ebdb28a55d
The userspace needs a way to match received metadata buffers to pixel data buffers. The obvious way to do this is to use the CSI-2 frame number, as both the metadata and the pixel data have the same frame number as they come from the same frame. However, we don't have means to convey the frame number to userspace. We do have the 'sequence' field, which with a few tricks can be used for this purpose. To achieve this, track the frame number for each virtual channel and increase the sequence for each virtual channel by frame-number - previous-frame-number, also taking into account the eventual wrap of the CSI-2 frame number. If the CSI-2 peripheral does not support frame numbers, CAL increases the frame number register by one each frame. This way we get a monotonically increasing sequence number which is common to all streams using the same virtual channel. Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com> Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.