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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 E321BC3B1B7 for ; Fri, 14 Feb 2020 18:17:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BA2D122314 for ; Fri, 14 Feb 2020 18:17:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581704221; bh=HnWhr6/KKXYznfesNXl5gOHM6wIdNTDv3KbNna8Ndxc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=o2WCygVk3Rs9bbpAwBQ7kH7Lj5kHY6rPX0QEWz72pHW4IJOc104JkMtTsNiwtzn3j bDo0rOxiYz68E81qWOwAWLg5JUoTPHMNY+h06PryNmj220Y/IOw0ePP/K/h2oX5ePL Wnqb2jslY7/dCwqU/kt6FaTFqc8psNuYsZwwyZXU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2393319AbgBNSQ5 (ORCPT ); Fri, 14 Feb 2020 13:16:57 -0500 Received: from mail.kernel.org ([198.145.29.99]:56224 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730746AbgBNPvW (ORCPT ); Fri, 14 Feb 2020 10:51:22 -0500 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id A6FDA2465D; Fri, 14 Feb 2020 15:51:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581695481; bh=HnWhr6/KKXYznfesNXl5gOHM6wIdNTDv3KbNna8Ndxc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=osyLz0MlWwJLVhCxGdxUX8/BI+wT+TSk5+VkHYdIgzzwYbaPNCQYYXPHO3PK+TeEa Txp171XWkslZ9ZK3ocpiSQBdftjWDCA0Dyn2gDXhe9vabf+ZJHFsdruboT0QkwAezQ KvgLkQTyDKtJ6yplQuVa4PotWSws6/fLXkOfXrwk= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Christophe Roullier , Guenter Roeck , Wim Van Sebroeck , Sasha Levin , linux-watchdog@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org Subject: [PATCH AUTOSEL 5.5 113/542] drivers: watchdog: stm32_iwdg: set WDOG_HW_RUNNING at probe Date: Fri, 14 Feb 2020 10:41:45 -0500 Message-Id: <20200214154854.6746-113-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200214154854.6746-1-sashal@kernel.org> References: <20200214154854.6746-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Christophe Roullier [ Upstream commit 85fdc63fe256b595f923a69848cd99972ff446d8 ] If the watchdog hardware is already enabled during the boot process, when the Linux watchdog driver loads, it should start/reset the watchdog and tell the watchdog framework. As a result, ping can be generated from the watchdog framework (if CONFIG_WATCHDOG_HANDLE_BOOT_ENABLED is set), until the userspace watchdog daemon takes over control Fixes:4332d113c66a ("watchdog: Add STM32 IWDG driver") Signed-off-by: Christophe Roullier Reviewed-by: Guenter Roeck Link: https://lore.kernel.org/r/20191122132246.8473-1-christophe.roullier@st.com Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck Signed-off-by: Sasha Levin --- drivers/watchdog/stm32_iwdg.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/drivers/watchdog/stm32_iwdg.c b/drivers/watchdog/stm32_iwdg.c index a3a329011a06b..25188d6bbe152 100644 --- a/drivers/watchdog/stm32_iwdg.c +++ b/drivers/watchdog/stm32_iwdg.c @@ -262,6 +262,24 @@ static int stm32_iwdg_probe(struct platform_device *pdev) watchdog_set_nowayout(wdd, WATCHDOG_NOWAYOUT); watchdog_init_timeout(wdd, 0, dev); + /* + * In case of CONFIG_WATCHDOG_HANDLE_BOOT_ENABLED is set + * (Means U-Boot/bootloaders leaves the watchdog running) + * When we get here we should make a decision to prevent + * any side effects before user space daemon will take care of it. + * The best option, taking into consideration that there is no + * way to read values back from hardware, is to enforce watchdog + * being run with deterministic values. + */ + if (IS_ENABLED(CONFIG_WATCHDOG_HANDLE_BOOT_ENABLED)) { + ret = stm32_iwdg_start(wdd); + if (ret) + return ret; + + /* Make sure the watchdog is serviced */ + set_bit(WDOG_HW_RUNNING, &wdd->status); + } + ret = devm_watchdog_register_device(dev, wdd); if (ret) return ret; -- 2.20.1