Controlling a USB power supply (on/off) with linux

up vote
142
down vote

favorite

Is it possible to turn on/off power supplies from USB manually with linux?

There's this external USB cooling fan (the kind you use to cool yourself off, not the PC), and it would be nice to be able to control it from the terminal, because I want to position the fan somewhere far away.

I suppose this could also be useful for a variety of other things as well, because there's a lot of USB toys out there. Maybe air purifiers etc (I heard they don't really work though).

asked Jan 15 '11 at 21:19

kamziro

2,90174267

7

Let me recap for Linux >= 2.6.38: The file power/level is deprecated now; use power/control instead. (power/wakeup is ok.) Furthermore, it accepts only "auto" and "on", not "suspend" any more. "auto" is smart enough, and if the power isn't turned off while idle, it's the device's fault. Anyway you can't turn the power off manually. For more, see the answer below by tlwhitec and the kernel's doc: kernel.org/doc/Documentation/usb/power-management.txt
– teika kazura
Jul 4 '13 at 6:51

Possible duplicate of stackoverflow.com/q/1163824/1967396
– Floris
Apr 13 '14 at 4:32

2

This feature really deserves a good GUI
– mikebabcock
Dec 5 '14 at 5:28

Does it require any special hardware? It is not quite clear from answers,
– Vojtěch Dohnal
Jun 14 '16 at 4:47

add a comment |

up vote
142
down vote

favorite

Is it possible to turn on/off power supplies from USB manually with linux?

I suppose this could also be useful for a variety of other things as well, because there's a lot of USB toys out there. Maybe air purifiers etc (I heard they don't really work though).

asked Jan 15 '11 at 21:19

kamziro

2,90174267

7

Let me recap for Linux >= 2.6.38: The file power/level is deprecated now; use power/control instead. (power/wakeup is ok.) Furthermore, it accepts only "auto" and "on", not "suspend" any more. "auto" is smart enough, and if the power isn't turned off while idle, it's the device's fault. Anyway you can't turn the power off manually. For more, see the answer below by tlwhitec and the kernel's doc: kernel.org/doc/Documentation/usb/power-management.txt
– teika kazura
Jul 4 '13 at 6:51

Possible duplicate of stackoverflow.com/q/1163824/1967396
– Floris
Apr 13 '14 at 4:32

2

This feature really deserves a good GUI
– mikebabcock
Dec 5 '14 at 5:28

Does it require any special hardware? It is not quite clear from answers,
– Vojtěch Dohnal
Jun 14 '16 at 4:47

add a comment |

up vote
142
down vote

favorite

Is it possible to turn on/off power supplies from USB manually with linux?

I suppose this could also be useful for a variety of other things as well, because there's a lot of USB toys out there. Maybe air purifiers etc (I heard they don't really work though).

asked Jan 15 '11 at 21:19

kamziro

2,90174267

Is it possible to turn on/off power supplies from USB manually with linux?

I suppose this could also be useful for a variety of other things as well, because there's a lot of USB toys out there. Maybe air purifiers etc (I heard they don't really work though).

linux usb

asked Jan 15 '11 at 21:19

kamziro

2,90174267

asked Jan 15 '11 at 21:19

kamziro

2,90174267

asked Jan 15 '11 at 21:19

kamziro

2,90174267

asked Jan 15 '11 at 21:19

kamziro

2,90174267

asked Jan 15 '11 at 21:19

kamziro

2,90174267

7

Let me recap for Linux >= 2.6.38: The file power/level is deprecated now; use power/control instead. (power/wakeup is ok.) Furthermore, it accepts only "auto" and "on", not "suspend" any more. "auto" is smart enough, and if the power isn't turned off while idle, it's the device's fault. Anyway you can't turn the power off manually. For more, see the answer below by tlwhitec and the kernel's doc: kernel.org/doc/Documentation/usb/power-management.txt
– teika kazura
Jul 4 '13 at 6:51

Possible duplicate of stackoverflow.com/q/1163824/1967396
– Floris
Apr 13 '14 at 4:32

2

This feature really deserves a good GUI
– mikebabcock
Dec 5 '14 at 5:28

Does it require any special hardware? It is not quite clear from answers,
– Vojtěch Dohnal
Jun 14 '16 at 4:47

add a comment |

7

Let me recap for Linux >= 2.6.38: The file power/level is deprecated now; use power/control instead. (power/wakeup is ok.) Furthermore, it accepts only "auto" and "on", not "suspend" any more. "auto" is smart enough, and if the power isn't turned off while idle, it's the device's fault. Anyway you can't turn the power off manually. For more, see the answer below by tlwhitec and the kernel's doc: kernel.org/doc/Documentation/usb/power-management.txt
– teika kazura
Jul 4 '13 at 6:51

Possible duplicate of stackoverflow.com/q/1163824/1967396
– Floris
Apr 13 '14 at 4:32

2

This feature really deserves a good GUI
– mikebabcock
Dec 5 '14 at 5:28

Does it require any special hardware? It is not quite clear from answers,
– Vojtěch Dohnal
Jun 14 '16 at 4:47

Let me recap for Linux >= 2.6.38: The file power/level is deprecated now; use power/control instead. (power/wakeup is ok.) Furthermore, it accepts only "auto" and "on", not "suspend" any more. "auto" is smart enough, and if the power isn't turned off while idle, it's the device's fault. Anyway you can't turn the power off manually. For more, see the answer below by tlwhitec and the kernel's doc: kernel.org/doc/Documentation/usb/power-management.txt
– teika kazura
Jul 4 '13 at 6:51

Possible duplicate of stackoverflow.com/q/1163824/1967396
– Floris
Apr 13 '14 at 4:32

This feature really deserves a good GUI
– mikebabcock
Dec 5 '14 at 5:28

Does it require any special hardware? It is not quite clear from answers,
– Vojtěch Dohnal
Jun 14 '16 at 4:47

add a comment |

9 Answers
9

active

oldest

votes

up vote
59
down vote

accepted

Note. The information in this answer is relevant for the older kernels (up to 2.6.32). See tlwhitec's answer for the information on the newer kernels.

