From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dmitry Torokhov Subject: Re: [PATCH v3] synaptics: Add min/max quirk for ThinkPad T431s, L440, L540, S1 Yoga and X1 Date: Sat, 19 Apr 2014 22:32:29 -0700 Message-ID: <20140420053229.GC12454@core.coreip.homeip.net> References: <1397734903-26088-1-git-send-email-hdegoede@redhat.com> <1397734903-26088-2-git-send-email-hdegoede@redhat.com> <20140417153500.GA17495@core.coreip.homeip.net> <534FF8E6.7060305@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <534FF8E6.7060305@redhat.com> Sender: stable-owner@vger.kernel.org To: Hans de Goede Cc: Benjamin Tissoires , Peter Hutterer , linux-input@vger.kernel.org, stable@vger.kernel.org, Benjamin Tissoires List-Id: linux-input@vger.kernel.org On Thu, Apr 17, 2014 at 05:53:10PM +0200, Hans de Goede wrote: > Hi, > > On 04/17/2014 05:35 PM, Dmitry Torokhov wrote: > > Hi Hans, > > > > On Thu, Apr 17, 2014 at 01:41:43PM +0200, Hans de Goede wrote: > >> We expect that all the Haswell series will need such quirks, sigh. > > > > Given this statement do we really want this to be handled in kernel? > > I know this answer won't make you happy, but short term: Yes, we are > getting many many bugreports about this, ie: > > https://bugzilla.redhat.com/show_bug.cgi?id=1060885 > https://bugzilla.redhat.com/show_bug.cgi?id=1068716 > https://bugzilla.redhat.com/show_bug.cgi?id=1085582 > https://bugzilla.redhat.com/show_bug.cgi?id=1085697 > https://bugzilla.redhat.com/show_bug.cgi?id=1086227 > > And by extending the *already present* quirk table we can get this > issue resolved quickly, and also resolve it for people running > older kernels through the various stable series. > > > Maybe we simply want udev to fix up the limits with EVIOSABS(), > > Ah, I did not know that it is possible to fixup the min/max values > from user space, that is good to know. > > > similarly to how we adjust keymaps for laptops? > > We're currently looking into various ways to make this less painful, > specifically for most laptops the problem seems to be the min value > and not the max value. And the troublesome min value is the synaptics > driver default, not the one we get from the firmware. The problem is > we never ask the firmware because even though it has the "I can report > min values" capability bit, its "maximum understood request" number > is too low, so one of our 2 checks for getting the min value is > failing. If we remove that check some models do give us a proper > range (but not all, ie the T440s is still wrong). > > We're currently trying to figure out if it will be safe for all models > to remove the "maximum understood request" number check. That should ie > remove the quirk for the x240 and possible others. > > An other option to make this better is to switch the quirks to using > pnp-ids, ie the L440 and L540 share the same pnp-id. Once you've > merged the firmware_id patches I can take a shot at simplifying the > quirk table that way. Downside is that we then probably need to > put the firmware_id patches in the various stable kernels. > > Note that even if we end up moving this to userspace, then we still > need the firmware_id, because I believe any userspace solution should > be using pnp-ids too. > > TL;DR: It is complicated and for now we would like to continue with > the quirks as we've done sofar. We are aware that this is undesirable > from a maintenance pov and are looking into making this better. OK, fair enough. I applied the patch. Thanks. -- Dmitry