diff --git a/automotive/can/1.0/default/libnl++/Android.bp b/automotive/can/1.0/default/libnl++/Android.bp
index 790adcd..2ebd1b4 100644
--- a/automotive/can/1.0/default/libnl++/Android.bp
+++ b/automotive/can/1.0/default/libnl++/Android.bp
@@ -35,6 +35,7 @@
         "protocols/generic/Generic.cpp",
         "protocols/generic/GenericMessageBase.cpp",
         "protocols/generic/Unknown.cpp",
+        "protocols/generic/families/Mac80211hwsim.cpp",
         "protocols/generic/families/Nl80211.cpp",
         "protocols/route/Link.cpp",
         "protocols/route/Route.cpp",
@@ -42,6 +43,7 @@
         "protocols/MessageDefinition.cpp",
         "protocols/NetlinkProtocol.cpp",
         "protocols/all.cpp",
+        "protocols/structs.cpp",
         "Attributes.cpp",
         "MessageFactory.cpp",
         "MessageMutator.cpp",
diff --git a/automotive/can/1.0/default/libnl++/MessageMutator.cpp b/automotive/can/1.0/default/libnl++/MessageMutator.cpp
index 00b48a6..de2a2b1 100644
--- a/automotive/can/1.0/default/libnl++/MessageMutator.cpp
+++ b/automotive/can/1.0/default/libnl++/MessageMutator.cpp
@@ -19,7 +19,7 @@
 namespace android::nl {
 
 MessageMutator::MessageMutator(nlmsghdr* buffer, size_t totalLen)
-    : mConstBuffer(buffer, totalLen), mMutableBuffer(buffer) {
+    : mMutableBuffer(buffer), mTotalLen(totalLen) {
     CHECK(totalLen >= sizeof(nlmsghdr));
 }
 
@@ -27,8 +27,12 @@
     return mMutableBuffer;
 }
 
+Buffer<nlmsghdr> MessageMutator::constBuffer() const {
+    return {mMutableBuffer, mTotalLen};
+}
+
 MessageMutator::operator Buffer<nlmsghdr>() const {
-    return mConstBuffer;
+    return constBuffer();
 }
 
 uint64_t MessageMutator::read(Buffer<nlattr> attr) const {
@@ -37,7 +41,8 @@
 
 void MessageMutator::write(Buffer<nlattr> attr, uint64_t val) const {
     const auto attrData = attr.data<uint64_t>();
-    const auto offset = mConstBuffer.getOffset(attrData);
+    // TODO(b/177251183): deduplicate this code against fragment()
+    const auto offset = constBuffer().getOffset(attrData);
     CHECK(offset.has_value()) << "Trying to write attribute that's not a member of this message";
 
     const auto writeableBuffer = reinterpret_cast<uint8_t*>(mMutableBuffer) + *offset;
@@ -47,4 +52,40 @@
     memcpy(writeableBuffer, &val, std::min(sizeof(val), attrSize));
 }
 
+MessageMutator MessageMutator::fragment(Buffer<nlmsghdr> buf) const {
+    const auto offset = constBuffer().getOffset(buf);
+    CHECK(offset.has_value()) << "Trying to modify a fragment outside of buffer range";
+
+    const auto writeableBuffer = reinterpret_cast<nlmsghdr*>(uintptr_t(mMutableBuffer) + *offset);
+    const auto len = buf.getRaw().len();
+    CHECK(len <= mTotalLen - *offset);
+
+    return {writeableBuffer, len};
+}
+
+MessageMutator::iterator MessageMutator::begin() const {
+    return {*this, constBuffer().begin()};
+}
+
+MessageMutator::iterator MessageMutator::end() const {
+    return {*this, constBuffer().end()};
+}
+
+MessageMutator::iterator::iterator(const MessageMutator& container,
+                                   Buffer<nlmsghdr>::iterator current)
+    : mContainer(container), mCurrent(current) {}
+
+MessageMutator::iterator MessageMutator::iterator::operator++() {
+    ++mCurrent;
+    return *this;
+}
+
+bool MessageMutator::iterator::operator==(const iterator& other) const {
+    return other.mCurrent == mCurrent;
+}
+
+const MessageMutator MessageMutator::iterator::operator*() const {
+    return mContainer.fragment(*mCurrent);
+}
+
 }  // namespace android::nl
diff --git a/automotive/can/1.0/default/libnl++/include/libnl++/Buffer.h b/automotive/can/1.0/default/libnl++/include/libnl++/Buffer.h
index d759a0a..4cabb9a 100644
--- a/automotive/can/1.0/default/libnl++/include/libnl++/Buffer.h
+++ b/automotive/can/1.0/default/libnl++/include/libnl++/Buffer.h
@@ -138,7 +138,7 @@
     class raw_iterator : public iterator {
       public:
         iterator operator++() {
-            this->mCurrent.mData++;  // ignore alignment
+            ++this->mCurrent.mData;  // ignore alignment
             return *this;
         }
         const T& operator*() const { return *this->mCurrent.mData; }
diff --git a/automotive/can/1.0/default/libnl++/include/libnl++/Message.h b/automotive/can/1.0/default/libnl++/include/libnl++/Message.h
index 50b3c4b..29f397d 100644
--- a/automotive/can/1.0/default/libnl++/include/libnl++/Message.h
+++ b/automotive/can/1.0/default/libnl++/include/libnl++/Message.h
@@ -34,7 +34,7 @@
  * a single instance can only be used by a single thread - the one owning the underlying buffer).
  */
 template <typename T>
-class Message {
+class Message : public Buffer<nlmsghdr> {
   public:
     /**
      * Validate buffer contents as a message carrying T data and create instance of parsed message.
@@ -51,7 +51,7 @@
 
         const auto attributes = buf.data<nlattr>(sizeof(T));
 
-        return Message<T>(nlHeader, dataHeader, attributes);
+        return Message<T>(buf, nlHeader, dataHeader, attributes);
     }
 
     /**
@@ -94,8 +94,9 @@
     const T* operator->() const { return &data; }
 
   private:
-    Message(const nlmsghdr& nlHeader, const T& dataHeader, Attributes attributes)
-        : header(nlHeader), data(dataHeader), attributes(attributes) {}
+    Message(Buffer<nlmsghdr> buffer, const nlmsghdr& nlHeader, const T& dataHeader,
+            Attributes attributes)
+        : Buffer<nlmsghdr>(buffer), header(nlHeader), data(dataHeader), attributes(attributes) {}
 };
 
 }  // namespace android::nl
diff --git a/automotive/can/1.0/default/libnl++/include/libnl++/MessageMutator.h b/automotive/can/1.0/default/libnl++/include/libnl++/MessageMutator.h
index 7d495e9..baadc44 100644
--- a/automotive/can/1.0/default/libnl++/include/libnl++/MessageMutator.h
+++ b/automotive/can/1.0/default/libnl++/include/libnl++/MessageMutator.h
@@ -53,9 +53,27 @@
      */
     void write(Buffer<nlattr> attr, uint64_t val) const;
 
+    class iterator {
+      public:
+        iterator(const MessageMutator& container, Buffer<nlmsghdr>::iterator current);
+
+        iterator operator++();
+        bool operator==(const iterator& other) const;
+        const MessageMutator operator*() const;
+
+      protected:
+        const MessageMutator& mContainer;
+        Buffer<nlmsghdr>::iterator mCurrent;
+    };
+    iterator begin() const;
+    iterator end() const;
+
   private:
-    const Buffer<nlmsghdr> mConstBuffer;
     nlmsghdr* mMutableBuffer;
+    size_t mTotalLen;
+
+    Buffer<nlmsghdr> constBuffer() const;
+    MessageMutator fragment(Buffer<nlmsghdr> buf) const;
 };
 
 }  // namespace android::nl
diff --git a/automotive/can/1.0/default/libnl++/include/libnl++/generic/families/mac80211_hwsim.h b/automotive/can/1.0/default/libnl++/include/libnl++/generic/families/mac80211_hwsim.h
new file mode 100644
index 0000000..9b811f8
--- /dev/null
+++ b/automotive/can/1.0/default/libnl++/include/libnl++/generic/families/mac80211_hwsim.h
@@ -0,0 +1,73 @@
+/*
+ * Copyright (C) 2021 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+// API definitions from kernel drivers/net/wireless/mac80211_hwsim.h
+
+#define BIT(n) (1 << (n))
+
+enum hwsim_tx_control_flags {
+    HWSIM_TX_CTL_REQ_TX_STATUS = BIT(0),
+    HWSIM_TX_CTL_NO_ACK = BIT(1),
+    HWSIM_TX_STAT_ACK = BIT(2),
+};
+
+enum {
+    HWSIM_CMD_UNSPEC,
+    HWSIM_CMD_REGISTER,
+    HWSIM_CMD_FRAME,
+    HWSIM_CMD_TX_INFO_FRAME,
+    HWSIM_CMD_NEW_RADIO,
+    HWSIM_CMD_DEL_RADIO,
+    HWSIM_CMD_GET_RADIO,
+    HWSIM_CMD_ADD_MAC_ADDR,
+    HWSIM_CMD_DEL_MAC_ADDR,
+};
+
+enum {
+    HWSIM_ATTR_UNSPEC,
+    HWSIM_ATTR_ADDR_RECEIVER,
+    HWSIM_ATTR_ADDR_TRANSMITTER,
+    HWSIM_ATTR_FRAME,
+    HWSIM_ATTR_FLAGS,
+    HWSIM_ATTR_RX_RATE,
+    HWSIM_ATTR_SIGNAL,
+    HWSIM_ATTR_TX_INFO,
+    HWSIM_ATTR_COOKIE,
+    HWSIM_ATTR_CHANNELS,
+    HWSIM_ATTR_RADIO_ID,
+    HWSIM_ATTR_REG_HINT_ALPHA2,
+    HWSIM_ATTR_REG_CUSTOM_REG,
+    HWSIM_ATTR_REG_STRICT_REG,
+    HWSIM_ATTR_SUPPORT_P2P_DEVICE,
+    HWSIM_ATTR_USE_CHANCTX,
+    HWSIM_ATTR_DESTROY_RADIO_ON_CLOSE,
+    HWSIM_ATTR_RADIO_NAME,
+    HWSIM_ATTR_NO_VIF,
+    HWSIM_ATTR_FREQ,
+    HWSIM_ATTR_PAD,
+    HWSIM_ATTR_TX_INFO_FLAGS,
+    HWSIM_ATTR_PERM_ADDR,
+    HWSIM_ATTR_IFTYPE_SUPPORT,
+    HWSIM_ATTR_CIPHER_SUPPORT,
+};
+
+struct hwsim_tx_rate {
+    int8_t idx;
+    uint8_t count;
+} __packed;
+static_assert(sizeof(hwsim_tx_rate) == 2);
+
+#undef BIT
diff --git a/automotive/can/1.0/default/libnl++/printer.cpp b/automotive/can/1.0/default/libnl++/printer.cpp
index f08897e..d540482 100644
--- a/automotive/can/1.0/default/libnl++/printer.cpp
+++ b/automotive/can/1.0/default/libnl++/printer.cpp
@@ -154,16 +154,19 @@
     }
 }
 
-std::string toString(const Buffer<nlmsghdr> hdr, int protocol, bool printPayload) {
-    if (!hdr.firstOk()) return "nlmsg{buffer overflow}";
+static void toStream(std::stringstream& ss, const Buffer<nlmsghdr> hdr, int protocol,
+                     bool printPayload) {
+    if (!hdr.firstOk()) {
+        ss << "nlmsg{buffer overflow}";
+        return;
+    }
 
-    std::stringstream ss;
     ss << std::setfill('0');
 
     auto protocolMaybe = protocols::get(protocol);
     if (!protocolMaybe.has_value()) {
         ss << "nlmsg{protocol=" << protocol << "}";
-        return ss.str();
+        return;
     }
     protocols::NetlinkProtocol& protocolDescr = *protocolMaybe;
 
@@ -187,7 +190,7 @@
     ss << ", crc=" << std::hex << std::setw(4) << crc16(hdr.data<uint8_t>()) << std::dec;
     ss << '}';
 
-    if (!printPayload) return ss.str();
+    if (!printPayload) return;
     ss << ' ';
 
     if (!msgDescMaybe.has_value()) {
@@ -210,6 +213,17 @@
     }
 
     ss << "}";
+}
+
+std::string toString(const Buffer<nlmsghdr> hdrs, int protocol, bool printPayload) {
+    std::stringstream ss;
+    bool first = true;
+    for (const auto hdr : hdrs) {
+        if (!first) ss << std::endl;
+        first = false;
+
+        toStream(ss, hdr, protocol, printPayload);
+    }
 
     return ss.str();
 }
diff --git a/automotive/can/1.0/default/libnl++/protocols/generic/Ctrl.cpp b/automotive/can/1.0/default/libnl++/protocols/generic/Ctrl.cpp
index 1e1ad12..478c383 100644
--- a/automotive/can/1.0/default/libnl++/protocols/generic/Ctrl.cpp
+++ b/automotive/can/1.0/default/libnl++/protocols/generic/Ctrl.cpp
@@ -16,6 +16,7 @@
 
 #include "Ctrl.h"
 
+#include "families/Mac80211hwsim.h"
 #include "families/Nl80211.h"
 
 #include <libnl++/Message.h>
@@ -68,12 +69,15 @@
     const auto familyId = msg.attributes.get<uint16_t>(CTRL_ATTR_FAMILY_ID);
     const auto familyName = msg.attributes.get<std::string>(CTRL_ATTR_FAMILY_NAME);
 
-    /* For now, we support just a single family. But if you add more, please define proper
+    /* For now, we support just two families. But if you add more, please define proper
      * abstraction and not hardcode every name and class here.
      */
     if (familyName == "nl80211") {
         mFamilyRegister[familyId] = std::make_shared<families::Nl80211>(familyId);
     }
+    if (familyName == "MAC80211_HWSIM") {
+        mFamilyRegister[familyId] = std::make_shared<families::Mac80211hwsim>(familyId);
+    }
 }
 
