tree f6c7dace53bbd30ad3b79160265b5e470c52f1f2
parent f57e91682d141ea50d8c6d42cdc251b6256a3755
author Tejun Heo <tj@kernel.org> 1215353703 +0900
committer Jeff Garzik <jgarzik@redhat.com> 1215783503 -0400

libata-acpi: filter out DIPM enable

Some BIOSen enable DIPM via _GTF which causes command timeouts under
certain configuration.  This didn't occur on 2.6.25 because 2.6.25
defaulted to SRST, so _GTF wasn't executed during boot probe, so ahci
host reset disabled DIPM and as _GTF wasn't executed after SRST, DIPM
wasn't enabled.  On 2.6.26, hardreset is used during probe and after
probe _GTF is executed enabling DIPM and thus the failures.

This patch could theoretically disable DIPM on machines which used to
have it enabled on 2.6.25 but AFAIK ahci is currently the only driver
which uses SATA ACPI hierarchy (_SDD) and as the host reset would have
always disabled DIPM, this shouldn't happen.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>