# disable external wake-up; do this only once

echo disabled > /sys/bus/usb/devices/usb1/power/wakeup 



echo on > /sys/bus/usb/devices/usb1/power/level       # turn on

echo suspend > /sys/bus/usb/devices/usb1/power/level  # turn off

(You may need to change usb1 to usb n)

Source: Documentation/usb/power-management.txt.gz

edited Dec 6 '17 at 14:08

ItamarG3

3,43861938

answered Jan 15 '11 at 21:42

Roman Cheplyaka

28.1k456101

1

Whoa, thanks for that. I was thinking I had to go through libUSB no matter what. Any idea how to get the names of the attached devices as well?
– kamziro
Jan 15 '11 at 21:56

2

@kamziro: try lsusb
– Roman Cheplyaka
Jan 15 '11 at 23:53

7

Doesn't work in Linux Ubuntu 2.6.32-26-generic
– NoBugs
Dec 31 '11 at 20:48

5

I'm getting permission denied error even if I use sudo!
– Wally
Jul 26 '14 at 7:52

2

same for me " permission denied" even after using sudo
– Raulp
Mar 4 '15 at 12:03

|
show 8 more comments

up vote
53
down vote

According to the docs, there were several changes to the USB power management from kernels 2.6.32, which seem to settle in 2.6.38. Now you'll need to wait for the device to become idle, which is governed by the particular device driver. The driver needs to support it, otherwise the device will never reach this state. Unluckily, now the user has no chance to force this. However, if you're lucky and your device can become idle, then to turn this off you need to:

echo "0" > "/sys/bus/usb/devices/usbX/power/autosuspend"

echo "auto" > "/sys/bus/usb/devices/usbX/power/level"

or, for kernels around 2.6.38 and above:

echo "0" > "/sys/bus/usb/devices/usbX/power/autosuspend_delay_ms"

echo "auto" > "/sys/bus/usb/devices/usbX/power/control"

This literally means, go suspend at the moment the device becomes idle.

So unless your fan is something "intelligent" that can be seen as a device and controlled by a driver, you probably won't have much luck on current kernels.

answered Oct 1 '12 at 14:56

tlwhitec

886813

It seems this will cause the USB device to continuously get powered off...(?) How should power be resumed by me, after this worked? My goal is to restart the device once, not to permanently change its suspension configuration.
– matanster
Aug 16 '13 at 17:27

3

To resume a suspended device, you can disable again the "autosuspend" with echo "on" > "/sys/bus/usb/devices/usbX/power/control", but I think you need to understand the original purpose. The autosuspend feature is here merely to enable idling devices to enter a low-power state (where it might appear turned off), only to be resumed later when it's needed, either by the host or some external event. That happens (or should happen) automatically. The port itself is actually never truly turned off. Really, do read the docs ;)
– tlwhitec
Sep 24 '13 at 10:01

3

I can confirm it works with kernels > 3.10. Just have to be sure that the device "id" you are using is correct : dmesg | grep "usb" and use the number after "usb", for example: usb 2-4.4: SerialNumber: A0848020 you will use: /sys/bus/usb/devices/2-4.4/power/.... Also, be sure that the device is not in use. I created a script to simplify this process
– lepe
Apr 27 '16 at 3:07

add a comment |

up vote
21
down vote

I have found these solutions that at least work for properly configured Terminus FE 1.1 USB hub chip:

1.To turn off power on all USB ports of a hub, you may unbind the hub from kernel using:

echo "1-4.4.4" > /sys/bus/usb/drivers/usb/unbind

to turn power back on - you may bind it back using

echo "1-4.4.4" > /sys/bus/usb/drivers/usb/bind

2.Switching power at each port individually is trickier: I was able to use hubpower to control each port - but it comes with a downside: hubpower first disconnects the usbdevfs wich causes all of the USB devices to disconect from system, at least on ubuntu:

usb_ioctl.ioctl_code = USBDEVFS_DISCONNECT;

rc = ioctl(fd, USBDEVFS_IOCTL, &usb_ioctl);

With this ioctl disabled I was able to switch off individual port power without detaching all devices - but the power goes back on immediately (probably due to kernel seeing an uninitialized device) which causes USB device just to do a "cold restart" which is what I generally wanted to do. My patched hubpower is here

answered Aug 7 '13 at 8:12

grandrew

402410

The bind/unbind entries are confirmed to work on linux kernel 2.6.34, the ICH8 chipset, and Ubuntu 10.04.
– user1357196
Aug 22 '13 at 16:10

4

bind/unbind doesn't poweroff the USB port regardless the chipset. The device still gets power...
– themihai
Nov 8 '14 at 18:41

mouse laser is off, keyboard cant type, modem stops blinking - all good on my platform
– eri
Sep 19 '16 at 1:17

add a comment |

up vote
17
down vote

PowerTOP from Intel allows you to toggle devices such as usb peripherals in real-time. These are called 'tunables'.

sudo apt install powertop

sudo powertop

Tab over to 'tunables'.

Scroll down to your device.

Hit enter to toggle power saving mode (Good/Bad)

enter image description here

Note that Bad means the device is always on. Toggling to Good will turn off the device after the preset inactive saving time (default is 2000ms).

See the PowerTOP docs for details on how to make these changes permanent.
It generates the config scripts for you (pretty much as described by other posters on this thread).

NOTE: These scripts do not affect USB pin power (which is always on).

These only send the driver protocol to activate and deactivate a device.

If you want to control pin power, you could use either a supported smart USB hub, or better yet a microcontroller.

edited Jun 27 '17 at 22:41

answered May 6 '16 at 5:54

Dominic Cerisano

1,3811731

2

Awesome! :D I think this is the userfriendliest way to do it (although on low level it makes the same operations as outlined in the other answers.) Thank you, and may your answer reach the top ;)
– Matyas
May 9 '16 at 9:03

1

Thanks for your answer. Where do I have to start digging to change the preset inactive saving time?
– mikezter
Dec 21 '16 at 11:55

As mentioned by previous posters, kernel docs are here: kernel.org/doc/Documentation/usb/power-management.txt
– Dominic Cerisano
Mar 9 '17 at 21:17

add a comment |

up vote
7
down vote

I wanted to do this, and with my USB hardware I couldn't. I wrote a hacky way how to do it here: http://pintant.cat/2012/05/12/power-off-usb-device/ . In short way: I used a USB relay to open/close the Vc of another USB cable...

answered May 20 '12 at 10:25

Carles

10111

add a comment |

up vote
7
down vote

You could use uhubctl - command line utility to control USB power per port for compatible USB hubs.

