Comment 19 for bug 897549

For enabling mass storage a workaround for the time being is below:

#Associate SDcard with lun0
echo /dev/block/mmcblk1p1 > /sys/devices/platform/musb-ux500.0/musb-hdrc/gadget/lun0/file

#configuration with mass storage and adb
echo 0 > /sys/class/android_usb/android0/enable
echo adb,mass_storage > /sys/class/android_usb/android0/functions
echo 1 > /sys/class/android_usb/android0/enable

#plugin usb cable

With this the sdcard gets mounted automatically when snowball is connected to a ubuntu PC
There is currently an issue with writing to the sdcard from the PC. Further investigation needed