This is quite useful – if your USB connector times out your device connected to the Ubuntu machine (from here) – determine the idea using either
lsusb
or
lspci
It’s pretty self-explanatory…
105 The user interface for dynamic PM 106 --------------------------------- 107 108 The user interface for controlling dynamic PM is located in the power/ 109 subdirectory of each USB device's sysfs directory, that is, in 110 /sys/bus/usb/devices/.../power/ where "..." is the device's ID. The 111 relevant attribute files are: wakeup, level, and autosuspend. 112 113 power/wakeup 114 115 This file is empty if the device does not support 116 remote wakeup. Otherwise the file contains either the 117 word "enabled" or the word "disabled", and you can 118 write those words to the file. The setting determines 119 whether or not remote wakeup will be enabled when the 120 device is next suspended. (If the setting is changed 121 while the device is suspended, the change won't take 122 effect until the following suspend.) 123 124 power/level 125 126 This file contains one of three words: "on", "auto", 127 or "suspend". You can write those words to the file 128 to change the device's setting. 129 130 "on" means that the device should be resumed and 131 autosuspend is not allowed. (Of course, system 132 suspends are still allowed.) 133 134 "auto" is the normal state in which the kernel is 135 allowed to autosuspend and autoresume the device. 136 137 "suspend" means that the device should remain 138 suspended, and autoresume is not allowed. (But remote 139 wakeup may still be allowed, since it is controlled 140 separately by the power/wakeup attribute.) 141 142 power/autosuspend 143 144 This file contains an integer value, which is the 145 number of seconds the device should remain idle before 146 the kernel will autosuspend it (the idle-delay time). 147 The default is 2. 0 means to autosuspend as soon as 148 the device becomes idle, and -1 means never to 149 autosuspend. You can write a number to the file to 150 change the autosuspend idle-delay time. 151 152 Writing "-1" to power/autosuspend and writing "on" to power/level do 153 essentially the same thing -- they both prevent the device from being 154 autosuspended. Yes, this is a redundancy in the API.