xref: /linux/drivers/leds/led-test.c (revision 0ce92d548b44649a8de706f9bb9e74a4ed2f18a7)
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 
15 struct led_test_ddata {
16 	struct led_classdev cdev;
17 	struct device *dev;
18 };
19 
20 static enum led_brightness led_test_brightness_get(struct led_classdev *cdev)
21 {
22 	return LED_TEST_POST_REG_BRIGHTNESS;
23 }
24 
25 static 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 
60 static 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 
88 static 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 
94 static 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 
114 static 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 
122 static 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 };
128 kunit_test_suite(led_test_suite);
129 
130 MODULE_AUTHOR("Lee Jones <lee@kernel.org>");
131 MODULE_DESCRIPTION("KUnit tests for the LED framework");
132 MODULE_LICENSE("GPL");
133