Introduce KUnit resource wrappers around platform_driver_register(), platform_device_alloc(), and platform_device_add() so that test authors can register platform drivers/devices from their tests and have the drivers/devices automatically be unregistered when the test is done.
This makes test setup code simpler when a platform driver or platform device is needed. Add a few test cases at the same time to make sure the APIs work as intended.
Cc: Brendan Higgins brendan.higgins@linux.dev Cc: David Gow davidgow@google.com Cc: Rae Moar rmoar@google.com Cc: Greg Kroah-Hartman gregkh@linuxfoundation.org Cc: "Rafael J. Wysocki" rafael@kernel.org Signed-off-by: Stephen Boyd sboyd@kernel.org --- Documentation/dev-tools/kunit/api/index.rst | 5 + .../dev-tools/kunit/api/platformdevice.rst | 10 + include/kunit/platform_device.h | 20 ++ lib/kunit/Makefile | 4 +- lib/kunit/platform-test.c | 223 +++++++++++++ lib/kunit/platform.c | 302 ++++++++++++++++++ 6 files changed, 563 insertions(+), 1 deletion(-) create mode 100644 Documentation/dev-tools/kunit/api/platformdevice.rst create mode 100644 include/kunit/platform_device.h create mode 100644 lib/kunit/platform-test.c create mode 100644 lib/kunit/platform.c
diff --git a/Documentation/dev-tools/kunit/api/index.rst b/Documentation/dev-tools/kunit/api/index.rst index 282befa17edf..02b26f5e8750 100644 --- a/Documentation/dev-tools/kunit/api/index.rst +++ b/Documentation/dev-tools/kunit/api/index.rst @@ -10,6 +10,7 @@ API Reference resource functionredirection of + platformdevice
This page documents the KUnit kernel testing API. It is divided into the @@ -36,3 +37,7 @@ Driver KUnit API Documentation/dev-tools/kunit/api/of.rst
- Documents the KUnit device tree (OF) API + +Documentation/dev-tools/kunit/api/platformdevice.rst + + - Documents the KUnit platform device API diff --git a/Documentation/dev-tools/kunit/api/platformdevice.rst b/Documentation/dev-tools/kunit/api/platformdevice.rst new file mode 100644 index 000000000000..49ddd5729003 --- /dev/null +++ b/Documentation/dev-tools/kunit/api/platformdevice.rst @@ -0,0 +1,10 @@ +.. SPDX-License-Identifier: GPL-2.0 + +=================== +Platform Device API +=================== + +The KUnit platform device API is used to test platform devices. + +.. kernel-doc:: lib/kunit/platform.c + :export: diff --git a/include/kunit/platform_device.h b/include/kunit/platform_device.h new file mode 100644 index 000000000000..0fc0999d2420 --- /dev/null +++ b/include/kunit/platform_device.h @@ -0,0 +1,20 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _KUNIT_PLATFORM_DRIVER_H +#define _KUNIT_PLATFORM_DRIVER_H + +struct kunit; +struct platform_device; +struct platform_driver; + +struct platform_device * +kunit_platform_device_alloc(struct kunit *test, const char *name, int id); +int kunit_platform_device_add(struct kunit *test, struct platform_device *pdev); + +int kunit_platform_device_prepare_wait_for_probe(struct kunit *test, + struct platform_device *pdev, + struct completion *x); + +int kunit_platform_driver_register(struct kunit *test, + struct platform_driver *drv); + +#endif diff --git a/lib/kunit/Makefile b/lib/kunit/Makefile index 309659a32a78..a980ae62eff6 100644 --- a/lib/kunit/Makefile +++ b/lib/kunit/Makefile @@ -8,7 +8,8 @@ kunit-objs += test.o \ try-catch.o \ executor.o \ attributes.o \ - device.o + device.o \ + platform.o
ifeq ($(CONFIG_KUNIT_DEBUGFS),y) kunit-objs += debugfs.o @@ -18,6 +19,7 @@ endif obj-y += hooks.o
obj-$(CONFIG_KUNIT_TEST) += kunit-test.o +obj-$(CONFIG_KUNIT_TEST) += platform-test.o
