xref: /kernel/linux/linux-6.6/Documentation/devicetree/bindings/regulator/rohm,bd71847-regulator.yaml

# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
%YAML 1.2
---
$id: http://devicetree.org/schemas/regulator/rohm,bd71847-regulator.yaml#
$schema: http://devicetree.org/meta-schemas/core.yaml#

title: ROHM BD71847 and BD71850 Power Management Integrated Circuit regulators

maintainers:
  - Matti Vaittinen <mazziesaccount@gmail.com>

description: |
  List of regulators provided by this controller. BD71847 regulators node
  should be sub node of the BD71847 MFD node. See BD71847 MFD bindings at
  Documentation/devicetree/bindings/mfd/rohm,bd71847-pmic.yaml
  Regulator nodes should be named to BUCK_<number> and LDO_<number>. The
  definition for each of these nodes is defined using the standard
  binding for regulators at
  Documentation/devicetree/bindings/regulator/regulator.txt.
  Note that if BD71847 starts at RUN state you probably want to use
  regulator-boot-on at least for BUCK5. LDO6 is supplied by it and it must
  not be disabled by driver at startup. If BUCK5 is disabled at startup the
  voltage monitoring for LDO5/LDO6 can cause PMIC to reset.

# The valid names for BD71847 regulator nodes are:
# BUCK1, BUCK2, BUCK3, BUCK4, BUCK5, BUCK6
# LDO1, LDO2, LDO3, LDO4, LDO5, LDO6

patternProperties:
  "^LDO[1-6]$":
    type: object
    $ref: regulator.yaml#
    description:
      Properties for single LDO regulator.

    properties:
      regulator-name:
        pattern: "^ldo[1-6]$"
        description:
          should be "ldo1", ..., "ldo6"

    unevaluatedProperties: false

  "^BUCK[1-6]$":
    type: object
    $ref: regulator.yaml#
    description:
      Properties for single BUCK regulator.

    properties:
      regulator-name:
        pattern: "^buck[1-6]$"
        description:
          should be "buck1", ..., "buck6"

      rohm,dvs-run-voltage:
        $ref: /schemas/types.yaml#/definitions/uint32
        minimum: 0
        maximum: 1300000
        description:
          PMIC default "RUN" state voltage in uV. See below table for
          bucks which support this. 0 means disabled.

      rohm,dvs-idle-voltage:
        $ref: /schemas/types.yaml#/definitions/uint32
        minimum: 0
        maximum: 1300000
        description:
          PMIC default "IDLE" state voltage in uV. See below table for
          bucks which support this. 0 means disabled.

      rohm,dvs-suspend-voltage:
        $ref: /schemas/types.yaml#/definitions/uint32
        minimum: 0
        maximum: 1300000
        description:
          PMIC default "SUSPEND" state voltage in uV. See below table for
          bucks which support this. 0 means disabled.

        # Supported default DVS states:
        #
        # BD71847:
        # buck | dvs-run-voltage | dvs-idle-voltage | dvs-suspend-voltage
        # ----------------------------------------------------------------
        # 1    | supported       | supported        | supported
        # ----------------------------------------------------------------
        # 2    | supported       | supported        | not supported
        # ----------------------------------------------------------------
        # rest | not supported   | not supported    | not supported

      # BD718(47/50) power outputs can either be controlled by the PMIC internal
      # hardware state machine or by software. If you need regulators to be
      # turned ON/OFF for example based on PMIC_STBY_REQ line (which toggles
      # PMIC HW state machine) - then you should set this property.
      # Tradeoff is that then SW can't control the ON/OFF state for this
      # regulator (other than invoking a PMIC state change).
      rohm,no-regulator-enable-control:
        description: |
          Enable/Disable control of this regulator must be left to the
          PMIC hardware state machine.
        type: boolean

      # Setups where regulator (especially the buck8) output voltage is scaled
      # by adding external connection where some other regulator output is
      # connected to feedback-pin (over suitable resistors) is getting popular
      # amongst users of BD71837. (This allows for example scaling down the
      # buck8 voltages to suit lover GPU voltages for projects where buck8 is
      # (ab)used to supply power for GPU.
      #
      # So we allow describing this external connection from DT and scale the
      # voltages accordingly. This is what the connection should look like:
      #
      # |---------------|
      # |       buck 8  |-------+----->Vout
      # |               |       |
      # |---------------|       |
      #        |                |
      #        |                |
      #        +-------+--R2----+
      #                |
      #                R1
      #                |
      #        V FB-pull-up
      #
      # Here the buck output is sifted according to formula:
      #
      # Vout_o = Vo - (Vpu - Vo)*R2/R1
      # Linear_step = step_orig*(R1+R2)/R1
      #
      # where:
      # Vout_o is adjusted voltage output at vsel reg value 0
      # Vo is original voltage output at vsel reg value 0
      # Vpu is the pull-up voltage V FB-pull-up in the picture
      # R1 and R2 are resistor values.

      rohm,fb-pull-up-microvolt:
        description:
          Feedback-pin has pull-up connection to adjust voltage range. This is
          the used pull-up voltage before R1.

      rohm,feedback-pull-up-r1-ohms:
        description:
          Feedback-pin has pull-up connection to adjust voltage range. This is
          the used R1 resistor.

      rohm,feedback-pull-up-r2-ohms:
        description:
          Feedback-pin has pull-up connection to adjust voltage range. This is
          the used R2 resistor.

    required:
      - regulator-name

    unevaluatedProperties: false

additionalProperties: false