Re: "EC: Install address space handler at the namespace root" causing issues for some users

[Hans de Goede <hdegoede@redhat.com>]

Hi,

On 8/1/24 4:28 PM, Hans de Goede wrote:
> Hi,
> 
> On 7/29/24 1:15 PM, Hans de Goede wrote:
>> Hi Rafael,
>>
>> There are 2 bug reports:
>>
>> 1. Brightness up/down key-presses no longer working on LG laptop (acpi-video related):
>> https://lists.fedoraproject.org/archives/list/devel@lists.fedoraproject.org/thread/V2KWAGZIAX4TOWPCH6A6FSIT66PR3KMZ/
> 
> I have filed:
> 
> https://bugzilla.redhat.com/show_bug.cgi?id=2302253
> 
> to track this now and an acpidump of the troublesome LG laptop
> is attached there. I have also requested dmesg output of
> a non working kernel to be attached there.
> 
> As a reminder this is the bug where it has been confirmed that
> reverting "EC: Install address space handler at the namespace root"
> helps, with the caveat that there is a Thunderbolt related IRQ
> storm on the ACPI event IRQ after the revert ...

Ok, so the bugzilla now has 2 different dmesg outputs:

1. 6.9.6, this kernel works without problems

2. 6.9.12 with the following patch you suggested on top:

--- a/drivers/acpi/ec.c
+++ b/drivers/acpi/ec.c
@@ -1788,7 +1788,7 @@ void __init acpi_ec_dsdt_probe(void)
 	 * At this point, the GPE is not fully initialized, so do not to
 	 * handle the events.
 	 */
-	ret = acpi_ec_setup(ec, NULL, true);
+	ret = acpi_ec_setup(ec, NULL, false);
 	if (ret) {
 		acpi_ec_free(ec);
 		return;

Unfortunately this does not help. dmesg shows some EC _REG errors, which
are now (with the above diff applied) shown just before the
"Boot DSDT EC initialization complete" message, which shows that _REG now
runs from acpi_ec_add() rather then before:

[    1.007566] ACPI BIOS Error (bug): Could not resolve symbol [\_TZ.FN00._OFF], AE_NOT_FOUND (20230628/psargs-330)
[    1.007576] ACPI Error: Aborting method \_SB.PC00.LPCB.H_EC.EREG due to previous error (AE_NOT_FOUND) (20230628/psparse-52
[    1.007580] ACPI Error: Aborting method \_SB.PC00.LPCB.H_EC._REG due to previous error (AE_NOT_FOUND) (20230628/psparse-52
[    1.007639] ACPI: EC: interrupt unblocked
[    1.007640] ACPI: EC: event unblocked
[    1.007675] ACPI: EC: EC_CMD/EC_SC=0x66, EC_DATA=0x62
[    1.007676] ACPI: EC: GPE=0x6e
[    1.007677] ACPI: \_SB_.PC00.LPCB.LGEC: Boot DSDT EC initialization complete
[    1.007679] ACPI: \_SB_.PC00.LPCB.LGEC: EC: Used to handle transactions and events

Note that the errors are from calling _REG on \_SB.PC00.LPCB.H_EC, where as the actual
EC (and the only acpi_device on which _REG would get called for the EC Opregion before) is:
\_SB_.PC00.LPCB.LGEC.

Looking at the DSDT it seems that the H_EC is not used and is leftover from a copy/paste
from some reference design DSDT. Its _REG however does write to the EC before hitting the error
and I think that that write may be causing the issue...

The H_EC device does have an _STA method and looking closer the troublesome EREG method is
also called from _INI. So I guess that _STA is returning 0 causing _INI to not run and
that is the reason why we are not seeing the same EREG errors with kernel 6.9.6 where _REG is
only called for the EC opregion on \_SB_.PC00.LPCB.LGEC and not for the entire ACPI device
hierarchy as is done with >= 6.9.7 .

Maybe we should only call _REG for the EC opregion on present devices (and devices without
a _STA)?

Also note that both LGEC and H_EC use the same cmd + data ports.

I'll go and ask the reporter to retreive the status of both LGEC and H_EC and then see
from there.

Regards,

Hans