Hi,
On 10 Nov 2022 at 21:09, Maxim Mikityanskiy <maxtram95@xxxxxxxxx> wrote:
> A small note on the DMI allow-list: I don't think Z570 is the only
> laptop where EC fails to disable the touchpad. While I would like this
> hack to affect as few laptops as possible, I would expect that other
> similar models produced in the same time period suffer from the same
> issue, and I don't think we have the full list of them.
I just checked Z570 ACPI table, and this is what it does when it receives
VPCCMD_R_TOUCHPAD:
VDAT = TPEN /* \_SB_.PCI0.LPCB.EC0_.TPEN */
If ((TPEN == One))
{
GL04 |= 0x02
}
Else
{
GL04 &= 0xFD
}
VDAT is the data returned to user.
So we can say that TPEN is the logical state of touchpad key, and GL04
is state of touchpad LED or series of LEDs.
VPCCMD_W_TOUCHPAD is nulled, it doesn't work.
I also checked which DSDTs I have (13 DSDTs from 2008 to this year)
contain TPEN, and turned out it was only S12, from 2009. It also had
nulled VPCCMD_W_TOUCHPAD, and returns TPEN on VPCCMD_R_TOUCHPAD, except
it doesn't have an LED or GL04.
So, it's possible that we can only check if TPEN exists on ACPI table,
instead of having a white-list.
-eray
