ata_piix: make DVD Drive recognisable on systems with Intel Sandybridge chipsets(v2)
authorMing Lei <ming.lei@canonical.com>
Fri, 7 Oct 2011 03:50:22 +0000 (11:50 +0800)
committerJeff Garzik <jgarzik@redhat.com>
Sat, 8 Oct 2011 03:46:37 +0000 (23:46 -0400)
commit5e5a4f5d5a08c9c504fe956391ac3dae2c66556d
tree7e5aad3c063b2972d3890afbf3b847e39a4b57de
parent21dba24481f70696308bd4361a7b2460c8a41965
ata_piix: make DVD Drive recognisable on systems with Intel Sandybridge chipsets(v2)

This quirk patch fixes one kind of bug inside some Intel Sandybridge
chipsets, see reports from

       https://bugzilla.kernel.org/show_bug.cgi?id=40592.

Many guys also have reported the problem before:

https://bugs.launchpad.net/bugs/737388
https://bugs.launchpad.net/bugs/794642
https://bugs.launchpad.net/bugs/782389
......

With help from Tejun, the problem is found to be caused by 32bit PIO
mode, so introduce the quirk patch to disable 32bit PIO on SATA piix
for some Sandybridge CPT chipsets.

Seth also tested the patch on all five affected chipsets
(pci device ID: 0x1c00, 0x1c01, 0x1d00, 0x1e00, 0x1e01), and found
the patch does fix the problem.

Tested-by: Heasley, Seth <seth.heasley@intel.com>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Acked-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Cc: stable@kernel.org
drivers/ata/ata_piix.c