Re: [PATCH v5 01/11] drm/bridge: drm_bridge_put(): ignore ERR_PTR

[Laurent Pinchart]

On Thu, May 07, 2026 at 03:45:19PM +0200, Luca Ceresoli wrote:
> Most functions returning a struct drm_bridge pointer currently return a
> valid pointer or NULL, but this restricts their ability to return an error
> code as an ERR_PTR describing the error kind.
> 
> In preparation to have new APIs that can return a struct drm_bridge pointer
> holding an ERR_PTR (and for those which already do) make drm_bridge_put()
> ignore ERR_PTR values, just like it ignores NULL pointers.
> 
> This will avoid annoying error checking in many places and the risk of
> missing error checks.
> 
> Suggested-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
> Link: https://lore.kernel.org/all/20260318152533.GA633439@xxxxxxxxxxxxxxxxxxxxxxxxxx/
> Suggested-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxxxxxxxx>
> Link: https://lore.kernel.org/all/omlnswxukeqgnatzdvooaashgkfcacjevkvbkm6xt33itgua2k@jcmzll2w6kdq/
> Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxxxxxxxx>
> Signed-off-by: Luca Ceresoli <luca.ceresoli@xxxxxxxxxxx>

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

> ---
> 
> Changes in v5:
> - don't change drm_bridge_get(), only drm_bridge_put() has known use cases
> 
> Changes in v4:
> - removed incorrect change to drm_bridge_clear_and_put() kdoc
> 
> Patch added in v2
> ---
>  drivers/gpu/drm/drm_bridge.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c
> index d4b3478258ec..4aaea517b436 100644
> --- a/drivers/gpu/drm/drm_bridge.c
> +++ b/drivers/gpu/drm/drm_bridge.c
> @@ -300,7 +300,7 @@ EXPORT_SYMBOL(drm_bridge_get);
>  
>  /**
>   * drm_bridge_put - Release a bridge reference
> - * @bridge: DRM bridge; if NULL this function does nothing
> + * @bridge: DRM bridge; if NULL or an ERR_PTR this function does nothing
>   *
>   * This function decrements the bridge's reference count and frees the
>   * object if the reference count drops to zero.
> @@ -310,7 +310,7 @@ EXPORT_SYMBOL(drm_bridge_get);
>   */
>  void drm_bridge_put(struct drm_bridge *bridge)
>  {
> -	if (bridge)
> +	if (!IS_ERR_OR_NULL(bridge))
>  		kref_put(&bridge->refcount, __drm_bridge_free);
>  }
>  EXPORT_SYMBOL(drm_bridge_put);
> 

-- 
Regards,

Laurent Pinchart