1 files changed, 56 insertions, 17 deletions

diff --git a/drivers/s390/cio/ccwgroup.c b/drivers/s390/cio/ccwgroup.c
index b91c1719b075..22ce765d537e 100644
--- a/drivers/s390/cio/ccwgroup.c
+++ b/drivers/s390/cio/ccwgroup.c
@@ -315,16 +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);
@@ -392,27 +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
@@ -454,13 +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;
 }
 
@@ -469,9 +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);
 }
 
@@ -484,6 +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