watchdog: bcm47xx_wdt.c: convert to watchdog core api

Convert the bcm47xx_wdt.c driver to the new watchdog core api.

The nowayout parameter is now added unconditionally to the module.
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>

drivers/watchdog/Kconfig

@@ -997,6 +997,7 @@ config ATH79_WDT
 config BCM47XX_WDT
 	tristate "Broadcom BCM47xx Watchdog Timer"
 	depends on BCM47XX
+	select WATCHDOG_CORE
 	help
 	  Hardware driver for the Broadcom BCM47xx Watchdog Timer.
 

drivers/watchdog/bcm47xx_wdt.c

@@ -14,15 +14,12 @@
 
 #include <linux/bitops.h>
 #include <linux/errno.h>
-#include <linux/fs.h>
 #include <linux/init.h>
 #include <linux/kernel.h>
-#include <linux/miscdevice.h>
 #include <linux/module.h>
 #include <linux/moduleparam.h>
 #include <linux/reboot.h>
 #include <linux/types.h>
-#include <linux/uaccess.h>
 #include <linux/watchdog.h>
 #include <linux/timer.h>
 #include <linux/jiffies.h>
@@ -41,15 +38,11 @@ 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, bool, 0);
 MODULE_PARM_DESC(nowayout,
 		"Watchdog cannot be stopped once started (default="
 				__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
-#endif
 
-static unsigned long bcm47xx_wdt_busy;
-static char expect_release;
 static struct timer_list wdt_timer;
 static atomic_t ticks;
 
@@ -97,29 +90,31 @@ static void bcm47xx_timer_tick(unsigned long unused)
 	}
 }
 
-static inline void bcm47xx_wdt_pet(void)
+static int bcm47xx_wdt_keepalive(struct watchdog_device *wdd)
 {
 	atomic_set(&ticks, wdt_time);
+
+	return 0;
 }
 
-static void bcm47xx_wdt_start(void)
+static int bcm47xx_wdt_start(struct watchdog_device *wdd)
 {
 	bcm47xx_wdt_pet();
 	bcm47xx_timer_tick(0);
+
+	return 0;
 }
 
-static void bcm47xx_wdt_pause(void)
+static int bcm47xx_wdt_stop(struct watchdog_device *wdd)
 {
 	del_timer_sync(&wdt_timer);
 	bcm47xx_wdt_hw_stop();
-}
 
-static void bcm47xx_wdt_stop(void)
-{
-	bcm47xx_wdt_pause();
+	return 0;
 }
 
-static int bcm47xx_wdt_settimeout(int new_time)
+static int bcm47xx_wdt_set_timeout(struct watchdog_device *wdd,
+				   unsigned int new_time)
 {
 	if ((new_time <= 0) || (new_time > WDT_MAX_TIME))
 		return -EINVAL;
@@ -128,51 +123,6 @@ static int bcm47xx_wdt_settimeout(int new_time)
 	return 0;
 }
 
-static int bcm47xx_wdt_open(struct inode *inode, struct file *file)
-{
-	if (test_and_set_bit(0, &bcm47xx_wdt_busy))
-		return -EBUSY;
-
-	bcm47xx_wdt_start();
-	return nonseekable_open(inode, file);
-}
-
-static int bcm47xx_wdt_release(struct inode *inode, struct file *file)
-{
-	if (expect_release == 42) {
-		bcm47xx_wdt_stop();
-	} else {
-		pr_crit("Unexpected close, not stopping watchdog!\n");
-		bcm47xx_wdt_start();
-	}
-
-	clear_bit(0, &bcm47xx_wdt_busy);
-	expect_release = 0;
-	return 0;
-}
-
-static ssize_t bcm47xx_wdt_write(struct file *file, const char __user *data,
-				size_t len, loff_t *ppos)
-{
-	if (len) {
-		if (!nowayout) {
-			size_t i;
-
-			expect_release = 0;
-
-			for (i = 0; i != len; i++) {
-				char c;
-				if (get_user(c, data + i))
-					return -EFAULT;
-				if (c == 'V')
-					expect_release = 42;
-			}
-		}
-		bcm47xx_wdt_pet();
-	}
-	return len;
-}
-
 static const struct watchdog_info bcm47xx_wdt_info = {
 	.identity	= DRV_NAME,
 	.options	= WDIOF_SETTIMEOUT |
@@ -180,80 +130,25 @@ static const struct watchdog_info bcm47xx_wdt_info = {
 				WDIOF_MAGICCLOSE,
 };
 
