1<refentry id="vidioc-enuminput"> 2 <refmeta> 3 <refentrytitle>ioctl VIDIOC_ENUMINPUT</refentrytitle> 4 &manvol; 5 </refmeta> 6 7 <refnamediv> 8 <refname>VIDIOC_ENUMINPUT</refname> 9 <refpurpose>Enumerate video inputs</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_input 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_ENUMINPUT</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 <para>To query the attributes of a video input applications 53initialize the <structfield>index</structfield> field of &v4l2-input; 54and call the <constant>VIDIOC_ENUMINPUT</constant> ioctl with a 55pointer to this structure. Drivers fill the rest of the structure or 56return an &EINVAL; when the index is out of bounds. To enumerate all 57inputs applications shall begin at index zero, incrementing by one 58until the driver returns <errorcode>EINVAL</errorcode>.</para> 59 60 <table frame="none" pgwide="1" id="v4l2-input"> 61 <title>struct <structname>v4l2_input</structname></title> 62 <tgroup cols="3"> 63 &cs-str; 64 <tbody valign="top"> 65 <row> 66 <entry>__u32</entry> 67 <entry><structfield>index</structfield></entry> 68 <entry>Identifies the input, set by the 69application.</entry> 70 </row> 71 <row> 72 <entry>__u8</entry> 73 <entry><structfield>name</structfield>[32]</entry> 74 <entry>Name of the video input, a NUL-terminated ASCII 75string, for example: "Vin (Composite 2)". This information is intended 76for the user, preferably the connector label on the device itself.</entry> 77 </row> 78 <row> 79 <entry>__u32</entry> 80 <entry><structfield>type</structfield></entry> 81 <entry>Type of the input, see <xref 82 linkend="input-type" />.</entry> 83 </row> 84 <row> 85 <entry>__u32</entry> 86 <entry><structfield>audioset</structfield></entry> 87 <entry><para>Drivers can enumerate up to 32 video and 88audio inputs. This field shows which audio inputs were selectable as 89audio source if this was the currently selected video input. It is a 90bit mask. The LSB corresponds to audio input 0, the MSB to input 31. 91Any number of bits can be set, or none.</para><para>When the driver 92does not enumerate audio inputs no bits must be set. Applications 93shall not interpret this as lack of audio support. Some drivers 94automatically select audio sources and do not enumerate them since 95there is no choice anyway.</para><para>For details on audio inputs and 96how to select the current input see <xref 97 linkend="audio" />.</para></entry> 98 </row> 99 <row> 100 <entry>__u32</entry> 101 <entry><structfield>tuner</structfield></entry> 102 <entry>Capture devices can have zero or more tuners (RF 103demodulators). When the <structfield>type</structfield> is set to 104<constant>V4L2_INPUT_TYPE_TUNER</constant> this is an RF connector and 105this field identifies the tuner. It corresponds to 106&v4l2-tuner; field <structfield>index</structfield>. For details on 107tuners see <xref linkend="tuner" />.</entry> 108 </row> 109 <row> 110 <entry>&v4l2-std-id;</entry> 111 <entry><structfield>std</structfield></entry> 112 <entry>Every video input supports one or more different 113video standards. This field is a set of all supported standards. For 114details on video standards and how to switch see <xref 115linkend="standard" />.</entry> 116 </row> 117 <row> 118 <entry>__u32</entry> 119 <entry><structfield>status</structfield></entry> 120 <entry>This field provides status information about the 121input. See <xref linkend="input-status" /> for flags. 122With the exception of the sensor orientation bits <structfield>status</structfield> is only valid when this is the 123current input.</entry> 124 </row> 125 <row> 126 <entry>__u32</entry> 127 <entry><structfield>capabilities</structfield></entry> 128 <entry>This field provides capabilities for the 129input. See <xref linkend="input-capabilities" /> for flags.</entry> 130 </row> 131 <row> 132 <entry>__u32</entry> 133 <entry><structfield>reserved</structfield>[3]</entry> 134 <entry>Reserved for future extensions. Drivers must set 135the array to zero.</entry> 136 </row> 137 </tbody> 138 </tgroup> 139 </table> 140 141 <table frame="none" pgwide="1" id="input-type"> 142 <title>Input Types</title> 143 <tgroup cols="3"> 144 &cs-def; 145 <tbody valign="top"> 146 <row> 147 <entry><constant>V4L2_INPUT_TYPE_TUNER</constant></entry> 148 <entry>1</entry> 149 <entry>This input uses a tuner (RF demodulator).</entry> 150 </row> 151 <row> 152 <entry><constant>V4L2_INPUT_TYPE_CAMERA</constant></entry> 153 <entry>2</entry> 154 <entry>Analog baseband input, for example CVBS / 155Composite Video, S-Video, RGB.</entry> 156 </row> 157 </tbody> 158 </tgroup> 159 </table> 160 161 <!