Re: [PATCH 02/26] drm/bridge: deprecate of_drm_find_bridge()

Louis Chauvet
2025-11-19T14:28:53Z

On 11/19/25 13:05, Luca Ceresoli wrote:
> of_drm_find_bridge() does not increment the returned bridge
> refcount. drm_of_find_bridge() is to be used as a replacement.
>
> Suggested-by: Maxime Ripard <mripard@kernel.org>
> Link: https://lore.kernel.org/dri-devel/20250319-stylish-lime-mongoose-0a18ad@houat/
> Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
> ---
> drivers/gpu/drm/drm_bridge.c | 7 +++++--
> 1 file changed, 5 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c
> index d98a7b4a83c0..6debbf20aaa8 100644
> --- a/drivers/gpu/drm/drm_bridge.c
> +++ b/drivers/gpu/drm/drm_bridge.c
> @@ -299,7 +299,7 @@ EXPORT_SYMBOL(__devm_drm_bridge_alloc);
> * @bridge: bridge control structure
> *
> * Add the given bridge to the global list of bridges, where they can be
> - * found by users via of_drm_find_bridge().
> + * found by users via drm_of_find_bridge().
> *
> * The bridge to be added must have been allocated by
> * devm_drm_bridge_alloc().
> @@ -360,7 +360,7 @@ EXPORT_SYMBOL(devm_drm_bridge_add);
> * @bridge: bridge control structure
> *
> * Remove the given bridge from the global list of registered bridges, so
> - * it won't be found by users via of_drm_find_bridge(), and add it to the
> + * it won't be found by users via drm_of_find_bridge(), and add it to the
> * lingering bridge list, to keep track of it until its allocated memory is
> * eventually freed.
> */
> @@ -1452,6 +1452,9 @@ EXPORT_SYMBOL(drm_of_find_bridge);
> *
> * @np: device node
> *
> + * This function is deprecated. Use drm_of_find_bridge() instead for proper
> + * refcounting.
> + *

I think it should be more explicit that the refcounting is not done by
this function, like:

This function is deprecated. The returned bridge is not refcounted, you
should not use drm_bridge_put(). Use drm_of_find_bridge() instead for
proper refcounting.

> * RETURNS:
> * drm_bridge control struct on success, NULL on failure
> */
>