linux/Documentation/media/uapi/dvb/fe-read-status.rst
Mauro Carvalho Chehab 706f8a9975 [media] doc-rst: improve display of notes and warnings
There are several notes and warning mesages in the middle of
the media docbook. Use the ReST tags for that, as it makes
them visually better and hightlights them.

While here, modify a few ones to make them clearer.

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-07-10 12:06:28 -03:00

136 lines
2.5 KiB
ReStructuredText

.. -*- coding: utf-8; mode: rst -*-
.. _FE_READ_STATUS:
********************
ioctl FE_READ_STATUS
********************
Name
====
FE_READ_STATUS - Returns status information about the front-end. This call only requires - read-only access to the device
Synopsis
========
.. cpp:function:: int ioctl( int fd, int request, unsigned int *status )
Arguments
=========
``fd``
File descriptor returned by :ref:`open() <frontend_f_open>`.
``request``
FE_READ_STATUS
``status``
pointer to a bitmask integer filled with the values defined by enum
:ref:`fe_status <fe-status>`.
Description
===========
All DVB frontend devices support the ``FE_READ_STATUS`` ioctl. It is
used to check about the locking status of the frontend after being
tuned. The ioctl takes a pointer to an integer where the status will be
written.
.. note:: The size of status is actually sizeof(enum fe_status), with
varies according with the architecture. This needs to be fixed in the
future.
.. _fe-status-t:
int fe_status
=============
The fe_status parameter is used to indicate the current state and/or
state changes of the frontend hardware. It is produced using the enum
:ref:`fe_status <fe-status>` values on a bitmask
.. _fe-status:
.. flat-table:: enum fe_status
:header-rows: 1
:stub-columns: 0
- .. row 1
- ID
- Description
- .. row 2
- .. _FE-HAS-SIGNAL:
``FE_HAS_SIGNAL``
- The frontend has found something above the noise level
- .. row 3
- .. _FE-HAS-CARRIER:
``FE_HAS_CARRIER``
- The frontend has found a DVB signal
- .. row 4
- .. _FE-HAS-VITERBI:
``FE_HAS_VITERBI``
- The frontend FEC inner coding (Viterbi, LDPC or other inner code)
is stable
- .. row 5
- .. _FE-HAS-SYNC:
``FE_HAS_SYNC``
- Synchronization bytes was found
- .. row 6
- .. _FE-HAS-LOCK:
``FE_HAS_LOCK``
- The DVB were locked and everything is working
- .. row 7
- .. _FE-TIMEDOUT:
``FE_TIMEDOUT``
- no lock within the last about 2 seconds
- .. row 8
- .. _FE-REINIT:
``FE_REINIT``
- The frontend was reinitialized, application is recommended to
reset DiSEqC, tone and parameters
Return Value
============
On success 0 is returned, on error -1 and the ``errno`` variable is set
appropriately. The generic error codes are described at the
:ref:`Generic Error Codes <gen-errors>` chapter.