From patchwork Thu Aug 13 12:48:24 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michael Walle X-Patchwork-Id: 11712465 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 88BDC722 for ; Thu, 13 Aug 2020 12:49:53 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 53A0420791 for ; Thu, 13 Aug 2020 12:49:53 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="BTAq5PFk"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=walle.cc header.i=@walle.cc header.b="Z6fKIi+7" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 53A0420791 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=walle.cc Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To:Message-Id:Date: Subject:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=kJs4dCyFYWZGPzWJdzdlkE/uNizRFIUFxm8rEdttVHs=; b=BTAq5PFke0cBBSRyw2OR4f/8W KKFPRPF/bpyeKmOiCrdqIfhOc5tEwdhiiL+O+iPxlDdVI3RpJI8SIdq11VFFngcPXPUh6HiKThZEM APyuYuCBJLMCc1+GzvKxflco8jSZLAZH3B1o0C8s22Jd8uxaQeOA61qaNnxnAz1aoCldF0aQsf1GQ aJl8+5w1BPARNZA/QEoOnBvtflFBf1C2aJni/Cx02FyAagbmH4g2luyYgCuDY4p/AMQSptwAY28M8 sQhGsiSiLh4UXuLJOtOC2wmNoza0gNyTcO8tPTT7ySwt6vqqBLsOYeuPv3dDg72fSojoWqbdTpXcZ dZ+WgSSBg==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1k6Cft-0004fk-9U; Thu, 13 Aug 2020 12:49:41 +0000 Received: from ssl.serverraum.org ([176.9.125.105]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1k6CfA-0004QC-HR for linux-arm-kernel@lists.infradead.org; Thu, 13 Aug 2020 12:49:04 +0000 Received: from mwalle01.sab.local. (unknown [213.135.10.150]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-384) server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by ssl.serverraum.org (Postfix) with ESMTPSA id 208E923E44; Thu, 13 Aug 2020 14:48:51 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=walle.cc; s=mail2016061301; t=1597322931; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=uCVdYm8TKc6zhR07RFPNiC/0PSVOyHldVAui8d25PnU=; b=Z6fKIi+7xN7rvqH1Qh0dlaJCSaQR9quw+xG3t7w6HtUCJiqObNeCcPn++3Y4YCplIYbuF2 19EAMYUO2ioYW2Yl5SPbRJKy03/P2nWxR8QVt5eBZj4RifRogIRpsn5NgsPc+TjyXcG+t4 EGprw/c/JYxEnJk/+mk7yTEitiitc5s= From: Michael Walle To: linux-gpio@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-hwmon@vger.kernel.org, linux-pwm@vger.kernel.org, linux-watchdog@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: [PATCH v8 05/13] watchdog: add support for sl28cpld watchdog Date: Thu, 13 Aug 2020 14:48:24 +0200 Message-Id: <20200813124832.17349-6-michael@walle.cc> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200813124832.17349-1-michael@walle.cc> References: <20200813124832.17349-1-michael@walle.cc> MIME-Version: 1.0 X-Spam: Yes X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200813_084856_888506_DC11F00A X-CRM114-Status: GOOD ( 31.67 ) X-Spam-Score: -2.5 (--) X-Spam-Report: SpamAssassin version 3.4.4 on merlin.infradead.org summary: Content analysis details: (-2.5 points) pts rule name description ---- ---------------------- -------------------------------------------------- -2.3 RCVD_IN_DNSWL_MED RBL: Sender listed at https://www.dnswl.org/, medium trust [176.9.125.105 listed in list.dnswl.org] 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record -0.0 SPF_PASS SPF: sender matches SPF record -0.1 DKIM_VALID_AU Message has a valid DKIM or DK signature from author's domain 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily valid -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature -0.1 DKIM_VALID_EF Message has a valid DKIM or DK signature from envelope-from domain X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Marc Zyngier , Jean Delvare , Catalin Marinas , Jason Cooper , Will Deacon , Greg Kroah-Hartman , Shawn Guo , Linus Walleij , Andy Shevchenko , Li Yang , Bartosz Golaszewski , Michael Walle , Rob Herring , Thierry Reding , Mark Brown , Pavel Machek , =?utf-8?q?Uwe_Kleine-K=C3=B6nig?