Re: [Qemu-devel] [RFC PATCH 0/2] Add USB Video Class device emulation.

[Natalia Portillo]

Hi David,

> Attempting to try out your patches, but it's failing with the following:
> 
> usb-uvc: Init called
> usb-uvc: Trying to open /dev/video0
> .usb-uvc: Device opened correctly.
> usb-uvc: Querying capabilities.
> usb-uvc: Device driver: uvcvideo
> usb-uvc: Device name: Laptop_Integrated_Webcam_0.3M
> usb-uvc: Device bus: usb-0000:00:1a.7-6
> usb-uvc: Driver version: 0.1.0
> usb-uvc: Device capabilities: 0x04000001
> usb-uvc: Enumerating video inputs.
> usb-uvc: Setting video input to index 0
> usb-uvc: Video input correctly set.
> usb-uvc: Trying to set 320x240 MJPEG.
> qemu-system-x86_64: -device usb-uvc-webcam,device=/dev/video0: Invalid
> format.

As for now only cameras that allow MJPEG format will work.
Check your camera specifications (lsusb -v works if your real camera is UVC, 
check driver's source otherwise).
Cameras with RAW frames (YUYV and NV12 formats) do not work, yet. I'm on it.

> 
> Also, I tried a PWC camera which is not a V4L2_INPUT_TYPE_CAMERA and
> noticed that video_input_index is used uninitialized in usb_uvc_initfn
It's a webcam?
Could you give me more information?
Manufacturer, model, linux's module name.

All webcams SHOULD (and MUST) implement V4L2_INPUT_TYPE_CAMERA.
Not the same for video cameras or capture devices (PAL/NTSC, DVB/ATSC).

Regards,
Natalia Portillo