UVC webcam not working with BBB

[vbmithr]

Hi,

For some reason, I can't use a UVC camera on my BBB with latest kernel (Linux alarm 3.12.0-rc2-1-ARCH #1 SMP Wed Sep 25 17:23:54 CDT 2013 armv7l GNU/Linux).

On the net there are several forums where people have such difficulties: [1]

It seems that this is due to a bug in the kernel regarding USB DMA, some people says it work with USB DMA activated, some deactivated.

I have tried to play with the kernel config but could not find how to change the CONFIG_MUSB_PIO_ONLY.
Basically, when I do make nconfig, it seems that this option is unchangeable. So I'm stuck here for now.

In order to reproduce the UVC webcam problem, this is quite simple:

1. Use BBB/archlinuxarm and do a pacman -Suy
2. git clone git://linuxtv.org/v4l-utils.git
3. cd v4l-utils && autoreconf --install && configure && make
4. cd contrib/test && ./capture-example
5. Observe that the program fails with a "select timeout" message, instead of capturing an image.

Thank you,

Vincent

[1]: https://groups.google.com/forum/#!searc ... eboard/UVC