diff options
Diffstat (limited to 'drivers/char/ds1286.c')
-rw-r--r-- | drivers/char/ds1286.c | 585 |
1 files changed, 0 insertions, 585 deletions
diff --git a/drivers/char/ds1286.c b/drivers/char/ds1286.c deleted file mode 100644 index 5329d482b582..000000000000 --- a/drivers/char/ds1286.c +++ /dev/null @@ -1,585 +0,0 @@ -/* - * DS1286 Real Time Clock interface for Linux - * - * Copyright (C) 1998, 1999, 2000 Ralf Baechle - * - * Based on code written by 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/rtc pseudo-file for status - * information. - * - * The ioctls can be used to set the interrupt behaviour and generation rate - * from the RTC via IRQ 8. Then the /dev/rtc interface can be used to make - * use of these timer interrupts, be they interval 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. - */ -#include <linux/ds1286.h> -#include <linux/smp_lock.h> -#include <linux/types.h> -#include <linux/errno.h> -#include <linux/miscdevice.h> -#include <linux/slab.h> -#include <linux/ioport.h> -#include <linux/fcntl.h> -#include <linux/init.h> -#include <linux/poll.h> -#include <linux/rtc.h> -#include <linux/spinlock.h> -#include <linux/bcd.h> -#include <linux/proc_fs.h> -#include <linux/jiffies.h> - -#include <asm/uaccess.h> -#include <asm/system.h> - -#define DS1286_VERSION "1.0" - -/* - * 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 DECLARE_WAIT_QUEUE_HEAD(ds1286_wait); - -static ssize_t ds1286_read(struct file *file, char *buf, - size_t count, loff_t *ppos); - -static int ds1286_ioctl(struct inode *inode, struct file *file, - unsigned int cmd, unsigned long arg); - -static unsigned int ds1286_poll(struct file *file, poll_table *wait); - -static void ds1286_get_alm_time (struct rtc_time *alm_tm); -static void ds1286_get_time(struct rtc_time *rtc_tm); -static int ds1286_set_time(struct rtc_time *rtc_tm); - -static inline unsigned char ds1286_is_updating(void); - -static DEFINE_SPINLOCK(ds1286_lock); - -static int ds1286_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 */ -#define RTC_TIMER_ON 0x02 /* missed irq timer active */ - -static unsigned char ds1286_status; /* bitmapped status byte. */ - -static unsigned char days_in_mo[] = { - 0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 -}; - -/* - * Now all the various file operations that we export. - */ - -static ssize_t ds1286_read(struct file *file, char *buf, - size_t count, loff_t *ppos) -{ - return -EIO; -} - -static int ds1286_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 */ - { - unsigned long flags; - unsigned char val; - - if (!capable(CAP_SYS_TIME)) - return -EACCES; - - spin_lock_irqsave(&ds1286_lock, flags); - val = rtc_read(RTC_CMD); - val |= RTC_TDM; - rtc_write(val, RTC_CMD); - spin_unlock_irqrestore(&ds1286_lock, flags); - - return 0; - } - case RTC_AIE_ON: /* Allow alarm interrupts. */ - { - unsigned long flags; - unsigned char val; - - if (!capable(CAP_SYS_TIME)) - return -EACCES; - - spin_lock_irqsave(&ds1286_lock, flags); - val = rtc_read(RTC_CMD); - val &= ~RTC_TDM; - rtc_write(val, RTC_CMD); - spin_unlock_irqrestore(&ds1286_lock, flags); - - return 0; - } - case RTC_WIE_OFF: /* Mask watchdog int. enab. bit */ - { - unsigned long flags; - unsigned char val; - - if (!capable(CAP_SYS_TIME)) - return -EACCES; - - spin_lock_irqsave(&ds1286_lock, flags); - val = rtc_read(RTC_CMD); - val |= RTC_WAM; - rtc_write(val, RTC_CMD); - spin_unlock_irqrestore(&ds1286_lock, flags); - - return 0; - } - case RTC_WIE_ON: /* Allow watchdog interrupts. */ - { - unsigned long flags; - unsigned char val; - - if (!capable(CAP_SYS_TIME)) - return -EACCES; - - spin_lock_irqsave(&ds1286_lock, flags); - val = rtc_read(RTC_CMD); - val &= ~RTC_WAM; - rtc_write(val, RTC_CMD); - spin_unlock_irqrestore(&ds1286_lock, flags); - - 