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.. Permission is granted to copy, distribute and/or modify this
.. document under the terms of the GNU Free Documentation License,
.. Version 1.1 or any later version published by the Free Software
.. Foundation, with no Invariant Sections, no Front-Cover Texts
.. and no Back-Cover Texts. A copy of the license is included at
.. Documentation/media/uapi/fdl-appendix.rst.
..
.. TODO: replace it to GFDL-1.1-or-later WITH no-invariant-sections

.. _media-controller-types:

Types and flags used to represent the media graph elements
==========================================================

..  tabularcolumns:: |p{8.2cm}|p{10.3cm}|

.. _media-entity-functions:
.. _MEDIA-ENT-F-UNKNOWN:
.. _MEDIA-ENT-F-V4L2-SUBDEV-UNKNOWN:
.. _MEDIA-ENT-F-IO-V4L:
.. _MEDIA-ENT-F-IO-VBI:
.. _MEDIA-ENT-F-IO-SWRADIO:
.. _MEDIA-ENT-F-IO-DTV:
.. _MEDIA-ENT-F-DTV-DEMOD:
.. _MEDIA-ENT-F-TS-DEMUX:
.. _MEDIA-ENT-F-DTV-CA:
.. _MEDIA-ENT-F-DTV-NET-DECAP:
.. _MEDIA-ENT-F-CONN-RF:
.. _MEDIA-ENT-F-CONN-SVIDEO:
.. _MEDIA-ENT-F-CONN-COMPOSITE:
.. _MEDIA-ENT-F-CAM-SENSOR:
.. _MEDIA-ENT-F-FLASH:
.. _MEDIA-ENT-F-LENS:
.. _MEDIA-ENT-F-ATV-DECODER:
.. _MEDIA-ENT-F-TUNER:
.. _MEDIA-ENT-F-IF-VID-DECODER:
.. _MEDIA-ENT-F-IF-AUD-DECODER:
.. _MEDIA-ENT-F-AUDIO-CAPTURE:
.. _MEDIA-ENT-F-AUDIO-PLAYBACK:
.. _MEDIA-ENT-F-AUDIO-MIXER:
.. _MEDIA-ENT-F-PROC-VIDEO-COMPOSER:
.. _MEDIA-ENT-F-PROC-VIDEO-PIXEL-FORMATTER:
.. _MEDIA-ENT-F-PROC-VIDEO-PIXEL-ENC-CONV:
.. _MEDIA-ENT-F-PROC-VIDEO-LUT:
.. _MEDIA-ENT-F-PROC-VIDEO-SCALER:
.. _MEDIA-ENT-F-PROC-VIDEO-STATISTICS:
.. _MEDIA-ENT-F-PROC-VIDEO-ENCODER:
.. _MEDIA-ENT-F-PROC-VIDEO-DECODER:
.. _MEDIA-ENT-F-VID-MUX:
.. _MEDIA-ENT-F-VID-IF-BRIDGE:
.. _MEDIA-ENT-F-DV-DECODER:
.. _MEDIA-ENT-F-DV-ENCODER:

.. cssclass:: longtable

.. flat-table:: Media entity functions
    :header-rows:  0
    :stub-columns: 0

    *  -  ``MEDIA_ENT_F_UNKNOWN`` and
	  ``MEDIA_ENT_F_V4L2_SUBDEV_UNKNOWN``
       -  Unknown entity. That generally indicates that a driver didn't
	  initialize properly the entity, which is a Kernel bug

    *  -  ``MEDIA_ENT_F_IO_V4L``
       -  Data streaming input and/or output entity.

    *  -  ``MEDIA_ENT_F_IO_VBI``
       -  V4L VBI streaming input or output entity

    *  -  ``MEDIA_ENT_F_IO_SWRADIO``
       -  V4L Software Digital Radio (SDR) streaming input or output entity

    *  -  ``MEDIA_ENT_F_IO_DTV``
       -  DVB Digital TV streaming input or output entity

    *  -  ``MEDIA_ENT_F_DTV_DEMOD``
       -  Digital TV demodulator entity.

