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authorAntti Palosaari <crope@iki.fi>2015-10-10 19:50:59 +0300
committerMauro Carvalho Chehab <mchehab@osg.samsung.com>2015-10-20 20:39:37 +0300
commitb2411b93cdcb5cb154827b8fcd2f436dd0ddab73 (patch)
tree8d1b2c341cc16411b3a727e9156adb56f59a3e4e /Documentation/DocBook
parent41018cb84a9ed440db1508d67d9dd4084d5460eb (diff)
downloadlinux-b2411b93cdcb5cb154827b8fcd2f436dd0ddab73.tar.xz
[media] DocBook: document tuner RF gain control
Add brief description for tuner RF gain control. Signed-off-by: Antti Palosaari <crope@iki.fi> Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Diffstat (limited to 'Documentation/DocBook')
-rw-r--r--Documentation/DocBook/media/v4l/compat.xml4
-rw-r--r--Documentation/DocBook/media/v4l/controls.xml14
-rw-r--r--Documentation/DocBook/media/v4l/v4l2.xml1
3 files changed, 19 insertions, 0 deletions
diff --git a/Documentation/DocBook/media/v4l/compat.xml b/Documentation/DocBook/media/v4l/compat.xml
index 08f4efcab4e9..6c4e95146d16 100644
--- a/Documentation/DocBook/media/v4l/compat.xml
+++ b/Documentation/DocBook/media/v4l/compat.xml
@@ -2600,6 +2600,10 @@ and &v4l2-mbus-framefmt;.
<constant>V4L2_TUNER_ADC</constant> is deprecated now.
</para>
</listitem>
+ <listitem>
+ <para>Added <constant>V4L2_CID_RF_TUNER_RF_GAIN</constant>
+RF Tuner control.</para>
+ </listitem>
</orderedlist>
</section>
diff --git a/Documentation/DocBook/media/v4l/controls.xml b/Documentation/DocBook/media/v4l/controls.xml
index 33aece541880..f13a429093f1 100644
--- a/Documentation/DocBook/media/v4l/controls.xml
+++ b/Documentation/DocBook/media/v4l/controls.xml
@@ -5418,6 +5418,18 @@ set. Unit is in Hz. The range and step are driver-specific.</entry>
<entry spanname="descr">Enables/disables IF automatic gain control (AGC)</entry>
</row>
<row>
+ <entry spanname="id"><constant>V4L2_CID_RF_TUNER_RF_GAIN</constant>&nbsp;</entry>
+ <entry>integer</entry>
+ </row>
+ <row>
+ <entry spanname="descr">The RF amplifier is the very first
+amplifier on the receiver signal path, just right after the antenna input.
+The difference between the LNA gain and the RF gain in this document is that
+the LNA gain is integrated in the tuner chip while the RF gain is a separate
+chip. There may be both RF and LNA gain controls in the same device.
+The range and step are driver-specific.</entry>
+ </row>
+ <row>
<entry spanname="id"><constant>V4L2_CID_RF_TUNER_LNA_GAIN</constant>&nbsp;</entry>
<entry>integer</entry>
</row>
@@ -5425,6 +5437,8 @@ set. Unit is in Hz. The range and step are driver-specific.</entry>
<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.
+See <constant>V4L2_CID_RF_TUNER_RF_GAIN</constant> to understand how RF gain
+and LNA gain differs from the each others.
The range and step are driver-specific.</entry>
</row>
<row>
diff --git a/Documentation/DocBook/media/v4l/v4l2.xml b/Documentation/DocBook/media/v4l/v4l2.xml
index 01a24df92e1d..9cc4117644fc 100644
--- a/Documentation/DocBook/media/v4l/v4l2.xml
+++ b/Documentation/DocBook/media/v4l/v4l2.xml
@@ -156,6 +156,7 @@ applications. -->
<date>2015-05-26</date>
<authorinitials>ap</authorinitials>
<revremark>Renamed V4L2_TUNER_ADC to V4L2_TUNER_SDR.
+Added V4L2_CID_RF_TUNER_RF_GAIN control.
</revremark>
</revision>