 }  // namespace android::nl::protocols::generic
diff --git a/automotive/can/1.0/default/libnl++/protocols/generic/GenericMessageBase.cpp b/automotive/can/1.0/default/libnl++/protocols/generic/GenericMessageBase.cpp
index b7b811b..f92d6c0 100644
--- a/automotive/can/1.0/default/libnl++/protocols/generic/GenericMessageBase.cpp
+++ b/automotive/can/1.0/default/libnl++/protocols/generic/GenericMessageBase.cpp
@@ -40,9 +40,9 @@
 
     ss << "genlmsghdr{";
     if (commandName.has_value()) {
-        ss << "cmd=" << unsigned(data.cmd);
-    } else {
         ss << "cmd=" << *commandName;
+    } else {
+        ss << "cmd=" << unsigned(data.cmd);
     }
     ss << ", version=" << unsigned(data.version);
     if (data.reserved != 0) ss << ", reserved=" << data.reserved;
diff --git a/automotive/can/1.0/default/libnl++/protocols/generic/families/Mac80211hwsim.cpp b/automotive/can/1.0/default/libnl++/protocols/generic/families/Mac80211hwsim.cpp
new file mode 100644
index 0000000..f85309e
--- /dev/null
+++ b/automotive/can/1.0/default/libnl++/protocols/generic/families/Mac80211hwsim.cpp
@@ -0,0 +1,91 @@
+/*
+ * Copyright (C) 2021 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "Mac80211hwsim.h"
+
+#include "../../structs.h"
+#include "common.h"
+
+#include <libnl++/generic/families/mac80211_hwsim.h>
+
+namespace android::nl::protocols::generic::families {
+
+using DataType = AttributeDefinition::DataType;
+using Flags = AttributeDefinition::Flags;
+
+static void hwsim_tx_rateToStream(std::stringstream& ss, const Buffer<nlattr> attr);
+
+static const FlagsMap txControlFlags{
+        {HWSIM_TX_CTL_REQ_TX_STATUS, "REQ_TX"},
+        {HWSIM_TX_CTL_NO_ACK, "NO_ACK"},
+        {HWSIM_TX_STAT_ACK, "ACK"},
+};
+
+// clang-format off
+Mac80211hwsim::Mac80211hwsim(nlmsgtype_t familyId) : GenericMessageBase(familyId, "hwsim", {
+    {HWSIM_CMD_UNSPEC, "UNSPEC"},
+    {HWSIM_CMD_REGISTER, "REGISTER"},
+    {HWSIM_CMD_FRAME, "FRAME"},
+    {HWSIM_CMD_TX_INFO_FRAME, "TX_INFO_FRAME"},
+    {HWSIM_CMD_NEW_RADIO, "NEW_RADIO"},
+    {HWSIM_CMD_DEL_RADIO, "DEL_RADIO"},
+    {HWSIM_CMD_GET_RADIO, "GET_RADIO"},
+    {HWSIM_CMD_ADD_MAC_ADDR, "ADD_MAC_ADDR"},
+    {HWSIM_CMD_DEL_MAC_ADDR, "DEL_MAC_ADDR"},
+}, {
+    {HWSIM_ATTR_UNSPEC, {"UNSPEC"}},
+    {HWSIM_ATTR_ADDR_RECEIVER, {"ADDR_RECEIVER", DataType::Struct, hwaddrToStream}},
+    {HWSIM_ATTR_ADDR_TRANSMITTER, {"ADDR_TRANSMITTER", DataType::Struct, hwaddrToStream}},
+    {HWSIM_ATTR_FRAME, {"FRAME", DataType::Raw, AttributeMap{}, Flags::Verbose}},
+    {HWSIM_ATTR_FLAGS, {"FLAGS", DataType::Struct, flagsToStream(txControlFlags)}},
+    {HWSIM_ATTR_RX_RATE, {"RX_RATE", DataType::Uint}},
+    {HWSIM_ATTR_SIGNAL, {"SIGNAL", DataType::Uint}},
+    {HWSIM_ATTR_TX_INFO, {"TX_INFO", DataType::Struct, hwsim_tx_rateToStream}},
+    {HWSIM_ATTR_COOKIE, {"COOKIE", DataType::Uint}},
+    {HWSIM_ATTR_CHANNELS, {"CHANNELS", DataType::Uint}},
+    {HWSIM_ATTR_RADIO_ID, {"RADIO_ID", DataType::Uint}},
+    {HWSIM_ATTR_REG_HINT_ALPHA2, {"REG_HINT_ALPHA2", DataType::String}},
+    {HWSIM_ATTR_REG_CUSTOM_REG, {"REG_CUSTOM_REG", DataType::Uint}},
+    {HWSIM_ATTR_REG_STRICT_REG, {"REG_STRICT_REG", DataType::Flag}},
+    {HWSIM_ATTR_SUPPORT_P2P_DEVICE, {"SUPPORT_P2P_DEVICE", DataType::Flag}},
+    {HWSIM_ATTR_USE_CHANCTX, {"USE_CHANCTX", DataType::Flag}},
+    {HWSIM_ATTR_DESTROY_RADIO_ON_CLOSE, {"DESTROY_RADIO_ON_CLOSE", DataType::Flag}},
+    {HWSIM_ATTR_RADIO_NAME, {"RADIO_NAME", DataType::String}},
+    {HWSIM_ATTR_NO_VIF, {"NO_VIF", DataType::Flag}},
+    {HWSIM_ATTR_FREQ, {"FREQ", DataType::Uint}},
+    {HWSIM_ATTR_PAD, {"PAD", DataType::Uint}},
+    {HWSIM_ATTR_TX_INFO_FLAGS, {"TX_INFO_FLAGS"}},  // hwsim_tx_rate_flag
+    {HWSIM_ATTR_PERM_ADDR, {"PERM_ADDR"}},
+    {HWSIM_ATTR_IFTYPE_SUPPORT, {"IFTYPE_SUPPORT", DataType::Uint}},  // NL80211_IFTYPE_STATION etc
+    {HWSIM_ATTR_CIPHER_SUPPORT, {"CIPHER_SUPPORT", DataType::Struct, arrayToStream<int32_t>}},
+}) {}
+// clang-format on
+
+static void hwsim_tx_rateToStream(std::stringstream& ss, const Buffer<nlattr> attr) {
+    ss << '{';
+    bool first = true;
+    for (const auto rate : attr.data<hwsim_tx_rate>().getRaw()) {
+        if (rate.idx == -1) continue;
+
+        ss << (int)rate.idx << ": " << (unsigned)rate.count;
+
+        if (!first) ss << ", ";
+        first = false;
+    }
+    ss << '}';
+}
+
+}  // namespace android::nl::protocols::generic::families
diff --git a/automotive/can/1.0/default/libnl++/protocols/generic/families/Mac80211hwsim.h b/automotive/can/1.0/default/libnl++/protocols/generic/families/Mac80211hwsim.h
new file mode 100644
index 0000000..c01eb93
--- /dev/null
+++ b/automotive/can/1.0/default/libnl++/protocols/generic/families/Mac80211hwsim.h
@@ -0,0 +1,28 @@
+/*
+ * Copyright (C) 2021 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include "../GenericMessageBase.h"
+
+namespace android::nl::protocols::generic::families {
+
+class Mac80211hwsim : public GenericMessageBase {
+  public:
+    Mac80211hwsim(nlmsgtype_t familyId);
+};
+
+}  // namespace android::nl::protocols::generic::families
diff --git a/automotive/can/1.0/default/libnl++/protocols/structs.cpp b/automotive/can/1.0/default/libnl++/protocols/structs.cpp
new file mode 100644
index 0000000..8ff71f0
--- /dev/null
+++ b/automotive/can/1.0/default/libnl++/protocols/structs.cpp
@@ -0,0 +1,57 @@
+/*
+ * Copyright (C) 2021 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "structs.h"
+
+#include <iomanip>
+
+namespace android::nl::protocols {
+
+AttributeDefinition::ToStream flagsToStream(FlagsMap flags) {
+    return [flags](std::stringstream& ss, const Buffer<nlattr> attr) {
+        auto val = attr.data<uint64_t>().copyFirst();
+
+        bool first = true;
+        for (const auto& [flag, name] : flags) {
+            if ((val & flag) != flag) continue;
+            val &= ~flag;
+
+            if (!first) ss << '|';
+            first = false;
+
+            ss << name;
+        }
+
+        if (val == 0) return;
+
+        if (!first) ss << '|';
+        ss << std::hex << val << std::dec;
+    };
+}
+
+void hwaddrToStream(std::stringstream& ss, const Buffer<nlattr> attr) {
+    ss << std::hex;
+    bool first = true;
+    for (const auto byte : attr.data<uint8_t>().getRaw()) {
+        if (!first) ss << ':';
+        first = false;
+
+        ss << std::setw(2) << unsigned(byte);
+    }
+    ss << std::dec;
+}
+
+}  // namespace android::nl::protocols
diff --git a/automotive/can/1.0/default/libnl++/protocols/structs.h b/automotive/can/1.0/default/libnl++/protocols/structs.h
index 44c17b8..f3a8c44 100644
--- a/automotive/can/1.0/default/libnl++/protocols/structs.h
+++ b/automotive/can/1.0/default/libnl++/protocols/structs.h
@@ -16,6 +16,8 @@
 
 #pragma once
 
+#include "MessageDefinition.h"
+
 #include <sstream>
 
 namespace android::nl::protocols {
@@ -30,4 +32,9 @@
     ss << '}';
 }
 
+typedef std::map<uint64_t, std::string> FlagsMap;
+AttributeDefinition::ToStream flagsToStream(FlagsMap flags);
+
+void hwaddrToStream(std::stringstream& ss, const Buffer<nlattr> attr);
+
 }  // namespace android::nl::protocols
diff --git a/common/aidl/aidl_api/android.hardware.common/current/android/hardware/common/Ashmem.aidl b/common/aidl/aidl_api/android.hardware.common/current/android/hardware/common/Ashmem.aidl
new file mode 100644
index 0000000..a438031
--- /dev/null
+++ b/common/aidl/aidl_api/android.hardware.common/current/android/hardware/common/Ashmem.aidl
@@ -0,0 +1,39 @@
+/*
+ * 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.common;
+@VintfStability
+parcelable Ashmem {
+  ParcelFileDescriptor fd;
+  long size;
+}
diff --git a/common/aidl/aidl_api/android.hardware.common/current/android/hardware/common/MappableFile.aidl b/common/aidl/aidl_api/android.hardware.common/current/android/hardware/common/MappableFile.aidl
new file mode 100644
index 0000000..394ea8f
--- /dev/null
+++ b/common/aidl/aidl_api/android.hardware.common/current/android/hardware/common/MappableFile.aidl
@@ -0,0 +1,41 @@
+/*
+ * 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.common;
+@VintfStability
+parcelable MappableFile {
+  long length;
+  int prot;
+  ParcelFileDescriptor fd;
+  long offset;
+}
diff --git a/common/aidl/aidl_api/android.hardware.common/current/android/hardware/common/NativeHandle.aidl b/common/aidl/aidl_api/android.hardware.common/current/android/hardware/common/NativeHandle.aidl
index f37b7d5..2ed5c0b 100644
--- a/common/aidl/aidl_api/android.hardware.common/current/android/hardware/common/NativeHandle.aidl
+++ b/common/aidl/aidl_api/android.hardware.common/current/android/hardware/common/NativeHandle.aidl
@@ -1,14 +1,30 @@
+/*
+ * Copyright 2019 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 interface (or parcelable). Do not try to
-// edit this file. It looks like you are doing that because you have modified
-// an AIDL interface in a backward-incompatible way, e.g., deleting a function
-// from an interface or a field from a parcelable and it broke the build. That
-// breakage is intended.
+// 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 changes to the AIDL files built
+// 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
diff --git a/common/aidl/android/hardware/common/Ashmem.aidl b/common/aidl/android/hardware/common/Ashmem.aidl
new file mode 100644
index 0000000..8e40266
--- /dev/null
+++ b/common/aidl/android/hardware/common/Ashmem.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.common;
+
+import android.os.ParcelFileDescriptor;
+
+/**
+ * Type that holds same memory as the "ashmem" hidl_memory type from HIDL.
+ */
+@VintfStability
+parcelable Ashmem {
+    /**
+     * A handle to a memory region.
+     */
+    ParcelFileDescriptor fd;
+    /**
+     * Size of the memory region in bytes.
+     */
+    long size;
+}
diff --git a/common/aidl/android/hardware/common/MappableFile.aidl b/common/aidl/android/hardware/common/MappableFile.aidl
new file mode 100644
index 0000000..a7763ea
--- /dev/null
+++ b/common/aidl/android/hardware/common/MappableFile.aidl
@@ -0,0 +1,53 @@
+/*
+ * 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.common;
+
+import android.os.ParcelFileDescriptor;
+
+/**
+ * A region of a file that can be mapped into memory.
+ *
+ * In Linux, MappableFile may be used with mmap as `MAP_SHARED`.
+ *
+ * MappableFile is compatible with ::android::base::MappedFile.
+ */
+@VintfStability
+parcelable MappableFile {
+    /**
+     * Length of the mapping region in bytes.
+     */
+    long length;
+    /**
+     * The desired memory protection for the mapping.
+     *
+     * In Linux, prot is either `PROT_NONE` (indicating that mapped pages may not be accessed) or
+     * the bitwise OR of one or more of the following flags:
+     * - `PROT_READ` (indicating that the mapped pages may be read)
+     * - `PROT_WRITE` (indicating that the mapped pages may be written)
+     */
+    int prot;
+    /**
+     * A handle to a mappable file.
+     */
+    ParcelFileDescriptor fd;
+    /**
+     * The offset in the file to the beginning of the mapping region in number of bytes.
+     *
+     * Note: Some mapping functions require that the offset is aligned to the page size.
+     */
+    long offset;
+}
diff --git a/common/support/Android.bp b/common/support/Android.bp
index 8aea306..730798d 100644
--- a/common/support/Android.bp
+++ b/common/support/Android.bp
@@ -18,6 +18,11 @@
         "android.hardware.common-V2-ndk_platform",
         "libcutils",
     ],
+    apex_available: [
+        "//apex_available:platform",
+        "com.android.neuralnetworks",
+    ],
+    min_sdk_version: "29",
 }
 
