diff --git a/services/inputflinger/InputReaderBase.cpp b/services/inputflinger/InputReaderBase.cpp
new file mode 100644
index 0000000..17a116e
--- /dev/null
+++ b/services/inputflinger/InputReaderBase.cpp
@@ -0,0 +1,91 @@
+/*
+ * Copyright (C) 2018 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 "InputReaderBase"
+
+//#define LOG_NDEBUG 0
+
+#include "InputReaderBase.h"
+
+#include <android/log.h>
+#include <android-base/stringprintf.h>
+
+#define INDENT "  "
+#define INDENT2 "    "
+#define INDENT3 "      "
+#define INDENT4 "        "
+#define INDENT5 "          "
+
+using android::base::StringPrintf;
+
+namespace android {
+
+// --- InputReaderThread ---
+
+InputReaderThread::InputReaderThread(const sp<InputReaderInterface>& reader) :
+        Thread(/*canCallJava*/ true), mReader(reader) {
+}
+
+InputReaderThread::~InputReaderThread() {
+}
+
+bool InputReaderThread::threadLoop() {
+    mReader->loopOnce();
+    return true;
+}
+
+// --- InputReaderConfiguration ---
+
+std::optional<DisplayViewport> InputReaderConfiguration::getDisplayViewport(
+        ViewportType viewportType, const std::string& uniqueDisplayId) const {
+    for (const DisplayViewport& currentViewport : mDisplays) {
+        if (currentViewport.type == viewportType) {
+            if (uniqueDisplayId.empty() ||
+                    (!uniqueDisplayId.empty() && uniqueDisplayId == currentViewport.uniqueId)) {
+                return std::make_optional(currentViewport);
+            }
+        }
+    }
+    return std::nullopt;
+}
+
+void InputReaderConfiguration::setDisplayViewports(const std::vector<DisplayViewport>& viewports) {
+    mDisplays = viewports;
+}
+
+void InputReaderConfiguration::dump(std::string& dump) const {
+    for (const DisplayViewport& viewport : mDisplays) {
+        dumpViewport(dump, viewport);
+    }
+}
+
+void InputReaderConfiguration::dumpViewport(std::string& dump, const DisplayViewport& viewport)
+        const {
+    dump += StringPrintf(INDENT4 "%s\n", viewport.toString().c_str());
+}
+
+
+// -- TouchAffineTransformation --
+void TouchAffineTransformation::applyTo(float& x, float& y) const {
+    float newX, newY;
+    newX = x * x_scale + y * x_ymix + x_offset;
+    newY = x * y_xmix + y * y_scale + y_offset;
+
+    x = newX;
+    y = newY;
+}
+
+} // namespace android
\ No newline at end of file