1 files changed, 29 insertions, 38 deletions

diff --git a/drivers/base/class.c b/drivers/base/class.c
index 05d9df90f621..2526c57d924e 100644
--- a/drivers/base/class.c
+++ b/drivers/base/class.c
@@ -183,6 +183,17 @@ int class_register(const struct class *cls)
 
 	pr_debug("device class '%s': registering\n", cls->name);
 
+	if (cls->ns_type && !cls->namespace) {
+		pr_err("%s: class '%s' does not have namespace\n",
+		       __func__, cls->name);
+		return -EINVAL;
+	}
+	if (!cls->ns_type && cls->namespace) {
+		pr_err("%s: class '%s' does not have ns_type\n",
+		       __func__, cls->name);
+		return -EINVAL;
+	}
+
 	cp = kzalloc(sizeof(*cp), GFP_KERNEL);
 	if (!cp)
 		return -ENOMEM;
@@ -193,10 +204,8 @@ int class_register(const struct class *cls)
 	lockdep_register_key(key);
 	__mutex_init(&cp->mutex, "subsys mutex", key);
 	error = kobject_set_name(&cp->subsys.kobj, "%s", cls->name);
-	if (error) {
-		kfree(cp);
-		return error;
-	}
+	if (error)
+		goto err_out;
 
 	cp->subsys.kobj.kset = class_kset;
 	cp->subsys.kobj.ktype = &class_ktype;
@@ -215,6 +224,7 @@ int class_register(const struct class *cls)
 	return 0;
 
 err_out:
+	lockdep_unregister_key(key);
 	kfree(cp);
 	return error;
 }
@@ -313,8 +323,12 @@ void class_dev_iter_init(struct class_dev_iter *iter, const struct class *class,
 	struct subsys_private *sp = class_to_subsys(class);
 	struct klist_node *start_knode = NULL;
 
-	if (!sp)
+	memset(iter, 0, sizeof(*iter));
+	if (!sp) {
+		pr_crit("%s: class %p was not registered yet\n",
+			__func__, class);
 		return;
+	}
 
 	if (start)
 		start_knode = &start->p->knode_class;
@@ -341,6 +355,9 @@ struct device *class_dev_iter_next(struct class_dev_iter *iter)
 	struct klist_node *knode;
 	struct device *dev;
 
+	if (!iter->sp)
+		return NULL;
+
 	while (1) {
 		knode = klist_next(&iter->ki);
 		if (!knode)
@@ -385,7 +402,7 @@ EXPORT_SYMBOL_GPL(class_dev_iter_exit);
  * code.  There's no locking restriction.
  */
 int class_for_each_device(const struct class *class, const struct device *start,
-			  void *data, int (*fn)(struct device *, void *))
+			  void *data, device_iter_t fn)
 {
 	struct subsys_private *sp = class_to_subsys(class);
 	struct class_dev_iter iter;
@@ -395,7 +412,7 @@ int class_for_each_device(const struct class *class, const struct device *start,
 	if (!class)
 		return -EINVAL;
 	if (!sp) {
-		WARN(1, "%s called for class '%s' before it was initialized",
+		WARN(1, "%s called for class '%s' before it was registered",
 		     __func__, class->name);
 		return -EINVAL;
 	}
@@ -434,8 +451,7 @@ EXPORT_SYMBOL_GPL(class_for_each_device);
  * code.  There's no locking restriction.
  */
 struct device *class_find_device(const struct class *class, const struct device *start,
-				 const void *data,
-				 int (*match)(struct device *, const void *))
+				 const void *data, device_match_t match)
 {
 	struct subsys_private *sp = class_to_subsys(class);
 	struct class_dev_iter iter;
@@ -444,7 +460,7 @@ struct device *class_find_device(const struct class *class, const struct device
 	if (!class)
 		return NULL;
 	if (!sp) {
-		WARN(1, "%s called for class '%s' before it was initialized",
+		WARN(1, "%s called for class '%s' before it was registered",
 		     __func__, class->name);
 		return NULL;
 	}
@@ -585,30 +601,10 @@ EXPORT_SYMBOL_GPL(class_compat_unregister);
  *			      a bus device
  * @cls: the compatibility class
  * @dev: the target bus device
- * @device_link: an optional device to which a "device" link should be created
  */
-int class_compat_create_link(struct class_compat *cls, struct device *dev,
-			     struct device *device_link)
+int class_compat_create_link(struct class_compat *cls, struct device *dev)
 {
-	int error;
-
-	error = sysfs_create_link(cls->kobj, &dev->kobj, dev_name(dev));
-	if (error)
-		return error;
-
-	/*
-	 * Optionally add a "device" link (typically to the parent), as a
-	 * class device would have one and we want to provide as much
-	 * backwards compatibility as possible.
-	 */
-	if (device_link) {
-		error = sysfs_create_link(&dev->kobj, &device_link->kobj,
-					  "device");
-		if (error)
-			sysfs_remove_link(cls->kobj, dev_name(dev));
-	}
-
-	return error;
+	return sysfs_create_link(cls->kobj, &dev->kobj, dev_name(dev));
 }
 EXPORT_SYMBOL_GPL(class_compat_create_link);
 
@@ -617,14 +613,9 @@ EXPORT_SYMBOL_GPL(class_compat_create_link);
  *			      a bus device
  * @cls: the compatibility class
  * @dev: the target bus device
- * @device_link: an optional device to which a "device" link was previously
- * 		 created
  */
-void class_compat_remove_link(struct class_compat *cls, struct device *dev,
-			      struct device *device_link)
+void class_compat_remove_link(struct class_compat *cls, struct device *dev)
 {
-	if (device_link)
-		sysfs_remove_link(&dev->kobj, "device");
 	sysfs_remove_link(cls->kobj, dev_name(dev));
 }
 EXPORT_SYMBOL_GPL(class_compat_remove_link);