Nicba1010 / uhubctl

uhubctl - USB hub per-port power control

uhubctl

uhubctl is utility to control USB power per-port on smart USB hubs. Smart hub is defined as one that implements per-port power switching.

Original idea for this code was inspired by hub-ctrl.c by Niibe Yutaka: https://www.gniibe.org/development/ac-power-control-by-USB-hub

Compatible USB hubs

Note that very few hubs actually support per-port power switching. Some of them are no longer manufactured and can be hard to find.

This is list of known compatible USB hubs:

Manufacturer	Product	Ports	USB	VID:PID	Release	EOL
AmazonBasics	HU3641V1 (RPi issue)	4	3.0	2109:2811	2013
AmazonBasics	HU3770V1 (RPi issue)	7	3.0	2109:2811	2013
AmazonBasics	HU9003V1EBL, HUC9003V1EBL	7	3.1	2109:2817	2018
AmazonBasics	HU9002V1SBL, HU9002V1EBL, HU9002V1ESL	10	3.1	2109:2817	2018
AmazonBasics	HUC9002V1SBL, HUC9002V1EBL, HUC9002V1ESL	10	3.1	2109:2817	2018
AmazonBasics	U3-7HUB (only works for 1 charge port)	7	3.0	2109:2813	2020
Anker	AK-68ANHUB-BV7A-0004 (note)	7	3.0	2109:0812	2014
Apple	Thunderbolt Display 27" (internal USB hub)	6	2.0		2011	2016
Apple	USB Keyboard With Numeric Pad (internal USB hub)	3	2.0		2011
Asus	Z87-PLUS Motherboard (onboard USB hub)	4	3.0		2013	2016
Aukey	CB-C59	4	3.1	2109:2813	2017
B+B SmartWorx	UHR204	4	2.0	0856:DB00	2013
B+B SmartWorx	USH304	4	3.0	04B4:6506	2017
Basler	2000036234	4	3.0	0451:8046	2016
Belkin	F5U101	4	2.0	0451:2046	2005	2010
Buffalo	BSH4A05U3BK	4	3.0	05E3:0610	2015
Bytecc	BT-UH340	4	3.0	2109:8110	2010
Circuitco	Beagleboard-xM (internal USB hub)	4	2.0	0424:9514	2010
Club3D	CSV-3242HD Dual Display Docking Station	4	3.0	2109:2811	2015
CyberPower	CP-H420P	4	2.0	0409:0059	2004
Cypress	CY4608 HX2VL development kit	4	2.0	04B4:6570	2012
D-Link	DUB-H4 rev B (silver). Note: rev B4+ not supported	4	2.0	05E3:0605	2005	2010
D-Link	DUB-H4 rev D,E (black). Note: rev A,C,F not supported	4	2.0	05E3:0608	2012
D-Link	DUB-H7 rev A (silver)	7	2.0	2001:F103	2005	2010
D-Link	DUB-H7 rev D,E (black). Note: rev B,C,F not supported	7	2.0	05E3:0608	2012
Dell	P2416D 24" QHD Monitor (note)	4	2.0		2017
Dell	S2719DGF 27" WQHD Gaming-Monitor	5	3.1	0424:5734	2018
Dell	UltraSharp 1704FPT 17" LCD Monitor	4	2.0	0424:A700	2005	2015
Dell	UltraSharp U2415 24" LCD Monitor	5	3.0		2014
Delock	62537	4	3.1		2020
Delock	87445 (note)	4	2.0	05E3:0608	2009	2013
Elecom	U2H-G4S	4	2.0		2006	2011
ExSys	EX-1113HMS	16	3.1		2018
GlobalScale	ESPRESSObin SBUD102 V5	1	3.0	1D6B:0003	2017
Hardkernel	ODROID-C4 (note)	4	3.0		2020
Hawking Technology	UH214	4	2.0		2003	2008
IOI	U3H415E1	4	3.0		2012
j5create	JUH470 (works only in USB2 mode)	3	3.0	05E3:0610	2014
Juiced Systems	6HUB-01	7	3.0	0BDA:0411	2014	2018
LG Electronics	38WK95C-W monitor	4	3.0	0451:8142	2018
Lenovo	ThinkPad Ultra Docking Station (40A20090EU)	6	2.0	17EF:100F	2015
Lenovo	ThinkPad Ultra Docking Station (40AJ0135EU)	7	3.1	17EF:3070	2018
Lenovo	ThinkPad X200 Ultrabase 42X4963	3	2.0	17EF:1005	2008	2011
Lenovo	ThinkPad X6 Ultrabase 42W3107	4	2.0	17EF:1000	2006	2009
Lindy	USB serial converter 4 port	4	1.1	058F:9254	2008
Linksys	USB2HUB4 (note)	4	2.0		2004	2010
Maplin	A08CQ	7	2.0	0409:0059	2008	2011
Microchip	EVB-USB2517	7	2.0		2008
Microchip	EVB-USB2534BC	4	2.0		2013
Moxa	Uport-407	7	2.0	110A:0407	2009
NVidia	Jetson Nano B01 (details)	4	3.0		2019
Phidgets	HUB0003_0	7	2.0	1A40:0201	2017
Plugable	USB3-HUB7BC	7	3.0	2109:0813	2015
Plugable	USB3-HUB7C (only works for 2 charge ports)	7	3.0	2109:0813	2015
Plugable	USB3-HUB7-81X	7	3.0	2109:0813	2012
Plugable	USB3-HUB10-C2 (only works for 2 charge ports)	10	3.0		2014
Port Inc	NWUSB01	4	1.1	0451:1446	1999	2003
Raspberry Pi	B+, 2B, 3B (see below)	4	2.0		2011
Raspberry Pi	3B+ (see below)	4	2.0	0424:2514	2018
Raspberry Pi	4B (see below)	4	3.0	2109:3431	2019
Renesas	uPD720202 PCIe USB 3.0 host controller	2	3.0		2013
Rosewill	RHUB-210	4	2.0	0409:005A	2011	2014
Rosonway	RSH-A16 (note)	16	3.2	0bda:0411	2020
Sanwa Supply	USB-HUB14GPH	4	1.1		2001	2003
Seagate	Backup Plus Hub STEL8000100	2	3.0	0BC2:AB44	2016
Sunix	SHB4200MA	4	2.0	0409:0058	2006	2009
Targus	PAUH212/PAUH212U	7	2.0		2004	2009
Texas Instruments	TUSB4041PAPEVM	4	2.1	0451:8142	2015
UUGear	MEGA4 (for Raspberry Pi 4B)	4	3.1	2109:0817	2021