-static long bcm47xx_wdt_ioctl(struct file *file,
-					unsigned int cmd, unsigned long arg)
-{
-	void __user *argp = (void __user *)arg;
-	int __user *p = argp;
-	int new_value, retval = -EINVAL;
-
-	switch (cmd) {
-	case WDIOC_GETSUPPORT:
-		return copy_to_user(argp, &bcm47xx_wdt_info,
-				sizeof(bcm47xx_wdt_info)) ? -EFAULT : 0;
-
-	case WDIOC_GETSTATUS:
-	case WDIOC_GETBOOTSTATUS:
-		return put_user(0, p);
-
-	case WDIOC_SETOPTIONS:
-		if (get_user(new_value, p))
-			return -EFAULT;
-
-		if (new_value & WDIOS_DISABLECARD) {
-			bcm47xx_wdt_stop();
-			retval = 0;
-		}
-
-		if (new_value & WDIOS_ENABLECARD) {
-			bcm47xx_wdt_start();
-			retval = 0;
-		}
-
-		return retval;
-
-	case WDIOC_KEEPALIVE:
-		bcm47xx_wdt_pet();
-		return 0;
-
-	case WDIOC_SETTIMEOUT:
-		if (get_user(new_value, p))
-			return -EFAULT;
-
-		if (bcm47xx_wdt_settimeout(new_value))
-			return -EINVAL;
-
-		bcm47xx_wdt_pet();
-
-	case WDIOC_GETTIMEOUT:
-		return put_user(wdt_time, p);
-
-	default:
-		return -ENOTTY;
-	}
-}
-
 static int bcm47xx_wdt_notify_sys(struct notifier_block *this,
-	unsigned long code, void *unused)
+				  unsigned long code, void *unused)
 {
 	if (code == SYS_DOWN || code == SYS_HALT)
 		bcm47xx_wdt_stop();
 	return NOTIFY_DONE;
 }
 
-static const struct file_operations bcm47xx_wdt_fops = {
+static struct watchdog_ops bcm47xx_wdt_ops = {
 	.owner		= THIS_MODULE,
-	.llseek		= no_llseek,
-	.unlocked_ioctl	= bcm47xx_wdt_ioctl,
-	.open		= bcm47xx_wdt_open,
-	.release	= bcm47xx_wdt_release,
-	.write		= bcm47xx_wdt_write,
+	.start		= bcm47xx_wdt_start,
+	.stop		= bcm47xx_wdt_stop,
+	.ping		= bcm47xx_wdt_keepalive,
+	.set_timeout	= bcm47xx_wdt_set_timeout,
 };
 
-static struct miscdevice bcm47xx_wdt_miscdev = {
-	.minor		= WATCHDOG_MINOR,
-	.name		= "watchdog",
-	.fops		= &bcm47xx_wdt_fops,
+static struct watchdog_device bcm47xx_wdt_wdd = {
+	.info		= &bcm47xx_wdt_info,
+	.ops		= &bcm47xx_wdt_ops,
 };
 
 static struct notifier_block bcm47xx_wdt_notifier = {
@@ -274,12 +169,13 @@ static int __init bcm47xx_wdt_init(void)
 		pr_info("wdt_time value must be 0 < wdt_time < %d, using %d\n",
 			(WDT_MAX_TIME + 1), wdt_time);
 	}
+	watchdog_set_nowayout(&bcm47xx_wdt_wdd, nowayout);
 
 	ret = register_reboot_notifier(&bcm47xx_wdt_notifier);
 	if (ret)
 		return ret;
 
-	ret = misc_register(&bcm47xx_wdt_miscdev);
+	ret = watchdog_register_device(&bcm47xx_wdt_wdd);
 	if (ret) {
 		unregister_reboot_notifier(&bcm47xx_wdt_notifier);
 		return ret;
@@ -292,10 +188,7 @@ static int __init bcm47xx_wdt_init(void)
 
 static void __exit bcm47xx_wdt_exit(void)
 {
-	if (!nowayout)
-		bcm47xx_wdt_stop();
-
-	misc_deregister(&bcm47xx_wdt_miscdev);
+	watchdog_unregister_device(&bcm47xx_wdt_wdd);
 
 	unregister_reboot_notifier(&bcm47xx_wdt_notifier);
 }
@@ -306,4 +199,3 @@ module_exit(bcm47xx_wdt_exit);
 MODULE_AUTHOR("Aleksandar Radovanovic");
 MODULE_DESCRIPTION("Watchdog driver for Broadcom BCM47xx");
 MODULE_LICENSE("GPL");
-MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);