April 2025: AmbiqMicro/ambiqzephyr contributed a targeted device-tree pinctrl fix for the stm32h7s78_dk board to support 16-bit SPI memory (hexadeca SPI). The patch updates the SoC pinctrl dtsi and adds missing pinctrl nodes per the datasheet, ensuring correct configuration for 16-bit SPI transfers and reducing memory access issues during board bring-up. The work improves stability and enables reliable use of 16-bit SPI memories on this board, setting a foundation for future SPI memory performance improvements.

February 2025 monthly summary: Delivered two key audio capabilities in telink-semi/zephyr, strengthening hardware support and enabling immediate audio functionality on two platforms. Implemented CS43L22 DAC driver with full headphone left/right channel support, and activated audio output on the stm32f4_disco board with I2S codec integration. Addressed a missing headphone channel bug to ensure correct stereo playback and set up board overlays for streamlined codec demos. Business impact: expands hardware compatibility, accelerates audio feature prototyping, and improves reliability of audio paths in consumer-grade devices. Technologies demonstrated include I2S, PLLI2S, DMA, I2C, Zephyr codec shells, and STM32 board overlays.

December 2024: Delivered USB OTGFS support on STM32H7S78-DK within telink-semi/zephyr, enabling USB device functionality by configuring device-tree nodes and enabling the USB device driver; documentation updated to reflect the new hardware capability. This feature broadens hardware support and enables USB device mode for development and product scenarios on the STM32H7S78-DK.