new pipeline working(?), but the dac eludes me

src/audio/audio_decoder.cpp

@@ -6,6 +6,7 @@
 #include <cstddef>
 #include <cstdint>
 #include <memory>
+#include <variant>
 
 #include "cbor/tinycbor/src/cborinternal_p.h"
 #include "freertos/FreeRTOS.h"
@@ -37,6 +38,7 @@ auto AudioDecoder::ProcessStreamInfo(const StreamInfo& info) -> bool {
   if (!std::holds_alternative<StreamInfo::Encoded>(info.format)) {
     return false;
   }
+  ESP_LOGI(kTag, "got new stream");
   const auto& encoded = std::get<StreamInfo::Encoded>(info.format);
 
   // Reuse the existing codec if we can. This will help with gapless playback,
@@ -45,12 +47,14 @@ auto AudioDecoder::ProcessStreamInfo(const StreamInfo& info) -> bool {
   if (current_codec_ != nullptr &&
       current_codec_->CanHandleType(encoded.type)) {
     current_codec_->ResetForNewStream();
+    ESP_LOGI(kTag, "reusing existing decoder");
     return true;
   }
 
   // TODO: use audio type from stream
   auto result = codecs::CreateCodecForType(encoded.type);
   if (result.has_value()) {
+    ESP_LOGI(kTag, "creating new decoder");
     current_codec_ = std::move(result.value());
   } else {
     ESP_LOGE(kTag, "no codec for this file");
@@ -73,6 +77,9 @@ auto AudioDecoder::Process(const std::vector<InputStream>& inputs,
   }
 
   const StreamInfo& info = input->info();
+  if (std::holds_alternative<std::monostate>(info.format)) {
+    return;
+  }
   if (!current_input_format_ || *current_input_format_ != info.format) {
     // The input stream has changed! Immediately throw everything away and
     // start from scratch.
@@ -100,6 +107,9 @@ auto AudioDecoder::Process(const std::vector<InputStream>& inputs,
       }
 
       auto write_res = current_codec_->WriteOutputSamples(output->data());
+      if (write_res.first > 0) {
+        ESP_LOGI(kTag, "wrote %u bytes of samples", write_res.first);
+      }
       output->add(write_res.first);
       has_samples_to_send_ = !write_res.second;
 

src/audio/audio_playback.cpp

@@ -32,7 +32,8 @@ auto AudioPlayback::create(drivers::GpioExpander* expander)
 }
 
 AudioPlayback::AudioPlayback(std::unique_ptr<I2SAudioOutput> output)
-    : file_source_(), i2s_output_(std::move(output)) {
+    : file_source_(std::make_unique<FatfsAudioInput>()),
+      i2s_output_(std::move(output)) {
   AudioDecoder* codec = new AudioDecoder();
   elements_.emplace_back(codec);
 
@@ -51,7 +52,7 @@ auto AudioPlayback::Play(const std::string& filename) -> void {
 }
 
 auto AudioPlayback::LogStatus() -> void {
-  // TODO.
+  i2s_output_->Log();
 }
 
 }  // namespace audio

src/audio/audio_task.cpp

@@ -7,6 +7,7 @@
 #include <cstdint>
 #include <deque>
 #include <memory>
+#include <variant>
 
 #include "audio_sink.hpp"
 #include "cbor.h"
@@ -114,16 +115,29 @@ void AudioTaskMain(void* args) {
           OutputStream out_stream(&raw_out_stream);
 
           elements.at(i)->OutputElement()->Process(in_streams, &out_stream);
+
+          std::for_each(in_regions.begin(), in_regions.end(),
+                        [](auto&& r) { r.Unmap(); });
+          out_region.Unmap();
         }
 
-        RawStream raw_sink_stream = elements.back()->OutStream(&out_region);
+        RawStream raw_sink_stream = elements.front()->OutStream(&out_region);
         InputStream sink_stream(&raw_sink_stream);
 
