2 * linux/arch/arm/common/rtctime.c
4 * Copyright (C) 2003 Deep Blue Solutions Ltd.
5 * Based on sa1100-rtc.c, Nils Faerber, CIH, Nicolas Pitre.
6 * Based on rtc.c by Paul Gortmaker
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
12 #include <linux/module.h>
13 #include <linux/kernel.h>
14 #include <linux/time.h>
15 #include <linux/rtc.h>
16 #include <linux/poll.h>
17 #include <linux/proc_fs.h>
18 #include <linux/miscdevice.h>
19 #include <linux/spinlock.h>
20 #include <linux/device.h>
21 #include <linux/mutex.h>
24 #include <asm/semaphore.h>
26 static DECLARE_WAIT_QUEUE_HEAD(rtc_wait);
27 static struct fasync_struct *rtc_async_queue;
30 * rtc_lock protects rtc_irq_data
32 static DEFINE_SPINLOCK(rtc_lock);
33 static unsigned long rtc_irq_data;
36 * rtc_sem protects rtc_inuse and rtc_ops
38 static DEFINE_MUTEX(rtc_mutex);
39 static unsigned long rtc_inuse;
40 static struct rtc_ops *rtc_ops;
42 #define rtc_epoch 1900UL
44 static const unsigned char days_in_month[] = {
45 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
48 #define LEAPS_THRU_END_OF(y) ((y)/4 - (y)/100 + (y)/400)
49 #define LEAP_YEAR(year) ((!(year % 4) && (year % 100)) || !(year % 400))
51 static int month_days(unsigned int month, unsigned int year)
53 return days_in_month[month] + (LEAP_YEAR(year) && month == 1);
57 * Convert seconds since 01-01-1970 00:00:00 to Gregorian date.
59 void rtc_time_to_tm(unsigned long time, struct rtc_time *tm)
61 int days, month, year;
66 tm->tm_wday = (days + 4) % 7;
68 year = 1970 + days / 365;
69 days -= (year - 1970) * 365
70 + LEAPS_THRU_END_OF(year - 1)
71 - LEAPS_THRU_END_OF(1970 - 1);
74 days += 365 + LEAP_YEAR(year);
76 tm->tm_year = year - 1900;
77 tm->tm_yday = days + 1;
79 for (month = 0; month < 11; month++) {
82 newdays = days - month_days(month, year);
88 tm->tm_mday = days + 1;
90 tm->tm_hour = time / 3600;
91 time -= tm->tm_hour * 3600;
92 tm->tm_min = time / 60;
93 tm->tm_sec = time - tm->tm_min * 60;
95 EXPORT_SYMBOL(rtc_time_to_tm);
98 * Does the rtc_time represent a valid date/time?
100 int rtc_valid_tm(struct rtc_time *tm)
102 if (tm->tm_year < 70 ||
105 tm->tm_mday > month_days(tm->tm_mon, tm->tm_year + 1900) ||
113 EXPORT_SYMBOL(rtc_valid_tm);
116 * Convert Gregorian date to seconds since 01-01-1970 00:00:00.
118 int rtc_tm_to_time(struct rtc_time *tm, unsigned long *time)
120 *time = mktime(tm->tm_year + 1900, tm->tm_mon + 1, tm->tm_mday,
121 tm->tm_hour, tm->tm_min, tm->tm_sec);
125 EXPORT_SYMBOL(rtc_tm_to_time);
128 * Calculate the next alarm time given the requested alarm time mask
129 * and the current time.
131 * FIXME: for now, we just copy the alarm time because we're lazy (and
132 * is therefore buggy - setting a 10am alarm at 8pm will not result in
133 * the alarm triggering.)
