Re: [PATCH 02/13] dt-bindings: i2c: nomadik: add mobileye,eyeq5-i2c bindings and example

Théo Lebrun
2024-02-16T10:18:58Z

Hello,

On Fri Feb 16, 2024 at 3:22 AM CET, Rob Herring wrote:
> On Thu, Feb 15, 2024 at 05:52:09PM +0100, Théo Lebrun wrote:
> > Add EyeQ5 bindings to the existing Nomadik I2C dt-bindings. Add the two
> > EyeQ5-specific properties behind a conditional. Add an example for this
> > compatible.

[...]

> > +allOf:
> > + - $ref: /schemas/i2c/i2c-controller.yaml#
> > + - if:
> > + properties:
> > + compatible:
> > + contains:
> > + const: mobileye,eyeq5-i2c
> > + then:
> > + properties:
> > + mobileye,olb:
> > + $ref: /schemas/types.yaml#/definitions/phandle
> > + description: A phandle to the OLB syscon.
>
> Define properties at the top-level and then restrict them in if/then
> schemas.

Noted, thanks.

> > + mobileye,id:
> > + $ref: /schemas/types.yaml#/definitions/uint32
> > + description: Platform-wide controller ID (integer starting from zero).
>
> instance indexes are a NAK. You can use i2cN aliases if you must.
>
> Why do you need it? To access OLB? If so, add cell args to the OLB
> phandle instead.

Why we do what we do: I2C controller must write a 2 bit value depending
on the bus speed. All I2C controllers write into the same register.
Index is used to compute the shift.

mobileye,olb is a phandle to a syscon. I'll be using i2cN aliases I
guess.

Thanks,

--
Théo Lebrun, Bootlin
Embedded Linux and Kernel engineering