Daniel Carosone wrote:
> On Mon, Apr 10, 2006 at 01:12:54PM -0700, Bill Studenmund wrote:
>>3) Make some layer further up the chain do the checking. The idea is that 
>>devices that support FUA would somehow announce this, and code further up 

> As well as the additional infrastructure, 3 sounds like it would need
> ~as much rototillage as 2, since each driver would still have to know
> and announce its capability - regardless of whether via an error path

I recently used a similar strategy in midi(4), where it actually saved
quite a bit of tillage because only two out of the many drivers below
needed to be changed to announce they had the new capability ... the
win is, all the ones that don't, don't need to announce anything. (I
haven't committed the code yet, but it can be viewed from PR 32442.)

As long as the proportions are similar (a few devices supporting FUA
out of many that don't), the 'announce' pattern seems attractive. I sort
of improvised a hackish way to do it in midi, but maybe a general i/f for
such 'announcements' could become part of the autoconfigure stuff.

-Chap