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authorLinus Torvalds <torvalds@linux-foundation.org>2009-12-16 10:09:16 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2009-12-16 10:09:16 -0800
commit6a5df38f5f07981dda5457ec6c05efe1c4200d84 (patch)
treed82c3862f7ba719d7723111140a0c89e6387cb19 /Documentation/DocBook/v4l/common.xml
parent9cfc86249f32d984339c6d1f8a1fd1326989b3b8 (diff)
parent262ab9ac0daadebcece8e3cbf3ae66ee8774cfd7 (diff)
Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6: (116 commits) V4L/DVB (13698): pms: replace asm/uaccess.h to linux/uaccess.h V4L/DVB (13690): radio/si470x: #include <sched.h> V4L/DVB (13688): au8522: modify the attributes of local filter coefficients V4L/DVB (13687): cx231xx: use NULL when pointer is needed V4L/DVB: Davinci VPFE Capture: remove unused #include <linux/version.h> V4L/DVB (13685): Correct code taking the size of a pointer V4L/DVB (13684): Fix some cut-and-paste noise in dib0090.h V4L/DVB (13683): sanio-ms: clean up init, exit and id_table V4L/DVB (13682): dib8000: make some constant static V4L/DVB: lgs8gxx: Use shifts rather than multiply/divide when possible V4L/DVB (13680b): DocBook/media: create links for included sources V4L/DVB (13680a): DocBook/media: copy images after building HTML V4L/DVB (13678): Add support for yet another DvbWorld, TeVii and Prof USB devices V4L/DVB (13676): configurable IRQ mode on NetUP Dual DVB-S2 CI; IRQ from CAM processing (CI interface works faster) V4L/DVB (13674): stv090x: Add DiSEqC envelope mode V4L/DVB (13673): lnbp21: Implement 22 kHz tone control V4L/DVB (13671): sh_mobile_ceu_camera: Remove frame size page alignment V4L/DVB (13670): soc-camera: Add mt9t112 camera driver V4L/DVB (13669): tw9910: Add sync polarity support V4L/DVB (13668): tw9910: remove cropping ...
Diffstat (limited to 'Documentation/DocBook/v4l/common.xml')
-rw-r--r--Documentation/DocBook/v4l/common.xml35
1 files changed, 35 insertions, 0 deletions
diff --git a/Documentation/DocBook/v4l/common.xml b/Documentation/DocBook/v4l/common.xml
index b1a81d246d5..c65f0ac9b6e 100644
--- a/Documentation/DocBook/v4l/common.xml
+++ b/Documentation/DocBook/v4l/common.xml
@@ -716,6 +716,41 @@ if (-1 == ioctl (fd, &VIDIOC-S-STD;, &amp;std_id)) {
}
</programlisting>
</example>
+ <section id="dv-timings">
+ <title>Digital Video (DV) Timings</title>
+ <para>
+ The video standards discussed so far has been dealing with Analog TV and the
+corresponding video timings. Today there are many more different hardware interfaces
+such as High Definition TV interfaces (HDMI), VGA, DVI connectors etc., that carry
+video signals and there is a need to extend the API to select the video timings
+for these interfaces. Since it is not possible to extend the &v4l2-std-id; due to
+the limited bits available, a new set of IOCTLs is added to set/get video timings at
+the input and output: </para><itemizedlist>
+ <listitem>
+ <para>DV Presets: Digital Video (DV) presets. These are IDs representing a
+video timing at the input/output. Presets are pre-defined timings implemented
+by the hardware according to video standards. A __u32 data type is used to represent
+a preset unlike the bit mask that is used in &v4l2-std-id; allowing future extensions
+to support as many different presets as needed.</para>
+ </listitem>
+ <listitem>
+ <para>Custom DV Timings: This will allow applications to define more detailed
+custom video timings for the interface. This includes parameters such as width, height,
+polarities, frontporch, backporch etc.
+ </para>
+ </listitem>
+ </itemizedlist>
+ <para>To enumerate and query the attributes of DV presets supported by a device,
+applications use the &VIDIOC-ENUM-DV-PRESETS; ioctl. To get the current DV preset,
+applications use the &VIDIOC-G-DV-PRESET; ioctl and to set a preset they use the
+&VIDIOC-S-DV-PRESET; ioctl.</para>
+ <para>To set custom DV timings for the device, applications use the
+&VIDIOC-S-DV-TIMINGS; ioctl and to get current custom DV timings they use the
+&VIDIOC-G-DV-TIMINGS; ioctl.</para>
+ <para>Applications can make use of the <xref linkend="input-capabilities" /> and
+<xref linkend="output-capabilities"/> flags to decide what ioctls are available to set the
+video timings for the device.</para>
+ </section>
</section>
&sub-controls;