Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754306Ab2F1Xz0 (ORCPT ); Thu, 28 Jun 2012 19:55:26 -0400 Received: from mail-pb0-f46.google.com ([209.85.160.46]:52591 "EHLO mail-pb0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752282Ab2F1XzY (ORCPT ); Thu, 28 Jun 2012 19:55:24 -0400 Date: Thu, 28 Jun 2012 16:55:18 -0700 From: Dmitry Torokhov To: Eric Miao Cc: linux-kernel , linux-input@vger.kernel.org, Ayan George Subject: Re: [PATCH RFC] input: fix weird issue of synaptics psmouse sync lost after resume Message-ID: <20120628235518.GA26283@core.coreip.homeip.net> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1915 Lines: 48 Hi Eric, On Sun, Jun 24, 2012 at 11:32:38PM +0800, Eric Miao wrote: > All, > > BugLink: https://bugs.launchpad.net/bugs/717970 > > So in summary, the symptom is intermittent key events lost after resume > on some machines with synaptics touchpad (seems this is synaptics _only_), > and key events loss is due to serio port reconnect after psmouse sync lost. > Removing psmouse and inserting it back during the suspend/resume process > is able to work around the issue, so the difference between psmouse_connect() > and psmouse_reconnect() is the key to the root cause of this problem. > > After comparing the two different paths, synaptics driver has its own > implementation of synaptics_reconnect(), and the missing psmouse_probe() > seems significant, the patch below added psmouse_probe() to the reconnect > process, and has been verified many times that the issue could not be reliably > reproduced. > > There are two PS/2 commands in psmouse_probe(): > > 1. PSMOUSE_CMD_GETID > 2. PSMOUSE_CMD_RESET_DIS > > The weird thing is, the PSMOUSE_CMD_GETID seems to be significant, and the > PSMOUSE_CMD_RESET_DIS is irrelevant to this issue after trying several times. > Now it's rather difficult to form a sane theory. So this patch is > really for RFC. Hmm, murky and unknown to us EC/KBC firmware code and uglies are hidden there... I issuing PSMOUSE_CMD_GETID bis fine if it makes some firmware happy and we probably should do it for all protocols, not only Synaptics. Could you please try moving calls to psmouse_reset() and psmouse_probe() in psmouse_reconnect() up, before we check if we have protocol specific reconnect handler? 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/