xref: /openbmc/linux/drivers/rtc/rtc-generic.c (revision 1ab142d4)
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 = rtc_device_register("rtc-generic", &dev->dev, &generic_rtc_ops,
42 				  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 	struct rtc_device *rtc = platform_get_drvdata(dev);
54 
55 	rtc_device_unregister(rtc);
56 
57 	return 0;
58 }
59 
60 static struct platform_driver generic_rtc_driver = {
61 	.driver = {
62 		.name = "rtc-generic",
63 		.owner = THIS_MODULE,
64 	},
65 	.remove = __exit_p(generic_rtc_remove),
66 };
67 
68 static int __init generic_rtc_init(void)
69 {
70 	return platform_driver_probe(&generic_rtc_driver, generic_rtc_probe);
71 }
72 
73 static void __exit generic_rtc_fini(void)
74 {
75 	platform_driver_unregister(&generic_rtc_driver);
76 }
77 
78 module_init(generic_rtc_init);
79 module_exit(generic_rtc_fini);
80 
81 MODULE_AUTHOR("Kyle McMartin <kyle@mcmartin.ca>");
82 MODULE_LICENSE("GPL");
83 MODULE_DESCRIPTION("Generic RTC driver");
84 MODULE_ALIAS("platform:rtc-generic");
85