    *  -  ``MEDIA_ENT_F_TS_DEMUX``
       -  MPEG Transport stream demux entity. Could be implemented on
	  hardware or in Kernelspace by the Linux DVB subsystem.

    *  -  ``MEDIA_ENT_F_DTV_CA``
       -  Digital TV Conditional Access module (CAM) entity

    *  -  ``MEDIA_ENT_F_DTV_NET_DECAP``
       -  Digital TV network ULE/MLE desencapsulation entity. Could be
	  implemented on hardware or in Kernelspace

    *  -  ``MEDIA_ENT_F_CONN_RF``
       -  Connector for a Radio Frequency (RF) signal.

    *  -  ``MEDIA_ENT_F_CONN_SVIDEO``
       -  Connector for a S-Video signal.

    *  -  ``MEDIA_ENT_F_CONN_COMPOSITE``
       -  Connector for a RGB composite signal.

    *  -  ``MEDIA_ENT_F_CAM_SENSOR``
       -  Camera video sensor entity.

    *  -  ``MEDIA_ENT_F_FLASH``
       -  Flash controller entity.

    *  -  ``MEDIA_ENT_F_LENS``
       -  Lens controller entity.

    *  -  ``MEDIA_ENT_F_ATV_DECODER``
       -  Analog video decoder, the basic function of the video decoder is
	  to accept analogue video from a wide variety of sources such as
	  broadcast, DVD players, cameras and video cassette recorders, in
	  either NTSC, PAL, SECAM or HD format, separating the stream into
	  its component parts, luminance and chrominance, and output it in
	  some digital video standard, with appropriate timing signals.

    *  -  ``MEDIA_ENT_F_TUNER``
       -  Digital TV, analog TV, radio and/or software radio tuner, with
	  consists on a PLL tuning stage that converts radio frequency (RF)
	  signal into an Intermediate Frequency (IF). Modern tuners have
	  internally IF-PLL decoders for audio and video, but older models
	  have those stages implemented on separate entities.

    *  -  ``MEDIA_ENT_F_IF_VID_DECODER``
       -  IF-PLL video decoder. It receives the IF from a PLL and decodes
	  the analog TV video signal. This is commonly found on some very
	  old analog tuners, like Philips MK3 designs. They all contain a
	  tda9887 (or some software compatible similar chip, like tda9885).
	  Those devices use a different I2C address than the tuner PLL.

    *  -  ``MEDIA_ENT_F_IF_AUD_DECODER``
       -  IF-PLL sound decoder. It receives the IF from a PLL and decodes
	  the analog TV audio signal. This is commonly found on some very
	  old analog hardware, like Micronas msp3400, Philips tda9840,
	  tda985x, etc. Those devices use a different I2C address than the
	  tuner PLL and should be controlled together with the IF-PLL video
	  decoder.

    *  -  ``MEDIA_ENT_F_AUDIO_CAPTURE``
       -  Audio Capture Function Entity.

    *  -  ``MEDIA_ENT_F_AUDIO_PLAYBACK``
       -  Audio Playback Function Entity.

    *  -  ``MEDIA_ENT_F_AUDIO_MIXER``
       -  Audio Mixer Function Entity.

    *  -  ``MEDIA_ENT_F_PROC_VIDEO_COMPOSER``
       -  Video composer (blender). An entity capable of video
	  composing must have at least two sink pads and one source
	  pad, and composes input video frames onto output video
	  frames. Composition can be performed using alpha blending,
	  color keying, raster operations (ROP), stitching or any other
	  means.

    *  -  ``MEDIA_ENT_F_PROC_VIDEO_PIXEL_FORMATTER``
       -  Video pixel formatter. An entity capable of pixel formatting
	  must have at least one sink pad and one source pad. Read
	  pixel formatters read pixels from memory and perform a subset
	  of unpacking, cropping, color keying, alpha multiplication
	  and pixel encoding conversion. Write pixel formatters perform
	  a subset of dithering, pixel encoding conversion and packing
	  and write pixels to memory.

