???
do you mean that you can't do something like this...

1. pick an axis you want to rotate on
2. at keyframe 1 set a key at 0 degrees on the axis you are rotating
3. Now go to say keyframe 30, rotate your obeject on the axis you are rotating to 360 degrees, and set a key on that.
4. activate the camera view you want to view the animation on, press play and watch your object rotate.

... and that should do the trick, but if it only plays once, then that means your timeline isn't set to loop its playback head. You can change that in the Maya's prefrences options. Just navigate to Window -> settings/preferences -> prefrences. In the prefrences dialog, goto the timeline section and in there is where you can change the playback prefrences according to your needs