code exists in latest revision
like 2.6.19.2 as well.

Thanks,
Fajun

^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: Libata Pass Through PIO Multi Support
  2007-03-07 21:57 Libata Pass Through PIO Multi Support Fajun Chen
@ 2007-03-07 22:33 ` Jeff Garzik
  2007-03-07 23:00   ` Fajun Chen
  0 siblings, 1 reply; 3+ messages in thread
From: Jeff Garzik @ 2007-03-07 22:33 UTC (permalink / raw)
  To: Fajun Chen; +Cc: linux-ide@vger.kernel.org, Tejun Heo

Fajun Chen wrote:
> Hi Folks,
> 
> In ata_scsi_pass_thru() function in libata-scsi.c, the following code
> is in place:
>        if (scsicmd[1] & 0xe0)
>                /* PIO multi not supported yet */
>                goto invalid_fld;
> Could someone explain why the PIO multi is not supported in libata pass 
> through?

That's just code left over from before we merged Albert Lee's patches 
adding PIO-multi support.  That check should probably just be removed.

	Jeff




^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: Libata Pass Through PIO Multi Support
  2007-03-07 22:33 ` Jeff Garzik
@ 2007-03-07 23:00   ` Fajun Chen
  0 siblings, 0 replies; 3+ messages in thread
From: Fajun Chen @ 2007-03-07 23:00 UTC (permalink / raw)
  To: Jeff Garzik; +Cc: linux-ide@vger.kernel.org, Tejun Heo

On 3/7/07, Jeff Garzik <jeff@garzik.org> wrote:
> Fajun Chen wrote:
> > Hi Folks,
> >
> > In ata_scsi_pass_thru() function in libata-scsi.c, the following code
> > is in place:
> >        if (scsicmd[1] & 0xe0)
> >                /* PIO multi not supported yet */
> >                goto invalid_fld;
> > Could someone explain why the PIO multi is not supported in libata pass
> > through?
>
> That's just code left over from before we merged Albert Lee's patches
> adding PIO-multi support.  That check should probably just be removed.
>

Could you please provide a pointer to Albert Lee's PIO multi patch?
I'm not sure if 2.6.18-rc2 with libata 2.00 has already got the patch.

Thanks,
Fajun

^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2007-03-07 23:00 UTC | newest]

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2007-03-07 21:57 Libata Pass Through PIO Multi Support Fajun Chen
2007-03-07 22:33 ` Jeff Garzik
2007-03-07 23:00   ` Fajun Chen

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