--- /dev/null
+/*
+ * TI OMAP Real Time Clock interface for Linux
+ *
+ * Copyright (C) 2003 MontaVista Software, Inc.
+ * Author: George G. Davis <gdavis@mvista.com> or <source@mvista.com>
+ *
+ * Initially based on linux-2.4.20/drivers/char/rtc.c
+ * Copyright (C) 1996 Paul Gortmaker
+ *
+ * This driver allows use of the real time clock (built into
+ * nearly all computers) from user space. It exports the /dev/rtc
+ * interface supporting various ioctl() and also the
+ * /proc/driver/rtc pseudo-file for status information.
+ *
+ * The ioctls can be used to set the interrupt behaviour from the
+ * RTC via IRQs. Then the /dev/rtc interface can be used to make
+ * use of RTC interrupts, be they time update or alarm based.
+ *
+ * The /dev/rtc interface will block on reads until an interrupt
+ * has been received. If a RTC interrupt has already happened,
+ * it will output an unsigned long and then block. The output value
+ * contains the interrupt status in the low byte and the number of
+ * interrupts since the last read in the remaining high bytes. The
+ * /dev/rtc interface can also be used with the select(2) call.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ * Based on other minimal char device drivers, like Alan's
+ * watchdog, Ted's random, etc. etc.
+ *
+ * Change Log :
+ * v1.0 <gdavis@mvista.com> Initial version based on rtc.c v1.10e
+ * <ramakrishnan@india.ti.com> Added support for 2.6 kernel,
+ * - changed the return value of the interrupt handler
+ */
+
+#define RTC_VERSION "1.0"
+
+/*
+ * Note that *all* calls to CMOS_READ and CMOS_WRITE are done with
+ * interrupts disabled.
+ * REVISIT: Elaborate on OMAP1510 TRM 15uS BUSY access rule.
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/miscdevice.h>
+#include <linux/ioport.h>
+#include <linux/fcntl.h>
+#include <linux/init.h>
+#include <linux/poll.h>
+#include <linux/proc_fs.h>
+#include <linux/spinlock.h>
+#include <linux/rtc.h>
+
+#include <linux/interrupt.h>
+#include <linux/rtc.h>
+
+#include <asm/io.h>
+#include <asm/uaccess.h>
+#include <asm/system.h>
+#include <asm/hardware.h>
+#include <asm/irq.h>
+#include "omap-rtc.h"
+
+extern spinlock_t rtc_lock;
+
+
+/* OMAP RTC register access macros: */
+
+#define CMOS_READ(addr) omap_readb(addr)
+#define CMOS_WRITE(val, addr) omap_writeb(val, addr)
+
+
+/* Local BCD/BIN conversion macros: */
+#ifdef BCD_TO_BIN
+#undef BCD_TO_BIN
+#endif
+#define BCD_TO_BIN(val) ((val)=((val)&15) + ((val)>>4)*10)
+
+#ifdef BIN_TO_BCD
+#undef BIN_TO_BCD
+#endif
+#define BIN_TO_BCD(val) ((val)=(((val)/10)<<4) + (val)%10)
+
+
+/*
+ * We sponge a minor off of the misc major. No need slurping
+ * up another valuable major dev number for this. If you add
+ * an ioctl, make sure you don't conflict with SPARC's RTC
+ * ioctls.
+ */
+
+static struct fasync_struct *rtc_async_queue;
+
+static DECLARE_WAIT_QUEUE_HEAD(rtc_wait);
+
+static ssize_t rtc_read(struct file *file, char *buf,
+ size_t count, loff_t *ppos);
+
+static int rtc_ioctl(struct inode *inode, struct file *file,
+ unsigned int cmd, unsigned long arg);
+
+static unsigned int rtc_poll(struct file *file, poll_table *wait);
+
+static void get_rtc_time (struct rtc_time *rtc_tm);
+static void get_rtc_alm_time (struct rtc_time *alm_tm);
+
+static void set_rtc_irq_bit(unsigned char bit);
+static void mask_rtc_irq_bit(unsigned char bit);
+
+static inline unsigned char rtc_is_updating(void);
+
+static int rtc_read_proc(char *page, char **start, off_t off,
+ int count, int *eof, void *data);
+
+/*
+ * Bits in rtc_status. (7 bits of room for future expansion)
+ */
+
+#define RTC_IS_OPEN 0x01 /* means /dev/rtc is in use */
+
+/*
+ * REVISIT: fix this comment:
+ * rtc_status is never changed by rtc_interrupt, and ioctl/open/close is
+ * protected by the big kernel lock.
