root/dev/onewire/onewire_subr.c

DEFINITIONS

1. onewire_crc
2. onewire_famname
3. onewire_matchbyfam

    1 /*      $OpenBSD: onewire_subr.c,v 1.2 2007/02/28 22:31:32 deraadt Exp $        */
    3 /*
    4  * Copyright (c) 2006 Alexander Yurchenko <grange@openbsd.org>
    5  *
    6  * Permission to use, copy, modify, and distribute this software for any
    7  * purpose with or without fee is hereby granted, provided that the above
    8  * copyright notice and this permission notice appear in all copies.
    9  *
   10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
   11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
   12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
   13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
   14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
   15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
   16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
   17  */
   19 /*
   20  * 1-Wire bus miscellaneous routines.
   21  */
   23 #include <sys/param.h>
   24 #include <sys/systm.h>
   25 #include <sys/device.h>
   27 #include <dev/onewire/onewiredevs.h>
   28 #include <dev/onewire/onewirereg.h>
   29 #include <dev/onewire/onewirevar.h>
   31 #ifdef ONEWIREVERBOSE
   32 #include <dev/onewire/onewiredevs_data.h>
   33 #endif
   35 static const u_int8_t crctable[] = {
   36         0x00, 0x5e, 0xbc, 0xe2, 0x61, 0x3f, 0xdd, 0x83,
   37         0xc2, 0x9c, 0x7e, 0x20, 0xa3, 0xfd, 0x1f, 0x41,
   38         0x9d, 0xc3, 0x21, 0x7f, 0xfc, 0xa2, 0x40, 0x1e,
   39         0x5f, 0x01, 0xe3, 0xbd, 0x3e, 0x60, 0x82, 0xdc,
   40         0x23, 0x7d, 0x9f, 0xc1, 0x42, 0x1c, 0xfe, 0xa0,
   41         0xe1, 0xbf, 0x5d, 0x03, 0x80, 0xde, 0x3c, 0x62,
   42         0xbe, 0xe0, 0x02, 0x5c, 0xdf, 0x81, 0x63, 0x3d,
   43         0x7c, 0x22, 0xc0, 0x9e, 0x1d, 0x43, 0xa1, 0xff,
   44         0x46, 0x18, 0xfa, 0xa4, 0x27, 0x79, 0x9b, 0xc5,
   45         0x84, 0xda, 0x38, 0x66, 0xe5, 0xbb, 0x59, 0x07,
   46         0xdb, 0x85, 0x67, 0x39, 0xba, 0xe4, 0x06, 0x58,
   47         0x19, 0x47, 0xa5, 0xfb, 0x78, 0x26, 0xc4, 0x9a,
   48         0x65, 0x3b, 0xd9, 0x87, 0x04, 0x5a, 0xb8, 0xe6,
   49         0xa7, 0xf9, 0x1b, 0x45, 0xc6, 0x98, 0x7a, 0x24,
   50         0xf8, 0xa6, 0x44, 0x1a, 0x99, 0xc7, 0x25, 0x7b,
   51         0x3a, 0x64, 0x86, 0xd8, 0x5b, 0x05, 0xe7, 0xb9,
   52         0x8c, 0xd2, 0x30, 0x6e, 0xed, 0xb3, 0x51, 0x0f,
   53         0x4e, 0x10, 0xf2, 0xac, 0x2f, 0x71, 0x93, 0xcd,
   54         0x11, 0x4f, 0xad, 0xf3, 0x70, 0x2e, 0xcc, 0x92,
   55         0xd3, 0x8d, 0x6f, 0x31, 0xb2, 0xec, 0x0e, 0x50,
   56         0xaf, 0xf1, 0x13, 0x4d, 0xce, 0x90, 0x72, 0x2c,
   57         0x6d, 0x33, 0xd1, 0x8f, 0x0c, 0x52, 0xb0, 0xee,
   58         0x32, 0x6c, 0x8e, 0xd0, 0x53, 0x0d, 0xef, 0xb1,
   59         0xf0, 0xae, 0x4c, 0x12, 0x91, 0xcf, 0x2d, 0x73,
   60         0xca, 0x94, 0x76, 0x28, 0xab, 0xf5, 0x17, 0x49,
   61         0x08, 0x56, 0xb4, 0xea, 0x69, 0x37, 0xd5, 0x8b,
   62         0x57, 0x09, 0xeb, 0xb5, 0x36, 0x68, 0x8a, 0xd4,
   63         0x95, 0xcb, 0x29, 0x77, 0xf4, 0xaa, 0x48, 0x16,
   64         0xe9, 0xb7, 0x55, 0x0b, 0x88, 0xd6, 0x34, 0x6a,
   65         0x2b, 0x75, 0x97, 0xc9, 0x4a, 0x14, 0xf6, 0xa8,
   66         0x74, 0x2a, 0xc8, 0x96, 0x15, 0x4b, 0xa9, 0xf7,
   67         0xb6, 0xe8, 0x0a, 0x54, 0xd7, 0x89, 0x6b, 0x35
   68 };
   70 int
onewire_crc(const void *buf, int len)
   72 {
   73         const u_int8_t *p = buf;
u_int8_t crc = 0;
   76         while (len--)
crc = crctable[crc ^ *p++];
   79         return (crc);
   80 }
   82 const char *
onewire_famname(int type)
   84 {
   85 #ifdef ONEWIREVERBOSE
   86         const struct onewire_family *of;
   88         for (of = onewire_famtab; of->of_name != NULL; of++)
   89                 if (of->of_type == type)
   90                         return (of->of_name);
   91 #endif
   93         return (NULL);
   94 }
   96 int
onewire_matchbyfam(struct onewire_attach_args *oa,
   98     const struct onewire_matchfam *fams, int nent)
   99 {
  100         const struct onewire_matchfam *om;
  101         int i;
  103         for (i = 0, om = fams; i < nent; i++, om++)
  104                 if (ONEWIRE_ROM_FAMILY_TYPE(oa->oa_rom) == om->om_type)
  105                         return (1);
  107         return (0);
  108 }