diff --git a/core/api/current.txt b/core/api/current.txt
index 69422212fb841..5145f03b9f091 100644
--- a/core/api/current.txt
+++ b/core/api/current.txt
@@ -25710,6 +25710,7 @@ package android.media.midi {
 
   public final class MidiDeviceInfo implements android.os.Parcelable {
     method public int describeContents();
+    method public int getDefaultProtocol();
     method public int getId();
     method public int getInputPortCount();
     method public int getOutputPortCount();
@@ -25726,6 +25727,14 @@ package android.media.midi {
     field public static final String PROPERTY_SERIAL_NUMBER = "serial_number";
     field public static final String PROPERTY_USB_DEVICE = "usb_device";
     field public static final String PROPERTY_VERSION = "version";
+    field public static final int PROTOCOL_UMP_MIDI_1_0_UP_TO_128_BITS = 3; // 0x3
+    field public static final int PROTOCOL_UMP_MIDI_1_0_UP_TO_128_BITS_AND_JRTS = 4; // 0x4
+    field public static final int PROTOCOL_UMP_MIDI_1_0_UP_TO_64_BITS = 1; // 0x1
+    field public static final int PROTOCOL_UMP_MIDI_1_0_UP_TO_64_BITS_AND_JRTS = 2; // 0x2
+    field public static final int PROTOCOL_UMP_MIDI_2_0 = 17; // 0x11
+    field public static final int PROTOCOL_UMP_MIDI_2_0_AND_JRTS = 18; // 0x12
+    field public static final int PROTOCOL_UMP_USE_MIDI_CI = 0; // 0x0
+    field public static final int PROTOCOL_UNKNOWN = -1; // 0xffffffff
     field public static final int TYPE_BLUETOOTH = 3; // 0x3
     field public static final int TYPE_USB = 1; // 0x1
     field public static final int TYPE_VIRTUAL = 2; // 0x2
@@ -25767,10 +25776,14 @@ package android.media.midi {
 
   public final class MidiManager {
     method public android.media.midi.MidiDeviceInfo[] getDevices();
+    method @NonNull public java.util.Collection<android.media.midi.MidiDeviceInfo> getDevicesForTransport(int);
     method public void openBluetoothDevice(android.bluetooth.BluetoothDevice, android.media.midi.MidiManager.OnDeviceOpenedListener, android.os.Handler);
     method public void openDevice(android.media.midi.MidiDeviceInfo, android.media.midi.MidiManager.OnDeviceOpenedListener, android.os.Handler);
     method public void registerDeviceCallback(android.media.midi.MidiManager.DeviceCallback, android.os.Handler);
+    method public void registerDeviceCallbackForTransport(@NonNull android.media.midi.MidiManager.DeviceCallback, @Nullable android.os.Handler, int);
     method public void unregisterDeviceCallback(android.media.midi.MidiManager.DeviceCallback);
+    field public static final int TRANSPORT_MIDI_BYTE_STREAM = 1; // 0x1
+    field public static final int TRANSPORT_UNIVERSAL_MIDI_PACKETS = 2; // 0x2
   }
 
   public static class MidiManager.DeviceCallback {
diff --git a/media/java/android/media/midi/IMidiManager.aidl b/media/java/android/media/midi/IMidiManager.aidl
index d3c8e0adb3ced..b03f785046358 100644
--- a/media/java/android/media/midi/IMidiManager.aidl
+++ b/media/java/android/media/midi/IMidiManager.aidl
@@ -31,6 +31,8 @@ interface IMidiManager
 {
     MidiDeviceInfo[] getDevices();
 
+    MidiDeviceInfo[] getDevicesForTransport(int transport);
+
     // for device creation & removal notifications
     void registerListener(IBinder clientToken, in IMidiDeviceListener listener);
     void unregisterListener(IBinder clientToken, in IMidiDeviceListener listener);
@@ -43,7 +45,7 @@ interface IMidiManager
     // for registering built-in MIDI devices
     MidiDeviceInfo registerDeviceServer(in IMidiDeviceServer server, int numInputPorts,
             int numOutputPorts, in String[] inputPortNames, in String[] outputPortNames,
-            in Bundle properties, int type);
+            in Bundle properties, int type, int defaultProtocol);
 
     // for unregistering built-in MIDI devices
     void unregisterDeviceServer(in IMidiDeviceServer server);
diff --git a/media/java/android/media/midi/MidiDeviceInfo.java b/media/java/android/media/midi/MidiDeviceInfo.java
index dd3b6dbd6a399..b888fb00df9bb 100644
--- a/media/java/android/media/midi/MidiDeviceInfo.java
+++ b/media/java/android/media/midi/MidiDeviceInfo.java
@@ -16,11 +16,15 @@
 
 package android.media.midi;
 
+import android.annotation.IntDef;
 import android.os.Bundle;
 import android.os.Parcel;
 import android.os.Parcelable;
 import android.util.Log;
 
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+
 /**
  * This class contains information to describe a MIDI device.
  * For now we only have information that can be retrieved easily for USB devices,
@@ -53,6 +57,110 @@ public final class MidiDeviceInfo implements Parcelable {
      */
     public static final int TYPE_BLUETOOTH = 3;
 
+    /**
+     * Constant representing a default protocol with Universal MIDI Packets (UMP).
+     * UMP is defined in "Universal MIDI Packet (UMP) Format and MIDI 2.0 Protocol" spec.
+     * All UMP data should be a multiple of 4 bytes.
+     * Use UMP to negotiate with the device with MIDI-CI.
+     * MIDI-CI is defined in "MIDI Capability Inquiry (MIDI-CI)" spec.
+     * Call {@link MidiManager#getDevicesForTransport} with parameter
+     * {@link MidiManager#TRANSPORT_UNIVERSAL_MIDI_PACKETS} to get devices with this transport.
+     * @see MidiDeviceInfo#getDefaultProtocol
+     */
+    public static final int PROTOCOL_UMP_USE_MIDI_CI = 0;
+
+    /**
+     * Constant representing a default protocol with Universal MIDI Packets (UMP).
+     * UMP is defined in "Universal MIDI Packet (UMP) Format and MIDI 2.0 Protocol" spec.
+     * All UMP data should be a multiple of 4 bytes.
+     * Use MIDI 1.0 through UMP with packet sizes up to 64 bits.
+     * Call {@link MidiManager#getDevicesForTransport} with parameter
+     * {@link MidiManager#TRANSPORT_UNIVERSAL_MIDI_PACKETS} to get devices with this transport.
+     * @see MidiDeviceInfo#getDefaultProtocol
+     */
+    public static final int PROTOCOL_UMP_MIDI_1_0_UP_TO_64_BITS = 1;
+
+    /**
+     * Constant representing a default protocol with Universal MIDI Packets (UMP).
+     * UMP is defined in "Universal MIDI Packet (UMP) Format and MIDI 2.0 Protocol" spec.
+     * All UMP data should be a multiple of 4 bytes.
+     * Use MIDI 1.0 through UMP with packet sizes up to 64 bits and jitter reduction timestamps.
+     * Call {@link MidiManager#getDevicesForTransport} with parameter
+     * {@link MidiManager#TRANSPORT_UNIVERSAL_MIDI_PACKETS} to get devices with this transport.
+     * @see MidiDeviceInfo#getDefaultProtocol
+     */
+    public static final int PROTOCOL_UMP_MIDI_1_0_UP_TO_64_BITS_AND_JRTS = 2;
+
+    /**
+     * Constant representing a default protocol with Universal MIDI Packets (UMP).
+     * UMP is defined in "Universal MIDI Packet (UMP) Format and MIDI 2.0 Protocol" spec.
+     * All UMP data should be a multiple of 4 bytes.
+     * Use MIDI 1.0 through UMP with packet sizes up to 128 bits.
+     * Call {@link MidiManager#getDevicesForTransport} with parameter
+     * {@link MidiManager#TRANSPORT_UNIVERSAL_MIDI_PACKETS} to get devices with this transport.
+     * @see MidiDeviceInfo#getDefaultProtocol
+     */
+    public static final int PROTOCOL_UMP_MIDI_1_0_UP_TO_128_BITS = 3;
+
+    /**
+     * Constant representing a default protocol with Universal MIDI Packets (UMP).
+     * UMP is defined in "Universal MIDI Packet (UMP) Format and MIDI 2.0 Protocol" spec.
+     * All UMP data should be a multiple of 4 bytes.
+     * Use MIDI 1.0 through UMP with packet sizes up to 128 bits and jitter reduction timestamps.
+     * Call {@link MidiManager#getDevicesForTransport} with parameter
+     * {@link MidiManager#TRANSPORT_UNIVERSAL_MIDI_PACKETS} to get devices with this transport.
+     * @see MidiDeviceInfo#getDefaultProtocol
+     */
+    public static final int PROTOCOL_UMP_MIDI_1_0_UP_TO_128_BITS_AND_JRTS = 4;
+
+    /**
+     * Constant representing a default protocol with Universal MIDI Packets (UMP).
+     * UMP is defined in "Universal MIDI Packet (UMP) Format and MIDI 2.0 Protocol" spec.
+     * All UMP data should be a multiple of 4 bytes.
+     * Use MIDI 2.0 through UMP.
+     * Call {@link MidiManager#getDevicesForTransport} with parameter
+     * {@link MidiManager#TRANSPORT_UNIVERSAL_MIDI_PACKETS} to get devices with this transport.
+     * @see MidiDeviceInfo#getDefaultProtocol
+     */
+    public static final int PROTOCOL_UMP_MIDI_2_0 = 17;
+
+     /**
+     * Constant representing a default protocol with Universal MIDI Packets (UMP).
+     * UMP is defined in "Universal MIDI Packet (UMP) Format and MIDI 2.0 Protocol" spec.
+     * All UMP data should be a multiple of 4 bytes.
+     * Use MIDI 2.0 through UMP and jitter reduction timestamps.
+     * Call {@link MidiManager#getDevicesForTransport} with parameter
+     * {@link MidiManager#TRANSPORT_UNIVERSAL_MIDI_PACKETS} to get devices with this transport.
+     * @see MidiDeviceInfo#getDefaultProtocol
+     */
+    public static final int PROTOCOL_UMP_MIDI_2_0_AND_JRTS = 18;
+
+    /**
+     * Constant representing a device with an unknown default protocol.
+     * If Universal MIDI Packets (UMP) are needed, use MIDI-CI through MIDI 1.0.
+     * UMP is defined in "Universal MIDI Packet (UMP) Format and MIDI 2.0 Protocol" spec.
+     * MIDI-CI is defined in "MIDI Capability Inquiry (MIDI-CI)" spec.
+     * @see MidiDeviceInfo#getDefaultProtocol
+     */
+    public static final int PROTOCOL_UNKNOWN = -1;
+
+    /**
+     * @see MidiDeviceInfo#getDefaultProtocol
+     * @hide
+     */
+    @IntDef(prefix = { "PROTOCOL_" }, value = {
+            PROTOCOL_UMP_USE_MIDI_CI,
+            PROTOCOL_UMP_MIDI_1_0_UP_TO_64_BITS,
+            PROTOCOL_UMP_MIDI_1_0_UP_TO_64_BITS_AND_JRTS,
+            PROTOCOL_UMP_MIDI_1_0_UP_TO_128_BITS,
+            PROTOCOL_UMP_MIDI_1_0_UP_TO_128_BITS_AND_JRTS,
+            PROTOCOL_UMP_MIDI_2_0,
+            PROTOCOL_UMP_MIDI_2_0_AND_JRTS,
+            PROTOCOL_UNKNOWN
+    })
+    @Retention(RetentionPolicy.SOURCE)
+    public @interface DefaultProtocol {}
+
     /**
      * Bundle key for the device's user visible name property.
      * The value for this property is of type {@link java.lang.String}.
@@ -196,6 +304,7 @@ public final class MidiDeviceInfo implements Parcelable {
     private final String[] mOutputPortNames;
     private final Bundle mProperties;
     private final boolean mIsPrivate;
+    private final int mDefaultProtocol;
 
     /**
      * MidiDeviceInfo should only be instantiated by MidiService implementation
@@ -203,7 +312,7 @@ public final class MidiDeviceInfo implements Parcelable {
      */
     public MidiDeviceInfo(int type, int id, int numInputPorts, int numOutputPorts,
             String[] inputPortNames, String[] outputPortNames, Bundle properties,
-            boolean isPrivate) {
+            boolean isPrivate, int defaultProtocol) {
         // Check num ports for out-of-range values. Typical values will be
         // between zero and three. More than 16 would be very unlikely
         // because the port index field in the USB packet is only 4 bits.
@@ -234,6 +343,7 @@ public final class MidiDeviceInfo implements Parcelable {
         }
         mProperties = properties;
         mIsPrivate = isPrivate;
+        mDefaultProtocol = defaultProtocol;
     }
 
     /**
@@ -312,6 +422,18 @@ public final class MidiDeviceInfo implements Parcelable {
         return mIsPrivate;
     }
 
