Commit ca40cfc8 authored by Thierry Reding's avatar Thierry Reding

drm/atomic-helper: Make zpos property kerneldoc less misleading

kerneldoc for drm_plane_create_zpos_property() says that the DRM core
will automatically calculate the normalized zpos values, but it doesn't
actually do that anymore since commit 38d868e4 ("drm: Don't force
all planes to be added to the state due to zpos"). Instead, drivers are
supposed to explicitly call the drm_atomic_normalize_zpos() function.
Change the kerneldoc comment to reflect that.

v2: reference the commit that introduced the kerneldoc unclarity
Reviewed-by: default avatarDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: default avatarThierry Reding <treding@nvidia.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171120150959.26913-1-thierry.reding@gmail.com
parent 170178fe
...@@ -214,9 +214,11 @@ EXPORT_SYMBOL(drm_rotation_simplify); ...@@ -214,9 +214,11 @@ EXPORT_SYMBOL(drm_rotation_simplify);
* This function initializes generic mutable zpos property and enables support * This function initializes generic mutable zpos property and enables support
* for it in drm core. Drivers can then attach this property to planes to enable * for it in drm core. Drivers can then attach this property to planes to enable
* support for configurable planes arrangement during blending operation. * support for configurable planes arrangement during blending operation.
* Once mutable zpos property has been enabled, the DRM core will automatically * Drivers that attach a mutable zpos property to any plane should call the
* calculate &drm_plane_state.normalized_zpos values. Usually min should be set * drm_atomic_normalize_zpos() helper during their implementation of
* to 0 and max to maximal number of planes for given crtc - 1. * &drm_mode_config_funcs.atomic_check(), which will update the normalized zpos
* values and store them in &drm_plane_state.normalized_zpos. Usually min
* should be set to 0 and max to maximal number of planes for given crtc - 1.
* *
* If zpos of some planes cannot be changed (like fixed background or * If zpos of some planes cannot be changed (like fixed background or
* cursor/topmost planes), driver should adjust min/max values and assign those * cursor/topmost planes), driver should adjust min/max values and assign those
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