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// SPDX-License-Identifier: GPL-2.0-or-later
/*
* GPIO character device helper for reading chip information.
*
* Copyright (C) 2021 Bartosz Golaszewski <brgl@bgdev.pl>
*/
#include <fcntl.h>
#include <linux/gpio.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/ioctl.h>
#include <sys/types.h>
static void print_usage(void)
{
printf("usage:\n");
printf(" gpio-chip-info <chip path> [name|label|num-lines]\n");
}
int main(int argc, char **argv)
{
struct gpiochip_info info;
int fd, ret;
if (argc != 3) {
print_usage();
return EXIT_FAILURE;
}
fd = open(argv[1], O_RDWR);
if (fd < 0) {
perror("unable to open the GPIO chip");
return EXIT_FAILURE;
}
memset(&info, 0, sizeof(info));
ret = ioctl(fd, GPIO_GET_CHIPINFO_IOCTL, &info);
if (ret) {
perror("chip info ioctl failed");
return EXIT_FAILURE;
}
if (strcmp(argv[2], "name") == 0) {
printf("%s\n", info.name);
} else if (strcmp(argv[2], "label") == 0) {
printf("%s\n", info.label);
} else if (strcmp(argv[2], "num-lines") == 0) {
printf("%u\n", info.lines);
} else {
fprintf(stderr, "unknown command: %s\n", argv[2]);
return EXIT_FAILURE;
}
return EXIT_SUCCESS;
}
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