#define LCD_IOC_MAGIC   'k'
#define LCD_MAJOR       42

// general constants
#define DEG     0xDF    /* degree symbol */

// ioctl constants
#define LCD_Line	_IO(LCD_IOC_MAGIC,1)
#define LCD_Clear	_IO(LCD_IOC_MAGIC,2)
#define LCD_String	_IO(LCD_IOC_MAGIC,3)
#define LCD_Button	_IO(LCD_IOC_MAGIC,4)

struct lcd_display {
	char str[20];
	int button;
};