This adds basic documentation for vhost-user-input.
Signed-off-by: Leo Yan <leo....@linaro.org>
---
docs/system/devices/vhost-user-input.rst | 44 ++++++++++++++++++++++++
docs/system/devices/vhost-user.rst | 2 +-
2 files changed, 45 insertions(+), 1 deletion(-)
create mode 100644 docs/system/devices/vhost-user-input.rst
diff --git a/docs/system/devices/vhost-user-input.rst
b/docs/system/devices/vhost-user-input.rst
new file mode 100644
index 0000000000..601282e658
--- /dev/null
+++ b/docs/system/devices/vhost-user-input.rst
@@ -0,0 +1,44 @@
+.. _vhost_user_rng:
+
+QEMU vhost-user-input - Input emulation
+=======================================
+
+This document describes the setup and usage of the Virtio input device.
+The Virtio input device is a paravirtualized device for input events.
+
+Description
+-----------
+
+The vhost-user-input device implementation was designed to work with a daemon
+polling on input devices and passes input events to the guest.
+
+QEMU provides a backend implementation in contrib/vhost-user-input.
+
+Linux kernel support
+--------------------
+
+Virtio input requires a guest Linux kernel built with the
+``CONFIG_VIRTIO_INPUT`` option.
+
+Examples
+--------
+
+The backend daemon should be started first:
+
+::
+
+ host# vhost-user-input --socket-path=input.sock \
+ --evdev-path=/dev/input/event17
+
+The QEMU invocation needs to create a chardev socket to communicate with the
+backend daemon and share memory with the guest over a memfd.
+
+::
+
+ host# qemu-system
\
+ -chardev socket,path=/tmp/input.sock,id=mouse0
\
+ -device vhost-user-input-pci,chardev=mouse0
\
+ -m 4096
\
+ -object memory-backend-file,id=mem,size=4G,mem-path=/dev/shm,share=on
\
+ -numa node,memdev=mem
\
+ ...
diff --git a/docs/system/devices/vhost-user.rst
b/docs/system/devices/vhost-user.rst
index c6afc4836f..75b40f08c6 100644
--- a/docs/system/devices/vhost-user.rst
+++ b/docs/system/devices/vhost-user.rst
@@ -42,7 +42,7 @@ platform details for what sort of virtio bus to use.
- See https://github.com/rust-vmm/vhost-device
* - vhost-user-input
- Generic input driver
- - See contrib/vhost-user-input
+ - :ref:`vhost_user_input`
* - vhost-user-rng
- Entropy driver
- :ref:`vhost_user_rng`
--
2.34.1
