audio HAL V7.1: add latency mode control APIs

Bug: 187446271
Test: make
Change-Id: Ib6ee708d312e4e630637d8b7fb92fda4854590aa
(cherry picked from commit afa586b221a01a345538d7d2d34f836f6cf50730)
Merged-In: Ib6ee708d312e4e630637d8b7fb92fda4854590aa
diff --git a/media/libaudiohal/impl/StreamHalHidl.cpp b/media/libaudiohal/impl/StreamHalHidl.cpp
index 13001bc..7ad4aab 100644
--- a/media/libaudiohal/impl/StreamHalHidl.cpp
+++ b/media/libaudiohal/impl/StreamHalHidl.cpp
@@ -684,6 +684,7 @@
     // Codec format callback is supported starting from audio HAL V6.0
     return INVALID_OPERATION;
 }
+
 #else
 
 status_t StreamOutHalHidl::getDualMonoMode(audio_dual_mono_mode_t* mode) {
@@ -789,6 +790,84 @@
 }
 #endif
 
+#if MAJOR_VERSION == 7 && MINOR_VERSION == 1
+using hardware::audio::V7_1::LatencyMode;
+
+status_t StreamOutHalHidl::setLatencyMode(audio_latency_mode_t mode) {
+    if (mStream == 0) return NO_INIT;
+    return processReturn(
+            "setLatencyMode", mStream->setLatencyMode(static_cast<LatencyMode>(mode)));
+};
+
+status_t StreamOutHalHidl::getRecommendedLatencyModes(std::vector<audio_latency_mode_t> *modes) {
+    if (!mStream) return NO_INIT;
+    Result retval;
+    Return<void> ret = mStream->getRecommendedLatencyModes(
+            [&](Result r, hidl_vec<LatencyMode> hidlModes) {
+        retval = r;
+        for (size_t i = 0; i < hidlModes.size(); i++) {
+            modes->push_back(static_cast<audio_latency_mode_t>(hidlModes[i]));
+        }
+    });
+    return processReturn("getRecommendedLatencyModes", ret, retval);
+};
+
+#include PATH(android/hardware/audio/FILE_VERSION/IStreamOutLatencyModeCallback.h)
+
+using hardware::audio::V7_1::IStreamOutLatencyModeCallback;
+
+namespace {
+struct StreamOutLatencyModeCallback : public IStreamOutLatencyModeCallback {
+    StreamOutLatencyModeCallback(const wp<StreamOutHalHidl>& stream) : mStream(stream) {}
+
+    // IStreamOutLatencyModeCallback implementation
+    Return<void> onRecommendedLatencyModeChanged(const hidl_vec<LatencyMode>& hidlModes) override {
+        sp<StreamOutHalHidl> stream = mStream.promote();
+        if (stream != nullptr) {
+            std::vector<audio_latency_mode_t> modes;
+            for (size_t i = 0; i < hidlModes.size(); i++) {
+                modes.push_back(static_cast<audio_latency_mode_t>(hidlModes[i]));
+            }
+            stream->onRecommendedLatencyModeChanged(modes);
+        }
+        return Void();
+    }
+
+  private:
+    wp<StreamOutHalHidl> mStream;
+};
+}  // namespace
+
+status_t StreamOutHalHidl::setLatencyModeCallback(
+        const sp<StreamOutHalInterfaceLatencyModeCallback>& callback) {
+
+    if (mStream == nullptr) return NO_INIT;
+    mLatencyModeCallback = callback;
+    status_t status = processReturn(
+            "setLatencyModeCallback",
+            mStream->setLatencyModeCallback(
+                    callback.get() == nullptr ? nullptr : new StreamOutLatencyModeCallback(this)));
+    return status;
+};
+
+#else
+
+status_t StreamOutHalHidl::setLatencyMode(audio_latency_mode_t mode __unused) {
+    return INVALID_OPERATION;
+};
+
+status_t StreamOutHalHidl::getRecommendedLatencyModes(
+        std::vector<audio_latency_mode_t> *modes __unused) {
+    return INVALID_OPERATION;
+};
+
+status_t StreamOutHalHidl::setLatencyModeCallback(
+        const sp<StreamOutHalInterfaceLatencyModeCallback>& callback __unused) {
+    return INVALID_OPERATION;
+};
+
+#endif
+
 void StreamOutHalHidl::onWriteReady() {
     sp<StreamOutHalInterfaceCallback> callback = mCallback.load().promote();
     if (callback == 0) return;
@@ -817,6 +896,13 @@
     callback->onCodecFormatChanged(metadataBs);
 }
 
+void StreamOutHalHidl::onRecommendedLatencyModeChanged(
+        const std::vector<audio_latency_mode_t>& modes) {
+    sp<StreamOutHalInterfaceLatencyModeCallback> callback = mLatencyModeCallback.load().promote();
+    if (callback == nullptr) return;
+    callback->onRecommendedLatencyModeChanged(modes);
+}
+
 
