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diff --git a/Documentation/media/uapi/v4l/vidioc-g-modulator.rst b/Documentation/media/uapi/v4l/vidioc-g-modulator.rst deleted file mode 100644 index 2c33a8bdcc47..000000000000 --- a/Documentation/media/uapi/v4l/vidioc-g-modulator.rst +++ /dev/null @@ -1,202 +0,0 @@ -.. 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 - -.. _VIDIOC_G_MODULATOR: - -******************************************** -ioctl VIDIOC_G_MODULATOR, VIDIOC_S_MODULATOR -******************************************** - -Name -==== - -VIDIOC_G_MODULATOR - VIDIOC_S_MODULATOR - Get or set modulator attributes - - -Synopsis -======== - -.. c:function:: int ioctl( int fd, VIDIOC_G_MODULATOR, struct v4l2_modulator *argp ) - :name: VIDIOC_G_MODULATOR - -.. c:function:: int ioctl( int fd, VIDIOC_S_MODULATOR, const struct v4l2_modulator *argp ) - :name: VIDIOC_S_MODULATOR - - -Arguments -========= - -``fd`` - File descriptor returned by :ref:`open() <func-open>`. - -``argp`` - Pointer to struct :c:type:`v4l2_modulator`. - - -Description -=========== - -To query the attributes of a modulator applications initialize the -``index`` field and zero out the ``reserved`` array of a struct -:c:type:`v4l2_modulator` and call the -:ref:`VIDIOC_G_MODULATOR <VIDIOC_G_MODULATOR>` ioctl with a pointer to this structure. Drivers -fill the rest of the structure or return an ``EINVAL`` error code when the -index is out of bounds. To enumerate all modulators applications shall -begin at index zero, incrementing by one until the driver returns -EINVAL. - -Modulators have two writable properties, an audio modulation set and the -radio frequency. To change the modulated audio subprograms, applications -initialize the ``index`` and ``txsubchans`` fields and the ``reserved`` -array and call the :ref:`VIDIOC_S_MODULATOR <VIDIOC_G_MODULATOR>` ioctl. Drivers may choose a -different audio modulation if the request cannot be satisfied. However -this is a write-only ioctl, it does not return the actual audio -modulation selected. - -:ref:`SDR <sdr>` specific modulator types are ``V4L2_TUNER_SDR`` and -``V4L2_TUNER_RF``. For SDR devices ``txsubchans`` field must be -initialized to zero. The term 'modulator' means SDR transmitter in this -context. - -To change the radio frequency the -:ref:`VIDIOC_S_FREQUENCY <VIDIOC_G_FREQUENCY>` ioctl is available. - - -.. tabularcolumns:: |p{2.9cm}|p{2.9cm}|p{5.8cm}|p{2.9cm}|p{3.0cm}| - -.. c:type:: v4l2_modulator - -.. flat-table:: struct v4l2_modulator - :header-rows: 0 - :stub-columns: 0 - :widths: 1 1 2 1 1 - - * - __u32 - - ``index`` - - Identifies the modulator, set by the application. - * - __u8 - - ``name``\ [32] - - Name of the modulator, a NUL-terminated ASCII string. - - This information is intended for the user. - * - __u32 - - ``capability`` - - Modulator capability flags. No flags are defined for this field, - the tuner flags in struct :c:type:`v4l2_tuner` are - used accordingly. The audio flags indicate the ability to encode - audio subprograms. They will *not* change for example with the - current video standard. - * - __u32 - - ``rangelow`` - - The lowest tunable frequency in units of 62.5 KHz, or if the - ``capability`` flag ``V4L2_TUNER_CAP_LOW`` is set, in units of - 62.5 Hz, or if the ``capability`` flag ``V4L2_TUNER_CAP_1HZ`` is - set, in units of 1 Hz. - * - __u32 - - ``rangehigh`` - - The highest tunable frequency in units of 62.5 KHz, or if the - ``capability`` flag ``V4L2_TUNER_CAP_LOW`` is set, in units of - 62.5 Hz, or if the ``capability`` flag ``V4L2_TUNER_CAP_1HZ`` is - set, in units of 1 Hz. - * - __u32 - - ``txsubchans`` - - With