Yes. It's just resistors producing different voltages. A joystick uses a potentiometer that's connected to ground and 5V so it can produce the full voltage range inbetween that. The ADC then converts that voltage to a value representing the position of the pot. When you calibrate it, it will assume the center is the voltage when it's calibrating, which should be 2.5V but in this case it would be 5.0V. Normally 2.5 = 0, 0.0 = 127 and 5.0 = -128, but with this it should be 5.0 = 0, 1.7 = 100, 0.0 = 128 or somewhere around that.