USB Issue Troubleshooting

[timhavens]

9600,

I did this exact thing this morning, and in fact the network worked fine (and the usb after some fiddling around)...some power cycles and such.

So 'it was working' and now after I 'shutdown -h now' then powered it down, and disconnected all cables from Parallella the USB has been back to giving me the -99 errors.

Just as I was typing this message I was trying something else...with the same hdmi kern/fpga installed. I powered the box down and connected my powered usb hub, only this time I didn't power the hub. SO power to the barrel connector on the Parallella and no power connected to my powered hub. And I see this:

"Welcome to Linaro 14.04 (GNU/Linux 3.12.0-g0bc9c3a-dirty armv7l)

* Documentation: https://wiki.linaro.org/
Last login: Wed Dec 3 22:17:53 2014 from 192.168.3.12
linaro@linaro-nano:~$ lsusb
Bus 001 Device 003: ID 1a40:0101 Terminus Technology Inc. 4-Port HUB
Bus 001 Device 002: ID 1a40:0201 Terminus Technology Inc. FE 2.1 7-port Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub"

So now I plug in an RTL (tv) dongle and lsusb says:

linaro@linaro-nano:~$ lsusb
Bus 001 Device 004: ID 0bda:2838 Realtek Semiconductor Corp. RTL2838 DVB-T
Bus 001 Device 003: ID 1a40:0101 Terminus Technology Inc. 4-Port HUB
Bus 001 Device 002: ID 1a40:0201 Terminus Technology Inc. FE 2.1 7-port Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

Notice the Dongle shows up. This is still with the powered usb hub (UN-POWERED).

I've heard of usb ports that don't like to see any return voltage coming from powered hubs at init time. (dunno why really, seems some things are ok with that and some aren't)....

Anyway...that's where I am with this now.

1.) the network has started up every time with the HDMI kern/fpga.
2.) the usb has started up 2 times now with the same as above.

Hope this helps? And thanks for you response.

[timhavens]

By the way, I'd been seeing constant respawns mentioning hvc0.

I also went into /etc/securetty and remarked out 'hvc0' and 'hvc1' which I don't think are required (but I could be mistaken). The respawns have stopped after a hard reboot. (ie. shutdown, power cycled).

Those respawns where happened a few times a second prior to this change.

In the back of my mind I was wondering if these were interfering with usb init...so figured it was worth a shot to remark them out and try.

[9600]

Thanks for the feedback, it's much appreciated, and great to hear that you have resolved the USB issue!

As for the USB powered hub, that is strange. I would have thought that if it is compliant it would not send power back up to the host.

I had to look up what hvc devices are for and since it turns out it's Xen hypervisor console, I certainly shouldn't have thought we'd need them. And if they were trying to write to the serial console as USB initialises, I guess it's possible they could effect it, as it becomes unstable when the serial console is enabled (as is the case with the default headless kernel/devicetree, but not the HDMI one, which has console on UART disabled). Although it could be a red herring, but good to get rid of errors in any case!

Regards,

Andrew

[timhavens]

Andrew,

Thanks for your comments and ideas. I wouldn't say that I've "resolved the USB issue" it's still picky about how things are started up, and I'm trying to narrow down a working sequence vs. a sequence that doesn't work.

[zmc]

My personal experience, hope it helps someone.

I've had my parallella since they were made publically available, and have been using it as my primary workstation for almost as long. I have had some usb issues intermitantly, but usually a powercycle fixes it.

Here's what was connected to my 1.5A powered compliant USB hub

Power to parallella
Power to hacked 12v mini powersupply fan (running with 5v is quiet, and keeps the parallella quite cool, even in PR)
Power to mini-hdmi to VGA converter
5 SanDisk Cruzer USB flash drives (LVM Raid, and storing almost all my filesystem)
SoundBlaster X-Fi Go Sound Card
Fujitsu FI Flatbed/ADF Scanner
Generic USB Bluetooth PHY
Model M Keyboard
Logitech Wired G-series Mouse

Occasionally I connect a Sony PS Eye webcam/microphone, some other flash drives, or an Arduino or 2.

The parallella sometimes crashes the USB bus when starting X, and periodically in a non load dependent way.
When the bus crashes, my filesystems are unavailable, so are my input devices, and it's generally a trainwreck.

I was in the middle of doing something I cared about, and the bus crashed on me, so this problem has come into the crosshairs.

To eliminate the power-to-parallella aspect, I created a 5v power source to the barrel connector, rated for 10A instead of powering it from the 1.5A rated hub. This worsened the problem! The USB would crash often right after the filesystems were mounted (about the time the framebuffer sets the consolefont)

I then created an alternate 500ma power source for the fan and VGA adapter. This made the problem even worse still. The kernel would initialize the hub, and the usb bus would immediately crash. Warm resets, and plugging and unplugging the usb and hdmi cables would help a little but it was nearly impossible to reach a login with working usb. Main power source to parallella was tested to min 5.03v max 5.04v.

At this point the kernel was suggesting that I had a bad cable, so I tested with various cables, 2 different micro-usb to usb otg adapters, another powered hub, an unpowered hub, and finally just a keyboard attached with the same behavior.

Then I started backtracking. I moved the fan and hdmi adapter back to the powered hub, and again powered the parallella from the powered hub as well, and the system regained the usable stability I was used to.

The fact that unplugging and replugging the HDMI cable helps somehow, and that my least stable configuration was with the HDMI adapter on a seperate (underpowered) powersource, led me to believe that the fpga was getting confused with some kind of voltage on the HDMI port.

I started testing epiphany tests, I could get simple tests to run on the epiphany (adding numbers in a loop), but more complicated tasks (matmul-16) would hang.

My next step is to move the VGA adapter to the 10A powersource, to see what happens, but I think that somehow when my VGA adapter is underpowered it causes some problem in the Zync, and perhaps we have been looking at only part of the problem, since mostly USB users use HDMI as well.

I'll let you know what I find out. If anyone has any insight into this avenue of investigation, please let me know.

[nharrington]

[nharrington]

[ajtravis]

[piotr5]

I really know no electronics, but has anyone tried to monitor the power-consumption during start up? I mean, usb problems could be caused by too much power being used in a short time, so after an initial spike of power consumption, maybe there's another spike causing init-difficulties? in other words, according to my experience with computers the number one suspect for hardware-failure is power-input, number 2 would be heat, followed by humidity and/or dust. I saw each of these 3 make my devices malfunction already...

[ajtravis]