Disclosure - I am the author of uhubctl.

edited May 20 at 3:58

answered Nov 8 '16 at 20:00

mvp

69.9k885122

fine tool on osx, but doesnt find any 'supported smart hub' on debian for me.
– jitter
Jan 7 at 23:13

1

On Linux, you need to either run it as root (under sudo), or to configure udev device permissions. It's also possible that your Linux host doesn't have compatible hubs connected.
– mvp
Jan 7 at 23:15

it's a 'beagle bone green' btw.
– jitter
Jan 11 at 1:55

add a comment |

up vote
5
down vote

echo '2-1' |sudo tee /sys/bus/usb/drivers/usb/unbind

works for ubuntu

edited Apr 12 '14 at 17:05

mustaccio

14k83637

answered Apr 12 '14 at 16:46

user3527264

5111

YOURS IS THE ONLY SOLUTION THAT WORKED ON MY CASE. I am using an acer make laptop 12.04LTS Ubuntu.
– RicoRicochet
Dec 12 '14 at 5:57

Doesn't poweroff the device, only removes it from the device list. How can I poweroff the USB port?
– rustyx
Dec 20 '14 at 15:11

This is also the only solution that worked for me for powering off a Wacom Intuos5 touch M tablet without unplugging it (on Fedora 28)
– user1738984
Sep 11 at 10:50

add a comment |

up vote
2
down vote

USB 5v power is always on (even when the computer is turned off, on some computers and on some ports.) You will probably need to program an Arduino with some sort of switch, and control it via Serial library from USB plugged in to the computer.

In other words, a combination of this switch tutorial and this tutorial on communicating via Serial libary to Arduino plugged in via USB.

answered Nov 24 '16 at 2:55

NoBugs

5,346857111

add a comment |

up vote
0
down vote

I had a problem when connecting my android phone, I couldn't charge my phone because the power switch on and then off ...
PowerTop let me find this setting and was useful to fix the issue ( auto value was causing issue):

echo 'on' | sudo tee /sys/bus/usb/devices/1-1/power/control

answered Jul 17 '17 at 8:51

WonderLand

3,19733759

add a comment |

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9 Answers
9

active

oldest

votes

9 Answers
9

active

oldest

votes

up vote
59
down vote

accepted

Note. The information in this answer is relevant for the older kernels (up to 2.6.32). See tlwhitec's answer for the information on the newer kernels.

# disable external wake-up; do this only once

echo disabled > /sys/bus/usb/devices/usb1/power/wakeup 



echo on > /sys/bus/usb/devices/usb1/power/level       # turn on

echo suspend > /sys/bus/usb/devices/usb1/power/level  # turn off

(You may need to change usb1 to usb n)

Source: Documentation/usb/power-management.txt.gz

edited Dec 6 '17 at 14:08

ItamarG3

3,43861938

answered Jan 15 '11 at 21:42

Roman Cheplyaka

28.1k456101

1

Whoa, thanks for that. I was thinking I had to go through libUSB no matter what. Any idea how to get the names of the attached devices as well?
– kamziro
Jan 15 '11 at 21:56

2

@kamziro: try lsusb
– Roman Cheplyaka
Jan 15 '11 at 23:53

7

Doesn't work in Linux Ubuntu 2.6.32-26-generic
– NoBugs
Dec 31 '11 at 20:48

5

I'm getting permission denied error even if I use sudo!
– Wally
Jul 26 '14 at 7:52

2

same for me " permission denied" even after using sudo
– Raulp
Mar 4 '15 at 12:03

|
show 8 more comments

up vote
59
down vote

accepted

Note. The information in this answer is relevant for the older kernels (up to 2.6.32). See tlwhitec's answer for the information on the newer kernels.

# disable external wake-up; do this only once

echo disabled > /sys/bus/usb/devices/usb1/power/wakeup 



echo on > /sys/bus/usb/devices/usb1/power/level       # turn on

echo suspend > /sys/bus/usb/devices/usb1/power/level  # turn off

(You may need to change usb1 to usb n)

Source: Documentation/usb/power-management.txt.gz

edited Dec 6 '17 at 14:08

ItamarG3

3,43861938

answered Jan 15 '11 at 21:42

Roman Cheplyaka

28.1k456101

1

Whoa, thanks for that. I was thinking I had to go through libUSB no matter what. Any idea how to get the names of the attached devices as well?
– kamziro
Jan 15 '11 at 21:56

2

@kamziro: try lsusb
– Roman Cheplyaka
Jan 15 '11 at 23:53

7

Doesn't work in Linux Ubuntu 2.6.32-26-generic
– NoBugs
Dec 31 '11 at 20:48

5

I'm getting permission denied error even if I use sudo!
– Wally
Jul 26 '14 at 7:52

2

same for me " permission denied" even after using sudo
– Raulp
Mar 4 '15 at 12:03

|
show 8 more comments

up vote
59
down vote

accepted

Note. The information in this answer is relevant for the older kernels (up to 2.6.32). See tlwhitec's answer for the information on the newer kernels.

# disable external wake-up; do this only once

echo disabled > /sys/bus/usb/devices/usb1/power/wakeup 



echo on > /sys/bus/usb/devices/usb1/power/level       # turn on

echo suspend > /sys/bus/usb/devices/usb1/power/level  # turn off

(You may need to change usb1 to usb n)

Source: Documentation/usb/power-management.txt.gz

edited Dec 6 '17 at 14:08

ItamarG3

3,43861938

answered Jan 15 '11 at 21:42

Roman Cheplyaka

28.1k456101

Note. The information in this answer is relevant for the older kernels (up to 2.6.32). See tlwhitec's answer for the information on the newer kernels.

