blob: 16dd50fc60ca7e33affbe6ae02bab21709c355cb [file] [log] [blame]
.. SPDX-License-Identifier: GPL-2.0
.. _GPIO_V2_LINE_SET_VALUES_IOCTL:
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GPIO_V2_LINE_SET_VALUES_IOCTL
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Name
====
GPIO_V2_LINE_SET_VALUES_IOCTL - Set the values of requested output lines.
Synopsis
========
.. c:macro:: GPIO_V2_LINE_SET_VALUES_IOCTL
``int ioctl(int req_fd, GPIO_V2_LINE_SET_VALUES_IOCTL, struct gpio_v2_line_values *values)``
Arguments
=========
``req_fd``
The file descriptor of the GPIO character device, as returned in the
:c:type:`request.fd<gpio_v2_line_request>` by gpio-v2-get-line-ioctl.rst.
``values``
The :c:type:`line_values<gpio_v2_line_values>` to set with the ``mask`` set
to indicate the subset of requested lines to set and ``bits`` set to
indicate the new value.
Description
===========
Set the values of requested output lines.
The values set are logical, indicating if the line is to be active or inactive.
The ``GPIO_V2_LINE_FLAG_ACTIVE_LOW`` flag controls the mapping between logical
values (active/inactive) and physical values (high/low).
If ``GPIO_V2_LINE_FLAG_ACTIVE_LOW`` is not set then active is high and inactive
is low. If ``GPIO_V2_LINE_FLAG_ACTIVE_LOW`` is set then active is low and
inactive is high.
Only the values of output lines may be set.
Attempting to set the value of an input line is an error (**EPERM**).
Return Value
============
On success 0.
On error -1 and the ``errno`` variable is set appropriately.
Common error codes are described in error-codes.rst.