+++ /dev/null
-/*
- * Real Time Clock interface for
- * - q40 and other m68k machines,
- * - HP PARISC machines
- * - PowerPC machines
- * emulate some RTC irq capabilities in software
- *
- * Copyright (C) 1999 Richard Zidlicky
- *
- * based on Paul Gortmaker's rtc.c device and
- * Sam Creasey Generic rtc driver
- *
- * 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 where
- * supported.
- *
- * 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.
- *
-
- * 1.01 fix for 2.3.X rz@linux-m68k.org
- * 1.02 merged with code from genrtc.c rz@linux-m68k.org
- * 1.03 make it more portable zippel@linux-m68k.org
- * 1.04 removed useless timer code rz@linux-m68k.org
- * 1.05 portable RTC_UIE emulation rz@linux-m68k.org
- * 1.06 set_rtc_time can return an error trini@kernel.crashing.org
- * 1.07 ported to HP PARISC (hppa) Helge Deller <deller@gmx.de>
- */
-
-#define RTC_VERSION "1.07"
-
-#include <linux/module.h>
-#include <linux/sched.h>
-#include <linux/errno.h>
-#include <linux/miscdevice.h>
-#include <linux/fcntl.h>
-
-#include <linux/rtc.h>
-#include <linux/init.h>
-#include <linux/poll.h>
-#include <linux/proc_fs.h>
-#include <linux/seq_file.h>
-#include <linux/mutex.h>
-#include <linux/workqueue.h>
-
-#include <asm/uaccess.h>
-#include <asm/rtc.h>
-
-/*
- * 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 DEFINE_MUTEX(gen_rtc_mutex);
-static DECLARE_WAIT_QUEUE_HEAD(gen_rtc_wait);
-
-/*
- * Bits in gen_rtc_status.
- */
-
-#define RTC_IS_OPEN 0x01 /* means /dev/rtc is in use */
-
-static unsigned char gen_rtc_status; /* bitmapped status byte. */
-static unsigned long gen_rtc_irq_data; /* our output to the world */
-
-/* months start at 0 now */
-static unsigned char days_in_mo[] =
-{31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
-
-static int irq_active;
-
-#ifdef CONFIG_GEN_RTC_X
-static struct work_struct genrtc_task;
-static struct timer_list timer_task;
-
-static unsigned int oldsecs;
-static int lostint;
-static unsigned long tt_exp;
-
-static void gen_rtc_timer(unsigned long data);
-
-static volatile int stask_active; /* schedule_work */
-static volatile int ttask_active; /* timer_task */
-static int stop_rtc_timers; /* don't requeue tasks */
-static DEFINE_SPINLOCK(gen_rtc_lock);
-
-static void gen_rtc_interrupt(unsigned long arg);
-
-/*
- * Routine to poll RTC seconds field for change as often as possible,
- * after first RTC_UIE use timer to reduce polling
- */
-static void genrtc_troutine(struct work_struct *work)
-{
- unsigned int tmp = get_rtc_ss();
-
- if (stop_rtc_timers) {
- stask_active = 0;
- return;
- }
-
- if (oldsecs != tmp){
- oldsecs = tmp;
-
- timer_task.function = gen_rtc_timer;
- timer_task.expires = jiffies + HZ - (HZ/10);
- tt_exp=timer_task.expires;
- ttask_active=1;
- stask_active=0;
- add_timer(&timer_task);
-
- gen_rtc_interrupt(0);
- } else if (schedule_work(&genrtc_task) == 0)
- stask_active = 0;
-}
-
-static void gen_rtc_timer(unsigned long data)
-{
- lostint = get_rtc_ss() - oldsecs ;
- if (lostint<0)
- lostint = 60 - lostint;
- if (time_after(jiffies, tt_exp))
- printk(KERN_INFO "genrtc: timer task delayed by %ld jiffies\n",
- jiffies-tt_exp);
- ttask_active=0;
- stask_active=1;
- if ((schedule_work(&genrtc_task) == 0))
- stask_active = 0;
-}
-
-/*
- * call gen_rtc_interrupt function to signal an RTC_UIE,
- * arg is unused.
