K 10
svn:author
V 5
gonzo
K 8
svn:date
V 27
2013-02-28T19:43:14.200598Z
K 7
svn:log
V 427
Add hooks for plugging platform-provided transfer backend.

In order to use platorm backend hardware driver should
impement three methods:
- platform_start_transfer and platform_finish_transfer
    to start and finish transfer
- platform_will_handle - check whether transaction is
    suitable for backend. If not - driver will fall back
    to PIO mode.

Submitted by:	Daisuke Aoyama <aoyama at peach.ne.jp>
Approved by:	ian@

END