[media] DocBook: document RF tuner gain controls

Add documentation for LNA, mixer and IF gain controls. These
controls are RF tuner specific.

Signed-off-by: Antti Palosaari <crope@iki.fi>
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
This commit is contained in:
Antti Palosaari 2014-01-30 00:00:10 -03:00 committed by Mauro Carvalho Chehab
parent 951d9953c4
commit 851897a4ad

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@ -4991,4 +4991,95 @@ defines possible values for de-emphasis. Here they are:</entry>
</table>
</section>
<section id="rf-tuner-controls">
<title>RF Tuner Control Reference</title>
<para>The RF Tuner (RF_TUNER) class includes controls for common features
of devices having RF tuner.</para>
<table pgwide="1" frame="none" id="rf-tuner-control-id">
<title>RF_TUNER Control IDs</title>
<tgroup cols="4">
<colspec colname="c1" colwidth="1*" />
<colspec colname="c2" colwidth="6*" />
<colspec colname="c3" colwidth="2*" />
<colspec colname="c4" colwidth="6*" />
<spanspec namest="c1" nameend="c2" spanname="id" />
<spanspec namest="c2" nameend="c4" spanname="descr" />
<thead>
<row>
<entry spanname="id" align="left">ID</entry>
<entry align="left">Type</entry>
</row>
<row rowsep="1">
<entry spanname="descr" align="left">Description</entry>
</row>
</thead>
<tbody valign="top">
<row><entry></entry></row>
<row>
<entry spanname="id"><constant>V4L2_CID_RF_TUNER_CLASS</constant>&nbsp;</entry>
<entry>class</entry>
</row><row><entry spanname="descr">The RF_TUNER class
descriptor. Calling &VIDIOC-QUERYCTRL; for this control will return a
description of this control class.</entry>
</row>
<row>
<entry spanname="id"><constant>V4L2_CID_RF_TUNER_LNA_GAIN_AUTO</constant>&nbsp;</entry>
<entry>boolean</entry>
</row>
<row>
<entry spanname="descr">Enables/disables LNA automatic gain control (AGC)</entry>
</row>
<row>
<entry spanname="id"><constant>V4L2_CID_RF_TUNER_MIXER_GAIN_AUTO</constant>&nbsp;</entry>
<entry>boolean</entry>
</row>
<row>
<entry spanname="descr">Enables/disables mixer automatic gain control (AGC)</entry>
</row>
<row>
<entry spanname="id"><constant>V4L2_CID_RF_TUNER_IF_GAIN_AUTO</constant>&nbsp;</entry>
<entry>boolean</entry>
</row>
<row>
<entry spanname="descr">Enables/disables IF automatic gain control (AGC)</entry>
</row>
<row>
<entry spanname="id"><constant>V4L2_CID_RF_TUNER_LNA_GAIN</constant>&nbsp;</entry>
<entry>integer</entry>
</row>
<row>
<entry spanname="descr">LNA (low noise amplifier) gain is first
gain stage on the RF tuner signal path. It is located very close to tuner
antenna input. Used when <constant>V4L2_CID_RF_TUNER_LNA_GAIN_AUTO</constant> is not set.
The range and step are driver-specific.</entry>
</row>
<row>
<entry spanname="id"><constant>V4L2_CID_RF_TUNER_MIXER_GAIN</constant>&nbsp;</entry>
<entry>integer</entry>
</row>
<row>
<entry spanname="descr">Mixer gain is second gain stage on the RF
tuner signal path. It is located inside mixer block, where RF signal is
down-converted by the mixer. Used when <constant>V4L2_CID_RF_TUNER_MIXER_GAIN_AUTO</constant>
is not set. The range and step are driver-specific.</entry>
</row>
<row>
<entry spanname="id"><constant>V4L2_CID_RF_TUNER_IF_GAIN</constant>&nbsp;</entry>
<entry>integer</entry>
</row>
<row>
<entry spanname="descr">IF gain is last gain stage on the RF tuner
signal path. It is located on output of RF tuner. It controls signal level of
intermediate frequency output or baseband output. Used when
<constant>V4L2_CID_RF_TUNER_IF_GAIN_AUTO</constant> is not set. The range and step are
driver-specific.</entry>
</row>
</tbody>
</tgroup>
</table>
</section>
</section>