- * Could be invoked either from a real interrupt handler or
- * from some routine that periodically (eg 100HZ) monitors
- * whether RTC_SECS changed
- */
-static void gen_rtc_interrupt(unsigned long arg)
-{
- /* 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. */
-
- gen_rtc_irq_data += 0x100;
- gen_rtc_irq_data &= ~0xff;
- gen_rtc_irq_data |= RTC_UIE;
-
- if (lostint){
- printk("genrtc: system delaying clock ticks?\n");
- /* increment count so that userspace knows something is wrong */
- gen_rtc_irq_data += ((lostint-1)<<8);
- lostint = 0;
- }
-
- wake_up_interruptible(&gen_rtc_wait);
-}
-
-/*
- * Now all the various file operations that we export.
- */
-static ssize_t gen_rtc_read(struct file *file, char __user *buf,
- size_t count, loff_t *ppos)
-{
- unsigned long data;
- ssize_t retval;
-
- if (count != sizeof (unsigned int) && count != sizeof (unsigned long))
- return -EINVAL;
-
- if (file->f_flags & O_NONBLOCK && !gen_rtc_irq_data)
- return -EAGAIN;
-
- retval = wait_event_interruptible(gen_rtc_wait,
- (data = xchg(&gen_rtc_irq_data, 0)));
- if (retval)
- goto out;
-
- /* first test allows optimizer to nuke this case for 32-bit machines */
- if (sizeof (int) != sizeof (long) && count == sizeof (unsigned int)) {
- unsigned int uidata = data;
- retval = put_user(uidata, (unsigned int __user *)buf) ?:
- sizeof(unsigned int);
- }
- else {
- retval = put_user(data, (unsigned long __user *)buf) ?:
- sizeof(unsigned long);
- }
-out:
- return retval;
-}
-
-static unsigned int gen_rtc_poll(struct file *file,
- struct poll_table_struct *wait)
-{
- poll_wait(file, &gen_rtc_wait, wait);
- if (gen_rtc_irq_data != 0)
- return POLLIN | POLLRDNORM;
- return 0;
-}
-
-#endif
-
-/*
- * Used to disable/enable interrupts, only RTC_UIE supported
- * We also clear out any old irq data after an ioctl() that
- * meddles with the interrupt enable/disable bits.
- */
-
-static inline void gen_clear_rtc_irq_bit(unsigned char bit)
-{
-#ifdef CONFIG_GEN_RTC_X
- stop_rtc_timers = 1;
- if (ttask_active){
- del_timer_sync(&timer_task);
- ttask_active = 0;
- }
- while (stask_active)
- schedule();
-
- spin_lock(&gen_rtc_lock);
- irq_active = 0;
- spin_unlock(&gen_rtc_lock);
-#endif
-}
-
-static inline int gen_set_rtc_irq_bit(unsigned char bit)
-{
-#ifdef CONFIG_GEN_RTC_X
- spin_lock(&gen_rtc_lock);
- if ( !irq_active ) {
- irq_active = 1;
- stop_rtc_timers = 0;
- lostint = 0;
- INIT_WORK(&genrtc_task, genrtc_troutine);
- oldsecs = get_rtc_ss();
- init_timer(&timer_task);
-
- stask_active = 1;
- if (schedule_work(&genrtc_task) == 0){
- stask_active = 0;
- }
- }
- spin_unlock(&gen_rtc_lock);
- gen_rtc_irq_data = 0;
- return 0;
-#else
