aboutsummaryrefslogtreecommitdiffstats
path: root/Documentation/userspace-api/media/v4l/vidioc-subdev-enum-mbus-code.rst
blob: 3b6a8044c3917b9cef74695aae85beefe8d26b3e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later

.. _VIDIOC_SUBDEV_ENUM_MBUS_CODE:

**********************************
ioctl VIDIOC_SUBDEV_ENUM_MBUS_CODE
**********************************

Name
====

VIDIOC_SUBDEV_ENUM_MBUS_CODE - Enumerate media bus formats


Synopsis
========

.. c:function:: int ioctl( int fd, VIDIOC_SUBDEV_ENUM_MBUS_CODE, struct v4l2_subdev_mbus_code_enum * argp )
    :name: VIDIOC_SUBDEV_ENUM_MBUS_CODE


Arguments
=========

``fd``
    File descriptor returned by :ref:`open() <func-open>`.

``argp``
    Pointer to struct :c:type:`v4l2_subdev_mbus_code_enum`.


Description
===========

To enumerate media bus formats available at a given sub-device pad
applications initialize the ``pad``, ``which`` and ``index`` fields of
struct
:c:type:`v4l2_subdev_mbus_code_enum` and
call the :ref:`VIDIOC_SUBDEV_ENUM_MBUS_CODE` ioctl with a pointer to this
structure. Drivers fill the rest of the structure or return an ``EINVAL``
error code if either the ``pad`` or ``index`` are invalid. All media bus
formats are enumerable by beginning at index zero and incrementing by
one until ``EINVAL`` is returned.

Available media bus formats may depend on the current 'try' formats at
other pads of the sub-device, as well as on the current active links.
See :ref:`VIDIOC_SUBDEV_G_FMT` for more
information about the try formats.


.. c:type:: v4l2_subdev_mbus_code_enum

.. tabularcolumns:: |p{4.4cm}|p{4.4cm}|p{8.7cm}|

.. flat-table:: struct v4l2_subdev_mbus_code_enum
    :header-rows:  0
    :stub-columns: 0
    :widths:       1 1 2

    * - __u32
      - ``pad``
      - Pad number as reported by the media controller API.
    * - __u32
      - ``index``
      - Number of the format in the enumeration, set by the application.
    * - __u32
      - ``code``
      - The media bus format code, as defined in
	:ref:`v4l2-mbus-format`.
    * - __u32
      - ``which``
      - Media bus format codes to be enumerated, from enum
	:ref:`v4l2_subdev_format_whence <v4l2-subdev-format-whence>`.
    * - __u32
      - ``flags``
      - See :ref:`v4l2-subdev-mbus-code-flags`
    * - __u32
      - ``reserved``\ [7]
      - Reserved for future extensions. Applications and drivers must set
	the array to zero.



.. tabularcolumns:: |p{4.4cm}|p{4.4cm}|p{7.7cm}|

.. _v4l2-subdev-mbus-code-flags:

.. flat-table:: Subdev Media Bus Code Enumerate Flags
    :header-rows:  0
    :stub-columns: 0
    :widths:       1 1 2

    * - V4L2_SUBDEV_MBUS_CODE_CSC_COLORSPACE
      - 0x00000001
      - The driver allows the application to try to change the default colorspace
	encoding. The application can ask to configure the colorspace of the
	subdevice when calling the :ref:`VIDIOC_SUBDEV_S_FMT <VIDIOC_SUBDEV_G_FMT>`
	ioctl with :ref:`V4L2_MBUS_FRAMEFMT_SET_CSC <mbus-framefmt-set-csc>` set.
	See :ref:`v4l2-mbus-format` on how to do this.
    * - V4L2_SUBDEV_MBUS_CODE_CSC_XFER_FUNC
      - 0x00000002
      - The driver allows the application to try to change the default transform function.
	The application can ask to configure the transform function of
	the subdevice when calling the :ref:`VIDIOC_SUBDEV_S_FMT <VIDIOC_SUBDEV_G_FMT>`
	ioctl with :ref:`V4L2_MBUS_FRAMEFMT_SET_CSC <mbus-framefmt-set-csc>` set.
	See :ref:`v4l2-mbus-format` on how to do this.
    * - V4L2_SUBDEV_MBUS_CODE_CSC_YCBCR_ENC
      - 0x00000004
      - The driver allows the application to try to change the default Y'CbCr
	encoding. The application can ask to configure the Y'CbCr encoding of the
	subdevice when calling the :ref:`VIDIOC_SUBDEV_S_FMT <VIDIOC_SUBDEV_G_FMT>`
	ioctl with :ref:`V4L2_MBUS_FRAMEFMT_SET_CSC <mbus-framefmt-set-csc>` set.
	See :ref:`v4l2-mbus-format` on how to do this.
    * - V4L2_SUBDEV_MBUS_CODE_CSC_HSV_ENC
      - 0x00000004
      - The driver allows the application to try to change the default HSV
	encoding. The application can ask to configure the HSV encoding of the
	subdevice when calling the :ref:`VIDIOC_SUBDEV_S_FMT <VIDIOC_SUBDEV_G_FMT>`
	ioctl with :ref:`V4L2_MBUS_FRAMEFMT_SET_CSC <mbus-framefmt-set-csc>` set.
	See :ref:`v4l2-mbus-format` on how to do this.
    * - V4L2_SUBDEV_MBUS_CODE_CSC_QUANTIZATION
      - 0x00000008
      - The driver allows the application to try to change the default
	quantization. The application can ask to configure the quantization of
	the subdevice when calling the :ref:`VIDIOC_SUBDEV_S_FMT <VIDIOC_SUBDEV_G_FMT>`
	ioctl with :ref:`V4L2_MBUS_FRAMEFMT_SET_CSC <mbus-framefmt-set-csc>` set.
	See :ref:`v4l2-mbus-format` on how to do this.

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_subdev_mbus_code_enum`
    ``pad`` references a non-existing pad, or the ``index`` field is out
    of bounds.