[LinuxCNC/linuxcnc Issue#441] Touchy gives an error if trying to unhome Z on a lathe

Here are the steps I follow to reproduce the issue:

1. Using Touchy in a 2-axis trivkins lathe config
2. Home all (note that no asterix indicates that Z is homed, minor issue)
3. Select Z and press “unhome”

This is what I expected to happen:

Z to Unhome.

This is what happened instead:

Error message “Cannot unhome invalid joint 2 (max 1)”

It worked properly before this:

It’s a JA thing, I reckon.

Information about my hardware and software:

Latest master compiled RTAI.