I have a problem with the USB OTG port. For some reason, it reports
itself as a HUB, and therefore refuses any bus-powered hub- even if
the device is simply a keyboard with happens to have 2 USB ports that
I do not plan to use.
The EHCI port can't be used - I guess that's because the keyboard is not EHCI.
Is there a workaround to make the MUSB HDRC host driver work like a
USB master port, and not as a hub ??
BTW, why does the dmesg reports a 3 ports hub has been detected, even
when there's nothing connected ??
Thanks
Guylhem
--
Dr. Guylhem Aznar, MD PhD
Unité d'Analyse Médico-Économique
Service de Santé Publique et d'Économie de la Santé
Pôle SPSSR
CHU de Fort de France
BP 632
97261 Fort De France Cedex
Martinique, France
Tel : 05 96 55 23 47
Fax : 05 96 75 84 57
On Tue, May 26, 2009 at 12:10, John Beetem <johnb...@yahoo.com> wrote:
> The usual cause of this is using a Mini-B plug instead of a Mini-A
No, I'm using a mini A. To be sure it works fine, I did even shorted
the pins on the motherboard.
I can plug USb peripherals and they are detected.
However, my keyboard can not work because the kernel believes I'm
daisy-chaining 2 bus-powered hubs.
The keyboard has a hub, ok, but is the OTG port on an internal hub on
the beagleboard?
The kernel thinks so.
That would explain why the kernel refuses to accept the keyboard
because it's not a externally powered usb hub.
IMHO either :
- the OTG port is indeed on an internal hub, which then shouldn't be
declared as bus powered
- the OTG port is on no internal hub, and the reference should be removed
In any case it seems weird. Maybe a sysfs option to allow daisy
chaining bus-powered hubs, at the sole resposability of the user,
would be interesting.
Is it possible to modify/configure the kernel so that OTG always works
in host mode regardless of the status of ID pin? This would allow to use
Mini-B cable/adapter for OTG without any HW mods. Mini-A cables just do not
seem to be available in local shops.
I wonder if it would be possible to have Micro-AB plug for OTG in one of the
next revisions of beagleboard? Seems like Micro-A cables/adapters are much
easier to find. This has been already proposed on the list long ago:
http://groups.google.com/group/beagleboard/browse_thread/thread/4765b005528befce
--
Best regards,
Siarhei Siamashka