lib/kunit/platform.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0
 /*
  * Test managed platform driver
  */

 #include <linux/completion.h>
 #include <linux/device/bus.h>
 #include <linux/device/driver.h>
 #include <linux/platform_device.h>

 #include <kunit/platform_device.h>
 #include <kunit/resource.h>

 struct kunit_platform_device_alloc_params {
 	const char *name;
 	int id;
 };

 static int kunit_platform_device_alloc_init(struct kunit_resource *res, void *context)
 {
 	struct kunit_platform_device_alloc_params *params = context;
 	struct platform_device *pdev;

 	pdev = platform_device_alloc(params->name, params->id);
 	if (!pdev)
 		return -ENOMEM;

 	res->data = pdev;

 	return 0;
 }

 static void kunit_platform_device_alloc_exit(struct kunit_resource *res)
 {
 	struct platform_device *pdev = res->data;

 	platform_device_put(pdev);
 }

 /**
  * kunit_platform_device_alloc() - Allocate a KUnit test managed platform device
  * @test: test context
  * @name: device name of platform device to alloc
  * @id: identifier of platform device to alloc.
  *
  * Allocate a test managed platform device. The device is put when the test completes.
  *
  * Return: Allocated platform device on success, NULL on failure.
  */
 struct platform_device *
 kunit_platform_device_alloc(struct kunit *test, const char *name, int id)
 {
 	struct kunit_platform_device_alloc_params params = {
 		.name = name,
 		.id = id,
 	};

 	return kunit_alloc_resource(test,
 				    kunit_platform_device_alloc_init,
 				    kunit_platform_device_alloc_exit,
 				    GFP_KERNEL, &params);
 }
 EXPORT_SYMBOL_GPL(kunit_platform_device_alloc);

 static void kunit_platform_device_add_exit(struct kunit_resource *res)
 {
 	struct platform_device *pdev = res->data;

 	platform_device_unregister(pdev);
 }

 static bool
 kunit_platform_device_alloc_match(struct kunit *test,
 				  struct kunit_resource *res, void *match_data)
 {
 	struct platform_device *pdev = match_data;

 	return res->data == pdev && res->free == kunit_platform_device_alloc_exit;
 }

 KUNIT_DEFINE_ACTION_WRAPPER(platform_device_unregister_wrapper,
 			    platform_device_unregister, struct platform_device *);
 /**
  * kunit_platform_device_add() - Register a KUnit test managed platform device
  * @test: test context
  * @pdev: platform device to add
  *
  * Register a test managed platform device. The device is unregistered when the
  * test completes.
  *
  * Return: 0 on success, negative errno on failure.
  */
 int kunit_platform_device_add(struct kunit *test, struct platform_device *pdev)
 {
 	struct kunit_resource *res;
 	int ret;

 	ret = platform_device_add(pdev);
 	if (ret)
 		return ret;

 	res = kunit_find_resource(test, kunit_platform_device_alloc_match, pdev);
 	if (res) {
 		/*
 		 * Transfer the reference count of the platform device if it
 		 * was allocated with kunit_platform_device_alloc(). In this
 		 * case, calling platform_device_put() when the test exits from
 		 * kunit_platform_device_alloc_exit() would lead to reference
 		 * count underflow because platform_device_unregister_wrapper()
 		 * calls platform_device_unregister() which also calls
 		 * platform_device_put().
 		 *
 		 * Usually callers transfer the refcount initialized in
 		 * platform_device_alloc() to platform_device_add() by calling
 		 * platform_device_unregister() when platform_device_add()
 		 * succeeds or platform_device_put() when it fails. KUnit has to
 		 * keep this straight by redirecting the free routine for the
 		 * resource to the right function. Luckily this only has to
 		 * account for the success scenario.
 		 */
 		res->free = kunit_platform_device_add_exit;
 		kunit_put_resource(res);
 	} else {
 		ret = kunit_add_action_or_reset(test, platform_device_unregister_wrapper, pdev);
 		if (ret)
 			return ret;
 	}

