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authorLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>2020-04-04 20:43:01 +0300
committerLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>2020-05-14 02:10:52 +0300
commit4dc55525b09514737bb17eb437b2f4d3c6740d8a (patch)
tree74599e6aa0c66d535ef533c4acedf28e88eab5f2 /drivers/gpu/drm/drm_plane.c
parent07de3d31f15fdc51c3b9c30e347573499cf08aeb (diff)
downloadlinux-4dc55525b09514737bb17eb437b2f4d3c6740d8a.tar.xz
drm: plane: Verify that no or all planes have a zpos property
The zpos property is used by userspace to sort the order of planes. While the property is not mandatory for drivers to implement, mixing planes with and without zpos confuses userspace, and shall not be allowed. Clarify this in the documentation and warn at runtime if the drivers mixes planes with and without zpos properties. Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Acked-by: Sam Ravnborg <sam@ravnborg.org> Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Diffstat (limited to 'drivers/gpu/drm/drm_plane.c')
-rw-r--r--drivers/gpu/drm/drm_plane.c9
1 files changed, 9 insertions, 0 deletions
diff --git a/drivers/gpu/drm/drm_plane.c b/drivers/gpu/drm/drm_plane.c
index d6ad60ab0d38..4af173ced327 100644
--- a/drivers/gpu/drm/drm_plane.c
+++ b/drivers/gpu/drm/drm_plane.c
@@ -289,6 +289,8 @@ EXPORT_SYMBOL(drm_universal_plane_init);
int drm_plane_register_all(struct drm_device *dev)
{
+ unsigned int num_planes = 0;
+ unsigned int num_zpos = 0;
struct drm_plane *plane;
int ret = 0;
@@ -297,8 +299,15 @@ int drm_plane_register_all(struct drm_device *dev)
ret = plane->funcs->late_register(plane);
if (ret)
return ret;
+
+ if (plane->zpos_property)
+ num_zpos++;
+ num_planes++;
}
+ drm_WARN(dev, num_zpos && num_planes != num_zpos,
+ "Mixing planes with and without zpos property is invalid\n");
+
return 0;
}