USB Power Saving

Linux has the ability to power off USB devices and to let USB devices request to wake them up again.

It is important to note many optical mice do not support power saving. Once they lose power they cannot detect motion and cannot power back on when motion is invoked. With this being stated, it is possible to use specific driver calls or the sysfs file to enable or disable auto-suspend for individual USB peripherals.

Kernel
Set autosuspend to 1 second:

Enforce for every device:

If to autosuspend a specific USB device with newer kernels install package and use  utility to select specific device.

If  has been set in the kernel config and want your A4Tech mouse to autosuspend after 45 minutes of idle state then add   as a value to the GRUB_CMDLINE_LINUX_DEFAULT variable inside the config file found in. Regenerate the config via the  command and reboot in order for the changes to reflected on the next system reboot.

Next add the following file into the local.d services:

As you see here bus number of the mouse is 3 and the device number of 2 is auto-increased by 1 there by kernel into 3 (its usual behavior). Do not forget to make the local.d file executable:

Read for more information on power management in Linux.