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/* SPDX-License-Identifier: 0BSD */
/* SPDX-FileCopyrightText: 2023-2025 Uwe Kleine-König <u.kleine-koenig@baylibre.com> */
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <pwm.h>
int main(int argc, char *const argv[])
{
struct pwm_chip *chip;
struct pwm *pwm;
struct pwm_waveform wf = {
.period_length_ns = 50000,
.duty_length_ns = 0,
.duty_offset_ns = 0,
};
int ret;
int opt;
long long step = 1;
unsigned int chipno = 0;
unsigned int pwmno = 0;
while ((opt = getopt(argc, argv, "c:p:P:S:")) != -1) {
switch (opt) {
case 'c':
chipno = atoi(optarg);
break;
case 'p':
pwmno = atoi(optarg);
break;
case 'P':
wf.period_length_ns = atoll(optarg);
break;
case 'S':
step = atoll(optarg);
if (!step) {
errno = EINVAL;
perror("Invalid step value");
return EXIT_FAILURE;
}
break;
default:
return EXIT_FAILURE;
}
}
chip = pwm_chip_open_by_number(chipno);
if (!chip) {
perror("Failed to open pwmchip0");
return EXIT_FAILURE;
}
pwm = pwm_chip_get_pwm(chip, pwmno);
if (!pwm) {
perror("Failed to get pwm0");
return EXIT_FAILURE;
}
for (wf.duty_length_ns = (step > 0 ? 0 : wf.period_length_ns); wf.duty_length_ns <= wf.period_length_ns; wf.duty_length_ns += step) {
ret = pwm_set_waveform(pwm, &wf);
if (ret < 0) {
perror("Failed to configure PWM");
return EXIT_FAILURE;
}
}
pwm_chip_close(chip);
return EXIT_SUCCESS;
}
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