Re: [Bug] 0ac8:0321 Vimicro generic vc0321 Camera is not working and causes crashes since 3.2

[Hans de Goede <hdegoede@redhat.com>]

Hi,

On 09/08/2013 01:37 PM, Frank Dierich wrote:
> Hi,
>
> I have an ASUS A8JP Notebook with Ubuntu 12.04 with the following build in webcam
>
>      Bus 001 Device 004: ID 0ac8:0321 Z-Star Microelectronics Corp. Vimicro generic vc0321 Camera
>
> The camera is working nice with Cheese and kernels before 3.2. I have tested the following once 2.6.32.61, 2.6.33.20, 2.6.34.11, 2.6.35.14, 2.6.36.4, 2.6.37.6, 2.6.38.8, 2.6.39.4, 3.0.94, 3.1.10. In all later kernels I have tested (3.2.50, 3.4.60, 3.10.10, 3.11.0) Cheese shows for some seconds a green and noisy image and crashes then with a segmentation fault.
>
> On the web I found some bug reports very similar to my problem but no one of these leads to a solution.
> http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=677533
> https://bugs.launchpad.net/ubuntu/+source/linux/+bug/990749
>
> In the following i give some informations about my system which hopefully helps to find the problem.

Thanks for the bug report, looking at the bug reports, they all report an error of -71 which is
EPROTO, which typically means something is wrong at the USB level.

And nothing has changed for the driver in question between 3.1 and 3.2 , so I believe this regression
is caused by changes to the usb sub-system, likely changes to the EHCI driver.

The best way forward with this is probably to bisect the problem, and then send a mail
to linux-usb@vger.kernel.org about this. Please CC me on this mail.

Regards,

Hans