1// SPDX-License-Identifier: GPL-2.0
2/*
3 * An RTC test device/driver
4 * Copyright (C) 2005 Tower Technologies
5 * Author: Alessandro Zummo <a.zummo@towertech.it>
6 */
7
8#include <linux/module.h>
9#include <linux/err.h>
10#include <linux/rtc.h>
11#include <linux/platform_device.h>
12
13#define MAX_RTC_TEST 3
14
15struct rtc_test_data {
16	struct rtc_device *rtc;
17	time64_t offset;
18	struct timer_list alarm;
19	bool alarm_en;
20};
21
22static struct platform_device *pdev[MAX_RTC_TEST];
23
24static int test_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
25{
26	struct rtc_test_data *rtd = dev_get_drvdata(dev);
27	time64_t alarm;
28
29	alarm = (rtd->alarm.expires - jiffies) / HZ;
30	alarm += ktime_get_real_seconds() + rtd->offset;
31
32	rtc_time64_to_tm(alarm, &alrm->time);
33	alrm->enabled = rtd->alarm_en;
34
35	return 0;
36}
37
38static int test_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
39{
40	struct rtc_test_data *rtd = dev_get_drvdata(dev);
41	ktime_t timeout;
42	u64 expires;
43
44	timeout = rtc_tm_to_time64(&alrm->time) - ktime_get_real_seconds();
45	timeout -= rtd->offset;
46
47	del_timer(&rtd->alarm);
48
49	expires = jiffies + timeout * HZ;
50	if (expires > U32_MAX)
51		expires = U32_MAX;
52
53	rtd->alarm.expires = expires;
54
55	if (alrm->enabled)
56		add_timer(&rtd->alarm);
57
58	rtd->alarm_en = alrm->enabled;
59
60	return 0;
61}
62
63static int test_rtc_read_time(struct device *dev, struct rtc_time *tm)
64{
65	struct rtc_test_data *rtd = dev_get_drvdata(dev);
66
67	rtc_time64_to_tm(ktime_get_real_seconds() + rtd->offset, tm);
68
69	return 0;
70}
71
72static int test_rtc_set_time(struct device *dev, struct rtc_time *tm)
73{
74	struct rtc_test_data *rtd = dev_get_drvdata(dev);
75
76	rtd->offset = rtc_tm_to_time64(tm) - ktime_get_real_seconds();
77
78	return 0;
79}
80
81static int test_rtc_alarm_irq_enable(struct device *dev, unsigned int enable)
82{
83	struct rtc_test_data *rtd = dev_get_drvdata(dev);
84
85	rtd->alarm_en = enable;
86	if (enable)
87		add_timer(&rtd->alarm);
88	else
89		del_timer(&rtd->alarm);
90
91	return 0;
92}
93
94static const struct rtc_class_ops test_rtc_ops_noalm = {
95	.read_time = test_rtc_read_time,
96	.set_time = test_rtc_set_time,
97	.alarm_irq_enable = test_rtc_alarm_irq_enable,
98};
99
100static const struct rtc_class_ops test_rtc_ops = {
101	.read_time = test_rtc_read_time,
102	.set_time = test_rtc_set_time,
103	.read_alarm = test_rtc_read_alarm,
104	.set_alarm = test_rtc_set_alarm,
105	.alarm_irq_enable = test_rtc_alarm_irq_enable,
106};
107
108static void test_rtc_alarm_handler(struct timer_list *t)
109{
110	struct rtc_test_data *rtd = from_timer(rtd, t, alarm);
111
112	rtc_update_irq(rtd->rtc, 1, RTC_AF | RTC_IRQF);
113}
114
115static int test_probe(struct platform_device *plat_dev)
116{
117	struct rtc_test_data *rtd;
118
119	rtd = devm_kzalloc(&plat_dev->dev, sizeof(*rtd), GFP_KERNEL);
120	if (!rtd)
121		return -ENOMEM;
122
123	platform_set_drvdata(plat_dev, rtd);
124
125	rtd->rtc = devm_rtc_allocate_device(&plat_dev->dev);
126	if (IS_ERR(rtd->rtc))
127		return PTR_ERR(rtd->rtc);
128
129	switch (plat_dev->id) {
130	case 0:
131		rtd->rtc->ops = &test_rtc_ops_noalm;
132		break;
133	default:
134		rtd->rtc->ops = &test_rtc_ops;
135		device_init_wakeup(&plat_dev->dev, 1);
136	}
137
138	timer_setup(&rtd->alarm, test_rtc_alarm_handler, 0);
139	rtd->alarm.expires = 0;
140
141	return devm_rtc_register_device(rtd->rtc);
142}
143
144static struct platform_driver test_driver = {
145	.probe	= test_probe,
146	.driver = {
147		.name = "rtc-test",
148	},
149};
150
151static int __init test_init(void)
152{
153	int i, err;
154
155	err = platform_driver_register(&test_driver);
156	if (err)
157		return err;
158
159	err = -ENOMEM;
160	for (i = 0; i < MAX_RTC_TEST; i++) {
161		pdev[i] = platform_device_alloc("rtc-test", i);
162		if (!pdev[i])
163			goto exit_free_mem;
164	}
165
166	for (i = 0; i < MAX_RTC_TEST; i++) {
167		err = platform_device_add(pdev[i]);
168		if (err)
169			goto exit_device_del;
170	}
171
172	return 0;
173
174exit_device_del:
175	for (; i > 0; i--)
176		platform_device_del(pdev[i - 1]);
177
178exit_free_mem:
179	for (i = 0; i < MAX_RTC_TEST; i++)
180		platform_device_put(pdev[i]);
181
182	platform_driver_unregister(&test_driver);
183	return err;
184}
185
186static void __exit test_exit(void)
187{
188	int i;
189
190	for (i = 0; i < MAX_RTC_TEST; i++)
191		platform_device_unregister(pdev[i]);
192
193	platform_driver_unregister(&test_driver);
194}
195
196MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");
197MODULE_DESCRIPTION("RTC test driver/device");
198MODULE_LICENSE("GPL v2");
199
200module_init(test_init);
201module_exit(test_exit);
202