diff options
Diffstat (limited to 'apps/drivers/drv_hrt.h')
| -rw-r--r-- | apps/drivers/drv_hrt.h | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/apps/drivers/drv_hrt.h b/apps/drivers/drv_hrt.h index 3b493a81a..8a99eeca7 100644 --- a/apps/drivers/drv_hrt.h +++ b/apps/drivers/drv_hrt.h @@ -92,6 +92,22 @@ __EXPORT extern hrt_abstime ts_to_abstime(struct timespec *ts); __EXPORT extern void abstime_to_ts(struct timespec *ts, hrt_abstime abstime); /* + * Compute the delta between a timestamp taken in the past + * and now. + * + * This function is safe to use even if the timestamp is updated + * by an interrupt during execution. + */ +__EXPORT extern hrt_abstime hrt_elapsed_time(const volatile hrt_abstime *then); + +/* + * Store the absolute time in an interrupt-safe fashion. + * + * This function ensures that the timestamp cannot be seen half-written by an interrupt handler. + */ +__EXPORT extern hrt_abstime hrt_store_absolute_time(volatile hrt_abstime *now); + +/* * Call callout(arg) after delay has elapsed. * * If callout is NULL, this can be used to implement a timeout by testing the call |