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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5C37CC88CB4 for ; Mon, 12 Jun 2023 14:07:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235853AbjFLOHw (ORCPT ); Mon, 12 Jun 2023 10:07:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50584 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236919AbjFLOHv (ORCPT ); Mon, 12 Jun 2023 10:07:51 -0400 Received: from relay5-d.mail.gandi.net (relay5-d.mail.gandi.net [IPv6:2001:4b98:dc4:8::225]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3C197A1; Mon, 12 Jun 2023 07:07:50 -0700 (PDT) X-GND-Sasl: alexandre.belloni@bootlin.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1686578868; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=8aq38QKEdBNE3WxYWJheQyTs9iqtlahhv2aTRlxzgBk=; b=jX/+gtEvZoMiCDMJQBDkRjnIA75s/XfCX8/t5AcvlG7vXZeNRBoaBtjXehnuNVWxuohyLU 03L7RexpLqk48DZWg1hLmnd2vmAX9ONYNrQa4jg+lMtPDNPsDrHQYZJXwxOoY/cH593v6R FX3w4WIkWFu7CVNLKf3g0ulSeMYS3OCnNiWABqg2o1pm7cbl5v0Z6Ex9ok6lsaHJYw0Qcf yeX0fVBTTVFRBejk8pEcOwaRStQYG8w8XUyk6JN3jDS9Z4BxLmVZgKK1n7/Jn9rIwiR1VW gZvFczwipksArk6wYIfVUWCaQ749oQkODZFfTcb5S5N4fRFHoa7yW88DR2mKGg== X-GND-Sasl: alexandre.belloni@bootlin.com X-GND-Sasl: alexandre.belloni@bootlin.com X-GND-Sasl: alexandre.belloni@bootlin.com X-GND-Sasl: alexandre.belloni@bootlin.com X-GND-Sasl: alexandre.belloni@bootlin.com X-GND-Sasl: alexandre.belloni@bootlin.com X-GND-Sasl: alexandre.belloni@bootlin.com X-GND-Sasl: alexandre.belloni@bootlin.com Received: by mail.gandi.net (Postfix) with ESMTPSA id 187BA1C0012; Mon, 12 Jun 2023 14:07:46 +0000 (UTC) Date: Mon, 12 Jun 2023 16:07:46 +0200 From: Alexandre Belloni To: Rasmus Villemoes Cc: Alessandro Zummo , Andy Shevchenko , devicetree@vger.kernel.org, Rob Herring , Krzysztof Kozlowski , Conor Dooley , linux-rtc@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 5/8] rtc: isl12022: implement RTC_VL_READ and RTC_VL_CLR ioctls Message-ID: <2023061214074623dcc0cf@mail.local> References: <20230612113059.247275-1-linux@rasmusvillemoes.dk> <20230612113059.247275-6-linux@rasmusvillemoes.dk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230612113059.247275-6-linux@rasmusvillemoes.dk> Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org On 12/06/2023 13:30:55+0200, Rasmus Villemoes wrote: > Hook up support for reading the values of the SR_LBAT85 and SR_LBAT75 > bits. Translate the former to "battery low", and the latter to > "battery empty or not-present". > > Signed-off-by: Rasmus Villemoes > --- > drivers/rtc/rtc-isl12022.c | 41 ++++++++++++++++++++++++++++++++++++++ > 1 file changed, 41 insertions(+) > > diff --git a/drivers/rtc/rtc-isl12022.c b/drivers/rtc/rtc-isl12022.c > index cb8f1d92e116..1b6659a9b33a 100644 > --- a/drivers/rtc/rtc-isl12022.c > +++ b/drivers/rtc/rtc-isl12022.c > @@ -203,7 +203,48 @@ static int isl12022_rtc_set_time(struct device *dev, struct rtc_time *tm) > return regmap_bulk_write(regmap, ISL12022_REG_SC, buf, sizeof(buf)); > } > > +static int isl12022_read_sr(struct regmap *regmap) > +{ > + int ret; > + u32 val; > + > + ret = regmap_read(regmap, ISL12022_REG_SR, &val); > + if (ret < 0) > + return ret; > + return val; > +} > + > +static int isl12022_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg) > +{ > + struct regmap *regmap = dev_get_drvdata(dev); > + u32 user = 0; > + int ret; > + > + switch (cmd) { > + case RTC_VL_READ: > + ret = isl12022_read_sr(regmap); > + if (ret < 0) > + return ret; > + > + if (ret & ISL12022_SR_LBAT85) > + user |= RTC_VL_BACKUP_LOW; > + > + if (ret & ISL12022_SR_LBAT75) > + user |= RTC_VL_BACKUP_EMPTY; > + > + return put_user(user, (u32 __user *)arg); > + > + case RTC_VL_CLR: > + return regmap_clear_bits(regmap, ISL12022_REG_SR, > + ISL12022_SR_LBAT85 | ISL12022_SR_LBAT75); I'm against using RTC_VL_CLR for this as it deletes important information (i.e. the date is probably invalid). You should let the RTC clear the bits once the battery has been changed: "The LBAT75 bit is set when the VBAT has dropped below the pre-selected trip level, and will self clear when the VBAT is above the pre-selected trip level at the next detection cycle either by manual or automatic trigger." > + > + default: > + return -ENOIOCTLCMD; > + } > +} > + > static const struct rtc_class_ops isl12022_rtc_ops = { > + .ioctl = isl12022_rtc_ioctl, > .read_time = isl12022_rtc_read_time, > .set_time = isl12022_rtc_set_time, > }; > -- > 2.37.2 > -- Alexandre Belloni, co-owner and COO, Bootlin Embedded Linux and Kernel engineering https://bootlin.com