[Ubuntu Wiki] Update of "Kernel/Debugging/Backlight" by penalvch

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The "Kernel/Debugging/Backlight" page has been changed by penalvch:
http://wiki.ubuntu.com/Kernel/Debugging/Backlight?action=diff&rev1=24&rev2=25

Comment:
As per https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1261853/comments/18 added video.use_native_backlight=1 kernel parameter check request.

     * ls -la /sys/class/backlight/intel_backlight/ > lslabacklight
     * {{{echo 8 > /sys/class/backlight/intel_backlight/brightness}}}
      * Please comment on if the brightness changes.
-  * Reboot with kernel parameter video.use_bios_initial_backlight=0 and make a comment on if you can now alter the backlight with hotkeys or a brightness applet.
+  * Reboot with just kernel parameter video.use_bios_initial_backlight=0 and make a comment on if you can now alter the backlight with hotkeys or a brightness applet.
+  * Reboot with just kernel parameter video.use_native_backlight=1 and and make a comment on if you can now alter the backlight with hotkeys or a brightness applet.
   * If your backlight hotkeys are Fn+Left and Fn+Right, add kernel parameter atkbd.softraw=0 to /boot/grub/menu.lst . Then, switch to any console, e.g. Ctrl+Alt+F1, login by root account and execute:<<BR>> {{{showkey -s}}} <<BR>> <<BR>> Then, press Fn+Left and Fn+Right key to check the code that shows up on screen. Post the results to the report. For example: <<BR>> <<BR>> Fn+Left: <<BR>> 0xe0 0x4c 0xe0 0xcc <<BR>> <<BR>> Fn+Right: <<BR>> 0xe0 0x54 0xe0 0xd4
  
  === Thinkpads ===
  
-  * Add kernel parameters thinkpad-acpi.brightness_enable=1 acpi_backlight=vendor to /boot/grub/menu.lst . Execute: <<BR>> {{{sudo update grub}}} <<BR>> <<BR>> Restart, and comment on if brightness may be changed via hotkeys and/or brightness applet.
+  * Add just kernel parameters thinkpad-acpi.brightness_enable=1 acpi_backlight=vendor to /boot/grub/menu.lst . Execute: <<BR>> {{{sudo update grub}}} <<BR>> <<BR>> Restart, and comment on if brightness may be changed via hotkeys and/or brightness applet.
   * As well, execute the following and post results to your report: <<BR>> {{{lsmod | grep thinkpad_acpi}}}
  
  = Diagnostic Techniques =