drm: introduce pipe color correction properties
authorLionel Landwerlin <lionel.g.landwerlin@intel.com>
Fri, 26 Feb 2016 17:05:00 +0000 (17:05 +0000)
committerDaniel Vetter <daniel.vetter@ffwll.ch>
Tue, 8 Mar 2016 12:57:32 +0000 (13:57 +0100)
commit5488dc16fde74595a40c5d20ae52d978313f0b4e
tree555cde44405cfb8a773346f5673fe826f925a1a7
parent9b8d1e53f6da63920ba569405b8d57ddbb42a988
drm: introduce pipe color correction properties

Patch based on a previous series by Shashank Sharma.

This introduces optional properties to enable color correction at the
pipe level. It relies on 3 transformations applied to every pixels
displayed. First a lookup into a degamma table, then a multiplication
of the rgb components by a 3x3 matrix and finally another lookup into
a gamma table.

The following properties can be added to a pipe :
  - DEGAMMA_LUT : blob containing degamma LUT
  - DEGAMMA_LUT_SIZE : number of elements in DEGAMMA_LUT
  - CTM : transformation matrix applied after the degamma LUT
  - GAMMA_LUT : blob containing gamma LUT
  - GAMMA_LUT_SIZE : number of elements in GAMMA_LUT

DEGAMMA_LUT_SIZE and GAMMA_LUT_SIZE are read only properties, set by
the driver to tell userspace applications what sizes should be the
lookup tables in DEGAMMA_LUT and GAMMA_LUT.

A helper is also provided so legacy gamma correction is redirected
through these new properties.

v2: Register LUT size properties as range

v3: Fix round in drm_color_lut_get_value() helper
    More docs on how degamma/gamma properties are used

v4: Update contributors

v5: Rename CTM_MATRIX property to CTM (Doh!)
    Add legacy gamma_set atomic helper
    Describe CTM/LUT acronyms in the kernel doc

v6: Fix missing blob unref in drm_atomic_helper_crtc_reset

Signed-off-by: Shashank Sharma <shashank.sharma@intel.com>
Signed-off-by: Kumar, Kiran S <kiran.s.kumar@intel.com>
Signed-off-by: Kausal Malladi <kausalmalladi@gmail.com>
Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Acked-by: Rob Bradford <robert.bradford@intel.com>
[danvet: CrOS maintainers are also happy with the userspacde side:
https://codereview.chromium.org/1182063002/ ]
Reviewed-by: Daniel Stone <daniels@collabora.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1456506302-640-4-git-send-email-lionel.g.landwerlin@intel.com
Documentation/DocBook/gpu.tmpl
drivers/gpu/drm/drm_atomic.c
drivers/gpu/drm/drm_atomic_helper.c
drivers/gpu/drm/drm_crtc.c
drivers/gpu/drm/drm_crtc_helper.c
include/drm/drm_atomic_helper.h
include/drm/drm_crtc.h
include/drm/drm_crtc_helper.h
include/uapi/drm/drm_mode.h