DRM might be not exact term here, basically "original" cameras had a chip that identified itself to the rPi driver and driver required that to work. That was b

DRM might be not exact term here, basically "original" cameras had a chip that identified itself to the rPi driver and driver required that to work. That was because the previous camera was widely copied and they wanted to not put money into making driver for a camera just for user to go and buy cheap copy