diff --git a/audio/aidl/Android.bp b/audio/aidl/Android.bp
index 151da49..4fac2ef 100644
--- a/audio/aidl/Android.bp
+++ b/audio/aidl/Android.bp
@@ -75,10 +75,14 @@
         "android/hardware/audio/core/IModule.aidl",
         "android/hardware/audio/core/IStreamIn.aidl",
         "android/hardware/audio/core/IStreamOut.aidl",
+        "android/hardware/audio/core/MmapBufferDescriptor.aidl",
         "android/hardware/audio/core/ModuleDebug.aidl",
+        "android/hardware/audio/core/StreamDescriptor.aidl",
     ],
     imports: [
         "android.hardware.audio.common-V1",
+        "android.hardware.common-V2",
+        "android.hardware.common.fmq-V1",
         "android.media.audio.common.types-V1",
     ],
     stability: "vintf",
diff --git a/audio/aidl/aidl_api/android.hardware.audio.core/current/android/hardware/audio/core/AudioPatch.aidl b/audio/aidl/aidl_api/android.hardware.audio.core/current/android/hardware/audio/core/AudioPatch.aidl
index 1cef4cd..078b5ea 100644
--- a/audio/aidl/aidl_api/android.hardware.audio.core/current/android/hardware/audio/core/AudioPatch.aidl
+++ b/audio/aidl/aidl_api/android.hardware.audio.core/current/android/hardware/audio/core/AudioPatch.aidl
@@ -37,4 +37,6 @@
   int id;
   int[] sourcePortConfigIds;
   int[] sinkPortConfigIds;
+  int minimumStreamBufferSizeFrames;
+  int[] latenciesMs;
 }
diff --git a/audio/aidl/aidl_api/android.hardware.audio.core/current/android/hardware/audio/core/IModule.aidl b/audio/aidl/aidl_api/android.hardware.audio.core/current/android/hardware/audio/core/IModule.aidl
index f8bc2c7..a8bbb15 100644
--- a/audio/aidl/aidl_api/android.hardware.audio.core/current/android/hardware/audio/core/IModule.aidl
+++ b/audio/aidl/aidl_api/android.hardware.audio.core/current/android/hardware/audio/core/IModule.aidl
@@ -43,10 +43,33 @@
   android.media.audio.common.AudioPort[] getAudioPorts();
   android.hardware.audio.core.AudioRoute[] getAudioRoutes();
   android.hardware.audio.core.AudioRoute[] getAudioRoutesForAudioPort(int portId);
-  android.hardware.audio.core.IStreamIn openInputStream(int portConfigId, in android.hardware.audio.common.SinkMetadata sinkMetadata);
-  android.hardware.audio.core.IStreamOut openOutputStream(int portConfigId, in android.hardware.audio.common.SourceMetadata sourceMetadata, in @nullable android.media.audio.common.AudioOffloadInfo offloadInfo);
+  android.hardware.audio.core.IModule.OpenInputStreamReturn openInputStream(in android.hardware.audio.core.IModule.OpenInputStreamArguments args);
+  android.hardware.audio.core.IModule.OpenOutputStreamReturn openOutputStream(in android.hardware.audio.core.IModule.OpenOutputStreamArguments args);
   android.hardware.audio.core.AudioPatch setAudioPatch(in android.hardware.audio.core.AudioPatch requested);
   boolean setAudioPortConfig(in android.media.audio.common.AudioPortConfig requested, out android.media.audio.common.AudioPortConfig suggested);
   void resetAudioPatch(int patchId);
   void resetAudioPortConfig(int portConfigId);
+  @VintfStability
+  parcelable OpenInputStreamArguments {
+    int portConfigId;
+    android.hardware.audio.common.SinkMetadata sinkMetadata;
+    long bufferSizeFrames;
+  }
+  @VintfStability
+  parcelable OpenInputStreamReturn {
+    android.hardware.audio.core.IStreamIn stream;
+    android.hardware.audio.core.StreamDescriptor desc;
+  }
+  @VintfStability
+  parcelable OpenOutputStreamArguments {
+    int portConfigId;
+    android.hardware.audio.common.SourceMetadata sourceMetadata;
+    @nullable android.media.audio.common.AudioOffloadInfo offloadInfo;
+    long bufferSizeFrames;
+  }
+  @VintfStability
+  parcelable OpenOutputStreamReturn {
+    android.hardware.audio.core.IStreamOut stream;
+    android.hardware.audio.core.StreamDescriptor desc;
+  }
 }
diff --git a/audio/aidl/aidl_api/android.hardware.audio.core/current/android/hardware/audio/core/MmapBufferDescriptor.aidl b/audio/aidl/aidl_api/android.hardware.audio.core/current/android/hardware/audio/core/MmapBufferDescriptor.aidl
new file mode 100644
index 0000000..6ea1c69
--- /dev/null
+++ b/audio/aidl/aidl_api/android.hardware.audio.core/current/android/hardware/audio/core/MmapBufferDescriptor.aidl
@@ -0,0 +1,41 @@
+/*
+ * Copyright (C) 2022 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.
+ */
+///////////////////////////////////////////////////////////////////////////////
+// THIS FILE IS IMMUTABLE. DO NOT EDIT IN ANY CASE.                          //
+///////////////////////////////////////////////////////////////////////////////
+
+// This file is a snapshot of an AIDL file. Do not edit it manually. There are
+// two cases:
+// 1). this is a frozen version file - do not edit this in any case.
+// 2). this is a 'current' file. If you make a backwards compatible change to
+//     the interface (from the latest frozen version), the build system will
+//     prompt you to update this file with `m <name>-update-api`.
+//
+// You must not make a backward incompatible change to any AIDL file built
+// with the aidl_interface module type with versions property set. The module
+// type is used to build AIDL files in a way that they can be used across
+// independently updatable components of the system. If a device is shipped
+// with such a backward incompatible change, it has a high risk of breaking
+// later when a module using the interface is updated, e.g., Mainline modules.
+
+package android.hardware.audio.core;
+@JavaDerive(equals=true, toString=true) @VintfStability
+parcelable MmapBufferDescriptor {
+  android.hardware.common.Ashmem sharedMemory;
+  long burstSizeFrames;
+  int flags;
+  const int FLAG_INDEX_APPLICATION_SHAREABLE = 0;
+}
diff --git a/audio/aidl/aidl_api/android.hardware.audio.core/current/android/hardware/audio/core/StreamDescriptor.aidl b/audio/aidl/aidl_api/android.hardware.audio.core/current/android/hardware/audio/core/StreamDescriptor.aidl
new file mode 100644
index 0000000..472a8a2
--- /dev/null
+++ b/audio/aidl/aidl_api/android.hardware.audio.core/current/android/hardware/audio/core/StreamDescriptor.aidl
@@ -0,0 +1,69 @@
+/*
+ * Copyright (C) 2022 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.
+ */
+///////////////////////////////////////////////////////////////////////////////
+// THIS FILE IS IMMUTABLE. DO NOT EDIT IN ANY CASE.                          //
+///////////////////////////////////////////////////////////////////////////////
+
+// This file is a snapshot of an AIDL file. Do not edit it manually. There are
+// two cases:
+// 1). this is a frozen version file - do not edit this in any case.
+// 2). this is a 'current' file. If you make a backwards compatible change to
+//     the interface (from the latest frozen version), the build system will
+//     prompt you to update this file with `m <name>-update-api`.
+//
+// You must not make a backward incompatible change to any AIDL file built
+// with the aidl_interface module type with versions property set. The module
+// type is used to build AIDL files in a way that they can be used across
+// independently updatable components of the system. If a device is shipped
+// with such a backward incompatible change, it has a high risk of breaking
+// later when a module using the interface is updated, e.g., Mainline modules.
+
+package android.hardware.audio.core;
+@JavaDerive(equals=true, toString=true) @VintfStability
+parcelable StreamDescriptor {
+  android.hardware.common.fmq.MQDescriptor<android.hardware.audio.core.StreamDescriptor.Command,android.hardware.common.fmq.SynchronizedReadWrite> command;
+  android.hardware.common.fmq.MQDescriptor<android.hardware.audio.core.StreamDescriptor.Reply,android.hardware.common.fmq.SynchronizedReadWrite> reply;
+  long bufferSizeFrames;
+  android.hardware.audio.core.StreamDescriptor.AudioBuffer audio;
+  const int COMMAND_EXIT = 0;
+  const int COMMAND_BURST = 1;
+  const int STATUS_OK = 0;
+  const int STATUS_ILLEGAL_ARGUMENT = 1;
+  const int STATUS_ILLEGAL_STATE = 2;
+  @FixedSize @VintfStability
+  parcelable Position {
+    long frames;
+    long timeNs;
+  }
+  @FixedSize @VintfStability
+  parcelable Command {
+    int code;
+    int fmqByteCount;
+  }
+  @FixedSize @VintfStability
+  parcelable Reply {
+    int status;
+    int fmqByteCount;
+    android.hardware.audio.core.StreamDescriptor.Position observable;
+    android.hardware.audio.core.StreamDescriptor.Position hardware;
+    int latencyMs;
+  }
+  @VintfStability
+  union AudioBuffer {
+    android.hardware.common.fmq.MQDescriptor<byte,android.hardware.common.fmq.UnsynchronizedWrite> fmq;
+    android.hardware.audio.core.MmapBufferDescriptor mmap;
+  }
+}
diff --git a/audio/aidl/android/hardware/audio/core/AudioPatch.aidl b/audio/aidl/android/hardware/audio/core/AudioPatch.aidl
index 48ca214..005d4c0 100644
--- a/audio/aidl/android/hardware/audio/core/AudioPatch.aidl
+++ b/audio/aidl/android/hardware/audio/core/AudioPatch.aidl
@@ -37,4 +37,18 @@
      * unique.
      */
     int[] sinkPortConfigIds;
+    /**
+     * The minimum buffer size, in frames, which streams must use for
+     * this connection configuration. This field is filled out by the
+     * HAL module on creation of the patch and must be a positive number.
+     */
+    int minimumStreamBufferSizeFrames;
+    /**
+     * Latencies, in milliseconds, associated with each sink port config from
+     * the 'sinkPortConfigIds' field. This field is filled out by the HAL module
+     * on creation or updating of the patch and must be a positive number. This
+     * is a nominal value. The current value of latency is provided via
+     * 'StreamDescriptor' command exchange on each audio I/O operation.
+     */
+    int[] latenciesMs;
 }
diff --git a/audio/aidl/android/hardware/audio/core/IModule.aidl b/audio/aidl/android/hardware/audio/core/IModule.aidl
index 802cb2f..363eb68 100644
--- a/audio/aidl/android/hardware/audio/core/IModule.aidl
+++ b/audio/aidl/android/hardware/audio/core/IModule.aidl
@@ -23,6 +23,7 @@
 import android.hardware.audio.core.IStreamIn;
 import android.hardware.audio.core.IStreamOut;
 import android.hardware.audio.core.ModuleDebug;
+import android.hardware.audio.core.StreamDescriptor;
 import android.media.audio.common.AudioOffloadInfo;
 import android.media.audio.common.AudioPort;
 import android.media.audio.common.AudioPortConfig;
@@ -241,22 +242,49 @@
      * 'setAudioPortConfig' method. Existence of an audio patch involving this
      * port configuration is not required for successful opening of a stream.
      *
+     * The requested buffer size is expressed in frames, thus the actual size
+     * in bytes depends on the audio port configuration. Also, the HAL module
+     * may end up providing a larger buffer, thus the requested size is treated
+     * as the minimum size that the client needs. The minimum buffer size
+     * suggested by the HAL is in the 'AudioPatch.minimumStreamBufferSizeFrames'
+     * field, returned as a result of calling the 'setAudioPatch' method.
+     *
      * Only one stream is allowed per audio port configuration. HAL module can
      * also set a limit on how many output streams can be opened for a particular
      * mix port by using its 'AudioPortMixExt.maxOpenStreamCount' field.
      *
-     * @return An opened input stream.
-     * @param portConfigId The ID of the audio mix port config.
-     * @param sinkMetadata Description of the audio that will be recorded.
+     * Note that although it's not prohibited to open a stream on a mix port
+     * configuration which is not connected (using a patch) to any device port,
+     * and set up a patch afterwards, this is not the recommended sequence of
+     * calls, because setting up of a patch might fail due to an insufficient
+     * stream buffer size.
+     *
+     * @return An opened input stream and the associated descriptor.
+     * @param args Input arguments, see 'OpenInputStreamArguments' parcelable.
      * @throws EX_ILLEGAL_ARGUMENT In the following cases:
      *                             - If the port config can not be found by the ID.
      *                             - If the port config is not of an input mix port.
+     *                             - If a buffer of the requested size can not be provided.
      * @throws EX_ILLEGAL_STATE In the following cases:
      *                          - If the port config already has a stream opened on it.
      *                          - If the limit on the open stream count for the port has
      *                            been reached.
      */
-    IStreamIn openInputStream(int portConfigId, in SinkMetadata sinkMetadata);
+    @VintfStability
+    parcelable OpenInputStreamArguments {
+        /** The ID of the audio mix port config. */
+        int portConfigId;
+        /** Description of the audio that will be recorded. */
+        SinkMetadata sinkMetadata;
+        /** Requested audio I/O buffer minimum size, in frames. */
+        long bufferSizeFrames;
+    }
+    @VintfStability
+    parcelable OpenInputStreamReturn {
+        IStreamIn stream;
+        StreamDescriptor desc;
+    }
+    OpenInputStreamReturn openInputStream(in OpenInputStreamArguments args);
 
     /**
      * Open an output stream using an existing audio mix port configuration.
@@ -269,21 +297,33 @@
      * the framework must provide additional information about the encoded
      * audio stream in 'offloadInfo' argument.
      *
+     * The requested buffer size is expressed in frames, thus the actual size
+     * in bytes depends on the audio port configuration. Also, the HAL module
+     * may end up providing a larger buffer, thus the requested size is treated
+     * as the minimum size that the client needs. The minimum buffer size
+     * suggested by the HAL is in the 'AudioPatch.minimumStreamBufferSizeFrames'
+     * field, returned as a result of calling the 'setAudioPatch' method.
+     *
      * Only one stream is allowed per audio port configuration. HAL module can
      * also set a limit on how many output streams can be opened for a particular
      * mix port by using its 'AudioPortMixExt.maxOpenStreamCount' field.
      * Only one stream can be opened on the audio port with 'PRIMARY' output
      * flag. This rule can not be overridden with 'maxOpenStreamCount' field.
      *
-     * @return An opened output stream.
-     * @param portConfigId The ID of the audio mix port config.
-     * @param sourceMetadata Description of the audio that will be played.
-     * @param offloadInfo Additional information for offloaded playback.
+     * Note that although it's not prohibited to open a stream on a mix port
+     * configuration which is not connected (using a patch) to any device port,
+     * and set up a patch afterwards, this is not the recommended sequence of
+     * calls, because setting up of a patch might fail due to an insufficient
+     * stream buffer size.
+     *
+     * @return An opened output stream and the associated descriptor.
+     * @param args Input arguments, see 'OpenOutputStreamArguments' parcelable.
      * @throws EX_ILLEGAL_ARGUMENT In the following cases:
      *                             - If the port config can not be found by the ID.
      *                             - If the port config is not of an output mix port.
      *                             - If the offload info is not provided for an offload
      *                               port configuration.
+     *                             - If a buffer of the requested size can not be provided.
      * @throws EX_ILLEGAL_STATE In the following cases:
      *                          - If the port config already has a stream opened on it.
      *                          - If the limit on the open stream count for the port has
@@ -291,8 +331,23 @@
      *                          - If another opened stream already exists for the 'PRIMARY'
      *                            output port.
      */
-    IStreamOut openOutputStream(int portConfigId, in SourceMetadata sourceMetadata,
-            in @nullable AudioOffloadInfo offloadInfo);
+    @VintfStability
+    parcelable OpenOutputStreamArguments {
+        /** The ID of the audio mix port config. */
+        int portConfigId;
+        /** Description of the audio that will be played. */
+        SourceMetadata sourceMetadata;
+        /** Additional information used for offloaded playback only. */
+        @nullable AudioOffloadInfo offloadInfo;
+        /** Requested audio I/O buffer minimum size, in frames. */
+        long bufferSizeFrames;
+    }
+    @VintfStability
+    parcelable OpenOutputStreamReturn {
+        IStreamOut stream;
+        StreamDescriptor desc;
+    }
+    OpenOutputStreamReturn openOutputStream(in OpenOutputStreamArguments args);
 
     /**
      * Set an audio patch.
@@ -300,19 +355,27 @@
      * This method creates new or updates an existing audio patch. If the
      * requested audio patch does not have a specified id, then a new patch is
      * created and an ID is allocated for it by the HAL module. Otherwise an
-     * attempt to update an existing patch is made. It is recommended that
-     * updating of an existing audio patch should be performed by the HAL module
-     * in a way that does not interrupt active audio streams involving audio
-     * port configurations of the patch. If the HAL module is unable to avoid
-     * interruption when updating a certain patch, it is permitted to allocate a
-     * new patch ID for the result. The returned audio patch contains all the
-     * information about the new or updated audio patch.
+     * attempt to update an existing patch is made.
+     *
+     * The operation of updating an existing audio patch must not change
+     * playback state of audio streams opened on the audio port configurations
+     * of the patch. That is, the HAL module must still be able to consume or
+     * to provide data from / to streams continuously during the patch
+     * switching. Natural intermittent audible loss of some audio frames due to
+     * switching between device ports which does not affect stream playback is
+     * allowed. If the HAL module is unable to avoid playback or recording
+     * state change when updating a certain patch, it must return an error. In
+     * that case, the client must take care of changing port configurations,
+     * patches, and recreating streams in a way which provides an acceptable
+     * user experience.
      *
      * Audio port configurations specified in the patch must be obtained by
      * calling 'setAudioPortConfig' method. There must be an audio route which
      * allows connection between the audio ports whose configurations are used.
-     * An audio patch may be created before or after an audio steam is created
-     * for this configuration.
+     *
+     * When updating an existing audio patch, nominal latency values may change
+     * and must be provided by the HAL module in the returned 'AudioPatch'
+     * structure.
      *
      * @return Resulting audio patch.
      * @param requested Requested audio patch.
@@ -324,6 +387,9 @@
      * @throws EX_ILLEGAL_STATE In the following cases:
      *                          - If application of the patch can only use a route with an
      *                            exclusive use the sink port, and it is already patched.
+     *                          - If updating an existing patch will cause interruption
+     *                            of audio, or requires re-opening of streams due to
+     *                            change of minimum audio I/O buffer size.
      * @throws EX_UNSUPPORTED_OPERATION If the patch can not be established because
      *                                  the HAL module does not support this otherwise valid
      *                                  patch configuration. For example, if it's a patch
diff --git a/audio/aidl/android/hardware/audio/core/IStreamIn.aidl b/audio/aidl/android/hardware/audio/core/IStreamIn.aidl
index b770449..7205bb8 100644
--- a/audio/aidl/android/hardware/audio/core/IStreamIn.aidl
+++ b/audio/aidl/android/hardware/audio/core/IStreamIn.aidl
@@ -28,7 +28,9 @@
      *
      * Releases any resources allocated for this stream on the HAL module side.
      * The stream can not be operated after it has been closed. Methods of this
-     * interface throw EX_ILLEGAL_STATE in for a closed stream.
+     * interface throw EX_ILLEGAL_STATE for a closed stream.
+     *
+     * The associated stream descriptor can be released once this method returns.
      *
      * @throws EX_ILLEGAL_STATE If the stream has already been closed.
      */
diff --git a/audio/aidl/android/hardware/audio/core/IStreamOut.aidl b/audio/aidl/android/hardware/audio/core/IStreamOut.aidl
index 60212fc..0a5aacd 100644
--- a/audio/aidl/android/hardware/audio/core/IStreamOut.aidl
+++ b/audio/aidl/android/hardware/audio/core/IStreamOut.aidl
@@ -28,7 +28,9 @@
      *
      * Releases any resources allocated for this stream on the HAL module side.
      * The stream can not be operated after it has been closed. Methods of this
-     * interface throw EX_ILLEGAL_STATE in for a closed stream.
+     * interface throw EX_ILLEGAL_STATE for a closed stream.
+     *
+     * The associated stream descriptor can be released once this method returns.
      *
      * @throws EX_ILLEGAL_STATE If the stream has already been closed.
      */
diff --git a/audio/aidl/android/hardware/audio/core/MmapBufferDescriptor.aidl b/audio/aidl/android/hardware/audio/core/MmapBufferDescriptor.aidl
new file mode 100644
index 0000000..108bcbe
--- /dev/null
+++ b/audio/aidl/android/hardware/audio/core/MmapBufferDescriptor.aidl
@@ -0,0 +1,51 @@
+/*
+ * Copyright (C) 2022 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 android.hardware.audio.core;
+
+import android.hardware.common.Ashmem;
+
+/**
+ * MMap buffer descriptor is used by streams opened in MMap No IRQ mode.
+ */
+@JavaDerive(equals=true, toString=true)
+@VintfStability
+parcelable MmapBufferDescriptor {
+    /**
+     * MMap memory buffer.
+     */
+    Ashmem sharedMemory;
+    /**
+     * Transfer size granularity in frames.
+     */
+    long burstSizeFrames;
+    /**
+     * Attributes describing the buffer. Bitmask indexed by FLAG_INDEX_*
+     * constants.
+     */
+    int flags;
+
+    /**
+     * Whether the buffer can be securely shared to untrusted applications
+     * through the AAudio exclusive mode.
+     *
+     * Only set this flag if applications are restricted from accessing the
+     * memory surrounding the audio data buffer by a kernel mechanism.
+     * See Linux kernel's dma-buf
+     * (https://www.kernel.org/doc/html/v4.16/driver-api/dma-buf.html).
+     */
+    const int FLAG_INDEX_APPLICATION_SHAREABLE = 0;
+}
diff --git a/audio/aidl/android/hardware/audio/core/StreamDescriptor.aidl b/audio/aidl/android/hardware/audio/core/StreamDescriptor.aidl
new file mode 100644
index 0000000..f2338e0
--- /dev/null
+++ b/audio/aidl/android/hardware/audio/core/StreamDescriptor.aidl
@@ -0,0 +1,201 @@
+/*
+ * Copyright (C) 2022 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 android.hardware.audio.core;
+
+import android.hardware.audio.core.MmapBufferDescriptor;
+import android.hardware.common.fmq.MQDescriptor;
+import android.hardware.common.fmq.SynchronizedReadWrite;
+import android.hardware.common.fmq.UnsynchronizedWrite;
+
+/**
+ * Stream descriptor contains fast message queues and buffers used for sending
+ * and receiving audio data. The descriptor complements IStream* interfaces by
+ * providing communication channels that serve as an alternative to Binder
+ * transactions.
+ *
+ * Handling of audio data and commands must be done by the HAL module on a
+ * dedicated thread with high priority, for all modes, including MMap No
+ * IRQ. The HAL module is responsible for creating this thread and setting its
+ * priority. The HAL module is also responsible for serializing access to the
+ * internal components of the stream while serving commands invoked via the
+ * stream's AIDL interface and commands invoked via the command queue of the
+ * descriptor.
+ */
+@JavaDerive(equals=true, toString=true)
+@VintfStability
+parcelable StreamDescriptor {
+    /**
+     * Position binds together a position within the stream and time.
+     *
+     * The timestamp must use "monotonic" clock.
+     *
+     * The frame count must advance between consecutive I/O operations, and stop
+     * advancing when the stream was put into the 'standby' mode. On exiting the
+     * 'standby' mode, the frame count must not reset, but continue counting.
+     */
+    @VintfStability
+    @FixedSize
+    parcelable Position {
+        /** Frame count. */
+        long frames;
+        /** Timestamp in nanoseconds. */
+        long timeNs;
+    }
+
+    /**
+     * The exit command is used to unblock the HAL thread and ask it to exit.
+     * This is the last command that the client sends via the StreamDescriptor.
+     * The HAL module must reply to this command in order to unblock the client,
+     * and cease waiting on the command queue.
+     */
+    const int COMMAND_EXIT = 0;
+    /**
+     * The command used for audio I/O, see 'AudioBuffer'. For MMap No IRQ mode
+     * this command only provides updated positions and latency because actual
+     * audio I/O is done via the 'AudioBuffer.mmap' shared buffer.
+     */
+    const int COMMAND_BURST = 1;
+
+    /**
+     * Used for sending commands to the HAL module. The client writes into
+     * the queue, the HAL module reads. The queue can only contain a single
+     * command.
+     */
+    @VintfStability
+    @FixedSize
+    parcelable Command {
+        /**
+         * One of COMMAND_* codes.
+         */
+        int code;
+        /**
+         * For output streams: the amount of bytes provided by the client in the
+         *   'audio.fmq' queue.
+         * For input streams: the amount of bytes requested by the client to read
+         *   from the hardware into the 'audio.fmq' queue.
+         */
+        int fmqByteCount;
+    }
+    MQDescriptor<Command, SynchronizedReadWrite> command;
+
+    /**
+     * No error, the command completed successfully.
+     */
+    const int STATUS_OK = 0;
+    /**
+     * Invalid data provided in the command, e.g. unknown command code or
+     * negative 'fmqByteCount' value.
+     */
+    const int STATUS_ILLEGAL_ARGUMENT = 1;
+    /**
+     * The HAL module is not in the state when it can complete the command.
+     */
+    const int STATUS_ILLEGAL_STATE = 2;
+
+    /**
+     * Used for providing replies to commands. The HAL module writes into
+     * the queue, the client reads. The queue can only contain a single reply,
+     * corresponding to the last command sent by the client.
+     */
+    @VintfStability
+    @FixedSize
+    parcelable Reply {
+        /**
+         * One of STATUS_* statuses.
+         */
+        int status;
+        /**
+         * For output streams: the amount of bytes actually consumed by the HAL
+         *   module from the 'audio.fmq' queue.
+         * For input streams: the amount of bytes actually provided by the HAL
+         *   in the 'audio.fmq' queue.
+         */
+        int fmqByteCount;
+        /**
+         * For output streams: the moment when the specified stream position
+         *   was presented to an external observer (i.e. presentation position).
+         * For input streams: the moment when data at the specified stream position
+         *   was acquired (i.e. capture position).
+         */
+        Position observable;
+        /**
+         * Used only for MMap streams to provide the hardware read / write
+         * position for audio data in the shared memory buffer 'audio.mmap'.
+         */
+        Position hardware;
+        /**
+         * Current latency reported by the hardware.
+         */
+        int latencyMs;
+    }
+    MQDescriptor<Reply, SynchronizedReadWrite> reply;
+
+    /**
+     * Total buffer size in frames. This applies both to the size of the 'audio.fmq'
+     * queue and to the size of the shared memory buffer for MMap No IRQ streams.
+     * Note that this size may end up being slightly larger than the size requested
+     * in a call to 'IModule.openInputStream' or 'openOutputStream' due to memory
+     * alignment requirements.
+     */
+    long bufferSizeFrames;
+
+    /**
+     * Used for sending or receiving audio data to/from the stream. In the case
+     * of MMap No IRQ streams this structure only contains the information about
+     * the shared memory buffer. Audio data is sent via the shared buffer
+     * directly.
+     */
+    @VintfStability
+    union AudioBuffer {
+        /**
+         * The fast message queue used for all modes except MMap No IRQ. Access
+         * to this queue is synchronized via the 'command' and 'reply' queues
+         * as described below.
+         *
+         * For output streams the following sequence of operations is used:
+         *  1. The client puts audio data into the 'audio.fmq' queue.
+         *  2. The client writes the 'BURST' command into the 'command' queue,
+         *     and hangs on waiting on a read from the 'reply' queue.
+         *  3. The high priority thread in the HAL module wakes up due to 2.
+         *  4. The HAL module reads the command and audio data.
+         *  5. The HAL module writes the command status and current positions
+         *     into 'reply' queue, and hangs on waiting on a read from
+         *     the 'command' queue.
+         *
+         * For input streams the following sequence of operations is used:
+         *  1. The client writes the 'BURST' command into the 'command' queue,
+         *     and hangs on waiting on a read from the 'reply' queue.
+         *  2. The high priority thread in the HAL module wakes up due to 1.
+         *  3. The HAL module puts audio data into the 'audio.fmq' queue.
+         *  4. The HAL module writes the command status and current positions
+         *     into 'reply' queue, and hangs on waiting on a read from
+         *     the 'command' queue.
+         *  5. The client wakes up due to 4.
+         *  6. The client reads the reply and audio data.
+         */
+        MQDescriptor<byte, UnsynchronizedWrite> fmq;
+        /**
+         * MMap buffers are shared directly with the DSP, which operates
+         * independently from the CPU. Writes and reads into these buffers
+         * are not synchronized with 'command' and 'reply' queues. However,
+         * the client still uses the 'BURST' command for obtaining current
+         * positions from the HAL module.
+         */
+        MmapBufferDescriptor mmap;
+    }
+    AudioBuffer audio;
+}
diff --git a/audio/aidl/default/Android.bp b/audio/aidl/default/Android.bp
index ad1d9c7..027d928 100644
--- a/audio/aidl/default/Android.bp
+++ b/audio/aidl/default/Android.bp
@@ -16,6 +16,8 @@
         "libstagefright_foundation",
         "android.media.audio.common.types-V1-ndk",
         "android.hardware.audio.core-V1-ndk",
+        "android.hardware.common-V2-ndk",
+        "android.hardware.common.fmq-V1-ndk",
     ],
     export_include_dirs: ["include"],
     srcs: [
@@ -41,6 +43,8 @@
         "libstagefright_foundation",
         "android.media.audio.common.types-V1-ndk",
         "android.hardware.audio.core-V1-ndk",
+        "android.hardware.common-V2-ndk",
+        "android.hardware.common.fmq-V1-ndk",
     ],
     static_libs: [
         "libaudioserviceexampleimpl",
diff --git a/audio/aidl/default/Module.cpp b/audio/aidl/default/Module.cpp
index 5b4d48a..1c6f90a 100644
--- a/audio/aidl/default/Module.cpp
+++ b/audio/aidl/default/Module.cpp
@@ -27,7 +27,9 @@
 
 using aidl::android::hardware::audio::common::SinkMetadata;
 using aidl::android::hardware::audio::common::SourceMetadata;
+using aidl::android::media::audio::common::AudioChannelLayout;
 using aidl::android::media::audio::common::AudioFormatDescription;
+using aidl::android::media::audio::common::AudioFormatType;
 using aidl::android::media::audio::common::AudioIoFlags;
 using aidl::android::media::audio::common::AudioOffloadInfo;
 using aidl::android::media::audio::common::AudioOutputFlags;
@@ -36,6 +38,7 @@
 using aidl::android::media::audio::common::AudioPortExt;
 using aidl::android::media::audio::common::AudioProfile;
 using aidl::android::media::audio::common::Int;
+using aidl::android::media::audio::common::PcmType;
 
 namespace aidl::android::hardware::audio::core {
 
@@ -69,6 +72,49 @@
     return true;
 }
 
+constexpr size_t getPcmSampleSizeInBytes(PcmType pcm) {
+    switch (pcm) {
+        case PcmType::UINT_8_BIT:
+            return 1;
+        case PcmType::INT_16_BIT:
+            return 2;
+        case PcmType::INT_32_BIT:
+            return 4;
+        case PcmType::FIXED_Q_8_24:
+            return 4;
+        case PcmType::FLOAT_32_BIT:
+            return 4;
+        case PcmType::INT_24_BIT:
+            return 3;
+    }
+    return 0;
+}
+
+constexpr size_t getChannelCount(const AudioChannelLayout& layout) {
+    using Tag = AudioChannelLayout::Tag;
+    switch (layout.getTag()) {
+        case Tag::none:
+            return 0;
+        case Tag::invalid:
+            return 0;
+        case Tag::indexMask:
+            return __builtin_popcount(layout.get<Tag::indexMask>());
+        case Tag::layoutMask:
+            return __builtin_popcount(layout.get<Tag::layoutMask>());
+        case Tag::voiceMask:
+            return __builtin_popcount(layout.get<Tag::voiceMask>());
+    }
+    return 0;
+}
+
+size_t getFrameSizeInBytes(const AudioFormatDescription& format, const AudioChannelLayout& layout) {
+    if (format.type == AudioFormatType::PCM) {
+        return getPcmSampleSizeInBytes(format.pcm) * getChannelCount(layout);
+    }
+    // For non-PCM formats always use frame size of 1.
+    return 1;
+}
+
 bool findAudioProfile(const AudioPort& port, const AudioFormatDescription& format,
                       AudioProfile* profile) {
     if (auto profilesIt =
@@ -111,6 +157,78 @@
     erase_all_values(mPatches, erasedPatches);
 }
 
+ndk::ScopedAStatus Module::createStreamDescriptor(int32_t in_portConfigId,
+                                                  int64_t in_bufferSizeFrames,
+                                                  StreamDescriptor* out_descriptor) {
+    if (in_bufferSizeFrames <= 0) {
+        LOG(ERROR) << __func__ << ": non-positive buffer size " << in_bufferSizeFrames;
+        return ndk::ScopedAStatus::fromExceptionCode(EX_ILLEGAL_ARGUMENT);
+    }
+    if (in_bufferSizeFrames < kMinimumStreamBufferSizeFrames) {
+        LOG(ERROR) << __func__ << ": insufficient buffer size " << in_bufferSizeFrames
+                   << ", must be at least " << kMinimumStreamBufferSizeFrames;
+        return ndk::ScopedAStatus::fromExceptionCode(EX_ILLEGAL_ARGUMENT);
+    }
+    auto& configs = getConfig().portConfigs;
+    auto portConfigIt = findById<AudioPortConfig>(configs, in_portConfigId);
+    // Since 'createStreamDescriptor' is an internal method, it is assumed that
+    // validity of the portConfigId has already been checked.
+    const size_t frameSize =
+            getFrameSizeInBytes(portConfigIt->format.value(), portConfigIt->channelMask.value());
+    if (frameSize == 0) {
+        LOG(ERROR) << __func__ << ": could not calculate frame size for port config "
+                   << portConfigIt->toString();
+        return ndk::ScopedAStatus::fromExceptionCode(EX_ILLEGAL_ARGUMENT);
+    }
+    LOG(DEBUG) << __func__ << ": frame size " << frameSize << " bytes";
+    if (frameSize > kMaximumStreamBufferSizeBytes / in_bufferSizeFrames) {
+        LOG(ERROR) << __func__ << ": buffer size " << in_bufferSizeFrames
+                   << " frames is too large, maximum size is "
+                   << kMaximumStreamBufferSizeBytes / frameSize;
+        return ndk::ScopedAStatus::fromExceptionCode(EX_ILLEGAL_ARGUMENT);
+    }
+    (void)out_descriptor;
+    return ndk::ScopedAStatus::ok();
+}
+
+ndk::ScopedAStatus Module::findPortIdForNewStream(int32_t in_portConfigId, AudioPort** port) {
+    auto& configs = getConfig().portConfigs;
+    auto portConfigIt = findById<AudioPortConfig>(configs, in_portConfigId);
+    if (portConfigIt == configs.end()) {
+        LOG(ERROR) << __func__ << ": existing port config id " << in_portConfigId << " not found";
+        return ndk::ScopedAStatus::fromExceptionCode(EX_ILLEGAL_ARGUMENT);
+    }
+    const int32_t portId = portConfigIt->portId;
+    // In our implementation, configs of mix ports always have unique IDs.
+    CHECK(portId != in_portConfigId);
+    auto& ports = getConfig().ports;
+    auto portIt = findById<AudioPort>(ports, portId);
+    if (portIt == ports.end()) {
+        LOG(ERROR) << __func__ << ": port id " << portId << " used by port config id "
+                   << in_portConfigId << " not found";
+        return ndk::ScopedAStatus::fromExceptionCode(EX_ILLEGAL_ARGUMENT);
+    }
+    if (mStreams.count(in_portConfigId) != 0) {
+        LOG(ERROR) << __func__ << ": port config id " << in_portConfigId
+                   << " already has a stream opened on it";
+        return ndk::ScopedAStatus::fromExceptionCode(EX_ILLEGAL_STATE);
+    }
+    if (portIt->ext.getTag() != AudioPortExt::Tag::mix) {
+        LOG(ERROR) << __func__ << ": port config id " << in_portConfigId
+                   << " does not correspond to a mix port";
+        return ndk::ScopedAStatus::fromExceptionCode(EX_ILLEGAL_ARGUMENT);
+    }
+    const int32_t maxOpenStreamCount = portIt->ext.get<AudioPortExt::Tag::mix>().maxOpenStreamCount;
+    if (maxOpenStreamCount != 0 && mStreams.count(portId) >= maxOpenStreamCount) {
+        LOG(ERROR) << __func__ << ": port id " << portId
+                   << " has already reached maximum allowed opened stream count: "
+                   << maxOpenStreamCount;
+        return ndk::ScopedAStatus::fromExceptionCode(EX_ILLEGAL_STATE);
+    }
+    *port = &(*portIt);
+    return ndk::ScopedAStatus::ok();
+}
+
 internal::Configuration& Module::getConfig() {
     if (!mConfig) {
         mConfig.reset(new internal::Configuration(internal::getNullPrimaryConfiguration()));
@@ -336,98 +454,59 @@
     return ndk::ScopedAStatus::ok();
 }
 
-ndk::ScopedAStatus Module::openInputStream(int32_t in_portConfigId,
-                                           const SinkMetadata& in_sinkMetadata,
-                                           std::shared_ptr<IStreamIn>* _aidl_return) {
-    auto& configs = getConfig().portConfigs;
-    auto portConfigIt = findById<AudioPortConfig>(configs, in_portConfigId);
-    if (portConfigIt == configs.end()) {
-        LOG(ERROR) << __func__ << ": existing port config id " << in_portConfigId << " not found";
-        return ndk::ScopedAStatus::fromExceptionCode(EX_ILLEGAL_ARGUMENT);
+ndk::ScopedAStatus Module::openInputStream(const OpenInputStreamArguments& in_args,
+                                           OpenInputStreamReturn* _aidl_return) {
+    LOG(DEBUG) << __func__ << ": port config id " << in_args.portConfigId << ", buffer size "
+               << in_args.bufferSizeFrames << " frames";
+    AudioPort* port = nullptr;
+    if (auto status = findPortIdForNewStream(in_args.portConfigId, &port); !status.isOk()) {
+        return status;
     }
-    const int32_t portId = portConfigIt->portId;
-    // In our implementation, configs of mix ports always have unique IDs.
-    CHECK(portId != in_portConfigId);
-    auto& ports = getConfig().ports;
-    auto portIt = findById<AudioPort>(ports, portId);
-    if (portIt == ports.end()) {
-        LOG(ERROR) << __func__ << ": port id " << portId << " used by port config id "
-                   << in_portConfigId << " not found";
-        return ndk::ScopedAStatus::fromExceptionCode(EX_ILLEGAL_ARGUMENT);
-    }
-    if (portIt->flags.getTag() != AudioIoFlags::Tag::input ||
-        portIt->ext.getTag() != AudioPortExt::Tag::mix) {
-        LOG(ERROR) << __func__ << ": port config id " << in_portConfigId
+    if (port->flags.getTag() != AudioIoFlags::Tag::input) {
+        LOG(ERROR) << __func__ << ": port config id " << in_args.portConfigId
                    << " does not correspond to an input mix port";
         return ndk::ScopedAStatus::fromExceptionCode(EX_ILLEGAL_ARGUMENT);
     }
-    if (mStreams.count(in_portConfigId) != 0) {
-        LOG(ERROR) << __func__ << ": port config id " << in_portConfigId
-                   << " already has a stream opened on it";
-        return ndk::ScopedAStatus::fromExceptionCode(EX_ILLEGAL_STATE);
+    if (auto status = createStreamDescriptor(in_args.portConfigId, in_args.bufferSizeFrames,
+                                             &_aidl_return->desc);
+        !status.isOk()) {
+        return status;
     }
-    const int32_t maxOpenStreamCount = portIt->ext.get<AudioPortExt::Tag::mix>().maxOpenStreamCount;
-    if (maxOpenStreamCount != 0 && mStreams.count(portId) >= maxOpenStreamCount) {
-        LOG(ERROR) << __func__ << ": port id " << portId
-                   << " has already reached maximum allowed opened stream count: "
-                   << maxOpenStreamCount;
-        return ndk::ScopedAStatus::fromExceptionCode(EX_ILLEGAL_STATE);
-    }
-    auto stream = ndk::SharedRefBase::make<StreamIn>(in_sinkMetadata);
-    mStreams.insert(portId, in_portConfigId, StreamWrapper(stream));
-    *_aidl_return = std::move(stream);
+    auto stream = ndk::SharedRefBase::make<StreamIn>(in_args.sinkMetadata);
+    mStreams.insert(port->id, in_args.portConfigId, StreamWrapper(stream));
+    _aidl_return->stream = std::move(stream);
     return ndk::ScopedAStatus::ok();
 }
 
-ndk::ScopedAStatus Module::openOutputStream(int32_t in_portConfigId,
-                                            const SourceMetadata& in_sourceMetadata,
-                                            const std::optional<AudioOffloadInfo>& in_offloadInfo,
-                                            std::shared_ptr<IStreamOut>* _aidl_return) {
-    auto& configs = getConfig().portConfigs;
-    auto portConfigIt = findById<AudioPortConfig>(configs, in_portConfigId);
-    if (portConfigIt == configs.end()) {
-        LOG(ERROR) << __func__ << ": existing port config id " << in_portConfigId << " not found";
-        return ndk::ScopedAStatus::fromExceptionCode(EX_ILLEGAL_ARGUMENT);
+ndk::ScopedAStatus Module::openOutputStream(const OpenOutputStreamArguments& in_args,
+                                            OpenOutputStreamReturn* _aidl_return) {
+    LOG(DEBUG) << __func__ << ": port config id " << in_args.portConfigId << ", has offload info? "
+               << (in_args.offloadInfo.has_value()) << ", buffer size " << in_args.bufferSizeFrames
+               << " frames";
+    AudioPort* port = nullptr;
+    if (auto status = findPortIdForNewStream(in_args.portConfigId, &port); !status.isOk()) {
+        return status;
     }
-    const int32_t portId = portConfigIt->portId;
-    // In our implementation, configs of mix ports always have unique IDs.
-    CHECK(portId != in_portConfigId);
-    auto& ports = getConfig().ports;
-    auto portIt = findById<AudioPort>(ports, portId);
-    if (portIt == ports.end()) {
-        LOG(ERROR) << __func__ << ": port id " << portId << " used by port config id "
-                   << in_portConfigId << " not found";
-        return ndk::ScopedAStatus::fromExceptionCode(EX_ILLEGAL_ARGUMENT);
-    }
-    if (portIt->flags.getTag() != AudioIoFlags::Tag::output ||
-        portIt->ext.getTag() != AudioPortExt::Tag::mix) {
-        LOG(ERROR) << __func__ << ": port config id " << in_portConfigId
+    if (port->flags.getTag() != AudioIoFlags::Tag::output) {
+        LOG(ERROR) << __func__ << ": port config id " << in_args.portConfigId
                    << " does not correspond to an output mix port";
         return ndk::ScopedAStatus::fromExceptionCode(EX_ILLEGAL_ARGUMENT);
     }
-    if (portConfigIt->flags.has_value() &&
-        ((portConfigIt->flags.value().get<AudioIoFlags::Tag::output>() &
-          1 << static_cast<int32_t>(AudioOutputFlags::COMPRESS_OFFLOAD)) != 0) &&
-        !in_offloadInfo.has_value()) {
-        LOG(ERROR) << __func__ << ": port config id " << in_portConfigId
+    if ((port->flags.get<AudioIoFlags::Tag::output>() &
+         1 << static_cast<int32_t>(AudioOutputFlags::COMPRESS_OFFLOAD)) != 0 &&
+        !in_args.offloadInfo.has_value()) {
+        LOG(ERROR) << __func__ << ": port id " << port->id
                    << " has COMPRESS_OFFLOAD flag set, requires offload info";
         return ndk::ScopedAStatus::fromExceptionCode(EX_ILLEGAL_ARGUMENT);
     }
-    if (mStreams.count(in_portConfigId) != 0) {
-        LOG(ERROR) << __func__ << ": port config id " << in_portConfigId
-                   << " already has a stream opened on it";
-        return ndk::ScopedAStatus::fromExceptionCode(EX_ILLEGAL_STATE);
+    if (auto status = createStreamDescriptor(in_args.portConfigId, in_args.bufferSizeFrames,
+                                             &_aidl_return->desc);
+        !status.isOk()) {
+        return status;
     }
-    const int32_t maxOpenStreamCount = portIt->ext.get<AudioPortExt::Tag::mix>().maxOpenStreamCount;
-    if (maxOpenStreamCount != 0 && mStreams.count(portId) >= maxOpenStreamCount) {
-        LOG(ERROR) << __func__ << ": port id " << portId
-                   << " has already reached maximum allowed opened stream count: "
-                   << maxOpenStreamCount;
-        return ndk::ScopedAStatus::fromExceptionCode(EX_ILLEGAL_STATE);
-    }
-    auto stream = ndk::SharedRefBase::make<StreamOut>(in_sourceMetadata, in_offloadInfo);
-    mStreams.insert(portId, in_portConfigId, StreamWrapper(stream));
-    *_aidl_return = std::move(stream);
+    auto stream = ndk::SharedRefBase::make<StreamOut>(in_args.sourceMetadata, in_args.offloadInfo);
+    mStreams.insert(port->id, in_args.portConfigId, StreamWrapper(stream));
+    _aidl_return->stream = std::move(stream);
     return ndk::ScopedAStatus::ok();
 }
 
@@ -512,6 +591,10 @@
         }
     }
     *_aidl_return = in_requested;
+    _aidl_return->minimumStreamBufferSizeFrames = kMinimumStreamBufferSizeFrames;
+    _aidl_return->latenciesMs.clear();
+    _aidl_return->latenciesMs.insert(_aidl_return->latenciesMs.end(),
+                                     _aidl_return->sinkPortConfigIds.size(), kLatencyMs);
     if (existing == patches.end()) {
         _aidl_return->id = getConfig().nextPatchId++;
         patches.push_back(*_aidl_return);
diff --git a/audio/aidl/default/Stream.cpp b/audio/aidl/default/Stream.cpp
index e16b2c6..ab3e451 100644
--- a/audio/aidl/default/Stream.cpp
+++ b/audio/aidl/default/Stream.cpp
@@ -15,7 +15,6 @@
  */
 
 #define LOG_TAG "AHAL_Stream"
-#define LOG_NDEBUG 0
 #include <android-base/logging.h>
 
 #include "core-impl/Stream.h"
@@ -26,7 +25,9 @@
 
 namespace aidl::android::hardware::audio::core {
 
-StreamIn::StreamIn(const SinkMetadata& sinkMetadata) : mMetadata(sinkMetadata) {}
+StreamIn::StreamIn(const SinkMetadata& sinkMetadata) : mMetadata(sinkMetadata) {
+    LOG(DEBUG) << __func__;
+}
 
 ndk::ScopedAStatus StreamIn::close() {
     LOG(DEBUG) << __func__;
@@ -51,7 +52,9 @@
 
 StreamOut::StreamOut(const SourceMetadata& sourceMetadata,
                      const std::optional<AudioOffloadInfo>& offloadInfo)
-    : mMetadata(sourceMetadata), mOffloadInfo(offloadInfo) {}
+    : mMetadata(sourceMetadata), mOffloadInfo(offloadInfo) {
+    LOG(DEBUG) << __func__;
+}
 
 ndk::ScopedAStatus StreamOut::close() {
     LOG(DEBUG) << __func__;
diff --git a/audio/aidl/default/include/core-impl/Module.h b/audio/aidl/default/include/core-impl/Module.h
index 81a02ba..f7e14af 100644
--- a/audio/aidl/default/include/core-impl/Module.h
+++ b/audio/aidl/default/include/core-impl/Module.h
@@ -48,15 +48,15 @@
             int32_t in_portId,
             std::vector<::aidl::android::hardware::audio::core::AudioRoute>* _aidl_return) override;
     ndk::ScopedAStatus openInputStream(
-            int32_t in_portConfigId,
-            const ::aidl::android::hardware::audio::common::SinkMetadata& in_sinkMetadata,
-            std::shared_ptr<IStreamIn>* _aidl_return) override;
+            const ::aidl::android::hardware::audio::core::IModule::OpenInputStreamArguments&
+                    in_args,
+            ::aidl::android::hardware::audio::core::IModule::OpenInputStreamReturn* _aidl_return)
+            override;
     ndk::ScopedAStatus openOutputStream(
-            int32_t in_portConfigId,
-            const ::aidl::android::hardware::audio::common::SourceMetadata& in_sourceMetadata,
-            const std::optional<::aidl::android::media::audio::common::AudioOffloadInfo>&
-                    in_offloadInfo,
-            std::shared_ptr<IStreamOut>* _aidl_return) override;
+            const ::aidl::android::hardware::audio::core::IModule::OpenOutputStreamArguments&
+                    in_args,
+            ::aidl::android::hardware::audio::core::IModule::OpenOutputStreamReturn* _aidl_return)
+            override;
     ndk::ScopedAStatus setAudioPatch(const AudioPatch& in_requested,
                                      AudioPatch* _aidl_return) override;
     ndk::ScopedAStatus setAudioPortConfig(
@@ -69,9 +69,21 @@
   private:
     void cleanUpPatch(int32_t patchId);
     void cleanUpPatches(int32_t portConfigId);
+    ndk::ScopedAStatus createStreamDescriptor(
+            int32_t in_portConfigId, int64_t in_bufferSizeFrames,
+            ::aidl::android::hardware::audio::core::StreamDescriptor* out_descriptor);
+    ndk::ScopedAStatus findPortIdForNewStream(
+            int32_t in_portConfigId, ::aidl::android::media::audio::common::AudioPort** port);
     internal::Configuration& getConfig();
     void registerPatch(const AudioPatch& patch);
 
+    // This value is used for all AudioPatches.
+    static constexpr int32_t kMinimumStreamBufferSizeFrames = 16;
+    // This value is used for all AudioPatches.
+    static constexpr int32_t kLatencyMs = 10;
+    // The maximum stream buffer size is 1 GiB = 2 ** 30 bytes;
+    static constexpr int32_t kMaximumStreamBufferSizeBytes = 1 << 30;
+
     std::unique_ptr<internal::Configuration> mConfig;
     ModuleDebug mDebug;
     // ids of ports created at runtime via 'connectExternalDevice'.
diff --git a/audio/aidl/vts/Android.bp b/audio/aidl/vts/Android.bp
index cd5915b..75ff37f 100644
--- a/audio/aidl/vts/Android.bp
+++ b/audio/aidl/vts/Android.bp
@@ -23,6 +23,8 @@
     static_libs: [
         "android.hardware.audio.common-V1-ndk",
         "android.hardware.audio.core-V1-ndk",
+        "android.hardware.common-V2-ndk",
+        "android.hardware.common.fmq-V1-ndk",
         "android.media.audio.common.types-V1-ndk",
     ],
     test_suites: [
diff --git a/audio/aidl/vts/VtsHalAudioCoreTargetTest.cpp b/audio/aidl/vts/VtsHalAudioCoreTargetTest.cpp
index bb24365..0ecc057 100644
--- a/audio/aidl/vts/VtsHalAudioCoreTargetTest.cpp
+++ b/audio/aidl/vts/VtsHalAudioCoreTargetTest.cpp
@@ -16,6 +16,7 @@
 
 #include <algorithm>
 #include <condition_variable>
+#include <limits>
 #include <memory>
 #include <mutex>
 #include <optional>
@@ -48,6 +49,7 @@
 using aidl::android::hardware::audio::core::IStreamIn;
 using aidl::android::hardware::audio::core::IStreamOut;
 using aidl::android::hardware::audio::core::ModuleDebug;
+using aidl::android::hardware::audio::core::StreamDescriptor;
 using aidl::android::media::audio::common::AudioContentType;
 using aidl::android::media::audio::common::AudioDevice;
 using aidl::android::media::audio::common::AudioDeviceAddress;
@@ -225,6 +227,9 @@
 
 class AudioCoreModule : public testing::TestWithParam<std::string> {
   public:
+    // The default buffer size is used mostly for negative tests.
+    static constexpr int kDefaultBufferSize = 256;
+
     void SetUp() override {
         ASSERT_NO_FATAL_FAILURE(ConnectToService());
         debug.flags().simulateDeviceConnections = true;
@@ -382,13 +387,14 @@
         }
     }
     void SetUpPortConfig(IModule* module) { ASSERT_NO_FATAL_FAILURE(mPortConfig.SetUp(module)); }
-    ScopedAStatus SetUpNoChecks(IModule* module) {
-        return SetUpNoChecks(module, mPortConfig.get());
+    ScopedAStatus SetUpNoChecks(IModule* module, long bufferSize) {
+        return SetUpNoChecks(module, mPortConfig.get(), bufferSize);
     }
-    ScopedAStatus SetUpNoChecks(IModule* module, const AudioPortConfig& portConfig);
-    void SetUp(IModule* module) {
+    ScopedAStatus SetUpNoChecks(IModule* module, const AudioPortConfig& portConfig,
+                                long bufferSize);
+    void SetUp(IModule* module, long bufferSize) {
         ASSERT_NO_FATAL_FAILURE(SetUpPortConfig(module));
-        ScopedAStatus status = SetUpNoChecks(module);
+        ScopedAStatus status = SetUpNoChecks(module, bufferSize);
         ASSERT_EQ(EX_NONE, status.getExceptionCode())
                 << status << "; port config id " << getPortId();
         ASSERT_NE(nullptr, mStream) << "; port config id " << getPortId();
@@ -401,6 +407,7 @@
   private:
     WithAudioPortConfig mPortConfig;
     std::shared_ptr<Stream> mStream;
+    StreamDescriptor mDescriptor;
 };
 
 SinkMetadata GenerateSinkMetadata(const AudioPortConfig& portConfig) {
@@ -415,8 +422,19 @@
 
 template <>
 ScopedAStatus WithStream<IStreamIn>::SetUpNoChecks(IModule* module,
-                                                   const AudioPortConfig& portConfig) {
-    return module->openInputStream(portConfig.id, GenerateSinkMetadata(portConfig), &mStream);
+                                                   const AudioPortConfig& portConfig,
+                                                   long bufferSize) {
+    aidl::android::hardware::audio::core::IModule::OpenInputStreamArguments args;
+    args.portConfigId = portConfig.id;
+    args.sinkMetadata = GenerateSinkMetadata(portConfig);
+    args.bufferSizeFrames = bufferSize;
+    aidl::android::hardware::audio::core::IModule::OpenInputStreamReturn ret;
+    ScopedAStatus status = module->openInputStream(args, &ret);
+    if (status.isOk()) {
+        mStream = std::move(ret.stream);
+        mDescriptor = std::move(ret.desc);
+    }
+    return status;
 }
 
 SourceMetadata GenerateSourceMetadata(const AudioPortConfig& portConfig) {
@@ -432,10 +450,20 @@
 
 template <>
 ScopedAStatus WithStream<IStreamOut>::SetUpNoChecks(IModule* module,
-                                                    const AudioPortConfig& portConfig) {
-    return module->openOutputStream(portConfig.id, GenerateSourceMetadata(portConfig),
-                                    ModuleConfig::generateOffloadInfoIfNeeded(portConfig),
-                                    &mStream);
+                                                    const AudioPortConfig& portConfig,
+                                                    long bufferSize) {
+    aidl::android::hardware::audio::core::IModule::OpenOutputStreamArguments args;
+    args.portConfigId = portConfig.id;
+    args.sourceMetadata = GenerateSourceMetadata(portConfig);
+    args.offloadInfo = ModuleConfig::generateOffloadInfoIfNeeded(portConfig);
+    args.bufferSizeFrames = bufferSize;
+    aidl::android::hardware::audio::core::IModule::OpenOutputStreamReturn ret;
+    ScopedAStatus status = module->openOutputStream(args, &ret);
+    if (status.isOk()) {
+        mStream = std::move(ret.stream);
+        mDescriptor = std::move(ret.desc);
+    }
+    return status;
 }
 
 class WithAudioPatch {
@@ -467,6 +495,10 @@
         ASSERT_EQ(EX_NONE, status.getExceptionCode())
                 << status << "; source port config id " << mSrcPortConfig.getId()
                 << "; sink port config id " << mSinkPortConfig.getId();
+        EXPECT_GT(mPatch.minimumStreamBufferSizeFrames, 0) << "patch id " << getId();
+        for (auto latencyMs : mPatch.latenciesMs) {
+            EXPECT_GT(latencyMs, 0) << "patch id " << getId();
+        }
     }
     int32_t getId() const { return mPatch.id; }
     const AudioPatch& get() const { return mPatch; }
@@ -739,18 +771,24 @@
     ASSERT_NO_FATAL_FAILURE(GetAllPortConfigIds(&portConfigIds));
     for (const auto portConfigId : GetNonExistentIds(portConfigIds)) {
         {
-            std::shared_ptr<IStreamIn> stream;
-            ScopedAStatus status = module->openInputStream(portConfigId, {}, &stream);
+            aidl::android::hardware::audio::core::IModule::OpenInputStreamArguments args;
+            args.portConfigId = portConfigId;
+            args.bufferSizeFrames = kDefaultBufferSize;
+            aidl::android::hardware::audio::core::IModule::OpenInputStreamReturn ret;
+            ScopedAStatus status = module->openInputStream(args, &ret);
             EXPECT_EQ(EX_ILLEGAL_ARGUMENT, status.getExceptionCode())
                     << status << " openInputStream returned for port config ID " << portConfigId;
-            EXPECT_EQ(nullptr, stream);
+            EXPECT_EQ(nullptr, ret.stream);
         }
         {
-            std::shared_ptr<IStreamOut> stream;
-            ScopedAStatus status = module->openOutputStream(portConfigId, {}, {}, &stream);
+            aidl::android::hardware::audio::core::IModule::OpenOutputStreamArguments args;
+            args.portConfigId = portConfigId;
+            args.bufferSizeFrames = kDefaultBufferSize;
+            aidl::android::hardware::audio::core::IModule::OpenOutputStreamReturn ret;
+            ScopedAStatus status = module->openOutputStream(args, &ret);
             EXPECT_EQ(EX_ILLEGAL_ARGUMENT, status.getExceptionCode())
                     << status << " openOutputStream returned for port config ID " << portConfigId;
-            EXPECT_EQ(nullptr, stream);
+            EXPECT_EQ(nullptr, ret.stream);
         }
     }
 }
@@ -1120,7 +1158,7 @@
         std::shared_ptr<Stream> heldStream;
         {
             WithStream<Stream> stream(portConfig.value());
-            ASSERT_NO_FATAL_FAILURE(stream.SetUp(module.get()));
+            ASSERT_NO_FATAL_FAILURE(stream.SetUp(module.get(), kDefaultBufferSize));
             heldStream = stream.getSharedPointer();
         }
         ScopedAStatus status = heldStream->close();
@@ -1132,10 +1170,43 @@
         const auto allPortConfigs = moduleConfig->getPortConfigsForMixPorts(IsInput<Stream>());
         for (const auto& portConfig : allPortConfigs) {
             WithStream<Stream> stream(portConfig);
-            ASSERT_NO_FATAL_FAILURE(stream.SetUp(module.get()));
+            ASSERT_NO_FATAL_FAILURE(stream.SetUp(module.get(), kDefaultBufferSize));
         }
     }
 
+    void OpenInvalidBufferSize() {
+        const auto portConfig = moduleConfig->getSingleConfigForMixPort(IsInput<Stream>());
+        if (!portConfig.has_value()) {
+            GTEST_SKIP() << "No mix port for attached devices";
+        }
+        WithStream<Stream> stream(portConfig.value());
+        ASSERT_NO_FATAL_FAILURE(stream.SetUpPortConfig(module.get()));
+        // The buffer size of 1 frame should be impractically small, and thus
+        // less than any minimum buffer size suggested by any HAL.
+        for (long bufferSize : std::array<long, 4>{-1, 0, 1, std::numeric_limits<long>::max()}) {
+            ScopedAStatus status = stream.SetUpNoChecks(module.get(), bufferSize);
+            EXPECT_EQ(EX_ILLEGAL_ARGUMENT, status.getExceptionCode())
+                    << status << " open" << direction(true) << "Stream returned for " << bufferSize
+                    << " buffer size";
+            EXPECT_EQ(nullptr, stream.get());
+        }
+    }
+
+    void OpenInvalidDirection() {
+        // Important! The direction of the port config must be reversed.
+        const auto portConfig = moduleConfig->getSingleConfigForMixPort(!IsInput<Stream>());
+        if (!portConfig.has_value()) {
+            GTEST_SKIP() << "No mix port for attached devices";
+        }
+        WithStream<Stream> stream(portConfig.value());
+        ASSERT_NO_FATAL_FAILURE(stream.SetUpPortConfig(module.get()));
+        ScopedAStatus status = stream.SetUpNoChecks(module.get(), kDefaultBufferSize);
+        EXPECT_EQ(EX_ILLEGAL_ARGUMENT, status.getExceptionCode())
+                << status << " open" << direction(true) << "Stream returned for port config ID "
+                << stream.getPortId();
+        EXPECT_EQ(nullptr, stream.get());
+    }
+
     void OpenOverMaxCount() {
         constexpr bool isInput = IsInput<Stream>();
         auto ports = moduleConfig->getMixPorts(isInput);
@@ -1158,10 +1229,10 @@
                 streamWraps[i].emplace(portConfigs[i]);
                 WithStream<Stream>& stream = streamWraps[i].value();
                 if (i < maxStreamCount) {
-                    ASSERT_NO_FATAL_FAILURE(stream.SetUp(module.get()));
+                    ASSERT_NO_FATAL_FAILURE(stream.SetUp(module.get(), kDefaultBufferSize));
                 } else {
                     ASSERT_NO_FATAL_FAILURE(stream.SetUpPortConfig(module.get()));
-                    ScopedAStatus status = stream.SetUpNoChecks(module.get());
+                    ScopedAStatus status = stream.SetUpNoChecks(module.get(), kDefaultBufferSize);
                     EXPECT_EQ(EX_ILLEGAL_STATE, status.getExceptionCode())
                             << status << " open" << direction(true)
                             << "Stream returned for port config ID " << stream.getPortId()
@@ -1175,21 +1246,6 @@
         }
     }
 
-    void OpenInvalidDirection() {
-        // Important! The direction of the port config must be reversed.
-        const auto portConfig = moduleConfig->getSingleConfigForMixPort(!IsInput<Stream>());
-        if (!portConfig.has_value()) {
-            GTEST_SKIP() << "No mix port for attached devices";
-        }
-        WithStream<Stream> stream(portConfig.value());
-        ASSERT_NO_FATAL_FAILURE(stream.SetUpPortConfig(module.get()));
-        ScopedAStatus status = stream.SetUpNoChecks(module.get());
-        EXPECT_EQ(EX_ILLEGAL_ARGUMENT, status.getExceptionCode())
-                << status << " open" << direction(true) << "Stream returned for port config ID "
-                << stream.getPortId();
-        EXPECT_EQ(nullptr, stream.get());
-    }
-
     void OpenTwiceSamePortConfig() {
         const auto portConfig = moduleConfig->getSingleConfigForMixPort(IsInput<Stream>());
         if (!portConfig.has_value()) {
@@ -1204,7 +1260,7 @@
             GTEST_SKIP() << "No mix port for attached devices";
         }
         WithStream<Stream> stream(portConfig.value());
-        ASSERT_NO_FATAL_FAILURE(stream.SetUp(module.get()));
+        ASSERT_NO_FATAL_FAILURE(stream.SetUp(module.get(), kDefaultBufferSize));
         ScopedAStatus status = module->resetAudioPortConfig(stream.getPortId());
         EXPECT_EQ(EX_ILLEGAL_STATE, status.getExceptionCode())
                 << status << " returned for port config ID " << stream.getPortId();
@@ -1212,9 +1268,10 @@
 
     void OpenTwiceSamePortConfigImpl(const AudioPortConfig& portConfig) {
         WithStream<Stream> stream1(portConfig);
-        ASSERT_NO_FATAL_FAILURE(stream1.SetUp(module.get()));
+        ASSERT_NO_FATAL_FAILURE(stream1.SetUp(module.get(), kDefaultBufferSize));
         WithStream<Stream> stream2;
-        ScopedAStatus status = stream2.SetUpNoChecks(module.get(), stream1.getPortConfig());
+        ScopedAStatus status =
+                stream2.SetUpNoChecks(module.get(), stream1.getPortConfig(), kDefaultBufferSize);
         EXPECT_EQ(EX_ILLEGAL_STATE, status.getExceptionCode())
                 << status << " when opening " << direction(false)
                 << " stream twice for the same port config ID " << stream1.getPortId();
@@ -1238,6 +1295,7 @@
 
 TEST_IO_STREAM(CloseTwice);
 TEST_IO_STREAM(OpenAllConfigs);
+TEST_IO_STREAM(OpenInvalidBufferSize);
 TEST_IO_STREAM(OpenInvalidDirection);
 TEST_IO_STREAM(OpenOverMaxCount);
 TEST_IO_STREAM(OpenTwiceSamePortConfig);
@@ -1277,10 +1335,14 @@
     const auto portConfig = moduleConfig->getSingleConfigForMixPort(false, *offloadPortIt);
     ASSERT_TRUE(portConfig.has_value())
             << "No profiles specified for the compressed offload mix port";
+    StreamDescriptor descriptor;
     std::shared_ptr<IStreamOut> ignored;
-    ScopedAStatus status = module->openOutputStream(portConfig.value().id,
-                                                    GenerateSourceMetadata(portConfig.value()),
-                                                    {} /* offloadInfo */, &ignored);
+    aidl::android::hardware::audio::core::IModule::OpenOutputStreamArguments args;
+    args.portConfigId = portConfig.value().id;
+    args.sourceMetadata = GenerateSourceMetadata(portConfig.value());
+    args.bufferSizeFrames = kDefaultBufferSize;
+    aidl::android::hardware::audio::core::IModule::OpenOutputStreamReturn ret;
+    ScopedAStatus status = module->openOutputStream(args, &ret);
     EXPECT_EQ(EX_ILLEGAL_ARGUMENT, status.getExceptionCode())
             << status
             << " returned when no offload info is provided for a compressed offload mix port";