Audio System + Drivers (#562)

Drivers/es7210-module/CMakeLists.txt

@@ -0,0 +1,11 @@
+cmake_minimum_required(VERSION 3.20)
+
+include("${CMAKE_CURRENT_LIST_DIR}/../../Buildscripts/module.cmake")
+
+file(GLOB_RECURSE SOURCE_FILES "source/*.c*")
+
+tactility_add_module(es7210-module
+    SRCS ${SOURCE_FILES}
+    INCLUDE_DIRS include/
+    REQUIRES TactilityKernel audio-codec-module esp_codec_dev
+)

Drivers/es7210-module/LICENSE-Apache-2.0.md

@@ -0,0 +1,195 @@
+Apache License
+==============
+
+_Version 2.0, January 2004_  
+_&lt;<http://www.apache.org/licenses/>&gt;_
+
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+

Drivers/es7210-module/README.md

@@ -0,0 +1,18 @@
+# ES7210 microphone ADC
+
+A driver for the `ES7210` 4-channel microphone ADC by Everest Semiconductor,
+wired as an input-only `AUDIO_CODEC_TYPE` device. The I2C bus is the device's
+parent; the I2S controller carrying the (4-slot TDM) audio data is referenced by
+name.
+
+Always configures the hardware for the full 4-slot TDM frame regardless of how
+many mics are actually wired (`mic-mask`), then demuxes down to just the active
+mic slots in software -- `es7210_set_fs()` silently halves the configured bit
+depth when asked for 2 or fewer TDM channels, which corrupts audio if the mic
+count is passed straight through.
+
+Wraps Espressif's `esp_codec_dev` ES7210 implementation.
+
+See https://www.everest-semi.com/pdf/ES7210%20PB.pdf
+
+License: [Apache v2.0](LICENSE-Apache-2.0.md)

Drivers/es7210-module/bindings/everest,es7210.yaml

@@ -0,0 +1,20 @@
+description: Everest Semiconductor ES7210 4-channel microphone ADC
+
+include: ["i2c-device.yaml"]
+
+compatible: "everest,es7210"
+
+properties:
+  i2s:
+    type: phandle
+    required: true
+    description: "I2S controller device that carries audio data"
+  mic-mask:
+    type: int
+    required: false
+    default: 15
+    description: "Bitmask of microphones to enable (bit0=MIC1 .. bit3=MIC4); defaults to all four"
+  input-gain-percent:
+    type: int
+    default: 100
+    description: "Extra digital gain multiplier applied by audio_stream on top of the ES7210's own 30dB hardware ADC gain, as an integer percentage (100 = 1.0x / no extra boost). devicetree has no float type, hence x100."

Drivers/es7210-module/devicetree.yaml

@@ -0,0 +1,3 @@
+dependencies:
+  - TactilityKernel
+bindings: bindings

Drivers/es7210-module/include/bindings/es7210.h

@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: Apache-2.0
+#pragma once
+
+#include <tactility/bindings/bindings.h>
+#include <drivers/es7210.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+DEFINE_DEVICETREE(es7210, struct Es7210Config)
+
+#ifdef __cplusplus
+}
+#endif

Drivers/es7210-module/include/drivers/es7210.h

@@ -0,0 +1,42 @@
+// SPDX-License-Identifier: Apache-2.0
+#pragma once
+
+#include <stdint.h>
+#include <stdbool.h>
+#include <tactility/error.h>
+#include <tactility/drivers/audio_codec.h>
+
+struct Device;
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * @brief ES7210 codec device configuration.
+ *
+ * The ES7210 is an input-only (microphone ADC) codec. The I2C bus is the
+ * device's parent (per i2c-device.yaml), while the I2S controller carrying
+ * the (typically 4-slot TDM) audio data is referenced via a devicetree phandle.
+ */
+struct Es7210Config {
+    /** I2C address on the bus (typically 0x40) */
+    uint8_t address;
+    /** I2S controller device that carries audio data */
+    struct Device* i2s_device;
+    /** Bitmask of microphones to enable, e.g. ES7210_SEL_MIC1 | ES7210_SEL_MIC2 | ... */
+    uint8_t mic_selected_mask;
+    /**
+     * Extra fixed digital gain multiplier applied by audio_stream on top of the ES7210's
+     * own hardware ADC gain (already at a hard-coded 30dB default out of a 0..37.5dB
+     * range), as an integer percentage (100 = 1.0x / no extra boost). Small MEMS mic
+     * capsules can still sound quiet even near max hardware gain; this is for boards where
+     * 30dB hardware gain alone isn't enough. devicetree has no float property type, hence
+     * the x100 integer encoding.
+     */
+    uint16_t input_gain_percent;
+};
+
+#ifdef __cplusplus
+}
+#endif