# disable external wake-up; do this only once

echo disabled > /sys/bus/usb/devices/usb1/power/wakeup 



echo on > /sys/bus/usb/devices/usb1/power/level       # turn on

echo suspend > /sys/bus/usb/devices/usb1/power/level  # turn off

(You may need to change usb1 to usb n)

Source: Documentation/usb/power-management.txt.gz

edited Dec 6 '17 at 14:08

ItamarG3

3,43861938

answered Jan 15 '11 at 21:42

Roman Cheplyaka

28.1k456101

edited Dec 6 '17 at 14:08

ItamarG3

3,43861938

edited Dec 6 '17 at 14:08

ItamarG3

3,43861938

edited Dec 6 '17 at 14:08

ItamarG3

3,43861938

answered Jan 15 '11 at 21:42

Roman Cheplyaka

28.1k456101

answered Jan 15 '11 at 21:42

Roman Cheplyaka

28.1k456101

answered Jan 15 '11 at 21:42

Roman Cheplyaka

28.1k456101

1

Whoa, thanks for that. I was thinking I had to go through libUSB no matter what. Any idea how to get the names of the attached devices as well?
– kamziro
Jan 15 '11 at 21:56

2

@kamziro: try lsusb
– Roman Cheplyaka
Jan 15 '11 at 23:53

7

Doesn't work in Linux Ubuntu 2.6.32-26-generic
– NoBugs
Dec 31 '11 at 20:48

5

I'm getting permission denied error even if I use sudo!
– Wally
Jul 26 '14 at 7:52

2

same for me " permission denied" even after using sudo
– Raulp
Mar 4 '15 at 12:03

|
show 8 more comments

1

Whoa, thanks for that. I was thinking I had to go through libUSB no matter what. Any idea how to get the names of the attached devices as well?
– kamziro
Jan 15 '11 at 21:56

2

@kamziro: try lsusb
– Roman Cheplyaka
Jan 15 '11 at 23:53

7

Doesn't work in Linux Ubuntu 2.6.32-26-generic
– NoBugs
Dec 31 '11 at 20:48

5

I'm getting permission denied error even if I use sudo!
– Wally
Jul 26 '14 at 7:52

2

same for me " permission denied" even after using sudo
– Raulp
Mar 4 '15 at 12:03

Whoa, thanks for that. I was thinking I had to go through libUSB no matter what. Any idea how to get the names of the attached devices as well?
– kamziro
Jan 15 '11 at 21:56

@kamziro: try lsusb
– Roman Cheplyaka
Jan 15 '11 at 23:53

Doesn't work in Linux Ubuntu 2.6.32-26-generic
– NoBugs
Dec 31 '11 at 20:48

I'm getting permission denied error even if I use sudo!
– Wally
Jul 26 '14 at 7:52

same for me " permission denied" even after using sudo
– Raulp
Mar 4 '15 at 12:03

|
show 8 more comments

up vote
53
down vote

echo "0" > "/sys/bus/usb/devices/usbX/power/autosuspend"

echo "auto" > "/sys/bus/usb/devices/usbX/power/level"

or, for kernels around 2.6.38 and above:

echo "0" > "/sys/bus/usb/devices/usbX/power/autosuspend_delay_ms"

echo "auto" > "/sys/bus/usb/devices/usbX/power/control"

This literally means, go suspend at the moment the device becomes idle.

So unless your fan is something "intelligent" that can be seen as a device and controlled by a driver, you probably won't have much luck on current kernels.

answered Oct 1 '12 at 14:56

tlwhitec

886813

It seems this will cause the USB device to continuously get powered off...(?) How should power be resumed by me, after this worked? My goal is to restart the device once, not to permanently change its suspension configuration.
– matanster
Aug 16 '13 at 17:27

3

To resume a suspended device, you can disable again the "autosuspend" with echo "on" > "/sys/bus/usb/devices/usbX/power/control", but I think you need to understand the original purpose. The autosuspend feature is here merely to enable idling devices to enter a low-power state (where it might appear turned off), only to be resumed later when it's needed, either by the host or some external event. That happens (or should happen) automatically. The port itself is actually never truly turned off. Really, do read the docs ;)
– tlwhitec
Sep 24 '13 at 10:01

3

I can confirm it works with kernels > 3.10. Just have to be sure that the device "id" you are using is correct : dmesg | grep "usb" and use the number after "usb", for example: usb 2-4.4: SerialNumber: A0848020 you will use: /sys/bus/usb/devices/2-4.4/power/.... Also, be sure that the device is not in use. I created a script to simplify this process
– lepe
Apr 27 '16 at 3:07

add a comment |

up vote
53
down vote

echo "0" > "/sys/bus/usb/devices/usbX/power/autosuspend"

echo "auto" > "/sys/bus/usb/devices/usbX/power/level"

or, for kernels around 2.6.38 and above:

echo "0" > "/sys/bus/usb/devices/usbX/power/autosuspend_delay_ms"

echo "auto" > "/sys/bus/usb/devices/usbX/power/control"

This literally means, go suspend at the moment the device becomes idle.

So unless your fan is something "intelligent" that can be seen as a device and controlled by a driver, you probably won't have much luck on current kernels.

answered Oct 1 '12 at 14:56

tlwhitec

886813

It seems this will cause the USB device to continuously get powered off...(?) How should power be resumed by me, after this worked? My goal is to restart the device once, not to permanently change its suspension configuration.
– matanster
Aug 16 '13 at 17:27

3

To resume a suspended device, you can disable again the "autosuspend" with echo "on" > "/sys/bus/usb/devices/usbX/power/control", but I think you need to understand the original purpose. The autosuspend feature is here merely to enable idling devices to enter a low-power state (where it might appear turned off), only to be resumed later when it's needed, either by the host or some external event. That happens (or should happen) automatically. The port itself is actually never truly turned off. Really, do read the docs ;)
– tlwhitec
Sep 24 '13 at 10:01

3

I can confirm it works with kernels > 3.10. Just have to be sure that the device "id" you are using is correct : dmesg | grep "usb" and use the number after "usb", for example: usb 2-4.4: SerialNumber: A0848020 you will use: /sys/bus/usb/devices/2-4.4/power/.... Also, be sure that the device is not in use. I created a script to simplify this process
– lepe
Apr 27 '16 at 3:07

add a comment |

up vote
53
down vote

echo "0" > "/sys/bus/usb/devices/usbX/power/autosuspend"

echo "auto" > "/sys/bus/usb/devices/usbX/power/level"

or, for kernels around 2.6.38 and above:

echo "0" > "/sys/bus/usb/devices/usbX/power/autosuspend_delay_ms"

echo "auto" > "/sys/bus/usb/devices/usbX/power/control"

This literally means, go suspend at the moment the device becomes idle.

