[PATCH 0/4] mfd: Add support for the MCU in the UGREEN DH2300 NAS

[Alexey Charkov]

UGREEN DH2300 is a 2-bay SATA NAS based on the Rockchip RK3576 SoC. It
includes an embedded controller connected over I2C which won't let the
drives power up without its register being poked first, which precludes
the use of the device for its main purpose.

There is no public documentation or source code available, but apparently
the MCU is also responsible for a hardware watchdog function and some type
of wake functionality, so this series implements an MFD-regulator
separation right away to allow for adding these functions properly later
on.

For now though a single-bit write to the MCU seems to be sufficient to get
the drives to work with only a board DTS addition [1] - to be submitted
separately.

[1] https://github.com/flipperdevices/flipper-linux-kernel/blob/2c1c5ee609f6ed4c77e9e5428df91e98b3f50cce/arch/arm64/boot/dts/rockchip/rk3576-nasync-dh2300.dts

Signed-off-by: Alexey Charkov <alchark at flipper.net>
---
Alexey Charkov (4):
      dt-bindings: vendor-prefixes: Add Ugreen Group Limited
      dt-bindings: mfd: Add UGREEN NASync DH2300 MCU
      mfd: Add support for UGREEN NASync DH2300 MCU
      regulator: Add support for UGREEN NASync DH2300 MCU SATA power gate

 .../devicetree/bindings/mfd/ugreen,dh2300-mcu.yaml | 62 +++++++++++++++++
 .../devicetree/bindings/vendor-prefixes.yaml       |  2 +
 MAINTAINERS                                        |  7 ++
 drivers/mfd/Kconfig                                | 16 +++++
 drivers/mfd/Makefile                               |  1 +
 drivers/mfd/ugreen-dh2300-mcu.c                    | 60 ++++++++++++++++
 drivers/regulator/Kconfig                          | 12 ++++
 drivers/regulator/Makefile                         |  1 +
 drivers/regulator/ugreen-dh2300-mcu-regulator.c    | 80 ++++++++++++++++++++++
 9 files changed, 241 insertions(+)
---
base-commit: ec039126b7fac4e3af35ebccaa7c6f9b6875ba81
change-id: 20260612-dh2300-mcu-5354d1f5f11a

Best regards,
--  
Alexey Charkov <alchark at flipper.net>