Module Name: src
Committed By: martin
Date: Mon Jun 17 18:03:43 UTC 2024
Modified Files:
src/share/man/man4 [netbsd-9]: eap.4
Log Message:
Pull up following revision(s) (requested by nia in ticket #1844):
share/man/man4/eap.4: revision 1.20
share/man/man4/eap.4: revision 1.18
share/man/man4/eap.4: revision 1.19
Note that EAP_USE_BOTH_DACS is deprecated in the eap(4) manual page.
eap(4): touch up markup a bit
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 -r1.17 -r1.17.66.1 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.4:1.17 src/share/man/man4/eap.4:1.17.66.1
--- src/share/man/man4/eap.4:1.17 Wed Apr 30 13:10:53 2008
+++ src/share/man/man4/eap.4 Mon Jun 17 18:03:43 2024
@@ -1,4 +1,4 @@
-.\" $NetBSD: eap.4,v 1.17 2008/04/30 13:10:53 martin Exp $
+.\" $NetBSD: eap.4,v 1.17.66.1 2024/06/17 18:03:43 martin Exp $
.\"
.\" Copyright (c) 1999 The NetBSD Foundation, Inc.
.\" All rights reserved.
@@ -27,18 +27,19 @@
.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
.\" POSSIBILITY OF SUCH DAMAGE.
.\"
-.Dd July 22, 2006
+.Dd May 16, 2024
.Dt EAP 4
.Os
.Sh NAME
.Nm eap
.Nd AudioPCI audio device driver
.Sh SYNOPSIS
-.Cd "eap* at pci? dev ? function ?"
-.Cd "audio* at audiobus?"
-.Cd "joy* at eap?"
-.Cd "midi* at eap?"
+.Cd "eap* at pci? dev ? function ?"
.Cd "options EAP_USE_BOTH_DACS"
+.Pp
+.Cd "audio* at audiobus?"
+.Cd "joy* at eap?"
+.Cd "midi* at eap?"
.Sh DESCRIPTION
The
.Nm
@@ -47,14 +48,14 @@ SoundBlaster PCI series of audio cards.
All models based on the ES1370, ES1371, and ES1373 chips are supported.
.Pp
By specifying:
-.Bd -unfilled -offset indent
-options EAP_USE_BOTH_DACS
-.Ed
+.Pp
+.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 way it is possible for two different programs to use the "same"
-audio device simultaneously.
+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 ,
@@ -76,3 +77,18 @@ This is unlikely to work on PCI busses o
There is also a possibility for conflicts with real ISA devices
because the PCI bus is probed before ISA.
Use with caution.
+.Pp
+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.
