I am interested in moving forward this conversation. I have found myself
in a situation where I need to use multiple external timestamp channels
with different clients. In my specific application, I use channel 0 with
ts2phc to synchronize a PPS clock reference, and I want to use channel 1
to timestamp external events. Since ts2phc is consuming from the fifo, 
if I add another consumer everything starts to go wrong.

I would like to share my idea on how to solve this. Like Richard
mentions, I just create a separate work queue per channel, and add a
sysfs interface to dynamically be able to move queues from the
shared/multiplexed queue to individual queues.

This is the first time I try to contribute something using this mailing
list, so please forgive me if I'm doing something wrong.

Let me know what you thing about my code (the patch should be on the
next message). Thanks.

Xabier.