Re: Regression: i915 blank issue on kernel 3.1.0-rc3

[Alex Davis <alex14641@yahoo.com>]

.From: Keith Packard <keithp@keithp.com>
>> The following patch fixed my backlight issues:
>> 
>> diff --git a/drivers/gpu/drm/i915/intel_panel.c b/drivers/gpu/drm/i915/intel_panel.c
>> index a9e0c7b..6f56676 100644
>> --- a/drivers/gpu/drm/i915/intel_panel.c
>> +++ b/drivers/gpu/drm/i915/intel_panel.c
>> @@ -262,8 +262,6 @@ void intel_panel_disable_backlight(struct drm_device *dev)
>>          dev_priv->backlight_level = intel_panel_get_backlight(dev);
>>          dev_priv->backlight_enabled = false;
>>      }
>> -
>> -    intel_panel_set_backlight(dev, 0);
>>  }
>>  
>>  void intel_panel_enable_backlight(struct drm_device *dev)
>> 
>> I've been using it since yesterday morning with no issues.
>
>Matthew -- if we cannot resolve this backlight issue, we're going to
>need to disable the new backlight code for 3.1. Do you want to try and
>fix it? Or should we bail for now?

By 'disable', do you mean revert? If so, I would the like chance to submit a patch that adds a boot parameter 
for the driver to disable the backlight by default, e.g: i915_disable_bl. Once the issues are sorted, the
parameter could be removed.