+ */
+static unsigned long rtc_status = 0; /* bitmapped status byte. */
+static unsigned long rtc_irq_data = 0; /* our output to the world */
+
+/*
+ * If this driver ever becomes modularised, it will be really nice
+ * to make the epoch retain its value across module reload...
+ */
+
+static unsigned long epoch = 1900; /* year corresponding to 0x00 */
+
+static const unsigned char days_in_mo[] =
+{0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
+
+/*
+ * A very tiny interrupt handler. It runs with SA_INTERRUPT set.
+ */
+
+static irqreturn_t rtc_interrupt(int irq, void *dev_id, struct pt_regs *regs)
+{
+ /*
+ * Either an alarm interrupt or update complete interrupt.
+ * We store the status in the low byte and the number of
+ * interrupts received since the last read in the remainder
+ * of rtc_irq_data.
+ */
+
+ spin_lock (&rtc_lock);
+
+ rtc_irq_data += 0x100;
+ rtc_irq_data &= ~0xff;
+ rtc_irq_data |= CMOS_READ(OMAP_RTC_STATUS_REG);
+
+ if (rtc_irq_data & OMAP_RTC_STATUS_ALARM)
+ CMOS_WRITE(OMAP_RTC_STATUS_ALARM, OMAP_RTC_STATUS_REG);
+
+ spin_unlock (&rtc_lock);
+
+ /* Now do the rest of the actions */
+ wake_up_interruptible(&rtc_wait);
+
+ kill_fasync (&rtc_async_queue, SIGIO, POLL_IN);
+ return IRQ_HANDLED;
+}
+
+/*
+ * Now all the various file operations that we export.
+ */
+
+static ssize_t rtc_read(struct file *file, char *buf,
+ size_t count, loff_t *ppos)
+{
+ DECLARE_WAITQUEUE(wait, current);
+ unsigned long data;
+ ssize_t retval;
+
+ if (count < sizeof(unsigned long))
+ return -EINVAL;
+
+ add_wait_queue(&rtc_wait, &wait);
+ set_current_state(TASK_INTERRUPTIBLE);
+
+ for (;;) {
+ spin_lock_irq (&rtc_lock);
+ data = rtc_irq_data;
+ if (data != 0) {
+ rtc_irq_data = 0;
+ break;
+ }
+ spin_unlock_irq (&rtc_lock);
+
+ if (file->f_flags & O_NONBLOCK) {
+ retval = -EAGAIN;
+ goto out;
+ }
+ if (signal_pending(current)) {
+ retval = -ERESTARTSYS;
+ goto out;
+ }
+ schedule();
+ }
+
+ spin_unlock_irq (&rtc_lock);
+ retval = put_user(data, (unsigned long *)buf);
+ if (!retval)
+ retval = sizeof(unsigned long);
+ out:
+ set_current_state(TASK_RUNNING);
+ remove_wait_queue(&rtc_wait, &wait);
+
+ return retval;
+}
+
+static int rtc_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ struct rtc_time wtime;
+
+ switch (cmd) {
+ case RTC_AIE_OFF: /* Mask alarm int. enab. bit */
+ {
+ mask_rtc_irq_bit(OMAP_RTC_INTERRUPTS_IT_ALARM);
+ return 0;
+ }
+ case RTC_AIE_ON: /* Allow alarm interrupts. */
+ {
+ set_rtc_irq_bit(OMAP_RTC_INTERRUPTS_IT_ALARM);
+ return 0;
+ }
+ case RTC_UIE_OFF: /* Mask ints from RTC updates. */
+ {
+ mask_rtc_irq_bit(OMAP_RTC_INTERRUPTS_IT_TIMER);
+ return 0;
+ }
+ case RTC_UIE_ON: /* Allow ints for RTC updates. */
+ {
+ set_rtc_irq_bit(OMAP_RTC_INTERRUPTS_IT_TIMER);
+ return 0;
+ }
+ case RTC_ALM_READ: /* Read the present alarm time */
+ {
+ /*
+ * This returns a struct rtc_time. Reading >= 0xc0
+ * means "don't care" or "match all". Only the tm_hour,
+ * tm_min, and tm_sec values are filled in.
