| .. -*- coding: utf-8; mode: rst -*- |
| |
| .. _VIDIOC_ENUMINPUT: |
| |
| ********************** |
| ioctl VIDIOC_ENUMINPUT |
| ********************** |
| |
| Name |
| ==== |
| |
| VIDIOC_ENUMINPUT - Enumerate video inputs |
| |
| |
| Synopsis |
| ======== |
| |
| .. c:function:: int ioctl( int fd, VIDIOC_ENUMINPUT, struct v4l2_input *argp ) |
| :name: VIDIOC_ENUMINPUT |
| |
| |
| Arguments |
| ========= |
| |
| ``fd`` |
| File descriptor returned by :ref:`open() <func-open>`. |
| |
| ``argp`` |
| Pointer to struct :c:type:`v4l2_input`. |
| |
| |
| Description |
| =========== |
| |
| To query the attributes of a video input applications initialize the |
| ``index`` field of struct :c:type:`v4l2_input` and call the |
| :ref:`VIDIOC_ENUMINPUT` with a pointer to this structure. Drivers |
| fill the rest of the structure or return an ``EINVAL`` error code when the |
| index is out of bounds. To enumerate all inputs applications shall begin |
| at index zero, incrementing by one until the driver returns ``EINVAL``. |
| |
| |
| .. tabularcolumns:: |p{4.4cm}|p{4.4cm}|p{8.7cm}| |
| |
| .. c:type:: v4l2_input |
| |
| .. flat-table:: struct v4l2_input |
| :header-rows: 0 |
| :stub-columns: 0 |
| :widths: 1 1 2 |
| |
| * - __u32 |
| - ``index`` |
| - Identifies the input, set by the application. |
| * - __u8 |
| - ``name``\ [32] |
| - Name of the video input, a NUL-terminated ASCII string, for |
| example: "Vin (Composite 2)". This information is intended for the |
| user, preferably the connector label on the device itself. |
| * - __u32 |
| - ``type`` |
| - Type of the input, see :ref:`input-type`. |
| * - __u32 |
| - ``audioset`` |
| - Drivers can enumerate up to 32 video and audio inputs. This field |
| shows which audio inputs were selectable as audio source if this |
| was the currently selected video input. It is a bit mask. The LSB |
| corresponds to audio input 0, the MSB to input 31. Any number of |
| bits can be set, or none. |
| |
| When the driver does not enumerate audio inputs no bits must be |
| set. Applications shall not interpret this as lack of audio |
| support. Some drivers automatically select audio sources and do |
| not enumerate them since there is no choice anyway. |
| |
| For details on audio inputs and how to select the current input |
| see :ref:`audio`. |
| * - __u32 |
| - ``tuner`` |
| - Capture devices can have zero or more tuners (RF demodulators). |
| When the ``type`` is set to ``V4L2_INPUT_TYPE_TUNER`` this is an |
| RF connector and this field identifies the tuner. It corresponds |
| to struct :c:type:`v4l2_tuner` field ``index``. For |
| details on tuners see :ref:`tuner`. |
| * - :ref:`v4l2_std_id <v4l2-std-id>` |
| - ``std`` |
| - Every video input supports one or more different video standards. |
| This field is a set of all supported standards. For details on |
| video standards and how to switch see :ref:`standard`. |
| * - __u32 |
| - ``status`` |
| - This field provides status information about the input. See |
| :ref:`input-status` for flags. With the exception of the sensor |
| orientation bits ``status`` is only valid when this is the current |
| input. |
| * - __u32 |
| - ``capabilities`` |
| - This field provides capabilities for the input. See |
| :ref:`input-capabilities` for flags. |
| * - __u32 |
| - ``reserved``\ [3] |
| - Reserved for future extensions. Drivers must set the array to |
| zero. |
| |
| |
| |
| .. tabularcolumns:: |p{6.6cm}|p{2.2cm}|p{8.7cm}| |
| |
| .. _input-type: |
| |
| .. flat-table:: Input Types |
| :header-rows: 0 |
| :stub-columns: 0 |
| :widths: 3 1 4 |
| |
| * - ``V4L2_INPUT_TYPE_TUNER`` |
| - 1 |
