- Use configfs for config stuff.  This will require changes to the
  user space code.

- dgrp_send() and dgrp_receive() could use some refactoring

- Don't automatically create CHAN_MAX (64) channel array entries for
  every device as many devices are going to have much less than 64
  channels.

- The locking needs to be checked.  It seems haphazardly done in most
  places.

- Check Kconfig dependencies