From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtpout-04.galae.net (smtpout-04.galae.net [185.171.202.116]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 54A6530B53A; Thu, 5 Mar 2026 07:48:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.171.202.116 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772696888; cv=none; b=KlAHGN6+X0SDfwrF+ux3sHPK6V3covoDgIqEED31AzaBOrJgUA6QcU2DaPg7Nk8mAsdNZzwMqv6Rj/cAbFI9BLKYqjqWeQEfdTvVoQGueP9OIKH20CdOYuSFiHmZXJfeMfSWPi24dH7WEy8XYRDk5xKjDEh+M/fDy+KfcoYKEOs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772696888; c=relaxed/simple; bh=Ovvh/6MYV2WSyqHB9xbSPCaYhmlv1JQ0NQT+k21dghI=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=TPi5ypm7NV+9gU9u38tfec4y54wvPXGuvAr3USuixAVVANGXUu71hSP1u9/twRpuaasKHuf0CG+HYuNYFWC9PlpXUf7/TKS4wZZRQzrtB02ITe7W6rgmJAD9WsDbRJ6FfJa4HXPKVH1s7wMT49fsiF1vqmuR22fZmOQ29xpoKr0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com; spf=pass smtp.mailfrom=bootlin.com; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b=pHaZPZDn; arc=none smtp.client-ip=185.171.202.116 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=bootlin.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b="pHaZPZDn" Received: from smtpout-01.galae.net (smtpout-01.galae.net [212.83.139.233]) by smtpout-04.galae.net (Postfix) with ESMTPS id E963FC40404; Thu, 5 Mar 2026 07:48:21 +0000 (UTC) Received: from mail.galae.net (mail.galae.net [212.83.136.155]) by smtpout-01.galae.net (Postfix) with ESMTPS id 5F2A25FDEB; Thu, 5 Mar 2026 07:48:03 +0000 (UTC) Received: from [127.0.0.1] (localhost [127.0.0.1]) by localhost (Mailerdaemon) with ESMTPSA id 289351036981A; Thu, 5 Mar 2026 08:48:01 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=dkim; t=1772696882; h=from:subject:date:message-id:to:cc:mime-version:content-type: in-reply-to:references; bh=hsyLDW4nJEH6PPZ0/VDK4H6ENav77uqw47Wi4VxY1J0=; b=pHaZPZDnb7mfsmgbqkqNhzzem8M6VyZFj3UsRfACQ8vnMcmpS6z5nolKpCw1+E1OWD3vlB SxEWRQbOeR22zWMd9uetQyHlCnm1yaI6aACAmbLK7rxFBAhszqmkgooVeFDYWMfU/UaigD yPIiitmqH+W7ssYSFE6DHQUsSCsu85o95g/P2CQ0YTQrSCR7Dr4YOhoPepM6tX+1EUZrFS EV31NWCs72eWs3hpg1gUqQ1kEiqk6KkC4eHJ2sF4TX6PiHnyFh22990+EI/sBOJ5a9W8m6 mjNlIvR0A2LYLKQ4eAxvmvGPEHTXTkg01CzDMDdA93AgGUHcIk0v84lu7nI5Ow== Date: Thu, 5 Mar 2026 08:48:01 +0100 From: Alexandre Belloni To: "Rafael J. Wysocki" Cc: Linux ACPI , LKML , linux-rtc@vger.kernel.org, Linux PM Subject: Re: [PATCH v1 6/7] ACPI: TAD: Add RTC class device interface Message-ID: <20260305074801a04117a7@mail.local> References: <5092662.31r3eYUQgx@rafael.j.wysocki> <2352027.iZASKD2KPV@rafael.j.wysocki> Precedence: bulk X-Mailing-List: linux-pm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <2352027.iZASKD2KPV@rafael.j.wysocki> X-Last-TLS-Session-Version: TLSv1.3 On 04/03/2026 19:16:01+0100, Rafael J. Wysocki wrote: > From: Rafael J. Wysocki > > Add an RTC class device interface allowing to read and set the real time > value to the ACPI TAD driver. > > Signed-off-by: Rafael J. Wysocki Reviewed-by: Alexandre Belloni > --- > drivers/acpi/acpi_tad.c | 78 ++++++++++++++++++++++++++++++++++++++++++++++-- > 