Fold the usb2.txt information on device passthrough into usb.rst; since this is the last part of the .txt file we can delete it now. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Message-Id: <20210728141457.14825-5-peter.maydell@linaro.org> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
352 lines
13 KiB
ReStructuredText
352 lines
13 KiB
ReStructuredText
.. _pcsys_005fusb:
|
|
|
|
USB emulation
|
|
-------------
|
|
|
|
QEMU can emulate a PCI UHCI, OHCI, EHCI or XHCI USB controller. You can
|
|
plug virtual USB devices or real host USB devices (only works with
|
|
certain host operating systems). QEMU will automatically create and
|
|
connect virtual USB hubs as necessary to connect multiple USB devices.
|
|
|
|
USB controllers
|
|
~~~~~~~~~~~~~~~
|
|
|
|
XHCI controller support
|
|
^^^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
QEMU has XHCI host adapter support. The XHCI hardware design is much
|
|
more virtualization-friendly when compared to EHCI and UHCI, thus XHCI
|
|
emulation uses less resources (especially CPU). So if your guest
|
|
supports XHCI (which should be the case for any operating system
|
|
released around 2010 or later) we recommend using it:
|
|
|
|
qemu -device qemu-xhci
|
|
|
|
XHCI supports USB 1.1, USB 2.0 and USB 3.0 devices, so this is the
|
|
only controller you need. With only a single USB controller (and
|
|
therefore only a single USB bus) present in the system there is no
|
|
need to use the bus= parameter when adding USB devices.
|
|
|
|
|
|
EHCI controller support
|
|
^^^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
The QEMU EHCI Adapter supports USB 2.0 devices. It can be used either
|
|
standalone or with companion controllers (UHCI, OHCI) for USB 1.1
|
|
devices. The companion controller setup is more convenient to use
|
|
because it provides a single USB bus supporting both USB 2.0 and USB
|
|
1.1 devices. See next section for details.
|
|
|
|
When running EHCI in standalone mode you can add UHCI or OHCI
|
|
controllers for USB 1.1 devices too. Each controller creates its own
|
|
bus though, so there are two completely separate USB buses: One USB
|
|
1.1 bus driven by the UHCI controller and one USB 2.0 bus driven by
|
|
the EHCI controller. Devices must be attached to the correct
|
|
controller manually.
|
|
|
|
The easiest way to add a UHCI controller to a ``pc`` machine is the
|
|
``-usb`` switch. QEMU will create the UHCI controller as function of
|
|
the PIIX3 chipset. The USB 1.1 bus will carry the name ``usb-bus.0``.
|
|
|
|
You can use the standard ``-device`` switch to add a EHCI controller to
|
|
your virtual machine. It is strongly recommended to specify an ID for
|
|
the controller so the USB 2.0 bus gets an individual name, for example
|
|
``-device usb-ehci,id=ehci``. This will give you a USB 2.0 bus named
|
|
``ehci.0``.
|
|
|
|
When adding USB devices using the ``-device`` switch you can specify the
|
|
bus they should be attached to. Here is a complete example:
|
|
|
|
.. parsed-literal::
|
|
|
|
|qemu_system| -M pc ${otheroptions} \\
|
|
-drive if=none,id=usbstick,format=raw,file=/path/to/image \\
|
|
-usb \\
|
|
-device usb-ehci,id=ehci \\
|
|
-device usb-tablet,bus=usb-bus.0 \\
|
|
-device usb-storage,bus=ehci.0,drive=usbstick
|
|
|
|
This attaches a USB tablet to the UHCI adapter and a USB mass storage
|
|
device to the EHCI adapter.
|
|
|
|
|
|
Companion controller support
|
|
^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
The UHCI and OHCI controllers can attach to a USB bus created by EHCI
|
|
as companion controllers. This is done by specifying the ``masterbus``
|
|
and ``firstport`` properties. ``masterbus`` specifies the bus name the
|
|
controller should attach to. ``firstport`` specifies the first port the
|
|
controller should attach to, which is needed as usually one EHCI
|
|
controller with six ports has three UHCI companion controllers with
|
|
two ports each.
|
|
|
|
There is a config file in docs which will do all this for
|
|
you, which you can use like this:
|
|
|
|
.. parsed-literal::
|
|
|
|
|qemu_system| -readconfig docs/config/ich9-ehci-uhci.cfg
|
|
|
|
Then use ``bus=ehci.0`` to assign your USB devices to that bus.
|
|
|
|
Using the ``-usb`` switch for ``q35`` machines will create a similar
|
|
USB controller configuration.
|
|
|
|
|
|
.. _Connecting USB devices:
|
|
|
|
Connecting USB devices
|
|
~~~~~~~~~~~~~~~~~~~~~~
|
|
|
|
USB devices can be connected with the ``-device usb-...`` command line
|
|
option or the ``device_add`` monitor command. Available devices are:
|
|
|
|
``usb-mouse``
|
|
Virtual Mouse. This will override the PS/2 mouse emulation when
|
|
activated.
|
|
|
|
``usb-tablet``
|
|
Pointer device that uses absolute coordinates (like a touchscreen).
|
|
This means QEMU is able to report the mouse position without having
|
|
to grab the mouse. Also overrides the PS/2 mouse emulation when
|
|
activated.
|
|
|
|
``usb-storage,drive=drive_id``
|
|
Mass storage device backed by drive_id (see the :ref:`disk images`
|
|
chapter in the System Emulation Users Guide). This is the classic
|
|
bulk-only transport protocol used by 99% of USB sticks. This
|
|
example shows it connected to an XHCI USB controller and with
|
|
a drive backed by a raw format disk image:
|
|
|
|
.. parsed-literal::
|
|
|
|
|qemu_system| [...] \\
|
|
-drive if=none,id=stick,format=raw,file=/path/to/file.img \\
|
|
-device nec-usb-xhci,id=xhci \\
|
|
-device usb-storage,bus=xhci.0,drive=stick
|
|
|
|
``usb-uas``
|
|
USB attached SCSI device. This does not create a SCSI disk, so
|
|
you need to explicitly create a ``scsi-hd`` or ``scsi-cd`` device
|
|
on the command line, as well as using the ``-drive`` option to
|
|
specify what those disks are backed by. One ``usb-uas`` device can
|
|
handle multiple logical units (disks). This example creates three
|
|
logical units: two disks and one cdrom drive:
|
|
|
|
.. parsed-literal::
|
|
|
|
|qemu_system| [...] \\
|
|
-drive if=none,id=uas-disk1,format=raw,file=/path/to/file1.img \\
|
|
-drive if=none,id=uas-disk2,format=raw,file=/path/to/file2.img \\
|
|
-drive if=none,id=uas-cdrom,media=cdrom,format=raw,file=/path/to/image.iso \\
|
|
-device nec-usb-xhci,id=xhci \\
|
|
-device usb-uas,id=uas,bus=xhci.0 \\
|
|
-device scsi-hd,bus=uas.0,scsi-id=0,lun=0,drive=uas-disk1 \\
|
|
-device scsi-hd,bus=uas.0,scsi-id=0,lun=1,drive=uas-disk2 \\
|
|
-device scsi-cd,bus=uas.0,scsi-id=0,lun=5,drive=uas-cdrom
|
|
|
|
``usb-bot``
|
|
Bulk-only transport storage device. This presents the guest with the
|
|
same USB bulk-only transport protocol interface as ``usb-storage``, but
|
|
the QEMU command line option works like ``usb-uas`` and does not
|
|
automatically create SCSI disks for you. ``usb-bot`` supports up to
|
|
16 LUNs. Unlike ``usb-uas``, the LUN numbers must be continuous,
|
|
i.e. for three devices you must use 0+1+2. The 0+1+5 numbering from the
|
|
``usb-uas`` example above won't work with ``usb-bot``.
|
|
|
|
``usb-mtp,rootdir=dir``
|
|
Media transfer protocol device, using dir as root of the file tree
|
|
that is presented to the guest.
