From patchwork Thu Jan 27 10:47:39 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alistair X-Patchwork-Id: 537907 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 22D9FC433F5 for ; Thu, 27 Jan 2022 10:47:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239629AbiA0Krs (ORCPT ); Thu, 27 Jan 2022 05:47:48 -0500 Received: from new2-smtp.messagingengine.com ([66.111.4.224]:41489 "EHLO new2-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234845AbiA0Krr (ORCPT ); Thu, 27 Jan 2022 05:47:47 -0500 Received: from compute1.internal (compute1.nyi.internal [10.202.2.41]) by mailnew.nyi.internal (Postfix) with ESMTP id ED60C580325; Thu, 27 Jan 2022 05:47:46 -0500 (EST) Received: from mailfrontend2 ([10.202.2.163]) by compute1.internal (MEProxy); Thu, 27 Jan 2022 05:47:46 -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=/Q1y1pNtiXVQD7Pj8td3yR3lF4dB6MlMG9FvF4 asB9A=; b=ZJUc1vFbckXRuLXAH+4BAKpDs6sBuFQboo1i2ZLMdV1kvPse0uSRGs r7pwkRL7/lT2S4v7nCZir+ttB3ofPrAsz0kvqz9AenmGoa55AdhMcE8u6zWj0a87 WUQCHiadFyCR/CgLXoIM271ywrC38UZbd+dkfAfRlHgBVq7cfZ6hx1Kdm7QPTw2b 2VPAygt3KScZsKLXeZCfsCl8WV3rM3tL6yadqA7e9q2pUFYf1BkqnyLw0zfwXQ3r qs5lsq+cYJDPuZFTzuv5CxJ+LvOIT+N/LoipCgVhMky22/z03zKHbifkShA3zSUg mSynnTDRUjm1t50vNQv+lLyCV7db1ezg== 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=/Q1y1pNtiXVQD7Pj8td3yR3lF4dB6 MlMG9FvF4asB9A=; b=CnVBCJZEpRh2fGtMjofaZNYrW+PgmJ7cdbp+I6JA/vC7n qBImVv6CM4Vj752QAPc27ODkN+3sNdT5kT6nN/S127zanANQ/NyB/5PveZQK69pF jjz/H3GwNLjbm4LPm2IeA/cK4vWEulOwmLLFwqWXAO7zV/cq5x7WgUUj+6DU3Qfm kHGt48kZE8GvYH3pc0VMuz4ley4PN/WSys893LFpjILz8Wz0A6FNGuChp/Kb5bc/ GXM8EEYb0JNDQJ2P1oZm1fIh06TwnBUsT6QCNzpXzTrMhLYlsk1ifux6Fk5LTLyH zcztcNnNM7awMAVe9ZQ5tF25f5GsHSkidmI4/gnCA== X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedvvddrfeefgddvtdcutefuodetggdotefrodftvf curfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfghnecu uegrihhlohhuthemuceftddtnecuogfuohhrthgvugftvggtihhpvdculdegtddmnecujf gurhephffvufffkffoggfgsedtkeertdertddtnecuhfhrohhmpeetlhhishhtrghirhcu hfhrrghntghishcuoegrlhhishhtrghirhesrghlihhsthgrihhrvdefrdhmvgeqnecugg ftrfgrthhtvghrnhepjeeliefhvdetgfdttefhtdegffdtiefffeejiefffeevueeljeeh jeevhfffueeknecuvehluhhsthgvrhfuihiivgeptdenucfrrghrrghmpehmrghilhhfrh homheprghlihhsthgrihhrsegrlhhishhtrghirhdvfedrmhgv X-ME-Proxy: Received: by mail.messagingengine.com (Postfix) with ESMTPA; Thu, 27 Jan 2022 05:47:42 -0500 (EST) From: Alistair Francis To: linux-arm-kernel@lists.infradead.org, linux-watchdog@vger.kernel.org, linux-kernel@vger.kernel.org, shawnguo@kernel.org, wim@linux-watchdog.org, linux@roeck-us.net, s.hauer@pengutronix.de Cc: robh+dt@kernel.org, linux-imx@nxp.com, devicetree@vger.kernel.org, kernel@pengutronix.de, festevam@gmail.com, Alistair Francis Subject: [PATCH v3] watchdog: imx2_wdg: Alow ping on suspend Date: Thu, 27 Jan 2022 20:47:39 +1000 Message-Id: <20220127104739.312592-1-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 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 --- v3: - Fixup typos in commit message v2: - Remove custom property 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);