    *  -  ``MEDIA_ENT_F_PROC_VIDEO_PIXEL_ENC_CONV``
       -  Video pixel encoding converter. An entity capable of pixel
	  encoding conversion must have at least one sink pad and one
	  source pad, and convert the encoding of pixels received on
	  its sink pad(s) to a different encoding output on its source
	  pad(s). Pixel encoding conversion includes but isn't limited
	  to RGB to/from HSV, RGB to/from YUV and CFA (Bayer) to RGB
	  conversions.

    *  -  ``MEDIA_ENT_F_PROC_VIDEO_LUT``
       -  Video look-up table. An entity capable of video lookup table
	  processing must have one sink pad and one source pad. It uses
	  the values of the pixels received on its sink pad to look up
	  entries in internal tables and output them on its source pad.
	  The lookup processing can be performed on all components
	  separately or combine them for multi-dimensional table
	  lookups.

    *  -  ``MEDIA_ENT_F_PROC_VIDEO_SCALER``
       -  Video scaler. An entity capable of video scaling must have
	  at least one sink pad and one source pad, and scale the
	  video frame(s) received on its sink pad(s) to a different
	  resolution output on its source pad(s). The range of
	  supported scaling ratios is entity-specific and can differ
	  between the horizontal and vertical directions (in particular
	  scaling can be supported in one direction only). Binning and
	  sub-sampling (occasionally also referred to as skipping) are
	  considered as scaling.

    *  -  ``MEDIA_ENT_F_PROC_VIDEO_STATISTICS``
       -  Video statistics computation (histogram, 3A, etc.). An entity
	  capable of statistics computation must have one sink pad and
	  one source pad. It computes statistics over the frames
	  received on its sink pad and outputs the statistics data on
	  its source pad.

    *  -  ``MEDIA_ENT_F_PROC_VIDEO_ENCODER``
       -  Video (MPEG, HEVC, VPx, etc.) encoder. An entity capable of
          compressing video frames. Must have one sink pad and at least
	  one source pad.

    *  -  ``MEDIA_ENT_F_PROC_VIDEO_DECODER``
       -  Video (MPEG, HEVC, VPx, etc.) decoder. An entity capable of
          decompressing a compressed video stream into uncompressed video
	  frames. Must have one sink pad and at least one source pad.

    *  -  ``MEDIA_ENT_F_VID_MUX``
       - Video multiplexer. An entity capable of multiplexing must have at
         least two sink pads and one source pad, and must pass the video
         frame(s) received from the active sink pad to the source pad.

    *  -  ``MEDIA_ENT_F_VID_IF_BRIDGE``
       - Video interface bridge. A video interface bridge entity must have at
         least one sink pad and at least one source pad. It receives video
         frames on its sink pad from an input video bus of one type (HDMI, eDP,
         MIPI CSI-2, etc.), and outputs them on its source pad to an output
         video bus of another type (eDP, MIPI CSI-2, parallel, etc.).

    *  -  ``MEDIA_ENT_F_DV_DECODER``
       -  Digital video decoder. The basic function of the video decoder is
	  to accept digital video from a wide variety of sources
	  and output it in some digital video standard, with appropriate
	  timing signals.

    *  -  ``MEDIA_ENT_F_DV_ENCODER``
       -  Digital video encoder. The basic function of the video encoder is
	  to accept digital video from some digital video standard with
	  appropriate timing signals (usually a parallel video bus with sync
	  signals) and output this to a digital video output connector such
	  as HDMI or DisplayPort.

