Re: [RFC, libv4l]: Make libv4l2 usable on devices with complex pipeline

[Mauro Carvalho Chehab <mchehab@s-opensource.com>]

Em Mon, 19 Mar 2018 11:23:54 +0100
Pavel Machek <pavel@ucw.cz> escreveu:

> Hi!
> 
> > I really don't want to add functions for this to libv4l2. That's just a
> > quick hack. The real solution is to parse this from a config
> > file. But  
> 
> No, this is not a quick hack. These are functions that will eventually
> be used by the config parser. (Oh and they allow me to use camera on
> complex hardware, but...).
> 
> Hmm, I have mentioned that already. See quoted text below. 
> 
> > that is a lot more work and it is something that needs to be designed
> > properly.
> > 
> > And that requires someone to put in the time and effort...  
> 
> Which is what I'm trying to do. But some cooperation from your side is
> needed, too. I acknowledged some kind of parser is needed. I can
> do that. Are you willing to cooperate?
> 
> But I need your feedback on the parts below. We can bikeshed about the
> parser later.
> 
> Do they look acceptable? Did I hook up right functions in acceptable
> way?
> 
> If so, yes, I can proceed with parser.
> 
> Best regards,
> 							Pavel


Pavel,

I appreciate your efforts of adding support for mc-based devices to
libv4l.

I guess the main poin that Hans is pointing is that we should take
extra care in order to avoid adding new symbols to libv4l ABI/API
without being sure that they'll be needed in long term, as removing
or changing the API is painful for app developers, and keeping it
ABI compatible with apps compiled against previous versions of the
library is very painful for us.

The hole idea is that generic applications shouldn't notice
if the device is using a mc-based device or not.

Regards,
Mauro