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Diffstat (limited to 'Documentation/DocBook/media/v4l/vidioc-subdev-enum-frame-size.xml')
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diff --git a/Documentation/DocBook/media/v4l/vidioc-subdev-enum-frame-size.xml b/Documentation/DocBook/media/v4l/vidioc-subdev-enum-frame-size.xml new file mode 100644 index 000000000000..79ce42b7c60c --- /dev/null +++ b/Documentation/DocBook/media/v4l/vidioc-subdev-enum-frame-size.xml | |||
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1 | <refentry id="vidioc-subdev-enum-frame-size"> | ||
2 | <refmeta> | ||
3 | <refentrytitle>ioctl VIDIOC_SUBDEV_ENUM_FRAME_SIZE</refentrytitle> | ||
4 | &manvol; | ||
5 | </refmeta> | ||
6 | |||
7 | <refnamediv> | ||
8 | <refname>VIDIOC_SUBDEV_ENUM_FRAME_SIZE</refname> | ||
9 | <refpurpose>Enumerate media bus frame sizes</refpurpose> | ||
10 | </refnamediv> | ||
11 | |||
12 | <refsynopsisdiv> | ||
13 | <funcsynopsis> | ||
14 | <funcprototype> | ||
15 | <funcdef>int <function>ioctl</function></funcdef> | ||
16 | <paramdef>int <parameter>fd</parameter></paramdef> | ||
17 | <paramdef>int <parameter>request</parameter></paramdef> | ||
18 | <paramdef>struct v4l2_subdev_frame_size_enum * | ||
19 | <parameter>argp</parameter></paramdef> | ||
20 | </funcprototype> | ||
21 | </funcsynopsis> | ||
22 | </refsynopsisdiv> | ||
23 | |||
24 | <refsect1> | ||
25 | <title>Arguments</title> | ||
26 | |||
27 | <variablelist> | ||
28 | <varlistentry> | ||
29 | <term><parameter>fd</parameter></term> | ||
30 | <listitem> | ||
31 | <para>&fd;</para> | ||
32 | </listitem> | ||
33 | </varlistentry> | ||
34 | <varlistentry> | ||
35 | <term><parameter>request</parameter></term> | ||
36 | <listitem> | ||
37 | <para>VIDIOC_SUBDEV_ENUM_FRAME_SIZE</para> | ||
38 | </listitem> | ||
39 | </varlistentry> | ||
40 | <varlistentry> | ||
41 | <term><parameter>argp</parameter></term> | ||
42 | <listitem> | ||
43 | <para></para> | ||
44 | </listitem> | ||
45 | </varlistentry> | ||
46 | </variablelist> | ||
47 | </refsect1> | ||
48 | |||
49 | <refsect1> | ||
50 | <title>Description</title> | ||
51 | |||
52 | <note> | ||
53 | <title>Experimental</title> | ||
54 | <para>This is an <link linkend="experimental">experimental</link> | ||
55 | interface and may change in the future.</para> | ||
56 | </note> | ||
57 | |||
58 | <para>This ioctl allows applications to enumerate all frame sizes | ||
59 | supported by a sub-device on the given pad for the given media bus format. | ||
60 | Supported formats can be retrieved with the &VIDIOC-SUBDEV-ENUM-MBUS-CODE; | ||
61 | ioctl.</para> | ||
62 | |||
63 | <para>To enumerate frame sizes applications initialize the | ||
64 | <structfield>pad</structfield>, <structfield>code</structfield> and | ||
65 | <structfield>index</structfield> fields of the | ||
66 | &v4l2-subdev-mbus-code-enum; and call the | ||
67 | <constant>VIDIOC_SUBDEV_ENUM_FRAME_SIZE</constant> ioctl with a pointer to | ||
68 | the structure. Drivers fill the minimum and maximum frame sizes or return | ||
69 | an &EINVAL; if one of the input parameters is invalid.</para> | ||
70 | |||
71 | <para>Sub-devices that only support discrete frame sizes (such as most | ||
72 | sensors) will return one or more frame sizes with identical minimum and | ||
73 | maximum values.</para> | ||
