Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit b4e96a7e authored by Andrey Smirnov's avatar Andrey Smirnov Committed by Mauro Carvalho Chehab
Browse files

[media] v4l2: Add documentation for the FM RX controls 

Add appropriate documentation for all the newly added standard
controls.
Based on the patch by Manjunatha Halli [1]
[1] http://lists-archives.com/linux-kernel/27641303-media-update-docs-for-v4l2-fm-new-features.html



Acked-by: default avatarHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: default avatarAndrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab@redhat.com>
parent aec330a8

Documentation/DocBook/media/v4l/compat.xml

+3 −0
Original line number Diff line number Diff line
@@ -2310,6 +2310,9 @@ more information.</para> 
	<listitem>

	  <para>Added FM Modulator (FM TX) Extended Control Class: <constant>V4L2_CTRL_CLASS_FM_TX</constant> and their Control IDs.</para>

	</listitem>

<listitem>

	  <para>Added FM Receiver (FM RX) Extended Control Class: <constant>V4L2_CTRL_CLASS_FM_RX</constant> and their Control IDs.</para>

	</listitem>

	<listitem>

	  <para>Added Remote Controller chapter, describing the default Remote Controller mapping for media devices.</para>

	</listitem>

Documentation/DocBook/media/v4l/controls.xml

+72 −0
Original line number Diff line number Diff line
@@ -4693,4 +4693,76 @@ interface and may change in the future.</para> 
      </table>



    </section>



    <section id="fm-rx-controls">

      <title>FM Receiver Control Reference</title>



      <para>The FM Receiver (FM_RX) class includes controls for common features of

      FM Reception capable devices.</para>



      <table pgwide="1" frame="none" id="fm-rx-control-id">

      <title>FM_RX 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_FM_RX_CLASS</constant>&nbsp;</entry>

            <entry>class</entry>

          </row><row><entry spanname="descr">The FM_RX 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_RDS_RECEPTION</constant>&nbsp;</entry>

            <entry>boolean</entry>

          </row><row><entry spanname="descr">Enables/disables RDS

	  reception by the radio tuner</entry>

          </row>

          <row>

	    <entry spanname="id"><constant>V4L2_CID_TUNE_DEEMPHASIS</constant>&nbsp;</entry>

	    <entry>enum v4l2_deemphasis</entry>

	  </row>

	  <row id="v4l2-deemphasis"><entry spanname="descr">Configures the de-emphasis value for reception.

A de-emphasis filter is applied to the broadcast to accentuate the high audio frequencies.

Depending on the region, a time constant of either 50 or 75 useconds is used. The enum&nbsp;v4l2_deemphasis

defines possible values for de-emphasis. Here they are:</entry>

	</row><row>

	<entrytbl spanname="descr" cols="2">

		  <tbody valign="top">

		    <row>

		      <entry><constant>V4L2_DEEMPHASIS_DISABLED</constant>&nbsp;</entry>

		      <entry>No de-emphasis is applied.</entry>

		    </row>

		    <row>

		      <entry><constant>V4L2_DEEMPHASIS_50_uS</constant>&nbsp;</entry>

		      <entry>A de-emphasis of 50 uS is used.</entry>

		    </row>

		    <row>

		      <entry><constant>V4L2_DEEMPHASIS_75_uS</constant>&nbsp;</entry>

		      <entry>A de-emphasis of 75 uS is used.</entry>

		    </row>

		  </tbody>

		</entrytbl>



	  </row>

          <row><entry></entry></row>

        </tbody>

      </tgroup>

      </table>



      </section>

</section>

Documentation/DocBook/media/v4l/vidioc-g-ext-ctrls.xml

+9 −0
Original line number Diff line number Diff line
@@ -319,6 +319,15 @@ These controls are described in <xref 
	    processing controls. These controls are described in <xref

	    linkend="image-process-controls" />.</entry>

	  </row>



	  <row>

	    <entry><constant>V4L2_CTRL_CLASS_FM_RX</constant></entry>

	    <entry>0xa10000</entry>

	    <entry>The class containing FM Receiver (FM RX) controls.

These controls are described in <xref

		linkend="fm-rx-controls" />.</entry>

	  </row>



	</tbody>

      </tgroup>

    </table>