AHAL: support volume control for USB audio HAL.

Use mixer control to support master mute, master volume and hardware
volume for USB audio HAL.

Bug: 266216550
Test: atest VtsHalAudioCoreTargetTest
Change-Id: Iad544ba517cbfc778ebdf96dd161944886383b73
diff --git a/audio/aidl/default/usb/UsbAlsaMixerControl.cpp b/audio/aidl/default/usb/UsbAlsaMixerControl.cpp
new file mode 100644
index 0000000..b5337d1
--- /dev/null
+++ b/audio/aidl/default/usb/UsbAlsaMixerControl.cpp
@@ -0,0 +1,239 @@
+/*
+ * Copyright (C) 2023 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.
+ */
+
+#define LOG_TAG "AHAL_UsbAlsaMixerControl"
+#include <android-base/logging.h>
+
+#include <cmath>
+#include <string>
+#include <vector>
+
+#include <android/binder_status.h>
+
+#include "UsbAlsaMixerControl.h"
+
+namespace aidl::android::hardware::audio::core::usb {
+
+//-----------------------------------------------------------------------------
+
+MixerControl::MixerControl(struct mixer_ctl* ctl)
+    : mCtl(ctl),
+      mNumValues(mixer_ctl_get_num_values(ctl)),
+      mMinValue(mixer_ctl_get_range_min(ctl)),
+      mMaxValue(mixer_ctl_get_range_max(ctl)) {}
+
+unsigned int MixerControl::getNumValues() const {
+    return mNumValues;
+}
+
+int MixerControl::getMaxValue() const {
+    return mMaxValue;
+}
+
+int MixerControl::getMinValue() const {
+    return mMinValue;
+}
+
+int MixerControl::setArray(const void* array, size_t count) {
+    const std::lock_guard guard(mLock);
+    return mixer_ctl_set_array(mCtl, array, count);
+}
+
+//-----------------------------------------------------------------------------
+
+// static
+const std::map<AlsaMixer::Control, std::vector<AlsaMixer::ControlNamesAndExpectedCtlType>>
+        AlsaMixer::kPossibleControls = {
+                {AlsaMixer::MASTER_SWITCH, {{"Master Playback Switch", MIXER_CTL_TYPE_BOOL}}},
+                {AlsaMixer::MASTER_VOLUME, {{"Master Playback Volume", MIXER_CTL_TYPE_INT}}},
+                {AlsaMixer::HW_VOLUME,
+                 {{"Headphone Playback Volume", MIXER_CTL_TYPE_INT},
+                  {"Headset Playback Volume", MIXER_CTL_TYPE_INT},
+                  {"PCM Playback Volume", MIXER_CTL_TYPE_INT}}}};
+
+// static
+std::map<AlsaMixer::Control, std::shared_ptr<MixerControl>> AlsaMixer::initializeMixerControls(
+        struct mixer* mixer) {
+    std::map<AlsaMixer::Control, std::shared_ptr<MixerControl>> mixerControls;
+    std::string mixerCtlNames;
+    for (const auto& [control, possibleCtls] : kPossibleControls) {
+        for (const auto& [ctlName, expectedCtlType] : possibleCtls) {
+            struct mixer_ctl* ctl = mixer_get_ctl_by_name(mixer, ctlName.c_str());
+            if (ctl != nullptr && mixer_ctl_get_type(ctl) == expectedCtlType) {
+                mixerControls.emplace(control, std::make_unique<MixerControl>(ctl));
+                if (!mixerCtlNames.empty()) {
+                    mixerCtlNames += ",";
+                }
+                mixerCtlNames += ctlName;
+                break;
+            }
+        }
+    }
+    LOG(DEBUG) << __func__ << ": available mixer control names=[" << mixerCtlNames << "]";
+    return mixerControls;
+}
+
+AlsaMixer::AlsaMixer(struct mixer* mixer)
+    : mMixer(mixer), mMixerControls(initializeMixerControls(mMixer)) {}
+
+AlsaMixer::~AlsaMixer() {
+    mixer_close(mMixer);
+}
+
+namespace {
+
+int volumeFloatToInteger(float fValue, int maxValue, int minValue) {
+    return minValue + std::ceil((maxValue - minValue) * fValue);
+}
+
+float volumeIntegerToFloat(int iValue, int maxValue, int minValue) {
+    if (iValue > maxValue) {
+        return 1.0f;
+    }
+    if (iValue < minValue) {
+        return 0.0f;
+    }
+    return static_cast<float>(iValue - minValue) / (maxValue - minValue);
+}
+
+}  // namespace
+
+ndk::ScopedAStatus AlsaMixer::setMasterMute(bool muted) {
+    auto it = mMixerControls.find(AlsaMixer::MASTER_SWITCH);
+    if (it == mMixerControls.end()) {
+        return ndk::ScopedAStatus::fromExceptionCode(EX_UNSUPPORTED_OPERATION);
+    }
+    const int numValues = it->second->getNumValues();
+    std::vector<int> values(numValues, muted ? 0 : 1);
+    if (int err = it->second->setArray(values.data(), numValues); err != 0) {
+        LOG(ERROR) << __func__ << ": failed to set master mute, err=" << err;
+        return ndk::ScopedAStatus::fromExceptionCode(EX_ILLEGAL_STATE);
+    }
+    return ndk::ScopedAStatus::ok();
+}
+
+ndk::ScopedAStatus AlsaMixer::setMasterVolume(float volume) {
+    auto it = mMixerControls.find(AlsaMixer::MASTER_VOLUME);
+    if (it == mMixerControls.end()) {
+        return ndk::ScopedAStatus::fromExceptionCode(EX_UNSUPPORTED_OPERATION);
+    }
+    const int numValues = it->second->getNumValues();
+    std::vector<int> values(numValues, volumeFloatToInteger(volume, it->second->getMaxValue(),
+                                                            it->second->getMinValue()));
+    if (int err = it->second->setArray(values.data(), numValues); err != 0) {
+        LOG(ERROR) << __func__ << ": failed to set master volume, err=" << err;
+        return ndk::ScopedAStatus::fromExceptionCode(EX_ILLEGAL_STATE);
+    }
+    return ndk::ScopedAStatus::ok();
+}
+
+ndk::ScopedAStatus AlsaMixer::setVolumes(std::vector<float> volumes) {
+    auto it = mMixerControls.find(AlsaMixer::HW_VOLUME);
+    if (it == mMixerControls.end()) {
+        return ndk::ScopedAStatus::fromExceptionCode(EX_UNSUPPORTED_OPERATION);
+    }
+    const int numValues = it->second->getNumValues();
+    const int maxValue = it->second->getMaxValue();
+    const int minValue = it->second->getMinValue();
+    std::vector<int> values;
+    size_t i = 0;
+    for (; i < numValues && i < values.size(); ++i) {
+        values.emplace_back(volumeFloatToInteger(volumes[i], maxValue, minValue));
+    }
+    if (int err = it->second->setArray(values.data(), values.size()); err != 0) {
+        LOG(ERROR) << __func__ << ": failed to set volume, err=" << err;
+        return ndk::ScopedAStatus::fromExceptionCode(EX_ILLEGAL_STATE);
+    }
+    return ndk::ScopedAStatus::ok();
+}
+
+//-----------------------------------------------------------------------------
+
+// static
+UsbAlsaMixerControl& UsbAlsaMixerControl::getInstance() {
+    static UsbAlsaMixerControl gInstance;
+    return gInstance;
+}
+
+void UsbAlsaMixerControl::setDeviceConnectionState(int card, bool masterMuted, float masterVolume,
+                                                   bool connected) {
+    LOG(DEBUG) << __func__ << ": card=" << card << ", connected=" << connected;
+    if (connected) {
+        struct mixer* mixer = mixer_open(card);
+        if (mixer == nullptr) {
+            PLOG(ERROR) << __func__ << ": failed to open mixer for card=" << card;
+            return;
+        }
+        auto alsaMixer = std::make_shared<AlsaMixer>(mixer);
+        alsaMixer->setMasterMute(masterMuted);
+        alsaMixer->setMasterVolume(masterVolume);
+        const std::lock_guard guard(mLock);
+        mMixerControls.emplace(card, alsaMixer);
+    } else {
+        const std::lock_guard guard(mLock);
+        mMixerControls.erase(card);
+    }
+}
+
+ndk::ScopedAStatus UsbAlsaMixerControl::setMasterMute(bool mute) {
+    auto alsaMixers = getAlsaMixers();
+    for (auto it = alsaMixers.begin(); it != alsaMixers.end(); ++it) {
+        if (auto result = it->second->setMasterMute(mute); !result.isOk()) {
+            // Return illegal state if there are multiple devices connected and one of them fails
+            // to set master mute. Otherwise, return the error from calling `setMasterMute`.
+            LOG(ERROR) << __func__ << ": failed to set master mute for card=" << it->first;
+            return alsaMixers.size() > 1 ? ndk::ScopedAStatus::fromExceptionCode(EX_ILLEGAL_STATE)
+                                         : std::move(result);
+        }
+    }
+    return ndk::ScopedAStatus::ok();
+}
+
+ndk::ScopedAStatus UsbAlsaMixerControl::setMasterVolume(float volume) {
+    auto alsaMixers = getAlsaMixers();
+    for (auto it = alsaMixers.begin(); it != alsaMixers.end(); ++it) {
+        if (auto result = it->second->setMasterVolume(volume); !result.isOk()) {
+            // Return illegal state if there are multiple devices connected and one of them fails
+            // to set master volume. Otherwise, return the error from calling `setMasterVolume`.
+            LOG(ERROR) << __func__ << ": failed to set master volume for card=" << it->first;
+            return alsaMixers.size() > 1 ? ndk::ScopedAStatus::fromExceptionCode(EX_ILLEGAL_STATE)
+                                         : std::move(result);
+        }
+    }
+    return ndk::ScopedAStatus::ok();
+}
+
+ndk::ScopedAStatus UsbAlsaMixerControl::setVolumes(int card, std::vector<float> volumes) {
+    auto alsaMixer = getAlsaMixer(card);
+    if (alsaMixer == nullptr) {
+        LOG(ERROR) << __func__ << ": no mixer control found for card=" << card;
+        return ndk::ScopedAStatus::fromExceptionCode(EX_UNSUPPORTED_OPERATION);
+    }
+    return alsaMixer->setVolumes(volumes);
+}
+
+std::shared_ptr<AlsaMixer> UsbAlsaMixerControl::getAlsaMixer(int card) {
+    const std::lock_guard guard(mLock);
+    const auto it = mMixerControls.find(card);
+    return it == mMixerControls.end() ? nullptr : it->second;
+}
+
+std::map<int, std::shared_ptr<AlsaMixer>> UsbAlsaMixerControl::getAlsaMixers() {
+    const std::lock_guard guard(mLock);
+    return mMixerControls;
+}
+
+}  // namespace aidl::android::hardware::audio::core::usb