Contributors: 11
	  
        
          | Author | 
          Tokens | 
          Token Proportion | 
          Commits | 
          Commit Proportion | 
        
	  
	  
        
        
          | Krystian Garbaciak | 
          564 | 
          63.73% | 
          1 | 
          5.88% | 
        
        
          | Marco Felsch | 
          137 | 
          15.48% | 
          5 | 
          29.41% | 
        
        
          | Geert Uytterhoeven | 
          47 | 
          5.31% | 
          1 | 
          5.88% | 
        
        
          | Stefan Riedmueller | 
          30 | 
          3.39% | 
          1 | 
          5.88% | 
        
        
          | Wolfram Sang | 
          27 | 
          3.05% | 
          1 | 
          5.88% | 
        
        
          | Karsten Wiese | 
          26 | 
          2.94% | 
          1 | 
          5.88% | 
        
        
          | Guenter Roeck | 
          22 | 
          2.49% | 
          3 | 
          17.65% | 
        
        
          | Damien Riegel | 
          17 | 
          1.92% | 
          1 | 
          5.88% | 
        
        
          | Stefan Christ | 
          9 | 
          1.02% | 
          1 | 
          5.88% | 
        
        
          | Pratyush Anand | 
          4 | 
          0.45% | 
          1 | 
          5.88% | 
        
        
          | Marcus Folkesson | 
          2 | 
          0.23% | 
          1 | 
          5.88% | 
        
	  
	  
        
          | Total | 
          885 | 
           | 
          17 | 
           | 
	    
	  
    
