Watchdog: DA9052/53 PMIC watchdog support (664a0d78) · Commits · e / devices / android_kernel_sony_msm8998

Documentation/watchdog/watchdog-parameters.txt

+5 −0

Original line number	Diff line number	Diff line
		@@ -78,6 +78,11 @@ wd0_timeout: Default watchdog0 timeout in 1/10secs
		wd1_timeout: Default watchdog1 timeout in 1/10secs
		wd2_timeout: Default watchdog2 timeout in 1/10secs
		-------------------------------------------------
		da9052wdt:
		timeout: Watchdog timeout in seconds. 2<= timeout <=131, default=2.048s
		nowayout: Watchdog cannot be stopped once started
		(default=kernel config parameter)
		-------------------------------------------------
		davinci_wdt:
		heartbeat: Watchdog heartbeat period in seconds from 1 to 600, default 60
		-------------------------------------------------

drivers/watchdog/Kconfig

+12 −0

Original line number	Diff line number	Diff line
		@@ -64,6 +64,18 @@ config SOFT_WATCHDOG
		To compile this driver as a module, choose M here: the
		module will be called softdog.

		config DA9052_WATCHDOG
		tristate "Dialog DA9052 Watchdog"
		depends on PMIC_DA9052
		select WATCHDOG_CORE
		help
		Support for the watchdog in the DA9052 PMIC. Watchdog trigger
		cause system reset.

		Say Y here to include support for the DA9052 watchdog.
		Alternatively say M to compile the driver as a module,
		which will be called da9052_wdt.

		config WM831X_WATCHDOG
		tristate "WM831x watchdog"
		depends on MFD_WM831X

drivers/watchdog/Makefile

+1 −0

Original line number	Diff line number	Diff line
		@@ -163,6 +163,7 @@ obj-$(CONFIG_WATCHDOG_CP1XXX) += cpwd.o
		obj-$(CONFIG_XEN_WDT) += xen_wdt.o

		# Architecture Independent
		obj-$(CONFIG_DA9052_WATCHDOG) += da9052_wdt.o
		obj-$(CONFIG_WM831X_WATCHDOG) += wm831x_wdt.o
		obj-$(CONFIG_WM8350_WATCHDOG) += wm8350_wdt.o
		obj-$(CONFIG_MAX63XX_WATCHDOG) += max63xx_wdt.o

drivers/watchdog/da9052_wdt.c

0 → 100644

+251 −0

Original line number	Diff line number	Diff line
		/*
		* System monitoring driver for DA9052 PMICs.
		*
		* Copyright(c) 2012 Dialog Semiconductor Ltd.
		*
		* Author: Anthony Olech <Anthony.Olech@diasemi.com>
		*
		* This program is free software; you can redistribute it and/or modify
		* it under the terms of the GNU General Public License as published by
		* the Free Software Foundation; either version 2 of the License, or
		* (at your option) any later version.
		*
		*/

		#include <linux/module.h>
		#include <linux/delay.h>
		#include <linux/uaccess.h>
		#include <linux/platform_device.h>
		#include <linux/time.h>
		#include <linux/watchdog.h>
		#include <linux/types.h>
		#include <linux/kernel.h>
		#include <linux/jiffies.h>
		#include <linux/delay.h>

		#include <linux/mfd/da9052/reg.h>
		#include <linux/mfd/da9052/da9052.h>

		#define DA9052_DEF_TIMEOUT 4
		#define DA9052_TWDMIN 256

		struct da9052_wdt_data {
		struct watchdog_device wdt;
		struct da9052 *da9052;
		struct kref kref;
		unsigned long jpast;
		};

		static const struct {
		u8 reg_val;
		int time; /* Seconds */
		} da9052_wdt_maps[] = {
		{ 1, 2 },
		{ 2, 4 },
		{ 3, 8 },
		{ 4, 16 },
		{ 5, 32 },
		{ 5, 33 }, /* Actual time 32.768s so included both 32s and 33s */
		{ 6, 65 },
		{ 6, 66 }, /* Actual time 65.536s so include both, 65s and 66s */
		{ 7, 131 },
		};


		static void da9052_wdt_release_resources(struct kref *r)
		{
		struct da9052_wdt_data *driver_data =
		container_of(r, struct da9052_wdt_data, kref);

		kfree(driver_data);
		}

		static int da9052_wdt_set_timeout(struct watchdog_device *wdt_dev,
		unsigned int timeout)
		{
		struct da9052_wdt_data *driver_data = watchdog_get_drvdata(wdt_dev);
		struct da9052 *da9052 = driver_data->da9052;
		int ret, i;

		/*
		* Disable the Watchdog timer before setting
		* new time out.
		*/
		ret = da9052_reg_update(da9052, DA9052_CONTROL_D_REG,
		DA9052_CONTROLD_TWDSCALE, 0);
		if (ret < 0) {
		dev_err(da9052->dev, "Failed to disable watchdog bit, %d\n",
		ret);
		return ret;
		}
		if (timeout) {
		/*
		* To change the timeout, da9052 needs to
		* be disabled for at least 150 us.
		*/
		udelay(150);

