From patchwork Wed Sep 18 14:44:22 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dmitry Torokhov X-Patchwork-Id: 2907251 Return-Path: X-Original-To: patchwork-linux-input@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 0A4959F1BF for ; Wed, 18 Sep 2013 14:44:52 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id E8EAC20163 for ; Wed, 18 Sep 2013 14:44:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C1E64201F4 for ; Wed, 18 Sep 2013 14:44:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752469Ab3IROof (ORCPT ); Wed, 18 Sep 2013 10:44:35 -0400 Received: from mail-pd0-f178.google.com ([209.85.192.178]:48967 "EHLO mail-pd0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752141Ab3IROoe (ORCPT ); Wed, 18 Sep 2013 10:44:34 -0400 Received: by mail-pd0-f178.google.com with SMTP id w10so7142255pde.37 for ; Wed, 18 Sep 2013 07:44:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=date:from:to:cc:subject:message-id:references:mime-version :content-type:content-disposition:in-reply-to:user-agent; bh=Y4GaR0kPHGK1rdLWRCEBB2IFY0rOaAmZEbiuNl2Fu0Y=; b=Ol87HUCFatxDNE/9pAqYJiRXSsY9i7r4sxkogbCtN0x5m4wAn6lotlYmTnQEeKlPA1 7KUge+ncI3Tpxx8tRI5iQcH7F5aPZ1jcoNi0hSsMxwAtyC4Qlpcaj/PBZYJO+Tfiwu2u 2gUb7fBL2WSl3LTGwxucjM3jhxppEeulqqr0tNMuZtxvomTLl84YEWi78t9Fgv8SS0W7 KOz+s6h1j28c//+KYwbq4DTzec22ThcCrPENNs7CKQIiEU/JibEePp8fBGu3KW6K0+su VFo5mUiSAiSENb7ob9FqNk6B9BE5upXpVCfJbePN+7SkAxOprRJJhoNHNkEDnQLmF5qe q2pg== X-Received: by 10.68.236.168 with SMTP id uv8mr20140229pbc.124.1379515473509; Wed, 18 Sep 2013 07:44:33 -0700 (PDT) Received: from mailhub.coreip.homeip.net (c-67-188-112-76.hsd1.ca.comcast.net. [67.188.112.76]) by mx.google.com with ESMTPSA id sy10sm5478956pac.15.1969.12.31.16.00.00 (version=TLSv1 cipher=RC4-SHA bits=128/128); Wed, 18 Sep 2013 07:44:32 -0700 (PDT) Date: Wed, 18 Sep 2013 07:44:22 -0700 From: Dmitry Torokhov To: Andrey Moiseev Cc: linux-input@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] Input: i8042 - i8042_flush fix for a full 8042 buffer Message-ID: <20130918144420.GB16424@core.coreip.homeip.net> References: <52399E2C.7000805@gmail.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <52399E2C.7000805@gmail.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-input-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-input@vger.kernel.org X-Spam-Status: No, score=-7.4 required=5.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED, DKIM_SIGNED, FREEMAIL_FROM, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, T_DKIM_INVALID, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Hi Andrey, On Wed, Sep 18, 2013 at 04:35:56PM +0400, Andrey Moiseev wrote: > When 8042 internal data buffer is full, the driver > erroneously decides that the controller is not present. > > I've already sent this 2 weeks ago, but that message received no comments. > Sorry about the delay. How about we rework it a bit and make flush return success/error instead of number of bytes read, like in the patch below? Thanks. diff --git a/drivers/input/serio/i8042.c b/drivers/input/serio/i8042.c index 78e4de4..52c9ebf 100644 --- a/drivers/input/serio/i8042.c +++ b/drivers/input/serio/i8042.c @@ -223,21 +223,26 @@ static int i8042_flush(void) { unsigned long flags; unsigned char data, str; - int i = 0; + int count = 0; + int retval = 0; spin_lock_irqsave(&i8042_lock, flags); - while (((str = i8042_read_status()) & I8042_STR_OBF) && (i < I8042_BUFFER_SIZE)) { - udelay(50); - data = i8042_read_data(); - i++; - dbg("%02x <- i8042 (flush, %s)\n", - data, str & I8042_STR_AUXDATA ? "aux" : "kbd"); + while ((str = i8042_read_status()) & I8042_STR_OBF) { + if (count++ < I8042_BUFFER_SIZE) { + udelay(50); + data = i8042_read_data(); + dbg("%02x <- i8042 (flush, %s)\n", + data, str & I8042_STR_AUXDATA ? "aux" : "kbd"); + } else { + retval = -EIO; + break; + } } spin_unlock_irqrestore(&i8042_lock, flags); - return i; + return retval; } /* @@ -849,7 +854,7 @@ static int __init i8042_check_aux(void) static int i8042_controller_check(void) { - if (i8042_flush() == I8042_BUFFER_SIZE) { + if (i8042_flush()) { pr_err("No controller found\n"); return -ENODEV; }