Documentation/userspace-api/gpio/gpio-handle-set-config-ioctl.rst
.. SPDX-License-Identifier: GPL-2.0
.. _GPIOHANDLE_SET_CONFIG_IOCTL:
GPIOHANDLE_SET_CONFIG_IOCTL
.. warning:: This ioctl is part of chardev_v1.rst and is obsoleted by gpio-v2-line-set-config-ioctl.rst.
GPIOHANDLE_SET_CONFIG_IOCTL - Update the configuration of previously requested lines.
.. c:macro:: GPIOHANDLE_SET_CONFIG_IOCTL
int ioctl(int handle_fd, GPIOHANDLE_SET_CONFIG_IOCTL, struct gpiohandle_config *config)
handle_fd
The file descriptor of the GPIO character device, as returned in the
:c:type:request.fd<gpiohandle_request> by gpio-get-linehandle-ioctl.rst.
config
The new :c:type:configuration<gpiohandle_config> to apply to the
requested lines.
Update the configuration of previously requested lines, without releasing the line or introducing potential glitches.
The configuration applies to all requested lines.
The same :ref:gpio-get-linehandle-config-rules and
:ref:gpio-get-linehandle-config-support that apply when requesting the
lines also apply when updating the line configuration, with the additional
restriction that a direction flag must be set. Requesting an invalid
configuration, including without a direction flag set, is an error
(EINVAL).
The motivating use case for this command is changing direction of bi-directional lines between input and output, but it may be used more generally to move lines seamlessly from one configuration state to another.
To only change the value of output lines, use gpio-handle-set-line-values-ioctl.rst.
First added in 5.5.
On success 0.
On error -1 and the errno variable is set appropriately.
Common error codes are described in error-codes.rst.