Re: [Linuxptp-users] Error accessing /dev/ptp0

[Richard C. <ric...@gm...>]

On Thu, Aug 07, 2014 at 01:51:18AM +0800, Ronex Dicapriyo wrote:
> And by `ptp subsystem`, Do you refer "<kernel_source>/drivers/ptp" ?

Yes, some important files for the ptp subsystem are in drivers/ptp,
but there are also drivers there.

Overall it is not as simple you try to make it. When we say "driver"
this can mean an Ethernet MAC driver, a PHY driver, or a PTP Hardware
Clock driver. Also, the core ptp code is mostly in drivers/ptp, but
there are some bits in the core networking code as well.

You have the source. Now go and read it!

> Does it sends ptp messages (like sync, delay etc..) to all the system in local LAN, and all the local IP's(Private and Public ethernet interface present on same host) ?

It sends multicast messages on the given interface.

> Now  How am I supposed to check output, I believe log messages along with wireshark might can help here.

You can use wireshark, sure. But the slave ptp4l program should print
out the current time offset, once per second.
 
> Does it stops after syncing the time between slave and master device ?

No.
 
> 3) Is it possible to establish ptp communication on one to one basis, means master sends ptp messages to slave IP,where ptp4l slave application is listening for master IP address ?

Unicast messaging is possible with the protocol, but it is not
implemented in linuxptp.

Thanks,
Richard