On Mon, 7 Apr 2025, Derek J. Clark wrote:
> Adds lenovo-wmi-helpers, which provides a common wrapper function for
> wmidev_evaluate_method that does data validation and error handling.
>
> Reviewed-by: Mario Limonciello <mario.limonciello@xxxxxxx>
> Signed-off-by: Derek J. Clark <derekjohn.clark@xxxxxxxxx>
> ---
> v5:
> - Fixes from v4 review.
> - Combine all previous methods into a single function that takes a
> buffer for the wmi method arguments.
> v4:
> - Changed namespace to LENOVO_WMI_HELPERS from LENOVO_WMI.
> - Changed filenames to lenovo-wmi-helpers from lenovo-wmi.
> - Removed structs and functions implemented by other drivers.
> ---
> MAINTAINERS | 2 +
> drivers/platform/x86/Kconfig | 4 ++
> drivers/platform/x86/Makefile | 1 +
> drivers/platform/x86/lenovo-wmi-helpers.c | 74 +++++++++++++++++++++++
> drivers/platform/x86/lenovo-wmi-helpers.h | 20 ++++++
> 5 files changed, 101 insertions(+)
> create mode 100644 drivers/platform/x86/lenovo-wmi-helpers.c
> create mode 100644 drivers/platform/x86/lenovo-wmi-helpers.h
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 675f4b26426d..3a370a18b806 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -13164,6 +13164,8 @@ L: platform-driver-x86@xxxxxxxxxxxxxxx
> S: Maintained
> F: Documentation/wmi/devices/lenovo-wmi-gamezone.rst
> F: Documentation/wmi/devices/lenovo-wmi-other.rst
> +F: drivers/platform/x86/lenovo-wmi-helpers.c
> +F: drivers/platform/x86/lenovo-wmi-helpers.h
>
> LENOVO WMI HOTKEY UTILITIES DRIVER
> M: Jackie Dong <xy-jackie@xxxxxxx>
> diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
> index 43407e76476b..bece1ba61417 100644
> --- a/drivers/platform/x86/Kconfig
> +++ b/drivers/platform/x86/Kconfig
> @@ -459,6 +459,10 @@ config IBM_RTL
> state = 0 (BIOS SMIs on)
> state = 1 (BIOS SMIs off)
>
> +config LENOVO_WMI_HELPERS
> + tristate
> + depends on ACPI_WMI
> +
> config IDEAPAD_LAPTOP
> tristate "Lenovo IdeaPad Laptop Extras"
> depends on ACPI
> diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile
> index 650dfbebb6c8..5a9f4e94f78b 100644
> --- a/drivers/platform/x86/Makefile
> +++ b/drivers/platform/x86/Makefile
> @@ -69,6 +69,7 @@ obj-$(CONFIG_THINKPAD_LMI) += think-lmi.o
> obj-$(CONFIG_YOGABOOK) += lenovo-yogabook.o
> obj-$(CONFIG_YT2_1380) += lenovo-yoga-tab2-pro-1380-fastcharger.o
> obj-$(CONFIG_LENOVO_WMI_CAMERA) += lenovo-wmi-camera.o
> +obj-$(CONFIG_LENOVO_WMI_HELPERS) += lenovo-wmi-helpers.o
>
> # Intel
> obj-y += intel/
> diff --git a/drivers/platform/x86/lenovo-wmi-helpers.c b/drivers/platform/x86/lenovo-wmi-helpers.c
> new file mode 100644
> index 000000000000..166e87fef156
> --- /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@xxxxxxxxx>
> + */
> +
> +#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.
> + *
> + * Return: 0 on success, or on error.
The second part either has a typo (on -> an ?) or is grammaritically
incomplete (what is returned on error ?). Although I think if it's the
first option, it should say e.g. "an error code." not just "an error."
> + */
> +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;
> +};
> +EXPORT_SYMBOL_NS_GPL(lwmi_dev_evaluate_int, "LENOVO_WMI_HELPERS");
> +
> +MODULE_AUTHOR("Derek J. Clark <derekjohn.clark@xxxxxxxxx>");
> +MODULE_DESCRIPTION("Lenovo WMI Helpers Driver");
> +MODULE_LICENSE("GPL");
> diff --git a/drivers/platform/x86/lenovo-wmi-helpers.h b/drivers/platform/x86/lenovo-wmi-helpers.h
> new file mode 100644
> index 000000000000..b76633603dcc
> --- /dev/null
> +++ b/drivers/platform/x86/lenovo-wmi-helpers.h
> @@ -0,0 +1,20 @@
> +/* SPDX-License-Identifier: GPL-2.0-or-later */
> +
> +/* Copyright(C) 2025 Derek J. Clark <derekjohn.clark@xxxxxxxxx> */
> +
> +#ifndef _LENOVO_WMI_HELPERS_H_
> +#define _LENOVO_WMI_HELPERS_H_
> +
> +#include <linux/types.h>
> +
> +struct wmi_device;
> +
> +struct wmi_method_args_32 {
> + u32 arg0;
> + u32 arg1;
> +};
> +
> +int lwmi_dev_evaluate_int(struct wmi_device *wdev, u8 instance, u32 method_id,
> + unsigned char *buf, size_t size, u32 *retval);
> +
> +#endif /* !_LENOVO_WMI_HELPERS_H_ */
>
--
i.
