Add details about Interface property

diff --git a/doc/device-api.txt b/doc/device-api.txt
index 45c7215..7d1b86f 100644 (file)
--- a/doc/device-api.txt
+++ b/doc/device-api.txt
@@ -54,6 +54,13 @@ Properties   string Name [readonly]
 
                        The device type (for example "ethernet", "wifi" etc.)
 
+               string Interface [readonly]
+
+                       The device interface (for example "eth0" etc.)
+
+                       This value is for pure informational purposes. It
+                       is not guaranteed that it is always present.
+
                string Policy [readwrite]
 
                        Setting of the device power policy. Possible values