Re: [PATCH] ACPI driver support for pata

From: Robert Hancock
Date: Thu Feb 22 2007 - 19:16:37 EST


Alan wrote:
On Thu, 22 Feb 2007 12:11:32 -0500
Jeff Garzik <jeff@xxxxxxxxxx> wrote:

Alan wrote:
ACPI is the only way to do cable handling on the Nvidia PATA chipset. The
You failed to quote the salient part of the message. Disliking a separate pata_acpi driver in no way invalidates your statement (quoted above).

If you drive a device by the ACPI interface you don't get to fiddle with
it directly or you end up in a murky world of undefined and ungood
behaviour. Testing and vendor information both say pata_acpi is the right
way to drive Nvidia PATA ports.

Couldn't be do this generically inside libata core somehow, i.e. try to use ACPI to set the proper mode and fall back to the driver-specific mode setting code if that didn't work? I think if we could do that it would solve a number of problems (i.e. we could prevent it from doing this on SATA controllers which appear to be IDE based on the PCI ID, like the NVIDIA SATA controllers, since the _GTM and _STM methods seem to have undefined behavior on SATA). This would also eliminate the need for mkinitrd, people, etc. to know that they're supposed to be loading this other pata_acpi driver instead, since any PATA driver could take advantage of this feature.

--
Robert Hancock Saskatoon, SK, Canada
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Home Page: http://www.roberthancock.com/

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