diff options
Diffstat (limited to 'drivers/gpu/drm/drm_plane.c')
| -rw-r--r-- | drivers/gpu/drm/drm_plane.c | 18 |
1 files changed, 10 insertions, 8 deletions
diff --git a/drivers/gpu/drm/drm_plane.c b/drivers/gpu/drm/drm_plane.c index e6231947f987..49b0a8b9ac02 100644 --- a/drivers/gpu/drm/drm_plane.c +++ b/drivers/gpu/drm/drm_plane.c @@ -40,7 +40,7 @@ * A plane represents an image source that can be blended with or overlayed on * top of a CRTC during the scanout process. Planes take their input data from a * &drm_framebuffer object. The plane itself specifies the cropping and scaling - * of that image, and where it is placed on the visible are of a display + * of that image, and where it is placed on the visible area of a display * pipeline, represented by &drm_crtc. A plane can also have additional * properties that specify how the pixels are positioned and blended, like * rotation or Z-position. All these properties are stored in &drm_plane_state. @@ -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 must provide one primary plane per CRTC to avoid surprising legacy + * userspace too much. */ static unsigned int drm_num_planes(struct drm_device *dev) |