1/*-
2 * Copyright (c) 2004 Poul-Henning Kamp
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer
10 *    in this position and unchanged.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 *
26 */
27
28#include <sys/cdefs.h>
29__FBSDID("$FreeBSD$");
30
31#include <sys/param.h>
32#include <sys/systm.h>
33#include <sys/conf.h>
34#include <sys/uio.h>
35#include <sys/kernel.h>
36#include <sys/malloc.h>
37#include <sys/module.h>
38#include <sys/watchdog.h>
39#include <sys/bus.h>
40#include <machine/bus.h>
41
42static struct cdev *wd_dev;
43static volatile u_int wd_last_u;
44
45static int
46kern_do_pat(u_int utim)
47{
48	int error;
49
50	if ((utim & WD_LASTVAL) != 0 && (utim & WD_INTERVAL) > 0)
51		return (EINVAL);
52
53	if ((utim & WD_LASTVAL) != 0) {
54		MPASS((wd_last_u & ~WD_INTERVAL) == 0);
55		utim &= ~WD_LASTVAL;
56		utim |= wd_last_u;
57	} else
58		wd_last_u = (utim & WD_INTERVAL);
59	if ((utim & WD_INTERVAL) == WD_TO_NEVER) {
60		utim = 0;
61
62		/* Assume all is well; watchdog signals failure. */
63		error = 0;
64	} else {
65		/* Assume no watchdog available; watchdog flags success */
66		error = EOPNOTSUPP;
67	}
68	EVENTHANDLER_INVOKE(watchdog_list, utim, &error);
69	return (error);
70}
71
72static int
73wd_ioctl(struct cdev *dev __unused, u_long cmd, caddr_t data,
74    int flags __unused, struct thread *td)
75{
76	u_int u;
77
78	if (cmd != WDIOCPATPAT)
79		return (ENOIOCTL);
80	u = *(u_int *)data;
81	if (u & ~(WD_ACTIVE | WD_PASSIVE | WD_LASTVAL | WD_INTERVAL))
82		return (EINVAL);
83	if ((u & (WD_ACTIVE | WD_PASSIVE)) == (WD_ACTIVE | WD_PASSIVE))
84		return (EINVAL);
85	if ((u & (WD_ACTIVE | WD_PASSIVE)) == 0 && ((u & WD_INTERVAL) > 0 ||
86	    (u & WD_LASTVAL) != 0))
87		return (EINVAL);
88	if (u & WD_PASSIVE)
89		return (ENOSYS);	/* XXX Not implemented yet */
90	u &= ~(WD_ACTIVE | WD_PASSIVE);
91
92	return (kern_do_pat(u));
93}
94
95u_int
96wdog_kern_last_timeout(void)
97{
98
99	return (wd_last_u);
100}
101
102int
103wdog_kern_pat(u_int utim)
104{
105
106	if (utim & ~(WD_LASTVAL | WD_INTERVAL))
107		return (EINVAL);
108
109	return (kern_do_pat(utim));
110}
111
112static struct cdevsw wd_cdevsw = {
113	.d_version =	D_VERSION,
114	.d_ioctl =	wd_ioctl,
115	.d_name =	"watchdog",
116};
117
118static int
119watchdog_modevent(module_t mod __unused, int type, void *data __unused)
120{
121	switch(type) {
122	case MOD_LOAD:
123		wd_dev = make_dev(&wd_cdevsw, 0,
124		    UID_ROOT, GID_WHEEL, 0600, _PATH_WATCHDOG);
125		return 0;
126	case MOD_UNLOAD:
127		destroy_dev(wd_dev);
128		return 0;
129	case MOD_SHUTDOWN:
130		return 0;
131	default:
132		return EOPNOTSUPP;
133	}
134}
135
136DEV_MODULE(watchdog, watchdog_modevent, NULL);
137