• Lv Zheng's avatar
    Revert "ACPI / button: Remove lid_init_state=method mode" · f369fdf4
    Lv Zheng authored
    This reverts commit ecb10b69.
    The only expected ACPI control method lid device's usage model is
     1. Listen to the lid notification,
     2. Evaluate _LID after being notified by BIOS,
     3. Suspend the system (if users configure to do so) after seeing "close".
    It's not ensured that BIOS will notify OS after boot/resume, and
    it's not ensured that BIOS will always generate "open" event upon
    opening the lid.
    But there are 2 wrong usage models:
     1. When the lid device is responsible for suspend/resume the system,
        userspace requires to see "open" event to be paired with "close" after
        the system is resumed, or it will suspend the system again.
     2. When an external monitor connects to the laptop attached docks,
        userspace requires to see "close" event after the system is resumed so
        that it can determine whether the internal display should remain dark
        and the external display should be lit on.
    After we made default kernel behavior to be suitable for usage model 1,
    users of usage model 2 start to report regressions for such behavior
    Reversion of button.lid_init_state=method doesn't actually reverts to old
    default behavior as doing so can enter a regression loop, but facilitates
    users to work the reported regressions around with
    Fixes: ecb10b69 (ACPI / button: Remove lid_init_state=method mode)
    Cc: 4.11+ <stable@vger.kernel.org> # 4.11+
    Link: https://bugzilla.kernel.org/show_bug.cgi?id=195455
    Link: https://bugzilla.redhat.com/show_bug.cgi?id=1430259Tested-by: default avatarSteffen Weber <steffen.weber@gmail.com>
    Tested-by: default avatarJulian Wiedmann <julian.wiedmann@jwi.name>
    Reported-by: default avatarJoachim Frieben <jfrieben@hotmail.com>
    Signed-off-by: default avatarLv Zheng <lv.zheng@intel.com>
    Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
acpi-lid.txt 4.92 KB