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 X-Spam-Level: X-Spam-Status: No, score=-5.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A8971C43387 for ; Mon, 14 Jan 2019 22:26:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8420720657 for ; Mon, 14 Jan 2019 22:26:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726708AbfANW0E (ORCPT ); Mon, 14 Jan 2019 17:26:04 -0500 Received: from mail.bootlin.com ([62.4.15.54]:35547 "EHLO mail.bootlin.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726592AbfANW0E (ORCPT ); Mon, 14 Jan 2019 17:26:04 -0500 Received: by mail.bootlin.com (Postfix, from userid 110) id B08C82074F; Mon, 14 Jan 2019 23:26:01 +0100 (CET) Received: from localhost (lfbn-1-17122-186.w86-248.abo.wanadoo.fr [86.248.186.186]) by mail.bootlin.com (Postfix) with ESMTPSA id 7DC85206A6; Mon, 14 Jan 2019 23:25:51 +0100 (CET) Date: Mon, 14 Jan 2019 23:25:51 +0100 From: Alexandre Belloni To: Nick Crews Cc: linux-kernel@vger.kernel.org, groeck@chromium.org, sjg@chromium.org, dlaurie@chromium.org, Duncan Laurie , linux-rtc@vger.kernel.org, Enric Balletbo i Serra , Alessandro Zummo , Benson Leung Subject: Re: [PATCH v2 5/9] platform/chrome: rtc: Add RTC driver for Wilco EC Message-ID: <20190114222551.GC2589@piout.net> References: <20190114220356.108916-1-ncrews@google.com> <20190114220356.108916-6-ncrews@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190114220356.108916-6-ncrews@google.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-rtc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-rtc@vger.kernel.org Hello, On 14/01/2019 15:03:52-0700, Nick Crews wrote: > diff --git a/drivers/rtc/rtc-wilco-ec.c b/drivers/rtc/rtc-wilco-ec.c > new file mode 100644 > index 000000000000..d8ed791da82d > --- /dev/null > +++ b/drivers/rtc/rtc-wilco-ec.c > @@ -0,0 +1,178 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * RTC interface for Wilco Embedded Controller with R/W abilities > + * > + * Copyright 2018 Google LLC > + * > + * The corresponding platform device is typically registered in > + * drivers/platform/chrome/wilco_ec/core.c > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +#define DRV_NAME "rtc-wilco-ec" Please get rid of that define. > +int wilco_ec_rtc_read(struct device *dev, struct rtc_time *tm) > +{ > + struct wilco_ec_device *ec = dev_get_drvdata(dev->parent); > + u8 param = EC_CMOS_TOD_READ; > + struct ec_rtc_read rtc; > + struct wilco_ec_message msg = { > + .type = WILCO_EC_MSG_LEGACY, > + .flags = WILCO_EC_FLAG_RAW_RESPONSE, > + .command = EC_COMMAND_CMOS, > + .request_data = ¶m, > + .request_size = sizeof(param), > + .response_data = &rtc, > + .response_size = sizeof(rtc), > + }; > + struct rtc_time calc_tm; > + unsigned long time; > + int ret; > + > + ret = wilco_ec_mailbox(ec, &msg); > + if (ret < 0) > + return ret; > + > + tm->tm_sec = rtc.second; > + tm->tm_min = rtc.minute; > + tm->tm_hour = rtc.hour; > + tm->tm_mday = rtc.day; > + /* > + * The RTC stores the month value as 1-12 but the kernel expects 0-11, > + * so ensure invalid/zero month value from RTC is not converted to -1. I'm pretty sure this is not necessary and will certainly make the core think the date is valid when it has obviously been corrupted. > + */ > + tm->tm_mon = rtc.month ? rtc.month - 1 : 0; > + tm->tm_year = rtc.year + (rtc.century * 100) - 1900; > + tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year); > + > + /* Compute day of week */ > + rtc_tm_to_time(tm, &time); > + rtc_time_to_tm(time, &calc_tm); > + tm->tm_wday = calc_tm.tm_wday; Do you really need an accurate wday? There are no userspace applications that I know of that care and converting back and forth is quite expensive. > + > + return 0; > +} > + > +int wilco_ec_rtc_write(struct device *dev, struct rtc_time *tm) > +{ > + struct wilco_ec_device *ec = dev_get_drvdata(dev->parent); > + struct ec_rtc_write rtc; > + struct wilco_ec_message msg = { > + .type = WILCO_EC_MSG_LEGACY, > + .flags = WILCO_EC_FLAG_RAW_RESPONSE, > + .command = EC_COMMAND_CMOS, > + .request_data = &rtc, > + .request_size = sizeof(rtc), > + }; > + int year = tm->tm_year + 1900; > + /* Convert from 0=Sunday to 0=Saturday for the EC */ > + int wday = tm->tm_wday == 6 ? 0 : tm->tm_wday + 1; I'm not sure how useful it is to set an accurate wday when the RTC is not able to give it back. > + int ret; > + > + rtc.param = EC_CMOS_TOD_WRITE; > + rtc.century = bin2bcd(year / 100); > + rtc.year = bin2bcd(year % 100); > + rtc.month = bin2bcd(tm->tm_mon + 1); > + rtc.day = bin2bcd(tm->tm_mday); > + rtc.hour = bin2bcd(tm->tm_hour); > + rtc.minute = bin2bcd(tm->tm_min); > + rtc.second = bin2bcd(tm->tm_sec); > + rtc.weekday = bin2bcd(wday); > + > + ret = wilco_ec_mailbox(ec, &msg); > + if (ret < 0) > + return ret; > + > + return 0; > +} > + > +static const struct rtc_class_ops wilco_ec_rtc_ops = { > + .read_time = wilco_ec_rtc_read, > + .set_time = wilco_ec_rtc_write, > +}; > + > +static int wilco_ec_rtc_probe(struct platform_device *pdev) > +{ > + struct rtc_device *rtc = devm_rtc_device_register(&pdev->dev, > + DRV_NAME, > + &wilco_ec_rtc_ops, > + THIS_MODULE); Please use devm_rtc_allocate_device() and set rtc->range_min and rtc->range_max before registering with rtc_register_device(). > + if (IS_ERR(rtc)) > + return PTR_ERR(rtc); > + > + return 0; > +} > + > +static struct platform_driver wilco_ec_rtc_driver = { > + .driver = { > + .name = DRV_NAME, > + }, > + .probe = wilco_ec_rtc_probe, > +}; > + > +module_platform_driver(wilco_ec_rtc_driver); > + > +MODULE_ALIAS("platform:" DRV_NAME); > +MODULE_AUTHOR("Nick Crews "); > +MODULE_LICENSE("GPL v2"); > +MODULE_DESCRIPTION("Wilco EC RTC driver"); > -- > 2.20.1.97.g81188d93c3-goog > -- Alexandre Belloni, Bootlin Embedded Linux and Kernel engineering https://bootlin.com