LinuxCNC questions

You can, if you want, gate the probe signal based on the motion type, so that the probe is only active on probe moves.

If I was doing this I would probably use a mux_generic as that accepts an integer input, and motion.motion-type is an S32.
You would still need to conver the S32 motion type to U32 for the mux_generic.sel-int
The advantage of doing it this way is that you have control of which motion-types get the probe value, and can control the default input for the other motion types.

(so typicaly you would setp inputs 0,1,2,3 & 6 to 1 (or 0) and then net 4 and 5 to the actual probe / toolsetter.)

linuxcnc.org/docs/2.8/html/man/man9/motion.9.html
linuxcnc.org/docs/2.8/html/man/man9/mux_generic.9.html

Rather than try to guess what of this is not obvious, I will encourage you to ask.