Takashi Iwai wrote:
Mark Brown wrote:
For applications which need to synchronise with external timebases such as broadcast TV applications the kernel monotonic time is not optimal as it includes adjustments from NTP and so may still include discontinuities due to that. A raw monotonic time which does not include any adjustments is available in the kernel from getrawmonotonic() so provide userspace with a new timestamp type SNDRV_PCM_TSTAMP_TYPE_MONOTONIC_RAW which provides timestamps based on this as an option.
This looks good to me. Or, thinking of the original use case, should we just replace ktime_get_ts() with getrawmonotonic()? The MONOTONIC mode is really to be monotonic.
This would break any applications that relate these timestamps to their own timestamps from clock_gettime(CLOCK_MONOTONIC).
Regards, Clemens