Comment # 11 on bug 1220909 from Ryan Stucki

More info:
Can't get the Xbox360 controller to work with ANY of the old kernels (but I did
test it on other systems, hardware seems fine.)

The Steam Controller DID start working briefly on the latest build after
rebooting. It is recognized/works as /dev/input/js0, but then suddenly
"disconnects" after playing a game for a few minutes.

I kept dmesg -w open while turning it on until time of disconnection:
[ 3117.751031] hid-steam 0003:28DE:1142.0014: Steam Controller 'XXXXXXXXXX'
connected
[ 3117.798059] input: Microsoft X-Box 360 pad 0 as
/devices/virtual/input/input43
[ 3125.019944] hid-steam 0003:28DE:1142.0014: Steam Controller 'XXXXXXXXXX'
disconnected

It isn't recognized again until a reboot, after which the above (recognition
and then sudden disconnect) can be replicated.