From patchwork Tue Jan 28 14:03:16 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 232514 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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=unavailable 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 71006C35240 for ; Tue, 28 Jan 2020 14:39:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3EA5C207FD for ; Tue, 28 Jan 2020 14:39:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1580222393; bh=RsZ49+HuVXrU/JY3Ejeo3KXvJigAnXjCknahaYv5sjA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=bgohtmoItOTO545NEVSjBRw6yMBIeOHmLUGrUYqdw66qwHN6LkhYKeRb/aYM3AqGC RuCbqXs5jGJzD6MMCyUCnukAZbk356tk7han989QqapAmST6aZwhIv8Rf/Os8JLf/Y NksGc6naMDHUHOyrzhPtWcvIhZe7cszlaycKheJA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730323AbgA1OQg (ORCPT ); Tue, 28 Jan 2020 09:16:36 -0500 Received: from mail.kernel.org ([198.145.29.99]:40042 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730329AbgA1OQf (ORCPT ); Tue, 28 Jan 2020 09:16:35 -0500 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 866F024688; Tue, 28 Jan 2020 14:16:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1580220995; bh=RsZ49+HuVXrU/JY3Ejeo3KXvJigAnXjCknahaYv5sjA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=qUFvqiX4+824isnkeXGsvg0T+ks1DZMmOUr5+SN5hRqyYIBMHF44+vMrKz1xescOh 9Irv8WIbu1CpzUalPlUy04OjH/n21+0lUTOvdvXx8jT+ZKYUtXkrAEmb47WCN+NaiG 5niMs7VJURxxyaDzhBSNQWGhOUd+7uFFgWKPqauc= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Alexandre Belloni , Alessandro Zummo , Sylvain Chouleur , Patrick McDermott , linux-rtc@vger.kernel.org, Eric Wong , Sasha Levin Subject: [PATCH 4.9 047/271] rtc: cmos: ignore bogus century byte Date: Tue, 28 Jan 2020 15:03:16 +0100 Message-Id: <20200128135856.145846743@linuxfoundation.org> X-Mailer: git-send-email 2.25.0 In-Reply-To: <20200128135852.449088278@linuxfoundation.org> References: <20200128135852.449088278@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Eric Wong [ Upstream commit 2a4daadd4d3e507138f8937926e6a4df49c6bfdc ] Older versions of Libreboot and Coreboot had an invalid value (`3' in my case) in the century byte affecting the GM45 in the Thinkpad X200. Not everybody's updated their firmwares, and Linux <= 4.2 was able to read the RTC without problems, so workaround this by ignoring invalid values. Fixes: 3c217e51d8a272b9 ("rtc: cmos: century support") Cc: Alexandre Belloni Cc: Alessandro Zummo Cc: Sylvain Chouleur Cc: Patrick McDermott Cc: linux-rtc@vger.kernel.org Signed-off-by: Eric Wong Signed-off-by: Alexandre Belloni Signed-off-by: Sasha Levin --- drivers/rtc/rtc-mc146818-lib.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/rtc/rtc-mc146818-lib.c b/drivers/rtc/rtc-mc146818-lib.c index 2f1772a358ca5..18a6f15e313d8 100644 --- a/drivers/rtc/rtc-mc146818-lib.c +++ b/drivers/rtc/rtc-mc146818-lib.c @@ -82,7 +82,7 @@ unsigned int mc146818_get_time(struct rtc_time *time) time->tm_year += real_year - 72; #endif - if (century) + if (century > 20) time->tm_year += (century - 19) * 100; /*