linux-kernel - Re: i8042 AUX port [serio1] suspend takes a second on Dell XPS 13 9360

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Message-ID: <a1ef8c9e-14e5-11c4-d7d5-52225027b6b1@molgen.mpg.de>
Date:   Thu, 9 Jul 2020 10:50:02 +0200
From:   Paul Menzel <pmenzel@...gen.mpg.de>
To:     Mario Limonciello <mario.limonciello@...l.com>,
        Dmitry Torokhov <dmitry.torokhov@...il.com>
Cc:     linux-input@...r.kernel.org, linux-kernel@...r.kernel.org,
        it+linux-input@...gen.mpg.de, linux@...mhuis.info
Subject: Re: i8042 AUX port [serio1] suspend takes a second on Dell XPS 13
 9360

Dear Dmitry, dear Mario,


Am 21.02.18 um 10:22 schrieb Paul Menzel:

> Am 15.02.2018 um 16:22 schrieb Mario.Limonciello@...l.com:
>>> -----Original Message-----
>>> From: Paul Menzel [mailto:pmenzel+linux-input@...gen.mpg.de]
>>> Sent: Thursday, February 15, 2018 2:26 AM
>>> On 02/14/18 18:11, Mario.Limonciello@...l.com wrote:
>>>>
>>>>> -----Original Message-----
>>>>> From: Paul Menzel [mailto:pmenzel+linux-input@...gen.mpg.de]
>>>>> Sent: Wednesday, February 14, 2018 10:41 AM
>>>
>>>>> On 01/30/18 19:07, Dmitry Torokhov wrote:
>>>>>> On Tue, Jan 30, 2018 at 09:52:45AM -0800, Dmitry Torokhov wrote:
>>>>>
>>>>>>> On Tue, Jan 30, 2018 at 06:36:34PM +0100, Paul Menzel wrote:
>>>>>
>>>>>>>> I do not know, when it started, but with Linux 4.14-rc8 and 4.15,
>>>>>>>> benchmarking suspend and resume time with `sleepgraph.py` [1][2], there is a
>>>>>>>> regression, that i8042 AUX port [serio1] suspend takes a second on Dell XPS
>>>>>>>> 13 9360 and TUXEDO Book 1406.
>>>>>>>
>>>>>>> It would be really helpful to know when the regression started.
>>>>>>
>>>>>> So the reason it takes longer is because the touchpad does not 
>>>>>> want to talk to us for some reason and we wait until commands time out:
>>>>>>
>>>>>> [   94.591636] calling  serio1+ @ 2299, parent: i8042
>>>>>> [   94.794292] psmouse serio1: Failed to disable mouse on isa0060/serio1
>>>>>> [   95.593303] call serio1+ returned 0 after 974280 usecs
>>>>>>
>>>>>> but it is not clear why it happens, I do not think we changed anything
>>>>>> in that path for a while, so it might be some other change affecting
>>>>>> things indirectly. I'm afraid you'll have to narrow the scope, and
>>>>>> ideally bisect.
>>>>
>>>> Please keep in mind the XPS 9360 has a touchpad that can operate in I2C
>>>> or PS2 modes.  It's connected to both buses and with the right initialization
>>>> sequence will come up in I2C mode.
>>>>
>>>> Assuming Paul M. has compiled and used hid-multitouch and i2c-hid the
>>>> touchpad should be operating in I2C mode.
>>>>
>>>> When this happens I expect that the touchpad shouldn't be responding
>>>> to PS2 commands.
>>>>
>>>> As a debugging tactic, you may consider to unload psmouse before
>>>> suspend and still see the touchpad operational.
>>>
>>> Thank you! Unloading *psmouse* with `sudo modprobe -r psmouse` indeed
>>> worked on the Dell XPS 13 9360, that means, the cursor is still 
>>> functioning.
>>>
>>>>> Thank you for your replies. First of all, it looks like *only* the Dell
>>>>> system is effected as I was unable to reproduce it on the TUXEDO Book
>>>>> 1406. I have to verify that by finding old log files.
>>>>
>>>> Does this other laptop you are drawing a comparison to also have a
>>>> touchpad that can operate in multiple modes?
>>>>
>>>> To make an accurate comparison you should determine what mode it's in.
>>>
>>> Yeah, removing the module *psmouse*, the cursor didn’t work there
>>> anymore. I was really sure, that I saw that problem once on the TUXEDO
>>> device too, but must have been mistaken, that’s why I corrected it.
>>> Sorry for the misunderstanding.
>>>
>>> So, why does *psmouse* get loaded on the Dell XPS 13 9360 since at least
>>> Linux 4.13? Or where the modules added causing the touchpad to operate
>>> in I2C mode, which causes PS2 to stop to work?
>>
>> It was like that before this laptop even launched to the market.
>> It's been like that since way before 4.13.  I want to say maybe 
>> 3.13ish is when
>> I2C mode would come up instead.
> 
> Indeed, analyzing the behavior on the current 8th generation Dell XPS 13 
> 93*7*0 with the shipped Ubuntu with Linux 4.4.0-112-generic, the same 
> delay is visible.
> 
>> The order of events goes something like this:
>> 1) Touchpad is initially in PS2 mode
>> 2) psmouse loads
>> 3) It reports that it may be supportable by a different bus
>> 4) The sequence to switch to I2C mode happens
>> 5) i2c-hid and hid-multitouch get loaded
>> 6) psmouse is no longer functional
>>
>> Dmitry is there a way that we can connect the two events?  When 
>> i2c-hid finds
>> the touchpad notify psmouse to unload or at least stop trying to 
>> access it to prevent
>> the problem Paul is talking about with suspend?
> 
> That would be great. Please tell me, if there is a bug tracker, where 
> this issue should reported to to track it.

The issue is still present with Linux 5.8-rc4. Does Mario’s plan sound 
feasible?


Kind regards,

Paul