From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dmitry Torokhov Subject: Re: ALPS v7 trackpad passthrough to Thinkpad trackpoint Date: Thu, 13 Aug 2015 15:48:39 -0700 Message-ID: <20150813224839.GC15693@dtor-ws> References: <20150807132639.GB21627@pali> <20150807141214.GD21627@pali> <20150813110317.GC20040@pali> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from mail-pd0-f177.google.com ([209.85.192.177]:35891 "EHLO mail-pd0-f177.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752135AbbHMWsp (ORCPT ); Thu, 13 Aug 2015 18:48:45 -0400 Received: by pdco4 with SMTP id o4so24494985pdc.3 for ; Thu, 13 Aug 2015 15:48:44 -0700 (PDT) Content-Disposition: inline In-Reply-To: <20150813110317.GC20040@pali> Sender: linux-input-owner@vger.kernel.org List-Id: linux-input@vger.kernel.org To: Pali =?iso-8859-1?Q?Roh=E1r?= Cc: Ari Entlich , linux-input@vger.kernel.org, Masaki Ota <012nexus@gmail.com>, Tommy Will , Yunkang Tang , Qiting Chen , Qiting Chen , vadim@cirque.com On Thu, Aug 13, 2015 at 01:03:17PM +0200, Pali Roh=E1r wrote: > On Friday 07 August 2015 12:35:33 Ari Entlich wrote: > > On Fri, Aug 7, 2015 at 10:12 AM, Pali Roh=E1r wrote: > > > For some old ALPS devices which use V1 and V2 protocols (with fla= g > > > ALPS_PASS) there is something like that. On that devices touchpad= is > > > behind trackpoint HW. But you cannot wait for data or poll for bo= th > > > devices at same time -- you need to choose if tou want to talk di= rectly > > > to touchpad (via passthrough mode) or just to trackpoint. I think > > > because of this limitation ALPS driver implement all logic in one > > > driver... > > > > > > Above was for old ALPS devices. New ALPS devices with V3 or V5 pr= otocols > > > have trackpoint behind touchpad, so normally OS communicate with > > > touchpad (and not with trackstick like before). But here touchpad= sends > > > data for both touchpad and trackstick events and so OS does not h= ave > > > normal access to "hidden" trackstick. > > > > > > There is a way "jump" into passthrough mode and talk directly to > > > trackpoint. But it is used only for configuring trackstick and cu= rrently > > > it is used to configure trackstick so it send data (via touchpad)= in > > > format which is supported by our ALPS driver. > > > > > > On the other hand, synaptics driver and devices support full > > > "encapsulation" or how can I call it of serio PS/2 device and in = this > > > case you can use full set of PS/2 commands directly with tracksti= ck > > > (behind synaptics touchpad). ALPS devices do not support somethin= g like > > > that. > >=20 > > It looks to me like the Synaptics passthrough is implemented primar= ily > > via the ability to write directly to the trackpoint. Events coming > > from the trackpoint are implemented similarly to the ALPS driver - = by > > redirecting trackpoint events to the second device which the driver > > creates for the trackpoint. > >=20 >=20 > No, passthrough for ALPS and Synaptics differ. Synaptics driver expor= ts > full serio PS/2 bus on which can be attached psmouse.ko driver with f= ull > mouse detection (or any other serio driver) and so there can be full > TPPS/2 trackpoint.c protocol driver. >=20 > ALPS allows us for *some* protocol version passthrough data directly = to > touchpad (or trackpoint) device. There is no support to exporting ful= l > serio bus with PS/2 access to it (like for Synaptics hardware). At least we do not know how to detect and activate it even if it exists= =2E Let's add some ALPS people to the thread: maybe they could share some details on accessing trackpoints behind the touchpads with us. Thanks. --=20 Dmitry -- To unsubscribe from this list: send the line "unsubscribe linux-input" = in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html