tree aa924d5f10176fd45862edec97a350bbb74dc1d2
parent a80ef4e7c6143cba9671e1b8e3e52188f4077b9f
author James E. Blair <jeblair@redhat.com> 1484075973 -0800
committer James E. Blair <jeblair@redhat.com> 1484919810 -0800

Separate driver interfaces and make abstract

Separate the 4 driver interfaces into abstract interface classes,
and also add an abstract driver class.  Make the existing driver
implementations inherit from these as appropriate.

This should help clearly express which methods a given driver
needs to implement.

Change-Id: I918d35eced7b0581a65d53d2ebcd7124f3b3f0a6