watchdog: da9062: DA9062 watchdog driver (7a7cb009) · Commits · e / devices / android_kernel_oneplus_sm8150

drivers/watchdog/Kconfig

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Original line number	Diff line number	Diff line
		@@ -96,6 +96,15 @@ config DA9063_WATCHDOG

		This driver can be built as a module. The module name is da9063_wdt.

		config DA9062_WATCHDOG
		tristate "Dialog DA9062 Watchdog"
		depends on MFD_DA9062
		select WATCHDOG_CORE
		help
		Support for the watchdog in the DA9062 PMIC.

		This driver can be built as a module. The module name is da9062_wdt.

		config GPIO_WATCHDOG
		tristate "Watchdog device controlled through GPIO-line"
		depends on OF_GPIO

drivers/watchdog/Makefile

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Original line number	Diff line number	Diff line
		@@ -181,6 +181,7 @@ obj-$(CONFIG_XEN_WDT) += xen_wdt.o
		# Architecture Independent
		obj-$(CONFIG_DA9052_WATCHDOG) += da9052_wdt.o
		obj-$(CONFIG_DA9055_WATCHDOG) += da9055_wdt.o
		obj-$(CONFIG_DA9062_WATCHDOG) += da9062_wdt.o
		obj-$(CONFIG_DA9063_WATCHDOG) += da9063_wdt.o
		obj-$(CONFIG_GPIO_WATCHDOG) += gpio_wdt.o
		obj-$(CONFIG_WM831X_WATCHDOG) += wm831x_wdt.o

drivers/watchdog/da9062_wdt.c

0 → 100644

+253 −0

Original line number	Diff line number	Diff line
		/*
		* da9062_wdt.c - WDT device driver for DA9062
		* Copyright (C) 2015 Dialog Semiconductor Ltd.
		*
		* 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.
		*
		* 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/kernel.h>
		#include <linux/module.h>
		#include <linux/watchdog.h>
		#include <linux/platform_device.h>
		#include <linux/uaccess.h>
		#include <linux/slab.h>
		#include <linux/delay.h>
		#include <linux/jiffies.h>
		#include <linux/mfd/da9062/registers.h>
		#include <linux/mfd/da9062/core.h>
		#include <linux/regmap.h>
		#include <linux/of.h>

		static const unsigned int wdt_timeout[] = { 0, 2, 4, 8, 16, 32, 65, 131 };
		#define DA9062_TWDSCALE_DISABLE 0
		#define DA9062_TWDSCALE_MIN 1
		#define DA9062_TWDSCALE_MAX (ARRAY_SIZE(wdt_timeout) - 1)
		#define DA9062_WDT_MIN_TIMEOUT wdt_timeout[DA9062_TWDSCALE_MIN]
		#define DA9062_WDT_MAX_TIMEOUT wdt_timeout[DA9062_TWDSCALE_MAX]
		#define DA9062_WDG_DEFAULT_TIMEOUT wdt_timeout[DA9062_TWDSCALE_MAX-1]
		#define DA9062_RESET_PROTECTION_MS 300

		struct da9062_watchdog {
		struct da9062 *hw;
		struct watchdog_device wdtdev;
		unsigned long j_time_stamp;
		};

		static void da9062_set_window_start(struct da9062_watchdog *wdt)
		{
		wdt->j_time_stamp = jiffies;
		}

		static void da9062_apply_window_protection(struct da9062_watchdog *wdt)
		{
		unsigned long delay = msecs_to_jiffies(DA9062_RESET_PROTECTION_MS);
		unsigned long timeout = wdt->j_time_stamp + delay;
		unsigned long now = jiffies;
		unsigned int diff_ms;

		/* if time-limit has not elapsed then wait for remainder */
		if (time_before(now, timeout)) {
		diff_ms = jiffies_to_msecs(timeout-now);
		dev_dbg(wdt->hw->dev,
		"Kicked too quickly. Delaying %u msecs\n", diff_ms);
		msleep(diff_ms);
		}
		}

		static unsigned int da9062_wdt_timeout_to_sel(unsigned int secs)
		{
		unsigned int i;

		for (i = DA9062_TWDSCALE_MIN; i <= DA9062_TWDSCALE_MAX; i++) {
		if (wdt_timeout[i] >= secs)
		return i;
		}

		return DA9062_TWDSCALE_MAX;
		}

		static int da9062_reset_watchdog_timer(struct da9062_watchdog *wdt)
		{
		int ret;

		da9062_apply_window_protection(wdt);

		ret = regmap_update_bits(wdt->hw->regmap,
		DA9062AA_CONTROL_F,
		DA9062AA_WATCHDOG_MASK,
		DA9062AA_WATCHDOG_MASK);

		da9062_set_window_start(wdt);

		return ret;
		}

		static int da9062_wdt_update_timeout_register(struct da9062_watchdog *wdt,
		unsigned int regval)
		{
		struct da9062 *chip = wdt->hw;
		int ret;

