On Thu, 1 Sep 2011, Sakari Ailus wrote: > Hi Guennadi, > > On Wed, Aug 31, 2011 at 08:02:42PM +0200, Guennadi Liakhovetski wrote: > > Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@xxxxxx> > > Cc: Hans Verkuil <hverkuil@xxxxxxxxx> > > Cc: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx> > > Cc: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx> > > Cc: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxx> > > Cc: Pawel Osciak <pawel@xxxxxxxxxx> > > Cc: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxxxxxxxxxxxxx> > > --- > > Documentation/DocBook/media/v4l/io.xml | 17 +++ > > Documentation/DocBook/media/v4l/v4l2.xml | 2 + > > .../DocBook/media/v4l/vidioc-create-bufs.xml | 147 ++++++++++++++++++++ > > .../DocBook/media/v4l/vidioc-prepare-buf.xml | 96 +++++++++++++ > > 4 files changed, 262 insertions(+), 0 deletions(-) > > create mode 100644 Documentation/DocBook/media/v4l/vidioc-create-bufs.xml > > create mode 100644 Documentation/DocBook/media/v4l/vidioc-prepare-buf.xml [snip] > > + <refsect1> > > + <title>Description</title> > > + > > + <para>Applications can optionally call the > > +<constant>VIDIOC_PREPARE_BUF</constant> ioctl to pass ownership of the buffer > > +to the driver before actually enqueuing it, using the > > +<constant>VIDIOC_QBUF</constant> ioctl, and to prepare it for future I/O. > > +Such preparations may include cache invalidation or cleaning. Performing them > > I think it could be added that the first time when the buffer is prepared, > the preparation may include very time consuming tasks such as memory > allocation and iommu mapping of that memory. Sure, looking forward to your incremental patch. Thanks Guennadi --- Guennadi Liakhovetski, Ph.D. Freelance Open-Source Software Developer http://www.open-technology.de/ -- 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