135 void rtc_next_alarm_time(struct rtc_time *next, struct rtc_time *now, struct rtc_time *alrm)
137 next->tm_year = now->tm_year;
138 next->tm_mon = now->tm_mon;
139 next->tm_mday = now->tm_mday;
140 next->tm_hour = alrm->tm_hour;
141 next->tm_min = alrm->tm_min;
142 next->tm_sec = alrm->tm_sec;
145 static inline int rtc_read_time(struct rtc_ops *ops, struct rtc_time *tm)
147 memset(tm, 0, sizeof(struct rtc_time));
148 return ops->read_time(tm);
151 static inline int rtc_set_time(struct rtc_ops *ops, struct rtc_time *tm)
155 ret = rtc_valid_tm(tm);
157 ret = ops->set_time(tm);
162 static inline int rtc_read_alarm(struct rtc_ops *ops, struct rtc_wkalrm *alrm)
165 if (ops->read_alarm) {
166 memset(alrm, 0, sizeof(struct rtc_wkalrm));
167 ret = ops->read_alarm(alrm);
172 static inline int rtc_set_alarm(struct rtc_ops *ops, struct rtc_wkalrm *alrm)
176 ret = ops->set_alarm(alrm);
180 void rtc_update(unsigned long num, unsigned long events)
182 spin_lock(&rtc_lock);
183 rtc_irq_data = (rtc_irq_data + (num << 8)) | events;
184 spin_unlock(&rtc_lock);
186 wake_up_interruptible(&rtc_wait);
187 kill_fasync(&rtc_async_queue, SIGIO, POLL_IN);
189 EXPORT_SYMBOL(rtc_update);
193 rtc_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
195 DECLARE_WAITQUEUE(wait, current);
199 if (count < sizeof(unsigned long))
202 add_wait_queue(&rtc_wait, &wait);
204 __set_current_state(TASK_INTERRUPTIBLE);
206 spin_lock_irq(&rtc_lock);
209 spin_unlock_irq(&rtc_lock);
215 if (file->f_flags & O_NONBLOCK) {
219 if (signal_pending(current)) {
225 set_current_state(TASK_RUNNING);
226 remove_wait_queue(&rtc_wait, &wait);
229 ret = put_user(data, (unsigned long __user *)buf);
231 ret = sizeof(unsigned long);
236 static unsigned int rtc_poll(struct file *file, poll_table *wait)
240 poll_wait(file, &rtc_wait, wait);
242 spin_lock_irq(&rtc_lock);
244 spin_unlock_irq(&rtc_lock);
246 return data != 0 ? POLLIN | POLLRDNORM : 0;
249 static int rtc_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
252 struct rtc_ops *ops = file->private_data;
254 struct rtc_wkalrm alrm;
255 void __user *uarg = (void __user *)arg;
260 ret = rtc_read_alarm(ops, &alrm);
263 ret = copy_to_user(uarg, &alrm.time, sizeof(tm));
269 ret = copy_from_user(&alrm.time, uarg, sizeof(tm));
276 alrm.time.tm_mday = -1;
277 alrm.time.tm_mon = -1;
278 alrm.time.tm_year = -1;
279 alrm.time.tm_wday = -1;
280 alrm.time.tm_yday = -1;
281 alrm.time.tm_isdst = -1;
282 ret = rtc_set_alarm(ops, &alrm);
286 ret = rtc_read_time(ops, &tm);
289 ret = copy_to_user(uarg, &tm, sizeof(tm));
295 if (!capable(CAP_SYS_TIME)) {
299 ret = copy_from_user(&tm, uarg, sizeof(tm));
304 ret = rtc_set_time(ops, &tm);
310 * There were no RTC clocks before 1900.
