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
15 struct rtc_test_data {
16 struct rtc_device *rtc;
17 time64_t offset;
18 struct timer_list alarm;
19 bool alarm_en;
20 };
21
22 static struct platform_device *pdev[MAX_RTC_TEST];
23
test_rtc_read_alarm(struct device * dev,struct rtc_wkalrm * alrm)24 static 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
test_rtc_set_alarm(struct device * dev,struct rtc_wkalrm * alrm)38 static 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
test_rtc_read_time(struct device * dev,struct rtc_time * tm)63 static 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
test_rtc_set_time(struct device * dev,struct rtc_time * tm)72 static 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
test_rtc_alarm_irq_enable(struct device * dev,unsigned int enable)81 static 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
94 static 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
100 static 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
test_rtc_alarm_handler(struct timer_list * t)108 static 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
test_probe(struct platform_device * plat_dev)115 static 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, true);
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
144 static struct platform_driver test_driver = {
145 .probe = test_probe,
146 .driver = {
147 .name = "rtc-test",
148 },
149 };
150
test_init(void)151 static 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
174 exit_device_del:
175 for (; i > 0; i--)
176 platform_device_del(pdev[i - 1]);
177
178 exit_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
test_exit(void)186 static 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
196 MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");
197 MODULE_DESCRIPTION("RTC test driver/device");
198 MODULE_LICENSE("GPL v2");
199
200 module_init(test_init);
201 module_exit(test_exit);
202