Re: [PATCH v8 12/13] [media] v4l: Add V4L2_CAP_FENCES to drivers

[Hans Verkuil]

On 03/09/2018 09:49 AM, Gustavo Padovan wrote:
> From: Gustavo Padovan <gustavo.padovan@xxxxxxxxxxxxx>
> 
> Drivers that use videobuf2 are capable of using fences and
> should report that to userspace.
> 
> The coding style is following what each drivers was already
> doing.

I think this can be simplified for most drivers: you can set this
flag in the v4l_querycap function if vdev->queue is not NULL or if
m2m_ctx is set in struct v4l2_fh.

I believe all non-m2m drivers that use vb2 set vdev->queue. But not
all m2m drivers will set m2m_ctx, so that will need to be checked.

In other words, this way you only need to modify m2m drivers that
do not set m2m_ctx.

Regards,

	Hans