4 files changed, 735 insertions, 0 deletions
diff --git a/src/audio_core/in/audio_in.cpp b/src/audio_core/in/audio_in.cpp
new file mode 100644
index 000000000..c946895d6
--- /dev/null
+++ b/src/audio_core/in/audio_in.cpp
@@ -0,0 +1,100 @@
+// SPDX-FileCopyrightText: Copyright 2022 yuzu Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include "audio_core/audio_in_manager.h"
+#include "audio_core/in/audio_in.h"
+#include "core/hle/kernel/k_event.h"
+
+namespace AudioCore::AudioIn {
+
+In::In(Core::System& system_, Manager& manager_, Kernel::KEvent* event_, size_t session_id_)
+    : manager{manager_}, parent_mutex{manager.mutex}, event{event_}, system{system_, event,
+                                                                            session_id_} {}
+
+void In::Free() {
+    std::scoped_lock l{parent_mutex};
+    manager.ReleaseSessionId(system.GetSessionId());
+}
+
+System& In::GetSystem() {
+    return system;
+}
+
+AudioIn::State In::GetState() {
+    std::scoped_lock l{parent_mutex};
+    return system.GetState();
+}
+
+Result In::StartSystem() {
+    std::scoped_lock l{parent_mutex};
+    return system.Start();
+}
+
+void In::StartSession() {
+    std::scoped_lock l{parent_mutex};
+    system.StartSession();
+}
+
+Result In::StopSystem() {
+    std::scoped_lock l{parent_mutex};
+    return system.Stop();
+}
+
+Result In::AppendBuffer(const AudioInBuffer& buffer, u64 tag) {
+    std::scoped_lock l{parent_mutex};
+
+    if (system.AppendBuffer(buffer, tag)) {
+        return ResultSuccess;
+    }
+    return Service::Audio::ERR_BUFFER_COUNT_EXCEEDED;
+}
+
+void In::ReleaseAndRegisterBuffers() {
+    std::scoped_lock l{parent_mutex};
+    if (system.GetState() == State::Started) {
+        system.ReleaseBuffers();
+        system.RegisterBuffers();
+    }
+}
+
+bool In::FlushAudioInBuffers() {
+    std::scoped_lock l{parent_mutex};
+    return system.FlushAudioInBuffers();
+}
+
+u32 In::GetReleasedBuffers(std::span<u64> tags) {
+    std::scoped_lock l{parent_mutex};
+    return system.GetReleasedBuffers(tags);
+}
+
+Kernel::KReadableEvent& In::GetBufferEvent() {
+    std::scoped_lock l{parent_mutex};
+    return event->GetReadableEvent();
+}
+
+f32 In::GetVolume() {
+    std::scoped_lock l{parent_mutex};
+    return system.GetVolume();
+}
+
+void In::SetVolume(f32 volume) {
+    std::scoped_lock l{parent_mutex};
+    system.SetVolume(volume);
+}
+
+bool In::ContainsAudioBuffer(u64 tag) {
+    std::scoped_lock l{parent_mutex};
+    return system.ContainsAudioBuffer(tag);
+}
+
+u32 In::GetBufferCount() {
+    std::scoped_lock l{parent_mutex};
+    return system.GetBufferCount();
+}
+
+u64 In::GetPlayedSampleCount() {
+    std::scoped_lock l{parent_mutex};
+    return system.GetPlayedSampleCount();
+}
+
+} // namespace AudioCore::AudioIn
diff --git a/src/audio_core/in/audio_in.h b/src/audio_core/in/audio_in.h
new file mode 100644
index 000000000..6253891d5
--- /dev/null
+++ b/src/audio_core/in/audio_in.h
@@ -0,0 +1,147 @@
+// SPDX-FileCopyrightText: Copyright 2022 yuzu Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#pragma once
+
+#include <mutex>
+
+#include "audio_core/in/audio_in_system.h"
+
+namespace Core {
+class System;
+}
+
+namespace Kernel {
+class KEvent;
+class KReadableEvent;
+} // namespace Kernel
+
+namespace AudioCore::AudioIn {
+class Manager;
+
+/**
+ * Interface between the service and audio in system. Mainly responsible for forwarding service
+ * calls to the system.
