Possibly unless there is a comment in the code as to why a particular chip may be blacklisted.
You may be able to add the definition to the code compile and load the new driver and it would just work assuming the chip is old enough and didn’t do things too differently from existing supported chips… I did this for I think it was Radeon HD 8330 and a couple of the PALM based GPUs in IBM netbooks.
Also in the future why not make your own thread instead of commenting on 8 year old posts?