If this is your brake you can see the tab to lift the linkage off on the right side

https://www.tektro.com/products.php?p=53

If it's the TRP T820/920 then according to this document you need an inline barrel adjuster
https://www.trpbrakes.com/...etup%20-%20final.pdf

This document from TRP

http://trpbrakes.com/pubs/T920.pdf

See section C.2 it says you can disconnect the arm I mentioned earlier