| - This input uses a tuner (RF demodulator). |
| * - ``V4L2_INPUT_TYPE_CAMERA`` |
| - 2 |
| - Any non-tuner video input, for example Composite Video, |
| S-Video, HDMI, camera sensor. The naming as ``_TYPE_CAMERA`` is historical, |
| today we would have called it ``_TYPE_VIDEO``. |
| * - ``V4L2_INPUT_TYPE_TOUCH`` |
| - 3 |
| - This input is a touch device for capturing raw touch data. |
| |
| |
| |
| .. tabularcolumns:: |p{4.8cm}|p{2.6cm}|p{10.1cm}| |
| |
| .. _input-status: |
| |
| .. flat-table:: Input Status Flags |
| :header-rows: 0 |
| :stub-columns: 0 |
| |
| * - :cspan:`2` General |
| * - ``V4L2_IN_ST_NO_POWER`` |
| - 0x00000001 |
| - Attached device is off. |
| * - ``V4L2_IN_ST_NO_SIGNAL`` |
| - 0x00000002 |
| - |
| * - ``V4L2_IN_ST_NO_COLOR`` |
| - 0x00000004 |
| - The hardware supports color decoding, but does not detect color |
| modulation in the signal. |
| * - :cspan:`2` Sensor Orientation |
| * - ``V4L2_IN_ST_HFLIP`` |
| - 0x00000010 |
| - The input is connected to a device that produces a signal that is |
| flipped horizontally and does not correct this before passing the |
| signal to userspace. |
| * - ``V4L2_IN_ST_VFLIP`` |
| - 0x00000020 |
| - The input is connected to a device that produces a signal that is |
| flipped vertically and does not correct this before passing the |
| signal to userspace. |
| .. note:: A 180 degree rotation is the same as HFLIP | VFLIP |
| * - :cspan:`2` Analog Video |
| * - ``V4L2_IN_ST_NO_H_LOCK`` |
| - 0x00000100 |
| - No horizontal sync lock. |
| * - ``V4L2_IN_ST_COLOR_KILL`` |
| - 0x00000200 |
| - A color killer circuit automatically disables color decoding when |
| it detects no color modulation. When this flag is set the color |
| killer is enabled *and* has shut off color decoding. |
| * - ``V4L2_IN_ST_NO_V_LOCK`` |
| - 0x00000400 |
| - No vertical sync lock. |
| * - ``V4L2_IN_ST_NO_STD_LOCK`` |
| - 0x00000800 |
| - No standard format lock in case of auto-detection format |
| by the component. |
| * - :cspan:`2` Digital Video |
| * - ``V4L2_IN_ST_NO_SYNC`` |
| - 0x00010000 |
| - No synchronization lock. |
| * - ``V4L2_IN_ST_NO_EQU`` |
| - 0x00020000 |
| - No equalizer lock. |
| * - ``V4L2_IN_ST_NO_CARRIER`` |
| - 0x00040000 |
| - Carrier recovery failed. |
| * - :cspan:`2` VCR and Set-Top Box |
| * - ``V4L2_IN_ST_MACROVISION`` |
| - 0x01000000 |
| - Macrovision is an analog copy prevention system mangling the video |
| signal to confuse video recorders. When this flag is set |
| Macrovision has been detected. |
| * - ``V4L2_IN_ST_NO_ACCESS`` |
| - 0x02000000 |
| - Conditional access denied. |
| * - ``V4L2_IN_ST_VTR`` |
| - 0x04000000 |
| - VTR time constant. [?] |
| |
| |
| |
| .. tabularcolumns:: |p{6.6cm}|p{2.2cm}|p{8.7cm}| |
| |
| .. _input-capabilities: |
| |
| .. flat-table:: Input capabilities |
| :header-rows: 0 |
| :stub-columns: 0 |
| :widths: 3 1 4 |
| |
| * - ``V4L2_IN_CAP_DV_TIMINGS`` |
| - 0x00000002 |
| - This input supports setting video timings by using |
| ``VIDIOC_S_DV_TIMINGS``. |
| * - ``V4L2_IN_CAP_STD`` |
| - 0x00000004 |
| - This input supports setting the TV standard by using |
| ``VIDIOC_S_STD``. |
| * - ``V4L2_IN_CAP_NATIVE_SIZE`` |
| - 0x00000008 |
| - This input supports setting the native size using the |
| ``V4L2_SEL_TGT_NATIVE_SIZE`` selection target, see |
| :ref:`v4l2-selections-common`. |
| |
| |
| Return Value |
| ============ |
| |
| On success 0 is returned, on error -1 and the ``errno`` variable is set |
| appropriately. The generic error codes are described at the |
| :ref:`Generic Error Codes <gen-errors>` chapter. |
| |
| EINVAL |
| The struct :c:type:`v4l2_input` ``index`` is out of |
| bounds. |
