xref: /OK3568_Linux_fs/kernel/Documentation/driver-api/media/dtv-core.rst (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun.. SPDX-License-Identifier: GPL-2.0
2*4882a593Smuzhiyun
3*4882a593SmuzhiyunDigital TV (DVB) devices
4*4882a593Smuzhiyun------------------------
5*4882a593Smuzhiyun
6*4882a593SmuzhiyunDigital TV devices are implemented by several different drivers:
7*4882a593Smuzhiyun
8*4882a593Smuzhiyun- A bridge driver that is responsible to talk with the bus where the other
9*4882a593Smuzhiyun  devices are connected (PCI, USB, SPI), bind to the other drivers and
10*4882a593Smuzhiyun  implement the digital demux logic (either in software or in hardware);
11*4882a593Smuzhiyun
12*4882a593Smuzhiyun- Frontend drivers that are usually implemented as two separate drivers:
13*4882a593Smuzhiyun
14*4882a593Smuzhiyun  - A tuner driver that implements the logic which commands the part of
15*4882a593Smuzhiyun    the hardware responsible for tuning into a digital TV transponder or
16*4882a593Smuzhiyun    physical channel. The output of a tuner is usually a baseband or
17*4882a593Smuzhiyun    Intermediate Frequency (IF) signal;
18*4882a593Smuzhiyun
19*4882a593Smuzhiyun  - A demodulator driver (a.k.a "demod") that implements the logic which
20*4882a593Smuzhiyun    commands the digital TV decoding hardware. The output of a demod is
21*4882a593Smuzhiyun    a digital stream, with multiple audio, video and data channels typically
22*4882a593Smuzhiyun    multiplexed using MPEG Transport Stream [#f1]_.
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24*4882a593SmuzhiyunOn most hardware, the frontend drivers talk with the bridge driver using an
25*4882a593SmuzhiyunI2C bus.
26*4882a593Smuzhiyun
27*4882a593Smuzhiyun.. [#f1] Some standards use TCP/IP for multiplexing data, like DVB-H (an
28*4882a593Smuzhiyun   abandoned standard, not used anymore) and ATSC version 3.0 current
29*4882a593Smuzhiyun   proposals. Currently, the DVB subsystem doesn't implement those standards.
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31*4882a593Smuzhiyun
32*4882a593Smuzhiyun.. toctree::
33*4882a593Smuzhiyun    :maxdepth: 1
34*4882a593Smuzhiyun
35*4882a593Smuzhiyun    dtv-common
36*4882a593Smuzhiyun    dtv-frontend
37*4882a593Smuzhiyun    dtv-demux
38*4882a593Smuzhiyun    dtv-ca
39*4882a593Smuzhiyun    dtv-net
40