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

From: Rob Herring
Date: Fri Jan 03 2020 - 18:20:20 EST


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@xxxxxxxxx>
> ---
> .../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@xxxxxxxxx>
> +
> +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
>