Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030324AbbDWQtY (ORCPT ); Thu, 23 Apr 2015 12:49:24 -0400 Received: from mail-la0-f46.google.com ([209.85.215.46]:35509 "EHLO mail-la0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S966614AbbDWQtU (ORCPT ); Thu, 23 Apr 2015 12:49:20 -0400 MIME-Version: 1.0 In-Reply-To: References: <1427741655-4142-1-git-send-email-benjamin.tissoires@redhat.com> <20150406163349.GD36770@dtor-ws> Date: Thu, 23 Apr 2015 09:49:18 -0700 Message-ID: Subject: Re: [PATCH v2] Input - mt: Fix input_mt_get_slot_by_key From: Dmitry Torokhov To: Jiri Kosina Cc: Benjamin Tissoires , Henrik Rydberg , "linux-input@vger.kernel.org" , lkml Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1700 Lines: 41 On Tue, Apr 7, 2015 at 6:17 AM, Jiri Kosina wrote: > On Mon, 6 Apr 2015, Dmitry Torokhov wrote: > >> > With https://git.kernel.org/cgit/linux/kernel/git/jikos/hid.git/commit/?h=for-4.1/wacom&id=9a1c001298fd567c0f0776ab54ab9965eeb9019f >> > in Jiri's tree, scheduled for 4.1, this patch should not break any existing >> > driver. I'd like us to stage it somewhere so that it doesn't get forgotten. >> > >> > Henrik's previous concerns were that input_mt_sync_frame() may not be called >> > by a driver using input_mt_get_slot_by_key(), and now, no driver should be in >> > this case. >> >> I'm OK with it going through Juri's tree. >> >> Acked-by: Dmitry Torokhov > > Perfect, thanks. I have now queued it in for-4.1/upstream. Actually, thinking about it some more, I do not think this patch is needed. It should be perfectly fine to replace the tracking ID in a slot to denote a new contact. From Documentation/input/multi-touch-protocol.txt "Creation, replacement and destruction of contacts is achieved by modifying the ABS_MT_TRACKING_ID of the associated slot. A non-negative tracking id is interpreted as a contact, and the value -1 denotes an unused slot. A tracking id not previously present is considered new, and a tracking id no longer present is considered removed." If some userspace is confused with missing -1 tracking ID for that slot, that userspace should be fixed. Thanks. -- Dmitry -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/