From: Alex Hung <alex.hung@canonical.com>
Date: Fri, 27 May 2016 07:47:06 +0000 (+0800)
Subject: ACPI / video: skip evaluating _DOD when it does not exist
X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=e34fbbac669de0b7fb7803929d0477f35f6e2833;p=deliverable%2Flinux.git

ACPI / video: skip evaluating _DOD when it does not exist

Some system supports hybrid graphics and its discrete VGA
does not have any connectors and therefore has no _DOD method.

Signed-off-by: Alex Hung <alex.hung@canonical.com>
Reviewed-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---

diff --git a/drivers/acpi/acpi_video.c b/drivers/acpi/acpi_video.c
index c1d138e128cb..c5557d070954 100644
--- a/drivers/acpi/acpi_video.c
+++ b/drivers/acpi/acpi_video.c
@@ -1246,6 +1246,9 @@ static int acpi_video_device_enumerate(struct acpi_video_bus *video)
 	union acpi_object *dod = NULL;
 	union acpi_object *obj;
 
+	if (!video->cap._DOD)
+		return AE_NOT_EXIST;
+
 	status = acpi_evaluate_object(video->device->handle, "_DOD", NULL, &buffer);
 	if (!ACPI_SUCCESS(status)) {
 		ACPI_EXCEPTION((AE_INFO, status, "Evaluating _DOD"));