# string-stream-test compiles built-in only. ifeq ($(CONFIG_KUNIT_TEST),y) diff --git a/lib/kunit/platform-test.c b/lib/kunit/platform-test.c new file mode 100644 index 000000000000..b4fbedadc55e --- /dev/null +++ b/lib/kunit/platform-test.c @@ -0,0 +1,223 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * KUnit test for platform driver infrastructure. + */ + +#include <linux/platform_device.h> + +#include <kunit/platform_device.h> +#include <kunit/test.h> + +/* + * Test that kunit_platform_device_alloc() creates a platform device. + */ +static void kunit_platform_device_alloc_test(struct kunit *test) +{ + KUNIT_EXPECT_NOT_ERR_OR_NULL(test, + kunit_platform_device_alloc(test, "kunit-platform", 1)); +} + +/* + * Test that kunit_platform_device_add() registers a platform device on the + * platform bus with the proper name and id. + */ +static void kunit_platform_device_add_test(struct kunit *test) +{ + struct platform_device *pdev; + const char *name = "kunit-platform-add"; + const int id = -1; + + pdev = kunit_platform_device_alloc(test, name, id); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, pdev); + + KUNIT_EXPECT_EQ(test, 0, kunit_platform_device_add(test, pdev)); + KUNIT_EXPECT_TRUE(test, dev_is_platform(&pdev->dev)); + KUNIT_EXPECT_STREQ(test, pdev->name, name); + KUNIT_EXPECT_EQ(test, pdev->id, id); +} + +/* + * Test that kunit_platform_device_add() called twice with the same device name + * and id fails the second time and properly cleans up. + */ +static void kunit_platform_device_add_twice_fails_test(struct kunit *test) +{ + struct platform_device *pdev; + const char *name = "kunit-platform-add-2"; + const int id = -1; + + pdev = kunit_platform_device_alloc(test, name, id); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, pdev); + KUNIT_ASSERT_EQ(test, 0, kunit_platform_device_add(test, pdev)); + + pdev = kunit_platform_device_alloc(test, name, id); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, pdev); + + KUNIT_EXPECT_NE(test, 0, kunit_platform_device_add(test, pdev)); +} + +static int kunit_platform_device_find_by_name(struct device *dev, const void *data) +{ + return strcmp(dev_name(dev), data) == 0; +} + +/* + * Test that kunit_platform_device_add() cleans up by removing the platform + * device when the test finishes. */ +static void kunit_platform_device_add_cleans_up(struct kunit *test) +{ + struct platform_device *pdev; + const char *name = "kunit-platform-clean"; + const int id = -1; + struct kunit fake; + struct device *dev; + + kunit_init_test(&fake, "kunit_platform_device_add_fake_test", NULL); + KUNIT_ASSERT_EQ(test, fake.status, KUNIT_SUCCESS); + + pdev = kunit_platform_device_alloc(&fake, name, id); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, pdev); + KUNIT_ASSERT_EQ(test, 0, kunit_platform_device_add(&fake, pdev)); + dev = bus_find_device(&platform_bus_type, NULL, name, + kunit_platform_device_find_by_name); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, dev); + put_device(dev); + + /* Remove pdev */ + kunit_cleanup(&fake); + + /* + * Failing to migrate the kunit_resource would lead to an extra + * put_device() call on the platform device. The best we can do here is + * make sure the device no longer exists on the bus, but if something + * is wrong we'll see a refcount underflow here. We can't test for a + * refcount underflow because the kref matches the lifetime of the + * device which should already be freed and could be used by something + * else. + */ + dev = bus_find_device(&platform_bus_type, NULL, name, + kunit_platform_device_find_by_name); + KUNIT_EXPECT_PTR_EQ(test, NULL, dev); + put_device(dev); +} + +/* + * Test suite for struct platform_device kunit APIs + */ +static struct kunit_case kunit_platform_device_test_cases[] = { + KUNIT_CASE(kunit_platform_device_alloc_test), + KUNIT_CASE(kunit_platform_device_add_test), + KUNIT_CASE(kunit_platform_device_add_twice_fails_test), + KUNIT_CASE(kunit_platform_device_add_cleans_up), + {} +}; + +static struct kunit_suite