So unless your fan is something "intelligent" that can be seen as a device and controlled by a driver, you probably won't have much luck on current kernels.

answered Oct 1 '12 at 14:56

tlwhitec

886813

echo "0" > "/sys/bus/usb/devices/usbX/power/autosuspend"

echo "auto" > "/sys/bus/usb/devices/usbX/power/level"

or, for kernels around 2.6.38 and above:

echo "0" > "/sys/bus/usb/devices/usbX/power/autosuspend_delay_ms"

echo "auto" > "/sys/bus/usb/devices/usbX/power/control"

This literally means, go suspend at the moment the device becomes idle.

So unless your fan is something "intelligent" that can be seen as a device and controlled by a driver, you probably won't have much luck on current kernels.

answered Oct 1 '12 at 14:56

tlwhitec

886813

answered Oct 1 '12 at 14:56

tlwhitec

886813

answered Oct 1 '12 at 14:56

tlwhitec

886813

answered Oct 1 '12 at 14:56

tlwhitec

886813

It seems this will cause the USB device to continuously get powered off...(?) How should power be resumed by me, after this worked? My goal is to restart the device once, not to permanently change its suspension configuration.
– matanster
Aug 16 '13 at 17:27

3

To resume a suspended device, you can disable again the "autosuspend" with echo "on" > "/sys/bus/usb/devices/usbX/power/control", but I think you need to understand the original purpose. The autosuspend feature is here merely to enable idling devices to enter a low-power state (where it might appear turned off), only to be resumed later when it's needed, either by the host or some external event. That happens (or should happen) automatically. The port itself is actually never truly turned off. Really, do read the docs ;)
– tlwhitec
Sep 24 '13 at 10:01

3

I can confirm it works with kernels > 3.10. Just have to be sure that the device "id" you are using is correct : dmesg | grep "usb" and use the number after "usb", for example: usb 2-4.4: SerialNumber: A0848020 you will use: /sys/bus/usb/devices/2-4.4/power/.... Also, be sure that the device is not in use. I created a script to simplify this process
– lepe
Apr 27 '16 at 3:07

add a comment |

It seems this will cause the USB device to continuously get powered off...(?) How should power be resumed by me, after this worked? My goal is to restart the device once, not to permanently change its suspension configuration.
– matanster
Aug 16 '13 at 17:27

3

To resume a suspended device, you can disable again the "autosuspend" with echo "on" > "/sys/bus/usb/devices/usbX/power/control", but I think you need to understand the original purpose. The autosuspend feature is here merely to enable idling devices to enter a low-power state (where it might appear turned off), only to be resumed later when it's needed, either by the host or some external event. That happens (or should happen) automatically. The port itself is actually never truly turned off. Really, do read the docs ;)
– tlwhitec
Sep 24 '13 at 10:01

3

I can confirm it works with kernels > 3.10. Just have to be sure that the device "id" you are using is correct : dmesg | grep "usb" and use the number after "usb", for example: usb 2-4.4: SerialNumber: A0848020 you will use: /sys/bus/usb/devices/2-4.4/power/.... Also, be sure that the device is not in use. I created a script to simplify this process
– lepe
Apr 27 '16 at 3:07

It seems this will cause the USB device to continuously get powered off...(?) How should power be resumed by me, after this worked? My goal is to restart the device once, not to permanently change its suspension configuration.
– matanster
Aug 16 '13 at 17:27

To resume a suspended device, you can disable again the "autosuspend" with echo "on" > "/sys/bus/usb/devices/usbX/power/control", but I think you need to understand the original purpose. The autosuspend feature is here merely to enable idling devices to enter a low-power state (where it might appear turned off), only to be resumed later when it's needed, either by the host or some external event. That happens (or should happen) automatically. The port itself is actually never truly turned off. Really, do read the docs ;)
– tlwhitec
Sep 24 '13 at 10:01

I can confirm it works with kernels > 3.10. Just have to be sure that the device "id" you are using is correct : dmesg | grep "usb" and use the number after "usb", for example: usb 2-4.4: SerialNumber: A0848020 you will use: /sys/bus/usb/devices/2-4.4/power/.... Also, be sure that the device is not in use. I created a script to simplify this process
– lepe
Apr 27 '16 at 3:07

add a comment |

up vote
21
down vote

I have found these solutions that at least work for properly configured Terminus FE 1.1 USB hub chip:

1.To turn off power on all USB ports of a hub, you may unbind the hub from kernel using:

echo "1-4.4.4" > /sys/bus/usb/drivers/usb/unbind

to turn power back on - you may bind it back using

echo "1-4.4.4" > /sys/bus/usb/drivers/usb/bind

usb_ioctl.ioctl_code = USBDEVFS_DISCONNECT;

rc = ioctl(fd, USBDEVFS_IOCTL, &usb_ioctl);

answered Aug 7 '13 at 8:12

grandrew

402410

The bind/unbind entries are confirmed to work on linux kernel 2.6.34, the ICH8 chipset, and Ubuntu 10.04.
– user1357196
Aug 22 '13 at 16:10

4

bind/unbind doesn't poweroff the USB port regardless the chipset. The device still gets power...
– themihai
Nov 8 '14 at 18:41

mouse laser is off, keyboard cant type, modem stops blinking - all good on my platform
– eri
Sep 19 '16 at 1:17

add a comment |

up vote
21
down vote

I have found these solutions that at least work for properly configured Terminus FE 1.1 USB hub chip:

1.To turn off power on all USB ports of a hub, you may unbind the hub from kernel using:

echo "1-4.4.4" > /sys/bus/usb/drivers/usb/unbind

to turn power back on - you may bind it back using

echo "1-4.4.4" > /sys/bus/usb/drivers/usb/bind

usb_ioctl.ioctl_code = USBDEVFS_DISCONNECT;

rc = ioctl(fd, USBDEVFS_IOCTL, &usb_ioctl);

answered Aug 7 '13 at 8:12

grandrew

402410

The bind/unbind entries are confirmed to work on linux kernel 2.6.34, the ICH8 chipset, and Ubuntu 10.04.
– user1357196
Aug 22 '13 at 16:10