This table is by no means complete. If your hub works with uhubctl, but is not listed above, please report it by opening new issue at https://github.com/mvp/uhubctl/issues, so we can add it to supported table. In your report, please provide exact product model and add output from uhubctl and please test VBUS off support as described below in FAQ.

Note that quite a few modern motherboards have built-in root hubs that do support this feature - you may not even need to buy any external hub.

USB 3.0 duality note

If you have USB 3.0 hub connected to USB3 upstream port, it will be detected as 2 independent virtual hubs: USB2 and USB3, and your USB devices will be connected to USB2 or USB3 virtual hub depending on their capabilities and connection speed. To control power for such hubs, it is necessary to turn off/on power on both USB2 and USB3 virtual hubs for power off/on changes to take effect. uhubctl will try to do this automatically (unless you disable this behavior with option -e).

Unfortunately, while most hubs will cut off data USB connection, some may still not cut off VBUS to port, which means connected phone may still continue to charge from port that is powered off by uhubctl.

Compiling

This utility was tested to compile and work on Linux (Ubuntu/Debian, Redhat/Fedora/CentOS, Arch Linux, Gentoo, openSUSE, Buildroot), FreeBSD, NetBSD, SunOS and MacOS.

While uhubctl compiles on Windows, USB power switching does not work on Windows because libusb is using winusb.sys driver, which according to Microsoft does not support necessary USB control requests. This may be fixed if libusb starts supporting different driver on Windows.

Note that it is highly recommended to have pkg-config installed (many platforms provide it by default).

First, you need to install library libusb-1.0 (version 1.0.12 or later, 1.0.16 or later is recommended):

• Ubuntu: sudo apt-get install libusb-1.0-0-dev
• Redhat: sudo yum install libusb1-devel
• MacOS: brew install libusb, or sudo port install libusb-devel
• FreeBSD: libusb is included by default
• NetBSD: sudo pkgin install libusb1 gmake pkg-config
• Windows: TBD?

To fetch uhubctl source and compile it:

git clone https://github.com/mvp/uhubctl
cd uhubctl
make

This should generate uhubctl binary. You can install it in your system as /usr/sbin/uhubctl using:

sudo make install

Note that on some OS (e.g. FreeBSD/NetBSD) you need to use gmake instead to build.

Also, on MacOS you can install uhubctl with all necessary dependencies in one shot using Homebrew tap:

brew tap mvp/uhubctl https://github.com/mvp/uhubctl
brew install uhubctl

To build/install from master branch, use --HEAD:

brew install uhubctl --HEAD

Usage

⚠️ On Linux, use sudo or configure USB permissions as described below!

