Re: [PATCH V3 11/17] dt-bindings: arm: mediatek: Add #reset-cells property for MT8192-sys-clock
From: Rex-BC Chen
Date: Tue Apr 26 2022 - 04:29:43 EST
On Mon, 2022-04-25 at 15:44 +0800, Krzysztof Kozlowski wrote:
> On 25/04/2022 04:37, Rex-BC Chen wrote:
> > > > + '#reset-cells':
> > > > + maximum: 2
> > >
> > > Why this is a maximum? Usually this is const, so how do you use
> > > it
> > > (with
> > > what values)?
> > >
> > We need to let the driver compatible with previous setting in
> > drivers/clk/mediatek/reset.c
> Then it should be enum [1, 2], because '0' is not valid.
> > There are two use cases in our reset driver:
> > (Refer to )
> > 1. #reset-cells = <1>
> > When we input the argument, the older driver
> > use is to calculate
> > bank and bit by different method. From the implementation of
> > reset_xlate(), we can see if the argument number is 1, it will
> > return directly.
> I understand this is an old binding with older compatibles, so this
> should be restricted per each variant (allOf:if:then)... but wait,
> binding did not allow any reset-cells! You add an entirely new
> property and already want to support some older (deprecated?) way.
> > 2. #reset-cells = <2>
> > The input arguments is offset and bit. When we input two
> > arguments,
> > we can use reset_xlate() to calculate the corresponding id to
> > assert
> > and deassert.
> > :
> > If it's acceptable, I will add this in commit message.
> Best regards,
I will let #reset-cells = <1> in next version and abandon the
modification of reset_xlate().