Drivers/es7210-module/include/es7210_module.h

@@ -0,0 +1,14 @@
+// SPDX-License-Identifier: Apache-2.0
+#pragma once
+
+#include <tactility/module.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+extern struct Module es7210_module;
+
+#ifdef __cplusplus
+}
+#endif

Drivers/es7210-module/source/es7210.cpp

@@ -0,0 +1,435 @@
+// SPDX-License-Identifier: Apache-2.0
+#include <drivers/es7210.h>
+
+#include <tactility/device.h>
+#include <tactility/drivers/audio_codec.h>
+#include <tactility/drivers/audio_codec_adapters.h>
+#include <tactility/drivers/i2c_controller.h>
+#include <tactility/drivers/i2s_controller.h>
+#include <tactility/log.h>
+
+#include <es7210_adc.h>
+#include <esp_codec_dev.h>
+#include <esp_codec_dev_defaults.h>
+
+#include <cstring>
+#include <vector>
+
+#define TAG "ES7210"
+
+namespace {
+
+constexpr uint32_t NATIVE_SAMPLE_RATE = 16000;
+constexpr float MAX_INPUT_GAIN_DB = 37.5f; // ES7210 mic gain range is roughly 0..37.5 dB
+
+struct Es7210Data {
+    const audio_codec_ctrl_if_t* ctrl_if = nullptr;
+    const audio_codec_data_if_t* data_if = nullptr;
+    const audio_codec_if_t* codec_if = nullptr;
+    esp_codec_dev_handle_t codec_device = nullptr;
+    bool is_open = false;
+    uint8_t mic_count = 4;
+    uint8_t mic_mask = 0x0F;
+    uint8_t tdm_slot_count = 4;
+    uint8_t open_bits_per_sample = 16;
+    uint32_t open_sample_rate = 0;
+    float input_gain = 1.0f;
+    std::vector<uint8_t> raw_buffer;
+};
+
+#define GET_CONFIG(device) (static_cast<const Es7210Config*>((device)->config))
+#define GET_DATA(device) (static_cast<Es7210Data*>(device_get_driver_data(device)))
+
+// region AudioCodecApi
+
+error_t open(Device* device, const struct AudioCodecStreamConfig* config) {
+    auto* data = GET_DATA(device);
+    if (data->codec_device == nullptr) {
+        return ERROR_RESOURCE;
+    }
+
+    if (config->direction == AUDIO_CODEC_DIR_OUTPUT || config->direction == AUDIO_CODEC_DIR_BOTH) {
+        LOG_E(TAG, "ES7210 is input-only");
+        return ERROR_NOT_SUPPORTED;
+    }
+
+    if (data->is_open) {
+        bool same_config = config->bits_per_sample == data->open_bits_per_sample
+            && config->sample_rate == data->open_sample_rate;
+        return same_config ? ERROR_NONE : ERROR_RESOURCE;
+    }
+
+    // Open with tdm_slot_count channels, not the (possibly smaller) active mic count.
+    // tdm_slot_count is set in start_device() to match whichever framing the vendor
+    // driver will actually use: the full 4-slot TDM frame when TDM mode engages
+    // (mic_count >= 3), or exactly mic_count when it doesn't (plain N-channel I2S --
+    // see start_device()'s tdm_slot_count comment). Opening with the wrong channel
+    // count here mismatches the I2S receive layout the codec actually produces,
+    // corrupting every channel past the first. When TDM *is* engaged, using the full
+    // slot count (rather than just the active mic count) also sidesteps a separate
+    // vendor quirk: es7210_set_fs() silently halves the configured bit depth when asked
+    // for <= 2 channels in TDM mode (channel_mask == 0). We demux down to the active
+    // mic slots ourselves in read().
+    uint8_t hw_channels = data->tdm_slot_count;
+
+    esp_codec_dev_sample_info_t sample_info = {
+        .bits_per_sample = config->bits_per_sample,
+        .channel = hw_channels,
+        .channel_mask = 0,
