From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7CF7AC04AAF for ; Tue, 21 May 2019 13:38:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5CF1C208C3 for ; Tue, 21 May 2019 13:38:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728432AbfEUNin (ORCPT ); Tue, 21 May 2019 09:38:43 -0400 Received: from mx1.redhat.com ([209.132.183.28]:34242 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728393AbfEUNim (ORCPT ); Tue, 21 May 2019 09:38:42 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 70A553EDBF; Tue, 21 May 2019 13:38:42 +0000 (UTC) Received: from plouf.redhat.com (ovpn-116-49.ams2.redhat.com [10.36.116.49]) by smtp.corp.redhat.com (Postfix) with ESMTP id 0172E608C2; Tue, 21 May 2019 13:38:38 +0000 (UTC) From: Benjamin Tissoires To: Jiri Kosina Cc: linux-input@vger.kernel.org, linux-kernel@vger.kernel.org, Benjamin Tissoires , Breno Leitao Subject: [PATCH] HID: multitouch: handle faulty Elo touch device Date: Tue, 21 May 2019 15:38:31 +0200 Message-Id: <20190521133831.4436-1-benjamin.tissoires@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.39]); Tue, 21 May 2019 13:38:42 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Since kernel v5.0, one single win8 touchscreen device failed. And it turns out this is because it reports 2 InRange usage per touch. It's a first, and I *really* wonder how this was allowed by Microsoft in the first place. But IIRC, Breno told me this happened *after* a firmware upgrade... Anyway, better be safe for those crappy devices, and make sure we have a full slot before jumping to the next. This won't prevent all crappy devices to fail here, but at least we will have a safeguard as long as the contact ID and the X and Y coordinates are placed in the report after the grabage. Reported-and-tested-by: Breno Leitao Signed-off-by: Benjamin Tissoires --- drivers/hid/hid-multitouch.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/hid/hid-multitouch.c b/drivers/hid/hid-multitouch.c index ef635964cfe1..a344a3cf5398 100644 --- a/drivers/hid/hid-multitouch.c +++ b/drivers/hid/hid-multitouch.c @@ -642,6 +642,13 @@ static void mt_store_field(struct hid_device *hdev, if (*target != DEFAULT_TRUE && *target != DEFAULT_FALSE && *target != DEFAULT_ZERO) { + if (usage->contactid == DEFAULT_ZERO || + usage->x == DEFAULT_ZERO || + usage->y == DEFAULT_ZERO) { + hid_dbg(hdev, + "ignoring duplicate usage on incomplete"); + return; + } usage = mt_allocate_usage(hdev, application); if (!usage) return; -- 2.19.2