Re: [PATCH v6 2/6] platform/x86: Add Lenovo WMI Helpers

[ALOK TIWARI <alok.a.tiwari@oracle.com>]

> diff --git a/drivers/platform/x86/lenovo-wmi-helpers.c b/drivers/platform/x86/lenovo-wmi-helpers.c
> new file mode 100644
> index 000000000000..2df0408e2a9c
> --- /dev/null
> +++ b/drivers/platform/x86/lenovo-wmi-helpers.c
> @@ -0,0 +1,74 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + * Lenovo Legion WMI helpers driver.
> + *
> + * The Lenovo Legion WMI interface is broken up into multiple GUID interfaces
> + * that require cross-references between GUID's for some functionality. The
> + * "Custom Mode" interface is a legacy interface for managing and displaying
> + * CPU & GPU power and hwmon settings and readings. The "Other Mode" interface
> + * is a modern interface that replaces or extends the "Custom Mode" interface
> + * methods. The "Gamezone" interface adds advanced features such as fan
> + * profiles and overclocking. The "Lighting" interface adds control of various
> + * status lights related to different hardware components. Each of these
> + * drivers uses a common procedure to get data from the WMI interface,
> + * enumerated here.
> + *
> + * Copyright(C) 2025 Derek J. Clark <derekjohn.clark@gmail.com>
> + */

add a space after "Copyright" before "(C)".
Copyright (C) 2025

> +
> +#include <linux/acpi.h>
> +#include <linux/cleanup.h>
> +#include <linux/errno.h>
> +#include <linux/export.h>
> +#include <linux/module.h>
> +#include <linux/wmi.h>
> +
> +#include "lenovo-wmi-helpers.h"
> +
> +/**
> + * lwmi_dev_evaluate_int() - Helper function for calling WMI methods that
> + * return an integer.
> + * @wdev: Pointer to the WMI device to be called.
> + * @instance: Instance of the called method.
> + * @method_id: WMI Method ID for the method to be called.
> + * @buf: Buffer of all arguments for the given method_id.
> + * @size: Length of the buffer.
> + * @retval: Pointer for the return value to be assigned.
> + *
> + * Calls wmidev_valuate_method for Lenovo WMI devices that return an ACPI
> + * integer. Validates the return value type and assigns the value to the
> + * retval pointer.

assuming you meant to refer to wmidev_evaluate_method, the real function
typo wmidev_valuate_method -> wmidev_evaluate_method

> + *
> + * Return: 0 on success, or an error code.
> + */
> +int lwmi_dev_evaluate_int(struct wmi_device *wdev, u8 instance, u32 method_id,
> +			  unsigned char *buf, size_t size, u32 *retval)
> +{
> +	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
> +	union acpi_object *ret_obj __free(kfree) = NULL;
> +	struct acpi_buffer input = { size, buf };
> +	acpi_status status;
> +
> +	status = wmidev_evaluate_method(wdev, instance, method_id, &input,
> +					&output);
> +
> +	if (ACPI_FAILURE(status))
> +		return -EIO;
> +
> +	if (retval) {
> +		ret_obj = output.pointer;
> +		if (!ret_obj)
> +			return -ENODATA;
> +
> +		if (ret_obj->type != ACPI_TYPE_INTEGER)
> +			return -ENXIO;
> +
> +		*retval = (u32)ret_obj->integer.value;
> +	}
> +	return 0;
> +};

Thanks,
Alok