Hi Laurent,
Thanks for getting back to me. I took a look at what you said, and here's what I've found. > What are the symptoms ? Do you get an error when you try to access the > control ? If so, what error (errno) do you get? When I try to access the control, I get errno 22 (EINVAL) returned. I've also noticed that when I enumerate the controls on the camera, my new control displays the same information as a control that is not supported by this camera. This is why I was wondering if I needed to associate the control with the camera somehow. Output from my test app: ID: 0x800000a Exposure, Auto Min: 0 Max: 100 Step: 3 ID: 0x800000b Exposure (Absolute) Min: 100 Max: 10000 Step: 50 ID: 0x800000c Min: 100 Max: 10000 Step: 50 ID: 0x800000d Min: 100 Max: 10000 Step: 50 ID: 0x800000e Min: 100 Max: 10000 Step: 50 The first two controls are supported on this camera. Controls c & d are unsupported, control e is my new control. > If you can enumerate the control on your device instance, there should be > no "association" problem. Try to raise the trace level to 255 (modprobe > uvcvideo trace=255 or echo 255 > /sys/modules/uvcvideo/parameters/trace) > and check the kernel log (dmesg) for error messages after you try to > access the control from your userspace application. So I raised the trace level, and I've been able to pinpoint where the error is occurring. The function uvc_find_ctrl (uvc_ctrl.c) is unable to find the control. The trace message logged in dmesg is "uvcvideo: Control 0x800000e not found. After some more debugging I also found that uvc_find_ctrl searchs the video->iterms list, but not the video->extensions list, presumably because there are no items in this list? Could this be my problem? Thanks, Nathanael _______________________________________________ Linux-uvc-devel mailing list [email protected] https://lists.berlios.de/mailman/listinfo/linux-uvc-devel
