Okay, so I looked at the PS3 controller linux info. Seems everything's in mainline kernel now. So you only have to do the following:
0. Clear all your settings to remove any conflicts from previous sessions (optional, I would)
1. Make your bluetooth vissible permanently.
2. Plug controller in via USB.
3. Trust it when prompted (while it is plugged in). Prompt will be graphical if you have something like blueman installed, else it should prompt in the intetactive shell (if it does not, manually trust it)
4. Unplug it and wait a few secs.
5. Press the pairing button on the PS3 control and it should work fine.
0. Clear all your settings to remove any conflicts from previous sessions (optional, I would)
1. Make your bluetooth vissible permanently.
2. Plug controller in via USB.
3. Trust it when prompted (while it is plugged in). Prompt will be graphical if you have something like blueman installed, else it should prompt in the intetactive shell (if it does not, manually trust it)
4. Unplug it and wait a few secs.
5. Press the pairing button on the PS3 control and it should work fine.