diff --git a/drivers/gpu/drm/drm_color_mgmt.c b/drivers/gpu/drm/drm_color_mgmt.c
index d28ffdd2b9298113770621310de332c79774f6f7..6543ebde501a7f5c242917d3124512eb3d45cea8 100644
--- a/drivers/gpu/drm/drm_color_mgmt.c
+++ b/drivers/gpu/drm/drm_color_mgmt.c
@@ -41,6 +41,10 @@
  *	nor use all the elements of the LUT (for example the hardware might
  *	choose to interpolate between LUT[0] and LUT[4]).
  *
+ *	Setting this to NULL (blob property value set to 0) means a
+ *	linear/pass-thru gamma table should be used. This is generally the
+ *	driver boot-up state too.
+ *
  * “DEGAMMA_LUT_SIZE”:
  *	Unsinged range property to give the size of the lookup table to be set
  *	on the DEGAMMA_LUT property (the size depends on the underlying
@@ -54,6 +58,10 @@
  *	lookup through the gamma LUT. The data is interpreted as a struct
  *	&drm_color_ctm.
  *
+ *	Setting this to NULL (blob property value set to 0) means a
+ *	unit/pass-thru matrix should be used. This is generally the driver
+ *	boot-up state too.
+ *
  * “GAMMA_LUT”:
  *	Blob property to set the gamma lookup table (LUT) mapping pixel data
  *	after the transformation matrix to data sent to the connector. The
@@ -62,6 +70,10 @@
  *	nor use all the elements of the LUT (for example the hardware might
  *	choose to interpolate between LUT[0] and LUT[4]).
  *
+ *	Setting this to NULL (blob property value set to 0) means a
+ *	linear/pass-thru gamma table should be used. This is generally the
+ *	driver boot-up state too.
+ *
  * “GAMMA_LUT_SIZE”:
  *	Unsigned range property to give the size of the lookup table to be set
  *	on the GAMMA_LUT property (the size depends on the underlying hardware).