This introduces the '-a' option in ts2phc, an option inspired from
phc2sys that puts the clocks in "automatic" mode. In this mode, ts2phc
listens, as a PMC, to port state change events from ptp4l, and detects
which port state machine, if any, has transitioned to PS_SLAVE. That
port's clock will become the synchronization master for the hierarchy
described by ts2phc.
The use case is a multi-switch DSA setup with boundary_clock_jbod, where
there is only one grandmaster, connected to one switch's port. The other
switches, connected together through a PPS signal, must adapt themselves
to this new source of time, while the switch connected to the GM must
not be synchronized by ts2phc because it is already synchronized by
ptp4l.
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Vladimir Oltean
Richard Cochran