[U-Boot] Chrome OS keyboard not responding on snow

I'm trying to run the latest u-boot on the old samsung exynos5250 chromebook (snow_defconfig). I've managed to get the u-boot console up but it doesn't respond to keyboard input.

I managed to hack the startup procedure to call dm_dump_all() which shows the the keyboard-controller of cros_ec was attached I think.

Anyone remember much about this board or have any tips on how I could start debugging this?

Thanks, -Adam