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

[Paul Menzel]

Dear Mario,


Thank you for your reply.

Am 15.02.2018 um 16:22 schrieb Mario.Limonciello@xxxxxxxx:
> > -----Original Message-----
> > From: Paul Menzel [mailto:pmenzel+linux-input@xxxxxxxxxxxxx]
> > Sent: Thursday, February 15, 2018 2:26 AM
> > To: Limonciello, Mario <Mario_Limonciello@xxxxxxxx>; Dmitry Torokhov
> > <dmitry.torokhov@xxxxxxxxx>
> > Cc: linux-input@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; it+linux-
> > input@xxxxxxxxxxxxx; linux@xxxxxxxxxxxxx
> > Subject: Re: i8042 AUX port [serio1] suspend takes a second on Dell XPS 13 9360

> > On 02/14/18 18:11, Mario.Limonciello@xxxxxxxx wrote:
> > > > -----Original Message-----
> > > > From: Paul Menzel [mailto:pmenzel+linux-input@xxxxxxxxxxxxx]
> > > > Sent: Wednesday, February 14, 2018 10:41 AM
> > > > To: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>
> > > > Cc: linux-input@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; it+linux-
> > > > input@xxxxxxxxxxxxx; Limonciello, Mario <Mario_Limonciello@xxxxxxxx>;
> > > > Thorsten Leemhuis <linux@xxxxxxxxxxxxx>
> > > > Subject: Re: i8042 AUX port [serio1] suspend takes a second on Dell XPS 13 9360
> >
> > > > 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 didnât work there
> > anymore. I was really sure, that I saw that problem once on the TUXEDO
> > device too, but must have been mistaken, thatâs 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.


Kind regards,

Paul