watchdog: Use static struct class watchdog_class in stead of pointer

We need few sysfs attributes to know different status of a watchdog device.
To do that, we need to associate .dev_groups with watchdog_class. So
convert it from pointer to static.
Putting this static struct in watchdog_dev.c, so that static device
attributes defined in that file can be attached to it.

Signed-off-by: Pratyush Anand <panand@redhat.com>
Suggested-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>

drivers/watchdog/watchdog_core.c

@@ -370,19 +370,9 @@ static int __init watchdog_deferred_registration(void)
 
 static int __init watchdog_init(void)
 {
-	int err;
-
-	watchdog_class = class_create(THIS_MODULE, "watchdog");
-	if (IS_ERR(watchdog_class)) {
-		pr_err("couldn't create class\n");
+	watchdog_class = watchdog_dev_init();
+	if (IS_ERR(watchdog_class))
 		return PTR_ERR(watchdog_class);
-	}
-
-	err = watchdog_dev_init();
-	if (err < 0) {
-		class_destroy(watchdog_class);
-		return err;
-	}
 
 	watchdog_deferred_registration();
 	return 0;
@@ -391,7 +381,6 @@ static int __init watchdog_init(void)
 static void __exit watchdog_exit(void)
 {
 	watchdog_dev_exit();
-	class_destroy(watchdog_class);
 	ida_destroy(&watchdog_ida);
 }
 

drivers/watchdog/watchdog_core.h

@@ -33,5 +33,5 @@
  */
 extern int watchdog_dev_register(struct watchdog_device *);
 extern int watchdog_dev_unregister(struct watchdog_device *);
-extern int __init watchdog_dev_init(void);
+extern struct class * __init watchdog_dev_init(void);
 extern void __exit watchdog_dev_exit(void);

drivers/watchdog/watchdog_dev.c

@@ -581,18 +581,35 @@ int watchdog_dev_unregister(struct watchdog_device *wdd)
 	return 0;
 }
 
+static struct class watchdog_class = {
+	.name =		"watchdog",
+	.owner =	THIS_MODULE,
+};
+
 /*
  *	watchdog_dev_init: init dev part of watchdog core
  *
  *	Allocate a range of chardev nodes to use for watchdog devices
  */
 
-int __init watchdog_dev_init(void)
+struct class * __init watchdog_dev_init(void)
 {
-	int err = alloc_chrdev_region(&watchdog_devt, 0, MAX_DOGS, "watchdog");
-	if (err < 0)
+	int err;
+
+	err = class_register(&watchdog_class);
+	if (err < 0) {
+		pr_err("couldn't register class\n");
+		return ERR_PTR(err);
+	}
+
+	err = alloc_chrdev_region(&watchdog_devt, 0, MAX_DOGS, "watchdog");
+	if (err < 0) {
 		pr_err("watchdog: unable to allocate char dev region\n");
-	return err;
+		class_unregister(&watchdog_class);
+		return ERR_PTR(err);
+	}
+
+	return &watchdog_class;
 }
 
 /*
@@ -604,4 +621,5 @@ int __init watchdog_dev_init(void)
 void __exit watchdog_dev_exit(void)
 {
 	unregister_chrdev_region(watchdog_devt, MAX_DOGS);
+	class_unregister(&watchdog_class);
 }