Merge master.kernel.org:/pub/scm/linux/kernel/git/wim/linux-2.6-watchdog

* master.kernel.org:/pub/scm/linux/kernel/git/wim/linux-2.6-watchdog:
  [WATCHDOG] Documentation/watchdog update
  [WATCHDOG] convert AT91RM9200 watchdog to platform driver
  [WATCHDOG] add WDIOC_GETTIMELEFT ioctl
  [WATCHDOG] Pre-Timeout flags

Documentation/watchdog/pcwd-watchdog.txt

@@ -22,78 +22,9 @@
  to run the program with an "&" to run it in the background!)
 
  If you want to write a program to be compatible with the PC Watchdog
- driver, simply do the following:
-
--- Snippet of code --
-/*
- * 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);
-    }
-}
--- End snippet --
+ driver, simply use of modify the watchdog test program:
+ Documentation/watchdog/src/watchdog-test.c
+
 
  Other IOCTL functions include:
 

Documentation/watchdog/src/watchdog-simple.c

+#include <stdlib.h>
+#include <fcntl.h>
+
+int main(int argc, const char *argv[]) {
+	int fd = open("/dev/watchdog", O_WRONLY);
+	if (fd == -1) {
+		perror("watchdog");
+		exit(1);
+	}
+	while (1) {
+		write(fd, "\0", 1);
+		fsync(fd);
+		sleep(10);
+	}
+}

Documentation/watchdog/src/watchdog-test.c

+/*
+ * 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);
+    }
+}

Documentation/watchdog/watchdog-api.txt

@@ -34,22 +34,7 @@ activates as soon as /dev/watchdog is opened and will reboot unless
 the watchdog is pinged within a certain time, this time is called the
 timeout or margin.  The simplest way to ping the watchdog is to write
 some data to the device.  So a very simple watchdog daemon would look
-like this:
-
-#include <stdlib.h>
-#include <fcntl.h>
-
-int main(int argc, const char *argv[]) {
-	int fd=open("/dev/watchdog",O_WRONLY);
-	if (fd==-1) {
-		perror("watchdog");
-		exit(1);
-	}
-	while(1) {
-		write(fd, "\0", 1);
-		sleep(10);
-	}
-}
+like this source file:  see Documentation/watchdog/src/watchdog-simple.c
 
 A more advanced driver could for example check that a HTTP server is
 still responding before doing the write call to ping the watchdog.
@@ -110,7 +95,40 @@ current timeout using the GETTIMEOUT ioctl.
     ioctl(fd, WDIOC_GETTIMEOUT, &timeout);
     printf("The timeout was is %d seconds\n", timeout);
 
-Envinronmental monitoring:
+Pretimeouts:
+
+Some watchdog timers can be set to have a trigger go off before the
+actual time they will reset the system.  This can be done with an NMI,
+interrupt, or other mechanism.  This allows Linux to record useful
+information (like panic information and kernel coredumps) before it
+resets.
+
+    pretimeout = 10;
+    ioctl(fd, WDIOC_SETPRETIMEOUT, &pretimeout);
+
+Note that the pretimeout is the number of seconds before the time
+when the timeout will go off.  It is not the number of seconds until
+the pretimeout.  So, for instance, if you set the timeout to 60 seconds
+and the pretimeout to 10 seconds, the pretimout will go of in 50
+seconds.  Setting a pretimeout to zero disables it.
+
+There is also a get function for getting the pretimeout:
+
+    ioctl(fd, WDIOC_GETPRETIMEOUT, &timeout);
+    printf("The pretimeout was is %d seconds\n", timeout);
+
+Not all watchdog drivers will support a pretimeout.
+
+Get the number of seconds before reboot:
+
+Some watchdog drivers have the ability to report the remaining time
+before the system will reboot. The WDIOC_GETTIMELEFT is the ioctl
+that returns the number of seconds before reboot.
+
+    ioctl(fd, WDIOC_GETTIMELEFT, &timeleft);
+    printf("The timeout was is %d seconds\n", timeleft);
+
+Environmental monitoring:
 
 All watchdog drivers are required return more information about the system,
 some do temperature, fan and power level monitoring, some can tell you
@@ -169,6 +187,10 @@ The watchdog saw a keepalive ping since it was last queried.
 
