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authorMauro Carvalho Chehab <mchehab@redhat.com>2011-05-31 23:27:44 +0400
committerMauro Carvalho Chehab <mchehab@redhat.com>2011-07-28 00:52:05 +0400
commit4266129964b8238526936d723de65b419d8069c6 (patch)
tree38c6b5cd3dc99b8599391ffad3b87e399bef56a2 /Documentation/DocBook/v4l/vidioc-g-fmt.xml
parent04893043ae9ea8aa82b712491ed25ba6c4ffbca3 (diff)
downloadlinux-4266129964b8238526936d723de65b419d8069c6.tar.xz
[media] DocBook: Move all media docbook stuff into its own directory
This patch addresses several issues pointed by Randy Dunlap <rdunlap@xenotime.net> at changeset ece722c: - In the generated index.html file, "media" is listed first, but it should be listed in alphabetical order, not first. - The generated files are (hidden) in .tmpmedia/ - The link from the top-level index.html file to "media" is to media/index.html, but the file is actually in .tmpmedia/media/index.html - Please build docs with and without using "O=builddir" and test that. - Would it be possible for media to have its own Makefile instead of merging into this one? Due to the way cleandocs target works, I had to rename the media DocBook to media_api, otherwise cleandocs would remove the /media directory. Thanks-to: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Diffstat (limited to 'Documentation/DocBook/v4l/vidioc-g-fmt.xml')
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diff --git a/Documentation/DocBook/v4l/vidioc-g-fmt.xml b/Documentation/DocBook/v4l/vidioc-g-fmt.xml
deleted file mode 100644
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--- a/Documentation/DocBook/v4l/vidioc-g-fmt.xml
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@@ -1,212 +0,0 @@
-<refentry id="vidioc-g-fmt">
- <refmeta>
- <refentrytitle>ioctl VIDIOC_G_FMT, VIDIOC_S_FMT,
-VIDIOC_TRY_FMT</refentrytitle>
- &manvol;
- </refmeta>
-
- <refnamediv>
- <refname>VIDIOC_G_FMT</refname>
- <refname>VIDIOC_S_FMT</refname>
- <refname>VIDIOC_TRY_FMT</refname>
- <refpurpose>Get or set the data format, try a format</refpurpose>
- </refnamediv>
-
- <refsynopsisdiv>
- <funcsynopsis>
- <funcprototype>
- <funcdef>int <function>ioctl</function></funcdef>
- <paramdef>int <parameter>fd</parameter></paramdef>
- <paramdef>int <parameter>request</parameter></paramdef>
- <paramdef>struct v4l2_format
-*<parameter>argp</parameter></paramdef>
- </funcprototype>
- </funcsynopsis>
- </refsynopsisdiv>
-
- <refsect1>
- <title>Arguments</title>
-
- <variablelist>
- <varlistentry>
- <term><parameter>fd</parameter></term>
- <listitem>
- <para>&fd;</para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><parameter>request</parameter></term>
- <listitem>
- <para>VIDIOC_G_FMT, VIDIOC_S_FMT, VIDIOC_TRY_FMT</para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><parameter>argp</parameter></term>
- <listitem>
- <para></para>
- </listitem>
- </varlistentry>
- </variablelist>
- </refsect1>
-
- <refsect1>
- <title>Description</title>
-
- <para>These ioctls are used to negotiate the format of data
-(typically image format) exchanged between driver and
-application.</para>
-
- <para>To query the current parameters applications set the
-<structfield>type</structfield> field of a struct
-<structname>v4l2_format</structname> to the respective buffer (stream)
-type. For example video capture devices use
-<constant>V4L2_BUF_TYPE_VIDEO_CAPTURE</constant> or
-<constant>V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE</constant>. When the application
-calls the <constant>VIDIOC_G_FMT</constant> ioctl with a pointer to
-this structure the driver fills the respective member of the
-<structfield>fmt</structfield> union. In case of video capture devices
-that is either the &v4l2-pix-format; <structfield>pix</structfield> or
-the &v4l2-pix-format-mplane; <structfield>pix_mp</structfield> member.
-When the requested buffer type is not supported drivers return an
-&EINVAL;.</para>
-
- <para>To change the current format parameters applications
-initialize the <structfield>type</structfield> field and all
-fields of the respective <structfield>fmt</structfield>
-union member. For details see the documentation of the various devices
-types in <xref linkend="devices" />. Good practice is to query the
-current parameters first, and to
-modify only those parameters not suitable for the application. When
-the application calls the <constant>VIDIOC_S_FMT</constant> ioctl
-with a pointer to a <structname>v4l2_format</structname> structure
-the driver checks
-and adjusts the parameters against hardware abilities. Drivers
-should not return an error code unless the input is ambiguous, this is
-a mechanism to fathom device capabilities and to approach parameters
-acceptable for both the application and driver. On success the driver
-may program the hardware, allocate resources and generally prepare for
-data exchange.
