--- /dev/null
+<refentry id="vidioc-subdev-enum-frame-size">
+ <refmeta>
+ <refentrytitle>ioctl VIDIOC_SUBDEV_ENUM_FRAME_SIZE</refentrytitle>
+ &manvol;
+ </refmeta>
+
+ <refnamediv>
+ <refname>VIDIOC_SUBDEV_ENUM_FRAME_SIZE</refname>
+ <refpurpose>Enumerate media bus frame sizes</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_subdev_frame_size_enum *
+ <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_SUBDEV_ENUM_FRAME_SIZE</para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><parameter>argp</parameter></term>
+ <listitem>
+ <para></para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
+ </refsect1>
+
+ <refsect1>
+ <title>Description</title>
+
+ <note>
+ <title>Experimental</title>
+ <para>This is an <link linkend="experimental">experimental</link>
+ interface and may change in the future.</para>
+ </note>
+
+ <para>This ioctl allows applications to enumerate all frame sizes
+ supported by a sub-device on the given pad for the given media bus format.
+ Supported formats can be retrieved with the &VIDIOC-SUBDEV-ENUM-MBUS-CODE;
+ ioctl.</para>
+
+ <para>To enumerate frame sizes applications initialize the
+ <structfield>pad</structfield>, <structfield>which</structfield> ,
+ <structfield>code</structfield> and <structfield>index</structfield>
+ fields of the &v4l2-subdev-mbus-code-enum; and call the
+ <constant>VIDIOC_SUBDEV_ENUM_FRAME_SIZE</constant> ioctl with a pointer to
+ the structure. Drivers fill the minimum and maximum frame sizes or return
+ an &EINVAL; if one of the input parameters is invalid.</para>
+
+ <para>Sub-devices that only support discrete frame sizes (such as most
+ sensors) will return one or more frame sizes with identical minimum and
+ maximum values.</para>
+
+ <para>Not all possible sizes in given [minimum, maximum] ranges need to be
+ supported. For instance, a scaler that uses a fixed-point scaling ratio
+ might not be able to produce every frame size between the minimum and
+ maximum values. Applications must use the &VIDIOC-SUBDEV-S-FMT; ioctl to
+ try the sub-device for an exact supported frame size.</para>
+
+ <para>Available frame sizes may depend on the current 'try' formats at other
+ pads of the sub-device, as well as on the current active links and the
+ current values of V4L2 controls. See &VIDIOC-SUBDEV-G-FMT; for more
+ information about try formats.</para>
+
+ <table pgwide="1" frame="none" id="v4l2-subdev-frame-size-enum">
+ <title>struct <structname>v4l2_subdev_frame_size_enum</structname></title>
+ <tgroup cols="3">
+ &cs-str;
+ <tbody valign="top">
+ <row>
+ <entry>__u32</entry>
+ <entry><structfield>index</structfield></entry>
+ <entry>Number of the format in the enumeration, set by the
+ application.</entry>
+ </row>
+ <row>
+ <entry>__u32</entry>
+ <entry><structfield>pad</structfield></entry>
+ <entry>Pad number as reported by the media controller API.</entry>
+ </row>
+ <row>
+ <entry>__u32</entry>
+ <entry><structfield>code</structfield></entry>
+ <entry>The media bus format code, as defined in
+ <xref linkend="v4l2-mbus-format" />.</entry>
+ </row>
+ <row>
+ <entry>__u32</entry>
+ <entry><structfield>min_width</structfield></entry>
+ <entry>Minimum frame width, in pixels.</entry>
+ </row>
+ <row>
+ <entry>__u32</entry>
+ <entry><structfield>max_width</structfield></entry>
+ <entry>Maximum frame width, in pixels.</entry>
+ </row>
+ <row>
+ <entry>__u32</entry>
+ <entry><structfield>min_height</structfield></entry>
+ <entry>Minimum frame height, in pixels.</entry>
+ </row>
+ <row>
+ <entry>__u32</entry>
+ <entry><structfield>max_height</structfield></entry>
+ <entry>Maximum frame height, in pixels.</entry>
+ </row>
+ <row>
+ <entry>__u32</entry>
+ <entry><structfield>which</structfield></entry>
+ <entry>Frame sizes to be enumerated, from &v4l2-subdev-format-whence;.</entry>
+ </row>
+ <row>
+ <entry>__u32</entry>
+ <entry><structfield>reserved</structfield>[8]</entry>
+ <entry>Reserved for future extensions. Applications and drivers must
+ set the array to zero.</entry>
+ </row>
+ </tbody>
+ </tgroup>
+ </table>
+ </refsect1>
+
+ <refsect1>
+ &return-value;
+
+ <variablelist>
+ <varlistentry>
+ <term><errorcode>EINVAL</errorcode></term>
+ <listitem>
+ <para>The &v4l2-subdev-frame-size-enum; <structfield>pad</structfield>
+ references a non-existing pad, the <structfield>code</structfield> is
+ invalid for the given pad or the <structfield>index</structfield>
+ field is out of bounds.</para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
+ </refsect1>
+</refentry>
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