Re: [PATCH v2 07/17] drm/tests: helpers: Make sure the device is bound

[Maíra Canal]

On 11/28/22 11:53, Maxime Ripard wrote:
> The device managed resources are freed when the device is detached, so
> it has to be bound in the first place.
> 
> Let's create a fake driver that we will bind to our fake device to
> benefit from the device managed cleanups in our tests.
> 
> Signed-off-by: Maxime Ripard <maxime@xxxxxxxxxx>

Reviewed-by: Maíra Canal <mcanal@xxxxxxxxxx>

Best Regards,
- Maíra Canal

> ---
>  drivers/gpu/drm/tests/drm_kunit_helpers.c | 26 +++++++++++++++++++++++++-
>  1 file changed, 25 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/tests/drm_kunit_helpers.c b/drivers/gpu/drm/tests/drm_kunit_helpers.c
> index 15678ab823b0..5d3e29353d1a 100644
> --- a/drivers/gpu/drm/tests/drm_kunit_helpers.c
> +++ b/drivers/gpu/drm/tests/drm_kunit_helpers.c
> @@ -18,12 +18,32 @@ struct kunit_dev {
>  static const struct drm_mode_config_funcs drm_mode_config_funcs = {
>  };
>  
> +static int fake_probe(struct platform_device *pdev)
> +{
> +	return 0;
> +}
> +
> +static int fake_remove(struct platform_device *pdev)
> +{
> +	return 0;
> +}
> +
> +static struct platform_driver fake_platform_driver = {
> +	.probe	= fake_probe,
> +	.remove	= fake_remove,
> +	.driver = {
> +		.name	= KUNIT_DEVICE_NAME,
> +	},
> +};
> +
>  /**
>   * drm_kunit_helper_alloc_device - Allocate a mock device for a KUnit test
>   * @test: The test context object
>   *
>   * This allocates a fake struct &device to create a mock for a Kunit
> - * test.
> + * test. The device will also be bound to a fake driver. It will thus be
> + * able to leverage the usual infrastructure and most notably the
> + * device-managed resources just like a "real" device.
>   *
>   * Callers need to make sure drm_kunit_helper_free_device() on the
>   * device when done.
> @@ -36,6 +56,9 @@ struct device *drm_kunit_helper_alloc_device(struct kunit *test)
>  	struct platform_device *pdev;
>  	int ret;
>  
> +	ret = platform_driver_register(&fake_platform_driver);
> +	KUNIT_ASSERT_EQ(test, ret, 0);
> +
>  	pdev = platform_device_alloc(KUNIT_DEVICE_NAME, PLATFORM_DEVID_NONE);
>  	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, pdev);
>  
> @@ -58,6 +81,7 @@ void drm_kunit_helper_free_device(struct kunit *test, struct device *dev)
>  	struct platform_device *pdev = to_platform_device(dev);
>  
>  	platform_device_unregister(pdev);
> +	platform_driver_unregister(&fake_platform_driver);
>  }
>  EXPORT_SYMBOL(drm_kunit_helper_free_device);
>  
>