Re: Patches submitted via linux-media ML that are at patchwork.linuxtv.org

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

Hi Sylwester,

On Wednesday 15 August 2012 18:13:19 Sylwester Nawrocki wrote:
> On 08/15/2012 12:06 AM, Laurent Pinchart wrote:
> > On Tuesday 14 August 2012 18:37:23 Sylwester Nawrocki wrote:
> >> On 08/14/2012 03:04 PM, Mauro Carvalho Chehab wrote:
> >>> This one requires more testing:
> >>> 
> >>> May,15 2012: [GIT,PULL,FOR,3.5] DMABUF importer feature in V4L2 API
> >>>           http://patchwork.linuxtv.org/patch/11268  Sylwester Nawrocki
> >>> <s.nawrocki@samsung.com>
> >> 
> >> Hmm, this is not valid any more. Tomasz just posted a new patch series
> >> that adds DMABUF importer and exporter feature altogether.
> >> 
> >> [PATCHv8 00/26] Integration of videobuf2 with DMABUF
> >> 
> >> I guess we need someone else to submit test patches for other H/W than
> >> just Samsung SoCs. I'm not sure if we've got enough resources to port
> >> this to other hardware. We have been using these features internally for
> >> some time already. It's been 2 kernel releases and I can see only Ack
> >> tags from Laurent on Tomasz's patch series, hence it seems there is no
> >> wide interest in DMABUF support in V4L2 and this patch series is probably
> >> going to stay in a fridge for another few kernel releases.
> > 
> > What would be required to push it to v3.7 ?
> 
> Mauro requested more test coverage on that, which is understood since this
> is a fairly important API enhancement and the V4L2 video overlay API
> replacement.
> 
> We need DMABUF support added at some webcam driver and a DRM driver with
> prime support (or some V4L2 output driver), I guess it would be best to
> have that in a PC environment. It looks like i915/radeon/nouveau drivers
> already have prime support.

uvcvideo has recently been moved to videobuf2, using vb2_vmalloc. I can easily 
test that, except that I have no idea how to export buffers on the i915 side 
when X is running. Have you looked into that ?

> The DRM driver could be an exporter of buffers that would be passed to the
> webcam driver.
> 
> And except the kernel patches we would need a test application, similar
> to that one:
> http://git.infradead.org/users/kmpark/public-apps/blob/a7e755629a74a7ac13788
> 2032a0f7b2480fa1490:/v4l2-drm-example/dmabuf-sharing.c
> 
> I haven't been closely following the DMABUF APIs development, I think
> Tomasz could provide more details on that.
> 
> It's likely I'll get around and prepare a test case as outlined above in
> coming days. Anyway, it would be appreciated if someone else could give this
> patch series a try.

I've previously tested the patches on Renesas hardware, exporting buffers on 
the FBDEV side and importing them on the V4L2 side. We thus have test results 
for two different platforms, albeit all ARM-based.

-- 
Regards,

Laurent Pinchart