diff --git a/services/inputflinger/tests/InputMapperTest.h b/services/inputflinger/tests/InputMapperTest.h
index 870e11b..4271a70 100644
--- a/services/inputflinger/tests/InputMapperTest.h
+++ b/services/inputflinger/tests/InputMapperTest.h
@@ -114,11 +114,12 @@
     T& constructAndAddMapper(Args... args) {
         // ensure a device entry exists for this eventHubId
         mDevice->addEmptyEventHubDevice(EVENTHUB_ID);
-        // configure the empty device
-        configureDevice(/*changes=*/{});
 
-        return mDevice->constructAndAddMapper<T>(EVENTHUB_ID, mFakePolicy->getReaderConfiguration(),
-                                                 args...);
+        auto& mapper =
+                mDevice->constructAndAddMapper<T>(EVENTHUB_ID,
+                                                  mFakePolicy->getReaderConfiguration(), args...);
+        configureDevice(/*changes=*/{});
+        return mapper;
     }
 
     void setDisplayInfoAndReconfigure(ui::LogicalDisplayId displayId, int32_t width, int32_t height,
diff --git a/services/inputflinger/tests/InputReader_test.cpp b/services/inputflinger/tests/InputReader_test.cpp
index fe238f3..e6367b7 100644
--- a/services/inputflinger/tests/InputReader_test.cpp
+++ b/services/inputflinger/tests/InputReader_test.cpp
@@ -4179,6 +4179,51 @@
     ASSERT_EQ(AKEY_EVENT_FLAG_FROM_SYSTEM | AKEY_EVENT_FLAG_KEEP_TOUCH_MODE, args.flags);
 }
 
+/**
+ * When there is more than one KeyboardInputMapper for an InputDevice, each mapper should produce
+ * events that use the shared keyboard source across all mappers. This is to ensure that each
+ * input device generates key events in a consistent manner, regardless of which mapper produces
+ * the event.
+ */
+TEST_F(KeyboardInputMapperTest, UsesSharedKeyboardSource) {
+    mFakeEventHub->addKey(EVENTHUB_ID, KEY_HOME, 0, AKEYCODE_HOME, POLICY_FLAG_WAKE);
+
+    // Add a mapper with SOURCE_KEYBOARD
+    KeyboardInputMapper& keyboardMapper =
+            constructAndAddMapper<KeyboardInputMapper>(AINPUT_SOURCE_KEYBOARD);
+
+    process(keyboardMapper, ARBITRARY_TIME, 0, EV_KEY, KEY_HOME, 1);
+    ASSERT_NO_FATAL_FAILURE(
+            mFakeListener->assertNotifyKeyWasCalled(WithSource(AINPUT_SOURCE_KEYBOARD)));
+    process(keyboardMapper, ARBITRARY_TIME, 0, EV_KEY, KEY_HOME, 0);
+    ASSERT_NO_FATAL_FAILURE(
+            mFakeListener->assertNotifyKeyWasCalled(WithSource(AINPUT_SOURCE_KEYBOARD)));
+
+    // Add a mapper with SOURCE_DPAD
+    KeyboardInputMapper& dpadMapper =
+            constructAndAddMapper<KeyboardInputMapper>(AINPUT_SOURCE_DPAD);
+    for (auto* mapper : {&keyboardMapper, &dpadMapper}) {
+        process(*mapper, ARBITRARY_TIME, 0, EV_KEY, KEY_HOME, 1);
+        ASSERT_NO_FATAL_FAILURE(mFakeListener->assertNotifyKeyWasCalled(
+                WithSource(AINPUT_SOURCE_KEYBOARD | AINPUT_SOURCE_DPAD)));
+        process(*mapper, ARBITRARY_TIME, 0, EV_KEY, KEY_HOME, 0);
+        ASSERT_NO_FATAL_FAILURE(mFakeListener->assertNotifyKeyWasCalled(
+                WithSource(AINPUT_SOURCE_KEYBOARD | AINPUT_SOURCE_DPAD)));
+    }
+
+    // Add a mapper with SOURCE_GAMEPAD
+    KeyboardInputMapper& gamepadMapper =
+            constructAndAddMapper<KeyboardInputMapper>(AINPUT_SOURCE_GAMEPAD);
+    for (auto* mapper : {&keyboardMapper, &dpadMapper, &gamepadMapper}) {
+        process(*mapper, ARBITRARY_TIME, 0, EV_KEY, KEY_HOME, 1);
+        ASSERT_NO_FATAL_FAILURE(mFakeListener->assertNotifyKeyWasCalled(
+                WithSource(AINPUT_SOURCE_KEYBOARD | AINPUT_SOURCE_DPAD | AINPUT_SOURCE_GAMEPAD)));
+        process(*mapper, ARBITRARY_TIME, 0, EV_KEY, KEY_HOME, 0);
+        ASSERT_NO_FATAL_FAILURE(mFakeListener->assertNotifyKeyWasCalled(
+                WithSource(AINPUT_SOURCE_KEYBOARD | AINPUT_SOURCE_DPAD | AINPUT_SOURCE_GAMEPAD)));
+    }
+}
+
 // --- KeyboardInputMapperTest_ExternalAlphabeticDevice ---
 
 class KeyboardInputMapperTest_ExternalAlphabeticDevice : public InputMapperTest {
diff --git a/services/inputflinger/tests/KeyboardInputMapper_test.cpp b/services/inputflinger/tests/KeyboardInputMapper_test.cpp
index e9ab13a..4d322e9 100644
--- a/services/inputflinger/tests/KeyboardInputMapper_test.cpp
+++ b/services/inputflinger/tests/KeyboardInputMapper_test.cpp
@@ -65,6 +65,8 @@
         mFakePolicy = sp<FakeInputReaderPolicy>::make();
         EXPECT_CALL(mMockInputReaderContext, getPolicy).WillRepeatedly(Return(mFakePolicy.get()));
 
+        ON_CALL((*mDevice), getSources).WillByDefault(Return(AINPUT_SOURCE_KEYBOARD));
+
         mMapper = createInputMapper<KeyboardInputMapper>(*mDeviceContext, mReaderConfiguration,
                                                          AINPUT_SOURCE_KEYBOARD);
     }