Re: [PATCH v4 2/4] dt-bindings: regulator: add document bindings for mpq7920

[Rob Herring <robh@kernel.org>]

On Thu, Dec 26, 2019 at 11:29:28PM +0100, Saravanan Sekar wrote:
> Add device tree binding information for mpq7920 regulator driver.
> Example bindings for mpq7920 are added.
> 
> Signed-off-by: Saravanan Sekar <sravanhome@gmail.com>
> ---
>  .../bindings/regulator/mpq7920.yaml           | 143 ++++++++++++++++++

Convention is use the compatible string: mps,mpq7920.yaml

>  1 file changed, 143 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/regulator/mpq7920.yaml
> 
> diff --git a/Documentation/devicetree/bindings/regulator/mpq7920.yaml b/Documentation/devicetree/bindings/regulator/mpq7920.yaml
> new file mode 100644
> index 000000000000..54e9177dfd1b
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/regulator/mpq7920.yaml
> @@ -0,0 +1,143 @@
> +# SPDX-License-Identifier: GPL-2.0

Dual license new bindings:

(GPL-2.0-only OR BSD-2-Clause)

> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/regulator/mpq7920.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Monolithic Power System MPQ7920 PMIC
> +
> +maintainers:
> +  - Saravanan Sekar <sravanhome@gmail.com>
> +
> +properties:
> +  $nodename:
> +    pattern: "pmic@[0-9a-f]{1,2}"
> +  compatible:
> +    enum:
> +      - mps,mpq7920
> +
> +  reg:
> +    maxItems: 1
> +
> +  mps,time-slot:
> +    description:
> +      each regulator output shall be delayed during power on/off sequence which
> +      based on configurable time slot value, must be one of following corresponding
> +      value 0.5ms, 2ms, 8ms, 16ms

These values map to 0-3?

This value is how long each time slot is?

> +    allOf:
> +      - $ref: "/schemas/types.yaml#/definitions/uint8"
> +      - enum: [ 0, 1, 2, 3 ]
> +      - default: 0

Only $ref needs to be under the allOf, so move enum and default to same 
level as allOf.

> +
> +  mps,fixed-on-time:
> +     description:
> +       select power on sequence with fixed time output delay mentioned in
> +       time-slot reg for all the regulators.
> +     type: boolean
> +
> +  mps,fixed-off-time:
> +     description:
> +        select power off sequence with fixed time output delay mentioned in
> +        time-slot reg for all the regulators.
> +     type: boolean
> +
> +  mps,inc-off-time:
> +     description: |
> +        mutually exclusive to mps,fixed-off-time an array of 8, linearly increase
> +        output delay during power off sequence based on factor of time slot/interval
> +        for each regulator.
> +     allOf:
> +       - $ref: "/schemas/types.yaml#/definitions/uint8-array"
> +       - minimum: 0
> +       - maximum: 15
> +       - default: [ 0, 6, 0, 6, 7, 7, 7, 9 ]

Each value corresponds to a regulator? Why not a per regulator property?

> +
> +  mps,inc-on-time:
> +     description: |
> +        mutually exclusive to mps,fixed-on-time an array of 8, linearly increase
> +        output delay during power on sequence based on factor of time slot/interval
> +        for each regulator.
> +     allOf:
> +       - $ref: "/schemas/types.yaml#/definitions/uint8-array"
> +       - minimum: 0
> +       - maximum: 15
> +       - default: [ 0, 6, 0, 6, 7, 7, 7, 9 ]
> +
> +  mps,switch-freq:
> +     description: |
> +        switching frequency must be one of following corresponding value
> +        1.1MHz, 1.65MHz, 2.2MHz, 2.75MHz

Seems like this should be a common property.

> +     allOf:
> +       - $ref: "/schemas/types.yaml#/definitions/uint8"
> +       - enum: [ 0, 1, 2, 3 ]
> +       - default: 2
> +
> +  mps,buck-softstart:
> +     description: |
> +        An array of 4 contains soft start time of each buck, must be one of
> +        following corresponding values 150us, 300us, 610us, 920us
> +     allOf:
> +       - $ref: "/schemas/types.yaml#/definitions/uint8-array"
> +       - enum: [ 0, 1, 2, 3 ]

As this is an array, should be:

items:
  enum: ...

Constraints on the size of the array?

Though again, why not a per regulator property? Also, a fairly common 
thing for buck regulators?

> +       - default: [ 1, 1, 1, 1 ]
> +
> +  mps,buck-ovp:
> +     description: |
> +        An array of 4 contains over voltage protection of each buck, must be
> +        one of above values
> +     allOf:
> +       - $ref: "/schemas/types.yaml#/definitions/uint8-array"
> +       - enum: [ 0, 1 ]
> +       - default: [ 1, 1, 1, 1 ]
> +
> +  mps,buck-phase-delay:
> +     description: |
> +        An array of 4 contains phase delay of each buck must be one of above values
> +        corresponding to 0deg, 90deg, 180deg, 270deg
> +     allOf:
> +       - $ref: "/schemas/types.yaml#/definitions/uint8-array"
> +       - enum: [ 0, 1, 2, 3 ]
> +       - default: [ 0, 0, 1, 1 ]
> +
> +  regulators:
> +    type: object
> +    description:
> +      list of regulators provided by this controller, must be named
> +      after their hardware counterparts BUCK[1-4], one LDORTC, and LDO[2-5]
> +      The valid names for regulators are
> +      buck1, buck2, buck3, buck4, ldortc, ldo2, ldo3, ldo4, ldo5

You need buck[1-4] and ldo(rtc|[2-5]) child nodes defined here which 
reference regulators.yaml.

> +
> +
> +examples:
> +  - |
> +    i2c {
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +
> +        pmic@69 {
> +          compatible = "mps,mpq7920";
> +          reg = <0x69>;
> +
> +          mps,switch-freq = <1>;
> +          mps,buck-softstart = /bits/ 8 <1 2 1 3>;
> +          mps,buck-ovp = /bits/ 8 <1 0 1 1>;
> +
> +          regulators {
> +            buck1 {
> +             regulator-name = "buck1";
> +             regulator-min-microvolt = <400000>;
> +             regulator-max-microvolt = <3587500>;
> +             regulator-min-microamp  = <460000>;
> +             regulator-max-microamp  = <7600000>;
> +             regulator-boot-on;
> +            };
> +
> +            ldo2 {
> +             regulator-name = "ldo2";
> +             regulator-min-microvolt = <650000>;
> +             regulator-max-microvolt = <3587500>;
> +            };
> +         };
> +       };
> +     };
> +...
> -- 
> 2.17.1
>