+    /**
+     * Returns the default protocol. For most devices, this will be {@link #PROTOCOL_UNKNOWN}.
+     * Returning {@link #PROTOCOL_UNKNOWN} is not an error; the device just doesn't support
+     * Universal MIDI Packets by default.
+     *
+     * @return the device's default protocol.
+     */
+    @DefaultProtocol
+    public int getDefaultProtocol() {
+        return mDefaultProtocol;
+    }
+
     @Override
     public boolean equals(Object o) {
         if (o instanceof MidiDeviceInfo) {
@@ -331,11 +453,12 @@ public final class MidiDeviceInfo implements Parcelable {
         // This is a hack to force the mProperties Bundle to unparcel so we can
         // print all the names and values.
         mProperties.getString(PROPERTY_NAME);
-        return ("MidiDeviceInfo[mType=" + mType +
-                ",mInputPortCount=" + mInputPortCount +
-                ",mOutputPortCount=" + mOutputPortCount +
-                ",mProperties=" + mProperties +
-                ",mIsPrivate=" + mIsPrivate);
+        return ("MidiDeviceInfo[mType=" + mType
+                + ",mInputPortCount=" + mInputPortCount
+                + ",mOutputPortCount=" + mOutputPortCount
+                + ",mProperties=" + mProperties
+                + ",mIsPrivate=" + mIsPrivate
+                + ",mDefaultProtocol=" + mDefaultProtocol);
     }
 
     public static final @android.annotation.NonNull Parcelable.Creator<MidiDeviceInfo> CREATOR =
@@ -349,10 +472,12 @@ public final class MidiDeviceInfo implements Parcelable {
             String[] inputPortNames = in.createStringArray();
             String[] outputPortNames = in.createStringArray();
             boolean isPrivate = (in.readInt() == 1);
+            int defaultProtocol = in.readInt();
             Bundle basicPropertiesIgnored = in.readBundle();
             Bundle properties = in.readBundle();
             return new MidiDeviceInfo(type, id, inputPortCount, outputPortCount,
-                    inputPortNames, outputPortNames, properties, isPrivate);
+                    inputPortNames, outputPortNames, properties, isPrivate,
+                    defaultProtocol);
         }
 
         public MidiDeviceInfo[] newArray(int size) {
@@ -390,6 +515,7 @@ public final class MidiDeviceInfo implements Parcelable {
         parcel.writeStringArray(mInputPortNames);
         parcel.writeStringArray(mOutputPortNames);
         parcel.writeInt(mIsPrivate ? 1 : 0);
+        parcel.writeInt(mDefaultProtocol);
         // "Basic" properties only contain properties of primitive types
         // and thus can be read back by native code. "Extra" properties is
         // a superset that contains all properties.
diff --git a/media/java/android/media/midi/MidiManager.java b/media/java/android/media/midi/MidiManager.java
index dee94c681e87a..a049a8891f48f 100644
--- a/media/java/android/media/midi/MidiManager.java
+++ b/media/java/android/media/midi/MidiManager.java
@@ -16,18 +16,25 @@
 
 package android.media.midi;
 
+import android.annotation.IntDef;
+import android.annotation.NonNull;
+import android.annotation.Nullable;
 import android.annotation.RequiresFeature;
 import android.annotation.SystemService;
 import android.bluetooth.BluetoothDevice;
 import android.content.Context;
 import android.content.pm.PackageManager;
 import android.os.Binder;
-import android.os.IBinder;
 import android.os.Bundle;
 import android.os.Handler;
+import android.os.IBinder;
 import android.os.RemoteException;
 import android.util.Log;
 
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.util.ArrayList;
+import java.util.Collection;
 import java.util.concurrent.ConcurrentHashMap;
 
 /**
@@ -38,6 +45,39 @@ import java.util.concurrent.ConcurrentHashMap;
 public final class MidiManager {
     private static final String TAG = "MidiManager";
 
+    /**
+     * Constant representing MIDI devices.
+     * These devices do NOT support Universal MIDI Packets by default.
+     * These support the original MIDI 1.0 byte stream.
+     * When communicating to a USB device, a raw byte stream will be padded for USB.
+     * Likewise, for a Bluetooth device, the raw bytes will be converted for Bluetooth.
+     * For virtual devices, the byte stream will be passed directly.
+     * If Universal MIDI Packets are needed, please use MIDI-CI.
+     * @see MidiManager#getDevicesForTransport
+     */
+    public static final int TRANSPORT_MIDI_BYTE_STREAM = 1;
+
+    /**
+     * Constant representing Universal MIDI devices.
+     * These devices do support Universal MIDI Packets (UMP) by default.
+     * When sending data to these devices, please send UMP.
+     * Packets should always be a multiple of 4 bytes.
+     * UMP is defined in the USB MIDI 2.0 spec. Please read the standard for more info.
+     * @see MidiManager#getDevicesForTransport
+     */
+    public static final int TRANSPORT_UNIVERSAL_MIDI_PACKETS = 2;
+
+    /**
+     * @see MidiManager#getDevicesForTransport
+     * @hide
+     */
+    @IntDef(prefix = { "TRANSPORT_" }, value = {
+            TRANSPORT_MIDI_BYTE_STREAM,
+            TRANSPORT_UNIVERSAL_MIDI_PACKETS
+    })
+    @Retention(RetentionPolicy.SOURCE)
+    public @interface Transport {}
+
     /**
      * Intent for starting BluetoothMidiService
      * @hide
@@ -68,37 +108,43 @@ public final class MidiManager {
     private class DeviceListener extends IMidiDeviceListener.Stub {
         private final DeviceCallback mCallback;
         private final Handler mHandler;
+        private final int mTransport;
 
-        public DeviceListener(DeviceCallback callback, Handler handler) {
+        DeviceListener(DeviceCallback callback, Handler handler, int transport) {
             mCallback = callback;
             mHandler = handler;
+            mTransport = transport;
         }
 
         @Override
         public void onDeviceAdded(MidiDeviceInfo device) {
-            if (mHandler != null) {
-                final MidiDeviceInfo deviceF = device;
-                mHandler.post(new Runnable() {
-                        @Override public void run() {
-                            mCallback.onDeviceAdded(deviceF);
-                        }
-                    });
-            } else {
-                mCallback.onDeviceAdded(device);
+            if (shouldInvokeCallback(device)) {
+                if (mHandler != null) {
+                    final MidiDeviceInfo deviceF = device;
+                    mHandler.post(new Runnable() {
+                            @Override public void run() {
+                                mCallback.onDeviceAdded(deviceF);
+                            }
+                        });
+                } else {
+                    mCallback.onDeviceAdded(device);
+                }
             }
         }
 
         @Override
         public void onDeviceRemoved(MidiDeviceInfo device) {
-            if (mHandler != null) {
-                final MidiDeviceInfo deviceF = device;
-                mHandler.post(new Runnable() {
-                        @Override public void run() {
-                            mCallback.onDeviceRemoved(deviceF);
-                        }
-                    });
-            } else {
-                mCallback.onDeviceRemoved(device);
+            if (shouldInvokeCallback(device)) {
+                if (mHandler != null) {
+                    final MidiDeviceInfo deviceF = device;
+                    mHandler.post(new Runnable() {
+                            @Override public void run() {
+                                mCallback.onDeviceRemoved(deviceF);
+                            }
+                        });
+                } else {
+                    mCallback.onDeviceRemoved(device);
+                }
             }
         }
 
@@ -115,6 +161,25 @@ public final class MidiManager {
                 mCallback.onDeviceStatusChanged(status);
             }
         }
+
+        /**
+         * Used to figure out whether callbacks should be invoked. Only invoke callbacks of
+         * the correct type.
+         *
+         * @param MidiDeviceInfo the device to check
+         * @return whether to invoke a callback
+         */
+        private boolean shouldInvokeCallback(MidiDeviceInfo device) {
+            // UMP devices have protocols that are not PROTOCOL_UNKNOWN
+            if (mTransport == TRANSPORT_UNIVERSAL_MIDI_PACKETS) {
+                return (device.getDefaultProtocol() != MidiDeviceInfo.PROTOCOL_UNKNOWN);
+            } else if (mTransport == TRANSPORT_MIDI_BYTE_STREAM) {
+                return (device.getDefaultProtocol() == MidiDeviceInfo.PROTOCOL_UNKNOWN);
+            } else {
+                Log.e(TAG, "Invalid transport type: " + mTransport);
+                return false;
+            }
+        }
     }
 
     /**
@@ -167,8 +232,10 @@ public final class MidiManager {
     }
 
     /**
-     * Registers a callback to receive notifications when MIDI devices are added and removed.
-     *
+     * Registers a callback to receive notifications when MIDI 1.0 devices are added and removed.
+     * These are devices that do not default to Universal MIDI Packets. To register for a callback
+     * for those, call {@link #registerDeviceCallbackForTransport} instead.
+
      * The {@link  DeviceCallback#onDeviceStatusChanged} method will be called immediately
      * for any devices that have open ports. This allows applications to know which input
      * ports are already in use and, therefore, unavailable.
@@ -182,7 +249,30 @@ public final class MidiManager {
      *                callback is unspecified.
      */
     public void registerDeviceCallback(DeviceCallback callback, Handler handler) {
-        DeviceListener deviceListener = new DeviceListener(callback, handler);
+        registerDeviceCallbackForTransport(callback, handler, TRANSPORT_MIDI_BYTE_STREAM);
+    }
+
+    /**
+     * Registers a callback to receive notifications when MIDI devices are added and removed
+     * for a specific transport type.
+     *
+     * The {@link  DeviceCallback#onDeviceStatusChanged} method will be called immediately
+     * for any devices that have open ports. This allows applications to know which input
+     * ports are already in use and, therefore, unavailable.
+     *
+     * Applications should call {@link #getDevicesForTransport} before registering the callback
+     * to get a list of devices already added.
+     *
+     * @param callback a {@link DeviceCallback} for MIDI device notifications
+     * @param handler The {@link android.os.Handler Handler} that will be used for delivering the
+     *                device notifications. If handler is null, then the thread used for the
+     *                callback is unspecified.
+     * @param transport The transport to be used. This is either TRANSPORT_MIDI_BYTE_STREAM or
+     *            TRANSPORT_UNIVERSAL_MIDI_PACKETS.
+     */
+    public void registerDeviceCallbackForTransport(@NonNull DeviceCallback callback,
+            @Nullable Handler handler, @Transport int transport) {
+        DeviceListener deviceListener = new DeviceListener(callback, handler, transport);
         try {
             mService.registerListener(mToken, deviceListener);
         } catch (RemoteException e) {
@@ -208,9 +298,11 @@ public final class MidiManager {
     }
 
     /**
-     * Gets the list of all connected MIDI devices.
+     * Gets a list of connected MIDI devices. This returns all devices that do
+     * not default to Universal MIDI Packets. To get those instead, please call
+     * {@link #getDevicesForTransport} instead.
      *
-     * @return an array of all MIDI devices
+     * @return an array of MIDI devices
      */
     public MidiDeviceInfo[] getDevices() {
         try {
@@ -220,6 +312,29 @@ public final class MidiManager {
         }
     }
 
+    /**
+     * Gets a list of connected MIDI devices by transport. TRANSPORT_MIDI_BYTE_STREAM
+     * is used for MIDI 1.0 and is the most common.
+     * For devices with built in Universal MIDI Packet support, use
+     * TRANSPORT_UNIVERSAL_MIDI_PACKETS instead.
+     *
+     * @param transport The transport to be used. This is either TRANSPORT_MIDI_BYTE_STREAM or
+     *                  TRANSPORT_UNIVERSAL_MIDI_PACKETS.
+     * @return a collection of MIDI devices
+     */
+    public @NonNull Collection<MidiDeviceInfo> getDevicesForTransport(@Transport int transport) {
+        try {
+            MidiDeviceInfo[] devices = mService.getDevicesForTransport(transport);
+            Collection<MidiDeviceInfo> out = new ArrayList<MidiDeviceInfo>(devices.length);
+            for (int i = 0; i < devices.length; i++) {
+                out.add(devices[i]);
+            }
+            return out;
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
     private void sendOpenDeviceResponse(final MidiDevice device,
             final OnDeviceOpenedListener listener, Handler handler) {
         if (handler != null) {
@@ -311,13 +426,14 @@ public final class MidiManager {
     /** @hide */
     public MidiDeviceServer createDeviceServer(MidiReceiver[] inputPortReceivers,
             int numOutputPorts, String[] inputPortNames, String[] outputPortNames,
-            Bundle properties, int type, MidiDeviceServer.Callback callback) {
+            Bundle properties, int type, int defaultProtocol,
+            MidiDeviceServer.Callback callback) {
         try {
             MidiDeviceServer server = new MidiDeviceServer(mService, inputPortReceivers,
                     numOutputPorts, callback);
             MidiDeviceInfo deviceInfo = mService.registerDeviceServer(server.getBinderInterface(),
                     inputPortReceivers.length, numOutputPorts, inputPortNames, outputPortNames,
-                    properties, type);
+                    properties, type, defaultProtocol);
             if (deviceInfo == null) {
                 Log.e(TAG, "registerVirtualDevice failed");
                 return null;
diff --git a/media/java/android/media/midi/package.html b/media/java/android/media/midi/package.html
index 33c54900cd07e..67df1b2fa3157 100644
--- a/media/java/android/media/midi/package.html
+++ b/media/java/android/media/midi/package.html
@@ -405,5 +405,46 @@ apps using the
 <a href="#get_list_of_already_plugged_in_entities">MIDI device discovery calls described above</a>.
 </p>
 
