The following three patches address various minor nits. They are all safe and I have been running with them for several months on a wide variety of AMD GPUs
The first patch: [PATCH 1/3] drm/radeon/kms: use crtc-specific dpms functions in does not change the functionality and affects the function that is used only by r100 ASICs, but make the code more correct (strictly speaking).
The second patch: [PATCH 2/3] drm/radeon/kms: fix the crtc number check makes the crtc number check consistent with the way it is done in the rest of the driver code without affecting the functionality. It was actually sent a few months ago and reviewed, but apparently forgotten (cf. http://lists.freedesktop.org/archives/dri-devel/2011-May/010935.html)
The third patch: [PATCH 3/3] drm/radeon/kms: use num_crtc instead of hard-coded value Prevents a possible trouble waiting to happen if AMD ever makes a GPU with more than 6 CRTCs. I don't know what's cooking in their kitchen but if such a GPU ever comes out, this will prevent at least one regression ;-)