On 2022-02-07 11:34, Maxime Ripard wrote:
> From: Dave Stevenson <dave.stevenson@xxxxxxxxxxxxxxx>
>
> The drm_plane_create_zpos_property() function asks for an initial value,
> and will set the associated plane state variable with that value if a
> state is present.
>
> However, that function is usually called at a time where there's no
> state yet. Since the drm_plane_state reset helper doesn't take care of
> reading that value when it's called, it means that in most cases the
> initial value will be 0, or the drivers will have to work around it.
>
> Let's add some code in __drm_atomic_helper_plane_state_reset() to get
> the initial zpos value if the property has been attached in order to fix
> this.
>
> Signed-off-by: Dave Stevenson <dave.stevenson@xxxxxxxxxxxxxxx>
> Signed-off-by: Maxime Ripard <maxime@xxxxxxxxxx>
Reviewed-by: Harry Wentland <harry.wentland@xxxxxxx>
Harry
> ---
> drivers/gpu/drm/drm_atomic_state_helper.c | 11 +++++++++++
> 1 file changed, 11 insertions(+)
>
> diff --git a/drivers/gpu/drm/drm_atomic_state_helper.c b/drivers/gpu/drm/drm_atomic_state_helper.c
> index ddcf5c2c8e6a..1412cee404ca 100644
> --- a/drivers/gpu/drm/drm_atomic_state_helper.c
> +++ b/drivers/gpu/drm/drm_atomic_state_helper.c
> @@ -243,11 +243,22 @@ EXPORT_SYMBOL(drm_atomic_helper_crtc_destroy_state);
> void __drm_atomic_helper_plane_state_reset(struct drm_plane_state *plane_state,
> struct drm_plane *plane)
> {
> + u64 val;
> +
> plane_state->plane = plane;
> plane_state->rotation = DRM_MODE_ROTATE_0;
>
> plane_state->alpha = DRM_BLEND_ALPHA_OPAQUE;
> plane_state->pixel_blend_mode = DRM_MODE_BLEND_PREMULTI;
> +
> + if (plane->zpos_property) {
> + if (!drm_object_property_get_default_value(&plane->base,
> + plane->zpos_property,
> + &val)) {
> + plane_state->zpos = val;
> + plane_state->normalized_zpos = val;
> + }
> + }
> }
> EXPORT_SYMBOL(__drm_atomic_helper_plane_state_reset);
>
