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USB is short for Universial Serial BUS. There are currently five variants of USB. The new USB stack in FreeBSD -current supports Low-, Full-, High- and Super- speed USB devices in Host- and Device Mode.

  • Low Speed USB
  • Full Speed USB
  • High Speed USB
  • Super Speed USB
  • Wireless USB (not supported yet)
  • Q: I see the following error and USB stops working “Page offset was not preserved!”
  • A: Update your sources, this issue is fixed.
  • Q: I can't boot my Freesbie using USB2.
  • A: Update your sources, this issue is fixed.
  • Q: Screen updates in X11 are slow/broken/laggy
  • A: Ensure your kernel/world is up to date, old libs removed and the libpciaccess port is rebuilt.
  • Q: My mass storage device is not working, what can I do?
  • A: If your mass storage device needs a quirk, because it does not conform to the SCSI specification you can add it in the following way:
# 1) Unload "umass" if it is loaded.
# 2) Plug your device.
# 3) You might have to add a new entry for your device in /sys/dev/usb/usbdevs .
# 4) To get the VID+PID for your device you run "usbconfig -u X -a Y dump_device_desc"
# where X and Y are the numbers reported by ugen.
# For example:
usbconfig -u 4 -a 7 dump_device_desc

# 5) Try adding an entry in the quirktable in /sys/dev/usb/quirk/usb_quirk.c . 
# Look at the other quirks for examples.
  • usb.1558469328.txt.gz
  • Last modified: 2019/05/21 20:08
  • by AndrewFengler