Hans Verkuil 10905d70d7 media: media-request: implement media requests
Add initial media request support:

1) Add MEDIA_IOC_REQUEST_ALLOC ioctl support to media-device.c
2) Add struct media_request to store request objects.
3) Add struct media_request_object to represent a request object.
4) Add MEDIA_REQUEST_IOC_QUEUE/REINIT ioctl support.

Basic lifecycle: the application allocates a request, adds
objects to it, queues the request, polls until it is completed
and can then read the final values of the objects at the time
of completion. When it closes the file descriptor the request
memory will be freed (actually, when the last user of that request
releases the request).

Drivers will bind an object to a request (the 'adds objects to it'
phase), when MEDIA_REQUEST_IOC_QUEUE is called the request is
validated (req_validate op), then queued (the req_queue op).

When done with an object it can either be unbound from the request
(e.g. when the driver has finished with a vb2 buffer) or marked as
completed (e.g. for controls associated with a buffer). When all
objects in the request are completed (or unbound), then the request
fd will signal an exception (poll).

Co-developed-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Co-developed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Co-developed-by: Alexandre Courbot <acourbot@chromium.org>

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2018-08-31 11:04:51 -04:00
2018-08-18 15:55:59 -07:00
2018-08-25 13:40:38 -07:00
2018-08-25 18:43:59 -07:00
2018-08-26 11:41:08 -07:00
2018-08-24 13:00:33 -07:00
2018-04-15 17:21:30 -07:00
2018-08-25 18:13:10 -07:00
2017-11-17 17:45:29 -08:00
2018-08-25 18:13:10 -07:00
2018-08-26 14:11:59 -07:00

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.
See Documentation/00-INDEX for a list of what is contained in each file.

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.
Description
Linux kernel source tree
Readme 3.5 GiB
Languages
C 97.7%
Assembly 1.2%
Shell 0.4%
Makefile 0.3%
Python 0.2%
Other 0.1%