power: Add support for tap-to-wake feature control

Change-Id: I545902b29f4828c127bc32def6e30b67ce4a3aa7
diff --git a/Power.cpp b/Power.cpp
index 11e0c21..ebdc60a 100644
--- a/Power.cpp
+++ b/Power.cpp
@@ -29,6 +29,7 @@
 
 #define LOG_TAG "QTI PowerHAL"
 
+#include <android-base/file.h>
 #include <log/log.h>
 #include "Power.h"
 #include "power-common.h"
@@ -64,6 +65,15 @@
 }
 
 Return<void> Power::setFeature(Feature feature, bool activate)  {
+    switch (feature) {
+#ifdef TAP_TO_WAKE_NODE
+        case Feature::POWER_FEATURE_DOUBLE_TAP_TO_WAKE:
+            ::android::base::WriteStringToFile(activate ? "1" : "0", TAP_TO_WAKE_NODE);
+            break;
+#endif
+        default:
+            break;
+    }
     return Void();
 }