freebsd-skq/share/man/man4/snd_uaudio.4
2010-01-15 16:01:22 +00:00

109 lines
3.5 KiB
Groff

.\" $NetBSD: uaudio.4,v 1.15 2002/02/12 19:53:57 jdolecek Exp $
.\"
.\" Copyright (c) 1999 The NetBSD Foundation, Inc.
.\" All rights reserved.
.\"
.\" This code is derived from software contributed to The NetBSD Foundation
.\" by Lennart Augustsson.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\" notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\" notice, this list of conditions and the following disclaimer in the
.\" documentation and/or other materials provided with the distribution.
.\" 3. All advertising materials mentioning features or use of this software
.\" must display the following acknowledgement:
.\" This product includes software developed by the NetBSD
.\" Foundation, Inc. and its contributors.
.\" 4. Neither the name of The NetBSD Foundation nor the names of its
.\" contributors may be used to endorse or promote products derived
.\" from this software without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
.\" POSSIBILITY OF SUCH DAMAGE.
.\"
.\" $FreeBSD$
.\"
.Dd December 15, 2005
.Dt SND_UAUDIO 4
.Os
.Sh NAME
.Nm snd_uaudio
.Nd USB audio device driver
.Sh SYNOPSIS
To compile this driver into the kernel, place the following lines in your
kernel configuration file:
.Bd -ragged -offset indent
.Cd "device sound"
.Cd "device usb"
.Cd "device snd_uaudio"
.Ed
.Pp
Alternatively, to load the driver as a module at boot time, place the
following line in
.Xr loader.conf 5 :
.Bd -literal -offset indent
snd_uaudio_load="YES"
.Ed
.Sh DESCRIPTION
The
.Nm
driver provides support for
.Tn USB
audio class devices.
.Pp
A
.Tn USB
audio device consists of a number of components:
input terminals (e.g.\& USB digital input), output terminals (e.g.\&
speakers), and a number of units in between (e.g.\& volume control).
.Pp
Refer to the
.Ql USB Audio Class Specification
for more information.
.Sh SEE ALSO
.Xr sound 4 ,
.Xr usb 4
.Rs
.%T "USB Audio Class Specifications"
.%U http://www.usb.org/developers/devclass_docs/
.Re
.Sh HISTORY
The
.Nm
driver first appeared in
.Fx 4.7 .
.Sh AUTHORS
This manual page was adopted from
.Nx 1.6
and modified for
.Fx
by
.An Hiten Pandya Aq hmp@FreeBSD.org .
.Sh BUGS
The
.Tn PCM
framework in
.Fx ,
as of this writing, does not handle device un-registrations in a properly
abstracted manner, i.e., a detach request is refused by the
.Tn PCM
framework if the device is in use.
For
.Tn USB
and supposedly other detach-able busses, it is necessary to allow the
device un-registration to complete successfully, otherwise the driver
leaves wild pointers to invalid data structures and thus leading to a panic.