linuxptp Code

Add a timer implementing the sync receive timeout.

This patch adds a new timer for use in 802.1AS-2011 applications. When
running as a slave in gPTP mode, the program must monitor both announce
and sync messages from the master. If either one goes missing, then we
trigger a BMC election. The sync timeout is actually reset by a valid
sync/follow up pair of messages.

Signed-off-by: Richard Cochran <richardcochran@...>

Rename the timer for sending sync messages.

This patch renames the per-port timer in order to make room in the
namespace for a timer that detects a sync message input timeout.

Signed-off-by: Richard Cochran <richardcochran@...>

Remove a useless variable from the file descriptor array data type.

It was a cute idea to have the raw Ethernet layer use just one socket,
but it ended up not working on some specific PTP time stamping hardware.

Signed-off-by: Richard Cochran <richardcochran@...>

Implement the master sync timer and message.

Signed-off-by: Richard Cochran <richardcochran@...>

Implement the master announce timer and message.

Signed-off-by: Richard Cochran <richardcochran@...>

Implement the port master qualification timer.

Signed-off-by: Richard Cochran <richardcochran@...>

Add transport over UDP IPv4.

Signed-off-by: Richard Cochran <richardcochran@...>

Add code to open and close PHC devices.

Signed-off-by: Richard Cochran <richardcochran@...>

Add the license, a readme, and some header files.

This commit gets the project off to a good start. The header files provide
some basic data types and definitions.

The README file will most probably grow over time.

Signed-off-by: Richard Cochran <richardcochran@...>