+ */
+ memset(&wtime, 0, sizeof(struct rtc_time));
+ get_rtc_alm_time(&wtime);
+ break;
+ }
+ case RTC_ALM_SET: /* Store a time into the alarm */
+ {
+ struct rtc_time alm_tm;
+ unsigned char mon, day, hrs, min, sec, leap_yr;
+ unsigned int yrs;
+
+ if (copy_from_user(&alm_tm, (struct rtc_time*)arg,
+ sizeof(struct rtc_time)))
+ return -EFAULT;
+
+ yrs = alm_tm.tm_year + 1900;
+ mon = alm_tm.tm_mon + 1;
+ day = alm_tm.tm_mday;
+ hrs = alm_tm.tm_hour;
+ min = alm_tm.tm_min;
+ sec = alm_tm.tm_sec;
+
+ if (yrs < 1970)
+ return -EINVAL;
+
+ leap_yr = ((!(yrs % 4) && (yrs % 100)) || !(yrs % 400));
+
+ if ((mon > 12) || (day == 0))
+ return -EINVAL;
+
+ if (day > (days_in_mo[mon] + ((mon == 2) && leap_yr)))
+ return -EINVAL;
+
+ if ((hrs >= 24) || (min >= 60) || (sec >= 60))
+ return -EINVAL;
+
+ if ((yrs -= epoch) > 255) /* They are unsigned */
+ return -EINVAL;
+
+ if (yrs > 169) {
+ return -EINVAL;
+ }
+
+ if (yrs >= 100)
+ yrs -= 100;
+
+ BIN_TO_BCD(sec);
+ BIN_TO_BCD(min);
+ BIN_TO_BCD(hrs);
+ BIN_TO_BCD(day);
+ BIN_TO_BCD(mon);
+ BIN_TO_BCD(yrs);
+
+ spin_lock_irq(&rtc_lock);
+ CMOS_WRITE(yrs, OMAP_RTC_ALARM_YEARS_REG);
+ CMOS_WRITE(mon, OMAP_RTC_ALARM_MONTHS_REG);
+ CMOS_WRITE(day, OMAP_RTC_ALARM_DAYS_REG);
+ CMOS_WRITE(hrs, OMAP_RTC_ALARM_HOURS_REG);
+ CMOS_WRITE(min, OMAP_RTC_ALARM_MINUTES_REG);
+ CMOS_WRITE(sec, OMAP_RTC_ALARM_SECONDS_REG);
+ spin_unlock_irq(&rtc_lock);
+
+ return 0;
+ }
+ case RTC_RD_TIME: /* Read the time/date from RTC */
+ {
+ memset(&wtime, 0, sizeof(struct rtc_time));
+ get_rtc_time(&wtime);
+ break;
+ }
+ case RTC_SET_TIME: /* Set the RTC */
+ {
+ struct rtc_time rtc_tm;
+ unsigned char mon, day, hrs, min, sec, leap_yr;
+ unsigned char save_control;
+ unsigned int yrs;
+
+ if (!capable(CAP_SYS_TIME))
+ return -EACCES;
+
+ if (copy_from_user(&rtc_tm, (struct rtc_time*)arg,
+ sizeof(struct rtc_time)))
+ return -EFAULT;
+
+ yrs = rtc_tm.tm_year + 1900;
+ mon = rtc_tm.tm_mon + 1; /* tm_mon starts at zero */
+ day = rtc_tm.tm_mday;
+ hrs = rtc_tm.tm_hour;
+ min = rtc_tm.tm_min;
+ sec = rtc_tm.tm_sec;
+
+ if (yrs < 1970)
+ return -EINVAL;
+
+ leap_yr = ((!(yrs % 4) && (yrs % 100)) || !(yrs % 400));
+
+ if ((mon > 12) || (day == 0))
+ return -EINVAL;
+
+ if (day > (days_in_mo[mon] + ((mon == 2) && leap_yr)))
+ return -EINVAL;
+
+ if ((hrs >= 24) || (min >= 60) || (sec >= 60))
+ return -EINVAL;
+
+ if ((yrs -= epoch) > 255) /* They are unsigned */
+ return -EINVAL;
+
+ if (yrs > 169) {
+ return -EINVAL;
+ }
+
+ if (yrs >= 100)
+ yrs -= 100;
+
+ BIN_TO_BCD(sec);
