I have fingerprint-gui working in Ubuntu 16.04 on my Lenovo x260. The problem is that powertop indicates that it is constantly using about 50-100mW of power even when I am logged in and it should be off. Has anyone found a way to put the fingerprint reader to sleep when it is not being used?

The device in my machine is the following:

ID 138a:0017 Validity Sensors, Inc. Fingerprint Reader
  • 100mW is basically nothing – You'reAGitForNotUsingGit Apr 3 '17 at 17:47
  • Similar problem here with same device with ID 138a:0018. powertop is reporting, that it's using up to 4W (which is a 3rd of the laptop's idle consumption), while I don't even have the driver for the device installed anymore. $ cat /sys/bus/usb/devices/1-1.2/product -> "HP TrueVision HD". $ echo suspend | sudo tee /sys/bus/usb/drivers/usb/1-1.2/power/level` -> "tee: /sys/bus/usb/drivers/usb/1-1.2/power/level: invalid argument". Unbinding the device (which AFAIU should power it off): echo '1-1.2' | sudo tee /sys/bus/usb/drivers/usb/unbind works, but powertop is still showing it using pwr – Tomáš Pospíšek Feb 18 at 14:05
  • Similar question: unix.stackexchange.com/questions/314773/… – Tomáš Pospíšek Feb 18 at 14:07

strangely enough this seems to have fixed it for me:

echo on > /sys/bus/usb/devices/1-1.2/power/control

replace above with the correct USB device ID as necessary. You should be able to find the correct ID like this:

for p in /sys/bus/usb/devices/*/product; do echo -n "$p : "; cat $p; done
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