+<h1 id=using_midi_2_0_over_usb>Using MIDI 2.0 over USB</h1>
+
+<p>An app can use MIDI 2.0 over USB starting in Android T. MIDI 2.0 packets are embedded in
+Universal MIDI Packets, or UMP for short. A MIDI 2.0 USB device should create two interfaces,
+one endpoint that accepts only MIDI 1.0 packets and one that accepts only UMP packets.
+For more info about MIDI 2.0 and UMP, please read the MIDI 2.0 USB spec.</p>
+
+<p>MidiManager.getDevices() would simply return the 1.0 interface. This interface should work
+exactly the same as before. In order to use the new UMP interface, retrieve the device with the
+following code snippet.</p>
+
+<pre class=prettyprint>
+Collection&#60;MidiDeviceInfo&#62; universalDeviceInfos = midiManager.getDevicesForTransport(
+        MidiManager.TRANSPORT_UNIVERSAL_MIDI_PACKETS);
+</pre>
+
+<p>UMP Packets are always in multiple of 4 bytes. For each set of 4 bytes, they are sent in network
+order. Compare the following NoteOn code snippet with the NoteOn code snippet above. </p>
+
+<pre class=prettyprint>
+byte[] buffer = new byte[32];
+int numBytes = 0;
+int channel = 3; // MIDI channels 1-16 are encoded as 0-15.
+int group = 0;
+buffer[numBytes++] = (byte)(0x20 + group); // MIDI 1.0 voice message
+buffer[numBytes++] = (byte)(0x90 + (channel - 1)); // note on
+buffer[numBytes++] = (byte)60; // pitch is middle C
+buffer[numBytes++] = (byte)127; // max velocity
+int offset = 0;
+// post is non-blocking
+inputPort.send(buffer, offset, numBytes);
+</pre>
+
+<p>MIDI 2.0 messages can be sent through UMP after negotiating with the device. This is called
+MIDI-CI and is documented in the MIDI 2.0 spec. Some USB devices support pre-negotiated MIDI 2.0.
+For a MidiDeviceInfo, you can query the defaultProtocol.</p>
+
+<pre class=prettyprint>
+int defaultProtocol = info.getDefaultProtocol();
+</pre>
+
 </body>
 </html>
diff --git a/media/native/midi/MidiDeviceInfo.cpp b/media/native/midi/MidiDeviceInfo.cpp
index 8a573fba322b1..14524883470f4 100644
--- a/media/native/midi/MidiDeviceInfo.cpp
+++ b/media/native/midi/MidiDeviceInfo.cpp
@@ -64,6 +64,7 @@ status_t MidiDeviceInfo::writeToParcel(Parcel* parcel) const {
     RETURN_IF_FAILED(writeStringVector(parcel, mInputPortNames));
     RETURN_IF_FAILED(writeStringVector(parcel, mOutputPortNames));
     RETURN_IF_FAILED(parcel->writeInt32(mIsPrivate ? 1 : 0));
+    RETURN_IF_FAILED(parcel->writeInt32(mDefaultProtocol));
     RETURN_IF_FAILED(mProperties.writeToParcel(parcel));
     // This corresponds to "extra" properties written by Java code
     RETURN_IF_FAILED(mProperties.writeToParcel(parcel));
@@ -83,6 +84,7 @@ status_t MidiDeviceInfo::readFromParcel(const Parcel* parcel) {
     int32_t isPrivate;
     RETURN_IF_FAILED(parcel->readInt32(&isPrivate));
     mIsPrivate = isPrivate == 1;
+    RETURN_IF_FAILED(parcel->readInt32(&mDefaultProtocol));
     RETURN_IF_FAILED(mProperties.readFromParcel(parcel));
     // Ignore "extra" properties as they may contain Java Parcelables
     return OK;
@@ -130,7 +132,8 @@ bool operator==(const MidiDeviceInfo& lhs, const MidiDeviceInfo& rhs) {
             areVectorsEqual(lhs.mInputPortNames, rhs.mInputPortNames) &&
             areVectorsEqual(lhs.mOutputPortNames, rhs.mOutputPortNames) &&
             lhs.mProperties == rhs.mProperties &&
-            lhs.mIsPrivate == rhs.mIsPrivate);
+            lhs.mIsPrivate == rhs.mIsPrivate &&
+            lhs.mDefaultProtocol == rhs.mDefaultProtocol);
 }
 
 }  // namespace midi
diff --git a/media/native/midi/MidiDeviceInfo.h b/media/native/midi/MidiDeviceInfo.h
index 5b4a241323d71..23e1cb4741685 100644
--- a/media/native/midi/MidiDeviceInfo.h
+++ b/media/native/midi/MidiDeviceInfo.h
@@ -38,6 +38,7 @@ public:
     int getType() const { return mType; }
     int getUid() const { return mId; }
     bool isPrivate() const { return mIsPrivate; }
+    int getDefaultProtocol() const { return mDefaultProtocol; }
     const Vector<String16>& getInputPortNames() const { return mInputPortNames; }
     const Vector<String16>&  getOutputPortNames() const { return mOutputPortNames; }
     String16 getProperty(const char* propertyName);
@@ -48,6 +49,18 @@ public:
         TYPE_VIRTUAL = 2,
         TYPE_BLUETOOTH = 3,
     };
+
+    enum {
+        PROTOCOL_UMP_USE_MIDI_CI = 0,
+        PROTOCOL_UMP_MIDI_1_0_UP_TO_64_BITS = 1,
+        PROTOCOL_UMP_MIDI_1_0_UP_TO_64_BITS_AND_JRTS = 2,
+        PROTOCOL_UMP_MIDI_1_0_UP_TO_128_BITS = 3,
+        PROTOCOL_UMP_MIDI_1_0_UP_TO_128_BITS_AND_JRTS = 4,
+        PROTOCOL_UMP_MIDI_2_0 = 17,
+        PROTOCOL_UMP_MIDI_2_0_AND_JRTS = 18,
+        PROTOCOL_UNKNOWN = -1,
+    };
+
     static const char* const PROPERTY_NAME;
     static const char* const PROPERTY_MANUFACTURER;
     static const char* const PROPERTY_PRODUCT;
@@ -72,6 +85,7 @@ private:
     Vector<String16> mOutputPortNames;
     os::PersistableBundle mProperties;
     bool mIsPrivate;
+    int32_t mDefaultProtocol;
 };
 
 }  // namespace midi
diff --git a/media/native/midi/amidi.cpp b/media/native/midi/amidi.cpp
index f90796e415c0c..aa076e85e30d2 100644
--- a/media/native/midi/amidi.cpp
+++ b/media/native/midi/amidi.cpp
@@ -138,6 +138,7 @@ static media_status_t AMIDI_getDeviceInfo(const AMidiDevice *device,
     outDeviceInfoPtr->type = deviceInfo.getType();
     outDeviceInfoPtr->inputPortCount = deviceInfo.getInputPortNames().size();
     outDeviceInfoPtr->outputPortCount = deviceInfo.getOutputPortNames().size();
+    outDeviceInfoPtr->defaultProtocol = deviceInfo.getDefaultProtocol();
 
     return AMEDIA_OK;
 }
@@ -238,6 +239,13 @@ ssize_t AMIDI_API AMidiDevice_getNumOutputPorts(const AMidiDevice *device) {
     return device->deviceInfo.outputPortCount;
 }
 
+AMidiDevice_Protocol AMIDI_API AMidiDevice_getDefaultProtocol(const AMidiDevice *device) {
+    if (device == nullptr) {
+        return AMIDI_DEVICE_PROTOCOL_UNKNOWN;
+    }
+    return static_cast<AMidiDevice_Protocol>(device->deviceInfo.defaultProtocol);
+}
+
 /*
  * Port Helpers
  */
diff --git a/media/native/midi/amidi_internal.h b/media/native/midi/amidi_internal.h
index fce85963d2179..023a6f5ec9008 100644
--- a/media/native/midi/amidi_internal.h
+++ b/media/native/midi/amidi_internal.h
@@ -25,6 +25,7 @@ typedef struct {
     int32_t type;            /* one of AMIDI_DEVICE_TYPE_* constants */
     int32_t inputPortCount;  /* number of input (send) ports associated with the device */
     int32_t outputPortCount; /* number of output (received) ports associated with the device */
+    int32_t defaultProtocol; /* one of the AMIDI_DEVICE_PROTOCOL_* constants */
 } AMidiDeviceInfo;
 
 struct AMidiDevice {
diff --git a/media/native/midi/include/amidi/AMidi.h b/media/native/midi/include/amidi/AMidi.h
index 742db34b74a74..fbb7fb329659d 100644
--- a/media/native/midi/include/amidi/AMidi.h
+++ b/media/native/midi/include/amidi/AMidi.h
@@ -61,6 +61,78 @@ enum {
     AMIDI_DEVICE_TYPE_BLUETOOTH = 3 /* A MIDI device connected via BlueTooth */
 };
 
+/*
+ * Protocol IDs for various MIDI devices.
+ *
+ * Introduced in API 33.
+ */
+enum AMidiDevice_Protocol : int32_t {
+    /**
+     * Constant representing a default protocol with Universal MIDI Packets (UMP).
+     * UMP is defined in "Universal MIDI Packet (UMP) Format and MIDI 2.0 Protocol" spec.
+     * All UMP data should be a multiple of 4 bytes.
+     * Use UMP to negotiate with the device with MIDI-CI.
+     * MIDI-CI is defined in "MIDI Capability Inquiry (MIDI-CI)" spec.
+     */
+    AMIDI_DEVICE_PROTOCOL_UMP_USE_MIDI_CI = 0,
+
+    /**
+     * Constant representing a default protocol with Universal MIDI Packets (UMP).
+     * UMP is defined in "Universal MIDI Packet (UMP) Format and MIDI 2.0 Protocol" spec.
+     * All UMP data should be a multiple of 4 bytes.
+     * Use MIDI 1.0 through UMP with packet sizes up to 64 bits.
+     */
+    AMIDI_DEVICE_PROTOCOL_UMP_MIDI_1_0_UP_TO_64_BITS = 1,
+
+    /**
+     * Constant representing a default protocol with Universal MIDI Packets (UMP).
+     * UMP is defined in "Universal MIDI Packet (UMP) Format and MIDI 2.0 Protocol" spec.
+     * All UMP data should be a multiple of 4 bytes.
+     * Use MIDI 1.0 through UMP with packet sizes up to 64 bits and jitter reduction timestamps.
+     */
+    AMIDI_DEVICE_PROTOCOL_UMP_MIDI_1_0_UP_TO_64_BITS_AND_JRTS = 2,
+
+    /**
+     * Constant representing a default protocol with Universal MIDI Packets (UMP).
+     * UMP is defined in "Universal MIDI Packet (UMP) Format and MIDI 2.0 Protocol" spec.
+     * All UMP data should be a multiple of 4 bytes.
+     * Use MIDI 1.0 through UMP with packet sizes up to 128 bits.
+     */
+    AMIDI_DEVICE_PROTOCOL_UMP_MIDI_1_0_UP_TO_128_BITS = 3,
+
+    /**
+     * Constant representing a default protocol with Universal MIDI Packets (UMP).
+     * UMP is defined in "Universal MIDI Packet (UMP) Format and MIDI 2.0 Protocol" spec.
+     * All UMP data should be a multiple of 4 bytes.
+     * Use MIDI 1.0 through UMP with packet sizes up to 128 bits and jitter reduction timestamps.
+     */
+    AMIDI_DEVICE_PROTOCOL_UMP_MIDI_1_0_UP_TO_128_BITS_AND_JRTS = 4,
+
+    /**
+     * Constant representing a default protocol with Universal MIDI Packets (UMP).
+     * UMP is defined in "Universal MIDI Packet (UMP) Format and MIDI 2.0 Protocol" spec.
+     * All UMP data should be a multiple of 4 bytes.
+     * Use MIDI 2.0 through UMP.
+     */
+    AMIDI_DEVICE_PROTOCOL_UMP_MIDI_2_0 = 17,
+
+     /**
+     * Constant representing a default protocol with Universal MIDI Packets (UMP).
+     * UMP is defined in "Universal MIDI Packet (UMP) Format and MIDI 2.0 Protocol" spec.
+     * All UMP data should be a multiple of 4 bytes.
+     * Use MIDI 2.0 through UMP and jitter reduction timestamps.
+     */
+    AMIDI_DEVICE_PROTOCOL_UMP_MIDI_2_0_AND_JRTS = 18,
+
+    /**
+     * Constant representing a device with an unknown default protocol.
+     * If Universal MIDI Packets (UMP) are needed, use MIDI-CI through MIDI 1.0.
+     * UMP is defined in "Universal MIDI Packet (UMP) Format and MIDI 2.0 Protocol" spec.
+     * MIDI-CI is defined in "MIDI Capability Inquiry (MIDI-CI)" spec.
+     */
+    AMIDI_DEVICE_PROTOCOL_UNKNOWN = -1
+};
+
 /*
  * Device API
  */
@@ -134,6 +206,30 @@ ssize_t AMIDI_API AMidiDevice_getNumInputPorts(const AMidiDevice *device) __INTR
  */
 ssize_t AMIDI_API AMidiDevice_getNumOutputPorts(const AMidiDevice *device) __INTRODUCED_IN(29);
 