+        .sample_rate = config->sample_rate,
+        .mclk_multiple = 0,
+    };
+
+    if (esp_codec_dev_open(data->codec_device, &sample_info) != ESP_CODEC_DEV_OK) {
+        LOG_E(TAG, "Failed to open codec device");
+        return ERROR_RESOURCE;
+    }
+
+    data->open_bits_per_sample = config->bits_per_sample;
+    data->open_sample_rate = config->sample_rate;
+    data->is_open = true;
+    return ERROR_NONE;
+}
+
+error_t close(Device* device) {
+    auto* data = GET_DATA(device);
+    if (data->codec_device == nullptr) {
+        return ERROR_RESOURCE;
+    }
+
+    if (data->is_open) {
+        esp_codec_dev_close(data->codec_device);
+        data->is_open = false;
+    }
+
+    return ERROR_NONE;
+}
+
+error_t read(Device* device, void* buffer, size_t size, size_t* bytes_read, TickType_t timeout) {
+    (void) timeout;
+    auto* data = GET_DATA(device);
+    if (!data->is_open) {
+        return ERROR_RESOURCE;
+    }
+
+    // The hardware always runs at tdm_slot_count channels (see open() for why); demux down
+    // to just the active mic slots here so callers see exactly mic_count channels of real
+    // signal -- never diluted by silent/AEC-reference TDM slots.
+    if (data->mic_count == data->tdm_slot_count) {
+        int result = esp_codec_dev_read(data->codec_device, buffer, (int) size);
+        if (result < 0) {
+            return ERROR_RESOURCE;
+        }
+        *bytes_read = (size_t) result;
+        return ERROR_NONE;
+    }
+
+    uint8_t bytes_per_sample = (uint8_t) (data->open_bits_per_sample / 8);
+    size_t out_frame_bytes = (size_t) data->mic_count * bytes_per_sample;
+    size_t requested_frames = (out_frame_bytes != 0) ? (size / out_frame_bytes) : 0;
+    if (requested_frames == 0) {
+        *bytes_read = 0;
+        return ERROR_NONE;
+    }
+
+    size_t raw_frame_bytes = (size_t) data->tdm_slot_count * bytes_per_sample;
+    size_t raw_bytes_needed = requested_frames * raw_frame_bytes;
+    if (data->raw_buffer.size() < raw_bytes_needed) {
+        data->raw_buffer.resize(raw_bytes_needed);
+    }
+
+    int result = esp_codec_dev_read(data->codec_device, data->raw_buffer.data(), (int) raw_bytes_needed);
+    if (result < 0) {
+        return ERROR_RESOURCE;
+    }
+
+    size_t raw_bytes_read = (size_t) result;
+    size_t frames_read = raw_bytes_read / raw_frame_bytes;
+
+    // Demux: pick the bytes_per_sample-wide slot for each set bit in mic_mask, in ascending
+    // slot order, e.g. mic_mask = MIC1|MIC3 -> slots 0 and 2.
+    uint8_t slot_indices[8];
+    uint8_t slot_count = 0;
+    for (uint8_t slot = 0; slot < data->tdm_slot_count && slot_count < sizeof(slot_indices); slot++) {
+        if ((data->mic_mask & (uint8_t) (1u << slot)) != 0) {
+            slot_indices[slot_count++] = slot;
+        }
+    }
+
+    auto* out = static_cast<uint8_t*>(buffer);
+    const uint8_t* raw = data->raw_buffer.data();
+    for (size_t frame = 0; frame < frames_read; frame++) {
+        const uint8_t* raw_frame = raw + frame * raw_frame_bytes;
+        uint8_t* out_frame = out + frame * out_frame_bytes;
+        for (uint8_t ch = 0; ch < slot_count && ch < data->mic_count; ch++) {
+            std::memcpy(out_frame + (size_t) ch * bytes_per_sample, raw_frame + (size_t) slot_indices[ch] * bytes_per_sample, bytes_per_sample);
+        }
+    }
+
+    *bytes_read = frames_read * out_frame_bytes;
