[linux-2.6-block.git] / drivers / watchdog / da9062_wdt.c

// SPDX-License-Identifier: GPL-2.0+
/*
 * Watchdog device driver for DA9062 and DA9061 PMICs
 * Copyright (C) 2015  Dialog Semiconductor Ltd.
 *
 */

#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;
};

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)
{
	return regmap_update_bits(wdt->hw->regmap, DA9062AA_CONTROL_F,
				  DA9062AA_WATCHDOG_MASK,
				  DA9062AA_WATCHDOG_MASK);
}

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;

	regmap_update_bits(chip->regmap,
				  DA9062AA_CONTROL_D,
				  DA9062AA_TWDSCALE_MASK,
				  DA9062_TWDSCALE_DISABLE);

	usleep_range(150, 300);

	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 int da9062_wdt_restart(struct watchdog_device *wdd, unsigned long action,
			      void *data)
{
	struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd);
	int ret;

	ret = regmap_write(wdt->hw->regmap,
			   DA9062AA_CONTROL_F,
			   DA9062AA_SHUTDOWN_MASK);
	if (ret)
		dev_alert(wdt->hw->dev, "Failed to shutdown (err = %d)\n",
			  ret);

	/* wait for reset to assert... */
	mdelay(500);

	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,
	.restart = da9062_wdt_restart,
};

static const struct of_device_id da9062_compatible_id_table[] = {
	{ .compatible = "dlg,da9062-watchdog", },
	{ },
};

MODULE_DEVICE_TABLE(of, da9062_compatible_id_table);

static int da9062_wdt_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	int ret;
	struct da9062 *chip;
	struct da9062_watchdog *wdt;

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

	wdt = devm_kzalloc(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.min_hw_heartbeat_ms = DA9062_RESET_PROTECTION_MS;
	wdt->wdtdev.timeout = DA9062_WDG_DEFAULT_TIMEOUT;
	wdt->wdtdev.status = WATCHDOG_NOWAYOUT_INIT_STATUS;
	wdt->wdtdev.parent = dev;

	watchdog_set_restart_priority(&wdt->wdtdev, 128);

	watchdog_set_drvdata(&wdt->wdtdev, wdt);

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

	return da9062_wdt_ping(&wdt->wdtdev);
}

static struct platform_driver da9062_wdt_driver = {
	.probe = da9062_wdt_probe,
	.driver = {
		.name = "da9062-watchdog",
		.of_match_table = da9062_compatible_id_table,
	},
};
module_platform_driver(da9062_wdt_driver);

