1 /* $NetBSD: sir.h,v 1.8 2013/05/27 16:23:20 kiyohara Exp $ */
2
3 /*
4 * Copyright (c) 2001 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Lennart Augustsson (lennart@augustsson.net) and Tommy Bohlin
9 * (tommy@gatespace.com).
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
22 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
24 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30 * POSSIBILITY OF SUCH DAMAGE.
31 */
32
33 /*
34 * Framing originally written by Tommy Bohlin.
35 */
36
37 /* Protocol constants */
38 #define SIR_EXTRA_BOF 0xff
39 #define SIR_BOF 0xc0
40 #define SIR_CE 0x7d
41 #define SIR_EOF 0xc1
42
43 #define SIR_ESC_BIT 0x20
44
45 enum framefsmstate {
46 FSTATE_END_OF_FRAME,
47 FSTATE_START_OF_FRAME,
48 FSTATE_IN_DATA,
49 FSTATE_IN_END
50 };
51
52 enum frameresult {
53 FR_IDLE,
54 FR_INPROGRESS,
55 FR_FRAMEOK,
56 FR_FRAMEBADFCS,
57 FR_FRAMEMALFORMED,
58 FR_BUFFEROVERRUN
59 };
60
61 struct framestate {
62 u_int8_t *buffer;
63 size_t buflen;
64 size_t bufindex;
65
66 enum framefsmstate fsmstate;
67 u_int escaped;
68 u_int state_index;
69 };
70
71 #define deframe_isclear(fs) ((fs)->fsmstate == FSTATE_END_OF_FRAME)
72
73 int irda_sir_frame(u_int8_t *, u_int, struct uio *, u_int);
74 void deframe_init(struct framestate *, u_int8_t *, size_t);
75 void deframe_clear(struct framestate *);
76 enum frameresult deframe_process(struct framestate *, u_int8_t const **,
77 size_t *);
78
79 /*
80 * CRC computation
81 */
82 #define INITFCS 0xffff
83 #define GOODFCS 0xf0b8
84
85 extern const u_int16_t irda_fcstab[];
86
updateFCS(u_int16_t fcs,int c)87 static __inline u_int16_t updateFCS(u_int16_t fcs, int c) {
88 return (fcs >> 8) ^ irda_fcstab[(fcs^c) & 0xff];
89 }
90
91 u_int32_t crc_ccitt_16(u_int32_t, u_int8_t const*, size_t);
92