watchdog: introduce retu_wdt driver (3d3a6d18) · Commits · e / devices / android_kernel_samsung_universal8890

drivers/watchdog/Kconfig

+12 −0

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		@@ -377,6 +377,18 @@ config UX500_WATCHDOG
		To compile this driver as a module, choose M here: the
		module will be called ux500_wdt.

		config RETU_WATCHDOG
		tristate "Retu watchdog"
		depends on MFD_RETU
		select WATCHDOG_CORE
		help
		Retu watchdog driver for Nokia Internet Tablets (770, N800,
		N810). At least on N800 the watchdog cannot be disabled, so
		this driver is essential and you should enable it.

		To compile this driver as a module, choose M here: the
		module will be called retu_wdt.

		# AVR32 Architecture

		config AT32AP700X_WDT

drivers/watchdog/Makefile

+1 −0

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		@@ -53,6 +53,7 @@ obj-$(CONFIG_NUC900_WATCHDOG) += nuc900_wdt.o
		obj-$(CONFIG_TS72XX_WATCHDOG) += ts72xx_wdt.o
		obj-$(CONFIG_IMX2_WDT) += imx2_wdt.o
		obj-$(CONFIG_UX500_WATCHDOG) += ux500_wdt.o
		obj-$(CONFIG_RETU_WATCHDOG) += retu_wdt.o

		# AVR32 Architecture
		obj-$(CONFIG_AT32AP700X_WDT) += at32ap700x_wdt.o

drivers/watchdog/retu_wdt.c

0 → 100644

+178 −0

Original line number	Diff line number	Diff line
		/*
		* Retu watchdog driver
		*
		* Copyright (C) 2004, 2005 Nokia Corporation
		*
		* Based on code written by Amit Kucheria and Michael Buesch.
		* Rewritten by Aaro Koskinen.
		*
		* This file is subject to the terms and conditions of the GNU General
		* Public License. See the file "COPYING" in the main directory of this
		* archive for more details.
		*
		* This program is distributed in the hope that it will be useful,
		* but WITHOUT ANY WARRANTY; without even the implied warranty of
		* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
		* GNU General Public License for more details.
		*/

		#include <linux/init.h>
		#include <linux/slab.h>
		#include <linux/errno.h>
		#include <linux/device.h>
		#include <linux/kernel.h>
		#include <linux/module.h>
		#include <linux/mfd/retu.h>
		#include <linux/watchdog.h>
		#include <linux/platform_device.h>

		/* Watchdog timer values in seconds */
		#define RETU_WDT_MAX_TIMER 63

		struct retu_wdt_dev {
		struct retu_dev *rdev;
		struct device *dev;
		struct delayed_work ping_work;
		};

		/*
		* Since Retu watchdog cannot be disabled in hardware, we must kick it
		* with a timer until userspace watchdog software takes over. If
		* CONFIG_WATCHDOG_NOWAYOUT is set, we never start the feeding.
		*/
		static void retu_wdt_ping_enable(struct retu_wdt_dev *wdev)
		{
		retu_write(wdev->rdev, RETU_REG_WATCHDOG, RETU_WDT_MAX_TIMER);
		schedule_delayed_work(&wdev->ping_work,
		round_jiffies_relative(RETU_WDT_MAX_TIMER * HZ / 2));
		}

		static void retu_wdt_ping_disable(struct retu_wdt_dev *wdev)
		{
		retu_write(wdev->rdev, RETU_REG_WATCHDOG, RETU_WDT_MAX_TIMER);
		cancel_delayed_work_sync(&wdev->ping_work);
		}

		static void retu_wdt_ping_work(struct work_struct *work)
		{
		struct retu_wdt_dev *wdev = container_of(to_delayed_work(work),
		struct retu_wdt_dev, ping_work);
		retu_wdt_ping_enable(wdev);
		}

		static int retu_wdt_start(struct watchdog_device *wdog)
		{
		struct retu_wdt_dev *wdev = watchdog_get_drvdata(wdog);