- return -EINVAL;
-#endif
-}
-
-static int gen_rtc_ioctl(struct file *file,
- unsigned int cmd, unsigned long arg)
-{
- struct rtc_time wtime;
- struct rtc_pll_info pll;
- void __user *argp = (void __user *)arg;
-
- switch (cmd) {
-
- case RTC_PLL_GET:
- if (get_rtc_pll(&pll))
- return -EINVAL;
- else
- return copy_to_user(argp, &pll, sizeof pll) ? -EFAULT : 0;
-
- case RTC_PLL_SET:
- if (!capable(CAP_SYS_TIME))
- return -EACCES;
- if (copy_from_user(&pll, argp, sizeof(pll)))
- return -EFAULT;
- return set_rtc_pll(&pll);
-
- case RTC_UIE_OFF: /* disable ints from RTC updates. */
- gen_clear_rtc_irq_bit(RTC_UIE);
- return 0;
-
- case RTC_UIE_ON: /* enable ints for RTC updates. */
- return gen_set_rtc_irq_bit(RTC_UIE);
-
- case RTC_RD_TIME: /* Read the time/date from RTC */
- /* this doesn't get week-day, who cares */
- memset(&wtime, 0, sizeof(wtime));
- get_rtc_time(&wtime);
-
- return copy_to_user(argp, &wtime, sizeof(wtime)) ? -EFAULT : 0;
-
- case RTC_SET_TIME: /* Set the RTC */
- {
- int year;
- unsigned char leap_yr;
-
- if (!capable(CAP_SYS_TIME))
- return -EACCES;
-
- if (copy_from_user(&wtime, argp, sizeof(wtime)))
- return -EFAULT;
-
- year = wtime.tm_year + 1900;
- leap_yr = ((!(year % 4) && (year % 100)) ||
- !(year % 400));
-
- if ((wtime.tm_mon < 0 || wtime.tm_mon > 11) || (wtime.tm_mday < 1))
- return -EINVAL;
-
- if (wtime.tm_mday < 0 || wtime.tm_mday >
- (days_in_mo[wtime.tm_mon] + ((wtime.tm_mon == 1) && leap_yr)))
- return -EINVAL;
-
- if (wtime.tm_hour < 0 || wtime.tm_hour >= 24 ||
- wtime.tm_min < 0 || wtime.tm_min >= 60 ||
- wtime.tm_sec < 0 || wtime.tm_sec >= 60)
- return -EINVAL;
-
- return set_rtc_time(&wtime);
- }
- }
-
- return -EINVAL;
-}
-
-static long gen_rtc_unlocked_ioctl(struct file *file, unsigned int cmd,
- unsigned long arg)
-{
- int ret;
-
- mutex_lock(&gen_rtc_mutex);
- ret = gen_rtc_ioctl(file, cmd, arg);
- mutex_unlock(&gen_rtc_mutex);
-
- return ret;
-}
-
-/*
- * 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.
- */
-
-static int gen_rtc_open(struct inode *inode, struct file *file)
-{
- mutex_lock(&gen_rtc_mutex);
- if (gen_rtc_status & RTC_IS_OPEN) {
- mutex_unlock(&gen_rtc_mutex);
- return -EBUSY;
- }
-
- gen_rtc_status |= RTC_IS_OPEN;
- gen_rtc_irq_data = 0;
- irq_active = 0;
- mutex_unlock(&gen_rtc_mutex);
-
- return 0;
-}
-
-static int gen_rtc_release(struct inode *inode, struct file *file)
-{
- /*
- * Turn off all interrupts once the device is no longer
- * in use and clear the data.
- */
-
- gen_clear_rtc_irq_bit(RTC_PIE|RTC_AIE|RTC_UIE);
-
- gen_rtc_status &= ~RTC_IS_OPEN;
- return 0;
-}
-
-
-#ifdef CONFIG_PROC_FS
-
-/*
- * Info exported via "/proc/driver/rtc".