74 | |||
75 | <para>Not all possible sizes in given [minimum, maximum] ranges need to be | ||
76 | supported. For instance, a scaler that uses a fixed-point scaling ratio | ||
77 | might not be able to produce every frame size between the minimum and | ||
78 | maximum values. Applications must use the &VIDIOC-SUBDEV-S-FMT; ioctl to | ||
79 | try the sub-device for an exact supported frame size.</para> | ||
80 | |||
81 | <para>Available frame sizes may depend on the current 'try' formats at other | ||
82 | pads of the sub-device, as well as on the current active links and the | ||
83 | current values of V4L2 controls. See &VIDIOC-SUBDEV-G-FMT; for more | ||
84 | information about try formats.</para> | ||
85 | |||
86 | <table pgwide="1" frame="none" id="v4l2-subdev-frame-size-enum"> | ||
87 | <title>struct <structname>v4l2_subdev_frame_size_enum</structname></title> | ||
88 | <tgroup cols="3"> | ||
89 | &cs-str; | ||
90 | <tbody valign="top"> | ||
91 | <row> | ||
92 | <entry>__u32</entry> | ||
93 | <entry><structfield>index</structfield></entry> | ||
94 | <entry>Number of the format in the enumeration, set by the | ||
95 | application.</entry> | ||
96 | </row> | ||
97 | <row> | ||
98 | <entry>__u32</entry> | ||
99 | <entry><structfield>pad</structfield></entry> | ||
100 | <entry>Pad number as reported by the media controller API.</entry> | ||
101 | </row> | ||
102 | <row> | ||
103 | <entry>__u32</entry> | ||
104 | <entry><structfield>code</structfield></entry> | ||
105 | <entry>The media bus format code, as defined in | ||
106 | <xref linkend="v4l2-mbus-format" />.</entry> | ||
107 | </row> | ||
108 | <row> | ||
109 | <entry>__u32</entry> | ||
110 | <entry><structfield>min_width</structfield></entry> | ||
111 | <entry>Minimum frame width, in pixels.</entry> | ||
112 | </row> | ||
113 | <row> | ||
114 | <entry>__u32</entry> | ||
115 | <entry><structfield>max_width</structfield></entry> | ||
116 | <entry>Maximum frame width, in pixels.</entry> | ||
117 | </row> | ||
118 | <row> | ||
119 | <entry>__u32</entry> | ||
120 | <entry><structfield>min_height</structfield></entry> | ||
121 | <entry>Minimum frame height, in pixels.</entry> | ||
122 | </row> | ||
123 | <row> | ||
124 | <entry>__u32</entry> | ||
125 | <entry><structfield>max_height</structfield></entry> | ||
126 | <entry>Maximum frame height, in pixels.</entry> | ||
127 | </row> | ||
128 | <row> | ||
129 | <entry>__u32</entry> | ||
130 | <entry><structfield>reserved</structfield>[9]</entry> | ||
131 | <entry>Reserved for future extensions. Applications and drivers must | ||
132 | set the array to zero.</entry> | ||
133 | </row> | ||
134 | </tbody> | ||
135 | </tgroup> | ||
136 | </table> | ||
137 | </refsect1> | ||
138 | |||
139 | <refsect1> | ||
140 | &return-value; | ||
141 | |||
142 | <variablelist> | ||
143 | <varlistentry> | ||
144 | <term><errorcode>EINVAL</errorcode></term> | ||
145 | <listitem> | ||
146 | <para>The &v4l2-subdev-frame-size-enum; <structfield>pad</structfield> | ||
147 | references a non-existing pad, the <structfield>code</structfield> is | ||
148 | invalid for the given pad or the <structfield>index</structfield> | ||
149 | field is out of bounds.</para> | ||
150 | </listitem> | ||
151 | </varlistentry> | ||
152 | </variablelist> | ||
153 | </refsect1> | ||
154 | </refentry> | ||