Re: Keyboard regression by intel-vbtn

From: Hans de Goede
Date: Wed Sep 30 2020 - 09:28:43 EST


Hi,

On 9/29/20 10:47 PM, Limonciello, Mario wrote:

I requested on the Ubuntu bug for someone to provide these.


Joe Barnett was kind enough to share two ACPI dumps to compare.
Not affected:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1822394/+attachment/5415318/+files/1.2.0.acpidump

Affected:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1822394/+attachment/5415405/+files/1.13.0.acpidump

Thank you, I took a look at these (before completing my allow-list fix),
but there is not really much which stands out. The only related thing which
stands out is that the 1.13.0 dsdt.dsl has this new bit:


Case (0x08)
{
Return (^^PCI0.LPCB.H_EC.VGBI.VGBS ())
}

Inside the _DSM of the HIDD / INT33D5 device.

Method (_DSM, 4, Serialized) // _DSM: Device-Specific Method
{
If ((Arg0 == ToUUID ("eeec56b3-4442-408f-a792-4edd4d758054")))


What is interesting here is that the PCI0.LPCB.H_EC.VGBI.VGBS object/method
does not actually exist the correct path is:

^^PCI0.LPCB.ECDV.VGBI.VGBS

So this does suggest that something around the VGBS handling changed
(and since it points to a non existing ACPI object, possibly broke)
in the newer BIOS version. But what exactly is going on on this XPS 2-in-1
cannot really be derived from the acpidumps.

Regards,

Hans