- */
-
-static int gen_rtc_proc_show(struct seq_file *m, void *v)
-{
- struct rtc_time tm;
- unsigned int flags;
- struct rtc_pll_info pll;
-
- flags = get_rtc_time(&tm);
-
- seq_printf(m,
- "rtc_time\t: %02d:%02d:%02d\n"
- "rtc_date\t: %04d-%02d-%02d\n"
- "rtc_epoch\t: %04u\n",
- tm.tm_hour, tm.tm_min, tm.tm_sec,
- tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday, 1900);
-
- tm.tm_hour = tm.tm_min = tm.tm_sec = 0;
-
- seq_puts(m, "alarm\t\t: ");
- if (tm.tm_hour <= 24)
- seq_printf(m, "%02d:", tm.tm_hour);
- else
- seq_puts(m, "**:");
-
- if (tm.tm_min <= 59)
- seq_printf(m, "%02d:", tm.tm_min);
- else
- seq_puts(m, "**:");
-
- if (tm.tm_sec <= 59)
- seq_printf(m, "%02d\n", tm.tm_sec);
- else
- seq_puts(m, "**\n");
-
- seq_printf(m,
- "DST_enable\t: %s\n"
- "BCD\t\t: %s\n"
- "24hr\t\t: %s\n"
- "square_wave\t: %s\n"
- "alarm_IRQ\t: %s\n"
- "update_IRQ\t: %s\n"
- "periodic_IRQ\t: %s\n"
- "periodic_freq\t: %ld\n"
- "batt_status\t: %s\n",
- (flags & RTC_DST_EN) ? "yes" : "no",
- (flags & RTC_DM_BINARY) ? "no" : "yes",
- (flags & RTC_24H) ? "yes" : "no",
- (flags & RTC_SQWE) ? "yes" : "no",
- (flags & RTC_AIE) ? "yes" : "no",
- irq_active ? "yes" : "no",
- (flags & RTC_PIE) ? "yes" : "no",
- 0L /* freq */,
- (flags & RTC_BATT_BAD) ? "bad" : "okay");
- if (!get_rtc_pll(&pll))
- seq_printf(m,
- "PLL adjustment\t: %d\n"
- "PLL max +ve adjustment\t: %d\n"
- "PLL max -ve adjustment\t: %d\n"
- "PLL +ve adjustment factor\t: %d\n"
- "PLL -ve adjustment factor\t: %d\n"
- "PLL frequency\t: %ld\n",
- pll.pll_value,
- pll.pll_max,
- pll.pll_min,
- pll.pll_posmult,
- pll.pll_negmult,
- pll.pll_clock);
- return 0;
-}
-
-static int gen_rtc_proc_open(struct inode *inode, struct file *file)
-{
- return single_open(file, gen_rtc_proc_show, NULL);
-}
-
-static const struct file_operations gen_rtc_proc_fops = {
- .open = gen_rtc_proc_open,
- .read = seq_read,
- .llseek = seq_lseek,
- .release = single_release,
-};
-
-static int __init gen_rtc_proc_init(void)
-{
- struct proc_dir_entry *r;
-
- r = proc_create("driver/rtc", 0, NULL, &gen_rtc_proc_fops);
- if (!r)
- return -ENOMEM;
- return 0;
-}
-#else
-static inline int gen_rtc_proc_init(void) { return 0; }
-#endif /* CONFIG_PROC_FS */
-
-
-/*
- * The various file operations we support.
- */
-
-static const struct file_operations gen_rtc_fops = {
- .owner = THIS_MODULE,
-#ifdef CONFIG_GEN_RTC_X
- .read = gen_rtc_read,
- .poll = gen_rtc_poll,
-#endif
- .unlocked_ioctl = gen_rtc_unlocked_ioctl,
- .open = gen_rtc_open,
- .release = gen_rtc_release,
- .llseek = noop_llseek,
-};
-
-static struct miscdevice rtc_gen_dev =
-{
- .minor = RTC_MINOR,
- .name = "rtc",
- .fops = &gen_rtc_fops,
-};
-
-static int __init rtc_generic_init(void)
-{
- int retval;
-
- printk(KERN_INFO "Generic RTC Driver v%s\n", RTC_VERSION);
-
- retval = misc_register(&rtc_gen_dev);
- if (retval < 0)
- return retval;
-
- retval = gen_rtc_proc_init();
- if (retval) {
- misc_deregister(&rtc_gen_dev);
- return retval;
- }
-
- return 0;
-}
-
-static void __exit rtc_generic_exit(void)
-{
- remove_proc_entry ("driver/rtc", NULL);
- misc_deregister(&rtc_gen_dev);
-}
-
-
-module_init(rtc_generic_init);
-module_exit(rtc_generic_exit);
-
-MODULE_AUTHOR("Richard Zidlicky");
-MODULE_LICENSE("GPL");
-MODULE_ALIAS_MISCDEV(RTC_MINOR);
projects / platform / kernel / linux-rpi.git / commitdiff