= , Thomas Gleixner , Wim Van Sebroeck , Lee Jones , Guenter Roeck Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org Add support for the watchdog of the sl28cpld board management controller. This is part of a multi-function device driver. Signed-off-by: Michael Walle Acked-by: Guenter Roeck --- Changes since v7: - added "depends on MFD_SL28CPLD || COMPILE_TEST" Changes since v6: - none Changes since v5: - none Changes since v4: - update copyright year - remove #include , suggested by Andy. - slightly reworked the error code handling (only style), suggested by Andy. - Don't use "if (ret < 0)", but only "if (ret)", suggested by Andy. - remove comma in terminator line of the compatible strings list - don't use KBUID_MODNAME - remove the platform device table Changes since v3: - see cover letter drivers/watchdog/Kconfig | 11 ++ drivers/watchdog/Makefile | 1 + drivers/watchdog/sl28cpld_wdt.c | 229 ++++++++++++++++++++++++++++++++ 3 files changed, 241 insertions(+) create mode 100644 drivers/watchdog/sl28cpld_wdt.c diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index ab7aad5a1e69..ba698340ed6f 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -340,6 +340,17 @@ config MLX_WDT To compile this driver as a module, choose M here: the module will be called mlx-wdt. +config SL28CPLD_WATCHDOG + tristate "Kontron sl28cpld Watchdog" + depends on MFD_SL28CPLD || COMPILE_TEST + select WATCHDOG_CORE + help + Say Y here to include support for the watchdog timer + on the Kontron sl28 CPLD. + + To compile this driver as a module, choose M here: the + module will be called sl28cpld_wdt. + # ALPHA Architecture # ARM Architecture diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile index 97bed1d3d97c..aa6e41126901 100644 --- a/drivers/watchdog/Makefile +++ b/drivers/watchdog/Makefile @@ -225,3 +225,4 @@ obj-$(CONFIG_MENF21BMC_WATCHDOG) += menf21bmc_wdt.o obj-$(CONFIG_MENZ069_WATCHDOG) += menz69_wdt.o obj-$(CONFIG_RAVE_SP_WATCHDOG) += rave-sp-wdt.o obj-$(CONFIG_STPMIC1_WATCHDOG) += stpmic1_wdt.o +obj-$(CONFIG_SL28CPLD_WATCHDOG) += sl28cpld_wdt.o diff --git a/drivers/watchdog/sl28cpld_wdt.c b/drivers/watchdog/sl28cpld_wdt.c new file mode 100644 index 000000000000..a45047d8d9ab --- /dev/null +++ b/drivers/watchdog/sl28cpld_wdt.c @@ -0,0 +1,229 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * sl28cpld watchdog driver + * + * Copyright 2020 Kontron Europe GmbH + */ + +#include +#include +#include +#include +#include +#include +#include + +/* + * Watchdog timer block registers. + */ +#define WDT_CTRL 0x00 +#define WDT_CTRL_EN BIT(0) +#define WDT_CTRL_LOCK BIT(2) +#define WDT_CTRL_ASSERT_SYS_RESET BIT(6) +#define WDT_CTRL_ASSERT_WDT_TIMEOUT BIT(7) +#define WDT_TIMEOUT 0x01 +#define WDT_KICK 0x02 +#define WDT_KICK_VALUE 0x6b +#define WDT_COUNT 0x03 + +#define WDT_DEFAULT_TIMEOUT 10 + +static bool nowayout = WATCHDOG_NOWAYOUT; +module_param(nowayout, bool, 0); +MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" + __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); + +static int timeout; +module_param(timeout, int, 0); +MODULE_PARM_DESC(timeout, "Initial watchdog timeout in seconds"); + +struct sl28cpld_wdt { + struct watchdog_device wdd; + struct regmap *regmap; + u32 offset; + bool assert_wdt_timeout; +}; + +static int sl28cpld_wdt_ping(struct watchdog_device *wdd) +{ + struct sl28cpld_wdt *wdt = watchdog_get_drvdata(wdd); + + return regmap_write(wdt->regmap, wdt->offset + WDT_KICK, + WDT_KICK_VALUE); +} + +static int sl28cpld_wdt_start(struct watchdog_device *wdd) +{ + struct sl28cpld_wdt *wdt = watchdog_get_drvdata(wdd); + unsigned int val; + + val = WDT_CTRL_EN | WDT_CTRL_ASSERT_SYS_RESET; + if (wdt->assert_wdt_timeout) + val |= WDT_CTRL_ASSERT_WDT_TIMEOUT; + if (nowayout) + val |= WDT_CTRL_LOCK; + + return regmap_update_bits(wdt->regmap, wdt->offset + WDT_CTRL, + val, val); +} + +static int sl28cpld_wdt_stop(struct watchdog_device *wdd) +{ + struct sl28cpld_wdt *wdt = watchdog_get_drvdata(wdd); + + return regmap_update_bits(wdt->regmap, wdt->offset + WDT_CTRL, + WDT_CTRL_EN, 0); +} + +static unsigned int sl28cpld_wdt_get_timeleft(struct watchdog_device *wdd) +{ + struct sl28cpld_wdt *wdt = watchdog_get_drvdata(wdd); + unsigned int val; + int ret; + + ret = regmap_read(wdt->regmap, wdt->offset + WDT_COUNT, &val); + if (ret) + return 0; + + return val; +} + +static int sl28cpld_wdt_set_timeout(struct watchdog_device *wdd, + unsigned int timeout) +{ + struct sl28cpld_wdt *wdt = watchdog_get_drvdata(wdd); + int ret; + + ret = regmap_write(wdt->regmap, wdt->offset + WDT_TIMEOUT, timeout); + if (ret) + return ret; + + wdd->timeout = timeout; + + return 0; +} + +static const struct watchdog_info sl28cpld_wdt_info = { + .options = WDIOF_MAGICCLOSE | WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING, + .identity = "sl28cpld watchdog", +}; + +static struct watchdog_ops sl28cpld_wdt_ops = { + .owner = THIS_MODULE, + .start = sl28cpld_wdt_start, + .stop = sl28cpld_wdt_stop, + .ping = sl28cpld_wdt_ping, + .set_timeout = sl28cpld_wdt_set_timeout, + .get_timeleft = sl28cpld_wdt_get_timeleft, +}; + +static int sl28cpld_wdt_probe(struct platform_device *pdev) +{ + struct watchdog_device *wdd; + struct sl28cpld_wdt *wdt; + unsigned int status; + unsigned int val; + int ret; + + if (!pdev->dev.parent) + return -ENODEV; + + wdt = devm_kzalloc(&pdev->dev, sizeof(*wdt), GFP_KERNEL); + if (!wdt) + return -ENOMEM; + + wdt->regmap = dev_get_regmap(pdev->dev.parent, NULL); + if (!wdt->regmap) + return -ENODEV; + + ret = device_property_read_u32(&pdev->dev, "reg", &wdt->offset); + if (ret) + return -EINVAL; + + wdt->assert_wdt_timeout = device_property_read_bool(&pdev->dev, + "kontron,assert-wdt-timeout-pin"); + + /* initialize struct watchdog_device */ + wdd = &wdt->wdd; + wdd->parent = &pdev->dev; + wdd->info = &sl28cpld_wdt_info; + wdd->ops = &sl28cpld_wdt_ops; + wdd->min_timeout = 1; + wdd->max_timeout = 255; + + watchdog_set_drvdata(wdd, wdt); + watchdog_stop_on_reboot(wdd); + + /* + * Read the status early, in case of an error, we haven't modified the + * hardware. + */ + ret = regmap_read(wdt->regmap, wdt->offset + WDT_CTRL, &status); + if (ret) + return ret; + + /* + * Initial timeout value, may be overwritten by device tree or module + * parmeter in watchdog_init_timeout(). + * + * Reading a zero here means that either the hardware has a default + * value of zero (which is very unlikely and definitely a hardware + * bug) or the bootloader set it to zero. In any case, we handle + * this case gracefully and set out own timeout. + */ + ret = regmap_read(wdt->regmap, wdt->offset + WDT_TIMEOUT, &val); + if (ret) + return ret; + + if (val) + wdd->timeout = val; + else + wdd->timeout = WDT_DEFAULT_TIMEOUT; + + watchdog_init_timeout(wdd, timeout, &pdev->dev); + sl28cpld_wdt_set_timeout(wdd, wdd->timeout); + + /* if the watchdog is locked, we set nowayout */ + if (status & WDT_CTRL_LOCK) + nowayout = true; + watchdog_set_nowayout(wdd, nowayout); + + /* + * If watchdog is already running, keep it enabled, but make + * sure its mode is set correctly. + */ + if (status & WDT_CTRL_EN) { + sl28cpld_wdt_start(wdd); + set_bit(WDOG_HW_RUNNING, &wdd->status); + } + + ret = devm_watchdog_register_device(&pdev->dev, wdd); + if (ret < 0) { + dev_err(&pdev->dev, "failed to register watchdog device\n"); + return ret; + } + + dev_info(&pdev->dev, "initial timeout %d sec%s\n", + wdd->timeout, nowayout ? ", nowayout" : ""); + + return 0; +} + +static const struct of_device_id sl28cpld_wdt_of_match[] = { + { .compatible = "kontron,sl28cpld-wdt" }, + {} +}; +MODULE_DEVICE_TABLE(of, sl28cpld_wdt_of_match); + +static struct platform_driver sl28cpld_wdt_driver = { + .probe = sl28cpld_wdt_probe, + .driver = { + .name = "sl28cpld-wdt", + .of_match_table = sl28cpld_wdt_of_match, + }, +}; +module_platform_driver(sl28cpld_wdt_driver); + +MODULE_DESCRIPTION("sl28cpld Watchdog Driver"); +MODULE_AUTHOR("Michael Walle "); +MODULE_LICENSE("GPL");