diff --git a/gst/gstdeviceprovider.c b/gst/gstdeviceprovider.c
index 8ad737cd41..995c2ff8ad 100644
--- a/gst/gstdeviceprovider.c
+++ b/gst/gstdeviceprovider.c
@@ -543,6 +543,9 @@ gst_device_provider_device_add (GstDeviceProvider * provider,
 {
   GstMessage *message;
 
+  g_return_if_fail (GST_IS_DEVICE_PROVIDER (provider));
+  g_return_if_fail (GST_IS_DEVICE (device));
+
   if (!gst_object_set_parent (GST_OBJECT (device), GST_OBJECT (provider))) {
     GST_WARNING_OBJECT (provider, "Could not parent device %p to provider,"
         " it already has a parent", device);
@@ -579,6 +582,9 @@ gst_device_provider_device_remove (GstDeviceProvider * provider,
   GstMessage *message;
   GList *item;
 
+  g_return_if_fail (GST_IS_DEVICE_PROVIDER (provider));
+  g_return_if_fail (GST_IS_DEVICE (device));
+
   GST_OBJECT_LOCK (provider);
   item = g_list_find (provider->devices, device);
   if (item) {
diff --git a/gst/gstdeviceprovider.h b/gst/gstdeviceprovider.h
index 6370afc657..3982f3b89c 100644
--- a/gst/gstdeviceprovider.h
+++ b/gst/gstdeviceprovider.h
@@ -111,31 +111,31 @@ gboolean    gst_device_provider_can_monitor    (GstDeviceProvider * provider);
 GstBus *    gst_device_provider_get_bus        (GstDeviceProvider * provider);
 
 void        gst_device_provider_device_add     (GstDeviceProvider * provider,
-                                               GstDevice * device);
+                                                GstDevice * device);
 void        gst_device_provider_device_remove  (GstDeviceProvider * provider,
                                                GstDevice * device);
 
 
 /* device provider class meta data */
-void        gst_device_provider_class_set_metadata          (GstDeviceProviderClass *klass,
+void        gst_device_provider_class_set_metadata         (GstDeviceProviderClass *klass,
                                                             const gchar     *longname,
                                                             const gchar     *classification,
                                                             const gchar     *description,
                                                             const gchar     *author);
-void        gst_device_provider_class_set_static_metadata   (GstDeviceProviderClass *klass,
+void        gst_device_provider_class_set_static_metadata  (GstDeviceProviderClass *klass,
                                                             const gchar     *longname,
                                                             const gchar     *classification,
                                                             const gchar     *description,
                                                             const gchar     *author);
-void        gst_device_provider_class_add_metadata          (GstDeviceProviderClass * klass,
+void        gst_device_provider_class_add_metadata         (GstDeviceProviderClass * klass,
                                                             const gchar * key, const gchar * value);
-void        gst_device_provider_class_add_static_metadata   (GstDeviceProviderClass * klass,
+void        gst_device_provider_class_add_static_metadata  (GstDeviceProviderClass * klass,
                                                             const gchar * key, const gchar * value);
-const gchar * gst_device_provider_class_get_metadata        (GstDeviceProviderClass * klass,
-                                                              const gchar * key);
+const gchar * gst_device_provider_class_get_metadata       (GstDeviceProviderClass * klass,
+                                                            const gchar * key);
 
 /* factory management */
-GstDeviceProviderFactory * gst_device_provider_get_factory   (GstDeviceProvider * provider);
+GstDeviceProviderFactory * gst_device_provider_get_factory (GstDeviceProvider * provider);
 
 G_END_DECLS