4

bind/unbind doesn't poweroff the USB port regardless the chipset. The device still gets power...
– themihai
Nov 8 '14 at 18:41

mouse laser is off, keyboard cant type, modem stops blinking - all good on my platform
– eri
Sep 19 '16 at 1:17

add a comment |

up vote
21
down vote

I have found these solutions that at least work for properly configured Terminus FE 1.1 USB hub chip:

1.To turn off power on all USB ports of a hub, you may unbind the hub from kernel using:

echo "1-4.4.4" > /sys/bus/usb/drivers/usb/unbind

to turn power back on - you may bind it back using

echo "1-4.4.4" > /sys/bus/usb/drivers/usb/bind

usb_ioctl.ioctl_code = USBDEVFS_DISCONNECT;

rc = ioctl(fd, USBDEVFS_IOCTL, &usb_ioctl);

answered Aug 7 '13 at 8:12

grandrew

402410

I have found these solutions that at least work for properly configured Terminus FE 1.1 USB hub chip:

1.To turn off power on all USB ports of a hub, you may unbind the hub from kernel using:

echo "1-4.4.4" > /sys/bus/usb/drivers/usb/unbind

to turn power back on - you may bind it back using

echo "1-4.4.4" > /sys/bus/usb/drivers/usb/bind

usb_ioctl.ioctl_code = USBDEVFS_DISCONNECT;

rc = ioctl(fd, USBDEVFS_IOCTL, &usb_ioctl);

answered Aug 7 '13 at 8:12

grandrew

402410

answered Aug 7 '13 at 8:12

grandrew

402410

answered Aug 7 '13 at 8:12

grandrew

402410

answered Aug 7 '13 at 8:12

grandrew

402410

The bind/unbind entries are confirmed to work on linux kernel 2.6.34, the ICH8 chipset, and Ubuntu 10.04.
– user1357196
Aug 22 '13 at 16:10

4

bind/unbind doesn't poweroff the USB port regardless the chipset. The device still gets power...
– themihai
Nov 8 '14 at 18:41

mouse laser is off, keyboard cant type, modem stops blinking - all good on my platform
– eri
Sep 19 '16 at 1:17

add a comment |

The bind/unbind entries are confirmed to work on linux kernel 2.6.34, the ICH8 chipset, and Ubuntu 10.04.
– user1357196
Aug 22 '13 at 16:10

4

bind/unbind doesn't poweroff the USB port regardless the chipset. The device still gets power...
– themihai
Nov 8 '14 at 18:41

mouse laser is off, keyboard cant type, modem stops blinking - all good on my platform
– eri
Sep 19 '16 at 1:17

The bind/unbind entries are confirmed to work on linux kernel 2.6.34, the ICH8 chipset, and Ubuntu 10.04.
– user1357196
Aug 22 '13 at 16:10

bind/unbind doesn't poweroff the USB port regardless the chipset. The device still gets power...
– themihai
Nov 8 '14 at 18:41

mouse laser is off, keyboard cant type, modem stops blinking - all good on my platform
– eri
Sep 19 '16 at 1:17

add a comment |

up vote
17
down vote

PowerTOP from Intel allows you to toggle devices such as usb peripherals in real-time. These are called 'tunables'.

sudo apt install powertop

sudo powertop

Tab over to 'tunables'.

Scroll down to your device.

Hit enter to toggle power saving mode (Good/Bad)

enter image description here

Note that Bad means the device is always on. Toggling to Good will turn off the device after the preset inactive saving time (default is 2000ms).

See the PowerTOP docs for details on how to make these changes permanent.
It generates the config scripts for you (pretty much as described by other posters on this thread).

edited Jun 27 '17 at 22:41

answered May 6 '16 at 5:54

Dominic Cerisano

1,3811731

2

Awesome! :D I think this is the userfriendliest way to do it (although on low level it makes the same operations as outlined in the other answers.) Thank you, and may your answer reach the top ;)
– Matyas
May 9 '16 at 9:03

1

Thanks for your answer. Where do I have to start digging to change the preset inactive saving time?
– mikezter
Dec 21 '16 at 11:55

As mentioned by previous posters, kernel docs are here: kernel.org/doc/Documentation/usb/power-management.txt
– Dominic Cerisano
Mar 9 '17 at 21:17

add a comment |

up vote
17
down vote

PowerTOP from Intel allows you to toggle devices such as usb peripherals in real-time. These are called 'tunables'.

sudo apt install powertop

sudo powertop

Tab over to 'tunables'.

Scroll down to your device.

Hit enter to toggle power saving mode (Good/Bad)

enter image description here

Note that Bad means the device is always on. Toggling to Good will turn off the device after the preset inactive saving time (default is 2000ms).

See the PowerTOP docs for details on how to make these changes permanent.
It generates the config scripts for you (pretty much as described by other posters on this thread).

edited Jun 27 '17 at 22:41

answered May 6 '16 at 5:54

Dominic Cerisano

1,3811731

2

Awesome! :D I think this is the userfriendliest way to do it (although on low level it makes the same operations as outlined in the other answers.) Thank you, and may your answer reach the top ;)
– Matyas
May 9 '16 at 9:03

1

Thanks for your answer. Where do I have to start digging to change the preset inactive saving time?
– mikezter
Dec 21 '16 at 11:55

As mentioned by previous posters, kernel docs are here: kernel.org/doc/Documentation/usb/power-management.txt
– Dominic Cerisano
Mar 9 '17 at 21:17

add a comment |

up vote
17
down vote

PowerTOP from Intel allows you to toggle devices such as usb peripherals in real-time. These are called 'tunables'.

sudo apt install powertop

sudo powertop

Tab over to 'tunables'.

Scroll down to your device.

Hit enter to toggle power saving mode (Good/Bad)

enter image description here

Note that Bad means the device is always on. Toggling to Good will turn off the device after the preset inactive saving time (default is 2000ms).

