Markus Heiser | 5377d91 | 2016-06-30 15:18:56 +0200 | [diff] [blame] | 1 | .. -*- coding: utf-8; mode: rst -*- |
| 2 | |
| 3 | .. _vidioc-enuminput: |
| 4 | |
| 5 | ********************** |
| 6 | ioctl VIDIOC_ENUMINPUT |
| 7 | ********************** |
| 8 | |
| 9 | *man VIDIOC_ENUMINPUT(2)* |
| 10 | |
| 11 | Enumerate video inputs |
| 12 | |
| 13 | |
| 14 | Synopsis |
| 15 | ======== |
| 16 | |
| 17 | .. c:function:: int ioctl( int fd, int request, struct v4l2_input *argp ) |
| 18 | |
| 19 | Arguments |
| 20 | ========= |
| 21 | |
| 22 | ``fd`` |
| 23 | File descriptor returned by :ref:`open() <func-open>`. |
| 24 | |
| 25 | ``request`` |
| 26 | VIDIOC_ENUMINPUT |
| 27 | |
| 28 | ``argp`` |
| 29 | |
| 30 | |
| 31 | Description |
| 32 | =========== |
| 33 | |
| 34 | To query the attributes of a video input applications initialize the |
| 35 | ``index`` field of struct :ref:`v4l2_input <v4l2-input>` and call the |
| 36 | ``VIDIOC_ENUMINPUT`` ioctl with a pointer to this structure. Drivers |
| 37 | fill the rest of the structure or return an EINVAL error code when the |
| 38 | index is out of bounds. To enumerate all inputs applications shall begin |
| 39 | at index zero, incrementing by one until the driver returns EINVAL. |
| 40 | |
| 41 | |
| 42 | .. _v4l2-input: |
| 43 | |
| 44 | .. flat-table:: struct v4l2_input |
| 45 | :header-rows: 0 |
| 46 | :stub-columns: 0 |
| 47 | :widths: 1 1 2 |
| 48 | |
| 49 | |
| 50 | - .. row 1 |
| 51 | |
| 52 | - __u32 |
| 53 | |
| 54 | - ``index`` |
| 55 | |
| 56 | - Identifies the input, set by the application. |
| 57 | |
| 58 | - .. row 2 |
| 59 | |
| 60 | - __u8 |
| 61 | |
| 62 | - ``name``\ [32] |
| 63 | |
| 64 | - Name of the video input, a NUL-terminated ASCII string, for |
| 65 | example: "Vin (Composite 2)". This information is intended for the |
| 66 | user, preferably the connector label on the device itself. |
| 67 | |
| 68 | - .. row 3 |
| 69 | |
| 70 | - __u32 |
| 71 | |
| 72 | - ``type`` |
| 73 | |
| 74 | - Type of the input, see :ref:`input-type`. |
| 75 | |
| 76 | - .. row 4 |
| 77 | |
| 78 | - __u32 |
| 79 | |
| 80 | - ``audioset`` |
| 81 | |
| 82 | - Drivers can enumerate up to 32 video and audio inputs. This field |
| 83 | shows which audio inputs were selectable as audio source if this |
| 84 | was the currently selected video input. It is a bit mask. The LSB |
| 85 | corresponds to audio input 0, the MSB to input 31. Any number of |
| 86 | bits can be set, or none. |
| 87 | |
| 88 | When the driver does not enumerate audio inputs no bits must be |
| 89 | set. Applications shall not interpret this as lack of audio |
| 90 | support. Some drivers automatically select audio sources and do |
| 91 | not enumerate them since there is no choice anyway. |
| 92 | |
| 93 | For details on audio inputs and how to select the current input |
| 94 | see :ref:`audio`. |
| 95 | |
| 96 | - .. row 5 |
| 97 | |
| 98 | - __u32 |
| 99 | |
| 100 | - ``tuner`` |
| 101 | |
| 102 | - Capture devices can have zero or more tuners (RF demodulators). |
| 103 | When the ``type`` is set to ``V4L2_INPUT_TYPE_TUNER`` this is an |
| 104 | RF connector and this field identifies the tuner. It corresponds |
| 105 | to struct :ref:`v4l2_tuner <v4l2-tuner>` field ``index``. For |
| 106 | details on tuners see :ref:`tuner`. |
| 107 | |
| 108 | - .. row 6 |
| 109 | |
| 110 | - :ref:`v4l2_std_id <v4l2-std-id>` |
| 111 | |
