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Blob property to set the gamma lookup table (LUT) mapping pixel data after the transformation matrix to data sent to the connector. The data is interpreted as an array of &struct drm_color_lut elements. Hardware might choose not to use the full precision of the LUT elements nor use all the elements of the LUT (for example the hardware might choose to interpolate between LUT and LUT). 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. Drivers can access this blob through &drm_crtc_state.gamma_lut. Note that for mostly historical reasons stemming from Xorg heritage, this is also used to store the color map (also sometimes color lut, CLUT or color palette) for indexed formats like DRM_FORMAT_C8.