		/* Set the desired timeout */
		for (i = 0; i < ARRAY_SIZE(da9052_wdt_maps); i++)
		if (da9052_wdt_maps[i].time == timeout)
		break;

		if (i == ARRAY_SIZE(da9052_wdt_maps))
		ret = -EINVAL;
		else
		ret = da9052_reg_update(da9052, DA9052_CONTROL_D_REG,
		DA9052_CONTROLD_TWDSCALE,
		da9052_wdt_maps[i].reg_val);
		if (ret < 0) {
		dev_err(da9052->dev,
		"Failed to update timescale bit, %d\n", ret);
		return ret;
		}

		wdt_dev->timeout = timeout;
		driver_data->jpast = jiffies;
		}

		return 0;
		}

		static void da9052_wdt_ref(struct watchdog_device *wdt_dev)
		{
		struct da9052_wdt_data *driver_data = watchdog_get_drvdata(wdt_dev);

		kref_get(&driver_data->kref);
		}

		static void da9052_wdt_unref(struct watchdog_device *wdt_dev)
		{
		struct da9052_wdt_data *driver_data = watchdog_get_drvdata(wdt_dev);

		kref_put(&driver_data->kref, da9052_wdt_release_resources);
		}

		static int da9052_wdt_start(struct watchdog_device *wdt_dev)
		{
		return da9052_wdt_set_timeout(wdt_dev, wdt_dev->timeout);
		}

		static int da9052_wdt_stop(struct watchdog_device *wdt_dev)
		{
		return da9052_wdt_set_timeout(wdt_dev, 0);
		}

		static int da9052_wdt_ping(struct watchdog_device *wdt_dev)
		{
		struct da9052_wdt_data *driver_data = watchdog_get_drvdata(wdt_dev);
		struct da9052 *da9052 = driver_data->da9052;
		unsigned long msec, jnow = jiffies;
		int ret;

		/*
		* We have a minimum time for watchdog window called TWDMIN. A write
		* to the watchdog before this elapsed time should cause an error.
		*/
		msec = (jnow - driver_data->jpast) * 1000/HZ;
		if (msec < DA9052_TWDMIN)
		mdelay(msec);

		/* Reset the watchdog timer */
		ret = da9052_reg_update(da9052, DA9052_CONTROL_D_REG,
		DA9052_CONTROLD_WATCHDOG, 1 << 7);
		if (ret < 0)
		goto err_strobe;

		/*
		* FIXME: Reset the watchdog core, in general PMIC
		* is supposed to do this
		*/
		ret = da9052_reg_update(da9052, DA9052_CONTROL_D_REG,
		DA9052_CONTROLD_WATCHDOG, 0 << 7);
		err_strobe:
		return ret;
		}

		static struct watchdog_info da9052_wdt_info = {
		.options = WDIOF_SETTIMEOUT \| WDIOF_KEEPALIVEPING,
		.identity = "DA9052 Watchdog",
		};

		static const struct watchdog_ops da9052_wdt_ops = {
		.owner = THIS_MODULE,
		.start = da9052_wdt_start,
		.stop = da9052_wdt_stop,
		.ping = da9052_wdt_ping,
		.set_timeout = da9052_wdt_set_timeout,
		.ref = da9052_wdt_ref,
		.unref = da9052_wdt_unref,
		};


		static int __devinit da9052_wdt_probe(struct platform_device *pdev)
		{
		struct da9052 *da9052 = dev_get_drvdata(pdev->dev.parent);
		struct da9052_wdt_data *driver_data;
		struct watchdog_device *da9052_wdt;
		int ret;

		driver_data = devm_kzalloc(&pdev->dev, sizeof(*driver_data),
		GFP_KERNEL);
		if (!driver_data) {
		dev_err(da9052->dev, "Unable to alloacate watchdog device\n");
		ret = -ENOMEM;
		goto err;
		}
		driver_data->da9052 = da9052;

		da9052_wdt = &driver_data->wdt;

		da9052_wdt->timeout = DA9052_DEF_TIMEOUT;
		da9052_wdt->info = &da9052_wdt_info;
		da9052_wdt->ops = &da9052_wdt_ops;
		watchdog_set_drvdata(da9052_wdt, driver_data);

		kref_init(&driver_data->kref);

		ret = da9052_reg_update(da9052, DA9052_CONTROL_D_REG,
		DA9052_CONTROLD_TWDSCALE, 0);
		if (ret < 0) {
		dev_err(&pdev->dev, "Failed to disable watchdog bits, %d\n",
		ret);
		goto err;
		}

		ret = watchdog_register_device(&driver_data->wdt);
		if (ret != 0) {
		dev_err(da9052->dev, "watchdog_register_device() failed: %d\n",
		ret);
		goto err;
		}

		dev_set_drvdata(&pdev->dev, driver_data);
		err:
		return ret;
		}

		static int __devexit da9052_wdt_remove(struct platform_device *pdev)
		{
		struct da9052_wdt_data *driver_data = dev_get_drvdata(&pdev->dev);

		watchdog_unregister_device(&driver_data->wdt);
		kref_put(&driver_data->kref, da9052_wdt_release_resources);

		return 0;
		}

		static struct platform_driver da9052_wdt_driver = {
		.probe = da9052_wdt_probe,
		.remove = __devexit_p(da9052_wdt_remove),
		.driver = {
		.name = "da9052-watchdog",
		},
		};

		module_platform_driver(da9052_wdt_driver);

		MODULE_AUTHOR("Anthony Olech <Anthony.Olech@diasemi.com>");
		MODULE_DESCRIPTION("DA9052 SM Device Driver");
		MODULE_LICENSE("GPL");
		MODULE_ALIAS("platform:da9052-watchdog");