[media] doc-rst: media: reordered top sectioning

Within the old section hierarchy, all doc parts has been placed under
the introduction, e.g:

* Linux Media Infrastructure API
    + Introduction
        - Video for Linux API
        - Digital TV API
        - ...

With separating the introduction sibling to the other parts
we get a more common section hierarchy:

* Linux Media Infrastructure API
    + Introduction
    + Video for Linux API
    + Digital TV API
    + ...

BTW: compacting the intro text.

This patch is on top of media_tree/docs-next

Signed-off-by: Markus Heiser <markus.heiser@darmarIT.de>

1 files changed, 46 insertions, 0 deletions

diff --git a/Documentation/media/intro.rst b/Documentation/media/intro.rst
new file mode 100644
index 000000000000..be90bda5b3f3
--- /dev/null
+++ b/Documentation/media/intro.rst
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+.. -*- coding: utf-8; mode: rst -*-
+
+============
+Introduction
+============
+
+This document covers the Linux Kernel to Userspace API's used by video
+and radio streaming devices, including video cameras, analog and digital
+TV receiver cards, AM/FM receiver cards, Software Defined Radio (SDR),
+streaming capture and output devices, codec devices and remote controllers.
+
+A typical media device hardware is shown at :ref:`typical_media_device`.
+
+.. _typical_media_device:
+
+.. figure::  media_api_files/typical_media_device.*
+    :alt:    typical_media_device.svg
+    :align:  center
+
+    Typical Media Device
+
+The media infrastructure API was designed to control such devices. It is
+divided into five parts.
+
+1. The :ref:`first part <v4l2spec>` covers radio, video capture and output,
+   cameras, analog TV devices and codecs.
+
+2. The :ref:`second part <dvbapi>` covers the API used for digital TV and
+   Internet reception via one of the several digital tv standards. While it is
+   called as DVB API, in fact it covers several different video standards
+   including DVB-T/T2, DVB-S/S2, DVB-C, ATSC, ISDB-T, ISDB-S, DTMB, etc. The
+   complete list of supported standards can be found at
+   :ref:`fe-delivery-system-t`.
+
+3. The :ref:`third part <remote_controllers>` covers the Remote Controller API.
+
+4. The :ref:`fourth part <media_controller>` covers the Media Controller API.
+
+5. The :ref:`fifth part <cec>` covers the CEC (Consumer Electronics Control) API.
+
+It should also be noted that a media device may also have audio components, like
+mixers, PCM capture, PCM playback, etc, which are controlled via ALSA API.  For
+additional information and for the latest development code, see:
+`https://linuxtv.org <https://linuxtv.org>`__.  For discussing improvements,
+reporting troubles, sending new drivers, etc, please mail to: `Linux Media
+Mailing List (LMML) <http://vger.kernel.org/vger-lists.html#linux-media>`__.