[PATCH v2 1/4] device property: Introduce fwnode_graph_for_each_endpoint_scoped()

Laurent Pinchart laurent.pinchart at ideasonboard.com
Wed Jun 24 12:13:58 PDT 2026


Hi Frank,

Thank you for the patch.

On Wed, Jun 24, 2026 at 01:00:09PM -0400, Frank.Li at oss.nxp.com wrote:
> From: Frank Li <Frank.Li at nxp.com>
> 
> Similar to recently propose for_each_child_of_node_scoped() this new
> version of the loop macro instantiates a new local struct fwnode_handle *
> that uses the __free(fwnode_handle) auto cleanup handling so that if a
> reference to a node is held on early exit from the loop the reference will
> be released. If the loop runs to completion, the child pointer will be NULL
> and no action will be taken.
> 
> The reason this is useful is that it removes the need for
> fwnode_handle_put() on early loop exits. If there is a need to retain the
> reference, then return_ptr(child) or no_free_ptr(child) may be used to
> safely disable the auto cleanup.
> 
> Reviewed-by: Andy Shevchenko <andriy.shevchenko at linux.intel.com>
> Reviewed-by: Guoniu Zhou <guoniu.zhou at oss.nxp.com>
> Signed-off-by: Frank Li <Frank.Li at nxp.com>

Nice idea.

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

> ---
> change in v2
> - collect Andy and Guoniu's reviewed-by tags
> - fix indention
> - remove extra space in commit message
> ---
>  include/linux/property.h | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/include/linux/property.h b/include/linux/property.h
> index 14c304db46648..d51824c13d2cc 100644
> --- a/include/linux/property.h
> +++ b/include/linux/property.h
> @@ -545,6 +545,11 @@ unsigned int fwnode_graph_get_endpoint_count(const struct fwnode_handle *fwnode,
>  	for (child = fwnode_graph_get_next_endpoint(fwnode, NULL); child;	\
>  	     child = fwnode_graph_get_next_endpoint(fwnode, child))
>  
> +#define fwnode_graph_for_each_endpoint_scoped(fwnode, child)			\
> +	for (struct fwnode_handle *child __free(fwnode_handle) =		\
> +		fwnode_graph_get_next_endpoint(fwnode, NULL);		\
> +	     child; child = fwnode_graph_get_next_endpoint(fwnode, child))
> +
>  int fwnode_graph_parse_endpoint(const struct fwnode_handle *fwnode,
>  				struct fwnode_endpoint *endpoint);
>  

-- 
Regards,

Laurent Pinchart



More information about the linux-arm-kernel mailing list