 	WDIOF_SETTIMEOUT	Can set/get the timeout
 
+The watchdog can do pretimeouts.
+
+	WDIOF_PRETIMEOUT	Pretimeout (in seconds), get/set
+
 
 For those drivers that return any bits set in the option field, the
 GETSTATUS and GETBOOTSTATUS ioctls can be used to ask for the current

Documentation/watchdog/watchdog.txt

@@ -65,28 +65,7 @@ The external event interfaces on the WDT boards are not currently supported.
 Minor numbers are however allocated for it.
 
 
-Example Watchdog Driver
------------------------
-
-#include <stdio.h>
-#include <unistd.h>
-#include <fcntl.h>
-
-int main(int argc, const char *argv[])
-{
-	int fd=open("/dev/watchdog",O_WRONLY);
-	if(fd==-1)
-	{
-		perror("watchdog");
-		exit(1);
-	}
-	while(1)
-	{
-		write(fd,"\0",1);
-		fsync(fd);
-		sleep(10);
-	}
-}
+Example Watchdog Driver:  see Documentation/watchdog/src/watchdog-simple.c
 
 
 Contact Information

drivers/char/watchdog/at91_wdt.c

@@ -17,14 +17,15 @@
 #include <linux/miscdevice.h>
 #include <linux/module.h>
 #include <linux/moduleparam.h>
+#include <linux/platform_device.h>
 #include <linux/types.h>
 #include <linux/watchdog.h>
 #include <asm/bitops.h>
 #include <asm/uaccess.h>
 
 
-#define WDT_DEFAULT_TIME	5	/* 5 seconds */
-#define WDT_MAX_TIME		256	/* 256 seconds */
+#define WDT_DEFAULT_TIME	5	/* seconds */
+#define WDT_MAX_TIME		256	/* seconds */
 
 static int wdt_time = WDT_DEFAULT_TIME;
 static int nowayout = WATCHDOG_NOWAYOUT;
@@ -32,8 +33,10 @@ static int nowayout = WATCHDOG_NOWAYOUT;
 module_param(wdt_time, int, 0);
 MODULE_PARM_DESC(wdt_time, "Watchdog time in seconds. (default="__MODULE_STRING(WDT_DEFAULT_TIME) ")");
 
+#ifdef CONFIG_WATCHDOG_NOWAYOUT
 module_param(nowayout, int, 0);
 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
+#endif
 
 
 static unsigned long at91wdt_busy;
@@ -196,27 +199,84 @@ static struct miscdevice at91wdt_miscdev = {
 	.fops		= &at91wdt_fops,
 };
 
-static int __init at91_wdt_init(void)
+static int __init at91wdt_probe(struct platform_device *pdev)
 {
 	int res;
 
-	/* Check that the heartbeat value is within range; if not reset to the default */
-	if (at91_wdt_settimeout(wdt_time)) {
-		at91_wdt_settimeout(WDT_DEFAULT_TIME);
-		printk(KERN_INFO "at91_wdt: wdt_time value must be 1 <= wdt_time <= 256, using %d\n", wdt_time);
-	}
+	if (at91wdt_miscdev.dev)
+		return -EBUSY;
+	at91wdt_miscdev.dev = &pdev->dev;
 
 	res = misc_register(&at91wdt_miscdev);
 	if (res)
 		return res;
 
