Re: [PATCH v4 2/2] gpio: swnode: defer probe on references to unregistered software nodes

[Andy Shevchenko]

On Tue, Apr 07, 2026 at 03:27:58PM +0200, Bartosz Golaszewski wrote:
> fwnode_property_get_reference_args() now returns -ENOTCONN when called
> on a software node referencing another software node which has not yet
> been registered as a firmware node. It makes sense to defer probe in this
> situation as the node will most likely be registered later on and we'll
> be able to resolve the reference eventually. Change the behavior of
> swnode_find_gpio() to return -EPROBE_DEFER if the software node reference
> resolution returns -ENOTCONN.

Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>

...

>  		ret = swnode_gpio_get_reference(fwnode, propname, idx, &args);

>  		if (ret == 0)
>  			break;

Maybe check for an error first? Dunno. Up to you.

		if (ret == -ENOTCONN)
			...
		if (ret)
			continue;

		/* The reference is found, bail out */
		break;

(Also may be done in a separate change no need to mix these things
 in the proposed change.)

> +		if (ret == -ENOTCONN)
> +			/*
> +			 * -ENOTCONN for a software node reference lookup means
> +			 *  that a remote struct software_node exists but has
> +			 *  not yet been registered as a firmware node. Defer
> +			 *  until this happens.
> +			 */
> +			return ERR_PTR(-EPROBE_DEFER);

-- 
With Best Regards,
Andy Shevchenko