diff options
| author |   Simon Ser <contact@emersion.fr> | 2020-12-11 19:46:31 +0100 |
|---|---|---|
| committer | Simon Ser <contact@emersion.fr> | 2020-12-15 16:46:31 +0100 |
| commit | 9999587b684fed59eec0847bacf0d5bbd21e0a9b (patch) | |
| tree | 5c75f88cfebfdfa791902056ed2bc0b85e8737a9 /drivers/gpu/drm/drm_plane.c | |
| parent | drm/omap: Delete useless kfree code (diff) | |
| download | linux-dev-9999587b684fed59eec0847bacf0d5bbd21e0a9b.tar.xz linux-dev-9999587b684fed59eec0847bacf0d5bbd21e0a9b.zip | |
drm: rework description of primary and cursor planes
The previous wording could be understood by user-space evelopers as "a
primary/cursor plane is only compatible with a single CRTC" [1].
Reword the planes description to make it clear the DRM-internal
drm_crtc.primary and drm_crtc.cursor planes are for legacy uAPI.
[1]: https://github.com/swaywm/wlroots/pull/2333#discussion_r456788057
Signed-off-by: Simon Ser <contact@emersion.fr>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Pekka Paalanen <pekka.paalanen@collabora.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201211184634.74534-1-contact@emersion.fr
Diffstat (limited to 'drivers/gpu/drm/drm_plane.c')
| -rw-r--r-- | drivers/gpu/drm/drm_plane.c | 16 |
1 files changed, 9 insertions, 7 deletions
diff --git a/drivers/gpu/drm/drm_plane.c b/drivers/gpu/drm/drm_plane.c index 385801dd21f9..5d33ca9f0032 100644 --- a/drivers/gpu/drm/drm_plane.c +++ b/drivers/gpu/drm/drm_plane.c @@ -49,14 +49,16 @@ * &struct drm_plane (possibly as part of a larger structure) and registers it * with a call to drm_universal_plane_init(). * - * Cursor and overlay planes are optional. All drivers should provide one - * primary plane per CRTC to avoid surprising userspace too much. See enum - * drm_plane_type for a more in-depth discussion of these special uapi-relevant - * plane types. Special planes are associated with their CRTC by calling - * drm_crtc_init_with_planes(). - * * The type of a plane is exposed in the immutable "type" enumeration property, - * which has one of the following values: "Overlay", "Primary", "Cursor". + * which has one of the following values: "Overlay", "Primary", "Cursor" (see + * enum drm_plane_type). A plane can be compatible with multiple CRTCs, see + * &drm_plane.possible_crtcs. + * + * Legacy uAPI doesn't expose the primary and cursor planes directly. DRM core + * relies on the driver to set the primary and optionally the cursor plane used + * for legacy IOCTLs. This is done by calling drm_crtc_init_with_planes(). All + * drivers should provide one primary plane per CRTC to avoid surprising legacy + * userspace too much. */ static unsigned int drm_num_planes(struct drm_device *dev) |