+ */
+class In {
+public:
+    explicit In(Core::System& system, Manager& manager, Kernel::KEvent* event, size_t session_id);
+
+    /**
+     * Free this audio in from the audio in manager.
+     */
+    void Free();
+
+    /**
+     * Get this audio in's system.
+     */
+    System& GetSystem();
+
+    /**
+     * Get the current state.
+     *
+     * @return Started or Stopped.
+     */
+    AudioIn::State GetState();
+
+    /**
+     * Start the system
+     *
+     * @return Result code
+     */
+    Result StartSystem();
+
+    /**
+     * Start the system's device session.
+     */
+    void StartSession();
+
+    /**
+     * Stop the system.
+     *
+     * @return Result code
+     */
+    Result StopSystem();
+
+    /**
+     * Append a new buffer to the system, the buffer event will be signalled when it is filled.
+     *
+     * @param buffer - The new buffer to append.
+     * @param tag    - Unique tag for this buffer.
+     * @return Result code.
+     */
+    Result AppendBuffer(const AudioInBuffer& buffer, u64 tag);
+
+    /**
+     * Release all completed buffers, and register any appended.
+     */
+    void ReleaseAndRegisterBuffers();
+
+    /**
+     * Flush all buffers.
+     */
+    bool FlushAudioInBuffers();
+
+    /**
+     * Get all of the currently released buffers.
+     *
+     * @param tags - Output container for the buffer tags which were released.
+     * @return The number of buffers released.
+     */
+    u32 GetReleasedBuffers(std::span<u64> tags);
+
+    /**
+     * Get the buffer event for this audio in, this event will be signalled when a buffer is filled.
+     *
+     * @return The buffer event.
+     */
+    Kernel::KReadableEvent& GetBufferEvent();
+
+    /**
+     * Get the current system volume.
+     *
+     * @return The current volume.
+     */
+    f32 GetVolume();
+
+    /**
+     * Set the system volume.
+     *
+     * @param volume - The volume to set.
+     */
+    void SetVolume(f32 volume);
+
+    /**
+     * Check if a buffer is in the system.
+     *
+     * @param tag - The tag to search for.
+     * @return True if the buffer is in the system, otherwise false.
+     */
+    bool ContainsAudioBuffer(u64 tag);
+
+    /**
+     * Get the maximum number of buffers.
+     *
+     * @return The maximum number of buffers.
+     */
+    u32 GetBufferCount();
+
+    /**
+     * Get the total played sample count for this audio in.
+     *
+     * @return The played sample count.
+     */
+    u64 GetPlayedSampleCount();
+
+private:
+    /// The AudioIn::Manager this audio in is registered with
+    Manager& manager;
+    /// Manager's mutex
+    std::recursive_mutex& parent_mutex;
+    /// Buffer event, signalled when buffers are ready to be released
+    Kernel::KEvent* event;
+    /// Main audio in system
+    System system;
+};
+
+} // namespace AudioCore::AudioIn
diff --git a/src/audio_core/in/audio_in_system.cpp b/src/audio_core/in/audio_in_system.cpp
new file mode 100644
index 000000000..ec5d37ed4
--- /dev/null
+++ b/src/audio_core/in/audio_in_system.cpp
@@ -0,0 +1,213 @@
+// SPDX-FileCopyrightText: Copyright 2022 yuzu Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include <mutex>
+#include "audio_core/audio_event.h"
+#include "audio_core/audio_manager.h"
+#include "audio_core/in/audio_in_system.h"
+#include "common/logging/log.h"
+#include "core/core.h"
+#include "core/core_timing.h"
+#include "core/hle/kernel/k_event.h"
+
+namespace AudioCore::AudioIn {
+
