f54fea113c
This commit adds basic documentation for using virtio-snd. Signed-off-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org> Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Tested-by: Alex Bennée <alex.bennee@linaro.org> Message-Id: <e7fb941cf7636fdff40cbdcdcd660dec5f15ca3c.1698062525.git.manos.pitsidianakis@linaro.org> Acked-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
50 lines
1.6 KiB
ReStructuredText
50 lines
1.6 KiB
ReStructuredText
virtio sound
|
|
============
|
|
|
|
This document explains the setup and usage of the Virtio sound device.
|
|
The Virtio sound device is a paravirtualized sound card device.
|
|
|
|
Linux kernel support
|
|
--------------------
|
|
|
|
Virtio sound requires a guest Linux kernel built with the
|
|
``CONFIG_SND_VIRTIO`` option.
|
|
|
|
Description
|
|
-----------
|
|
|
|
Virtio sound implements capture and playback from inside a guest using the
|
|
configured audio backend of the host machine.
|
|
|
|
Device properties
|
|
-----------------
|
|
|
|
The Virtio sound device can be configured with the following properties:
|
|
|
|
* ``jacks`` number of physical jacks (Unimplemented).
|
|
* ``streams`` number of PCM streams. At the moment, no stream configuration is supported: the first one will always be a playback stream, an optional second will always be a capture stream. Adding more will cycle stream directions from playback to capture.
|
|
* ``chmaps`` number of channel maps (Unimplemented).
|
|
|
|
All streams are stereo and have the default channel positions ``Front left, right``.
|
|
|
|
Examples
|
|
--------
|
|
|
|
Add an audio device and an audio backend at once with ``-audio`` and ``model=virtio``:
|
|
|
|
* pulseaudio: ``-audio driver=pa,model=virtio``
|
|
or ``-audio driver=pa,model=virtio,server=/run/user/1000/pulse/native``
|
|
* sdl: ``-audio driver=sdl,model=virtio``
|
|
* coreaudio: ``-audio driver=coreaudio,model=virtio``
|
|
|
|
etc.
|
|
|
|
To specifically add virtualized sound devices, you have to specify a PCI device
|
|
and an audio backend listed with ``-audio driver=help`` that works on your host
|
|
machine, e.g.:
|
|
|
|
::
|
|
|
|
-device virtio-sound-pci,audiodev=my_audiodev \
|
|
-audiodev alsa,id=my_audiodev
|