original_kernel/Documentation/media/kapi/dtv-core.rst

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Digital TV (DVB) devices
------------------------
Digital TV devices are implemented by several different drivers:
- A bridge driver that is responsible to talk with the bus where the other
devices are connected (PCI, USB, SPI), bind to the other drivers and
implement the digital demux logic (either in software or in hardware);
- Frontend drivers that are usually implemented as two separate drivers:
- A tuner driver that implements the logic with commands the part of the
hardware with is reponsible to tune into a digital TV transponder or
physical channel. The output of a tuner is usually a baseband or
Intermediate Frequency (IF) signal;
- A demodulator driver (a.k.a "demod") that implements the logic with
commands the digital TV decoding hardware. The output of a demod is
a digital stream, with multiple audio, video and data channels typically
multiplexed using MPEG Transport Stream [#f1]_.
On most hardware, the frontend drivers talk with the bridge driver using an
I2C bus.
.. [#f1] Some standards use TCP/IP for multiplexing data, like DVB-H (an
abandoned standard, not used anymore) and ATSC version 3.0 current
proposals. Currently, the DVB subsystem doesn't implement those standards.
.. toctree::
:maxdepth: 1
dtv-common
dtv-frontend
dtv-demux
dtv-ca
dtv-net