Re: [PATCH v8 01/16] device property: Add fwnode_graph_get_port_by_id()

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Low] The newly added `fwnode_graph_get_port_by_id()` API takes a non-const `struct fwnode_handle *fwnode` parameter, which is inconsistent with similar API functions.
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commit 5894c0b778c62e34e52132ac30ee27b4741eb588
Author: Chen-Yu Tsai <wenst@chromium.org>

device property: Add fwnode_graph_get_port_by_id()

This commit adds the fwnode_graph_get_port_by_id() helper to obtain a
reference to a specific port firmware node by ID. This helper is intended for
cases such as USB power sequencing integration where a USB hub port is tied to
its corresponding port firmware node.

> diff --git a/drivers/base/property.c b/drivers/base/property.c
> index b136c339ddae7..68108805482de 100644
> --- a/drivers/base/property.c
> +++ b/drivers/base/property.c

[ ... ]

> @@ -1353,6 +1353,37 @@ int fwnode_graph_parse_endpoint(const struct fwnode_handle *fwnode,
>  }
>  EXPORT_SYMBOL(fwnode_graph_parse_endpoint);
>  
> +/**
> + * fwnode_graph_get_port_by_id - get the port matching a given id
> + * @fwnode: parent fwnode_handle containing the graph
> + * @id: id of the port
> + * @flags: fwnode lookup flags
> + *
> + * The caller is responsible for calling fwnode_handle_put() on the returned
> + * fwnode pointer.
> + *
> + * Does not return ports that belong to disabled devices or endpoints that
> + * are unconnected, unless FWNODE_GRAPH_DEVICE_DISABLED is passed in @flags.
> + *
> + * Does not return ports that have no endpoints.
> + *
> + * Return: A 'port' firmware node pointer with refcount incremented.
> + */
> +struct fwnode_handle *fwnode_graph_get_port_by_id(struct fwnode_handle *fwnode,
> +						  u32 id,
> +						  unsigned long flags)

[Severity: Low]
Does this function signature intentionally drop the const qualifier for the
fwnode parameter? 

This is inconsistent with similar API functions like
fwnode_graph_get_endpoint_by_id() which take a const struct fwnode_handle *.
Callers holding a const struct fwnode_handle * cannot use this helper without
an explicit cast that discards the const qualifier, which reduces API
ergonomics.

> +{
> +	struct fwnode_handle *ep;
> +
> +	ep = fwnode_graph_get_endpoint_by_id(fwnode, id, 0,
> +					     flags | FWNODE_GRAPH_ENDPOINT_NEXT);
> +	if (!ep)
> +		return NULL;
> +
> +	return fwnode_get_next_parent(ep);
> +}
> +EXPORT_SYMBOL_GPL(fwnode_graph_get_port_by_id);
> +
>  const void *device_get_match_data(const struct device *dev)
>  {
>  	return fwnode_call_ptr_op(dev_fwnode(dev), device_get_match_data, dev);

> diff --git a/include/linux/property.h b/include/linux/property.h
> index 907c790a3f013..3dbbd01a52d09 100644
> --- a/include/linux/property.h
> +++ b/include/linux/property.h

[ ... ]

> @@ -507,6 +507,8 @@ int fwnode_get_phy_mode(const struct fwnode_handle *fwnode);
>  
>  void __iomem *fwnode_iomap(struct fwnode_handle *fwnode, int index);
>  
> +struct fwnode_handle *fwnode_graph_get_port_by_id(struct fwnode_handle *fwnode, u32 id,
> +						  unsigned long flags);

[Severity: Low]
Should this declaration also use const struct fwnode_handle * for the fwnode
parameter to match the suggested change above and maintain consistency with
other fwnode_graph_* functions?

>  struct fwnode_handle *fwnode_graph_get_next_endpoint(
>  	const struct fwnode_handle *fwnode, struct fwnode_handle *prev);
>  struct fwnode_handle *

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Sashiko AI review · https://sashiko.dev/#/patchset/20260904084158.1341550-1-wenst@chromium.org?part=1