Class: add support for class interfaces for devices

When moving class_device usage over to device, we need to handle
class_interfaces properly with devices.  This patch adds that support.
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

drivers/base/class.c

@@ -842,6 +842,7 @@ int class_interface_register(struct class_interface *class_intf)
 {
 	struct class *parent;
 	struct class_device *class_dev;
+	struct device *dev;
 
 	if (!class_intf || !class_intf->class)
 		return -ENODEV;
@@ -856,6 +857,10 @@ int class_interface_register(struct class_interface *class_intf)
 		list_for_each_entry(class_dev, &parent->children, node)
 			class_intf->add(class_dev, class_intf);
 	}
+	if (class_intf->add_dev) {
+		list_for_each_entry(dev, &parent->devices, node)
+			class_intf->add_dev(dev, class_intf);
+	}
 	up(&parent->sem);
 
 	return 0;
@@ -865,6 +870,7 @@ void class_interface_unregister(struct class_interface *class_intf)
 {
 	struct class * parent = class_intf->class;
 	struct class_device *class_dev;
+	struct device *dev;
 
 	if (!parent)
 		return;
@@ -875,6 +881,10 @@ void class_interface_unregister(struct class_interface *class_intf)
 		list_for_each_entry(class_dev, &parent->children, node)
 			class_intf->remove(class_dev, class_intf);
 	}
+	if (class_intf->remove_dev) {
+		list_for_each_entry(dev, &parent->devices, node)
+			class_intf->remove_dev(dev, class_intf);
+	}
 	up(&parent->sem);
 
 	class_put(parent);

drivers/base/core.c

@@ -372,6 +372,7 @@ int device_add(struct device *dev)
 {
 	struct device *parent = NULL;
 	char *class_name = NULL;
+	struct class_interface *class_intf;
 	int error = -EINVAL;
 
 	dev = get_device(dev);
@@ -451,9 +452,14 @@ int device_add(struct device *dev)
 		klist_add_tail(&dev->knode_parent, &parent->klist_children);
 
 	if (dev->class) {
-		/* tie the class to the device */
 		down(&dev->class->sem);
+		/* tie the class to the device */
 		list_add_tail(&dev->node, &dev->class->devices);
+
+		/* notify any interfaces that the device is here */
+		list_for_each_entry(class_intf, &dev->class->interfaces, node)
+			if (class_intf->add_dev)
+				class_intf->add_dev(dev, class_intf);
 		up(&dev->class->sem);
 	}
 
@@ -548,6 +554,7 @@ void device_del(struct device * dev)
 {
 	struct device * parent = dev->parent;
 	char *class_name = NULL;
+	struct class_interface *class_intf;
 
 	if (parent)
 		klist_del(&dev->knode_parent);
@@ -563,6 +570,11 @@ void device_del(struct device * dev)
 		}
 		kfree(class_name);
 		down(&dev->class->sem);
+		/* notify any interfaces that the device is now gone */
+		list_for_each_entry(class_intf, &dev->class->interfaces, node)
+			if (class_intf->remove_dev)
+				class_intf->remove_dev(dev, class_intf);
+		/* remove the device from the class list */
 		list_del_init(&dev->node);
 		up(&dev->class->sem);
 	}

include/linux/device.h

@@ -278,6 +278,8 @@ struct class_interface {
 
 	int (*add)	(struct class_device *, struct class_interface *);
 	void (*remove)	(struct class_device *, struct class_interface *);
+	int (*add_dev)		(struct device *, struct class_interface *);
+	void (*remove_dev)	(struct device *, struct class_interface *);
 };
 
 extern int class_interface_register(struct class_interface *);