| 112 | - ``std`` |
| 113 | |
| 114 | - Every video input supports one or more different video standards. |
| 115 | This field is a set of all supported standards. For details on |
| 116 | video standards and how to switch see :ref:`standard`. |
| 117 | |
| 118 | - .. row 7 |
| 119 | |
| 120 | - __u32 |
| 121 | |
| 122 | - ``status`` |
| 123 | |
| 124 | - This field provides status information about the input. See |
| 125 | :ref:`input-status` for flags. With the exception of the sensor |
| 126 | orientation bits ``status`` is only valid when this is the current |
| 127 | input. |
| 128 | |
| 129 | - .. row 8 |
| 130 | |
| 131 | - __u32 |
| 132 | |
| 133 | - ``capabilities`` |
| 134 | |
| 135 | - This field provides capabilities for the input. See |
| 136 | :ref:`input-capabilities` for flags. |
| 137 | |
| 138 | - .. row 9 |
| 139 | |
| 140 | - __u32 |
| 141 | |
| 142 | - ``reserved``\ [3] |
| 143 | |
| 144 | - Reserved for future extensions. Drivers must set the array to |
| 145 | zero. |
| 146 | |
| 147 | |
| 148 | |
| 149 | .. _input-type: |
| 150 | |
| 151 | .. flat-table:: Input Types |
| 152 | :header-rows: 0 |
| 153 | :stub-columns: 0 |
| 154 | :widths: 3 1 4 |
| 155 | |
| 156 | |
| 157 | - .. row 1 |
| 158 | |
| 159 | - ``V4L2_INPUT_TYPE_TUNER`` |
| 160 | |
| 161 | - 1 |
| 162 | |
| 163 | - This input uses a tuner (RF demodulator). |
| 164 | |
| 165 | - .. row 2 |
| 166 | |
| 167 | - ``V4L2_INPUT_TYPE_CAMERA`` |
| 168 | |
| 169 | - 2 |
| 170 | |
| 171 | - Analog baseband input, for example CVBS / Composite Video, |
| 172 | S-Video, RGB. |
| 173 | |
| 174 | |
| 175 | |
| 176 | .. _input-status: |
| 177 | |
| 178 | .. flat-table:: Input Status Flags |
| 179 | :header-rows: 0 |
| 180 | :stub-columns: 0 |
| 181 | |
| 182 | |
| 183 | - .. row 1 |
| 184 | |
| 185 | - :cspan:`2` General |
| 186 | |
| 187 | - .. row 2 |
| 188 | |
| 189 | - ``V4L2_IN_ST_NO_POWER`` |
| 190 | |
| 191 | - 0x00000001 |
| 192 | |
| 193 | - Attached device is off. |
| 194 | |
| 195 | - .. row 3 |
| 196 | |
| 197 | - ``V4L2_IN_ST_NO_SIGNAL`` |
| 198 | |
| 199 | - 0x00000002 |
| 200 | |
| 201 | - |
| 202 | |
| 203 | - .. row 4 |
| 204 | |
| 205 | - ``V4L2_IN_ST_NO_COLOR`` |
| 206 | |
| 207 | - 0x00000004 |
| 208 | |
| 209 | - The hardware supports color decoding, but does not detect color |
| 210 | modulation in the signal. |
| 211 | |
| 212 | - .. row 5 |
| 213 | |
| 214 | - :cspan:`2` Sensor Orientation |
| 215 | |
| 216 | - .. row 6 |
| 217 | |
| 218 | - ``V4L2_IN_ST_HFLIP`` |
| 219 | |
| 220 | - 0x00000010 |
| 221 | |
| 222 | - The input is connected to a device that produces a signal that is |
| 223 | flipped horizontally and does not correct this before passing the |
| 224 | signal to userspace. |
| 225 | |
| 226 | - .. row 7 |
| 227 | |
| 228 | - ``V4L2_IN_ST_VFLIP`` |
| 229 | |
| 230 | - 0x00000020 |
| 231 | |
| 232 | - The input is connected to a device that produces a signal that is |
| 233 | flipped vertically and does not correct this before passing the |
| 234 | signal to userspace. Note that a 180 degree rotation is the same |
| 235 | as HFLIP | VFLIP |
| 236 | |
| 237 | - .. row 8 |
| 238 | |
| 239 | - :cspan:`2` Analog Video |
| 240 | |
| 241 | - .. row 9 |
| 242 | |
| 243 | - ``V4L2_IN_ST_NO_H_LOCK`` |
| 244 | |
| 245 | - 0x00000100 |
| 246 | |
| 247 | - No horizontal sync lock. |
| 248 | |
| 249 | - .. row 10 |
| 250 | |
