From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pali =?utf-8?B?Um9ow6Fy?= Subject: Re: Dell docking station & Dell Embedded Controller & PS/2 devices Date: Mon, 7 May 2018 21:58:55 +0200 Message-ID: <20180507195855.b347ppcmg4hnzqwf@pali> References: <20180124104121.7g3zfay5smc5v2tc@pali> <20180201192945.wrsqjq7f5ejhqj6m@dtor-ws> <20180506134733.zttaitnf6ej4tith@pali> <20180507084431.r2dipv32wt3vbx3k@pali> <20180507193306.GA31301@dtor-ws> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="35576izvvjplpdef" Return-path: Content-Disposition: inline In-Reply-To: <20180507193306.GA31301@dtor-ws> Sender: linux-kernel-owner@vger.kernel.org To: Dmitry Torokhov Cc: Mario.Limonciello@dell.com, linux-input@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-input@vger.kernel.org --35576izvvjplpdef Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Monday 07 May 2018 12:33:06 Dmitry Torokhov wrote: > On Mon, May 07, 2018 at 10:44:31AM +0200, Pali Roh=C3=A1r wrote: > > On Sunday 06 May 2018 15:47:33 Pali Roh=C3=A1r wrote: > > > On Thursday 01 February 2018 11:29:45 Dmitry Torokhov wrote: > > > > Hi Pali, > > > >=20 > > > > On Wed, Jan 24, 2018 at 11:41:21AM +0100, Pali Roh=C3=A1r wrote: > > > > > Hi Dmitry! > > > > >=20 > > > > > I'm observing a problem with internal touchpad (handled by psmous= e.ko) > > > > > on Dell laptops connected to Dell E docking station. When I conne= ct > > > > > external PS/2 keyboard to docking station then internal laptop to= uchpad > > > > > switch from multitouch absolute mode to relative bare PS/2 mode. > > > > >=20 > > > > > And because ALPS driver in psmouse.ko is capable to process inter= leaved > > > > > bare 3-byte PS/2 packets with 6-byte ALPS packets (which handles > > > > > trackstick data on some ALPS models), ALPS driver does not show a= ny > > > > > message about this "downgrade" from multitouch to bare mode. And > > > > > continue working in bare mode. > > > > >=20 > > > > > When I rmmod psmouse and modprobe it again, then touchpad switch = back to > > > > > multitouch mode. > > > > >=20 > > > > > Mario told me that Dell Embedded Controller, which handle internal > > > > > keyboard, internal touchpad and external PS/2 keyboard, automatic= ally > > > > > send RESET command to *all* those devices when external PS/2 keyb= oard is > > > > > connected. Therefore this is reason why touchpad downgrade to to = bare > > > > > mode. And according to Mario, host system should issue vendor spe= cific > > > > > PS/2 commands to re-initialize all PS/2 devices when this situati= on > > > > > happen. Mario also told me that Windows is doing this action. > > > >=20 > > > > Yeah, I remember fun with Inspiron 8100 - when you dock it it woudl > > > > silently switch Synaptics touchpad into standard mode and it would = not > > > > come back as Synaptics until you disconnect. And there was no > > > > notification to the kernel as far as I could tell. > > > >=20 > > > > It could be that we need to monitor dock events and then kick recon= nect > > > > of serio port, either from userspace via udev (I think that would be > > > > preferred), or in kernel. > > > >=20 > > > > >=20 > > > > > Every time when I connect external PS/2 keyboard to dock I see th= is > > > > > message in dmesg: > > > > >=20 > > > > > Spurious ACK... Some program might be trying to access hardware d= irectly. > > > > >=20 > > > > > I see it also every time when I dock laptop into docking station = (to > > > > > which is keyboard already connected). And