[PATCH v3] drm/tegra: Add zpos property for cursor planes

[Dmitry Osipenko]

16.06.2020 21:14, Thierry Reding пишет:
> From: Thierry Reding <treding at nvidia.com>
> 
> As of commit 4dc55525b095 ("drm: plane: Verify that no or all planes
> have a zpos property") a warning is emitted if there's a mix of planes
> with and without a zpos property.
> 
> On Tegra, cursor planes are always composited on top of all other
> planes, which is why they never had a zpos property attached to them.
> However, since the composition order is fixed, this is trivial to
> remedy by simply attaching an immutable zpos property to them.
> 
> v3: do not hardcode zpos for overlay planes used as cursor (Dmitry)
> v2: hardcode cursor plane zpos to 255 instead of 0 (Ville)
> 
> Reported-by: Jonathan Hunter <jonathanh at nvidia.com>
> Signed-off-by: Thierry Reding <treding at nvidia.com>
> ---
>  drivers/gpu/drm/tegra/dc.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/gpu/drm/tegra/dc.c b/drivers/gpu/drm/tegra/dc.c
> index 83f31c6e891c..04d6848d19fc 100644
> --- a/drivers/gpu/drm/tegra/dc.c
> +++ b/drivers/gpu/drm/tegra/dc.c
> @@ -957,6 +957,7 @@ static struct drm_plane *tegra_dc_cursor_plane_create(struct drm_device *drm,
>  	}
>  
>  	drm_plane_helper_add(&plane->base, &tegra_cursor_plane_helper_funcs);
> +	drm_plane_create_zpos_immutable_property(&plane->base, 255);
>  
>  	return &plane->base;
>  }
> 

Looks nice, thanks! Since you dropped all other zpos changes for other
planes and given that the other planes have 255 for the max zpos, what
about to set the cursor's zpos to 256?