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Diffstat (limited to 'Documentation/DocBook/media/v4l/cec-func-open.xml')
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diff --git a/Documentation/DocBook/media/v4l/cec-func-open.xml b/Documentation/DocBook/media/v4l/cec-func-open.xml new file mode 100644 index 000000000000..2edc5555b81a --- /dev/null +++ b/Documentation/DocBook/media/v4l/cec-func-open.xml @@ -0,0 +1,104 @@ +<refentry id="cec-func-open"> + <refmeta> + <refentrytitle>cec open()</refentrytitle> + &manvol; + </refmeta> + + <refnamediv> + <refname>cec-open</refname> + <refpurpose>Open a cec device</refpurpose> + </refnamediv> + + <refsynopsisdiv> + <funcsynopsis> + <funcsynopsisinfo>#include <fcntl.h></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>. + </para> + <para>When the <constant>O_NONBLOCK</constant> flag is +given, the &CEC-RECEIVE; ioctl will return &EAGAIN; when no message is +available, and the &CEC-TRANSMIT;, &CEC-ADAP-S-PHYS-ADDR; and +&CEC-ADAP-S-LOG-ADDRS; ioctls all act in non-blocking mode.</para> + <para>Other flags have no effect.</para> + </listitem> + </varlistentry> + </variablelist> + </refsect1> + <refsect1> + <title>Description</title> + <para> + Note: this documents the proposed CEC API. This API is not yet finalized and + is currently only available as a staging kernel module. + </para> + + <para>To open a cec device applications call <function>open()</function> + with the desired device name. The function has no side effects; the device + configuration remain unchanged.</para> + <para>When the device is opened in read-only mode, attempts to modify its + configuration will result in an error, and <varname>errno</varname> will be + set to <errorcode>EBADF</errorcode>.</para> + </refsect1> + <refsect1> + <title>Return Value</title> + + <para><function>open</function> returns the new file descriptor on success. + On error, -1 is returned, and <varname>errno</varname> is set appropriately. + Possible error codes include:</para> + + <variablelist> + <varlistentry> + <term><errorcode>EACCES</errorcode></term> + <listitem> + <para>The requested access to the file is not allowed.</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 system limit on the total number of open files has been + reached.</para> + </listitem> + </varlistentry> + <varlistentry> + <term><errorcode>ENOMEM</errorcode></term> + <listitem> + <para>Insufficient kernel memory was available.</para> + </listitem> + </varlistentry> + <varlistentry> + <term><errorcode>ENXIO</errorcode></term> + <listitem> + <para>No device corresponding to this device special file exists. + </para> + </listitem> + </varlistentry> + </variablelist> + </refsect1> +</refentry> |