From patchwork Tue Sep 1 16:17:56 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ulrich Hecht X-Patchwork-Id: 11749123 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 74DBC109A for ; Tue, 1 Sep 2020 16:30:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5B5C7206EF for ; Tue, 1 Sep 2020 16:30:12 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=fpond.eu header.i=@fpond.eu header.b="BWu07yLp" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730166AbgIAQaJ (ORCPT ); Tue, 1 Sep 2020 12:30:09 -0400 Received: from mo4-p00-ob.smtp.rzone.de ([81.169.146.219]:32952 "EHLO mo4-p00-ob.smtp.rzone.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730803AbgIAQaH (ORCPT ); Tue, 1 Sep 2020 12:30:07 -0400 X-Greylist: delayed 543 seconds by postgrey-1.27 at vger.kernel.org; Tue, 01 Sep 2020 12:30:05 EDT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; t=1598977803; s=strato-dkim-0002; d=fpond.eu; h=Message-Id:Date:Subject:Cc:To:From:X-RZG-CLASS-ID:X-RZG-AUTH:From: Subject:Sender; bh=R67TVdKPqKtVG4x1Q47JYeOebvZgXqLoj091CkvVqA0=; b=BWu07yLpEtXiQJ39IlULnZ4NKCaJ8JmHVC2uSbifiOWEpZr0WfkwLC24n5ydx0Lp4c Pz38cvgLXlZp3wIu66ALRySQFECdbkPm2IC3MeT5GUBEOzH2w68TqNhwiu5O89X4IMZP RNLfJ8mk56ELNnGglpjmz0PvS+O0I33JnEJNLqNTokIuuM7V1SBrylJ1mlW92AnJgzLk ptDXVGX6+hoZ7aMh4u4f3iXq85DidXiZLAZ3Z9PdQ5WdXEmZUF5WjBxC09y7+eFbj/Tg 56iudn5Ow3qr+8rmoxOlrxfHgJcS7YL+vDAzHB5qVa4ooP/xty+U3m8PfjyzObDkNBbX FZeQ== X-RZG-AUTH: ":OWANVUa4dPFUgKR/3dpvnYP0Np73dmm4I5W0/AvA67Ot4fvR82Nfd22JDvA=" X-RZG-CLASS-ID: mo00 Received: from groucho.site by smtp.strato.de (RZmta 46.10.7 DYNA|AUTH) with ESMTPSA id e0624aw81GI0vh3 (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256 bits)) (Client did not present a certificate); Tue, 1 Sep 2020 18:18:00 +0200 (CEST) From: Ulrich Hecht To: linux-renesas-soc@vger.kernel.org Cc: wsa@the-dreams.de, geert@linux-m68k.org, linux-i2c@vger.kernel.org, linux-watchdog@vger.kernel.org, Ulrich Hecht Subject: [PATCH] watchdog: da9063: wake up parent ahead of reboot Date: Tue, 1 Sep 2020 18:17:56 +0200 Message-Id: <20200901161756.28100-1-uli+renesas@fpond.eu> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Sender: linux-watchdog-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-watchdog@vger.kernel.org This patch ensures our parent is awake before a reboot takes place. This prevents situations in which the I2C host has been suspended and cannot be safely woken up anymore when it needs to talk to us. Signed-off-by: Ulrich Hecht --- Hi! This is supposed to resolve the issue that came up in the review of "[PATCH v2] i2c: sh_mobile: implement atomic transfers" that the parent controller may be suspended when the restart method is called. See https://www.spinics.net/lists/linux-i2c/msg46367.html for details. CU Uli drivers/watchdog/da9063_wdt.c | 21 +++++++++++++++++++++ include/linux/mfd/da9063/core.h | 2 ++ 2 files changed, 23 insertions(+) diff --git a/drivers/watchdog/da9063_wdt.c b/drivers/watchdog/da9063_wdt.c index 423584252606..89718733491e 100644 --- a/drivers/watchdog/da9063_wdt.c +++ b/drivers/watchdog/da9063_wdt.c @@ -18,6 +18,8 @@ #include #include #include +#include +#include /* * Watchdog selector to timeout in seconds. @@ -158,6 +160,21 @@ static int da9063_wdt_set_timeout(struct watchdog_device *wdd, return ret; } +static int da9063_reboot_notifier(struct notifier_block *nb, + unsigned long code, void *unused) +{ + struct da9063 *da9063 = container_of(nb, struct da9063, reboot_nb); + + /* + * Make sure parent device is running. This cannot be done in the + * restart handler because it is no longer safe to do runtime PM + * there. + */ + pm_runtime_get_sync(da9063->dev->parent); + + return NOTIFY_DONE; +} + static int da9063_wdt_restart(struct watchdog_device *wdd, unsigned long action, void *data) { @@ -233,6 +250,10 @@ static int da9063_wdt_probe(struct platform_device *pdev) set_bit(WDOG_HW_RUNNING, &wdd->status); } + /* Get early notification of reboot so we can wake up the parent. */ + da9063->reboot_nb.notifier_call = da9063_reboot_notifier; + devm_register_reboot_notifier(dev, &da9063->reboot_nb); + return devm_watchdog_register_device(dev, wdd); } diff --git a/include/linux/mfd/da9063/core.h b/include/linux/mfd/da9063/core.h index fa7a43f02f27..9a3283d488b7 100644 --- a/include/linux/mfd/da9063/core.h +++ b/include/linux/mfd/da9063/core.h @@ -85,6 +85,8 @@ struct da9063 { int chip_irq; unsigned int irq_base; struct regmap_irq_chip_data *regmap_irq; + + struct notifier_block reboot_nb; }; int da9063_device_init(struct da9063 *da9063, unsigned int irq);