+System::System(Core::System& system_, Kernel::KEvent* event_, const size_t session_id_)
+    : system{system_}, buffer_event{event_},
+      session_id{session_id_}, session{std::make_unique<DeviceSession>(system_)} {}
+
+System::~System() {
+    Finalize();
+}
+
+void System::Finalize() {
+    Stop();
+    session->Finalize();
+    buffer_event->GetWritableEvent().Signal();
+}
+
+void System::StartSession() {
+    session->Start();
+}
+
+size_t System::GetSessionId() const {
+    return session_id;
+}
+
+std::string_view System::GetDefaultDeviceName() {
+    return "BuiltInHeadset";
+}
+
+std::string_view System::GetDefaultUacDeviceName() {
+    return "Uac";
+}
+
+Result System::IsConfigValid(const std::string_view device_name,
+                             const AudioInParameter& in_params) {
+    if ((device_name.size() > 0) &&
+        (device_name != GetDefaultDeviceName() && device_name != GetDefaultUacDeviceName())) {
+        return Service::Audio::ERR_INVALID_DEVICE_NAME;
+    }
+
+    if (in_params.sample_rate != TargetSampleRate && in_params.sample_rate > 0) {
+        return Service::Audio::ERR_INVALID_SAMPLE_RATE;
+    }
+
+    return ResultSuccess;
+}
+
+Result System::Initialize(std::string& device_name, const AudioInParameter& in_params,
+                          const u32 handle_, const u64 applet_resource_user_id_) {
+    auto result{IsConfigValid(device_name, in_params)};
+    if (result.IsError()) {
+        return result;
+    }
+
+    handle = handle_;
+    applet_resource_user_id = applet_resource_user_id_;
+    if (device_name.empty() || device_name[0] == '\0') {
+        name = std::string(GetDefaultDeviceName());
+    } else {
+        name = std::move(device_name);
+    }
+
+    sample_rate = TargetSampleRate;
+    sample_format = SampleFormat::PcmInt16;
+    channel_count = in_params.channel_count <= 2 ? 2 : 6;
+    volume = 1.0f;
+    is_uac = name == "Uac";
+    return ResultSuccess;
+}
+
+Result System::Start() {
+    if (state != State::Stopped) {
+        return Service::Audio::ERR_OPERATION_FAILED;
+    }
+
+    session->Initialize(name, sample_format, channel_count, session_id, handle,
+                        applet_resource_user_id, Sink::StreamType::In);
+    session->SetVolume(volume);
+    session->Start();
+    state = State::Started;
+
+    std::vector<AudioBuffer> buffers_to_flush{};
+    buffers.RegisterBuffers(buffers_to_flush);
+    session->AppendBuffers(buffers_to_flush);
+
+    return ResultSuccess;
+}
+
+Result System::Stop() {
+    if (state == State::Started) {
+        session->Stop();
+        session->SetVolume(0.0f);
+        state = State::Stopped;
+    }
+
+    return ResultSuccess;
+}
+
+bool System::AppendBuffer(const AudioInBuffer& buffer, const u64 tag) {
+    if (buffers.GetTotalBufferCount() == BufferCount) {
+        return false;
+    }
+
+    AudioBuffer new_buffer{
+        .played_timestamp = 0, .samples = buffer.samples, .tag = tag, .size = buffer.size};
+
+    buffers.AppendBuffer(new_buffer);
+    RegisterBuffers();
+
+    return true;
+}
+
+void System::RegisterBuffers() {
+    if (state == State::Started) {
+        std::vector<AudioBuffer> registered_buffers{};
+        buffers.RegisterBuffers(registered_buffers);
+        session->AppendBuffers(registered_buffers);
+    }
+}
+
+void System::ReleaseBuffers() {
+    bool signal{buffers.ReleaseBuffers(system.CoreTiming(), *session)};
+
+    if (signal) {
+        // Signal if any buffer was released, or if none are registered, we need more.
