Implement audio devices and streams HAL delegating to legacy HAL

Changes made to the .hal definition:

  - introduce Effect ID returned by the IEffectsFactory that
    needs to be passed to IStream.{add|remove}Effect; otherwise
    it's impossible to retrieve the underlying HAL effect handle;

  - change "bus address" in DeviceAddress to "string" type;

  - fix signature of some methods w.r.t. returning Result;

  - remove unused "struct AudioPatch".

Bug: 30222631
Test: make
Change-Id: Icb51729ef57bb2a5b0b78609735e7481bc04f95c
diff --git a/audio/2.0/default/ParametersUtil.h b/audio/2.0/default/ParametersUtil.h
new file mode 100644
index 0000000..49036dc
--- /dev/null
+++ b/audio/2.0/default/ParametersUtil.h
@@ -0,0 +1,66 @@
+/*
+ * Copyright (C) 2016 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_audio_V2_0_ParametersUtil_H_
+#define android_hardware_audio_V2_0_ParametersUtil_H_
+
+#include <functional>
+#include <memory>
+
+#include <android/hardware/audio/2.0/types.h>
+#include <hidl/HidlSupport.h>
+#include <media/AudioParameter.h>
+
+namespace android {
+namespace hardware {
+namespace audio {
+namespace V2_0 {
+namespace implementation {
+
+using ::android::hardware::audio::V2_0::ParameterValue;
+using ::android::hardware::audio::V2_0::Result;
+using ::android::hardware::hidl_string;
+using ::android::hardware::hidl_vec;
+
+class ParametersUtil {
+  public:
+    Result getParam(const char* name, bool* value);
+    Result getParam(const char* name, int* value);
+    Result getParam(const char* name, String8* value);
+    void getParametersImpl(
+            const hidl_vec<hidl_string>& keys,
+            std::function<void(Result retval, const hidl_vec<ParameterValue>& parameters)> cb);
+    std::unique_ptr<AudioParameter> getParams(const AudioParameter& keys);
+    Result setParam(const char* name, bool value);
+    Result setParam(const char* name, int value);
+    Result setParam(const char* name, const char* value);
+    Result setParametersImpl(const hidl_vec<ParameterValue>& parameters);
+    Result setParams(const AudioParameter& param);
+
+  protected:
+    virtual ~ParametersUtil() {}
+
+    virtual char* halGetParameters(const char* keys) = 0;
+    virtual int halSetParameters(const char* keysAndValues) = 0;
+};
+
+}  // namespace implementation
+}  // namespace V2_0
+}  // namespace audio
+}  // namespace hardware
+}  // namespace android
+
+#endif  // android_hardware_audio_V2_0_ParametersUtil_H_