root@arm:~# lsusb
Bus 001 Device 002: ID 1a40:0101 Terminus Technology Inc. 4-Port HUB
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

/etc/var/messages
...
[    3.103987] usb 1-1.3: new high-speed USB device number 3 using musb-hdrc
[    3.125876] udevd[97]: starting version 175
[    8.113626] usb 1-1.3: khubd timed out on ep0in len=18/64
[   13.193657] usb 1-1.3: khubd timed out on ep0in len=18/18
[   13.193678] usb 1-1.3: device descriptor read/all, error -110
[   13.265917] usb 1-1.3: new high-speed USB device number 4 using musb-hdrc
[   18.271795] usb 1-1.3: khubd timed out on ep0in len=18/64
[   23.351855] usb 1-1.3: khubd timed out on ep0in len=18/18
[   23.351875] usb 1-1.3: device descriptor read/all, error -110
[   23.424116] usb 1-1.3: new high-speed USB device number 5 using musb-hdrc
[   28.443657] usb 1-1.3: khubd timed out on ep0in len=8/8
[   28.443679] usb 1-1.3: device descriptor read/8, error -110
[   33.566702] usb 1-1.3: khubd timed out on ep0in len=8/8
[   33.566724] usb 1-1.3: device descriptor read/8, error -110
[   33.742474] usb 1-1.3: new high-speed USB device number 6 using musb-hdrc
[   38.762020] usb 1-1.3: khubd timed out on ep0in len=8/8
[   38.762041] usb 1-1.3: device descriptor read/8, error -110
[   43.885060] usb 1-1.3: khubd timed out on ep0in len=8/8
[   43.885081] usb 1-1.3: device descriptor read/8, error -110
[   43.994462] hub 1-1:1.0: unable to enumerate USB device on port 3
[   44.000922] hub 1-1:1.0: state 7 ports 4 chg 0000 evt 0008
[   44.006681] hub 1-1:1.0: hub_suspend
...
[ 1997.519833] musb_stage0_irq 496: bogus host RESUME (b_idle) ( when removing the Webcam from the hub )