Re: [PATCH v7 4/7] dt-bindings: iio: adc: microchip,mcp3911: Add spi-device-addr

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [High] The dt-bindings update deprecates `microchip,device-addr` in favor of the new generic `spi-device-addr` property, but the `mcp3911` driver was not updated to parse it. If a device tree uses the newly recommended `spi-device-addr` property, the driver will fail to parse it, fall back to device address 0, and fail to communicate with hardware configured for other addresses.
--

--- Patch [4]: [PATCH v7 4/7] dt-bindings: iio: adc: microchip,mcp3911: Add spi-device-addr ---
commit 9e6e246369fd97fd7587432780e30a16297f1eb0
Author: Janani Sunil <janani.sunil@analog.com>
dt-bindings: iio: adc: microchip,mcp3911: Add spi-device-addr

This commit adds the generic spi-device-addr property to the binding.
It also deprecates the existing vendor-specific microchip,device-addr
property.

> diff --git a/Documentation/devicetree/bindings/iio/adc/microchip,mcp3911.yaml b/Documentation/devicetree/bindings/iio/adc/microchip,mcp3911.yaml
> index 3a69ec60edb91..36da2bee1db28 100644
> --- a/Documentation/devicetree/bindings/iio/adc/microchip,mcp3911.yaml
> +++ b/Documentation/devicetree/bindings/iio/adc/microchip,mcp3911.yaml
> @@ -57,6 +57,13 @@ properties:
>      $ref: /schemas/types.yaml#/definitions/uint32
>      enum: [0, 1, 2, 3]
>      default: 0
> +    deprecated: true
> +
> +  spi-device-addr:
> +    maxItems: 1
> +    items:
> +      enum: [0, 1, 2, 3]
> +    default: [0]

[Severity: High]
Is the driver updated to parse this new property?

Looking at mcp3911_probe() in drivers/iio/adc/mcp3911.c, the driver only
handles the deprecated properties:

	ret = device_property_read_u32(dev, "microchip,device-addr", &adc->dev_addr);
	if (ret)
		device_property_read_u32(dev, "device-addr", &adc->dev_addr);

If a modernized device tree uses the newly recommended spi-device-addr
property instead of microchip,device-addr, will the driver fail to parse it
and leave adc->dev_addr at 0?

Could this cause communication failures with hardware configured for non-zero
addresses?

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260722-ad5529r-driver-v7-0-7781cd74ad75@analog.com?part=4