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Commit dc9ef7d1 authored by Hans Verkuil's avatar Hans Verkuil Committed by Mauro Carvalho Chehab
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[media] DocBook media: rewrite frontend open/close 

To fix the last xmllint errors the open and close function reference
description was rewritten based on the v4l2 open and close functions.
Signed-off-by: default avatarHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab@osg.samsung.com>
parent 595d041a
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Documentation/DocBook/media/dvb/frontend.xml
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...@@ -59,11 +59,54 @@ specification is available at ...@@ -59,11 +59,54 @@ specification is available at
<section id="frontend_fcalls"> <section id="frontend_fcalls">
<title>Frontend Function Calls</title> <title>Frontend Function Calls</title>
<section id="frontend_f_open"> <refentry id="frontend_f_open">
<title>open()</title> <refmeta>
<para>DESCRIPTION</para> <refentrytitle>open()</refentrytitle>
<informaltable><tgroup cols="1"><tbody><row> &manvol;
<entry align="char"> </refmeta>
<refnamediv>
<refname>fe-open</refname>
<refpurpose>Open a frontend device</refpurpose>
</refnamediv>
<refsynopsisdiv>
<funcsynopsis>
<funcsynopsisinfo>#include &lt;fcntl.h&gt;</funcsynopsisinfo>
<funcprototype>
<funcdef>int <function>open</function></funcdef>
<paramdef>const char *<parameter>device_name</parameter></paramdef>
<paramdef>int <parameter>flags</parameter></paramdef>
</funcprototype>
</funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Arguments</title>
<variablelist>
<varlistentry>
<term><parameter>device_name</parameter></term>
<listitem>
<para>Device to be opened.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>flags</parameter></term>
<listitem>
<para>Open flags. Access mode must be
<constant>O_RDWR</constant>. This is just a technicality, input devices
still support only reading and output devices only writing.</para>
<para>When the <constant>O_NONBLOCK</constant> flag is
given, the read() function will return the &EAGAIN; when no data is available,
otherwise these functions block until data becomes
available. Other flags have no effect.</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Description</title>
<para>This system call opens a named frontend device (/dev/dvb/adapter0/frontend0) <para>This system call opens a named frontend device (/dev/dvb/adapter0/frontend0)
for subsequent use. Usually the first thing to do after a successful open is to for subsequent use. Usually the first thing to do after a successful open is to
find out the frontend type with <link linkend="FE_GET_INFO">FE_GET_INFO</link>.</para> find out the frontend type with <link linkend="FE_GET_INFO">FE_GET_INFO</link>.</para>
...@@ -82,127 +125,121 @@ specification is available at ...@@ -82,127 +125,121 @@ specification is available at
for use in the specified mode. This implies that the corresponding hardware is for use in the specified mode. This implies that the corresponding hardware is
powered up, and that other front-ends may have been powered down to make powered up, and that other front-ends may have been powered down to make
that possible.</para> that possible.</para>
</entry> </refsect1>
</row></tbody></tgroup></informaltable>
<para>SYNOPSIS</para>
<informaltable><tgroup cols="1"><tbody><row><entry
align="char">
<para>int open(const char &#x22C6;deviceName, int flags);</para>
</entry>
</row></tbody></tgroup></informaltable>
<para>PARAMETERS
</para>
<informaltable><tgroup cols="2"><tbody><row><entry
align="char">
<para>const char
*deviceName</para>
</entry><entry
align="char">
<para>Name of specific video device.</para>
</entry>
</row><row><entry
align="char">
<para>int flags</para>
</entry><entry
align="char">
<para>A bit-wise OR of the following flags:</para>
</entry>
</row><row><entry
align="char">
</entry><entry
align="char">
<para>O_RDONLY read-only access</para>
</entry>
</row><row><entry
align="char">
</entry><entry
align="char">
<para>O_RDWR read/write access</para>
</entry>
</row><row><entry
align="char">
</entry><entry
align="char">
<para>O_NONBLOCK open in non-blocking mode</para>
</entry>
</row><row><entry
align="char">
</entry><entry
align="char">
<para>(blocking mode is the default)</para>
</entry>
</row></tbody></tgroup></informaltable>
<para>RETURN VALUE</para>
