From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752000AbeBAVXv (ORCPT ); Thu, 1 Feb 2018 16:23:51 -0500 Received: from esa7.dell-outbound.iphmx.com ([68.232.153.96]:63734 "EHLO esa7.dell-outbound.iphmx.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751715AbeBAVXn (ORCPT ); Thu, 1 Feb 2018 16:23:43 -0500 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: =?us-ascii?q?A2FWAQCrhHNah8qZ6ERdGQEBAQEBAQEBA?= =?us-ascii?q?QEBAQcBAQEBAYQYgQUoCoNWmFKCAnyIF45KggIKhTsCGoIXVxUBAQEBAQEBAQI?= =?us-ascii?q?BAhABAQEKCwkIKC+COCKCSgEBAQQjBA1FDAQCAQgRBAEBAQICIwMCAgIfJQECA?= =?us-ascii?q?QUIAgQOBQgTigIDFaxngW06hzYNgyIBAQEBAQUBAQEBAQEBAQEfgQ+DWoIVgz+?= =?us-ascii?q?CeDaCa0QEgTMlHhYdgl2CRSAFo2U+kGiEfZQ6jjCJO4E8NYF0cIJ8gmWCEniLJ?= =?us-ascii?q?YEXAQEB?= X-IPAS-Result: =?us-ascii?q?A2FWAQCrhHNah8qZ6ERdGQEBAQEBAQEBAQEBAQcBAQEBAYQ?= =?us-ascii?q?YgQUoCoNWmFKCAnyIF45KggIKhTsCGoIXVxUBAQEBAQEBAQIBAhABAQEKCwkIK?= =?us-ascii?q?C+COCKCSgEBAQQjBA1FDAQCAQgRBAEBAQICIwMCAgIfJQECAQUIAgQOBQgTigI?= =?us-ascii?q?DFaxngW06hzYNgyIBAQEBAQUBAQEBAQEBAQEfgQ+DWoIVgz+CeDaCa0QEgTMlH?= =?us-ascii?q?hYdgl2CRSAFo2U+kGiEfZQ6jjCJO4E8NYF0cIJ8gmWCEniLJYEXAQEB?= From: X-LoopCount0: from 10.166.132.169 X-IronPort-AV: E=Sophos;i="5.46,444,1511848800"; d="scan'208";a="1209871001" X-DLP: DLP_GlobalPCIDSS To: CC: , , Subject: RE: Dell docking station & Dell Embedded Controller & PS/2 devices Thread-Topic: Dell docking station & Dell Embedded Controller & PS/2 devices Thread-Index: AQHTm5MKNYkzckAlZU27gJwgpYoerKOP74RAgACBNYD//50x8A== Date: Thu, 1 Feb 2018 21:23:40 +0000 Message-ID: References: <20180124104121.7g3zfay5smc5v2tc@pali> <20180201192945.wrsqjq7f5ejhqj6m@dtor-ws> In-Reply-To: Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.143.242.75] Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from base64 to 8bit by mail.home.local id w11LNsWq006997 > -----Original Message----- > From: Dmitry Torokhov [mailto:dmitry.torokhov@gmail.com] > Sent: Thursday, February 1, 2018 3:14 PM > To: Limonciello, Mario > Cc: Pali Rohár ; linux-input@vger.kernel.org; lkml kernel@vger.kernel.org> > Subject: Re: Dell docking station & Dell Embedded Controller & PS/2 devices > > 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 Rohár > >> 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 Rohár wrote: > >> > Hi Dmitry! > >> > > >> > I'm observing a problem with internal touchpad (handled by psmouse.ko) > >> > on Dell laptops connected to Dell E docking station. When I connect > >> > external PS/2 keyboard to docking station then internal laptop touchpad > >> > switch from multitouch absolute mode to relative bare PS/2 mode. > >> > > >> > And because ALPS driver in psmouse.ko is capable to process interleaved > >> > 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 back to > >> > multitouch mode. > >> > > >> > Mario told me that Dell Embedded Controller, which handle internal > >> > keyboard, internal touchpad and external PS/2 keyboard, automatically > >> > send RESET command to *all* those devices when external PS/2 keyboard is > >> > connected. Therefore this is reason why touchpad downgrade to to bare > >> > mode. And according to Mario, host system should issue vendor specific > >> > 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 not > >> 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 reconnect > >> 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 directly. > >> > > >> > 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. > >> > > >> > Dmitry, how to handle this situation to re-initialize psmouse.ko when > >> > external PS/2 device is connected to Dell E docking station? According > >> > to Mario, this is how Dell Embedded Controller is designed and suppose > >> > how OS should work with it. > >> > > >> > Manually rmmoding and modprobing for every docking/undocking laptop is > >> > not ideal solution. > >> > > >> > Could it be possible to use that Spurious ATKBD_RET_ACK from atkbd.c 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 adapter on > > the system. > > > > System EC is what will be sending any PS2 events. > > OK, it does not matter from the input layer POW, if they are PS/2 > events they should be coming from i8042. > > > > >> > >> /* Check if this is a new device announcement (0xAA 0x00) */ > >> if (unlikely(psmouse->packet[0] == PSMOUSE_RET_BAT && psmouse- > >> >pktcnt <= 2)) { > >> if (psmouse->pktcnt == 1) { > >> psmouse->last = jiffies; > >> goto out; > >> } > >> > >> if (psmouse->packet[1] == PSMOUSE_RET_ID || > >> (psmouse->protocol->type == PSMOUSE_HGPK && > >> psmouse->packet[1] == 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 i8042 > >> debug before trying to dock and capture the data stream from the mouse? > >> > > > > The system EC has reset PS2 devices (but AFAIK kernel won't have seen this > > communication). > > So what kind of communication does EC send when docking? It sounds it > is completely out of band from PS/2 connection. Yes it's out of band from PS/2 connection OS sees. However as Pali has mentioned this issue will happen even if already docked but you plug in PS/2 keyboard. It will probably be clearer to you what OS has seen from this when Pali shares the captured data stream.