 cc_test {
diff --git a/compatibility_matrices/compatibility_matrix.current.xml b/compatibility_matrices/compatibility_matrix.current.xml
index bb22974..7f9186f 100644
--- a/compatibility_matrices/compatibility_matrix.current.xml
+++ b/compatibility_matrices/compatibility_matrix.current.xml
@@ -90,7 +90,7 @@
         <version>2.0</version>
         <interface>
             <name>IVehicle</name>
-            <instance>default</instance>
+            <regex-instance>.*</regex-instance>
         </interface>
     </hal>
     <hal format="hidl" optional="true">
@@ -521,12 +521,20 @@
     </hal>
     <hal format="hidl" optional="true">
         <name>android.hardware.soundtrigger</name>
-        <version>2.3</version>
+        <version>2.3-4</version>
         <interface>
             <name>ISoundTriggerHw</name>
             <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/graphics/common/aidl/Android.bp b/graphics/common/aidl/Android.bp
index 2a46f9d..cadd13c 100644
--- a/graphics/common/aidl/Android.bp
+++ b/graphics/common/aidl/Android.bp
@@ -34,6 +34,7 @@
             apex_available: [
                 "//apex_available:platform",
                 "com.android.media.swcodec",
+                "com.android.neuralnetworks",
             ],
             min_sdk_version: "29",
         },
diff --git a/neuralnetworks/aidl/Android.bp b/neuralnetworks/aidl/Android.bp
index b1860e2..ebf4654 100644
--- a/neuralnetworks/aidl/Android.bp
+++ b/neuralnetworks/aidl/Android.bp
@@ -16,6 +16,7 @@
     stability: "vintf",
     imports: [
         "android.hardware.common",
+        "android.hardware.graphics.common",
     ],
     backend: {
         java: {
diff --git a/neuralnetworks/aidl/aidl_api/android.hardware.neuralnetworks/current/android/hardware/neuralnetworks/Memory.aidl b/neuralnetworks/aidl/aidl_api/android.hardware.neuralnetworks/current/android/hardware/neuralnetworks/Memory.aidl
index 8207b25..37fa102 100644
--- a/neuralnetworks/aidl/aidl_api/android.hardware.neuralnetworks/current/android/hardware/neuralnetworks/Memory.aidl
+++ b/neuralnetworks/aidl/aidl_api/android.hardware.neuralnetworks/current/android/hardware/neuralnetworks/Memory.aidl
@@ -33,8 +33,8 @@
 
 package android.hardware.neuralnetworks;
 @VintfStability
-parcelable Memory {
-  android.hardware.common.NativeHandle handle;
-  long size;
-  String name;
+union Memory {
+  android.hardware.common.Ashmem ashmem;
+  android.hardware.common.MappableFile mappableFile;
+  android.hardware.graphics.common.HardwareBuffer hardwareBuffer;
 }
diff --git a/neuralnetworks/aidl/android/hardware/neuralnetworks/Memory.aidl b/neuralnetworks/aidl/android/hardware/neuralnetworks/Memory.aidl
index 870f0ae..244ac87 100644
--- a/neuralnetworks/aidl/android/hardware/neuralnetworks/Memory.aidl
+++ b/neuralnetworks/aidl/android/hardware/neuralnetworks/Memory.aidl
@@ -15,16 +15,26 @@
  */
 
 package android.hardware.neuralnetworks;
-import android.hardware.common.NativeHandle;
-import android.os.ParcelFileDescriptor;
+
+import android.hardware.common.Ashmem;
+import android.hardware.common.MappableFile;
+import android.hardware.graphics.common.HardwareBuffer;
 
 /**
- * A type that is used to pass pieces of shared memory between processes.
- * The type structure mimics hidl_memory type from HIDL.
+ * The different types of memory that can be shared across processes.
  */
 @VintfStability
-parcelable Memory {
-    NativeHandle handle;
-    long size;
-    String name;
+union Memory {
+    /**
+     * Ashmem hidl_memory type from HIDL.
+     */
+    Ashmem ashmem;
+    /**
+     * File that can be mapped.
+     */
+    MappableFile mappableFile;
+    /**
+     * AIDL representation of AHardwareBuffer.
+     */
+    HardwareBuffer hardwareBuffer;
 }
diff --git a/neuralnetworks/aidl/utils/Android.bp b/neuralnetworks/aidl/utils/Android.bp
index ad961cf..0ccc711 100644
--- a/neuralnetworks/aidl/utils/Android.bp
+++ b/neuralnetworks/aidl/utils/Android.bp
@@ -31,6 +31,8 @@
     export_include_dirs: ["include"],
     cflags: ["-Wthread-safety"],
     static_libs: [
+        "android.hardware.graphics.common-V2-ndk_platform",
+        "libaidlcommonsupport",
         "libarect",
         "neuralnetworks_types",
         "neuralnetworks_utils_hal_common",
@@ -51,7 +53,9 @@
     ],
     static_libs: [
         "android.hardware.common-V2-ndk_platform",
+        "android.hardware.graphics.common-V2-ndk_platform",
         "android.hardware.neuralnetworks-V1-ndk_platform",
+        "libaidlcommonsupport",
         "libgmock",
         "libneuralnetworks_common",
         "neuralnetworks_types",
diff --git a/neuralnetworks/aidl/utils/src/Conversions.cpp b/neuralnetworks/aidl/utils/src/Conversions.cpp
index d5f7f81..93ac51c 100644
--- a/neuralnetworks/aidl/utils/src/Conversions.cpp
+++ b/neuralnetworks/aidl/utils/src/Conversions.cpp
@@ -16,8 +16,13 @@
 
 #include "Conversions.h"
 
+#include <aidl/android/hardware/common/Ashmem.h>
+#include <aidl/android/hardware/common/MappableFile.h>
 #include <aidl/android/hardware/common/NativeHandle.h>
+#include <aidl/android/hardware/graphics/common/HardwareBuffer.h>
+#include <aidlcommonsupport/NativeHandle.h>
 #include <android-base/logging.h>
+#include <android-base/mapped_file.h>
 #include <android-base/unique_fd.h>
 #include <android/binder_auto_utils.h>
 #include <android/hardware_buffer.h>
@@ -125,28 +130,17 @@
 
 using UniqueNativeHandle = std::unique_ptr<native_handle_t, NativeHandleDeleter>;
 
-static GeneralResult<UniqueNativeHandle> nativeHandleFromAidlHandle(const NativeHandle& handle) {
-    std::vector<base::unique_fd> fds;
-    fds.reserve(handle.fds.size());
-    for (const auto& fd : handle.fds) {
-        auto duplicatedFd = NN_TRY(dupFd(fd.get()));
-        fds.emplace_back(duplicatedFd.release());
+GeneralResult<UniqueNativeHandle> nativeHandleFromAidlHandle(const NativeHandle& handle) {
+    auto nativeHandle = UniqueNativeHandle(dupFromAidl(handle));
+    if (nativeHandle.get() == nullptr) {
+        return NN_ERROR() << "android::dupFromAidl failed to convert the common::NativeHandle to a "
+                             "native_handle_t";
     }
-
-    constexpr size_t kIntMax = std::numeric_limits<int>::max();
-    CHECK_LE(handle.fds.size(), kIntMax);
-    CHECK_LE(handle.ints.size(), kIntMax);
-    native_handle_t* nativeHandle = native_handle_create(static_cast<int>(handle.fds.size()),
-                                                         static_cast<int>(handle.ints.size()));
-    if (nativeHandle == nullptr) {
-        return NN_ERROR() << "Failed to create native_handle";
+    if (!std::all_of(nativeHandle->data + 0, nativeHandle->data + nativeHandle->numFds,
+                     [](int fd) { return fd >= 0; })) {
+        return NN_ERROR() << "android::dupFromAidl returned an invalid native_handle_t";
     }
-    for (size_t i = 0; i < fds.size(); ++i) {
-        nativeHandle->data[i] = fds[i].release();
-    }
-    std::copy(handle.ints.begin(), handle.ints.end(), &nativeHandle->data[nativeHandle->numFds]);
-
-    return UniqueNativeHandle(nativeHandle);
+    return nativeHandle;
 }
 
 }  // anonymous namespace
@@ -353,67 +347,66 @@
     return measureTiming ? MeasureTiming::YES : MeasureTiming::NO;
 }
 
-static uint32_t roundUpToMultiple(uint32_t value, uint32_t multiple) {
-    return (value + multiple - 1) / multiple * multiple;
-}
-
 GeneralResult<SharedMemory> unvalidatedConvert(const aidl_hal::Memory& memory) {
-    VERIFY_NON_NEGATIVE(memory.size) << "Memory size must not be negative";
-    if (memory.size > std::numeric_limits<size_t>::max()) {
-        return NN_ERROR() << "Memory: size must be <= std::numeric_limits<size_t>::max()";
-    }
+    using Tag = aidl_hal::Memory::Tag;
+    switch (memory.getTag()) {
+        case Tag::ashmem: {
+            const auto& ashmem = memory.get<Tag::ashmem>();
+            VERIFY_NON_NEGATIVE(ashmem.size) << "Memory size must not be negative";
+            if (ashmem.size > std::numeric_limits<size_t>::max()) {
+                return NN_ERROR() << "Memory: size must be <= std::numeric_limits<size_t>::max()";
+            }
 
-    if (memory.name != "hardware_buffer_blob") {
-        return std::make_shared<const Memory>(Memory{
-                .handle = NN_TRY(unvalidatedConvertHelper(memory.handle)),
-                .size = static_cast<size_t>(memory.size),
-                .name = memory.name,
-        });
-    }
+            auto handle = Memory::Ashmem{
+                    .fd = NN_TRY(dupFd(ashmem.fd.get())),
+                    .size = static_cast<size_t>(ashmem.size),
+            };
+            return std::make_shared<const Memory>(Memory{.handle = std::move(handle)});
+        }
+        case Tag::mappableFile: {
+            const auto& mappableFile = memory.get<Tag::mappableFile>();
+            VERIFY_NON_NEGATIVE(mappableFile.length) << "Memory size must not be negative";
+            VERIFY_NON_NEGATIVE(mappableFile.offset) << "Memory offset must not be negative";
+            if (mappableFile.length > std::numeric_limits<size_t>::max()) {
+                return NN_ERROR() << "Memory: size must be <= std::numeric_limits<size_t>::max()";
+            }
+            if (mappableFile.offset > std::numeric_limits<size_t>::max()) {
+                return NN_ERROR() << "Memory: offset must be <= std::numeric_limits<size_t>::max()";
+            }
 
-    const auto size = static_cast<uint32_t>(memory.size);
-    const auto format = AHARDWAREBUFFER_FORMAT_BLOB;
-    const auto usage = AHARDWAREBUFFER_USAGE_CPU_READ_OFTEN | AHARDWAREBUFFER_USAGE_CPU_WRITE_OFTEN;
-    const uint32_t width = size;
-    const uint32_t height = 1;  // height is always 1 for BLOB mode AHardwareBuffer.
-    const uint32_t layers = 1;  // layers is always 1 for BLOB mode AHardwareBuffer.
+            const size_t size = static_cast<size_t>(mappableFile.length);
+            const int prot = mappableFile.prot;
+            const int fd = mappableFile.fd.get();
+            const size_t offset = static_cast<size_t>(mappableFile.offset);
 
-    const UniqueNativeHandle handle = NN_TRY(nativeHandleFromAidlHandle(memory.handle));
-    const native_handle_t* nativeHandle = handle.get();
+            return createSharedMemoryFromFd(size, prot, fd, offset);
+        }
+        case Tag::hardwareBuffer: {
+            const auto& hardwareBuffer = memory.get<Tag::hardwareBuffer>();
 
-    // AHardwareBuffer_createFromHandle() might fail because an allocator
-    // expects a specific stride value. In that case, we try to guess it by
-    // aligning the width to small powers of 2.
-    // TODO(b/174120849): Avoid stride assumptions.
-    AHardwareBuffer* hardwareBuffer = nullptr;
-    status_t status = UNKNOWN_ERROR;
-    for (uint32_t alignment : {1, 4, 32, 64, 128, 2, 8, 16}) {
-        const uint32_t stride = roundUpToMultiple(width, alignment);
-        AHardwareBuffer_Desc desc{
-                .width = width,
-                .height = height,
-                .layers = layers,
-                .format = format,
-                .usage = usage,
-                .stride = stride,
-        };
-        status = AHardwareBuffer_createFromHandle(&desc, nativeHandle,
-                                                  AHARDWAREBUFFER_CREATE_FROM_HANDLE_METHOD_CLONE,
-                                                  &hardwareBuffer);
-        if (status == NO_ERROR) {
-            break;
+            const UniqueNativeHandle handle =
+                    NN_TRY(nativeHandleFromAidlHandle(hardwareBuffer.handle));
+            const native_handle_t* nativeHandle = handle.get();
+
+            const AHardwareBuffer_Desc desc{
+                    .width = static_cast<uint32_t>(hardwareBuffer.description.width),
+                    .height = static_cast<uint32_t>(hardwareBuffer.description.height),
+                    .layers = static_cast<uint32_t>(hardwareBuffer.description.layers),
+                    .format = static_cast<uint32_t>(hardwareBuffer.description.format),
+                    .usage = static_cast<uint64_t>(hardwareBuffer.description.usage),
+                    .stride = static_cast<uint32_t>(hardwareBuffer.description.stride),
+            };
+            AHardwareBuffer* ahwb = nullptr;
+            const status_t status = AHardwareBuffer_createFromHandle(
+                    &desc, nativeHandle, AHARDWAREBUFFER_CREATE_FROM_HANDLE_METHOD_CLONE, &ahwb);
+            if (status != NO_ERROR) {
+                return NN_ERROR() << "createFromHandle failed";
+            }
+
+            return createSharedMemoryFromAHWB(ahwb, /*takeOwnership=*/true);
         }
     }
-    if (status != NO_ERROR) {
-        return NN_ERROR(ErrorStatus::GENERAL_FAILURE)
-               << "Can't create AHardwareBuffer from handle. Error: " << status;
-    }
-
-    return std::make_shared<const Memory>(Memory{
-            .handle = HardwareBufferHandle(hardwareBuffer, /*takeOwnership=*/true),
-            .size = static_cast<size_t>(memory.size),
-            .name = memory.name,
-    });
+    return NN_ERROR() << "Unrecognized Memory::Tag: " << memory.getTag();
 }
 
