Driver core updates (needed for serio)

diff -Nru a/drivers/base/bus.c b/drivers/base/bus.c
@@ -415,7 +415,7 @@
 static void device_remove_attrs(struct bus_type * bus, struct device * dev)
 {
 	int i;
-	
+
 	if (bus->dev_attrs) {
 		for (i = 0; attr_name(bus->dev_attrs[i]); i++)
 			device_remove_file(dev,&bus->dev_attrs[i]);

@@ -471,6 +471,37 @@
 	}
 }
 
+static int driver_add_attrs(struct bus_type * bus, struct device_driver * drv)
+{
+	int error = 0;
+	int i;
+
+	if (bus->drv_attrs) {
+		for (i = 0; attr_name(bus->drv_attrs[i]); i++) {
+			error = driver_create_file(drv, &bus->drv_attrs[i]);
+			if (error)
+				goto Err;
+		}
+	}
+ Done:
+	return error;
+ Err:
+	while (--i >= 0)
+		driver_remove_file(drv, &bus->drv_attrs[i]);
+	goto Done;
+}
+
+
+static void driver_remove_attrs(struct bus_type * bus, struct device_driver * drv)
+{
+	int i;
+
+	if (bus->drv_attrs) {
+		for (i = 0; attr_name(bus->drv_attrs[i]); i++)
+			driver_remove_file(drv, &bus->drv_attrs[i]);
+	}
+}
+
 
 /**
  *	bus_add_driver - Add a driver to the bus.

@@ -499,6 +530,7 @@
 		driver_attach(drv);
 		up_write(&bus->subsys.rwsem);
 
+		driver_add_attrs(bus, drv);
 	}
 	return error;
 }

@@ -516,6 +548,7 @@
 void bus_remove_driver(struct device_driver * drv)
 {
 	if (drv->bus) {
+		driver_remove_attrs(drv->bus, drv);
 		down_write(&drv->bus->subsys.rwsem);
 		pr_debug("bus %s: remove driver %s\n", drv->bus->name, drv->name);
 		driver_detach(drv);

@@ -610,7 +643,7 @@
 static void bus_remove_attrs(struct bus_type * bus)
 {
 	int i;
-	
+
 	if (bus->bus_attrs) {
 		for (i = 0; attr_name(bus->bus_attrs[i]); i++)
 			bus_remove_file(bus,&bus->bus_attrs[i]);

diff -Nru a/include/linux/device.h b/include/linux/device.h
@@ -56,6 +56,7 @@
 
 	struct bus_attribute	* bus_attrs;
 	struct device_attribute	* dev_attrs;
+	struct driver_attribute	* drv_attrs;
 
 	int		(*match)(struct device * dev, struct device_driver * drv);
 	struct device * (*add)	(struct device * parent, char * bus_id);

diff -Nru a/drivers/base/bus.c b/drivers/base/bus.c
@@ -607,6 +607,8 @@
  *
  *	Call kset_find_obj() to iterate over list of buses to
  *	find a bus by name. Return bus if found.
+ *
+ *	Note that kset_find_obj increments bus' reference count.
  */
 
 struct bus_type * find_bus(char * name)

diff -Nru a/drivers/base/core.c b/drivers/base/core.c
@@ -378,6 +378,16 @@
 	return error;
 }
 
+/**
+ *	device_find - locate device on a bus by name.
+ *	@name:	name of the device.
+ *	@bus:	bus to scan for the device.
+ *
+ *	Call kset_find_obj() to iterate over list of devices on
+ *	a bus to find device by name. Return device if found.
+ *
+ *	Note that kset_find_obj increments device's reference count.
+ */
 struct device *device_find(const char *name, struct bus_type *bus)
 {
 	struct kobject *k = kset_find_obj(&bus->devices, name);

diff -Nru a/drivers/pci/hotplug/rpaphp_vio.c b/drivers/pci/hotplug/rpaphp_vio.c
@@ -86,7 +86,14 @@
 	}
 	slot->dev_type = VIO_DEV;
 	slot->dev.vio_dev = vio_find_node(dn);
-	if (!slot->dev.vio_dev)
+	if (slot->dev.vio_dev) {
+		/*
+		 * rpaphp is the only owner of vio devices and
+		 * does not need extra reference taken by
+		 * vio_find_node
+		 */
+		put_device(&slot->dev.vio_dev->dev);
+	} else
 		slot->dev.vio_dev = vio_register_device_node(dn);
 	if (slot->dev.vio_dev)
 		slot->state = CONFIGURED;

diff -Nru a/lib/kobject.c b/lib/kobject.c
@@ -537,7 +537,8 @@
  *	@name:	object's name.
  *
  *	Lock kset via @kset->subsys, and iterate over @kset->list,
- *	looking for a matching kobject. Return object if found.
+ *	looking for a matching kobject. If matching object is found
+ *	take a reference and return the object.
  */
 
 struct kobject * kset_find_obj(struct kset * kset, const char * name)

@@ -548,8 +549,8 @@
 	down_read(&kset->subsys->rwsem);
 	list_for_each(entry,&kset->list) {
 		struct kobject * k = to_kobj(entry);
-		if (kobject_name(k) && (!strcmp(kobject_name(k),name))) {
-			ret = k;
+		if (kobject_name(k) && !strcmp(kobject_name(k),name)) {
+			ret = kobject_get(k);
 			break;
 		}
 	}

diff -Nru a/drivers/base/driver.c b/drivers/base/driver.c
@@ -111,10 +111,29 @@
 	up(&drv->unload_sem);
 }
 
+/**
+ *	driver_find - locate driver on a bus by its name.
+ *	@name:	name of the driver.
+ *	@bus:	bus to scan for the driver.
+ *
+ *	Call kset_find_obj() to iterate over list of drivers on
+ *	a bus to find driver by name. Return driver if found.
+ *
+ *	Note that kset_find_obj increments driver's reference count.
+ */
+struct device_driver *driver_find(const char *name, struct bus_type *bus)
+{
+	struct kobject *k = kset_find_obj(&bus->drivers, name);
+	if (k)
+		return to_drv(k);
+	return NULL;
+}
+
 EXPORT_SYMBOL(driver_register);
 EXPORT_SYMBOL(driver_unregister);
 EXPORT_SYMBOL(get_driver);
 EXPORT_SYMBOL(put_driver);
+EXPORT_SYMBOL(driver_find);
 
 EXPORT_SYMBOL(driver_create_file);
 EXPORT_SYMBOL(driver_remove_file);

diff -Nru a/include/linux/device.h b/include/linux/device.h
@@ -120,6 +120,7 @@
 
 extern struct device_driver * get_driver(struct device_driver * drv);
 extern void put_driver(struct device_driver * drv);
+extern struct device_driver *driver_find(const char *name, struct bus_type *bus);
 
 
 /* driverfs interface for exporting driver attributes */