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// SPDX-License-Identifier: GPL-2.0-or-later
// SPDX-FileCopyrightText: 2023 Kent Gibson <warthog618@gmail.com>
/*
* Example of a bi-directional line requested as input and then switched
* to output.
*/
#include <cstdlib>
#include <filesystem>
#include <gpiod.hpp>
#include <iostream>
namespace {
/* Example configuration - customize to suit your situation */
const ::std::filesystem::path chip_path("/dev/gpiochip0");
const ::gpiod::line::offset line_offset = 5;
} /* namespace */
int main()
{
/* request the line initially as an input */
auto request = ::gpiod::chip(chip_path)
.prepare_request()
.set_consumer("reconfigure-input-to-output")
.add_line_settings(
line_offset,
::gpiod::line_settings().set_direction(
::gpiod::line::direction::INPUT))
.do_request();
/* read the current line value */
::std::cout << line_offset << "="
<< (request.get_value(line_offset) ==
::gpiod::line::value::ACTIVE ?
"Active" :
"Inactive")
<< " (input)" << ::std::endl;
/* switch the line to an output and drive it low */
request.reconfigure_lines(::gpiod::line_config().add_line_settings(
line_offset,
::gpiod::line_settings()
.set_direction(::gpiod::line::direction::OUTPUT)
.set_output_value(::gpiod::line::value::INACTIVE)));
/* report the current driven value */
::std::cout << line_offset << "="
<< (request.get_value(line_offset) ==
::gpiod::line::value::ACTIVE ?
"Active" :
"Inactive")
<< " (output)" << ::std::endl;
return EXIT_SUCCESS;
}
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