DP_AUX_CH_CTL_MESSAGE_SIZE_MASK 1465 drivers/gpu/drm/gma500/psb_intel_reg.h #define   DP_AUX_CH_CTL_MESSAGE_SIZE_MASK    (0x1f << 20)
DP_AUX_CH_CTL_MESSAGE_SIZE_MASK 5550 drivers/gpu/drm/i915/i915_reg.h #define   DP_AUX_CH_CTL_MESSAGE_SIZE_MASK    (0x1f << 20)