linux-drivers/
drivers/dma/stm32

STMicroelectronics STM32 on-chip DMA controllers

On-chip Direct Memory Access engines built into ST's STM32 microcontrollers and STM32MP application processors, used to move data between memory and peripherals without tying up the CPU. Covers four hardware blocks (DMA, DMAMUX, MDMA, and the newer DMA3 in the STM32MP2 family) found in industrial and embedded Linux systems.

keep conf=0.92 deploy=medium replacement=none subsystem=dma category=bus-other
92%

recommendation

It should stay in the kernel because the hardware is current and actively shipping: ST launched the STM32MP25 line through DigiKey in late 2024, and upstream activity is healthy, with the DMA3 driver introduced in 2024 and both DMA3 and MDMA still receiving fixes through November and December 2025. Because these are SoC-specific engines, no other driver could replace them, and there is no sign of deprecation discussion.

repository signals

6 files
6,053 source lines
25 commits, 5y
+6,204 / −99 lines added / removed, 5y
7 authors, 5y
monthly commits · 2021-04-21 → 2026-04-21 · 25 total · active in 7/61 months
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sources

  1. spinics.net

    STM32 DMA3 support was introduced upstream in 2024 as an active 12-patch series touching drivers/dma/stm32, indicating new enablement rather than retirement.

  2. spinics.net

    The STM32 DMA3 driver was still receiving functional fixes/improvements in November 2025, showing ongoing upstream maintenance.

  3. spinics.net

    The STM32 MDMA driver received a December 2025 warning fix that was accepted upstream, again showing live maintenance.

  4. cateee.net

    LKDDb lists CONFIG_STM32_DMA3 for Linux 6.11 through 6.19 and 7.0-rc+HEAD, tied to compatible string st,stm32mp25-dma3.

  5. st.com

    ST markets the STM32MP2 family, including STM32MP25, as a current industrial-grade MPU line and the page exposes current 'Buy now' product selectors.

  6. globenewswire.com

    DigiKey announced STM32MP25 availability in December 2024, supporting that hardware using this driver family was entering new-channel sales around 2025.

codex reasoning notes (technical)

Local inspection via exec_command showed four real platform DMA drivers in this directory (stm32-dma, stm32-dmamux, stm32-mdma, stm32-dma3) with Kconfig entries for on-chip STM32 DMA blocks; local git log via exec_command showed substantive touches through 2025-12-23. Mailing-list evidence was obtained via web search because lore MCP/lei were unavailable here: spinics results show the directory was created in 2024 for active consolidation, DMA3 was introduced there, and STM32 DMA3/MDMA still received fixes in late 2025. Separate web search found no removal/deprecation discussion terms for this driver family. Deployment is medium, not high: these are on-SoC DMA engines for STM32 MCUs/MPUs used in embedded/industrial systems, including current STM32MP2 parts, but not broad commodity PC hardware. No natural replacement driver exists because these are SoC-specific DMA controller drivers.