1. 19 9月, 2007 1 次提交
    • Z
      ACPI: video: _DOS=0 by default to prevent hotkey hang · a21101c4
      Zhang Rui 提交于
      In the past, the Linux/ACPI video driver invoked _DOS
      (Display Output Switch) with the parameter 1
      to tell the BIOS to switch the video output display for us.
      
      But this conflicts with Linux native graphics drivers,
      and can cause all sorts of issues, including hanging the system.
      
      http://bugzilla.kernel.org/show_bug.cgi?id=6001
      
      Here we change the Linux default to evaluate _DOS=0,
      which tells the BIOS to simply send us a hotkey event
      and not touch the graphics hardware.
      
      The acpi video driver sends the display switch hotkey
      event up through the intput layer, and X can interpret
      that and use its native graphics driver to switch the display.
      
      For the case where Linux has no native graphics driver running,
      or the graphics driver doesn't know how to switch video and
      the BIOS (safely) does, the previous behaviour can be restored with:
      
      # echo 1 > /proc/acpi/video/*/DOS
      Signed-off-by: NZhang Rui <rui.zhang@intel.com>
      Signed-off-by: NLen Brown <len.brown@intel.com>
      a21101c4
  2. 17 9月, 2007 24 次提交
  3. 16 9月, 2007 12 次提交
  4. 15 9月, 2007 3 次提交