Screen extremely dim on Dell Latitude D630 after upgrading to Linux kernel-3.14

Screen extremely dim on Dell Latitude D630 after upgrading to Linux kernel-3.14

[Marc Milgram]

[-- Attachment #1.1: Type: text/plain, Size: 1327 bytes --]

After upgrading to linux Kernel-3.14, the screen on my Dell Latitude 
D630 was nearly unreadably dim.  When I Boot the 3.13 kernel, my screen 
is bright.

I opened a Bug here: https://bugzilla.redhat.com/show_bug.cgi?id=1094066 
and others have chimed in that they have the same problem.

I bisected the kernel, and found the following commit is responsible for 
this problem:

b35684b8fa94e04f55fd38bf672b737741d2f9e2 is the first bad commit
commit b35684b8fa94e04f55fd38bf672b737741d2f9e2
Author: Jani Nikula <jani.nikula@intel.com  <mailto:jani.nikula@intel.com>>
Date:   Thu Nov 14 12:13:41 2013 +0200

     drm/i915: do full backlight setup at enable time
     
     We should now have all the information we need to do a full
     initialization of the backlight registers.
     
     v2: Keep QUIRK_NO_PCH_PWM_ENABLE for now (Imre).
     
     Signed-off-by: Jani Nikula <jani.nikula@intel.com  <mailto:jani.nikula@intel.com>>
     Reviewed-by: Imre Deak <imre.deak@intel.com  <mailto:imre.deak@intel.com>>
     Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch  <mailto:daniel.vetter@ffwll.ch>>

:040000 040000 0aae5515ca62ff1bfd2e1c2769e30c58b016ffeb 01c2f8cd145f8cf29730908d52e7e89b787a059e M	drivers

I can find my way around the kernel, but haven't hit this area before.

Any help is appreciated.

Marc Milgram


[-- Attachment #1.2: Type: text/html, Size: 1863 bytes --]

[-- Attachment #2: Type: text/plain, Size: 159 bytes --]

_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
http://lists.freedesktop.org/mailman/listinfo/intel-gfx

Re: Screen extremely dim on Dell Latitude D630 after upgrading to Linux kernel-3.14

[Jani Nikula]

On Thu, 22 May 2014, Marc Milgram <mmilgram@redhat.com> wrote:
> After upgrading to linux Kernel-3.14, the screen on my Dell Latitude 
> D630 was nearly unreadably dim.  When I Boot the 3.13 kernel, my screen 
> is bright.

Please file a new bug on DRM/Intel at [1]. Please attach
/sys/kernel/debug/dri/0/i915_opregion and dmesg with drm.debug=0xe
module parameter set.

Also include info whether max_brightness changes for you between 3.13
and 3.14.

Do the later 3.15-rc kernels work for you?


BR,
Jani.


[1] https://bugs.freedesktop.org/enter_bug.cgi?product=DRI




>
> I opened a Bug here: https://bugzilla.redhat.com/show_bug.cgi?id=1094066 
> and others have chimed in that they have the same problem.
>
> I bisected the kernel, and found the following commit is responsible for 
> this problem:
>
> b35684b8fa94e04f55fd38bf672b737741d2f9e2 is the first bad commit
> commit b35684b8fa94e04f55fd38bf672b737741d2f9e2
> Author: Jani Nikula <jani.nikula@intel.com  <mailto:jani.nikula@intel.com>>
> Date:   Thu Nov 14 12:13:41 2013 +0200
>
>      drm/i915: do full backlight setup at enable time
>      
>      We should now have all the information we need to do a full
>      initialization of the backlight registers.
>      
>      v2: Keep QUIRK_NO_PCH_PWM_ENABLE for now (Imre).
>      
>      Signed-off-by: Jani Nikula <jani.nikula@intel.com  <mailto:jani.nikula@intel.com>>
>      Reviewed-by: Imre Deak <imre.deak@intel.com  <mailto:imre.deak@intel.com>>
>      Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch  <mailto:daniel.vetter@ffwll.ch>>
>
> :040000 040000 0aae5515ca62ff1bfd2e1c2769e30c58b016ffeb 01c2f8cd145f8cf29730908d52e7e89b787a059e M	drivers
>
> I can find my way around the kernel, but haven't hit this area before.
>
> Any help is appreciated.
>
> Marc Milgram
>
> _______________________________________________
> Intel-gfx mailing list
> Intel-gfx@lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/intel-gfx

-- 
Jani Nikula, Intel Open Source Technology Center