led-test.c

  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Copyright (C) 2025 Google LLC
  4 *
  5 * Author: Lee Jones <lee@kernel.org>
  6 */
  7
  8#include <kunit/device.h>
  9#include <kunit/test.h>
 10#include <linux/device.h>
 11#include <linux/leds.h>
 12
 13#define LED_TEST_POST_REG_BRIGHTNESS 10
 14
 15struct led_test_ddata {
 16	struct led_classdev cdev;
 17	struct device *dev;
 18};
 19
 20static enum led_brightness led_test_brightness_get(struct led_classdev *cdev)
 21{
 22	return LED_TEST_POST_REG_BRIGHTNESS;
 23}
 24
 25static void led_test_class_register(struct kunit *test)
 26{
 27	struct led_test_ddata *ddata = test->priv;
 28	struct led_classdev *cdev_clash, *cdev = &ddata->cdev;
 29	struct device *dev = ddata->dev;
 30	int ret;
 31
 32	/* Register a LED class device */
 33	cdev->name = "led-test";
 34	cdev->brightness_get = led_test_brightness_get;
 35	cdev->brightness = 0;
 36
 37	ret = devm_led_classdev_register(dev, cdev);
 38	KUNIT_ASSERT_EQ(test, ret, 0);
 39
 40	KUNIT_EXPECT_EQ(test, cdev->max_brightness, LED_FULL);
 41	KUNIT_EXPECT_EQ(test, cdev->brightness, LED_TEST_POST_REG_BRIGHTNESS);
 42	KUNIT_EXPECT_STREQ(test, cdev->dev->kobj.name, "led-test");
 43
 44	/* Register again with the same name - expect it to pass with the LED renamed */
 45	cdev_clash = devm_kmemdup(dev, cdev, sizeof(*cdev), GFP_KERNEL);
 46	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, cdev_clash);
 47
 48	ret = devm_led_classdev_register(dev, cdev_clash);
 49	KUNIT_ASSERT_EQ(test, ret, 0);
 50
 51	KUNIT_EXPECT_STREQ(test, cdev_clash->dev->kobj.name, "led-test_1");
 52	KUNIT_EXPECT_STREQ(test, cdev_clash->name, "led-test");
 53
 54	/* Enable name conflict rejection and register with the same name again - expect failure */
 55	cdev_clash->flags |= LED_REJECT_NAME_CONFLICT;
 56	ret = devm_led_classdev_register(dev, cdev_clash);
 57	KUNIT_EXPECT_EQ(test, ret, -EEXIST);
 58}
 59
 60static void led_test_class_add_lookup_and_get(struct kunit *test)
 61{
 62	struct led_test_ddata *ddata = test->priv;
 63	struct led_classdev *cdev = &ddata->cdev, *cdev_get;
 64	struct device *dev = ddata->dev;
 65	struct led_lookup_data lookup;
 66	int ret;
 67
 68	/* First, register a LED class device */
 69	cdev->name = "led-test";
 70	ret = devm_led_classdev_register(dev, cdev);
 71	KUNIT_ASSERT_EQ(test, ret, 0);
 72
 73	/* Then make the LED available for lookup */
 74	lookup.provider = cdev->name;
 75	lookup.dev_id = dev_name(dev);
 76	lookup.con_id = "led-test-1";
 77	led_add_lookup(&lookup);
 78
 79	/* Finally, attempt to look it up via the API - imagine this was an orthogonal driver */
 80	cdev_get = devm_led_get(dev, "led-test-1");
 81	KUNIT_ASSERT_FALSE(test, IS_ERR(cdev_get));
 82
 83	KUNIT_EXPECT_STREQ(test, cdev_get->name, cdev->name);
 84
 85	led_remove_lookup(&lookup);
 86}
 87
 88static struct kunit_case led_test_cases[] = {
 89	KUNIT_CASE(led_test_class_register),
 90	KUNIT_CASE(led_test_class_add_lookup_and_get),
 91	{ }
 92};
 93
 94static int led_test_init(struct kunit *test)
 95{
 96	struct led_test_ddata *ddata;
 97	struct device *dev;
 98
 99	ddata = kunit_kzalloc(test, sizeof(*ddata), GFP_KERNEL);
100	if (!ddata)
101		return -ENOMEM;
102
103	test->priv = ddata;
104
105	dev = kunit_device_register(test, "led_test");
106	if (IS_ERR(dev))
107		return PTR_ERR(dev);
108
109	ddata->dev = get_device(dev);
110
111	return 0;
112}
113
114static void led_test_exit(struct kunit *test)
115{
116	struct led_test_ddata *ddata = test->priv;
117
118	if (ddata && ddata->dev)
119		put_device(ddata->dev);
120}
121
122static struct kunit_suite led_test_suite = {
123	.name = "led",
124	.init = led_test_init,
125	.exit = led_test_exit,
126	.test_cases = led_test_cases,
127};
128kunit_test_suite(led_test_suite);
129
130MODULE_AUTHOR("Lee Jones <lee@kernel.org>");
131MODULE_DESCRIPTION("KUnit tests for the LED framework");
132MODULE_LICENSE("GPL");