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| author | Peter Maydell <peter.maydell@linaro.org> | 2022-07-19 17:40:36 +0100 |
|---|---|---|
| committer | Peter Maydell <peter.maydell@linaro.org> | 2022-07-19 17:40:36 +0100 |
| commit | d48125de38f48a61d6423ef6a01156d6dff9ee2c (patch) | |
| tree | f1555f3565dcb7f00a4ba7a6b581700516b720a6 /docs | |
| parent | da7da9d5e608200ecc0749ff37be246e9cd3314f (diff) | |
| parent | c34a933802071aae5288e0aa3792756312e3da34 (diff) | |
Merge tag 'kraxel-20220719-pull-request' of https://gitlab.com/kraxel/qemu into staging
ui: dbus-display fix, new gtk config options.
usb: xhci fix, doc updates.
microvm: no pcie io reservations.
# gpg: Signature made Tue 19 Jul 2022 16:21:06 BST
# gpg: using RSA key A0328CFFB93A17A79901FE7D4CB6D8EED3E87138
# gpg: Good signature from "Gerd Hoffmann (work) <kraxel@redhat.com>" [full]
# gpg: aka "Gerd Hoffmann <gerd@kraxel.org>" [full]
# gpg: aka "Gerd Hoffmann (private) <kraxel@gmail.com>" [full]
# Primary key fingerprint: A032 8CFF B93A 17A7 9901 FE7D 4CB6 D8EE D3E8 7138
* tag 'kraxel-20220719-pull-request' of https://gitlab.com/kraxel/qemu:
gtk: Add show_tabs=on|off command line option.
usb: document pcap (aka usb traffic capture)
usb: document guest-reset and guest-reset-all
usb/hcd-xhci: check slotid in xhci_wakeup_endpoint()
microvm: turn off io reservations for pcie root ports
dbus-display: fix test race when initializing p2p connection
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Diffstat (limited to 'docs')
| -rw-r--r-- | docs/system/devices/usb.rst | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/docs/system/devices/usb.rst b/docs/system/devices/usb.rst index 872d916758..f39a88f080 100644 --- a/docs/system/devices/usb.rst +++ b/docs/system/devices/usb.rst @@ -353,3 +353,44 @@ and also assign it to the correct USB bus in QEMU like this: -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 + +``usb-host`` properties for reset behavior +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +The ``guest-reset`` and ``guest-reset-all`` properties control +whenever the guest is allowed to reset the physical usb device on the +host. There are three cases: + +``guest-reset=false`` + The guest is not allowed to reset the (physical) usb device. + +``guest-reset=true,guest-resets-all=false`` + The guest is allowed to reset the device when it is not yet + initialized (aka no usb bus address assigned). Usually this results + in one guest reset being allowed. This is the default behavior. + +``guest-reset=true,guest-resets-all=true`` + The guest is allowed to reset the device as it pleases. + +The reason for this existing are broken usb devices. In theory one +should be able to reset (and re-initialize) usb devices at any time. +In practice that may result in shitty usb device firmware crashing and +the device not responding any more until you power-cycle (aka un-plug +and re-plug) it. + +What works best pretty much depends on the behavior of the specific +usb device at hand, so it's a trial-and-error game. If the default +doesn't work, try another option and see whenever the situation +improves. + +record usb transfers +^^^^^^^^^^^^^^^^^^^^ + +All usb devices have support for recording the usb traffic. This can +be enabled using the ``pcap=<file>`` property, for example: + +``-device usb-mouse,pcap=mouse.pcap`` + +The pcap files are compatible with the linux kernels usbmon. Many +tools, including ``wireshark``, can decode and inspect these trace +files. |