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[media] v4l: Image source control class
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Add image source control class. This control class is intended to contain
low level controls which deal with control of the image capture process ---
the A/D converter in image sensors, for example.

Signed-off-by: Sakari Ailus <sakari.ailus@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
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Sakari Ailus authored and Mauro Carvalho Chehab committed May 14, 2012
1 parent 6016af8 commit 8c9d236
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86 changes: 86 additions & 0 deletions Documentation/DocBook/media/v4l/controls.xml
Original file line number Diff line number Diff line change
Expand Up @@ -3599,4 +3599,90 @@ interface and may change in the future.</para>
to <xref linkend="itu-t81"/>, <xref linkend="jfif"/>,
<xref linkend="w3c-jpeg-jfif"/>.</para>
</section>

<section id="image-source-controls">
<title>Image Source 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 source devices such as image sensors. The
devices feature an analogue to digital converter and a bus
transmitter to transmit the image data out of the device.
</para>

<table pgwide="1" frame="none" id="image-source-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_SOURCE_CLASS</constant></entry>
<entry>class</entry>
</row>
<row>
<entry spanname="descr">The IMAGE_SOURCE class descriptor.</entry>
</row>
<row>
<entry spanname="id"><constant>V4L2_CID_VBLANK</constant></entry>
<entry>integer</entry>
</row>
<row>
<entry spanname="descr">Vertical blanking. The idle period
after every frame during which no image data is produced.
The unit of vertical blanking is a line. Every line has
length of the image width plus horizontal blanking at the
pixel rate defined by
<constant>V4L2_CID_PIXEL_RATE</constant> control in the
same sub-device.</entry>
</row>
<row>
<entry spanname="id"><constant>V4L2_CID_HBLANK</constant></entry>
<entry>integer</entry>
</row>
<row>
<entry spanname="descr">Horizontal blanking. The idle
period after every line of image data during which no
image data is produced. The unit of horizontal blanking is
pixels.</entry>
</row>
<row>
<entry spanname="id"><constant>V4L2_CID_ANALOGUE_GAIN</constant></entry>
<entry>integer</entry>
</row>
<row>
<entry spanname="descr">Analogue gain is gain affecting
all colour components in the pixel matrix. The gain
operation is performed in the analogue domain before A/D
conversion.
</entry>
</row>
<row><entry></entry></row>
</tbody>
</tgroup>
</table>

</section>

</section>
6 changes: 6 additions & 0 deletions Documentation/DocBook/media/v4l/vidioc-g-ext-ctrls.xml
Original file line number Diff line number Diff line change
Expand Up @@ -272,6 +272,12 @@ These controls are described in <xref
These controls are described in <xref
linkend="jpeg-controls" />.</entry>
</row>
<row>
<entry><constant>V4L2_CTRL_CLASS_IMAGE_SOURCE</constant></entry>
<entry>0x9e0000</entry> <entry>The class containing image
source controls. These controls are described in <xref
linkend="image-source-controls" />.</entry>
</row>
</tbody>
</tgroup>
</table>
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7 changes: 7 additions & 0 deletions drivers/media/video/v4l2-ctrls.c
Original file line number Diff line number Diff line change
Expand Up @@ -644,6 +644,12 @@ const char *v4l2_ctrl_get_name(u32 id)
case V4L2_CID_JPEG_COMPRESSION_QUALITY: return "Compression Quality";
case V4L2_CID_JPEG_ACTIVE_MARKER: return "Active Markers";

/* Image source controls */
case V4L2_CID_IMAGE_SOURCE_CLASS: return "Image Source Controls";
case V4L2_CID_VBLANK: return "Vertical Blanking";
case V4L2_CID_HBLANK: return "Horizontal Blanking";
case V4L2_CID_ANALOGUE_GAIN: return "Analogue Gain";

default:
return NULL;
}
Expand Down Expand Up @@ -745,6 +751,7 @@ void v4l2_ctrl_fill(u32 id, const char **name, enum v4l2_ctrl_type *type,
case V4L2_CID_FM_TX_CLASS:
case V4L2_CID_FLASH_CLASS:
case V4L2_CID_JPEG_CLASS:
case V4L2_CID_IMAGE_SOURCE_CLASS:
*type = V4L2_CTRL_TYPE_CTRL_CLASS;
/* You can neither read not write these */
*flags |= V4L2_CTRL_FLAG_READ_ONLY | V4L2_CTRL_FLAG_WRITE_ONLY;
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9 changes: 9 additions & 0 deletions include/linux/videodev2.h
Original file line number Diff line number Diff line change
Expand Up @@ -1139,6 +1139,7 @@ struct v4l2_ext_controls {
#define V4L2_CTRL_CLASS_FM_TX 0x009b0000 /* FM Modulator control class */
#define V4L2_CTRL_CLASS_FLASH 0x009c0000 /* Camera flash controls */
#define V4L2_CTRL_CLASS_JPEG 0x009d0000 /* JPEG-compression controls */
#define V4L2_CTRL_CLASS_IMAGE_SOURCE 0x009e0000 /* Image source controls */

#define V4L2_CTRL_ID_MASK (0x0fffffff)
#define V4L2_CTRL_ID2CLASS(id) ((id) & 0x0fff0000UL)
Expand Down Expand Up @@ -1788,6 +1789,14 @@ enum v4l2_jpeg_chroma_subsampling {
#define V4L2_JPEG_ACTIVE_MARKER_DQT (1 << 17)
#define V4L2_JPEG_ACTIVE_MARKER_DHT (1 << 18)

/* Image source controls */
#define V4L2_CID_IMAGE_SOURCE_CLASS_BASE (V4L2_CTRL_CLASS_IMAGE_SOURCE | 0x900)
#define V4L2_CID_IMAGE_SOURCE_CLASS (V4L2_CTRL_CLASS_IMAGE_SOURCE | 1)

#define V4L2_CID_VBLANK (V4L2_CID_IMAGE_SOURCE_CLASS_BASE + 1)
#define V4L2_CID_HBLANK (V4L2_CID_IMAGE_SOURCE_CLASS_BASE + 2)
#define V4L2_CID_ANALOGUE_GAIN (V4L2_CID_IMAGE_SOURCE_CLASS_BASE + 3)

/*
* T U N I N G
*/
Expand Down

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