Re: [PATCH v4 6/7] ARM: dts: aspeed: yosemite5: Add PDB IO expander

[Kevin Tung]

On Mon, Feb 9, 2026 at 2:27 PM Andrew Jeffery
<andrew@xxxxxxxxxxxxxxxxxxxx> wrote:
>
> On Fri, 2026-01-30 at 16:20 +0800, Kevin Tung wrote:
> > The new hardware design adds an IO expander on the PDB
> >
>
> What does "PDB" mean? Can you please expand this in the commit message?
>
> >  to support
> > fan presence detection and HSC
> >
>
> What does "HSC" mean? Can you please expand this in the commit message?
>
Hi Andrew,

Sure, I have expanded both abbreviations in the commit message as requested.

Kevin

> >  fault monitoring. So Add the PDB
> > IO expander device node to the DTS.
> >
> > The IO expander interrupt is connected to SGPIO92, which was
> > previously named ALERT_PADDLE2_SMB_N and not used by the system.
> > This pin is now repurposed and renamed to FM_IOE_ALT_N to reflect
> > its function as the PDB IO expander interrupt.
> >
> > Signed-off-by: Kevin Tung <kevin.tung.openbmc@xxxxxxxxx>
> > ---
> >  .../dts/aspeed/aspeed-bmc-facebook-yosemite5.dts    | 21 ++++++++++++++++++++-
> >  1 file changed, 20 insertions(+), 1 deletion(-)
> >
> > diff --git a/arch/arm/boot/dts/aspeed/aspeed-bmc-facebook-yosemite5.dts b/arch/arm/boot/dts/aspeed/aspeed-bmc-facebook-yosemite5.dts
> > index 524597a81365ef10cd03b67d35eeb88a965cbe0a..48f864b52d1a22b12f8a39ba9703a90349ed930d 100644
> > --- a/arch/arm/boot/dts/aspeed/aspeed-bmc-facebook-yosemite5.dts
> > +++ b/arch/arm/boot/dts/aspeed/aspeed-bmc-facebook-yosemite5.dts
> > @@ -389,6 +389,25 @@ adc@1d {
> >               ti,mode = /bits/ 8 <1>;
> >       };
> >
> > +     /* PDB IOEXP */
> > +     gpio-expander@24 {
> > +             compatible = "nxp,pca9555";
> > +             reg = <0x24>;
> > +             interrupt-parent = <&sgpiom0>;
> > +             interrupts = <92 IRQ_TYPE_LEVEL_LOW>;
> > +             gpio-controller;
> > +             #gpio-cells = <2>;
> > +             gpio-line-names =
> > +                     "FM_P52V_AUX_FLT_N", "FM_P12V_AUX_PWRGD",
> > +                     "FM_SLOTX_HSC_FAULT_N_FF", "",
> > +                     "","",
> > +                     "","",
> > +                     "PRSNT_FAN0","PRSNT_FAN1",
> > +                     "PRSNT_FAN2","PRSNT_FAN3",
> > +                     "","",
> > +                     "","";
> > +     };
> > +
> >       power-sensor@40 {
> >               compatible = "ti,ina238";
> >               reg = <0x40>;
> > @@ -937,7 +956,7 @@ &sgpiom0 {
> >       "ALERT_OC_PADDLE2_N","",
> >       "ALERT_OC_PWR2_N","",
> >       "ALERT_OC_PWR11_N","",
> > -     "ALERT_PADDLE2_SMB_N","",
> > +     "FM_IOE_ALT_N","",
> >       "ALERT_PWR14_SB2_LEAK_DETECT_N","",
> >       /*bit48-bit55*/
> >       "ALERT_PWR14_SB3_LEAK_DETECT_N","",