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Usually the USB devices will get back to work after the power is resumed. However,
sometime the USB hub may need a reset to make sure all connected USB devices
will work properly.
You can follow
this tutorial
to compile a very small program to reset the USB hub. By
resetting the BIG7 USB hub, all USB devices that connected to the USB hub will be
reset as well.
In order to get the device ID for the BIG7 USB hub, you can run “lsusb –t” command:
The result above shows that BIG7 USB hub is device 4 and it is connected to port 3 in
USB bus 01. You may see different result though.
pi@raspberrypi:~ $ lsusb -t
/: Bus 01.Port 1: Dev 1, Class=root_hub, Driver=dwc_otg/1p, 480M
|__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/5p, 480M
|__ Port 1: Dev 3, If 0, Class=Vendor Specific Class, Driver=smsc95xx, 480M
|__ Port 3: Dev 4, If 0, Class=Hub, Driver=hub/7p, 480M
