Hi Sakari, Thank you for the patch. On Wed, Mar 13, 2024 at 09:24:41AM +0200, Sakari Ailus wrote: > Add generic serial metadata mbus formats. These formats describe data > width and packing but not the content itself. The reason for specifying > such formats is that the formats as such are fairly device specific but > they are still handled by CSI-2 receiver drivers that should not be aware > of device specific formats. What makes generic metadata formats possible > is that these formats are parsed by software only, after capturing the > data to system memory. > > Also add a definition for "Data unit" to cover what is essentially a pixel > but is not image data. > > Signed-off-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx> > --- > .../userspace-api/media/glossary.rst | 9 + > .../media/v4l/subdev-formats.rst | 258 ++++++++++++++++++ > include/uapi/linux/media-bus-format.h | 9 + > 3 files changed, 276 insertions(+) > > diff --git a/Documentation/userspace-api/media/glossary.rst b/Documentation/userspace-api/media/glossary.rst > index ef0ab601b5bf..7078141894c5 100644 > --- a/Documentation/userspace-api/media/glossary.rst > +++ b/Documentation/userspace-api/media/glossary.rst > @@ -25,6 +25,15 @@ Glossary > > See :ref:`cec`. > > +.. _media-glossary-data-unit: > + > + Data unit > + > + Unit of data transported by a bus. On parallel buses, the data unit > + consists of one or more related samples while on serial buses the data > + unit is logical. If the data unit is image data, it may also be called a > + pixel. I'm pretty sure nobody will be able to understand what this means, but I don't have a better proposal at the moment. > + > Device Driver > Part of the Linux Kernel that implements support for a hardware > component. > diff --git a/Documentation/userspace-api/media/v4l/subdev-formats.rst b/Documentation/userspace-api/media/v4l/subdev-formats.rst > index eb3cd20b0cf2..cbd475f7cae9 100644 > --- a/Documentation/userspace-api/media/v4l/subdev-formats.rst > +++ b/Documentation/userspace-api/media/v4l/subdev-formats.rst > @@ -8306,3 +8306,261 @@ The following table lists the existing metadata formats. > both sides of the link and the bus format is a fixed > metadata format that is not configurable from userspace. > Width and height will be set to 0 for this format. > + > +Generic Serial Metadata Formats > +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ > + > +Generic serial metadata formats are used on serial buses where the actual data > +content is more or less device specific but the data is transmitted and received > +by multiple devices that do not process the data in any way, simply writing > +it to system memory for processing in software at the end of the pipeline. > + > +The more specific variant describing the actual data is used on the internal > +source pad of the originating sub-device. Maybe this paragraph would be best added in the patch that adds the specific metadata formats, you could then mention one of them as an example: The exact format of the data generated by the device is reported on the internal source pad of the originating sub-device, using one of the more specific metadata formats such as MEDIA_BUS_FMT_CCS_EMBEDDED. > + > +"b" in an array cell signifies a byte of data, followed by the number of the bit s/bit$/byte/ > +and finally the bit number in subscript. "X" indicates a padding bit. We use a lower-case x in pixfmt-rgb.rst, I would do the same here. We also use single quotes there, turning "b" and "x" into 'b' and 'x'. Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx> > + > +.. _media-bus-format-generic-meta: > + > +.. cssclass: longtable > + > +.. flat-table:: Generic Serial Metadata Formats > + :header-rows: 2 > + :stub-columns: 0 > + > + * - Identifier > + - Code > + - > + - :cspan:`23` Data organization within bus ``Data unit > + <media-glossary-data-unit>`` > + * - > + - > + - Bit > + - 23 > + - 22 > + - 21 > + - 20 > + - 19 > + - 18 > + - 17 > + - 16 > + - 15 > + - 14 > + - 13 > + - 12 > + - 11 > + - 10 > + - 9 > + - 8 > + - 7 > + - 6 > + - 5 > + - 4 > + - 3 > + - 2 > + - 1 > + - 0 > + * .. _MEDIA-BUS-FMT-META-8: > + > + - MEDIA_BUS_FMT_META_8 > + - 0x8001 > + - > + - > + - > + - > + - > + - > + - > + - > + - > + - > + - > + - > + - > + - > + - > + - > + - > + - b0\ :sub:`7` > + - b0\ :sub:`6` > + - b0\ :sub:`5` > + - b0\ :sub:`4` > + - b0\ :sub:`3` > + - b0\ :sub:`2` > + - b0\ :sub:`1` > + - b0\ :sub:`0` > + * .. _MEDIA-BUS-FMT-META-10: > + > + - MEDIA_BUS_FMT_META_10 > + - 0x8002 > + - > + - > + - > + - > + - > + - > + - > + - > + - > + - > + - > + - > + - > + - > + - > + - b0\ :sub:`7` > + - b0\ :sub:`6` > + - b0\ :sub:`5` > + - b0\ :sub:`4` > + - b0\ :sub:`3` > + - b0\ :sub:`2` > + - b0\ :sub:`1` > + - b0\ :sub:`0` > + - X > + - X > + * .. _MEDIA-BUS-FMT-META-12: > + > + - MEDIA_BUS_FMT_META_12 > + - 0x8003 > + - > + - > + - > + - > + - > + - > + - > + - > + - > + - > + - > + - > + - > + - b0\ :sub:`7` > + - b0\ :sub:`6` > + - b0\ :sub:`5` > + - b0\ :sub:`4` > + - b0\ :sub:`3` > + - b0\ :sub:`2` > + - b0\ :sub:`1` > + - b0\ :sub:`0` > + - X > + - X > + - X > + - X > + * .. _MEDIA-BUS-FMT-META-14: > + > + - MEDIA_BUS_FMT_META_14 > + - 0x8004 > + - > + - > + - > + - > + - > + - > + - > + - > + - > + - > + - > + - b0\ :sub:`7` > + - b0\ :sub:`6` > + - b0\ :sub:`5` > + - b0\ :sub:`4` > + - b0\ :sub:`3` > + - b0\ :sub:`2` > + - b0\ :sub:`1` > + - b0\ :sub:`0` > + - X > + - X > + - X > + - X > + - X > + - X > + * .. _MEDIA-BUS-FMT-META-16: > + > + - MEDIA_BUS_FMT_META_16 > + - 0x8005 > + - > + - > + - > + - > + - > + - > + - > + - > + - > + - b0\ :sub:`7` > + - b0\ :sub:`6` > + - b0\ :sub:`5` > + - b0\ :sub:`4` > + - b0\ :sub:`3` > + - b0\ :sub:`2` > + - b0\ :sub:`1` > + - b0\ :sub:`0` > + - X > + - X > + - X > + - X > + - X > + - X > + - X > + - X > + * .. _MEDIA-BUS-FMT-META-20: > + > + - MEDIA_BUS_FMT_META_20 > + - 0x8006 > + - > + - > + - > + - > + - > + - b0\ :sub:`7` > + - b0\ :sub:`6` > + - b0\ :sub:`5` > + - b0\ :sub:`4` > + - b0\ :sub:`3` > + - b0\ :sub:`2` > + - b0\ :sub:`1` > + - b0\ :sub:`0` > + - X > + - X > + - X > + - X > + - X > + - X > + - X > + - X > + - X > + - X > + - X > + - X > + * .. _MEDIA-BUS-FMT-META-24: > + > + - MEDIA_BUS_FMT_META_24 > + - 0x8007 > + - > + - b0\ :sub:`7` > + - b0\ :sub:`6` > + - b0\ :sub:`5` > + - b0\ :sub:`4` > + - b0\ :sub:`3` > + - b0\ :sub:`2` > + - b0\ :sub:`1` > + - b0\ :sub:`0` > + - X > + - X > + - X > + - X > + - X > + - X > + - X > + - X > + - X > + - X > + - X > + - X > + - X > + - X > + - X > + - X > diff --git a/include/uapi/linux/media-bus-format.h b/include/uapi/linux/media-bus-format.h > index f05f747e444d..d4c1d991014b 100644 > --- a/include/uapi/linux/media-bus-format.h > +++ b/include/uapi/linux/media-bus-format.h > @@ -174,4 +174,13 @@ > */ > #define MEDIA_BUS_FMT_METADATA_FIXED 0x7001 > > +/* Generic line based metadata formats for serial buses. Next is 0x8008. */ > +#define MEDIA_BUS_FMT_META_8 0x8001 > +#define MEDIA_BUS_FMT_META_10 0x8002 > +#define MEDIA_BUS_FMT_META_12 0x8003 > +#define MEDIA_BUS_FMT_META_14 0x8004 > +#define MEDIA_BUS_FMT_META_16 0x8005 > +#define MEDIA_BUS_FMT_META_20 0x8006 > +#define MEDIA_BUS_FMT_META_24 0x8007 > + > #endif /* __LINUX_MEDIA_BUS_FORMAT_H */ -- Regards, Laurent Pinchart
