From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752540AbeBDUIH (ORCPT ); Sun, 4 Feb 2018 15:08:07 -0500 Received: from mail-wm0-f45.google.com ([74.125.82.45]:38073 "EHLO mail-wm0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751797AbeBDUIB (ORCPT ); Sun, 4 Feb 2018 15:08:01 -0500 X-Google-Smtp-Source: AH8x225kvLrMuN9UcC4pz14v2qRdLFBpgo61t8TnpCs0cNDxXSKOm9SPI9+fdzMn0ykJ3UHbh4EI9A== Date: Sun, 4 Feb 2018 21:07:57 +0100 From: Pali =?utf-8?B?Um9ow6Fy?= To: Mario.Limonciello@dell.com Cc: dmitry.torokhov@gmail.com, linux-input@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: Dell docking station & Dell Embedded Controller & PS/2 devices Message-ID: <20180204200757.kt5awlysvbbthlep@pali> References: <20180124104121.7g3zfay5smc5v2tc@pali> <20180201192945.wrsqjq7f5ejhqj6m@dtor-ws>

MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="t7ychuym3ussoodl" Content-Disposition: inline In-Reply-To: User-Agent: NeoMutt/20170113 (1.7.2) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --t7ychuym3ussoodl Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Thursday 01 February 2018 21:23:40 Mario.Limonciello@dell.com wrote: > > -----Original Message----- > > From: Dmitry Torokhov [mailto:dmitry.torokhov@gmail.com] > > Sent: Thursday, February 1, 2018 3:14 PM > > To: Limonciello, Mario > > Cc: Pali Roh=C3=A1r ; linux-input@vger.kernel.org= ; lkml > kernel@vger.kernel.org> > > Subject: Re: Dell docking station & Dell Embedded Controller & PS/2 dev= ices > >=20 > > On Thu, Feb 1, 2018 at 11:35 AM, wrote: > > > > > > > > >> -----Original Message----- > > >> From: Dmitry Torokhov [mailto:dmitry.torokhov@gmail.com] > > >> Sent: Thursday, February 1, 2018 1:30 PM > > >> To: Pali Roh=C3=A1r > > >> Cc: Limonciello, Mario ; linux- > > >> input@vger.kernel.org; linux-kernel@vger.kernel.org > > >> Subject: Re: Dell docking station & Dell Embedded Controller & PS/2 = devices > > >> > > >> Hi Pali, > > >> > > >> On Wed, Jan 24, 2018 at 11:41:21AM +0100, Pali Roh=C3=A1r wrote: > > >> > Hi Dmitry! > > >> > > > >> > I'm observing a problem with internal touchpad (handled by psmouse= =2Eko) > > >> > on Dell laptops connected to Dell E docking station. When I connect > > >> > external PS/2 keyboard to docking station then internal laptop tou= chpad > > >> > switch from multitouch absolute mode to relative bare PS/2 mode. > > >> > > > >> > And because ALPS driver in psmouse.ko is capable to process interl= eaved > > >> > bare 3-byte PS/2 packets with 6-byte ALPS packets (which handles > > >> > trackstick data on some ALPS models), ALPS driver does not show any > > >> > message about this "downgrade" from multitouch to bare mode. And > > >> > continue working in bare mode. > > >> > > > >> > When I rmmod psmouse and modprobe it again, then touchpad switch b= ack to > > >> > multitouch mode. > > >> > > > >> > Mario told me that Dell Embedded Controller, which handle internal > > >> > keyboard, internal touchpad and external PS/2 keyboard, automatica= lly > > >> > send RESET command to *all* those devices when external PS/2 keybo= ard is > > >> > connected. Therefore this is reason why touchpad downgrade to to b= are > > >> > mode. And according to Mario, host system should issue vendor spec= ific > > >> > PS/2 commands to re-initialize all PS/2 devices when this situation > > >> > happen. Mario also told me that Windows is doing this action. > > >> > > >> Yeah, I remember fun with Inspiron 8100 - when you dock it it woudl > > >> silently switch Synaptics touchpad into standard mode and it would n= ot > > >> come back as Synaptics until you disconnect. And there was no > > >> notification to the kernel as far as I could tell. > > >> > > >> It could be that we need to monitor dock events and then kick reconn= ect > > >> of serio port, either from userspace via udev (I think that would be > > >> preferred), or in kernel. > > >> > > >> > > > >> > Every time when I connect external PS/2 keyboard to dock I see this > > >> > message in dmesg: > > >> > > > >> > Spurious ACK... Some program might be trying to access hardware di= rectly. > > >> > > > >> > 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 c= onnect > > >> > external PS/2 mouse to dock. > > >> > > > >> > Dmitry, how to handle this situation to re-initialize psmouse.ko w= hen > > >> > external PS/2 device is connected to Dell E docking station? Accor= ding > > >> > to Mario, this is how Dell Embedded Controller is designed and sup= pose > > >> > how OS should work with it. > > >> > > > >> > Manually rmmoding and modprobing for every docking/undocking lapto= p is > > >> > not ideal solution. > > >> > > > >> > Could it be possible to use that Spurious ATKBD_RET_ACK from atkbd= =2Ec be > > >> > handled on Dell systems (probably via DMI) as an event to reset and > > >> > reinitialize all PS/2 devices? > > >> > > >> So we need to figure out what exactly we are getting from the docking > > >> station in this case. We do try to handle the new device 0xaa 0x00 > > >> announcements: > > > > > > Docking station itself won't have sent any events. The PS2 ports in = it > > > are electrically wired to the external PS2 pins in the docking adapte= r on > > > the system. > > > > > > System EC is what will be sending any PS2 events. > >=20 > > OK, it does not matter from the input layer POW, if they are PS/2 > > events they should be coming from i8042. Dell EC sends reset to touchpad, not to kernel. > > > > > >> > > >> /* Check if this is a new device announcement (0xAA 0x00) */ > > >> if (unlikely(psmouse->packet[0] =3D=3D PSMOUSE_RET_BAT && psmo= use- > > >> >pktcnt <=3D 2)) { > > >> if (psmouse->pktcnt =3D=3D 1) { > > >> psmouse->last =3D jiffies; > > >> goto out; > > >> } > > >> > > >> 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; > > >> } > > >> > > >> ... > > >> > > >> I am not sure where the "spurious ACK comes from". Can you enable i8= 042 > > >> debug before trying to dock and capture the data stream from the mou= se? > > >> > > > > > > The system EC has reset PS2 devices (but AFAIK kernel won't have seen= this > > > communication). > >=20 > > So what kind of communication does EC send when docking? It sounds it > > is completely out of band from PS/2 connection. >=20 > Yes it's out of band from PS/2 connection OS sees. However as Pali has= =20 > mentioned this issue will happen even if already docked but you plug in > PS/2 keyboard. >=20 > It will probably be clearer to you what OS has seen from this when Pali > shares the captured data stream. Currently I'm not near my docking station, so cannot do testing. But in logs I can dig these lines which appeared every time after putting notebook into dock (which has PS/2 keyboard connected): kernel: [20127.033965] atkbd serio0: Spurious ACK on isa0060/serio0. Some p= rogram might be trying to access hardware directly. kernel: [20127.076030] acpi PNP0401:00: Already enumerated kernel: [20127.083088] acpi PNP0501:00: Still not present kernel: [20127.087042] acpi device:41: Cannot transition to power state D3h= ot for parent in (unknown) And sometimes after 1-5s I see Spurious event again: kernel: [20128.325569] atkbd serio0: Spurious ACK on isa0060/serio0. Some p= rogram might be trying to access hardware directly. --=20 Pali Roh=C3=A1r pali.rohar@gmail.com --t7ychuym3ussoodl Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iF0EABECAB0WIQS4VrIQdKium2krgIWL8Mk9A+RDUgUCWndoGQAKCRCL8Mk9A+RD UgFlAJ4n0AZpq2JpBeSawLnaKepLMK2NtwCgufXAVOhQd83obQ2+oPixXkC233o= =z8NN -----END PGP SIGNATURE----- --t7ychuym3ussoodl--