root/include/net/lapb.h

INCLUDED FROM

#ifndef _LAPB_H
#define _LAPB_H 
#include <linux/lapb.h>

#define LAPB_HEADER_LEN 20              /* LAPB over Ethernet + a bit more */

#define LAPB_ACK_PENDING_CONDITION      0x01
#define LAPB_REJECT_CONDITION           0x02
#define LAPB_PEER_RX_BUSY_CONDITION     0x04

/* Control field templates */
#define LAPB_I          0x00    /* Information frames */
#define LAPB_S          0x01    /* Supervisory frames */
#define LAPB_U          0x03    /* Unnumbered frames */

#define LAPB_RR         0x01    /* Receiver ready */
#define LAPB_RNR        0x05    /* Receiver not ready */
#define LAPB_REJ        0x09    /* Reject */

#define LAPB_SABM       0x2F    /* Set Asynchronous Balanced Mode */
#define LAPB_SABME      0x6F    /* Set Asynchronous Balanced Mode Extended */
#define LAPB_DISC       0x43    /* Disconnect */
#define LAPB_DM         0x0F    /* Disconnected mode */
#define LAPB_UA         0x63    /* Unnumbered acknowledge */
#define LAPB_FRMR       0x87    /* Frame reject */

#define LAPB_ILLEGAL    0x100   /* Impossible to be a real frame type */

#define LAPB_SPF        0x10    /* Poll/final bit for standard LAPB */
#define LAPB_EPF        0x01    /* Poll/final bit for extended LAPB */

#define LAPB_FRMR_W     0x01    /* Control field invalid        */
#define LAPB_FRMR_X     0x02    /* I field invalid              */
#define LAPB_FRMR_Y     0x04    /* I field too long             */
#define LAPB_FRMR_Z     0x08    /* Invalid N(R)                 */

#define LAPB_POLLOFF    0
#define LAPB_POLLON     1

/* LAPB C-bit */
#define LAPB_COMMAND    1
#define LAPB_RESPONSE   2

#define LAPB_ADDR_A     0x03
#define LAPB_ADDR_B     0x01
#define LAPB_ADDR_C     0x0F
#define LAPB_ADDR_D     0x07

/* Define Link State constants. */
enum {
        LAPB_STATE_0,   /* Disconnected State           */
        LAPB_STATE_1,   /* Awaiting Connection State    */
        LAPB_STATE_2,   /* Awaiting Disconnection State */
        LAPB_STATE_3,   /* Data Transfer State          */
        LAPB_STATE_4    /* Frame Reject State           */
};

#define LAPB_DEFAULT_MODE               (LAPB_STANDARD | LAPB_SLP | LAPB_DTE)
#define LAPB_DEFAULT_WINDOW             7               /* Window=7 */
#define LAPB_DEFAULT_T1                 (5 * HZ)        /* T1=5s    */
#define LAPB_DEFAULT_T2                 (1 * HZ)        /* T2=1s    */
#define LAPB_DEFAULT_N2                 20              /* N2=20    */

#define LAPB_SMODULUS   8
#define LAPB_EMODULUS   128

/*
 *      Information about the current frame.
 */
struct lapb_frame {
        unsigned short          type;           /* Parsed type          */
        unsigned short          nr, ns;         /* N(R), N(S)           */
        unsigned char           cr;             /* Command/Response     */
        unsigned char           pf;             /* Poll/Final           */
        unsigned char           control[2];     /* Original control data*/
};

/*
 *      The per LAPB connection control structure.
 */
struct lapb_cb {
        struct list_head        node;
        struct net_device       *dev;

        /* Link status fields */
        unsigned int            mode;
        unsigned char           state;
        unsigned short          vs, vr, va;
        unsigned char           condition;
        unsigned short          n2, n2count;
        unsigned short          t1, t2;
        struct timer_list       t1timer, t2timer;

        /* Internal control information */
        struct sk_buff_head     write_queue;
        struct sk_buff_head     ack_queue;
        unsigned char           window;
        const struct lapb_register_struct *callbacks;

        /* FRMR control information */
        struct lapb_frame       frmr_data;
        unsigned char           frmr_type;

        atomic_t                refcnt;
};

/* lapb_iface.c */
void lapb_connect_confirmation(struct lapb_cb *lapb, int);
void lapb_connect_indication(struct lapb_cb *lapb, int);
void lapb_disconnect_confirmation(struct lapb_cb *lapb, int);
void lapb_disconnect_indication(struct lapb_cb *lapb, int);
int lapb_data_indication(struct lapb_cb *lapb, struct sk_buff *);
int lapb_data_transmit(struct lapb_cb *lapb, struct sk_buff *);

/* lapb_in.c */
void lapb_data_input(struct lapb_cb *lapb, struct sk_buff *);

/* lapb_out.c */
void lapb_kick(struct lapb_cb *lapb);
void lapb_transmit_buffer(struct lapb_cb *lapb, struct sk_buff *, int);
void lapb_establish_data_link(struct lapb_cb *lapb);
void lapb_enquiry_response(struct lapb_cb *lapb);
void lapb_timeout_response(struct lapb_cb *lapb);
void lapb_check_iframes_acked(struct lapb_cb *lapb, unsigned short);
void lapb_check_need_response(struct lapb_cb *lapb, int, int);

/* lapb_subr.c */
void lapb_clear_queues(struct lapb_cb *lapb);
void lapb_frames_acked(struct lapb_cb *lapb, unsigned short);
void lapb_requeue_frames(struct lapb_cb *lapb);
int lapb_validate_nr(struct lapb_cb *lapb, unsigned short);
int lapb_decode(struct lapb_cb *lapb, struct sk_buff *, struct lapb_frame *);
void lapb_send_control(struct lapb_cb *lapb, int, int, int);
void lapb_transmit_frmr(struct lapb_cb *lapb);

/* lapb_timer.c */
void lapb_start_t1timer(struct lapb_cb *lapb);
void lapb_start_t2timer(struct lapb_cb *lapb);
void lapb_stop_t1timer(struct lapb_cb *lapb);
void lapb_stop_t2timer(struct lapb_cb *lapb);
int lapb_t1timer_running(struct lapb_cb *lapb);

/*
 * Debug levels.
 *      0 = Off
 *      1 = State Changes
 *      2 = Packets I/O and State Changes
 *      3 = Hex dumps, Packets I/O and State Changes.
 */
#define LAPB_DEBUG      0

#define lapb_dbg(level, fmt, ...)                       \
do {                                                    \
        if (level < LAPB_DEBUG)                         \
                pr_debug(fmt, ##__VA_ARGS__);           \
} while (0)

#endif