 	return 0;
 }
 EXPORT_SYMBOL_GPL(kunit_platform_device_add);

 struct kunit_platform_device_probe_nb {
 	struct completion *x;
 	struct device *dev;
 	struct notifier_block nb;
 };

 static int kunit_platform_device_probe_notify(struct notifier_block *nb,
 					      unsigned long event, void *data)
 {
 	struct kunit_platform_device_probe_nb *knb;
 	struct device *dev = data;

 	knb = container_of(nb, struct kunit_platform_device_probe_nb, nb);
 	if (event != BUS_NOTIFY_BOUND_DRIVER || knb->dev != dev)
 		return NOTIFY_DONE;

 	complete(knb->x);

 	return NOTIFY_OK;
 }

 static void kunit_platform_device_probe_nb_remove(void *nb)
 {
 	bus_unregister_notifier(&platform_bus_type, nb);
 }

 /**
  * kunit_platform_device_prepare_wait_for_probe() - Prepare a completion
  * variable to wait for a platform device to probe
  * @test: test context
  * @pdev: platform device to prepare to wait for probe of
  * @x: completion variable completed when @dev has probed
  *
  * Prepare a completion variable @x to wait for @pdev to probe. Waiting on the
  * completion forces a preemption, allowing the platform driver to probe.
  *
  * Example
  *
  * .. code-block:: c
  *
  *	static int kunit_platform_driver_probe(struct platform_device *pdev)
  *	{
  *		return 0;
  *	}
  *
  *	static void kunit_platform_driver_test(struct kunit *test)
  *	{
  *		struct platform_device *pdev;
  *		struct platform_driver *pdrv;
  *		DECLARE_COMPLETION_ONSTACK(comp);
  *
  *		pdev = kunit_platform_device_alloc(test, "kunit-platform", -1);
  *		KUNIT_ASSERT_NOT_ERR_OR_NULL(test, pdev);
  *		KUNIT_ASSERT_EQ(test, 0, kunit_platform_device_add(test, pdev));
  *
  *		pdrv = kunit_kzalloc(test, sizeof(*pdrv), GFP_KERNEL);
  *		KUNIT_ASSERT_NOT_ERR_OR_NULL(test, pdrv);
  *
  *		pdrv->probe = kunit_platform_driver_probe;
  *		pdrv->driver.name = "kunit-platform";
  *		pdrv->driver.owner = THIS_MODULE;
  *
  *		KUNIT_ASSERT_EQ(test, 0, kunit_platform_device_prepare_wait_for_probe(test, pdev, &comp));
  *		KUNIT_ASSERT_EQ(test, 0, kunit_platform_driver_register(test, pdrv));
  *
  *		KUNIT_EXPECT_NE(test, 0, wait_for_completion_timeout(&comp, 3 * HZ));
  *	}
  *
  * Return: 0 on success, negative errno on failure.
  */
 int kunit_platform_device_prepare_wait_for_probe(struct kunit *test,
 						 struct platform_device *pdev,
 						 struct completion *x)
 {
 	struct device *dev = &pdev->dev;
 	struct kunit_platform_device_probe_nb *knb;
 	bool bound;

 	knb = kunit_kzalloc(test, sizeof(*knb), GFP_KERNEL);
 	if (!knb)
 		return -ENOMEM;

 	knb->nb.notifier_call = kunit_platform_device_probe_notify;
 	knb->dev = dev;
 	knb->x = x;

 	device_lock(dev);
 	bound = device_is_bound(dev);
 	if (bound) {
 		device_unlock(dev);
 		complete(x);
 		kunit_kfree(test, knb);
 		return 0;
 	}

 	bus_register_notifier(&platform_bus_type, &knb->nb);
 	device_unlock(&pdev->dev);

 	return kunit_add_action_or_reset(test, kunit_platform_device_probe_nb_remove, &knb->nb);
 }
 EXPORT_SYMBOL_GPL(kunit_platform_device_prepare_wait_for_probe);

