Re: [Linuxptp-users] Question about hardware receive filter mode

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

On Thu, Dec 19, 2013 at 09:43:47PM +0000, Keller, Jacob E wrote:
 
> The other filters are available as historically the interface supported
> them, even if it wasn't really useful.

The various filters correspond to the available modes in early time
stamping hardware implementations.

As Jake said, only the "all event" filter is interesting. In ptp4l, we
try to use

    HWTSTAMP_FILTER_PTP_V2_EVENT,

but we fall back to

   HWTSTAMP_FILTER_PTP_V2_L4_EVENT, or
   HWTSTAMP_FILTER_PTP_V2_L2_EVENT

depending on the transport. We never use any other filter.

HTH,
Richard