Audio HAL V7.1: Add latency mode APIs am: ed7dfd5f35 am: 27f68d69e8

Original change: https://android-review.googlesource.com/c/platform/hardware/interfaces/+/1975128

Change-Id: Id59b47ddf04b004ce753ca39bef15df37daa6bbf
diff --git a/audio/7.1/Android.bp b/audio/7.1/Android.bp
index d0d96b6..52980e2 100644
--- a/audio/7.1/Android.bp
+++ b/audio/7.1/Android.bp
@@ -13,11 +13,13 @@
     name: "android.hardware.audio@7.1",
     root: "android.hardware",
     srcs: [
+        "types.hal",
         "IDevice.hal",
         "IDevicesFactory.hal",
         "IPrimaryDevice.hal",
         "IStreamIn.hal",
         "IStreamOut.hal",
+        "IStreamOutLatencyModeCallback.hal",
     ],
     interfaces: [
         "android.hardware.audio@7.0",
diff --git a/audio/7.1/IStreamOut.hal b/audio/7.1/IStreamOut.hal
index 092a9a0..b2013cf 100644
--- a/audio/7.1/IStreamOut.hal
+++ b/audio/7.1/IStreamOut.hal
@@ -16,7 +16,54 @@
 
 package android.hardware.audio@7.1;
 
+import @7.0::Result;
 import @7.0::IStreamOut;
 
+import IStreamOutLatencyModeCallback;
+
 interface IStreamOut extends @7.0::IStreamOut {
+    /**
+     * Indicates the requested latency mode for this output stream.
+     *
+     * The requested mode can be one of the modes returned by
+     * getRecommendedLatencyModes() API.
+     *
+     * Optional method.
+     * Mandated only on specific spatial audio streams indicated by
+     * AUDIO_OUTPUT_FLAG_SPATIALIZER flag if they can be routed to a BT classic sink.
+     *
+     * @return retval operation completion status.
+     */
+    setLatencyMode(LatencyMode mode) generates (Result retval);
+
+    /**
+     * 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.
+     *
+     * Optional method.
+     * Mandated only on specific spatial audio streams indicated by
+     * AUDIO_OUTPUT_FLAG_SPATIALIZER flag if they can be routed to a BT classic sink.
+     *
+     * @return retval operation completion status.
+     * @return modes currrently supported latency modes.
+     */
+    getRecommendedLatencyModes() generates (Result retval, vec<LatencyMode> modes);
+
+    /**
+     * Set the callback interface for notifying changes in supported latency modes.
+     *
+     * Calling this method with a null pointer will result in releasing
+     * the callback.
+     *
+     * Optional method.
+     * Mandated only on specific spatial audio streams indicated by
+     * AUDIO_OUTPUT_FLAG_SPATIALIZER flag if they can be routed to a BT classic sink.
+     *
+     * @return retval operation completion status.
+     */
+    setLatencyModeCallback(IStreamOutLatencyModeCallback callback) generates (Result retval);
 };
diff --git a/audio/7.1/IStreamOutLatencyModeCallback.hal b/audio/7.1/IStreamOutLatencyModeCallback.hal
new file mode 100644
index 0000000..45b453f
--- /dev/null
+++ b/audio/7.1/IStreamOutLatencyModeCallback.hal
@@ -0,0 +1,28 @@
+/*
+ * Copyright (C) 2022 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.
+ */
+
+
+package android.hardware.audio@7.1;
+
+/**
+ * Callback interface for output stream variable latency mode feature.
+ */
+interface IStreamOutLatencyModeCallback {
+    /**
+     * Called with the new list of supported latency modes when a change occurs.
+     */
+    oneway onRecommendedLatencyModeChanged(vec<LatencyMode> modes);
+};
diff --git a/audio/7.1/types.hal b/audio/7.1/types.hal
new file mode 100644
index 0000000..9d8ee4d
--- /dev/null
+++ b/audio/7.1/types.hal
@@ -0,0 +1,30 @@
+/*
+ * Copyright (C) 2022 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.
+ */
+
+package android.hardware.audio@7.1;
+
+/**
+ * Latency modes used for the variable latency feature on output streams.
+ * Used by setLatencyMode() and getRecommendedLatencyModes() methods.
+ */
+
+@export(name="audio_latency_mode_t", value_prefix="AUDIO_LATENCY_MODE_")
+enum LatencyMode : int32_t {
+    /** No specific constraint on the latency */
+    FREE = 0,
+    /** A relatively low latency compatible with head tracking operation (e.g less than 100ms) */
+    LOW = 1,
+};
diff --git a/audio/core/all-versions/default/StreamOut.cpp b/audio/core/all-versions/default/StreamOut.cpp
index d4a89d7..09df4ed 100644
--- a/audio/core/all-versions/default/StreamOut.cpp
+++ b/audio/core/all-versions/default/StreamOut.cpp
@@ -761,6 +761,73 @@
     ALOGW_IF(!result.isOk(), "Client callback failed: %s", result.description().c_str());
     return 0;
 }
+
+#if MAJOR_VERSION == 7 && MINOR_VERSION == 1
+Return<Result> StreamOut::setLatencyMode(LatencyMode mode) {
+    return mStream->set_latency_mode != nullptr
+                   ? Stream::analyzeStatus(
+                             "set_latency_mode",
+                             mStream->set_latency_mode(mStream,
+                                                       static_cast<audio_latency_mode_t>(mode)))
+                   : Result::NOT_SUPPORTED;
+};
+
+Return<void> StreamOut::getRecommendedLatencyModes(getRecommendedLatencyModes_cb _hidl_cb) {
+    Result retval = Result::NOT_SUPPORTED;
+    hidl_vec<LatencyMode> hidlModes;
+    size_t num_modes = AUDIO_LATENCY_MODE_CNT;
+    audio_latency_mode_t modes[AUDIO_LATENCY_MODE_CNT];
+
+    if (mStream->get_recommended_latency_modes != nullptr &&
+        mStream->get_recommended_latency_modes(mStream, &modes[0], &num_modes) == 0) {
+        if (num_modes == 0 || num_modes > AUDIO_LATENCY_MODE_CNT) {
+            ALOGW("%s invalid number of modes returned: %zu", __func__, num_modes);
+            retval = Result::INVALID_STATE;
+        } else {
+            hidlModes.resize(num_modes);
+            for (size_t i = 0; i < num_modes; ++i) {
+                hidlModes[i] = static_cast<LatencyMode>(modes[i]);
+            }
+            retval = Result::OK;
+        }
+    }
+    _hidl_cb(retval, hidlModes);
+    return Void();
+};
+
+// static
+void StreamOut::latencyModeCallback(audio_latency_mode_t* modes, size_t num_modes, void* cookie) {
+    StreamOut* self = reinterpret_cast<StreamOut*>(cookie);
+    sp<IStreamOutLatencyModeCallback> callback = self->mLatencyModeCallback.load();
+    if (callback.get() == nullptr) return;
+
+    ALOGV("%s", __func__);
+
+    if (num_modes == 0 || num_modes > AUDIO_LATENCY_MODE_CNT) {
+        ALOGW("%s invalid number of modes returned: %zu", __func__, num_modes);
+        return;
+    }
+
+    hidl_vec<LatencyMode> hidlModes(num_modes);
+    for (size_t i = 0; i < num_modes; ++i) {
+        hidlModes[i] = static_cast<LatencyMode>(modes[i]);
+    }
+    Return<void> result = callback->onRecommendedLatencyModeChanged(hidlModes);
+    ALOGW_IF(!result.isOk(), "Client callback failed: %s", result.description().c_str());
+}
+
+Return<Result> StreamOut::setLatencyModeCallback(
+        const sp<IStreamOutLatencyModeCallback>& callback) {
+    if (mStream->set_latency_mode_callback == nullptr) return Result::NOT_SUPPORTED;
+    int result = mStream->set_latency_mode_callback(mStream, StreamOut::latencyModeCallback, this);
+    if (result == 0) {
+        mLatencyModeCallback = callback;
+    }
+    return Stream::analyzeStatus("set_latency_mode_callback", result, {ENOSYS} /*ignore*/);
+};
+
+#endif
+
 #endif
 
