Re: [PATCH v8 2/2] mfd: ac200: Add X-Powers AC200 support

[Lee Jones <lee@kernel.org>]

On Wed, 02 Sep 2026, sashiko-bot@kernel.org wrote:

> Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
> - [High] Unconditional global chip reset in shutdown/remove breaks RTC wake, Wake-on-LAN, and live PHY state.

Is that true?  Needs a response from you.

> --
> 
> commit d8592c963caa9b21487926208ea5815e059be1be
> Author: James Hilliard <james.hilliard1@gmail.com>
> 
> mfd: ac200: Add X-Powers AC200 support
>     
> This commit adds support for the X-Powers AC200 mixed-signal companion IC.
> It enables the shared input clock, initializes the paged regmap, and asserts
> a chip reset during probe, driver removal, and system shutdown.
> 
> > diff --git a/drivers/mfd/ac200.c b/drivers/mfd/ac200.c
> > new file mode 100644
> > index 0000000000000..8445a460ef6c2
> > --- /dev/null
> > +++ b/drivers/mfd/ac200.c
> 
> [ ... ]
> 
> > +static void ac200_disable(struct regmap *regmap)
> > +{
> > +	regmap_write(regmap, AC200_SYS_CONTROL_REG, 0);
> > +}
> 
> [Severity: High]
> Does asserting a global chip reset here wipe the hardware state of all
> co-packaged functions, including the RTC and Fast Ethernet PHY?
> 
> Since ac200_disable() is unconditionally called by ac200_shutdown() and
> ac200_remove(), could this kill the PHY and clear the RTC during system
> shutdown, breaking Wake-on-LAN and Wake-on-RTC from power-off states?
> 
> Furthermore, because the PHY is enumerated separately on the MDIO bus and
> only references this MFD via a phandle, will unbinding the AC200 driver at
> runtime (via ac200_remove) forcefully reset the PHY hardware out from under
> the active MDIO PHY driver and lead to unpredictable network failures?
> 
> [ ... ]
> 
> -- 
> Sashiko AI review · https://sashiko.dev/#/patchset/20260902-submit-ac200-mfd-v8-0-2aa06720b8ac@gmail.com?part=2

-- 
Lee Jones