1.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
2
3.. _VIDIOC_DV_TIMINGS_CAP:
4
5*********************************************************
6ioctl VIDIOC_DV_TIMINGS_CAP, VIDIOC_SUBDEV_DV_TIMINGS_CAP
7*********************************************************
8
9Name
10====
11
12VIDIOC_DV_TIMINGS_CAP - VIDIOC_SUBDEV_DV_TIMINGS_CAP - The capabilities of the Digital Video receiver/transmitter
13
14
15Synopsis
16========
17
18.. c:function:: int ioctl( int fd, VIDIOC_DV_TIMINGS_CAP, struct v4l2_dv_timings_cap *argp )
19    :name: VIDIOC_DV_TIMINGS_CAP
20
21.. c:function:: int ioctl( int fd, VIDIOC_SUBDEV_DV_TIMINGS_CAP, struct v4l2_dv_timings_cap *argp )
22    :name: VIDIOC_SUBDEV_DV_TIMINGS_CAP
23
24
25Arguments
26=========
27
28``fd``
29    File descriptor returned by :ref:`open() <func-open>`.
30
31``argp``
32    Pointer to struct :c:type:`v4l2_dv_timings_cap`.
33
34
35Description
36===========
37
38To query the capabilities of the DV receiver/transmitter applications
39initialize the ``pad`` field to 0, zero the reserved array of struct
40:c:type:`v4l2_dv_timings_cap` and call the
41``VIDIOC_DV_TIMINGS_CAP`` ioctl on a video node and the driver will fill
42in the structure.
43
44.. note::
45
46   Drivers may return different values after
47   switching the video input or output.
48
49When implemented by the driver DV capabilities of subdevices can be
50queried by calling the ``VIDIOC_SUBDEV_DV_TIMINGS_CAP`` ioctl directly
51on a subdevice node. The capabilities are specific to inputs (for DV
52receivers) or outputs (for DV transmitters), applications must specify
53the desired pad number in the struct
54:c:type:`v4l2_dv_timings_cap` ``pad`` field and
55zero the ``reserved`` array. Attempts to query capabilities on a pad
56that doesn't support them will return an ``EINVAL`` error code.
57
58
59.. tabularcolumns:: |p{1.2cm}|p{3.0cm}|p{13.3cm}|
60
61.. c:type:: v4l2_bt_timings_cap
62
63.. flat-table:: struct v4l2_bt_timings_cap
64    :header-rows:  0
65    :stub-columns: 0
66    :widths:       1 1 2
67
68    * - __u32
69      - ``min_width``
70      - Minimum width of the active video in pixels.
71    * - __u32
72      - ``max_width``
73      - Maximum width of the active video in pixels.
74    * - __u32
75      - ``min_height``
76      - Minimum height of the active video in lines.
77    * - __u32
78      - ``max_height``
79      - Maximum height of the active video in lines.
80    * - __u64
81      - ``min_pixelclock``
82      - Minimum pixelclock frequency in Hz.
83    * - __u64
84      - ``max_pixelclock``
85      - Maximum pixelclock frequency in Hz.
86    * - __u32
87      - ``standards``
88      - The video standard(s) supported by the hardware. See
89	:ref:`dv-bt-standards` for a list of standards.
90    * - __u32
91      - ``capabilities``
92      - Several flags giving more information about the capabilities. See
93	:ref:`dv-bt-cap-capabilities` for a description of the flags.
94    * - __u32
95      - ``reserved``\ [16]
96      - Reserved for future extensions.
97	Drivers must set the array to zero.
98
99
100
101.. tabularcolumns:: |p{1.0cm}|p{4.0cm}|p{3.5cm}|p{9.2cm}|
102
103.. c:type:: v4l2_dv_timings_cap
104
105.. flat-table:: struct v4l2_dv_timings_cap
106    :header-rows:  0
107    :stub-columns: 0
108    :widths:       1 1 2
109
110    * - __u32
111      - ``type``
112      - Type of DV timings as listed in :ref:`dv-timing-types`.
113    * - __u32
114      - ``pad``
115      - Pad number as reported by the media controller API. This field is
116	only used when operating on a subdevice node. When operating on a
117	video node applications must set this field to zero.
118    * - __u32
119      - ``reserved``\ [2]
120      - Reserved for future extensions.
121
122	Drivers and applications must set the array to zero.
123    * - union {
124      - (anonymous)
125    * - struct :c:type:`v4l2_bt_timings_cap`
126      - ``bt``
127      - BT.656/1120 timings capabilities of the hardware.
128    * - __u32
129      - ``raw_data``\ [32]
130    * - }
131      -
132
133.. tabularcolumns:: |p{7.0cm}|p{10.5cm}|
134
135.. _dv-bt-cap-capabilities:
136
137.. flat-table:: DV BT Timing capabilities
138    :header-rows:  0
139    :stub-columns: 0
140
141    * - Flag
142      - Description
143    * -
144      -
145    * - ``V4L2_DV_BT_CAP_INTERLACED``
146      - Interlaced formats are supported.
147    * - ``V4L2_DV_BT_CAP_PROGRESSIVE``
148      - Progressive formats are supported.
149    * - ``V4L2_DV_BT_CAP_REDUCED_BLANKING``
150      - CVT/GTF specific: the timings can make use of reduced blanking
151	(CVT) or the 'Secondary GTF' curve (GTF).
152    * - ``V4L2_DV_BT_CAP_CUSTOM``
153      - Can support non-standard timings, i.e. timings not belonging to
154	the standards set in the ``standards`` field.
155
156
157Return Value
158============
159
160On success 0 is returned, on error -1 and the ``errno`` variable is set
161appropriately. The generic error codes are described at the
162:ref:`Generic Error Codes <gen-errors>` chapter.
163