b2ac238724
It is common that media drivers call subdev ops in source subdevs, and pass NULL as the state. This was the way to indicate that the callee should use the callee's private active state. E.g.: v4l2_subdev_call(priv->source_sd, pad, get_fmt, NULL, &sd_fmt); Now that we have a real subdev active state in the v4l2_subdev struct, we want the caller to pass a proper state (when available). And furthermore, the state should be locked. This would mean changing all the callers, which is the long term goal. To fix this issue in the short term, let's add an extra wrapper layer to all v4l2_subdev_call_pad_wrappers which deal with states. These wrappers handle the state == NULL case by using the locked active state instead (when available). Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com> Reviewed-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> 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.