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-rw-r--r--Documentation/watchdog/pcwd-watchdog.txt75
-rw-r--r--Documentation/watchdog/src/watchdog-simple.c15
-rw-r--r--Documentation/watchdog/src/watchdog-test.c68
-rw-r--r--Documentation/watchdog/watchdog-api.txt17
-rw-r--r--Documentation/watchdog/watchdog.txt23
5 files changed, 88 insertions, 110 deletions
diff --git a/Documentation/watchdog/pcwd-watchdog.txt b/Documentation/watchdog/pcwd-watchdog.txt
index 12187a33e310..d9ee6336c1d4 100644
--- a/Documentation/watchdog/pcwd-watchdog.txt
+++ b/Documentation/watchdog/pcwd-watchdog.txt
@@ -22,78 +22,9 @@
22 to run the program with an "&" to run it in the background!) 22 to run the program with an "&" to run it in the background!)
23 23
24 If you want to write a program to be compatible with the PC Watchdog 24 If you want to write a program to be compatible with the PC Watchdog
25 driver, simply do the following: 25 driver, simply use of modify the watchdog test program:
26 26 Documentation/watchdog/src/watchdog-test.c
27-- Snippet of code -- 27
28/*
29 * Watchdog Driver Test Program
30 */
31
32#include <stdio.h>
33#include <stdlib.h>
34#include <string.h>
35#include <unistd.h>
36#include <fcntl.h>
37#include <sys/ioctl.h>
38#include <linux/types.h>
39#include <linux/watchdog.h>
40
41int fd;
42
43/*
44 * This function simply sends an IOCTL to the driver, which in turn ticks
45 * the PC Watchdog card to reset its internal timer so it doesn't trigger
46 * a computer reset.
47 */
48void keep_alive(void)
49{
50 int dummy;
51
52 ioctl(fd, WDIOC_KEEPALIVE, &dummy);
53}
54
55/*
56 * The main program. Run the program with "-d" to disable the card,
57 * or "-e" to enable the card.
58 */
59int main(int argc, char *argv[])
60{
61 fd = open("/dev/watchdog", O_WRONLY);
62
63 if (fd == -1) {
64 fprintf(stderr, "Watchdog device not enabled.\n");
65 fflush(stderr);
66 exit(-1);
67 }
68
69 if (argc > 1) {
70 if (!strncasecmp(argv[1], "-d", 2)) {
71 ioctl(fd, WDIOC_SETOPTIONS, WDIOS_DISABLECARD);
72 fprintf(stderr, "Watchdog card disabled.\n");
73 fflush(stderr);
74 exit(0);
75 } else if (!strncasecmp(argv[1], "-e", 2)) {
76 ioctl(fd, WDIOC_SETOPTIONS, WDIOS_ENABLECARD);
77 fprintf(stderr, "Watchdog card enabled.\n");
78 fflush(stderr);
79 exit(0);
80 } else {
81 fprintf(stderr, "-d to disable, -e to enable.\n");
82 fprintf(stderr, "run by itself to tick the card.\n");
83 fflush(stderr);
84 exit(0);
85 }
86 } else {
87 fprintf(stderr, "Watchdog Ticking Away!\n");
88 fflush(stderr);
89 }
90
91 while(1) {
92 keep_alive();
93 sleep(1);
94 }
95}
96-- End snippet --
97 28
98 Other IOCTL functions include: 29 Other IOCTL functions include:
99 30
diff --git a/Documentation/watchdog/src/watchdog-simple.c b/Documentation/watchdog/src/watchdog-simple.c
new file mode 100644
index 000000000000..85cf17c48669
--- /dev/null
+++ b/Documentation/watchdog/src/watchdog-simple.c
@@ -0,0 +1,15 @@
1#include <stdlib.h>
2#include <fcntl.h>
3
4int main(int argc, const char *argv[]) {
5 int fd = open("/dev/watchdog", O_WRONLY);
6 if (fd == -1) {
7 perror("watchdog");
8 exit(1);
9 }
10 while (1) {
11 write(fd, "\0", 1);
12 fsync(fd);
13 sleep(10);
14 }
15}
diff --git a/Documentation/watchdog/src/watchdog-test.c b/Documentation/watchdog/src/watchdog-test.c
new file mode 100644
index 000000000000..65f6c19cb865
--- /dev/null
+++ b/Documentation/watchdog/src/watchdog-test.c
@@ -0,0 +1,68 @@
1/*
2 * Watchdog Driver Test Program
3 */
4
5#include <stdio.h>
6#include <stdlib.h>
7#include <string.h>
8#include <unistd.h>
9#include <fcntl.h>
10#include <sys/ioctl.h>
11#include <linux/types.h>
12#include <linux/watchdog.h>
13
14int fd;
15
16/*
17 * This function simply sends an IOCTL to the driver, which in turn ticks
18 * the PC Watchdog card to reset its internal timer so it doesn't trigger
19 * a computer reset.
