dmesg | grep usb
а в
[ 8858.071926] usb 2-4: new high-speed USB device number 5 using ehci-pci
[ 8858.233836] usb 2-4: New USB device found, idVendor=04a9, idProduct=319a
[ 8858.233841] usb 2-4: New USB device strings: Mfr=1, Product=2, SerialNumber=0
[ 8858.233843] usb 2-4: Product: Canon Digital Camera
[ 8858.233846] usb 2-4: Manufacturer: Canon Inc.
[ 8918.667889] usb 2-4: USB disconnect, device number 5
что означает usb 2-4: USB disconnect, device number 5