+        buffer_event->GetWritableEvent().Signal();
+    }
+}
+
+u32 System::GetReleasedBuffers(std::span<u64> tags) {
+    return buffers.GetReleasedBuffers(tags);
+}
+
+bool System::FlushAudioInBuffers() {
+    if (state != State::Started) {
+        return false;
+    }
+
+    u32 buffers_released{};
+    buffers.FlushBuffers(buffers_released);
+
+    if (buffers_released > 0) {
+        buffer_event->GetWritableEvent().Signal();
+    }
+    return true;
+}
+
+u16 System::GetChannelCount() const {
+    return channel_count;
+}
+
+u32 System::GetSampleRate() const {
+    return sample_rate;
+}
+
+SampleFormat System::GetSampleFormat() const {
+    return sample_format;
+}
+
+State System::GetState() {
+    switch (state) {
+    case State::Started:
+    case State::Stopped:
+        return state;
+    default:
+        LOG_ERROR(Service_Audio, "AudioIn invalid state!");
+        state = State::Stopped;
+        break;
+    }
+    return state;
+}
+
+std::string System::GetName() const {
+    return name;
+}
+
+f32 System::GetVolume() const {
+    return volume;
+}
+
+void System::SetVolume(const f32 volume_) {
+    volume = volume_;
+    session->SetVolume(volume_);
+}
+
+bool System::ContainsAudioBuffer(const u64 tag) {
+    return buffers.ContainsBuffer(tag);
+}
+
+u32 System::GetBufferCount() {
+    return buffers.GetAppendedRegisteredCount();
+}
+
+u64 System::GetPlayedSampleCount() const {
+    return session->GetPlayedSampleCount();
+}
+
+bool System::IsUac() const {
+    return is_uac;
+}
+
+} // namespace AudioCore::AudioIn
diff --git a/src/audio_core/in/audio_in_system.h b/src/audio_core/in/audio_in_system.h
new file mode 100644
index 000000000..165e35d83
--- /dev/null
+++ b/src/audio_core/in/audio_in_system.h
@@ -0,0 +1,275 @@
+// SPDX-FileCopyrightText: Copyright 2022 yuzu Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#pragma once
+
+#include <atomic>
+#include <memory>
+#include <span>
+#include <string>
+
+#include "audio_core/common/common.h"
+#include "audio_core/device/audio_buffers.h"
+#include "audio_core/device/device_session.h"
+#include "core/hle/service/audio/errors.h"
+
+namespace Core {
+class System;
+}
+
+namespace Kernel {
+class KEvent;
+}
+
+namespace AudioCore::AudioIn {
+
+constexpr SessionTypes SessionType = SessionTypes::AudioIn;
+
+struct AudioInParameter {
+    /* 0x0 */ s32_le sample_rate;
+    /* 0x4 */ u16_le channel_count;
+    /* 0x6 */ u16_le reserved;
+};
+static_assert(sizeof(AudioInParameter) == 0x8, "AudioInParameter is an invalid size");
+
+struct AudioInParameterInternal {
+    /* 0x0 */ u32_le sample_rate;
+    /* 0x4 */ u32_le channel_count;
+    /* 0x8 */ u32_le sample_format;
+    /* 0xC */ u32_le state;
+};
+static_assert(sizeof(AudioInParameterInternal) == 0x10,
+              "AudioInParameterInternal is an invalid size");
+
+struct AudioInBuffer {
+    /* 0x00 */ AudioInBuffer* next;
+    /* 0x08 */ VAddr samples;
+    /* 0x10 */ u64 capacity;
+    /* 0x18 */ u64 size;
+    /* 0x20 */ u64 offset;
+};
+static_assert(sizeof(AudioInBuffer) == 0x28, "AudioInBuffer is an invalid size");
+
+enum class State {
+    Started,
+    Stopped,
+};
+
+/**
+ * Controls and drives audio input.
+ */
+class System {
+public:
+    explicit System(Core::System& system, Kernel::KEvent* event, size_t session_id);
+    ~System();
+
+    /**
+     * Get the default audio input device name.
+     *
+     * @return The default audio input device name.
+     */
+    std::string_view GetDefaultDeviceName();
+
+    /**
+     * Get the default USB audio input device name.
+     * This is preferred over non-USB as some games refuse to work with the BuiltInHeadset
+     * (e.g Let's Sing).
+     *
+     * @return The default USB audio input device name.
+     */
+    std::string_view GetDefaultUacDeviceName();
+
+    /**
+     * Is the given initialize config valid?
+     *
+     * @param device_name - The name of the requested input device.
+     * @param in_params   - Input parameters, see AudioInParameter.
+     * @return Result code.
+     */
+    Result IsConfigValid(std::string_view device_name, const AudioInParameter& in_params);
+
+    /**
+     * Initialize this system.
+     *
+     * @param device_name             - The name of the requested input device.
+     * @param in_params               - Input parameters, see AudioInParameter.
+     * @param handle                  - Unused.
+     * @param applet_resource_user_id - Unused.
+     * @return Result code.
+     */
+    Result Initialize(std::string& device_name, const AudioInParameter& in_params, u32 handle,
+                      u64 applet_resource_user_id);
+
+    /**
+     * Start this system.
+     *
+     * @return Result code.
+     */
+    Result Start();
+
+    /**
+     * Stop this system.
+     *
+     * @return Result code.
+     */
+    Result Stop();
+
+    /**
+     * Finalize this system.
+     */
+    void Finalize();
+
+    /**
+     * Start this system's device session.
+     */
+    void StartSession();
+
+    /**
+     * Get this system's id.
+     */
+    size_t GetSessionId() const;
+
+    /**
+     * Append a new buffer to the device.
+     *
+     * @param buffer - New buffer to append.
+     * @param tag    - Unique tag of the buffer.
+     * @return True if the buffer was appended, otherwise false.
+     */
+    bool AppendBuffer(const AudioInBuffer& buffer, u64 tag);
+
+    /**
+     * Register all appended buffers.
+     */
+    void RegisterBuffers();
+
+    /**
+     * Release all registered buffers.
+     */
+    void ReleaseBuffers();
+
+    /**
+     * Get all released buffers.
+     *
+     * @param tags - Container to be filled with the released buffers' tags.
+     * @return The number of buffers released.
+     */
+    u32 GetReleasedBuffers(std::span<u64> tags);
+
+    /**
+     * Flush all appended and registered buffers.
+     *
+     * @return True if buffers were successfully flushed, otherwise false.
+     */
+    bool FlushAudioInBuffers();
+
+    /**
+     * Get this system's current channel count.
+     *
+     * @return The channel count.
+     */
+    u16 GetChannelCount() const;
+
+    /**
+     * Get this system's current sample rate.
+     *
+     * @return The sample rate.
+     */
+    u32 GetSampleRate() const;
+
+    /**
+     * Get this system's current sample format.
+     *
+     * @return The sample format.
+     */
+    SampleFormat GetSampleFormat() const;
+
+    /**
+     * Get this system's current state.
+     *
+     * @return The current state.
+     */
+    State GetState();
+
+    /**
+     * Get this system's name.
+     *
+     * @return The system's name.
+     */
+    std::string GetName() const;
+
+    /**
+     * Get this system's current volume.
+     *
+     * @return The system's current volume.
+     */
+    f32 GetVolume() const;
+
+    /**
+     * Set this system's current volume.
+     *
+     * @param The new volume.
+     */
+    void SetVolume(f32 volume);
+
+    /**
+     * Does the system contain this buffer?
+     *
+     * @param tag - Unique tag to search for.
+     * @return True if the buffer is in the system, otherwise false.
+     */
+    bool ContainsAudioBuffer(u64 tag);
+
+    /**
+     * Get the maximum number of usable buffers (default 32).
+     *
+     * @return The number of buffers.
+     */
+    u32 GetBufferCount();
+
+    /**
+     * Get the total number of samples played by this system.
+     *
+     * @return The number of samples.
+     */
+    u64 GetPlayedSampleCount() const;
+
+    /**
+     * Is this system using a USB device?
+     *
+     * @return True if using a USB device, otherwise false.
+     */
+    bool IsUac() const;
+
+private:
+    /// Core system
+    Core::System& system;
+    /// (Unused)
+    u32 handle{};
+    /// (Unused)
+    u64 applet_resource_user_id{};
+    /// Buffer event, signalled when a buffer is ready
+    Kernel::KEvent* buffer_event;
+    /// Session id of this system
+    size_t session_id{};
+    /// Device session for this system
+    std::unique_ptr<DeviceSession> session;
+    /// Audio buffers in use by this system
+    AudioBuffers<BufferCount> buffers{BufferCount};
+    /// Sample rate of this system
+    u32 sample_rate{};
+    /// Sample format of this system
+    SampleFormat sample_format{SampleFormat::PcmInt16};
+    /// Channel count of this system
+    u16 channel_count{};
+    /// State of this system
+    std::atomic<State> state{State::Stopped};
+    /// Name of this system
+    std::string name{};
+    /// Volume of this system
+    f32 volume{1.0f};
+    /// Is this system's device USB?
+    bool is_uac{false};
+};
+
+} // namespace AudioCore::AudioIn