Re: [RFC PATCH v1 0/5] Add Tegra driver for video capture

From: Hans Verkuil
Date: Wed Feb 05 2020 - 02:57:41 EST


On 2/4/20 8:02 PM, Sowjanya Komatineni wrote:
>>>> I also noticed that changing the test pattern while streaming did not seem to have
>>>> any effect until I stop and restart streaming. Is that a limitation of the HW or of
>>>> the driver?
>>> Do you mean changing test pattern mode of different channel while other
>>> channels are streaming?
>> No, from the same channel. E.g. v4l2-ctl --stream-mmap, then do from another
>> console 'v4l2-ctl -c test-pattern=1'.
>>
>> It depends on the hardware whether or not you can change the test pattern
>> while streaming. But it is nice for testing if this is possible.
>
> Test-pattern mode changes during active streaming will not get set as
> test-pattern mode is in CSI and mode is set every time during the start
> of streaming and then VI keeps capturing the frames.
>
> basically its during CSI subdevice stream enable.

OK. Just add a little comment either at the point the control is created or
where the control is set in vi_s_ctrl(). It's just to document that this
will only take effect at the next streamon.

Regards,

Hans