ACPI / video: only register backlight for LCD device
The firmware of ESPRIMO Mobile M9410 has two video output devices that have _BCM control method, one is the type of "External Digital Monitor" while the other is the type of "Internal/Integrated Digital Flat Panel". Only the 2nd video output device's _BCM control method works, but since we have created two and the 1st one got picked up by user space, the backlight functionality is broken. To solve this problem, only register backlight interface for "Internal/Integrated Digital Flat Panel" type video output device on this laptop. Another problem of this laptop is that the IDs listed by the _DOD method doesn't have bit 31 set, which means it doesn't follow the format specified by ACPI spec. But the value indicates that it actually follows that format so I've added a DMI quirk and a module level parameter to force use the device_id_scheme so that we can get the video output device's type to do the decision if we should register backlight interface. Link: https://bugzilla.kernel.org/show_bug.cgi?id=104121 Suggested-by: Hans de Goede <hdegoede@redhat.com> Reported-and-tested-by: Christian Scharl <zahlsum-kernelbugs@yahoo.de> Signed-off-by: Aaron Lu <aaron.lu@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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