mei: bus: unregister callbacks upon me client disable call

Stop and unregister receive and notification callbacks
from the disable function, to allow its later re-enablement.
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/misc/mei/bus.c

@@ -498,6 +498,25 @@ int mei_cldev_enable(struct mei_cl_device *cldev)
 }
 EXPORT_SYMBOL_GPL(mei_cldev_enable);
 
+/**
+ * mei_cldev_unregister_callbacks - internal wrapper for unregistering
+ *  callbacks.
+ *
+ * @cldev: client device
+ */
+static void mei_cldev_unregister_callbacks(struct mei_cl_device *cldev)
+{
+	if (cldev->rx_cb) {
+		cancel_work_sync(&cldev->rx_work);
+		cldev->rx_cb = NULL;
+	}
+
+	if (cldev->notif_cb) {
+		cancel_work_sync(&cldev->notif_work);
+		cldev->notif_cb = NULL;
+	}
+}
+
 /**
  * mei_cldev_disable - disable me client device
  *     disconnect form the me client
@@ -519,6 +538,8 @@ int mei_cldev_disable(struct mei_cl_device *cldev)
 
 	bus = cldev->bus;
 
+	mei_cldev_unregister_callbacks(cldev);
+
 	mutex_lock(&bus->device_lock);
 
 	if (!mei_cl_is_connected(cl)) {
@@ -700,14 +721,7 @@ static int mei_cl_device_remove(struct device *dev)
 	if (cldrv->remove)
 		ret = cldrv->remove(cldev);
 
-	if (cldev->rx_cb) {
-		cancel_work_sync(&cldev->rx_work);
-		cldev->rx_cb = NULL;
-	}
-	if (cldev->notif_cb) {
-		cancel_work_sync(&cldev->notif_work);
-		cldev->notif_cb = NULL;
-	}
+	mei_cldev_unregister_callbacks(cldev);
 
 	module_put(THIS_MODULE);
 	dev->driver = NULL;