/*
* linux/arch/arm/common/rtctime.c
*
* Copyright (C) 2003 Deep Blue Solutions Ltd.
* Based on sa1100-rtc.c, Nils Faerber, CIH, Nicolas Pitre.
* Based on rtc.c by Paul Gortmaker
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/time.h>
#include <linux/rtc.h>
#include <linux/poll.h>
#include <linux/proc_fs.h>
#include <linux/miscdevice.h>
#include <linux/spinlock.h>
#include <linux/device.h>
#include <asm/rtc.h>
#include <asm/semaphore.h>
static DECLARE_WAIT_QUEUE_HEAD(rtc_wait);
static struct fasync_struct *rtc_async_queue;
/*
* rtc_lock protects rtc_irq_data
*/
static DEFINE_SPINLOCK(rtc_lock);
static unsigned long rtc_irq_data;
/*
* rtc_sem protects rtc_inuse and rtc_ops
*/
static DECLARE_MUTEX(rtc_sem);
static unsigned long rtc_inuse;
static struct rtc_ops *rtc_ops;
#define rtc_epoch 1900UL
static const unsigned char days_in_month[] = {
31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
};
#define LEAPS_THRU_END_OF(y) ((y)/4 - (y)/100 + (y)/400)
#define LEAP_YEAR(year) ((!(year % 4) && (year % 100)) || !(year % 400))
static int month_days(unsigned int month, unsigned int year)
{
return days_in_month[month] + (LEAP_YEAR(year) && month == 1);
}
/*
* Convert seconds since 01-01-1970 00:00:00 to Gregorian date.
*/
void rtc_time_to_tm(unsigned long time, struct rtc_time *tm)
{
int days, month, year;
days = time / 86400;
time -= days * 86400;
tm->tm_wday = (days + 4) % 7;
year = 1970 + days / 365;
days -= (year - 1970) * 365
+ LEAPS_THRU_END_OF(year - 1)
- LEAPS_THRU_END_OF(1970 - 1);
if (days < 0) {
year -= 1;
days += 365 + LEAP_YEAR(year);
}
tm->tm_year = year - 1900;
tm->tm_yday = days + 1;
for (month = 0; month < 11; month++) {
int newdays;
newdays = days - month_days(month, year);
if (newdays < 0)
break;
days = newdays;
}
tm->tm_mon = month;
tm->tm_mday = days + 1;
tm->tm_hour = time / 3600;
time -= tm->tm_hour * 3600;
tm->tm_min = time / 60;
tm->tm_sec = time - tm->tm_min * 60;
}
EXPORT_SYMBOL(rtc_time_to_tm);
/*
* Does the rtc_time represent a valid date/time?
*/
int rtc_valid_tm(struct rtc_time *tm)
{
if (tm->tm_year < 70 ||
tm->tm_mon >= 12 ||
tm->tm_mday < 1 ||
tm->tm_mday > month_days(tm->tm_mon, tm->tm_year + 1900) ||
tm->tm_hour >= 24 ||
tm->tm_min >= 60 ||
tm->tm_sec >= 60)
return -EINVAL;
return 0;
}
EXPORT_SYMBOL(rtc_valid_tm);
/*
* Convert Gregorian date to seconds since 01-01-1970 00:00:00.
*/
int rtc_tm_to_time(struct rtc_time *tm, unsigned long *time)
{
*time = mktime(tm->tm_year + 1900, tm->tm_mon + 1, tm->tm_mday,
tm->tm_hour, tm->tm_min, tm->tm_sec);
return 0;
}
EXPORT_SYMBOL(rtc_tm_to_time);
/*
* Calculate the next alarm time given the requested alarm time mask
* and the current time.
*
* FIXME: for now, we just copy the alarm time because we're lazy (and
* is therefore buggy - setting a 10am alarm at 8pm will not result in
* the alarm triggering.)
