From nobody Sun Feb 8 05:28:56 2026 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 3A806EB64DB for ; Thu, 22 Jun 2023 07:16:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230506AbjFVHQl (ORCPT ); Thu, 22 Jun 2023 03:16:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40432 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229732AbjFVHQi (ORCPT ); Thu, 22 Jun 2023 03:16:38 -0400 Received: from cpanel.siel.si (cpanel.siel.si [46.19.9.99]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7FCA3E69; Thu, 22 Jun 2023 00:16:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=norik.com; s=default; h=Content-Transfer-Encoding:MIME-Version:Message-Id:Date:Subject: Cc:To:From:Sender:Reply-To:Content-Type:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: In-Reply-To:References:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=fFVRpThLopAOrI7yVx0trLMYaXbzsG/TuaZoGCChqNw=; b=fSkCGMLx+NtSIbxhA4neDCIrap qFGe6/138gRm4hZ/6lRTphSY3opopD9feU9LWWb9jYjHb1/rSQlwXXewKzfOGRBe5EfEAHHpuK2s/ mDoohjOQJn+9LlH1lPSF5wTOqw0Br0Fgu2JWbKa6kRQkI7ROWwFEdAb8E9OK2JiYaQg1emlKZSj0x bhZZBs0r9SI2De+otddX/HV171HjAlQolyOEt7SqTeqzWB9xX6H4cn8P3M4G3zt3izODvQUhIeLZh 57GCiIy4UqTmLbfAkDmlQKhJTvlPMXM+DGgeZVKExbygfhDdvSZknk26suzIjPGf7YuXUl5HhppKf S7VK528g==; Received: from [89.212.21.243] (port=50578 helo=localhost.localdomain) by cpanel.siel.si with esmtpsa (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (Exim 4.96) (envelope-from ) id 1qCEYN-00GUK0-2G; Thu, 22 Jun 2023 09:16:27 +0200 From: Andrej Picej To: a.zummo@towertech.it, alexandre.belloni@bootlin.com Cc: linux-rtc@vger.kernel.org, linux-kernel@vger.kernel.org, upstream@phytec.de Subject: [PATCH v2] rtc: rv3028: Improve trickle charger logic Date: Thu, 22 Jun 2023 09:16:09 +0200 Message-Id: <20230622071609.4032736-1-andrej.picej@norik.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - cpanel.siel.si X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - norik.com X-Get-Message-Sender-Via: cpanel.siel.si: authenticated_id: andrej.picej@norik.com X-Authenticated-Sender: cpanel.siel.si: andrej.picej@norik.com X-Source: X-Source-Args: X-Source-Dir: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Property "trickle-resistor-ohms" allows us to set trickle charger resistor. However there is no possibility to disable it afterwards. From now on, disable trickle charger circuit in case device-tree property "trickle-resistor-ohms" is set to -1. Additionally, lets make sure we only update internal EEPROM in case of a change. This prevents wear due to excessive EEPROM writes on each probe. Signed-off-by: Andrej Picej --- Changes in v2: - disable trickle charger if device tree property trickle-resistor-ohms is set to -1. --- drivers/rtc/rtc-rv3028.c | 45 +++++++++++++++++++++++++++++----------- 1 file changed, 33 insertions(+), 12 deletions(-) diff --git a/drivers/rtc/rtc-rv3028.c b/drivers/rtc/rtc-rv3028.c index ec5d7a614e2d..da2ae81fe7c8 100644 --- a/drivers/rtc/rtc-rv3028.c +++ b/drivers/rtc/rtc-rv3028.c @@ -859,7 +859,8 @@ static int rv3028_probe(struct i2c_client *client) { struct rv3028_data *rv3028; int ret, status; - u32 ohms; + s32 ohms; + int val_old, val; struct nvmem_config nvmem_cfg =3D { .name =3D "rv3028_nvram", .word_size =3D 1, @@ -937,22 +938,42 @@ static int rv3028_probe(struct i2c_client *client) if (ret) return ret; =20 - /* setup trickle charger */ - if (!device_property_read_u32(&client->dev, "trickle-resistor-ohms", - &ohms)) { - int i; + ret =3D regmap_read(rv3028->regmap, RV3028_BACKUP, &val_old); + if (ret < 0) + return ret; + + /* mask out only trickle charger bits */ + val_old =3D val_old & (RV3028_BACKUP_TCE | RV3028_BACKUP_TCR_MASK); =20 - for (i =3D 0; i < ARRAY_SIZE(rv3028_trickle_resistors); i++) - if (ohms =3D=3D rv3028_trickle_resistors[i]) - break; + /* setup trickle charger */ + if (!of_property_read_s32(client->dev.of_node, "trickle-resistor-ohms", + &ohms)) { + /* disable trickle charger if trickle-resistor-ohms =3D <(-1)>; */ + if (ohms =3D=3D -1) { + val =3D val_old & ~RV3028_BACKUP_TCE; + } else { + int i; + + for (i =3D 0; i < ARRAY_SIZE(rv3028_trickle_resistors); i++) + if (ohms =3D=3D rv3028_trickle_resistors[i]) + break; + + if (i < ARRAY_SIZE(rv3028_trickle_resistors)) { + /* enable trickle charger and its resistor */ + val =3D RV3028_BACKUP_TCE | i; + } else { + dev_warn(&client->dev, "invalid trickle resistor value\n"); + /* don't update the trickle charger regs */ + val =3D val_old; + } + } =20 - if (i < ARRAY_SIZE(rv3028_trickle_resistors)) { + /* only update EEPROM if changes are necessary */ + if (val_old !=3D val) { ret =3D rv3028_update_cfg(rv3028, RV3028_BACKUP, RV3028_BACKUP_TCE | - RV3028_BACKUP_TCR_MASK, RV3028_BACKUP_TCE | i); + RV3028_BACKUP_TCR_MASK, val); if (ret) return ret; - } else { - dev_warn(&client->dev, "invalid trickle resistor value\n"); } } =20 --=20 2.25.1