Wake Your Computer by USB

I recently began using my laptop at my desk with a USB keyboard and mouse, and I thought I would explain how to set up Ubuntu so that USB peripherals will wake up your computer from sleep mode. This is convenient if you have your laptop set up such that the lid is closed and inaccessible.

In Ubuntu, the way to set this up is to edit the file located at /proc/acpi/wakeup. To see the current contents of this file do this:

% cat /proc/acpi/wakeup
Device  S-state   Status   Sysfs node
P0P2      S4     disabled  
P0P1      S4     disabled  pci:0000:00:1e.0
MC97      S4     disabled  
HDAC      S4     disabled  pci:0000:00:1b.0
P0P4      S4     disabled  pci:0000:00:1c.0
P0P5      S4     disabled  pci:0000:00:1c.1
P0P7      S4     disabled  
P0P8      S4     disabled  
P0P9      S4     disabled  
USB0      S3     disabled  pci:0000:00:1d.0
USB1      S3     disabled  pci:0000:00:1d.1
USB2      S3     disabled  pci:0000:00:1d.2
USB3      S3     disabled  pci:0000:00:1d.3
EUSB      S3     disabled  pci:0000:00:1d.7
P0P6      S4     disabled  pci:0000:00:1c.2
SLPB      S4    *enabled

This shows you a number of devices, most of which I don’t claim to understand. The ones to notice are the USB ones, which you will see are disabled by default.

Once these are toggled on, your computer will wake up from sleep when USB peripherals are used. To toggle one of these on, as root, run:

echo "USB0" > /proc/acpi/wakeup

This will toggle USB0 from disabled to enabled. To check this, run cat /proc/acpi/wakeup again. You should see that it’s enabled, and you should be able to test this by suspending your computer.

This will set up your computer to wake up from USB…for now. To make it work after your computer has been restarted, you will need to write a short init script named wake.sh with the following contents:

#!/bin/bash
echo "USB0" > /proc/acpi/wakeup

Save this file to /etc/init.d, and make it executable by running:

chmod +x wake.sh

Finally, once this file is in /etc/init.d, and is executable, as root run:

update-rc.d wake.sh defaults

That will make init know about the file, and run it at startup. Happy awakenings!

Source: http://ubuntuforums.org/showthread.php?t=711747