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=-0.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no 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 1F2DFC54E4B for ; Tue, 12 May 2020 05:19:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0380020733 for ; Tue, 12 May 2020 05:19:33 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=who-t.net header.i=@who-t.net header.b="XsxHUTRm"; dkim=pass (2048-bit key) header.d=messagingengine.com header.i=@messagingengine.com header.b="bMXXBdCU" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725946AbgELFTc (ORCPT ); Tue, 12 May 2020 01:19:32 -0400 Received: from wout5-smtp.messagingengine.com ([64.147.123.21]:43671 "EHLO wout5-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725933AbgELFTc (ORCPT ); Tue, 12 May 2020 01:19:32 -0400 Received: from compute7.internal (compute7.nyi.internal [10.202.2.47]) by mailout.west.internal (Postfix) with ESMTP id 413D16C3; Tue, 12 May 2020 01:19:31 -0400 (EDT) Received: from mailfrontend1 ([10.202.2.162]) by compute7.internal (MEProxy); Tue, 12 May 2020 01:19:31 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=who-t.net; h= date:from:to:cc:subject:message-id:references:mime-version :content-type:in-reply-to; s=fm3; bh=2AVIeGLsYRfY2gau1xHzfKniV6p +PP2Kuu5BVsTbOiM=; b=XsxHUTRmn2ZCpoY9WReH2248IehU7hKD1pqlnWfU/Hp 3v5L7YbbJLPqQejKi4B1b9nS/fZOEWqbsnCzefviLpHkrtUW0Par+28vYN5w7QRX AmapRn1OOJXmNV9B2DMQHOcWAiIMpk7DV2ejcmdF1DND42apHgAfRdxOVijeYL6u lujsCxaeVLUe6JLKxXyVY59YkmeS6GwFRsTrvE7IjwXBX0B4kUF8Rl7uitGRVPed huD0hFvl56AnBb8uGd/tbXai/o8OtDxSAaTeYKI8qku1ilPSE2P5jFDJn5/KognB q7Soe4amlZ9lfV4H/ygN3bDMUub/YzHy4qZWLd0RS1w== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to:x-me-proxy :x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s=fm2; bh=2AVIeG LsYRfY2gau1xHzfKniV6p+PP2Kuu5BVsTbOiM=; b=bMXXBdCUrcTocaINm3b6vE 8VY3WrgDoE+UPd4vnkmFKCDdkTnM4VT66fS7uWbzH7PyHkf9k8g9DRefdeIry4oj DTT6OSPBS3/zJg9905H05AArqNjAK4Qtcm2auvDzZ+ngBHIVn5DcI46m21gz7K7q KN59I7bWa3SnBK3IV7EWuipP5XHbR6PlMF333icxE33AhMQRFrRMaYOJ36QvP8Oy bgxldbL2cpVjHOn2lXPJMsAfxGkyMLvidFPuYfD9IlyQT7h49ZB4d0n73ElgWRa2 /BRsXtZcbJGcrBx7inxH9UKSwZBpXCck978ZzBBdkwdxUWSGwMYW5Sd4YhetfS9w == X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgeduhedrledugdelfecutefuodetggdotefrodftvf curfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfghnecu uegrihhlohhuthemuceftddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmdenuc fjughrpeffhffvuffkfhggtggujgesthdtredttddtvdenucfhrhhomheprfgvthgvrhcu jfhuthhtvghrvghruceophgvthgvrhdrhhhuthhtvghrvghrseifhhhoqdhtrdhnvghtqe enucggtffrrghtthgvrhhnpeehhfehfffgheelgeeuudelhefgvdefveekudevjeevjeev vefggefguddufeeuveenucfkphepuddujedrvddtrdejuddruddtleenucevlhhushhtvg hrufhiiigvpedtnecurfgrrhgrmhepmhgrihhlfhhrohhmpehpvghtvghrrdhhuhhtthgv rhgvrhesfihhohdqthdrnhgvth X-ME-Proxy: Received: from koala (117-20-71-109.751447.bne.nbn.aussiebb.net [117.20.71.109]) by mail.messagingengine.com (Postfix) with ESMTPA id 49C8A328005A; Tue, 12 May 2020 01:19:29 -0400 (EDT) Date: Tue, 12 May 2020 15:19:25 +1000 From: Peter Hutterer To: Dmitry Torokhov Cc: Yariv , linux-input@vger.kernel.org Subject: Re: PROBLEM: Apple external Trackpad event timestamps are jittery (regression) Message-ID: <20200512051925.GA48688@koala> References: <20200511201118.GW89269@dtor-ws> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200511201118.GW89269@dtor-ws> Sender: linux-input-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-input@vger.kernel.org On Mon, May 11, 2020 at 01:11:18PM -0700, Dmitry Torokhov wrote: > Hi, > > On Mon, May 11, 2020 at 09:18:15AM +0300, Yariv wrote: > > Using a vanilla installation of Ubuntu 20.04 (kernel v5.4), the > > timestamps of input events from my Apple "Magic Trackpad" - 1st > > generation, connected over Bluetooth - are jittery. > > This is a kernel regression. I bisected the bug. > > Do you see the same jitter when connected over USB? Can you also see if > there is similar jitter when you parse timestamps of SYN_RPEORT events > from "evtest"? > > Could you post a sample of events generated by device (via evtest)? unrelated, but I really recommend using 'libinput record' these days since it can be replayed (libinput replay) or analysed easier (it's YAML). Also, it prints delta times into the recording so you can immediately check those without having to parse them, e.g.: - evdev: - [ 0, 375974, 2, 0, 5] # EV_REL / REL_X 5 - [ 0, 375974, 2, 1, -2] # EV_REL / REL_Y -2 - [ 0, 375974, 0, 0, 0] # ------------ SYN_REPORT (0) ---------- +8ms Cheers, Peter