From patchwork Mon Jan 24 12:00:27 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alistair X-Patchwork-Id: 534846 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 65543C433F5 for ; Mon, 24 Jan 2022 12:00:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238035AbiAXMAh (ORCPT ); Mon, 24 Jan 2022 07:00:37 -0500 Received: from new4-smtp.messagingengine.com ([66.111.4.230]:50995 "EHLO new4-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234568AbiAXMAg (ORCPT ); Mon, 24 Jan 2022 07:00:36 -0500 Received: from compute3.internal (compute3.nyi.internal [10.202.2.43]) by mailnew.nyi.internal (Postfix) with ESMTP id EC18258031C; Mon, 24 Jan 2022 07:00:35 -0500 (EST) Received: from mailfrontend2 ([10.202.2.163]) by compute3.internal (MEProxy); Mon, 24 Jan 2022 07:00:35 -0500 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=fm3; bh=OV6gLk/OEfbUZtYAocx2+toTLnr6A1apdN5v+9 F9RTY=; b=fLd2Y+V1a0vi9JcgwuaDt2CN8S3I07gWyFgb+e8X8bOGJz9esjhrU5 N4dH5Avtno0kPNTrNM3r2gIDa+4E9VtbP27oEYTjJ897w4XU/TZA5y8pJ+gH/qzC r3aPkvNukErE2++GQ1LCs0ILULlf7B2HSS4oEPE76uoUT9MVBQE2XJ/j8gAptbFD mIS1xVC4tUp8OvdgvXPnt/7jqLZ/7BZ3UZ8/IMOa43qgJE/w/K5w81IM7LEz0zKP CpClrOGWaU89rSljURh53xfDHbPqJk7lWRCDLKvjrE6im8DBT2D5tYyFF+R4Iu2s yDR03+rNfWwuwaDerWsYvjop6CEsvT4g== 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=fm1; bh=OV6gLk/OEfbUZtYAocx2+toTLnr6A 1apdN5v+9F9RTY=; b=R5+Qhcet9Ig/qaYUGm9RwNGuyU2SxlsZBrMPwdvFy+qqN TYjgONMtXtYdq4iirYS2/z7NpCzNCgmDNNEim8R3L3Z8YqcbPGyOHTmXfU7Vs2t4 S17yR5hDY+a3NR51jQrum1y3ThFaoXTwUtim7185KSk/fo2mF3fw8xoowWm4QNrm Ggkn1hw9uavN8JFLfne3ov2oSmDftANOU0XyMqYbtKrd0iLgczq7ovefMXeEn1em QbURZEK8CnjEXkbVMG2MBrBhDs9Gv5GqOMXh0HuyReRG3For8wQFHjblT7KuKc/O JccGHR6r+fqoWuv3qAIXqhi7xvdDoC8we8DOaliwQ== X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedvvddrvdeigdefiecutefuodetggdotefrodftvf curfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfghnecu uegrihhlohhuthemuceftddtnecunecujfgurhephffvufffkffoggfgsedtkeertdertd dtnecuhfhrohhmpeetlhhishhtrghirhcuhfhrrghntghishcuoegrlhhishhtrghirhes rghlihhsthgrihhrvdefrdhmvgeqnecuggftrfgrthhtvghrnhepjeeliefhvdetgfdtte fhtdegffdtiefffeejiefffeevueeljeehjeevhfffueeknecuvehluhhsthgvrhfuihii vgeptdenucfrrghrrghmpehmrghilhhfrhhomheprghlihhsthgrihhrsegrlhhishhtrg hirhdvfedrmhgv X-ME-Proxy: Received: by mail.messagingengine.com (Postfix) with ESMTPA; Mon, 24 Jan 2022 07:00:30 -0500 (EST) From: Alistair Francis To: linux-arm-kernel@lists.infradead.org, linux@roeck-us.net, shawnguo@kernel.org, linux-kernel@vger.kernel.org, s.hauer@pengutronix.de, linux-watchdog@vger.kernel.org, wim@linux-watchdog.org Cc: devicetree@vger.kernel.org, festevam@gmail.com, linux-imx@nxp.com, robh+dt@kernel.org, kernel@pengutronix.de, Alistair Francis Subject: [PATCH v2] watchdog: imx2_wdg: Alow ping on suspend Date: Mon, 24 Jan 2022 22:00:27 +1000 Message-Id: <20220124120027.106754-1-alistair@alistair23.me> X-Mailer: git-send-email 2.31.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-watchdog@vger.kernel.org The i.MX watchdog cannot be disabled by softwrae 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 hardwrae 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 freeze or mem 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 --- 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);