Documentation/userspace-api/media/v4l/vidioc-g-std.rst
.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later .. c:namespace:: V4L
.. _VIDIOC_G_STD:
ioctl VIDIOC_G_STD, VIDIOC_S_STD, VIDIOC_SUBDEV_G_STD, VIDIOC_SUBDEV_S_STD
VIDIOC_G_STD - VIDIOC_S_STD - VIDIOC_SUBDEV_G_STD - VIDIOC_SUBDEV_S_STD - Query or select the video standard of the current input
.. c:macro:: VIDIOC_G_STD
int ioctl(int fd, VIDIOC_G_STD, v4l2_std_id *argp)
.. c:macro:: VIDIOC_S_STD
int ioctl(int fd, VIDIOC_S_STD, const v4l2_std_id *argp)
.. c:macro:: VIDIOC_SUBDEV_G_STD
int ioctl(int fd, VIDIOC_SUBDEV_G_STD, v4l2_std_id *argp)
.. c:macro:: VIDIOC_SUBDEV_S_STD
int ioctl(int fd, VIDIOC_SUBDEV_S_STD, const v4l2_std_id *argp)
fd
File descriptor returned by :c:func:open().
argp
Pointer to :c:type:v4l2_std_id.
To query and select the current video standard applications use the
:ref:VIDIOC_G_STD <VIDIOC_G_STD> and :ref:VIDIOC_S_STD <VIDIOC_G_STD> ioctls which take a pointer to a
:ref:v4l2_std_id <v4l2-std-id> type as argument. :ref:VIDIOC_G_STD <VIDIOC_G_STD>
can return a single flag or a set of flags as in struct
:c:type:v4l2_standard field id. The flags must be
unambiguous such that they appear in only one enumerated
struct :c:type:v4l2_standard structure.
:ref:VIDIOC_S_STD <VIDIOC_G_STD> accepts one or more flags, being a write-only ioctl it
does not return the actual new standard as :ref:VIDIOC_G_STD <VIDIOC_G_STD> does. When
no flags are given or the current input does not support the requested
standard the driver returns an EINVAL error code. When the standard set
is ambiguous drivers may return EINVAL or choose any of the requested
standards. If the current input or output does not support standard
video timings (e.g. if :ref:VIDIOC_ENUMINPUT
does not set the V4L2_IN_CAP_STD flag), then ENODATA error code is
returned.
Calling VIDIOC_SUBDEV_S_STD on a subdev device node that has been registered
in read-only mode is not allowed. An error is returned and the errno variable is
set to -EPERM.
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 :ref:VIDIOC_S_STD <VIDIOC_G_STD> parameter was unsuitable.
ENODATA Standard video timings are not supported for this input or output.
EPERM
VIDIOC_SUBDEV_S_STD has been called on a read-only subdevice.