A simple code using the TMCStepper and AccelStepper library to test the sensor-less homing feature of the TMC2209 stepper driver. Both libraries can be found in Arduino IDE's library manager. It is set up to home two stepper motors, you can uncomment the functions motorAHome() or motorBHome() to just test a single motor.
A circuit schematic, made with Cirkit Designer, for this setup can be viewed here.