Re: [PATCH V2] dt-bindings: watchdog: brcm,bcm7038: add more compatible strings

[Rafał Miłecki <zajec5@xxxxxxxxx>]

On 9.02.2022 20:09, Rob Herring wrote:
> On Wed, Jan 26, 2022 at 11:20:34PM +0100, Rafał Miłecki wrote:
> > From: Rafał Miłecki <rafal@xxxxxxxxxx>
> >
> > This hardware block is used on almost all BCM63xx family chipsets and
> > BCM4908 which reuses a lot of BCM63xx parts. Add relevant compatible
> > strings and also include a generic one.
> >
> > The only SoC with a different block I found is BCM6838 (thus not included
> > in this change).
> >
> > It may be worth noting that BCM6338, BCM6345, BCM6348 and BCM63268 don't
> > include "SoftRst" register but that can be handled by drivers based on
> > precise compatible string.
> >
> > Signed-off-by: Rafał Miłecki <rafal@xxxxxxxxxx>
> > ---
> > V2: Sort enum entries & update brcm,twd.yaml
> > ---
> >   .../devicetree/bindings/mfd/brcm,twd.yaml     |  2 +-
> >   .../bindings/watchdog/brcm,bcm7038-wdt.yaml   | 21 +++++++++++++++----
> >   2 files changed, 18 insertions(+), 5 deletions(-)
> >
> > diff --git a/Documentation/devicetree/bindings/mfd/brcm,twd.yaml b/Documentation/devicetree/bindings/mfd/brcm,twd.yaml
> > index 634526f790b8..3f5db1990aba 100644
> > --- a/Documentation/devicetree/bindings/mfd/brcm,twd.yaml
> > +++ b/Documentation/devicetree/bindings/mfd/brcm,twd.yaml
> > @@ -55,7 +55,7 @@ examples:
> >           #size-cells = <1>;
> >   
> >           watchdog@28 {
> > -            compatible = "brcm,bcm7038-wdt";
> > +            compatible = "brcm,bcm4908-wdt", "brcm,bcm63xx-wdt";
> >               reg = <0x28 0x8>;
> >           };
> >       };
> > diff --git a/Documentation/devicetree/bindings/watchdog/brcm,bcm7038-wdt.yaml b/Documentation/devicetree/bindings/watchdog/brcm,bcm7038-wdt.yaml
> > index a926809352b8..4d848442913c 100644
> > --- a/Documentation/devicetree/bindings/watchdog/brcm,bcm7038-wdt.yaml
> > +++ b/Documentation/devicetree/bindings/watchdog/brcm,bcm7038-wdt.yaml
> > @@ -16,9 +16,22 @@ maintainers:
> >   
> >   properties:
> >     compatible:
> > -    enum:
> > -      - brcm,bcm6345-wdt
> > -      - brcm,bcm7038-wdt
> > +    items:
> > +      - enum:
> > +          - brcm,bcm4908-wdt
> > +          - brcm,bcm6338-wdt
> > +          - brcm,bcm6345-wdt
> > +          - brcm,bcm6348-wdt
> > +          - brcm,bcm6848-wdt
> > +          - brcm,bcm6858-wdt
> > +          - brcm,bcm7038-wdt
> > +          - brcm,bcm60333-wdt
> > +          - brcm,bcm63138-wdt
> > +          - brcm,bcm63148-wdt
> > +          - brcm,bcm63268-wdt
> > +          - brcm,bcm63381-wdt
> > +          - brcm,bcm68360-wdt
> > +      - const: brcm,bcm63xx-wdt
>
> Is it really worthwhile to update all these DTs?:
>
> arch/mips/boot/dts/brcm/bcm63268.dtsi:                  compatible = "brcm,bcm7038-wdt";
> arch/mips/boot/dts/brcm/bcm6328.dtsi:                   compatible = "brcm,bcm7038-wdt";
> arch/mips/boot/dts/brcm/bcm6358.dtsi:                   compatible = "brcm,bcm7038-wdt";
> arch/mips/boot/dts/brcm/bcm6362.dtsi:                   compatible = "brcm,bcm7038-wdt";
> arch/mips/boot/dts/brcm/bcm6368.dtsi:                   compatible = "brcm,bcm7038-wdt";
> arch/mips/boot/dts/brcm/bcm7125.dtsi:                   compatible = "brcm,bcm7038-wdt";
> arch/mips/boot/dts/brcm/bcm7346.dtsi:                   compatible = "brcm,bcm7038-wdt";
> arch/mips/boot/dts/brcm/bcm7358.dtsi:                   compatible = "brcm,bcm7038-wdt";
> arch/mips/boot/dts/brcm/bcm7360.dtsi:                   compatible = "brcm,bcm7038-wdt";
> arch/mips/boot/dts/brcm/bcm7362.dtsi:                   compatible = "brcm,bcm7038-wdt";
> arch/mips/boot/dts/brcm/bcm7420.dtsi:                   compatible = "brcm,bcm7038-wdt";
> arch/mips/boot/dts/brcm/bcm7425.dtsi:                   compatible = "brcm,bcm7038-wdt";
> arch/mips/boot/dts/brcm/bcm7435.dtsi:                   compatible = "brcm,bcm7038-wdt";

I don't have problem handling that.


> I don't think so.
So what's the policy for such bindings then? How to select SoCs that
should have their own bindings? How can I tell which should /borrow/ a
binding instead?

I assumed we want binding per SoC based on the
17fffe91ba36 ("dt-bindings: watchdog: Add BCM6345 compatible to BCM7038 binding")
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=17fffe91ba36d11c7b17be154ecc7c1ed31527eb