To list all supported hubs:

uhubctl

You can control the power on a USB port(s) like this:

uhubctl -a off -p 2

This means operate on default smart hub and turn power off (-a off, or -a 0) on port 2 (-p 2). Supported actions are off/on/cycle/toggle (or 0/1/2/3). cycle means turn power off, wait some delay (configurable with -d) and turn it back on. Ports can be comma separated list, and may use - for ranges e.g. 2, or 2,4, or 2-5, or 1-2,5-8.

⚠️ Turning off built-in USB ports may cut off your keyboard or mouse, so be careful which ports you are turning off!

If you have more than one smart USB hub connected, you should choose specific hub to control using -l (location) parameter. To find hub locations, simply run uhubctl without any parameters. Hub locations look like b-x.y.z, where b is USB bus number, and x, y, z... are port numbers for all hubs in chain, starting from root hub for a given USB bus. This address is semi-stable - it will not change if you unplug/replug (or turn off/on) USB device into the same physical USB port (this method is also used in Linux kernel).

Linux USB permissions

On Linux, you should configure udev USB permissions (otherwise you will have to run it as root using sudo uhubctl). To fix USB permissions, first run sudo uhubctl and note all vid:pid for hubs you need to control. Then, add one or more udev rules like below to file /etc/udev/rules.d/52-usb.rules (replace 2001 with your vendor id):

SUBSYSTEM=="usb", ATTR{idVendor}=="2001", MODE="0666"

Note that for USB3 hubs, some hubs use different vendor ID for USB2 vs USB3 components of the same chip, and both need permissions to make uhubctl work properly. E.g. for Raspberry Pi 4B, you need to add these 2 lines:

SUBSYSTEM=="usb", ATTR{idVendor}=="2109", MODE="0666"
SUBSYSTEM=="usb", ATTR{idVendor}=="1d6b", MODE="0666"

If you don't like wide open mode 0666, you can restrict access by group like this:

SUBSYSTEM=="usb", ATTR{idVendor}=="2001", MODE="0664", GROUP="dialout"

and then add permitted users to dialout group:

sudo usermod -a -G dialout $USER

For your udev rule changes to take effect, reboot or run:

sudo udevadm trigger --attr-match=subsystem=usb

FAQ

What is USB per-port power switching?

According to USB 2.0 specification, USB hubs can advertise no power switching, ganged (all ports at once) power switching or per-port (individual) power switching. Note that by default uhubctl will only detect USB hubs which support per-port power switching (but you can force it to try operating on unsupported hubs with option -f). You can find what kind of power switching your hardware supports by using sudo lsusb -v:

No power switching:

wHubCharacteristic 0x000a
  No power switching (usb 1.0)
  Per-port overcurrent protection

Ganged power switching:

wHubCharacteristic 0x0008
  Ganged power switching
  Per-port overcurrent protection

Per-port power switching:

wHubCharacteristic 0x0009
  Per-port power switching
  Per-port overcurrent protection

How do I check if my USB hub is supported by uhubctl?

1. Run sudo uhubctl. If your hub is not listed, it is not supported. Alternatively, you can run sudo lsusb -v and check for Per-port power switching - if you cannot see such line in lsusb output, hub is not supported.
2. Check for VBUS (voltage) off support: plug a phone, USB light or USB fan into USB port of your hub. Try using uhubctl to turn power off on that port, and check that phone stops charging, USB light stops shining or USB fan stops spinning. If VBUS doesn't turn off, your hub manufacturer did not include circuitry to actually cut power off. Such hub would still work to cut off USB data connection, but it cannot turn off power, and we do not consider this supported device.
3. If tests above were successful, please report your hub by opening new issue at https://github.com/mvp/uhubctl/issues, so we can add it to list of supported devices. Please do not report unsupported hubs, unless it is different hardware revision of some already listed supported model.

USB devices are not removed after port power down on Linux

After powering down USB port, udev does not get any event, so it keeps the device files around. However, trying to access the device files will lead to an IO error.

This is Linux kernel issue. It may be eventually fixed in kernel, see more discussion here. Basically what happens here is that kernel USB driver knows about power off, but doesn't send notification about it to udev.

You can use this workaround for this issue:

sudo uhubctl -a off -l ${location} -p ${port}
sudo udevadm trigger --action=remove /sys/bus/usb/devices/${location}.${port}/

Device file will be removed by udev, but USB device will be still visible in lsusb. Note that path /sys/bus/usb/devices/${location}.${port} will only exist if device was detected on that port. When you turn power back on, device should re-enumerate properly (no need to call udevadm again).

