Comment 9 for bug 82680

Vincenzo & DanaGoyette: you seem to be describing two separate and different issues here.

DanaGoyette: Your /proc/devices doesn't show " 254 mmc".

This is probably because you have not got "mmc_block" and/or "mmc_core" loaded.

Try "lsmod | grep mmc"

if it doesn't show both mmc_core and mmc_block try

modprobe mmc_core
modprobe mmc_block

This may fix your problem. It if does then this needs further investigation as to why udev/modprobe didn't load it automatically.

Vincenzo: your problem is different. It is likely your machine isn't loading the correct low level mmc driver. Please attach a full dmesg and the full output from lsmod. Thanks.