Re: [RFC PATCH v2 4/5] media: videobuf2: Define vb2_buf_type and vb2_memory

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hi Hans,

On Tuesday 11 August 2015 15:59:35 Hans Verkuil wrote:
> On 08/11/15 15:56, Laurent Pinchart wrote:
> > Hijacking this e-mail thread a bit, would it make sense for the new
> > vb2-core to support different memory allocation for different planes ?
> > I'm foreseeing use cases for buffers that bundle image data with
> > meta-data, where image data should be captured to a dma-buf imported
> > buffer, but meta-data doesn't need to be shared. In that case it wouldn't
> > be easy for userspace to find a dma-buf provider for the meta-data
> > buffers in order to import all planes. Being able to use dma-buf import
> > for the image plane(s) and mmap for the meta-data plane would be easier.
> 
> Yes, that would make sense, but I'd postpone that until someone actually
> needs it.

I might need it soon. Looks like my cunning plan to let someone else implement 
it failed ;-)

> The biggest hurdle would be how to adapt the V4L2 API to this, and not the
> actual vb2 core code.

Changes will be needed in both, but I agree that in-kernel changes should be 
less of a hassle.

-- 
Regards,

Laurent Pinchart