Seeing this on boot: [drm:intel_panel_setup_backlight] *ERROR* Failed to get maximum backlight value Is this really such a critical error? 00:02.0 VGA compatible controller: Intel Corporation 82852/855GM Integrated Graphics Device (rev 02) [ 1.418171] [drm] Initialized drm 1.1.0 20060810 [ 1.472955] fb: conflicting fb hw usage inteldrmfb vs EFI VGA - removing generic driver [ 1.476903] [drm] Supports vblank timestamp caching Rev 1 (10.10.2010). [ 1.476909] [drm] Driver supports precise vblank timestamp query. [ 1.476999] [drm] applying pipe a force quirk [ 1.515239] [drm:intel_panel_setup_backlight] *ERROR* Failed to get maximum backlight value [ 1.784954] [drm] initialized overlay support [ 1.884551] fbcon: inteldrmfb (fb0) is primary device [ 2.414034] fb0: inteldrmfb frame buffer device [ 2.414039] drm: registered panic notifier [ 2.414084] [drm] Initialized i915 1.6.0 20080730 for 0000:00:02.0 on minor 0 3.6.1-1.fc17.i686 mesa-dri-drivers-8.0.4-1.fc17.i686
Before we simply shut up this warning, just to check: Is anything going wrong with your backlight?
The too verbose error message is my bad, introduced in commit 28dcc2d60cb570d9f549c329b2f51400553412a1 Author: Jani Nikula <jani.nikula@intel.com> Date: Mon Sep 3 16:25:12 2012 +0300 drm/i915: do not expose a dysfunctional backlight interface to userspace Maybe a DRM_INFO would suffice.
Actually at this moment in time, we can probably just make it DRM_DEBUG() since we know the problem exists, and thanks to your patches we no longer expose the dysfunctional interface. I added the original line simply because I was not aware of any BIOS that would leave those PWM registers unset.
Fix merged into -fixes commit e86b618547bb0c7db96aa70491112f032b3bec1c Author: Jani Nikula <jani.nikula@intel.com> Date: Thu Oct 25 10:57:38 2012 +0300 drm/i915: be less verbose about inability to provide vendor backlight
Thank for the patch! But I can't understand, why he doesn't included in 3.6.7 ?
(In reply to comment #5) > Thank for the patch! > But I can't understand, why he doesn't included in 3.6.7 ? Because that's how the kernel patchflow works. First something needs to land in upstream and then, if it doesn't blow up or cause other trouble, it can be backported.
I am seeing the same error line in 3.6.10. [drm:intel_panel_setup_backlight] *ERROR* Failed to get maximum backlight value [drm] initialized overlay support fbcon: inteldrmfb (fb0) is primary device tsc: Refined TSC clocksource calibration: 1729.517 MHz Switching to clocksource tsc i915: fixme: max PWM is zero Also, there is this fixme line. Please have a look.
This patch is already included in 3.7
What bug do you want fixed in 3.6.y, for this is just a warning?
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