1.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
2
3.. _VIDIOC_SUBDEV_ENUM_MBUS_CODE:
4
5**********************************
6ioctl VIDIOC_SUBDEV_ENUM_MBUS_CODE
7**********************************
8
9Name
10====
11
12VIDIOC_SUBDEV_ENUM_MBUS_CODE - Enumerate media bus formats
13
14
15Synopsis
16========
17
18.. c:function:: int ioctl( int fd, VIDIOC_SUBDEV_ENUM_MBUS_CODE, struct v4l2_subdev_mbus_code_enum * argp )
19    :name: VIDIOC_SUBDEV_ENUM_MBUS_CODE
20
21
22Arguments
23=========
24
25``fd``
26    File descriptor returned by :ref:`open() <func-open>`.
27
28``argp``
29    Pointer to struct :c:type:`v4l2_subdev_mbus_code_enum`.
30
31
32Description
33===========
34
35To enumerate media bus formats available at a given sub-device pad
36applications initialize the ``pad``, ``which`` and ``index`` fields of
37struct
38:c:type:`v4l2_subdev_mbus_code_enum` and
39call the :ref:`VIDIOC_SUBDEV_ENUM_MBUS_CODE` ioctl with a pointer to this
40structure. Drivers fill the rest of the structure or return an ``EINVAL``
41error code if either the ``pad`` or ``index`` are invalid. All media bus
42formats are enumerable by beginning at index zero and incrementing by
43one until ``EINVAL`` is returned.
44
45Available media bus formats may depend on the current 'try' formats at
46other pads of the sub-device, as well as on the current active links.
47See :ref:`VIDIOC_SUBDEV_G_FMT` for more
48information about the try formats.
49
50
51.. c:type:: v4l2_subdev_mbus_code_enum
52
53.. tabularcolumns:: |p{4.4cm}|p{4.4cm}|p{8.7cm}|
54
55.. flat-table:: struct v4l2_subdev_mbus_code_enum
56    :header-rows:  0
57    :stub-columns: 0
58    :widths:       1 1 2
59
60    * - __u32
61      - ``pad``
62      - Pad number as reported by the media controller API.
63    * - __u32
64      - ``index``
65      - Number of the format in the enumeration, set by the application.
66    * - __u32
67      - ``code``
68      - The media bus format code, as defined in
69	:ref:`v4l2-mbus-format`.
70    * - __u32
71      - ``which``
72      - Media bus format codes to be enumerated, from enum
73	:ref:`v4l2_subdev_format_whence <v4l2-subdev-format-whence>`.
74    * - __u32
75      - ``flags``
76      - See :ref:`v4l2-subdev-mbus-code-flags`
77    * - __u32
78      - ``reserved``\ [7]
79      - Reserved for future extensions. Applications and drivers must set
80	the array to zero.
81
82
83
84.. tabularcolumns:: |p{4.4cm}|p{4.4cm}|p{7.7cm}|
85
86.. _v4l2-subdev-mbus-code-flags:
87
88.. flat-table:: Subdev Media Bus Code Enumerate Flags
89    :header-rows:  0
90    :stub-columns: 0
91    :widths:       1 1 2
92
93    * - V4L2_SUBDEV_MBUS_CODE_CSC_COLORSPACE
94      - 0x00000001
95      - The driver allows the application to try to change the default colorspace
96	encoding. The application can ask to configure the colorspace of the
97	subdevice when calling the :ref:`VIDIOC_SUBDEV_S_FMT <VIDIOC_SUBDEV_G_FMT>`
98	ioctl with :ref:`V4L2_MBUS_FRAMEFMT_SET_CSC <mbus-framefmt-set-csc>` set.
99	See :ref:`v4l2-mbus-format` on how to do this.
100    * - V4L2_SUBDEV_MBUS_CODE_CSC_XFER_FUNC
101      - 0x00000002
102      - The driver allows the application to try to change the default transform function.
103	The application can ask to configure the transform function of
104	the subdevice when calling the :ref:`VIDIOC_SUBDEV_S_FMT <VIDIOC_SUBDEV_G_FMT>`
105	ioctl with :ref:`V4L2_MBUS_FRAMEFMT_SET_CSC <mbus-framefmt-set-csc>` set.
106	See :ref:`v4l2-mbus-format` on how to do this.
107    * - V4L2_SUBDEV_MBUS_CODE_CSC_YCBCR_ENC
108      - 0x00000004
109      - The driver allows the application to try to change the default Y'CbCr
110	encoding. The application can ask to configure the Y'CbCr encoding of the
111	subdevice when calling the :ref:`VIDIOC_SUBDEV_S_FMT <VIDIOC_SUBDEV_G_FMT>`
112	ioctl with :ref:`V4L2_MBUS_FRAMEFMT_SET_CSC <mbus-framefmt-set-csc>` set.
113	See :ref:`v4l2-mbus-format` on how to do this.
114    * - V4L2_SUBDEV_MBUS_CODE_CSC_HSV_ENC
115      - 0x00000004
116      - The driver allows the application to try to change the default HSV
117	encoding. The application can ask to configure the HSV encoding of the
118	subdevice when calling the :ref:`VIDIOC_SUBDEV_S_FMT <VIDIOC_SUBDEV_G_FMT>`
119	ioctl with :ref:`V4L2_MBUS_FRAMEFMT_SET_CSC <mbus-framefmt-set-csc>` set.
120	See :ref:`v4l2-mbus-format` on how to do this.
121    * - V4L2_SUBDEV_MBUS_CODE_CSC_QUANTIZATION
122      - 0x00000008
123      - The driver allows the application to try to change the default
124	quantization. The application can ask to configure the quantization of
125	the subdevice when calling the :ref:`VIDIOC_SUBDEV_S_FMT <VIDIOC_SUBDEV_G_FMT>`
126	ioctl with :ref:`V4L2_MBUS_FRAMEFMT_SET_CSC <mbus-framefmt-set-csc>` set.
127	See :ref:`v4l2-mbus-format` on how to do this.
128
129Return Value
130============
131
132On success 0 is returned, on error -1 and the ``errno`` variable is set
133appropriately. The generic error codes are described at the
134:ref:`Generic Error Codes <gen-errors>` chapter.
135
136EINVAL
137    The struct
138    :c:type:`v4l2_subdev_mbus_code_enum`
139    ``pad`` references a non-existing pad, or the ``index`` field is out
140    of bounds.
141