xref: /OK3568_Linux_fs/kernel/Documentation/userspace-api/media/dvb/frontend.rst (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
2*4882a593Smuzhiyun
3*4882a593Smuzhiyun.. _dvb_frontend:
4*4882a593Smuzhiyun
5*4882a593Smuzhiyun#######################
6*4882a593SmuzhiyunDigital TV Frontend API
7*4882a593Smuzhiyun#######################
8*4882a593Smuzhiyun
9*4882a593SmuzhiyunThe Digital TV frontend API was designed to support three groups of delivery
10*4882a593Smuzhiyunsystems: Terrestrial, cable and Satellite. Currently, the following
11*4882a593Smuzhiyundelivery systems are supported:
12*4882a593Smuzhiyun
13*4882a593Smuzhiyun-  Terrestrial systems: DVB-T, DVB-T2, ATSC, ATSC M/H, ISDB-T, DVB-H,
14*4882a593Smuzhiyun   DTMB, CMMB
15*4882a593Smuzhiyun
16*4882a593Smuzhiyun-  Cable systems: DVB-C Annex A/C, ClearQAM (DVB-C Annex B)
17*4882a593Smuzhiyun
18*4882a593Smuzhiyun-  Satellite systems: DVB-S, DVB-S2, DVB Turbo, ISDB-S, DSS
19*4882a593Smuzhiyun
20*4882a593SmuzhiyunThe Digital TV frontend controls several sub-devices including:
21*4882a593Smuzhiyun
22*4882a593Smuzhiyun-  Tuner
23*4882a593Smuzhiyun
24*4882a593Smuzhiyun-  Digital TV demodulator
25*4882a593Smuzhiyun
26*4882a593Smuzhiyun-  Low noise amplifier (LNA)
27*4882a593Smuzhiyun
28*4882a593Smuzhiyun-  Satellite Equipment Control (SEC) [#f1]_.
29*4882a593Smuzhiyun
30*4882a593SmuzhiyunThe frontend can be accessed through ``/dev/dvb/adapter?/frontend?``.
31*4882a593SmuzhiyunData types and ioctl definitions can be accessed by including
32*4882a593Smuzhiyun``linux/dvb/frontend.h`` in your application.
33*4882a593Smuzhiyun
34*4882a593Smuzhiyun.. note::
35*4882a593Smuzhiyun
36*4882a593Smuzhiyun   Transmission via the internet (DVB-IP) and MMT (MPEG Media Transport)
37*4882a593Smuzhiyun   is not yet handled by this API but a future extension is possible.
38*4882a593Smuzhiyun
39*4882a593Smuzhiyun.. [#f1]
40*4882a593Smuzhiyun
41*4882a593Smuzhiyun   On Satellite systems, the API support for the Satellite Equipment
42*4882a593Smuzhiyun   Control (SEC) allows to power control and to send/receive signals to
43*4882a593Smuzhiyun   control the antenna subsystem, selecting the polarization and choosing
44*4882a593Smuzhiyun   the Intermediate Frequency IF) of the Low Noise Block Converter Feed
45*4882a593Smuzhiyun   Horn (LNBf). It supports the DiSEqC and V-SEC protocols. The DiSEqC
46*4882a593Smuzhiyun   (digital SEC) specification is available at
47*4882a593Smuzhiyun   `Eutelsat <http://www.eutelsat.com/satellites/4_5_5.html>`__.
48*4882a593Smuzhiyun
49*4882a593Smuzhiyun
50*4882a593Smuzhiyun.. toctree::
51*4882a593Smuzhiyun    :maxdepth: 1
52*4882a593Smuzhiyun
53*4882a593Smuzhiyun    query-dvb-frontend-info
54*4882a593Smuzhiyun    dvb-fe-read-status
55*4882a593Smuzhiyun    dvbproperty
56*4882a593Smuzhiyun    frontend_fcalls
57