Re: [PATCH v2 07/28] drm/bridge: Implement atomic_print_state

[Jani Nikula <jani.nikula@linux.intel.com>]

On Thu, 23 Apr 2026, Maxime Ripard <mripard@kernel.org> wrote:
> Bridges have some fields in their state worth printing, but we don't
> provide an atomic_print_state implementation to show those fields.
>
> Provide one.
>
> Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
> Signed-off-by: Maxime Ripard <mripard@kernel.org>
> ---
>  drivers/gpu/drm/drm_bridge.c | 21 +++++++++++++++++++++
>  1 file changed, 21 insertions(+)
>
> diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c
> index 5b8e171afbe5..fba440bddcb3 100644
> --- a/drivers/gpu/drm/drm_bridge.c
> +++ b/drivers/gpu/drm/drm_bridge.c
> @@ -506,14 +506,35 @@ drm_bridge_atomic_create_priv_state(struct drm_private_obj *obj)
>  		return ERR_CAST(state);
>  
>  	return &state->base;
>  }
>  
> +static void
> +drm_bridge_atomic_print_priv_state(struct drm_printer *p,
> +				   const struct drm_private_state *s)
> +{
> +	const struct drm_bridge_state *state = drm_priv_to_bridge_state(s);
> +	struct drm_bridge *bridge = drm_priv_to_bridge(s->obj);
> +
> +	if (bridge->of_node)
> +		drm_printf(p, "bridge: %ps (%pOFfc)\n", bridge->funcs, bridge->of_node);
> +	else
> +		drm_printf(p, "bridge: %ps\n", bridge->funcs);
> +
> +	drm_printf(p, "\tinput bus configuration:");
> +	drm_printf(p, "\t\tcode: %04x", state->input_bus_cfg.format);
> +	drm_printf(p, "\t\tflags: %08x", state->input_bus_cfg.flags);
> +	drm_printf(p, "\toutput bus configuration:");
> +	drm_printf(p, "\t\tcode: %04x", state->output_bus_cfg.format);
> +	drm_printf(p, "\t\tflags: %08x", state->output_bus_cfg.flags);

Nitpick, please see drm_printf_indent(). Not having the \t's in the
format strings makes them easier on the eyes.

BR,
Jani.

> +}
> +
>  static const struct drm_private_state_funcs drm_bridge_priv_state_funcs = {
>  	.atomic_create_state = drm_bridge_atomic_create_priv_state,
>  	.atomic_duplicate_state = drm_bridge_atomic_duplicate_priv_state,
>  	.atomic_destroy_state = drm_bridge_atomic_destroy_priv_state,
> +	.atomic_print_state = drm_bridge_atomic_print_priv_state,
>  };
>  
>  /**
>   * drm_private_obj_is_bridge - check if a private object backs a bridge
>   * @obj: private object to check

-- 
Jani Nikula, Intel