1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Watchdog Driver Test Program
4  */
5 
6 #include <errno.h>
7 #include <stdio.h>
8 #include <stdlib.h>
9 #include <string.h>
10 #include <unistd.h>
11 #include <fcntl.h>
12 #include <signal.h>
13 #include <getopt.h>
14 #include <sys/ioctl.h>
15 #include <linux/types.h>
16 #include <linux/watchdog.h>
17 
18 #define DEFAULT_PING_RATE	1
19 
20 int fd;
21 const char v = 'V';
22 static const char sopts[] = "bdehp:t:Tn:NL";
23 static const struct option lopts[] = {
24 	{"bootstatus",          no_argument, NULL, 'b'},
25 	{"disable",             no_argument, NULL, 'd'},
26 	{"enable",              no_argument, NULL, 'e'},
27 	{"help",                no_argument, NULL, 'h'},
28 	{"pingrate",      required_argument, NULL, 'p'},
29 	{"timeout",       required_argument, NULL, 't'},
30 	{"gettimeout",          no_argument, NULL, 'T'},
31 	{"pretimeout",    required_argument, NULL, 'n'},
32 	{"getpretimeout",       no_argument, NULL, 'N'},
33 	{"gettimeleft",		no_argument, NULL, 'L'},
34 	{NULL,                  no_argument, NULL, 0x0}
35 };
36 
37 /*
38  * This function simply sends an IOCTL to the driver, which in turn ticks
39  * the PC Watchdog card to reset its internal timer so it doesn't trigger
40  * a computer reset.
41  */
42 static void keep_alive(void)
43 {
44 	int dummy;
45 	int ret;
46 
47 	ret = ioctl(fd, WDIOC_KEEPALIVE, &dummy);
48 	if (!ret)
49 		printf(".");
50 }
51 
52 /*
53  * The main program.  Run the program with "-d" to disable the card,
54  * or "-e" to enable the card.
55  */
56 
57 static void term(int sig)
58 {
59 	int ret = write(fd, &v, 1);
60 
61 	close(fd);
62 	if (ret < 0)
63 		printf("\nStopping watchdog ticks failed (%d)...\n", errno);
64 	else
65 		printf("\nStopping watchdog ticks...\n");
66 	exit(0);
67 }
68 
69 static void usage(char *progname)
70 {
71 	printf("Usage: %s [options]\n", progname);
72 	printf(" -b, --bootstatus    Get last boot status (Watchdog/POR)\n");
73 	printf(" -d, --disable       Turn off the watchdog timer\n");
74 	printf(" -e, --enable        Turn on the watchdog timer\n");
75 	printf(" -h, --help          Print the help message\n");
76 	printf(" -p, --pingrate=P    Set ping rate to P seconds (default %d)\n", DEFAULT_PING_RATE);
77 	printf(" -t, --timeout=T     Set timeout to T seconds\n");
78 	printf(" -T, --gettimeout    Get the timeout\n");
79 	printf(" -n, --pretimeout=T  Set the pretimeout to T seconds\n");
80 	printf(" -N, --getpretimeout Get the pretimeout\n");
81 	printf(" -L, --gettimeleft   Get the time left until timer expires\n");
82 	printf("\n");
83 	printf("Parameters are parsed left-to-right in real-time.\n");
84 	printf("Example: %s -d -t 10 -p 5 -e\n", progname);
85 	printf("Example: %s -t 12 -T -n 7 -N\n", progname);
86 }
87 
88 int main(int argc, char *argv[])
89 {
90 	int flags;
91 	unsigned int ping_rate = DEFAULT_PING_RATE;
92 	int ret;
93 	int c;
94 	int oneshot = 0;
95 
96 	setbuf(stdout, NULL);
97 
98 	fd = open("/dev/watchdog", O_WRONLY);
99 
100 	if (fd == -1) {
101 		if (errno == ENOENT)
102 			printf("Watchdog device not enabled.\n");
103 		else if (errno == EACCES)
104 			printf("Run watchdog as root.\n");
105 		else
106 			printf("Watchdog device open failed %s\n",
107 				strerror(errno));
108 		exit(-1);
109 	}
110 
111 	while ((c = getopt_long(argc, argv, sopts, lopts, NULL)) != -1) {
112 		switch (c) {
113 		case 'b':
114 			flags = 0;
115 			oneshot = 1;
116 			ret = ioctl(fd, WDIOC_GETBOOTSTATUS, &flags);
117 			if (!ret)
118 				printf("Last boot is caused by: %s.\n", (flags != 0) ?
