libaudiohal: Implement simple HIDL client

This client requires both HIDL client and server to be of the same
ABI version (e.g. 32-bit).

EffectHalHidl::process and EffectHalHidl::processReverse are stubs.

Some extra warnings are logged due to unimplemented functions
in the legacy HAL.

Bug: 30222631
Change-Id: Id074131dec6d6c4f1031695abcf3ea066e92a5af
Test: Play Music (play / EQ), YouTube, Loopback RTLT, Ok Google on N5X
diff --git a/media/libaudiohal/DevicesFactoryHalHidl.cpp b/media/libaudiohal/DevicesFactoryHalHidl.cpp
new file mode 100644
index 0000000..155b1a8
--- /dev/null
+++ b/media/libaudiohal/DevicesFactoryHalHidl.cpp
@@ -0,0 +1,88 @@
+/*
+ * 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.
+ */
+
+#include <string.h>
+
+#define LOG_TAG "DevicesFactoryHalHidl"
+//#define LOG_NDEBUG 0
+
+#include <android/hardware/audio/2.0/IDevice.h>
+#include <utils/Log.h>
+
+#include "DeviceHalHidl.h"
+#include "DevicesFactoryHalHidl.h"
+
+using ::android::hardware::audio::V2_0::IDevice;
+using ::android::hardware::audio::V2_0::Result;
+using ::android::hardware::Return;
+using ::android::hardware::Status;
+
+namespace android {
+
+// static
+sp<DevicesFactoryHalInterface> DevicesFactoryHalInterface::create() {
+    return new DevicesFactoryHalHidl();
+}
+
+DevicesFactoryHalHidl::DevicesFactoryHalHidl() {
+    mDevicesFactory = IDevicesFactory::getService("audio_devices_factory");
+}
+
+DevicesFactoryHalHidl::~DevicesFactoryHalHidl() {
+}
+
+// static
+status_t DevicesFactoryHalHidl::nameFromHal(const char *name, IDevicesFactory::Device *device) {
+    if (strcmp(name, AUDIO_HARDWARE_MODULE_ID_PRIMARY) == 0) {
+        *device = IDevicesFactory::Device::PRIMARY;
+        return OK;
+    } else if(strcmp(name, AUDIO_HARDWARE_MODULE_ID_A2DP) == 0) {
+        *device = IDevicesFactory::Device::A2DP;
+        return OK;
+    } else if(strcmp(name, AUDIO_HARDWARE_MODULE_ID_USB) == 0) {
+        *device = IDevicesFactory::Device::USB;
+        return OK;
+    } else if(strcmp(name, AUDIO_HARDWARE_MODULE_ID_REMOTE_SUBMIX) == 0) {
+        *device = IDevicesFactory::Device::R_SUBMIX;
+        return OK;
+    }
+    ALOGE("Invalid device name %s", name);
+    return BAD_VALUE;
+}
+
+status_t DevicesFactoryHalHidl::openDevice(const char *name, sp<DeviceHalInterface> *device) {
+    if (mDevicesFactory == 0) return NO_INIT;
+    IDevicesFactory::Device hidlDevice;
+    status_t status = nameFromHal(name, &hidlDevice);
+    if (status != OK) return status;
+    Result retval = Result::NOT_INITIALIZED;
+    Return<void> ret = mDevicesFactory->openDevice(
+            hidlDevice,
+            [&](Result r, const sp<IDevice>& result) {
+                retval = r;
+                if (retval == Result::OK) {
+                    *device = new DeviceHalHidl(result);
+                }
+            });
+    if (ret.getStatus().isOk()) {
+        if (retval == Result::OK) return OK;
+        else if (retval == Result::INVALID_ARGUMENTS) return BAD_VALUE;
+        else return NO_INIT;
+    }
+    return ret.getStatus().transactionError();
+}
+
+} // namespace android