1.. Permission is granted to copy, distribute and/or modify this
2.. document under the terms of the GNU Free Documentation License,
3.. Version 1.1 or any later version published by the Free Software
4.. Foundation, with no Invariant Sections, no Front-Cover Texts
5.. and no Back-Cover Texts. A copy of the license is included at
6.. Documentation/userspace-api/media/fdl-appendix.rst.
7..
8.. TODO: replace it to GFDL-1.1-or-later WITH no-invariant-sections
9
10*************
11Frontend type
12*************
13
14For historical reasons, frontend types are named by the type of
15modulation used in transmission. The fontend types are given by
16fe_type_t type, defined as:
17
18
19.. c:type:: fe_type
20
21.. tabularcolumns:: |p{6.6cm}|p{2.2cm}|p{8.7cm}|
22
23.. flat-table:: Frontend types
24    :header-rows:  1
25    :stub-columns: 0
26    :widths:       3 1 4
27
28
29    -  .. row 1
30
31       -  fe_type
32
33       -  Description
34
35       -  :ref:`DTV_DELIVERY_SYSTEM <DTV-DELIVERY-SYSTEM>` equivalent
36	  type
37
38    -  .. row 2
39
40       -  .. _FE-QPSK:
41
42	  ``FE_QPSK``
43
44       -  For DVB-S standard
45
46       -  ``SYS_DVBS``
47
48    -  .. row 3
49
50       -  .. _FE-QAM:
51
52	  ``FE_QAM``
53
54       -  For DVB-C annex A standard
55
56       -  ``SYS_DVBC_ANNEX_A``
57
58    -  .. row 4
59
60       -  .. _FE-OFDM:
61
62	  ``FE_OFDM``
63
64       -  For DVB-T standard
65
66       -  ``SYS_DVBT``
67
68    -  .. row 5
69
70       -  .. _FE-ATSC:
71
72	  ``FE_ATSC``
73
74       -  For ATSC standard (terrestrial) or for DVB-C Annex B (cable) used
75	  in US.
76
77       -  ``SYS_ATSC`` (terrestrial) or ``SYS_DVBC_ANNEX_B`` (cable)
78
79
80Newer formats like DVB-S2, ISDB-T, ISDB-S and DVB-T2 are not described
81at the above, as they're supported via the new
82:ref:`FE_GET_PROPERTY/FE_GET_SET_PROPERTY <FE_GET_PROPERTY>`
83ioctl's, using the :ref:`DTV_DELIVERY_SYSTEM <DTV-DELIVERY-SYSTEM>`
84parameter.
85
86In the old days, struct :c:type:`dvb_frontend_info`
87used to contain ``fe_type_t`` field to indicate the delivery systems,
88filled with either ``FE_QPSK, FE_QAM, FE_OFDM`` or ``FE_ATSC``. While this
89is still filled to keep backward compatibility, the usage of this field
90is deprecated, as it can report just one delivery system, but some
91devices support multiple delivery systems. Please use
92:ref:`DTV_ENUM_DELSYS <DTV-ENUM-DELSYS>` instead.
93
94On devices that support multiple delivery systems, struct
95:c:type:`dvb_frontend_info`::``fe_type_t`` is
96filled with the currently standard, as selected by the last call to
97:ref:`FE_SET_PROPERTY <FE_GET_PROPERTY>` using the
98:ref:`DTV_DELIVERY_SYSTEM <DTV-DELIVERY-SYSTEM>` property.
99