20 */
21void keep_alive(void)
22{
23 int dummy;
24
25 ioctl(fd, WDIOC_KEEPALIVE, &dummy);
26}
27
28/*
29 * The main program. Run the program with "-d" to disable the card,
30 * or "-e" to enable the card.
31 */
32int main(int argc, char *argv[])
33{
34 fd = open("/dev/watchdog", O_WRONLY);
35
36 if (fd == -1) {
37 fprintf(stderr, "Watchdog device not enabled.\n");
38 fflush(stderr);
39 exit(-1);
40 }
41
42 if (argc > 1) {
43 if (!strncasecmp(argv[1], "-d", 2)) {
44 ioctl(fd, WDIOC_SETOPTIONS, WDIOS_DISABLECARD);
45 fprintf(stderr, "Watchdog card disabled.\n");
46 fflush(stderr);
47 exit(0);
48 } else if (!strncasecmp(argv[1], "-e", 2)) {
49 ioctl(fd, WDIOC_SETOPTIONS, WDIOS_ENABLECARD);
50 fprintf(stderr, "Watchdog card enabled.\n");
51 fflush(stderr);
52 exit(0);
53 } else {
54 fprintf(stderr, "-d to disable, -e to enable.\n");
55 fprintf(stderr, "run by itself to tick the card.\n");
56 fflush(stderr);
57 exit(0);
58 }
59 } else {
60 fprintf(stderr, "Watchdog Ticking Away!\n");
61 fflush(stderr);
62 }
63
64 while(1) {
65 keep_alive();
66 sleep(1);
67 }
68}
diff --git a/Documentation/watchdog/watchdog-api.txt b/Documentation/watchdog/watchdog-api.txt
index d738ec25eaa4..958ff3d48be3 100644
--- a/Documentation/watchdog/watchdog-api.txt
+++ b/Documentation/watchdog/watchdog-api.txt
@@ -34,22 +34,7 @@ activates as soon as /dev/watchdog is opened and will reboot unless
34the watchdog is pinged within a certain time, this time is called the 34the watchdog is pinged within a certain time, this time is called the
35timeout or margin. The simplest way to ping the watchdog is to write 35timeout or margin. The simplest way to ping the watchdog is to write
36some data to the device. So a very simple watchdog daemon would look 36some data to the device. So a very simple watchdog daemon would look
37like this: 37like this source file: see Documentation/watchdog/src/watchdog-simple.c
38
39#include <stdlib.h>
40#include <fcntl.h>
41
42int main(int argc, const char *argv[]) {
43 int fd=open("/dev/watchdog",O_WRONLY);
44 if (fd==-1) {
45 perror("watchdog");
46 exit(1);
47 }
48 while(1) {
49 write(fd, "\0", 1);
50 sleep(10);
51 }
52}
53 38
54A more advanced driver could for example check that a HTTP server is 39A more advanced driver could for example check that a HTTP server is
55still responding before doing the write call to ping the watchdog. 40still responding before doing the write call to ping the watchdog.
diff --git a/Documentation/watchdog/watchdog.txt b/Documentation/watchdog/watchdog.txt
index dffda29c8799..4b1ff69cc19a 100644
--- a/Documentation/watchdog/watchdog.txt
+++ b/Documentation/watchdog/watchdog.txt
@@ -65,28 +65,7 @@ The external event interfaces on the WDT boards are not currently supported.
65Minor numbers are however allocated for it. 65Minor numbers are however allocated for it.
66 66
67 67
68Example Watchdog Driver 68Example Watchdog Driver: see Documentation/watchdog/src/watchdog-simple.c
69-----------------------
70
71#include <stdio.h>
72#include <unistd.h>
73#include <fcntl.h>
74
75int main(int argc, const char *argv[])
76{
77 int fd=open("/dev/watchdog",O_WRONLY);
78 if(fd==-1)
79 {
80 perror("watchdog");
81 exit(1);
82 }
83 while(1)
84 {
85 write(fd,"\0",1);
86 fsync(fd);
87 sleep(10);
88 }
89}
90 69
91 70
92Contact Information 71Contact Information