Re: [PATCH v2 11/12] platform/x86: lenovo-wmi-helpers: Adopt new WMI API

[Armin Wolf <W_Armin@gmx.de>]

Am 09.10.26 um 14:53 schrieb Rong Zhang:

> The new WMI API supports multiple ACPI types by converting them into a
> unified buffer that satisfies alignment and size requirements.
>
> Adopt it to make our life easier.
>
> Note that the Windows WMI-ACPI driver converts all ACPI objects into a
> common buffer format, so adopting the new API intentionally accepts more
> ACPI types as a followup of commit 465dc9da8ff6 ("platform/x86:
> lenovo-wmi-helpers: Convert returned buffer into u32").

Reviewed-by: Armin Wolf <W_Armin@gmx.de>

> Suggested-by: Armin Wolf <W_Armin@gmx.de>
> Link: https://lore.kernel.org/r/f1787927-b655-4321-b9d9-bc12353c72db@gmx.de/
> Signed-off-by: Rong Zhang <i@rong.moe>
> ---
>   drivers/platform/x86/lenovo/wmi-helpers.c | 61 ++++++++++++-------------------
>   1 file changed, 23 insertions(+), 38 deletions(-)
>
> diff --git a/drivers/platform/x86/lenovo/wmi-helpers.c b/drivers/platform/x86/lenovo/wmi-helpers.c
> index 8f5766c391eb..687caa226263 100644
> --- a/drivers/platform/x86/lenovo/wmi-helpers.c
> +++ b/drivers/platform/x86/lenovo/wmi-helpers.c
> @@ -24,9 +24,10 @@
>   #include <linux/export.h>
>   #include <linux/module.h>
>   #include <linux/notifier.h>
> -#include <linux/unaligned.h>
>   #include <linux/wmi.h>
>   
> +#include <asm/byteorder.h>
> +
>   #include "wmi-helpers.h"
>   
>   /* Thermal mode notifier chain. */
> @@ -42,49 +43,33 @@ static BLOCKING_NOTIFIER_HEAD(tm_chain_head);
>    * @size: Length of the buffer.
>    * @retval: Pointer for the return value to be assigned.
>    *
> - * Calls wmidev_evaluate_method for Lenovo WMI devices that return an ACPI
> - * integer. Validates the return value type and assigns the value to the
> - * retval pointer.
> + * Calls the specified WMI method for Lenovo WMI devices that return a WMI
> + * integer. Validates the return value and assigns it to @retval when it's not
> + * NULL, otherwise the return value is not validated.
>    *
>    * 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 };
> -	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;
> -
> -	union acpi_object *ret_obj __free(kfree) = output.pointer;
> -
> -	if (retval) {
> -		if (!ret_obj)
> -			return -ENODATA;
> -
> -		switch (ret_obj->type) {
> -		/*
> -		 * The ACPI method may simply return a buffer when a u32
> -		 * is expected. This is valid on Windows as its WMI-ACPI
> -		 * driver converts everything to a common buffer.
> -		 */
> -		case ACPI_TYPE_BUFFER:
> -			if (ret_obj->buffer.length < sizeof(u32))
> -				return -ENXIO;
> -
> -			*retval = get_unaligned_le32(ret_obj->buffer.pointer);
> -			return 0;
> -		case ACPI_TYPE_INTEGER:
> -			*retval = (u32)ret_obj->integer.value;
> -			return 0;
> -		default:
> -			return -ENXIO;
> -		}
> -	}
> +	struct wmi_buffer input = {
> +		.length = size,
> +		.data = buf,
> +	};
> +	struct wmi_buffer output;
> +	int ret;
> +
> +	if (!retval)
> +		return wmidev_invoke_procedure(wdev, instance, method_id, &input);
> +
> +	ret = wmidev_invoke_method(wdev, instance, method_id, &input,
> +				   &output, sizeof(__le32));
> +	if (ret)
> +		return ret;
> +
> +	__le32 *valp __free(kfree) = output.data;
> +
> +	*retval = le32_to_cpu(*valp);
>   
>   	return 0;
>   };
>