On 01/10/2017 03:41 PM, Laurent Pinchart wrote: > On Tuesday 10 Jan 2017 08:55:16 Vincent ABRIOU wrote: >> On 01/09/2017 05:59 PM, Laurent Pinchart wrote: >>> On Monday 09 Jan 2017 15:49:00 Vincent ABRIOU wrote: >>>> On 01/09/2017 04:37 PM, Laurent Pinchart wrote: >>>>> Hi Vincent, >>>>> >>>>> Thank you for the patch. >>>>> >>>>> On Monday 03 Oct 2016 13:27:16 Vincent Abriou wrote: >>>>>> Allow uvcvideo compatible devices to allocate their output buffers >>>>>> using contiguous DMA buffers. >>>>> >>>>> Why do you need this ? If it's for buffer sharing with a device that >>>>> requires dma-contig, can't you allocate the buffers on the other device >>>>> and import them on the UVC side ? >>>> >>>> Hi Laurent, >>>> >>>> I need this using Gstreamer simple pipeline to connect an usb webcam >>>> (v4l2src) with a display (waylandsink) activating the zero copy path. >>>> >>>> The waylandsink plugin does not have any contiguous memory pool to >>>> allocate contiguous buffer. So it is up to the upstream element, here >>>> v4l2src, to provide such contiguous buffers. >>> >>> Isn't that a gstreamer issue ? >> >> It is not a gstreamer issue. It is the way it has been decided to work. >> Waylandsink accept DMABUF contiguous buffer but it does not have its own >> buffer pool. > > But why do you put the blame on the kernel when you decide to take the wrong > decision in userspace ? :-) > I don't blame the kernel... I improve it :) >>>>>> Add the "allocators" module parameter option to let uvcvideo use the >>>>>> dma-contig instead of vmalloc. >>>>>> >>>>>> Signed-off-by: Vincent Abriou <vincent.abriou@xxxxxx> >>>>>> --- >>>>>> >>>>>> Documentation/media/v4l-drivers/uvcvideo.rst | 12 ++++++++++++ >>>>>> drivers/media/usb/uvc/Kconfig | 2 ++ >>>>>> drivers/media/usb/uvc/uvc_driver.c | 3 ++- >>>>>> drivers/media/usb/uvc/uvc_queue.c | 23 ++++++++++++++++--- >>>>>> drivers/media/usb/uvc/uvcvideo.h | 4 ++-- >>>>>> 5 files changed, 38 insertions(+), 6 deletions(-) >-- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
