linux/drivers/sbus/char/rtc.c

276 lines
7.0 KiB
C

/* $Id: rtc.c,v 1.28 2001/10/08 22:19:51 davem Exp $
*
* Linux/SPARC Real Time Clock Driver
* Copyright (C) 1996 Thomas K. Dyas (tdyas@eden.rutgers.edu)
*
* This is a little driver that lets a user-level program access
* the SPARC Mostek real time clock chip. It is no use unless you
* use the modified clock utility.
*
* Get the modified clock utility from:
* ftp://vger.kernel.org/pub/linux/Sparc/userland/clock.c
*/
#include <linux/module.h>
#include <linux/smp_lock.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/miscdevice.h>
#include <linux/slab.h>
#include <linux/fcntl.h>
#include <linux/poll.h>
#include <linux/init.h>
#include <asm/io.h>
#include <asm/mostek.h>
#include <asm/system.h>
#include <asm/uaccess.h>
#include <asm/rtc.h>
static int rtc_busy = 0;
/* This is the structure layout used by drivers/char/rtc.c, we
* support that driver's ioctls so that things are less messy in
* userspace.
*/
struct rtc_time_generic {
int tm_sec;
int tm_min;
int tm_hour;
int tm_mday;
int tm_mon;
int tm_year;
int tm_wday;
int tm_yday;
int tm_isdst;
};
#define RTC_AIE_ON _IO('p', 0x01) /* Alarm int. enable on */
#define RTC_AIE_OFF _IO('p', 0x02) /* ... off */
#define RTC_UIE_ON _IO('p', 0x03) /* Update int. enable on */
#define RTC_UIE_OFF _IO('p', 0x04) /* ... off */
#define RTC_PIE_ON _IO('p', 0x05) /* Periodic int. enable on */
#define RTC_PIE_OFF _IO('p', 0x06) /* ... off */
#define RTC_WIE_ON _IO('p', 0x0f) /* Watchdog int. enable on */
#define RTC_WIE_OFF _IO('p', 0x10) /* ... off */
#define RTC_RD_TIME _IOR('p', 0x09, struct rtc_time_generic) /* Read RTC time */
#define RTC_SET_TIME _IOW('p', 0x0a, struct rtc_time_generic) /* Set RTC time */
#define RTC_ALM_SET _IOW('p', 0x07, struct rtc_time) /* Set alarm time */
#define RTC_ALM_READ _IOR('p', 0x08, struct rtc_time) /* Read alarm time */
#define RTC_IRQP_READ _IOR('p', 0x0b, unsigned long) /* Read IRQ rate */
#define RTC_IRQP_SET _IOW('p', 0x0c, unsigned long) /* Set IRQ rate */
#define RTC_EPOCH_READ _IOR('p', 0x0d, unsigned long) /* Read epoch */
#define RTC_EPOCH_SET _IOW('p', 0x0e, unsigned long) /* Set epoch */
#define RTC_WKALM_SET _IOW('p', 0x0f, struct rtc_wkalrm)/* Set wakeup alarm*/
#define RTC_WKALM_RD _IOR('p', 0x10, struct rtc_wkalrm)/* Get wakeup alarm*/
#define RTC_PLL_GET _IOR('p', 0x11, struct rtc_pll_info) /* Get PLL correction */
#define RTC_PLL_SET _IOW('p', 0x12, struct rtc_pll_info) /* Set PLL correction */
/* Retrieve the current date and time from the real time clock. */
static void get_rtc_time(struct rtc_time *t)
{
void __iomem *regs = mstk48t02_regs;
u8 tmp;
spin_lock_irq(&mostek_lock);
tmp = mostek_read(regs + MOSTEK_CREG);
tmp |= MSTK_CREG_READ;
mostek_write(regs + MOSTEK_CREG, tmp);
t->sec = MSTK_REG_SEC(regs);
t->min = MSTK_REG_MIN(regs);
t->hour = MSTK_REG_HOUR(regs);
t->dow = MSTK_REG_DOW(regs);
t->dom = MSTK_REG_DOM(regs);
t->month = MSTK_REG_MONTH(regs);
t->year = MSTK_CVT_YEAR( MSTK_REG_YEAR(regs) );
tmp = mostek_read(regs + MOSTEK_CREG);
tmp &= ~MSTK_CREG_READ;
mostek_write(regs + MOSTEK_CREG, tmp);
spin_unlock_irq(&mostek_lock);
}
/* Set the current date and time inthe real time clock. */
void set_rtc_time(struct rtc_time *t)
{
void __iomem *regs = mstk48t02_regs;
u8 tmp;
spin_lock_irq(&mostek_lock);
tmp = mostek_read(regs + MOSTEK_CREG);
tmp |= MSTK_CREG_WRITE;
mostek_write(regs + MOSTEK_CREG, tmp);