-	printk("AT91 Watchdog Timer enabled (%d seconds, nowayout=%d)\n", wdt_time, nowayout);
+	printk("AT91 Watchdog Timer enabled (%d seconds%s)\n", wdt_time, nowayout ? ", nowayout" : "");
+	return 0;
+}
+
+static int __exit at91wdt_remove(struct platform_device *pdev)
+{
+	int res;
+
+	res = misc_deregister(&at91wdt_miscdev);
+	if (!res)
+		at91wdt_miscdev.dev = NULL;
+
+	return res;
+}
+
+static void at91wdt_shutdown(struct platform_device *pdev)
+{
+	at91_wdt_stop();
+}
+
+#ifdef CONFIG_PM
+
+static int at91wdt_suspend(struct platform_device *pdev, pm_message_t message)
+{
+	at91_wdt_stop();
+	return 0;
+}
+
+static int at91wdt_resume(struct platform_device *pdev)
+{
+	if (at91wdt_busy)
+		at91_wdt_start();
 		return 0;
 }
 
+#else
+#define at91wdt_suspend NULL
+#define at91wdt_resume	NULL
+#endif
+
+static struct platform_driver at91wdt_driver = {
+	.probe		= at91wdt_probe,
+	.remove		= __exit_p(at91wdt_remove),
+	.shutdown	= at91wdt_shutdown,
+	.suspend	= at91wdt_suspend,
+	.resume		= at91wdt_resume,
+	.driver		= {
+		.name	= "at91_wdt",
+		.owner	= THIS_MODULE,
+	},
+};
+
+static int __init at91_wdt_init(void)
+{
+	/* Check that the heartbeat value is within range; if not reset to the default */
+	if (at91_wdt_settimeout(wdt_time)) {
+		at91_wdt_settimeout(WDT_DEFAULT_TIME);
+		pr_info("at91_wdt: wdt_time value must be 1 <= wdt_time <= 256, using %d\n", wdt_time);
+	}
+
+	return platform_driver_register(&at91wdt_driver);
+}
+
 static void __exit at91_wdt_exit(void)
 {
-	misc_deregister(&at91wdt_miscdev);
+	platform_driver_unregister(&at91wdt_driver);
 }
 
 module_init(at91_wdt_init);

drivers/char/watchdog/i8xx_tco.c

@@ -205,6 +205,23 @@ static int tco_timer_set_heartbeat (int t)
 	return 0;
 }
 
+static int tco_timer_get_timeleft (int *time_left)
+{
+	unsigned char val;
+
+	spin_lock(&tco_lock);
+
+	/* read the TCO Timer */
+	val = inb (TCO1_RLD);
+	val &= 0x3f;
+
+	spin_unlock(&tco_lock);
+
+	*time_left = (int)((val * 6) / 10);
+
+	return 0;
+}
+
 /*
  *	/dev/watchdog handling
  */
@@ -272,6 +289,7 @@ static int i8xx_tco_ioctl (struct inode *inode, struct file *file,
 {
 	int new_options, retval = -EINVAL;
 	int new_heartbeat;
+	int time_left;
 	void __user *argp = (void __user *)arg;
 	int __user *p = argp;
 	static struct watchdog_info ident = {
@@ -329,6 +347,14 @@ static int i8xx_tco_ioctl (struct inode *inode, struct file *file,
 		case WDIOC_GETTIMEOUT:
 			return put_user(heartbeat, p);
 
+		case WDIOC_GETTIMELEFT:
+		{
+			if (tco_timer_get_timeleft(&time_left))
+				return -EINVAL;
+
+			return put_user(time_left, p);
+		}
+
 		default:
 			return -ENOIOCTLCMD;
 	}

drivers/char/watchdog/pcwd_pci.c

@@ -390,6 +390,24 @@ static int pcipcwd_get_temperature(int *temperature)
 	return 0;
 }
 