119 					"Watchdog" : "Power-On-Reset");
120 			else
121 				printf("WDIOC_GETBOOTSTATUS error '%s'\n", strerror(errno));
122 			break;
123 		case 'd':
124 			flags = WDIOS_DISABLECARD;
125 			ret = ioctl(fd, WDIOC_SETOPTIONS, &flags);
126 			if (!ret)
127 				printf("Watchdog card disabled.\n");
128 			else {
129 				printf("WDIOS_DISABLECARD error '%s'\n", strerror(errno));
130 				oneshot = 1;
131 			}
132 			break;
133 		case 'e':
134 			flags = WDIOS_ENABLECARD;
135 			ret = ioctl(fd, WDIOC_SETOPTIONS, &flags);
136 			if (!ret)
137 				printf("Watchdog card enabled.\n");
138 			else {
139 				printf("WDIOS_ENABLECARD error '%s'\n", strerror(errno));
140 				oneshot = 1;
141 			}
142 			break;
143 		case 'p':
144 			ping_rate = strtoul(optarg, NULL, 0);
145 			if (!ping_rate)
146 				ping_rate = DEFAULT_PING_RATE;
147 			printf("Watchdog ping rate set to %u seconds.\n", ping_rate);
148 			break;
149 		case 't':
150 			flags = strtoul(optarg, NULL, 0);
151 			ret = ioctl(fd, WDIOC_SETTIMEOUT, &flags);
152 			if (!ret)
153 				printf("Watchdog timeout set to %u seconds.\n", flags);
154 			else {
155 				printf("WDIOC_SETTIMEOUT error '%s'\n", strerror(errno));
156 				oneshot = 1;
157 			}
158 			break;
159 		case 'T':
160 			oneshot = 1;
161 			ret = ioctl(fd, WDIOC_GETTIMEOUT, &flags);
162 			if (!ret)
163 				printf("WDIOC_GETTIMEOUT returns %u seconds.\n", flags);
164 			else
165 				printf("WDIOC_GETTIMEOUT error '%s'\n", strerror(errno));
166 			break;
167 		case 'n':
168 			flags = strtoul(optarg, NULL, 0);
169 			ret = ioctl(fd, WDIOC_SETPRETIMEOUT, &flags);
170 			if (!ret)
171 				printf("Watchdog pretimeout set to %u seconds.\n", flags);
172 			else {
173 				printf("WDIOC_SETPRETIMEOUT error '%s'\n", strerror(errno));
174 				oneshot = 1;
175 			}
176 			break;
177 		case 'N':
178 			oneshot = 1;
179 			ret = ioctl(fd, WDIOC_GETPRETIMEOUT, &flags);
180 			if (!ret)
181 				printf("WDIOC_GETPRETIMEOUT returns %u seconds.\n", flags);
182 			else
183 				printf("WDIOC_GETPRETIMEOUT error '%s'\n", strerror(errno));
184 			break;
185 		case 'L':
186 			oneshot = 1;
187 			ret = ioctl(fd, WDIOC_GETTIMELEFT, &flags);
188 			if (!ret)
189 				printf("WDIOC_GETTIMELEFT returns %u seconds.\n", flags);
190 			else
191 				printf("WDIOC_GETTIMELEFT error '%s'\n", strerror(errno));
192 			break;
193 
194 		default:
195 			usage(argv[0]);
196 			goto end;
197 		}
198 	}
199 
200 	if (oneshot)
201 		goto end;
202 
203 	printf("Watchdog Ticking Away!\n");
204 
205 	signal(SIGINT, term);
206 
207 	while (1) {
208 		keep_alive();
209 		sleep(ping_rate);
210 	}
211 end:
212 	ret = write(fd, &v, 1);
213 	if (ret < 0)
214 		printf("Stopping watchdog ticks failed (%d)...\n", errno);
215 	close(fd);
216 	return 0;
217 }
218