Re: [PATCH v3 04/20] drm/atomic: Expand atomic_create_state expectations for drm_private_obj

Laurent Pinchart
2026-05-04T16:34:47Z

Hi Maxime,

Thank you for the patch.

On Fri, Apr 24, 2026 at 12:18:44PM +0200, Maxime Ripard wrote:
> The atomic_create_state callback documentation for planes, CRTCs, and
> connectors explicitly states the expected behaviour: the returned
> state must not be assigned to the object's state pointer, and hardware
> must not be touched.
>
> The drm_private_state_funcs.atomic_create_state documentation is
> missing this clarification. Add it for consistency.
>
> Signed-off-by: Maxime Ripard <mripard@kernel.org>

Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

> ---
> include/drm/drm_atomic.h | 5 ++++-
> 1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/include/drm/drm_atomic.h b/include/drm/drm_atomic.h
> index f03cd199aee7..f7f9c6c85f3a 100644
> --- a/include/drm/drm_atomic.h
> +++ b/include/drm/drm_atomic.h
> @@ -263,11 +263,14 @@ struct drm_private_state;
> struct drm_private_state_funcs {
> /**
> * @atomic_create_state:
> *
> * Allocates a pristine, initialized, state for the private
> - * object and returns it.
> + * object and returns it. This callback must have no side
> + * effects: in particular, the returned state must not be
> + * assigned to the object's state pointer and it must not affect
> + * the hardware state.
> *
> * RETURNS:
> *
> * A new, pristine, private state instance or an error pointer
> * on failure.

--
Regards,

Laurent Pinchart