+ BIN_TO_BCD(min);
+ BIN_TO_BCD(hrs);
+ BIN_TO_BCD(day);
+ BIN_TO_BCD(mon);
+ BIN_TO_BCD(yrs);
+
+ spin_lock_irq(&rtc_lock);
+ save_control = CMOS_READ(OMAP_RTC_CTRL_REG);
+ CMOS_WRITE((save_control & ~OMAP_RTC_CTRL_STOP),
+ OMAP_RTC_CTRL_REG);
+ CMOS_WRITE(yrs, OMAP_RTC_YEARS_REG);
+ CMOS_WRITE(mon, OMAP_RTC_MONTHS_REG);
+ CMOS_WRITE(day, OMAP_RTC_DAYS_REG);
+ CMOS_WRITE(hrs, OMAP_RTC_HOURS_REG);
+ CMOS_WRITE(min, OMAP_RTC_MINUTES_REG);
+ CMOS_WRITE(sec, OMAP_RTC_SECONDS_REG);
+ CMOS_WRITE((save_control | OMAP_RTC_CTRL_STOP),
+ OMAP_RTC_CTRL_REG);
+ spin_unlock_irq(&rtc_lock);
+
+ return 0;
+ }
+ case RTC_EPOCH_READ: /* Read the epoch. */
+ {
+ return put_user (epoch, (unsigned long *)arg);
+ }
+ case RTC_EPOCH_SET: /* Set the epoch. */
+ {
+ /*
+ * There were no RTC clocks before 1900.
+ */
+ if (arg < 1900)
+ return -EINVAL;
+
+ if (!capable(CAP_SYS_TIME))
+ return -EACCES;
+
+ epoch = arg;
+ return 0;
+ }
+ default:
+#if !defined(CONFIG_ARCH_OMAP)
+ return -ENOTTY;
+#else
+ return -EINVAL;
+#endif
+ }
+ return copy_to_user((void *)arg, &wtime, sizeof wtime) ? -EFAULT : 0;
+}
+
+/*
+ * We enforce only one user at a time here with the open/close.
+ * Also clear the previous interrupt data on an open, and clean
+ * up things on a close.
+ */
+
+/* We use rtc_lock to protect against concurrent opens. So the BKL is not
+ * needed here. Or anywhere else in this driver. */
+static int rtc_open(struct inode *inode, struct file *file)
+{
+ spin_lock_irq (&rtc_lock);
+
+ if(rtc_status & RTC_IS_OPEN)
+ goto out_busy;
+
+ rtc_status |= RTC_IS_OPEN;
+
+ rtc_irq_data = 0;
+ spin_unlock_irq (&rtc_lock);
+ return 0;
+
+out_busy:
+ spin_unlock_irq (&rtc_lock);
+ return -EBUSY;
+}
+
+static int rtc_fasync (int fd, struct file *filp, int on)
+
+{
+ return fasync_helper (fd, filp, on, &rtc_async_queue);
+}
+
+static int rtc_release(struct inode *inode, struct file *file)
+{
+ unsigned char tmp;
+
+ /*
+ * Turn off all interrupts once the device is no longer
+ * in use, and clear the data.
+ */
+
+ spin_lock_irq(&rtc_lock);
+ tmp = CMOS_READ(OMAP_RTC_INTERRUPTS_REG);
+ tmp &= ~OMAP_RTC_INTERRUPTS_IT_ALARM;
+ tmp &= ~OMAP_RTC_INTERRUPTS_IT_TIMER;
+ CMOS_WRITE(tmp, OMAP_RTC_INTERRUPTS_REG);
+ spin_unlock_irq(&rtc_lock);
+
+ if (file->f_flags & FASYNC) {
+ rtc_fasync (-1, file, 0);
+ }
+
+ spin_lock_irq (&rtc_lock);
+ rtc_irq_data = 0;
+ spin_unlock_irq (&rtc_lock);
+
+ /* No need for locking -- nobody else can do anything until this rmw
+ * is committed, and we don't implement timer support in omap-rtc.
