Re: [PATCH 1/7] platform/x86: asus-wmi: dump buffer replies in the debugfs dsts file

["Ilpo Järvinen" <ilpo.jarvinen@linux.intel.com>]

On Sun, 1 Nov 2026, Bartu Alev wrote:

> Reading dsts calls asus_wmi_get_devstate(), which uses
> asus_wmi_evaluate_method().  Because that helper handles only
> ACPI_TYPE_INTEGER and leaves other return types zeroed, methods
> returning an ACPI buffer read as 0x0.  This affects fan floor tables
> (0x00110026, 0x00110027, 0x00110033), fan curve getters (0x00110024,
> 0x00110025), and TUF RGB readback (0x0010005B).
> 
> Evaluate the method through asus_wmi_evaluate_method_locked() directly,
> matching the call node, which keeps execution serialized against other
> WMI operations.  Format integer replies as before, dump buffer
> contents with their byte length, and print any other type as t:<type>:
> 
>   DSTS(0x110026) = 16 bytes:
>     00000000: 00 00 00 00 19 30 3a 4a 00 00 00 00 00 00 00 00
> 
> The sentinels 0xfffffffe and 0xffffffff continue to return -ENODEV.
> 
> Signed-off-by: Bartu Alev <bartualev@gmail.com>
> ---
>  drivers/platform/x86/asus-wmi.c | 46 ++++++++++++++++++++++++++++++++++-------
>  1 file changed, 39 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/platform/x86/asus-wmi.c b/drivers/platform/x86/asus-wmi.c
> index b33ebdb21aa21..c55f469cb03dc 100644
> --- a/drivers/platform/x86/asus-wmi.c
> +++ b/drivers/platform/x86/asus-wmi.c
> @@ -5038,16 +5038,48 @@ struct asus_wmi_debugfs_node {
>  static int show_dsts(struct seq_file *m, void *data)
>  {
>  	struct asus_wmi *asus = m->private;
> -	int err;
> -	u32 retval = -1;
> +	struct bios_args args = {
> +		.arg0 = asus->debug.dev_id,
> +	};
> +	struct acpi_buffer input = { (acpi_size) sizeof(args), &args };
> +	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
> +	union acpi_object *obj;
> +	acpi_status status;
> +	u32 retval;
> +	int err = 0;
>  
> -	err = asus_wmi_get_devstate(asus, asus->debug.dev_id, &retval);
> -	if (err < 0)
> -		return err;
> +	status = asus_wmi_evaluate_method_locked(asus->dsts_id, &input, &output);
> +	if (ACPI_FAILURE(status))
> +		return -EIO;
>  
> -	seq_printf(m, "DSTS(%#x) = %#x\n", asus->debug.dev_id, retval);
> +	obj = (union acpi_object *)output.pointer;

Using __free() is preferred. Please also declare the variable here in 
that case.

> +	if (!obj)
> +		return -ENODATA;
>  
> -	return 0;
> +	switch (obj->type) {
> +	case ACPI_TYPE_BUFFER:
> +		seq_printf(m, "DSTS(%#x) = %u bytes:\n", asus->debug.dev_id,
> +			   obj->buffer.length);
> +		seq_hex_dump(m, "  ", DUMP_PREFIX_OFFSET, 16, 1,
> +			     obj->buffer.pointer, obj->buffer.length, false);
> +		break;
> +	case ACPI_TYPE_INTEGER:
> +		retval = (u32)obj->integer.value;
> +		if (retval == ASUS_WMI_UNSUPPORTED_METHOD || retval == (u32)~0)
> +			err = -ENODEV;
> +		else
> +			seq_printf(m, "DSTS(%#x) = %#x\n", asus->debug.dev_id,
> +				   retval);
> +		break;
> +	default:
> +		seq_printf(m, "DSTS(%#x) = t:%d\n", asus->debug.dev_id,
> +			   obj->type);
> +		break;
> +	}
> +
> +	kfree(obj);
> +
> +	return err;
>  }
>  
>  static int show_devs(struct seq_file *m, void *data)
> 
> 

-- 
 i.