 GeneralResult<Timing> unvalidatedConvert(const aidl_hal::Timing& timing) {
@@ -645,20 +638,95 @@
 template <class... Ts>
 overloaded(Ts...)->overloaded<Ts...>;
 
-static nn::GeneralResult<common::NativeHandle> aidlHandleFromNativeHandle(
-        const native_handle_t& handle) {
-    common::NativeHandle aidlNativeHandle;
+nn::GeneralResult<common::NativeHandle> aidlHandleFromNativeHandle(
+        const native_handle_t& nativeHandle) {
+    auto handle = ::android::dupToAidl(&nativeHandle);
+    if (!std::all_of(handle.fds.begin(), handle.fds.end(),
+                     [](const ndk::ScopedFileDescriptor& fd) { return fd.get() >= 0; })) {
+        return NN_ERROR() << "android::dupToAidl returned an invalid common::NativeHandle";
+    }
+    return handle;
+}
 
-    aidlNativeHandle.fds.reserve(handle.numFds);
-    for (int i = 0; i < handle.numFds; ++i) {
-        auto duplicatedFd = NN_TRY(nn::dupFd(handle.data[i]));
-        aidlNativeHandle.fds.emplace_back(duplicatedFd.release());
+nn::GeneralResult<Memory> unvalidatedConvert(const nn::Memory::Ashmem& memory) {
+    if constexpr (std::numeric_limits<size_t>::max() > std::numeric_limits<int64_t>::max()) {
+        if (memory.size > std::numeric_limits<int64_t>::max()) {
+            return (
+                           NN_ERROR()
+                           << "Memory::Ashmem: size must be <= std::numeric_limits<int64_t>::max()")
+                    .
+                    operator nn::GeneralResult<Memory>();
+        }
     }
 
-    aidlNativeHandle.ints = std::vector<int>(&handle.data[handle.numFds],
-                                             &handle.data[handle.numFds + handle.numInts]);
+    auto fd = NN_TRY(nn::dupFd(memory.fd));
+    auto handle = common::Ashmem{
+            .fd = ndk::ScopedFileDescriptor(fd.release()),
+            .size = static_cast<int64_t>(memory.size),
+    };
+    return Memory::make<Memory::Tag::ashmem>(std::move(handle));
+}
 
-    return aidlNativeHandle;
+nn::GeneralResult<Memory> unvalidatedConvert(const nn::Memory::Fd& memory) {
+    if constexpr (std::numeric_limits<size_t>::max() > std::numeric_limits<int64_t>::max()) {
+        if (memory.size > std::numeric_limits<int64_t>::max()) {
+            return (NN_ERROR() << "Memory::Fd: size must be <= std::numeric_limits<int64_t>::max()")
+                    .
+                    operator nn::GeneralResult<Memory>();
+        }
+        if (memory.offset > std::numeric_limits<int64_t>::max()) {
+            return (
+                           NN_ERROR()
+                           << "Memory::Fd: offset must be <= std::numeric_limits<int64_t>::max()")
+                    .
+                    operator nn::GeneralResult<Memory>();
+        }
+    }
+
+    auto fd = NN_TRY(nn::dupFd(memory.fd));
+    auto handle = common::MappableFile{
+            .length = static_cast<int64_t>(memory.size),
+            .prot = memory.prot,
+            .fd = ndk::ScopedFileDescriptor(fd.release()),
+            .offset = static_cast<int64_t>(memory.offset),
+    };
+    return Memory::make<Memory::Tag::mappableFile>(std::move(handle));
+}
+
+nn::GeneralResult<Memory> unvalidatedConvert(const nn::Memory::HardwareBuffer& memory) {
+    const native_handle_t* nativeHandle = AHardwareBuffer_getNativeHandle(memory.handle.get());
+    if (nativeHandle == nullptr) {
+        return (NN_ERROR() << "unvalidatedConvert failed because AHardwareBuffer_getNativeHandle "
+                              "returned nullptr")
+                .
+                operator nn::GeneralResult<Memory>();
+    }
+
+    auto handle = NN_TRY(aidlHandleFromNativeHandle(*nativeHandle));
+
+    AHardwareBuffer_Desc desc;
+    AHardwareBuffer_describe(memory.handle.get(), &desc);
+
+    const auto description = graphics::common::HardwareBufferDescription{
+            .width = static_cast<int32_t>(desc.width),
+            .height = static_cast<int32_t>(desc.height),
+            .layers = static_cast<int32_t>(desc.layers),
+            .format = static_cast<graphics::common::PixelFormat>(desc.format),
+            .usage = static_cast<graphics::common::BufferUsage>(desc.usage),
+            .stride = static_cast<int32_t>(desc.stride),
+    };
+
+    auto hardwareBuffer = graphics::common::HardwareBuffer{
+            .description = std::move(description),
+            .handle = std::move(handle),
+    };
+    return Memory::make<Memory::Tag::hardwareBuffer>(std::move(hardwareBuffer));
+}
+
+nn::GeneralResult<Memory> unvalidatedConvert(const nn::Memory::Unknown& /*memory*/) {
+    return (NN_ERROR() << "Unable to convert Unknown memory type")
+            .
+            operator nn::GeneralResult<Memory>();
 }
 
 }  // namespace
@@ -693,41 +761,12 @@
 }
 
 nn::GeneralResult<Memory> unvalidatedConvert(const nn::SharedMemory& memory) {
-    CHECK(memory != nullptr);
-    if (memory->size > std::numeric_limits<int64_t>::max()) {
-        return NN_ERROR() << "Memory size doesn't fit into int64_t.";
+    if (memory == nullptr) {
+        return (NN_ERROR() << "Unable to convert nullptr memory")
+                .
+                operator nn::GeneralResult<Memory>();
     }
-    if (const auto* handle = std::get_if<nn::Handle>(&memory->handle)) {
-        return Memory{
-                .handle = NN_TRY(unvalidatedConvert(*handle)),
-                .size = static_cast<int64_t>(memory->size),
-                .name = memory->name,
-        };
-    }
-
-    const auto* ahwb = std::get<nn::HardwareBufferHandle>(memory->handle).get();
-    AHardwareBuffer_Desc bufferDesc;
-    AHardwareBuffer_describe(ahwb, &bufferDesc);
-
-    if (bufferDesc.format == AHARDWAREBUFFER_FORMAT_BLOB) {
-        CHECK_EQ(memory->size, bufferDesc.width);
-        CHECK_EQ(memory->name, "hardware_buffer_blob");
-    } else {
-        CHECK_EQ(memory->size, 0u);
-        CHECK_EQ(memory->name, "hardware_buffer");
-    }
-
-    const native_handle_t* nativeHandle = AHardwareBuffer_getNativeHandle(ahwb);
-    if (nativeHandle == nullptr) {
-        return NN_ERROR() << "unvalidatedConvert failed because AHardwareBuffer_getNativeHandle "
-                             "returned nullptr";
-    }
-
-    return Memory{
-            .handle = NN_TRY(aidlHandleFromNativeHandle(*nativeHandle)),
-            .size = static_cast<int64_t>(memory->size),
-            .name = memory->name,
-    };
+    return std::visit([](const auto& x) { return unvalidatedConvert(x); }, memory->handle);
 }
 
 nn::GeneralResult<ErrorStatus> unvalidatedConvert(const nn::ErrorStatus& errorStatus) {
diff --git a/neuralnetworks/aidl/utils/src/Utils.cpp b/neuralnetworks/aidl/utils/src/Utils.cpp
index 95516c8..03407be 100644
--- a/neuralnetworks/aidl/utils/src/Utils.cpp
+++ b/neuralnetworks/aidl/utils/src/Utils.cpp
@@ -16,12 +16,20 @@
 
 #include "Utils.h"
 
+#include <aidl/android/hardware/common/Ashmem.h>
+#include <aidl/android/hardware/common/MappableFile.h>
+#include <aidl/android/hardware/graphics/common/HardwareBuffer.h>
+#include <android/binder_auto_utils.h>
 #include <android/binder_status.h>
 #include <nnapi/Result.h>
+#include <nnapi/SharedMemory.h>
 
 namespace aidl::android::hardware::neuralnetworks::utils {
 namespace {
 
+nn::GeneralResult<ndk::ScopedFileDescriptor> clone(const ndk::ScopedFileDescriptor& fd);
+using utils::clone;
+
 template <typename Type>
 nn::GeneralResult<std::vector<Type>> cloneVec(const std::vector<Type>& arguments) {
     std::vector<Type> clonedObjects;
@@ -37,24 +45,52 @@
     return cloneVec(arguments);
 }
 
+nn::GeneralResult<ndk::ScopedFileDescriptor> clone(const ndk::ScopedFileDescriptor& fd) {
+    auto duplicatedFd = NN_TRY(nn::dupFd(fd.get()));
+    return ndk::ScopedFileDescriptor(duplicatedFd.release());
+}
+
+nn::GeneralResult<common::NativeHandle> clone(const common::NativeHandle& handle) {
+    return common::NativeHandle{
+            .fds = NN_TRY(cloneVec(handle.fds)),
+            .ints = handle.ints,
+    };
+}
+
 }  // namespace
 
 nn::GeneralResult<Memory> clone(const Memory& memory) {
-    common::NativeHandle nativeHandle;
-    nativeHandle.ints = memory.handle.ints;
-    nativeHandle.fds.reserve(memory.handle.fds.size());
-    for (const auto& fd : memory.handle.fds) {
-        const int newFd = dup(fd.get());
-        if (newFd < 0) {
-            return NN_ERROR() << "Couldn't dup a file descriptor";
+    switch (memory.getTag()) {
+        case Memory::Tag::ashmem: {
+            const auto& ashmem = memory.get<Memory::Tag::ashmem>();
+            auto handle = common::Ashmem{
+                    .fd = NN_TRY(clone(ashmem.fd)),
+                    .size = ashmem.size,
+            };
+            return Memory::make<Memory::Tag::ashmem>(std::move(handle));
         }
-        nativeHandle.fds.emplace_back(newFd);
+        case Memory::Tag::mappableFile: {
+            const auto& memFd = memory.get<Memory::Tag::mappableFile>();
+            auto handle = common::MappableFile{
+                    .length = memFd.length,
+                    .prot = memFd.prot,
+                    .fd = NN_TRY(clone(memFd.fd)),
+                    .offset = memFd.offset,
+            };
+            return Memory::make<Memory::Tag::mappableFile>(std::move(handle));
+        }
+        case Memory::Tag::hardwareBuffer: {
+            const auto& hardwareBuffer = memory.get<Memory::Tag::hardwareBuffer>();
+            auto handle = graphics::common::HardwareBuffer{
+                    .description = hardwareBuffer.description,
+                    .handle = NN_TRY(clone(hardwareBuffer.handle)),
+            };
+            return Memory::make<Memory::Tag::hardwareBuffer>(std::move(handle));
+        }
     }
-    return Memory{
-            .handle = std::move(nativeHandle),
-            .size = memory.size,
-            .name = memory.name,
-    };
+    return (NN_ERROR() << "Unrecognized Memory::Tag: " << memory.getTag())
+            .
+            operator nn::GeneralResult<Memory>();
 }
 
 nn::GeneralResult<RequestMemoryPool> clone(const RequestMemoryPool& requestPool) {
diff --git a/neuralnetworks/aidl/vts/functional/Android.bp b/neuralnetworks/aidl/vts/functional/Android.bp
index 7804c2a..d5b150a 100644
--- a/neuralnetworks/aidl/vts/functional/Android.bp
+++ b/neuralnetworks/aidl/vts/functional/Android.bp
@@ -50,9 +50,11 @@
     ],
     static_libs: [
         "android.hardware.common-V2-ndk_platform",
+        "android.hardware.graphics.common-V2-ndk_platform",
         "android.hardware.neuralnetworks-V1-ndk_platform",
         "android.hidl.allocator@1.0",
         "android.hidl.memory@1.0",
+        "libaidlcommonsupport",
         "libgmock",
         "libhidlmemory",
         "libneuralnetworks_generated_test_harness",
diff --git a/neuralnetworks/aidl/vts/functional/MemoryDomainTests.cpp b/neuralnetworks/aidl/vts/functional/MemoryDomainTests.cpp
index 596f8ae..e8313f1 100644
--- a/neuralnetworks/aidl/vts/functional/MemoryDomainTests.cpp
+++ b/neuralnetworks/aidl/vts/functional/MemoryDomainTests.cpp
@@ -16,6 +16,7 @@
 
 #define LOG_TAG "neuralnetworks_aidl_hal_test"
 
+#include <aidl/android/hardware/graphics/common/PixelFormat.h>
 #include <android-base/logging.h>
 #include <android/binder_auto_utils.h>
 #include <android/binder_interface_utils.h>
@@ -659,10 +660,26 @@
         return allocateBuffer(preparedModel, inputIndexes, outputIndexes, {});
     }
 
+    size_t getSize(const Memory& memory) {
+        switch (memory.getTag()) {
+            case Memory::Tag::ashmem:
+                return memory.get<Memory::Tag::ashmem>().size;
+            case Memory::Tag::mappableFile:
+                return memory.get<Memory::Tag::mappableFile>().length;
+            case Memory::Tag::hardwareBuffer: {
+                const auto& hardwareBuffer = memory.get<Memory::Tag::hardwareBuffer>();
+                const bool isBlob =
+                        hardwareBuffer.description.format == graphics::common::PixelFormat::BLOB;
+                return isBlob ? hardwareBuffer.description.width : 0;
+            }
+        }
+        return 0;
+    }
+
     Memory allocateSharedMemory(uint32_t size) {
         const auto sharedMemory = nn::createSharedMemory(size).value();
         auto memory = utils::convert(sharedMemory).value();
-        EXPECT_EQ(memory.size, size);
+        EXPECT_EQ(getSize(memory), size);
         return memory;
     }
 
@@ -690,7 +707,7 @@
 
     void initializeDeviceMemory(const std::shared_ptr<IBuffer>& buffer) {
         Memory memory = allocateSharedMemory(kTestOperandDataSize);
-        ASSERT_EQ(memory.size, kTestOperandDataSize);
+        ASSERT_EQ(getSize(memory), kTestOperandDataSize);
         testCopyFrom(buffer, memory, utils::toSigned(kTestOperand.dimensions).value(),
                      ErrorStatus::NONE);
     }
diff --git a/neuralnetworks/aidl/vts/functional/ValidateModel.cpp b/neuralnetworks/aidl/vts/functional/ValidateModel.cpp
index 94d3daf..698c054 100644
--- a/neuralnetworks/aidl/vts/functional/ValidateModel.cpp
+++ b/neuralnetworks/aidl/vts/functional/ValidateModel.cpp
@@ -259,12 +259,16 @@
 size_t sizeForBinder(const Memory& memory) {
     // This is just a guess.
 
