drm/i915: gather backlight information at setup

Prepare for being able to use the information at enable.

Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index 819d0d2..4fbd073 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -163,6 +163,8 @@
 		u32 level;
 		u32 max;
 		bool enabled;
+		bool combination_mode;	/* gen 2/4 only */
+		bool active_low_pwm;
 		struct backlight_device *device;
 	} backlight;
 };