new file mode 100644
@@ -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 \
+ ...
@@ -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`
This adds basic documentation for vhost-user-input. Signed-off-by: Leo Yan <leo.yan@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