-- Status flags based on proposal by Mark McClelland, 162video4linux-list@redhat.com on 18 Oct 2002, subject "Re: [V4L] Re: 163v4l2 api". "Why are some of them inverted? So that the driver doesn't 164have to lie about the status in cases where it can't tell one way or 165the other. Plus, a status of zero would generally mean that everything 166is OK." --> 167 168 <table frame="none" pgwide="1" id="input-status"> 169 <title>Input Status Flags</title> 170 <tgroup cols="3"> 171 <colspec colname="c1" /> 172 <colspec colname="c2" align="center" /> 173 <colspec colname="c3" /> 174 <spanspec namest="c1" nameend="c3" spanname="hspan" 175 align="left" /> 176 <tbody valign="top"> 177 <row> 178 <entry spanname="hspan">General</entry> 179 </row> 180 <row> 181 <entry><constant>V4L2_IN_ST_NO_POWER</constant></entry> 182 <entry>0x00000001</entry> 183 <entry>Attached device is off.</entry> 184 </row> 185 <row> 186 <entry><constant>V4L2_IN_ST_NO_SIGNAL</constant></entry> 187 <entry>0x00000002</entry> 188 <entry></entry> 189 </row> 190 <row> 191 <entry><constant>V4L2_IN_ST_NO_COLOR</constant></entry> 192 <entry>0x00000004</entry> 193 <entry>The hardware supports color decoding, but does not 194detect color modulation in the signal.</entry> 195 </row> 196 <row> 197 <entry spanname="hspan">Sensor Orientation</entry> 198 </row> 199 <row> 200 <entry><constant>V4L2_IN_ST_HFLIP</constant></entry> 201 <entry>0x00000010</entry> 202 <entry>The input is connected to a device that produces a signal 203that is flipped horizontally and does not correct this before passing the 204signal to userspace.</entry> 205 </row> 206 <row> 207 <entry><constant>V4L2_IN_ST_VFLIP</constant></entry> 208 <entry>0x00000020</entry> 209 <entry>The input is connected to a device that produces a signal 210that is flipped vertically and does not correct this before passing the 211signal to userspace. Note that a 180 degree rotation is the same as HFLIP | VFLIP</entry> 212 </row> 213 <row> 214 <entry spanname="hspan">Analog Video</entry> 215 </row> 216 <row> 217 <entry><constant>V4L2_IN_ST_NO_H_LOCK</constant></entry> 218 <entry>0x00000100</entry> 219 <entry>No horizontal sync lock.</entry> 220 </row> 221 <row> 222 <entry><constant>V4L2_IN_ST_COLOR_KILL</constant></entry> 223 <entry>0x00000200</entry> 224 <entry>A color killer circuit automatically disables color 225decoding when it detects no color modulation. When this flag is set 226the color killer is enabled <emphasis>and</emphasis> has shut off 227color decoding.</entry> 228 </row> 229 <row> 230 <entry spanname="hspan">Digital Video</entry> 231 </row> 232 <row> 233 <entry><constant>V4L2_IN_ST_NO_SYNC</constant></entry> 234 <entry>0x00010000</entry> 235 <entry>No synchronization lock.</entry> 236 </row> 237 <row> 238 <entry><constant>V4L2_IN_ST_NO_EQU</constant></entry> 239 <entry>0x00020000</entry> 240 <entry>No equalizer lock.</entry> 241 </row> 242 <row> 243 <entry><constant>V4L2_IN_ST_NO_CARRIER</constant></entry> 244 <entry>0x00040000</entry> 245 <entry>Carrier recovery failed.</entry> 246 </row> 247 <row> 248 <entry spanname="hspan">VCR and Set-Top Box</entry> 249 </row> 250 <row> 251 <entry><constant>V4L2_IN_ST_MACROVISION</constant></entry> 252 <entry>0x01000000</entry> 253 <entry>Macrovision is an analog copy prevention system 254mangling the video signal to confuse video recorders. When this 255flag is set Macrovision has been detected.</entry> 256 </row> 257 <row> 258 <entry><constant>V4L2_IN_ST_NO_ACCESS</constant></entry> 259 <entry>0x02000000</entry> 260 <entry>Conditional access denied.</entry> 261 </row> 262 <row> 263 <entry><constant>V4L2_IN_ST_VTR</constant></entry> 264 <entry>0x04000000</entry> 265 <entry>VTR time constant. [?]</entry> 266 </row> 267 </tbody> 268 </tgroup> 269 </table> 270 271 <!-- Capability flags based on video timings RFC by Muralidharan 272Karicheri, titled RFC (v1.2): V4L - Support for video timings at the 273input/output interface to linux-media@vger.kernel.org on 19 Oct 2009. 274 --> 275 <table frame="none" pgwide="1" id="input-capabilities"> 276 <title>Input capabilities</title> 277 <tgroup cols="3"> 278 &cs-def; 279 <tbody valign="top"> 280 <row> 281 <entry><constant>V4L2_IN_CAP_PRESETS</constant></entry> 282 <entry>0x00000001</entry> 283 <entry>This input supports setting DV presets by using VIDIOC_S_DV_PRESET.</entry> 284 </row> 285 <row> 286 <entry><constant>V4L2_IN_CAP_CUSTOM_TIMINGS</constant></entry> 287 <entry>0x00000002</entry> 288 <entry>This input supports setting custom video timings by using VIDIOC_S_DV_TIMINGS.</entry> 289 </row> 290 <row> 291 <entry><constant>V4L2_IN_CAP_STD</constant></entry> 292 <entry>0x00000004</entry> 293 <entry>This input supports setting the TV standard by using VIDIOC_S_STD.</entry> 294 </row> 295 </tbody> 296 </tgroup> 297 </table> 298 </refsect1> 299 300 <refsect1> 301 &return-value; 302 303 <variablelist> 304 <varlistentry> 305 <term><errorcode>EINVAL</errorcode></term> 306 <listitem> 307 <para>The &v4l2-input; <structfield>index</structfield> is 308out of bounds.</para> 309 </listitem> 310 </varlistentry> 311 </variablelist> 312 </refsect1> 313</refentry> 314 315<!-- 316Local Variables: 317mode: sgml 318sgml-parent-document: "v4l2.sgml" 319indent-tabs-mode: nil 320End: 321--> 322