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diff --git a/Documentation/media/uapi/v4l/tuner.rst b/Documentation/media/uapi/v4l/tuner.rst deleted file mode 100644 index 601dc535199c..000000000000 --- a/Documentation/media/uapi/v4l/tuner.rst +++ /dev/null @@ -1,92 +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 - -.. _tuner: - -********************* -Tuners and Modulators -********************* - - -Tuners -====== - -Video input devices can have one or more tuners demodulating a RF -signal. Each tuner is associated with one or more video inputs, -depending on the number of RF connectors on the tuner. The ``type`` -field of the respective struct :c:type:`v4l2_input` -returned by the :ref:`VIDIOC_ENUMINPUT` ioctl is -set to ``V4L2_INPUT_TYPE_TUNER`` and its ``tuner`` field contains the -index number of the tuner. - -Radio input devices have exactly one tuner with index zero, no video -inputs. - -To query and change tuner properties applications use the -:ref:`VIDIOC_G_TUNER <VIDIOC_G_TUNER>` and -:ref:`VIDIOC_S_TUNER <VIDIOC_G_TUNER>` ioctls, respectively. The -struct :c:type:`v4l2_tuner` returned by :ref:`VIDIOC_G_TUNER <VIDIOC_G_TUNER>` -also contains signal status information applicable when the tuner of the -current video or radio input is queried. - -.. note:: - - :ref:`VIDIOC_S_TUNER <VIDIOC_G_TUNER>` does not switch the - current tuner, when there is more than one. The tuner is solely - determined by the current video input. Drivers must support both ioctls - and set the ``V4L2_CAP_TUNER`` flag in the struct :c:type:`v4l2_capability` - returned by the :ref:`VIDIOC_QUERYCAP` ioctl when the - device has one or more tuners. - - -Modulators -========== - -Video output devices can have one or more modulators, that modulate a -video signal for radiation or connection to the antenna input of a TV -set or video recorder. Each modulator is associated with one or more -video outputs, depending on the number of RF connectors on the -modulator. The ``type`` field of the respective struct -:c:type:`v4l2_output` returned by the -:ref:`VIDIOC_ENUMOUTPUT` ioctl is set to -``V4L2_OUTPUT_TYPE_MODULATOR`` and its ``modulator`` field contains the -index number of the modulator. - -Radio output devices have exactly one modulator with index zero, no -video outputs. - -A video or radio device cannot support both a tuner and a modulator. Two -separate device nodes will have to be used for such hardware, one that -supports the tuner functionality and one that supports the modulator -functionality. The reason is a limitation with the -:ref:`VIDIOC_S_FREQUENCY <VIDIOC_G_FREQUENCY>` ioctl where you -cannot specify whether the frequency is for a tuner or a modulator. - -To query and change modulator properties applications use the -:ref:`VIDIOC_G_MODULATOR <VIDIOC_G_MODULATOR>` and -:ref:`VIDIOC_S_MODULATOR <VIDIOC_G_MODULATOR>` ioctl. Note that -:ref:`VIDIOC_S_MODULATOR <VIDIOC_G_MODULATOR>` does not switch the current modulator, when there -is more than one at all. The modulator is solely determined by the -current video output. Drivers must support both ioctls and set the -``V4L2_CAP_MODULATOR`` flag in the struct -:c:type:`v4l2_capability` returned by the -:ref:`VIDIOC_QUERYCAP` ioctl when the device has -one or more modulators. - - -Radio Frequency -=============== - -To get and set the tuner or modulator radio frequency applications use -the :ref:`VIDIOC_G_FREQUENCY <VIDIOC_G_FREQUENCY>` and -:ref:`VIDIOC_S_FREQUENCY <VIDIOC_G_FREQUENCY>` ioctl which both take -a pointer to a struct :c:type:`v4l2_frequency`. These -ioctls are used for TV and radio devices alike. Drivers must support -both ioctls when the tuner or modulator ioctls are supported, or when -the device is a radio device. |