diff --git a/dom/midi/MIDITypes.ipdlh b/dom/midi/MIDITypes.ipdlh
new file mode 100644
index 000000000000..004480e42bbe
--- /dev/null
+++ b/dom/midi/MIDITypes.ipdlh
@@ -0,0 +1,31 @@
+/* -*- Mode: C++; c-basic-offset: 4; indent-tabs-mode: nil; tab-width: 8 -*- */
+/* vim: set sw=4 ts=8 et tw=80 ft=cpp : */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+using mozilla::TimeStamp from "mozilla/TimeStamp.h";
+
+namespace mozilla {
+namespace dom {
+
+struct MIDIPortInfo {
+    nsString id;
+    nsString name;
+    nsString manufacturer;
+    nsString version;
+    //Actually a MIDIPortType enum
+    uint32_t type;
+};
+
+struct MIDIMessage {
+    uint8_t[] data;
+    TimeStamp timestamp;
+};
+
+struct MIDIPortList {
+    MIDIPortInfo[] ports;
+};
+
+} // namespace dom
+} // namespace mozilla
diff --git a/dom/midi/PMIDIManager.ipdl b/dom/midi/PMIDIManager.ipdl
new file mode 100644
index 000000000000..eb5f363fd444
--- /dev/null
+++ b/dom/midi/PMIDIManager.ipdl
@@ -0,0 +1,25 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+include protocol PBackground;
+include MIDITypes;
+
+namespace mozilla {
+namespace dom {
+
+async protocol PMIDIManager
+{
+  manager PBackground;
+parent:
+  async Shutdown();
+child:
+  /*
+   * Send an updated list of MIDI ports to the child
+   */
+  async MIDIPortListUpdate(MIDIPortList aPortList);
+  async __delete__();
+};
+
+} // namespace ipc
+} // namespace mozilla
diff --git a/dom/midi/PMIDIPort.ipdl b/dom/midi/PMIDIPort.ipdl
new file mode 100644
index 000000000000..ebdb9c644d5c
--- /dev/null
+++ b/dom/midi/PMIDIPort.ipdl
@@ -0,0 +1,31 @@
+/* -*- Mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; tab-width: 40 -*- */
+/* vim: set ts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+include protocol PBackground;
+include MIDITypes;
+
+namespace mozilla {
+namespace dom {
+
+async protocol PMIDIPort
+{
+  manager PBackground;
+parent:
+  async Shutdown();
+  async Send(MIDIMessage[] msg);
+  async Open();
+  async Close();
+  async Clear();
+child:
+  async Receive(MIDIMessage[] msg);
+  // Actually takes a MIDIDeviceConnectionState and MIDIPortConnectionState
+  // respectively.
+  async UpdateStatus(uint32_t deviceState, uint32_t connectionState);
+  async __delete__();
+};
+
+}
+}
diff --git a/dom/midi/moz.build b/dom/midi/moz.build
new file mode 100644
index 000000000000..123ebd47f5d8
--- /dev/null
+++ b/dom/midi/moz.build
@@ -0,0 +1,11 @@
+# -*- Mode: python; c-basic-offset: 4; indent-tabs-mode: nil; tab-width: 40 -*-
+# vim: set filetype=python:
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+IPDL_SOURCES += [
+    'MIDITypes.ipdlh',
+    'PMIDIManager.ipdl',
+    'PMIDIPort.ipdl',
+]
diff --git a/ipc/glue/PBackground.ipdl b/ipc/glue/PBackground.ipdl
index 0e29c883cb4d..f3f1164bdc90 100644
--- a/ipc/glue/PBackground.ipdl
+++ b/ipc/glue/PBackground.ipdl
@@ -22,6 +22,8 @@ include protocol PPendingIPCBlob;
 include protocol PTemporaryIPCBlob;
 include protocol PMessagePort;
 include protocol PCameras;
+include protocol PMIDIManager;
+include protocol PMIDIPort;
 include protocol PQuota;
 include protocol PChildToParentStream;
 include protocol PParentToChildStream;
@@ -36,6 +38,7 @@ include PBackgroundSharedTypes;
 include PBackgroundIDBSharedTypes;
 include PFileSystemParams;
 include ProtocolTypes;
+include MIDITypes;
 
 include "mozilla/dom/cache/IPCUtils.h";
 
@@ -73,6 +76,8 @@ sync protocol PBackground
   manages PTemporaryIPCBlob;
   manages PMessagePort;
   manages PCameras;
+  manages PMIDIManager;
+  manages PMIDIPort;
   manages PQuota;
   manages PChildToParentStream;
   manages PParentToChildStream;
@@ -140,6 +145,9 @@ parent:
 
   async PClientManager();
 
+  async PMIDIManager();
+  async PMIDIPort(MIDIPortInfo portInfo, bool sysexEnabled);
+
 child:
   async PCache();
   async PCacheStreamControl();