Re: [GIT PATCHES FOR 3.1] s5p-fimc and noon010pc30 driver updates

[Mauro Carvalho Chehab <mchehab@redhat.com>]

Em 10-08-2011 05:41, Sylwester Nawrocki escreveu:
>>>> Why not? I never saw an embedded hardware that allows physically changing the
>>>> sensor.
> 
> I understood Laurent's statement that you can have same ISP driver deployed on
> multiple boards fitted with various sensors. Hence the multiple configurations
> that cannot be known in advance,

True, but such kind of dependence should solved either at config time or at
probe time. It doesn't make any sense to show that a hardware is present, when
it is not. This applies to both V4L or MC APIs (and also to sysfs).

>>>> If V4L2 API is not enough, implementing it on libv4l won't solve, as userspace
>>>> apps will use V4L2 API for requresting it.
>>>
>>> There are two kind of applications: specialised and generic. The generic
>>> ones may rely on restrictive policies put in place by a libv4l plugin
>>> whereas the specialised applications need to access the device's features
>>> directly to get the most out of it.
>>
>> A submitted upstream driver should be capable of working with the existing
>> tools/userspace.
>>
>> Currently, there isn't such libv4l plugins (or, at least, I failed to see a
>> merged plugin there for N9, S5P, etc). Let's not upstream new drivers or remove 
>> functionalities from already existing drivers based on something that has yet 
>> to be developed.
>>
>> After having it there properly working and tested independently, we may consider
>> patches removing V4L2 interfaces that were obsoleted in favor of using the libv4l
>> implementation, of course using the Kernel way of deprecating interfaces. But
>> doing it before having it, doesn't make any sense.
>>
>> Let's not put the the cart before the horse.
> 
> That's a good point. My long term plan was to deprecate and remove duplicated ioctls
> at the driver _once_ support for regular V4L2 interface on top of MC/subdev API
> is added at the v4l2 libraries. But this will happen after I create an initial.. 
> *cough* openmax IL for the driver. Which is not what the Tigers like best..

Ok.
> 
> --
> Regards,
> Sylwester