On Tue, May 19, 2020 at 11:28:48AM +0200, Hans Verkuil wrote: > On 19/05/2020 11:17, Sakari Ailus wrote: > > Hi Hans, > > > > On Tue, May 19, 2020 at 11:05:31AM +0200, Hans Verkuil wrote: > >> On 19/05/2020 10:50, Sakari Ailus wrote: > >>> The media bus codes to be used on serial busses are documented but there > >>> was no reference from CSI-2 documentation. Add that now. > >>> > >>> Signed-off-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx> > >>> --- > >>> Documentation/driver-api/media/csi2.rst | 7 +++++++ > >>> 1 file changed, 7 insertions(+) > >>> > >>> diff --git a/Documentation/driver-api/media/csi2.rst b/Documentation/driver-api/media/csi2.rst > >>> index da8b356389f0..1653a51d2a6e 100644 > >>> --- a/Documentation/driver-api/media/csi2.rst > >>> +++ b/Documentation/driver-api/media/csi2.rst > >>> @@ -10,6 +10,13 @@ the host SoC. It is defined by the `MIPI alliance`_. > >>> > >>> .. _`MIPI alliance`: http://www.mipi.org/ > >>> > >>> +Media bus formats > >>> +----------------- > >>> + > >>> +Always use the media bus pixel code that describes a parallel format that > >>> +transfers a sample on a single clock cycle. See :ref:`v4l2-mbus-format` for more > >> > >> How about: "transfers the pixel data as a single sample in one clock cycle" > > > > The text is from mbus format documentation. Note that this might not be > > pixel data; it may be metadata as well. > > My problem with 'a sample' is that all parallel media bus formats transfer 'a sample' > in a single clock cycle. It is not clearly defined what 'a sample' is. > > Either the text needs to be improved, or an example should be added here as well > since an example clarifies what is meant. > > > > >> > >> Possibly with an example: "So use e.g. MEDIA_BUS_FMT_SBGGR10_1X10 instead of > >> MEDIA_BUS_FMT_SBGGR10_2X8_PADHI_BE." > > > > There's an example in mbus format documentation. I'm fine adding one here, > > too, but the purpose of this bit is to mainly refer to mbus format > > documentation. Mbus format documentation uses MEDIA_BUS_FMT_BGR888_1X24 and > > MEDIA_BUS_FMT_BGR888_3X8 as the example. > > > > Ah, I see. But then the reference to v4l2-mbus-format is confusing, I'd > change that to v4l2-mbus-pixelcode. That's where the example is. Ah, that's a better label indeed. I'll use that. With this, do you prefer having the example here as well? -- Sakari Ailus
