Comment 7 for bug 1052278

This patch is in 3.8 kernel.

commit a2a96f0c7221806c8a8072b662e6deaa119833da
Author: AceLan Kao <email address hidden>
Date: Wed Oct 3 11:26:31 2012 +0200

    asus-wmi: add display toggle quirk

    For machines with AMD graphic chips, it will send out WMI event and ACPI
    interrupt at the same time while hitting the hotkey. BIOS will notify the
    system the next display output mode throught WMI event code, so that
    windows' application can show an OSD to tell the user which mode will be
    taken effect. User can hit the display toggle key many times within 2
    seconds to choose the mode they want. After 2 seconds, WMI dirver should
    send a WMIMethod(SDSP) command to tell the BIOS which mode the user chose.
    And then BIOS will raise another ACPI interrupt to tell the system to
    really switch the display mode.

    In Linux desktop, we don't have this kind of OSD to let users to choose
    the mode they want, so we don't need to call WMIMethod(SDSP) to have
    another ACPI interrupt. To simplify the problem, we just have to ignore
    the WMI event, and let the first ACPI interrupt to send out the key event.

    For the need, here comes another quirk to add machines with this kind of
    behavior. When the WMI driver receives the display toggle WMI event, and
    found the machin is in the list, it will do nothing and let ACPI video
    driver to report the key event.

    Signed-off-by: AceLan Kao <email address hidden>
    Signed-off-by: Corentin Chary <email address hidden>
    Signed-off-by: Matthew Garrett <email address hidden>