it happens also when I = connect > > > > > external PS/2 mouse to dock. > > > > >=20 > > > > > Dmitry, how to handle this situation to re-initialize psmouse.ko = when > > > > > external PS/2 device is connected to Dell E docking station? Acco= rding > > > > > to Mario, this is how Dell Embedded Controller is designed and su= ppose > > > > > how OS should work with it. > > > > >=20 > > > > > Manually rmmoding and modprobing for every docking/undocking lapt= op is > > > > > not ideal solution. > > > > >=20 > > > > > Could it be possible to use that Spurious ATKBD_RET_ACK from atkb= d.c be > > > > > handled on Dell systems (probably via DMI) as an event to reset a= nd > > > > > reinitialize all PS/2 devices? > > > >=20 > > > > So we need to figure out what exactly we are getting from the docki= ng > > > > station in this case. We do try to handle the new device 0xaa 0x00 > > > > announcements: > > > >=20 > > > > /* Check if this is a new device announcement (0xAA 0x00) */ > > > > if (unlikely(psmouse->packet[0] =3D=3D PSMOUSE_RET_BAT && psmouse-= >pktcnt <=3D 2)) { > > > > if (psmouse->pktcnt =3D=3D 1) { > > > > psmouse->last =3D jiffies; > > > > goto out; > > > > } > > > >=20 > > > > if (psmouse->packet[1] =3D=3D PSMOUSE_RET_ID || > > > > (psmouse->protocol->type =3D=3D PSMOUSE_HGPK && > > > > psmouse->packet[1] =3D=3D PSMOUSE_RET_BAT)) { > > > > __psmouse_set_state(psmouse, PSMOUSE_IGNORE); > > > > serio_reconnect(serio); > > > > goto out; > > > > } > > > >=20 > > > > ... > > > >=20 > > > > I am not sure where the "spurious ACK comes from". Can you enable i= 8042 > > > > debug before trying to dock and capture the data stream from the mo= use? > > > >=20 > > > > Thanks. > > > >=20 > > >=20 > > > Hi Dmitry! > > >=20 > > > I enabled unmask_kbd_data and debug and here is output from dmesg. > > >=20 > > > echo Y >=C2=A0/sys/module/i8042/parameters/debug > > > echo Y > /sys/module/i8042/parameters/unmask_kbd_data > > >=20 > > > PS/2 keyboard is already connected in dock and laptop was just docked: > > >=20 > > > [25461.552314] i8042: [6365474] fa <- i8042 (interrupt, 0, 1) > > > [25461.552319] atkbd serio0: Spurious ACK on isa0060/serio0. Some pro= gram might be trying to access hardware directly. > > > [25462.707296] i8042: [6365763] ed -> i8042 (kbd-data) > > > [25462.851289] i8042: [6365799] fa <- i8042 (interrupt, 0, 1) > > > [25462.851303] i8042: [6365799] 00 -> i8042 (kbd-data) > > > [25462.858437] i8042: [6365801] fa <- i8042 (interrupt, 0, 1) > > > [25462.869512] i8042: [6365804] fa <- i8042 (interrupt, 0, 1) > > > [25462.869517] atkbd serio0: Spurious ACK on isa0060/serio0. Some pro= gram might be trying to access hardware directly. > > > [25463.670515] i8042: [6366004] ed -> i8042 (kbd-data) > > > [25463.670647] i8042: [6366004] fa <- i8042 (interrupt, 0, 1) > > > [25463.670655] i8042: [6366004] 02 -> i8042 (kbd-data) > > > [25463.676769] i8042: [6366005] fa <- i8042 (interrupt, 0, 1) > > >=20 > > >=20 > > > Laptop is docked and PS/2 keyboard was just connected: > > >=20 > > > [26571.014368] i8042: [6642848] fa <- i8042 (interrupt, 0, 1) > > > [26571.014380] atkbd serio0: Spurious ACK on isa0060/serio0. Some pro= gram might be trying to access hardware directly. > > >=20 > > >=20 > > > In both cases there is no events from touchpad, only from keyboard. So > > > Dell EC silently reset PS/2 touchpad when PS/2 keyboard is attached. > > >=20 > > > So I think we should capture 0xFA and on Dell machines we should > > > reinitialize