 
// SPDX-License-Identifier: GPL-2.0+
/*
 * Watchdog driver for DA9063 PMICs.
 *
 * Copyright(c) 2012 Dialog Semiconductor Ltd.
 *
 * Author: Mariusz Wojtasik <mariusz.wojtasik@diasemi.com>
 *
 */
#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/mfd/da9063/registers.h>
#include <linux/mfd/da9063/core.h>
#include <linux/regmap.h>
/*
 * Watchdog selector to timeout in seconds.
 *   0: WDT disabled;
 *   others: timeout = 2048 ms * 2^(TWDSCALE-1).
 */
static const unsigned int wdt_timeout[] = { 0, 2, 4, 8, 16, 32, 65, 131 };
#define DA9063_TWDSCALE_DISABLE		0
#define DA9063_TWDSCALE_MIN		1
#define DA9063_TWDSCALE_MAX		(ARRAY_SIZE(wdt_timeout) - 1)
#define DA9063_WDT_MIN_TIMEOUT		wdt_timeout[DA9063_TWDSCALE_MIN]
#define DA9063_WDT_MAX_TIMEOUT		wdt_timeout[DA9063_TWDSCALE_MAX]
#define DA9063_WDG_TIMEOUT		wdt_timeout[3]
#define DA9063_RESET_PROTECTION_MS	256
static unsigned int da9063_wdt_timeout_to_sel(unsigned int secs)
{
	unsigned int i;
	for (i = DA9063_TWDSCALE_MIN; i <= DA9063_TWDSCALE_MAX; i++) {
		if (wdt_timeout[i] >= secs)
			return i;
	}
	return DA9063_TWDSCALE_MAX;
}
/*
 * Read the currently active timeout.
 * Zero means the watchdog is disabled.
 */
static unsigned int da9063_wdt_read_timeout(struct da9063 *da9063)
{
	unsigned int val;
	regmap_read(da9063->regmap, DA9063_REG_CONTROL_D, &val);
	return wdt_timeout[val & DA9063_TWDSCALE_MASK];
}
static int da9063_wdt_disable_timer(struct da9063 *da9063)
{
	return regmap_update_bits(da9063->regmap, DA9063_REG_CONTROL_D,
				  DA9063_TWDSCALE_MASK,
				  DA9063_TWDSCALE_DISABLE);
}
static int
da9063_wdt_update_timeout(struct da9063 *da9063, unsigned int timeout)
{
	unsigned int regval;
	int ret;
	/*
	 * The watchdog triggers a reboot if a timeout value is already
	 * programmed because the timeout value combines two functions
	 * in one: indicating the counter limit and starting the watchdog.
	 * The watchdog must be disabled to be able to change the timeout
	 * value if the watchdog is already running. Then we can set the
	 * new timeout value which enables the watchdog again.
	 */
	ret = da9063_wdt_disable_timer(da9063);
	if (ret)
		return ret;
	usleep_range(150, 300);
	regval = da9063_wdt_timeout_to_sel(timeout);
	return regmap_update_bits(da9063->regmap, DA9063_REG_CONTROL_D,
				  DA9063_TWDSCALE_MASK, regval);
}
static int da9063_wdt_start(struct watchdog_device *wdd)
{
	struct da9063 *da9063 = watchdog_get_drvdata(wdd);
	int ret;
	ret = da9063_wdt_update_timeout(da9063, wdd->timeout);
	if (ret)
		dev_err(da9063->dev, "Watchdog failed to start (err = %d)\n",
			ret);
	return ret;
}
static int da9063_wdt_stop(struct watchdog_device *wdd)
{
	struct da9063 *da9063 = watchdog_get_drvdata(wdd);
	int ret;
	ret = da9063_wdt_disable_timer(da9063);
	if (ret)
		dev_alert(da9063->dev, "Watchdog failed to stop (err = %d)\n",
			  ret);
	return ret;
}
static int da9063_wdt_ping(struct watchdog_device *wdd)
{
	struct da9063 *da9063 = watchdog_get_drvdata(wdd);
	int ret;
	ret = regmap_write(da9063->regmap, DA9063_REG_CONTROL_F,
			   DA9063_WATCHDOG);
	if (ret)
		dev_alert(da9063->dev, "Failed to ping the watchdog (err = %d)\n",
			  ret);
	return ret;
}
static int da9063_wdt_set_timeout(struct watchdog_device *wdd,
				  unsigned int timeout)
{
	struct da9063 *da9063 = watchdog_get_drvdata(wdd);
	int ret = 0;
	/*
	 * There are two cases when a set_timeout() will be called:
	 * 1. The watchdog is off and someone wants to set the timeout for the
	 *    further use.
	 * 2. The watchdog is already running and a new timeout value should be
	 *    set.
	 *
	 * The watchdog can't store a timeout value not equal zero without
	 * enabling the watchdog, so the timeout must be buffered by the driver.
	 */
	if (watchdog_active(wdd))
		ret = da9063_wdt_update_timeout(da9063, timeout);
	if (ret)
		dev_err(da9063->dev, "Failed to set watchdog timeout (err = %d)\n",
			ret);
	else
		wdd->timeout = wdt_timeout[da9063_wdt_timeout_to_sel(timeout)];
	return ret;
}
static int da9063_wdt_restart(struct watchdog_device *wdd, unsigned long action,
			      void *data)
{
	struct da9063 *da9063 = watchdog_get_drvdata(wdd);
	int ret;
	ret = regmap_write(da9063->regmap, DA9063_REG_CONTROL_F,
			   DA9063_SHUTDOWN);
	if (ret)
		dev_alert(da9063->dev, "Failed to shutdown (err = %d)\n",
			  ret);
	return ret;
}
static const struct watchdog_info da9063_watchdog_info = {
	.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
	.identity = "DA9063 Watchdog",
};
static const struct watchdog_ops da9063_watchdog_ops = {
	.owner = THIS_MODULE,
	.start = da9063_wdt_start,
	.stop = da9063_wdt_stop,
	.ping = da9063_wdt_ping,
	.set_timeout = da9063_wdt_set_timeout,
	.restart = da9063_wdt_restart,
};
static int da9063_wdt_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct da9063 *da9063;
	struct watchdog_device *wdd;
	unsigned int timeout;
	if (!dev->parent)
		return -EINVAL;
	da9063 = dev_get_drvdata(dev->parent);
	if (!da9063)
		return -EINVAL;
	wdd = devm_kzalloc(dev, sizeof(*wdd), GFP_KERNEL);
	if (!wdd)
		return -ENOMEM;
	wdd->info = &da9063_watchdog_info;
	wdd->ops = &da9063_watchdog_ops;
	wdd->min_timeout = DA9063_WDT_MIN_TIMEOUT;
	wdd->max_timeout = DA9063_WDT_MAX_TIMEOUT;
	wdd->min_hw_heartbeat_ms = DA9063_RESET_PROTECTION_MS;
	wdd->parent = dev;
	wdd->status = WATCHDOG_NOWAYOUT_INIT_STATUS;
	watchdog_set_restart_priority(wdd, 128);
	watchdog_set_drvdata(wdd, da9063);
	wdd->timeout = DA9063_WDG_TIMEOUT;
	/* Use pre-configured timeout if watchdog is already running. */
	timeout = da9063_wdt_read_timeout(da9063);
	if (timeout)
		wdd->timeout = timeout;
	/* Set timeout, maybe override it with DT value, scale it */
	watchdog_init_timeout(wdd, 0, dev);
	da9063_wdt_set_timeout(wdd, wdd->timeout);
	/* Update timeout if the watchdog is already running. */
	if (timeout) {
		da9063_wdt_update_timeout(da9063, wdd->timeout);
		set_bit(WDOG_HW_RUNNING, &wdd->status);
	}
	return devm_watchdog_register_device(dev, wdd);
}
static struct platform_driver da9063_wdt_driver = {
	.probe = da9063_wdt_probe,
	.driver = {
		.name = DA9063_DRVNAME_WATCHDOG,
	},
};
module_platform_driver(da9063_wdt_driver);
MODULE_AUTHOR("Mariusz Wojtasik <mariusz.wojtasik@diasemi.com>");
MODULE_DESCRIPTION("Watchdog driver for Dialog DA9063");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:" DA9063_DRVNAME_WATCHDOG);