diff options
| author | Daniel Vetter <daniel.vetter@ffwll.ch> | 2016-09-26 11:04:37 +0200 |
|---|---|---|
| committer | Daniel Vetter <daniel.vetter@ffwll.ch> | 2016-11-15 22:39:48 +0100 |
| commit | 717fd813b8130e36971205af09b0e6a5e6d3c433 (patch) | |
| tree | 03c8af9fcff2271982f2ef5154975a743a2a4963 /drivers/gpu/drm/drm_color_mgmt.c | |
| parent | edd420eaffb3a618ddc8740683abc039ad97237f (diff) | |
drm/color: document NULL values and default settings better
Brought up in a discussion for enabling gamma on fsl-dcu.
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Meng Yi <meng.yi@nxp.com>
Cc: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20160926090437.22676-1-daniel.vetter@ffwll.ch
Diffstat (limited to 'drivers/gpu/drm/drm_color_mgmt.c')
| -rw-r--r-- | drivers/gpu/drm/drm_color_mgmt.c | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/drivers/gpu/drm/drm_color_mgmt.c b/drivers/gpu/drm/drm_color_mgmt.c index d28ffdd2b929..6543ebde501a 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). |