Re: [PATCH 1/4] dt-bindings: mfd: nxp,bbnsm: Add binding for nxp bbnsm

[Alexandre Belloni <alexandre.belloni@bootlin.com>]

On 21/11/2022 10:09:40+0100, Krzysztof Kozlowski wrote:
> On 21/11/2022 07:51, Jacky Bai wrote:
> > Add binding for NXP BBNSM(Battery-Backed Non-Secure Module).
> > 
> > Signed-off-by: Jacky Bai <ping.bai@nxp.com>
> > ---
> >  .../devicetree/bindings/mfd/nxp,bbnsm.yaml    | 103 ++++++++++++++++++
> >  1 file changed, 103 insertions(+)
> >  create mode 100644 Documentation/devicetree/bindings/mfd/nxp,bbnsm.yaml
> > 
> > diff --git a/Documentation/devicetree/bindings/mfd/nxp,bbnsm.yaml b/Documentation/devicetree/bindings/mfd/nxp,bbnsm.yaml
> > new file mode 100644
> > index 000000000000..b3f22b0daea6
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/mfd/nxp,bbnsm.yaml
> > @@ -0,0 +1,103 @@
> > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/mfd/nxp,bbnsm.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: NXP Battery-Backed Non-Secure Module bindings
> > +
> > +maintainers:
> > +  - Jacky Bai <ping.bai@nxp.com>
> > +
> > +description: |
> > +  NXP BBNSM serves as non-volatile logic and storage for the system.
> > +  it Intergrates RTC & ON/OFF control.
> > +  The RTC can retain its state and continues counting even when the
> > +  main chip is power down. A time alarm is generated once the most
> > +  significant 32 bits of the real-time counter match the value in the
> > +  Time Alarm register.
> > +  The ON/OFF logic inside the BBNSM allows for connecting directly to
> > +  a PMIC or other voltage regulator device. both smart PMIC mode and
> > +  Dumb PMIC mode supported.
> > +
> > +properties:
> > +  compatible:
> > +    items:
> > +      - enum:
> > +          - nxp,bbnsm
> > +      - const: syscon
> > +      - const: simple-mfd
> > +
> > +  reg:
> > +    maxItems: 1
> > +
> > +  rtc:
> > +    type: object
> > +
> > +    properties:
> > +      compatible:
> > +        const: nxp,bbnsm-rtc
> 
> 
> Missing ref to rtc.yaml.
> 

This is also missing start-year

> > +
> > +      regmap:
> 
> Use vendor prefix, descriptive name and description. Where is the type
> of 'regmap' defined?
> 
> > +        maxItems: 1
> 
> I don't think this is correct. Rob explained the simple-mfd means
> children do not depend on anything from the parent, but taking a regmap
> from its parent contradicts it.
> 
> > +
> > +      interrupts:
> > +        maxItems: 1
> 
> You have same interrupt and same address space used by two devices.
> 
> Both arguments (depending on parent regmap, sharing interrupt) suggests
> that this is one device block, so describing it with simple-mfd is quite
> unflexible.
> 
> > +
> > +    required:
> > +      - compatible
> > +      - regmap
> > +      - interrupts
> > +
> > +    additionalProperties: false
> > +
> > +  pwrkey:
> > +    type: object
> > +    $ref: /schemas/input/input.yaml#
> > +
> > +    properties:
> > +      compatible:
> > +        const: nxp,bbnsm-pwrkey
> > +
> > +      regmap:
> > +        maxItems: 1
> > +
> > +      interrupts:
> > +        maxItems: 1
> > +
> > +      linux,code: true
> > +
> > +    required:
> > +      - compatible
> > +      - regmap
> > +      - interrupts
> > +
> > +    additionalProperties: false
> > +
> > +required:
> > +  - compatible
> > +  - reg
> > +  - rtc
> > +  - pwrkey
> > +
> > +additionalProperties: false
> > +
> > +examples:
> > +  - |
> > +    bbnsm: bbnsm@44440000 {
> > +      compatible = "nxp,bbnsm", "syscon", "simple-mfd";
> > +      reg = <0x44440000 0x10000>;
> > +
> > +      bbnsm_rtc: rtc {
> > +        compatible = "nxp,bbnsm-rtc";
> 
> Use 4 spaces for example indentation.
> 
> > +        regmap = <&bbnsm>;
> > +        interrupts = <GIC_SPI 73 IRQ_TYPE_LEVEL_HIGH>;
> > +      };
> > +
> > +      bbnsm_pwrkey: pwrkey {
> > +         compatible = "nxp,bbnsm-pwrkey";
> > +         regmap = <&bbnsm>;
> > +         interrupts = <GIC_SPI 73 IRQ_TYPE_LEVEL_HIGH>;
> > +         linux,code = <KEY_POWER>;
> > +       };
> > +    };
> 
> Best regards,
> Krzysztof
> 

-- 
Alexandre Belloni, co-owner and COO, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com