Add a module containing kunit test cases for GPIO core. The idea is to use it to test functionalities that can't easily be tested from user-space with kernel selftests or GPIO character device test suites provided by the libgpiod package.
For now add test cases that verify software node based lookup and ensure that a GPIO provider unbinding with active consumers does not cause a crash. Signed-off-by: Bartosz Golaszewski <[email protected]> --- drivers/gpio/Kconfig | 8 + drivers/gpio/Makefile | 1 + drivers/gpio/gpiolib-kunit.c | 358 +++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 367 insertions(+) diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig index 00fcab5d09a4294ed778cea78af5867a0f6e481b..0306005fb7d65ae85905e967b9065fd74db753db 100644 --- a/drivers/gpio/Kconfig +++ b/drivers/gpio/Kconfig @@ -102,6 +102,14 @@ config GPIO_CDEV_V1 This ABI version is deprecated. Please use the latest ABI for new developments. +config GPIO_KUNIT + tristate "Build GPIO Kunit test cases" + depends on KUNIT + default KUNIT_ALL_TESTS + help + Say Y here to build the module containing Kunit test cases verifying + the functionality of the GPIO subsystem. + config GPIO_GENERIC depends on HAS_IOMEM # Only for IOMEM drivers tristate diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile index 2ea47d9d3dca948e1cdc46965e83b0e1b6de5f70..c66b6dd659b16b80b6bb6b15fac3e3f462dec596 100644 --- a/drivers/gpio/Makefile +++ b/drivers/gpio/Makefile @@ -13,6 +13,7 @@ obj-$(CONFIG_GPIO_ACPI) += gpiolib-acpi.o gpiolib-acpi-y := gpiolib-acpi-core.o gpiolib-acpi-quirks.o obj-$(CONFIG_GPIOLIB) += gpiolib-swnode.o obj-$(CONFIG_GPIO_SHARED) += gpiolib-shared.o +obj-$(CONFIG_GPIO_KUNIT) += gpiolib-kunit.o # Device drivers. Generally keep list sorted alphabetically obj-$(CONFIG_GPIO_REGMAP) += gpio-regmap.o diff --git a/drivers/gpio/gpiolib-kunit.c b/drivers/gpio/gpiolib-kunit.c new file mode 100644 index 0000000000000000000000000000000000000000..380b68f879e55433668353bb88067d561142a5bc --- /dev/null +++ b/drivers/gpio/gpiolib-kunit.c @@ -0,0 +1,358 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (C) Qualcomm Technologies, Inc. and/or its subsidiaries + */ + +#include <linux/fwnode.h> +#include <linux/gpio/consumer.h> +#include <linux/gpio/driver.h> +#include <linux/gpio/machine.h> +#include <linux/gpio/property.h> +#include <linux/notifier.h> +#include <linux/platform_device.h> +#include <linux/property.h> + +#include <kunit/platform_device.h> +#include <kunit/test.h> + +#define GPIO_TEST_PROVIDER "gpio-test-provider" +#define GPIO_SWNODE_TEST_CONSUMER "gpio-swnode-test-consumer" +#define GPIO_UNBIND_TEST_CONSUMER "gpio-unbind-test-consumer" + +static int gpio_test_provider_get_direction(struct gpio_chip *gc, unsigned int offset) +{ + return GPIO_LINE_DIRECTION_OUT; +} + +static int gpio_test_provider_set(struct gpio_chip *gc, unsigned int offset, int value) +{ + return 0; +} + +static int gpio_test_provider_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct gpio_chip *gc; + + gc = devm_kzalloc(dev, sizeof(*gc), GFP_KERNEL); + if (!gc) + return -ENOMEM; + + gc->base = -1; + gc->ngpio = 4; + gc->label = "gpio-swnode-consumer-test-device"; + gc->parent = dev; + gc->owner = THIS_MODULE; + + gc->get_direction = gpio_test_provider_get_direction; + gc->set = gpio_test_provider_set; + + return devm_gpiochip_add_data(dev, gc, NULL); +} + +static struct platform_driver gpio_test_provider_driver = { + .probe = gpio_test_provider_probe, + .driver = { + .name = GPIO_TEST_PROVIDER, + }, +}; + +static const struct software_node gpio_test_provider_swnode = { + .name = "gpio-test-provider-primary", +}; + +struct gpio_swnode_consumer_pdata { + bool gpio_ok; +}; + +static const struct gpio_swnode_consumer_pdata gpio_swnode_pdata_template = { + .gpio_ok = false, +}; + +static int gpio_swnode_consumer_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct gpio_swnode_consumer_pdata *pdata = dev_get_platdata(dev); + struct gpio_desc *desc; + + desc = devm_gpiod_get(dev, "foo", GPIOD_OUT_HIGH); + if (IS_ERR(desc)) + return PTR_ERR(desc); + + pdata->gpio_ok = true; + + return 0; +} + +static struct platform_driver gpio_swnode_consumer_driver = { + .probe = gpio_swnode_consumer_probe, + .driver = { + .name = GPIO_SWNODE_TEST_CONSUMER, + }, +}; + +static void gpio_swnode_lookup_by_primary(struct kunit *test) +{ + struct gpio_swnode_consumer_pdata *pdata; + struct platform_device_info pdevinfo; + struct property_entry properties[2]; + struct platform_device *pdev; + bool bound = false; + int ret; + + ret = kunit_platform_driver_register(test, &gpio_test_provider_driver); + KUNIT_ASSERT_EQ(test, ret, 0); + + ret = kunit_platform_driver_register(test, &gpio_swnode_consumer_driver); + KUNIT_ASSERT_EQ(test, ret, 0); + + pdevinfo = (struct platform_device_info){ + .name = GPIO_TEST_PROVIDER, + .id = PLATFORM_DEVID_NONE, + .swnode = &gpio_test_provider_swnode, + }; + + pdev = kunit_platform_device_register_full(test, &pdevinfo); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, pdev); + + properties[0] = PROPERTY_ENTRY_GPIO("foo-gpios", + &gpio_test_provider_swnode, + 0, GPIO_ACTIVE_HIGH); + properties[1] = (struct property_entry){ }; + + pdevinfo = (struct platform_device_info){ + .name = GPIO_SWNODE_TEST_CONSUMER, + .id = PLATFORM_DEVID_NONE, + .data = &gpio_swnode_pdata_template, + .size_data = sizeof(gpio_swnode_pdata_template), + .properties = properties, + }; + + pdev = kunit_platform_device_register_full(test, &pdevinfo); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, pdev); + + wait_for_device_probe(); + scoped_guard(device, &pdev->dev) + bound = device_is_bound(&pdev->dev); + + KUNIT_ASSERT_TRUE(test, bound); + + pdata = dev_get_platdata(&pdev->dev); + KUNIT_ASSERT_TRUE(test, pdata->gpio_ok); +} + +static void gpio_swnode_lookup_by_secondary(struct kunit *test) +{ + struct gpio_swnode_consumer_pdata *pdata; + struct platform_device_info pdevinfo; + struct property_entry properties[2]; + struct fwnode_handle *primary; + struct platform_device *pdev; + bool bound = false; + int ret; + + /* + * Can't live on the stack as it will still get referenced in cleanup + * path after this function returns. + */ + primary = kunit_kzalloc(test, sizeof(*primary), GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, primary); + + ret = kunit_platform_driver_register(test, &gpio_test_provider_driver); + KUNIT_ASSERT_EQ(test, ret, 0); + + ret = kunit_platform_driver_register(test, &gpio_swnode_consumer_driver); + KUNIT_ASSERT_EQ(test, ret, 0); + + fwnode_init(primary, NULL); + + pdevinfo = (struct platform_device_info){ + .name = GPIO_TEST_PROVIDER, + .id = PLATFORM_DEVID_NONE, + .fwnode = primary, + .swnode = &gpio_test_provider_swnode, + }; + + pdev = kunit_platform_device_register_full(test, &pdevinfo); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, pdev); + + properties[0] = PROPERTY_ENTRY_GPIO("foo-gpios", + &gpio_test_provider_swnode, + 0, GPIO_ACTIVE_HIGH); + properties[1] = (struct property_entry){ }; + + pdevinfo = (struct platform_device_info){ + .name = GPIO_SWNODE_TEST_CONSUMER, + .id = PLATFORM_DEVID_NONE, + .data = &gpio_swnode_pdata_template, + .size_data = sizeof(gpio_swnode_pdata_template), + .properties = properties, + }; + + pdev = kunit_platform_device_register_full(test, &pdevinfo); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, pdev); + + wait_for_device_probe(); + scoped_guard(device, &pdev->dev) + bound = device_is_bound(&pdev->dev); + + KUNIT_ASSERT_TRUE(test, bound); + + pdata = dev_get_platdata(&pdev->dev); + KUNIT_ASSERT_TRUE(test, pdata->gpio_ok); +} + +static struct kunit_case gpio_swnode_lookup_tests[] = { + KUNIT_CASE(gpio_swnode_lookup_by_primary), + KUNIT_CASE(gpio_swnode_lookup_by_secondary), + { } +}; + +static struct kunit_suite