diff --git a/wifi/1.5/Android.bp b/wifi/1.5/Android.bp
index 7c04c69..0887c6b 100644
--- a/wifi/1.5/Android.bp
+++ b/wifi/1.5/Android.bp
@@ -20,6 +20,7 @@
         "IWifiNanIface.hal",
         "IWifiNanIfaceEventCallback.hal",
         "IWifiStaIface.hal",
+        "IWifiEventCallback.hal",
     ],
     interfaces: [
         "android.hardware.wifi@1.0",
diff --git a/wifi/1.5/IWifi.hal b/wifi/1.5/IWifi.hal
index 66d0a9c..28b808e 100644
--- a/wifi/1.5/IWifi.hal
+++ b/wifi/1.5/IWifi.hal
@@ -17,6 +17,8 @@
 package android.hardware.wifi@1.5;
 
 import @1.4::IWifi;
+import IWifiEventCallback;
+import @1.0::WifiStatus;
 
 /**
  * This is the root of the HAL module and is the interface returned when
@@ -24,4 +26,21 @@
  * module loaded in the system.
  * IWifi.getChip() must return @1.5::IWifiChip
  */
-interface IWifi extends @1.4::IWifi {};
+interface IWifi extends @1.4::IWifi {
+  /**
+   * Requests notifications of significant events for the HAL. Multiple calls to
+   * this must register multiple callbacks each of which must receive all
+   * events. |IWifiEventCallback| object registration must be independent of the
+   * state of the rest of the HAL and must persist though stops/starts. These
+   * objects must be deleted when the corresponding client process is dead.
+   *
+   * @param callback An instance of the |IWifiEventCallback| HIDL interface
+   *        object.
+   * @return status WifiStatus of the operation.
+   *         Possible status codes:
+   *         |WifiStatusCode.SUCCESS|,
+   *         |WifiStatusCode.UNKNOWN|
+   */
+  registerEventCallback_1_5(IWifiEventCallback callback)
+      generates (WifiStatus status);
+};
diff --git a/wifi/1.5/IWifiEventCallback.hal b/wifi/1.5/IWifiEventCallback.hal
new file mode 100644
index 0000000..17dce39
--- /dev/null
+++ b/wifi/1.5/IWifiEventCallback.hal
@@ -0,0 +1,21 @@
+/*
+ * 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.wifi@1.5;
+
+import @1.0::IWifiEventCallback;
+
+interface IWifiEventCallback extends @1.0::IWifiEventCallback {};
diff --git a/wifi/1.5/default/wifi.cpp b/wifi/1.5/default/wifi.cpp
index da98db8..b4037e9 100644
--- a/wifi/1.5/default/wifi.cpp
+++ b/wifi/1.5/default/wifi.cpp
@@ -50,13 +50,21 @@
 }
 
 Return<void> Wifi::registerEventCallback(
-    const sp<IWifiEventCallback>& event_callback,
+    const sp<V1_0::IWifiEventCallback>& event_callback,
     registerEventCallback_cb hidl_status_cb) {
     return validateAndCall(this, WifiStatusCode::ERROR_UNKNOWN,
                            &Wifi::registerEventCallbackInternal, hidl_status_cb,
                            event_callback);
 }
 
+Return<void> Wifi::registerEventCallback_1_5(
+    const sp<V1_5::IWifiEventCallback>& event_callback,
+    registerEventCallback_1_5_cb hidl_status_cb) {
+    return validateAndCall(this, WifiStatusCode::ERROR_UNKNOWN,
+                           &Wifi::registerEventCallbackInternal_1_5,
+                           hidl_status_cb, event_callback);
+}
+
 Return<bool> Wifi::isStarted() { return run_state_ != RunState::STOPPED; }
 
 Return<void> Wifi::start(start_cb hidl_status_cb) {
@@ -95,7 +103,13 @@
 }
 
 WifiStatus Wifi::registerEventCallbackInternal(
-    const sp<IWifiEventCallback>& event_callback) {
+    const sp<V1_0::IWifiEventCallback>& event_callback __unused) {
+    // Deprecated support for this callback.
+    return createWifiStatus(WifiStatusCode::ERROR_NOT_SUPPORTED);
+}
+
+WifiStatus Wifi::registerEventCallbackInternal_1_5(
+    const sp<V1_5::IWifiEventCallback>& event_callback) {
     if (!event_cb_handler_.addCallback(event_callback)) {
         return createWifiStatus(WifiStatusCode::ERROR_UNKNOWN);
     }
diff --git a/wifi/1.5/default/wifi.h b/wifi/1.5/default/wifi.h
index 825c0bc..840bdfd 100644
--- a/wifi/1.5/default/wifi.h
+++ b/wifi/1.5/default/wifi.h
@@ -52,8 +52,11 @@
 
     // HIDL methods exposed.
     Return<void> registerEventCallback(
-        const sp<IWifiEventCallback>& event_callback,
+        const sp<V1_0::IWifiEventCallback>& event_callback,
         registerEventCallback_cb hidl_status_cb) override;
+    Return<void> registerEventCallback_1_5(
+        const sp<V1_5::IWifiEventCallback>& event_callback,
+        registerEventCallback_1_5_cb hidl_status_cb) override;
     Return<bool> isStarted() override;
     Return<void> start(start_cb hidl_status_cb) override;
     Return<void> stop(stop_cb hidl_status_cb) override;
@@ -67,7 +70,9 @@
 
     // Corresponding worker functions for the HIDL methods.
     WifiStatus registerEventCallbackInternal(
-        const sp<IWifiEventCallback>& event_callback);
+        const sp<V1_0::IWifiEventCallback>& event_callback __unused);
+    WifiStatus registerEventCallbackInternal_1_5(
+        const sp<V1_5::IWifiEventCallback>& event_callback);
     WifiStatus startInternal();
     WifiStatus stopInternal(std::unique_lock<std::recursive_mutex>* lock);
     std::pair<WifiStatus, std::vector<ChipId>> getChipIdsInternal();
@@ -87,7 +92,7 @@
     std::shared_ptr<feature_flags::WifiFeatureFlags> feature_flags_;
     RunState run_state_;
     std::vector<sp<WifiChip>> chips_;
-    hidl_callback_util::HidlCallbackHandler<IWifiEventCallback>
+    hidl_callback_util::HidlCallbackHandler<V1_5::IWifiEventCallback>
         event_cb_handler_;
 
     DISALLOW_COPY_AND_ASSIGN(Wifi);