..  tabularcolumns:: |p{5.5cm}|p{12.0cm}|

.. _media-entity-flag:
.. _MEDIA-ENT-FL-DEFAULT:
.. _MEDIA-ENT-FL-CONNECTOR:

.. flat-table:: Media entity flags
    :header-rows:  0
    :stub-columns: 0

    *  -  ``MEDIA_ENT_FL_DEFAULT``
       -  Default entity for its type. Used to discover the default audio,
	  VBI and video devices, the default camera sensor, etc.

    *  -  ``MEDIA_ENT_FL_CONNECTOR``
       -  The entity represents a connector.


..  tabularcolumns:: |p{6.5cm}|p{6.0cm}|p{5.0cm}|

.. _media-intf-type:
.. _MEDIA-INTF-T-DVB-FE:
.. _MEDIA-INTF-T-DVB-DEMUX:
.. _MEDIA-INTF-T-DVB-DVR:
.. _MEDIA-INTF-T-DVB-CA:
.. _MEDIA-INTF-T-DVB-NET:
.. _MEDIA-INTF-T-V4L-VIDEO:
.. _MEDIA-INTF-T-V4L-VBI:
.. _MEDIA-INTF-T-V4L-RADIO:
.. _MEDIA-INTF-T-V4L-SUBDEV:
.. _MEDIA-INTF-T-V4L-SWRADIO:
.. _MEDIA-INTF-T-V4L-TOUCH:
.. _MEDIA-INTF-T-ALSA-PCM-CAPTURE:
.. _MEDIA-INTF-T-ALSA-PCM-PLAYBACK:
.. _MEDIA-INTF-T-ALSA-CONTROL:
.. _MEDIA-INTF-T-ALSA-COMPRESS:
.. _MEDIA-INTF-T-ALSA-RAWMIDI:
.. _MEDIA-INTF-T-ALSA-HWDEP:
.. _MEDIA-INTF-T-ALSA-SEQUENCER:
.. _MEDIA-INTF-T-ALSA-TIMER:

.. flat-table:: Media interface types
    :header-rows:  0
    :stub-columns: 0

    *  -  ``MEDIA_INTF_T_DVB_FE``
       -  Device node interface for the Digital TV frontend
       -  typically, /dev/dvb/adapter?/frontend?

    *  -  ``MEDIA_INTF_T_DVB_DEMUX``
       -  Device node interface for the Digital TV demux
       -  typically, /dev/dvb/adapter?/demux?

    *  -  ``MEDIA_INTF_T_DVB_DVR``
       -  Device node interface for the Digital TV DVR
       -  typically, /dev/dvb/adapter?/dvr?

    *  -  ``MEDIA_INTF_T_DVB_CA``
       -  Device node interface for the Digital TV Conditional Access
       -  typically, /dev/dvb/adapter?/ca?

    *  -  ``MEDIA_INTF_T_DVB_NET``
       -  Device node interface for the Digital TV network control
       -  typically, /dev/dvb/adapter?/net?

    *  -  ``MEDIA_INTF_T_V4L_VIDEO``
       -  Device node interface for video (V4L)
       -  typically, /dev/video?

    *  -  ``MEDIA_INTF_T_V4L_VBI``
       -  Device node interface for VBI (V4L)
       -  typically, /dev/vbi?

    *  -  ``MEDIA_INTF_T_V4L_RADIO``
       -  Device node interface for radio (V4L)
       -  typically, /dev/radio?

    *  -  ``MEDIA_INTF_T_V4L_SUBDEV``
       -  Device node interface for a V4L subdevice
       -  typically, /dev/v4l-subdev?

    *  -  ``MEDIA_INTF_T_V4L_SWRADIO``
       -  Device node interface for Software Defined Radio (V4L)
       -  typically, /dev/swradio?

    *  -  ``MEDIA_INTF_T_V4L_TOUCH``
       -  Device node interface for Touch device (V4L)
       -  typically, /dev/v4l-touch?