this field applications can determine how audio sub-carriers - shall be modulated. It contains a set of flags as defined in - :ref:`modulator-txsubchans`. - - .. note:: - - The tuner ``rxsubchans`` flags are reused, but the - semantics are different. Video output devices - are assumed to have an analog or PCM audio input with 1-3 - channels. The ``txsubchans`` flags select one or more channels - for modulation, together with some audio subprogram indicator, - for example, a stereo pilot tone. - * - __u32 - - ``type`` - - :cspan:`2` Type of the modulator, see :c:type:`v4l2_tuner_type`. - * - __u32 - - ``reserved``\ [3] - - Reserved for future extensions. - - Drivers and applications must set the array to zero. - - - -.. tabularcolumns:: |p{6.6cm}|p{2.2cm}|p{8.7cm}| - -.. _modulator-txsubchans: - -.. flat-table:: Modulator Audio Transmission Flags - :header-rows: 0 - :stub-columns: 0 - :widths: 3 1 4 - - * - ``V4L2_TUNER_SUB_MONO`` - - 0x0001 - - Modulate channel 1 as mono audio, when the input has more - channels, a down-mix of channel 1 and 2. This flag does not - combine with ``V4L2_TUNER_SUB_STEREO`` or - ``V4L2_TUNER_SUB_LANG1``. - * - ``V4L2_TUNER_SUB_STEREO`` - - 0x0002 - - Modulate channel 1 and 2 as left and right channel of a stereo - audio signal. When the input has only one channel or two channels - and ``V4L2_TUNER_SUB_SAP`` is also set, channel 1 is encoded as - left and right channel. This flag does not combine with - ``V4L2_TUNER_SUB_MONO`` or ``V4L2_TUNER_SUB_LANG1``. When the - driver does not support stereo audio it shall fall back to mono. - * - ``V4L2_TUNER_SUB_LANG1`` - - 0x0008 - - Modulate channel 1 and 2 as primary and secondary language of a - bilingual audio signal. When the input has only one channel it is - used for both languages. It is not possible to encode the primary - or secondary language only. This flag does not combine with - ``V4L2_TUNER_SUB_MONO``, ``V4L2_TUNER_SUB_STEREO`` or - ``V4L2_TUNER_SUB_SAP``. If the hardware does not support the - respective audio matrix, or the current video standard does not - permit bilingual audio the :ref:`VIDIOC_S_MODULATOR <VIDIOC_G_MODULATOR>` ioctl shall - return an ``EINVAL`` error code and the driver shall fall back to mono - or stereo mode. - * - ``V4L2_TUNER_SUB_LANG2`` - - 0x0004 - - Same effect as ``V4L2_TUNER_SUB_SAP``. - * - ``V4L2_TUNER_SUB_SAP`` - - 0x0004 - - When combined with ``V4L2_TUNER_SUB_MONO`` the first channel is - encoded as mono audio, the last channel as Second Audio Program. - When the input has only one channel it is used for both audio - tracks. When the input has three channels the mono track is a - down-mix of channel 1 and 2. When combined with - ``V4L2_TUNER_SUB_STEREO`` channel 1 and 2 are encoded as left and - right stereo audio, channel 3 as Second Audio Program. When the - input has only two channels, the first is encoded as left and - right channel and the second as SAP. When the input has only one - channel it is used for all audio tracks. It is not possible to - encode a Second Audio Program only. This flag must combine with - ``V4L2_TUNER_SUB_MONO`` or ``V4L2_TUNER_SUB_STEREO``. If the - hardware does not support the respective audio matrix, or the - current video standard does not permit SAP the - :ref:`VIDIOC_S_MODULATOR <VIDIOC_G_MODULATOR>` ioctl shall return an ``EINVAL`` error code and - driver shall fall back to mono or stereo mode. - * - ``V4L2_TUNER_SUB_RDS`` - - 0x0010 - - Enable the RDS encoder for a radio FM transmitter. - - -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. - -EINVAL - The struct :c:type:`v4l2_modulator` ``index`` is - out of bounds. |