scull.h

适用于初学者的源码,简单的字符型设备的驱动源码,

#ifndef _SCULL_H_
#define _SCULL_H_

#include <linux/ioctl.h>

#ifndef SCULL_MAJOR
#define SCULL_MAJOR 0   
#endif

#ifndef SCULL_NR_DEVS
#define SCULL_NR_DEVS 3    
#endif

#ifndef SCULL_SIZE
#define SCULL_SIZE 4096
#endif

#ifdef __KERNEL__

typedef struct Scull_Dev {
   char *data;
   struct Scull_Dev *next;   
   unsigned long size;
   struct semaphore sem;    
} Scull_Dev;

#endif

/* 定义幻数 */
#define SCULL_IOC_MAGIC  'k'


/* 定义命令 */
#define SCULL_IOCPRINT   _IO(SCULL_IOC_MAGIC, 1)
#define SCULL_IOCGETDATA _IOR(SCULL_IOC_MAGIC, 2, int)
#define SCULL_IOCSETDATA _IOW(SCULL_IOC_MAGIC, 3, int)


#define SCULL_IOC_MAXNR 3

#endif /* _SCULL_H_ */