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The workspace section in Rust documentation suggests adding new crates in the top level directory itself instead of the src folder. Remove the top level src folder. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
65 lines
1.8 KiB
Markdown
65 lines
1.8 KiB
Markdown
# vhost-device-i2c - I2C emulation backend daemon
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## Description
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This program is a vhost-user backend that emulates a VirtIO I2C bus.
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This program takes the layout of the i2c bus and its devices on the host
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OS and then talks to them via the /dev/i2c-X interface when a request
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comes from the guest OS for an I2C or SMBUS device.
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This program is tested with QEMU's `-device vhost-user-i2c-pci` but should
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work with any virtual machine monitor (VMM) that supports vhost-user. See the
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Examples section below.
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## Synopsis
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**vhost-device-i2c** [*OPTIONS*]
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## Options
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.. program:: vhost-device-i2c
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.. option:: -h, --help
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Print help.
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.. option:: -s, --socket-path=PATH
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Location of vhost-user Unix domain sockets, this path will be suffixed with
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0,1,2..socket_count-1.
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.. option:: -c, --socket-count=INT
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Number of guests (sockets) to attach to, default set to 1.
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.. option:: -l, --device-list=I2C-DEVICES
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I2c device list at the host OS in the format:
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<bus>:<client_addr>[:<client_addr>],[<bus>:<client_addr>[:<client_addr>]]
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Example: --device-list "2:32:21,3:10:23"
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Here,
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bus (decimal): adatper bus number. e.g. 2 for /dev/i2c-2, 3 for /dev/i2c-3.
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client_addr (decimal): address for client device, 32 == 0x20.
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## Examples
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The daemon should be started first:
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::
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host# vhost-device-i2c --socket-path=vi2c.sock --socket-count=1 --device-list 0:32
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The QEMU invocation needs to create a chardev socket the device can
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use to communicate as well as share the guests memory over a memfd.
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::
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host# qemu-system \
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-chardev socket,path=vi2c.sock,id=vi2c \
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-device vhost-user-i2c-pci,chardev=vi2c,id=i2c \
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-m 4096 \
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-object memory-backend-file,id=mem,size=4G,mem-path=/dev/shm,share=on \
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-numa node,memdev=mem \
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...
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