USB Topology

USB devices are attached to a host in a tree through some number of hub devices. The lsusb command can be used to see how devices are physically attached to a Linux system.

# lsusb -t
Bus#  4
'-Dev#   1 Vendor 0x0000 Product 0x0000
Bus#  3
'-Dev#   1 Vendor 0x0000 Product 0x0000
  |-Dev#   2 Vendor 0x046d Product 0xc501
  '-Dev#   3 Vendor 0x0781 Product 0x0002
Bus#  2
'-Dev#   1 Vendor 0x0000 Product 0x0000
  |-Dev#   2 Vendor 0x0451 Product 0x2036
  | |-Dev#   5 Vendor 0x04b8 Product 0x0005
  | '-Dev#   6 Vendor 0x04b8 Product 0x0602
  '-Dev#   3 Vendor 0x0451 Product 0x2046
    '-Dev#   4 Vendor 0x056a Product 0x0011
Bus#  1
'-Dev#   1 Vendor 0x0000 Product 0x0000

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