 KUNIT_DEFINE_ACTION_WRAPPER(platform_driver_unregister_wrapper,
 			    platform_driver_unregister, struct platform_driver *);
 /**
  * kunit_platform_driver_register() - Register a KUnit test managed platform driver
  * @test: test context
  * @drv: platform driver to register
  *
  * Register a test managed platform driver. This allows callers to embed the
  * @drv in a container structure and use container_of() in the probe function
  * to pass information to KUnit tests.
  *
  * Example
  *
  * .. code-block:: c
  *
  *	struct kunit_test_context {
  *		struct platform_driver pdrv;
  *		const char *data;
  *	};
  *
  *	static inline struct kunit_test_context *
  *	to_test_context(struct platform_device *pdev)
  *	{
  *		return container_of(to_platform_driver(pdev->dev.driver),
  *				    struct kunit_test_context,
  *				    pdrv);
  *	}
  *
  *	static int kunit_platform_driver_probe(struct platform_device *pdev)
  *	{
  *		struct kunit_test_context *ctx;
  *
  *		ctx = to_test_context(pdev);
  *		ctx->data = "test data";
  *
  *		return 0;
  *	}
  *
  *	static void kunit_platform_driver_test(struct kunit *test)
  *	{
  *		struct kunit_test_context *ctx;
  *
  *		ctx = kunit_kzalloc(test, sizeof(*ctx), GFP_KERNEL);
  *		KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
  *
  *		ctx->pdrv.probe = kunit_platform_driver_probe;
  *		ctx->pdrv.driver.name = "kunit-platform";
  *		ctx->pdrv.driver.owner = THIS_MODULE;
  *
  *		KUNIT_EXPECT_EQ(test, 0, kunit_platform_driver_register(test, &ctx->pdrv));
  *		<... wait for driver to probe ...>
  *		KUNIT_EXPECT_STREQ(test, ctx->data, "test data");
  *	}
  *
  * Return: 0 on success, negative errno on failure.
  */
 int kunit_platform_driver_register(struct kunit *test,
 				   struct platform_driver *drv)
 {
 	int ret;

 	ret = platform_driver_register(drv);
 	if (ret)
 		return ret;

 	return kunit_add_action_or_reset(test, platform_driver_unregister_wrapper, drv);
 }
 EXPORT_SYMBOL_GPL(kunit_platform_driver_register);
	// SPDX-License-Identifier: GPL-2.0
	/*
	* Test managed platform driver
	*/

	#include <linux/completion.h>
	#include <linux/device/bus.h>
	#include <linux/device/driver.h>
	#include <linux/platform_device.h>

	#include <kunit/platform_device.h>
	#include <kunit/resource.h>

	struct kunit_platform_device_alloc_params {
	const char *name;
	int id;
	};

	static int kunit_platform_device_alloc_init(struct kunit_resource res, void context)
	{
	struct kunit_platform_device_alloc_params *params = context;
	struct platform_device *pdev;

	pdev = platform_device_alloc(params->name, params->id);
	if (!pdev)
	return -ENOMEM;

	res->data = pdev;

	return 0;
	}

	static void kunit_platform_device_alloc_exit(struct kunit_resource *res)
	{
	struct platform_device *pdev = res->data;

	platform_device_put(pdev);
	}

	/**
	* kunit_platform_device_alloc() - Allocate a KUnit test managed platform device
	* @test: test context
	* @name: device name of platform device to alloc
	* @id: identifier of platform device to alloc.
	*
	* Allocate a test managed platform device. The device is put when the test completes.
	*
	* Return: Allocated platform device on success, NULL on failure.
	*/
	struct platform_device *
	kunit_platform_device_alloc(struct kunit test, const char name, int id)
	{
	struct kunit_platform_device_alloc_params params = {
	.name = name,
	.id = id,
	};

	return kunit_alloc_resource(test,
	kunit_platform_device_alloc_init,
	kunit_platform_device_alloc_exit,
	GFP_KERNEL, &params);
	}
	EXPORT_SYMBOL_GPL(kunit_platform_device_alloc);

	static void kunit_platform_device_add_exit(struct kunit_resource *res)
	{
	struct platform_device *pdev = res->data;

