Commit 220a60a4 authored by Ben Hutchings's avatar Ben Hutchings
Browse files

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: default avatarBen Hutchings <bhutchings@solarflare.com>
parent ef2c7d7b
......@@ -300,6 +300,11 @@ void ptp_clock_event(struct ptp_clock *ptp, struct ptp_clock_event *event)
pps_get_ts(&evt);
pps_event(ptp->pps_source, &evt, PTP_PPS_EVENT, NULL);
break;
case PTP_CLOCK_PPSUSR:
pps_event(ptp->pps_source, &event->pps_times,
PTP_PPS_EVENT, NULL);
break;
}
}
EXPORT_SYMBOL(ptp_clock_event);
......
......@@ -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 */
......@@ -21,6 +21,7 @@
#ifndef _PTP_CLOCK_KERNEL_H_
#define _PTP_CLOCK_KERNEL_H_
#include <linux/pps_kernel.h>
#include <linux/ptp_clock.h>
......@@ -110,6 +111,7 @@ enum ptp_clock_events {
PTP_CLOCK_ALARM,
PTP_CLOCK_EXTTS,
PTP_CLOCK_PPS,
PTP_CLOCK_PPSUSR,
};
/**
......@@ -117,13 +119,17 @@ enum ptp_clock_events {
*
* @type: One of the ptp_clock_events enumeration values.
* @index: Identifies the source of the event.
* @timestamp: When the event occured.
* @timestamp: When the event occurred (%PTP_CLOCK_EXTTS only).
* @pps_times: When the event occurred (%PTP_CLOCK_PPSUSR only).
*/
struct ptp_clock_event {
int type;
int index;
u64 timestamp;
union {
u64 timestamp;
struct pps_event_time pps_times;
};
};
/**
......
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