Re: [PATCH 3/4] mfd: Add support for UGREEN NASync DH2300 MCU

[Alexey Charkov]

On Thu, Jun 18, 2026 at 4:40 PM Lee Jones <lee@xxxxxxxxxx> wrote:
>
> On Fri, 12 Jun 2026, Alexey Charkov wrote:
>
> > Add a driver for the HC32F005 MCU used as an embedded controller on the
> > UGREEN NASync DH2300 NAS.
> >
> > This part provides the shared I2C regmap to be used by function-specific
> > sub-devices, and instantiates the SATA drive-bay power gate regulator.
> > Implemented as an MFD to allow for other functions of the MCU to be added
> > later: vendor binaries imply that it also provides a hardware watchdog
> > and somehow serves as a wake source, but so far only the SATA power gating
> > function has been confirmed in absence of documentation and sources for the
> > vendor firmware.
> >
> > Signed-off-by: Alexey Charkov <alchark@xxxxxxxxxxx>
> > ---
> >  MAINTAINERS                     |  1 +
> >  drivers/mfd/Kconfig             | 16 +++++++++++
> >  drivers/mfd/Makefile            |  1 +
> >  drivers/mfd/ugreen-dh2300-mcu.c | 60 +++++++++++++++++++++++++++++++++++++++++
> >  4 files changed, 78 insertions(+)
>
> Did you see: drivers/mfd/simple-mfd-i2c.c ?

Oh. Now I did :-D

It's exactly what I needed, thanks a lot for the pointer. Will drop
the boilerplate in v2 and instead instantiate my tiny child device
from there.

Best regards,
Alexey