From patchwork Wed Mar 23 11:57:52 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alistair X-Patchwork-Id: 553871 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8828BC433EF for ; Wed, 23 Mar 2022 11:58:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235993AbiCWL7i (ORCPT ); Wed, 23 Mar 2022 07:59:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40232 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235981AbiCWL7g (ORCPT ); Wed, 23 Mar 2022 07:59:36 -0400 Received: from out4-smtp.messagingengine.com (out4-smtp.messagingengine.com [66.111.4.28]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A4A7B1129; Wed, 23 Mar 2022 04:58:03 -0700 (PDT) Received: from compute5.internal (compute5.nyi.internal [10.202.2.45]) by mailout.nyi.internal (Postfix) with ESMTP id 0CB875C017F; Wed, 23 Mar 2022 07:58:01 -0400 (EDT) Received: from mailfrontend1 ([10.202.2.162]) by compute5.internal (MEProxy); Wed, 23 Mar 2022 07:58:01 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alistair23.me; h=cc:cc:content-transfer-encoding:date:date:from:from :in-reply-to:message-id:mime-version:reply-to:sender:subject :subject:to:to; s=fm1; bh=njhFasRxl7Ia1rqX1GO6RIfc0g8n5/4PEtJNvN BVDok=; b=Y5thfAR321DMYFnFm7bhCzkSBUoOnnavryCjsHPUXb+M/fK1gc86hX 1mZB/Yrsa4ov6SpS1GYP8O4mNJPmMEfBsbgFBfd+7SyRWvm0RaVAgn3q5KvJnIMv F8s9dDqFT3+qNmWgp8DUtdGcoe8oZIDtedMig8UOYxqOZm94ip6QjBHUwcec44cL ar/zdmmvpRGpZ8vBgU+TR6CrFHrzHyE0kvvFyJfqHn6mkWVKdSqyuWBZJCtVAE89 hopavM3je5MY87re4Tfuu5mbNgih9u9M5VYcBmS8MwXQ5EPBNySrb1fX5hptYELM zYol+N/fD3T30z+S1thQ9piHi+JcQrKw== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:cc:content-transfer-encoding:date:date :from:from:in-reply-to:message-id:mime-version:reply-to:sender :subject:subject:to:to:x-me-proxy:x-me-proxy:x-me-sender :x-me-sender:x-sasl-enc; s=fm3; bh=njhFasRxl7Ia1rqX1GO6RIfc0g8n5 /4PEtJNvNBVDok=; b=mdnYcUdhuEX6a0ttheB9gooKSO65Xb2r33bLAJvwQdVqO NDL29/OuMpscze0GVQEZE+kyWpxc2aH2Hc1gDZFc7F5QUtyj3G6CiRdqskW4kgrz YCXEBufpyleb5mAugj3Mo2ZLX36RPfg8vwZJJP2PWzyswclL+3gn/Bx0qKDwZvHq zfqCv8/qx1XsOAJO6lNxAtOAQyDoTq4ojcLZIJNrAxALaewQBU36QSJ3Gm6PBOp4 2puydx4N/G8WUWeG76hDfe37UwBRIS1xeDMse/Qq6FSolJGQDSg5OX6Ladawlz4I Za3AEd+AKdTdx7x3E8AMFDqZQCcjQS5FQNd+qXKRg== X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedvvddrudegjedgfedvucetufdoteggodetrfdotf fvucfrrhhofhhilhgvmecuhfgrshhtofgrihhlpdfqfgfvpdfurfetoffkrfgpnffqhgen uceurghilhhouhhtmecufedttdenucenucfjughrpefhvffufffkofgggfestdekredtre dttdenucfhrhhomheptehlihhsthgrihhrucfhrhgrnhgtihhsuceorghlihhsthgrihhr segrlhhishhtrghirhdvfedrmhgvqeenucggtffrrghtthgvrhhnpeejleeihfdvtefgtd ethfdtgefftdeiffefjeeiffefveeuleejheejvefhffeukeenucevlhhushhtvghrufhi iigvpedtnecurfgrrhgrmhepmhgrihhlfhhrohhmpegrlhhishhtrghirhesrghlihhsth grihhrvdefrdhmvg X-ME-Proxy: Received: by mail.messagingengine.com (Postfix) with ESMTPA; Wed, 23 Mar 2022 07:57:55 -0400 (EDT) From: Alistair Francis To: shawnguo@kernel.org, linux@roeck-us.net, linux-watchdog@vger.kernel.org, s.hauer@pengutronix.de, wim@linux-watchdog.