Re: [PATCH v2 1/2] dt-bindings: display/bridge: lt9211: Add drive-strength-microamp property

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [High] The values for `drive-strength-microamp` are scaled incorrectly by a factor of 100, violating the standard device tree unit suffix.
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commit ab265d46e886455894986f313701d72a9407a58e
Author: Boerge Struempfel <bstruempfel@data-modul.com>

dt-bindings: display/bridge: lt9211: Add drive-strength-microamp property

This commit adds the drive-strength-microamp property to configure the
LT9211 LVDS TX output driver current. It specifies sixteen discrete levels
ranging from 12 to 36.

> diff --git a/Documentation/devicetree/bindings/display/bridge/lontium,lt9211.yaml b/Documentation/devicetree/bindings/display/bridge/lontium,lt9211.yaml
> --- a/Documentation/devicetree/bindings/display/bridge/lontium,lt9211.yaml
> +++ b/Documentation/devicetree/bindings/display/bridge/lontium,lt9211.yaml
[ ... ]
> +  drive-strength-microamp:
> +    description:
> +      LVDS TX output driver current. Sixteen discrete levels are supported,
> +      corresponding to the following nominal values in microamps.
> +    enum: [12, 14, 16, 17, 19, 20, 22, 23, 25, 27, 28, 30, 31, 33, 34, 36]

Are these values scaled incorrectly for a property ending in -microamp?

Properties with the -microamp suffix typically require values in true
microamperes. A standard LVDS driver requires differential currents in the
milliamp range, typically 1.25 mA to 3.59 mA, to generate a standard 350 mV
swing over a 100-ohm termination.

Values from 12 to 36 microamps appear to be physically insufficient for LVDS
signaling.

If the actual intended currents are 1.25 mA to 3.59 mA, shouldn't the enum
values be 1250, 1406, 1562, up to 3594 to accurately reflect true
microamperes?

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Sashiko AI review · https://sashiko.dev/#/patchset/20260513133127.376458-1-bstruempfel@data-modul.com?part=1