1 files changed, 59 insertions, 19 deletions

diff --git a/drivers/s390/cio/ccwgroup.c b/drivers/s390/cio/ccwgroup.c
index 918e6fce2573..22ce765d537e 100644
--- a/drivers/s390/cio/ccwgroup.c
+++ b/drivers/s390/cio/ccwgroup.c
@@ -104,8 +104,9 @@ ccwgroup_ungroup_store(struct device *dev, struct device_attribute *attr, const
 	rc = device_schedule_callback(dev, ccwgroup_ungroup_callback);
 out:
 	if (rc) {
-		/* Release onoff "lock" when ungrouping failed. */
-		atomic_set(&gdev->onoff, 0);
+		if (rc != -EAGAIN)
+			/* Release onoff "lock" when ungrouping failed. */
+			atomic_set(&gdev->onoff, 0);
 		return rc;
 	}
 	return count;
@@ -314,16 +315,32 @@ error:
 }
 EXPORT_SYMBOL(ccwgroup_create_from_string);
 
-static int __init
-init_ccwgroup (void)
+static int ccwgroup_notifier(struct notifier_block *nb, unsigned long action,
+			     void *data);
+
+static struct notifier_block ccwgroup_nb = {
+	.notifier_call = ccwgroup_notifier
+};
+
+static int __init init_ccwgroup(void)
 {
-	return bus_register (&ccwgroup_bus_type);
+	int ret;
+
+	ret = bus_register(&ccwgroup_bus_type);
+	if (ret)
+		return ret;
+
+	ret = bus_register_notifier(&ccwgroup_bus_type, &ccwgroup_nb);
+	if (ret)
+		bus_unregister(&ccwgroup_bus_type);
+
+	return ret;
 }
 
-static void __exit
-cleanup_ccwgroup (void)
+static void __exit cleanup_ccwgroup(void)
 {
-	bus_unregister (&ccwgroup_bus_type);
+	bus_unregister_notifier(&ccwgroup_bus_type, &ccwgroup_nb);
+	bus_unregister(&ccwgroup_bus_type);
 }
 
 module_init(init_ccwgroup);
@@ -391,27 +408,28 @@ ccwgroup_online_store (struct device *dev, struct device_attribute *attr, const
 	unsigned long value;
 	int ret;
 
-	gdev = to_ccwgroupdev(dev);
 	if (!dev->driver)
-		return count;
+		return -ENODEV;
+
+	gdev = to_ccwgroupdev(dev);
+	gdrv = to_ccwgroupdrv(dev->driver);
 
-	gdrv = to_ccwgroupdrv (gdev->dev.driver);
 	if (!try_module_get(gdrv->owner))
 		return -EINVAL;
 
 	ret = strict_strtoul(buf, 0, &value);
 	if (ret)
 		goto out;
-	ret = count;
+
 	if (value == 1)
-		ccwgroup_set_online(gdev);
+		ret = ccwgroup_set_online(gdev);
 	else if (value == 0)
-		ccwgroup_set_offline(gdev);
+		ret = ccwgroup_set_offline(gdev);
 	else
 		ret = -EINVAL;
 out:
 	module_put(gdrv->owner);
-	return ret;
+	return (ret == 0) ? count : ret;
 }
 
 static ssize_t
@@ -453,13 +471,18 @@ ccwgroup_remove (struct device *dev)
 	struct ccwgroup_device *gdev;
 	struct ccwgroup_driver *gdrv;
 
+	device_remove_file(dev, &dev_attr_online);
+	device_remove_file(dev, &dev_attr_ungroup);
+
+	if (!dev->driver)
+		return 0;
+
 	gdev = to_ccwgroupdev(dev);
 	gdrv = to_ccwgroupdrv(dev->driver);
 
-	device_remove_file(dev, &dev_attr_online);
-
-	if (gdrv && gdrv->remove)
+	if (gdrv->remove)
 		gdrv->remove(gdev);
+
 	return 0;
 }
 
@@ -468,9 +491,13 @@ static void ccwgroup_shutdown(struct device *dev)
 	struct ccwgroup_device *gdev;
 	struct ccwgroup_driver *gdrv;
 
+	if (!dev->driver)
+		return;
+
 	gdev = to_ccwgroupdev(dev);
 	gdrv = to_ccwgroupdrv(dev->driver);
-	if (gdrv && gdrv->shutdown)
+
+	if (gdrv->shutdown)
 		gdrv->shutdown(gdev);
 }
 
@@ -483,6 +510,19 @@ static struct bus_type ccwgroup_bus_type = {
 	.shutdown = ccwgroup_shutdown,
 };
 
+
+static int ccwgroup_notifier(struct notifier_block *nb, unsigned long action,
+			     void *data)
+{
+	struct device *dev = data;
+
+	if (action == BUS_NOTIFY_UNBIND_DRIVER)
+		device_schedule_callback(dev, ccwgroup_ungroup_callback);
+
+	return NOTIFY_OK;
+}
+
+
 /**
  * ccwgroup_driver_register() - register a ccw group driver
  * @cdriver: driver to be registered