kern/113950: per-vchan mixer support

[Alexander Botero-Lowry]

>Number:         113950
>Category:       kern
>Synopsis:       per-vchan mixer support
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          change-request
>Submitter-Id:   current-users
>Arrival-Date:   Fri Jun 22 16:00:10 GMT 2007
>Closed-Date:
>Last-Modified:
>Originator:     Alexander Botero-Lowry
>Release:        FreeBSD 6.0-STABLE i386
>Organization:
>Environment:
System: FreeBSD freefall.freebsd.org 6.0-STABLE FreeBSD 6.0-STABLE #0: Sat Dec 10 03:18:20 UTC 2005 kensmith at freefall.freebsd.org:/usr/obj/usr/src/sys/FREEFALL i386

>Description:
	DragonFly has support for per-vchan volume control so that you can
adjust volume on an application level. This is a feature you usually have to
install some lame sound-server to get, and it would be really cool to have it
on FreeBSD. The Dfly commit log and links to the diffs are at:
http://leaf.dragonflybsd.org/mailarchive/commits/2007-06/msg00121.html

I tried to apply this myself, and while it was fairly trivial to apply against
STABLE, I wasn't able to really make sense of where stuff would go on CURRENT.
If it looks ok, and it doesn't take much shoehorning it would be really cool!	
>How-To-Repeat:
	Try to play two songs at the same time and mute one of them.
>Fix:
	shoehorn the dfly patches.

>Release-Note:
>Audit-Trail:
>Unformatted: