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1.. SPDX-License-Identifier: GPL-2.02 3.. _GPIOHANDLE_SET_CONFIG_IOCTL:4 5***************************6GPIOHANDLE_SET_CONFIG_IOCTL7***************************8 9.. warning::10 This ioctl is part of chardev_v1.rst and is obsoleted by11 gpio-v2-line-set-config-ioctl.rst.12 13Name14====15 16GPIOHANDLE_SET_CONFIG_IOCTL - Update the configuration of previously requested lines.17 18Synopsis19========20 21.. c:macro:: GPIOHANDLE_SET_CONFIG_IOCTL22 23``int ioctl(int handle_fd, GPIOHANDLE_SET_CONFIG_IOCTL, struct gpiohandle_config *config)``24 25Arguments26=========27 28``handle_fd``29 The file descriptor of the GPIO character device, as returned in the30 :c:type:`request.fd<gpiohandle_request>` by gpio-get-linehandle-ioctl.rst.31 32``config``33 The new :c:type:`configuration<gpiohandle_config>` to apply to the34 requested lines.35 36Description37===========38 39Update the configuration of previously requested lines, without releasing the40line or introducing potential glitches.41 42The configuration applies to all requested lines.43 44The same :ref:`gpio-get-linehandle-config-rules` and45:ref:`gpio-get-linehandle-config-support` that apply when requesting the46lines also apply when updating the line configuration, with the additional47restriction that a direction flag must be set. Requesting an invalid48configuration, including without a direction flag set, is an error49(**EINVAL**).50 51The motivating use case for this command is changing direction of52bi-directional lines between input and output, but it may be used more53generally to move lines seamlessly from one configuration state to another.54 55To only change the value of output lines, use56gpio-handle-set-line-values-ioctl.rst.57 58First added in 5.5.59 60Return Value61============62 63On success 0.64 65On error -1 and the ``errno`` variable is set appropriately.66Common error codes are described in error-codes.rst.67