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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham 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 976A2C3A5A4 for ; Fri, 30 Aug 2019 10:42:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 73FF42073F for ; Fri, 30 Aug 2019 10:42:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727781AbfH3KmZ (ORCPT ); Fri, 30 Aug 2019 06:42:25 -0400 Received: from metis.ext.pengutronix.de ([85.220.165.71]:54285 "EHLO metis.ext.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727434AbfH3KmZ (ORCPT ); Fri, 30 Aug 2019 06:42:25 -0400 Received: from erbse.hi.pengutronix.de ([2001:67c:670:100:9e5c:8eff:fece:cdfe]) by metis.ext.pengutronix.de with esmtp (Exim 4.92) (envelope-from ) id 1i3eMJ-0006dG-AZ; Fri, 30 Aug 2019 12:42:23 +0200 Subject: Re: [PATCH] rtc: ds1307: Enable battery backup on RX8130 To: Marek Vasut , linux-rtc@vger.kernel.org Cc: Arnaud Ebalard , Alexandre Belloni , kernel@pengutronix.de References: <20190628002151.4925-1-marex@denx.de> From: Bastian Krause Message-ID: Date: Fri, 30 Aug 2019 12:42:22 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <20190628002151.4925-1-marex@denx.de> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-SA-Exim-Connect-IP: 2001:67c:670:100:9e5c:8eff:fece:cdfe X-SA-Exim-Mail-From: bst@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-rtc@vger.kernel.org Sender: linux-rtc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-rtc@vger.kernel.org Hi Marek, On 6/28/19 2:21 AM, Marek Vasut wrote: > The battery backup can be disabled on this RTC, e.g. if populated right > out of production. Force the battery backup bit on to enable it. > > Signed-off-by: Marek Vasut > Cc: Arnaud Ebalard > Cc: Alexandre Belloni > --- > drivers/rtc/rtc-ds1307.c | 7 +++++++ > 1 file changed, 7 insertions(+) > > diff --git a/drivers/rtc/rtc-ds1307.c b/drivers/rtc/rtc-ds1307.c > index 1f7e8aefc1eb..4af00cac1eff 100644 > --- a/drivers/rtc/rtc-ds1307.c > +++ b/drivers/rtc/rtc-ds1307.c > @@ -121,6 +121,8 @@ enum ds_type { > #define RX8130_REG_FLAG_AF BIT(3) > #define RX8130_REG_CONTROL0 0x1e > #define RX8130_REG_CONTROL0_AIE BIT(3) > +#define RX8130_REG_CONTROL1 0x0f I think it is surprising that RX8130_REG_CONTROL0 is defined absolute and RX8130_REG_CONTROL1 must be used with chip offset. Having this defined consistently would be nice. > +#define RX8130_REG_CONTROL1_INIEN BIT(4) > > #define MCP794XX_REG_CONTROL 0x07 > # define MCP794XX_BIT_ALM0_EN 0x10 > @@ -1750,6 +1752,11 @@ static int ds1307_probe(struct i2c_client *client, > DS1307_REG_HOUR << 4 | 0x08, hour); > } > break; > + case rx_8130: > + /* make sure that the backup battery is enabled */ > + regmap_write(ds1307->regmap, chip->offset + RX8130_REG_CONTROL1, > + RX8130_REG_CONTROL1_INIEN); > + break; Quick note: if a rechargeable battery or supercap is used the CHGEN bit must be set also. Regards, Bastian > default: > break; > } > > -- Pengutronix e.K. Industrial Linux Solutions http://www.pengutronix.de/ Peiner Str. 6-8, 31137 Hildesheim, Germany Amtsgericht Hildesheim, HRA 2686