OTG configuration is broken on omap kernel

[Oliver Grawert]

after first boot after doing a netinstall to SD card (with powered hub, keyboard and asix USB->ETH adapter attached to the board) the kernel spills an OOPS message on first boot, apparently related to OTG.

[Amit Kucheria (amitk)]

We should try to fix this for Lucid if possible. We were just not able to get the right config working in time for Lucid.

[Bryan Wu (cooloney)]

From the dmesg.txt from Oliver, I think we missed compile in the OTG transceiver driver into the kernel. So I prepared a kernel including that:
http://kernel.ubuntu.com/git?p=roc/ubuntu-lucid.git;a=shortlog;h=refs/heads/lp566645_otg

And the kernel package here:
http://people.canonical.com/~roc/kernel/lp566645_otg/

Please help me to test that.
Thanks,
-Bryan

[Mathieu Poirier (mathieu.poirier-deactivatedaccount)]

Bryan,

To get the OTG port in host mode one needs to ground the ID pin,
something that requires a soldering iron. Unless I find a way to do it
without the modification it will take me a couple of days to test your
image.

I will also get in touch with Oliver - after all he reported the problem
so I assume his board already has OTG enabled.

Cheers, Mathieu.

On Tue, 2010-06-15 at 10:35 +0000, Bryan Wu wrote:
> >From the dmesg.txt from Oliver, I think we missed compile in the OTG transceiver driver into the kernel. So I prepared a kernel including that:
> http://kernel.ubuntu.com/git?p=roc/ubuntu-lucid.git;a=shortlog;h=refs/heads/lp566645_otg
>
> And the kernel package here:
> http://people.canonical.com/~roc/kernel/lp566645_otg/
>
> Please help me to test that.
> Thanks,
> -Bryan
>

[Tobin Davis (gruemaster)]

A simple way to do this is to use a USB Mini A cable. USB Mini B cables are the more common type found, usually with cell phones and mp3 players. The Mini A cable will have a mini plug on one end and a USB Host plug for plugging in a keyboard or other device. See http://www.electronicproductonline.com/catalog/product_info.php?products_id=2043

[Bryan Wu (cooloney)]

Mathieu,

As Tobin said, you can just buy a USB OTG cable which provide Mini A and Mini B connectors. And insert the Mini A to the Beagle board OTG Mini AB port. When kernel boots, the USB OTG will be set as host. The Mini A connector contains such ID pin connection.

I will find my USB OTG cable provider and tell you later.
-Bryan

[Ricardo Salveti (rsalveti)]

I also got this issue with Lucid 2.6.33-502-omap, but this is not something that you can reproduce on every boot, as some times it does works correctly.

Still going to try with latest Maverick and upstream kernel to see if it's already fixed.

[Ricardo Salveti (rsalveti)]

For Maverick's kernel the OTG doesn't even work as Lucid's kernel.

Before plugging in the cable:
root@ubuntu-desktop:~# cat /sys/devices/platform/musb_hdrc/mode
b_idle

After plugging the cable:
root@ubuntu-desktop:~# cat /sys/devices/platform/musb_hdrc/mode
a_idle

echo host > /sys/devices/platform/musb_hdrc/mode also doesn't make any difference.

I'm now trying upstream kernel to see if works.

[Ricardo Salveti (rsalveti)]

With Maverick it does work if I compile the kernel with the following config file:
 * http://bazaar.launchpad.net/~beagleboard-kernel/+junk/2.6.35-devel/annotate/head:/patches/defconfig

It's quite different from Maverick's one, so still need to compare most of the changes related with usb and see what we should change to have the OTG behavior working again.

Brian, you can easily build and test with your board, to see how it should behave.

[Ricardo Salveti (rsalveti)]

For Maverick I opened bug 608312, because the basic functionality is not working yet.

[Bryan Wu (cooloney)]

When we built-in twl4030_usb module, this OOPS will be gone.

Please find the patches here:
http://kernel.ubuntu.com/git?p=roc/ubuntu-lucid.git;a=commitdiff;h=fc58ea3748869d2fa811dff26aa0fa07490b22b2

And kernel package here:
http://people.canonical.com/~roc/kernel/lp566645_otg/

These are for lucid, Maverick version will come soon

Thanks

[Ricardo Salveti (rsalveti)]

Tobin, can you please test this kernel and see if this bug is actually gone? Also make sure that the OTG works as expected.

Thanks in advance.

[Bryan Wu (cooloney)]

Please find the Maverick kernel here:
http://people.canonical.com/~roc/kernel/lp566645_otg/

I tested it on Gumstix board as well as Beagle board, it works.

Git patches:
http://kernel.ubuntu.com/git?p=roc/ubuntu-maverick.git;a=shortlog;h=refs/heads/otg

[Leann Ogasawara (leannogasawara)]

This should be Fixed in Maverick with the recent 2.6.35-16.22 kernel. This still appears to be open and under consideration for Lucid.

[Ricardo Salveti (rsalveti)]

Tobin, any chance to test the possible fixes?

[Tobin Davis (gruemaster)]

Tested in Maverick. No more errors. Also tested in Lucid. No errors.