docs/usb2.txt

   1
   2 USB 2.0 Quick Start
   3 ===================
   4
   5 The QEMU EHCI Adapter does *not* support companion controllers.  That
   6 implies there are two completely separate USB busses: One USB 1.1 bus
   7 driven by the UHCI controller and one USB 2.0 bus driven by the EHCI
   8 controller.  Devices must be attached to the correct controller
   9 manually.
  10
  11 The '-usb' switch will make qemu create the UHCI controller as part of
  12 the PIIX3 chipset.  The USB 1.1 bus will carry the name "usb.0".
  13
  14 You can use the standard -device switch to add a EHCI controller to
  15 your virtual machine.  It is strongly recommended to specify an ID for
  16 the controller so the USB 2.0 bus gets a individual name, for example
  17 '-device usb-ehci,id=ehci".  This will give you a USB 2.0 bus named
  18 "ehci.0".
  19
  20 I strongly recomment to also use -device to attach usb devices because
  21 you can specify the bus they should be attached to this way.  Here is
  22 a complete example:
  23
  24     qemu -M pc ${otheroptions}                           \
  25         -drive if=none,id=usbstick,file=/path/to/image   \
  26         -usb                                             \
  27         -device usb-ehci,id=ehci                         \
  28         -device usb-tablet,bus=usb.0                     \
  29         -device usb-storage,bus=ehci.0,drive=usbstick
  30
  31 This attaches a usb tablet to the UHCI adapter and a usb mass storage
  32 device to the EHCI adapter.
  33
  34 enjoy,
  35   Gerd
  36
  37 --
  38 Gerd Hoffmann <kraxel@redhat.com>