The PPS time stamps are always made by the system clock, don't allow
running the PPS loop with other clocks.
Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com>
In the PPS loop, instead of setting the system clock from the PHC only
once on start, read PHC with each PPS sample and use the time stamp to
get the whole number of seconds in the offset. This will prevent phc2sys
from losing track of the system clock.
Also, check if the PPS is synchronized to the PHC.
Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com>