"resume doesn't work if I use the open source nvidia driver. Work-around:
use the nvidia proprietary one"
Reinitialising nvidia hardware requires parsing and executing a set of scripts held in the GPU's BIOS. The nvidia driver has no code to do this - nor has nvidia (the company) released any specifications to allow this to be done. The open-source nouveau driver has a reverse-engineered reimplementation of this code which may work on your hardware, but no guarantees are made.