From f54fea113cc48000836b95681f3b9fdbe43c7d96 Mon Sep 17 00:00:00 2001 From: Manos Pitsidianakis Date: Mon, 23 Oct 2023 15:03:28 +0300 Subject: [PATCH] docs/system: add basic virtio-snd documentation MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This commit adds basic documentation for using virtio-snd. Signed-off-by: Manos Pitsidianakis Reviewed-by: Alex Bennée Tested-by: Alex Bennée Message-Id: Acked-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- MAINTAINERS | 1 + docs/system/device-emulation.rst | 1 + docs/system/devices/virtio-snd.rst | 49 ++++++++++++++++++++++++++++++ 3 files changed, 51 insertions(+) create mode 100644 docs/system/devices/virtio-snd.rst diff --git a/MAINTAINERS b/MAINTAINERS index c09bb8cf41..4fad272d73 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -2317,6 +2317,7 @@ S: Supported F: hw/audio/virtio-snd.c F: hw/audio/virtio-snd-pci.c F: include/hw/audio/virtio-snd.h +F: docs/system/devices/virtio-snd.rst nvme M: Keith Busch diff --git a/docs/system/device-emulation.rst b/docs/system/device-emulation.rst index 1167f3a9f2..d1f3277cb0 100644 --- a/docs/system/device-emulation.rst +++ b/docs/system/device-emulation.rst @@ -93,6 +93,7 @@ Emulated Devices devices/vhost-user.rst devices/virtio-gpu.rst devices/virtio-pmem.rst + devices/virtio-snd.rst devices/vhost-user-rng.rst devices/canokey.rst devices/usb-u2f.rst diff --git a/docs/system/devices/virtio-snd.rst b/docs/system/devices/virtio-snd.rst new file mode 100644 index 0000000000..2a9187fd70 --- /dev/null +++ b/docs/system/devices/virtio-snd.rst @@ -0,0 +1,49 @@ +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