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 44F36C433EF for ; Wed, 6 Apr 2022 13:56:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233889AbiDFN6p (ORCPT ); Wed, 6 Apr 2022 09:58:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47676 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234303AbiDFN6P (ORCPT ); Wed, 6 Apr 2022 09:58:15 -0400 Received: from relay8-d.mail.gandi.net (relay8-d.mail.gandi.net [217.70.183.201]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AE8D813CA2A; Wed, 6 Apr 2022 02:10:21 -0700 (PDT) Received: (Authenticated sender: alexandre.belloni@bootlin.com) by mail.gandi.net (Postfix) with ESMTPSA id BDD191BF20C; Wed, 6 Apr 2022 09:10:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1649236219; 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=VQ63HwvnHGrZcb0MV+Lbc8R18sMVO+IEaXijo5IJKi0=; b=KP4qyotP0+4BE/6EF2wTNEs6vuJZadjtA0gF1RPOUne3opDxjRA45bb3NFqdEOq7CkvZ2o 5h3G+EI8o7oufH/8ygDWxWBn7WWids8pd+pdjOjKg0W0vLuCYL7W/m4SCYcu58wvUKxQgG Xg7MEsiuxPi1Z5mkOr/vPSjlbolN5BqWZWfrJHXu6XUwT+3tte1Ji46LGhRlYJ1bi3H572 7hV4KNGCio9LegIDlXvTvC50wRaRBHY8TyTv1mHcJFt69CtX/yeDJEB59dhhA/R+p4UFkH RGT0eE/2gEscIz/EVO8ERYVWYy0CR6BWI7rTSbB6szhYETEO4ZPD2qLQGCfcpA== Date: Wed, 6 Apr 2022 11:10:17 +0200 From: Alexandre Belloni To: Miquel Raynal Cc: Alessandro Zummo , Rob Herring , devicetree@vger.kernel.org, Krzysztof Kozlowski , linux-renesas-soc@vger.kernel.org, Magnus Damm , Gareth Williams , Phil Edworthy , Geert Uytterhoeven , Stephen Boyd , Michael Turquette , linux-clk@vger.kernel.org, Milan Stevanovic , Jimmy Lalande , Pascal Eberhard , Thomas Petazzoni , Herve Codina , Clement Leger , linux-rtc@vger.kernel.org Subject: Re: [PATCH 4/7] rtc: rzn1: Add alarm support Message-ID: References: <20220405184716.1578385-1-miquel.raynal@bootlin.com> <20220405184716.1578385-5-miquel.raynal@bootlin.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220405184716.1578385-5-miquel.raynal@bootlin.com> Precedence: bulk List-ID: X-Mailing-List: linux-rtc@vger.kernel.org On 05/04/2022 20:47:13+0200, Miquel Raynal wrote: > The RZN1 RTC can trigger an interrupt when reaching a particular date up > to 7 days ahead. Bring support for this alarm. > > One drawback though, the granularity is about a minute. > > Signed-off-by: Miquel Raynal > --- > drivers/rtc/rtc-rzn1.c | 108 +++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 108 insertions(+) > > diff --git a/drivers/rtc/rtc-rzn1.c b/drivers/rtc/rtc-rzn1.c > index 15c533333930..85c5a68944a0 100644 > --- a/drivers/rtc/rtc-rzn1.c > +++ b/drivers/rtc/rtc-rzn1.c > @@ -154,14 +154,110 @@ static int rzn1_rtc_set_time(struct device *dev, struct rtc_time *tm) > return ret; > } > > +static irqreturn_t rzn1_rtc_alarm_irq(int irq, void *dev_id) > +{ > + struct rzn1_rtc *rtc = dev_id; > + > + rtc_update_irq(rtc->rtcdev, 1, RTC_AF | RTC_IRQF); > + > + return IRQ_HANDLED; > +} > + > +static int rzn1_rtc_alarm_irq_enable(struct device *dev, unsigned int enable) > +{ > + struct rzn1_rtc *rtc = dev_get_drvdata(dev); > + u32 ctl1 = readl(rtc->base + RZN1_RTC_CTL1); > + > + if (enable) > + ctl1 |= RZN1_RTC_CTL1_ALME; > + else > + ctl1 &= ~RZN1_RTC_CTL1_ALME; > + > + writel(ctl1, rtc->base + RZN1_RTC_CTL1); > + > + return 0; > +} > + > +static int rzn1_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) > +{ > + struct rzn1_rtc *rtc = dev_get_drvdata(dev); > + struct rtc_time *tm = &alrm->time; > + unsigned int min, hour, wday, delta_days; > + u32 ctl1; > + int ret; > + > + ret = rzn1_rtc_read_time(dev, tm); > + if (ret) > + return ret; > + > + min = readl(rtc->base + RZN1_RTC_ALM); > + hour = readl(rtc->base + RZN1_RTC_ALH); > + wday = readl(rtc->base + RZN1_RTC_ALW); > + > + tm->tm_sec = 0; > + tm->tm_min = bcd2bin(min); > + tm->tm_hour = bcd2bin(hour); > + delta_days = ((fls(wday) - 1) - tm->tm_wday + 7) % 7; > + tm->tm_wday = fls(wday) - 1; > + tm->tm_mday += delta_days; > + if (delta_days > rtc_month_days(tm->tm_mon, tm->tm_year)) { > + tm->tm_mday %= rtc_month_days(tm->tm_mon, tm->tm_year); > + tm->tm_mon++; > + } > + if (tm->tm_mon > 12) { > + tm->tm_mon %= 12; > + tm->tm_year++; > + } I guess you could avoid having to handle rollover by making the calculations on a time64_t and then convert back to a tm. I don't think this would be much worse in terms of processing. > + > + ctl1 = readl(rtc->base + RZN1_RTC_CTL1); > + alrm->enabled = !!(ctl1 & RZN1_RTC_CTL1_ALME); > + > + return 0; > +} > + > +static int rzn1_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) > +{ > + struct rzn1_rtc *rtc = dev_get_drvdata(dev); > + struct rtc_time *tm = &alrm->time, tm_now; > + unsigned long alarm, farest; > + unsigned int days_ahead, wday; > + int ret; > + > + ret = rzn1_rtc_read_time(dev, &tm_now); > + if (ret) > + return ret; > + > + /* We cannot set alarms more than one week ahead */ > + farest = rtc_tm_to_time64(&tm_now) + (7 * 86400); > + alarm = rtc_tm_to_time64(tm); > + if (time_after(alarm, farest)) > + return -EOPNOTSUPP; > + I would return -ERANGE > + /* Convert alarm day into week day */ > + days_ahead = tm->tm_mday - tm_now.tm_mday; > + wday = (tm_now.tm_wday + days_ahead) % 7; > + > + writel(bin2bcd(tm->tm_min), rtc->base + RZN1_RTC_ALM); > + writel(bin2bcd(tm->tm_hour), rtc->base + RZN1_RTC_ALH); > + writel(BIT(wday), rtc->base + RZN1_RTC_ALW); > + > + rzn1_rtc_alarm_irq_enable(dev, alrm->enabled); > + > + return 0; > +} > + > static const struct rtc_class_ops rzn1_rtc_ops = { > .read_time = rzn1_rtc_read_time, > .set_time = rzn1_rtc_set_time, > + .read_alarm = rzn1_rtc_read_alarm, > + .set_alarm = rzn1_rtc_set_alarm, > + .alarm_irq_enable = rzn1_rtc_alarm_irq_enable, > }; > > static int rzn1_rtc_probe(struct platform_device *pdev) > { > struct rzn1_rtc *rtc; > + int alarm_irq; > int ret; > > rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL); > @@ -178,12 +274,17 @@ static int rzn1_rtc_probe(struct platform_device *pdev) > if (IS_ERR(rtc->base)) > return dev_err_probe(&pdev->dev, PTR_ERR(rtc->base), "Missing reg\n"); > > + alarm_irq = platform_get_irq(pdev, 0); > + if (alarm_irq < 0) > + return dev_err_probe(&pdev->dev, alarm_irq, "Missing timer IRQ\n"); > + > rtc->rtcdev = devm_rtc_allocate_device(&pdev->dev); > if (IS_ERR(rtc->rtcdev)) > return PTR_ERR(rtc); > > rtc->rtcdev->range_max = 3178591199UL; /* 100 years */ > rtc->rtcdev->ops = &rzn1_rtc_ops; > + set_bit(RTC_FEATURE_ALARM_RES_MINUTE, rtc->rtcdev->features); You should probably clear RTC_FEATURE_UPDATE_INTERRUPT too. > > ret = r9a06g032_sysctrl_enable_rtc(true); > if (ret) > @@ -206,6 +307,13 @@ static int rzn1_rtc_probe(struct platform_device *pdev) > /* Enable counter operation */ > writel(0, rtc->base + RZN1_RTC_CTL2); > > + ret = devm_request_irq(&pdev->dev, alarm_irq, rzn1_rtc_alarm_irq, 0, > + dev_name(&pdev->dev), rtc); > + if (ret) { > + dev_err(&pdev->dev, "RTC timer interrupt not available\n"); > + goto disable_clk; > + } > + > ret = devm_rtc_register_device(rtc->rtcdev); > if (ret) { > dev_err(&pdev->dev, "Failed to register RTC\n"); > -- > 2.27.0 > -- Alexandre Belloni, co-owner and COO, Bootlin Embedded Linux and Kernel engineering https://bootlin.com