Re: [PATCH v4 03/10] software node: allow referencing firmware nodes

From: Andy Shevchenko
Date: Mon Nov 03 2025 - 04:49:42 EST


On Mon, Nov 03, 2025 at 10:35:23AM +0100, Bartosz Golaszewski wrote:
>
> At the moment software nodes can only reference other software nodes.
> This is a limitation for devices created, for instance, on the auxiliary
> bus with a dynamic software node attached which cannot reference devices
> the firmware node of which is "real" (as an OF node or otherwise).
>
> Make it possible for a software node to reference all firmware nodes in
> addition to static software nodes. To that end: add a second pointer to
> struct software_node_ref_args of type struct fwnode_handle. The core
> swnode code will first check the swnode pointer and if it's NULL, it
> will assume the fwnode pointer should be set. Rework the helper macros
> and deprecate the existing ones whose names don't indicate the reference
> type.
>
> Software node graphs remain the same, as in: the remote endpoints still
> have to be software nodes.

...

> + /*
> + * A software node can reference other software nodes or firmware
> + * nodes (which are the abstraction layer sitting on top of them).
> + * This is done to ensure we can create references to static software
> + * nodes before they're registered with the firmware node framework.
> + * At the time the reference is being resolved, we expect the swnodes
> + * in question to already have been registered and to be backed by
> + * a firmware node. This is why we use the fwnode API below to read the

A nit-pick (since anyway it requires a new version): move 'the' to the next
line to make them more equal in the length.

> + * relevant properties and bump the reference count.
> + */

...

> -#define SOFTWARE_NODE_REFERENCE(_ref_, ...) \
> +#define __SOFTWARE_NODE_REF(_ref, ...) \

No, NAK. The renaming of the parameters is not related to this change _at all_.
Why do you change established style here? Did I miss your answer to my question
in the previous rounds?

> (const struct software_node_ref_args) { \
> - .node = _ref_, \
> + .swnode = _Generic(_ref, \
> + const struct software_node *: _ref, \
> + default: NULL), \
> + .fwnode = _Generic(_ref, \
> + struct fwnode_handle *: _ref, \
> + default: NULL), \
> .nargs = COUNT_ARGS(__VA_ARGS__), \
> .args = { __VA_ARGS__ }, \
> }

...

> +#define SOFTWARE_NODE_REF_SWNODE(_ref, ...) \
> + __SOFTWARE_NODE_REF(_ref, __VA_ARGS__)
> +
> +#define SOFTWARE_NODE_REF_FWNODE(_ref, ...) \
> + __SOFTWARE_NODE_REF(_ref, __VA_ARGS__)
> +
> +/* DEPRECATED, use SOFTWARE_NODE_REF_SWNODE() instead. */
> +#define SOFTWARE_NODE_REFERENCE(_ref, ...) \
> + SOFTWARE_NODE_REF_SWNODE(_ref, __VA_ARGS__)

Now, useless.

...


> -#define PROPERTY_ENTRY_REF(_name_, _ref_, ...) \
> +#define __PROPERTY_ENTRY_REF(_type, _name, _ref, ...) \
> (struct property_entry) { \
> - .name = _name_, \
> + .name = _name, \
> .length = sizeof(struct software_node_ref_args), \
> .type = DEV_PROP_REF, \
> - { .pointer = &SOFTWARE_NODE_REFERENCE(_ref_, ##__VA_ARGS__), }, \
> + { .pointer = &_type(_ref, ##__VA_ARGS__), }, \
> }

Do we need this now? I assume that _Generic() takes case of this.

...

> +#define PROPERTY_ENTRY_REF_SWNODE(_name, _ref, ...) \
> + __PROPERTY_ENTRY_REF(SOFTWARE_NODE_REF_SWNODE, \
> + _name, _ref, __VA_ARGS__)
> +
> +#define PROPERTY_ENTRY_REF_FWNODE(_name, _ref, ...) \
> + __PROPERTY_ENTRY_REF(SOFTWARE_NODE_REF_FWNODE, \
> + _name, _ref, __VA_ARGS__)
> +
> +/* DEPRECATED, use PROPERTY_ENTRY_REF_SWNODE() instead. */
> +#define PROPERTY_ENTRY_REF(_name, _ref, ...) \
> + PROPERTY_ENTRY_REF_SWNODE(_name, _ref, __VA_ARGS__)

Seems like useless churn.

--
With Best Regards,
Andy Shevchenko