Why power the module via its ground pin?
Not very safe practice.
AFAIK, the 2N2222 is a NPN device, so you'll have to conect its collector to the power rail, base via a 100r resistor to your output port, and the emitor to your module.
The output will be (power rail) 5v - 0.7 (transistor drop) = 4.3v



Cheers sda