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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 55D9CC4332F for ; Fri, 15 Oct 2021 19:21:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3CBDC610D2 for ; Fri, 15 Oct 2021 19:21:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242685AbhJOTXj (ORCPT ); Fri, 15 Oct 2021 15:23:39 -0400 Received: from relay10.mail.gandi.net ([217.70.178.230]:44819 "EHLO relay10.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242537AbhJOTXh (ORCPT ); Fri, 15 Oct 2021 15:23:37 -0400 Received: (Authenticated sender: alexandre.belloni@bootlin.com) by relay10.mail.gandi.net (Postfix) with ESMTPSA id 92AEC240006; Fri, 15 Oct 2021 19:21:29 +0000 (UTC) From: Alexandre Belloni To: Alessandro Zummo , Alexandre Belloni Cc: linux-rtc@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 5/7] rtc: add BSM parameter Date: Fri, 15 Oct 2021 21:21:18 +0200 Message-Id: <20211015192121.817642-6-alexandre.belloni@bootlin.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20211015192121.817642-1-alexandre.belloni@bootlin.com> References: <20211015192121.817642-1-alexandre.belloni@bootlin.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org BSM or Backup Switch Mode is a common feature on RTCs, allowing to select how the RTC will decide when to switch from its primary power supply to the backup power supply. It is necessary to be able to set it from userspace as there are uses cases where it has to be done dynamically. Supported values are: RTC_BSM_DISABLED: disabled RTC_BSM_DIRECT: switching will happen as soon as Vbackup > Vdd RTC_BSM_LEVEL: switching will happen around a threshold, usually with an hysteresis RTC_BSM_STANDBY: switching will not happen until Vdd > Vbackup, this is useful to ensure the RTC doesn't draw any power until the device is first powered on. Signed-off-by: Alexandre Belloni --- drivers/rtc/dev.c | 10 ++++++++-- include/linux/rtc.h | 2 ++ include/uapi/linux/rtc.h | 9 ++++++++- 3 files changed, 18 insertions(+), 3 deletions(-) diff --git a/drivers/rtc/dev.c b/drivers/rtc/dev.c index abee1fc4705e..e104972a28fd 100644 --- a/drivers/rtc/dev.c +++ b/drivers/rtc/dev.c @@ -409,7 +409,10 @@ static long rtc_dev_ioctl(struct file *file, break; default: - err = -EINVAL; + if (rtc->ops->param_get) + err = rtc->ops->param_get(rtc->dev.parent, ¶m); + else + err = -EINVAL; } if (!err) @@ -436,7 +439,10 @@ static long rtc_dev_ioctl(struct file *file, return rtc_set_offset(rtc, param.svalue); default: - err = -EINVAL; + if (rtc->ops->param_set) + err = rtc->ops->param_set(rtc->dev.parent, ¶m); + else + err = -EINVAL; } break; diff --git a/include/linux/rtc.h b/include/linux/rtc.h index 354e0843ab17..47fd1c2d3a57 100644 --- a/include/linux/rtc.h +++ b/include/linux/rtc.h @@ -66,6 +66,8 @@ struct rtc_class_ops { int (*alarm_irq_enable)(struct device *, unsigned int enabled); int (*read_offset)(struct device *, long *offset); int (*set_offset)(struct device *, long offset); + int (*param_get)(struct device *, struct rtc_param *param); + int (*param_set)(struct device *, struct rtc_param *param); }; struct rtc_device; diff --git a/include/uapi/linux/rtc.h b/include/uapi/linux/rtc.h index 04da6c3082b3..dbbab0dbc8c8 100644 --- a/include/uapi/linux/rtc.h +++ b/include/uapi/linux/rtc.h @@ -132,11 +132,18 @@ struct rtc_param { #define RTC_FEATURE_UPDATE_INTERRUPT 3 #define RTC_FEATURE_NEED_WEEK_DAY 4 #define RTC_FEATURE_CORRECTION 5 -#define RTC_FEATURE_CNT 6 +#define RTC_FEATURE_BACKUP_SWITCH_MODE 6 +#define RTC_FEATURE_CNT 7 /* parameter list */ #define RTC_PARAM_FEATURES 0 #define RTC_PARAM_CORRECTION 1 +#define RTC_PARAM_BACKUP_SWITCH_MODE 2 + +#define RTC_BSM_DISABLED 0 +#define RTC_BSM_DIRECT 1 +#define RTC_BSM_LEVEL 2 +#define RTC_BSM_STANDBY 3 #define RTC_MAX_FREQ 8192 -- 2.31.1