[PATCHv10 08/26] v4l: vb2-dma-contig: add support for scatterlist in userptr mode

Pawel Osciak pawel at osciak.com
Fri Oct 26 09:24:50 PDT 2012

Hi Tomasz,

On Wed, Oct 10, 2012 at 7:46 AM, Tomasz Stanislawski
<t.stanislaws at samsung.com> wrote:
> This patch introduces usage of dma_map_sg to map memory behind
> a userspace pointer to a device as dma-contiguous mapping.

Perhaps I'm missing something, but I don't understand the purpose of
this patch. If the device can do DMA SG, why use videobuf2-dma-contig
and not videobuf2-dma-sg? What would be the difference design-wise
between them if this patch is merged?

Best regards,
Pawel Osciak

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