1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright 2023 Maxime Ripard <mripard@kernel.org>
3 
4 #include <kunit/resource.h>
5 
6 #include <linux/device.h>
7 
8 #define DEVICE_NAME "test"
9 
10 struct test_priv {
11 	bool probe_done;
12 	bool release_done;
13 	wait_queue_head_t release_wq;
14 	struct device *dev;
15 };
16 
17 static int root_device_devm_init(struct kunit *test)
18 {
19 	struct test_priv *priv;
20 
21 	priv = kunit_kzalloc(test, sizeof(*priv), GFP_KERNEL);
22 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, priv);
23 	init_waitqueue_head(&priv->release_wq);
24 
25 	test->priv = priv;
26 
27 	return 0;
28 }
29 
30 static void devm_device_action(void *ptr)
31 {
32 	struct test_priv *priv = ptr;
33 
34 	priv->release_done = true;
35 	wake_up_interruptible(&priv->release_wq);
36 }
37 
38 #define RELEASE_TIMEOUT_MS	100
39 
40 /*
41  * Tests that a bus-less, non-probed device will run its device-managed
42  * actions when unregistered.
43  */
44 static void root_device_devm_register_unregister_test(struct kunit *test)
45 {
46 	struct test_priv *priv = test->priv;
47 	int ret;
48 
49 	priv->dev = root_device_register(DEVICE_NAME);
50 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, priv->dev);
51 
52 	ret = devm_add_action_or_reset(priv->dev, devm_device_action, priv);
53 	KUNIT_ASSERT_EQ(test, ret, 0);
54 
55 	root_device_unregister(priv->dev);
56 
57 	ret = wait_event_interruptible_timeout(priv->release_wq, priv->release_done,
58 					       msecs_to_jiffies(RELEASE_TIMEOUT_MS));
59 	KUNIT_EXPECT_GT(test, ret, 0);
60 }
61 
62 static void devm_put_device_action(void *ptr)
63 {
64 	struct test_priv *priv = ptr;
65 
66 	put_device(priv->dev);
67 	priv->release_done = true;
68 	wake_up_interruptible(&priv->release_wq);
69 }
70 
71 /*
72  * Tests that a bus-less, non-probed device will run its device-managed
73  * actions when unregistered, even if someone still holds a reference to
74  * it.
75  */
76 static void root_device_devm_register_get_unregister_with_devm_test(struct kunit *test)
77 {
78 	struct test_priv *priv = test->priv;
79 	int ret;
80 
81 	priv->dev = root_device_register(DEVICE_NAME);
82 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, priv->dev);
83 
84 	get_device(priv->dev);
85 
86 	ret = devm_add_action_or_reset(priv->dev, devm_put_device_action, priv);
87 	KUNIT_ASSERT_EQ(test, ret, 0);
88 
89 	root_device_unregister(priv->dev);
90 
91 	ret = wait_event_interruptible_timeout(priv->release_wq, priv->release_done,
92 					       msecs_to_jiffies(RELEASE_TIMEOUT_MS));
93 	KUNIT_EXPECT_GT(test, ret, 0);
94 }
95 
96 static struct kunit_case root_device_devm_tests[] = {
97 	KUNIT_CASE(root_device_devm_register_unregister_test),
98 	KUNIT_CASE(root_device_devm_register_get_unregister_with_devm_test),
99 	{}
100 };
101 
102 static struct kunit_suite root_device_devm_test_suite = {
103 	.name = "root-device-devm",
104 	.init = root_device_devm_init,
105 	.test_cases = root_device_devm_tests,
106 };
107 
108 kunit_test_suite(root_device_devm_test_suite);
109 
110 MODULE_DESCRIPTION("Test module for root devices");
111 MODULE_AUTHOR("Maxime Ripard <mripard@kernel.org>");
112 MODULE_LICENSE("GPL");
113