xref: /openbmc/linux/drivers/rtc/rtc-ps3.c (revision 27ab1c1c)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * PS3 RTC Driver
4  *
5  * Copyright 2009 Sony Corporation
6  */
7 
8 #include <linux/kernel.h>
9 #include <linux/module.h>
10 #include <linux/platform_device.h>
11 #include <linux/rtc.h>
12 
13 #include <asm/lv1call.h>
14 #include <asm/ps3.h>
15 
16 
17 static u64 read_rtc(void)
18 {
19 	int result;
20 	u64 rtc_val;
21 	u64 tb_val;
22 
23 	result = lv1_get_rtc(&rtc_val, &tb_val);
24 	BUG_ON(result);
25 
26 	return rtc_val;
27 }
28 
29 static int ps3_get_time(struct device *dev, struct rtc_time *tm)
30 {
31 	rtc_time64_to_tm(read_rtc() + ps3_os_area_get_rtc_diff(), tm);
32 	return 0;
33 }
34 
35 static int ps3_set_time(struct device *dev, struct rtc_time *tm)
36 {
37 	ps3_os_area_set_rtc_diff(rtc_tm_to_time64(tm) - read_rtc());
38 	return 0;
39 }
40 
41 static const struct rtc_class_ops ps3_rtc_ops = {
42 	.read_time = ps3_get_time,
43 	.set_time = ps3_set_time,
44 };
45 
46 static int __init ps3_rtc_probe(struct platform_device *dev)
47 {
48 	struct rtc_device *rtc;
49 
50 	rtc = devm_rtc_allocate_device(&dev->dev);
51 	if (IS_ERR(rtc))
52 		return PTR_ERR(rtc);
53 
54 	rtc->ops = &ps3_rtc_ops;
55 	rtc->range_max = U64_MAX;
56 
57 	platform_set_drvdata(dev, rtc);
58 
59 	return devm_rtc_register_device(rtc);
60 }
61 
62 static struct platform_driver ps3_rtc_driver = {
63 	.driver = {
64 		.name = "rtc-ps3",
65 	},
66 };
67 
68 module_platform_driver_probe(ps3_rtc_driver, ps3_rtc_probe);
69 
70 MODULE_AUTHOR("Sony Corporation");
71 MODULE_LICENSE("GPL");
72 MODULE_DESCRIPTION("ps3 RTC driver");
73 MODULE_ALIAS("platform:rtc-ps3");
74