diff options
Diffstat (limited to 'arch/powerpc/sysdev/timer.c')
-rw-r--r-- | arch/powerpc/sysdev/timer.c | 71 |
1 files changed, 71 insertions, 0 deletions
diff --git a/arch/powerpc/sysdev/timer.c b/arch/powerpc/sysdev/timer.c new file mode 100644 index 0000000..4a01748 --- /dev/null +++ b/arch/powerpc/sysdev/timer.c @@ -0,0 +1,71 @@ +/* + * 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); + rtc_tm_to_time(&cur_rtc_tm, &cur_rtc_time); + + 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); + rtc_tm_to_time(&suspend_rtc_tm, &suspend_rtc_time); + + 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); |