When I suspend the laptop, the USB devices are left on. I don't mind this in general, however I'd like to be able to turn off the cooling pad under it. I tried the things outlined in the following:
however this doesn't work anymore in Linux 3.0.0. I read the kernel docs:
and tried this (also outlined here - http://www.thinkwiki.org/wiki/How_to_reduce_power_consumption):
for i in /sys/bus/usb/devices/*/power/autosuspend; do echo 1|sudo tee $i; done for i in /sys/bus/usb/devices/*/power/level; do echo auto|sudo tee $i; done
I can confirm this works properly for some devices - e.g. my USB keyboard auto-suspends as expected. However, some devices do not - e.g. my USB touchpad, USB hub it's connected to and the cooler are left with power.
- Why are devices behaving differently? Does this mean that it's up to each of the devices to decide whether to suspend?
- Is there a way to determine whether a device will go into suspend mode?
- Finally, is there a way to force a device to power down?