/*
 * lcibuf.h -- definitions for the lci buffer driver and listen driver
 *             by Anthony Petillo 
 *             examples copied from Alessandro Rubini 
 *
 */

#ifndef _LCIBUF_H_
#define _LCIBUF_H_

#include <linux/ioctl.h> /* needed for the _IOW etc stuff used later */

/* version dependencies have been confined to a separate file */
#include "sysdep.h"
//#include <linux/exser.h>

/*
 * Macros to help debugging
 */

#undef PDEBUG             /* undef it, just in case */
#ifdef DDEBUG
# ifdef __KERNEL__
    /* This one if debugging is on, and kernel space */
#   define PDEBUG(fmt, args...) printk( KERN_DEBUG "lci: " fmt, ## args)
# else
    /* This one for user space */
#   define PDEBUG(fmt, args...) fprintf(stderr, fmt, ## args)
# endif
#else
# define PDEBUG(fmt, args...) /* not debugging: nothing */
#endif

#ifdef CONFIG_DEVFS_FS /* only if enabled, to avoid errors in 2.0 */
#include <linux/devfs_fs_kernel.h>
#else
  typedef void * devfs_handle_t;  /* avoid #ifdef inside the structure */
#endif

/*
 * This is somehow a hack: avoid ifdefs in the cleanup code by declaring
 * an empty procedure as a placeholder for devfs_unregister. This is
 * only done *unless* <linux/devfs_fs_kernel.h> was included, as that
 * header already implements placeholder for all the devfs functions
 */
/*............................................... degin-tag devfs-ifdef */
#ifndef DEVFS_FL_DEFAULT
extern inline void devfs_unregister(devfs_handle_t de) {}
#endif

extern devfs_handle_t lcibuf_devfs_dir;

typedef struct tag_lci_device {
  char * pbuf;			/* memory allocated for buffer - circular queue */
  char * pbuf_end;		/* end of buffer pointer */
  char * volatile head; 
  char * volatile tail;
  unsigned int size;		/* size of the buffer */
  struct semaphore sem;		/* mutual exclusion semaphore */
  volatile unsigned int usage_count; /* number open */
  volatile unsigned int rdwr_count; /* number open read/write */
  int	stop_buffering_in_direct;  /* if true, stop buffering input data in direct mode */ 
  struct wait_queue * in_queue;
  struct proc_dir_entry *ent;   // used with lwbuf proc entries, mainly to 
				// update the size of the buffer
  type_port port_type;
} type_lci_device;



/*
 * Split minors in two parts
 */
#define TYPE(dev)   (MINOR(dev) >> 4)  /* high nibble */
#define NUM(dev)    (MINOR(dev) & 0xf) /* low  nibble */

/*
 * The different configurable parameters
 */
extern int lcibuf_major;     /* main.c */

/*
 * Ioctl definitions
 */

/* Use 'k' as magic number */
#define LCIBUF_IOC_MAGIC      'k'
#define LCI_LISTEN_IOC_MAGIC  'j'

// lci buffer functions
#define LCIBUF_IOCRESET        _IO(LCIBUF_IOC_MAGIC,    0) 
#define LCIBUF_IOCSIZE         _IO(LCIBUF_IOC_MAGIC,    1)
#define LCIBUF_IOCBUFFERING    _IO(LCIBUF_IOC_MAGIC,    2)

// lci listen functions
#define LCI_LISTEN_IOCRESET    _IO(LCI_LISTEN_IOC_MAGIC, 0)

/*
 * S means "Set" through a ptr,
 * T means "Tell" directly with the argument value
 * G means "Get": reply by setting through a pointer
 * Q means "Query": response is on the return value
 * X means "eXchange": G and S atomically
 * H means "sHift": T and Q atomically
 */
//#define LCIBUF_IOCSQUANTUM _IOW(LCIBUF_IOC_MAGIC,  1, scull_quantum)
//#define LCIBUF_IOCSQSET    _IOW(LCIBUF_IOC_MAGIC,  2, scull_qset)
//#define LCIBUF_IOCTQUANTUM _IO(LCIBUF_IOC_MAGIC,   3)
//#define LCIBUF_IOCTQSET    _IO(LCIBUF_IOC_MAGIC,   4)
//#define LCIBUF_IOCGQUANTUM _IOR(LCIBUF_IOC_MAGIC,  5, scull_quantum)
//#define LCIBUF_IOCGQSET    _IOR(LCIBUF_IOC_MAGIC,  6, scull_qset)
//#define LCIBUF_IOCQQUANTUM _IO(LCIBUF_IOC_MAGIC,   7)
//#define LCIBUF_IOCQQSET    _IO(LCIBUF_IOC_MAGIC,   8)
//#define LCIBUF_IOCXQUANTUM _IOWR(LCIBUF_IOC_MAGIC, 9, scull_quantum)
//#define LCIBUF_IOCXQSET    _IOWR(LCIBUF_IOC_MAGIC,10, scull_qset)
//#define LCIBUF_IOCHQUANTUM _IO(LCIBUF_IOC_MAGIC,  11)
//#define LCIBUF_IOCHQSET    _IO(LCIBUF_IOC_MAGIC,  12)

/*
 * The other entities only have "Tell" and "Query", because they're
 * not printed in the book, and there's no need to have all six.
 * (The previous stuff was only there to show different ways to do it.
 */
#define LCIBUF_P_IOCTSIZE _IO(LCIBUF_IOC_MAGIC,   13)
#define LCIBUF_P_IOCQSIZE _IO(LCIBUF_IOC_MAGIC,   14)
/* ... more to come */
#define LCIBUF_IOCHARDRESET _IO(LCIBUF_IOC_MAGIC, 15) /* debugging tool */

#define LCIBUF_IOC_MAXNR 15

#define LCI_LISTEN_IOC_MAXNR 15

#endif /* _LCIBUF_H_ */