Flesh out basic bluetooth support

No ui yet, and performance isn't great. It kinda works though!!

1 files changed, 79 insertions, 0 deletions

diff --git a/src/audio/bt_audio_output.cpp b/src/audio/bt_audio_output.cpp
new file mode 100644
index 00000000..71e40d02
--- /dev/null
+++ b/src/audio/bt_audio_output.cpp
@@ -0,0 +1,79 @@
+/*
+ * Copyright 2023 jacqueline <me@jacqueline.id.au>
+ *
+ * SPDX-License-Identifier: GPL-3.0-only
+ */
+
+#include "bt_audio_output.hpp"
+#include <stdint.h>
+#include <sys/_stdint.h>
+
+#include <algorithm>
+#include <cstddef>
+#include <cstdint>
+#include <memory>
+#include <variant>
+
+#include "esp_err.h"
+#include "esp_heap_caps.h"
+#include "freertos/portmacro.h"
+
+#include "audio_element.hpp"
+#include "freertos/projdefs.h"
+#include "gpios.hpp"
+#include "i2c.hpp"
+#include "i2s_dac.hpp"
+#include "result.hpp"
+#include "stream_info.hpp"
+#include "wm8523.hpp"
+
+static const char* kTag = "BTOUT";
+
+namespace audio {
+
+static constexpr size_t kDrainBufferSize = 48 * 1024;
+
+BluetoothAudioOutput::BluetoothAudioOutput(drivers::Bluetooth* bt)
+    : IAudioSink(kDrainBufferSize, MALLOC_CAP_SPIRAM), bluetooth_(bt) {}
+
+BluetoothAudioOutput::~BluetoothAudioOutput() {}
+
+auto BluetoothAudioOutput::SetInUse(bool in_use) -> void {
+  if (in_use) {
+    bluetooth_->SetSource(stream());
+  } else {
+    bluetooth_->SetSource(nullptr);
+  }
+}
+
+auto BluetoothAudioOutput::SetVolumeImbalance(int_fast8_t balance) -> void {}
+
+auto BluetoothAudioOutput::SetVolume(uint_fast8_t percent) -> void {}
+
+auto BluetoothAudioOutput::GetVolume() -> uint_fast8_t {
+  return 50;
+}
+
+auto BluetoothAudioOutput::AdjustVolumeUp() -> bool {
+  return false;
+}
+
+auto BluetoothAudioOutput::AdjustVolumeDown() -> bool {
+  return false;
+}
+
+auto BluetoothAudioOutput::PrepareFormat(const Format& orig) -> Format {
+  // ESP-IDF's current Bluetooth implementation currently handles SBC encoding,
+  // but requires a fixed input format.
+  return Format{
+      .sample_rate = 44100,
+      .num_channels = 2,
+      .bits_per_sample = 16,
+  };
+}
+
+auto BluetoothAudioOutput::Configure(const Format& fmt) -> void {
+  // No configuration necessary; the output format is fixed.
+}
+
+}  // namespace audio