drm/blend: Define the direction of Z position values (42770cbf) · Commits · 戴 / test

We forgot that. Proof is the one igt testcase we have: https://gitlab.freedesktop.org/drm/igt-gpu-tools/blob/master/tests/kms_atomic.c#L280 While at it also document that we have immutable zpos properties in some cases. Reported-by:

Pekka Paalanen <pekka.paalanen@collabora.com> Cc: Pekka Paalanen <pekka.paalanen@collabora.com> Reviewed-by:

Pekka Paalanen <pekka.paalanen@collabora.com> Cc: Ilia Mirkin <imirkin@alum.mit.edu> Acked-by:

drivers/gpu/drm/drm_blend.c

+6 −1

Original line number	Diff line number	Diff line
		@@ -130,7 +130,12 @@
		* Z position is set up with drm_plane_create_zpos_immutable_property() and
		* drm_plane_create_zpos_property(). It controls the visibility of overlapping
		* planes. Without this property the primary plane is always below the cursor
		* plane, and ordering between all other planes is undefined.
		* plane, and ordering between all other planes is undefined. The positive
		* Z axis points towards the user, i.e. planes with lower Z position values
		* are underneath planes with higher Z position values. Note that the Z
		* position value can also be immutable, to inform userspace about the
		* hard-coded stacking of overlay planes, see
		* drm_plane_create_zpos_immutable_property().
		*
		* pixel blend mode:
		* Pixel blend mode is set up with drm_plane_create_blend_mode_property().