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Diffstat (limited to 'docs/usb2.txt')
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diff --git a/docs/usb2.txt b/docs/usb2.txt new file mode 100644 index 0000000000..b283c138e0 --- /dev/null +++ b/docs/usb2.txt @@ -0,0 +1,38 @@ + +USB 2.0 Quick Start +=================== + +The QEMU EHCI Adapter does *not* support companion controllers. That +implies there are two completely separate USB busses: 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 '-usb' switch will make qemu create the UHCI controller as part of +the PIIX3 chipset. The USB 1.1 bus will carry the name "usb.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 a individual name, for example +'-device usb-ehci,id=ehci". This will give you a USB 2.0 bus named +"ehci.0". + +I strongly recomment to also use -device to attach usb devices because +you can specify the bus they should be attached to this way. Here is +a complete example: + + qemu -M pc ${otheroptions} \ + -drive if=none,id=usbstick,file=/path/to/image \ + -usb \ + -device usb-ehci,id=ehci \ + -device usb-tablet,bus=usb.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. + +enjoy, + Gerd + +-- +Gerd Hoffmann <kraxel@redhat.com> |