Module Name: src
Committed By: nia
Date: Thu May 16 17:00:32 UTC 2024
Modified Files:
src/share/man/man4: eap.4
Log Message:
add additional details about how EAP_USE_BOTH_DACS works and is used
requested by uwe
To generate a diff of this commit:
cvs rdiff -u -r1.19 -r1.20 src/share/man/man4/eap.4
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/share/man/man4/eap.4
diff -u src/share/man/man4/eap.4:1.19 src/share/man/man4/eap.4:1.20
--- src/share/man/man4/eap.4:1.19 Thu May 16 14:41:03 2024
+++ src/share/man/man4/eap.4 Thu May 16 17:00:31 2024
@@ -1,4 +1,4 @@
-.\" $NetBSD: eap.4,v 1.19 2024/05/16 14:41:03 uwe Exp $
+.\" $NetBSD: eap.4,v 1.20 2024/05/16 17:00:31 nia Exp $
.\"
.\" Copyright (c) 1999 The NetBSD Foundation, Inc.
.\" All rights reserved.
@@ -52,7 +52,10 @@ By specifying:
.D1 Cd options EAP_USE_BOTH_DACS
.Pp
a second audio device is attached.
-You can use it simply by directing audio output to it.
+This can be used for audio output simultaneously with the primary DAC.
+You can use it simply by directing audio output to the additional
+.Pa /dev/audioX
+device associated with it.
.Sh SEE ALSO
.Xr ac97 4 ,
.Xr audio 4 ,
@@ -79,3 +82,13 @@ The
.Dv EAP_USE_BOTH_DACS
option is rather redundant after the introduction of the in-kernel audio
mixer, and may be removed in a future release.
+It is possible that it could be used to accelerate mixing streams by
+taking advantage of the hardware's features, but currently the
+additional (small) overhead of the kernel mixer is impossible to bypass,
+since
+.Nx
+no longer allows userspace software to write directly to audio hardware.
+The
+.Nm
+hardware only features one clock, so generally the second audio device
+must be configured in the same way as the first.