-    size_t size = 0;
-    const NativeHandle& handle = memory.handle;
-    size += sizeof(decltype(handle.fds)::value_type) * handle.fds.size();
-    size += sizeof(decltype(handle.ints)::value_type) * handle.ints.size();
-    size += sizeForBinder(memory.name);
-    size += sizeof(memory);
+    size_t size = sizeof(Memory);
+
+    // Only hardwareBuffer type memory has dynamic memory that needs to be accounted for (in the
+    // form of a NativeHandle type). The other other types of memory (MappableFile, Ashmem) use a
+    // single file descriptor (with metadata) instead.
+    if (memory.getTag() == Memory::Tag::hardwareBuffer) {
+        const NativeHandle& handle = memory.get<Memory::Tag::hardwareBuffer>().handle;
+        size += sizeof(decltype(handle.fds)::value_type) * handle.fds.size();
+        size += sizeof(decltype(handle.ints)::value_type) * handle.ints.size();
+    }
 
     return size;
 }
diff --git a/neuralnetworks/utils/common/src/CommonUtils.cpp b/neuralnetworks/utils/common/src/CommonUtils.cpp
index 924ecb2..4d26795 100644
--- a/neuralnetworks/utils/common/src/CommonUtils.cpp
+++ b/neuralnetworks/utils/common/src/CommonUtils.cpp
@@ -89,6 +89,59 @@
                   });
 }
 
+nn::GeneralResult<hidl_handle> createNativeHandleFrom(base::unique_fd fd,
+                                                      const std::vector<int32_t>& ints) {
+    constexpr size_t kIntMax = std::numeric_limits<int>::max();
+    CHECK_LE(ints.size(), kIntMax);
+    native_handle_t* nativeHandle = native_handle_create(1, static_cast<int>(ints.size()));
+    if (nativeHandle == nullptr) {
+        return NN_ERROR() << "Failed to create native_handle";
+    }
+
+    nativeHandle->data[0] = fd.release();
+    std::copy(ints.begin(), ints.end(), nativeHandle->data + 1);
+
+    hidl_handle handle;
+    handle.setTo(nativeHandle, /*shouldOwn=*/true);
+    return handle;
+}
+
+nn::GeneralResult<hidl_memory> createHidlMemoryFrom(const nn::Memory::Ashmem& memory) {
+    auto fd = NN_TRY(nn::dupFd(memory.fd));
+    auto handle = NN_TRY(createNativeHandleFrom(std::move(fd), {}));
+    return hidl_memory("ashmem", std::move(handle), memory.size);
+}
+
+nn::GeneralResult<hidl_memory> createHidlMemoryFrom(const nn::Memory::Fd& memory) {
+    auto fd = NN_TRY(nn::dupFd(memory.fd));
+
+    const auto [lowOffsetBits, highOffsetBits] = nn::getIntsFromOffset(memory.offset);
+    const std::vector<int> ints = {memory.prot, lowOffsetBits, highOffsetBits};
+
+    auto handle = NN_TRY(createNativeHandleFrom(std::move(fd), ints));
+    return hidl_memory("mmap_fd", std::move(handle), memory.size);
+}
+
+nn::GeneralResult<hidl_memory> createHidlMemoryFrom(const nn::Memory::HardwareBuffer& memory) {
+    const auto* ahwb = memory.handle.get();
+    AHardwareBuffer_Desc bufferDesc;
+    AHardwareBuffer_describe(ahwb, &bufferDesc);
+
+    const bool isBlob = bufferDesc.format == AHARDWAREBUFFER_FORMAT_BLOB;
+    const size_t size = isBlob ? bufferDesc.width : 0;
+    const char* const name = isBlob ? "hardware_buffer_blob" : "hardware_buffer";
+
+    const native_handle_t* nativeHandle = AHardwareBuffer_getNativeHandle(ahwb);
+    const hidl_handle hidlHandle(nativeHandle);
+    hidl_handle copiedHandle(hidlHandle);
+
+    return hidl_memory(name, std::move(copiedHandle), size);
+}
+
+nn::GeneralResult<hidl_memory> createHidlMemoryFrom(const nn::Memory::Unknown& memory) {
+    return hidl_memory(memory.name, NN_TRY(hidlHandleFromSharedHandle(memory.handle)), memory.size);
+}
+
 }  // anonymous namespace
 
 nn::Capabilities::OperandPerformanceTable makeQuantized8PerformanceConsistentWithP(
@@ -255,27 +308,7 @@
     if (memory == nullptr) {
         return NN_ERROR() << "Memory must be non-empty";
     }
-    if (const auto* handle = std::get_if<nn::Handle>(&memory->handle)) {
-        return hidl_memory(memory->name, NN_TRY(hidlHandleFromSharedHandle(*handle)), memory->size);
-    }
-
-    const auto* ahwb = std::get<nn::HardwareBufferHandle>(memory->handle).get();
-    AHardwareBuffer_Desc bufferDesc;
-    AHardwareBuffer_describe(ahwb, &bufferDesc);
-
-    if (bufferDesc.format == AHARDWAREBUFFER_FORMAT_BLOB) {
-        CHECK_EQ(memory->size, bufferDesc.width);
-        CHECK_EQ(memory->name, "hardware_buffer_blob");
-    } else {
-        CHECK_EQ(memory->size, 0u);
-        CHECK_EQ(memory->name, "hardware_buffer");
-    }
-
-    const native_handle_t* nativeHandle = AHardwareBuffer_getNativeHandle(ahwb);
-    const hidl_handle hidlHandle(nativeHandle);
-    hidl_handle handle(hidlHandle);
-
-    return hidl_memory(memory->name, std::move(handle), memory->size);
+    return std::visit([](const auto& x) { return createHidlMemoryFrom(x); }, memory->handle);
 }
 
 static uint32_t roundUpToMultiple(uint32_t value, uint32_t multiple) {
@@ -283,14 +316,53 @@
 }
 
 nn::GeneralResult<nn::SharedMemory> createSharedMemoryFromHidlMemory(const hidl_memory& memory) {
-    CHECK_LE(memory.size(), std::numeric_limits<uint32_t>::max());
+    CHECK_LE(memory.size(), std::numeric_limits<size_t>::max());
+    if (!memory.valid()) {
+        return NN_ERROR() << "Unable to convert invalid hidl_memory";
+    }
+
+    if (memory.name() == "ashmem") {
+        if (memory.handle()->numFds != 1) {
+            return NN_ERROR() << "Unable to convert invalid ashmem memory object with "
+                              << memory.handle()->numFds << " numFds, but expected 1";
+        }
+        if (memory.handle()->numInts != 0) {
+            return NN_ERROR() << "Unable to convert invalid ashmem memory object with "
+                              << memory.handle()->numInts << " numInts, but expected 0";
+        }
+        auto handle = nn::Memory::Ashmem{
+                .fd = NN_TRY(nn::dupFd(memory.handle()->data[0])),
+                .size = static_cast<size_t>(memory.size()),
+        };
+        return std::make_shared<const nn::Memory>(nn::Memory{.handle = std::move(handle)});
+    }
+
+    if (memory.name() == "mmap_fd") {
+        if (memory.handle()->numFds != 1) {
+            return NN_ERROR() << "Unable to convert invalid mmap_fd memory object with "
+                              << memory.handle()->numFds << " numFds, but expected 1";
+        }
+        if (memory.handle()->numInts != 3) {
+            return NN_ERROR() << "Unable to convert invalid mmap_fd memory object with "
+                              << memory.handle()->numInts << " numInts, but expected 3";
+        }
+
+        const int fd = memory.handle()->data[0];
+        const int prot = memory.handle()->data[1];
+        const int lower = memory.handle()->data[2];
+        const int higher = memory.handle()->data[3];
+        const size_t offset = nn::getOffsetFromInts(lower, higher);
+
+        return nn::createSharedMemoryFromFd(static_cast<size_t>(memory.size()), prot, fd, offset);
+    }
 
     if (memory.name() != "hardware_buffer_blob") {
-        return std::make_shared<const nn::Memory>(nn::Memory{
+        auto handle = nn::Memory::Unknown{
                 .handle = NN_TRY(sharedHandleFromNativeHandle(memory.handle())),
-                .size = static_cast<uint32_t>(memory.size()),
+                .size = static_cast<size_t>(memory.size()),
                 .name = memory.name(),
-        });
+        };
+        return std::make_shared<const nn::Memory>(nn::Memory{.handle = std::move(handle)});
     }
 
     const auto size = memory.size();
@@ -328,11 +400,7 @@
                << "Can't create AHardwareBuffer from handle. Error: " << status;
     }
 
-    return std::make_shared<const nn::Memory>(nn::Memory{
-            .handle = nn::HardwareBufferHandle(hardwareBuffer, /*takeOwnership=*/true),
-            .size = static_cast<uint32_t>(memory.size()),
-            .name = memory.name(),
-    });
+    return nn::createSharedMemoryFromAHWB(hardwareBuffer, /*takeOwnership=*/true);
 }
 