+/**
+ * Gets the MIDI device default protocol.
+ *
+ * @param device Specifies the MIDI device.
+ *
+ * @return The identifier of the MIDI device default protocol:
+ * AMIDI_DEVICE_PROTOCOL_UMP_USE_MIDI_CI
+ * AMIDI_DEVICE_PROTOCOL_UMP_MIDI_1_0_UP_TO_64_BITS
+ * AMIDI_DEVICE_PROTOCOL_UMP_MIDI_1_0_UP_TO_64_BITS_AND_JRTS
+ * AMIDI_DEVICE_PROTOCOL_UMP_MIDI_1_0_UP_TO_128_BITS
+ * AMIDI_DEVICE_PROTOCOL_UMP_MIDI_1_0_UP_TO_128_BITS_AND_JRTS
+ * AMIDI_DEVICE_PROTOCOL_UMP_MIDI_2_0
+ * AMIDI_DEVICE_PROTOCOL_UMP_MIDI_2_0_AND_JRTS
+ * AMIDI_DEVICE_PROTOCOL_UNKNOWN
+ *
+ * Most devices should return PROTOCOL_UNKNOWN (-1). This is intentional as devices
+ * with default UMP support are not backwards compatible. When the device is null,
+ * return AMIDI_DEVICE_PROTOCOL_UNKNOWN.
+ *
+ * Available since API 33.
+ */
+AMidiDevice_Protocol AMIDI_API AMidiDevice_getDefaultProtocol(const AMidiDevice *device)
+        __INTRODUCED_IN(33);
+
 /*
  * API for receiving data from the Output port of a device.
  */
diff --git a/media/native/midi/libamidi.map.txt b/media/native/midi/libamidi.map.txt
index 62627f8c5ef78..f25f97770b50a 100644
--- a/media/native/midi/libamidi.map.txt
+++ b/media/native/midi/libamidi.map.txt
@@ -2,6 +2,7 @@ LIBAMIDI {
   global:
     AMidiDevice_fromJava;
     AMidiDevice_release;
+    AMidiDevice_getDefaultProtocol; # introduced=Tiramisu
     AMidiDevice_getType;
     AMidiDevice_getNumInputPorts;
     AMidiDevice_getNumOutputPorts;
diff --git a/media/packages/BluetoothMidiService/src/com/android/bluetoothmidiservice/BluetoothMidiDevice.java b/media/packages/BluetoothMidiService/src/com/android/bluetoothmidiservice/BluetoothMidiDevice.java
index 62c313ace306a..2dd9525867b6b 100644
--- a/media/packages/BluetoothMidiService/src/com/android/bluetoothmidiservice/BluetoothMidiDevice.java
+++ b/media/packages/BluetoothMidiService/src/com/android/bluetoothmidiservice/BluetoothMidiDevice.java
@@ -260,7 +260,8 @@ public final class BluetoothMidiDevice {
         inputPortReceivers[0] = mEventScheduler.getReceiver();
 
         mDeviceServer = mMidiManager.createDeviceServer(inputPortReceivers, 1,
-                null, null, properties, MidiDeviceInfo.TYPE_BLUETOOTH, mDeviceServerCallback);
+                null, null, properties, MidiDeviceInfo.TYPE_BLUETOOTH,
+                MidiDeviceInfo.PROTOCOL_UNKNOWN, mDeviceServerCallback);
 
         mOutputReceiver = mDeviceServer.getOutputPortReceivers()[0];
 
diff --git a/services/midi/java/com/android/server/midi/MidiService.java b/services/midi/java/com/android/server/midi/MidiService.java
index ca31efcdf3d2a..715fe6e5f85e2 100644
--- a/services/midi/java/com/android/server/midi/MidiService.java
+++ b/services/midi/java/com/android/server/midi/MidiService.java
@@ -643,13 +643,31 @@ public class MidiService extends IMidiManager.Stub {
     private static final MidiDeviceInfo[] EMPTY_DEVICE_INFO_ARRAY = new MidiDeviceInfo[0];
 
     public MidiDeviceInfo[] getDevices() {
+        return getDevicesForTransport(MidiManager.TRANSPORT_MIDI_BYTE_STREAM);
+    }
+
+    /**
+    * @hide
+    */
+    public MidiDeviceInfo[] getDevicesForTransport(int transport) {
         ArrayList<MidiDeviceInfo> deviceInfos = new ArrayList<MidiDeviceInfo>();
         int uid = Binder.getCallingUid();
 
         synchronized (mDevicesByInfo) {
             for (Device device : mDevicesByInfo.values()) {
                 if (device.isUidAllowed(uid)) {
-                    deviceInfos.add(device.getDeviceInfo());
+                    // UMP devices have protocols that are not PROTOCOL_UNKNOWN
+                    if (transport == MidiManager.TRANSPORT_UNIVERSAL_MIDI_PACKETS) {
+                        if (device.getDeviceInfo().getDefaultProtocol()
+                                != MidiDeviceInfo.PROTOCOL_UNKNOWN) {
+                            deviceInfos.add(device.getDeviceInfo());
+                        }
+                    } else if (transport == MidiManager.TRANSPORT_MIDI_BYTE_STREAM) {
+                        if (device.getDeviceInfo().getDefaultProtocol()
+                                == MidiDeviceInfo.PROTOCOL_UNKNOWN) {
+                            deviceInfos.add(device.getDeviceInfo());
+                        }
+                    }
                 }
             }
         }
@@ -718,7 +736,7 @@ public class MidiService extends IMidiManager.Stub {
     @Override
     public MidiDeviceInfo registerDeviceServer(IMidiDeviceServer server, int numInputPorts,
             int numOutputPorts, String[] inputPortNames, String[] outputPortNames,
-            Bundle properties, int type) {
+            Bundle properties, int type, int defaultProtocol) {
         int uid = Binder.getCallingUid();
         if (type == MidiDeviceInfo.TYPE_USB && uid != Process.SYSTEM_UID) {
             throw new SecurityException("only system can create USB devices");
@@ -728,7 +746,8 @@ public class MidiService extends IMidiManager.Stub {
 
         synchronized (mDevicesByInfo) {
             return addDeviceLocked(type, numInputPorts, numOutputPorts, inputPortNames,
-                    outputPortNames, properties, server, null, false, uid);
+                    outputPortNames, properties, server, null, false, uid,
+                    defaultProtocol);
         }
     }
 
@@ -797,11 +816,12 @@ public class MidiService extends IMidiManager.Stub {
     private MidiDeviceInfo addDeviceLocked(int type, int numInputPorts, int numOutputPorts,
             String[] inputPortNames, String[] outputPortNames, Bundle properties,
             IMidiDeviceServer server, ServiceInfo serviceInfo,
-            boolean isPrivate, int uid) {
+            boolean isPrivate, int uid, int defaultProtocol) {
 
         int id = mNextDeviceId++;
         MidiDeviceInfo deviceInfo = new MidiDeviceInfo(type, id, numInputPorts, numOutputPorts,
-                inputPortNames, outputPortNames, properties, isPrivate);
+                inputPortNames, outputPortNames, properties, isPrivate,
+                defaultProtocol);
 
         if (server != null) {
             try {
@@ -988,10 +1008,11 @@ public class MidiService extends IMidiManager.Stub {
 
                             synchronized (mDevicesByInfo) {
                                 addDeviceLocked(MidiDeviceInfo.TYPE_VIRTUAL,
-                                    numInputPorts, numOutputPorts,
-                                    inputPortNames.toArray(EMPTY_STRING_ARRAY),
-                                    outputPortNames.toArray(EMPTY_STRING_ARRAY),
-                                    properties, null, serviceInfo, isPrivate, uid);
+                                        numInputPorts, numOutputPorts,
+                                        inputPortNames.toArray(EMPTY_STRING_ARRAY),
+                                        outputPortNames.toArray(EMPTY_STRING_ARRAY),
+                                        properties, null, serviceInfo, isPrivate, uid,
+                                        MidiDeviceInfo.PROTOCOL_UNKNOWN);
                             }
                             // setting properties to null signals that we are no longer
                             // processing a <device>
diff --git a/services/usb/java/com/android/server/usb/UsbAlsaManager.java b/services/usb/java/com/android/server/usb/UsbAlsaManager.java
index 0aa62c53e269f..1c72eb8db708b 100644
--- a/services/usb/java/com/android/server/usb/UsbAlsaManager.java
+++ b/services/usb/java/com/android/server/usb/UsbAlsaManager.java
@@ -257,10 +257,11 @@ public final class UsbAlsaManager {
 
         // look for MIDI devices
         boolean hasMidi = parser.hasMIDIInterface();
-        int midiNumInputs = parser.calculateNumMidiInputs();
-        int midiNumOutputs = parser.calculateNumMidiOutputs();
+        int midiNumInputs = parser.calculateNumLegacyMidiInputs();
+        int midiNumOutputs = parser.calculateNumLegacyMidiOutputs();
         if (DEBUG) {
             Slog.d(TAG, "hasMidi: " + hasMidi + " mHasMidiFeature:" + mHasMidiFeature);
+            Slog.d(TAG, "midiNumInputs: " + midiNumInputs + " midiNumOutputs:" + midiNumOutputs);
         }
         if (hasMidi && mHasMidiFeature) {
             int device = 0;
diff --git a/services/usb/java/com/android/server/usb/UsbHostManager.java b/services/usb/java/com/android/server/usb/UsbHostManager.java
index f33001c9241e4..9ac270f17fc49 100644
--- a/services/usb/java/com/android/server/usb/UsbHostManager.java
+++ b/services/usb/java/com/android/server/usb/UsbHostManager.java
@@ -23,6 +23,7 @@ import android.annotation.NonNull;
 import android.annotation.Nullable;
 import android.content.ComponentName;
 import android.content.Context;
+import android.content.pm.PackageManager;
 import android.hardware.usb.UsbConstants;
 import android.hardware.usb.UsbDevice;
 import android.os.Bundle;
@@ -46,6 +47,8 @@ import com.android.server.usb.descriptors.UsbInterfaceDescriptor;
 import com.android.server.usb.descriptors.report.TextReportCanvas;
 import com.android.server.usb.descriptors.tree.UsbDescriptorsTree;
 
+import libcore.io.IoUtils;
+
 import java.text.SimpleDateFormat;
 import java.util.Date;
 import java.util.HashMap;
@@ -90,6 +93,13 @@ public class UsbHostManager {
     private ConnectionRecord mLastConnect;
     private final ArrayMap<String, ConnectionRecord> mConnected = new ArrayMap<>();
 
+    /**
+     * List of connected MIDI devices
+     */
+    private final HashMap<String, UsbUniversalMidiDevice>
+            mMidiDevices = new HashMap<String, UsbUniversalMidiDevice>();
+    private final boolean mHasMidiFeature;
+
     /*
      * ConnectionRecord
      * Stores connection/disconnection data.
@@ -245,6 +255,7 @@ public class UsbHostManager {
             setUsbDeviceConnectionHandler(ComponentName.unflattenFromString(
                     deviceConnectionHandler));
         }
+        mHasMidiFeature = context.getPackageManager().hasSystemFeature(PackageManager.FEATURE_MIDI);
     }
 
     public void setCurrentUserSettings(UsbProfileGroupSettingsManager settings) {
@@ -413,6 +424,18 @@ public class UsbHostManager {
 
                 mUsbAlsaManager.usbDeviceAdded(deviceAddress, newDevice, parser);
 
+                if (mHasMidiFeature) {
+                    if (parser.containsUniversalMidiDeviceEndpoint()) {
+                        UsbUniversalMidiDevice midiDevice = UsbUniversalMidiDevice.create(mContext,
+                                newDevice, parser);
+                        if (midiDevice != null) {
+                            mMidiDevices.put(deviceAddress, midiDevice);
+                        } else {
+                            Slog.e(TAG, "Universal Midi Device is null.");
+                        }
+                    }
+                }
+
                 // Tracking
                 addConnectionRecord(deviceAddress, ConnectionRecord.CONNECT,
                         parser.getRawDescriptors());
@@ -446,6 +469,14 @@ public class UsbHostManager {
                 Slog.d(TAG, "Removed device at " + deviceAddress + ": " + device.getProductName());
                 mUsbAlsaManager.usbDeviceRemoved(deviceAddress);
                 mPermissionManager.usbDeviceRemoved(device);
+
+                // MIDI
+                UsbUniversalMidiDevice midiDevice = mMidiDevices.remove(deviceAddress);
+                if (midiDevice != null) {
+                    Slog.i(TAG, "USB Universal MIDI Device Removed: " + deviceAddress);
+                    IoUtils.closeQuietly(midiDevice);
+                }
+
                 getCurrentUserSettings().usbDeviceRemoved(device);
                 ConnectionRecord current = mConnected.get(deviceAddress);
                 // Tracking
diff --git a/services/usb/java/com/android/server/usb/UsbMidiDevice.java b/services/usb/java/com/android/server/usb/UsbMidiDevice.java
index b61e93b36e58f..275f217551412 100644
--- a/services/usb/java/com/android/server/usb/UsbMidiDevice.java
+++ b/services/usb/java/com/android/server/usb/UsbMidiDevice.java
@@ -303,7 +303,8 @@ public final class UsbMidiDevice implements Closeable {
         }
 
         mServer = midiManager.createDeviceServer(mMidiInputPortReceivers, mNumInputs,
-                null, null, properties, MidiDeviceInfo.TYPE_USB, mCallback);
+                null, null, properties, MidiDeviceInfo.TYPE_USB,
+                MidiDeviceInfo.PROTOCOL_UNKNOWN, mCallback);
         if (mServer == null) {
             return false;
         }
diff --git a/services/usb/java/com/android/server/usb/UsbUniversalMidiDevice.java b/services/usb/java/com/android/server/usb/UsbUniversalMidiDevice.java
new file mode 100644
index 0000000000000..db0c80f189d3e
--- /dev/null
+++ b/services/usb/java/com/android/server/usb/UsbUniversalMidiDevice.java
@@ -0,0 +1,469 @@
+/*
+ * Copyright (C) 2021 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.server.usb;
+
+import android.content.Context;
+import android.hardware.usb.UsbDevice;
+import android.hardware.usb.UsbDeviceConnection;
+import android.hardware.usb.UsbEndpoint;
+import android.hardware.usb.UsbManager;
+import android.media.midi.MidiDeviceInfo;
+import android.media.midi.MidiDeviceServer;
+import android.media.midi.MidiDeviceStatus;
+import android.media.midi.MidiManager;
+import android.media.midi.MidiReceiver;
+import android.os.Bundle;
+import android.util.Log;
+
+import com.android.internal.midi.MidiEventScheduler;
+import com.android.internal.midi.MidiEventScheduler.MidiEvent;
+import com.android.server.usb.descriptors.UsbDescriptorParser;
+import com.android.server.usb.descriptors.UsbEndpointDescriptor;
+import com.android.server.usb.descriptors.UsbInterfaceDescriptor;
+import com.android.server.usb.descriptors.UsbMidiBlockParser;
+
+import libcore.io.IoUtils;
+
+import java.io.Closeable;
+import java.io.IOException;
+import java.util.ArrayList;
+
+/**
+ * A MIDI device that opens device connections to MIDI 2.0 endpoints.
+ */
+public final class UsbUniversalMidiDevice implements Closeable {
+    private static final String TAG = "UsbUniversalMidiDevice";
+    private static final boolean DEBUG = false;
+
+    private Context mContext;
+    private UsbDevice mUsbDevice;
+    private UsbDescriptorParser mParser;
+    private ArrayList<UsbInterfaceDescriptor> mUsbInterfaces;
+
+    // USB outputs are MIDI inputs
+    private final InputReceiverProxy[] mMidiInputPortReceivers;
+    private final int mNumInputs;
+    private final int mNumOutputs;
+
+    private MidiDeviceServer mServer;
+
+    // event schedulers for each input port of the physical device
+    private MidiEventScheduler[] mEventSchedulers;
+
+    private ArrayList<UsbDeviceConnection> mUsbDeviceConnections;
+    private ArrayList<ArrayList<UsbEndpoint>> mInputUsbEndpoints;
+    private ArrayList<ArrayList<UsbEndpoint>> mOutputUsbEndpoints;
+
+    private UsbMidiBlockParser mMidiBlockParser = new UsbMidiBlockParser();
+    private int mDefaultMidiProtocol = MidiDeviceInfo.PROTOCOL_UMP_MIDI_1_0_UP_TO_64_BITS;
+
+    private final Object mLock = new Object();
+    private boolean mIsOpen;
+
+    private final MidiDeviceServer.Callback mCallback = new MidiDeviceServer.Callback() {
+
+        @Override
+        public void onDeviceStatusChanged(MidiDeviceServer server, MidiDeviceStatus status) {
+            MidiDeviceInfo deviceInfo = status.getDeviceInfo();
+            int numInputPorts = deviceInfo.getInputPortCount();
+            int numOutputPorts = deviceInfo.getOutputPortCount();
+            boolean hasOpenPorts = false;
+
+            for (int i = 0; i < numInputPorts; i++) {
+                if (status.isInputPortOpen(i)) {
+                    hasOpenPorts = true;
+                    break;
+                }
+            }
+
+            if (!hasOpenPorts) {
+                for (int i = 0; i < numOutputPorts; i++) {
+                    if (status.getOutputPortOpenCount(i) > 0) {
+                        hasOpenPorts = true;
+                        break;
+                    }
+                }
+            }
+
+            synchronized (mLock) {
+                if (hasOpenPorts && !mIsOpen) {
+                    openLocked();
+                } else if (!hasOpenPorts && mIsOpen) {
+                    closeLocked();
+                }
+            }
+        }
+
+        @Override
+        public void onClose() {
+        }
+    };
+
+    // This class acts as a proxy for our MidiEventScheduler receivers, which do not exist
+    // until the device has active clients
+    private static final class InputReceiverProxy extends MidiReceiver {
+        private MidiReceiver mReceiver;
+
+        @Override
+        public void onSend(byte[] msg, int offset, int count, long timestamp) throws IOException {
+            MidiReceiver receiver = mReceiver;
+            if (receiver != null) {
+                receiver.send(msg, offset, count, timestamp);
+            }
+        }
+
+        public void setReceiver(MidiReceiver receiver) {
+            mReceiver = receiver;
+        }
+
+        @Override
+        public void onFlush() throws IOException {
+            MidiReceiver receiver = mReceiver;
+            if (receiver != null) {
+                receiver.flush();
+            }
+        }
+    }
+
+    /**
+     * Creates an UsbUniversalMidiDevice based on the input parameters. Read/Write streams
+     * will be created individually as some devices don't have the same number of
+     * inputs and outputs.
+     */
+    public static UsbUniversalMidiDevice create(Context context, UsbDevice usbDevice,
+            UsbDescriptorParser parser) {
+        UsbUniversalMidiDevice midiDevice = new UsbUniversalMidiDevice(usbDevice, parser);
+        if (!midiDevice.register(context)) {
+            IoUtils.closeQuietly(midiDevice);
+            Log.e(TAG, "createDeviceServer failed");
+            return null;
+        }
+        return midiDevice;
+    }
+
+    private UsbUniversalMidiDevice(UsbDevice usbDevice, UsbDescriptorParser parser) {
+        mUsbDevice = usbDevice;
+        mParser = parser;
+
+        mUsbInterfaces = parser.findUniversalMidiInterfaceDescriptors();
+
+        int numInputs = 0;
+        int numOutputs = 0;
+
+        for (int interfaceIndex = 0; interfaceIndex < mUsbInterfaces.size(); interfaceIndex++) {
+            UsbInterfaceDescriptor interfaceDescriptor = mUsbInterfaces.get(interfaceIndex);
+            for (int endpointIndex = 0; endpointIndex < interfaceDescriptor.getNumEndpoints();
+                    endpointIndex++) {
+                UsbEndpointDescriptor endpoint =
+                        interfaceDescriptor.getEndpointDescriptor(endpointIndex);
+                // 0 is output, 1 << 7 is input.
+                if (endpoint.getDirection() == 0) {
+                    numOutputs++;
+                } else {
+                    numInputs++;
+                }
+            }
+        }
+
+        mNumInputs = numInputs;
+        mNumOutputs = numOutputs;
+
+        Log.d(TAG, "Created UsbUniversalMidiDevice with " + numInputs + " inputs and "
+                + numOutputs + " outputs");
+
+        // Create MIDI port receivers based on the number of output ports. The
+        // output of USB is the input of MIDI.
+        mMidiInputPortReceivers = new InputReceiverProxy[numOutputs];
+        for (int port = 0; port < numOutputs; port++) {
+            mMidiInputPortReceivers[port] = new InputReceiverProxy();
+        }
+    }
+
+    private int calculateDefaultMidiProtocol() {
+        UsbManager manager = mContext.getSystemService(UsbManager.class);
+
+        for (int interfaceIndex = 0; interfaceIndex < mUsbInterfaces.size(); interfaceIndex++) {
+            UsbInterfaceDescriptor interfaceDescriptor = mUsbInterfaces.get(interfaceIndex);
+            boolean doesInterfaceContainInput = false;
+            boolean doesInterfaceContainOutput = false;
+            for (int endpointIndex = 0; (endpointIndex < interfaceDescriptor.getNumEndpoints())
+                    && !(doesInterfaceContainInput && doesInterfaceContainOutput);
+                    endpointIndex++) {
+                UsbEndpointDescriptor endpoint =
+                        interfaceDescriptor.getEndpointDescriptor(endpointIndex);
+                // 0 is output, 1 << 7 is input.
+                if (endpoint.getDirection() == 0) {
+                    doesInterfaceContainOutput = true;
+                } else {
+                    doesInterfaceContainInput = true;
+                }
+            }
+
+            // Intentionally open the device connection to query the default MIDI type for
+            // a connection with both the input and output set.
+            if (doesInterfaceContainInput
+                    && doesInterfaceContainOutput) {
+                UsbDeviceConnection connection = manager.openDevice(mUsbDevice);
+                if (!connection.claimInterface(interfaceDescriptor.toAndroid(mParser), true)) {
+                    Log.d(TAG, "Can't claim control interface");
+                    continue;
+                }
+                int defaultMidiProtocol = mMidiBlockParser.calculateMidiType(connection,
+                        interfaceDescriptor.getInterfaceNumber(),
+                        interfaceDescriptor.getAlternateSetting());
+
+                connection.close();
+                return defaultMidiProtocol;
+            }
+        }
+
+        Log.d(TAG, "Cannot find interface with both input and output endpoints");
+        return MidiDeviceInfo.PROTOCOL_UMP_MIDI_1_0_UP_TO_64_BITS;
+    }
+
+    private boolean openLocked() {
+        UsbManager manager = mContext.getSystemService(UsbManager.class);
+
+        mUsbDeviceConnections = new ArrayList<UsbDeviceConnection>(mUsbInterfaces.size());
+        mInputUsbEndpoints = new ArrayList<ArrayList<UsbEndpoint>>(mUsbInterfaces.size());
+        mOutputUsbEndpoints = new ArrayList<ArrayList<UsbEndpoint>>(mUsbInterfaces.size());
+
+        for (int interfaceIndex = 0; interfaceIndex < mUsbInterfaces.size(); interfaceIndex++) {
+            ArrayList<UsbEndpoint> inputEndpoints = new ArrayList<UsbEndpoint>();
+            ArrayList<UsbEndpoint> outputEndpoints = new ArrayList<UsbEndpoint>();
+            UsbInterfaceDescriptor interfaceDescriptor = mUsbInterfaces.get(interfaceIndex);
+            for (int endpointIndex = 0; endpointIndex < interfaceDescriptor.getNumEndpoints();
+                    endpointIndex++) {
+                UsbEndpointDescriptor endpoint =
+                        interfaceDescriptor.getEndpointDescriptor(endpointIndex);
+                // 0 is output, 1 << 7 is input.
+                if (endpoint.getDirection() == 0) {
+                    outputEndpoints.add(endpoint.toAndroid(mParser));
+                } else {
+                    inputEndpoints.add(endpoint.toAndroid(mParser));
+                }
+            }
+            if (!outputEndpoints.isEmpty() || !inputEndpoints.isEmpty()) {
+                UsbDeviceConnection connection = manager.openDevice(mUsbDevice);
+                connection.setInterface(interfaceDescriptor.toAndroid(mParser));
+                connection.claimInterface(interfaceDescriptor.toAndroid(mParser), true);
+                mUsbDeviceConnections.add(connection);
+                mInputUsbEndpoints.add(inputEndpoints);
+                mOutputUsbEndpoints.add(outputEndpoints);
+            }
+        }
+
+        mEventSchedulers = new MidiEventScheduler[mNumOutputs];
+
+        for (int i = 0; i < mNumOutputs; i++) {
+            MidiEventScheduler scheduler = new MidiEventScheduler();
+            mEventSchedulers[i] = scheduler;
+            mMidiInputPortReceivers[i].setReceiver(scheduler.getReceiver());
+        }
+
+        final MidiReceiver[] outputReceivers = mServer.getOutputPortReceivers();
+
+        // Create input thread for each input port of the physical device
+        int portNumber = 0;
+        for (int connectionIndex = 0; connectionIndex < mInputUsbEndpoints.size();
+                connectionIndex++) {
+            for (int endpointIndex = 0;
+                    endpointIndex < mInputUsbEndpoints.get(connectionIndex).size();
+                    endpointIndex++) {
+                final UsbDeviceConnection connectionF = mUsbDeviceConnections.get(connectionIndex);
+                final UsbEndpoint epF = mInputUsbEndpoints.get(connectionIndex).get(endpointIndex);
+                final int portF = portNumber;
+
+                new Thread("UsbUniversalMidiDevice input thread " + portF) {
+                    @Override
+                    public void run() {
+                        byte[] inputBuffer = new byte[epF.getMaxPacketSize()];
+                        try {
+                            while (true) {
+                                // Record time of event immediately after waking.
+                                long timestamp = System.nanoTime();
+                                synchronized (mLock) {
+                                    if (!mIsOpen) break;
+
+                                    int nRead = connectionF.bulkTransfer(epF, inputBuffer,
+                                            inputBuffer.length, 0);
+
+                                    // For USB, each 32 bit word of a UMP is
+                                    // sent with the least significant byte first.
+                                    swapEndiannessPerWord(inputBuffer, inputBuffer.length);
+
+                                    if (nRead > 0) {
+                                        if (DEBUG) {
+                                            logByteArray("Input ", inputBuffer, 0,
+                                                    nRead);
+                                        }
+                                        outputReceivers[portF].send(inputBuffer, 0, nRead,
+                                                timestamp);
+                                    }
+                                }
+                            }
+                        } catch (IOException e) {
+                            Log.d(TAG, "reader thread exiting");
+                        }
+                        Log.d(TAG, "input thread exit");
+                    }
+                }.start();
+
+                portNumber++;
+            }
+        }
+
+        // Create output thread for each output port of the physical device
+        portNumber = 0;
+        for (int connectionIndex = 0; connectionIndex < mOutputUsbEndpoints.size();
+                connectionIndex++) {
+            for (int endpointIndex = 0;
+                    endpointIndex < mOutputUsbEndpoints.get(connectionIndex).size();
+                    endpointIndex++) {
+                final UsbDeviceConnection connectionF = mUsbDeviceConnections.get(connectionIndex);
+                final UsbEndpoint epF =
+                        mOutputUsbEndpoints.get(connectionIndex).get(endpointIndex);
+                final int portF = portNumber;
+                final MidiEventScheduler eventSchedulerF = mEventSchedulers[portF];
+
+                new Thread("UsbUniversalMidiDevice output thread " + portF) {
+                    @Override
+                    public void run() {
+                        while (true) {
+                            MidiEvent event;
+                            try {
+                                event = (MidiEvent) eventSchedulerF.waitNextEvent();
+                            } catch (InterruptedException e) {
+                                // try again
+                                continue;
+                            }
+                            if (event == null) {
+                                break;
+                            }
+
+                            // For USB, each 32 bit word of a UMP is
+                            // sent with the least significant byte first.
+                            swapEndiannessPerWord(event.data, event.count);
+
+                            if (DEBUG) {
+                                logByteArray("Output ", event.data, 0,
+                                        event.count);
+                            }
+                            connectionF.bulkTransfer(epF, event.data, event.count, 0);
+                            eventSchedulerF.addEventToPool(event);
+                        }
+                        Log.d(TAG, "output thread exit");
+                    }
+                }.start();
+
+                portNumber++;
+            }
+        }
+
+        mIsOpen = true;
+        return true;
+    }
+
+    private boolean register(Context context) {
+        mContext = context;
+        MidiManager midiManager = context.getSystemService(MidiManager.class);
+        if (midiManager == null) {
+            Log.e(TAG, "No MidiManager in UsbUniversalMidiDevice.create()");
+            return false;
+        }
+
+        mDefaultMidiProtocol = calculateDefaultMidiProtocol();
+
+        Bundle properties = new Bundle();
+        String manufacturer = mUsbDevice.getManufacturerName();
+        String product = mUsbDevice.getProductName();
+        String version = mUsbDevice.getVersion();
+        String name;
+        if (manufacturer == null || manufacturer.isEmpty()) {
+            name = product;
+        } else if (product == null || product.isEmpty()) {
+            name = manufacturer;
+        } else {
+            name = manufacturer + " " + product + " MIDI 2.0";
+        }
+        properties.putString(MidiDeviceInfo.PROPERTY_NAME, name);
+        properties.putString(MidiDeviceInfo.PROPERTY_MANUFACTURER, manufacturer);
+        properties.putString(MidiDeviceInfo.PROPERTY_PRODUCT, product);
+        properties.putString(MidiDeviceInfo.PROPERTY_VERSION, version);
+        properties.putString(MidiDeviceInfo.PROPERTY_SERIAL_NUMBER,
+                mUsbDevice.getSerialNumber());
+        properties.putParcelable(MidiDeviceInfo.PROPERTY_USB_DEVICE, mUsbDevice);
+
+        mServer = midiManager.createDeviceServer(mMidiInputPortReceivers, mNumInputs,
+                null, null, properties, MidiDeviceInfo.TYPE_USB, mDefaultMidiProtocol, mCallback);
+        if (mServer == null) {
+            return false;
+        }
+
+        return true;
+    }
+
+    @Override
+    public void close() throws IOException {
+        synchronized (mLock) {
+            if (mIsOpen) {
+                closeLocked();
+            }
+        }
+
+        if (mServer != null) {
+            IoUtils.closeQuietly(mServer);
+        }
+    }
+
+    private void closeLocked() {
+        for (int i = 0; i < mEventSchedulers.length; i++) {
+            mMidiInputPortReceivers[i].setReceiver(null);
+            mEventSchedulers[i].close();
+        }
+        for (UsbDeviceConnection connection : mUsbDeviceConnections) {
+            connection.close();
+        }
+        mUsbDeviceConnections = null;
+        mInputUsbEndpoints = null;
+        mOutputUsbEndpoints = null;
+
+        mIsOpen = false;
+    }
+
+    private void swapEndiannessPerWord(byte[] array, int size) {
+        for (int i = 0; i + 3 < size; i += 4) {
+            byte tmp = array[i];
+            array[i] = array[i + 3];
+            array[i + 3] = tmp;
+            tmp = array[i + 1];
+            array[i + 1] = array[i + 2];
+            array[i + 2] = tmp;
+        }
+    }
+
+    private static void logByteArray(String prefix, byte[] value, int offset, int count) {
+        StringBuilder builder = new StringBuilder(prefix);
+        for (int i = offset; i < offset + count; i++) {
+            builder.append(String.format("0x%02X", value[i]));
+            if (i != value.length - 1) {
+                builder.append(", ");
+            }
+        }
+        Log.d(TAG, builder.toString());
+    }
+}
diff --git a/services/usb/java/com/android/server/usb/descriptors/UsbACAudioControlEndpoint.java b/services/usb/java/com/android/server/usb/descriptors/UsbACAudioControlEndpoint.java
index 409e605c3c2f8..bfcf62147f75c 100644
--- a/services/usb/java/com/android/server/usb/descriptors/UsbACAudioControlEndpoint.java
+++ b/services/usb/java/com/android/server/usb/descriptors/UsbACAudioControlEndpoint.java
@@ -38,8 +38,8 @@ public class UsbACAudioControlEndpoint extends UsbACEndpoint {
     static final byte ATTRIBSMASK_SYNC  = 0x0C;
     static final byte ATTRIBMASK_TRANS  = 0x03;
 
