ACPI / nouveau: fix probing regression related to _DSM
authorJiang Liu <jiang.liu@linux.intel.com>
Thu, 20 Feb 2014 09:23:16 +0000 (17:23 +0800)
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>
Thu, 20 Feb 2014 20:19:47 +0000 (21:19 +0100)
commite284175a96e5af087ea7806b3e38282b524ff5b9
treef5c085ac2ac29ecd34543394a4991d16895994d6
parent6d0abeca3242a88cab8232e4acd7e2bf088f3bc2
ACPI / nouveau: fix probing regression related to _DSM

Fix regression caused by commit b072e53, which breaks loading nouveau
driver on optimus laptops.

On some platforms, ACPI _DSM method (nouveau_op_dsm_muid, function 0)
has special requirements on the fourth parameter, which is different
from ACPI specifications. So revert to the private implementation
to check availability of _DSM functions instead of using common
acpi_check_dsm() interface.

Fixes: b072e53b0a27 (ACPI / nouveau: replace open-coded _DSM code with helper functions)
Reported-and-tested-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
[rjw: Subject]
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
drivers/gpu/drm/nouveau/nouveau_acpi.c