	platform_device_unregister(pdev);
	}

	static bool
	kunit_platform_device_alloc_match(struct kunit *test,
	struct kunit_resource res, void match_data)
	{
	struct platform_device *pdev = match_data;

	return res->data == pdev && res->free == kunit_platform_device_alloc_exit;
	}

	KUNIT_DEFINE_ACTION_WRAPPER(platform_device_unregister_wrapper,
	platform_device_unregister, struct platform_device *);
	/**
	* kunit_platform_device_add() - Register a KUnit test managed platform device
	* @test: test context
	* @pdev: platform device to add
	*
	* Register a test managed platform device. The device is unregistered when the
	* test completes.
	*
	* Return: 0 on success, negative errno on failure.
	*/
	int kunit_platform_device_add(struct kunit test, struct platform_device pdev)
	{
	struct kunit_resource *res;
	int ret;

	ret = platform_device_add(pdev);
	if (ret)
	return ret;

	res = kunit_find_resource(test, kunit_platform_device_alloc_match, pdev);
	if (res) {
	/*
	* Transfer the reference count of the platform device if it
	* was allocated with kunit_platform_device_alloc(). In this
	* case, calling platform_device_put() when the test exits from
	* kunit_platform_device_alloc_exit() would lead to reference
	* count underflow because platform_device_unregister_wrapper()
	* calls platform_device_unregister() which also calls
	* platform_device_put().
	*
	* Usually callers transfer the refcount initialized in
	* platform_device_alloc() to platform_device_add() by calling
	* platform_device_unregister() when platform_device_add()
	* succeeds or platform_device_put() when it fails. KUnit has to
	* keep this straight by redirecting the free routine for the
	* resource to the right function. Luckily this only has to
	* account for the success scenario.
	*/
	res->free = kunit_platform_device_add_exit;
	kunit_put_resource(res);
	} else {
	ret = kunit_add_action_or_reset(test, platform_device_unregister_wrapper, pdev);
	if (ret)
	return ret;
	}

	return 0;
	}
	EXPORT_SYMBOL_GPL(kunit_platform_device_add);

	struct kunit_platform_device_probe_nb {
	struct completion *x;
	struct device *dev;
	struct notifier_block nb;
	};

	static int kunit_platform_device_probe_notify(struct notifier_block *nb,
	unsigned long event, void *data)
	{
	struct kunit_platform_device_probe_nb *knb;
	struct device *dev = data;

	knb = container_of(nb, struct kunit_platform_device_probe_nb, nb);
	if (event != BUS_NOTIFY_BOUND_DRIVER \|\| knb->dev != dev)
	return NOTIFY_DONE;

	complete(knb->x);

	return NOTIFY_OK;
	}

	static void kunit_platform_device_probe_nb_remove(void *nb)
	{
	bus_unregister_notifier(&platform_bus_type, nb);
	}

	/**
	* kunit_platform_device_prepare_wait_for_probe() - Prepare a completion
	* variable to wait for a platform device to probe
	* @test: test context
	* @pdev: platform device to prepare to wait for probe of
	* @x: completion variable completed when @dev has probed
	*
	* Prepare a completion variable @x to wait for @pdev to probe. Waiting on the
	* completion forces a preemption, allowing the platform driver to probe.
	*
	* Example
	*
	* .. code-block:: c
	*
	* static int kunit_platform_driver_probe(struct platform_device *pdev)
	* {
	* return 0;
	* }
	*
	* static void kunit_platform_driver_test(struct kunit *test)
	* {
	* struct platform_device *pdev;
	* struct platform_driver *pdrv;
	* DECLARE_COMPLETION_ONSTACK(comp);
	*
	* pdev = kunit_platform_device_alloc(test, "kunit-platform", -1);
	* KUNIT_ASSERT_NOT_ERR_OR_NULL(test, pdev);
	* KUNIT_ASSERT_EQ(test, 0, kunit_platform_device_add(test, pdev));
	*
	* pdrv = kunit_kzalloc(test, sizeof(*pdrv), GFP_KERNEL);
	* KUNIT_ASSERT_NOT_ERR_OR_NULL(test, pdrv);
	*
	* pdrv->probe = kunit_platform_driver_probe;
	* pdrv->driver.name = "kunit-platform";
	* pdrv->driver.owner = THIS_MODULE;
	*
	* KUNIT_ASSERT_EQ(test, 0, kunit_platform_device_prepare_wait_for_probe(test, pdev, &comp));
	* KUNIT_ASSERT_EQ(test, 0, kunit_platform_driver_register(test, pdrv));
	*
	* KUNIT_EXPECT_NE(test, 0, wait_for_completion_timeout(&comp, 3 * HZ));
	* }
	*
	* Return: 0 on success, negative errno on failure.
	*/
	int kunit_platform_device_prepare_wait_for_probe(struct kunit *test,
	struct platform_device *pdev,
	struct completion *x)
	{
	struct device *dev = &pdev->dev;
	struct kunit_platform_device_probe_nb *knb;
	bool bound;

