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Diffstat (limited to '')
| -rw-r--r-- | Documentation/userspace-api/media/v4l/vidioc-subdev-g-fmt.rst (renamed from Documentation/media/uapi/v4l/vidioc-subdev-g-fmt.rst) | 38 |
1 files changed, 18 insertions, 20 deletions
diff --git a/Documentation/media/uapi/v4l/vidioc-subdev-g-fmt.rst b/Documentation/userspace-api/media/v4l/vidioc-subdev-g-fmt.rst index 472577bd1745..7acdbb939d89 100644 --- a/Documentation/media/uapi/v4l/vidioc-subdev-g-fmt.rst +++ b/Documentation/userspace-api/media/v4l/vidioc-subdev-g-fmt.rst @@ -1,11 +1,5 @@ -.. Permission is granted to copy, distribute and/or modify this -.. document under the terms of the GNU Free Documentation License, -.. Version 1.1 or any later version published by the Free Software -.. Foundation, with no Invariant Sections, no Front-Cover Texts -.. and no Back-Cover Texts. A copy of the license is included at -.. Documentation/media/uapi/fdl-appendix.rst. -.. -.. TODO: replace it to GFDL-1.1-or-later WITH no-invariant-sections +.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later +.. c:namespace:: V4L .. _VIDIOC_SUBDEV_G_FMT: @@ -18,27 +12,26 @@ Name VIDIOC_SUBDEV_G_FMT - VIDIOC_SUBDEV_S_FMT - Get or set the data format on a subdev pad - Synopsis ======== -.. c:function:: int ioctl( int fd, VIDIOC_SUBDEV_G_FMT, struct v4l2_subdev_format *argp ) - :name: VIDIOC_SUBDEV_G_FMT +.. c:macro:: VIDIOC_SUBDEV_G_FMT + +``int ioctl(int fd, VIDIOC_SUBDEV_G_FMT, struct v4l2_subdev_format *argp)`` -.. c:function:: int ioctl( int fd, VIDIOC_SUBDEV_S_FMT, struct v4l2_subdev_format *argp ) - :name: VIDIOC_SUBDEV_S_FMT +.. c:macro:: VIDIOC_SUBDEV_S_FMT +``int ioctl(int fd, VIDIOC_SUBDEV_S_FMT, struct v4l2_subdev_format *argp)`` Arguments ========= ``fd`` - File descriptor returned by :ref:`open() <func-open>`. + File descriptor returned by :c:func:`open()`. ``argp`` Pointer to struct :c:type:`v4l2_subdev_format`. - Description =========== @@ -78,13 +71,17 @@ current links configuration or sub-device controls value. For instance, a low-pass noise filter might crop pixels at the frame boundaries, modifying its output frame size. +If the subdev device node has been registered in read-only mode, calls to +``VIDIOC_SUBDEV_S_FMT`` are only valid if the ``which`` field is set to +``V4L2_SUBDEV_FORMAT_TRY``, otherwise an error is returned and the errno +variable is set to ``-EPERM``. + Drivers must not return an error solely because the requested format doesn't match the device capabilities. They must instead modify the format to match what the hardware can provide. The modified format should be as close as possible to the original request. - -.. tabularcolumns:: |p{4.4cm}|p{4.4cm}|p{8.7cm}| +.. tabularcolumns:: |p{4.4cm}|p{4.4cm}|p{8.5cm}| .. c:type:: v4l2_subdev_format @@ -110,8 +107,7 @@ should be as close as possible to the original request. the array to zero. - -.. tabularcolumns:: |p{6.6cm}|p{2.2cm}|p{8.7cm}| +.. tabularcolumns:: |p{6.6cm}|p{2.2cm}|p{8.5cm}| .. _v4l2-subdev-format-whence: @@ -127,7 +123,6 @@ should be as close as possible to the original request. - 1 - Active formats, applied to the hardware. - Return Value ============ @@ -146,6 +141,9 @@ EINVAL ``pad`` references a non-existing pad, or the ``which`` field references a non-existing format. +EPERM + The ``VIDIOC_SUBDEV_S_FMT`` ioctl has been called on a read-only subdevice + and the ``which`` field is set to ``V4L2_SUBDEV_FORMAT_ACTIVE``. ============ |