Re: [PATCH] [media] vb2: map dmabuf for planes on driver queue instead of vidioc_qbuf

From: Luis de Bethencourt
Date: Sat Jul 16 2016 - 08:16:09 EST


On 15/07/16 17:26, Javier Martinez Canillas wrote:
> The buffer planes' dma-buf are currently mapped when buffers are queued
> from userspace but it's more appropriate to do the mapping when buffers
> are queued in the driver since that's when the actual DMA operation are
> going to happen.
>
> Suggested-by: Nicolas Dufresne <nicolas.dufresne@xxxxxxxxxxxxx>
> Signed-off-by: Javier Martinez Canillas <javier@xxxxxxxxxxxxxxx>
>
> ---
>
> Hello,
>
> A side effect of this change is that if the dmabuf map fails for some
> reasons (i.e: a driver using the DMA contig memory allocator but CMA
> not being enabled), the fail will no longer happen on VIDIOC_QBUF but
> later (i.e: in VIDIOC_STREAMON).
>
> I don't know if that's an issue though but I think is worth mentioning.
>
> Best regards,
> Javier
>

Just run this path on the ODROID using GStreamer and the vivid driver.
It worked nicely.

Tested-by: Luis de Bethencourt <luisbg@xxxxxxxxxxxxxxx>

Thanks Javier,
Luis