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-rw-r--r--drivers/isdn/hisax/isdnhdlc.h72
1 files changed, 72 insertions, 0 deletions
diff --git a/drivers/isdn/hisax/isdnhdlc.h b/drivers/isdn/hisax/isdnhdlc.h
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+++ b/drivers/isdn/hisax/isdnhdlc.h
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+/*
+ * isdnhdlc.h -- General purpose ISDN HDLC decoder.
+ *
+ * Implementation of a HDLC decoder/encoder in software.
+ * Neccessary because some ISDN devices don't have HDLC
+ * controllers. Also included: a bit reversal table.
+ *
+ *Copyright (C) 2002 Wolfgang Mües <wolfgang@iksw-muees.de>
+ * 2001 Frode Isaksen <fisaksen@bewan.com>
+ * 2001 Kai Germaschewski <kai.germaschewski@gmx.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#ifndef __ISDNHDLC_H__
+#define __ISDNHDLC_H__
+
+struct isdnhdlc_vars {
+ int bit_shift;
+ int hdlc_bits1;
+ int data_bits;
+ int ffbit_shift; // encoding only
+ int state;
+ int dstpos;
+
+ unsigned short crc;
+
+ unsigned char cbin;
+ unsigned char shift_reg;
+ unsigned char ffvalue;
+
+ 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
+};
+
+
+/*
+ The return value from isdnhdlc_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
+
+extern const unsigned char isdnhdlc_bit_rev_tab[256];
+
+extern void isdnhdlc_rcv_init (struct isdnhdlc_vars *hdlc, int do_adapt56);
+
+extern int isdnhdlc_decode (struct isdnhdlc_vars *hdlc, const unsigned char *src, int slen,int *count,
+ unsigned char *dst, int dsize);
+
+extern void isdnhdlc_out_init (struct isdnhdlc_vars *hdlc,int is_d_channel,int do_adapt56);
+
+extern int isdnhdlc_encode (struct isdnhdlc_vars *hdlc,const unsigned char *src,unsigned short slen,int *count,
+ unsigned char *dst,int dsize);
+
+#endif /* __ISDNHDLC_H__ */