V0.3.0 - Major Redesign: Header Only Implementation

Summary of Changes: v0.3.0

71 commits | 118 source files changed (+20,401 / -15,018 lines, excluding generated docs)

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1. Header-Only Library Conversion

The entire library has been converted from a compiled library (.c / .cpp source files) to a header-only C++ library. All codec implementations that were previously in .c/.cpp files under src/Driver/ have been rewritten as inline C++ classes in .h files under src/Codecs/.

Deleted (36 files): All .c/.cpp source files under src/Driver/ — ac101.c, es8388.c, wm8960.cpp, wm8994.c, etc., plus platform .cpp files (API_I2C_Arduino.cpp, API_I2C_EspressifIDF.cpp, API_SPI_Arduino.cpp, LoggerSTD.cpp, etc.).

CMakeLists.txt now declares the library as INTERFACE (no SRC_DIRS/add_library with sources), and the ESP-IDF component registration only sets INCLUDE_DIRS.

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2. Zephyr RTOS Support

The core addition of this branch — full Zephyr RTOS platform support alongside Arduino and ESP-IDF:

• GPIO abstraction: GpioPin is now gpio_dt_spec on Zephyr (device-tree based) vs int16_t on Arduino/IDF. New files: src/Platforms/GPIO_Zephyr.h, src/Platforms/GPIO_Arduino.h, src/Platforms/GPIO_EspressifIDF.h. The dispatcher src/Platforms/GPIO.h selects the right implementation via #ifdef.
• I2C/SPI: src/Platforms/API_I2C.h now contains inline implementations for all three platforms (Arduino, ESP-IDF, Zephyr) in a single header, replacing the separate .cpp files. Same pattern for SPI.
• Device info: New src/DriverDeviceInfoZephyr.h provides a Zephyr-specific DriverDeviceInfoZephyr class using Zephyr's device* handles instead of integer pin numbers.
• Board definitions: Each board header (e.g., src/AudioBoards/AudioKitEs8388v1.h) now has #if defined(IS_ZEPHYR) / #else blocks to support device-tree-based pin configuration.
• CMake: Adds __zephyr__ compile definition and links zephyr_interface when ZEPHYR_PLATFORM is set.
• Delay abstraction: New src/Platforms/API_Delay.h — delay() renamed to delayMs() for cross-platform compatibility.

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3. Major Renames and Restructuring

Old Name	New Name
src/Driver.h	src/AudioDriver.h
src/DriverConstants.h	src/Codecs/CodecConstants.h
src/DriverPins.h	src/DriverDeviceInfo.h
src/Platforms/IDriverPins.h	src/Platforms/IDriverDeviceInfo.h
DriverPins class	DriverDeviceInfo class
PinsI2S, PinsSPI, PinsI2C	InfoI2S, InfoSPI, InfoI2C (with backward aliases)
PinsFunction	InfoGPIO
src/Driver/* (codec dir)	src/Codecs/* (uppercase filenames)

Board definitions moved from inline in AudioBoard.h to individual files under src/AudioBoards/, with an aggregator src/AudioBoards/AudioBoards.h. Boards are only auto-included on non-Zephyr platforms.

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4. New Codec Drivers (14 added)

These codecs are new (not present on main in any form):

Codec	File
AW88298	src/Codecs/aw88298/AW88298.h
CS42L51	src/Codecs/cs42l51/CS42L51.h
DA7212	src/Codecs/da7212/DA7212.h
MAX98091	src/Codecs/max98091/MAX98091.h
PCM1681	src/Codecs/pcm1681/PCM1681.h
SF32LB	src/Codecs/sf32lb/SF32LB.h
SGTL5000	src/Codecs/sgtl5000/SGTL5000.h
TAS2563	src/Codecs/tas2563/TAS2563.h
TAS6422DAC	src/Codecs/tas6422dac/TAS6422DAC.h
TLV320AIC3110	src/Codecs/tlv320aic3110/TLV320AIC3110.h
TLV320DAC310x	src/Codecs/tlv320dac310x/TLV320DAC310x.h
WM8731	src/Codecs/wm8731/WM8731.h
WM8904	src/Codecs/wm8904/WM8904.h
WM8962	src/Codecs/wm8962/WM8962.h

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5. Converted Codecs (C/C++ → Header-Only C++)

All existing codecs were rewritten from C (with separate .c/.h pairs and typedef structs) to idiomatic C++ header-only classes. Codec file names are now UpperCase (e.g., es8388.c → ES8388.h). The PCBCUPID_ prefix was removed from NAU8325.

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6. Platform Abstraction Cleanup

• DriverCommon.h: Now contains all platform detection, type aliases (GpioPin, ADCPin, i2c_bus_handle_t), enum definitions (converted from typedef enum to enum/enum class), and Zephyr-specific includes. Platform constants (HIGH, LOW, INPUT, OUTPUT) are defined for non-Arduino builds.
• Macros: IS_GPIO(pin), GPIO_TO_INT(pin), GPIO_UNDEFINED are now platform-aware macros.
• etc.h: Deleted (was a grab-bag of platform compat definitions now in DriverCommon.h).

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7. Build & Config

• Version: 0.2.1 → 0.3.0
• Project name: arduino-audio-driver
• AUDIO_DRIVER_USE_NEW_API: New define in src/ConfigAudioDriver.h marking the new class names are in use.
• README: Updated to reflect multi-platform scope (Arduino + Zephyr + IDF), header-only nature, removed inline driver/board listing (moved to Wiki).

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8. Board Definitions

Board definitions are now modular per-file under src/AudioBoards/ with dual-path pin setup (IS_ZEPHYR for device-tree specs, else integer pins). New board files: Lyrat42.h, Lyrat43.h, LyratMini.h (with ADC key support), M5stackAtomEchoS3R.h. The ESP32S3AISmartSpeaker.h and STM32F411Disco.h were moved into this directory.