diff --git a/audio/4.0/IDevicesFactory.hal b/audio/4.0/IDevicesFactory.hal
index c552c6d..987fd68 100644
--- a/audio/4.0/IDevicesFactory.hal
+++ b/audio/4.0/IDevicesFactory.hal
@@ -19,41 +19,36 @@
 import android.hardware.audio.common@4.0;
 import IDevice;
 
+/** This factory allows a HAL implementation to be split in multiple independent
+ *  devices (called module in the pre-treble API).
+ *  Note that this division is arbitrary and implementation are free
+ *  to only have a Primary.
+ *  The framework will query the devices according to audio_policy_configuration.xml
+ *
+ *  Each device name is arbitrary, provided by the vendor's audio_policy_configuration.xml
+ *  and only used to identify a device in this factory.
+ *  The framework must not interpret the name, treating it as a vendor opaque data
+ *  with the following exceptions:
+ *  - the "primary" device must always be present and is the device used by the telephony framework.
+ *  - the "r_submix" device that must be present to support policyMixes (Eg: Android projected).
+ *    Note that this Device is included by default in a build derived from AOSP.
+ *
+ *  Note that on AOSP Oreo (including MR1) the "a2dp" module is not using this API
+ *  but is loaded directly from the system partition using the legacy API
+ *  due to limitations with the Bluetooth framework.
+ */
 interface IDevicesFactory {
-    /** Allows a HAL implementation to be split in multiple independent
-     *  devices (called module in the pre-treble API).
-     *  Note that this division is arbitrary and implementation are free
-     *  to only have a Primary.
-     *  The framework will query the devices according to audio_policy_configuration.xml
-     *
-     *  Each Device value is interchangeable with any other and the framework
-     *  does not differentiate between values with the following exceptions:
-     *  - the Primary device must always be present
-     *  - the R_SUBMIX that is used to forward audio of REMOTE_SUBMIX DEVICES
-     */
-    enum Device : int32_t {
-        PRIMARY,
-        A2DP,
-        USB,
-        R_SUBMIX,
-        STUB,
-        CODEC_OFFLOAD,
-        SECONDARY,
-        AUXILIARY,
-        /** Multi Stream Decoder */
-        MSD
-    };
 
     /**
      * Opens an audio device. To close the device, it is necessary to release
      * references to the returned device object.
      *
-     * @param device device type.
+     * @param device device name.
      * @return retval operation completion status. Returns INVALID_ARGUMENTS
      *         if there is no corresponding hardware module found,
      *         NOT_INITIALIZED if an error occured while opening the hardware
      *         module.
      * @return result the interface for the created device.
      */
-    openDevice(Device device) generates (Result retval, IDevice result);
+    openDevice(string device) generates (Result retval, IDevice result);
 };
diff --git a/audio/4.0/config/audio_policy_configuration.xsd b/audio/4.0/config/audio_policy_configuration.xsd
index 924fb47..e5b4449 100644
--- a/audio/4.0/config/audio_policy_configuration.xsd
+++ b/audio/4.0/config/audio_policy_configuration.xsd
@@ -66,35 +66,6 @@
     <xs:complexType name="globalConfiguration">
         <xs:attribute name="speaker_drc_enabled" type="xs:boolean" use="required"/>
     </xs:complexType>
-    <!-- Enum values of IDevicesFactory::Device
-         TODO: generate from hidl to avoid manual sync. -->
-    <xs:simpleType name="halName">
-        <xs:union>
-            <xs:simpleType>
-                <xs:restriction base="xs:string">
-                    <xs:enumeration value="primary"/>
-                    <xs:enumeration value="a2dp"/>
-                    <xs:enumeration value="usb"/>
-                    <xs:enumeration value="r_submix"/>
-                    <xs:enumeration value="codec_offload"/>
-                    <xs:enumeration value="stub"/>
-                </xs:restriction>
-            </xs:simpleType>
-            <xs:simpleType>
-                <xs:annotation>
-                    <xs:documentation xml:lang="en">
-                        Vendor eXtension names must be in the vx namespace.
-                        Vendor are encouraged to namespace their module names.
-                        Example for an hypothetical Google virtual reality HAL:
-                            <module name="vx_google_vr" halVersion="3.0"/>
-                    </xs:documentation>
-                </xs:annotation>
-                <xs:restriction base="xs:string">
-                    <xs:pattern value="vx_[_a-zA-Z0-9]+"/>
-                </xs:restriction>
-            </xs:simpleType>
-        </xs:union>
-    </xs:simpleType>
     <xs:complexType name="modules">
         <xs:annotation>
             <xs:documentation xml:lang="en">
@@ -133,7 +104,7 @@
                         <xs:element name="devicePorts" type="devicePorts" minOccurs="0"/>
                         <xs:element name="routes" type="routes" minOccurs="0"/>
                     </xs:sequence>
-                    <xs:attribute name="name" type="halName" use="required"/>
+                    <xs:attribute name="name" type="xsd:string" use="required"/>
                     <xs:attribute name="halVersion" type="halVersion" use="required"/>
                 </xs:complexType>
                 <xs:unique name="mixPortNameUniqueness">