I have a bare-bones Arduino (basically an Atmega328P) and a Raspberry Pi 2. I have them communicating with each other over I2C and a 5v/3.3v logic level converter.
Right now I power the Pi (micro-usb) and Atmega (5v from FTDI) separately. I have a 12V 6A DC PSU (5.5mm barrel jack) that I would like to use to power both the Pi and the Atmega (and my LED strip lighting).
What's a good way to go about doing this? I have a few LM7805 chips on hand if I could use those, but I'm open to ordering new stuff if I have to.
Do I convert to 5v from 12v and then use that to power both Pi via GPIO and Atmega or is there current draw issues with doing that?