-    public UsbACAudioControlEndpoint(int length, byte type, int subclass) {
-        super(length, type, subclass);
+    public UsbACAudioControlEndpoint(int length, byte type, int subclass, byte subtype) {
+        super(length, type, subclass, subtype);
     }
 
     public byte getAddress() {
diff --git a/services/usb/java/com/android/server/usb/descriptors/UsbACAudioStreamEndpoint.java b/services/usb/java/com/android/server/usb/descriptors/UsbACAudioStreamEndpoint.java
index e63bb74abdf7d..ae9ca0d827f50 100644
--- a/services/usb/java/com/android/server/usb/descriptors/UsbACAudioStreamEndpoint.java
+++ b/services/usb/java/com/android/server/usb/descriptors/UsbACAudioStreamEndpoint.java
@@ -24,8 +24,8 @@ public class UsbACAudioStreamEndpoint extends UsbACEndpoint {
     private static final String TAG = "UsbACAudioStreamEndpoint";
 
     //TODO data fields...
-    public UsbACAudioStreamEndpoint(int length, byte type, int subclass) {
-        super(length, type, subclass);
+    public UsbACAudioStreamEndpoint(int length, byte type, int subclass, byte subtype) {
+        super(length, type, subclass, subtype);
     }
 
     @Override
diff --git a/services/usb/java/com/android/server/usb/descriptors/UsbACEndpoint.java b/services/usb/java/com/android/server/usb/descriptors/UsbACEndpoint.java
index ff7f3934086cf..b7f9ac334954a 100644
--- a/services/usb/java/com/android/server/usb/descriptors/UsbACEndpoint.java
+++ b/services/usb/java/com/android/server/usb/descriptors/UsbACEndpoint.java
@@ -25,13 +25,17 @@ import android.util.Log;
 abstract class UsbACEndpoint extends UsbDescriptor {
     private static final String TAG = "UsbACEndpoint";
 
+    public static final byte MS_GENERAL = 1;
+    public static final byte MS_GENERAL_2_0 = 2;
+
     protected final int mSubclass; // from the mSubclass member of the "enclosing"
                                    // Interface Descriptor, not the stream.
-    protected byte mSubtype;       // 2:1 HEADER descriptor subtype
+    protected final byte mSubtype;       // 2:1 HEADER descriptor subtype
 
-    UsbACEndpoint(int length, byte type, int subclass) {
+    UsbACEndpoint(int length, byte type, int subclass, byte subtype) {
         super(length, type);
         mSubclass = subclass;
+        mSubtype = subtype;
     }
 
     public int getSubclass() {
@@ -44,33 +48,39 @@ abstract class UsbACEndpoint extends UsbDescriptor {
 
     @Override
     public int parseRawDescriptors(ByteStream stream) {
-        mSubtype = stream.getByte();
         return mLength;
     }
 
     public static UsbDescriptor allocDescriptor(UsbDescriptorParser parser,
-                                                int length, byte type) {
+                                                int length, byte type, byte subType) {
         UsbInterfaceDescriptor interfaceDesc = parser.getCurInterface();
         int subClass = interfaceDesc.getUsbSubclass();
-        // TODO shouldn't this switch on subtype?
         switch (subClass) {
             case AUDIO_AUDIOCONTROL:
                 if (UsbDescriptorParser.DEBUG) {
                     Log.d(TAG, "---> AUDIO_AUDIOCONTROL");
                 }
-                return new UsbACAudioControlEndpoint(length, type, subClass);
+                return new UsbACAudioControlEndpoint(length, type, subClass, subType);
 
             case AUDIO_AUDIOSTREAMING:
                 if (UsbDescriptorParser.DEBUG) {
                     Log.d(TAG, "---> AUDIO_AUDIOSTREAMING");
                 }
-                return new UsbACAudioStreamEndpoint(length, type, subClass);
+                return new UsbACAudioStreamEndpoint(length, type, subClass, subType);
 
             case AUDIO_MIDISTREAMING:
                 if (UsbDescriptorParser.DEBUG) {
                     Log.d(TAG, "---> AUDIO_MIDISTREAMING");
                 }
-                return new UsbACMidiEndpoint(length, type, subClass);
+                switch (subType) {
+                    case MS_GENERAL:
+                        return new UsbACMidi10Endpoint(length, type, subClass, subType);
+                    case MS_GENERAL_2_0:
+                        return new UsbACMidi20Endpoint(length, type, subClass, subType);
+                    default:
+                        Log.w(TAG, "Unknown Midi Endpoint id:0x" + Integer.toHexString(subType));
+                        return null;
+                }
 
             default:
                 Log.w(TAG, "Unknown Audio Class Endpoint id:0x" + Integer.toHexString(subClass));
diff --git a/services/usb/java/com/android/server/usb/descriptors/UsbACMidiEndpoint.java b/services/usb/java/com/android/server/usb/descriptors/UsbACMidi10Endpoint.java
similarity index 72%
rename from services/usb/java/com/android/server/usb/descriptors/UsbACMidiEndpoint.java
rename to services/usb/java/com/android/server/usb/descriptors/UsbACMidi10Endpoint.java
index 42ee88922edd7..49b9d7b30d297 100644
--- a/services/usb/java/com/android/server/usb/descriptors/UsbACMidiEndpoint.java
+++ b/services/usb/java/com/android/server/usb/descriptors/UsbACMidi10Endpoint.java
@@ -22,14 +22,14 @@ import com.android.server.usb.descriptors.report.ReportCanvas;
  * An audio class-specific Midi Endpoint.
  * see midi10.pdf section 6.2.2
  */
-public final class UsbACMidiEndpoint extends UsbACEndpoint {
-    private static final String TAG = "UsbACMidiEndpoint";
+public final class UsbACMidi10Endpoint extends UsbACEndpoint {
+    private static final String TAG = "UsbACMidi10Endpoint";
 
     private byte mNumJacks;
-    private byte[] mJackIds;
+    private byte[] mJackIds = new byte[0];
 
