Listing 1. barcode.h

/* barcode.h */

#define COM_BASE      0x3f8    /* COM1 aka ttys0 */
/* #define COM_BASE   0x2f8       COM2 aka ttys1 */


#define BARCODE_MAJOR       42


#define DEBUG

#ifdef DEBUG
#define MSG(string, args...) if (barcode_debug)\
    printk(KERN_DEBUG "barcode: " string, ##args)
#else
#define MSG(string, args...)
#endif