-        if (!output_format || output_format != sink_stream.info().format) {
+        if (sink_stream.data().size_bytes() == 0) {
+          out_region.Unmap();
+          vTaskDelay(pdMS_TO_TICKS(100));
+          continue;
+        }
+
+        if ((!output_format || output_format != sink_stream.info().format) &&
+            !std::holds_alternative<std::monostate>(
+                sink_stream.info().format)) {
           // The format of the stream within the sink stream has changed. We
           // need to reconfigure the sink, but shouldn't do so until we've fully
           // drained the current buffer.
           if (xStreamBufferIsEmpty(sink->buffer())) {
+            ESP_LOGI(kTag, "reconfiguring dac");
             output_format = sink_stream.info().format;
             sink->Configure(*output_format);
           }
@@ -140,6 +154,8 @@ void AudioTaskMain(void* args) {
               sink_stream.data().size_bytes(), pdMS_TO_TICKS(10));
           sink_stream.consume(sent);
         }
+
+        out_region.Unmap();
       }
     }
   }

src/audio/fatfs_audio_input.cpp

@@ -65,6 +65,9 @@ auto FatfsAudioInput::Process(const std::vector<InputStream>& inputs,
     return;
   }
 
+  if (size > 0) {
+    ESP_LOGI(kTag, "read %u bytes", size);
+  }
   output->add(size);
 
   if (size < max_size || f_eof(&current_file_)) {

src/audio/i2s_audio_output.cpp

@@ -44,12 +44,14 @@ I2SAudioOutput::~I2SAudioOutput() {}
 
 auto I2SAudioOutput::Configure(const StreamInfo::Format& format) -> bool {
   if (!std::holds_alternative<StreamInfo::Pcm>(format)) {
+    ESP_LOGI(kTag, "ignoring non-pcm stream (%d)", format.index());
     return false;
   }
 
   StreamInfo::Pcm pcm = std::get<StreamInfo::Pcm>(format);
 
   if (current_config_ && pcm == *current_config_) {
+    ESP_LOGI(kTag, "ignoring unchanged format");
     return true;
   }
 
@@ -97,6 +99,10 @@ auto I2SAudioOutput::Send(const cpp::span<std::byte>& data) -> void {
   dac_->WriteData(data);
 }
 
+auto I2SAudioOutput::Log() -> void {
+  dac_->LogStatus();
+}
+
 auto I2SAudioOutput::SetVolume(uint8_t volume) -> void {
   dac_->WriteVolume(volume);
 }

src/audio/include/audio_sink.hpp

@@ -15,6 +15,7 @@ class IAudioSink {
 
   virtual auto Configure(const StreamInfo::Format& format) -> bool = 0;
   virtual auto Send(const cpp::span<std::byte>& data) -> void = 0;
+  virtual auto Log() -> void {}
 
   auto buffer() const -> StreamBufferHandle_t { return buffer_; }
 };

src/audio/include/i2s_audio_output.hpp

@@ -27,6 +27,7 @@ class I2SAudioOutput : public IAudioSink {
 
   auto Configure(const StreamInfo::Format& format) -> bool override;
   auto Send(const cpp::span<std::byte>& data) -> void override;
+  auto Log() -> void override;
 
   I2SAudioOutput(const I2SAudioOutput&) = delete;
   I2SAudioOutput& operator=(const I2SAudioOutput&) = delete;

src/audio/include/stream_info.hpp

@@ -17,12 +17,12 @@ namespace audio {
 struct StreamInfo {
   // The number of bytes that are available for consumption within this
   // stream's buffer.
-  std::size_t bytes_in_stream;
+  std::size_t bytes_in_stream{0};
 
   // The total length of this stream, in case its source is finite (e.g. a
   // file on disk). May be absent for endless streams (internet streams,
   // generated audio, etc.)
-  std::optional<std::size_t> length_bytes;
+  std::optional<std::size_t> length_bytes{};
 
   struct Encoded {
     // The codec that this stream is associated with.
@@ -42,8 +42,8 @@ struct StreamInfo {
     bool operator==(const Pcm&) const = default;
   };
 
