[mirror_ubuntu-hirsute-kernel.git] / drivers / watchdog / da9063_wdt.c

// 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;
}

static int _da9063_wdt_set_timeout(struct da9063 *da9063, unsigned int regval)
{
	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);
	unsigned int selector;
	int ret;

	selector = da9063_wdt_timeout_to_sel(wdd->timeout);
	ret = _da9063_wdt_set_timeout(da9063, selector);
	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 = regmap_update_bits(da9063->regmap, DA9063_REG_CONTROL_D,
				 DA9063_TWDSCALE_MASK, DA9063_TWDSCALE_DISABLE);
	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);
	unsigned int selector;
	int ret;

	selector = da9063_wdt_timeout_to_sel(timeout);
	ret = _da9063_wdt_set_timeout(da9063, selector);
	if (ret)
		dev_err(da9063->dev, "Failed to set watchdog timeout (err = %d)\n",
			ret);
	else
		wdd->timeout = wdt_timeout[selector];

	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 da9063 *da9063;
	struct watchdog_device *wdd;

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

	da9063 = dev_get_drvdata(pdev->dev.parent);
	if (!da9063)
		return -EINVAL;

	wdd = devm_kzalloc(&pdev->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->timeout = DA9063_WDG_TIMEOUT;
	wdd->parent = &pdev->dev;

	wdd->status = WATCHDOG_NOWAYOUT_INIT_STATUS;

	watchdog_set_restart_priority(wdd, 128);

	watchdog_set_drvdata(wdd, da9063);

