diff options
Diffstat (limited to 'arch/arm/common/rtctime.c')
| -rw-r--r-- | arch/arm/common/rtctime.c | 506 |
1 files changed, 506 insertions, 0 deletions
diff --git a/arch/arm/common/rtctime.c b/arch/arm/common/rtctime.c new file mode 100644 index 00000000000..c397e71f938 --- /dev/null +++ b/arch/arm/common/rtctime.c @@ -0,0 +1,506 @@ +/* + * 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 void rtc_read_time(struct rtc_ops *ops, struct rtc_time *tm) +{ + memset(tm, 0, sizeof(struct rtc_time)); + 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)); + ops->read_alarm(alrm); + ret = 0; + } + 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: + rtc_read_time(ops, &tm); + 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; + + rtc_read_time(ops, &tm); + + 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); |