Difference between revisions of "USB Device Diagnostics in Linux"

Revision as of 19:37, 28 February 2019

To detect your USB device, in a terminal, you can try:

lsusb
lsusb -v

The second, verbose, offering more detail.

Device are mainly identified using a pair of hexadecimal numbers, like 04b3:3108

The 4 first hexadecimal digits are the Vendor ID (04b3 = IBM).

The 4 last hexadecimal digits are the Device ID (3108 = ThinkPad 800dpi Optical Travel Mouse).

When your device is listed as "unknown" you can update your local usb-id definition by running update-usbids as root.

Try this:

lsusb -v | grep -E '\<(Bus|iProduct|bDeviceClass|bDeviceProtocol)' 2>/dev/null

Another way is to dump the information from the running kernel

sudo cat /sys/kernel/debug/usb/devices

Parse it a little

sudo cat /sys/kernel/debug/usb/devices | grep -E "^([TSPD]:.*|)$"

USB Input Devices

Input devices include keyboards, mice, remotes, etc.

They do not include flash drives.

summary

Another tool that provides extensive details for USB diagnostics:

sudo lsinput

You may have to install it first, it is part of input-utils

sudo apt install input-utils

A tool to show the device being recognized when inserted is

udevadm monitor --udev

The udevadm command cannot be run by itself. You must include a parameter to tell it what to do.

input-utils package

input-utils: utilities for the input layer of the Linux kernel: This is a collection of utilities which are useful when working with the input layer of the Linux kernel (version 2.6 and later). Included are utilities to list the input devices known to the kernel, show the input events that are received by a device, and query or modify keyboard maps. Specifically the tools deal with /dev/input/event* input devices.

• lsinput - dumps out all the input devices and the associated details
• input-kbd - dump out the keyboard mapping of a particular event device, must specify the device number such as 'sudo input-kbd 3'
• input-events - observe input events for watching a specific input device, must specify the device number such as 'sudo input-events 3'

udevadm

udevadm can be used to monitor USB connections

udevadm -h
Usage: udevadm [--help] [--version] [--debug] COMMAND [COMMAND OPTIONS]
  info         query sysfs or the udev database
  trigger      request events from the kernel
  settle       wait for the event queue to finish
  control      control the udev daemon
  monitor      listen to kernel and udev events
  hwdb         maintain the hardware database index
  test         test an event run
  test-builtin test a built-in command

To monitor USB connections here are some command usage examples:

udevadm monitor --subsystem-match=usb --property
udevadm monitor --subsystem-match=usb --property --udev

discover package

use the command discover

discover

a working example

I have connected a tiny USB receiver for an unknown pointing device. The manufacturer is unknown. I'm not sure if it is the correct dongle and if the device works. Here is where I start:

udevadm monitor --udev

Now that it is running, I will insert the USB receiver.

A lot of information showed up. Too many lines to share here. Whats important is this one:

UDEV  [42556.827151] add      /devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.7/2-1.7:1.0/0003:26E3:106C.0015 (hid)

I can find the device identification which is: 0003:26E3:106C.0015 and that it is a human interface device (hid) which includes the category of mouse and keyboard