What kind of error do you get?
You also need to port your C code from TH/THC to ATen.
I’d recommend to get it working using the just in time extension compilation first and then proceed to the setup.py. In the tutorial linked above, the mechanism to compile the module there is:
from torch.utils.cpp_extension import load

lltm = load(name='lltm', sources=['lltm_cuda.cpp', 'lltm_cuda_kernel.cu'])

Once that works, moving to setup.py should be straightforward.
Best regards
Thomas