4 files changed, 105 insertions, 0 deletions
diff --git a/Documentation/watchdog/src/.gitignore b/Documentation/watchdog/src/.gitignore
new file mode 100644
index 0000000..ac90997
--- /dev/null
+++ b/Documentation/watchdog/src/.gitignore
@@ -0,0 +1,2 @@
+watchdog-simple
+watchdog-test
diff --git a/Documentation/watchdog/src/Makefile b/Documentation/watchdog/src/Makefile
new file mode 100644
index 0000000..40e5f46
--- /dev/null
+++ b/Documentation/watchdog/src/Makefile
@@ -0,0 +1,8 @@
+# kbuild trick to avoid linker error. Can be omitted if a module is built.
+obj- := dummy.o
+
+# List of programs to build
+hostprogs-y := watchdog-simple watchdog-test
+
+# Tell kbuild to always build the programs
+always := $(hostprogs-y)
diff --git a/Documentation/watchdog/src/watchdog-simple.c b/Documentation/watchdog/src/watchdog-simple.c
new file mode 100644
index 0000000..4cf72f3
--- /dev/null
+++ b/Documentation/watchdog/src/watchdog-simple.c
@@ -0,0 +1,27 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+
+int main(void)
+{
+	int fd = open("/dev/watchdog", O_WRONLY);
+	int ret = 0;
+	if (fd == -1) {
+		perror("watchdog");
+		exit(EXIT_FAILURE);
+	}
+	while (1) {
+		ret = write(fd, "\0", 1);
+		if (ret != 1) {
+			ret = -1;
+			break;
+		}
+		ret = fsync(fd);
+		if (ret)
+			break;
+		sleep(10);
+	}
+	close(fd);
+	return ret;
+}
diff --git a/Documentation/watchdog/src/watchdog-test.c b/Documentation/watchdog/src/watchdog-test.c
new file mode 100644
index 0000000..65f6c19
--- /dev/null
+++ b/Documentation/watchdog/src/watchdog-test.c
@@ -0,0 +1,68 @@
+/*
+ * Watchdog Driver Test Program
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/ioctl.h>
+#include <linux/types.h>
+#include <linux/watchdog.h>
+
+int fd;
+
+/*
+ * This function simply sends an IOCTL to the driver, which in turn ticks
+ * the PC Watchdog card to reset its internal timer so it doesn't trigger
+ * a computer reset.
+ */
+void keep_alive(void)
+{
+    int dummy;
+
+    ioctl(fd, WDIOC_KEEPALIVE, &dummy);
+}
+
+/*
+ * The main program.  Run the program with "-d" to disable the card,
+ * or "-e" to enable the card.
+ */
+int main(int argc, char *argv[])
+{
+    fd = open("/dev/watchdog", O_WRONLY);
+
+    if (fd == -1) {
+	fprintf(stderr, "Watchdog device not enabled.\n");
+	fflush(stderr);
+	exit(-1);
+    }
+
+    if (argc > 1) {
+	if (!strncasecmp(argv[1], "-d", 2)) {
+	    ioctl(fd, WDIOC_SETOPTIONS, WDIOS_DISABLECARD);
+	    fprintf(stderr, "Watchdog card disabled.\n");
+	    fflush(stderr);
+	    exit(0);
+	} else if (!strncasecmp(argv[1], "-e", 2)) {
+	    ioctl(fd, WDIOC_SETOPTIONS, WDIOS_ENABLECARD);
+	    fprintf(stderr, "Watchdog card enabled.\n");
+	    fflush(stderr);
+	    exit(0);
+	} else {
+	    fprintf(stderr, "-d to disable, -e to enable.\n");
+	    fprintf(stderr, "run by itself to tick the card.\n");
+	    fflush(stderr);
+	    exit(0);
+	}
+    } else {
+	fprintf(stderr, "Watchdog Ticking Away!\n");
+	fflush(stderr);
+    }
+
+    while(1) {
+	keep_alive();
+	sleep(1);
+    }
+}