Re: [PATCH v1 1/9] media: v4l2-ctrls: Add user controls for StarFive JH7110 ISP

[Changhuang Liang]

Hi Laurent

Thanks for your comments.

On 2023/12/14 19:39, Laurent Pinchart wrote:
> Hi Changhuang,
> 
> Thank you for the patch.
> 
> On Wed, Dec 13, 2023 at 10:50:19PM -0800, Changhuang Liang wrote:
>> Add a control base for StarFive JH7110 ISP driver controls, and reserve
>> 32 controls，also add some controls for StarFive JH7110 ISP.
> 
> ISP parameters should be passed through parameters buffers, not V4L2
> control. See for instance the V4L2_META_FMT_RK_ISP1_PARAMS format in the
> mainline kernel, it describes how to store ISP parameters in a buffer.
> The rkisp1 driver is an example of how this can be implemented.
> 

That means I need to add a video output device before ISP subdev? And 
use queue/dequeue buffer to get the ISP paremeters?

> Please note that the ISP parameters need to be documented precisely,
> regardless of how they're passed by userspace to the kernel. Even with
> V4L2 controls, documentation would be needed. Please see below for
> additional comments.
> 

I will add annotations for this file next version.

>> Signed-off-by: Changhuang Liang <changhuang.liang@xxxxxxxxxxxxxxxx>
>> ---
>>  MAINTAINERS                        |   1 +
>>  include/uapi/linux/jh7110-isp.h    | 342 +++++++++++++++++++++++++++++
>>  include/uapi/linux/v4l2-controls.h |   6 +
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