usb issues

GoogleGroups
1

hi

I am having the USB lockup issue on EHCI. seems to be triggered by
intensive cpu usage, or usb traffic. i get the following in dmesg
[48262.074157] hub 1-0:1.0: port 2 disabled by hub (EMI?), re-
enabling...
[48262.094451] usb 1-2: USB disconnect, address 2
[48262.094482] usb 1-2.1: USB disconnect, address 3
[48262.094726] usb 1-2: clear tt 1 (9031) error -71
[48262.115234] usb 1-2: clear tt 1 (9031) error -19
[48262.128662] usb 1-2: clear tt 1 (9031) error -19
[48262.145843] usb 1-2: clear tt 1 (9031) error -19
[48262.161590] eth0: unregister 'dm9601' usb-ehci-omap.0-2.1, Davicom
DM9601 USB Ethernet
[48263.474487] usb 1-2.4: USB disconnect, address 4

and then nothing on USB will work anymore. this seem to be a widely
reported issue.

i was wondering if the mini usb port (OTG) is also effected? I have
tried pluging my hub into that via a couple of different usb gender
changers, but the board does not see any devices. looks like i need to
do soldering to make it act as a host (is that right?).

if i do the soldering will i get a stable USB port? or should i just
RMA the board (bit of a pain as I am in the UK)

Sam

2

This does not affect the OTG.

This is a very well known issue EHCI port issue…

You can send it in for an RMA and we will attach a 22uf capacitor across C97.

Or, you can add the capacitor youself if you like.

Gerald

3

This does not affect the OTG.

This is a very well known issue EHCI port issue…

You can send it in for an RMA and we will attach a 22uf capacitor across C97.

Or, you can add the capacitor youself if you like.

Just remember to use a 22uF SMD ceramic cap with a low ESR.

Gerald, you might want to specify a part number, or a package size and ESR limit.

Gerald

4

The capacitor can be SMT or thruhole. ESR is not super critical in this case, althogu lower is better, a higher value won’t cause any issues. After all, in this case you already have an issue. I really don’t want to get into providing a long list of parts and have to keep adding numbers because the parts I specify may not be available in a specific region. They can always send it in for an RMA and we will do it. Folks have had success soldering in a thru hole part, something more likley to be found, on the expansion connector as well across the 1.8V and ground pins on the expansion connector.

Gerald

5

Hi,

Which revision is affected with that issue?

Best regards,
Darko T.

6

C2 and C3. They are the only ones with the EHCI connector populated.

Gerald

7

Hello,

This does not affect the OTG.
This is a very well known issue EHCI port issue..

Does the EBVBeagle board have the same problem?

8

Possibly. Not all boards have this issue. Some work perfectly and other do not. It is likely that some EBV boards will have this issue.

Gerald

9

thanks

i got one of these.
http://www.keene.co.uk/electronic/unbranded/mini-usb-type-a-plug-to-usb-a-type-socket-adaptor/USBMINS.html
seems to be working. stable so far.

i needed make a /etc/rc2.d/S00usbhost
echo host> /sys/devices/platform/musb_hdrc/mode
sleep 5
to get it into host mode, and wait long enough to get dhcp before
starting services (mpd). /etc/rc.local is to late in the boot process.

sam

10

Hi,

thanks

i got one of these.
http://www.keene.co.uk/electronic/unbranded/mini-usb-type-a-plug-to-usb-a-type-socket-adaptor/USBMINS.html
seems to be working. stable so far.

I bought a mini-a => mini-b cable and i tried to link the bb to the
hub (which is self powered)

i needed make a /etc/rc2.d/S00usbhost
echo host> /sys/devices/platform/musb_hdrc/mode
sleep 5
to get it into host mode, and wait long enough to get dhcp before
starting services (mpd). /etc/rc.local is to late in the boot process.

Then i tried to create that file during the boot but it fault and the
bb doesn't see any hub or device..
I gave a look to the dmesg but there isn't nothing about usb interface..

Any ideas?

Thanks

Luca

11

make sure the script is executable
sam@beagleboard:~$ ls -l /etc/rc2.d/
-rwxr-xr-x 1 root root 86 2009-11-20 00:02 S00usbhost

you might need to do
sudo chmod +x /etc/rc2.d/S00usbhost

sam

12

it return me an error because there is no file with that name..

i think we are using a different version of kernel and something has changed..
what is yours? i'm using the unstable prebuild image of angstrom with
a 2.6.29 kernel..

thanks

13

i am using ubuntu with kernel 2.6.31.6-x6.0

14

Do I understand that I remove the C97 and give a capacity of 22uF
capacitor?

15

Do NOT remove C97. ADD the 22uf cap to C97. You can try adding it across C97 itself, or try adding it between the GND signal and the 1.8V rail on the expansion header.

Gerald