[PATCH/RFC 22/32] libcamera: Add CameraSensor implementation for raw V4L2 sensors

[Tomi Valkeinen]

On 13/03/2024 14:49, Naushir Patuck wrote:
> On Wed, 13 Mar 2024 at 12:46, Tomi Valkeinen
> <tomi.valkeinen at ideasonboard.com> wrote:
>>
>> On 13/03/2024 14:20, Naushir Patuck wrote:
>>
>>> ?> +               case MediaBusFormatInfo::Type::Metadata:
>>>> +                       /*
>>>> +                        * Skip metadata streams that are not sensor embedded
>>>> +                        * data. The source stream reports a generic metadata
>>>> +                        * format, check the sink stream for the exact format.
>>>> +                        */
>>>> +                       formats = subdev_->formats(route.sink);
>>>> +                       if (formats.size() != 1)
>>>> +                               continue;
>>>
>>> Should this test be if (!formats.size()) insead?  It might be possible
>>> to have multiple metadata types.
>>
>> The driver in my branch is old and hacky. I should see what Laurent has
>> done with the imx219 in his branch, and possibly just take that one.
>>
>> I think advertising only a single format makes sense here, as the
>> embedded format is defined by the video format.
>>
>>>> +
>>>> +                       if (MediaBusFormatInfo::info(formats.cbegin()->first).type !=
>>>> +                           MediaBusFormatInfo::Type::EmbeddedData)
>>>> +                               continue;
>>>
>>> The IMX219 driver (from Tomi's kernel tree) advertises
>>> MEDIA_BUS_FMT_META_8 / MEDIA_BUS_FMT_META_10 formats for the embedded
>>> data stream, which translates to a type of
>>> MediaBusFormatInfo::Type::Metadata.  Does the driver need updating, or
>>> should this check include MediaBusFormatInfo::Type::Metadata?
>>
>> Laurent's version should also report those same mbus formats. Hmm, oh,
>> but it uses MEDIA_BUS_FMT_CCS_EMBEDDED for the internal pad...
> 
> Can you point to Laurent's tree?  I'll take the driver from there and
> see if these comments are still valid.

https://lore.kernel.org/all/20240301213231.10340-1-laurent.pinchart@ideasonboard.com/

  Tomi