See the PowerTOP docs for details on how to make these changes permanent.
It generates the config scripts for you (pretty much as described by other posters on this thread).

edited Jun 27 '17 at 22:41

answered May 6 '16 at 5:54

Dominic Cerisano

1,3811731

PowerTOP from Intel allows you to toggle devices such as usb peripherals in real-time. These are called 'tunables'.

sudo apt install powertop

sudo powertop

Tab over to 'tunables'.

Scroll down to your device.

Hit enter to toggle power saving mode (Good/Bad)

enter image description here

Note that Bad means the device is always on. Toggling to Good will turn off the device after the preset inactive saving time (default is 2000ms).

See the PowerTOP docs for details on how to make these changes permanent.
It generates the config scripts for you (pretty much as described by other posters on this thread).

edited Jun 27 '17 at 22:41

answered May 6 '16 at 5:54

Dominic Cerisano

1,3811731

edited Jun 27 '17 at 22:41

answered May 6 '16 at 5:54

Dominic Cerisano

1,3811731

answered May 6 '16 at 5:54

Dominic Cerisano

1,3811731

answered May 6 '16 at 5:54

Dominic Cerisano

1,3811731

2

Awesome! :D I think this is the userfriendliest way to do it (although on low level it makes the same operations as outlined in the other answers.) Thank you, and may your answer reach the top ;)
– Matyas
May 9 '16 at 9:03

1

Thanks for your answer. Where do I have to start digging to change the preset inactive saving time?
– mikezter
Dec 21 '16 at 11:55

As mentioned by previous posters, kernel docs are here: kernel.org/doc/Documentation/usb/power-management.txt
– Dominic Cerisano
Mar 9 '17 at 21:17

add a comment |

2

Awesome! :D I think this is the userfriendliest way to do it (although on low level it makes the same operations as outlined in the other answers.) Thank you, and may your answer reach the top ;)
– Matyas
May 9 '16 at 9:03

1

Thanks for your answer. Where do I have to start digging to change the preset inactive saving time?
– mikezter
Dec 21 '16 at 11:55

As mentioned by previous posters, kernel docs are here: kernel.org/doc/Documentation/usb/power-management.txt
– Dominic Cerisano
Mar 9 '17 at 21:17

Awesome! :D I think this is the userfriendliest way to do it (although on low level it makes the same operations as outlined in the other answers.) Thank you, and may your answer reach the top ;)
– Matyas
May 9 '16 at 9:03

Thanks for your answer. Where do I have to start digging to change the preset inactive saving time?
– mikezter
Dec 21 '16 at 11:55

As mentioned by previous posters, kernel docs are here: kernel.org/doc/Documentation/usb/power-management.txt
– Dominic Cerisano
Mar 9 '17 at 21:17

add a comment |

up vote
7
down vote

answered May 20 '12 at 10:25

Carles

10111

add a comment |

up vote
7
down vote

answered May 20 '12 at 10:25

Carles

10111

add a comment |

up vote
7
down vote

answered May 20 '12 at 10:25

Carles

10111

answered May 20 '12 at 10:25

Carles

10111

answered May 20 '12 at 10:25

Carles

10111

answered May 20 '12 at 10:25

Carles

10111

answered May 20 '12 at 10:25

Carles

10111

add a comment |

up vote
7
down vote

You could use uhubctl - command line utility to control USB power per port for compatible USB hubs.

Disclosure - I am the author of uhubctl.

edited May 20 at 3:58

answered Nov 8 '16 at 20:00

mvp

69.9k885122

fine tool on osx, but doesnt find any 'supported smart hub' on debian for me.
– jitter
Jan 7 at 23:13

1

On Linux, you need to either run it as root (under sudo), or to configure udev device permissions. It's also possible that your Linux host doesn't have compatible hubs connected.
– mvp
Jan 7 at 23:15

it's a 'beagle bone green' btw.
– jitter
Jan 11 at 1:55

add a comment |

up vote
7
down vote

You could use uhubctl - command line utility to control USB power per port for compatible USB hubs.

Disclosure - I am the author of uhubctl.

edited May 20 at 3:58

answered Nov 8 '16 at 20:00

mvp

69.9k885122

fine tool on osx, but doesnt find any 'supported smart hub' on debian for me.
– jitter
Jan 7 at 23:13

1

On Linux, you need to either run it as root (under sudo), or to configure udev device permissions. It's also possible that your Linux host doesn't have compatible hubs connected.
– mvp
Jan 7 at 23:15

it's a 'beagle bone green' btw.
– jitter
Jan 11 at 1:55

add a comment |

up vote
7
down vote

You could use uhubctl - command line utility to control USB power per port for compatible USB hubs.

Disclosure - I am the author of uhubctl.

edited May 20 at 3:58

answered Nov 8 '16 at 20:00

mvp

69.9k885122

You could use uhubctl - command line utility to control USB power per port for compatible USB hubs.

Disclosure - I am the author of uhubctl.

edited May 20 at 3:58

answered Nov 8 '16 at 20:00

mvp

69.9k885122

edited May 20 at 3:58

answered Nov 8 '16 at 20:00

mvp

69.9k885122

answered Nov 8 '16 at 20:00

mvp

69.9k885122

answered Nov 8 '16 at 20:00

mvp

69.9k885122

fine tool on osx, but doesnt find any 'supported smart hub' on debian for me.
– jitter
Jan 7 at 23:13

1

On Linux, you need to either run it as root (under sudo), or to configure udev device permissions. It's also possible that your Linux host doesn't have compatible hubs connected.
– mvp
Jan 7 at 23:15

it's a 'beagle bone green' btw.
– jitter
Jan 11 at 1:55

add a comment |

fine tool on osx, but doesnt find any 'supported smart hub' on debian for me.
– jitter
Jan 7 at 23:13

1

On Linux, you need to either run it as root (under sudo), or to configure udev device permissions. It's also possible that your Linux host doesn't have compatible hubs connected.
– mvp
Jan 7 at 23:15

it's a 'beagle bone green' btw.
– jitter
Jan 11 at 1:55

fine tool on osx, but doesnt find any 'supported smart hub' on debian for me.
– jitter
Jan 7 at 23:13