+ */
+ rtc_status &= ~RTC_IS_OPEN;
+ return 0;
+}
+
+/* Called without the kernel lock - fine */
+static unsigned int rtc_poll(struct file *file, poll_table *wait)
+{
+ unsigned long l;
+
+ poll_wait(file, &rtc_wait, wait);
+
+ spin_lock_irq (&rtc_lock);
+ l = rtc_irq_data;
+ spin_unlock_irq (&rtc_lock);
+
+ if (l != 0)
+ return POLLIN | POLLRDNORM;
+ return 0;
+}
+
+/*
+ * The various file operations we support.
+ */
+
+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_dev=
+{
+ RTC_MINOR,
+ "rtc",
+ &rtc_fops
+};
+
+static int __init rtc_init(void)
+{
+ if (!request_region(OMAP_RTC_VIRT_BASE, OMAP_RTC_SIZE,
+ rtc_dev.name)) {
+ printk(KERN_ERR "%s: RTC I/O port %d is not free.\n",
+ rtc_dev.name, OMAP_RTC_VIRT_BASE);
+ return -EIO;
+ }
+
+ if (CMOS_READ(OMAP_RTC_STATUS_REG) & OMAP_RTC_STATUS_POWER_UP) {
+ printk(KERN_WARNING "%s: RTC power up reset detected.\n",
+ rtc_dev.name);
+ /* Clear OMAP_RTC_STATUS_POWER_UP */
+ CMOS_WRITE(OMAP_RTC_STATUS_POWER_UP, OMAP_RTC_STATUS_REG);
+ }
+
+ if (CMOS_READ(OMAP_RTC_STATUS_REG) & OMAP_RTC_STATUS_ALARM) {
+ printk(KERN_WARNING "%s: Clearing RTC ALARM interrupt.\n",
+ rtc_dev.name);
+ /* Clear OMAP_RTC_STATUS_ALARM */
+ CMOS_WRITE(OMAP_RTC_STATUS_ALARM, OMAP_RTC_STATUS_REG);
+ }
+
+ if (!(CMOS_READ(OMAP_RTC_CTRL_REG) & OMAP_RTC_CTRL_STOP)) {
+ printk(KERN_INFO "%s: Enabling RTC.\n", rtc_dev.name);
+ CMOS_WRITE(OMAP_RTC_CTRL_STOP, OMAP_RTC_CTRL_REG);
+ }
+
+ if (request_irq(INT_RTC_TIMER, rtc_interrupt, SA_INTERRUPT,
+ rtc_dev.name, NULL)) {
+ printk(KERN_ERR "%s: RTC timer interrupt IRQ%d is not free.\n",
+ rtc_dev.name, INT_RTC_TIMER);
+ release_region(OMAP_RTC_VIRT_BASE, OMAP_RTC_SIZE);
+ return -EIO;
+ }
+
+ if (request_irq(INT_RTC_ALARM, rtc_interrupt, SA_INTERRUPT,
+ "omap-rtc alarm", NULL)) {
+ printk(KERN_ERR "%s: RTC alarm interrupt IRQ%d is not free.\n",
+ rtc_dev.name, INT_RTC_ALARM);
+ release_region(OMAP_RTC_VIRT_BASE, OMAP_RTC_SIZE);
+ return -EIO;
+ }
+
+ spin_lock_init(&rtc_lock);
+ misc_register(&rtc_dev);
+ create_proc_read_entry ("driver/rtc", 0, 0, rtc_read_proc, NULL);
+
+ printk(KERN_INFO "Real Time Clock Driver v" RTC_VERSION "\n");
+
+ return 0;
+}
+
+static void __exit rtc_exit (void)
+{
+ free_irq (INT_RTC_TIMER, NULL);
+ free_irq (INT_RTC_ALARM, NULL);
+
+ remove_proc_entry ("driver/rtc", NULL);
+ misc_deregister(&rtc_dev);
+
+ release_region (OMAP_RTC_VIRT_BASE, OMAP_RTC_SIZE);
+}
+
+/*
+ * Info exported via "/proc/driver/rtc".
