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charset=utf-8 Content-Disposition: inline In-Reply-To: Hi Sakari On Tue, Jan 13, 2026 at 11:32:18PM +0200, Sakari Ailus wrote: > Hi Jacopo, > > On Fri, Jun 20, 2025 at 03:24:09PM +0200, Jacopo Mondi wrote: > > Hi Sakari > > > > On Thu, Jun 19, 2025 at 02:57:56PM +0300, Sakari Ailus wrote: > > > Add new metadata layout (V4L2_METADATA_LAYOUT_CCS) for MIPI CCS embedded > > > data. > > > > > > Signed-off-by: Sakari Ailus > > > Reviewed-by: Julien Massot > > > Reviewed-by: Laurent Pinchart > > > --- > > > .../userspace-api/media/v4l/meta-formats.rst | 1 + > > > .../media/v4l/metadata-layouts.rst | 39 +++++++++++++++++++ > > > .../media/v4l/subdev-formats.rst | 5 +++ > > > include/uapi/linux/v4l2-controls.h | 1 + > > > 4 files changed, 46 insertions(+) > > > create mode 100644 Documentation/userspace-api/media/v4l/metadata-layouts.rst > > > > > > diff --git a/Documentation/userspace-api/media/v4l/meta-formats.rst b/Documentation/userspace-api/media/v4l/meta-formats.rst > > > index bb6876cfc271..c9b908d5fbea 100644 > > > --- a/Documentation/userspace-api/media/v4l/meta-formats.rst > > > +++ b/Documentation/userspace-api/media/v4l/meta-formats.rst > > > @@ -15,6 +15,7 @@ These formats are used for the :ref:`metadata` interface only. > > > metafmt-c3-isp > > > metafmt-d4xx > > > metafmt-generic > > > + metadata-layouts > > > metafmt-intel-ipu3 > > > metafmt-pisp-be > > > metafmt-pisp-fe > > > diff --git a/Documentation/userspace-api/media/v4l/metadata-layouts.rst b/Documentation/userspace-api/media/v4l/metadata-layouts.rst > > > new file mode 100644 > > > index 000000000000..5f717d54d1ca > > > --- /dev/null > > > +++ b/Documentation/userspace-api/media/v4l/metadata-layouts.rst > > > @@ -0,0 +1,39 @@ > > > +.. SPDX-License-Identifier: GPL-2.0 OR GFDL-1.1-no-invariants-or-later > > > + > > > +.. _media_metadata_layouts: > > > + > > > +Metadata Layouts > > > +---------------- > > > + > > > +The :ref:`metadata layout control ` > > > +specifies the on-bus layout of the metadata on pads with a :ref:`generic > > > +metadata mbus code ` independently of the bit > > > +depth. > > > > This has been reviewed by 2 people already, so it might be not having > > this clear, but I guess the intention is to say that the metadata > > layout control describes how data on the bus should be interpreted by > > userspace while the generic metadata mbus code only defines the sample > > size ? > > Hmm. This should probably refer to Data Unit instead. > > Do you think that would help? Bit depth doesn't really apply here. > I have a few problems with the text overall, at least as I read it 1) "the metadata layout control specifies the on-bus layout of the metadata on pads with a generic metadata mbus code" This seems to suggest that the control applies on pads with a generic metadata mbus code 2) "specifies the on-bus layout" I understand why you used "on-bus" (because we use generic formats on pads and when the metadata are written to memory, right ?) but I would rather use "exact layout" or simply "data layout" as you've done below ? 3) I don't get what "on pads with a metadata mbus code indepedently of the bit depth". What's independent from the bit depth ? All in all, I guess what I understand is: The :ref:`metadata layout control ` specifies the exact layout of the metadata stream while the a :ref:`generic metadata mbus code ` on the subdevice pads only describe the data unit size. if that's what you meant > > > > I don't really get that from the above paragraph. Feel free to ignore > > if it's me only :) > > -- > Kind regards, > > Sakari Ailus