The original patches have been done by Marek: https://lists.freedesktop.org/archives/dri-devel/2016-January/099572.html
I have just adapt them to make zpos depend on plane and no more on drm core.
Since zpos range can be define per plane normalize function takes care of the min and max before compute normalized zpos value.
Benjamin Gaignard (2): drm: add generic zpos property drm: sti: use generic zpos for plane
Documentation/DocBook/gpu.tmpl | 10 ++ drivers/gpu/drm/Makefile | 2 +- drivers/gpu/drm/drm_atomic.c | 4 + drivers/gpu/drm/drm_atomic_helper.c | 6 + drivers/gpu/drm/drm_blend.c | 242 ++++++++++++++++++++++++++++++++++++ drivers/gpu/drm/drm_crtc_internal.h | 3 + drivers/gpu/drm/sti/sti_mixer.c | 2 +- drivers/gpu/drm/sti/sti_plane.c | 82 +++++------- drivers/gpu/drm/sti/sti_plane.h | 2 - include/drm/drm_crtc.h | 17 +++ 10 files changed, 314 insertions(+), 56 deletions(-) create mode 100644 drivers/gpu/drm/drm_blend.c