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i have heard that everything in linux is treated as files.. i was just curious as to where would i find to explore the usb mounted on my machine (HCI dev)

juggernauthk108
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2 Answers2

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You can get a list of USB devices connected to your machine via the command:

lsusb

You can monitor input events from USB and other devices via:

evtest

which will also tell you the device path (e.g. mouse and keyboard, as well as power button, etc.) in /dev/input/event*. You might need to install the evtest package for that.

This is a script (taken from this answer on Unix SE) which searches /sys looking for USB devices (i.e. the ones with a ID_SERIAL attribute):

#!/bin/bash

for sysdevpath in $(find /sys/bus/usb/devices/usb/ -name dev); do
    (
        syspath="${sysdevpath%/dev}"
        devname="$(udevadm info -q name -p $syspath)"
        [[ "$devname" == "bus/" ]] && exit
        eval "$(udevadm info -q property --export -p $syspath)"
        [[ -z "$ID_SERIAL" ]] && exit
        echo "/dev/$devname - $ID_SERIAL"
    )
done
Pablo Bianchi
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dr_
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  • i ran the evtest commmand... i chose for the touchpad event... i saw that the output also gives me value of pressure i apply on touchpad... can u pls share the code ,running which i get a pop up (sort of toast ) if i press the touch pad hard – juggernauthk108 Jan 24 '16 at 17:46
  • moreover when i cd /dev/input/ i see something called as "mice" "mouse1" "mouse0" and "mouse2" other than the directory by-id and by-path and the 13 events that evtest command would anyways display... how can make use of these "mice" "mouse1" "mouse0" and "mouse2"? – juggernauthk108 Jan 24 '16 at 17:50
2

I assume that you connect usb devices. When you type: 

lsusb

you have list connected usb devices. You can read bus and device number. Then when you type: 

lsusb -t

( bus and device number are known from lsusb ) you can read port number of device you are checking. e.g my mouse is on bus 001, device 004 and this belongs to port 14.

Now when you go to: 

/sys/bus/usb/drivers/usb

you can see there is e.g symlink 1-14 which is responsible for my mouse (bus 1, port 14). You can use realpath 1-14 command to see where this symlink leads
(You can disable this port by typing: echo '1-14' | sudo tee unbind )

EdiD
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