+ */
+
+static int rtc_proc_output (char *buf)
+{
+#define YN(value) ((value) ? "yes" : "no")
+#define NY(value) ((value) ? "no" : "yes")
+ char *p;
+ struct rtc_time tm;
+
+ p = buf;
+
+ get_rtc_time(&tm);
+
+ /*
+ * There is no way to tell if the luser has the RTC set for local
+ * time or for Universal Standard Time (GMT). Probably local though.
+ */
+ 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, epoch);
+
+ get_rtc_alm_time(&tm);
+
+ /*
+ * We implicitly assume 24hr mode here. Alarm values >= 0xc0 will
+ * match any value for that particular field. Values that are
+ * greater than a valid time, but less than 0xc0 shouldn't appear.
+ */
+ p += sprintf(p,
+ "alarm_time\t: %02d:%02d:%02d\n"
+ "alarm_date\t: %04d-%02d-%02d\n",
+ tm.tm_hour, tm.tm_min, tm.tm_sec,
+ tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday);
+
+ p += sprintf(p,
+ "BCD\t\t: %s\n"
+ "24hr\t\t: %s\n"
+ "alarm_IRQ\t: %s\n"
+ "update_IRQ\t: %s\n"
+ "update_rate\t: %ud\n",
+ YN(1),
+ YN(1),
+ YN(CMOS_READ(OMAP_RTC_INTERRUPTS_REG) &
+ OMAP_RTC_INTERRUPTS_IT_ALARM),
+ YN(CMOS_READ(OMAP_RTC_INTERRUPTS_REG) &
+ OMAP_RTC_INTERRUPTS_IT_TIMER),
+ CMOS_READ(OMAP_RTC_INTERRUPTS_REG) & 3 /* REVISIT */);
+
+ return p - buf;
+#undef YN
+#undef NY
+}
+
+static int rtc_read_proc(char *page, char **start, off_t off,
+ int count, int *eof, void *data)
+{
+ int len = rtc_proc_output (page);
+ if (len <= off+count) *eof = 1;
+ *start = page + off;
+ len -= off;
+ if (len>count) len = count;
+ if (len<0) len = 0;
+ return len;
+}
+
+/*
+ * Returns true if a clock update is in progress
+ */
+/* FIXME shouldn't this be above rtc_init to make it fully inlined? */
+static inline unsigned char rtc_is_updating(void)
+{
+ unsigned char uip;
+
+ spin_lock_irq(&rtc_lock);
+ uip = (CMOS_READ(OMAP_RTC_STATUS_REG) & OMAP_RTC_STATUS_BUSY);
+ spin_unlock_irq(&rtc_lock);
+ return uip;
+}
+
+static void get_rtc_time(struct rtc_time *rtc_tm)
+{
+ unsigned char ctrl;
+
+ /* REVISIT: Fix this comment!!!
+ * read RTC once any update in progress is done. The update
+ * can take just over 2ms. We wait 10 to 20ms. There is no need to
+ * to poll-wait (up to 1s - eeccch) for the falling edge of OMAP_RTC_STATUS_BUSY.
+ * If you need to know *exactly* when a second has started, enable
+ * periodic update complete interrupts, (via ioctl) and then
+ * immediately read /dev/rtc which will block until you get the IRQ.
+ * Once the read clears, read the RTC time (again via ioctl). Easy.
+ */
+
+#if 0 /* REVISIT: This need to do as the TRM says. */
+ unsigned long uip_watchdog = jiffies;
+ if (rtc_is_updating() != 0)
+ while (jiffies - uip_watchdog < 2*HZ/100) {
+ barrier();
+ cpu_relax();
+ }
+#endif
+
+ /*
+ * Only the values that we read from the RTC are set. We leave
+ * tm_wday, tm_yday and tm_isdst untouched. Even though the
+ * RTC has RTC_DAY_OF_WEEK, we ignore it, as it is only updated
+ * by the RTC when initially set to a non-zero value.