-Finally the <constant>VIDIOC_S_FMT</constant> ioctl returns the
-current format parameters as <constant>VIDIOC_G_FMT</constant> does.
-Very simple, inflexible devices may even ignore all input and always
-return the default parameters. However all V4L2 devices exchanging
-data with the application must implement the
-<constant>VIDIOC_G_FMT</constant> and
-<constant>VIDIOC_S_FMT</constant> ioctl. When the requested buffer
-type is not supported drivers return an &EINVAL; on a
-<constant>VIDIOC_S_FMT</constant> attempt. When I/O is already in
-progress or the resource is not available for other reasons drivers
-return the &EBUSY;.</para>
-
- <para>The <constant>VIDIOC_TRY_FMT</constant> ioctl is equivalent
-to <constant>VIDIOC_S_FMT</constant> with one exception: it does not
-change driver state. It can also be called at any time, never
-returning <errorcode>EBUSY</errorcode>. This function is provided to
-negotiate parameters, to learn about hardware limitations, without
-disabling I/O or possibly time consuming hardware preparations.
-Although strongly recommended drivers are not required to implement
-this ioctl.</para>
-
- <table pgwide="1" frame="none" id="v4l2-format">
- <title>struct <structname>v4l2_format</structname></title>
- <tgroup cols="4">
- <colspec colname="c1" />
- <colspec colname="c2" />
- <colspec colname="c3" />
- <colspec colname="c4" />
- <tbody valign="top">
- <row>
- <entry>&v4l2-buf-type;</entry>
- <entry><structfield>type</structfield></entry>
- <entry></entry>
- <entry>Type of the data stream, see <xref
- linkend="v4l2-buf-type" />.</entry>
- </row>
- <row>
- <entry>union</entry>
- <entry><structfield>fmt</structfield></entry>
- </row>
- <row>
- <entry></entry>
- <entry>&v4l2-pix-format;</entry>
- <entry><structfield>pix</structfield></entry>
- <entry>Definition of an image format, see <xref
- linkend="pixfmt" />, used by video capture and output
-devices.</entry>
- </row>
- <row>
- <entry></entry>
- <entry>&v4l2-pix-format-mplane;</entry>
- <entry><structfield>pix_mp</structfield></entry>
- <entry>Definition of an image format, see <xref
- linkend="pixfmt" />, used by video capture and output
-devices that support the <link linkend="planar-apis">multi-planar
-version of the API</link>.</entry>
- </row>
- <row>
- <entry></entry>
- <entry>&v4l2-window;</entry>
- <entry><structfield>win</structfield></entry>
- <entry>Definition of an overlaid image, see <xref
- linkend="overlay" />, used by video overlay devices.</entry>
- </row>
- <row>
- <entry></entry>
- <entry>&v4l2-vbi-format;</entry>
- <entry><structfield>vbi</structfield></entry>
- <entry>Raw VBI capture or output parameters. This is
-discussed in more detail in <xref linkend="raw-vbi" />. Used by raw VBI
-capture and output devices.</entry>
- </row>
- <row>
- <entry></entry>
- <entry>&v4l2-sliced-vbi-format;</entry>
- <entry><structfield>sliced</structfield></entry>
- <entry>Sliced VBI capture or output parameters. See
-<xref linkend="sliced" /> for details. Used by sliced VBI
-capture and output devices.</entry>
- </row>
- <row>
- <entry></entry>
- <entry>__u8</entry>
- <entry><structfield>raw_data</structfield>[200]</entry>
- <entry>Place holder for future extensions and custom
-(driver defined) formats with <structfield>type</structfield>
-<constant>V4L2_BUF_TYPE_PRIVATE</constant> and higher.</entry>
- </row>
- </tbody>
- </tgroup>
- </table>
- </refsect1>
-
- <refsect1>
- &return-value;
-
- <variablelist>
- <varlistentry>
- <term><errorcode>EBUSY</errorcode></term>
- <listitem>
- <para>The data format cannot be changed at this
-time, for example because I/O is already in progress.</para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><errorcode>EINVAL</errorcode></term>
- <listitem>
- <para>The &v4l2-format; <structfield>type</structfield>
-field is invalid, the requested buffer type not supported, or
-<constant>VIDIOC_TRY_FMT</constant> was called and is not
-supported with this buffer type.</para>
- </listitem>
- </varlistentry>
- </variablelist>
- </refsect1>
-</refentry>
-
-<!--
-Local Variables:
-mode: sgml
-sgml-parent-document: "v4l2.sgml"
-indent-tabs-mode: nil
-End:
--->