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(wtime)); - ds1286_get_alm_time(&wtime); - break; - } - case RTC_ALM_SET: /* Store a time into the alarm */ - { - /* - * This expects a struct rtc_time. Writing 0xff means - * "don't care" or "match all". Only the tm_hour, - * tm_min and tm_sec are used. - */ - unsigned char hrs, min, sec; - struct rtc_time alm_tm; - - if (!capable(CAP_SYS_TIME)) - return -EACCES; - - if (copy_from_user(&alm_tm, (struct rtc_time*)arg, - sizeof(struct rtc_time))) - return -EFAULT; - - hrs = alm_tm.tm_hour; - min = alm_tm.tm_min; - sec = alm_tm.tm_sec; - - if (hrs >= 24) - hrs = 0xff; - - if (min >= 60) - min = 0xff; - - if (sec != 0) - return -EINVAL; - - min = BIN2BCD(min); - min = BIN2BCD(hrs); - - spin_lock(&ds1286_lock); - rtc_write(hrs, RTC_HOURS_ALARM); - rtc_write(min, RTC_MINUTES_ALARM); - spin_unlock(&ds1286_lock); - - return 0; - } - case RTC_RD_TIME: /* Read the time/date from RTC */ - { - memset(&wtime, 0, sizeof(wtime)); - ds1286_get_time(&wtime); - break; - } - case RTC_SET_TIME: /* Set the RTC */ - { - struct rtc_time rtc_tm; - - if (!capable(CAP_SYS_TIME)) - return -EACCES; - - if (copy_from_user(&rtc_tm, (struct rtc_time*)arg, - sizeof(struct rtc_time))) - return -EFAULT; - - return ds1286_set_time(&rtc_tm); - } - default: - return -EINVAL; - } - 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. - */ - -static int ds1286_open(struct inode *inode, struct file *file) -{ - lock_kernel(); - spin_lock_irq(&ds1286_lock); - - if (ds1286_status & RTC_IS_OPEN) - goto out_busy; - - ds1286_status |= RTC_IS_OPEN; - - spin_unlock_irq(&ds1286_lock); - unlock_kernel(); - return 0; - -out_busy: - spin_lock_irq(&ds1286_lock); - unlock_kernel(); - return -EBUSY; -} - -static int ds1286_release(struct inode *inode, struct file *file) -{ - ds1286_status &= ~RTC_IS_OPEN; - - return 0; -} - -static unsigned int ds1286_poll(struct file *file, poll_table *wait) -{ - poll_wait(file, &ds1286_wait, wait); - - return 0; -} - -/* - * The various file operations we support. - */ - -static const struct file_operations ds1286_fops = { - .llseek = no_llseek, - .read = ds1286_read, - .poll = ds1286_poll, - .ioctl = ds1286_ioctl, - .open = ds1286_open, - .release = ds1286_release, -}; - -static struct miscdevice ds1286_dev= -{ - .minor = RTC_MINOR, - .name = "rtc", - .fops = &ds1286_fops, -}; - -static int __init ds1286_init(void) -{ - int err; - - printk(KERN_INFO "DS1286 Real Time Clock Driver v%s\n", DS1286_VERSION); - - err = misc_register(&ds1286_dev); - if (err) - goto out; - - if (!create_proc_read_entry("driver/rtc", 0, 0, ds1286_read_proc, NULL)) { - err = -ENOMEM; - - goto out_deregister; - } - - return 0; - -out_deregister: - misc_deregister(&ds1286_dev); - -out: - return err; -} - -static void __exit ds1286_exit(void) -{ - remove_proc_entry("driver/rtc", NULL); - misc_deregister(&ds1286_dev); -} - -static char *days[] = { - "***", "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat" -}; - -/* - * Info exported via "/proc/rtc". - */ -static int ds1286_proc_output(char *buf) -{ - char *p, *s; - struct rtc_time tm; - unsigned char hundredth, month, cmd, amode; - - p = buf; - - ds1286_get_time(&tm); - hundredth = rtc_read(RTC_HUNDREDTH_SECOND); - BCD_TO_BIN(hundredth); - - p += sprintf(p, - "rtc_time\t: %02d:%02d:%02d.%02d\n" - "rtc_date\t: %04d-%02d-%02d\n", - tm.tm_hour, tm.tm_min, tm.tm_sec, hundredth, - tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday); - - /* - * 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. - */ - ds1286_get_alm_time(&tm); - p += sprintf(p, "alarm\t\t: %s ", days[tm.tm_wday]); - if (tm.tm_hour <= 24) - p += sprintf(p, "%02d:", tm.tm_hour); - else - p += sprintf(p, "**:"); - - if (tm.tm_min <= 59) - p += sprintf(p, "%02d\n", tm.tm_min); - else - p += sprintf(p, "**\n"); - - month = rtc_read(RTC_MONTH); - p += sprintf(p, - "oscillator\t: %s\n" - "square_wave\t: %s\n", - (month & RTC_EOSC) ? "disabled" : "enabled", - (month & RTC_ESQW) ? "disabled" : "enabled"); - - amode = ((rtc_read(RTC_MINUTES_ALARM) & 0x80) >> 5) | - ((rtc_read(RTC_HOURS_ALARM) & 0x80) >> 6) | - ((rtc_read(RTC_DAY_ALARM) & 0x80) >> 7); - if (amode == 7) s = "each minute"; - else if (amode == 3) s = "minutes match"; - else if (amode == 1) s = "hours and minutes match"; - else if (amode == 0) s = "days, hours and minutes match"; - else s = "invalid"; - p += sprintf(p, "alarm_mode\t: %s\n", s); - - cmd = rtc_read(RTC_CMD); - p += sprintf(p, - "alarm_enable\t: %s\n" - "wdog_alarm\t: %s\n" - "alarm_mask\t: %s\n" - "wdog_alarm_mask\t: %s\n" - "interrupt_mode\t: %s\n" - "INTB_mode\t: %s_active\n" - "interrupt_pins\t: %s\n", - (cmd & RTC_TDF) ? "yes" : "no", - (cmd & RTC_WAF) ? "yes" : "no", - (cmd & RTC_TDM) ? "disabled" : "enabled", - (cmd & RTC_WAM) ? "disabled" : "enabled", - (cmd & RTC_PU_LVL) ? "pulse" : "level", - (cmd & RTC_IBH_LO) ? "low" : "high", - (cmd & RTC_IPSW) ? "unswapped" : "swapped"); - - return p - buf; -} - -static int ds1286_read_proc(char *page, char **start, off_t off, - int count, int *eof, void *data) -{ - int len = ds1286_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 - */ -static inline unsigned char ds1286_is_updating(void) -{ - return rtc_read(RTC_CMD) & RTC_TE; -} - - -static void ds1286_get_time(struct rtc_time *rtc_tm) -{ - unsigned char save_control; - unsigned long flags; - - /* - * 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 RTC_UIP. - * 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 (ds1286_is_updating() != 0) - msleep(20); - - /* - * 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_irqsave(&ds1286_lock, flags); - save_control = rtc_read(RTC_CMD); - rtc_write((save_control|RTC_TE), RTC_CMD); - - rtc_tm->tm_sec = rtc_read(RTC_SECONDS); - rtc_tm->tm_min = rtc_read(RTC_MINUTES); - rtc_tm->tm_hour = rtc_read(RTC_HOURS) & 0x3f; - rtc_tm->tm_mday = rtc_read(RTC_DATE); - rtc_tm->tm_mon = rtc_read(RTC_MONTH) & 0x1f; - rtc_tm->tm_year = rtc_read(RTC_YEAR); - - rtc_write(save_control, RTC_CMD); - spin_unlock_irqrestore(&ds1286_lock, flags); - - 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 < 45) - rtc_tm->tm_year += 30; - if ((rtc_tm->tm_year += 40) < 70) - rtc_tm->tm_year += 100; - - rtc_tm->tm_mon--; -} - -static int ds1286_set_time(struct rtc_time *rtc_tm) -{ - unsigned char mon, day, hrs, min, sec, leap_yr; - unsigned char save_control; - unsigned int yrs; - unsigned long flags; - - - 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 -= 1940) > 255) /* They are unsigned */ - 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_irqsave(&ds1286_lock, flags); - save_control = rtc_read(RTC_CMD); - rtc_write((save_control|RTC_TE), RTC_CMD); - - rtc_write(yrs, RTC_YEAR); - rtc_write(mon, RTC_MONTH); - rtc_write(day, RTC_DATE); - rtc_write(hrs, RTC_HOURS); - rtc_write(min, RTC_MINUTES); - rtc_write(sec, RTC_SECONDS); - rtc_write(0, RTC_HUNDREDTH_SECOND); - - rtc_write(save_control, RTC_CMD); - spin_unlock_irqrestore(&ds1286_lock, flags); - - return 0; -} - -static void ds1286_get_alm_time(struct rtc_time *alm_tm) -{ - unsigned char cmd; - unsigned long flags; - - /* - * Only the values that we read from the RTC are set. That - * means only tm_wday, tm_hour, tm_min. - */ - spin_lock_irqsave(&ds1286_lock, flags); - alm_tm->tm_min = rtc_read(RTC_MINUTES_ALARM) & 0x7f; - alm_tm->tm_hour = rtc_read(RTC_HOURS_ALARM) & 0x1f; - alm_tm->tm_wday = rtc_read(RTC_DAY_ALARM) & 0x07; - cmd = rtc_read(RTC_CMD); - spin_unlock_irqrestore(&ds1286_lock, flags); - - BCD_TO_BIN(alm_tm->tm_min); - BCD_TO_BIN(alm_tm->tm_hour); - alm_tm->tm_sec = 0; -} - -module_init(ds1286_init); -module_exit(ds1286_exit); - -MODULE_AUTHOR("Ralf Baechle"); -MODULE_LICENSE("GPL"); -MODULE_ALIAS_MISCDEV(RTC_MINOR); |