[media] v4l: Image processing control class

Add control class for image processing controls. The control class deals
with controls processing image, for example digital gain or noise filtering,
which can be present in any part of the pipeline.

Signed-off-by: Sakari Ailus <sakari.ailus@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

2 files changed, 88 insertions, 0 deletions

diff --git a/Documentation/DocBook/media/v4l/controls.xml b/Documentation/DocBook/media/v4l/controls.xml
index 43cd4958c9e8..662127447aa6 100644
--- a/Documentation/DocBook/media/v4l/controls.xml
+++ b/Documentation/DocBook/media/v4l/controls.xml
@@ -3685,4 +3685,86 @@ interface and may change in the future.</para>
 
     </section>
 
+    <section id="image-process-controls">
+      <title>Image Process Control Reference</title>
+
+      <note>
+        <title>Experimental</title>
+
+        <para>This is an <link
+        linkend="experimental">experimental</link> interface and may
+        change in the future.</para>
+      </note>
+
+      <para>
+        The Image Source control class is intended for low-level control of
+        image processing functions. Unlike
+        <constant>V4L2_CID_IMAGE_SOURCE_CLASS</constant>, the controls in
+        this class affect processing the image, and do not control capturing
+        of it.
+      </para>
+
+      <table pgwide="1" frame="none" id="image-process-control-id">
+      <title>Image Source 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_IMAGE_PROC_CLASS</constant></entry>
+            <entry>class</entry>
+          </row>
+          <row>
+            <entry spanname="descr">The IMAGE_PROC class descriptor.</entry>
+          </row>
+          <row>
+            <entry spanname="id"><constant>V4L2_CID_LINK_FREQ</constant></entry>
+            <entry>integer menu</entry>
+          </row>
+          <row>
+            <entry spanname="descr">Data bus frequency. Together with the
+            media bus pixel code, bus type (clock cycles per sample), the
+            data bus frequency defines the pixel rate
+            (<constant>V4L2_CID_PIXEL_RATE</constant>) in the
+            pixel array (or possibly elsewhere, if the device is not an
+            image sensor). The frame rate can be calculated from the pixel
+            clock, image width and height and horizontal and vertical
+            blanking. While the pixel rate control may be defined elsewhere
+            than in the subdev containing the pixel array, the frame rate
+            cannot be obtained from that information. This is because only
+            on the pixel array it can be assumed that the vertical and
+            horizontal blanking information is exact: no other blanking is
+            allowed in the pixel array. The selection of frame rate is
+            performed by selecting the desired horizontal and vertical
+            blanking. The unit of this control is Hz. </entry>
+          </row>
+          <row>
+            <entry spanname="id"><constant>V4L2_CID_PIXEL_RATE</constant></entry>
+            <entry>64-bit integer</entry>
+          </row>
+          <row>
+            <entry spanname="descr">Pixel rate in the source pads of
+            the subdev. This control is read-only and its unit is
+            pixels / second.
+            </entry>
+          </row>
+          <row><entry></entry></row>
+        </tbody>
+      </tgroup>
+      </table>
+
+    </section>
 </section>
diff --git a/Documentation/DocBook/media/v4l/vidioc-g-ext-ctrls.xml b/Documentation/DocBook/media/v4l/vidioc-g-ext-ctrls.xml
index f2d2ec3f0e31..0a4b90fcf2da 100644
--- a/Documentation/DocBook/media/v4l/vidioc-g-ext-ctrls.xml
+++ b/Documentation/DocBook/media/v4l/vidioc-g-ext-ctrls.xml
@@ -278,6 +278,12 @@ These controls are described in <xref
             source controls. These controls are described in <xref
             linkend="image-source-controls" />.</entry>
           </row>
+          <row>
+            <entry><constant>V4L2_CTRL_CLASS_IMAGE_PROC</constant></entry>
+            <entry>0x9f0000</entry> <entry>The class containing image
+            processing controls. These controls are described in <xref
+            linkend="image-process-controls" />.</entry>
+          </row>
         </tbody>
       </tgroup>
     </table>