doc: Update Features property description

diff --git a/doc/modem-api.txt b/doc/modem-api.txt
index b82bd31..dfb9926 100644 (file)
--- a/doc/modem-api.txt
+++ b/doc/modem-api.txt
@@ -89,6 +89,14 @@ Properties   boolean Powered [readwrite]
                        List of currently enabled features. It uses simple
                        string abbreviations like "sms", "sim" etc.
 
+                       Currently available features are:
+                               "net", "rat", "cbs", "sms", "sim", "stk",
+                               "ussd", "gprs", "tty", "gps".
+
+                       Please note that this is a convenience property,
+                       equivalent results can be obtained by reading the
+                       Interfaces property directly.
+
                array{string} Interfaces [readonly]
 
                        Set of interfaces currently supported by the mode