USB: Push BKL on open down into the drivers

Straightforward push into the drivers to allow
auditing individual drivers separately

Signed-off-by: Oliver Neukum <oliver@neukum.org>
Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/misc/rio500.c b/drivers/usb/misc/rio500.c
index 17e4eec..47ce46b 100644
--- a/drivers/usb/misc/rio500.c
+++ b/drivers/usb/misc/rio500.c
@@ -77,7 +77,7 @@
 static int open_rio(struct inode *inode, struct file *file)
 {
 	struct rio_usb_data *rio = &rio_instance;
-
+	lock_kernel();
 	mutex_lock(&(rio->lock));
 
 	if (rio->isopen || !rio->present) {
@@ -91,6 +91,7 @@
 	mutex_unlock(&(rio->lock));
 
 	dev_info(&rio->rio_dev->dev, "Rio opened.\n");
+	unlock_kernel();
 
 	return 0;
 }