[PATCH] drm: add docs about the IN_FORMATS plane property

[Daniel Vetter]

On Sun, Mar 29, 2020 at 02:45:08PM +0000, Simon Ser wrote:
> This is a standard property attached to planes in drm_universal_plane_init
> when drm_mode_config.allow_fb_modifiers is true.
> 
> Signed-off-by: Simon Ser <contact at emersion.fr>
> Cc: Daniel Vetter <daniel at ffwll.ch>
> Cc: Daniel Stone <daniel at fooishbar.org>
> ---
>  drivers/gpu/drm/drm_blend.c | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/drivers/gpu/drm/drm_blend.c b/drivers/gpu/drm/drm_blend.c
> index 121481f6aa71..88eedee018d3 100644
> --- a/drivers/gpu/drm/drm_blend.c
> +++ b/drivers/gpu/drm/drm_blend.c
> @@ -183,6 +183,12 @@
>   *		 plane does not expose the "alpha" property, then this is
>   *		 assumed to be 1.0
>   *
> + * IN_FORMATS:
> + *	Blob property which contains the set of buffer format and modifier
> + *	pairs supported by this plane. The blob is a drm_format_modifier_blob
> + *	struct. Without this property the plane doesn't support buffers with
> + *	modifiers. Userspace cannot change this property.

Feels mildly misplaced among the blending properties, but we don't (yet)
have a section to describe all the modifer/pixel format stuff and how it's
all supposed to work together. So for now probably as good as it gets.

Merged to drm-misc-next, thanks for your patch.
-Daniel

> + *
>   * Note that all the property extensions described here apply either to the
>   * plane or the CRTC (e.g. for the background color, which currently is not
>   * exposed and assumed to be black).
> -- 
> 2.26.0
> 
> 

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch