Introduce soundtrigger HAL v3

This is the initial AIDL version of the soundtrigger HAL.
It is functionally equivalent to v2.4 (HIDL), but with a clean-up
interface that removes obsolete / legacy functionality and conforms to
AIDL style.

Test: Mocked the HAL and observed framework logs for basic use-cases.
Change-Id: I4525301ad1205cf41937a98b7b9f67f052cb5bd9
diff --git a/compatibility_matrices/compatibility_matrix.current.xml b/compatibility_matrices/compatibility_matrix.current.xml
index bb53654..6ea6783 100644
--- a/compatibility_matrices/compatibility_matrix.current.xml
+++ b/compatibility_matrices/compatibility_matrix.current.xml
@@ -527,6 +527,14 @@
             <instance>default</instance>
         </interface>
     </hal>
+    <hal format="aidl" optional="true">
+         <name>android.hardware.soundtrigger3</name>
+         <version>1</version>
+         <interface>
+             <name>ISoundTriggerHw</name>
+             <instance>default</instance>
+         </interface>
+    </hal>
     <hal format="hidl" optional="true">
         <name>android.hardware.tetheroffload.config</name>
         <version>1.0</version>
diff --git a/soundtrigger/3/Android.bp b/soundtrigger/3/Android.bp
new file mode 100644
index 0000000..e56c5ad
--- /dev/null
+++ b/soundtrigger/3/Android.bp
@@ -0,0 +1,29 @@
+aidl_interface {
+    name: "android.hardware.soundtrigger3",
+    vendor_available: true,
+    local_include_dir: "aidl",
+    flags: ["-Werror", "-Weverything", ],
+    srcs: [
+        "aidl/android/hardware/soundtrigger3/ISoundTriggerHw.aidl",
+        "aidl/android/hardware/soundtrigger3/ISoundTriggerHwCallback.aidl",
+        "aidl/android/hardware/soundtrigger3/ISoundTriggerHwGlobalCallback.aidl",
+    ],
+    stability: "vintf",
+    imports: [
+        "android.media.soundtrigger.types",
+    ],
+    backend: {
+        cpp: {
+            // prefer NDK backend which can be used anywhere
+            enabled: false,
+        },
+        java: {
+            sdk_version: "module_current",
+        },
+        ndk: {
+            vndk: {
+                enabled: true,
+            },
+        },
+    },
+}
diff --git a/soundtrigger/3/aidl/android/hardware/soundtrigger3/ISoundTriggerHw.aidl b/soundtrigger/3/aidl/android/hardware/soundtrigger3/ISoundTriggerHw.aidl
new file mode 100644
index 0000000..2a3fc64
--- /dev/null
+++ b/soundtrigger/3/aidl/android/hardware/soundtrigger3/ISoundTriggerHw.aidl
@@ -0,0 +1,269 @@
+/*
+ * Copyright 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 android.hardware.soundtrigger3;
+
+import android.hardware.soundtrigger3.ISoundTriggerHwCallback;
+import android.hardware.soundtrigger3.ISoundTriggerHwGlobalCallback;
+
+import android.media.soundtrigger.PhraseSoundModel;
+import android.media.soundtrigger.Properties;
+import android.media.soundtrigger.RecognitionConfig;
+import android.media.soundtrigger.SoundModel;
+import android.media.soundtrigger.ModelParameter;
+import android.media.soundtrigger.ModelParameterRange;
+import android.media.soundtrigger.Properties;
+import android.media.soundtrigger.RecognitionConfig;
+
+/**
+ * SoundTrigger HAL interface. Used for hardware recognition of hotwords
+ * and other sounds.
+ *
+ * Basic usage:
+ * ============
+ * ISoundTriggerHw supports the ability to have one of more  detection sessions running at a given
+ * time, and listening to acoustic events. The basic flow of setting up such a session is:
+ * - Load a model using loadSoundModel() or loadPhraseSoundModel(). The provided model object would
+ *   indicate the (implementation-specific) detection algorithm (engine) to use, as well as any
+ *   parameters applicable for this agorithm. Upon success, those methods would return a handle
+ *   which will be used to reference this model in subsequent calls.
+ * - Once the model had been successfully loaded, detection can begin by calling startRecognition().
+ * - Recognition will continue running in the background until one of the following events occurs:
+ *   - stopRecognition() has been called on this model.
+ *   - A detection has occurred.
+ *   - Detection was aborted, typically for resource constraints, for example, when a higher-
+ *     priority use-case has been initiated.
+ * - In the latter two cases, a recognition event will be sent via a the callback interface that was
+ *   registered by the client upon loading. In either case, after any of these events occur, the
+ *   detection becomes inactive and no more recognition callbacks are allowed.
+ * - The same model maybe started again at a later time, and this process may repeat as many times
+ *   as needed.
+ * - Finally, an inactive model that is no longer needed may be unloaded via unloadModel().
+ *
+ * Important notes about the threading model:
+ * ==========================================
+ * Both this interface and the corresponding callback interface use a synchronous calling
+ * convention. This model comes with some advantages, but also with some risks of deadlocks if the
+ * implementation does not handle this correctly. Please consider the following:
+ * - After stopRecognition() returns, no more recognition events for that model may be sent. This
+ *   implies that any queues holding such events must be flushed before the call returns and that
+ *   may imply that callback from the HAL to the client are done while stopRecognition() is blocked.
+ *   This is OK, and supported by the framework.
+ * - Similarly, the same relationship applies between unloadModel() and subsequent callbacks to
+ *   modelUnloaded().
+ * - Other than these two cases, calls into the HAL *MAY NOT* block on callbacks from the HAL, or
+ *   else deadlock conditions may result, which may be handled by rebooting of the HAL process and
+ *   cause service outages.
+ *
+ * Due to the asynchronous nature of recognition events and preemptive model unloading, the HAL must
+ * correctly handle requests that would have been valid before an event has been delivered, but
+ * became moot as result of the event. Namely:
+ * - stopRecognition() may be called on a model that has already delivered an event and became
+ *   inactive as a result. The HAL must return a successful return code in this case.
+ * - Furthermore, if a model is preemptively unloaded after it triggers (typically, this would
+ *   happen when it is first aborted and immediately preemptively unloaded), stopRecognition() may
+ *   be called on it. The HAL must return successfully in this case.
+ * - startRecognition() may be called on a model that has been preemptively unloaded. In this case,
+ *   the HAL must signal a ServiceSpecificException(RESOURCE_CONTENTION) to indicate that the
+ *   operation is temporarily unsuccessful.
+ * - unloadSoundModel() may be called on a model that has been preemptively unloaded. The HAL must
+ *   return a successful return code in this case. This also implies that model handles should
+ *   generally not be reused until explicitly unloaded. To avoid the rare possibility of running out
+ *   of handles, the framework may call unloadModel() on models that have been preemptively unloaded
+ *   by the HAL.
+ *
+ * Important notes about resource constraints and concurrency
+ * =========================================================
+ * Up until this version, the framework would enforce concurrency constraints expressed by the
+ * Properties presented by the soundtrigger instance. These include constraints on the maximum
+ * amount of models that can be loaded at the same time and on running recognition while capturing
+ * from the microphone.
+ * This version changes the approach for how these constraints are modeled, both offering the HAL
+ * implementation more flexibility and simplifying the framework's job in enforcing these
+ * limitations. Note that there is no change for how the framework behaves with earlier versions,
+ * everything described below only applies to this version and onward.
+ * The way this is achieved is as following:
+ * - The framework will no longer enforce constraints on concurrent loading of models, as expressed
+ *   in the Properties.maxSoundModels field (this property is merely a hint at this point and may be
+ *   deprecated in the future), or any other implicit constraints.
+ * - The framework will no longer enforce constraints on concurrency of audio recording and
+ *   soundtrigger operation, as expressed in the Properties.concurrentCapture field (this property
+ *   is merely a hint at this point and may be deprecated in the future).
+ * - The HAL implementation is free to reject loading of any model at any time by having the
+ *   respective load*() method signal a ServiceSpecificException(RESOURCE_CONTENTION).
+ * - The HAL implementation is free to reject starting of any model at any time by having the
+ *   respective start*() method signal a ServiceSpecificException(RESOURCE_CONTENTION).
+ * - The HAL implementation is free to preemptively stop a previously started model at its own
+ *   discretion (for example, if a higher priority use-case which cannot coexist with detection
+ *   has been requested). The HAL must notify the framework of the preemption by sending a
+ *   recognition event with an `ABORTED` status. The implementation must NOT attempt to restart the
+ *   recognition automatically when conditions change.
+ * - The HAL implementation is free to preemptively unload a previously loaded model at its own
+ *   discretion (for example, if a higher-priority model is being loaded and the two cannot
+ *   coexist). When doing so, it must first abort the detection if active (as per above) and then
+ *   notify the framework of the unload using the modelUnloaded() callback.
+ * - When conditions change, such that a model that couldn't previously load or start or that had
+ *   previously been preemptively stopped or unloaded, the HAL must notify the framework via the
+ *   newly added onResourcesAvailable() callback. This callback is not a guarantee that any
+ *   operation would now succeed, but merely a hint that retrying something that had previously
+ *   failed, now MAY succeed. Until this callback is invoked, the client may assume that any
+ *   operation that had previously failed or aborted would still fail if retried, so the
+ *   implementation should not forget to deliver it.
+ *   There are no guarantees regarding how the framework may respond to this event and the order in
+ *   which it may choose to reload/restart its models. Typically, as result of this event the
+ *   framework will make a single attempt per model to bring this model to its desired state
+ *   (loaded, started).
+ */
+@VintfStability
+interface ISoundTriggerHw {
+    /**
+     * Retrieve implementation properties.
+     *
+     * @return A Properties structure containing implementation description and capabilities.
+     */
+    Properties getProperties();
+
+    /**
+     * This will get called at most once per every attachment to the service.
+     *
+     * All events not tied to a specific model should go through this callback.
+     *
+     * @param callback An interface to receive global event callbacks.
+     */
+    void registerGlobalCallback(in ISoundTriggerHwGlobalCallback callback);
+
+    /**
+     * Load a sound model. Once loaded, recognition of this model can be started and stopped.
+     *
+     * @param soundModel A SoundModel structure describing the sound model to load.
+     * @param callback The callback interface on which the recognitionCallback()
+     *     method will be called upon completion and modelUnloaded() upon preemptive unload.
+     * @return A unique handle assigned by the HAL for use by the client when controlling
+     *     activity for this sound model.
+     * @throws ServiceSpecificException(RESOURCE_CONTENTION) if the model cannot be loaded due
+     *     to resource constraints. This is typically a temporary condition and the client may
+     *     retry after the onResourcesAvailable() global callback is invoked.
+     */
+    int loadSoundModel(in SoundModel soundModel, in ISoundTriggerHwCallback callback);
+
+    /**
+     * Load a key phrase sound model. Once loaded, recognition of this model can be started and
+     * stopped.
+     *
+     * @param soundModel A PhraseSoundModel structure describing the sound model to load.
+     * @param callback The callback interface on which the phraseRecognitionCallback() method will
+     *     be called upon completion and modelUnloaded() upon preempted unload.
+     * @return A unique handle assigned by the HAL for use by the framework when controlling
+     *     activity for this sound model.
+     * @throws ServiceSpecificException(RESOURCE_CONTENTION) if the model cannot be loaded due
+     *     to resource constraints. This is typically a temporary condition and the client may
+     *     retry after the onResourcesAvailable() global callback is invoked.
+     */
+    int loadPhraseSoundModel(in PhraseSoundModel soundModel, in ISoundTriggerHwCallback callback);
+
+    /**
+     * Unload a sound model. A sound model may be unloaded to free up resources and make room for a
+     * new one to overcome implementation limitations.
+     * This call is idempotent, to avoid any race conditions.
+     *
+     * @param modelHandle the handle of the sound model to unload.
+     */
+    void unloadSoundModel(in int modelHandle);
+
+    /**
+     * Start recognition on a given model.
+     * This must be called on a model that is in the stopped state.
+     * The state of this model becomes active and will remain so until explicitly stopped, or a
+     * recognition event had been delivered to the client.
+     *
+     * @param modelHandle the handle of the sound model to use for recognition
+     * @param deviceHandle The handle of the audio device to be used for recognition, as declared by
+     *     the audio subsystem.
+     * @param ioHandle A handle assigned by the framework, which will later be used to retrieve
+     *     an audio stream associated with this recognition session.
+     * @param config A RecognitionConfig structure containing attributes of the recognition to
+     *     perform.
+      * @throws ServiceSpecificException(RESOURCE_CONTENTION) if the model cannot be started due
+     *     to resource constraints. This is typically a temporary condition and the client may
+     *     retry after the onResourcesAvailable() global callback is invoked.
+    */
+    void startRecognition(in int modelHandle, in int deviceHandle,
+                          in int ioHandle, in RecognitionConfig config);
+
+    /**
+     * Stop recognition on a given model.
+     * This call is idempotent, to avoid any race conditions.
+     *
+     * @param modelHandle The handle of the sound model to use for recognition
+     */
+    void stopRecognition(in int modelHandle);
+
+    /**
+     * Request a recognition event to be generated.
+     * The model must be in the started state and will remain started after the event is sent.
+     * The model state is returned asynchronously as a RecognitionEvent via the callback that was
+     * registered upon loading. That event must have a RecognitionStatus.FORCED status.
+     *
+     * @param modelHandle The handle of the sound model whose state is being
+     *     queried.
+     */
+    void forceRecognitionEvent(in int modelHandle);
+
+    /**
+     * Get supported parameter attributes with respect to the provided model handle.
+     * Model parameters are used to query/control model-specific detection behavior during a
+     * detection session.
+     * Along with determining the valid range, this API is also used to determine if a given
+     * parameter ID is supported at all by the modelHandle for use with getParameter() and
+     * setParameter() APIs.
+     *
+     * @param modelHandle The sound model handle indicating which model to query.
+     * @param modelParam Parameter to set which will be validated against the ModelParameter type.
+     * @return This structure indicates supported attributes of the parameter for the given model
+     *      handle. If the parameter is not supported, null is returned.
+     */
+    @nullable ModelParameterRange queryParameter(in int modelHandle, in ModelParameter modelParam);
+
+    /**
+     * Get a model specific parameter.
+     * If the value has not been set, a default value is returned. See ModelParameter for parameter
+     * default values.
+     * The caller must check if the handle supports the parameter via the queryParameter API prior
+     * to calling this method.
+     *
+     * @param modelHandle The sound model associated with given modelParam
+     * @param modelParam Parameter to set which will be validated against the ModelParameter type.
+     *     Not putting ModelParameter type directly in the definition and validating internally
+     *     allows for forward compatibility.
+     * @return Value set to the requested parameter.
+     */
+    int getParameter(in int modelHandle, in ModelParameter modelParam);
+
+    /**
+     * Set a model specific parameter with the given value.
+     * This parameter will keep its value for the duration the model is loaded regardless of
+     * starting and stopping recognition. Once the model is unloaded, the value will be lost.
+     * The caller must check if the handle supports the parameter via the queryParameter API prior
+     * to calling this method.
+     *
+     * @param modelHandle The sound model handle indicating which model to modify parameters
+     * @param modelParam Parameter to set which will be validated against the ModelParameter type.
+     *     Not putting ModelParameter type directly in the definition and validating internally
+     *     allows for forward compatibility.
+     * @param value The value to set for the given model parameter.
+     */
+    void setParameter(in int modelHandle, in ModelParameter modelParam, in int value);
+}
diff --git a/soundtrigger/3/aidl/android/hardware/soundtrigger3/ISoundTriggerHwCallback.aidl b/soundtrigger/3/aidl/android/hardware/soundtrigger3/ISoundTriggerHwCallback.aidl
new file mode 100644
index 0000000..049ca65
--- /dev/null
+++ b/soundtrigger/3/aidl/android/hardware/soundtrigger3/ISoundTriggerHwCallback.aidl
@@ -0,0 +1,59 @@
+/*
+ * Copyright 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 android.hardware.soundtrigger3;
+
+import android.media.soundtrigger.PhraseRecognitionEvent;
+import android.media.soundtrigger.RecognitionEvent;
+
+/**
+ * SoundTrigger HAL per-model Callback interface.
+ */
+@VintfStability
+interface ISoundTriggerHwCallback {
+    /**
+     * Callback method called by the HAL when a model has been unloaded at the HAL implementation's
+     * discretion.
+     * This event may only be delivered when the model state is 'stopped'.
+     * This event is NOT sent as part of an unload sequence initiated by the client.
+     *
+     * @param model The model handle.
+     */
+    void modelUnloaded(in int model);
+
+    /**
+     * Callback method called by the HAL when the sound recognition triggers for a key phrase sound
+     * model.
+     * This event may only be delivered when the model state is 'started'.
+     * Unless the status of the event is RecognitionStatus.FORCED, this event indicates that the
+     * state of this model has become 'stopped'.
+     *
+     * @param event A RecognitionEvent structure containing detailed results of the recognition
+     *     triggered
+     */
+    void phraseRecognitionCallback(in int model, in PhraseRecognitionEvent event);
+
+    /**
+     * Callback method called by the HAL when the sound recognition triggers.
+     * This event may only be delivered when the model state is 'started'.
+     * Unless the status of the event is RecognitionStatus.FORCED, this event indicates that the
+     * state of this model has become 'stopped'.
+     *
+     * @param event A RecognitionEvent structure containing detailed results of the recognition
+     *     triggered
+     */
+    void recognitionCallback(in int model, in RecognitionEvent event);
+}
diff --git a/soundtrigger/3/aidl/android/hardware/soundtrigger3/ISoundTriggerHwGlobalCallback.aidl b/soundtrigger/3/aidl/android/hardware/soundtrigger3/ISoundTriggerHwGlobalCallback.aidl
new file mode 100644
index 0000000..d6d8630
--- /dev/null
+++ b/soundtrigger/3/aidl/android/hardware/soundtrigger3/ISoundTriggerHwGlobalCallback.aidl
@@ -0,0 +1,34 @@
+/*
+ * Copyright 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 android.hardware.soundtrigger3;
+
+/**
+ * SoundTrigger HAL callback interface for events not associated with a particular model.
+ */
+@VintfStability
+interface ISoundTriggerHwGlobalCallback {
+    /**
+     * Callback method called by the HAL whenever internal conditions have been made available, such
+     * that a call that would previously have failed with an -EBUSY status may now succeed.
+     * There is no guarantee that any call would succeed following this event. It is merely a hint
+     * to the client that it may retry.
+     * Conversely, any call that have failed previously with a
+     * ServiceSpecificException(RESOURCE_CONTENTION) is guaranteed to fail again if retried, until
+     * this callback is delivered.
+     */
+    void onResourcesAvailable();
+}
diff --git a/soundtrigger/3/aidl_api/android.hardware.soundtrigger3/current/android/hardware/soundtrigger3/ISoundTriggerHw.aidl b/soundtrigger/3/aidl_api/android.hardware.soundtrigger3/current/android/hardware/soundtrigger3/ISoundTriggerHw.aidl
new file mode 100644
index 0000000..bbfe7d9
--- /dev/null
+++ b/soundtrigger/3/aidl_api/android.hardware.soundtrigger3/current/android/hardware/soundtrigger3/ISoundTriggerHw.aidl
@@ -0,0 +1,48 @@
+/*
+ * Copyright 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.
+ */
+///////////////////////////////////////////////////////////////////////////////
+// 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.soundtrigger3;
+@VintfStability
+interface ISoundTriggerHw {
+  android.media.soundtrigger.Properties getProperties();
+  void registerGlobalCallback(in android.hardware.soundtrigger3.ISoundTriggerHwGlobalCallback callback);
+  int loadSoundModel(in android.media.soundtrigger.SoundModel soundModel, in android.hardware.soundtrigger3.ISoundTriggerHwCallback callback);
+  int loadPhraseSoundModel(in android.media.soundtrigger.PhraseSoundModel soundModel, in android.hardware.soundtrigger3.ISoundTriggerHwCallback callback);
+  void unloadSoundModel(in int modelHandle);
+  void startRecognition(in int modelHandle, in int deviceHandle, in int ioHandle, in android.media.soundtrigger.RecognitionConfig config);
+  void stopRecognition(in int modelHandle);
+  void forceRecognitionEvent(in int modelHandle);
+  @nullable android.media.soundtrigger.ModelParameterRange queryParameter(in int modelHandle, in android.media.soundtrigger.ModelParameter modelParam);
+  int getParameter(in int modelHandle, in android.media.soundtrigger.ModelParameter modelParam);
+  void setParameter(in int modelHandle, in android.media.soundtrigger.ModelParameter modelParam, in int value);
+}
diff --git a/soundtrigger/3/aidl_api/android.hardware.soundtrigger3/current/android/hardware/soundtrigger3/ISoundTriggerHwCallback.aidl b/soundtrigger/3/aidl_api/android.hardware.soundtrigger3/current/android/hardware/soundtrigger3/ISoundTriggerHwCallback.aidl
new file mode 100644
index 0000000..152dfed
--- /dev/null
+++ b/soundtrigger/3/aidl_api/android.hardware.soundtrigger3/current/android/hardware/soundtrigger3/ISoundTriggerHwCallback.aidl
@@ -0,0 +1,40 @@
+/*
+ * Copyright 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.
+ */
+///////////////////////////////////////////////////////////////////////////////
+// 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.soundtrigger3;
+@VintfStability
+interface ISoundTriggerHwCallback {
+  void modelUnloaded(in int model);
+  void phraseRecognitionCallback(in int model, in android.media.soundtrigger.PhraseRecognitionEvent event);
+  void recognitionCallback(in int model, in android.media.soundtrigger.RecognitionEvent event);
+}
diff --git a/soundtrigger/3/aidl_api/android.hardware.soundtrigger3/current/android/hardware/soundtrigger3/ISoundTriggerHwGlobalCallback.aidl b/soundtrigger/3/aidl_api/android.hardware.soundtrigger3/current/android/hardware/soundtrigger3/ISoundTriggerHwGlobalCallback.aidl
new file mode 100644
index 0000000..6dfee9f
--- /dev/null
+++ b/soundtrigger/3/aidl_api/android.hardware.soundtrigger3/current/android/hardware/soundtrigger3/ISoundTriggerHwGlobalCallback.aidl
@@ -0,0 +1,38 @@
+/*
+ * Copyright 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.
+ */
+///////////////////////////////////////////////////////////////////////////////
+// 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.soundtrigger3;
+@VintfStability
+interface ISoundTriggerHwGlobalCallback {
+  void onResourcesAvailable();
+}