2 files changed, 62 insertions, 0 deletions
diff --git a/Documentation/userspace-api/media/dvb/legacy_dvb_apis.rst b/Documentation/userspace-api/media/dvb/legacy_dvb_apis.rst
index b97d56ee543c..ffe8325749e5 100644
--- a/Documentation/userspace-api/media/dvb/legacy_dvb_apis.rst
+++ b/Documentation/userspace-api/media/dvb/legacy_dvb_apis.rst
@@ -23,3 +23,4 @@ DVB-S2, DVB-T2, ISDB, etc.
     :maxdepth: 1
 
     frontend_legacy_dvbv3_api
+    legacy_dvb_decoder_api
diff --git a/Documentation/userspace-api/media/dvb/legacy_dvb_decoder_api.rst b/Documentation/userspace-api/media/dvb/legacy_dvb_decoder_api.rst
new file mode 100644
index 000000000000..f58985a6e63c
--- /dev/null
+++ b/Documentation/userspace-api/media/dvb/legacy_dvb_decoder_api.rst
@@ -0,0 +1,61 @@
+.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later OR GPL-2.0
+
+.. _legacy_dvb_decoder_api:
+
+============================
+Legacy DVB MPEG Decoder APIs
+============================
+
+.. _legacy_dvb_decoder_notes:
+
+General Notes
+=============
+
+This API has originally been designed for DVB only and is therefore limited to
+the :ref:`legacy_dvb_decoder_formats` used in such digital TV-broadcastsystems.
+
+To circumvent this limitations the more versatile :ref:`V4L2 <v4l2spec>` API has
+been designed. Which replaces this part of the DVB API.
+
+Nevertheless there have been projects build around this API.
+To ensure compatibility this API is kept as it is.
+
+.. attention:: Do **not** use this API in new drivers!
+
+    For audio and video use the :ref:`V4L2 <v4l2spec>` and ALSA APIs.
+
+    Pipelines should be set up using the :ref:`Media Controller  API<media_controller>`.
+
+Practically the decoders seem to be treated differently. The application typically
+knows which decoder is in use or it is specially written for one decoder type.
+Querying capabilities are rarely used because they are already known.
+
+
+.. _legacy_dvb_decoder_formats:
+
+Data Formats
+============
+
+The API has been designed for DVB and compatible broadcastsystems.
+Because of that fact the only supported data formats are ISO/IEC 13818-1
+compatible MPEG streams. The supported payloads may vary depending on the
+used decoder.
+
+Timestamps are always MPEG PTS as defined in ITU T-REC-H.222.0 /
+ISO/IEC 13818-1, if not otherwise noted.
+
+For storing recordings typically TS streams are used, in lesser extent PES.
+Both variants are commonly accepted for playback, but it may be driver dependent.
+
+
+
+
+Table of Contents
+=================
+
+.. toctree::
+    :maxdepth: 2
+
+    legacy_dvb_video
+    legacy_dvb_audio
+    legacy_dvb_osd