projects / linux-block.git / blame
| Commit | Line | Data |
|---|---|---|
| 74ba9207 | 1 | /* SPDX-License-Identifier: GPL-2.0-or-later */ |
| 1da177e4 | 2 | /* |
| 6bd4bcd3 | 3 | * hdlc.h -- General purpose ISDN HDLC decoder. |
| 1da177e4 LT |
4 | * |
| 5 | * Implementation of a HDLC decoder/encoder in software. | |
| 25985edc | 6 | * Necessary because some ISDN devices don't have HDLC |
| 6bd4bcd3 | 7 | * controllers. |
| 1da177e4 | 8 | * |
| 6bd4bcd3 | 9 | * Copyright (C) |
| c38fc3bc | 10 | * 2009 Karsten Keil <keil@b1-systems.de> |
| 6bd4bcd3 KK |
11 | * 2002 Wolfgang Mües <wolfgang@iksw-muees.de> |
| 12 | * 2001 Frode Isaksen <fisaksen@bewan.com> | |
| 13 | * 2001 Kai Germaschewski <kai.germaschewski@gmx.de> | |
| 1da177e4 LT |
14 | */ |
| 15 | ||
| 16 | #ifndef __ISDNHDLC_H__ | |
| 17 | #define __ISDNHDLC_H__ | |
| 18 | ||
| 19 | struct isdnhdlc_vars { | |
| 20 | int bit_shift; | |
| 21 | int hdlc_bits1; | |
| 22 | int data_bits; | |
| 6bd4bcd3 | 23 | int ffbit_shift; /* encoding only */ |
| 1da177e4 LT |
24 | int state; |
| 25 | int dstpos; | |
| 26 | ||
| 6bd4bcd3 | 27 | u16 crc; |
| 1da177e4 | 28 | |
| 6bd4bcd3 KK |
29 | u8 cbin; |
| 30 | u8 shift_reg; | |
| 31 | u8 ffvalue; | |
| 1da177e4 | 32 | |
| 6bd4bcd3 KK |
33 | /* set if transferring data */ |
| 34 | u32 data_received:1; | |
| 35 | /* set if D channel (send idle instead of flags) */ | |
| 36 | u32 dchannel:1; | |
| 37 | /* set if 56K adaptation */ | |
| 38 | u32 do_adapt56:1; | |
| 39 | /* set if in closing phase (need to send CRC + flag) */ | |
| 40 | u32 do_closing:1; | |
| c38fc3bc KK |
41 | /* set if data is bitreverse */ |
| 42 | u32 do_bitreverse:1; | |
| 1da177e4 LT |
43 | }; |
| 44 | ||
| c38fc3bc KK |
45 | /* Feature Flags */ |
| 46 | #define HDLC_56KBIT 0x01 | |
| 47 | #define HDLC_DCHANNEL 0x02 | |
| 48 | #define HDLC_BITREVERSE 0x04 | |
| 1da177e4 LT |
49 | |
| 50 | /* | |
| 51 | The return value from isdnhdlc_decode is | |
| 52 | the frame length, 0 if no complete frame was decoded, | |
| 53 | or a negative error number | |
| 54 | */ | |
| 55 | #define HDLC_FRAMING_ERROR 1 | |
| 56 | #define HDLC_CRC_ERROR 2 | |
| 57 | #define HDLC_LENGTH_ERROR 3 | |
| 58 | ||
| c38fc3bc | 59 | extern void isdnhdlc_rcv_init(struct isdnhdlc_vars *hdlc, u32 features); |
| 1da177e4 | 60 | |
| 6bd4bcd3 KK |
61 | extern int isdnhdlc_decode(struct isdnhdlc_vars *hdlc, const u8 *src, |
| 62 | int slen, int *count, u8 *dst, int dsize); | |
| 1da177e4 | 63 | |
| c38fc3bc | 64 | extern void isdnhdlc_out_init(struct isdnhdlc_vars *hdlc, u32 features); |
| 1da177e4 | 65 | |
| 6bd4bcd3 KK |
66 | extern int isdnhdlc_encode(struct isdnhdlc_vars *hdlc, const u8 *src, |
| 67 | u16 slen, int *count, u8 *dst, int dsize); | |
| 1da177e4 LT |
68 | |
| 69 | #endif /* __ISDNHDLC_H__ */ |