diff --git a/gnss/2.1/default/GnssConfiguration.h b/gnss/2.1/default/GnssConfiguration.h
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+++ b/gnss/2.1/default/GnssConfiguration.h
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+/*
+ * Copyright (C) 2019 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.
+ */
+
+#ifndef ANDROID_HARDWARE_GNSS_V2_1_GNSSCONFIGURATION_H
+#define ANDROID_HARDWARE_GNSS_V2_1_GNSSCONFIGURATION_H
+
+#include <android/hardware/gnss/2.1/IGnssCallback.h>
+#include <android/hardware/gnss/2.1/IGnssConfiguration.h>
+#include <hidl/MQDescriptor.h>
+#include <hidl/Status.h>
+#include <mutex>
+#include <unordered_set>
+
+namespace android {
+namespace hardware {
+namespace gnss {
+namespace V2_1 {
+namespace implementation {
+
+using ::android::sp;
+using ::android::hardware::hidl_array;
+using ::android::hardware::hidl_memory;
+using ::android::hardware::hidl_string;
+using ::android::hardware::hidl_vec;
+using ::android::hardware::Return;
+using ::android::hardware::Void;
+
+using BlacklistedSourceV2_1 =
+        ::android::hardware::gnss::V2_1::IGnssConfiguration::BlacklistedSource;
+using GnssConstellationTypeV2_0 = V2_0::GnssConstellationType;
+using GnssSvInfoV2_1 = V2_1::IGnssCallback::GnssSvInfo;
+
+struct BlacklistedSourceHashV2_1 {
+    inline int operator()(const BlacklistedSourceV2_1& source) const {
+        return int(source.constellation) * 1000 + int(source.svid);
+    }
+};
+
+struct BlacklistedSourceEqualV2_1 {
+    inline bool operator()(const BlacklistedSourceV2_1& s1, const BlacklistedSourceV2_1& s2) const {
+        return (s1.constellation == s2.constellation) && (s1.svid == s2.svid);
+    }
+};
+
+using BlacklistedSourceSetV2_1 =
+        std::unordered_set<BlacklistedSourceV2_1, BlacklistedSourceHashV2_1,
+                           BlacklistedSourceEqualV2_1>;
+using BlacklistedConstellationSetV2_1 = std::unordered_set<GnssConstellationTypeV2_0>;
+
+struct GnssConfiguration : public IGnssConfiguration {
+    // Methods from ::android::hardware::gnss::V1_0::IGnssConfiguration follow.
+    Return<bool> setSuplEs(bool enabled) override;
+    Return<bool> setSuplVersion(uint32_t version) override;
+    Return<bool> setSuplMode(hidl_bitfield<SuplMode> mode) override;
+    Return<bool> setGpsLock(hidl_bitfield<GpsLock> lock) override;
+    Return<bool> setLppProfile(hidl_bitfield<LppProfile> lppProfile) override;
+    Return<bool> setGlonassPositioningProtocol(hidl_bitfield<GlonassPosProtocol> protocol) override;
+    Return<bool> setEmergencySuplPdn(bool enable) override;
+
+    // Methods from ::android::hardware::gnss::V1_1::IGnssConfiguration follow.
+    Return<bool> setBlacklist(
+            const hidl_vec<V1_1::IGnssConfiguration::BlacklistedSource>& blacklist) override;
+
+    std::recursive_mutex& getMutex() const;
+
+    // Methods from ::android::hardware::gnss::V2_0::IGnssConfiguration follow.
+    Return<bool> setEsExtensionSec(uint32_t emergencyExtensionSeconds) override;
+
+    // Methods from ::android::hardware::gnss::V2_1::IGnssConfiguration follow.
+    Return<bool> setBlacklist_2_1(
+            const hidl_vec<V2_1::IGnssConfiguration::BlacklistedSource>& blacklist) override;
+
+    Return<bool> isBlacklistedV2_1(const GnssSvInfoV2_1& gnssSvInfo) const;
+
+  private:
+    mutable std::recursive_mutex mMutex;
+
+    BlacklistedSourceSetV2_1 mBlacklistedSourceSet;
+    BlacklistedConstellationSetV2_1 mBlacklistedConstellationSet;
+};
+
+}  // namespace implementation
+}  // namespace V2_1
+}  // namespace gnss
+}  // namespace hardware
+}  // namespace android
+
+#endif  // ANDROID_HARDWARE_GNSS_V2_1_GNSSCONFIGURATION_H
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