linux/arch/powerpc/sysdev/timer.c

82 lines
1.7 KiB
C

/*
* Common code to keep time when machine suspends.
*
* Copyright 2007 Johannes Berg <johannes@sipsolutions.net>
*
* GPLv2
*/
#include <linux/time.h>
#include <linux/sysdev.h>
#include <asm/rtc.h>
static unsigned long suspend_rtc_time;
/*
* Reset the time after a sleep.
*/
static int timer_resume(struct sys_device *dev)
{
struct timeval tv;
struct timespec ts;
struct rtc_time cur_rtc_tm;
unsigned long cur_rtc_time, diff;
/* get current RTC time and convert to seconds */
get_rtc_time(&cur_rtc_tm);
cur_rtc_time = mktime(cur_rtc_tm.tm_year + 1900,
cur_rtc_tm.tm_mon + 1,
cur_rtc_tm.tm_mday,
cur_rtc_tm.tm_hour,
cur_rtc_tm.tm_min,
cur_rtc_tm.tm_sec);
diff = cur_rtc_time - suspend_rtc_time;
/* adjust time of day by seconds that elapsed while
* we were suspended */
do_gettimeofday(&tv);
ts.tv_sec = tv.tv_sec + diff;
ts.tv_nsec = tv.tv_usec * NSEC_PER_USEC;
do_settimeofday(&ts);
return 0;
}
static int timer_suspend(struct sys_device *dev, pm_message_t state)
{
struct rtc_time suspend_rtc_tm;
WARN_ON(!ppc_md.get_rtc_time);
get_rtc_time(&suspend_rtc_tm);
suspend_rtc_time = mktime(suspend_rtc_tm.tm_year + 1900,
suspend_rtc_tm.tm_mon + 1,
suspend_rtc_tm.tm_mday,
suspend_rtc_tm.tm_hour,
suspend_rtc_tm.tm_min,
suspend_rtc_tm.tm_sec);
return 0;
}
static struct sysdev_class timer_sysclass = {
.resume = timer_resume,
.suspend = timer_suspend,
set_kset_name("timer"),
};
static struct sys_device device_timer = {
.id = 0,
.cls = &timer_sysclass,
};
static int time_init_device(void)
{
int error = sysdev_class_register(&timer_sysclass);
if (!error)
error = sysdev_register(&device_timer);
return error;
}
device_initcall(time_init_device);