usb-braille: Better explain that one also has to create a chardev backend

Users have reported not to understand the documentation. This completes
it to give an explicit example how one is supposed to set up a virtual
braille USB device.

Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
This commit is contained in:
Samuel Thibault 2022-09-06 00:09:50 +02:00
parent 61fd710b8d
commit 3e01455edd
1 changed files with 14 additions and 2 deletions

View File

@ -178,8 +178,20 @@ option or the ``device_add`` monitor command. Available devices are:
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.
Braille device. This emulates a Baum Braille device USB port. id has to
specify a character device defined with ``-chardev …,id=id``. One will
normally use BrlAPI to display the braille output on a BRLTTY-supported
device with
.. parsed-literal::
|qemu_system| [...] -chardev braille,id=brl -device usb-braille,chardev=brl
or alternatively, use the following equivalent shortcut:
.. parsed-literal::
|qemu_system| [...] -usbdevice braille
``usb-net[,netdev=id]``
Network adapter that supports CDC ethernet and RNDIS protocols. id