Earlier quoted context omitted.
XBox wired controller works well with mac as well thanks to the open source driver ( http://tattiebogle.net/index.php/ProjectRoot/Xbox360Controll... ). I have never faced any issue using the controller to play steam games on my mac.
I have kernel panic with this driver unfortunately. Wired XBox 360 with iMac 2011 and MacBook Pro 2012. Not sure what caused the issue... Because of it, I installed Windows via BootCamp and play all games over there, a bit inconvenient.
From my experience Android File Transfer causes kernal panic when used with the latest drivers.
Restart your machine, Terminate Android File Transfer and try plugging the controller again.