On Linux, you need to either run it as root (under sudo), or to configure udev device permissions. It's also possible that your Linux host doesn't have compatible hubs connected.
– mvp
Jan 7 at 23:15

it's a 'beagle bone green' btw.
– jitter
Jan 11 at 1:55

add a comment |

up vote
5
down vote

echo '2-1' |sudo tee /sys/bus/usb/drivers/usb/unbind

works for ubuntu

edited Apr 12 '14 at 17:05

mustaccio

14k83637

answered Apr 12 '14 at 16:46

user3527264

5111

YOURS IS THE ONLY SOLUTION THAT WORKED ON MY CASE. I am using an acer make laptop 12.04LTS Ubuntu.
– RicoRicochet
Dec 12 '14 at 5:57

Doesn't poweroff the device, only removes it from the device list. How can I poweroff the USB port?
– rustyx
Dec 20 '14 at 15:11

This is also the only solution that worked for me for powering off a Wacom Intuos5 touch M tablet without unplugging it (on Fedora 28)
– user1738984
Sep 11 at 10:50

add a comment |

up vote
5
down vote

echo '2-1' |sudo tee /sys/bus/usb/drivers/usb/unbind

works for ubuntu

edited Apr 12 '14 at 17:05

mustaccio

14k83637

answered Apr 12 '14 at 16:46

user3527264

5111

YOURS IS THE ONLY SOLUTION THAT WORKED ON MY CASE. I am using an acer make laptop 12.04LTS Ubuntu.
– RicoRicochet
Dec 12 '14 at 5:57

Doesn't poweroff the device, only removes it from the device list. How can I poweroff the USB port?
– rustyx
Dec 20 '14 at 15:11

This is also the only solution that worked for me for powering off a Wacom Intuos5 touch M tablet without unplugging it (on Fedora 28)
– user1738984
Sep 11 at 10:50

add a comment |

up vote
5
down vote

echo '2-1' |sudo tee /sys/bus/usb/drivers/usb/unbind

works for ubuntu

edited Apr 12 '14 at 17:05

mustaccio

14k83637

answered Apr 12 '14 at 16:46

user3527264

5111

echo '2-1' |sudo tee /sys/bus/usb/drivers/usb/unbind

works for ubuntu

edited Apr 12 '14 at 17:05

mustaccio

14k83637

answered Apr 12 '14 at 16:46

user3527264

5111

edited Apr 12 '14 at 17:05

mustaccio

14k83637

edited Apr 12 '14 at 17:05

mustaccio

14k83637

edited Apr 12 '14 at 17:05

mustaccio

14k83637

answered Apr 12 '14 at 16:46

user3527264

5111

answered Apr 12 '14 at 16:46

user3527264

5111

answered Apr 12 '14 at 16:46

user3527264

5111

YOURS IS THE ONLY SOLUTION THAT WORKED ON MY CASE. I am using an acer make laptop 12.04LTS Ubuntu.
– RicoRicochet
Dec 12 '14 at 5:57

Doesn't poweroff the device, only removes it from the device list. How can I poweroff the USB port?
– rustyx
Dec 20 '14 at 15:11

This is also the only solution that worked for me for powering off a Wacom Intuos5 touch M tablet without unplugging it (on Fedora 28)
– user1738984
Sep 11 at 10:50

add a comment |

YOURS IS THE ONLY SOLUTION THAT WORKED ON MY CASE. I am using an acer make laptop 12.04LTS Ubuntu.
– RicoRicochet
Dec 12 '14 at 5:57

Doesn't poweroff the device, only removes it from the device list. How can I poweroff the USB port?
– rustyx
Dec 20 '14 at 15:11

This is also the only solution that worked for me for powering off a Wacom Intuos5 touch M tablet without unplugging it (on Fedora 28)
– user1738984
Sep 11 at 10:50

YOURS IS THE ONLY SOLUTION THAT WORKED ON MY CASE. I am using an acer make laptop 12.04LTS Ubuntu.
– RicoRicochet
Dec 12 '14 at 5:57

Doesn't poweroff the device, only removes it from the device list. How can I poweroff the USB port?
– rustyx
Dec 20 '14 at 15:11

This is also the only solution that worked for me for powering off a Wacom Intuos5 touch M tablet without unplugging it (on Fedora 28)
– user1738984
Sep 11 at 10:50

add a comment |

up vote
2
down vote

In other words, a combination of this switch tutorial and this tutorial on communicating via Serial libary to Arduino plugged in via USB.

answered Nov 24 '16 at 2:55

NoBugs

5,346857111

add a comment |

up vote
2
down vote

In other words, a combination of this switch tutorial and this tutorial on communicating via Serial libary to Arduino plugged in via USB.

answered Nov 24 '16 at 2:55

NoBugs

5,346857111

add a comment |

up vote
2
down vote

In other words, a combination of this switch tutorial and this tutorial on communicating via Serial libary to Arduino plugged in via USB.

answered Nov 24 '16 at 2:55

NoBugs

5,346857111

In other words, a combination of this switch tutorial and this tutorial on communicating via Serial libary to Arduino plugged in via USB.

answered Nov 24 '16 at 2:55

NoBugs

5,346857111

answered Nov 24 '16 at 2:55

NoBugs

5,346857111

answered Nov 24 '16 at 2:55

NoBugs

5,346857111

answered Nov 24 '16 at 2:55

NoBugs

5,346857111

add a comment |

up vote
0
down vote

echo 'on' | sudo tee /sys/bus/usb/devices/1-1/power/control

answered Jul 17 '17 at 8:51

WonderLand

3,19733759

add a comment |

up vote
0
down vote

echo 'on' | sudo tee /sys/bus/usb/devices/1-1/power/control

answered Jul 17 '17 at 8:51

WonderLand

3,19733759

add a comment |

up vote
0
down vote

echo 'on' | sudo tee /sys/bus/usb/devices/1-1/power/control

answered Jul 17 '17 at 8:51

WonderLand

3,19733759

echo 'on' | sudo tee /sys/bus/usb/devices/1-1/power/control

answered Jul 17 '17 at 8:51

WonderLand

3,19733759

answered Jul 17 '17 at 8:51

WonderLand

3,19733759

answered Jul 17 '17 at 8:51

WonderLand

3,19733759

answered Jul 17 '17 at 8:51

WonderLand

3,19733759

add a comment |

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