 }  // namespace implementation
diff --git a/audio/core/all-versions/default/include/core/default/StreamOut.h b/audio/core/all-versions/default/include/core/default/StreamOut.h
index 60ad5d5..ce5253f 100644
--- a/audio/core/all-versions/default/include/core/default/StreamOut.h
+++ b/audio/core/all-versions/default/include/core/default/StreamOut.h
@@ -153,6 +153,12 @@
     Result doUpdateSourceMetadata(const SourceMetadata& sourceMetadata);
 #if MAJOR_VERSION >= 7
     Result doUpdateSourceMetadataV7(const SourceMetadata& sourceMetadata);
+#if MAJOR_VERSION == 7 && MINOR_VERSION == 1
+    Return<Result> setLatencyMode(LatencyMode mode) override;
+    Return<void> getRecommendedLatencyModes(getRecommendedLatencyModes_cb _hidl_cb) override;
+    Return<Result> setLatencyModeCallback(
+            const sp<IStreamOutLatencyModeCallback>& callback) override;
+#endif
 #endif
 #endif  // MAJOR_VERSION >= 4
 
@@ -163,6 +169,9 @@
     mediautils::atomic_sp<IStreamOutCallback> mCallback;  // for non-blocking write and drain
 #if MAJOR_VERSION >= 6
     mediautils::atomic_sp<IStreamOutEventCallback> mEventCallback;
+#if MAJOR_VERSION == 7 && MINOR_VERSION == 1
+    mediautils::atomic_sp<IStreamOutLatencyModeCallback> mLatencyModeCallback;
+#endif
 #endif
     std::unique_ptr<CommandMQ> mCommandMQ;
     std::unique_ptr<DataMQ> mDataMQ;
@@ -177,6 +186,9 @@
 
 #if MAJOR_VERSION >= 6
     static int asyncEventCallback(stream_event_callback_type_t event, void* param, void* cookie);
+#if MAJOR_VERSION == 7 && MINOR_VERSION == 1
+    static void latencyModeCallback(audio_latency_mode_t* modes, size_t num_modes, void* cookie);
+#endif
 #endif
 };