RE: [PATCH v16 1/3] dt-bindings: i2c: aspeed: support for AST2600-i2cv2

From: Ryan Chen
Date: Wed Mar 19 2025 - 07:26:03 EST


> Subject: Re: [PATCH v16 1/3] dt-bindings: i2c: aspeed: support for
> AST2600-i2cv2
>
> On 17/03/2025 10:21, Ryan Chen wrote:
> >> Neither this.
> >>
> >> So it seems you describe already existing and documented I2C, but for
> >> some reason you want second compatible. The problem is that you do
> >> not provide reason from the point of view of bindings.
> >>
> >> To summarize: what your users want - don't care. Start properly
> >> describing hardware and your SoC.
> >
> > OK, for ast2600 i2c controller have two register mode setting.
> > One, I call it is old register setting, that is right now i2c-aspeed.c
> > .compatible = "aspeed,ast2600-i2c-bus", And there have a global register
> that can set i2c controller as new mode register set.
> > That I am going to drive. That I post is all register in new an old register list.
> >
> > For example,
> > Global register [2] = 0 => i2c present as old register set Global
> > register [2] = 1 => i2c present as new register set
> It's the same device though, so the same compatible.

Sorry, it is different design, and it share the same register space.
So that the reason add new compatible "aspeed,ast2600-i2cv2" for this driver.
It is different register layout.


>
> Best regards,
> Krzysztof