Power comes back on after few seconds on Linux

Some device drivers in kernel are surprised by USB device being turned off and automatically try to power it back on.

You can use option -r N where N is some number from 10 to 1000 to fix this - uhubctl will try to turn power off many times in quick succession, and it should suppress that. This may be eventually fixed in kernel, see more discussion here.

Disabling USB authorization for device in question before turning power off with uhubctl should help:

echo 0 > sudo tee /sys/bus/usb/devices/${location}.${port}/authorized

If your device is USB mass storage, invoking udisksctl before calling uhubctl should help too:

sudo udisksctl power-off --block-device /dev/disk/...`
sudo uhubctl -a off ...

Multiple 4-port hubs are detected, but I only have one 7-port hub connected

Many hub manufacturers build their USB hubs using basic 4 port USB chips. E.g. to make 7 port hub, they daisy-chain two 4 port hubs - 1 port is lost to daisy-chaining, so it makes it 4+4-1=7 port hub. Similarly, 10 port hub could be built as 3 4-port hubs daisy-chained together, which gives 4+4+4-2=10 usable ports.

Note that you should never try to change power state for ports used to daisy-chain internal hubs together. Doing so will confuse internal hub circuitry and will cause unpredictable behavior.

Raspberry Pi turns power off on all ports, not just the one I specified

This is the limitation of Raspberry Pi hardware design. As a workaround, you can buy any external USB hub from supported list above, attach it to any USB port of Raspberry Pi, and control power on its ports independently. Also, there are supported hubs designed specifically for Raspberry Pi, e.g. UUGear MEGA4.

For reference, supported Raspberry Pi models have following internal USB topology:

Raspberry Pi B+,2B,3B

• Single hub 1-1, ports 2-5 ganged, all controlled by port 2:

  uhubctl -l 1-1 -p 2 -a 0
  

  Trying to control ports 3,4,5 will not do anything. Port 1 controls power for Ethernet+WiFi.

Raspberry Pi 3B+

• Main hub 1-1, all 4 ports ganged, all controlled by port 2 (turns off secondary hub ports as well). Port 1 connects hub 1-1.1 below, ports 2 and 3 are wired outside, port 4 not wired.

  uhubctl -l 1-1 -p 2 -a 0
  

• Secondary hub 1-1.1 (daisy-chained to main): 3 ports, port 1 is used for Ethernet+WiFi, and ports 2 and 3 are wired outside.

Raspberry Pi 4B

⚠️ If your VL805 firmware is older than 00137ad (check with sudo rpi-eeprom-update), you have to update firmware to make power switching work on RPi 4B.

• USB2 hub 1, 1 port, only connects hub 1-1 below.

• USB2 hub 1-1, 4 ports ganged, dual to USB3 hub 2 below:

  uhubctl -l 1-1 -a 0
  

• USB3 hub 2, 4 ports ganged, dual to USB2 hub 1-1 above:

  uhubctl -l 2 -a 0
  

• USB2 hub 3, 1 port, OTG controller. Power switching is not supported.

Notable projects using uhubctl

Project	Description
Morse code USB light	Flash a message in Morse code with USB light
Webcam USB light	Turn on/off LED when webcam is turned on/off
Cinema Lightbox	Turn on/off Cinema Lightbox from iOS Home app
Build Status Light	Create a build status light in under 10 minutes
Buildenlights	GitLab/GitHub project build status as green/red light
Weather Station	Reset Weather Station when it freezes
sysmoQMOD	Reset cellular modems when necessary
Smog Sensor	Raspberry Pi based smog sensor power reset
Terrible Cluster	Power on/off Raspberry Pi cluster nodes as needed
Ideal Music Server	Turn off unused USB ports to improve audio quality
USB drives with no phantom load	Power USB drives only when needed to save power
USB drive data recovery	Recover data from failing USB hard drive
Control power to 3D printer	OctoPrint web plugin for USB power control
USB fan for Raspberry Pi	Control USB fan to avoid Raspberry Pi overheating
Raspberry Pi Reboot Router	Automatically reboot router if internet isn't working
Control USB Lamp With Voice	Voice Control of USB Lamp using Siri and Raspberry Pi
Control USB LED Strip	Controlling USB powered LED Light Strip
Brew beer with Raspberry Pi	Automated beer brewing system using Raspberry Pi
Webcam On-Air Sign	Automatically light up a sign when webcam is in use
Do it yourself PPPS	Solder wires in your USB hub to support uhubctl

Copyright

Copyright (C) 2009-2020 Vadim Mikhailov

This file can be distributed under the terms and conditions of the GNU General Public License version 2.