<informaltable><tgroup cols="2"><tbody><row><entry
align="char">
<para>ENODEV</para>
</entry><entry
align="char">
<para>Device driver not loaded/available.</para>
</entry>
</row><row><entry
align="char">
<para>EINTERNAL</para>
</entry><entry
align="char">
<para>Internal error.</para>
</entry>
</row><row><entry
align="char">
<para>EBUSY</para>
</entry><entry
align="char">
<para>Device or resource busy.</para>
</entry>
</row><row><entry
align="char">
<para>EINVAL</para>
</entry><entry
align="char">
<para>Invalid argument.</para>
</entry>
</row></tbody></tgroup></informaltable>
</section>
<section id="frontend_f_close"> <refsect1>
<title>close()</title> <title>Return Value</title>
<para>DESCRIPTION
</para> <para>On success <function>open</function> returns the new file
<informaltable><tgroup cols="1"><tbody><row><entry descriptor. On error -1 is returned, and the <varname>errno</varname>
align="char"> variable is set appropriately. Possible error codes are:</para>
<variablelist>
<varlistentry>
<term><errorcode>EACCES</errorcode></term>
<listitem>
<para>The caller has no permission to access the
device.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><errorcode>EBUSY</errorcode></term>
<listitem>
<para>The driver does not support multiple opens and the
device is already in use.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><errorcode>ENXIO</errorcode></term>
<listitem>
<para>No device corresponding to this device special file
exists.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><errorcode>ENOMEM</errorcode></term>
<listitem>
<para>Not enough kernel memory was available to complete the
request.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><errorcode>EMFILE</errorcode></term>
<listitem>
<para>The process already has the maximum number of
files open.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><errorcode>ENFILE</errorcode></term>
<listitem>
<para>The limit on the total number of files open on the
system has been reached.</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
</refentry>
<refentry id="frontend_f_close">
<refmeta>
<refentrytitle>close()</refentrytitle>
&manvol;
</refmeta>
<refnamediv>
<refname>fe-close</refname>
<refpurpose>Close a frontend device</refpurpose>
</refnamediv>
<refsynopsisdiv>
<funcsynopsis>
<funcsynopsisinfo>#include &lt;unistd.h&gt;</funcsynopsisinfo>
<funcprototype>
<funcdef>int <function>close</function></funcdef>
<paramdef>int <parameter>fd</parameter></paramdef>
</funcprototype>
</funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Arguments</title>
<variablelist>
<varlistentry>
<term><parameter>fd</parameter></term>
<listitem>
<para>&fd;</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Description</title>
<para>This system call closes a previously opened front-end device. After closing <para>This system call closes a previously opened front-end device. After closing
a front-end device, its corresponding hardware might be powered down a front-end device, its corresponding hardware might be powered down
automatically.</para> automatically.</para>
</entry> </refsect1>
</row></tbody></tgroup></informaltable> <refsect1>
<para>SYNOPSIS <title>Return Value</title>
</para>
<informaltable><tgroup cols="1"><tbody><row><entry <para>The function returns <returnvalue>0</returnvalue> on
align="char"> success, <returnvalue>-1</returnvalue> on failure and the
<para>int close(int fd);</para> <varname>errno</varname> is set appropriately. Possible error
</entry> codes:</para>
</row></tbody></tgroup></informaltable>
<para>PARAMETERS <variablelist>
</para> <varlistentry>
<informaltable><tgroup cols="2"><tbody><row><entry <term><errorcode>EBADF</errorcode></term>
align="char"> <listitem>
<para>int fd</para> <para><parameter>fd</parameter> is not a valid open file
</entry><entry descriptor.</para>
align="char"> </listitem>
<para>File descriptor returned by a previous call to open().</para> </varlistentry>
</entry> </variablelist>
</row></tbody></tgroup></informaltable> </refsect1>
<para>RETURN VALUE</para> </refentry>
<informaltable><tgroup cols="2"><tbody><row><entry
align="char">
<para>EBADF</para>
</entry><entry
align="char">
<para>fd is not a valid open file descriptor.</para>
</entry>
</row></tbody></tgroup></informaltable>
</section>
&sub-fe-get-info; &sub-fe-get-info;
&sub-fe-read-status; &sub-fe-read-status;
......
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