|
|
|
|
``usb-host,hostbus=bus,hostaddr=addr``
|
|
Pass through the host device identified by bus and addr
|
|
|
|
``usb-host,vendorid=vendor,productid=product``
|
|
Pass through the host device identified by vendor and product ID
|
|
|
|
``usb-wacom-tablet``
|
|
Virtual Wacom PenPartner tablet. This device is similar to the
|
|
``tablet`` above but it can be used with the tslib library because in
|
|
addition to touch coordinates it reports touch pressure.
|
|
|
|
``usb-kbd``
|
|
Standard USB keyboard. Will override the PS/2 keyboard (if present).
|
|
|
|
``usb-serial,chardev=id``
|
|
Serial converter. This emulates an FTDI FT232BM chip connected to
|
|
host character device id.
|
|
|
|
``usb-braille,chardev=id``
|
|
Braille device. This will use BrlAPI to display the braille output on
|
|
a real or fake device referenced by id.
|
|
|
|
``usb-net[,netdev=id]``
|
|
Network adapter that supports CDC ethernet and RNDIS protocols. id
|
|
specifies a netdev defined with ``-netdev …,id=id``. For instance,
|
|
user-mode networking can be used with
|
|
|
|
.. parsed-literal::
|
|
|
|
|qemu_system| [...] -netdev user,id=net0 -device usb-net,netdev=net0
|
|
|
|
``usb-ccid``
|
|
Smartcard reader device
|
|
|
|
``usb-audio``
|
|
USB audio device
|
|
|
|
``u2f-{emulated,passthru}``
|
|
Universal Second Factor device
|
|
|
|
Physical port addressing
|
|
^^^^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
For all the above USB devices, by default QEMU will plug the device
|
|
into the next available port on the specified USB bus, or onto
|
|
some available USB bus if you didn't specify one explicitly.
|
|
If you need to, you can also specify the physical port where
|
|
the device will show up in the guest. This can be done using the
|
|
``port`` property. UHCI has two root ports (1,2). EHCI has six root
|
|
ports (1-6), and the emulated (1.1) USB hub has eight ports.
|
|
|
|
Plugging a tablet into UHCI port 1 works like this::
|
|
|
|
-device usb-tablet,bus=usb-bus.0,port=1
|
|
|
|
Plugging a hub into UHCI port 2 works like this::
|
|
|
|
-device usb-hub,bus=usb-bus.0,port=2
|
|
|
|
Plugging a virtual USB stick into port 4 of the hub just plugged works
|
|
this way::
|
|
|
|
-device usb-storage,bus=usb-bus.0,port=2.4,drive=...
|
|
|
|
In the monitor, the ``device_add` command also accepts a ``port``
|
|
property specification. If you want to unplug devices too you should
|
|
specify some unique id which you can use to refer to the device.
|
|
You can then use ``device_del`` to unplug the device later.
|
|
For example::
|
|
|
|
(qemu) device_add usb-tablet,bus=usb-bus.0,port=1,id=my-tablet
|
|
(qemu) device_del my-tablet
|
|
|
|
Hotplugging USB storage
|
|
~~~~~~~~~~~~~~~~~~~~~~~
|
|
|
|
The ``usb-bot`` and ``usb-uas`` devices can be hotplugged. In the hotplug
|
|
case they are added with ``attached = false`` so the guest will not see
|
|
the device until the ``attached`` property is explicitly set to true.
|
|
That allows you to attach one or more scsi devices before making the
|
|
device visible to the guest. The workflow looks like this:
|
|
|
|
#. ``device-add usb-bot,id=foo``
|
|
#. ``device-add scsi-{hd,cd},bus=foo.0,lun=0``
|
|
#. optionally add more devices (luns 1 ... 15)
|
|
#. ``scripts/qmp/qom-set foo.attached = true``
|
|
|
|
.. _host_005fusb_005fdevices:
|
|
|
|
Using host USB devices on a Linux host
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
|
|
WARNING: this is an experimental feature. QEMU will slow down when using
|
|
it. USB devices requiring real time streaming (i.e. USB Video Cameras)
|
|
are not supported yet.
