Annotation of sys/dev/onewire/onewire_bitbang.c, Revision 1.1
1.1 ! nbrk 1: /* $OpenBSD: onewire_bitbang.c,v 1.1 2006/03/04 16:27:03 grange Exp $ */
! 2:
! 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: */
! 18:
! 19: /*
! 20: * 1-Wire bus bit-banging routines.
! 21: */
! 22:
! 23: #include <sys/param.h>
! 24: #include <sys/systm.h>
! 25: #include <sys/device.h>
! 26:
! 27: #include <dev/onewire/onewirevar.h>
! 28:
! 29: int
! 30: onewire_bb_reset(const struct onewire_bbops *ops, void *arg)
! 31: {
! 32: int s, rv, i;
! 33:
! 34: s = splhigh();
! 35: ops->bb_tx(arg);
! 36: ops->bb_set(arg, 0);
! 37: DELAY(480);
! 38: ops->bb_set(arg, 1);
! 39: ops->bb_rx(arg);
! 40: DELAY(30);
! 41: for (i = 0; i < 6; i++) {
! 42: if ((rv = ops->bb_get(arg)) == 0)
! 43: break;
! 44: DELAY(20);
! 45: }
! 46: DELAY(450);
! 47: splx(s);
! 48:
! 49: return (rv);
! 50: }
! 51:
! 52: int
! 53: onewire_bb_bit(const struct onewire_bbops *ops, void *arg, int value)
! 54: {
! 55: int s, rv, i;
! 56:
! 57: s = splhigh();
! 58: ops->bb_tx(arg);
! 59: ops->bb_set(arg, 0);
! 60: DELAY(2);
! 61: if (value) {
! 62: ops->bb_set(arg, 1);
! 63: ops->bb_rx(arg);
! 64: for (i = 0; i < 15; i++) {
! 65: if ((rv = ops->bb_get(arg)) == 0)
! 66: break;
! 67: DELAY(2);
! 68: }
! 69: ops->bb_tx(arg);
! 70: }
! 71: DELAY(60);
! 72: ops->bb_set(arg, 1);
! 73: DELAY(5);
! 74: splx(s);
! 75:
! 76: return (rv);
! 77: }
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