-    public UsbACMidiEndpoint(int length, byte type, int subclass) {
-        super(length, type, subclass);
+    public UsbACMidi10Endpoint(int length, byte type, int subclass, byte subtype) {
+        super(length, type, subclass, subtype);
     }
 
     public byte getNumJacks() {
@@ -45,9 +45,11 @@ public final class UsbACMidiEndpoint extends UsbACEndpoint {
         super.parseRawDescriptors(stream);
 
         mNumJacks = stream.getByte();
-        mJackIds = new byte[mNumJacks];
-        for (int jack = 0; jack < mNumJacks; jack++) {
-            mJackIds[jack] = stream.getByte();
+        if (mNumJacks > 0) {
+            mJackIds = new byte[mNumJacks];
+            for (int jack = 0; jack < mNumJacks; jack++) {
+                mJackIds[jack] = stream.getByte();
+            }
         }
         return mLength;
     }
@@ -56,10 +58,10 @@ public final class UsbACMidiEndpoint extends UsbACEndpoint {
     public void report(ReportCanvas canvas) {
         super.report(canvas);
 
-        canvas.writeHeader(3, "AC Midi Endpoint: " + ReportCanvas.getHexString(getType())
+        canvas.writeHeader(3, "ACMidi10Endpoint: " + ReportCanvas.getHexString(getType())
                 + " Length: " + getLength());
         canvas.openList();
         canvas.writeListItem("" + getNumJacks() + " Jacks.");
         canvas.closeList();
     }
-}
\ No newline at end of file
+}
diff --git a/services/usb/java/com/android/server/usb/descriptors/UsbACMidi20Endpoint.java b/services/usb/java/com/android/server/usb/descriptors/UsbACMidi20Endpoint.java
new file mode 100644
index 0000000000000..1024a5bf55a68
--- /dev/null
+++ b/services/usb/java/com/android/server/usb/descriptors/UsbACMidi20Endpoint.java
@@ -0,0 +1,67 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.android.server.usb.descriptors;
+
+import com.android.server.usb.descriptors.report.ReportCanvas;
+
+/**
+ * @hide
+ * An audio class-specific Midi Endpoint.
+ * see midi10.pdf section 6.2.2
+ */
+public final class UsbACMidi20Endpoint extends UsbACEndpoint {
+    private static final String TAG = "UsbACMidi20Endpoint";
+
+    private byte mNumGroupTerminals;
+    private byte[] mBlockIds = new byte[0];
+
+    public UsbACMidi20Endpoint(int length, byte type, int subclass, byte subtype) {
+        super(length, type, subclass, subtype);
+    }
+
+    public byte getNumGroupTerminals() {
+        return mNumGroupTerminals;
+    }
+
+    public byte[] getBlockIds() {
+        return mBlockIds;
+    }
+
+    @Override
+    public int parseRawDescriptors(ByteStream stream) {
+        super.parseRawDescriptors(stream);
+
+        mNumGroupTerminals = stream.getByte();
+        if (mNumGroupTerminals > 0) {
+            mBlockIds = new byte[mNumGroupTerminals];
+            for (int block = 0; block < mNumGroupTerminals; block++) {
+                mBlockIds[block] = stream.getByte();
+            }
+        }
+        return mLength;
+    }
+
+    @Override
+    public void report(ReportCanvas canvas) {
+        super.report(canvas);
+
+        canvas.writeHeader(3, "AC Midi20 Endpoint: " + ReportCanvas.getHexString(getType())
+                + " Length: " + getLength());
+        canvas.openList();
+        canvas.writeListItem("" + getNumGroupTerminals() + " Group Terminals.");
+        canvas.closeList();
+    }
+}
diff --git a/services/usb/java/com/android/server/usb/descriptors/UsbDescriptorParser.java b/services/usb/java/com/android/server/usb/descriptors/UsbDescriptorParser.java
index 7250a071835d8..3412a6f80cc7c 100644
--- a/services/usb/java/com/android/server/usb/descriptors/UsbDescriptorParser.java
+++ b/services/usb/java/com/android/server/usb/descriptors/UsbDescriptorParser.java
@@ -30,6 +30,9 @@ public final class UsbDescriptorParser {
 
     private final String mDeviceAddr;
 
+    private static final int MS_MIDI_1_0 = 0x0100;
+    private static final int MS_MIDI_2_0 = 0x0200;
+
     // Descriptor Objects
     private static final int DESCRIPTORS_ALLOC_SIZE = 128;
     private final ArrayList<UsbDescriptor> mDescriptors;
@@ -215,6 +218,7 @@ public final class UsbDescriptorParser {
                             Log.w(TAG, "  Unparsed Class-specific");
                             break;
                     }
+                    mCurInterfaceDescriptor.setClassSpecificInterfaceDescriptor(descriptor);
                 }
                 break;
 
@@ -222,17 +226,25 @@ public final class UsbDescriptorParser {
                 if (mCurInterfaceDescriptor != null) {
                     int subClass = mCurInterfaceDescriptor.getUsbClass();
                     switch (subClass) {
-                        case UsbDescriptor.CLASSID_AUDIO:
-                            descriptor = UsbACEndpoint.allocDescriptor(this, length, type);
+                        case UsbDescriptor.CLASSID_AUDIO: {
+                            Byte subType = stream.getByte();
+                            if (DEBUG) {
+                                Log.d(TAG, "UsbDescriptor.CLASSID_AUDIO type:0x"
+                                        + Integer.toHexString(type));
+                            }
+                            descriptor = UsbACEndpoint.allocDescriptor(this, length, type,
+                                    subType);
+                        }
                             break;
 
                         case UsbDescriptor.CLASSID_VIDEO: {
-                            Byte subtype = stream.getByte();
+                            Byte subType = stream.getByte();
                             if (DEBUG) {
                                 Log.d(TAG, "UsbDescriptor.CLASSID_VIDEO type:0x"
                                         + Integer.toHexString(type));
                             }
-                            descriptor = UsbVCEndpoint.allocDescriptor(this, length, type, subtype);
+                            descriptor = UsbVCEndpoint.allocDescriptor(this, length, type,
+                                    subType);
                         }
                             break;
 
@@ -644,8 +656,8 @@ public final class UsbDescriptorParser {
         for (UsbDescriptor descriptor : descriptors) {
             // enusure that this isn't an unrecognized interface descriptor
             if (descriptor instanceof UsbInterfaceDescriptor) {
-                UsbInterfaceDescriptor interfaceDescr = (UsbInterfaceDescriptor) descriptor;
-                if (interfaceDescr.getUsbSubclass() == UsbDescriptor.AUDIO_MIDISTREAMING) {
+                UsbInterfaceDescriptor interfaceDescriptor = (UsbInterfaceDescriptor) descriptor;
+                if (interfaceDescriptor.getUsbSubclass() == UsbDescriptor.AUDIO_MIDISTREAMING) {
                     return true;
                 }
             } else {
@@ -656,17 +668,90 @@ public final class UsbDescriptorParser {
         return false;
     }
 
-    private int calculateNumMidiPorts(boolean isOutput) {
+    /**
+     * @hide
+     */
+    public boolean containsUniversalMidiDeviceEndpoint() {
+        ArrayList<UsbInterfaceDescriptor> interfaceDescriptors =
+                findUniversalMidiInterfaceDescriptors();
+        int outputCount = 0;
+        int inputCount = 0;
+        for (int interfaceIndex = 0; interfaceIndex < interfaceDescriptors.size();
+                interfaceIndex++) {
+            UsbInterfaceDescriptor interfaceDescriptor = interfaceDescriptors.get(interfaceIndex);
+            for (int endpointIndex = 0; endpointIndex < interfaceDescriptor.getNumEndpoints();
+                    endpointIndex++) {
+                UsbEndpointDescriptor endpoint =
+                        interfaceDescriptor.getEndpointDescriptor(endpointIndex);
+                // 0 is output, 1 << 7 is input.
+                if (endpoint.getDirection() == 0) {
+                    outputCount++;
+                } else {
+                    inputCount++;
+                }
+            }
+        }
+        return (outputCount > 0) || (inputCount > 0);
+    }
+
+    /**
+     * @hide
+     */
+    public ArrayList<UsbInterfaceDescriptor> findUniversalMidiInterfaceDescriptors() {
+        int count = 0;
+        ArrayList<UsbDescriptor> descriptors =
+                getInterfaceDescriptorsForClass(UsbDescriptor.CLASSID_AUDIO);
+        ArrayList<UsbInterfaceDescriptor> universalMidiInterfaces =
+                new ArrayList<UsbInterfaceDescriptor>();
+
+        for (UsbDescriptor descriptor : descriptors) {
+            // ensure that this isn't an unrecognized interface descriptor
+            if (descriptor instanceof UsbInterfaceDescriptor) {
+                UsbInterfaceDescriptor interfaceDescriptor = (UsbInterfaceDescriptor) descriptor;
+                if (interfaceDescriptor.getUsbSubclass() == UsbDescriptor.AUDIO_MIDISTREAMING) {
+                    UsbDescriptor classSpecificDescriptor =
+                            interfaceDescriptor.getClassSpecificInterfaceDescriptor();
+                    if (classSpecificDescriptor != null) {
+                        if (classSpecificDescriptor instanceof UsbMSMidiHeader) {
+                            UsbMSMidiHeader midiHeader =
+                                    (UsbMSMidiHeader) classSpecificDescriptor;
+                            if (midiHeader.getMidiStreamingClass() == MS_MIDI_2_0) {
+                                universalMidiInterfaces.add(interfaceDescriptor);
+                            }
+                        }
+                    }
+                }
+            } else {
+                Log.w(TAG, "Undefined Audio Class Interface l: " + descriptor.getLength()
+                        + " t:0x" + Integer.toHexString(descriptor.getType()));
+            }
+        }
+        return universalMidiInterfaces;
+    }
+
+    private int calculateNumLegacyMidiPorts(boolean isOutput) {
         int count = 0;
         ArrayList<UsbDescriptor> descriptors =
                 getInterfaceDescriptorsForClass(UsbDescriptor.CLASSID_AUDIO);
         for (UsbDescriptor descriptor : descriptors) {
             // ensure that this isn't an unrecognized interface descriptor
             if (descriptor instanceof UsbInterfaceDescriptor) {
-                UsbInterfaceDescriptor interfaceDescr = (UsbInterfaceDescriptor) descriptor;
-                if (interfaceDescr.getUsbSubclass() == UsbDescriptor.AUDIO_MIDISTREAMING) {
-                    for (int i = 0; i < interfaceDescr.getNumEndpoints(); i++) {
-                        UsbEndpointDescriptor endpoint = interfaceDescr.getEndpointDescriptor(i);
+                UsbInterfaceDescriptor interfaceDescriptor = (UsbInterfaceDescriptor) descriptor;
+                if (interfaceDescriptor.getUsbSubclass() == UsbDescriptor.AUDIO_MIDISTREAMING) {
+                    UsbDescriptor classSpecificDescriptor =
+                            interfaceDescriptor.getClassSpecificInterfaceDescriptor();
+                    if (classSpecificDescriptor != null) {
+                        if (classSpecificDescriptor instanceof UsbMSMidiHeader) {
+                            UsbMSMidiHeader midiHeader =
+                                    (UsbMSMidiHeader) classSpecificDescriptor;
+                            if (midiHeader.getMidiStreamingClass() != MS_MIDI_1_0) {
+                                continue;
+                            }
+                        }
+                    }
+                    for (int i = 0; i < interfaceDescriptor.getNumEndpoints(); i++) {
+                        UsbEndpointDescriptor endpoint =
+                                interfaceDescriptor.getEndpointDescriptor(i);
                         // 0 is output, 1 << 7 is input.
                         if ((endpoint.getDirection() == 0) == isOutput) {
                             count++;
@@ -684,15 +769,15 @@ public final class UsbDescriptorParser {
     /**
      * @hide
      */
-    public int calculateNumMidiInputs() {
-        return calculateNumMidiPorts(false /*isOutput*/);
+    public int calculateNumLegacyMidiInputs() {
+        return calculateNumLegacyMidiPorts(false /*isOutput*/);
     }
 