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org Cc: devicetree@vger.kernel.org, kernel@pengutronix.de, linux-imx@nxp.com, festevam@gmail.com, robh+dt@kernel.org, Alistair Francis Subject: [PATCH v4] watchdog: imx2_wdg: Allow ping on suspend Date: Wed, 23 Mar 2022 21:57:52 +1000 Message-Id: <20220323115752.360409-1-alistair@alistair23.me> X-Mailer: git-send-email 2.35.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-watchdog@vger.kernel.org The i.MX watchdog cannot be disabled by software once it has been enabled. This means that it can't be stopped before suspend. For systems that enter low power mode this is fine, as the watchdog will be automatically stopped by hardware in low power mode. Not all i.MX platforms support low power mode in the mainline kernel. For example the i.MX7D does not enter low power mode and so will be rebooted 2 minutes after entering sleep states. This patch introduces a device tree property "fsl,ping-during-suspend" that can be used to enable ping on suspend support for these systems. Signed-off-by: Alistair Francis Reviewed-by: Guenter Roeck --- drivers/watchdog/imx2_wdt.c | 27 ++++++++++++++++++++------- 1 file changed, 20 insertions(+), 7 deletions(-) diff --git a/drivers/watchdog/imx2_wdt.c b/drivers/watchdog/imx2_wdt.c index 51bfb796898b..d0c5d47ddede 100644 --- a/drivers/watchdog/imx2_wdt.c +++ b/drivers/watchdog/imx2_wdt.c @@ -66,6 +66,7 @@ struct imx2_wdt_device { struct watchdog_device wdog; bool ext_reset; bool clk_is_on; + bool no_ping; }; static bool nowayout = WATCHDOG_NOWAYOUT; @@ -312,12 +313,18 @@ static int __init imx2_wdt_probe(struct platform_device *pdev) wdev->ext_reset = of_property_read_bool(dev->of_node, "fsl,ext-reset-output"); + /* + * The i.MX7D doesn't support low power mode, so we need to ping the watchdog + * during suspend. + */ + wdev->no_ping = !of_device_is_compatible(dev->of_node, "fsl,imx7d-wdt"); platform_set_drvdata(pdev, wdog); watchdog_set_drvdata(wdog, wdev); watchdog_set_nowayout(wdog, nowayout); watchdog_set_restart_priority(wdog, 128); watchdog_init_timeout(wdog, timeout, dev); - watchdog_stop_ping_on_suspend(wdog); + if (wdev->no_ping) + watchdog_stop_ping_on_suspend(wdog); if (imx2_wdt_is_running(wdev)) { imx2_wdt_set_timeout(wdog, wdog->timeout); @@ -366,9 +373,11 @@ static int __maybe_unused imx2_wdt_suspend(struct device *dev) imx2_wdt_ping(wdog); } - clk_disable_unprepare(wdev->clk); + if (wdev->no_ping) { + clk_disable_unprepare(wdev->clk); - wdev->clk_is_on = false; + wdev->clk_is_on = false; + } return 0; } @@ -380,11 +389,14 @@ static int __maybe_unused imx2_wdt_resume(struct device *dev) struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog); int ret; - ret = clk_prepare_enable(wdev->clk); - if (ret) - return ret; + if (wdev->no_ping) { + ret = clk_prepare_enable(wdev->clk); - wdev->clk_is_on = true; + if (ret) + return ret; + + wdev->clk_is_on = true; + } if (watchdog_active(wdog) && !imx2_wdt_is_running(wdev)) { /* @@ -407,6 +419,7 @@ static SIMPLE_DEV_PM_OPS(imx2_wdt_pm_ops, imx2_wdt_suspend, static const struct of_device_id imx2_wdt_dt_ids[] = { { .compatible = "fsl,imx21-wdt", }, + { .compatible = "fsl,imx7d-wdt", }, { /* sentinel */ } }; MODULE_DEVICE_TABLE(of, imx2_wdt_dt_ids);