Re: [Linux-uvc-devel] Logitech QuickCam Orbit MP: No such device when reading from /dev/video0

2007-04-02 Thread Laurent Pinchart
Hi Michael,

  The Linux UVC driver doesn't support reading directly from the device
  (yet).  Only the streaming I/O method (using mmap) is supported. You can
  test your webcam with luvcview.

 Thanks for the feedback.  I had tried a few other utilities to read from
 /dev/vide0, but they were giving me errors as well.  I thought that cat(1)
 would be the simplest way to demonstrate the problem, but I guess not :-)

 When I try using the luvcview utility, the error messages I'm seeing are:

   [EMAIL PROTECTED] ~/luvcview-20060920]$ ./luvcview
   uvcview version 0.1.7
   Video driver: x11
   A window manager is available
   video /dev/video0
   Unable to set format: 5.
Init v4L2 failed !! exit fatal

 And in dmesg, I see:

   [17357520.848000] uvcvideo: Trying format 0x47504a4d (MJPG): 320x240.
   [17357520.848000] uvcvideo: Using default frame interval 6.6 us 
 (15.0
 fps). [17357521.148000] uvcvideo: Failed to query (1) UVC control 1 (unit
 0) : -110 (exp. 26).

Welcome to the Logitech hardware bug victims club. You are experiencing a 
know hardware problem for which no proper solution exists yet. A patch has 
been posted some times ago on this list. Depending on how much your computer 
is affected by the bug, it might help you.

 Looking at the luvcview-20060920/v4l2uvc.c file, the codepath that
 generates the Unable to set format error is:

   /* set format in */
   memset(vd-fmt, 0, sizeof(struct v4l2_format));
   vd-fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
   vd-fmt.fmt.pix.width = vd-width;
   vd-fmt.fmt.pix.height = vd-height;
   vd-fmt.fmt.pix.pixelformat = vd-formatIn;
   vd-fmt.fmt.pix.field = V4L2_FIELD_ANY;
   ret = ioctl(vd-fd, VIDIOC_S_FMT, vd-fmt);
   if (ret  0) {
   printf(Unable to set format: %d.\n, errno);
   goto fatal;
   }

 Which I thought that may be an indication that I needed to use the -f
 or -s command line arguments to change the requested format or size to
 something that may be better supported by my camera, so I tried a number
 of different permutations with:

   for f in yuv jpg; do
   for s in 1024x576 1280x960 160x120 176x144 320x240 352x288 432x240 \
480x360 512x288 640x360 640x480 704x576 864x480 960x720; do
   ./luvcview -f $f -s $s -o ~/foo
   done
   done

 However, none of them appeared to be successful.

 Searching around for the Failed to query error message that appeared in
 dmesg seems to suggest that I may be hitting a Logitech hardware bug :-(

Exactly :-( You might be lucky with the so-called reset patch. Please search 
the list archive.

Best regards,

Laurent Pinchart
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Re: [Linux-uvc-devel] Logitech QuickCam Orbit MP: No such device when reading from /dev/video0

2007-04-02 Thread Marcel van Beurden
Laurent Pinchart wrote:
 Welcome to the Logitech hardware bug victims club. You are experiencing a 
 know hardware problem for which no proper solution exists yet. A patch has 
 been posted some times ago on this list. Depending on how much your computer 
 is affected by the bug, it might help you.

I have a Logitech QuickCam Fusion too and it's giving my headaches in Windows 
(I 
didn't jump to Linux yet). I wonder if Logitech is willing to replace webcams 
which have known hardware faults and for which no software fix exists. Does 
anyone have experience with this?

Regards,
Marcel

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Re: [Linux-uvc-devel] Logitech QuickCam Orbit MP: No such device when reading from /dev/video0

2007-04-02 Thread Laurent Pinchart
Hi Marcel,

  Welcome to the Logitech hardware bug victims club. You are experiencing
  a know hardware problem for which no proper solution exists yet. A patch
  has been posted some times ago on this list. Depending on how much your
  computer is affected by the bug, it might help you.

 I have a Logitech QuickCam Fusion too and it's giving my headaches in
 Windows (I didn't jump to Linux yet). I wonder if Logitech is willing to
 replace webcams which have known hardware faults and for which no software
 fix exists. Does anyone have experience with this?

That's interesting. Could you give me more information about the problems you 
experience in Windows ? Please post details about your hardware configuration 
as well (especially processor speed and USB bus controller).

Best regards,

Laurent Pinchart
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