diff options
author | Ben Hutchings <bhutchings@solarflare.com> | 2012-09-03 14:34:58 +0400 |
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committer | Ben Hutchings <bhutchings@solarflare.com> | 2012-09-08 00:13:28 +0400 |
commit | 220a60a425146b0e37998cc0b3082f0541aad866 (patch) | |
tree | 44e48c4489f8e354d17269d41db19d015d9b95fe /include/linux/pps_kernel.h | |
parent | ef2c7d7b59708d54213c7556a82d14de9a7e4475 (diff) | |
download | linux-220a60a425146b0e37998cc0b3082f0541aad866.tar.xz |
pps/ptp: Allow PHC devices to adjust PPS events for known delay
Initial version by Stuart Hodgson <smhodgson@solarflare.com>
Some PHC device drivers may deliver PPS events with a significant
and variable delay, but still be able to measure precisely what
that delay is.
Add a pps_sub_ts() function for subtracting a delay from the
timestamp(s) in a PPS event, and a PTP event type (PTP_CLOCK_PPSUSR)
for which the caller provides a complete PPS event.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Diffstat (limited to 'include/linux/pps_kernel.h')
-rw-r--r-- | include/linux/pps_kernel.h | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/include/linux/pps_kernel.h b/include/linux/pps_kernel.h index 94048547f29a..0cc45ae1afd5 100644 --- a/include/linux/pps_kernel.h +++ b/include/linux/pps_kernel.h @@ -116,5 +116,14 @@ static inline void pps_get_ts(struct pps_event_time *ts) #endif /* CONFIG_NTP_PPS */ +/* Subtract known time delay from PPS event time(s) */ +static inline void pps_sub_ts(struct pps_event_time *ts, struct timespec delta) +{ + ts->ts_real = timespec_sub(ts->ts_real, delta); +#ifdef CONFIG_NTP_PPS + ts->ts_raw = timespec_sub(ts->ts_raw, delta); +#endif +} + #endif /* LINUX_PPS_KERNEL_H */ |