*/
void rtc_next_alarm_time(struct rtc_time *next, struct rtc_time *now, struct rtc_time *alrm)
{
next->tm_year = now->tm_year;
next->tm_mon = now->tm_mon;
next->tm_mday = now->tm_mday;
next->tm_hour = alrm->tm_hour;
next->tm_min = alrm->tm_min;
next->tm_sec = alrm->tm_sec;
}
static inline int rtc_read_time(struct rtc_ops *ops, struct rtc_time *tm)
{
memset(tm, 0, sizeof(struct rtc_time));
return ops->read_time(tm);
}
static inline int rtc_set_time(struct rtc_ops *ops, struct rtc_time *tm)
{
int ret;
ret = rtc_valid_tm(tm);
if (ret == 0)
ret = ops->set_time(tm);
return ret;
}
static inline int rtc_read_alarm(struct rtc_ops *ops, struct rtc_wkalrm *alrm)
{
int ret = -EINVAL;
if (ops->read_alarm) {
memset(alrm, 0, sizeof(struct rtc_wkalrm));
ret = ops->read_alarm(alrm);
}
return ret;
}
static inline int rtc_set_alarm(struct rtc_ops *ops, struct rtc_wkalrm *alrm)
{
int ret = -EINVAL;
if (ops->set_alarm)
ret = ops->set_alarm(alrm);
return ret;
}
void rtc_update(unsigned long num, unsigned long events)
{
spin_lock(&rtc_lock);
rtc_irq_data = (rtc_irq_data + (num << 8)) | events;
spin_unlock(&rtc_lock);
wake_up_interruptible(&rtc_wait);
kill_fasync(&rtc_async_queue, SIGIO, POLL_IN);
}
EXPORT_SYMBOL(rtc_update);
static ssize_t
rtc_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
{
DECLARE_WAITQUEUE(wait, current);
unsigned long data;
ssize_t ret;
if (count < sizeof(unsigned long))
return -EINVAL;
add_wait_queue(&rtc_wait, &wait);
do {
__set_current_state(TASK_INTERRUPTIBLE);
spin_lock_irq(&rtc_lock);
data = rtc_irq_data;
rtc_irq_data = 0;
spin_unlock_irq(&rtc_lock);
if (data != 0) {
ret = 0;
break;
}
if (file->f_flags & O_NONBLOCK) {
ret = -EAGAIN;
break;
}
if (signal_pending(current)) {
ret = -ERESTARTSYS;
break;
}
schedule();
} while (1);
set_current_state(TASK_RUNNING);
remove_wait_queue(&rtc_wait, &wait);
if (ret == 0) {
ret = put_user(data, (unsigned long __user *)buf);
if (ret == 0)
ret = sizeof(unsigned long);
}
return ret;
}
static unsigned int rtc_poll(struct file *file, poll_table *wait)
{
unsigned long data;
poll_wait(file, &rtc_wait, wait);
spin_lock_irq(&rtc_lock);
data = rtc_irq_data;
spin_unlock_irq(&rtc_lock);
return data != 0 ? POLLIN | POLLRDNORM : 0;
}
static int rtc_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
unsigned long arg)
{
struct rtc_ops *ops = file->private_data;
struct rtc_time tm;
struct rtc_wkalrm alrm;
void __user *uarg = (void __user *)arg;
int ret = -EINVAL;
switch (cmd) {
case RTC_ALM_READ:
ret = rtc_read_alarm(ops, &alrm);
if (ret)
break;
ret = copy_to_user(uarg, &alrm.time, sizeof(tm));
if (ret)
ret = -EFAULT;
break;
case RTC_ALM_SET:
ret = copy_from_user(&alrm.time, uarg, sizeof(tm));
if (ret) {
ret = -EFAULT;
break;
}
alrm.enabled = 0;
alrm.pending = 0;
alrm.time.tm_mday = -1;
alrm.time.tm_mon = -1;
alrm.time.tm_year = -1;
alrm.time.tm_wday = -1;
alrm.time.tm_yday = -1;
alrm.time.tm_isdst = -1;
ret = rtc_set_alarm(ops, &alrm);
break;
case RTC_RD_TIME:
ret = rtc_read_time(ops, &tm);
if (ret)
break;
ret = copy_to_user(uarg, &tm, sizeof(tm));
if (ret)
ret = -EFAULT;
break;
case RTC_SET_TIME:
if (!capable(CAP_SYS_TIME)) {
ret = -EACCES;
break;
}
ret = copy_from_user(&tm, uarg, sizeof(tm));
if (ret) {
ret = -EFAULT;
break;
}
ret = rtc_set_time(ops, &tm);
break;
case RTC_EPOCH_SET:
#ifndef rtc_epoch
/*
* There were no RTC clocks before 1900.
