fa7f32422e
The uleds driver provides userspace LED devices. This tool is used to create one of these devices and monitor the changes in brighness for testing purposes. Signed-off-by: David Lechner <david@lechnology.com> Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
63 lines
1.3 KiB
C
63 lines
1.3 KiB
C
/*
|
|
* uledmon.c
|
|
*
|
|
* This program creates a new userspace LED class device and monitors it. A
|
|
* timestamp and brightness value is printed each time the brightness changes.
|
|
*
|
|
* Usage: uledmon <device-name>
|
|
*
|
|
* <device-name> is the name of the LED class device to be created. Pressing
|
|
* CTRL+C will exit.
|
|
*/
|
|
|
|
#include <fcntl.h>
|
|
#include <stdio.h>
|
|
#include <string.h>
|
|
#include <time.h>
|
|
#include <unistd.h>
|
|
|
|
#include <linux/uleds.h>
|
|
|
|
int main(int argc, char const *argv[])
|
|
{
|
|
struct uleds_user_dev uleds_dev;
|
|
int fd, ret;
|
|
int brightness;
|
|
struct timespec ts;
|
|
|
|
if (argc != 2) {
|
|
fprintf(stderr, "Requires <device-name> argument\n");
|
|
return 1;
|
|
}
|
|
|
|
strncpy(uleds_dev.name, argv[1], LED_MAX_NAME_SIZE);
|
|
uleds_dev.max_brightness = 100;
|
|
|
|
fd = open("/dev/uleds", O_RDWR);
|
|
if (fd == -1) {
|
|
perror("Failed to open /dev/uleds");
|
|
return 1;
|
|
}
|
|
|
|
ret = write(fd, &uleds_dev, sizeof(uleds_dev));
|
|
if (ret == -1) {
|
|
perror("Failed to write to /dev/uleds");
|
|
close(fd);
|
|
return 1;
|
|
}
|
|
|
|
while (1) {
|
|
ret = read(fd, &brightness, sizeof(brightness));
|
|
if (ret == -1) {
|
|
perror("Failed to read from /dev/uleds");
|
|
close(fd);
|
|
return 1;
|
|
}
|
|
clock_gettime(CLOCK_MONOTONIC, &ts);
|
|
printf("[%ld.%09ld] %u\n", ts.tv_sec, ts.tv_nsec, brightness);
|
|
}
|
|
|
|
close(fd);
|
|
|
|
return 0;
|
|
}
|