gpio_swnode_lookup_test_suite = { + .name = "gpio-swnode-lookup", + .test_cases = gpio_swnode_lookup_tests, +}; + +static BLOCKING_NOTIFIER_HEAD(gpio_unbind_notifier); + +struct gpio_unbind_consumer_drvdata { + struct device *dev; + struct gpio_desc *desc; + struct notifier_block nb; + int set_retval; +}; + +static int gpio_unbind_notify(struct notifier_block *nb, unsigned long action, + void *data) +{ + struct gpio_unbind_consumer_drvdata *drvdata = + container_of(nb, struct gpio_unbind_consumer_drvdata, nb); + struct device *dev = data; + + if (dev != drvdata->dev) + return NOTIFY_DONE; + + drvdata->set_retval = gpiod_set_value_cansleep(drvdata->desc, 0); + + return NOTIFY_OK; +} + +static void gpio_unbind_unregister_notifier(void *data) +{ + struct notifier_block *nb = data; + + blocking_notifier_chain_unregister(&gpio_unbind_notifier, nb); +} + +static int gpio_unbind_consumer_probe(struct platform_device *pdev) +{ + struct gpio_unbind_consumer_drvdata *data; + struct device *dev = &pdev->dev; + int ret; + + data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->dev = dev; + + data->desc = devm_gpiod_get(dev, "foo", GPIOD_OUT_HIGH); + if (IS_ERR(data->desc)) + return PTR_ERR(data->desc); + + data->nb.notifier_call = gpio_unbind_notify; + ret = blocking_notifier_chain_register(&gpio_unbind_notifier, &data->nb); + if (ret) + return ret; + + ret = devm_add_action_or_reset(dev, gpio_unbind_unregister_notifier, &data->nb); + if (ret) + return ret; + + platform_set_drvdata(pdev, data); + + return 0; +} + +static struct platform_driver gpio_unbind_consumer_driver = { + .probe = gpio_unbind_consumer_probe, + .driver = { + .name = GPIO_UNBIND_TEST_CONSUMER, + }, +}; + +static void gpio_unbind_with_consumers(struct kunit *test) +{ + struct gpio_unbind_consumer_drvdata *cons_data; + struct platform_device_info pdevinfo; + struct property_entry properties[2]; + struct platform_device *prvd, *cons; + bool bound = false; + int ret; + + ret = kunit_platform_driver_register(test, &gpio_test_provider_driver); + KUNIT_ASSERT_EQ(test, ret, 0); + + ret = kunit_platform_driver_register(test, &gpio_unbind_consumer_driver); + KUNIT_ASSERT_EQ(test, ret, 0); + + pdevinfo = (struct platform_device_info){ + .name = GPIO_TEST_PROVIDER, + .id = PLATFORM_DEVID_NONE, + .swnode = &gpio_test_provider_swnode, + }; + + prvd = kunit_platform_device_register_full(test, &pdevinfo); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, prvd); + + properties[0] = PROPERTY_ENTRY_GPIO("foo-gpios", + &gpio_test_provider_swnode, + 0, GPIO_ACTIVE_HIGH); + properties[1] = (struct property_entry){ }; + + pdevinfo = (struct platform_device_info){ + .name = GPIO_UNBIND_TEST_CONSUMER, + .id = PLATFORM_DEVID_NONE, + .properties = properties, + }; + + cons = kunit_platform_device_register_full(test, &pdevinfo); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, cons); + + wait_for_device_probe(); + scoped_guard(device, &cons->dev) + bound = device_is_bound(&cons->dev); + + KUNIT_ASSERT_TRUE(test, bound); + + kunit_platform_device_unregister(test, prvd); + + ret = blocking_notifier_call_chain(&gpio_unbind_notifier, 0, &cons->dev); + KUNIT_ASSERT_EQ(test, ret, NOTIFY_OK); + + scoped_guard(device, &cons->dev) { + cons_data = platform_get_drvdata(cons); + ret = cons_data->set_retval; + } + + KUNIT_ASSERT_EQ(test, ret, -ENODEV); +} + +static struct kunit_case gpio_unbind_with_consumers_tests[] = { + KUNIT_CASE(gpio_unbind_with_consumers), + { } +}; + +static struct kunit_suite gpio_unbind_with_consumers_test_suite = { + .name = "gpio-unbind-with-consumers", + .test_cases = gpio_unbind_with_consumers_tests, +}; + +kunit_test_suites( + &gpio_swnode_lookup_test_suite, + &gpio_unbind_with_consumers_test_suite, +); + +MODULE_DESCRIPTION("Test module for the GPIO subsystem"); +MODULE_AUTHOR("Bartosz Golaszewski <[email protected]>"); +MODULE_LICENSE("GPL"); -- 2.47.3
