Assign turbo to a button ?

I use an 8BitDo SN30 pro+ with RPCS3. I have found the compatibility and feel to be just flawless with all PS3 games thus far, including a very solid d pad in the correct position for 2D games.
It has a turbo button that even works on the analog triggers if you like.
Just an option in case you are willing to spend some cash. I recommend it cause it's laid out like a DS4.