7561d2c5c2
Move per-target I2S regdma retention descriptors out of esp_hal_i2s and into esp_driver_i2s so the driver owns its backup scope and restore sequence.
ESP Hardware Abstraction Layer for I2S Peripheral(s)
Note
This component is currently in beta. Its API, behavior, and compatibility may change at any time and without notice; backward compatibility is not guaranteed. Use caution when integrating into production systems.
Overview
The esp_hal_i2s component provides a Hardware Abstraction Layer for Inter-IC Sound (I2S) controllers across all ESP-IDF supported targets. I2S is a serial bus interface standard used for connecting digital audio devices, enabling high-quality audio data transmission between integrated circuits.
Architecture
The I2S HAL is structured in two main sub-layers:
-
HAL Layer (Upper): Defines the operational steps and data structures required to control I2S peripherals (e.g., initialization, clock configuration, STD/TDM/PDM slot configuration, channel enable/disable).
-
Low-Level Layer (Bottom): Serves as a translation layer between the HAL and the register files defined in the
soccomponent, handling target-specific register configurations.
Supported I2S Controllers
This HAL supports two I2S controller types depending on the ESP chip:
- Standard I2S: Traditional I2S interface supporting master/slave modes. And the different hardware versions are supported regarding different chips.
- Low-Power I2S (LP I2S): Power-efficient I2S controller for low-power applications (on supported chips)
Features
- Multiple Audio Formats:
- Standard I2S (STD) mode
- Pulse Density Modulation (PDM) mode
- Time Division Multiplexing (TDM) mode
- Master/Slave Mode Support: Configurable as master or slave device
- Bidirectional Communication: Independent TX and RX channel configuration
- Clock Configuration: Precise master clock (MCLK) and bit clock (BCLK) division
- Slot Configuration: Mono/stereo mode, slot selection, bit width configuration
- PDM/PCM Converter Features: PCM-to-PDM and PDM-to-PCM conversion, high-pass filtering (on supported chips)
- TDM Features: Multi-slot TDM support with configurable slot masks
- Signal Connection Management: GPIO signal mapping and interrupt configuration
Usage
The HAL functions primarily serve ESP-IDF peripheral drivers such as esp_driver_i2s.
Advanced developers can use these interfaces directly when implementing custom drivers, with the understanding that API stability is not guaranteed.
Dependencies
soc: Provides chip-specific register definitionshal: Core hardware abstraction utilities and macros