 nn::GeneralResult<hidl_handle> hidlHandleFromSharedHandle(const nn::Handle& handle) {
diff --git a/soundtrigger/2.4/Android.bp b/soundtrigger/2.4/Android.bp
new file mode 100644
index 0000000..44befc3
--- /dev/null
+++ b/soundtrigger/2.4/Android.bp
@@ -0,0 +1,30 @@
+// This file is autogenerated by hidl-gen -Landroidbp.
+
+package {
+    // See: http://go/android-license-faq
+    // A large-scale-change added 'default_applicable_licenses' to import
+    // all of the 'license_kinds' from "hardware_interfaces_license"
+    // to get the below license kinds:
+    //   SPDX-license-identifier-Apache-2.0
+    default_applicable_licenses: ["hardware_interfaces_license"],
+}
+
+hidl_interface {
+    name: "android.hardware.soundtrigger@2.4",
+    root: "android.hardware",
+    srcs: [
+        "ISoundTriggerHw.hal",
+        "ISoundTriggerHwCallback.hal",
+        "ISoundTriggerHwGlobalCallback.hal",
+    ],
+    interfaces: [
+        "android.hardware.audio.common@2.0",
+        "android.hardware.soundtrigger@2.0",
+        "android.hardware.soundtrigger@2.1",
+        "android.hardware.soundtrigger@2.2",
+        "android.hardware.soundtrigger@2.3",
+        "android.hidl.base@1.0",
+        "android.hidl.safe_union@1.0",
+    ],
+    gen_java: true,
+}
diff --git a/soundtrigger/2.4/ISoundTriggerHw.hal b/soundtrigger/2.4/ISoundTriggerHw.hal
new file mode 100644
index 0000000..fd39303
--- /dev/null
+++ b/soundtrigger/2.4/ISoundTriggerHw.hal
@@ -0,0 +1,190 @@
+/*
+ * 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.soundtrigger@2.4;
+
+import @2.0::SoundModelHandle;
+import @2.1::ISoundTriggerHw.SoundModel;
+import @2.1::ISoundTriggerHw.PhraseSoundModel;
+import @2.3::ISoundTriggerHw;
+import @2.3::RecognitionConfig;
+import ISoundTriggerHwCallback;
+import ISoundTriggerHwGlobalCallback;
+
+/**
+ * SoundTrigger HAL interface. Used for hardware recognition of hotwords
+ * and other sounds.
+ *
+ * Important notes about the threading model:
+ * ==========================================
+ * Both this interface and the corresponding callback interface use a synchronized 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.
+ *
+ * Similarly, it is expected that a single call to startRecognition() generates at most one event
+ * (the model automatically becomes stopped when the event occurs, until explicitly started again)
+ * and that after a modelUnloaded() event no more events would be sent regarding the model.
+ * Note that a getModelState() call may generate a recognition event, but this event DOES NOT modify
+ * the model state - the model remains started.
+ *
+ * The HAL is expected to correctly handle a stopRecognition() call even after it sent an event
+ * indicating that recognition is stopped and an unloadModel() call even after it sent an event
+ * indicating that it has been unloaded. This is required in order to prevent race conditions
+ * between these calls. 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 will
+ * call unloadModel() on models that have been preemptively unloaded by the HAL.
+ *
+ * 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 a successful return code in this case.
+ * - startRecognition() may be called on a model that has been preemptively unloaded. In this case,
+ *   the HAL must return -EBUSY 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.
+ *
+ * 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.
+ * - 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 framework will no longer enforce constraints on concurrent loading of models, as expressed
+ *   in the Properties (these properties are merely hints at this point and may be deprecated in the
+ *   future.
+ * - The HAL implementation is free to reject starting of any model at any time by having the
+ *   respective start*() method return -EBUSY.
+ * - The HAL implementation is free to reject loading of any model at any time by having the
+ *   respective load*() method return -EBUSY.
+ * - 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 `ABORT` 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 newly added 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 tryAgain() 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 arrives, the framework 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).
+ */
+interface ISoundTriggerHw extends @2.3::ISoundTriggerHw {
+    /**
+     * 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.
+     */
+    registerGlobalCallback(ISoundTriggerHwGlobalCallback callback);
+
+    /**
+     * Load a sound model. Once loaded, recognition of this model can be
+     * started and stopped.
+     * The implementation returns a unique handle used by other functions
+     * (unloadSoundModel(), startRecognition*(), etc...
+     *
+     * Must have the exact same semantics as loadSoundModel from ISoundTriggerHw@2.3 except that the
+     * return values have changed and that there is no cookie provided (the implementation may pass
+     * any value to the callback, as it is ignored).
+     *
+     * @param soundModel A SoundModel structure describing the sound model
+     *     to load.
+     * @param callback The callback interface on which the soundModelCallback*()
+     *     method must be called upon completion and modelUnloaded() upon preempted unload.
+     * @return retval Operation completion status: 0 in case of success,
+     *     -EBUSY in case the operation is temporarily unavailable (but possible in general).
+     * @return modelHandle A unique handle assigned by the HAL for use by the
+     *     framework when controlling activity for this sound model.
+     */
+    loadSoundModel_2_4(SoundModel soundModel, ISoundTriggerHwCallback callback)
+            generates (int32_t retval, SoundModelHandle modelHandle);
+
+    /**
+     * Load a key phrase sound model. Once loaded, recognition of this model can
+     * be started and stopped. Only one active recognition per model at a time.
+     * The SoundTrigger service must handle concurrent recognition requests by
+     * different users/applications on the same model.
+     * The implementation returns a unique handle used by other functions
+     * (unloadSoundModel(), startRecognition*(), etc...
+     *
+     * Must have the exact same semantics as loadPhraseSoundModel from ISoundTriggerHw@2.3 except
+     * that the return values have changed and that there is no cookie provided (the implementation
+     * may pass any value to the callback, as it is ignored).
+     *
+     * @param soundModel A PhraseSoundModel structure describing the sound model
+     *     to load.
+     * @param callback The callback interface on which the soundModelCallback*()
+     *     method must be called upon completion and modelUnloaded() upon preempted unload.
+     * @return retval Operation completion status: 0 in case of success,
+     *     -EBUSY in case the operation is temporarily unavailable (but possible in general).
+     * @return modelHandle A unique handle assigned by the HAL for use by the
+     *     framework when controlling activity for this sound model.
+     */
+    loadPhraseSoundModel_2_4(PhraseSoundModel soundModel, ISoundTriggerHwCallback callback)
+            generates (int32_t retval, SoundModelHandle modelHandle);
+
+    /**
+     * Start recognition on a given model. Only one recognition active
+     * at a time per model. Once recognition succeeds or fails, the callback
+     * associated with the model handle is called.
+     *
+     * Must have the exact same semantics as startRecognition from ISoundTriggerHw@2.3 except that
+     * there are different expectations of the return value and that there is no cookie provided
+     * (the implementation may pass any value to the callback, as it is ignored).
+     *
+     * @param modelHandle the handle of the sound model to use for recognition
+     * @param config A RecognitionConfig structure containing attributes of the
+     *     recognition to perform
+     * @param callback The callback interface on which the recognitionCallback()
+     *     method must be called upon recognition.
+     * @return retval Operation completion status: 0 in case of success,
+     *     -EBUSY in case the operation is temporarily unavailable (but possible in general), or in
+     *            case model has been preemtively unloaded.
+     */
+    startRecognition_2_4(SoundModelHandle modelHandle, RecognitionConfig config)
+            generates (int32_t retval);
+};
diff --git a/soundtrigger/2.4/ISoundTriggerHwCallback.hal b/soundtrigger/2.4/ISoundTriggerHwCallback.hal
new file mode 100644
index 0000000..594deb0
--- /dev/null
+++ b/soundtrigger/2.4/ISoundTriggerHwCallback.hal
@@ -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.soundtrigger@2.4;
+
+import @2.0::SoundModelHandle;
+import @2.1::ISoundTriggerHwCallback;
+
+/**
+ * SoundTrigger HAL per-model Callback interface.
+ */
+interface ISoundTriggerHwCallback extends @2.1::ISoundTriggerHwCallback {
+    /**
+     * Callback method called by the HAL when a model has been unloaded at the HAL implementation's
+     * discretion. Only a stopped model may be unloaded.
+     * This event is NOT sent as part of an unload sequence initiated by the client.
+     *
+     * @param model The model handle.
+     */
+    modelUnloaded(SoundModelHandle model);
+};
diff --git a/soundtrigger/2.4/ISoundTriggerHwGlobalCallback.hal b/soundtrigger/2.4/ISoundTriggerHwGlobalCallback.hal
new file mode 100644
index 0000000..2f1a977
--- /dev/null
+++ b/soundtrigger/2.4/ISoundTriggerHwGlobalCallback.hal
@@ -0,0 +1,32 @@
+/*
+ * 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.soundtrigger@2.4;
+
+/**
+ * SoundTrigger HAL callback interface for events not associated with a particular model.
+ */
+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 -EBUSY is guaranteed to fail again if
+     * retried, until this callback is delivered.
+     */
+    onResourcesAvailable();
+};
diff --git a/soundtrigger/2.4/cli/Android.bp b/soundtrigger/2.4/cli/Android.bp
new file mode 100644
index 0000000..8d0979b
--- /dev/null
+++ b/soundtrigger/2.4/cli/Android.bp
@@ -0,0 +1,17 @@
+package {
+    // See: http://go/android-license-faq
+    // A large-scale-change added 'default_applicable_licenses' to import
+    // all of the 'license_kinds' from "hardware_interfaces_license"
+    // to get the below license kinds:
+    //   SPDX-license-identifier-Apache-2.0
+    default_applicable_licenses: ["hardware_interfaces_license"],
+}
+
+java_binary {
+    name: "sthal_cli_2.4",
+    wrapper: "sthal_cli_2.4",
+    srcs: ["java/**/*.java"],
+    static_libs: [
+        "android.hardware.soundtrigger-V2.4-java",
+    ],
+}
diff --git a/soundtrigger/2.4/cli/OWNERS b/soundtrigger/2.4/cli/OWNERS
new file mode 100644
index 0000000..e21b66e
--- /dev/null
+++ b/soundtrigger/2.4/cli/OWNERS
@@ -0,0 +1 @@
+include /media/java/android/media/soundtrigger_middleware/OWNERS
diff --git a/soundtrigger/2.4/cli/java/android/hardware/soundtrigger/V2_4/cli/SthalCli.java b/soundtrigger/2.4/cli/java/android/hardware/soundtrigger/V2_4/cli/SthalCli.java
new file mode 100644
index 0000000..4931105
--- /dev/null
+++ b/soundtrigger/2.4/cli/java/android/hardware/soundtrigger/V2_4/cli/SthalCli.java
@@ -0,0 +1,401 @@
+/*
+ * 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.soundtrigger.V2_4.cli;
+
+import android.hardware.soundtrigger.V2_0.PhraseRecognitionExtra;
+import android.hardware.soundtrigger.V2_0.RecognitionMode;
+import android.hardware.soundtrigger.V2_0.SoundModelType;
+import android.hardware.soundtrigger.V2_3.OptionalModelParameterRange;
+import android.hardware.soundtrigger.V2_4.ISoundTriggerHw;
+import android.hardware.soundtrigger.V2_4.ISoundTriggerHwCallback;
+import android.hardware.soundtrigger.V2_4.ISoundTriggerHwGlobalCallback;
+import android.os.HidlMemoryUtil;
+import android.os.HwBinder;
+import android.os.RemoteException;
+import android.os.SystemProperties;
+
+import java.util.Scanner;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ConcurrentMap;
+
+/**
+ * This is a quick-and-dirty sound trigger HAL console mock.
+ *
+ * It would only work on userdebug builds.
+ *
+ * When this app is started, it will initially:
+ * - Register a ISoundTriggerHw HAL with an instance name "mock".
+ * - Set a sysprop that tells SoundTriggerMiddlewareService to try to connect to the mock instance
+ * rather than the default one.
+ * - Reboot the real (default) HAL.
+ *
+ * In response to that, SoundTriggerMiddlewareService is going to connect to the mock HAL and resume
+ * normal operation.
+ *
+ * Our mock HAL will print to stdout every call it receives as well as expose a basic set of
+ * operations for sending event callbacks to the client. This allows us to simulate the frameworks
+ * behavior in response to different HAL behaviors.
+ */
+public class SthalCli {
+    private static SoundTriggerImpl mService;
+    private static final Scanner scanner = new Scanner(System.in);
+
+    public static void main(String[] args) {
+        try {
+            System.out.println("Registering mock STHAL");
+            HwBinder.setTrebleTestingOverride(true);
+            mService = new SoundTriggerImpl();
+            mService.registerAsService("mock");
+
+            System.out.println("Rebooting STHAL");
+            SystemProperties.set("debug.soundtrigger_middleware.use_mock_hal", "2");
+            SystemProperties.set("sys.audio.restart.hal", "1");
+
+            while (processCommand()) ;
+        } catch (Exception e) {
+            e.printStackTrace();
+        } finally {
+            cleanup();
+        }
+    }
+
+    private static void cleanup() {
+        System.out.println("Cleaning up.");
+        SystemProperties.set("debug.soundtrigger_middleware.use_mock_hal", null);
+        HwBinder.setTrebleTestingOverride(false);
+    }
+
+    private static boolean processCommand() {
+        String line = scanner.nextLine();
+        String[] tokens = line.split("\\s+");
+        if (tokens.length < 1) {
+            return false;
+        }
+        switch (tokens[0]) {
+            case "q":
+                return false;
+
+            case "a":
+                mService.sendOnResourcesAvailable();
+                return true;
+
+            case "u":
+                mService.sendModelUnloaded(Integer.parseInt(tokens[1]));
+                return true;
+
+            case "r":
+                mService.sendRecognitionEvent(Integer.parseInt(tokens[1]),
+                        Integer.parseInt(tokens[2]));
+                return true;
+
+            case "p":
+                mService.sendPhraseRecognitionEvent(Integer.parseInt(tokens[1]),
+                        Integer.parseInt(tokens[2]));
+                return true;
+
+            case "d":
+                mService.dumpModels();
+                return true;
+
+            case "h":
+                System.out.print("Available commands:\n" + "h - help\n" + "q - quit\n"
+                        + "a - send onResourcesAvailable event\n"
+                        + "u <model> - send modelUnloaded event\n"
+                        + "r <model> <status> - send recognitionEvent\n"
+                        + "p <model> <status> - send phraseRecognitionEvent\n"
+                        + "d - dump models\n");
+
+            default:
+                return true;
+        }
+    }
+
+    private static class SoundTriggerImpl extends ISoundTriggerHw.Stub {
+        static class Model {
+            final ISoundTriggerHwCallback callback;
+            final SoundModel model;
+            final PhraseSoundModel phraseModel;
+            public android.hardware.soundtrigger.V2_3.RecognitionConfig config = null;
+
+            Model(ISoundTriggerHwCallback callback, SoundModel model) {
+                this.callback = callback;
+                this.model = model;
+                this.phraseModel = null;
+            }
+
+            Model(ISoundTriggerHwCallback callback, PhraseSoundModel model) {
+                this.callback = callback;
+                this.model = null;
+                this.phraseModel = model;
+            }
+        }
+
+        private ISoundTriggerHwGlobalCallback mGlobalCallback;
