[Query][soc_camera] How to handle hosts w/color conversion built in?

[Sergio Aguirre <saaguirre@ti.com>]

Hi Guennadi and all,

I've been trying to make my omap4 camera host driver to allow YUYV -> 
NV12 color conversion, and add that to the supported host-client 
formats, but I think I have hit the wall with the host design.

I noticed that the soc_camera seems to be designed to just pass-through 
the client supported formats (i.e. if my sensor supports YUYV and JPEG, 
those will be the supported formats only)

Now, in my host driver, I have a feature to do a color conversion to 
NV12, but I'm still not sure on how to expand the supported formats to, 
say: YUYV, JPEG, and NV12 (which would be available only if the client 
outputs YUYV, of course).

I was trying adding a customized get_formats function, but as 
soc_camera_init_user_formats anyways depends heavly on the sensor's 
enum_mbus_fmt, it's hard to add supported formats that the sensor 
doesn't directly support.

Has this been done before? Any advice?

Regards,
Sergio