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6. fe-get-info.xml

<refentry id="FE_GET_INFO">
  <refmeta>
    <refentrytitle>ioctl FE_GET_INFO</refentrytitle>
    &manvol;
  </refmeta>

  <refnamediv>
    <refname>FE_GET_INFO</refname>
    <refpurpose>Query DVB frontend capabilities and returns information about
	the front-end. This call only requires read-only access to the device</refpurpose>
  </refnamediv>

  <refsynopsisdiv>
    <funcsynopsis>
      <funcprototype>
	<funcdef>int <function>ioctl</function></funcdef>
	<paramdef>int <parameter>fd</parameter></paramdef>
	<paramdef>int <parameter>request</parameter></paramdef>
	<paramdef>struct dvb_frontend_info *<parameter>argp</parameter></paramdef>
      </funcprototype>
    </funcsynopsis>
  </refsynopsisdiv>

  <refsect1>
    <title>Arguments</title>
        <variablelist>
      <varlistentry>
	<term><parameter>fd</parameter></term>
	<listitem>
	  <para>&fe_fd;</para>
	</listitem>
      </varlistentry>
      <varlistentry>
	<term><parameter>request</parameter></term>
	<listitem>
	  <para>FE_GET_INFO</para>
	</listitem>
      </varlistentry>
      <varlistentry>
	<term><parameter>argp</parameter></term>
	<listitem>
	    <para>pointer to struct &dvb-frontend-info;</para>
	</listitem>
      </varlistentry>
    </variablelist>
  </refsect1>

  <refsect1>
    <title>Description</title>

    <para>All DVB frontend devices support the
<constant>FE_GET_INFO</constant> ioctl. It is used to identify
kernel devices compatible with this specification and to obtain
information about driver and hardware capabilities. The ioctl takes a
pointer to dvb_frontend_info which is filled by the driver. When the
driver is not compatible with this specification the ioctl returns an error.
</para>
&return-value-dvb;

    <table pgwide="1" frame="none" id="dvb-frontend-info">
      <title>struct <structname>dvb_frontend_info</structname></title>
      <tgroup cols="3">
	&cs-str;
	<tbody valign="top">
	  <row>
	    <entry>char</entry>
	    <entry>name[128]</entry>
	    <entry>Name of the frontend</entry>
	  </row><row>
	    <entry>fe_type_t</entry>
	    <entry>type</entry>
	    <entry><emphasis role="bold">DEPRECATED</emphasis>. DVBv3 type. Should not be used on modern programs, as a
		frontend may have more than one type. So, the DVBv5 API should
		be used instead to enumerate and select the frontend type.</entry>
	  </row><row>
	    <entry>uint32_t</entry>
	    <entry>frequency_min</entry>
	    <entry>Minimal frequency supported by the frontend</entry>
	  </row><row>
	    <entry>uint32_t</entry>
	    <entry>frequency_max</entry>
	    <entry>Maximal frequency supported by the frontend</entry>
	  </row><row>
	    <entry>uint32_t</entry>
	    <entry>frequency_stepsize</entry>
	    <entry>Frequency step - all frequencies are multiple of this value</entry>
	  </row><row>
	    <entry>uint32_t</entry>
	    <entry>frequency_tolerance</entry>
	    <entry>Tolerance of the frequency</entry>
	  </row><row>
	    <entry>uint32_t</entry>
	    <entry>symbol_rate_min</entry>
	    <entry>Minimal symbol rate (for Cable/Satellite systems), in bauds</entry>
	  </row><row>
	    <entry>uint32_t</entry>
	    <entry>symbol_rate_max</entry>
	    <entry>Maximal symbol rate (for Cable/Satellite systems), in bauds</entry>
	  </row><row>
	    <entry>uint32_t</entry>
	    <entry>symbol_rate_tolerance</entry>
	    <entry>Maximal symbol rate tolerance, in ppm</entry>
	  </row><row>
	    <entry>uint32_t</entry>
	    <entry>notifier_delay</entry>
	    <entry><emphasis role="bold">DEPRECATED</emphasis>. Not used by any driver.</entry>
	  </row><row>
	    <entry>&fe-caps;</entry>
	    <entry>caps</entry>
	    <entry>Capabilities supported by the frontend</entry>
          </row>
	</tbody>
      </tgroup>
    </table>

  <para>NOTE: The frequencies are specified in Hz for Terrestrial and Cable
      systems. They're specified in kHz for Satellite systems</para>
  </refsect1>

<refsect1 id="fe-caps-t">
<title>frontend capabilities</title>

<para>Capabilities describe what a frontend can do. Some capabilities are
    supported only on some specific frontend types.</para>

