1.\" $NetBSD: uaudio.4,v 1.15 2002/02/12 19:53:57 jdolecek Exp $ 2.\" 3.\" Copyright (c) 1999 The NetBSD Foundation, Inc. 4.\" All rights reserved. 5.\" 6.\" This code is derived from software contributed to The NetBSD Foundation 7.\" by Lennart Augustsson. 8.\" 9.\" Redistribution and use in source and binary forms, with or without 10.\" modification, are permitted provided that the following conditions 11.\" are met: 12.\" 1. Redistributions of source code must retain the above copyright 13.\" notice, this list of conditions and the following disclaimer. 14.\" 2. Redistributions in binary form must reproduce the above copyright 15.\" notice, this list of conditions and the following disclaimer in the 16.\" documentation and/or other materials provided with the distribution. 17.\" 3. All advertising materials mentioning features or use of this software 18.\" must display the following acknowledgement: 19.\" This product includes software developed by the NetBSD 20.\" Foundation, Inc. and its contributors. 21.\" 4. Neither the name of The NetBSD Foundation nor the names of its 22.\" contributors may be used to endorse or promote products derived 23.\" from this software without specific prior written permission. 24.\" 25.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 26.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 27.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 28.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 29.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 30.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 31.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 32.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 33.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 34.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 35.\" POSSIBILITY OF SUCH DAMAGE. 36.\" 37.\" $FreeBSD$ 38.\" 39.Dd December 15, 2005 40.Dt SND_UAUDIO 4 41.Os 42.Sh NAME 43.Nm snd_uaudio 44.Nd USB audio device driver 45.Sh SYNOPSIS 46To compile this driver into the kernel, place the following lines in your 47kernel configuration file: 48.Bd -ragged -offset indent 49.Cd "device sound" 50.Cd "device usb" 51.Cd "device snd_uaudio" 52.Ed 53.Pp 54Alternatively, to load the driver as a module at boot time, place the 55following line in 56.Xr loader.conf 5 : 57.Bd -literal -offset indent 58snd_uaudio_load="YES" 59.Ed 60.Sh DESCRIPTION 61The 62.Nm 63driver provides support for 64.Tn USB 65audio class devices. 66.Pp 67A 68.Tn USB 69audio device consists of a number of components: 70input terminals (e.g.\& USB digital input), output terminals (e.g.\& 71speakers), and a number of units in between (e.g.\& volume control). 72.Pp 73Refer to the 74.Ql USB Audio Class Specification 75for more information. 76.Sh SEE ALSO 77.Xr sound 4 , 78.Xr usb 4 79.Rs 80.%T "USB Audio Class Specifications" 81.%O http://www.usb.org/developers/devclass_docs/ 82.Re 83.Sh HISTORY 84The 85.Nm 86driver first appeared in 87.Fx 4.7 . 88.Sh AUTHORS 89This manual page was adopted from 90.Nx 1.6 91and modified for 92.Fx 93by 94.An Hiten Pandya Aq hmp@FreeBSD.org . 95.Sh BUGS 96The 97.Tn PCM 98framework in 99.Fx , 100as of this writing, does not handle device un-registrations in a properly 101abstracted manner, i.e., a detach request is refused by the 102.Tn PCM 103framework if the device is in use. 104For 105.Tn USB 106and supposedly other detach-able busses, it is necessary to allow the 107device un-registration to complete successfully, otherwise the driver 108leaves wild pointers to invalid data structures and thus leading to a panic. 109