ACPI: video: Loosen strictness of video bus detection code

BugLink: http://bugs.launchpad.net/bugs/333386

Currently a video bus device must (beside other criteria) define _DOD and
_DOS methods to be considered a video device.
Some broken BIOSes prevented working backlight control by only defining both
for one (non-existing bus) and only _DOD for the rest. With this patch in
place the other bus definitions were considered too and backlight control
started to work again.

Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Acked-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
This commit is contained in:
Stefan Bader 2009-08-21 11:03:05 +02:00 committed by Len Brown
parent 161291396e
commit 3a1151e3f1
2 changed files with 7 additions and 2 deletions

View File

@ -1109,7 +1109,12 @@ static int acpi_video_bus_check(struct acpi_video_bus *video)
*/
/* Does this device support video switching? */
if (video->cap._DOS) {
if (video->cap._DOS || video->cap._DOD) {
if (!video->cap._DOS) {
printk(KERN_WARNING FW_BUG
"ACPI(%s) defines _DOD but not _DOS\n",
acpi_device_bid(video->device));
}
video->flags.multihead = 1;
status = 0;
}

View File

@ -84,7 +84,7 @@ long acpi_is_video_device(struct acpi_device *device)
return 0;
/* Does this device able to support video switching ? */
if (ACPI_SUCCESS(acpi_get_handle(device->handle, "_DOD", &h_dummy)) &&
if (ACPI_SUCCESS(acpi_get_handle(device->handle, "_DOD", &h_dummy)) ||
ACPI_SUCCESS(acpi_get_handle(device->handle, "_DOS", &h_dummy)))
video_caps |= ACPI_VIDEO_OUTPUT_SWITCHING;