| /* |
| * 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/capability.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); |