diff --git a/core/java/android/hardware/radio/ITuner.aidl b/core/java/android/hardware/radio/ITuner.aidl
index 429f1f351a937..7bf234b9d5a4b 100644
--- a/core/java/android/hardware/radio/ITuner.aidl
+++ b/core/java/android/hardware/radio/ITuner.aidl
@@ -80,14 +80,14 @@ interface ITuner {
     void setConfigFlag(int flag, boolean value);
 
     /**
-     * @param parameters Vendor-specific key-value pairs, must be Map<String, String>
-     * @return Vendor-specific key-value pairs, must be Map<String, String>
+     * @param parameters Vendor-specific key-value pairs
+     * @return Vendor-specific key-value pairs
      */
-    Map setParameters(in Map parameters);
+    Map<String, String> setParameters(in Map<String, String> parameters);
 
     /**
      * @param keys Parameter keys to fetch
-     * @return Vendor-specific key-value pairs, must be Map<String, String>
+     * @return Vendor-specific key-value pairs
      */
-    Map getParameters(in List<String> keys);
+    Map<String, String> getParameters(in List<String> keys);
 }
diff --git a/core/java/android/hardware/radio/ITunerCallback.aidl b/core/java/android/hardware/radio/ITunerCallback.aidl
index b32daa5a76097..f98947b50e345 100644
--- a/core/java/android/hardware/radio/ITunerCallback.aidl
+++ b/core/java/android/hardware/radio/ITunerCallback.aidl
@@ -36,7 +36,7 @@ oneway interface ITunerCallback {
     void onProgramListUpdated(in ProgramList.Chunk chunk);
 
     /**
-     * @param parameters Vendor-specific key-value pairs, must be Map<String, String>
+     * @param parameters Vendor-specific key-value pairs
      */
-    void onParametersUpdated(in Map parameters);
+    void onParametersUpdated(in Map<String, String> parameters);
 }
diff --git a/core/java/android/hardware/radio/TunerCallbackAdapter.java b/core/java/android/hardware/radio/TunerCallbackAdapter.java
index beff0f7607f81..e3f7001d87402 100644
--- a/core/java/android/hardware/radio/TunerCallbackAdapter.java
+++ b/core/java/android/hardware/radio/TunerCallbackAdapter.java
@@ -220,7 +220,7 @@ class TunerCallbackAdapter extends ITunerCallback.Stub {
     }
 
     @Override
-    public void onParametersUpdated(Map parameters) {
+    public void onParametersUpdated(Map<String, String> parameters) {
         mHandler.post(() -> mCallback.onParametersUpdated(parameters));
     }
 }
diff --git a/services/core/java/com/android/server/broadcastradio/hal1/Tuner.java b/services/core/java/com/android/server/broadcastradio/hal1/Tuner.java
index f2e44ee132ed8..e7118ad72bf42 100644
--- a/services/core/java/com/android/server/broadcastradio/hal1/Tuner.java
+++ b/services/core/java/com/android/server/broadcastradio/hal1/Tuner.java
@@ -28,10 +28,8 @@ import android.os.IBinder;
 import android.os.RemoteException;
 import android.util.Slog;
 
-import java.util.Collections;
 import java.util.List;
 import java.util.Map;
-import java.util.Objects;
 
 class Tuner extends ITuner.Stub {
     private static final String TAG = "BroadcastRadioService.Tuner";
@@ -292,12 +290,12 @@ class Tuner extends ITuner.Stub {
     }
 
     @Override
-    public Map setParameters(Map parameters) {
+    public Map<String, String> setParameters(Map<String, String> parameters) {
         throw new UnsupportedOperationException("Not supported by HAL 1.x");
     }
 
     @Override
-    public Map getParameters(List<String> keys) {
+    public Map<String, String> getParameters(List<String> keys) {
         throw new UnsupportedOperationException("Not supported by HAL 1.x");
     }
 }
diff --git a/services/core/java/com/android/server/broadcastradio/hal1/TunerCallback.java b/services/core/java/com/android/server/broadcastradio/hal1/TunerCallback.java
index 7a6d9647bf433..867d5b4b6f49b 100644
--- a/services/core/java/com/android/server/broadcastradio/hal1/TunerCallback.java
+++ b/services/core/java/com/android/server/broadcastradio/hal1/TunerCallback.java
@@ -18,12 +18,10 @@ package com.android.server.broadcastradio.hal1;
 
 import android.annotation.NonNull;
 import android.annotation.Nullable;
-import android.hardware.radio.ITuner;
 import android.hardware.radio.ITunerCallback;
 import android.hardware.radio.ProgramList;
 import android.hardware.radio.ProgramSelector;
 import android.hardware.radio.RadioManager;
-import android.hardware.radio.RadioMetadata;
 import android.hardware.radio.RadioTuner;
 import android.os.IBinder;
 import android.os.RemoteException;
@@ -31,7 +29,6 @@ import android.util.Slog;
 
 import java.util.List;
 import java.util.Map;
-import java.util.Objects;
 import java.util.Set;
 import java.util.concurrent.atomic.AtomicReference;
 import java.util.stream.Collectors;
@@ -176,7 +173,7 @@ class TunerCallback implements ITunerCallback {
     }
 
     @Override
-    public void onParametersUpdated(Map parameters) {
+    public void onParametersUpdated(Map<String, String> parameters) {
         Slog.e(TAG, "Not applicable for HAL 1.x");
     }
 
diff --git a/services/core/java/com/android/server/broadcastradio/hal2/TunerSession.java b/services/core/java/com/android/server/broadcastradio/hal2/TunerSession.java
index 7ab3bdd859e46..7d8c6a427d8a6 100644
--- a/services/core/java/com/android/server/broadcastradio/hal2/TunerSession.java
+++ b/services/core/java/com/android/server/broadcastradio/hal2/TunerSession.java
@@ -299,7 +299,7 @@ class TunerSession extends ITuner.Stub {
     }
 
     @Override
-    public Map setParameters(Map parameters) {
+    public Map<String, String> setParameters(Map<String, String> parameters) {
         synchronized (mLock) {
             checkNotClosedLocked();
             return Convert.vendorInfoFromHal(Utils.maybeRethrow(
@@ -308,7 +308,7 @@ class TunerSession extends ITuner.Stub {
     }
 
     @Override
-    public Map getParameters(List<String> keys) {
+    public Map<String, String> getParameters(List<String> keys) {
         synchronized (mLock) {
             checkNotClosedLocked();
             return Convert.vendorInfoFromHal(Utils.maybeRethrow(