+        private final ConcurrentMap<Integer, Model> mLoadedModels = new ConcurrentHashMap<>();
+        private int mHandleCounter = 1;
+
+        public void dumpModels() {
+            mLoadedModels.forEach((handle, model) -> {
+                System.out.println("+++ Model " + handle);
+                System.out.println("    config = " + model.config);
+                android.hardware.soundtrigger.V2_3.RecognitionConfig recognitionConfig =
+                        model.config;
+                if (recognitionConfig != null) {
+                    System.out.println("    ACTIVE recognitionConfig = " + recognitionConfig);
+                } else {
+                    System.out.println("    INACTIVE");
+                }
+            });
+        }
+
+        public void sendOnResourcesAvailable() {
+            if (mGlobalCallback != null) {
+                try {
+                    mGlobalCallback.onResourcesAvailable();
+                } catch (RemoteException e) {
+                    e.printStackTrace();
+                }
+            }
+        }
+
+        public void sendRecognitionEvent(int modelHandle, int status) {
+            Model model = mLoadedModels.get(modelHandle);
+            if (model != null && model.config != null) {
+                android.hardware.soundtrigger.V2_1.ISoundTriggerHwCallback.RecognitionEvent event =
+                        new android.hardware.soundtrigger.V2_1.ISoundTriggerHwCallback.RecognitionEvent();
+                event.header.model = modelHandle;
+                event.header.type = SoundModelType.GENERIC;
+                event.header.status = status;
+                event.header.captureSession = model.config.base.header.captureHandle;
+                event.header.captureAvailable = true;
+                event.header.audioConfig.channelMask = 16;
+                event.header.audioConfig.format = 1;
+                event.header.audioConfig.sampleRateHz = 16000;
+                event.data = HidlMemoryUtil.byteArrayToHidlMemory(new byte[0]);
+                try {
+                    model.callback.recognitionCallback_2_1(event, 0);
+                } catch (RemoteException e) {
+                    e.printStackTrace();
+                }
+                model.config = null;
+            }
+        }
+
+        public void sendPhraseRecognitionEvent(int modelHandle, int status) {
+            Model model = mLoadedModels.get(modelHandle);
+            if (model != null && model.config != null) {
+                android.hardware.soundtrigger.V2_1.ISoundTriggerHwCallback.PhraseRecognitionEvent
+                        event =
+                        new android.hardware.soundtrigger.V2_1.ISoundTriggerHwCallback.PhraseRecognitionEvent();
+                event.common.header.model = modelHandle;
+                event.common.header.type = SoundModelType.KEYPHRASE;
+                event.common.header.status = status;
+                event.common.header.captureSession = model.config.base.header.captureHandle;
+                event.common.header.captureAvailable = true;
+                event.common.header.audioConfig.channelMask = 16;
+                event.common.header.audioConfig.format = 1;
+                event.common.header.audioConfig.sampleRateHz = 16000;
+                event.common.data = HidlMemoryUtil.byteArrayToHidlMemory(new byte[0]);
+                if (!model.phraseModel.phrases.isEmpty()) {
+                    PhraseRecognitionExtra extra = new PhraseRecognitionExtra();
+                    extra.id = model.phraseModel.phrases.get(0).id;
+                    extra.confidenceLevel = 100;
+                    extra.recognitionModes = model.phraseModel.phrases.get(0).recognitionModes;
+                    event.phraseExtras.add(extra);
+                }
+                try {
+                    model.callback.phraseRecognitionCallback_2_1(event, 0);
+                } catch (RemoteException e) {
+                    e.printStackTrace();
+                }
+                model.config = null;
+            }
+        }
+
+        public void sendModelUnloaded(int modelHandle) {
+            Model model = mLoadedModels.remove(modelHandle);
+            if (model != null) {
+                try {
+                    model.callback.modelUnloaded(modelHandle);
+                } catch (RemoteException e) {
+                    e.printStackTrace();
+                }
+            }
+        }
+
+        @Override
+        public void registerGlobalCallback(ISoundTriggerHwGlobalCallback callback) {
+            System.out.println("registerGlobalCallback()");
+            mGlobalCallback = callback;
+        }
+
+        @Override
+        public void loadSoundModel_2_4(SoundModel soundModel, ISoundTriggerHwCallback callback,
+                loadSoundModel_2_4Callback _hidl_cb) {
+            int handle = mHandleCounter++;
+            System.out.printf("loadSoundModel_2_4(soundModel=%s) -> %d%n", soundModel, handle);
+            mLoadedModels.put(handle, new Model(callback, soundModel));
+            _hidl_cb.onValues(0, handle);
+        }
+
+        @Override
+        public void loadPhraseSoundModel_2_4(PhraseSoundModel soundModel,
+                ISoundTriggerHwCallback callback, loadPhraseSoundModel_2_4Callback _hidl_cb) {
+            int handle = mHandleCounter++;
+            System.out.printf("loadPhraseSoundModel_2_4(soundModel=%s) -> %d%n", soundModel,
+                    handle);
+            mLoadedModels.put(handle, new Model(callback, soundModel));
+            _hidl_cb.onValues(0, handle);
+        }
+
+        @Override
+        public int startRecognition_2_4(int modelHandle,
+                android.hardware.soundtrigger.V2_3.RecognitionConfig config) {
+            System.out.printf("startRecognition_2_4(modelHandle=%d)%n", modelHandle);
+            Model model = mLoadedModels.get(modelHandle);
+            if (model != null) {
+                model.config = config;
+            }
+            return 0;
+        }
+
+        @Override
+        public void getProperties_2_3(getProperties_2_3Callback _hidl_cb) {
+            System.out.println("getProperties_2_3()");
+            android.hardware.soundtrigger.V2_3.Properties properties =
+                    new android.hardware.soundtrigger.V2_3.Properties();
+            properties.base.implementor = "Android";
+            properties.base.description = "Mock STHAL";
+            properties.base.maxSoundModels = 2;
+            properties.base.maxKeyPhrases = 1;
+            properties.base.recognitionModes =
+                    RecognitionMode.VOICE_TRIGGER | RecognitionMode.GENERIC_TRIGGER;
+            _hidl_cb.onValues(0, properties);
+        }
+
+        @Override
+        public void queryParameter(int modelHandle, int modelParam,
+                queryParameterCallback _hidl_cb) {
+            _hidl_cb.onValues(0, new OptionalModelParameterRange());
+        }
+
+        @Override
+        public int getModelState(int modelHandle) {
+            System.out.printf("getModelState(modelHandle=%d)%n", modelHandle);
+            return 0;
+        }
+
+        @Override
+        public int unloadSoundModel(int modelHandle) {
+            System.out.printf("unloadSoundModel(modelHandle=%d)%n", modelHandle);
+            return 0;
+        }
+
+        @Override
+        public int stopRecognition(int modelHandle) {
+            System.out.printf("stopRecognition(modelHandle=%d)%n", modelHandle);
+            Model model = mLoadedModels.get(modelHandle);
+            if (model != null) {
+                model.config = null;
+            }
+            return 0;
+        }
+
+        @Override
+        public void debug(android.os.NativeHandle fd, java.util.ArrayList<String> options) {
+            if (!options.isEmpty()) {
+                switch (options.get(0)) {
+                    case "reboot":
+                        System.out.println("Received a reboot request. Exiting.");
+                        cleanup();
+                        System.exit(1);
+                }
+            }
+        }
+
+        ////////////////////////////////////////////////////////////////////////////////////////////
+        // Everything below is not implemented and not expected to be called.
+
+        @Override
+        public int startRecognition_2_3(int modelHandle,
+                android.hardware.soundtrigger.V2_3.RecognitionConfig config) {
+            throw new UnsupportedOperationException();
+        }
+
+        @Override
+        public int setParameter(int modelHandle, int modelParam, int value) {
+            throw new UnsupportedOperationException();
+        }
+
+        @Override
+        public void getParameter(int modelHandle, int modelParam, getParameterCallback _hidl_cb) {
+            throw new UnsupportedOperationException();
+        }
+
+        @Override
+        public void loadSoundModel_2_1(SoundModel soundModel,
+                android.hardware.soundtrigger.V2_1.ISoundTriggerHwCallback callback, int cookie,
+                loadSoundModel_2_1Callback _hidl_cb) {
+            throw new UnsupportedOperationException();
+        }
+
+        @Override
+        public void loadPhraseSoundModel_2_1(PhraseSoundModel soundModel,
+                android.hardware.soundtrigger.V2_1.ISoundTriggerHwCallback callback, int cookie,
+                loadPhraseSoundModel_2_1Callback _hidl_cb) {
+            throw new UnsupportedOperationException();
+        }
+
+        @Override
+        public int startRecognition_2_1(int modelHandle, RecognitionConfig config,
+                android.hardware.soundtrigger.V2_1.ISoundTriggerHwCallback callback, int cookie) {
+            throw new UnsupportedOperationException();
+        }
+
+        @Override
+        public void getProperties(getPropertiesCallback _hidl_cb) {
+            throw new UnsupportedOperationException();
+        }
+
+        @Override
+        public void loadSoundModel(
+                android.hardware.soundtrigger.V2_0.ISoundTriggerHw.SoundModel soundModel,
+                android.hardware.soundtrigger.V2_0.ISoundTriggerHwCallback callback, int cookie,
+                loadSoundModelCallback _hidl_cb) {
+            throw new UnsupportedOperationException();
+        }
+
+        @Override
+        public void loadPhraseSoundModel(
+                android.hardware.soundtrigger.V2_0.ISoundTriggerHw.PhraseSoundModel soundModel,
+                android.hardware.soundtrigger.V2_0.ISoundTriggerHwCallback callback, int cookie,
+                loadPhraseSoundModelCallback _hidl_cb) {
+            throw new UnsupportedOperationException();
+        }
+
+        @Override
+        public int startRecognition(int modelHandle,
+                android.hardware.soundtrigger.V2_0.ISoundTriggerHw.RecognitionConfig config,
+                android.hardware.soundtrigger.V2_0.ISoundTriggerHwCallback callback, int cookie) {
+            throw new UnsupportedOperationException();
+        }
+
+        @Override
+        public int stopAllRecognitions() {
+            throw new UnsupportedOperationException();
+        }
+    }
+}
diff --git a/soundtrigger/2.4/cli/sthal_cli_2.4 b/soundtrigger/2.4/cli/sthal_cli_2.4
new file mode 100644
index 0000000..0801464
--- /dev/null
+++ b/soundtrigger/2.4/cli/sthal_cli_2.4
@@ -0,0 +1,7 @@
+#!/system/bin/sh
+# Script to start "sthal_cli_2.4" on the device
+#
+base=/system
+export CLASSPATH=$base/framework/sthal_cli_2.4.jar
+exec app_process $base/bin android.hardware.soundtrigger.V2_4.cli.SthalCli "$@"
+
diff --git a/soundtrigger/2.4/vts/functional/Android.bp b/soundtrigger/2.4/vts/functional/Android.bp
new file mode 100644
index 0000000..4b7ae91
--- /dev/null
+++ b/soundtrigger/2.4/vts/functional/Android.bp
@@ -0,0 +1,41 @@
+//
+// Copyright (C) 2021 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+package {
+    // See: http://go/android-license-faq
+    // A large-scale-change added 'default_applicable_licenses' to import
+    // all of the 'license_kinds' from "hardware_interfaces_license"
+    // to get the below license kinds:
+    //   SPDX-license-identifier-Apache-2.0
+    default_applicable_licenses: ["hardware_interfaces_license"],
+}
+
+cc_test {
+    name: "VtsHalSoundtriggerV2_4TargetTest",
+    defaults: ["VtsHalTargetTestDefaults"],
+    srcs: ["VtsHalSoundtriggerV2_4TargetTest.cpp"],
+    static_libs: [
+        "android.hardware.soundtrigger@2.0",
+        "android.hardware.soundtrigger@2.1",
+        "android.hardware.soundtrigger@2.2",
+        "android.hardware.soundtrigger@2.3",
+        "android.hardware.soundtrigger@2.4",
+    ],
+    test_suites: [
+        "general-tests",
+        "vts",
+    ],
+}
diff --git a/soundtrigger/2.4/vts/functional/VtsHalSoundtriggerV2_4TargetTest.cpp b/soundtrigger/2.4/vts/functional/VtsHalSoundtriggerV2_4TargetTest.cpp
new file mode 100644
index 0000000..13d7005
--- /dev/null
+++ b/soundtrigger/2.4/vts/functional/VtsHalSoundtriggerV2_4TargetTest.cpp
@@ -0,0 +1,84 @@
+/*
+ * Copyright (C) 2021 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define LOG_TAG "SoundTriggerHidlHalTest"
+
+#include <android-base/logging.h>
+#include <android/hardware/audio/common/2.0/types.h>
+#include <android/hardware/soundtrigger/2.4/ISoundTriggerHwGlobalCallback.h>
+#include <android/hardware/soundtrigger/2.4/ISoundTriggerHw.h>
+#include <gtest/gtest.h>
+#include <hidl/GtestPrinter.h>
+#include <hidl/ServiceManagement.h>
+
+using ::android::sp;
+using ::android::hardware::Return;
+using ::android::hardware::Status;
+using ::android::hardware::soundtrigger::V2_4::ISoundTriggerHw;
+using ::android::hardware::soundtrigger::V2_4::ISoundTriggerHwGlobalCallback;
+
+/**
+ * Test class holding the instance of the SoundTriggerHW service to test.
+ * The passed parameter is the registered name of the implementing service
+ * supplied by INSTANTIATE_TEST_SUITE_P() call.
+ */
+class SoundTriggerHidlTest : public testing::TestWithParam<std::string> {
+public:
+    void SetUp() override {
+        mSoundtrigger = ISoundTriggerHw::getService(GetParam());
+
+        ASSERT_NE(mSoundtrigger, nullptr);
+        LOG(INFO) << "Test is remote " << mSoundtrigger->isRemote();
+    }
+
+protected:
+    sp<ISoundTriggerHw> mSoundtrigger;
+};
+
+/**
+ * Empty test is in place to ensure service is initialized.
+ * Due to the nature of SoundTrigger HAL providing an interface for
+ * proprietary or vendor specific implementations, limited testing on
+ * individual APIs is possible.
+ */
+TEST_P(SoundTriggerHidlTest, ServiceIsInstantiated) {}
+
+class GlobalCallback : public ISoundTriggerHwGlobalCallback {
+    Return<void> onResourcesAvailable() override {
+        return Status::ok();
+    }
+};
+
+/**
+ * Test ISoundTriggerHw::registerGlobalCallback method
+ *
+ * Verifies that:
+ * - the implementation implements the method
+ * - the method returns no error
+ */
+TEST_P(SoundTriggerHidlTest, RegisterGlobalCallback) {
+    Return<void> hidlReturn;
+    sp<ISoundTriggerHwGlobalCallback> callback = new GlobalCallback();
+    hidlReturn = mSoundtrigger->registerGlobalCallback(callback);
+    EXPECT_TRUE(hidlReturn.isOk());
+}
+
+GTEST_ALLOW_UNINSTANTIATED_PARAMETERIZED_TEST(SoundTriggerHidlTest);
+
+INSTANTIATE_TEST_SUITE_P(
+        PerInstance, SoundTriggerHidlTest,
+        testing::ValuesIn(android::hardware::getAllHalInstanceNames(ISoundTriggerHw::descriptor)),
+        android::hardware::PrintInstanceNameToString);
diff --git a/soundtrigger/aidl/Android.bp b/soundtrigger/aidl/Android.bp
new file mode 100644
index 0000000..6c084da
--- /dev/null
+++ b/soundtrigger/aidl/Android.bp
@@ -0,0 +1,28 @@
+aidl_interface {
+    name: "android.hardware.soundtrigger3",
+    vendor_available: true,
+    flags: ["-Werror", "-Weverything", ],
+    srcs: [
+        "android/hardware/soundtrigger3/ISoundTriggerHw.aidl",
+        "android/hardware/soundtrigger3/ISoundTriggerHwCallback.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/aidl/aidl_api/android.hardware.soundtrigger3/current/android/hardware/soundtrigger3/ISoundTriggerHw.aidl b/soundtrigger/aidl/aidl_api/android.hardware.soundtrigger3/current/android/hardware/soundtrigger3/ISoundTriggerHw.aidl
new file mode 100644
index 0000000..bbfe7d9
--- /dev/null
