Re: Cleanup proposal for media/gspca

[Ezequiel <elezegarcia@gmail.com>]

On Sun, Nov 20, 2011 at 08:24:29AM +0100, Jean-Francois Moine wrote:
> 
> Hi Ezequiel,
> 
> It is not a minor patch, but maybe you don't know about object
> programming.
> 
> As it is defined, a gspca device _is_ a video device, as a gspca
> subdriver is a gspca device, and as a video device is a device: each
> lower structure is contained in a higher one.
> 
> Your patch defines the gspca structure as a separate entity which is
> somewhat related to a video device by two reverse pointers. It
> complexifies the structure accesses, adds more code and hides the
> nature of a gspca device.
> 

Hi Jef, 

Thanks for the explanation, I have things much clear now.
I didn't realize linux coding style enforces so explicitly OOP.

I based my patch on tm6000 driver and your
previous mail about the -supposedly- ugly cast:

  gspca_dev = (struct gspca_dev *) video_devdata(file);

Now it doesn't seems so ugly, I guess I went too far.
Still, maybe the 'container_of' trick could make thins
easier to understand.

Thanks again for your patience,
Ezequiel.