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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 8DA47C33CB6 for ; Thu, 16 Jan 2020 18:17:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6A757208C3 for ; Thu, 16 Jan 2020 18:17:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579198673; bh=yVEIWg/Qhu2H3z5ZhV7BPUrVlpawvdNKn/VbgxC5zOw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=Wqa2an09dbSeQzD0KWj6ULHbSFwySfBS2qZX9OAwRAaOILRb15/k6qWSaJn51xcqj oWWKKJfREQxVeqef6vpjUrKIfjQa9NQRzDwQvgw4DkZHDniRQChqQ+cPKILh84e3kH d8Ghm5HdN0oflzsuu6BvvzSGn25/KZ4Tc6CN7v9k= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2393031AbgAPSRs (ORCPT ); Thu, 16 Jan 2020 13:17:48 -0500 Received: from mail.kernel.org ([198.145.29.99]:40432 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2404226AbgAPR27 (ORCPT ); Thu, 16 Jan 2020 12:28:59 -0500 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 600D0246E3; Thu, 16 Jan 2020 17:28:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579195738; bh=yVEIWg/Qhu2H3z5ZhV7BPUrVlpawvdNKn/VbgxC5zOw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=M3vp3zRjuSCDdNdCVGyw2wOD2sqSFtU1zd+rl0cbvGmvwcZoi2POsgUa1UKrBxmXU HPorXdHeKq6VNeXLRhIniHZU2Mia+UU7RWkvBK6oIMFTet5EdRxEYn4Bbt+6FaHeMv 8cCyX3tyPfaYMYT+CnCl3RFmq3LZ9UjMNlqeKzZY= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Bruno Thomsen , Alexandre Belloni , Sasha Levin , linux-rtc@vger.kernel.org Subject: [PATCH AUTOSEL 4.14 275/371] rtc: pcf2127: bugfix: read rtc disables watchdog Date: Thu, 16 Jan 2020 12:22:27 -0500 Message-Id: <20200116172403.18149-218-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200116172403.18149-1-sashal@kernel.org> References: <20200116172403.18149-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-rtc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-rtc@vger.kernel.org From: Bruno Thomsen [ Upstream commit 7f43020e3bdb63d65661ed377682702f8b34d3ea ] The previous fix listed bulk read of registers as root cause of accendential disabling of watchdog, since the watchdog counter register (WD_VAL) was zeroed. Fixes: 3769a375ab83 rtc: pcf2127: bulk read only date and time registers. Tested with the same PCF2127 chip as Sean reveled root cause of WD_VAL register value zeroing was caused by reading CTRL2 register which is one of the watchdog feature control registers. So the solution is to not read the first two control registers (CTRL1 and CTRL2) in pcf2127_rtc_read_time as they are not needed anyway. Size of local buf variable is kept to allow easy usage of register defines to improve readability of code. Debug trace line was updated after CTRL1 and CTRL2 are no longer read from the chip. Also replaced magic numbers in buf access with register defines. Signed-off-by: Bruno Thomsen Link: https://lore.kernel.org/r/20190822131936.18772-3-bruno.thomsen@gmail.com Signed-off-by: Alexandre Belloni Signed-off-by: Sasha Levin --- drivers/rtc/rtc-pcf2127.c | 32 ++++++++++++-------------------- 1 file changed, 12 insertions(+), 20 deletions(-) diff --git a/drivers/rtc/rtc-pcf2127.c b/drivers/rtc/rtc-pcf2127.c index 9f1b14bf91ae..367e0f803440 100644 --- a/drivers/rtc/rtc-pcf2127.c +++ b/drivers/rtc/rtc-pcf2127.c @@ -52,20 +52,14 @@ static int pcf2127_rtc_read_time(struct device *dev, struct rtc_time *tm) struct pcf2127 *pcf2127 = dev_get_drvdata(dev); unsigned char buf[10]; int ret; - int i; - for (i = 0; i <= PCF2127_REG_CTRL3; i++) { - ret = regmap_read(pcf2127->regmap, PCF2127_REG_CTRL1 + i, - (unsigned int *)(buf + i)); - if (ret) { - dev_err(dev, "%s: read error\n", __func__); - return ret; - } - } - - ret = regmap_bulk_read(pcf2127->regmap, PCF2127_REG_SC, - (buf + PCF2127_REG_SC), - ARRAY_SIZE(buf) - PCF2127_REG_SC); + /* + * Avoid reading CTRL2 register as it causes WD_VAL register + * value to reset to 0 which means watchdog is stopped. + */ + ret = regmap_bulk_read(pcf2127->regmap, PCF2127_REG_CTRL3, + (buf + PCF2127_REG_CTRL3), + ARRAY_SIZE(buf) - PCF2127_REG_CTRL3); if (ret) { dev_err(dev, "%s: read error\n", __func__); return ret; @@ -86,14 +80,12 @@ static int pcf2127_rtc_read_time(struct device *dev, struct rtc_time *tm) } dev_dbg(dev, - "%s: raw data is cr1=%02x, cr2=%02x, cr3=%02x, " - "sec=%02x, min=%02x, hr=%02x, " + "%s: raw data is cr3=%02x, sec=%02x, min=%02x, hr=%02x, " "mday=%02x, wday=%02x, mon=%02x, year=%02x\n", - __func__, - buf[0], buf[1], buf[2], - buf[3], buf[4], buf[5], - buf[6], buf[7], buf[8], buf[9]); - + __func__, buf[PCF2127_REG_CTRL3], buf[PCF2127_REG_SC], + buf[PCF2127_REG_MN], buf[PCF2127_REG_HR], + buf[PCF2127_REG_DM], buf[PCF2127_REG_DW], + buf[PCF2127_REG_MO], buf[PCF2127_REG_YR]); tm->tm_sec = bcd2bin(buf[PCF2127_REG_SC] & 0x7F); tm->tm_min = bcd2bin(buf[PCF2127_REG_MN] & 0x7F); -- 2.20.1