On 05/03/2015 07:45 PM, Guennadi Liakhovetski wrote:
> Hi Hans,
>
> On Sun, 3 May 2015, Hans Verkuil wrote:
>
>> Hi Guennadi,
>>
>> On 05/03/2015 06:11 PM, Guennadi Liakhovetski wrote:
>>> Hi all,
>>>
>>> Just a quick opinion poll - where and how should the soc-camera framework
>>> and drivers be heading? Possible (probably not all) directions:
>>>
>>> (1) all is good, keep as is. That means keep all drivers, killing them off
>>> only when it becomes very obvious, that noone wants them, keep developing
>>> drivers, that are still being used and updating all of them on any API
>>> updates. Keep me as maintainer, which means slow patch processing rate and
>>> no active participation in new developments - at hardware, soc-camera or
>>> V4L levels.
>>>
>>> (2) we want more! I.e. some contributors are planning to either add new
>>> drivers to it or significantly develop existing ones, see significant
>>> benefit in it. In this case it might become necessary to replace me with
>>> someone, who can be more active in this area.
>>>
>>> (3) slowly phase out. Try to either deprecate and remove soc-camera
>>> drivers one by one or move them out to become independent V4L2 host or
>>> subdevice drivers, but keep updating while still there.
>>>
>>> (4) basically as (3) but even more aggressively - get rid of it ASAP:)
>>>
>>> Opinions? Expecially would be interesting to hear from respective
>>> host-driver maintainers / developers, sorry, not adding CCs, they probably
>>> read the list anyway:)
>>
>> I'm closest to 1. I would certainly not use it for new drivers, I see no
>> reason to do that anymore. The core frameworks are quite good these days
>> and I think the need for soc-camera has basically disappeared. But there
>> is no need to phase out or remove soc-camera drivers (unless they are
>> clearly broken and nobody will fix them). And if someone wants to turn
>> a soc-camera driver into a standalone driver, then I would encourage
>> that.
>
> Understand, thanks.
>
>> However, there are two things that need work fairly soon:
>>
>> 1) the dependency of subdev drivers on soc_camera: that has to go. I plan
>> to work on that, but the first step is to replace the video crop ops by
>> the pad selection ops. I finally got my Renesas sh7724 board up and running,
>
> Uhm... Does anyone really still care about V4L on SuperH?..
I am :-)
It's the only soc-camera board I have, so it's good to have it working.
>
>> so I hope to make progress on this soon. I'll update soc-camera as well
>> to conform to v4l2-compliance. Once that's done I will investigate how to
>> remove the soc-camera dependency.
>>
>> The soc-camera dependency kills the reusability of those drivers and it
>> really needs to be addressed.
>>
>> 2) Converting soc-camera videobuf drivers to vb2. At some point vb1 will be
>> removed, so any remaining vb1 driver will likely be killed off if nobody does
>> the conversion. I believe it is only omap1 and pxa that still use videobuf.
>>
>> I think omap1 might be a candidate for removal, but I don't know about the
>> pxa.
>> Guennadi, what is the status of these drivers?
>
> Dont know, sorry. PXA in general seems to still be quite actively
> maintained - I recently saw a patch series for PXA CCF support, so,
> probably V4L is still in use too.
>
>> If I would do a vb2 conversion
>> for the pxa, would you be able to test it?
>
> I have a board with PXA270, and it still seems to be in the mainline, but
> I don't know how easy it would be to get it running with a current kernel.
Can you take a look? If you can get it running, then I can make a patch for
you to try. But I don't want to put time into that unless I know you can
test it.
I think it is reasonable to phase out the omap1 driver: move it to staging
first and if nobody complains remove it altogether.
Regards,
Hans
--
To unsubscribe from this list: send the line "unsubscribe linux-media" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