	knb = kunit_kzalloc(test, sizeof(*knb), GFP_KERNEL);
	if (!knb)
	return -ENOMEM;

	knb->nb.notifier_call = kunit_platform_device_probe_notify;
	knb->dev = dev;
	knb->x = x;

	device_lock(dev);
	bound = device_is_bound(dev);
	if (bound) {
	device_unlock(dev);
	complete(x);
	kunit_kfree(test, knb);
	return 0;
	}

	bus_register_notifier(&platform_bus_type, &knb->nb);
	device_unlock(&pdev->dev);

	return kunit_add_action_or_reset(test, kunit_platform_device_probe_nb_remove, &knb->nb);
	}
	EXPORT_SYMBOL_GPL(kunit_platform_device_prepare_wait_for_probe);

	KUNIT_DEFINE_ACTION_WRAPPER(platform_driver_unregister_wrapper,
	platform_driver_unregister, struct platform_driver *);
	/**
	* kunit_platform_driver_register() - Register a KUnit test managed platform driver
	* @test: test context
	* @drv: platform driver to register
	*
	* Register a test managed platform driver. This allows callers to embed the
	* @drv in a container structure and use container_of() in the probe function
	* to pass information to KUnit tests.
	*
	* Example
	*
	* .. code-block:: c
	*
	* struct kunit_test_context {
	* struct platform_driver pdrv;
	* const char *data;
	* };
	*
	* static inline struct kunit_test_context *
	* to_test_context(struct platform_device *pdev)
	* {
	* return container_of(to_platform_driver(pdev->dev.driver),
	* struct kunit_test_context,
	* pdrv);
	* }
	*
	* static int kunit_platform_driver_probe(struct platform_device *pdev)
	* {
	* struct kunit_test_context *ctx;
	*
	* ctx = to_test_context(pdev);
	* ctx->data = "test data";
	*
	* return 0;
	* }
	*
	* static void kunit_platform_driver_test(struct kunit *test)
	* {
	* struct kunit_test_context *ctx;
	*
	* ctx = kunit_kzalloc(test, sizeof(*ctx), GFP_KERNEL);
	* KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
	*
	* ctx->pdrv.probe = kunit_platform_driver_probe;
	* ctx->pdrv.driver.name = "kunit-platform";
	* ctx->pdrv.driver.owner = THIS_MODULE;
	*
	* KUNIT_EXPECT_EQ(test, 0, kunit_platform_driver_register(test, &ctx->pdrv));
	* <... wait for driver to probe ...>
	* KUNIT_EXPECT_STREQ(test, ctx->data, "test data");
	* }
	*
	* Return: 0 on success, negative errno on failure.
	*/
	int kunit_platform_driver_register(struct kunit *test,
	struct platform_driver *drv)
	{
	int ret;

	ret = platform_driver_register(drv);
	if (ret)
	return ret;

	return kunit_add_action_or_reset(test, platform_driver_unregister_wrapper, drv);
	}
	EXPORT_SYMBOL_GPL(kunit_platform_driver_register);