1 /* $OpenBSD: acpiutil.c,v 1.3 2006/12/19 23:01:47 deraadt Exp $ */
2 /*
3 * Copyright (c) 2005 Thorsten Lockert <tholo@sigmasoft.com>
4 *
5 * Permission to use, copy, modify, and distribute this software for any
6 * purpose with or without fee is hereby granted, provided that the above
7 * copyright notice and this permission notice appear in all copies.
8 *
9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16 */
17
18 #include <sys/types.h>
19 #include <sys/systm.h>
20 #include <sys/device.h>
21
22 #include <machine/bus.h>
23
24 #include <dev/acpi/acpireg.h>
25 #include <dev/acpi/acpivar.h>
26
27 u_int
28 acpi_checksum(const void *v, size_t len)
29 {
30 const u_char *p = v;
31 u_char s = 0;
32 int i;
33
34 for (i = 0; i < len; i++)
35 s += p[i];
36
37 if (s)
38 printf("acpi: bad checksum at %p\n", v);
39 return (s);
40 }