+    return ERROR_NONE;
+}
+
+error_t write(Device* device, const void* buffer, size_t size, size_t* bytes_written, TickType_t timeout) {
+    (void) device;
+    (void) buffer;
+    (void) size;
+    (void) bytes_written;
+    (void) timeout;
+    return ERROR_NOT_SUPPORTED;
+}
+
+error_t set_volume(Device* device, AudioCodecDirection direction, float volume_percent) {
+    auto* data = GET_DATA(device);
+    if (data->codec_device == nullptr || direction != AUDIO_CODEC_DIR_INPUT) {
+        return ERROR_NOT_SUPPORTED;
+    }
+
+    // Map 0..100% linearly onto the gain range.
+    float db = (volume_percent / 100.0f) * MAX_INPUT_GAIN_DB;
+    return (esp_codec_dev_set_in_gain(data->codec_device, db) == ESP_CODEC_DEV_OK) ? ERROR_NONE : ERROR_RESOURCE;
+}
+
+error_t get_volume(Device* device, AudioCodecDirection direction, float* volume_percent) {
+    auto* data = GET_DATA(device);
+    if (data->codec_device == nullptr || direction != AUDIO_CODEC_DIR_INPUT) {
+        return ERROR_NOT_SUPPORTED;
+    }
+
+    float db = 0.0f;
+    if (esp_codec_dev_get_in_gain(data->codec_device, &db) != ESP_CODEC_DEV_OK) {
+        return ERROR_RESOURCE;
+    }
+    *volume_percent = (db / MAX_INPUT_GAIN_DB) * 100.0f;
+    return ERROR_NONE;
+}
+
+error_t set_mute(Device* device, AudioCodecDirection direction, bool muted) {
+    auto* data = GET_DATA(device);
+    if (data->codec_device == nullptr || direction != AUDIO_CODEC_DIR_INPUT) {
+        return ERROR_NOT_SUPPORTED;
+    }
+
+    return (esp_codec_dev_set_in_mute(data->codec_device, muted) == ESP_CODEC_DEV_OK) ? ERROR_NONE : ERROR_RESOURCE;
+}
+
+error_t get_mute(Device* device, AudioCodecDirection direction, bool* muted) {
+    auto* data = GET_DATA(device);
+    if (data->codec_device == nullptr || direction != AUDIO_CODEC_DIR_INPUT) {
+        return ERROR_NOT_SUPPORTED;
+    }
+
+    return (esp_codec_dev_get_in_mute(data->codec_device, muted) == ESP_CODEC_DEV_OK) ? ERROR_NONE : ERROR_RESOURCE;
+}
+
+error_t get_native_channels(Device* device, AudioCodecDirection direction, uint8_t* channels) {
+    auto* data = GET_DATA(device);
+    if (direction != AUDIO_CODEC_DIR_INPUT) {
+        return ERROR_NOT_SUPPORTED;
+    }
+    *channels = data->mic_count;
+    return ERROR_NONE;
+}
+
+error_t get_native_sample_rate(Device* device, AudioCodecDirection direction, uint32_t* rate_hz) {
+    (void) device;
+    if (direction != AUDIO_CODEC_DIR_INPUT) {
+        return ERROR_NOT_SUPPORTED;
+    }
+    *rate_hz = NATIVE_SAMPLE_RATE;
+    return ERROR_NONE;
+}
+
+error_t get_capabilities(Device* device, AudioCodecDirection* supported_directions) {
+    (void) device;
+    *supported_directions = AUDIO_CODEC_DIR_INPUT;
+    return ERROR_NONE;
+}
+
+error_t get_input_gain_multiplier(Device* device, float* gain) {
+    auto* data = GET_DATA(device);
+    *gain = data->input_gain;
+    return ERROR_NONE;
+}
+
+static const struct AudioCodecApi API = {
+    .open = open,
+    .close = close,
+    .read = read,
+    .write = write,
+    .set_volume = set_volume,
+    .get_volume = get_volume,
+    .set_mute = set_mute,
+    .get_mute = get_mute,
+    .get_native_sample_rate = get_native_sample_rate,
+    .get_native_channels = get_native_channels,
+    .get_capabilities = get_capabilities,
+    .get_input_gain_multiplier = get_input_gain_multiplier,
+};
+
+// endregion
+
+// region Driver lifecycle
+
