diff options
Diffstat (limited to 'include/drm/drm_plane.h')
| -rw-r--r-- | include/drm/drm_plane.h | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/include/drm/drm_plane.h b/include/drm/drm_plane.h index 43cf193e54d6..8b4dc62470ff 100644 --- a/include/drm/drm_plane.h +++ b/include/drm/drm_plane.h @@ -47,8 +47,14 @@ struct drm_crtc; * @src_h: height of visible portion of plane (in 16.16) * @rotation: rotation of the plane * @zpos: priority of the given plane on crtc (optional) + * Note that multiple active planes on the same crtc can have an identical + * zpos value. The rule to solving the conflict is to compare the plane + * object IDs; the plane with a higher ID must be stacked on top of a + * plane with a lower ID. * @normalized_zpos: normalized value of zpos: unique, range from 0 to N-1 - * where N is the number of active planes for given crtc + * where N is the number of active planes for given crtc. Note that + * the driver must call drm_atomic_normalize_zpos() to update this before + * it can be trusted. * @src: clipped source coordinates of the plane (in 16.16) * @dst: clipped destination coordinates of the plane * @visible: visibility of the plane |