Hi.
One of the optical ports for the Fabry Perot laser is an input port for injection mode locking. So you could use an electrical bias to power the FP Laser then an input from the circulator to drive it. Finally routing the output back through the circulator. You may refer to these links for further help.
https://www.google.co.in/urlsa=t&rct=j&q=&esrc=s&source=web&cd=2&cad=rja&uact=8&ved=0ahUKEwjmgtrAutnNAhWDkZQKHcuzAK4QFgguMAE&url=http%3A%2F%2Foptiwave.com%2F%3Fwpdmdl%3D104&usg=AFQjCNHsqmAw78UVgKXWQv4vUN0iB0nQEg&bvm=bv.126130881,d.dGo
Thanks