diff --git a/tests/Android.mk b/tests/Android.mk
new file mode 100644
index 0000000..5bbda93
--- /dev/null
+++ b/tests/Android.mk
@@ -0,0 +1,12 @@
+LOCAL_PATH := $(call my-dir)
+
+include $(CLEAR_VARS)
+
+LOCAL_SRC_FILES := \
+	worker_test.cpp
+
+LOCAL_MODULE := hwc-drm-tests
+LOCAL_STATIC_LIBRARIES := libdrmhwc_utils
+LOCAL_C_INCLUDES := external/drm_hwcomposer
+
+include $(BUILD_NATIVE_TEST)
diff --git a/tests/worker_test.cpp b/tests/worker_test.cpp
new file mode 100644
index 0000000..38f91db
--- /dev/null
+++ b/tests/worker_test.cpp
@@ -0,0 +1,110 @@
+#include <gtest/gtest.h>
+#include <hardware/hardware.h>
+
+#include <chrono>
+
+#include "worker.h"
+
+using android::Worker;
+
+struct TestWorker : public Worker {
+  TestWorker()
+      : Worker("test-worker", HAL_PRIORITY_URGENT_DISPLAY),
+        value(0),
+        enabled_(false) {
+  }
+
+  int Init() {
+    return InitWorker();
+  }
+
+  void Routine() {
+    Lock();
+    if (!enabled_) {
+      int ret = WaitForSignalOrExitLocked();
+      if (ret == -EINTR) {
+        Unlock();
+        return;
+      }
+      // should only reached here if it was enabled
+      if (!enabled_)
+        printf("Shouldn't reach here while disabled %d %d\n", value, ret);
+    }
+    value++;
+    Unlock();
+  }
+
+  void Control(bool enable) {
+    bool changed = false;
+    Lock();
+    if (enabled_ != enable) {
+      enabled_ = enable;
+      changed = true;
+    }
+    Unlock();
+
+    if (enable && changed)
+      Signal();
+  }
+
+  int value;
+
+ private:
+  bool enabled_;
+};
+
+struct WorkerTest : public testing::Test {
+  TestWorker worker;
+
+  virtual void SetUp() {
+    worker.Init();
+  }
+
+  void small_delay() {
+    std::this_thread::sleep_for(std::chrono::milliseconds(20));
+  }
+};
+
+TEST_F(WorkerTest, test_worker) {
+  // already isInitialized so should fail
+  ASSERT_TRUE(worker.initialized());
+
+  int val = worker.value;
+  small_delay();
+
+  // value shouldn't change when isInitialized
+  ASSERT_EQ(val, worker.value);
+
+  worker.Control(true);
+  small_delay();
+
+  // while locked, value shouldn't be changing
+  worker.Lock();
+  val = worker.value;
+  small_delay();
+  ASSERT_EQ(val, worker.value);
+  worker.Unlock();
+
+  small_delay();
+  // value should be different now
+  ASSERT_NE(val, worker.value);
+
+  worker.Control(false);
+  worker.Lock();
+  val = worker.value;
+  worker.Unlock();
+  small_delay();
+
+  // value should be same
+  ASSERT_EQ(val, worker.value);
+
+  worker.Exit();
+  ASSERT_FALSE(worker.initialized());
+}
+
+TEST_F(WorkerTest, exit_while_running) {
+  worker.Control(true);
+
+  std::this_thread::sleep_for(std::chrono::milliseconds(50));
+  worker.Exit();
+}