xref: /openbmc/linux/arch/sh/kernel/time.c (revision ddc141e5)
1 /*
2  *  arch/sh/kernel/time.c
3  *
4  *  Copyright (C) 1999  Tetsuya Okada & Niibe Yutaka
5  *  Copyright (C) 2000  Philipp Rumpf <prumpf@tux.org>
6  *  Copyright (C) 2002 - 2009  Paul Mundt
7  *  Copyright (C) 2002  M. R. Brown  <mrbrown@linux-sh.org>
8  *
9  * This file is subject to the terms and conditions of the GNU General Public
10  * License.  See the file "COPYING" in the main directory of this archive
11  * for more details.
12  */
13 #include <linux/kernel.h>
14 #include <linux/init.h>
15 #include <linux/profile.h>
16 #include <linux/timex.h>
17 #include <linux/sched.h>
18 #include <linux/clockchips.h>
19 #include <linux/platform_device.h>
20 #include <linux/smp.h>
21 #include <linux/rtc.h>
22 #include <asm/clock.h>
23 #include <asm/rtc.h>
24 
25 /* Dummy RTC ops */
26 static void null_rtc_get_time(struct timespec *tv)
27 {
28 	tv->tv_sec = mktime(2000, 1, 1, 0, 0, 0);
29 	tv->tv_nsec = 0;
30 }
31 
32 static int null_rtc_set_time(const time_t secs)
33 {
34 	return 0;
35 }
36 
37 void (*rtc_sh_get_time)(struct timespec *) = null_rtc_get_time;
38 int (*rtc_sh_set_time)(const time_t) = null_rtc_set_time;
39 
40 void read_persistent_clock(struct timespec *ts)
41 {
42 	rtc_sh_get_time(ts);
43 }
44 
45 #ifdef CONFIG_GENERIC_CMOS_UPDATE
46 int update_persistent_clock(struct timespec now)
47 {
48 	return rtc_sh_set_time(now.tv_sec);
49 }
50 #endif
51 
52 static int rtc_generic_get_time(struct device *dev, struct rtc_time *tm)
53 {
54 	struct timespec tv;
55 
56 	rtc_sh_get_time(&tv);
57 	rtc_time_to_tm(tv.tv_sec, tm);
58 	return 0;
59 }
60 
61 static int rtc_generic_set_time(struct device *dev, struct rtc_time *tm)
62 {
63 	unsigned long secs;
64 
65 	rtc_tm_to_time(tm, &secs);
66 	if ((rtc_sh_set_time == null_rtc_set_time) ||
67 	    (rtc_sh_set_time(secs) < 0))
68 		return -EOPNOTSUPP;
69 
70 	return 0;
71 }
72 
73 static const struct rtc_class_ops rtc_generic_ops = {
74 	.read_time = rtc_generic_get_time,
75 	.set_time = rtc_generic_set_time,
76 };
77 
78 static int __init rtc_generic_init(void)
79 {
80 	struct platform_device *pdev;
81 
82 	if (rtc_sh_get_time == null_rtc_get_time)
83 		return -ENODEV;
84 
85 	pdev = platform_device_register_data(NULL, "rtc-generic", -1,
86 					     &rtc_generic_ops,
87 					     sizeof(rtc_generic_ops));
88 
89 
90 	return PTR_ERR_OR_ZERO(pdev);
91 }
92 device_initcall(rtc_generic_init);
93 
94 void (*board_time_init)(void);
95 
96 static void __init sh_late_time_init(void)
97 {
98 	/*
99 	 * Make sure all compiled-in early timers register themselves.
100 	 *
101 	 * Run probe() for two "earlytimer" devices, these will be the
102 	 * clockevents and clocksource devices respectively. In the event
103 	 * that only a clockevents device is available, we -ENODEV on the
104 	 * clocksource and the jiffies clocksource is used transparently
105 	 * instead. No error handling is necessary here.
106 	 */
107 	early_platform_driver_register_all("earlytimer");
108 	early_platform_driver_probe("earlytimer", 2, 0);
109 }
110 
111 void __init time_init(void)
112 {
113 	if (board_time_init)
114 		board_time_init();
115 
116 	clk_init();
117 
118 	late_time_init = sh_late_time_init;
119 }
120