    *  -  ``MEDIA_INTF_T_ALSA_PCM_CAPTURE``
       -  Device node interface for ALSA PCM Capture
       -  typically, /dev/snd/pcmC?D?c

    *  -  ``MEDIA_INTF_T_ALSA_PCM_PLAYBACK``
       -  Device node interface for ALSA PCM Playback
       -  typically, /dev/snd/pcmC?D?p

    *  -  ``MEDIA_INTF_T_ALSA_CONTROL``
       -  Device node interface for ALSA Control
       -  typically, /dev/snd/controlC?

    *  -  ``MEDIA_INTF_T_ALSA_COMPRESS``
       -  Device node interface for ALSA Compress
       -  typically, /dev/snd/compr?

    *  -  ``MEDIA_INTF_T_ALSA_RAWMIDI``
       -  Device node interface for ALSA Raw MIDI
       -  typically, /dev/snd/midi?

    *  -  ``MEDIA_INTF_T_ALSA_HWDEP``
       -  Device node interface for ALSA Hardware Dependent
       -  typically, /dev/snd/hwC?D?

    *  -  ``MEDIA_INTF_T_ALSA_SEQUENCER``
       -  Device node interface for ALSA Sequencer
       -  typically, /dev/snd/seq

    *  -  ``MEDIA_INTF_T_ALSA_TIMER``
       -  Device node interface for ALSA Timer
       -  typically, /dev/snd/timer


.. tabularcolumns:: |p{5.5cm}|p{12.0cm}|

.. _media-pad-flag:
.. _MEDIA-PAD-FL-SINK:
.. _MEDIA-PAD-FL-SOURCE:
.. _MEDIA-PAD-FL-MUST-CONNECT:

.. flat-table:: Media pad flags
    :header-rows:  0
    :stub-columns: 0

    *  -  ``MEDIA_PAD_FL_SINK``
       -  Input pad, relative to the entity. Input pads sink data and are
	  targets of links.

    *  -  ``MEDIA_PAD_FL_SOURCE``
       -  Output pad, relative to the entity. Output pads source data and
	  are origins of links.

    *  -  ``MEDIA_PAD_FL_MUST_CONNECT``
       -  If this flag is set and the pad is linked to any other pad, then
	  at least one of those links must be enabled for the entity to be
	  able to stream. There could be temporary reasons (e.g. device
	  configuration dependent) for the pad to need enabled links even
	  when this flag isn't set; the absence of the flag doesn't imply
	  there is none.


One and only one of ``MEDIA_PAD_FL_SINK`` and ``MEDIA_PAD_FL_SOURCE``
must be set for every pad.

.. tabularcolumns:: |p{5.5cm}|p{12.0cm}|

.. _media-link-flag:
.. _MEDIA-LNK-FL-ENABLED:
.. _MEDIA-LNK-FL-IMMUTABLE:
.. _MEDIA-LNK-FL-DYNAMIC:
.. _MEDIA-LNK-FL-LINK-TYPE:

.. flat-table:: Media link flags
    :header-rows:  0
    :stub-columns: 0

    *  -  ``MEDIA_LNK_FL_ENABLED``
       -  The link is enabled and can be used to transfer media data. When
	  two or more links target a sink pad, only one of them can be
	  enabled at a time.

    *  -  ``MEDIA_LNK_FL_IMMUTABLE``
       -  The link enabled state can't be modified at runtime. An immutable
	  link is always enabled.

    *  -  ``MEDIA_LNK_FL_DYNAMIC``
       -  The link enabled state can be modified during streaming. This flag
	  is set by drivers and is read-only for applications.

    *  -  ``MEDIA_LNK_FL_LINK_TYPE``
       -  This is a bitmask that defines the type of the link. Currently,
	  two types of links are supported:

	  .. _MEDIA-LNK-FL-DATA-LINK:

	  ``MEDIA_LNK_FL_DATA_LINK`` if the link is between two pads

	  .. _MEDIA-LNK-FL-INTERFACE-LINK:

	  ``MEDIA_LNK_FL_INTERFACE_LINK`` if the link is between an
	  interface and an entity