/*      $NetBSD: sir.h,v 1.8 2013/05/27 16:23:20 kiyohara Exp $ */

/*
* Copyright (c) 2001 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Lennart Augustsson ([email protected]) and Tommy Bohlin
* ([email protected]).
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
*    notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
*    notice, this list of conditions and the following disclaimer in the
*    documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/

/*
* Framing originally written by Tommy Bohlin.
*/

/* Protocol constants */
#define SIR_EXTRA_BOF            0xff
#define SIR_BOF                  0xc0
#define SIR_CE                   0x7d
#define SIR_EOF                  0xc1

#define SIR_ESC_BIT              0x20

enum framefsmstate {
       FSTATE_END_OF_FRAME,
       FSTATE_START_OF_FRAME,
       FSTATE_IN_DATA,
       FSTATE_IN_END
};

enum frameresult {
       FR_IDLE,
       FR_INPROGRESS,
       FR_FRAMEOK,
       FR_FRAMEBADFCS,
       FR_FRAMEMALFORMED,
       FR_BUFFEROVERRUN
};

struct framestate {
       u_int8_t *buffer;
       size_t buflen;
       size_t bufindex;

       enum framefsmstate fsmstate;
       u_int escaped;
       u_int state_index;
};

#define deframe_isclear(fs) ((fs)->fsmstate == FSTATE_END_OF_FRAME)

int irda_sir_frame(u_int8_t *, u_int, struct uio *, u_int);
void deframe_init(struct framestate *, u_int8_t *, size_t);
void deframe_clear(struct framestate *);
enum frameresult deframe_process(struct framestate *, u_int8_t const **,
                                size_t *);

/*
* CRC computation
*/
#define INITFCS 0xffff
#define GOODFCS 0xf0b8

extern const u_int16_t irda_fcstab[];

static __inline u_int16_t updateFCS(u_int16_t fcs, int c) {
       return (fcs >> 8) ^ irda_fcstab[(fcs^c) & 0xff];
}

u_int32_t crc_ccitt_16(u_int32_t, u_int8_t const*, size_t);