[PATCH v8 02/19] pinctrl: nxp: add a pin controller driver based on SCMI pin control protocol

[Peng Fan]

> Subject: Re: [PATCH v8 02/19] pinctrl: nxp: add a pin controller driver
> based on SCMI pin control protocol
> 
> On 3/26/25 2:52 AM, Peng Fan wrote:
> >> Subject: Re: [PATCH v8 02/19] pinctrl: nxp: add a pin controller
> >> driver based on SCMI pin control protocol
> >>
> >> On 3/25/25 9:06 AM, Peng Fan wrote:
> >>
> >> [...]
> >>
> >>>>> diff --git a/include/scmi_protocols.h b/include/scmi_protocols.h
> >>>>> index 7abb2a6f36b..279ebbad440 100644
> >>>>> --- a/include/scmi_protocols.h
> >>>>> +++ b/include/scmi_protocols.h
> >>>>> @@ -24,6 +24,7 @@ enum scmi_std_protocol {
> >>>>>     	SCMI_PROTOCOL_ID_SENSOR = 0x15,
> >>>>>     	SCMI_PROTOCOL_ID_RESET_DOMAIN = 0x16,
> >>>>>     	SCMI_PROTOCOL_ID_VOLTAGE_DOMAIN = 0x17,
> >>>>> +	SCMI_PROTOCOL_ID_PINCTRL = 0x19,
> >>>> If this is the IMX specific pinctrl protocol, please make sure to
> >>>> name it accordingly , SCMI_PROTOCOL_ID_PINCTRL_IMX or
> >> something .
> >>>
> >>> This ID is generic ID, not i.MX specific.
> >>>
> >>> i.MX SCMI pinctrl follows ARM SCMI spec, but i.MX pinctrl bindings
> >> are
> >>> different compared with ARM SCMI generic pinconf bindings, so we
> >> need
> >>> a separate driver for i.MX.
> >> But then, why is it using the same protocol ID ?
> >
> > i.MX System Manager FW pinctrl follows ARM SCMI spec, the ID
> value is
> > 0x19.
> >
> >
> > If you look at linux kernel driver
> >
> > drivers/pinctrl/pinctrl-scmi.c
> > drivers/pinctrl/freescale/pinctrl-scmi-imx.c
> 
> Is the second driver upstream at all ? I don't see it in linux-next ?

Typo: drivers/pinctrl/freescale/pinctrl-imx-scmi.c

> 
> > Both use same ID 0x19.
> >
> > It is fine to use below, if it is fine to you.
> > SCMI_PROTOCOL_ID_PINCTRL_IMX = 0x19.
> How does the kernel discern which driver it should use to
> communicate with the SCMI provider if both drivers are compiled into
> the kernel ?

There is a check in drivers probe. Only one will succeed.

But there is a common issue regarding scmi devlink that I am trying
to resolve.

Regards,
Peng.