Turning off power to usb port. Or turn off power to entire usb subsystem
I have a usb lamp which I specifically bought in order to turn it off programmatically at a certain time, thus I need to remove the power to its usb port. I believe I have a usb-hub at usb6. The lamp is connected to one of the ports in this hub:
#myhost$ lsusb Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 006 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 007 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 008 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub . . Bus 008 Device 006: ID 050d:0234 Belkin Components F5U234 USB 2.0 4-Port Hub echo disabled > /sys/bus/usb/devices/usb1/power/wakeup echo suspend > /sys/bus/usb/devices/usb1/power/level # turn off but I get write error: Invalid argument when trying to write to /sys/bus/usb/devices/usb1/power/level :
$sudo bash -c 'echo disabled > /sys/bus/usb/devices/usb6/power/wakeup' $echo suspend|sudo tee /sys/bus/usb/devices/usb6/power/level suspend tee: /sys/bus/usb/devices/usb6/power/level: Invalid argument $sudo bash -c 'echo suspend> /sys/bus/usb/devices/usb6/power/level'bash: line 0: echo: write error: Invalid argument sudo bash -c 'echo 0 > /sys/bus/usb/devices/usb6/power/autosuspend_delay_ms; echo auto > /sys/bus/usb/devices/usb6/power/control' which does turn off power to the usb-hub device. I was also trying to follow this: But the output of lsusb -t just hangs:
$lsusb -t 4-1:0.0: No such file or directory 4-1:0.1: No such file or directory ^C echo '2-1.1' > /sys/bus/usb/drivers/usb/unbind Is there an alternative way of getting this information? Alternatively, is there a way to shut off power to the entire usb subsystem? Something like modprobe -r usb_etc ? My kernel is:
Power on/off USB ports
Is it possible to on/off a specific USB port using the terminal in Ubuntu? lsusb displays the following result:
Bus 001 Device 002: ID 8087:0020 Intel Corp. Integrated Rate Matching Hub Bus 002 Device 002: ID 8087:0020 Intel Corp. Integrated Rate Matching Hub Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 001 Device 003: ID 2232:1020 Bus 002 Device 009: ID 0bc2:a013 Seagate RSS LLC Bus 002 Device 003: ID 0a5c:219c Broadcom Corp. Seagate is my external hard disk drive. Can I power it off in the terminal? I tried Controlling a USB power supply (on/off) with Linux. But I am confused about what should be replaced in place of usbX .
4 Answers 4
All of the previous answers talk about a USB suspend mechanism, i.e. a «logical power-off», they will never physically cut the VBUS +5V from the USB port.
Only a few hubs can actually cut VBUS as described here.
The hubpower tool can do it (if the hub supports it).
After running into the same problem, I found that the commands should be entered differently so that «sudo» would apply rights appropriately.
echo 0 | sudo tee /sys/bus/usb/devices/usb2/power/autosuspend_delay_ms will apply root rights to the «tee» command which will write the 0 into the specified file, replacing anything that is currently there. To append, use the tee command with option -a.
for info see the man page of tee
The tee command will have the side effect of also printing to the screen. If you want, dd of=/sys/bus/. will write only to the file, and nowhere else.
Actually usbX is nothing but the USB ports numbers where X denotes the number like 1 or 2 and so on. For example, usb1 and usb2 for ports 1 and 2. In general, a laptop may have three or four USB ports with USB 2.0 and USB 3.0 ports.
In Ubuntu, usb1 , usb2 . usbX are the links to /sys/devices/pci000:00/* . To understand it well, run this command:
So to enable/disable USB ports usbX will be replaced with usb1 when you want to enable/disable USB Port Number 1 (or refer Stack Exchange):
Edit: Thanks to Stefan Denchev to tell the correct way to echo some text to a file using sudo. (Check his comment also.) You should not get the permission denied message now.
sudo sh -c "echo '0' > /sys/bus/usb/devices/usb1/power/autosuspend_delay_ms" sudo sh -c "echo 'auto' > /sys/bus/usb/devices/usb1/power/control" After seeing your lsusb result, it looks like your Seagate device is connected to Port No. 2 , so you need to disable usb2 . Then the commands would be:
sudo sh -c "echo '0' > /sys/bus/usb/devices/usb2/power/autosuspend_delay_ms" sudo sh -c "echo 'auto' > /sys/bus/usb/devices/usb2/power/control" Thanks. If I try echo «0» > «/sys/bus/usb/devices/usb2/power/autosuspend_delay_ms» the output is bash: /sys/bus/usb/devices/usb2/power/autosuspend_delay_ms: Permission denied
Actually I didn’t try to enable/disable any ports in Linux.. My motto was to make you clear about usbX problem. If you are much clear about the commands that you grabbed from StackOverflow then only you should give it a try. Any way now I am also interested to know which is actual command to enable/disable ports. I’ll reply you soon, when it works for me. Tell then you unplug your device and try again. or try the first answer given at stackoverflow .
udisksctl has power-off flag, which I suggest you use in conjunction with unmount
power-off Arranges for the drive to be safely removed and powered off. On the OS side this includes ensuring that no process is using the drive, then requesting that in-flight buffers and caches are committed to stable storage. The exact steps for powering off the drive depends on the drive itself and the interconnect used. For drives connected through USB, the effect is that the USB device will be deconfigured followed by disabling the upstream hub port it is connected to Here’s me unmounting my USB jumpdrive and then powering it off
testdir:$ lsusb Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 006 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 001 Device 009: ID 154b:007a PNY Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub testdir:$ lsblk NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT sda 8:0 0 111.8G 0 disk └─sda1 8:1 0 111.8G 0 part / sdb 8:16 1 30G 0 disk └─sdb1 8:17 1 30G 0 part /media/xieerqi/6A32C4555E1C5B4D sr0 11:0 1 1024M 0 rom testdir:$ udisksctl unmount -b /dev/sdb1 && udisksctl power-off -b /dev/sdb1 Unmounted /dev/sdb1. testdir:$ lsusb Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 006 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub testdir:$ lsblk NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT sda 8:0 0 111.8G 0 disk └─sda1 8:1 0 111.8G 0 part / sr0 11:0 1 1024M 0 rom testdir:$