dt-bindings: hwmon: pmbus: add bindings for isl68137

Renesas digital multiphase voltage regulators are capable of regulating output voltages that exceed the range that their Vsense pins can detect. In such applications, users may place a voltage divider between Vout and the Vsense pin for a given rail. However, the driver currently has no way of knowing if a voltage divider is being used which results in erroneous telemetry being reported over hwmon.

This patch set defines a devicetree bindings schema for Renesas digital multiphase voltage regulators that are supported by the isl68137 driver to allow users to add voltage divider definitions for any rail powered by the device. This patch set also includes the required changes to the isl68137 driver to enable scaling Vout/Pout telemetry for rails with a defined voltage divider.

v7:
- Port existing device bindings from trivial-bindings.yaml
- Rename new bindings file to isil,isl68137.yaml to match pre-existing bindings
- Style fixes for issues reported by checkpatch --strict

v6:
- Amend patch commit messages to explain why the vout-voltage-divider property was copied from the max20730 instead of using the iio voltage-divider property

v5:
- Fix clang compilation errors related to C23 syntax

v4:
- Revert devicetree property name to "vout-voltage-divider" and refactor property description and driver implementation to match existing vout-voltage-divider implementation in max20730 as no suitable generic voltage divider schema exists.
- Minor fixes based on Guenter's review of v2.
- Initialize voltage dividers for all channels to defaults that simplify logic in PMBus word read/write functions.

v3:
- Report and return errors reading the vout-voltage-divider property from the devicetree when the property is defined
- Change u64 division/rounding operations to use explicit math64 macros

v2:
- Fix devicetree bindings schema errors
- Add "renesas," vendor prefix to "vout-voltage-divider" property
- Rebase patch series on v6.12-rc1

Grant Peltier (2):
hwmon: (pmbus/isl68137) add support for voltage divider on Vout
dt-bindings: hwmon: isl68137: add bindings to support voltage dividers

 .../bindings/hwmon/pmbus/isil,isl68137.yaml   | 148 ++++++++++++
 .../devicetree/bindings/trivial-devices.yaml  |   6 -
 drivers/hwmon/pmbus/isl68137.c                | 210 +++++++++++++++++-
 3 files changed, 353 insertions(+), 11 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/hwmon/pmbus/isil,isl68137.yaml

2.39.5