kunit_platform_device_suite = { + .name = "kunit_platform_device", + .test_cases = kunit_platform_device_test_cases, +}; + +struct kunit_platform_driver_test_context { + struct platform_driver pdrv; + const char *data; +}; + +static const char * const test_data = "test data"; + +static inline struct kunit_platform_driver_test_context * +to_test_context(struct platform_device *pdev) +{ + return container_of(to_platform_driver(pdev->dev.driver), + struct kunit_platform_driver_test_context, + pdrv); +} + +static int kunit_platform_driver_probe(struct platform_device *pdev) +{ + struct kunit_platform_driver_test_context *ctx; + + ctx = to_test_context(pdev); + ctx->data = test_data; + + return 0; +} + +/* Test that kunit_platform_driver_register() registers a driver that probes. */ +static void kunit_platform_driver_register_test(struct kunit *test) +{ + struct platform_device *pdev; + struct kunit_platform_driver_test_context *ctx; + DECLARE_COMPLETION_ONSTACK(comp); + const char *name = "kunit-platform-register"; + + ctx = kunit_kzalloc(test, sizeof(*ctx), GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx); + + pdev = kunit_platform_device_alloc(test, name, -1); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, pdev); + KUNIT_ASSERT_EQ(test, 0, kunit_platform_device_add(test, pdev)); + + ctx->pdrv.probe = kunit_platform_driver_probe; + ctx->pdrv.driver.name = name; + ctx->pdrv.driver.owner = THIS_MODULE; + + KUNIT_ASSERT_EQ(test, 0, kunit_platform_device_prepare_wait_for_probe(test, pdev, &comp)); + + KUNIT_EXPECT_EQ(test, 0, kunit_platform_driver_register(test, &ctx->pdrv)); + KUNIT_EXPECT_NE(test, 0, wait_for_completion_timeout(&comp, 3 * HZ)); + KUNIT_EXPECT_STREQ(test, ctx->data, test_data); +} + +/* + * Test that kunit_platform_device_prepare_wait_for_probe() completes the completion + * when the device is already probed. + */ +static void kunit_platform_device_prepare_wait_for_probe_completes_when_already_probed(struct kunit *test) +{ + struct platform_device *pdev; + struct kunit_platform_driver_test_context *ctx; + DECLARE_COMPLETION_ONSTACK(comp); + const char *name = "kunit-platform-wait"; + + ctx = kunit_kzalloc(test, sizeof(*ctx), GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx); + + pdev = kunit_platform_device_alloc(test, name, -1); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, pdev); + KUNIT_ASSERT_EQ(test, 0, kunit_platform_device_add(test, pdev)); + + ctx->pdrv.probe = kunit_platform_driver_probe; + ctx->pdrv.driver.name = name; + ctx->pdrv.driver.owner = THIS_MODULE; + + /* Make sure driver has actually probed */ + 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, &ctx->pdrv)); + KUNIT_ASSERT_NE(test, 0, wait_for_completion_timeout(&comp, 3 * HZ)); + + reinit_completion(&comp); + KUNIT_ASSERT_EQ(test, 0, kunit_platform_device_prepare_wait_for_probe(test, pdev, &comp)); + + KUNIT_EXPECT_NE(test, 0, wait_for_completion_timeout(&comp, HZ)); +} + +static struct kunit_case kunit_platform_driver_test_cases[] = { + KUNIT_CASE(kunit_platform_driver_register_test), + KUNIT_CASE(kunit_platform_device_prepare_wait_for_probe_completes_when_already_probed), + {} +}; + +/* + * Test suite for struct platform_driver kunit APIs + */ +static struct kunit_suite kunit_platform_driver_suite = { + .name = "kunit_platform_driver", + .test_cases = kunit_platform_driver_test_cases, +}; + +kunit_test_suites( + &kunit_platform_device_suite, + &kunit_platform_driver_suite, +); + +MODULE_LICENSE("GPL"); diff --git a/lib/kunit/platform.c b/lib/kunit/platform.c new file mode 100644 index 000000000000..ba1b0006dc45 --- /dev/null +++ b/lib/kunit/platform.c @@ -0,0 +1,302 @@ +// 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, ¶ms); +} +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);