316 if (!capable(CAP_SYS_TIME)) {
326 ret = put_user(rtc_epoch, (unsigned long __user *)uarg);
330 ret = copy_from_user(&alrm, uarg, sizeof(alrm));
335 ret = rtc_set_alarm(ops, &alrm);
339 ret = rtc_read_alarm(ops, &alrm);
342 ret = copy_to_user(uarg, &alrm, sizeof(alrm));
349 ret = ops->ioctl(cmd, arg);
355 static int rtc_open(struct inode *inode, struct file *file)
359 mutex_lock(&rtc_mutex);
363 } else if (!rtc_ops || !try_module_get(rtc_ops->owner)) {
366 file->private_data = rtc_ops;
368 ret = rtc_ops->open ? rtc_ops->open() : 0;
370 spin_lock_irq(&rtc_lock);
372 spin_unlock_irq(&rtc_lock);
377 mutex_unlock(&rtc_mutex);
382 static int rtc_release(struct inode *inode, struct file *file)
384 struct rtc_ops *ops = file->private_data;
389 spin_lock_irq(&rtc_lock);
391 spin_unlock_irq(&rtc_lock);
393 module_put(rtc_ops->owner);
399 static int rtc_fasync(int fd, struct file *file, int on)
401 return fasync_helper(fd, file, on, &rtc_async_queue);
404 static struct file_operations rtc_fops = {
405 .owner = THIS_MODULE,
411 .release = rtc_release,
412 .fasync = rtc_fasync,
415 static struct miscdevice rtc_miscdev = {
422 static int rtc_read_proc(char *page, char **start, off_t off, int count, int *eof, void *data)
424 struct rtc_ops *ops = data;
425 struct rtc_wkalrm alrm;
429 if (rtc_read_time(ops, &tm) == 0) {
431 "rtc_time\t: %02d:%02d:%02d\n"
432 "rtc_date\t: %04d-%02d-%02d\n"
433 "rtc_epoch\t: %04lu\n",
434 tm.tm_hour, tm.tm_min, tm.tm_sec,
435 tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday,
439 if (rtc_read_alarm(ops, &alrm) == 0) {
440 p += sprintf(p, "alrm_time\t: ");
441 if ((unsigned int)alrm.time.tm_hour <= 24)
442 p += sprintf(p, "%02d:", alrm.time.tm_hour);
444 p += sprintf(p, "**:");
445 if ((unsigned int)alrm.time.tm_min <= 59)
446 p += sprintf(p, "%02d:", alrm.time.tm_min);
448 p += sprintf(p, "**:");
449 if ((unsigned int)alrm.time.tm_sec <= 59)
450 p += sprintf(p, "%02d\n", alrm.time.tm_sec);
452 p += sprintf(p, "**\n");
454 p += sprintf(p, "alrm_date\t: ");
455 if ((unsigned int)alrm.time.tm_year <= 200)
456 p += sprintf(p, "%04d-", alrm.time.tm_year + 1900);
458 p += sprintf(p, "****-");
459 if ((unsigned int)alrm.time.tm_mon <= 11)
460 p += sprintf(p, "%02d-", alrm.time.tm_mon + 1);
462 p += sprintf(p, "**-");
463 if ((unsigned int)alrm.time.tm_mday <= 31)
464 p += sprintf(p, "%02d\n", alrm.time.tm_mday);
466 p += sprintf(p, "**\n");
467 p += sprintf(p, "alrm_wakeup\t: %s\n",
468 alrm.enabled ? "yes" : "no");
469 p += sprintf(p, "alrm_pending\t: %s\n",
470 alrm.pending ? "yes" : "no");
479 int register_rtc(struct rtc_ops *ops)
483 mutex_lock(&rtc_mutex);
484 if (rtc_ops == NULL) {
487 ret = misc_register(&rtc_miscdev);
489 create_proc_read_entry("driver/rtc", 0, NULL,
492 mutex_unlock(&rtc_mutex);
496 EXPORT_SYMBOL(register_rtc);
498 void unregister_rtc(struct rtc_ops *rtc)
500 mutex_lock(&rtc_mutex);
501 if (rtc == rtc_ops) {
502 remove_proc_entry("driver/rtc", NULL);
503 misc_deregister(&rtc_miscdev);
506 mutex_unlock(&rtc_mutex);
508 EXPORT_SYMBOL(unregister_rtc);