diff --git a/core/java/android/view/inputmethod/InputMethodSubtype.java b/core/java/android/view/inputmethod/InputMethodSubtype.java
index 96b6b437a64b9..bdfcb03286327 100644
--- a/core/java/android/view/inputmethod/InputMethodSubtype.java
+++ b/core/java/android/view/inputmethod/InputMethodSubtype.java
@@ -76,6 +76,10 @@ public final class InputMethodSubtype implements Parcelable {
     /** {@hide} */
     public static final int SUBTYPE_ID_NONE = 0;
 
+    private static final String SUBTYPE_MODE_KEYBOARD = "keyboard";
+
+    private static final String UNDEFINED_LANGUAGE_TAG = "und";
+
     private final boolean mIsAuxiliary;
     private final boolean mOverridesImplicitlyEnabledSubtype;
     private final boolean mIsAsciiCapable;
@@ -432,6 +436,34 @@ public final class InputMethodSubtype implements Parcelable {
         return result;
     }
 
+    /**
+     * Determines whether this {@link InputMethodSubtype} can be used as the key of mapping rules
+     * between {@link InputMethodSubtype} and hardware keyboard layout.
+     *
+     * <p>Note that in a future build may require different rules.  Design the system so that the
+     * system can automatically take care of any rule changes upon OTAs.</p>
+     *
+     * @return {@code true} if this {@link InputMethodSubtype} can be used as the key of mapping
+     *         rules between {@link InputMethodSubtype} and hardware keyboard layout.
+     * @hide
+     */
+    public boolean isSuitableForPhysicalKeyboardLayoutMapping() {
+        if (hashCode() == SUBTYPE_ID_NONE) {
+            return false;
+        }
+        if (!TextUtils.equals(getMode(), SUBTYPE_MODE_KEYBOARD)) {
+            return false;
+        }
+        if (isAuxiliary()) {
+            return false;
+        }
+        final String langTag = getCanonicalizedLanguageTag();
+        if (langTag.isEmpty() || TextUtils.equals(langTag, UNDEFINED_LANGUAGE_TAG)) {
+            return false;
+        }
+        return true;
+    }
+
     /**
      * @return The mode of the subtype.
      */
diff --git a/core/tests/coretests/src/android/view/inputmethod/InputMethodSubtypeTest.java b/core/tests/coretests/src/android/view/inputmethod/InputMethodSubtypeTest.java
index bd292f04ba96e..297b07fac3404 100644
--- a/core/tests/coretests/src/android/view/inputmethod/InputMethodSubtypeTest.java
+++ b/core/tests/coretests/src/android/view/inputmethod/InputMethodSubtypeTest.java
@@ -35,6 +35,7 @@ import org.junit.runner.RunWith;
 
 import java.util.Locale;
 import java.util.Objects;
+import java.util.function.Supplier;
 
 @SmallTest
 @RunWith(AndroidJUnit4.class)
@@ -157,6 +158,34 @@ public class InputMethodSubtypeTest {
         assertEquals(subtype.getCanonicalizedLanguageTag(), expectedLanguageTag);
     }
 
+    @Test
+    public void testIsSuitableForPhysicalKeyboardLayoutMapping() {
+        final Supplier<InputMethodSubtypeBuilder> getValidBuilder = () ->
+                new InputMethodSubtypeBuilder()
+                        .setLanguageTag("en-US")
+                        .setIsAuxiliary(false)
+                        .setSubtypeMode("keyboard")
+                        .setSubtypeId(1);
+
+        assertTrue(getValidBuilder.get().build().isSuitableForPhysicalKeyboardLayoutMapping());
+
+        // mode == "voice" is not suitable.
+        assertFalse(getValidBuilder.get().setSubtypeMode("voice").build()
+                .isSuitableForPhysicalKeyboardLayoutMapping());
+
+        // Auxiliary subtype not suitable.
+        assertFalse(getValidBuilder.get().setIsAuxiliary(true).build()
+                .isSuitableForPhysicalKeyboardLayoutMapping());
+
+        // languageTag == null is not suitable.
+        assertFalse(getValidBuilder.get().setLanguageTag(null).build()
+                .isSuitableForPhysicalKeyboardLayoutMapping());
+
+        // languageTag == "und" is not suitable.
+        assertFalse(getValidBuilder.get().setLanguageTag("und").build()
+                .isSuitableForPhysicalKeyboardLayoutMapping());
+    }
+
     private static InputMethodSubtype cloneViaParcel(final InputMethodSubtype original) {
         Parcel parcel = null;
         try {