+static int pcipcwd_get_timeleft(int *time_left)
+{
+	int msb;
+	int lsb;
+
+	/* Read the time that's left before rebooting */
+	/* Note: if the board is not yet armed then we will read 0xFFFF */
+	send_command(CMD_READ_WATCHDOG_TIMEOUT, &msb, &lsb);
+
+	*time_left = (msb << 8) + lsb;
+
+	if (debug >= VERBOSE)
+		printk(KERN_DEBUG PFX "Time left before next reboot: %d\n",
+		       *time_left);
+
+	return 0;
+}
+
 /*
  *	/dev/watchdog handling
  */
@@ -512,6 +530,16 @@ static int pcipcwd_ioctl(struct inode *inode, struct file *file,
 		case WDIOC_GETTIMEOUT:
 			return put_user(heartbeat, p);
 
+		case WDIOC_GETTIMELEFT:
+		{
+			int time_left;
+
+			if (pcipcwd_get_timeleft(&time_left))
+				return -EFAULT;
+
+			return put_user(time_left, p);
+		}
+
 		default:
 			return -ENOIOCTLCMD;
 	}

drivers/char/watchdog/pcwd_usb.c

@@ -317,6 +317,19 @@ static int usb_pcwd_get_temperature(struct usb_pcwd_private *usb_pcwd, int *temp
 	return 0;
 }
 
+static int usb_pcwd_get_timeleft(struct usb_pcwd_private *usb_pcwd, int *time_left)
+{
+	unsigned char msb, lsb;
+
+	/* Read the time that's left before rebooting */
+	/* Note: if the board is not yet armed then we will read 0xFFFF */
+	usb_pcwd_send_command(usb_pcwd, CMD_READ_WATCHDOG_TIMEOUT, &msb, &lsb);
+
+	*time_left = (msb << 8) + lsb;
+
+	return 0;
+}
+
 /*
  *	/dev/watchdog handling
  */
@@ -422,6 +435,16 @@ static int usb_pcwd_ioctl(struct inode *inode, struct file *file,
 		case WDIOC_GETTIMEOUT:
 			return put_user(heartbeat, p);
 
+		case WDIOC_GETTIMELEFT:
+		{
+			int time_left;
+
+			if (usb_pcwd_get_timeleft(usb_pcwd_device, &time_left))
+				return -EFAULT;
+
+			return put_user(time_left, p);
+		}
+
 		default:
 			return -ENOIOCTLCMD;
 	}

include/linux/watchdog.h

@@ -28,6 +28,9 @@ struct watchdog_info {
 #define	WDIOC_KEEPALIVE		_IOR(WATCHDOG_IOCTL_BASE, 5, int)
 #define	WDIOC_SETTIMEOUT        _IOWR(WATCHDOG_IOCTL_BASE, 6, int)
 #define	WDIOC_GETTIMEOUT        _IOR(WATCHDOG_IOCTL_BASE, 7, int)
+#define	WDIOC_SETPRETIMEOUT	_IOWR(WATCHDOG_IOCTL_BASE, 8, int)
+#define	WDIOC_GETPRETIMEOUT	_IOR(WATCHDOG_IOCTL_BASE, 9, int)
+#define	WDIOC_GETTIMELEFT	_IOR(WATCHDOG_IOCTL_BASE, 10, int)
 
 #define	WDIOF_UNKNOWN		-1	/* Unknown flag error */
 #define	WDIOS_UNKNOWN		-1	/* Unknown status error */
@@ -41,6 +44,7 @@ struct watchdog_info {
 #define	WDIOF_POWEROVER		0x0040	/* Power over voltage */
 #define	WDIOF_SETTIMEOUT	0x0080  /* Set timeout (in seconds) */
 #define	WDIOF_MAGICCLOSE	0x0100	/* Supports magic close char */
+#define	WDIOF_PRETIMEOUT	0x0200  /* Pretimeout (in seconds), get/set */
 #define	WDIOF_KEEPALIVEPING	0x8000	/* Keep alive ping reply */
 
 #define	WDIOS_DISABLECARD	0x0001	/* Turn off the watchdog timer */