	return devm_watchdog_register_device(&pdev->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);
Commit	Line	Data
2e62c498	1	// SPDX-License-Identifier: GPL-2.0+
5e9c16e3 KG	2	/*
	3	* Watchdog driver for DA9063 PMICs.
	4	*
	5	* Copyright(c) 2012 Dialog Semiconductor Ltd.
	6	*
	7	* Author: Mariusz Wojtasik <mariusz.wojtasik@diasemi.com>
	8	*
5e9c16e3 KG	9	*/
	10
	11	#include <linux/kernel.h>
	12	#include <linux/module.h>
	13	#include <linux/watchdog.h>
	14	#include <linux/platform_device.h>
	15	#include <linux/uaccess.h>
	16	#include <linux/slab.h>
	17	#include <linux/delay.h>
	18	#include <linux/mfd/da9063/registers.h>
	19	#include <linux/mfd/da9063/core.h>
	20	#include <linux/regmap.h>
	21
	22	/*
	23	* Watchdog selector to timeout in seconds.
	24	* 0: WDT disabled;
	25	* others: timeout = 2048 ms * 2^(TWDSCALE-1).
	26	*/
	27	static const unsigned int wdt_timeout[] = { 0, 2, 4, 8, 16, 32, 65, 131 };
	28	#define DA9063_TWDSCALE_DISABLE 0
	29	#define DA9063_TWDSCALE_MIN 1
	30	#define DA9063_TWDSCALE_MAX (ARRAY_SIZE(wdt_timeout) - 1)
	31	#define DA9063_WDT_MIN_TIMEOUT wdt_timeout[DA9063_TWDSCALE_MIN]
	32	#define DA9063_WDT_MAX_TIMEOUT wdt_timeout[DA9063_TWDSCALE_MAX]
	33	#define DA9063_WDG_TIMEOUT wdt_timeout[3]
a74cab40	34	#define DA9063_RESET_PROTECTION_MS 256
5e9c16e3	35
5e9c16e3 KG	36	static unsigned int da9063_wdt_timeout_to_sel(unsigned int secs)
	37	{
	38	unsigned int i;
	39
	40	for (i = DA9063_TWDSCALE_MIN; i <= DA9063_TWDSCALE_MAX; i++) {
	41	if (wdt_timeout[i] >= secs)
	42	return i;
	43	}
	44
	45	return DA9063_TWDSCALE_MAX;
	46	}
	47
	48	static int _da9063_wdt_set_timeout(struct da9063 *da9063, unsigned int regval)
	49	{
	50	return regmap_update_bits(da9063->regmap, DA9063_REG_CONTROL_D,
	51	DA9063_TWDSCALE_MASK, regval);
	52	}
	53
	54	static int da9063_wdt_start(struct watchdog_device *wdd)
	55	{
a1f2a820	56	struct da9063 *da9063 = watchdog_get_drvdata(wdd);
5e9c16e3 KG	57	unsigned int selector;
	58	int ret;
	59
a1f2a820	60	selector = da9063_wdt_timeout_to_sel(wdd->timeout);
a1f2a820	61	ret = _da9063_wdt_set_timeout(da9063, selector);
5e9c16e3	62	if (ret)
a1f2a820	63	dev_err(da9063->dev, "Watchdog failed to start (err = %d)\n",
5e9c16e3 KG	64	ret);
	65
	66	return ret;
	67	}
	68
	69	static int da9063_wdt_stop(struct watchdog_device *wdd)
	70	{
a1f2a820	71	struct da9063 *da9063 = watchdog_get_drvdata(wdd);
5e9c16e3 KG	72	int ret;
5e9c16e3 KG	73
a1f2a820	74	ret = regmap_update_bits(da9063->regmap, DA9063_REG_CONTROL_D,
5e9c16e3 KG	75	DA9063_TWDSCALE_MASK, DA9063_TWDSCALE_DISABLE);
5e9c16e3 KG	76	if (ret)
a1f2a820	77	dev_alert(da9063->dev, "Watchdog failed to stop (err = %d)\n",
5e9c16e3 KG	78	ret);
	79
	80	return ret;
	81	}
	82
	83	static int da9063_wdt_ping(struct watchdog_device *wdd)
	84	{
a1f2a820	85	struct da9063 *da9063 = watchdog_get_drvdata(wdd);
5e9c16e3 KG	86	int ret;
5e9c16e3 KG	87
a1f2a820	88	ret = regmap_write(da9063->regmap, DA9063_REG_CONTROL_F,
5e9c16e3 KG	89	DA9063_WATCHDOG);
5e9c16e3 KG	90	if (ret)
a1f2a820	91	dev_alert(da9063->dev, "Failed to ping the watchdog (err = %d)\n",
5e9c16e3 KG	92	ret);
	93
	94	return ret;
	95	}
	96
	97	static int da9063_wdt_set_timeout(struct watchdog_device *wdd,
	98	unsigned int timeout)
	99	{
a1f2a820	100	struct da9063 *da9063 = watchdog_get_drvdata(wdd);
5e9c16e3 KG	101	unsigned int selector;
	102	int ret;
	103
	104	selector = da9063_wdt_timeout_to_sel(timeout);
a1f2a820	105	ret = _da9063_wdt_set_timeout(da9063, selector);
5e9c16e3	106	if (ret)
a1f2a820	107	dev_err(da9063->dev, "Failed to set watchdog timeout (err = %d)\n",
5e9c16e3 KG	108	ret);
	109	else
	110	wdd->timeout = wdt_timeout[selector];
	111
	112	return ret;
	113	}
	114
4d8b229d GR	115	static int da9063_wdt_restart(struct watchdog_device *wdd, unsigned long action,
4d8b229d GR	116	void *data)
396f163c	117	{
a1f2a820	118	struct da9063 *da9063 = watchdog_get_drvdata(wdd);
396f163c GU	119	int ret;
396f163c GU	120
a1f2a820	121	ret = regmap_write(da9063->regmap, DA9063_REG_CONTROL_F,
396f163c GU	122	DA9063_SHUTDOWN);
396f163c GU	123	if (ret)
a1f2a820	124	dev_alert(da9063->dev, "Failed to shutdown (err = %d)\n",
396f163c GU	125	ret);
396f163c GU	126
f79781ce	127	return ret;
396f163c GU	128	}
396f163c GU	129
5e9c16e3 KG	130	static const struct watchdog_info da9063_watchdog_info = {
	131	.options = WDIOF_SETTIMEOUT \| WDIOF_KEEPALIVEPING,
	132	.identity = "DA9063 Watchdog",
	133	};
	134
	135	static const struct watchdog_ops da9063_watchdog_ops = {
	136	.owner = THIS_MODULE,
	137	.start = da9063_wdt_start,
	138	.stop = da9063_wdt_stop,
	139	.ping = da9063_wdt_ping,
	140	.set_timeout = da9063_wdt_set_timeout,
f79781ce	141	.restart = da9063_wdt_restart,
5e9c16e3 KG	142	};
	143
	144	static int da9063_wdt_probe(struct platform_device *pdev)
	145	{
5e9c16e3	146	struct da9063 *da9063;
a1f2a820	147	struct watchdog_device *wdd;
5e9c16e3 KG	148
	149	if (!pdev->dev.parent)
	150	return -EINVAL;
	151
	152	da9063 = dev_get_drvdata(pdev->dev.parent);
	153	if (!da9063)
	154	return -EINVAL;
	155
a1f2a820	156	wdd = devm_kzalloc(&pdev->dev, sizeof(*wdd), GFP_KERNEL);
a1f2a820	157	if (!wdd)
5e9c16e3 KG	158	return -ENOMEM;
5e9c16e3 KG	159
a1f2a820	160	wdd->info = &da9063_watchdog_info;
	161	wdd->ops = &da9063_watchdog_ops;
	162	wdd->min_timeout = DA9063_WDT_MIN_TIMEOUT;
	163	wdd->max_timeout = DA9063_WDT_MAX_TIMEOUT;
	164	wdd->min_hw_heartbeat_ms = DA9063_RESET_PROTECTION_MS;
	165	wdd->timeout = DA9063_WDG_TIMEOUT;
	166	wdd->parent = &pdev->dev;
5e9c16e3	167
a1f2a820	168	wdd->status = WATCHDOG_NOWAYOUT_INIT_STATUS;
5e9c16e3	169
a1f2a820	170	watchdog_set_restart_priority(wdd, 128);
f79781ce	171
a1f2a820	172	watchdog_set_drvdata(wdd, da9063);
5e9c16e3	173
a1f2a820	174	return devm_watchdog_register_device(&pdev->dev, wdd);
5e9c16e3 KG	175	}
	176
	177	static struct platform_driver da9063_wdt_driver = {
	178	.probe = da9063_wdt_probe,
5e9c16e3 KG	179	.driver = {
	180	.name = DA9063_DRVNAME_WATCHDOG,
	181	},
	182	};
	183	module_platform_driver(da9063_wdt_driver);
	184
	185	MODULE_AUTHOR("Mariusz Wojtasik <mariusz.wojtasik@diasemi.com>");
	186	MODULE_DESCRIPTION("Watchdog driver for Dialog DA9063");
	187	MODULE_LICENSE("GPL");
	188	MODULE_ALIAS("platform:" DA9063_DRVNAME_WATCHDOG);