NAME
snd_maestro3
—
ESS Maestro3/Allegro-1 bridge device
driver
SYNOPSIS
To compile this driver into the kernel, place the following lines in your kernel configuration file:
device sound
device snd_maestro3
Alternatively, to load the driver as a module at boot time, place the following line in loader.conf(5):
snd_maestro3_load="YES"
DESCRIPTION
Thesnd_maestro3
driver provides support for the ESS
Maestro3 and Allegro-1 sound chips under the PCM framework. These chips are
mostly found in laptop computers and feature an AC97 mixer, a multi-channel
sample rate converter that can mix up to four digital audio streams in
hardware, recording support, and external volume control buttons.
The firmware for the sound processor is licensed under the GNU Public License, and thus this driver is not included in the default GENERIC kernel.
HARDWARE
The snd_maestro3
driver supports the
following audio devices:
- ESS Technology Allegro-1
- ESS Technology Maestro3
DIAGNOSTICS
The hardware volume control buttons can be connected to two
different pin sets (GPIO or GD) on the chip, depending on the manufacturer.
The driver has no way of determining this configuration, so a hint may be
used to override the default guess. The default setting for hardware volume
control assumes that GD pins are wired to control the hardware volume. For
systems that have the GPIO pins wired to the hardware volume control
buttons, add the line
“hint.pcm.0.hwvol_config="0"
”
to the file /boot/device.hints to override the
default setting.
SEE ALSO
HISTORY
The snd_maestro3
driver first appeared in
FreeBSD 4.3.
AUTHORS
Scott Long
<scottl@FreeBSD.org>
Darrel Anderson
<anderson@cs.duke.edu>