<table pgwide="1" frame="none" id="fe-caps">
    <title>enum fe_caps</title>
    <tgroup cols="2">
	&cs-def;
	<thead>
	<row>
	    <entry>ID</entry>
	    <entry>Description</entry>
	</row>
	</thead>
	<tbody valign="top">
	<row>
	<entry id="FE-IS-STUPID"><constant>FE_IS_STUPID</constant></entry>
	<entry>There's something wrong at the frontend, and it can't
	    report its capabilities</entry>
	</row>
	<row>
	<entry id="FE-CAN-INVERSION-AUTO"><constant>FE_CAN_INVERSION_AUTO</constant></entry>
	<entry>The frontend is capable of auto-detecting inversion</entry>
	</row>
	<row>
	<entry id="FE-CAN-FEC-1-2"><constant>FE_CAN_FEC_1_2</constant></entry>
	<entry>The frontend supports FEC 1/2</entry>
	</row>
	<row>
	<entry id="FE-CAN-FEC-2-3"><constant>FE_CAN_FEC_2_3</constant></entry>
	<entry>The frontend supports FEC 2/3</entry>
	</row>
	<row>
	<entry id="FE-CAN-FEC-3-4"><constant>FE_CAN_FEC_3_4</constant></entry>
	<entry>The frontend supports FEC 3/4</entry>
	</row>
	<row>
	<entry id="FE-CAN-FEC-4-5"><constant>FE_CAN_FEC_4_5</constant></entry>
	<entry>The frontend supports FEC 4/5</entry>
	</row>
	<row>
	<entry id="FE-CAN-FEC-5-6"><constant>FE_CAN_FEC_5_6</constant></entry>
	<entry>The frontend supports FEC 5/6</entry>
	</row>
	<row>
	<entry id="FE-CAN-FEC-6-7"><constant>FE_CAN_FEC_6_7</constant></entry>
	<entry>The frontend supports FEC 6/7</entry>
	</row>
	<row>
	<entry id="FE-CAN-FEC-7-8"><constant>FE_CAN_FEC_7_8</constant></entry>
	<entry>The frontend supports FEC 7/8</entry>
	</row>
	<row>
	<entry id="FE-CAN-FEC-8-9"><constant>FE_CAN_FEC_8_9</constant></entry>
	<entry>The frontend supports FEC 8/9</entry>
	</row>
	<row>
	<entry id="FE-CAN-FEC-AUTO"><constant>FE_CAN_FEC_AUTO</constant></entry>
	<entry>The frontend can autodetect FEC.</entry>
	</row>
	<row>
	<entry id="FE-CAN-QPSK"><constant>FE_CAN_QPSK</constant></entry>
	<entry>The frontend supports QPSK modulation</entry>
	</row>
	<row>
	<entry id="FE-CAN-QAM-16"><constant>FE_CAN_QAM_16</constant></entry>
	<entry>The frontend supports 16-QAM modulation</entry>
	</row>
	<row>
	<entry id="FE-CAN-QAM-32"><constant>FE_CAN_QAM_32</constant></entry>
	<entry>The frontend supports 32-QAM modulation</entry>
	</row>
	<row>
	<entry id="FE-CAN-QAM-64"><constant>FE_CAN_QAM_64</constant></entry>
	<entry>The frontend supports 64-QAM modulation</entry>
	</row>
	<row>
	<entry id="FE-CAN-QAM-128"><constant>FE_CAN_QAM_128</constant></entry>
	<entry>The frontend supports 128-QAM modulation</entry>
	</row>
	<row>
	<entry id="FE-CAN-QAM-256"><constant>FE_CAN_QAM_256</constant></entry>
	<entry>The frontend supports 256-QAM modulation</entry>
	</row>
	<row>
	<entry id="FE-CAN-QAM-AUTO"><constant>FE_CAN_QAM_AUTO</constant></entry>
	<entry>The frontend can autodetect modulation</entry>
	</row>
	<row>
	<entry id="FE-CAN-TRANSMISSION-MODE-AUTO"><constant>FE_CAN_TRANSMISSION_MODE_AUTO</constant></entry>
	<entry>The frontend can autodetect the transmission mode</entry>
	</row>
	<row>
	<entry id="FE-CAN-BANDWIDTH-AUTO"><constant>FE_CAN_BANDWIDTH_AUTO</constant></entry>
	<entry>The frontend can autodetect the bandwidth</entry>
	</row>
	<row>
	<entry id="FE-CAN-GUARD-INTERVAL-AUTO"><constant>FE_CAN_GUARD_INTERVAL_AUTO</constant></entry>
	<entry>The frontend can autodetect the guard interval</entry>
	</row>
	<row>
	<entry id="FE-CAN-HIERARCHY-AUTO"><constant>FE_CAN_HIERARCHY_AUTO</constant></entry>
	<entry>The frontend can autodetect hierarch</entry>
	</row>
	<row>
	<entry id="FE-CAN-8VSB"><constant>FE_CAN_8VSB</constant></entry>
	<entry>The frontend supports 8-VSB modulation</entry>
	</row>
	<row>
	<entry id="FE-CAN-16VSB"><constant>FE_CAN_16VSB</constant></entry>
	<entry>The frontend supports 16-VSB modulation</entry>
	</row>
	<row>
	<entry id="FE-HAS-EXTENDED-CAPS"><constant>FE_HAS_EXTENDED_CAPS</constant></entry>
	<entry>Currently, unused</entry>
	</row>
	<row>
	<entry id="FE-CAN-MULTISTREAM"><constant>FE_CAN_MULTISTREAM</constant></entry>
	<entry>The frontend supports multistream filtering</entry>
	</row>
	<row>
	<entry id="FE-CAN-TURBO-FEC"><constant>FE_CAN_TURBO_FEC</constant></entry>
	<entry>The frontend supports turbo FEC modulation</entry>
	</row>
	<row>
	<entry id="FE-CAN-2G-MODULATION"><constant>FE_CAN_2G_MODULATION</constant></entry>
	<entry>The frontend supports "2nd generation modulation" (DVB-S2/T2)></entry>
	</row>
	<row>
	<entry id="FE-NEEDS-BENDING"><constant>FE_NEEDS_BENDING</constant></entry>
	<entry>Not supported anymore, don't use it</entry>
	</row>
	<row>
	<entry id="FE-CAN-RECOVER"><constant>FE_CAN_RECOVER</constant></entry>
	<entry>The frontend can recover from a cable unplug automatically</entry>
	</row>
	<row>
	<entry id="FE-CAN-MUTE-TS"><constant>FE_CAN_MUTE_TS</constant></entry>
	<entry>The frontend can stop spurious TS data output</entry>
	</row>
        </tbody>
    </tgroup>
</table>
</refsect1>
</refentry>