+error_t start_device(Device* device) {
+    const auto* config = GET_CONFIG(device);
+
+    // devicetree's int property type has no min/max constraint support, so a bogus
+    // negative literal would otherwise silently wrap to 65535 when narrowed to uint16_t.
+    // Bound it here instead -- 2000 (20x) is already an extreme upper bound for
+    // compensating a quiet mic capsule on top of the ES7210's own hardware gain.
+    if (config->input_gain_percent > 2000) {
+        LOG_E(TAG, "Invalid input_gain_percent %u (must be 0..2000)", config->input_gain_percent);
+        return ERROR_RESOURCE;
+    }
+
+    // Same rationale as input_gain_percent: devicetree ints aren't bit-constrained, so
+    // reject any bit outside the four supported mic slots before it inflates mic_count
+    // beyond the fixed 4-slot TDM frame that read() demuxes against.
+    constexpr uint8_t supported_mic_mask = (uint8_t) (ES7210_SEL_MIC1 | ES7210_SEL_MIC2 | ES7210_SEL_MIC3 | ES7210_SEL_MIC4);
+    if ((config->mic_selected_mask & ~supported_mic_mask) != 0) {
+        LOG_E(TAG, "Invalid mic_selected_mask 0x%02X (must be subset of 0x%02X)", config->mic_selected_mask, supported_mic_mask);
+        return ERROR_RESOURCE;
+    }
+
+    auto* i2c_controller = device_get_parent(device);
+    if (i2c_controller == nullptr || device_get_type(i2c_controller) != &I2C_CONTROLLER_TYPE) {
+        LOG_E(TAG, "Parent is not an I2C controller");
+        return ERROR_RESOURCE;
+    }
+
+    auto* i2s_controller = config->i2s_device;
+    if (i2s_controller == nullptr || device_get_type(i2s_controller) != &I2S_CONTROLLER_TYPE) {
+        LOG_E(TAG, "I2S controller device is not valid");
+        return ERROR_RESOURCE;
+    }
+
+    auto* data = new Es7210Data();
+
+    uint8_t mic_mask = (config->mic_selected_mask != 0)
+        ? config->mic_selected_mask
+        : (uint8_t) (ES7210_SEL_MIC1 | ES7210_SEL_MIC2 | ES7210_SEL_MIC3 | ES7210_SEL_MIC4);
+    data->mic_mask = mic_mask;
+    data->mic_count = (uint8_t) __builtin_popcount(mic_mask);
+    // Mirrors the vendor driver's own TDM threshold (es7210_is_tdm_mode(): TDM only
+    // engages when mic_num >= 3) -- below that it runs a plain N-channel I2S frame, not
+    // a fixed 4-slot TDM frame. Forcing a 4-channel open (see open()'s hw_channels
+    // comment) against a non-TDM 2-mic config mismatches the I2S receive layout the
+    // codec is actually producing, corrupting every channel past the first.
+    data->tdm_slot_count = (data->mic_count >= 3) ? 4 : data->mic_count;
+    data->input_gain = (float) config->input_gain_percent / 100.0f;
+
+    data->ctrl_if = audio_codec_adapter_new_i2c_ctrl(i2c_controller, config->address);
+    data->data_if = audio_codec_adapter_new_i2s_data(i2s_controller);
+    if (data->ctrl_if == nullptr || data->data_if == nullptr) {
+        LOG_E(TAG, "Failed to create adapters");
+        goto cleanup;
+    }
+
+    if (data->ctrl_if->open(data->ctrl_if, nullptr, 0) != ESP_CODEC_DEV_OK) {
+        LOG_E(TAG, "Failed to open control interface");
+        goto cleanup;
+    }
+
+    if (data->data_if->open(data->data_if, nullptr, 0) != ESP_CODEC_DEV_OK) {
+        LOG_E(TAG, "Failed to open data interface");
+        goto cleanup;
+    }
+
+    {
+        es7210_codec_cfg_t codec_config = {};
+        codec_config.ctrl_if = data->ctrl_if;
+        codec_config.master_mode = false;
