Login or Register to Ask a Question and Join Our Community

Sponsored Content
Full Discussion: USB power cycling poblem on RPI
Special Forums Hardware USB power cycling poblem on RPI Post 302935939 by vthielen on Friday 20th of February 2015 11:09:55 AM
Old 02-20-2015
USB power cycling poblem on RPI
I am having a problem with cycling USB bus power on the RPI B+ (3.18.7+).

Each time I power the USB bus off and on, a device plugged into it gets a higher Device number, and eventually the bus crashes (does not enumerate new devices any more)

As a demonstration, I wrote the python script at the bottom, which just turns the bus on and off and runs lsusb in an infinite loop.
I had trouble with a USB GSM modem, but even when I plug a simple TI launchpad (MSP430 experimenter board) in the bus, it will disappear after some cycles.

I have the impression that the USB controller or software thinks there are 82 devices on the bus, which is probably why it crashes.
Is there a way to completely reset the USB bus software/hardware so it will start counting from zero again?
Another solution would be a command that removes the device from the bus before I turn it off, so it would probably get the same Device number when it is switched on again.
I have tried without success:
- Increasing the sleep times in the script
- Running "/etc/init.d/udev restart"
- turning the entire hub off and on with "hub-ctrl -h 0 -p 0/1"
- “echo '1-1' | tee /sys/bus/usb/drivers/usb/unbind” (and re-bind afterwards)


The output of the python script when it starts to fail (after about 80 cycles) is:

Code:
Bus 001 Device 002: ID 0424:9514 Standard Microsystems Corp.
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 003: ID 0424:ec00 Standard Microsystems Corp.
Bus 001 Device 081: ID 0451:f432 Texas Instruments, Inc. eZ430 Development Tool
Bus 001 Device 002: ID 0424:9514 Standard Microsystems Corp.
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 003: ID 0424:ec00 Standard Microsystems Corp.
Bus 001 Device 082: ID 0451:f432 Texas Instruments, Inc. eZ430 Development Tool
Bus 001 Device 002: ID 0424:9514 Standard Microsystems Corp.
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 003: ID 0424:ec00 Standard Microsystems Corp.
Bus 001 Device 002: ID 0424:9514 Standard Microsystems Corp.
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 003: ID 0424:ec00 Standard Microsystems Corp.
Bus 001 Device 002: ID 0424:9514 Standard Microsystems Corp.
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub


the script itself is:

Code:
#!/usr/bin/python
from subprocess import call
import time

while True:
call(["hub-ctrl", "-h", "0", "-P", "2", "-p", "0"]) # turn off the USB modem
time.sleep(1)
call(["hub-ctrl", "-h", "0", "-P", "2", "-p", "1"]) # turn off the USB modem
time.sleep(2)
call(["lsusb"]) # print


When it (the modem) fails, I get the 4 lines below in the /var/log/messages file after unplugging and re plugging the device ONCE:
Code:
Feb 19 15:32:43 aardbei kernel: [ 8195.531922] usb 1-1.5: new full-speed USB device number 82 using dwc_otg
Feb 19 15:32:43 aardbei kernel: [ 8195.991933] usb 1-1.5: new full-speed USB device number 83 using dwc_otg
Feb 19 15:32:43 aardbei kernel: [ 8196.451884] usb 1-1.5: new full-speed USB device number 84 using dwc_otg
Feb 19 15:32:44 aardbei kernel: [ 8196.951966] usb 1-1.5: new full-speed USB device number 85 using dwc_otg

Posts: 20Joined: Wed Mar 05, 2014 9:32 am
Last edited by Don Cragun; 02-21-2015 at 03:07 AM.. Reason: Add CODE and ICODE tags.
 

8 More Discussions You Might Find Interesting

1. UNIX for Dummies Questions & Answers

Power Cycling

Hello Friends , I have been reading some of the Sys Admin notes when i came across a term "Power Cycling" Can anybody please explain what this means Thank You (1 Reply)
Discussion started by: DPAI
1 Replies

2. UNIX for Advanced & Expert Users

How Can I To Power Off My Computer?

I have a SCO UNIX 5.0.6. and a computer ATX. My Question is: How can i to power off my computer without to push the power button? :confused: Please help me. :( Thanks :) (1 Reply)
Discussion started by: vhabalos
1 Replies

3. AIX

How to tell Power 4/5/6

I'm looking for a way - from the command line - to tell whether a given AIX system I have is a Power5, Power4 or Power6 machine - it seems like there would be an option to 'uname' but I couldn't find one. Thanks! (3 Replies)
Discussion started by: thomn8r
3 Replies

4. Solaris

Poblem with libX11.so.4

good evening everyone i am getting this library problem with intel platform architec :confused: after installing the entire sun-5.10 with a hard configuration intel945chipset core2dual processor & 2GB ram with disk sapace of 40gb. after install the entire os my machine is rebooting... (1 Reply)
Discussion started by: ravinder singh
1 Replies

5. Shell Programming and Scripting

KSH switches editin modes when cycling through history. Why?

Hello all, Working in KSH using Solaris, the default editor is VIM. So, per session, I run a small rc script which calls export editor=emacs This works for commands at the prompt. But if I cycle through command history (Using the up arrow) the command line editor defaults to VIM. How can I... (2 Replies)
Discussion started by: eggmatters
2 Replies

6. Shell Programming and Scripting

WGET cycling on an updating page

Hello, I am experiencing an issue while downloading a few pages using wget. All of them work without a problem except one which is a page that does a tail on the log and as a result is constantly getting updated. wget here seems to run endlessly and needs to be manually killed. I wanted to... (0 Replies)
Discussion started by: prafulnama
0 Replies

7. UNIX for Dummies Questions & Answers

USB-USB cable between linux and windows computers

Is there an easy way to setup a cross-over cable (USB-USB) between a linux box and a windows PC? My 2 machines are next to each other but I really do not want to keep transfering my files using my USB drive. Thanks! (4 Replies)
Discussion started by: Xterra
4 Replies

8. IP Networking

Is bond0 ready and a bonding interface? - 4G Bonding Router Problems (RPI)

HI all, First post on the forum, and my first proper project on the Paspberry Pi, so sorry if this is in the wrong place. I am trying to turn my Pi in to a 3G/4G Bonding router. I have been researching and trying this for a week or so now. The basic plan is to have up to 6 ZTE MF823 USB... (0 Replies)
Discussion started by: elliottlc
0 Replies
All times are GMT -4. The time now is 01:23 AM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy