Merge tag 'media/v4.8-4' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media

Pull media documentation updates from Mauro Carvalho Chehab:
 "This patch series does the conversion of all media documentation stuff
  to Restrutured Text markup format and add them to the
  Documentation/index.rst file.

  The media documentation was grouped into 4 books:

    - media uAPI
    - media kAPI
    - V4L driver-specific documentation
    - DVB driver-specific documentation

  It also contains several documentation improvements and one fixup
  patch for a core issue with cropcap.

  PS.  After this patch series, the media DocBook is deprecated and
  should be removed.  I'll add such patch on a future pull request"

* tag 'media/v4.8-4' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (322 commits)
  [media] cx23885-cardlist.rst: add a new card
  [media] doc-rst: add some needed escape codes
  [media] doc-rst: kapi: use :c:func: instead of :cpp:func
  doc-rst: kernel-doc: fix a change introduced by mistake
  [media] v4l2-ioctl.h add debug info for struct v4l2_ioctl_ops
  [media] dvb_ringbuffer.h: some documentation improvements
  [media] v4l2-ctrls.h: fully document the header file
  [media] doc-rst: Fix some typedef ugly warnings
  [media] doc-rst: reorganize the kAPI v4l2 chapters
  [media] rename v4l2-framework.rst to v4l2-intro.rst
  [media] move V4L2 clocks to a separate .rst file
  [media] v4l2-fh.rst: add cross references and markups
  [media] v4l2-fh.rst: add fh contents from v4l2-framework.rst
  [media] v4l2-fh.h: add documentation for it
  [media] v4l2-event.rst: add cross-references and markups
  [media] v4l2-event.h: document all functions
  [media] v4l2-event.rst: add text from v4l2-framework.rst
  [media] v4l2-framework.rst: remove videobuf quick chapter
  [media] v4l2-dev: add cross-references and improve markup
  [media] doc-rst: move v4l2-dev doc to a separate file
  ...

1 files changed, 66 insertions, 0 deletions

diff --git a/Documentation/media/uapi/v4l/vidioc-querystd.rst b/Documentation/media/uapi/v4l/vidioc-querystd.rst
new file mode 100644
index 000000000000..b4a4e222c7b0
--- /dev/null
+++ b/Documentation/media/uapi/v4l/vidioc-querystd.rst
@@ -0,0 +1,66 @@
+.. -*- coding: utf-8; mode: rst -*-
+
+.. _VIDIOC_QUERYSTD:
+
+*********************
+ioctl VIDIOC_QUERYSTD
+*********************
+
+Name
+====
+
+VIDIOC_QUERYSTD - Sense the video standard received by the current input
+
+
+Synopsis
+========
+
+.. cpp:function:: int ioctl( int fd, int request, v4l2_std_id *argp )
+
+
+Arguments
+=========
+
+``fd``
+    File descriptor returned by :ref:`open() <func-open>`.
+
+``request``
+    VIDIOC_QUERYSTD
+
+``argp``
+
+
+Description
+===========
+
+The hardware may be able to detect the current video standard
+automatically. To do so, applications call :ref:`VIDIOC_QUERYSTD` with a
+pointer to a :ref:`v4l2_std_id <v4l2-std-id>` type. The driver
+stores here a set of candidates, this can be a single flag or a set of
+supported standards if for example the hardware can only distinguish
+between 50 and 60 Hz systems. If no signal was detected, then the driver
+will return V4L2_STD_UNKNOWN. When detection is not possible or fails,
+the set must contain all standards supported by the current video input
+or output.
+
+.. note:: Drivers shall *not* switch the video standard
+   automatically if a new video standard is detected. Instead, drivers
+   should send the ``V4L2_EVENT_SOURCE_CHANGE`` event (if they support
+   this) and expect that userspace will take action by calling
+   :ref:`VIDIOC_QUERYSTD`. The reason is that a new video standard can mean
+   different buffer sizes as well, and you cannot change buffer sizes on
+   the fly. In general, applications that receive the Source Change event
+   will have to call :ref:`VIDIOC_QUERYSTD`, and if the detected video
+   standard is valid they will have to stop streaming, set the new
+   standard, allocate new buffers and start streaming again.
+
+
+Return Value
+============
+
+On success 0 is returned, on error -1 and the ``errno`` variable is set
+appropriately. The generic error codes are described at the
+:ref:`Generic Error Codes <gen-errors>` chapter.
+
+ENODATA
+    Standard video timings are not supported for this input or output.