+        codec_config.mic_selected = mic_mask;
+        codec_config.mclk_src = ES7210_MCLK_FROM_PAD;
+        codec_config.mclk_div = 0;
+
+        data->codec_if = es7210_codec_new(&codec_config);
+        if (data->codec_if == nullptr) {
+            LOG_E(TAG, "Failed to create ES7210 codec interface");
+            goto cleanup;
+        }
+    }
+
+    {
+        esp_codec_dev_cfg_t dev_config = {
+            .dev_type = ESP_CODEC_DEV_TYPE_IN,
+            .codec_if = data->codec_if,
+            .data_if = data->data_if,
+        };
+
+        data->codec_device = esp_codec_dev_new(&dev_config);
+        if (data->codec_device == nullptr) {
+            LOG_E(TAG, "Failed to create codec device");
+            goto cleanup;
+        }
+    }
+
+    device_set_driver_data(device, data);
+    return ERROR_NONE;
+
+cleanup:
+    // Mirrors stop_device's teardown order -- delete_*_if() routines close their interface
+    // first, so we don't need separate ->close() calls here.
+    if (data->codec_device != nullptr) {
+        esp_codec_dev_delete(data->codec_device);
+    }
+    if (data->codec_if != nullptr) {
+        audio_codec_delete_codec_if(data->codec_if);
+    }
+    if (data->data_if != nullptr) {
+        audio_codec_delete_data_if(data->data_if);
+    }
+    if (data->ctrl_if != nullptr) {
+        audio_codec_delete_ctrl_if(data->ctrl_if);
+    }
+    delete data;
+    return ERROR_RESOURCE;
+}
+
+error_t stop_device(Device* device) {
+    auto* data = GET_DATA(device);
+    if (data == nullptr) {
+        return ERROR_NONE;
+    }
+
+    if (data->is_open) {
+        esp_codec_dev_close(data->codec_device);
+    }
+
+    if (data->codec_device != nullptr) {
+        esp_codec_dev_delete(data->codec_device);
+    }
+    if (data->codec_if != nullptr) {
+        audio_codec_delete_codec_if(data->codec_if);
+    }
+    if (data->data_if != nullptr) {
+        audio_codec_delete_data_if(data->data_if);
+    }
+    if (data->ctrl_if != nullptr) {
+        audio_codec_delete_ctrl_if(data->ctrl_if);
+    }
+
+    device_set_driver_data(device, nullptr);
+    delete data;
+    return ERROR_NONE;
+}
+
+// endregion
+
+} // namespace
+
+extern "C" {
+
+Driver es7210_driver = {
+    .name = "es7210",
+    .compatible = (const char*[]) { "everest,es7210", nullptr },
+    .start_device = start_device,
+    .stop_device = stop_device,
+    .api = &API,
+    .device_type = &AUDIO_CODEC_TYPE,
+    .owner = nullptr,
+    .internal = nullptr,
+};
+
+}

Drivers/es7210-module/source/module.cpp

@@ -0,0 +1,30 @@
+// SPDX-License-Identifier: Apache-2.0
+#include <tactility/check.h>
+#include <tactility/driver.h>
+#include <tactility/module.h>
+
+extern "C" {
+
+extern Driver es7210_driver;
+
+static error_t start() {
+    check(driver_construct_add(&es7210_driver) == ERROR_NONE);
+    return ERROR_NONE;
+}
+
+static error_t stop() {
+    check(driver_remove_destruct(&es7210_driver) == ERROR_NONE);
+    return ERROR_NONE;
+}
+
+extern const ModuleSymbol es7210_module_symbols[];
+
+Module es7210_module = {
+    .name = "es7210",
+    .start = start,
+    .stop = stop,
+    .symbols = es7210_module_symbols,
+    .internal = nullptr
+};
+
+}

Drivers/es7210-module/source/symbols.c

@@ -0,0 +1,6 @@
+// SPDX-License-Identifier: Apache-2.0
+#include <tactility/module.h>
+
+const struct ModuleSymbol es7210_module_symbols[] = {
+    MODULE_SYMBOL_TERMINATOR
+};