+ */
+ spin_lock_irq(&rtc_lock);
+ rtc_tm->tm_sec = CMOS_READ(OMAP_RTC_SECONDS_REG);
+ rtc_tm->tm_min = CMOS_READ(OMAP_RTC_MINUTES_REG);
+ rtc_tm->tm_hour = CMOS_READ(OMAP_RTC_HOURS_REG);
+ rtc_tm->tm_mday = CMOS_READ(OMAP_RTC_DAYS_REG);
+ rtc_tm->tm_mon = CMOS_READ(OMAP_RTC_MONTHS_REG);
+ rtc_tm->tm_year = CMOS_READ(OMAP_RTC_YEARS_REG);
+ ctrl = CMOS_READ(OMAP_RTC_CTRL_REG);
+ spin_unlock_irq(&rtc_lock);
+
+ BCD_TO_BIN(rtc_tm->tm_sec);
+ BCD_TO_BIN(rtc_tm->tm_min);
+ BCD_TO_BIN(rtc_tm->tm_hour);
+ BCD_TO_BIN(rtc_tm->tm_mday);
+ BCD_TO_BIN(rtc_tm->tm_mon);
+ BCD_TO_BIN(rtc_tm->tm_year);
+
+ /*
+ * Account for differences between how the RTC uses the values
+ * and how they are defined in a struct rtc_time;
+ */
+ if ((rtc_tm->tm_year += (epoch - 1900)) <= 69)
+ rtc_tm->tm_year += 100;
+
+ rtc_tm->tm_mon--;
+}
+
+static void get_rtc_alm_time(struct rtc_time *alm_tm)
+{
+ unsigned char ctrl;
+
+ spin_lock_irq(&rtc_lock);
+ alm_tm->tm_sec = CMOS_READ(OMAP_RTC_ALARM_SECONDS_REG);
+ alm_tm->tm_min = CMOS_READ(OMAP_RTC_ALARM_MINUTES_REG);
+ alm_tm->tm_hour = CMOS_READ(OMAP_RTC_ALARM_HOURS_REG);
+ alm_tm->tm_mday = CMOS_READ(OMAP_RTC_ALARM_DAYS_REG);
+ alm_tm->tm_mon = CMOS_READ(OMAP_RTC_ALARM_MONTHS_REG);
+ alm_tm->tm_year = CMOS_READ(OMAP_RTC_ALARM_YEARS_REG);
+ ctrl = CMOS_READ(OMAP_RTC_CTRL_REG);
+ spin_unlock_irq(&rtc_lock);
+
+ BCD_TO_BIN(alm_tm->tm_sec);
+ BCD_TO_BIN(alm_tm->tm_min);
+ BCD_TO_BIN(alm_tm->tm_hour);
+ BCD_TO_BIN(alm_tm->tm_mday);
+ BCD_TO_BIN(alm_tm->tm_mon);
+ BCD_TO_BIN(alm_tm->tm_year);
+
+ /*
+ * Account for differences between how the RTC uses the values
+ * and how they are defined in a struct rtc_time;
+ */
+ if ((alm_tm->tm_year += (epoch - 1900)) <= 69)
+ alm_tm->tm_year += 100;
+
+ alm_tm->tm_mon--;
+}
+
+/*
+ * Used to disable/enable UIE and AIE interrupts.
+ */
+
+static void mask_rtc_irq_bit(unsigned char bit)
+{
+ unsigned char val;
+
+ spin_lock_irq(&rtc_lock);
+ val = CMOS_READ(OMAP_RTC_INTERRUPTS_REG);
+ val &= ~bit;
+ CMOS_WRITE(val, OMAP_RTC_INTERRUPTS_REG);
+ rtc_irq_data = 0;
+ spin_unlock_irq(&rtc_lock);
+}
+
+static void set_rtc_irq_bit(unsigned char bit)
+{
+ unsigned char val;
+
+ spin_lock_irq(&rtc_lock);
+ val = CMOS_READ(OMAP_RTC_INTERRUPTS_REG);
+ val |= bit;
+ CMOS_WRITE(val, OMAP_RTC_INTERRUPTS_REG);
+ rtc_irq_data = 0;
+ spin_unlock_irq(&rtc_lock);
+}
+
+MODULE_AUTHOR("George G. Davis");
+MODULE_LICENSE("GPL");
+
+module_init(rtc_init);
+module_exit(rtc_exit);