diff options
| -rw-r--r-- | drivers/rtc/class.c | 23 | ||||
| -rw-r--r-- | include/linux/time.h | 1 | ||||
| -rw-r--r-- | kernel/time/timekeeping.c | 56 |
3 files changed, 63 insertions, 17 deletions
diff --git a/drivers/rtc/class.c b/drivers/rtc/class.c index 39013867cbd6..4194e59e14cd 100644 --- a/drivers/rtc/class.c +++ b/drivers/rtc/class.c @@ -41,26 +41,21 @@ static void rtc_device_release(struct device *dev) * system's wall clock; restore it on resume(). */ -static struct timespec delta; static time_t oldtime; +static struct timespec oldts; static int rtc_suspend(struct device *dev, pm_message_t mesg) { struct rtc_device *rtc = to_rtc_device(dev); struct rtc_time tm; - struct timespec ts = current_kernel_time(); if (strcmp(dev_name(&rtc->dev), CONFIG_RTC_HCTOSYS_DEVICE) != 0) return 0; rtc_read_time(rtc, &tm); + ktime_get_ts(&oldts); rtc_tm_to_time(&tm, &oldtime); - /* RTC precision is 1 second; adjust delta for avg 1/2 sec err */ - set_normalized_timespec(&delta, - ts.tv_sec - oldtime, - ts.tv_nsec - (NSEC_PER_SEC >> 1)); - return 0; } @@ -70,10 +65,12 @@ static int rtc_resume(struct device *dev) struct rtc_time tm; time_t newtime; struct timespec time; + struct timespec newts; if (strcmp(dev_name(&rtc->dev), CONFIG_RTC_HCTOSYS_DEVICE) != 0) return 0; + ktime_get_ts(&newts); rtc_read_time(rtc, &tm); if (rtc_valid_tm(&tm) != 0) { pr_debug("%s: bogus resume time\n", dev_name(&rtc->dev)); @@ -85,15 +82,13 @@ static int rtc_resume(struct device *dev) pr_debug("%s: time travel!\n", dev_name(&rtc->dev)); return 0; } + /* calculate the RTC time delta */ + set_normalized_timespec(&time, newtime - oldtime, 0); - /* restore wall clock using delta against this RTC; - * adjust again for avg 1/2 second RTC sampling error - */ - set_normalized_timespec(&time, - newtime + delta.tv_sec, - (NSEC_PER_SEC >> 1) + delta.tv_nsec); - do_settimeofday(&time); + /* subtract kernel time between rtc_suspend to rtc_resume */ + time = timespec_sub(time, timespec_sub(newts, oldts)); + timekeeping_inject_sleeptime(&time); return 0; } diff --git a/include/linux/time.h b/include/linux/time.h index 454a26205787..4ea5a75fcacd 100644 --- a/include/linux/time.h +++ b/include/linux/time.h @@ -126,6 +126,7 @@ struct timespec __current_kernel_time(void); /* does not take xtime_lock */ struct timespec get_monotonic_coarse(void); void get_xtime_and_monotonic_and_sleep_offset(struct timespec *xtim, struct timespec *wtom, struct timespec *sleep); +void timekeeping_inject_sleeptime(struct timespec *delta); #define CURRENT_TIME (current_kernel_time()) #define CURRENT_TIME_SEC ((struct timespec) { get_seconds(), 0 }) diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 8ad5d576755e..8e6a05a5915a 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -596,6 +596,58 @@ void __init timekeeping_init(void) static struct timespec timekeeping_suspend_time; /** + * __timekeeping_inject_sleeptime - Internal function to add sleep interval + * @delta: pointer to a timespec delta value + * + * Takes a timespec offset measuring a suspend interval and properly + * adds the sleep offset to the timekeeping variables. + */ +static void __timekeeping_inject_sleeptime(struct timespec *delta) +{ + xtime = timespec_add(xtime, *delta); + wall_to_monotonic = timespec_sub(wall_to_monotonic, *delta); + total_sleep_time = timespec_add(total_sleep_time, *delta); +} + + +/** + * timekeeping_inject_sleeptime - Adds suspend interval to timeekeeping values + * @delta: pointer to a timespec delta value + * + * This hook is for architectures that cannot support read_persistent_clock + * because their RTC/persistent clock is only accessible when irqs are enabled. + * + * This function should only be called by rtc_resume(), and allows + * a suspend offset to be injected into the timekeeping values. + */ +void timekeeping_inject_sleeptime(struct timespec *delta) +{ + unsigned long flags; + struct timespec ts; + + /* Make sure we don't set the clock twice */ + read_persistent_clock(&ts); + if (!(ts.tv_sec == 0 && ts.tv_nsec == 0)) + return; + + write_seqlock_irqsave(&xtime_lock, flags); + timekeeping_forward_now(); + + __timekeeping_inject_sleeptime(delta); + + timekeeper.ntp_error = 0; + ntp_clear(); + update_vsyscall(&xtime, &wall_to_monotonic, timekeeper.clock, + timekeeper.mult); + + write_sequnlock_irqrestore(&xtime_lock, flags); + + /* signal hrtimers about time change */ + clock_was_set(); +} + + +/** * timekeeping_resume - Resumes the generic timekeeping subsystem. * * This is for the generic clocksource timekeeping. @@ -615,9 +667,7 @@ static void timekeeping_resume(void) if (timespec_compare(&ts, &timekeeping_suspend_time) > 0) { ts = timespec_sub(ts, timekeeping_suspend_time); - xtime = timespec_add(xtime, ts); - wall_to_monotonic = timespec_sub(wall_to_monotonic, ts); - total_sleep_time = timespec_add(total_sleep_time, ts); + __timekeeping_inject_sleeptime(&ts); } /* re-base the last cycle value */ timekeeper.clock->cycle_last = timekeeper.clock->read(timekeeper.clock); |