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=-2.3 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 18A4DC35280 for ; Mon, 30 Sep 2019 16:32:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E39B121855 for ; Mon, 30 Sep 2019 16:32:13 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=lunn.ch header.i=@lunn.ch header.b="1YJGbspz" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732008AbfI3QcN (ORCPT ); Mon, 30 Sep 2019 12:32:13 -0400 Received: from vps0.lunn.ch ([185.16.172.187]:54770 "EHLO vps0.lunn.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727767AbfI3QcN (ORCPT ); Mon, 30 Sep 2019 12:32:13 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lunn.ch; s=20171124; h=In-Reply-To:Content-Type:MIME-Version:References:Message-ID: Subject:Cc:To:From:Date:Sender:Reply-To:Content-Transfer-Encoding:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=qZmq/vZ1uF91H9zblUBrI03dFEWUTL8yzpnf7lGHSRA=; b=1YJGbspzHZXDVLB+IPjixtBnBF 78wyiJv87Tac5ug/oS1uaZGWCAAU7IUysBIBn7IfosmXCBnwwLGZv5jV/3fVNxx5pzgcktZZwmvQ8 Buks5BBHmGfeAQGLrYVXGcDleNsAXg2DKjDwa/X6PzEOq2cyIvXWW/y5nDWXuj2A1+nI=; Received: from andrew by vps0.lunn.ch with local (Exim 4.92.2) (envelope-from ) id 1iEyah-0004oW-L2; Mon, 30 Sep 2019 18:32:03 +0200 Date: Mon, 30 Sep 2019 18:32:03 +0200 From: Andrew Lunn To: Oleksandr Suvorov Cc: "linux-kernel@vger.kernel.org" , Marcel Ziswiler , Jamie Lentin , "linux-pm@vger.kernel.org" , Igor Opaniuk , "devicetree@vger.kernel.org" , Sebastian Reichel , Rob Herring , Mark Rutland Subject: Re: [PATCH 0/2] This patch introduces a feature to force gpio-poweroff module Message-ID: <20190930163203.GC15343@lunn.ch> References: <20190930103531.13764-1-oleksandr.suvorov@toradex.com> <20190930121440.GC13301@lunn.ch> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org On Mon, Sep 30, 2019 at 02:11:59PM +0000, Oleksandr Suvorov wrote: > Hi Andrew, > > On Mon, Sep 30, 2019 at 3:16 PM Andrew Lunn wrote: > > > > On Mon, Sep 30, 2019 at 10:35:36AM +0000, Oleksandr Suvorov wrote: > > > to register its own pm_power_off handler even if someone has registered > > > this handler earlier. > > > Useful to change a way to power off the system using DT files. > > > > Hi Oleksandr > > > > I'm not sure this is a good idea. What happens when there are two > > drivers using forced mode? You then get which ever is register last. > > Non deterministic behaviour. > > You're right, we have to handle a case when gpio-poweroff fails to > power the system off. Please look at the > 2nd version of the patchset. > > There are 3 only drivers that forcibly register its own pm_power_off > handler even if it has been registered before. > > drivers/firmware/efi/reboot.c - supports chained call of next > pm_power_off handler if its own handler fails. > > arch/x86/platform/iris/iris.c, drivers/char/ipmi/ipmi_poweroff.c - > don't support calling of next pm_power_off handler. > Looks like these drivers should be fixed too. > > All other drivers don't change already initialized pm_power_off handler. > > > What is the other driver which is causing you problems? How is it > > getting probed? DT? > > There are several PMUs, RTCs, watchdogs that register their own pm_power_off. > Most of them, probably not all, are probed from DT. And which specific one is causing you problems. I don't like this forced parameter. No other driver is using it. Maybe we should change this driver to support chained pm_power_off handlers? Andrew