Hi,
Firstly, apologies if I have included/excluded the wrong mailing list or
persons in this email. This is my first time doing this and I've tried
my best to make sure it is accurate.
I am facing a regression in the mainline of the kernel (commit
0457e5153e0e8420134f60921349099e907264ca) with the asus-wmi platform
driver. The driver fails to load with the following dmesg:
asus-nb-wmi: probe of asus-nb-wmi failed with error -61
I have an ASUS TUF FX506 laptop.
I traced the regression to the method fan_curve_get_factory_default. It
calls a WMI method which is expected to return a data buffer. However,
if the device does not support fan curve method it is supposed to return
the integer error code ASUS_WMI_UNSUPPORTED_METHOD.
However, my laptop returns a value 0 to indicate that the method is not
supported:
If ((IIA0 == 0x00110024))
{
Return (Zero)
}
If ((IIA0 == 0x00110025))
{
Return (Zero)
}
This means that on lines 395-407 in the method
asus_wmi_evaluate_method_buf, the if condition err == 0 evaluates to
true an -ENODATA (-61) is returned.
case ACPI_TYPE_INTEGER:
err = (u32)obj->integer.value;
if (err == ASUS_WMI_UNSUPPORTED_METHOD)
err = -ENODEV;
/*
* At least one method returns a 0 with no buffer if no arg
* is provided, such as ASUS_WMI_DEVID_CPU_FAN_CURVE
*/
if (err == 0)
err = -ENODATA;
break;
I am not sure the extent of ASUS laptops that are affected. TUF series
laptops do not support fan curve control and so I presume many of them
are affected by this regression.
I have tested a patch which selectively ignores the -ENODATA error code
when probing for fan curve control. However, I'm not sure if this is the
right way to do things and hence have no included the patch here.
Once again, I apologize if this email is not how things are normally
done and would love to hear feedback on the same.
Thanks
Abhijeet