*/
if (arg < 1900) {
ret = -EINVAL;
break;
}
if (!capable(CAP_SYS_TIME)) {
ret = -EACCES;
break;
}
rtc_epoch = arg;
ret = 0;
#endif
break;
case RTC_EPOCH_READ:
ret = put_user(rtc_epoch, (unsigned long __user *)uarg);
break;
case RTC_WKALM_SET:
ret = copy_from_user(&alrm, uarg, sizeof(alrm));
if (ret) {
ret = -EFAULT;
break;
}
ret = rtc_set_alarm(ops, &alrm);
break;
case RTC_WKALM_RD:
ret = rtc_read_alarm(ops, &alrm);
if (ret)
break;
ret = copy_to_user(uarg, &alrm, sizeof(alrm));
if (ret)
ret = -EFAULT;
break;
default:
if (ops->ioctl)
ret = ops->ioctl(cmd, arg);
break;
}
return ret;
}
static int rtc_open(struct inode *inode, struct file *file)
{
int ret;
down(&rtc_sem);
if (rtc_inuse) {
ret = -EBUSY;
} else if (!rtc_ops || !try_module_get(rtc_ops->owner)) {
ret = -ENODEV;
} else {
file->private_data = rtc_ops;
ret = rtc_ops->open ? rtc_ops->open() : 0;
if (ret == 0) {
spin_lock_irq(&rtc_lock);
rtc_irq_data = 0;
spin_unlock_irq(&rtc_lock);
rtc_inuse = 1;
}
}
up(&rtc_sem);
return ret;
}
static int rtc_release(struct inode *inode, struct file *file)
{
struct rtc_ops *ops = file->private_data;
if (ops->release)
ops->release();
spin_lock_irq(&rtc_lock);
rtc_irq_data = 0;
spin_unlock_irq(&rtc_lock);
module_put(rtc_ops->owner);
rtc_inuse = 0;
return 0;
}
static int rtc_fasync(int fd, struct file *file, int on)
{
return fasync_helper(fd, file, on, &rtc_async_queue);
}
static struct file_operations rtc_fops = {
.owner = THIS_MODULE,
.llseek = no_llseek,
.read = rtc_read,
.poll = rtc_poll,
.ioctl = rtc_ioctl,
.open = rtc_open,
.release = rtc_release,
.fasync = rtc_fasync,
};
static struct miscdevice rtc_miscdev = {
.minor = RTC_MINOR,
.name = "rtc",
.fops = &rtc_fops,
};
static int rtc_read_proc(char *page, char **start, off_t off, int count, int *eof, void *data)
{
struct rtc_ops *ops = data;
struct rtc_wkalrm alrm;
struct rtc_time tm;
char *p = page;
if (rtc_read_time(ops, &tm) == 0) {
p += sprintf(p,
"rtc_time\t: %02d:%02d:%02d\n"
"rtc_date\t: %04d-%02d-%02d\n"
"rtc_epoch\t: %04lu\n",
tm.tm_hour, tm.tm_min, tm.tm_sec,
tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday,
rtc_epoch);
}
if (rtc_read_alarm(ops, &alrm) == 0) {
p += sprintf(p, "alrm_time\t: ");
if ((unsigned int)alrm.time.tm_hour <= 24)
p += sprintf(p, "%02d:", alrm.time.tm_hour);
else
p += sprintf(p, "**:");
if ((unsigned int)alrm.time.tm_min <= 59)
p += sprintf(p, "%02d:", alrm.time.tm_min);
else
p += sprintf(p, "**:");
if ((unsigned int)alrm.time.tm_sec <= 59)
p += sprintf(p, "%02d\n", alrm.time.tm_sec);
else
p += sprintf(p, "**\n");
p += sprintf(p, "alrm_date\t: ");
if ((unsigned int)alrm.time.tm_year <= 200)
p += sprintf(p, "%04d-", alrm.time.tm_year + 1900);
else
p += sprintf(p, "****-");
if ((unsigned int)alrm.time.tm_mon <= 11)
p += sprintf(p, "%02d-", alrm.time.tm_mon + 1);
else
p += sprintf(p, "**-");
if ((unsigned int)alrm.time.tm_mday <= 31)
p += sprintf(p, "%02d\n", alrm.time.tm_mday);
else
p += sprintf(p, "**\n");
p += sprintf(p, "alrm_wakeup\t: %s\n",
alrm.enabled ? "yes" : "no");
p += sprintf(p, "alrm_pending\t: %s\n",
alrm.pending ? "yes" : "no");
}
if (ops->proc)
p += ops->proc(p);
return p - page;
}
int register_rtc(struct rtc_ops *ops)
{
int ret = -EBUSY;
down(&rtc_sem);
if (rtc_ops == NULL) {
rtc_ops = ops;
ret = misc_register(&rtc_miscdev);
if (ret == 0)
create_proc_read_entry("driver/rtc", 0, NULL,
rtc_read_proc, ops);
}
up(&rtc_sem);
return ret;
}
EXPORT_SYMBOL(register_rtc);
void unregister_rtc(struct rtc_ops *rtc)
{
down(&rtc_sem);
if (rtc == rtc_ops) {
remove_proc_entry("driver/rtc", NULL);
misc_deregister(&rtc_miscdev);
rtc_ops = NULL;
}
up(&rtc_sem);
}
EXPORT_SYMBOL(unregister_rtc);
