Re: PROBLEM: asus_nb_wmi sends KEY_BRIGHTNESSDOWN on pressing CAPS Lock and PrntScrn on Zenbook S 13 UX5304VA

From: Hans de Goede
Date: Sun Oct 01 2023 - 09:46:29 EST


Hi James,

On 10/1/23 10:46, James John wrote:
> Hello Han,
>
> Thank you very much for this detailed steps. I was able to reproduce this with "evtest" and everything went okay.
>
> After editing /lib/udev/hwdb.d/60-keyboarrd.hwdb as you specified, the problem has been fixed, which I believe should revert on reboot?

No this will fix it until /lib/udev/hwdb.d/60-keyboarrd.hwdb gets overwritten by your
package-manager the next time the systemd packages get updated.

> This is the content of /sys/class/dmi/id/modalias
>
> dmi:bvnAmericanMegatrendsInternational,LLC.:bvrUX5304VA.304:bd05/16/2023:br5.27:svnASUSTeKCOMPUTERINC.:pnZenbookS13UX5304VA_UX5304VA:pvr1.0:rvnASUSTeKCOMPUTERINC.:rnUX5304VA:rvr1.0:cvnASUSTeKCOMPUTERINC.:ct10:cvr1.0:sku:

Thanks.

Looking at:
https://bbs.archlinux.org/viewtopic.php?pid=2123716

I see that at least one other model Asus laptop is affected too. So rather then
adding a more specific hwdb rule for your model I would like to try and find
the root cause of these 0x20 event code events when pressing capslock
on your laptop.

> Yes, I built my kernel. I wish I could parse this and write a proper quirk.

Good, I've written a small kernel patch to get to the bottom of this (attached)
can you please build a kernel with this. Then boot into this kernel and
then run dmesg -w

When you now press capslock you should see log lines show up which contain
"raw event code 0x..."

Please let me know what these lines show when pressing capslock.

Please also let me know what these lines show when pressing other
hotkeys which are handled by asus-nb-wmi (you can re-run "sudo evtest"
to check which keys that are).

I think the issue might be that the asus-wmi code is filtering out
the higher bits of the value, which causes some new events to
get mapped as just 0x20 instead of some-higher-bits + 0x20.

Also I'm wondering if everything else works as it should,
e.g. does changing the brightness with the brightness hotkeys
still work after setting up the hwdb filtering ?

And does the lid-switch (suspend the machine when the lid is closed)
work ?


> Also, I don't know if this is related; the hotkeys should be enabled by default. Fn key should be for Function keys. But in the current state, it is reversed.

This is laptop models specific and not really controlled by Linux,
sometimes you can change the default in the BIOS. Or sometimes you
can change the default by pressing Fn + Esc.

Regards,

Hans




> On 01/10/2023 09:28, Hans de Goede wrote:
>> Hi James,
>>
>> On 10/1/23 10:11, James John wrote:
>>> Hello,
>>>
>>> First of all, thank you very much for the work you do with maintaining these drivers and supporting systems. It is not an easy one.
>>>
>>> I have debugged this bug down to the asus_nb_wmi module. When I disable this module, the problem goes away, but then other hotkeys are not recognized. Attached is a debug event from libinput, where I pressed the capslock twice
>>>
>>> I have tried to dabble around with asus-nb-wmi.c codes to see if I could fix it by luck, by adding UX5304VA to `static const struct dmi_system_id asus_quirks[]` but to no avail. And I have a very little knowledge of what "quirks" are.
>>>
>>> I have attached some information regarding my hardware and kernel. I will be available to provide any more information that might be needed to resolve this.
>>>
>>> A related open thread: https://bbs.archlinux.org/viewtopic.php?pid=2123716
>> First of all lets confirm that the KEY_BRIGHTNESSDOWN events are really coming from asus_nb_wmi.
>>
>> Please install evtest and then run "sudo evtest" and then select the "Asus WMI hotkeys" device
>> by typing its number followed by enter.
>>
>> After this reproduce the bug and see if the log shows KEY_BRIGHTNESSDOWN.
>>
>> Since you said you tried playing around with the quirks, I assume you can build
>> your own kernel, please let me know if that is wrong.
>>
>> If this confirms the KEY_BRIGHTNESSDOWN events are coming from the "Asus WMI hotkeys" device,
>> then please edit /lib/udev/hwdb.d/60-keyboard.hwdb
>>
>> And search for "Asus WMI hotkeys", this should find this section:
>>
>> evdev:name:Asus WMI hotkeys:dmi:bvn*:bvr*:bd*:svnASUS*:pn*:*
>> evdev:name:Eee PC WMI hotkeys:dmi:bvn*:bvr*:bd*:svnASUS*:pn*:*
>> evdev:name:Asus Laptop extra buttons:dmi:bvn*:bvr*:bd*:svnASUS*:pn*:*
>>   KEYBOARD_KEY_6b=f21                                    # Touchpad Toggle
>>   KEYBOARD_KEY_7c=f20                                    # Remap micmute to f20
>>
>> Change this to:
>>
>> evdev:name:Asus WMI hotkeys:dmi:bvn*:bvr*:bd*:svnASUS*:pn*:*
>> evdev:name:Eee PC WMI hotkeys:dmi:bvn*:bvr*:bd*:svnASUS*:pn*:*
>> evdev:name:Asus Laptop extra buttons:dmi:bvn*:bvr*:bd*:svnASUS*:pn*:*
>>   KEYBOARD_KEY_6b=f21                                    # Touchpad Toggle
>>   KEYBOARD_KEY_7c=f20                                    # Remap micmute to f20
>>   KEYBOARD_KEY_20=unknown
>>
>> And then run "sudo udevadm hwdb --update" followed by "sudo udevadm trigger",
>> that should filter out the spurious keypresses.
>>
>> If that helps, please run:
>>
>> cat /sys/class/dmi/id/modalias
>>
>> So that a proper DMI based quirk to only to the filtering on your model
>> can be written.
>>
>> Regards,
>>
>> Hans
>>
> From d392204b9d909e45fc74be47ccfae7132ec298f0 Mon Sep 17 00:00:00 2001
From: Hans de Goede <hdegoede@xxxxxxxxxx>
Date: Sun, 1 Oct 2023 15:27:17 +0200
Subject: [PATCH] platform/x86: asus-wmi: event code debug patch

Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
---
drivers/platform/x86/asus-wmi.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/platform/x86/asus-wmi.c b/drivers/platform/x86/asus-wmi.c
index 928fc74e79b4..e1727b80a898 100644
--- a/drivers/platform/x86/asus-wmi.c
+++ b/drivers/platform/x86/asus-wmi.c
@@ -3937,9 +3937,10 @@ static int asus_wmi_get_event_code(u32 value)

obj = (union acpi_object *)response.pointer;

- if (obj && obj->type == ACPI_TYPE_INTEGER)
+ if (obj && obj->type == ACPI_TYPE_INTEGER) {
+ pr_info("raw event code 0x%llx\n", obj->integer.value);
code = (int)(obj->integer.value & WMI_EVENT_MASK);
- else
+ } else
code = -EIO;

kfree(obj);
--
2.41.0