Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
[sfrench/cifs-2.6.git] / Documentation / media / uapi / dvb / fe-enable-high-lnb-voltage.rst
1 .. -*- coding: utf-8; mode: rst -*-
2
3 .. _FE_ENABLE_HIGH_LNB_VOLTAGE:
4
5 ********************************
6 ioctl FE_ENABLE_HIGH_LNB_VOLTAGE
7 ********************************
8
9 Name
10 ====
11
12 FE_ENABLE_HIGH_LNB_VOLTAGE - Select output DC level between normal LNBf voltages or higher LNBf - voltages.
13
14
15 Synopsis
16 ========
17
18 .. c:function:: int ioctl( int fd, FE_ENABLE_HIGH_LNB_VOLTAGE, unsigned int high )
19     :name: FE_ENABLE_HIGH_LNB_VOLTAGE
20
21
22 Arguments
23 =========
24
25 ``fd``
26     File descriptor returned by :ref:`open() <frontend_f_open>`.
27
28 ``high``
29     Valid flags:
30
31     -  0 - normal 13V and 18V.
32
33     -  >0 - enables slightly higher voltages instead of 13/18V, in order
34        to compensate for long antenna cables.
35
36
37 Description
38 ===========
39
40 Select output DC level between normal LNBf voltages or higher LNBf
41 voltages between 0 (normal) or a value grater than 0 for higher
42 voltages.
43
44
45 Return Value
46 ============
47
48 On success 0 is returned.
49
50 On error -1 is returned, and the ``errno`` variable is set
51 appropriately.
52
53 Generic error codes are described at the
54 :ref:`Generic Error Codes <gen-errors>` chapter.