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Diffstat (limited to 'arch/arm/common/rtctime.c')
-rw-r--r--arch/arm/common/rtctime.c506
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);
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-15 05:19:46 +0000