From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hans de Goede Subject: Re: Regression since commit 92bac83 Date: Mon, 19 Oct 2015 10:08:35 +0200 Message-ID: <5624A503.7090609@redhat.com> References: <5624327B.7080906@lwfinger.net> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <5624327B.7080906@lwfinger.net> Sender: linux-kernel-owner@vger.kernel.org To: Larry Finger , Dmitry Torokhov , =?UTF-8?Q?Pali_Roh=c3=a1r?= , Masaki Ota Cc: linux-input@vger.kernel.org, LKML List-Id: linux-input@vger.kernel.org Hi, On 19-10-15 01:59, Larry Finger wrote: > Hi, > > I recently upgraded the kernel in a Dell Latitude D600 and found that the touchpad clicks failed. The problem was bisected to commit 92bac83dd79e60e65c475222e41a992a70434beb ("Input: alps - non interleaved V2 dualpoint has separate stick button bits"). The laptop has a combination touchpad and control stick. For this device, the following values are found: > > priv->protoversion is 0x200 (ALPS_PROTO_V2) > priv->flags is 0x6 (ALPS_DUALPOINT | ALPS_PASS) > > As a result, the new code added in this patch is executed, and left, right, and middle are updated. Once this code is introduced, a left click causes some event as it will wake a sleeping screen, but not select any windows or do anything useful. > > Please advise on what information would be needed to help debug this problem. Can you build a recent upstream kernel from source, and when building it comment out these lines in drivers/input/mouse/alps.c, around lines 2555 - 2556 if (dmi_name_in_vendors("Dell")) priv->flags |= ALPS_DELL; That should fix things, if that fixes things we need to rename the flag and move to a list of dmi-matched models (rather then vendor) where the new behavior introduced by the patch causing you problems is actually necessary. Step 1 is confirming that not setting the flag fixes things for you, if you can get back to us confirming that, then I'll whip up a patch to switch to model matching (which is not ideal, but seems to be necessary). Regards, Hans