[GEM-dev] SOLVED :: V4l2 :: Debugging an issue with cx8800 card.

[B. Bogart]

Should the mode be set to blocking by default and can be changed to
non-blocking via message?

I'm still not sure what the difference is, pros and cons between both modes.

What do you think Johannes?

.b.

Hans-Christoph Steiner wrote:
> 
> Anyway to make this work in a generic way, so it can be included in
> builds that support a wide array of hardware?
> 
> .hc
> 
> On Sep 18, 2008, at 11:47 PM, B. Bogart wrote:
> 
>> Opening the device in blocking mode (removing O_NONBLOCK flag) solves
>> these issues.
>>
>> I'm sending this so that future cx88xx people can fix it:
>>
>> 1. Remove the O_NONBLOCK flag from videoV4L2.cpp
>> 2. make sure your using V4L2 (V4L)
>> 3. make sure you set pix_video to YUV colour: "colorspace YUV" (RGB does
>> not seem to work on my card.)
>>
>> Then it should work as well as the ol bt8x8 cards.
>>
>> .b.
>>
>> B. Bogart wrote:
>>> I have made progress.
>>>
>>> I've managed to get my card working in Gem with some minor changes to
>>> the code. I'm not sure what this code does though, so I'm not sure what
>>> the longer term effect will be.
>>>
>>> I'm sending this to the v4l list as you all are the best to advice on a
>>> proper solution to this issue.
>>>
>>> I've attached the original, and the hacked version.
>>>
>>> Basically the hacked version ignores all errors when running the
>>> following command:
>>>
>>> xioctl (m_tvfd, VIDIOC_DQBUF, &buf)
>>>
>>> What does this command actually do? Why are there two instances in the
>>> capture function?
>>>
>>> I can use the card at 640x480.
>>>
>>> The result is the frame-rate is horrid compared to mplayer (which I
>>> suppose makes sense based on those removed error reports) and also using
>>> the V4L1 w/ a bt8x8 card.
>>>
>>> Does this change give a hint as to what is causing the problem?
>>>
>>> What is the proper way to fix the issue, rather than commenting out
>>> error codes?
>>>
>>> Thanks all,
>>> B. Bogart
>>>
>>>
>>>
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