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/*
* Driver for ST5481 USB ISDN modem
*
* Author Frode Isaksen
* Copyright 2001 by Frode Isaksen <fisaksen@bewan.com>
* 2001 by Kai Germaschewski <kai.germaschewski@gmx.de>
*
* This software may be used and distributed according to the terms
* of the GNU General Public License, incorporated herein by reference.
*
*/
#ifndef __ST5481_HDLC_H__
#define __ST5481_HDLC_H__
struct hdlc_vars {
int bit_shift;
int hdlc_bits1;
int data_bits;
int ffbit_shift; // encoding only
int state;
int dstpos;
int data_received:1; // set if transferring data
int dchannel:1; // set if D channel (send idle instead of flags)
int do_adapt56:1; // set if 56K adaptation
int do_closing:1; // set if in closing phase (need to send CRC + flag
unsigned short crc;
unsigned char cbin;
unsigned char shift_reg;
unsigned char ffvalue;
};
/*
The return value from hdlc_decode is
the frame length, 0 if no complete frame was decoded,
or a negative error number
*/
#define HDLC_FRAMING_ERROR 1
#define HDLC_CRC_ERROR 2
#define HDLC_LENGTH_ERROR 3
void
hdlc_rcv_init(struct hdlc_vars *hdlc, int do_adapt56);
int
hdlc_decode(struct hdlc_vars *hdlc, const unsigned char *src, int slen,int *count,
unsigned char *dst, int dsize);
void
hdlc_out_init(struct hdlc_vars *hdlc,int is_d_channel,int do_adapt56);
int
hdlc_encode(struct hdlc_vars *hdlc,const unsigned char *src,unsigned short slen,int *count,
unsigned char *dst,int dsize);
#endif
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