hidl: biometrics: fingerprint: Add surfaceflinger extension lib

Change-Id: I51fb56c0a20e3cac83afb46ed6a6e2f967159d18

hidl/biometrics/fingerprint/Android.bp

@@ -38,3 +38,14 @@ cc_library_headers {
     header_libs: ["libhardware_headers"],
     export_header_lib_headers: ["libhardware_headers"],
 }
+
+cc_library_static {
+    name: "libudfps_extension.xiaomi",
+    srcs: ["UdfpsExtension.cpp"],
+    include_dirs: [
+        "frameworks/native/services/surfaceflinger/CompositionEngine/include"
+    ],
+    header_libs: [
+        "generated_kernel_headers",
+    ],
+}

hidl/biometrics/fingerprint/UdfpsExtension.cpp

@@ -0,0 +1,19 @@
+/*
+ * Copyright (C) 2022 The LineageOS Project
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <compositionengine/UdfpsExtension.h>
+#include <drm/sde_drm.h>
+
+uint32_t getUdfpsZOrder(uint32_t z, bool touched) {
+    if (touched) {
+        z |= FOD_PRESSED_LAYER_ZORDER;
+    }
+    return z;
+}
+
+uint64_t getUdfpsUsageBits(uint64_t usageBits, bool /* touched */) {
+    return usageBits;
+}