diff --git a/10_chardev/include/ioctl.h b/10_chardev/include/ioctl.h
new file mode 100644
index 0000000..e0e11ad
--- /dev/null
+++ b/10_chardev/include/ioctl.h
@@ -0,0 +1,13 @@
+#ifndef PCI_IOCTL_H
+#define PCI_IOCTL_H
+#include <linux/ioctl.h>
+
+#define GREEN_LEN_ON _IO('q', 1)
+#define GREEN_LEN_OFF _IO('q', 2)
+
+#define RED_LEN_ON _IO('q', 3)
+#define RED_LEN_OFF _IO('q', 4)
+
+#define DEVICE_NAME "/dev/led"
+
+#endif // MY_IOCTL_H
diff --git a/10_chardev/user/Makefile b/10_chardev/user/Makefile
new file mode 100644
index 0000000..1698b75
--- /dev/null
+++ b/10_chardev/user/Makefile
@@ -0,0 +1,10 @@
+all: led_ioctl
+
+led_ioctl: led_ioctl.c
+	g++ -o $@ $< -L.-std=c++11
+
+clean:
+	@rm -vf led_ioctl
+
+clear: clean
+	@rm -vf led_ioctl
diff --git a/10_chardev/user/led_ioctl.c b/10_chardev/user/led_ioctl.c
new file mode 100644
index 0000000..d5505eb
--- /dev/null
+++ b/10_chardev/user/led_ioctl.c
@@ -0,0 +1,100 @@
+#include <stdio.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <string.h>
+#include <errno.h>
+#include <sys/ioctl.h>
+#include <iostream>
+#include <unistd.h>
+#include <stdlib.h>
+#include "../include/ioctl.h"
+
+using namespace std;
+
+int main(int argc, char *argv[])
+{
+	int fd, i, ret;
+    char buf[4096*16];
+	fd = 0;
+
+	fprintf(stderr, "%s:%d: Usage: %s cmd\n", __FILE__, __LINE__, *argv);
+	fprintf(stderr, "1 cmd: gree len switch on\n");
+	fprintf(stderr, "2 cmd: gree len switch off\n");
+	fprintf(stderr, "3 cmd: red len switch on\n");
+	fprintf(stderr, "4 cmd: red len switch off\n");
+
+	bool green_on_cmd = false;
+	bool red_on_cmd = false;
+	std::string file_name = DEVICE_NAME;
+
+    if(argc >= 2)
+    {
+		int argument = atoi(argv[1]);
+		switch(argument)
+		{
+			case 1:
+			{
+				green_on_cmd = true;
+				break;
+			}
+			case 2:
+			{
+				green_on_cmd = false;
+				break;
+			}
+			case 3:
+			{
+				red_on_cmd = true;
+				break;
+			}
+			case 4:
+			{
+				red_on_cmd = false;
+				break;
+			}
+		}
+	}
+
+
+	fd = open(file_name.c_str(), O_RDWR);
+    if (fd == -1) {
+		fprintf(stderr, "%s:%d: Can't open %s\n", __FILE__, __LINE__, file_name.c_str());
+		return 1;
+    }
+
+	if(green_on_cmd )
+    {
+		if (ioctl(fd, GREEN_LEN_ON) == -1)
+		{
+			perror("query_apps ioctl");
+		}
+    }
+	else
+	{
+		if (ioctl(fd, GREEN_LEN_OFF) == -1)
+		{
+			perror("query_apps ioctl");
+		}
+	}
+
+	if(red_on_cmd )
+	{
+		if (ioctl(fd, RED_LEN_ON) == -1)
+		{
+			perror("query_apps ioctl");
+		}
+	}
+	else
+	{
+		if (ioctl(fd, RED_LEN_OFF) == -1)
+		{
+			perror("query_apps ioctl");
+		}
+	}
+
+    close(fd);
+
+    return 0;
+}