MSTK_SET_REG_SEC(regs,t->sec);
MSTK_SET_REG_MIN(regs,t->min);
MSTK_SET_REG_HOUR(regs,t->hour);
MSTK_SET_REG_DOW(regs,t->dow);
MSTK_SET_REG_DOM(regs,t->dom);
MSTK_SET_REG_MONTH(regs,t->month);
MSTK_SET_REG_YEAR(regs,t->year - MSTK_YEAR_ZERO);
tmp = mostek_read(regs + MOSTEK_CREG);
tmp &= ~MSTK_CREG_WRITE;
mostek_write(regs + MOSTEK_CREG, tmp);
spin_unlock_irq(&mostek_lock);
}
static int put_rtc_time_generic(void __user *argp, struct rtc_time *tm)
{
struct rtc_time_generic __user *utm = argp;
if (__put_user(tm->sec, &utm->tm_sec) ||
__put_user(tm->min, &utm->tm_min) ||
__put_user(tm->hour, &utm->tm_hour) ||
__put_user(tm->dom, &utm->tm_mday) ||
__put_user(tm->month, &utm->tm_mon) ||
__put_user(tm->year, &utm->tm_year) ||
__put_user(tm->dow, &utm->tm_wday) ||
__put_user(0, &utm->tm_yday) ||
__put_user(0, &utm->tm_isdst))
return -EFAULT;
return 0;
}
static int get_rtc_time_generic(struct rtc_time *tm, void __user *argp)
{
struct rtc_time_generic __user *utm = argp;
if (__get_user(tm->sec, &utm->tm_sec) ||
__get_user(tm->min, &utm->tm_min) ||
__get_user(tm->hour, &utm->tm_hour) ||
__get_user(tm->dom, &utm->tm_mday) ||
__get_user(tm->month, &utm->tm_mon) ||
__get_user(tm->year, &utm->tm_year) ||
__get_user(tm->dow, &utm->tm_wday))
return -EFAULT;
return 0;
}
static int rtc_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
unsigned long arg)
{
struct rtc_time rtc_tm;
void __user *argp = (void __user *)arg;
switch (cmd) {
/* No interrupt support, return an error
* compatible with drivers/char/rtc.c
*/
case RTC_AIE_OFF:
case RTC_AIE_ON:
case RTC_PIE_OFF:
case RTC_PIE_ON:
case RTC_UIE_OFF:
case RTC_UIE_ON:
case RTC_IRQP_READ:
case RTC_IRQP_SET:
case RTC_EPOCH_SET:
case RTC_EPOCH_READ:
return -EINVAL;
case RTCGET:
case RTC_RD_TIME:
memset(&rtc_tm, 0, sizeof(struct rtc_time));
get_rtc_time(&rtc_tm);
if (cmd == RTCGET) {
if (copy_to_user(argp, &rtc_tm,
sizeof(struct rtc_time)))
return -EFAULT;
} else if (put_rtc_time_generic(argp, &rtc_tm))
return -EFAULT;
return 0;
case RTCSET:
case RTC_SET_TIME:
if (!capable(CAP_SYS_TIME))
return -EPERM;
if (cmd == RTCSET) {
if (copy_from_user(&rtc_tm, argp,
sizeof(struct rtc_time)))
return -EFAULT;
} else if (get_rtc_time_generic(&rtc_tm, argp))
return -EFAULT;
set_rtc_time(&rtc_tm);
return 0;
default:
return -EINVAL;
}
}
static int rtc_open(struct inode *inode, struct file *file)
{
int ret;
lock_kernel();
spin_lock_irq(&mostek_lock);
if (rtc_busy) {
ret = -EBUSY;
} else {
rtc_busy = 1;
ret = 0;
}
spin_unlock_irq(&mostek_lock);
unlock_kernel();
return ret;
}
static int rtc_release(struct inode *inode, struct file *file)
{
rtc_busy = 0;
return 0;
}
static const struct file_operations rtc_fops = {
.owner = THIS_MODULE,
.llseek = no_llseek,
.ioctl = rtc_ioctl,
.open = rtc_open,
.release = rtc_release,
};
static struct miscdevice rtc_dev = { RTC_MINOR, "rtc", &rtc_fops };
static int __init rtc_sun_init(void)
{
int error;
/* It is possible we are being driven by some other RTC chip
* and thus another RTC driver is handling things.
*/
if (!mstk48t02_regs)
return -ENODEV;
error = misc_register(&rtc_dev);
if (error) {
printk(KERN_ERR "rtc: unable to get misc minor for Mostek\n");
return error;
}
printk("rtc_sun_init: Registered Mostek RTC driver.\n");
return 0;
}
static void __exit rtc_sun_cleanup(void)
{
misc_deregister(&rtc_dev);
}
module_init(rtc_sun_init);
module_exit(rtc_sun_cleanup);
MODULE_LICENSE("GPL");