1 .\" $NetBSD: ac97.4,v 1.1 2005/06/21 18:11:38 wiz Exp $
2 .\" $OpenBSD: ac97.4,v 1.12 2003/02/18 07:54:53 jmc Exp $
4 .\" Copyright (c) 1999, 2000 Constantine Sapuntzakis
6 .\" Author: Constantine Sapuntzakis <csapuntz@stanford.edu>
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37 .Nd generic AC97 codec driver
39 AC97 codecs contain the analog-to-digital (A/D), digital-to-analog
40 (D/A), and mixing circuitry of many modern sound cards.
41 AC97 codecs, for the most part, do not talk to host busses like the PCI bus
43 Instead, they communicate through an interface chip, called
45 The Ensoniq AudioPCI 97 (see
47 is an example of such a host controller.
49 Unlike many drivers, the
51 driver does not appear in the configuration file.
52 Instead, the driver is automatically attached by the drivers that require it.
72 driver does not keep track of the current user settings and instead
73 relies on the hardware to do this.
77 driver could do more to detect mixer channels that don't work and cull