xref: /openbmc/linux/drivers/rtc/rtc-generic.c (revision 39b6f3aa)
1 /* rtc-generic: RTC driver using the generic RTC abstraction
2  *
3  * Copyright (C) 2008 Kyle McMartin <kyle@mcmartin.ca>
4  */
5 
6 #include <linux/kernel.h>
7 #include <linux/module.h>
8 #include <linux/time.h>
9 #include <linux/platform_device.h>
10 #include <linux/rtc.h>
11 
12 #include <asm/rtc.h>
13 
14 static int generic_get_time(struct device *dev, struct rtc_time *tm)
15 {
16 	unsigned int ret = get_rtc_time(tm);
17 
18 	if (ret & RTC_BATT_BAD)
19 		return -EOPNOTSUPP;
20 
21 	return rtc_valid_tm(tm);
22 }
23 
24 static int generic_set_time(struct device *dev, struct rtc_time *tm)
25 {
26 	if (set_rtc_time(tm) < 0)
27 		return -EOPNOTSUPP;
28 
29 	return 0;
30 }
31 
32 static const struct rtc_class_ops generic_rtc_ops = {
33 	.read_time = generic_get_time,
34 	.set_time = generic_set_time,
35 };
36 
37 static int __init generic_rtc_probe(struct platform_device *dev)
38 {
39 	struct rtc_device *rtc;
40 
41 	rtc = devm_rtc_device_register(&dev->dev, "rtc-generic",
42 					&generic_rtc_ops, THIS_MODULE);
43 	if (IS_ERR(rtc))
44 		return PTR_ERR(rtc);
45 
46 	platform_set_drvdata(dev, rtc);
47 
48 	return 0;
49 }
50 
51 static int __exit generic_rtc_remove(struct platform_device *dev)
52 {
53 	return 0;
54 }
55 
56 static struct platform_driver generic_rtc_driver = {
57 	.driver = {
58 		.name = "rtc-generic",
59 		.owner = THIS_MODULE,
60 	},
61 	.remove = __exit_p(generic_rtc_remove),
62 };
63 
64 module_platform_driver_probe(generic_rtc_driver, generic_rtc_probe);
65 
66 MODULE_AUTHOR("Kyle McMartin <kyle@mcmartin.ca>");
67 MODULE_LICENSE("GPL");
68 MODULE_DESCRIPTION("Generic RTC driver");
69 MODULE_ALIAS("platform:rtc-generic");
70