|
|
|
|
1. If you use an early Linux 2.4 kernel, verify that no Linux driver is
|
|
actually using the USB device. A simple way to do that is simply to
|
|
disable the corresponding kernel module by renaming it from
|
|
``mydriver.o`` to ``mydriver.o.disabled``.
|
|
|
|
2. Verify that ``/proc/bus/usb`` is working (most Linux distributions
|
|
should enable it by default). You should see something like that:
|
|
|
|
::
|
|
|
|
ls /proc/bus/usb
|
|
001 devices drivers
|
|
|
|
3. Since only root can access to the USB devices directly, you can
|
|
either launch QEMU as root or change the permissions of the USB
|
|
devices you want to use. For testing, the following suffices:
|
|
|
|
::
|
|
|
|
chown -R myuid /proc/bus/usb
|
|
|
|
4. Launch QEMU and do in the monitor:
|
|
|
|
::
|
|
|
|
info usbhost
|
|
Device 1.2, speed 480 Mb/s
|
|
Class 00: USB device 1234:5678, USB DISK
|
|
|
|
You should see the list of the devices you can use (Never try to use
|
|
hubs, it won't work).
|
|
|
|
5. Add the device in QEMU by using:
|
|
|
|
::
|
|
|
|
device_add usb-host,vendorid=0x1234,productid=0x5678
|
|
|
|
Normally the guest OS should report that a new USB device is plugged.
|
|
You can use the option ``-device usb-host,...`` to do the same.
|
|
|
|
6. Now you can try to use the host USB device in QEMU.
|
|
|
|
When relaunching QEMU, you may have to unplug and plug again the USB
|
|
device to make it work again (this is a bug).
|
|
|
|
``usb-host`` properties for specifying the host device
|
|
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
The example above uses the ``vendorid`` and ``productid`` to
|
|
specify which host device to pass through, but this is not
|
|
the only way to specify the host device. ``usb-host`` supports
|
|
the following properties:
|
|
|
|
``hostbus=<nr>``
|
|
Specifies the bus number the device must be attached to
|
|
``hostaddr=<nr>``
|
|
Specifies the device address the device got assigned by the guest os
|
|
``hostport=<str>``
|
|
Specifies the physical port the device is attached to
|
|
``vendorid=<hexnr>``
|
|
Specifies the vendor ID of the device
|
|
``productid=<hexnr>``
|
|
Specifies the product ID of the device.
|
|
|
|
In theory you can combine all these properties as you like. In
|
|
practice only a few combinations are useful:
|
|
|
|
- ``vendorid`` and ``productid`` -- match for a specific device, pass it to
|
|
the guest when it shows up somewhere in the host.
|
|
|
|
- ``hostbus`` and ``hostport`` -- match for a specific physical port in the
|
|
host, any device which is plugged in there gets passed to the
|
|
guest.
|
|
|
|
- ``hostbus`` and ``hostaddr`` -- most useful for ad-hoc pass through as the
|
|
hostaddr isn't stable. The next time you plug the device into the host it
|
|
will get a new hostaddr.
|
|
|
|
Note that on the host USB 1.1 devices are handled by UHCI/OHCI and USB
|
|
2.0 by EHCI. That means different USB devices plugged into the very
|
|
same physical port on the host may show up on different host buses
|
|
depending on the speed. Supposing that devices plugged into a given
|
|
physical port appear as bus 1 + port 1 for 2.0 devices and bus 3 + port 1
|
|
for 1.1 devices, you can pass through any device plugged into that port
|
|
and also assign it to the correct USB bus in QEMU like this:
|
|
|
|
.. parsed-literal::
|
|
|
|
|qemu_system| -M pc [...] \\
|
|
-usb \\
|
|
-device usb-ehci,id=ehci \\
|
|
-device usb-host,bus=usb-bus.0,hostbus=3,hostport=1 \\
|
|
-device usb-host,bus=ehci.0,hostbus=1,hostport=1
|