// 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/err.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 boolkunit_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); /** * kunit_platform_device_register_full() - Register a KUnit test-managed platform *                                         device described by platform device info * @test: test context * @pdevinfo: platform device information describing the new device * * Register a test-managed platform device. The device is unregistered when the * test completes. * * Return: New platform device on success, IS_ERR() on error. */struct platform_device *kunit_platform_device_register_full(struct kunit *test,				    const struct platform_device_info *pdevinfo){	struct platform_device *pdev;	int ret; 	pdev = platform_device_register_full(pdevinfo);	if (IS_ERR(pdev))		return pdev; 	ret = kunit_add_action_or_reset(test, platform_device_unregister_wrapper, pdev);	if (ret)		return ERR_PTR(ret); 	return pdev;}EXPORT_SYMBOL_GPL(kunit_platform_device_register_full); static boolkunit_platform_device_add_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_add_exit;} /** * kunit_platform_device_unregister() - Unregister a KUnit-managed platform device * @test: test context * @pdev: platform device to unregister * * Unregister a test-managed platform device and cancel its release action. */void kunit_platform_device_unregister(struct kunit *test,				      struct platform_device *pdev){	struct kunit_resource *res; 	res = kunit_find_resource(test, kunit_platform_device_add_match, pdev);	if (res) {		res->free = NULL;		kunit_put_resource(res);	} else {		kunit_remove_action(test, platform_device_unregister_wrapper, pdev);	} 	platform_device_unregister(pdev);}EXPORT_SYMBOL_GPL(kunit_platform_device_unregister); 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);