Re: [PATCH 1/2] driver core: provide device_match_fwnode_ext()

[Bartosz Golaszewski]

On Thu, 19 Feb 2026 20:58:32 +0100, Andy Shevchenko
<andriy.shevchenko@xxxxxxxxxxxxxxx> said:
> On Thu, Feb 19, 2026 at 05:31:22PM +0100, Bartosz Golaszewski wrote:
>> Provide an extended variant of device_match_fwnode() that also tries to
>> match the device's secondary fwnode.
>
> ...
>
>> +int device_match_fwnode_ext(struct device *dev, const void *fwnode)
>> +{
>> +	struct fwnode_handle *dev_node = dev_fwnode(dev);
>
>> +	if (!fwnode)
>
> IS_ERR_OR_NULL()
> If supplied @fwnode is secondary, it might be an error pointer.
>

I mirrored existing device_match_fwnode(), should it be fixed too?

>> +		return 0;
>
>> +	if (dev_node == fwnode)
>> +		return 1;
>> +
>> +	return fwnode_is_primary(dev_node) && dev_node->secondary == fwnode;
>> +}
>
> I think we can refactor this.
>
> 	struct fwnode_handle *node;
>
> // I would name it like this, because in 3 cases in drivers/base/property.c
> // 2 with node and 1 with dev_node when the same API is called.
>

Haystack's node is "node" and the needle is "fwnode"? Seems confusing to me.

> 	if (IS_ERR(fwnode))
> 		return 0;
>
> 	if (device_match_fwnode(dev, fwnode)) // NULL check is inside
> 		return 1;
>

Yeah, and it too can be supplied a secondary fwnode. Let's say we resolve
a reference to a secondary software node and try to lookup a GPIO through it,
we'll end up with an IS_ERR() fwnode with existing code, right?

> 	node = dev_fwnode(dev);
>
> 	return fwnode_is_primary(node) && node->secondary == fwnode; // NULL check is inside
>
>
>> +	if (!fwnode)
>> +		return 0;
>
>> +	if (dev_node == fwnode)
>> +		return 1;
>> +
>> +	return fwnode_is_primary(dev_node) && dev_node->secondary == fwnode;
>> +}
>
>
> ...
>
>> +int device_match_fwnode_ext(struct device *dev, const void *fwnode);
>
> Perhaps ext --> or_secondary ?
>

I thought about it but it would make it sound like it only matches the
secondary to me. Maybe device_match_all_fwnodes()? Would be future-proof if
we end up doing the linked list approach.

> --
> With Best Regards,
> Andy Shevchenko
>
>
>

Bart