Re: [PATCH v3 2/3] platform/arm64: add Lenovo Yoga Slim 7x Gen 11 EC driver

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 2 potential issue(s) to consider:
- [Medium] hwmon: platform EC driver registers hwmon directly instead of using aux device
- [Medium] i2c: device ID name exceeds I2C_NAME_SIZE causing truncation
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commit a7a9ebb5757758e9760736e7550c333cea597cae
Author: Oleg Keri <okerixx@gmail.com>

platform/arm64: add Lenovo Yoga Slim 7x Gen 11 EC driver

This commit adds an embedded controller driver for the Lenovo Yoga Slim
7x Gen 11 laptop. The driver provides thermistors, battery cell voltages,
and CPU fan speed as hwmon channels, alongside keyboard backlight and
hotkey controls.

> diff --git a/drivers/platform/arm64/lenovo-yoga-slim7x-gen11-ec.c b/drivers/platform/arm64/lenovo-yoga-slim7x-gen11-ec.c
> --- /dev/null
> +++ b/drivers/platform/arm64/lenovo-yoga-slim7x-gen11-ec.c

[ ... ]

> +static int yoga_ec_probe(struct i2c_client *client)
> +{

[ ... ]

> +	hwmon = devm_hwmon_device_register_with_info(dev, "yoga_slim7x_ec", ec,
> +						     &yoga_ec_chip_info, NULL);

[Severity: Medium]
Does this code violate the hwmon subsystem guidelines?

The EC driver acts as a platform multi-function device providing hwmon,
input, and LED capabilities, but registers hwmon directly from
drivers/platform/arm64/ inside yoga_ec_probe().

According to the hwmon subsystem guidelines, the hardware monitoring
functionality of a platform multi-function device should be implemented
as an auxiliary device driver residing in drivers/hwmon/ to avoid layering
violations and bypass of maintainer review.

[ ... ]

> +static const struct i2c_device_id yoga_ec_i2c_id[] = {
> +	{ "yoga-slim7x-gen11-ec" },
> +	{ }
> +};

[Severity: Medium]
Can this device ID string cause truncation and matching failures?

The string "yoga-slim7x-gen11-ec" is exactly 20 characters long. Since
I2C_NAME_SIZE is 20, the string literal fully occupies the array without
a null terminator.

During module build, modpost might read past the array generating garbage
for modules.alias. At runtime, the client's name populated from device tree
or ACPI will be truncated to 19 characters plus a null terminator. This
causes i2c_match_id() to fail because it will compare the truncated
runtime string against the unterminated string literal.

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260921144953.15113-1-okerixx@gmail.com?part=2