ACPI video: Still use ACPI backlight control if _DOS doesn't exist
authorZhang Rui <rui.zhang@intel.com>
Wed, 20 Jun 2012 01:48:43 +0000 (09:48 +0800)
committerLen Brown <len.brown@intel.com>
Sat, 30 Jun 2012 04:43:42 +0000 (00:43 -0400)
commitb03738430c7537d5f87948e0b35d8aaf2688c6b4
tree70dd0d5aa1e40118bf60c5c6642bbc8715768722
parent76e10d158efb6d4516018846f60c2ab5501900bc
ACPI video: Still use ACPI backlight control if _DOS doesn't exist

This fixes a regression in 3.4-rc1 caused by commit
ea9f8856bd6d4ed45885b06a338f7362cd6c60e5
(ACPI video: Harden video bus adding.)

Some platforms don't have _DOS control method, but the ACPI
backlight still works.
We should not invoke _DOS for these platforms.

https://bugzilla.kernel.org/show_bug.cgi?id=43168

Cc: Igor Murzov <intergalactic.anonymous@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
drivers/acpi/video.c