Like "joelster" said... The
FASLink II has 12vdc (with seemingly up to 1amp) that is used to power 1 or 2 FC controllers. I used a right-angle XLR to directly power my Blackstar LiveLogic. I did have to disassemble the Blackstar to know if it could accept 12vdc (instead of the 9vdc noted), after looking up the voltage regulator (device/chip) I learned it could be powered with up to 15vdc (18vdc peak). That meant no extra work for me. It all works flawlessly!
Years ago I would use/hijack midi pins 1 & 5 (which are unused for midi) to add in a 9vdc power supply to create a 9vdc bus of sorts. I would then just use midi thru or other midi ports tap off of. Fairly common practice way back when. I'll do about anything to avoid wall-warts and power strips.