		retu_wdt_ping_disable(wdev);

		return retu_write(wdev->rdev, RETU_REG_WATCHDOG, wdog->timeout);
		}

		static int retu_wdt_stop(struct watchdog_device *wdog)
		{
		struct retu_wdt_dev *wdev = watchdog_get_drvdata(wdog);

		retu_wdt_ping_enable(wdev);

		return 0;
		}

		static int retu_wdt_ping(struct watchdog_device *wdog)
		{
		struct retu_wdt_dev *wdev = watchdog_get_drvdata(wdog);

		return retu_write(wdev->rdev, RETU_REG_WATCHDOG, wdog->timeout);
		}

		static int retu_wdt_set_timeout(struct watchdog_device *wdog,
		unsigned int timeout)
		{
		struct retu_wdt_dev *wdev = watchdog_get_drvdata(wdog);

		wdog->timeout = timeout;
		return retu_write(wdev->rdev, RETU_REG_WATCHDOG, wdog->timeout);
		}

		static const struct watchdog_info retu_wdt_info = {
		.options = WDIOF_SETTIMEOUT \| WDIOF_KEEPALIVEPING,
		.identity = "Retu watchdog",
		};

		static const struct watchdog_ops retu_wdt_ops = {
		.owner = THIS_MODULE,
		.start = retu_wdt_start,
		.stop = retu_wdt_stop,
		.ping = retu_wdt_ping,
		.set_timeout = retu_wdt_set_timeout,
		};

		static int retu_wdt_probe(struct platform_device *pdev)
		{
		struct retu_dev *rdev = dev_get_drvdata(pdev->dev.parent);
		bool nowayout = WATCHDOG_NOWAYOUT;
		struct watchdog_device *retu_wdt;
		struct retu_wdt_dev *wdev;
		int ret;

		retu_wdt = devm_kzalloc(&pdev->dev, sizeof(*retu_wdt), GFP_KERNEL);
		if (!retu_wdt)
		return -ENOMEM;

		wdev = devm_kzalloc(&pdev->dev, sizeof(*wdev), GFP_KERNEL);
		if (!wdev)
		return -ENOMEM;

		retu_wdt->info = &retu_wdt_info;
		retu_wdt->ops = &retu_wdt_ops;
		retu_wdt->timeout = RETU_WDT_MAX_TIMER;
		retu_wdt->min_timeout = 0;
		retu_wdt->max_timeout = RETU_WDT_MAX_TIMER;

		watchdog_set_drvdata(retu_wdt, wdev);
		watchdog_set_nowayout(retu_wdt, nowayout);

		wdev->rdev = rdev;
		wdev->dev = &pdev->dev;

		INIT_DELAYED_WORK(&wdev->ping_work, retu_wdt_ping_work);

		ret = watchdog_register_device(retu_wdt);
		if (ret < 0)
		return ret;

		if (nowayout)
		retu_wdt_ping(retu_wdt);
		else
		retu_wdt_ping_enable(wdev);

		platform_set_drvdata(pdev, retu_wdt);

		return 0;
		}

		static int retu_wdt_remove(struct platform_device *pdev)
		{
		struct watchdog_device *wdog = platform_get_drvdata(pdev);
		struct retu_wdt_dev *wdev = watchdog_get_drvdata(wdog);

		watchdog_unregister_device(wdog);
		cancel_delayed_work_sync(&wdev->ping_work);

		return 0;
		}

		static struct platform_driver retu_wdt_driver = {
		.probe = retu_wdt_probe,
		.remove = retu_wdt_remove,
		.driver = {
		.name = "retu-wdt",
		},
		};
		module_platform_driver(retu_wdt_driver);

		MODULE_ALIAS("platform:retu-wdt");
		MODULE_DESCRIPTION("Retu watchdog");
		MODULE_AUTHOR("Amit Kucheria");
		MODULE_AUTHOR("Aaro Koskinen <aaro.koskinen@iki.fi>");
		MODULE_LICENSE("GPL");