| 251 | - ``V4L2_IN_ST_COLOR_KILL`` |
| 252 | |
| 253 | - 0x00000200 |
| 254 | |
| 255 | - A color killer circuit automatically disables color decoding when |
| 256 | it detects no color modulation. When this flag is set the color |
| 257 | killer is enabled *and* has shut off color decoding. |
| 258 | |
| 259 | - .. row 11 |
| 260 | |
| 261 | - :cspan:`2` Digital Video |
| 262 | |
| 263 | - .. row 12 |
| 264 | |
| 265 | - ``V4L2_IN_ST_NO_SYNC`` |
| 266 | |
| 267 | - 0x00010000 |
| 268 | |
| 269 | - No synchronization lock. |
| 270 | |
| 271 | - .. row 13 |
| 272 | |
| 273 | - ``V4L2_IN_ST_NO_EQU`` |
| 274 | |
| 275 | - 0x00020000 |
| 276 | |
| 277 | - No equalizer lock. |
| 278 | |
| 279 | - .. row 14 |
| 280 | |
| 281 | - ``V4L2_IN_ST_NO_CARRIER`` |
| 282 | |
| 283 | - 0x00040000 |
| 284 | |
| 285 | - Carrier recovery failed. |
| 286 | |
| 287 | - .. row 15 |
| 288 | |
| 289 | - :cspan:`2` VCR and Set-Top Box |
| 290 | |
| 291 | - .. row 16 |
| 292 | |
| 293 | - ``V4L2_IN_ST_MACROVISION`` |
| 294 | |
| 295 | - 0x01000000 |
| 296 | |
| 297 | - Macrovision is an analog copy prevention system mangling the video |
| 298 | signal to confuse video recorders. When this flag is set |
| 299 | Macrovision has been detected. |
| 300 | |
| 301 | - .. row 17 |
| 302 | |
| 303 | - ``V4L2_IN_ST_NO_ACCESS`` |
| 304 | |
| 305 | - 0x02000000 |
| 306 | |
| 307 | - Conditional access denied. |
| 308 | |
| 309 | - .. row 18 |
| 310 | |
| 311 | - ``V4L2_IN_ST_VTR`` |
| 312 | |
| 313 | - 0x04000000 |
| 314 | |
| 315 | - VTR time constant. [?] |
| 316 | |
| 317 | |
| 318 | |
| 319 | .. _input-capabilities: |
| 320 | |
| 321 | .. flat-table:: Input capabilities |
| 322 | :header-rows: 0 |
| 323 | :stub-columns: 0 |
| 324 | :widths: 3 1 4 |
| 325 | |
| 326 | |
| 327 | - .. row 1 |
| 328 | |
| 329 | - ``V4L2_IN_CAP_DV_TIMINGS`` |
| 330 | |
| 331 | - 0x00000002 |
| 332 | |
| 333 | - This input supports setting video timings by using |
| 334 | VIDIOC_S_DV_TIMINGS. |
| 335 | |
| 336 | - .. row 2 |
| 337 | |
| 338 | - ``V4L2_IN_CAP_STD`` |
| 339 | |
| 340 | - 0x00000004 |
| 341 | |
| 342 | - This input supports setting the TV standard by using |
| 343 | VIDIOC_S_STD. |
| 344 | |
| 345 | - .. row 3 |
| 346 | |
| 347 | - ``V4L2_IN_CAP_NATIVE_SIZE`` |
| 348 | |
| 349 | - 0x00000008 |
| 350 | |
| 351 | - This input supports setting the native size using the |
| 352 | ``V4L2_SEL_TGT_NATIVE_SIZE`` selection target, see |
| 353 | :ref:`v4l2-selections-common`. |
| 354 | |
| 355 | |
| 356 | |
| 357 | Return Value |
| 358 | ============ |
| 359 | |
| 360 | On success 0 is returned, on error -1 and the ``errno`` variable is set |
| 361 | appropriately. The generic error codes are described at the |
| 362 | :ref:`Generic Error Codes <gen-errors>` chapter. |
| 363 | |
| 364 | EINVAL |
| 365 | The struct :ref:`v4l2_input <v4l2-input>` ``index`` is out of |
| 366 | bounds. |
| 367 | |
| 368 | |
| 369 | .. ------------------------------------------------------------------------------ |
| 370 | .. This file was automatically converted from DocBook-XML with the dbxml |
| 371 | .. library (https://github.com/return42/sphkerneldoc). The origin XML comes |
| 372 | .. from the linux kernel, refer to: |
| 373 | .. |
| 374 | .. * https://github.com/torvalds/linux/tree/master/Documentation/DocBook |
| 375 | .. ------------------------------------------------------------------------------ |