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 

Reviewed-by: Maíra Canal 

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  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(_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(_platform_driver);
>  }
>  EXPORT_SYMBOL(drm_kunit_helper_free_device);
>  
> 

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

[Maxime Ripard]

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 
---
 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  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(_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(_platform_driver);
 }
 EXPORT_SYMBOL(drm_kunit_helper_free_device);
 

-- 
2.38.1-b4-0.11.0-dev-d416f