 StreamInHalHidl::StreamInHalHidl(
         const sp<::android::hardware::audio::CPP_VERSION::IStreamIn>& stream)
diff --git a/media/libaudiohal/impl/StreamHalHidl.h b/media/libaudiohal/impl/StreamHalHidl.h
index 3405518..4c847da 100644
--- a/media/libaudiohal/impl/StreamHalHidl.h
+++ b/media/libaudiohal/impl/StreamHalHidl.h
@@ -189,6 +189,13 @@
     // Methods used by StreamCodecFormatCallback (HIDL).
     void onCodecFormatChanged(const std::basic_string<uint8_t>& metadataBs);
 
+    status_t setLatencyMode(audio_latency_mode_t mode) override;
+    status_t getRecommendedLatencyModes(std::vector<audio_latency_mode_t> *modes) override;
+    status_t setLatencyModeCallback(
+            const sp<StreamOutHalInterfaceLatencyModeCallback>& callback) override;
+
+    void onRecommendedLatencyModeChanged(const std::vector<audio_latency_mode_t>& modes);
+
   private:
     friend class DeviceHalHidl;
     typedef MessageQueue<WriteCommand, hardware::kSynchronizedReadWrite> CommandMQ;
@@ -197,6 +204,8 @@
 
     mediautils::atomic_wp<StreamOutHalInterfaceCallback> mCallback;
     mediautils::atomic_wp<StreamOutHalInterfaceEventCallback> mEventCallback;
+    mediautils::atomic_wp<StreamOutHalInterfaceLatencyModeCallback> mLatencyModeCallback;
+
     const sp<::android::hardware::audio::CPP_VERSION::IStreamOut> mStream;
     std::unique_ptr<CommandMQ> mCommandMQ;
     std::unique_ptr<DataMQ> mDataMQ;
diff --git a/media/libaudiohal/impl/StreamHalLocal.h b/media/libaudiohal/impl/StreamHalLocal.h
index fd928bb..40d0d6e 100644
--- a/media/libaudiohal/impl/StreamHalLocal.h
+++ b/media/libaudiohal/impl/StreamHalLocal.h
@@ -168,6 +168,18 @@
 
     status_t setEventCallback(const sp<StreamOutHalInterfaceEventCallback>& callback) override;
 
+    status_t setLatencyMode(audio_latency_mode_t mode __unused) override {
+        return INVALID_OPERATION;
+    }
+    status_t getRecommendedLatencyModes(
+            std::vector<audio_latency_mode_t> *modes __unused) override {
+        return INVALID_OPERATION;
+    }
+    status_t setLatencyModeCallback(
+            const sp<StreamOutHalInterfaceLatencyModeCallback>& callback __unused) override {
+        return INVALID_OPERATION;
+    }
+
   private:
     audio_stream_out_t *mStream;
     wp<StreamOutHalInterfaceCallback> mCallback;
diff --git a/media/libaudiohal/include/media/audiohal/StreamHalInterface.h b/media/libaudiohal/include/media/audiohal/StreamHalInterface.h
index 2be12fb..99b38bf 100644
--- a/media/libaudiohal/include/media/audiohal/StreamHalInterface.h
+++ b/media/libaudiohal/include/media/audiohal/StreamHalInterface.h
@@ -116,6 +116,18 @@
     virtual ~StreamOutHalInterfaceEventCallback() {}
 };
 
+class StreamOutHalInterfaceLatencyModeCallback : public virtual RefBase {
+public:
+    /**
+     * Called with the new list of supported latency modes when a change occurs.
+     */
+    virtual void onRecommendedLatencyModeChanged(std::vector<audio_latency_mode_t> modes) = 0;
+
+protected:
+    StreamOutHalInterfaceLatencyModeCallback() {}
+    virtual ~StreamOutHalInterfaceLatencyModeCallback() {}
+};
+
 class StreamOutHalInterface : public virtual StreamHalInterface {
   public:
     // Return the audio hardware driver estimated latency in milliseconds.
@@ -193,6 +205,42 @@
 
     virtual status_t setEventCallback(const sp<StreamOutHalInterfaceEventCallback>& callback) = 0;
 
+    /**
+     * Indicates the requested latency mode for this output stream.
+     *
+     * The requested mode can be one of the modes returned by
+     * getRecommendedLatencyModes() API.
+     *
+     * @param mode the requested latency mode.
+     * @return operation completion status.
+     */
+    virtual status_t setLatencyMode(audio_latency_mode_t mode) = 0;
+
+    /**
+     * Indicates which latency modes are currently supported on this output stream.
+     * If the transport protocol (e.g Bluetooth A2DP) used by this output stream to reach
+     * the output device supports variable latency modes, the HAL indicates which
+     * modes are currently supported.
+     * The framework can then call setLatencyMode() with one of the supported modes to select
+     * the desired operation mode.
+     *
+     * @param modes currrently supported latency modes.
+     * @return operation completion status.
+     */
+    virtual status_t getRecommendedLatencyModes(std::vector<audio_latency_mode_t> *modes) = 0;
+
+    /**
+     * Set the callback interface for notifying changes in supported latency modes.
+     *
+     * Calling this method with a null pointer will result in releasing
+     * the callback.
+     *
+     * @param callback the registered callback or null to unregister.
+     * @return operation completion status.
+     */
+    virtual status_t setLatencyModeCallback(
+            const sp<StreamOutHalInterfaceLatencyModeCallback>& callback) = 0;
+
   protected:
     virtual ~StreamOutHalInterface() {}
 };