		ret = da9062_reset_watchdog_timer(wdt);
		if (ret)
		return ret;

		return regmap_update_bits(chip->regmap,
		DA9062AA_CONTROL_D,
		DA9062AA_TWDSCALE_MASK,
		regval);
		}

		static int da9062_wdt_start(struct watchdog_device *wdd)
		{
		struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd);
		unsigned int selector;
		int ret;

		selector = da9062_wdt_timeout_to_sel(wdt->wdtdev.timeout);
		ret = da9062_wdt_update_timeout_register(wdt, selector);
		if (ret)
		dev_err(wdt->hw->dev, "Watchdog failed to start (err = %d)\n",
		ret);

		return ret;
		}

		static int da9062_wdt_stop(struct watchdog_device *wdd)
		{
		struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd);
		int ret;

		ret = da9062_reset_watchdog_timer(wdt);
		if (ret) {
		dev_err(wdt->hw->dev, "Failed to ping the watchdog (err = %d)\n",
		ret);
		return ret;
		}

		ret = regmap_update_bits(wdt->hw->regmap,
		DA9062AA_CONTROL_D,
		DA9062AA_TWDSCALE_MASK,
		DA9062_TWDSCALE_DISABLE);
		if (ret)
		dev_err(wdt->hw->dev, "Watchdog failed to stop (err = %d)\n",
		ret);

		return ret;
		}

		static int da9062_wdt_ping(struct watchdog_device *wdd)
		{
		struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd);
		int ret;

		ret = da9062_reset_watchdog_timer(wdt);
		if (ret)
		dev_err(wdt->hw->dev, "Failed to ping the watchdog (err = %d)\n",
		ret);

		return ret;
		}

		static int da9062_wdt_set_timeout(struct watchdog_device *wdd,
		unsigned int timeout)
		{
		struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd);
		unsigned int selector;
		int ret;

		selector = da9062_wdt_timeout_to_sel(timeout);
		ret = da9062_wdt_update_timeout_register(wdt, selector);
		if (ret)
		dev_err(wdt->hw->dev, "Failed to set watchdog timeout (err = %d)\n",
		ret);
		else
		wdd->timeout = wdt_timeout[selector];

		return ret;
		}

		static const struct watchdog_info da9062_watchdog_info = {
		.options = WDIOF_SETTIMEOUT \| WDIOF_KEEPALIVEPING,
		.identity = "DA9062 WDT",
		};

		static const struct watchdog_ops da9062_watchdog_ops = {
		.owner = THIS_MODULE,
		.start = da9062_wdt_start,
		.stop = da9062_wdt_stop,
		.ping = da9062_wdt_ping,
		.set_timeout = da9062_wdt_set_timeout,
		};

		static int da9062_wdt_probe(struct platform_device *pdev)
		{
		int ret;
		struct da9062 *chip;
		struct da9062_watchdog *wdt;

		chip = dev_get_drvdata(pdev->dev.parent);
		if (!chip)
		return -EINVAL;

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

		wdt->hw = chip;

		wdt->wdtdev.info = &da9062_watchdog_info;
		wdt->wdtdev.ops = &da9062_watchdog_ops;
		wdt->wdtdev.min_timeout = DA9062_WDT_MIN_TIMEOUT;
		wdt->wdtdev.max_timeout = DA9062_WDT_MAX_TIMEOUT;
		wdt->wdtdev.timeout = DA9062_WDG_DEFAULT_TIMEOUT;
		wdt->wdtdev.status = WATCHDOG_NOWAYOUT_INIT_STATUS;

		watchdog_set_drvdata(&wdt->wdtdev, wdt);
		dev_set_drvdata(&pdev->dev, wdt);

		ret = watchdog_register_device(&wdt->wdtdev);
		if (ret < 0) {
		dev_err(wdt->hw->dev,
		"watchdog registration failed (%d)\n", ret);
		return ret;
		}

		da9062_set_window_start(wdt);

		ret = da9062_wdt_ping(&wdt->wdtdev);
		if (ret < 0)
		watchdog_unregister_device(&wdt->wdtdev);

		return ret;
		}

		static int da9062_wdt_remove(struct platform_device *pdev)
		{
		struct da9062_watchdog *wdt = dev_get_drvdata(&pdev->dev);

		watchdog_unregister_device(&wdt->wdtdev);
		return 0;
		}

		static struct platform_driver da9062_wdt_driver = {
		.probe = da9062_wdt_probe,
		.remove = da9062_wdt_remove,
		.driver = {
		.name = "da9062-watchdog",
		},
		};
		module_platform_driver(da9062_wdt_driver);

		MODULE_AUTHOR("S Twiss <stwiss.opensource@diasemi.com>");
		MODULE_DESCRIPTION("WDT device driver for Dialog DA9062");
		MODULE_LICENSE("GPL");
		MODULE_ALIAS("platform:da9062-watchdog");