Now that we are registering a clock even for the PPS master when it
supports that (i.e. when it is a PHC), introduce a new API to retrieve
its clock in order to add timestamps to it.
The PHC master can be synchronized to the extts events of a PHC slave,
when in automatic mode.
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Some PTP Hardware Clocks have input pins that can generate time stamps
on the edges of external signals. This functionality can be used in
various ways. For example, one can synchronize a PHC device to a
global time source by taking a Pulse Per Second signal from the source
into the PHC. This patch adds support for synchronizing one or more
PHC slaves to a given master clock.
The implementation follows a modular design that allows adding
different kinds of master clocks in the future. This patch starts off
with a single "generic" PPS master, meaning a PPS signal that lacks
and time or date information. The generic master assumes that the
Linux system time is approximately correct (by NTP or RTC for example)
in order to calculate the time of the incoming PPS edges.
Signed-off-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: Balint Ferencz <fernya@gmail.com>
Vladimir Oltean
Richard Cochran