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    Subjectrc6+ regression - backlight reset to 0 on boot after 7c0ea45be4f114d85ee35caeead8e1660699c46f
    Commit 7c0ea45be4f114d85ee35caeead8e1660699c46f registers ACPI backlight
    even if _BQC method (query current backlight level) is missing. The effect is:

    during initialization video.c:acpi_video_device_find_cap() calls backlight_update_status(). It tries to fetch actual level via acpi_video_get_brightness() - but as _BQC is missing it just returns current value
    as stored in memory - i.e. zero, because it was never set. So effectively
    backlight_update_status() reset brightness to minimal value == 0.

    This happens on Toshiba Portege 4000. Verified by reverting commit on top of

    On a side note, it would be nice to fit backlight device into actual ACPI
    device tree instead of /devices/virtual.
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      Last update: 2008-04-02 20:57    [W:0.027 / U:6.956 seconds]
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