(In reply to Alex Deucher from comment #247)
> Not until it's tested and it proves to work reliably on all the problematic
> systems here.

Unfortunately I tried your patch on kernel 3.17.1 and it doesn't work, my
system still hangs resuming after hibernate. Everything is working well with
DPM disabled.

$ lspci | grep VGA
01:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI]
RV620/M82 [Mobility Radeon HD 3450/3470]

Please let me know if I can provide any other useful information.