https://bugs.freedesktop.org/show_bug.cgi?id=66963
--- Comment #64 from Scias shining.scias@gmail.com --- (In reply to comment #63)
Created attachment 83484 [details] successfully booting and waking up from suspend to ram dmesg with dpm=1, RV620/M82 [Mobility Radeon HD 3450/3470
Latest commit works fine here.
Yes suspend works fine if the power profile/state isn't set to battery. Try setting the battery state before.