-  typedef std::variant<Encoded, Pcm> Format;
-  Format format;
+  typedef std::variant<std::monostate, Encoded, Pcm> Format;
+  Format format{};
 
   bool operator==(const StreamInfo&) const = default;
 };
@@ -91,8 +91,11 @@ class OutputStream {
   void add(std::size_t bytes) const { raw_->info->bytes_in_stream += bytes; }
 
   bool prepare(const StreamInfo::Format& new_format) {
-    if (new_format == raw_->info->format) {
+    if (std::holds_alternative<std::monostate>(raw_->info->format)) {
       raw_->info->format = new_format;
+      raw_->info->bytes_in_stream = 0;
+    }
+    if (new_format == raw_->info->format) {
       return true;
     }
     if (raw_->is_incomplete) {

src/audio/pipeline.cpp

@@ -4,7 +4,10 @@
 
 namespace audio {
 
-Pipeline::Pipeline(IAudioElement* output) : root_(output), subtrees_() {}
+Pipeline::Pipeline(IAudioElement* output) : root_(output), subtrees_() {
+  assert(output != nullptr);
+}
+
 Pipeline::~Pipeline() {}
 
 auto Pipeline::AddInput(IAudioElement* input) -> Pipeline* {

src/drivers/dac.cpp

@@ -13,6 +13,7 @@
 #include "esp_log.h"
 #include "freertos/portmacro.h"
 #include "freertos/projdefs.h"
+#include "hal/gpio_types.h"
 #include "hal/i2c_types.h"
 
 #include "gpio_expander.hpp"
@@ -50,9 +51,8 @@ auto AudioDac::create(GpioExpander* expander)
   i2s_std_config_t i2s_config = {
       .clk_cfg = dac->clock_config_,
       .slot_cfg = dac->slot_config_,
-      .gpio_cfg =
-          {// TODO: investigate running in three wire mode for less noise
-           .mclk = GPIO_NUM_0,
+      .gpio_cfg = {.mclk = GPIO_NUM_0,
+                   //.mclk = I2S_GPIO_UNUSED,
                    .bclk = GPIO_NUM_26,
                    .ws = GPIO_NUM_27,
                    .dout = GPIO_NUM_5,
@@ -65,6 +65,9 @@ auto AudioDac::create(GpioExpander* expander)
                        }},
   };
 
+  // gpio_set_direction(GPIO_NUM_0, GPIO_MODE_OUTPUT);
+  // gpio_set_level(GPIO_NUM_0, 0);
+
   if (esp_err_t err =
           i2s_channel_init_std_mode(i2s_handle, &i2s_config) != ESP_OK) {
     ESP_LOGE(kTag, "failed to initialise i2s channel %x", err);
@@ -81,20 +84,29 @@ auto AudioDac::create(GpioExpander* expander)
 
   // The DAC should be booted but in power down mode, but it might not be if we
   // didn't shut down cleanly. Reset it to ensure it is in a consistent state.
-  dac->WriteRegister(Register::POWER_MODE, 0b10001);
   dac->WriteRegister(Register::POWER_MODE, 1 << 4);
   dac->WriteRegister(Register::RESET, 0b10001);
 
+  // Use BCK for the internal PLL.
+  // dac->WriteRegister(Register::PLL_CLOCK_SOURCE, 1 << 4);
+
+  // dac->WriteRegister(Register::PLL_ENABLE, 0);
+  dac->WriteRegister(Register::INTERPOLATION, 1 << 4);
+
+  dac->Reconfigure(BPS_16, SAMPLE_RATE_44_1);
+  dac->WriteRegister(Register::POWER_MODE, 0);
+
   // Now configure the DAC for standard auto-clock SCK mode.
-  dac->WriteRegister(Register::DAC_CLOCK_SOURCE, 0b11 << 5);
+  // dac->WriteRegister(Register::DAC_CLOCK_SOURCE, 0b11 << 5);
 
   // Enable auto clocking, and do your best to carry on despite errors.
   // dac->WriteRegister(Register::CLOCK_ERRORS, 0b1111101);
 
-  i2s_channel_enable(dac->i2s_handle_);
+  // i2s_channel_enable(dac->i2s_handle_);
 
-  dac->WaitForPowerState(
-      [](bool booted, PowerState state) { return state == STANDBY; });
+  dac->WaitForPowerState([](bool booted, PowerState state) {
+    return state == RUN || state == STANDBY;
+  });
 
   return dac;
 }
@@ -102,6 +114,7 @@ auto AudioDac::create(GpioExpander* expander)
 AudioDac::AudioDac(GpioExpander* gpio, i2s_chan_handle_t i2s_handle)
     : gpio_(gpio),
       i2s_handle_(i2s_handle),
+      i2s_active_(false),
       clock_config_(I2S_STD_CLK_DEFAULT_CONFIG(44100)),
       slot_config_(I2S_STD_MSB_SLOT_DEFAULT_CONFIG(I2S_DATA_BIT_WIDTH_16BIT,
                                                    I2S_SLOT_MODE_STEREO)) {
@@ -163,9 +176,10 @@ bool AudioDac::WaitForPowerState(
 }
 
 auto AudioDac::Reconfigure(BitsPerSample bps, SampleRate rate) -> void {
-  // Disable the current output, if it isn't already stopped.
-  WriteRegister(Register::POWER_MODE, 1 << 4);
+  WriteRegister(Register::RESYNC_REQUEST, 1);
+  if (i2s_active_) {
     i2s_channel_disable(i2s_handle_);
+  }
 
   // I2S reconfiguration.
 
@@ -181,15 +195,21 @@ auto AudioDac::Reconfigure(BitsPerSample bps, SampleRate rate) -> void {
   ESP_ERROR_CHECK(i2s_channel_reconfig_std_clock(i2s_handle_, &clock_config_));
 
   // DAC reconfiguration.
+  if (rate == SAMPLE_RATE_44_1) {
+    WriteRegister(Register::DE_EMPHASIS, 1 << 4);
+  } else {
+    WriteRegister(Register::DE_EMPHASIS, 0);
+  }
 
   // TODO: base on BPS
-  WriteRegister(Register::I2S_FORMAT, 0);
+  WriteRegister(Register::I2S_FORMAT, 0b00);
 
   // Configuration is all done, so we can now bring the DAC and I2S stream back
   // up. I2S first, since otherwise the DAC will see that there's no clocks and
   // shut itself down.
+  WriteRegister(Register::RESYNC_REQUEST, 0);
   ESP_ERROR_CHECK(i2s_channel_enable(i2s_handle_));
-  WriteRegister(Register::POWER_MODE, 0);
+  i2s_active_ = true;
 }
 
 auto AudioDac::WriteData(const cpp::span<const std::byte>& data) -> void {

src/drivers/include/dac.hpp

@@ -83,6 +83,7 @@ class AudioDac {
  private:
   GpioExpander* gpio_;
   i2s_chan_handle_t i2s_handle_;
+  bool i2s_active_;
 
   i2s_std_clk_config_t clock_config_;
   i2s_std_slot_config_t slot_config_;
@@ -97,9 +98,13 @@ class AudioDac {
     PAGE_SELECT = 0,
     RESET = 1,
     POWER_MODE = 2,
+    PLL_ENABLE = 4,
     DE_EMPHASIS = 7,
+    PLL_CLOCK_SOURCE = 13,
     DAC_CLOCK_SOURCE = 14,
+    RESYNC_REQUEST = 19,
     CLOCK_ERRORS = 37,
+    INTERPOLATION = 34,
     I2S_FORMAT = 40,
     DIGITAL_VOLUME_L = 61,
     DIGITAL_VOLUME_R = 62,

src/main/main.cpp

@@ -41,7 +41,7 @@
 static const char* TAG = "MAIN";
 
 void IRAM_ATTR tick_hook(void) {
-  lv_tick_inc(1);
+  // lv_tick_inc(1);
 }
 
 static const size_t kLvglStackSize = 8 * 1024;

src/memory/include/himem.hpp

@@ -57,21 +57,26 @@ class MappableRegion {
   }
 
   auto Get() -> cpp::span<std::byte> {
-    if (bytes_ != nullptr) {
+    if (bytes_ == nullptr) {
       return {};
     }
     return {bytes_, size};
   }
 
   auto Map(const HimemAlloc<size>& alloc) -> cpp::span<std::byte> {
-    if (bytes_ != nullptr) {
-      ESP_ERROR_CHECK(esp_himem_unmap(range_handle, bytes_, size));
-    }
+    assert(bytes_ == nullptr);
     ESP_ERROR_CHECK(esp_himem_map(alloc.handle, range_handle, 0, 0, size, 0,
                                   reinterpret_cast<void**>(&bytes_)));
     return Get();
   }
 
+  auto Unmap() -> void {
+    if (bytes_ != nullptr) {
+      ESP_ERROR_CHECK(esp_himem_unmap(range_handle, bytes_, size));
+      bytes_ = nullptr;
+    }
+  }
+
   // Not copyable or movable.
   MappableRegion(const MappableRegion&) = delete;
   MappableRegion& operator=(const MappableRegion&) = delete;