BACKLIGHT_MODULATION_FREQ_SHIFT   87 drivers/gpu/drm/gma500/psb_intel_reg.h #define BACKLIGHT_MODULATION_FREQ_SHIFT		(17)
BACKLIGHT_MODULATION_FREQ_SHIFT 4855 drivers/gpu/drm/i915/i915_reg.h #define   BACKLIGHT_MODULATION_FREQ_SHIFT	(17)