+++ b/soundtrigger/aidl/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/aidl/aidl_api/android.hardware.soundtrigger3/current/android/hardware/soundtrigger3/ISoundTriggerHwCallback.aidl b/soundtrigger/aidl/aidl_api/android.hardware.soundtrigger3/current/android/hardware/soundtrigger3/ISoundTriggerHwCallback.aidl
new file mode 100644
index 0000000..152dfed
--- /dev/null
+++ b/soundtrigger/aidl/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/aidl/aidl_api/android.hardware.soundtrigger3/current/android/hardware/soundtrigger3/ISoundTriggerHwGlobalCallback.aidl b/soundtrigger/aidl/aidl_api/android.hardware.soundtrigger3/current/android/hardware/soundtrigger3/ISoundTriggerHwGlobalCallback.aidl
new file mode 100644
index 0000000..6dfee9f
--- /dev/null
+++ b/soundtrigger/aidl/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();
+}
diff --git a/soundtrigger/aidl/android/hardware/soundtrigger3/ISoundTriggerHw.aidl b/soundtrigger/aidl/android/hardware/soundtrigger3/ISoundTriggerHw.aidl
new file mode 100644
index 0000000..2a3fc64
--- /dev/null
+++ b/soundtrigger/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/aidl/android/hardware/soundtrigger3/ISoundTriggerHwCallback.aidl b/soundtrigger/aidl/android/hardware/soundtrigger3/ISoundTriggerHwCallback.aidl
new file mode 100644
index 0000000..049ca65
--- /dev/null
+++ b/soundtrigger/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/aidl/android/hardware/soundtrigger3/ISoundTriggerHwGlobalCallback.aidl b/soundtrigger/aidl/android/hardware/soundtrigger3/ISoundTriggerHwGlobalCallback.aidl
new file mode 100644
index 0000000..d6d8630
--- /dev/null
+++ b/soundtrigger/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/aidl/cli/Android.bp b/soundtrigger/aidl/cli/Android.bp
new file mode 100644
index 0000000..880903a
--- /dev/null
+++ b/soundtrigger/aidl/cli/Android.bp
@@ -0,0 +1,8 @@
+java_binary {
+    name: "sthal_cli_3",
+    wrapper: "sthal_cli_3",
+    srcs: ["java/**/*.java"],
+    static_libs: [
+        "android.hardware.soundtrigger3-V1-java",
+    ],
+}
diff --git a/soundtrigger/aidl/cli/OWNERS b/soundtrigger/aidl/cli/OWNERS
new file mode 100644
index 0000000..e21b66e
--- /dev/null
+++ b/soundtrigger/aidl/cli/OWNERS
@@ -0,0 +1 @@
+include /media/java/android/media/soundtrigger_middleware/OWNERS
diff --git a/soundtrigger/aidl/cli/java/android/hardware/soundtrigger3/cli/SthalCli.java b/soundtrigger/aidl/cli/java/android/hardware/soundtrigger3/cli/SthalCli.java
new file mode 100644
index 0000000..d3e1aa7
--- /dev/null
+++ b/soundtrigger/aidl/cli/java/android/hardware/soundtrigger3/cli/SthalCli.java
@@ -0,0 +1,351 @@
+/*
+ * 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.cli;
+
+import android.annotation.NonNull;
+import android.hardware.soundtrigger3.ISoundTriggerHw;
+import android.hardware.soundtrigger3.ISoundTriggerHwCallback;
+import android.hardware.soundtrigger3.ISoundTriggerHwGlobalCallback;
+import android.media.audio.common.AudioConfig;
+import android.media.soundtrigger.ConfidenceLevel;
+import android.media.soundtrigger.ModelParameterRange;
+import android.media.soundtrigger.PhraseRecognitionEvent;
+import android.media.soundtrigger.PhraseRecognitionExtra;
+import android.media.soundtrigger.PhraseSoundModel;
+import android.media.soundtrigger.Properties;
+import android.media.soundtrigger.RecognitionConfig;
+import android.media.soundtrigger.RecognitionEvent;
+import android.media.soundtrigger.RecognitionMode;
+import android.media.soundtrigger.SoundModel;
+import android.media.soundtrigger.SoundModelType;
+import android.os.HwBinder;
+import android.os.ParcelFileDescriptor;
+import android.os.RemoteException;
+import android.os.ServiceManager;
+import android.os.SystemProperties;
+
+import java.util.Scanner;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ConcurrentMap;
+
+/**
+ * This is a quick-and-dirty sound trigger HAL console mock.
+ *
+ * It would only work on userdebug builds.
+ *
+ * When this app is started, it will initially:
+ * - Register a ISoundTriggerHw HAL with an instance name "mock".
+ * - Set a sysprop that tells SoundTriggerMiddlewareService to try to connect to the mock instance
+ * rather than the default one.
+ * - Reboot the real (default) HAL.
+ *
+ * In response to that, SoundTriggerMiddlewareService is going to connect to the mock HAL and resume
+ * normal operation.
+ *
+ * Our mock HAL will print to stdout every call it receives as well as expose a basic set of
+ * operations for sending event callbacks to the client. This allows us to simulate the frameworks
+ * behavior in response to different HAL behaviors.
+ */
+public class SthalCli {
+    private static SoundTriggerImpl mService;
+    private static final Scanner scanner = new Scanner(System.in);
+
+    public static void main(String[] args) {
+        try {
+            printUsage();
+
+            System.out.println("Registering mock STHAL");
+            mService = new SoundTriggerImpl();
+            // This allows us to register the service, even if it is not declared in the manifest.
+            mService.forceDowngradeToSystemStability();
+            ServiceManager.addService(ISoundTriggerHw.class.getCanonicalName() + "/mock", mService);
+
+            System.out.println("Rebooting STHAL");
+            SystemProperties.set("debug.soundtrigger_middleware.use_mock_hal", "3");
+            SystemProperties.set("sys.audio.restart.hal", "1");
+
+            while (processCommand()) ;
+        } catch (Exception e) {
+            e.printStackTrace();
+        } finally {
+            cleanup();
+        }
+    }
+
+    private static void cleanup() {
+        System.out.println("Cleaning up.");
+        SystemProperties.set("debug.soundtrigger_middleware.use_mock_hal", null);
+        HwBinder.setTrebleTestingOverride(false);
+    }
+
+    private static boolean processCommand() {
+        String line = scanner.nextLine();
+        String[] tokens = line.split("\\s+");
+        if (tokens.length < 1) {
+            return false;
+        }
+        switch (tokens[0]) {
+            case "q":
+                return false;
+
+            case "a":
+                mService.sendOnResourcesAvailable();
+                return true;
+
+            case "u":
+                mService.sendModelUnloaded(Integer.parseInt(tokens[1]));
+                return true;
+
+            case "r":
+                mService.sendRecognitionEvent(Integer.parseInt(tokens[1]),
+                        Integer.parseInt(tokens[2]));
+                return true;
+
+            case "p":
+                mService.sendPhraseRecognitionEvent(Integer.parseInt(tokens[1]),
+                        Integer.parseInt(tokens[2]));
+                return true;
+
+            case "d":
+                mService.dumpModels();
+                return true;
+
+            default:
+                printUsage();
+                return true;
+        }
+    }
+
+    private static void printUsage() {
+        System.out.print(
+                "Sound Trigger HAL v3 mock\n"
+                + "Available commands:\n"
+                + "h - help\n"
+                + "q - quit\n"
+                + "a - send onResourcesAvailable event\n"
+                + "u <model> - send modelUnloaded event\n"
+                + "r <model> <status> - send recognitionEvent\n"
+                + "p <model> <status> - send phraseRecognitionEvent\n"
+                + "d - dump models\n");
+    }
+
+    private static class SoundTriggerImpl extends ISoundTriggerHw.Stub {
+        static class Model {
+            final ISoundTriggerHwCallback callback;
+            final SoundModel model;
+            final PhraseSoundModel phraseModel;
+            public RecognitionConfig config = null;
+
+            Model(ISoundTriggerHwCallback callback, SoundModel model) {
+                this.callback = callback;
+                this.model = model;
+                this.phraseModel = null;
+            }
+
+            Model(ISoundTriggerHwCallback callback, PhraseSoundModel model) {
+                this.callback = callback;
+                this.model = null;
+                this.phraseModel = model;
+            }
+        }
+
+        private ISoundTriggerHwGlobalCallback mGlobalCallback;
+        private final ConcurrentMap<Integer, Model> mLoadedModels = new ConcurrentHashMap<>();
+        private int mHandleCounter = 1;
+
+        public void dumpModels() {
+            mLoadedModels.forEach((handle, model) -> {
+                System.out.println("+++ Model " + handle);
+                System.out.println("    config = " + model.config);
+                RecognitionConfig recognitionConfig = model.config;
+                if (recognitionConfig != null) {
+                    System.out.println("    ACTIVE recognitionConfig = " + recognitionConfig);
+                } else {
+                    System.out.println("    INACTIVE");
+                }
+            });
+        }
+
+        public void sendOnResourcesAvailable() {
+            if (mGlobalCallback != null) {
+                try {
+                    mGlobalCallback.onResourcesAvailable();
+                } catch (RemoteException e) {
+                    e.printStackTrace();
+                }
+            }
+        }
+
+        public void sendRecognitionEvent(int modelHandle, int status) {
+            Model model = mLoadedModels.get(modelHandle);
+            if (model != null && model.config != null) {
+                RecognitionEvent event = new RecognitionEvent();
+                event.type = SoundModelType.GENERIC;
+                event.status = status;
+                event.captureAvailable = true;
+                event.audioConfig.channelMask = 16;
+                event.audioConfig.format = 1;
+                event.audioConfig.sampleRateHz = 16000;
+                try {
+                    model.callback.recognitionCallback(modelHandle, event);
+                } catch (RemoteException e) {
+                    e.printStackTrace();
+                }
+                model.config = null;
+            }
+        }
+
+        public void sendPhraseRecognitionEvent(int modelHandle, int status) {
+            Model model = mLoadedModels.get(modelHandle);
+            if (model != null && model.config != null) {
+                PhraseRecognitionEvent event = new PhraseRecognitionEvent();
+                event.common = new RecognitionEvent();
+                event.common.type = SoundModelType.KEYPHRASE;
+                event.common.status = status;
+                event.common.captureAvailable = true;
+                event.common.audioConfig = new AudioConfig();
+                event.common.audioConfig.channelMask = 16;
+                event.common.audioConfig.format = 1;
+                event.common.audioConfig.sampleRateHz = 16000;
+                if (model.phraseModel.phrases.length > 0) {
+                    PhraseRecognitionExtra extra = new PhraseRecognitionExtra();
+                    extra.id = model.phraseModel.phrases[0].id;
+                    extra.confidenceLevel = 100;
+                    extra.recognitionModes = model.phraseModel.phrases[0].recognitionModes;
+                    extra.levels = new ConfidenceLevel[0];
+                    event.phraseExtras = new PhraseRecognitionExtra[]{extra};
+                } else {
+                    event.phraseExtras = new PhraseRecognitionExtra[0];
+                }
+                try {
+                    model.callback.phraseRecognitionCallback(modelHandle, event);
+                } catch (RemoteException e) {
+                    e.printStackTrace();
+                }
+                model.config = null;
+            }
+        }
+
+        public void sendModelUnloaded(int modelHandle) {
+            Model model = mLoadedModels.remove(modelHandle);
+            if (model != null) {
+                try {
+                    model.callback.modelUnloaded(modelHandle);
+                } catch (RemoteException e) {
+                    e.printStackTrace();
+                }
+            }
+        }
+
+        @Override
+        public void registerGlobalCallback(ISoundTriggerHwGlobalCallback callback) {
+            System.out.println("registerGlobalCallback()");
+            mGlobalCallback = callback;
+        }
+
+        @Override
+        public int loadSoundModel(SoundModel soundModel, ISoundTriggerHwCallback callback) {
+            int handle = mHandleCounter++;
+            System.out.printf("loadSoundModel(soundModel=%s) -> %d%n", soundModel, handle);
+            mLoadedModels.put(handle, new Model(callback, soundModel));
+            return handle;
+        }
+
+        @Override
+        public int loadPhraseSoundModel(PhraseSoundModel soundModel,
+                ISoundTriggerHwCallback callback) {
+            int handle = mHandleCounter++;
+            System.out.printf("loadPhraseSoundModel(soundModel=%s) -> %d%n", soundModel, handle);
+            mLoadedModels.put(handle, new Model(callback, soundModel));
+            return handle;
+        }
+
+        @Override
+        public void startRecognition(int modelHandle, int deviceHandle, int ioHandle,
+                RecognitionConfig config) {
+            System.out.printf("startRecognition(modelHandle=%d, deviceHandle=%d, ioHandle=%d)%n",
+                    modelHandle, deviceHandle, ioHandle);
+            Model model = mLoadedModels.get(modelHandle);
+            if (model != null) {
+                model.config = config;
+            }
+        }
+
+        @Override
+        public Properties getProperties() {
+            System.out.println("getProperties()");
+            Properties properties = new Properties();
+            properties.implementor = "Android";
+            properties.description = "Mock STHAL";
+            properties.maxSoundModels = 2;
+            properties.maxKeyPhrases = 1;
+            properties.recognitionModes =
+                    RecognitionMode.VOICE_TRIGGER | RecognitionMode.GENERIC_TRIGGER;
+            return properties;
+        }
+
+        @Override
+        public ModelParameterRange queryParameter(int modelHandle, int modelParam) {
+            System.out.printf("queryParameter(modelHandle=%d, modelParam=%d)%n", modelHandle,
+                    modelParam);
+            return null;
+        }
+
+        @Override
+        public void forceRecognitionEvent(int modelHandle) {
+            System.out.printf("getModelState(modelHandle=%d)%n", modelHandle);
+        }
+
+        @Override
+        public void unloadSoundModel(int modelHandle) {
+            System.out.printf("unloadSoundModel(modelHandle=%d)%n", modelHandle);
+        }
+
+        @Override
+        public void stopRecognition(int modelHandle) {
+            System.out.printf("stopRecognition(modelHandle=%d)%n", modelHandle);
+            Model model = mLoadedModels.get(modelHandle);
+            if (model != null) {
+                model.config = null;
+            }
+        }
+
+        @Override
+        public int handleShellCommand(@NonNull ParcelFileDescriptor in,
+                @NonNull ParcelFileDescriptor out, @NonNull ParcelFileDescriptor err,
+                @NonNull String[] args) {
+            if (args.length > 0) {
+                switch (args[0]) {
+                    case "reboot":
+                        System.out.println("Received a reboot request. Exiting.");
+                        cleanup();
+                        System.exit(1);
+                }
+            }
+            return 0;
+        }
+
+        @Override
+        public void setParameter(int modelHandle, int modelParam, int value) {
+            throw new IllegalArgumentException();
+        }
+
+        @Override
+        public int getParameter(int modelHandle, int modelParam) {
+            throw new IllegalArgumentException();
+        }
+    }
+}
diff --git a/soundtrigger/aidl/cli/sthal_cli_3 b/soundtrigger/aidl/cli/sthal_cli_3
new file mode 100644
index 0000000..f157c50
--- /dev/null
+++ b/soundtrigger/aidl/cli/sthal_cli_3
@@ -0,0 +1,6 @@
+#!/system/bin/sh
+# Script to start "sthal_cli_3" on the device
+#
+base=/system
+export CLASSPATH=$base/framework/sthal_cli_3.jar
+exec app_process $base/bin android.hardware.soundtrigger3.cli.SthalCli "$@"