Re: zc3xx: "Creative Webcam Live!" never worked with in-tree driver

[Auke Kok <auke@foo-projects.org>]

Jean-Francois Moine wrote:
> On Tue, 24 Feb 2009 21:19:16 -0300
> Mauro Carvalho Chehab <mchehab@redhat.com> wrote:
>> On Tue, 24 Feb 2009 16:00:59 -0800
>> Auke Kok <auke@foo-projects.org> wrote:
>>
>>> Auke Kok wrote:
>>>> All,
>>>>
>>>> I have a "Creative Technology, Ltd Webcam Live!/Live! Pro" that
>>>> until recently worked fine with the out-of-tree gspcav1 driver 
>>>> (gspcav1-20071224.tar.gz is the latest version I used unti
>>>> 2.6.26).
>>>>
>>>> Since this driver (basically) got merged in the kernel I got my
>>>> hopes up that the in-kernel gspca_zc3xx drivers would work.
>>>> However, that does not provide a usable video0 device - mplayer
>>>> tv:// crashes with 'No stream found.' for instance:
>>>>
>>>> Playing tv://.
>>>> Cache fill:  0.00% (0 bytes)
>>>> TV file format detected.
>>>> Selected driver: v4l2
>>>>  name: Video 4 Linux 2 input
>>>>  author: Martin Olschewski <olschewski@zpr.uni-koeln.de>
>>>>  comment: first try, more to come ;-)
>>>> Selected device: WebCam Live!
>>>>  Capabilites:  video capture  read/write  streaming
>>>>  supported norms:
>>>>  inputs: 0 = zc3xx;
>>>>  Current input: 0
>>>>  Current format: unknown (0x4745504a)
>>>> tv.c: norm_from_string(pal): Bogus norm parameter, setting
>>>> default. v4l2: ioctl enum norm failed: Invalid argument
>>>> Error: Cannot set norm!
>>>> Selected input hasn't got a tuner!
>>>> v4l2: ioctl set mute failed: Invalid argument
>>>> v4l2: ioctl query control failed: Invalid argument
>>>> v4l2: ioctl query control failed: Invalid argument
>>>> FPS not specified in the header or invalid, use the -fps option.
>>>> No stream found.
>>>>
>>>> v4l2: ioctl set mute failed: Invalid argument
>>>> v4l2: 0 frames successfully processed, 0 frames dropped.
>>>>
>>>> Exiting... (End of file)
>>>>
>>>>
>>>> I've regressed back to the original import of the spca driver in
>>>> the kernel tree and this doesn't fix it, so I'm assuming that the
>>>> driver were not merged correctly for my particular device.
>>>>
>>>> Basically the driver probes and load fine as is right now, no
>>>> unusual message in dmesg as far as I can see:
>>>>
>>>> zc0301: V4L2 driver for ZC0301[P] Image Processor and Control
>>>> Chip v1:1.10 usbcore: registered new interface driver zc0301
>>>> usbcore: deregistering interface driver zc0301
>>>> gspca: probing 041e:4036
>>>> zc3xx: probe 2wr ov vga 0x0000
>>>> zc3xx: probe sensor -> 11
>>>> zc3xx: Find Sensor HV7131R(c)
>>>> gspca: probe ok
>>>> usbcore: registered new interface driver zc3xx
>>>> zc3xx: registered
>>>>
>>>>
>>>> I can post the output of the gspcav1 module with debug=5 for the 
>>>> register writes/reads if that is interesting, or anything else
>>>> for that matter - I'd really like to keep this webcam working and
>>>> staying at kernel 2.6.25 is not an option.
>>>>
>>>> is there a way to get the gspca_zc3xx driver dump register
>>>> read/writes? this would be a quick way to compare the two drivers
>>>> and look at the differences.
>>>>
>>> seems I just found the v4lcompat.so stuff, which (apart from being
>>> a pain in the rear) makes the webcam work again...
>> This seems to be a very common error. IMO, we should write message
>> when loading a gspca that would require libv4l in order to work.
> 
> First, it is strange that mplayer does not work: the v4l2 interface
> seems recognized, but why does it say:
> 
> 	Current format: unknown (0x4745504a)
> 
> while this is JPEG and it knows well how to handle it?
> 
> Then, at probe time, there is:
> 
> 	zc0301: V4L2 driver for ZC0301[P] Image Processor and Control

I pasted too much there, as you can see below I unloaded that driver:

  zc0301: V4L2 driver for ZC0301[P] Image Processor and Control
  Chip v1:1.10 usbcore: registered new interface driver zc0301
  usbcore: deregistering interface driver zc0301


> 
> This means that an other driver wants to handle the webcam. This may
> raise problems.
> 
> Eventually, the v4l library is needed when using any v4l2 driver, not
> only gspca. Hopefully, many popular applications now use it natively,
> as vlc 0.9.x.

interesting, but I can't get vlc to understand either tv:// or 
/dev/video0... any hints?

Auke