Some minor comments below, apart from that looks good!
Typo in the commit title: s/supports/support/
> diff --git a/include/uapi/drm/drm_mode.h b/include/uapi/drm/drm_mode.h
> index 5ef87cb5b242..316c643e0dea 100644
> --- a/include/uapi/drm/drm_mode.h
> +++ b/include/uapi/drm/drm_mode.h
> @@ -913,6 +913,27 @@ enum drm_colorop_type {
> * property.
> */
> DRM_COLOROP_MULTIPLIER,
> + /**
> + * @DRM_COLOROP_3D_LUT:
> + *
> + * A 3D LUT of &drm_color_lut entries,
> + * packed into a blob via the DATA property. The driver's expected
> + * LUT size is advertised via the SIZE property.
> + */
These are user-space docs (in uapi/), so would be nice to include more details
here. What is SIZE, the full size or just a single dimension? Seems to be the
latter. How are the blob entries laid out?
> + DRM_COLOROP_3D_LUT,
> +};
> +
> +/**
> + * enum drm_colorop_lut3d_interpolation_type - type of 3DLUT interpolation
> + *
Nit: stray empty line
> + */
> +enum drm_colorop_lut3d_interpolation_type {
> + /**
> + * @DRM_COLOROP_LUT3D_INTERPOLATION_TETRAHEDRAL:
> + *
> + * Tetrahedral 3DLUT interpolation
> + */
> + DRM_COLOROP_LUT3D_INTERPOLATION_TETRAHEDRAL,
> };