     /**
      * @hide
      */
-    public int calculateNumMidiOutputs() {
-        return calculateNumMidiPorts(true /*isOutput*/);
+    public int calculateNumLegacyMidiOutputs() {
+        return calculateNumLegacyMidiPorts(true /*isOutput*/);
     }
 
     /**
diff --git a/services/usb/java/com/android/server/usb/descriptors/UsbEndpointDescriptor.java b/services/usb/java/com/android/server/usb/descriptors/UsbEndpointDescriptor.java
index 4d0cfea98630f..ab07ce7fdb7ab 100644
--- a/services/usb/java/com/android/server/usb/descriptors/UsbEndpointDescriptor.java
+++ b/services/usb/java/com/android/server/usb/descriptors/UsbEndpointDescriptor.java
@@ -112,7 +112,10 @@ public class UsbEndpointDescriptor extends UsbDescriptor {
         return mEndpointAddress & UsbEndpointDescriptor.MASK_ENDPOINT_DIRECTION;
     }
 
-    /* package */ UsbEndpoint toAndroid(UsbDescriptorParser parser) {
+    /**
+    * Returns a UsbEndpoint that this UsbEndpointDescriptor is describing.
+    */
+    public UsbEndpoint toAndroid(UsbDescriptorParser parser) {
         if (UsbDescriptorParser.DEBUG) {
             Log.d(TAG, "toAndroid() type:"
                     + Integer.toHexString(mAttributes & MASK_ATTRIBS_TRANSTYPE)
diff --git a/services/usb/java/com/android/server/usb/descriptors/UsbInterfaceDescriptor.java b/services/usb/java/com/android/server/usb/descriptors/UsbInterfaceDescriptor.java
index 64dbd971cc679..ca4613b17873c 100644
--- a/services/usb/java/com/android/server/usb/descriptors/UsbInterfaceDescriptor.java
+++ b/services/usb/java/com/android/server/usb/descriptors/UsbInterfaceDescriptor.java
@@ -42,6 +42,8 @@ public class UsbInterfaceDescriptor extends UsbDescriptor {
     private ArrayList<UsbEndpointDescriptor> mEndpointDescriptors =
             new ArrayList<UsbEndpointDescriptor>();
 
+    private UsbDescriptor mClassSpecificInterfaceDescriptor;
+
     UsbInterfaceDescriptor(int length, byte type) {
         super(length, type);
         mHierarchyLevel = 3;
@@ -105,7 +107,18 @@ public class UsbInterfaceDescriptor extends UsbDescriptor {
         mEndpointDescriptors.add(endpoint);
     }
 
-    UsbInterface toAndroid(UsbDescriptorParser parser) {
+    public void setClassSpecificInterfaceDescriptor(UsbDescriptor descriptor) {
+        mClassSpecificInterfaceDescriptor = descriptor;
+    }
+
+    public UsbDescriptor getClassSpecificInterfaceDescriptor() {
+        return mClassSpecificInterfaceDescriptor;
+    }
+
+    /**
+    * Returns a UsbInterface that this UsbInterfaceDescriptor is describing.
+    */
+    public UsbInterface toAndroid(UsbDescriptorParser parser) {
         if (UsbDescriptorParser.DEBUG) {
             Log.d(TAG, "toAndroid() class:" + Integer.toHexString(mUsbClass)
                     + " subclass:" + Integer.toHexString(mUsbSubclass)
diff --git a/services/usb/java/com/android/server/usb/descriptors/UsbMSMidiHeader.java b/services/usb/java/com/android/server/usb/descriptors/UsbMSMidiHeader.java
index d0ca6db87d382..76535612f54d7 100644
--- a/services/usb/java/com/android/server/usb/descriptors/UsbMSMidiHeader.java
+++ b/services/usb/java/com/android/server/usb/descriptors/UsbMSMidiHeader.java
@@ -25,13 +25,19 @@ import com.android.server.usb.descriptors.report.ReportCanvas;
 public final class UsbMSMidiHeader extends UsbACInterface {
     private static final String TAG = "UsbMSMidiHeader";
 
+    private int mMidiStreamingClass;  // MSC Specification Release (BCD).
+
     public UsbMSMidiHeader(int length, byte type, byte subtype, int subclass) {
         super(length, type, subtype, subclass);
     }
 
+    public int getMidiStreamingClass() {
+        return mMidiStreamingClass;
+    }
+
     @Override
     public int parseRawDescriptors(ByteStream stream) {
-        // TODO - read data memebers
+        mMidiStreamingClass = stream.unpackUsbShort();
         stream.advance(mLength - stream.getReadCount());
         return mLength;
     }
@@ -42,6 +48,7 @@ public final class UsbMSMidiHeader extends UsbACInterface {
 
         canvas.writeHeader(3, "MS Midi Header: " + ReportCanvas.getHexString(getType())
                 + " SubType: " + ReportCanvas.getHexString(getSubclass())
-                + " Length: " + getLength());
+                + " Length: " + getLength()
+                + " MidiStreamingClass :" + getMidiStreamingClass());
     }
 }
diff --git a/services/usb/java/com/android/server/usb/descriptors/UsbMidiBlockParser.java b/services/usb/java/com/android/server/usb/descriptors/UsbMidiBlockParser.java
new file mode 100644
index 0000000000000..37bd0f8f6f7b3
--- /dev/null
+++ b/services/usb/java/com/android/server/usb/descriptors/UsbMidiBlockParser.java
@@ -0,0 +1,173 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.android.server.usb.descriptors;
+
+import android.hardware.usb.UsbConstants;
+import android.hardware.usb.UsbDeviceConnection;
+import android.util.Log;
+
+import java.util.ArrayList;
+
+/**
+ * @hide
+ * A class to parse Block Descriptors
+ * see midi20.pdf section 5.4
+ */
+public class UsbMidiBlockParser {
+    private static final String TAG = "UsbMidiBlockParser";
+
+    // Block header size
+    public static final int MIDI_BLOCK_HEADER_SIZE = 5;
+    public static final int MIDI_BLOCK_SIZE = 13;
+    public static final int REQ_GET_DESCRIPTOR = 0x06;
+    public static final int CS_GR_TRM_BLOCK = 0x26;     // Class-specific GR_TRM_BLK
+    public static final int GR_TRM_BLOCK_HEADER = 0x01; // Group block header
+    public static final int REQ_TIMEOUT_MS = 2000;      // 2 second timeout
+    public static final int DEFAULT_MIDI_TYPE = 1;      // Default MIDI type
+
+    protected int mHeaderLength;            // 0:1 Size of header descriptor
+    protected int mHeaderDescriptorType;    // 1:1 Descriptor Type
+    protected int mHeaderDescriptorSubtype; // 2:1 Descriptor Subtype
+    protected int mTotalLength;             // 3:2 Total Length of header and blocks
+
+    static class GroupTerminalBlock {
+        protected int mLength;                  // 0:1 Size of descriptor
+        protected int mDescriptorType;          // 1:1 Descriptor Type
+        protected int mDescriptorSubtype;       // 2:1 Descriptor Subtype
+        protected int mGroupBlockId;            // 3:1 Id of Group Terminal Block
+        protected int mGroupTerminalBlockType;  // 4:1 bi-directional, IN, or OUT
+        protected int mGroupTerminal;           // 5:1 Group Terminal Number
+        protected int mNumGroupTerminals;       // 6:1 Number of Group Terminals
+        protected int mBlockItem;               // 7:1 ID of STRING descriptor of Block item
+        protected int mMidiProtocol;            // 8:1 MIDI protocol
+        protected int mMaxInputBandwidth;       // 9:2 Max Input Bandwidth
+        protected int mMaxOutputBandwidth;      // 11:2 Max Output Bandwidth
+
+        public int parseRawDescriptors(ByteStream stream) {
+            mLength = stream.getUnsignedByte();
+            mDescriptorType = stream.getUnsignedByte();
+            mDescriptorSubtype = stream.getUnsignedByte();
+            mGroupBlockId = stream.getUnsignedByte();
+            mGroupTerminalBlockType = stream.getUnsignedByte();
+            mGroupTerminal = stream.getUnsignedByte();
+            mNumGroupTerminals = stream.getUnsignedByte();
+            mBlockItem = stream.getUnsignedByte();
+            mMidiProtocol = stream.getUnsignedByte();
+            mMaxInputBandwidth = stream.unpackUsbShort();
+            mMaxOutputBandwidth = stream.unpackUsbShort();
+            return mLength;
+        }
+    }
+
+    private ArrayList<GroupTerminalBlock> mGroupTerminalBlocks =
+            new ArrayList<GroupTerminalBlock>();
+
+    public UsbMidiBlockParser() {
+    }
+
+    /**
+     * Parses a raw ByteStream into a block terminal descriptor.
+     * The header is parsed before each block is parsed.
+     * @param   stream  ByteStream to parse
+     * @return          The total length that has been parsed.
+     */
+    public int parseRawDescriptors(ByteStream stream) {
+        mHeaderLength = stream.getUnsignedByte();
+        mHeaderDescriptorType = stream.getUnsignedByte();
+        mHeaderDescriptorSubtype = stream.getUnsignedByte();
+        mTotalLength = stream.unpackUsbShort();
+
+        while (stream.available() >= MIDI_BLOCK_SIZE) {
+            GroupTerminalBlock block = new GroupTerminalBlock();
+            block.parseRawDescriptors(stream);
+            mGroupTerminalBlocks.add(block);
+        }
+
+        return mTotalLength;
+    }
+
+    /**
+     * Calculates the MIDI type through querying the device twice, once for the size
+     * of the block descriptor and once for the block descriptor. This descriptor is
+     * then parsed to return the MIDI type.
+     * See the MIDI 2.0 USB doc for more info.
+     * @param  connection               UsbDeviceConnection to send the request
+     * @param  interfaceNumber          The interface number to query
+     * @param  alternateInterfaceNumber The alternate interface of the interface
+     * @return                          The MIDI type as an int.
+     */
+    public int calculateMidiType(UsbDeviceConnection connection, int interfaceNumber,
+            int alternateInterfaceNumber) {
+        byte[] byteArray = new byte[MIDI_BLOCK_HEADER_SIZE];
+        try {
+            // This first request is simply to get the full size of the descriptor.
+            // This info is stored in the last two bytes of the header.
+            int rdo = connection.controlTransfer(
+                    UsbConstants.USB_DIR_IN | UsbConstants.USB_TYPE_STANDARD
+                            | UsbConstants.USB_CLASS_AUDIO,
+                    REQ_GET_DESCRIPTOR,
+                    (CS_GR_TRM_BLOCK << 8) + alternateInterfaceNumber,
+                    interfaceNumber,
+                    byteArray,
+                    MIDI_BLOCK_HEADER_SIZE,
+                    REQ_TIMEOUT_MS);
+            if (rdo > 0) {
+                if (byteArray[1] != CS_GR_TRM_BLOCK) {
+                    Log.e(TAG, "Incorrect descriptor type: " + byteArray[1]);
+                    return DEFAULT_MIDI_TYPE;
+                }
+                if (byteArray[2] != GR_TRM_BLOCK_HEADER) {
+                    Log.e(TAG, "Incorrect descriptor subtype: " + byteArray[2]);
+                    return DEFAULT_MIDI_TYPE;
+                }
+                int newSize = (((int) byteArray[3]) & (0xff))
+                        + ((((int) byteArray[4]) & (0xff)) << 8);
+                if (newSize <= 0) {
+                    Log.e(TAG, "Parsed a non-positive block terminal size: " + newSize);
+                    return DEFAULT_MIDI_TYPE;
+                }
+                byteArray = new byte[newSize];
+                rdo = connection.controlTransfer(
+                        UsbConstants.USB_DIR_IN | UsbConstants.USB_TYPE_STANDARD
+                                | UsbConstants.USB_CLASS_AUDIO,
+                        REQ_GET_DESCRIPTOR,
+                        (CS_GR_TRM_BLOCK << 8) + alternateInterfaceNumber,
+                        interfaceNumber,
+                        byteArray,
+                        newSize,
+                        REQ_TIMEOUT_MS);
+                if (rdo > 0) {
+                    ByteStream stream = new ByteStream(byteArray);
+                    parseRawDescriptors(stream);
+                    if (mGroupTerminalBlocks.isEmpty()) {
+                        Log.e(TAG, "Group Terminal Blocks failed parsing: " + DEFAULT_MIDI_TYPE);
+                        return DEFAULT_MIDI_TYPE;
+                    } else {
+                        Log.d(TAG, "MIDI protocol: " + mGroupTerminalBlocks.get(0).mMidiProtocol);
+                        return mGroupTerminalBlocks.get(0).mMidiProtocol;
+                    }
+                } else {
+                    Log.e(TAG, "second transfer failed: " + rdo);
+                }
+            } else {
+                Log.e(TAG, "first transfer failed: " + rdo);
+            }
+        } catch (Exception e) {
+            Log.e(TAG, "Can not communicate with USB device", e);
+        }
+        return DEFAULT_MIDI_TYPE;
+    }
+}