Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  1) // SPDX-License-Identifier: GPL-2.0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  3)  * uledmon.c
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  4)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  5)  * This program creates a new userspace LED class device and monitors it. A
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  6)  * timestamp and brightness value is printed each time the brightness changes.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  7)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  8)  * Usage: uledmon <device-name>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  9)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10)  * <device-name> is the name of the LED class device to be created. Pressing
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11)  * CTRL+C will exit.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) #include <fcntl.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) #include <stdio.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) #include <string.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) #include <time.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) #include <unistd.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) #include <linux/uleds.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) int main(int argc, char const *argv[])
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) 	struct uleds_user_dev uleds_dev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) 	int fd, ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) 	int brightness;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) 	struct timespec ts;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) 	if (argc != 2) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) 		fprintf(stderr, "Requires <device-name> argument\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) 		return 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) 	strncpy(uleds_dev.name, argv[1], LED_MAX_NAME_SIZE);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) 	uleds_dev.max_brightness = 100;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) 	fd = open("/dev/uleds", O_RDWR);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) 	if (fd == -1) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) 		perror("Failed to open /dev/uleds");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) 		return 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) 	ret = write(fd, &uleds_dev, sizeof(uleds_dev));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) 	if (ret == -1) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) 		perror("Failed to write to /dev/uleds");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) 		close(fd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) 		return 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) 	while (1) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) 		ret = read(fd, &brightness, sizeof(brightness));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) 		if (ret == -1) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) 			perror("Failed to read from /dev/uleds");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) 			close(fd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) 			return 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) 		clock_gettime(CLOCK_MONOTONIC, &ts);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) 		printf("[%ld.%09ld] %u\n", ts.tv_sec, ts.tv_nsec, brightness);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) 	close(fd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) }