Re: [PATCH v11 5/5] iio: adc: versal-sysmon: add oversampling support

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] Missing hardware synchronization for oversampling ratio caches during initialization.
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commit 25a143792e9062675e1abe4133ac067208b02232
Author: Salih Erim <salih.erim@amd.com>

iio: adc: versal-sysmon: add oversampling support

Add support for reading and writing the oversampling ratio through the IIO
oversampling_ratio attribute. The hardware supports averaging 2, 4, 8, or 16
samples, plus a ratio of 1 (no averaging).

> diff --git a/drivers/iio/adc/versal-sysmon-core.c b/drivers/iio/adc/versal-sysmon-core.c
> index 8f2c502d9cb6d..1b55d343982ef 100644
> --- a/drivers/iio/adc/versal-sysmon-core.c
> +++ b/drivers/iio/adc/versal-sysmon-core.c
[ ... ]
> @@ -846,6 +999,8 @@ int devm_versal_sysmon_core_probe(struct device *dev, struct regmap *regmap)
>  
>  	sysmon = iio_priv(indio_dev);
>  	sysmon->regmap = regmap;
> +	sysmon->temp_oversampling = 1;
> +	sysmon->supply_oversampling = 1;

[Severity: Medium]
Could this lead to a mismatch between the software cache and the hardware
state if the bootloader or firmware previously configured a non-default
oversampling ratio?

Since the driver initializes temp_oversampling and supply_oversampling to 1
without reading the initial state from the hardware or forcing the hardware
registers to match the defaults, userspace might read an oversampling ratio
of 1 via sysfs while the hardware is actually still actively averaging
multiple samples.

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Sashiko AI review · https://sashiko.dev/#/patchset/20260623014036.3865402-1-salih.erim@amd.com?part=5