1 file changed, 76 insertions(+), 2 deletions(-) > > --- a/drivers/acpi/acpi_tad.c > +++ b/drivers/acpi/acpi_tad.c > @@ -25,6 +25,7 @@ > #include > #include > #include > +#include > #include > > MODULE_DESCRIPTION("ACPI Time and Alarm (TAD) Device Driver"); > @@ -51,6 +52,7 @@ MODULE_AUTHOR("Rafael J. Wysocki"); > > /* ACPI TAD RTC */ > #define ACPI_TAD_TZ_UNSPEC 2047 > +#define ACPI_TAD_TIME_ISDST 3 > > struct acpi_tad_driver_data { > u32 capabilities; > @@ -164,6 +166,8 @@ static int acpi_tad_get_real_time(struct > return 0; > } > > +/* sysfs interface */ > + > static char *acpi_tad_rt_next_field(char *s, int *val) > { > char *p; > @@ -579,6 +583,71 @@ static const struct attribute_group acpi > .is_visible = acpi_tad_attr_is_visible, > }; > > +#ifdef CONFIG_RTC_CLASS > +/* RTC class device interface */ > + > +static int acpi_tad_rtc_set_time(struct device *dev, struct rtc_time *tm) > +{ > + struct acpi_tad_rt rt; > + > + rt.year = tm->tm_year + 1900; > + rt.month = tm->tm_mon + 1; > + rt.day = tm->tm_mday; > + rt.hour = tm->tm_hour; > + rt.minute = tm->tm_min; > + rt.second = tm->tm_sec; > + rt.tz = ACPI_TAD_TZ_UNSPEC; > + rt.daylight = ACPI_TAD_TIME_ISDST * !!tm->tm_isdst; > + > + return acpi_tad_set_real_time(dev, &rt); > +} > + > +static int acpi_tad_rtc_read_time(struct device *dev, struct rtc_time *tm) > +{ > + struct acpi_tad_rt rt; > + int ret; > + > + ret = acpi_tad_get_real_time(dev, &rt); > + if (ret) > + return ret; > + > + tm->tm_year = rt.year - 1900; > + tm->tm_mon = rt.month - 1; > + tm->tm_mday = rt.day; > + tm->tm_hour = rt.hour; > + tm->tm_min = rt.minute; > + tm->tm_sec = rt.second; > + tm->tm_isdst = rt.daylight == ACPI_TAD_TIME_ISDST; > + > + return 0; > +} > + > +static const struct rtc_class_ops acpi_tad_rtc_ops = { > + .read_time = acpi_tad_rtc_read_time, > + .set_time = acpi_tad_rtc_set_time, > +}; > + > +static void acpi_tad_register_rtc(struct device *dev) > +{ > + struct rtc_device *rtc; > + > + rtc = devm_rtc_allocate_device(dev); > + if (IS_ERR(rtc)) > + return; > + > + rtc->range_min = mktime64(1900, 1, 1, 0, 0, 0); > + rtc->range_max = mktime64(9999, 12, 31, 23, 59, 59); > + > + rtc->ops = &acpi_tad_rtc_ops; > + > + devm_rtc_register_device(rtc); > +} > +#else /* !CONFIG_RTC_CLASS */ > +static inline void acpi_tad_register_rtc(struct device *dev) {} > +#endif /* !CONFIG_RTC_CLASS */ > + > +/* Platform driver interface */ > + > static int acpi_tad_disable_timer(struct device *dev, u32 timer_id) > { > return acpi_tad_wake_set(dev, "_STV", timer_id, ACPI_TAD_WAKE_DISABLED); > @@ -660,10 +729,15 @@ static int acpi_tad_probe(struct platfor > pm_runtime_suspend(dev); > > ret = sysfs_create_group(&dev->kobj, &acpi_tad_attr_group); > - if (ret) > + if (ret) { > acpi_tad_remove(pdev); > + return ret; > + } > > - return ret; > + if (caps & ACPI_TAD_RT) > + acpi_tad_register_rtc(dev); > + > + return 0; > } > > static const struct acpi_device_id acpi_tad_ids[] = { > > > -- Alexandre Belloni, co-owner and COO, Bootlin Embedded Linux and Kernel engineering https://bootlin.com