Re: [PATCH RFC 0/2] pxa_camera transition to v4l2 standalone device

From: Hans Verkuil
Date: Mon Mar 21 2016 - 18:50:03 EST


On 03/21/2016 11:42 PM, Robert Jarzmik wrote:
> Hans Verkuil <hverkuil@xxxxxxxxx> writes:
>
>>> Input ioctls:
>>> test VIDIOC_G/S_TUNER/ENUM_FREQ_BANDS: OK (Not Supported)
>>> test VIDIOC_G/S_FREQUENCY: OK (Not Supported)
>>> test VIDIOC_S_HW_FREQ_SEEK: OK (Not Supported)
>>> test VIDIOC_ENUMAUDIO: OK (Not Supported)
>>> fail: v4l2-test-input-output.cpp(418): G_INPUT not supported for a capture device
>>
>> ENUM/G/S_INPUT is missing and is required for capture devices.
> Okay, that one will be easy I think :) It's a mono-sensor mono-videostream IP.
> I will add that when for RFC v2.
>
>>> Format ioctls:
>>> test VIDIOC_ENUM_FMT/FRAMESIZES/FRAMEINTERVALS: OK
>>> test VIDIOC_G/S_PARM: OK (Not Supported)
>>> test VIDIOC_G_FBUF: OK (Not Supported)
>>> fail: v4l2-test-formats.cpp(329): pixelformat != V4L2_PIX_FMT_JPEG && colorspace == V4L2_COLORSPACE_JPEG
>>> fail: v4l2-test-formats.cpp(432): testColorspace(pix.pixelformat, pix.colorspace, pix.ycbcr_enc, pix.quantization)
>>
>> The sensor should almost certainly use COLORSPACE_SRGB. Certainly not
>> COLORSPACE_JPEG.
> Ah even for YUYV format, I didn't know ...

The pixel format != colorspace. You can read more about that here, if you are
interested:

https://hverkuil.home.xs4all.nl/spec/media.html#colorspaces

>
>>> Buffer ioctls:
>>> test VIDIOC_REQBUFS/CREATE_BUFS/QUERYBUF: OK
>>> fail: v4l2-test-buffers.cpp(571): q.has_expbuf(node)
>>
>> You are missing .vidioc_expbuf = vbs_ioctl_expbuf and the vb2 io_mode
>> VB2_DMABUF.
> Nope, I have :
> .vidioc_expbuf = vb2_ioctl_expbuf,
> vq->io_modes = VB2_MMAP | VB2_DMABUF;
>
> So it's something more subtle, and I have a bit of work to understand what.

Fix the colorspace issue first, I wonder if it is just fallout from that earlier
issue.

Regards,

Hans

>
> Cheers.
>
> --
> Robert
>