Re: [PATCH v5 2/3] dt-bindings: hwmon: pmbus: add MPS MPQ8646 binding

From: Krzysztof Kozlowski

Date: Mon Jul 27 2026 - 03:14:31 EST


On Fri, Jul 24, 2026 at 01:55:28AM +0200, Vincent Jardin wrote:
> Add a device-tree binding for the Monolithic Power Systems
> MPQ8646 step-down converter as a PMBus device.
>
> The schema is inspired from the mpq8785e:
> same mps,vout-fb-divider-ratio-permille property (maximum: 2047),
> and const: mps,mpq8646.
>
> Signed-off-by: Vincent Jardin <vjardin@xxxxxxx>

A nit, subject: drop second/last, redundant "binding". The
"dt-bindings" prefix is already stating that these are bindings.
See also:
https://elixir.bootlin.com/linux/v7.1-rc7/source/Documentation/devicetree/bindings/submitting-patches.rst#L23

> ---
> .../bindings/hwmon/pmbus/mps,mpq8646.yaml | 50 ++++++++++++++++++++++
> 1 file changed, 50 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/hwmon/pmbus/mps,mpq8646.yaml b/Documentation/devicetree/bindings/hwmon/pmbus/mps,mpq8646.yaml
> new file mode 100644
> index 000000000000..7acf4f235b12
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/hwmon/pmbus/mps,mpq8646.yaml
> @@ -0,0 +1,50 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +# Copyright (c) 2026 Free Mobile - Vincent Jardin <vjardin@xxxxxxx>
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/hwmon/pmbus/mps,mpq8646.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Monolithic Power Systems MPQ8646 PMBus Step-Down Converter (extended)
> +
> +maintainers:
> + - Vincent Jardin <vjardin@xxxxxxx>
> +
> +description: |

Do not need '|' unless you need to preserve formatting.

> + MPS MPQ8646 PMBus step-down converter.
> +
> +properties:
> + compatible:
> + const: mps,mpq8646
> +
> + reg:
> + maxItems: 1
> +
> + mps,vout-fb-divider-ratio-permille:
> + description:
> + The feedback resistor divider ratio, expressed in permille
> + (Vfb / Vout * 1000). This value is written to the
> + PMBUS_VOUT_SCALE_LOOP register and is required for correct output
> + voltage presentation.
> + $ref: /schemas/types.yaml#/definitions/uint32
> + minimum: 1
> + maximum: 2047
> + default: 706

Everything is the same as mps,mpq8785.yam, so why it cannot be added
there? Just grow the list of if:then: to cover your specific
constraints.

Even default is the same... I do not get why looking at other schema
which combines different devices with same default and same maximum
value, you still decided to create a new file.

Best regards,
Krzysztof