PS/2 drivers. As there is really nothing more then 0xFA. > >=20 > > Info about PS/2 mouse: > >=20 > > In case I have laptop already docked and just connect PS/2 mouse there > > is absolutely no i8042 event. > >=20 > > To check that mouse is worked I clicked button and then in dmesg > > appeared: > >=20 > > [ 3945.481403] i8042: [986322] 09 <- i8042 (interrupt, 1, 12) > > [ 3945.482486] i8042: [986323] 00 <- i8042 (interrupt, 1, 12) > > [ 3945.483667] i8042: [986323] 00 <- i8042 (interrupt, 1, 12) > > [ 3945.483917] input: PS/2 ALPS Mouse as /devices/platform/i8042/serio1= /input/input36 > > [ 3945.594926] i8042: [986351] 08 <- i8042 (interrupt, 1, 12) > > [ 3945.596062] i8042: [986351] 00 <- i8042 (interrupt, 1, 12) > > [ 3945.597203] i8042: [986351] 00 <- i8042 (interrupt, 1, 12) > >=20 > > So we have no way to detect when external PS/2 mouse was connected to > > dock. But ALPS driver can deal with it and process these mouse events. > >=20 > > And when I have already connected PS/2 mouse to the dock and I'm just > > putting laptop into dock, then I get following events: > >=20 > > [ 4336.481381] i8042: [1084079] fa <- i8042 (interrupt, 0, 1) > > [ 4336.481388] atkbd serio0: Spurious ACK on isa0060/serio0. Some progr= am might be trying to access hardware directly. > > [ 4337.653275] i8042: [1084372] ed -> i8042 (kbd-data) >=20 > I wonder where this "set leds" command is coming from and where is the > parameter... Can you add some more tracing? And maybe boot with > libps2.dyndbg=3D+pf >=20 > > [ 4337.949198] i8042: [1084446] fa <- i8042 (interrupt, 0, 1) > > [ 4337.949202] atkbd serio0: Spurious ACK on isa0060/serio0. Some progr= am might be trying to access hardware directly. > > [ 4338.623167] i8042: [1084615] ed -> i8042 (kbd-data) > >=20 > > So again, no event from mouse, just from keyboard. > >=20 > > Note that in these tests I have disconnected my PS/2 keyboard from > > dock. >=20 > So I guess you could write a platform driver that would install i8042 > filter on Dell laptops/portables, monitor keyboard data stream and kick > of rescans on serio ports. Ok. dell-laptop.ko already installs i8042 filter, so it could be extended. How can such dell-laptop.ko driver instruct serio0/1 devices to reinitialize bound drivers (atk and psmouse, probably other)? > The problem is filter gets "serio" so you do > not really know whether ACK is spurious or not. It is possible to extend i8042/serio driver to provide information via i8042 filter callback if ACK is spurious or not? > And I would really > prefer keeping this crap out of atkbd proper... And all of this is racy > as hell. What happens if we get keyboard reconnected as we reinitialize > it? Do not know, such race conditions are hard to test as you need correct timing. And doing connecting/disconnecting PS/2 cable from dock together with laptop docking/undocking cannot be done reliable for less then 5s (need to press two buttons, take/unplug laptop + reconnecting PS/2 slot) so hard to simulate race condition. Plus we do not know what is that Dell EC doing with PS/2 data... > Mario, how does Windows driver know when it should send "vendor" > commands to reinitialize peripherals? >=20 > Thanks. >=20 --=20 Pali Roh=C3=A1r pali.rohar@gmail.com --35576izvvjplpdef Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iF0EABECAB0WIQS4VrIQdKium2krgIWL8Mk9A+RDUgUCWvCv/QAKCRCL8Mk9A+RD UpL7AJwMjuihDww5wG6cxR9O4PmO2VqLMQCcC3j2V1O18O9KuO41NmnTkkGWFN4= =may6 -----END PGP SIGNATURE----- --35576izvvjplpdef--