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=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no 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 E073CC433EF for ; Tue, 14 Sep 2021 23:42:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C1F8B6108F for ; Tue, 14 Sep 2021 23:42:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235957AbhINXn2 (ORCPT ); Tue, 14 Sep 2021 19:43:28 -0400 Received: from mta-02.yadro.com ([89.207.88.252]:43076 "EHLO mta-01.yadro.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S233774AbhINXn1 (ORCPT ); Tue, 14 Sep 2021 19:43:27 -0400 Received: from localhost (unknown [127.0.0.1]) by mta-01.yadro.com (Postfix) with ESMTP id CDE5942413; Tue, 14 Sep 2021 23:42:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=yadro.com; h= content-transfer-encoding:mime-version:user-agent:content-type :content-type:organization:references:in-reply-to:date:date:from :from:subject:subject:message-id:received:received:received; s= mta-01; t=1631662926; x=1633477327; bh=R5bpcvsT3kXYqwQ+cjx1HLt+j CeJZyVa9dVb6M+UHRc=; b=Tau0ZGRzI41Vrwpo448vEHSwjzNgq/xoACMaGw0PZ PskR3K/6q0CWV7yu0pDusI8qIx1TNfvL9m3KUcDzUasmD8GUroN/Ey9bUFk5a9SR cDM/BA0FfGfG1/xhErLeoJpTCe+jnB8c+gb3qPn1wxYTsMVlkifUjLtbZiajufQv N0= X-Virus-Scanned: amavisd-new at yadro.com Received: from mta-01.yadro.com ([127.0.0.1]) by localhost (mta-01.yadro.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id For72AKW95pQ; Wed, 15 Sep 2021 02:42:06 +0300 (MSK) Received: from T-EXCH-04.corp.yadro.com (t-exch-04.corp.yadro.com [172.17.100.104]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by mta-01.yadro.com (Postfix) with ESMTPS id 1EB6A423EF; Wed, 15 Sep 2021 02:42:05 +0300 (MSK) Received: from [10.199.0.2] (10.199.0.2) by T-EXCH-04.corp.yadro.com (172.17.100.104) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384_P384) id 15.1.669.32; Wed, 15 Sep 2021 02:42:05 +0300 Message-ID: <8f47c350219719cbd8706ebc079b064cfa43ce95.camel@yadro.com> Subject: Re: [PATCH 0/2] rtc: pch-rtc: add Intel Series PCH built-in read-only RTC From: Ivan Mikhaylov To: Alexandre Belloni , Milton Miller II CC: Paul Fertser , Alessandro Zummo , , Date: Wed, 15 Sep 2021 02:52:55 +0300 In-Reply-To: References: <20210810154436.125678-1-i.mikhaylov@yadro.com> <20210814224215.GX15173@home.paul.comp> Organization: YADRO Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.38.4 (3.38.4-1.fc33) MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Originating-IP: [10.199.0.2] X-ClientProxiedBy: T-EXCH-01.corp.yadro.com (172.17.10.101) To T-EXCH-04.corp.yadro.com (172.17.100.104) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 2021-08-30 at 14:56 +0300, Ivan Mikhaylov wrote: > On Tue, 2021-08-17 at 22:05 +0200, Alexandre Belloni wrote: > > On 17/08/2021 18:04:09+0000, Milton Miller II wrote: > > > > > > On Aug 16, 2021, Alexandre Belloni wrote: > > > > On 15/08/2021 01:42:15+0300, Paul Fertser wrote: > > > > > On Tue, Aug 10, 2021 at 06:44:34PM +0300, Ivan Mikhaylov wrote: > > > > > > Add RTC driver with dt binding tree document. Also this driver > > > > adds one sysfs > > > > > > attribute for host power control which I think is odd for RTC > > > > driver. > > > > > > Need I cut it off and use I2C_SLAVE_FORCE? I2C_SLAVE_FORCE is not > > > > good > > > > > > way too from my point of view. Is there any better approach? > > > > > > > > > > Reading the C620 datasheet I see this interface also allows other > > > > > commands (wake up, watchdog feeding, reboot etc.) and reading > > > > statuses > > > > > (e.g Intruder Detect, POWER_OK_BAD). > > > > > > > > > > I think if there's any plan to use anything other but RTC via this > > > > > interface then the driver should be registered as an MFD. > > > > > > > > > > > > > This is not the current thinking, if everything is integrated, then > > > > there is no issue registering a watchdog from the RTC driver. I'll > > > > let > > > > you check with Lee... > > > > > > I think the current statement is "if they are truly disjoint > > > hardware controls" then an MFD might suffice, but if they require > > > software cordination the new auxillary bus seems to be desired. > > > > > > > Honestly, the auxiliary bus doesn't provide anything that you can't do > > by registering a device in multiple subsystem from a single driver. > > (Lee Jones, Mark Brown and I did complain at the time that this was yet > > another back channel for misuses). > > > > > > > However, I'm not sure what is the correct interface for > > > > poweroff/reboot > > > > control. > > > > > > While there is a gpio interface to a simple regulator switch, > > > the project to date has been asserting direct or indirect > > > gpios etc to control the host.   If these are events to > > > trigger a change in state and not a direct state change > > > that some controller trys to follow, maybe a message delivery > > > model?   (this is not to reboot or cycle the bmc). > > > > > > milton > > > > Alexandre, gentle reminder about this one series. I can get rid off from sysfs > attribute and put it like RO rtc without any additional things for now as > starter. > > Thanks. > ping Thanks.