Re: [PATCH 5/5] gpio: kunit: add test cases verifying swnode devlink support

[Andy Shevchenko <andriy.shevchenko@linux.intel.com>]

On Mon, Jun 29, 2026 at 12:52:10PM +0200, Bartosz Golaszewski wrote:
> The software node fw_devlink support already has its own kunit suite, but
> that verifies the fwnode links in isolation. Add GPIO tests that prove
> the ordering works in a real-life use-case: a GPIO consumer that
> references its provider via a software node.
> 
> The first suite registers the provider's software node, adds the consumer
> device first and checks that fw_devlink defers its probe until the
> provider has been added and bound. The second covers the fallback:
> with the provider's software node not yet registered no supplier link is
> created, so the consumer probes, devm_gpiod_get() returns -EPROBE_DEFER
> and the consumer only binds once the provider shows up.
> 
> While at it: the existing gpio_unbind_with_consumers() test keeps the
> consumer bound while the provider goes away and then operates the orphaned
> descriptor. With software nodes now being covered by fw_devlink that would
> instead force-unbind the consumer along with the provider, so opt it out
> by setting FWNODE_FLAG_LINKS_ADDED.

...

+ cleanup.h // guard()()
+ err.h // IS_ERR()

>  #include <linux/platform_device.h>
>  #include <linux/property.h>

+ types.h // bool

> +#include <kunit/fwnode.h>
>  #include <kunit/platform_device.h>
>  #include <kunit/test.h>

...

> +	properties[1] = (struct property_entry){ };

Just zero the whole array at the definition time.

...

> +	pdevinfo = (struct platform_device_info){

It's better to have a space after ).

> +		.name = GPIO_PROBE_ORDER_TEST_CONSUMER,
> +		.id = PLATFORM_DEVID_NONE,
> +		.data = &gpio_probe_order_pdata_template,
> +		.size_data = sizeof(gpio_probe_order_pdata_template),
> +		.properties = properties,
> +	};

...

> +	pdevinfo = (struct platform_device_info){

Ditto.

> +		.name = GPIO_TEST_PROVIDER,
> +		.id = PLATFORM_DEVID_NONE,
> +		.swnode = &gpio_test_provider_swnode,
> +	};

...

> +struct gpio_probe_defer_pdata {
> +	int probe_count;

Why is this signed?

> +	int gpio_err;
> +};

...

> +static int gpio_probe_defer_consumer_probe(struct platform_device *pdev)
> +{
> +	struct device *dev = &pdev->dev;
> +	struct gpio_probe_defer_pdata *pdata = dev_get_platdata(dev);
> +	struct gpio_desc *desc;

> +	pdata->probe_count++;

Even in case of error?

> +	desc = devm_gpiod_get(dev, "foo", GPIOD_OUT_HIGH);
> +	if (IS_ERR(desc)) {
> +		pdata->gpio_err = PTR_ERR(desc);
> +		return pdata->gpio_err;
> +	}
> +
> +	pdata->gpio_err = 0;
> +
> +	return 0;
> +}

...

> +static void gpio_swnode_probe_defer_on_unregistered(struct kunit *test)

As per above.

-- 
With Best Regards,
Andy Shevchenko