Re: [PATCH v7 2/7] dt-bindings: iio: adc: microchip,mcp3564: 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-binding introduces `spi-device-addr` to replace the deprecated `microchip,hw-device-address` and removes it from the required list, but the driver has not been updated to parse the new generic property.
--

--- Patch [2]: [PATCH v7 2/7] dt-bindings: iio: adc: microchip,mcp3564: Add spi-device-addr ---
commit a3bb549053e31953c445885e8d6cb1988514c7b0
Author: Janani Sunil <janani.sunil@analog.com>

dt-bindings: iio: adc: microchip,mcp3564: Add spi-device-addr
    
This commit introduces the generic spi-device-addr property to the mcp3564
binding. It also marks the existing vendor-specific 
microchip,hw-device-address property as deprecated and removes it from the 
required list.

> diff --git a/Documentation/devicetree/bindings/iio/adc/microchip,mcp3564.yaml b/Documentation/devicetree/bindings/iio/adc/microchip,mcp3564.yaml
> index 6753192761971..de1ea289e7f52 100644
> --- a/Documentation/devicetree/bindings/iio/adc/microchip,mcp3564.yaml
> +++ b/Documentation/devicetree/bindings/iio/adc/microchip,mcp3564.yaml
[ ... ]
> @@ -91,6 +92,12 @@ properties:
>        clocking of the device address (BITS[7:6] - top two bits of COMMAND BYTE
>        which is first one on the wire).
>  
> +  spi-device-addr:
> +    maxItems: 1
> +    items:
> +      enum: [0, 1, 2, 3]
> +    default: [1]
> +
>    "#io-channel-cells":
>      const: 1
[ ... ]
> @@ -123,7 +130,6 @@ dependencies:
>  required:
>    - compatible
>    - reg
> -  - microchip,hw-device-address
>    - spi-max-frequency
>  
>  allOf:

[Severity: High]
Since the old microchip,hw-device-address property is removed from the
required list here and replaced by spi-device-addr, does the mcp3564 driver
need an accompanying update to parse the new generic property?

Currently, if a device tree author updates their configuration to use the new
spi-device-addr property following this binding, mcp3564_config() still
explicitly checks only for the deprecated property and will silently fall
back to 0x1:

drivers/iio/adc/mcp3564.c:mcp3564_config() {
	unsigned int tmp = 0x01;
	...
	device_property_read_u32(dev, "microchip,hw-device-address", &tmp);
	...
}

Could this cause hardware state machine initialization and SPI communication
to fail for any device physically strapped to addresses 0, 2, or 3 if they
drop the old property?

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260722-ad5529r-driver-v7-0-7781cd74ad75@analog.com?part=2