MODULE_AUTHOR("S Twiss <stwiss.opensource@diasemi.com>");
MODULE_DESCRIPTION("WDT device driver for Dialog DA9062 and DA9061");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:da9062-watchdog");
Commit	Line	Data
2e62c498	1	// SPDX-License-Identifier: GPL-2.0+
7a7cb009	2	/*
72106c18	3	* Watchdog device driver for DA9062 and DA9061 PMICs
7a7cb009 T	4	* Copyright (C) 2015 Dialog Semiconductor Ltd.
7a7cb009 T	5	*
7a7cb009 T	6	*/
	7
	8	#include <linux/kernel.h>
	9	#include <linux/module.h>
	10	#include <linux/watchdog.h>
	11	#include <linux/platform_device.h>
	12	#include <linux/uaccess.h>
	13	#include <linux/slab.h>
	14	#include <linux/delay.h>
	15	#include <linux/jiffies.h>
	16	#include <linux/mfd/da9062/registers.h>
	17	#include <linux/mfd/da9062/core.h>
	18	#include <linux/regmap.h>
	19	#include <linux/of.h>
	20
	21	static const unsigned int wdt_timeout[] = { 0, 2, 4, 8, 16, 32, 65, 131 };
	22	#define DA9062_TWDSCALE_DISABLE 0
	23	#define DA9062_TWDSCALE_MIN 1
	24	#define DA9062_TWDSCALE_MAX (ARRAY_SIZE(wdt_timeout) - 1)
	25	#define DA9062_WDT_MIN_TIMEOUT wdt_timeout[DA9062_TWDSCALE_MIN]
	26	#define DA9062_WDT_MAX_TIMEOUT wdt_timeout[DA9062_TWDSCALE_MAX]
	27	#define DA9062_WDG_DEFAULT_TIMEOUT wdt_timeout[DA9062_TWDSCALE_MAX-1]
	28	#define DA9062_RESET_PROTECTION_MS 300
	29
	30	struct da9062_watchdog {
	31	struct da9062 *hw;
	32	struct watchdog_device wdtdev;
7a7cb009 T	33	};
7a7cb009 T	34
7a7cb009 T	35	static unsigned int da9062_wdt_timeout_to_sel(unsigned int secs)
	36	{
	37	unsigned int i;
	38
	39	for (i = DA9062_TWDSCALE_MIN; i <= DA9062_TWDSCALE_MAX; i++) {
	40	if (wdt_timeout[i] >= secs)
	41	return i;
	42	}
	43
	44	return DA9062_TWDSCALE_MAX;
	45	}
	46
	47	static int da9062_reset_watchdog_timer(struct da9062_watchdog *wdt)
	48	{
6e8a7c75 GR	49	return regmap_update_bits(wdt->hw->regmap, DA9062AA_CONTROL_F,
	50	DA9062AA_WATCHDOG_MASK,
	51	DA9062AA_WATCHDOG_MASK);
7a7cb009 T	52	}
	53
	54	static int da9062_wdt_update_timeout_register(struct da9062_watchdog *wdt,
	55	unsigned int regval)
	56	{
	57	struct da9062 *chip = wdt->hw;
	58	int ret;
	59
	60	ret = da9062_reset_watchdog_timer(wdt);
	61	if (ret)
	62	return ret;
	63
f31b2a9b MG	64	regmap_update_bits(chip->regmap,
	65	DA9062AA_CONTROL_D,
	66	DA9062AA_TWDSCALE_MASK,
	67	DA9062_TWDSCALE_DISABLE);
	68
	69	usleep_range(150, 300);
	70
7a7cb009 T	71	return regmap_update_bits(chip->regmap,
	72	DA9062AA_CONTROL_D,
	73	DA9062AA_TWDSCALE_MASK,
	74	regval);
	75	}
	76
	77	static int da9062_wdt_start(struct watchdog_device *wdd)
	78	{
	79	struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd);
	80	unsigned int selector;
	81	int ret;
	82
	83	selector = da9062_wdt_timeout_to_sel(wdt->wdtdev.timeout);
	84	ret = da9062_wdt_update_timeout_register(wdt, selector);
	85	if (ret)
	86	dev_err(wdt->hw->dev, "Watchdog failed to start (err = %d)\n",
	87	ret);
	88
	89	return ret;
	90	}
	91
	92	static int da9062_wdt_stop(struct watchdog_device *wdd)
	93	{
	94	struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd);
	95	int ret;
	96
	97	ret = da9062_reset_watchdog_timer(wdt);
	98	if (ret) {
	99	dev_err(wdt->hw->dev, "Failed to ping the watchdog (err = %d)\n",
	100	ret);
	101	return ret;
	102	}
	103
	104	ret = regmap_update_bits(wdt->hw->regmap,
	105	DA9062AA_CONTROL_D,
	106	DA9062AA_TWDSCALE_MASK,
	107	DA9062_TWDSCALE_DISABLE);
	108	if (ret)
	109	dev_err(wdt->hw->dev, "Watchdog failed to stop (err = %d)\n",
	110	ret);
	111
	112	return ret;
	113	}
	114
	115	static int da9062_wdt_ping(struct watchdog_device *wdd)
	116	{
	117	struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd);
	118	int ret;
	119
	120	ret = da9062_reset_watchdog_timer(wdt);
	121	if (ret)
	122	dev_err(wdt->hw->dev, "Failed to ping the watchdog (err = %d)\n",
	123	ret);
	124
	125	return ret;
	126	}
	127
	128	static int da9062_wdt_set_timeout(struct watchdog_device *wdd,
	129	unsigned int timeout)
	130	{
	131	struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd);
	132	unsigned int selector;
	133	int ret;
	134
135	selector = da9062_wdt_timeout_to_sel(timeout);
136	ret = da9062_wdt_update_timeout_register(wdt, selector);
137	if (ret)
138	dev_err(wdt->hw->dev, "Failed to set watchdog timeout (err = %d)\n",
139	ret);
140	else
141	wdd->timeout = wdt_timeout[selector];
142
143	return ret;
144	}
145
540f6351 MG	146	static int da9062_wdt_restart(struct watchdog_device *wdd, unsigned long action,
	147	void *data)
	148	{
	149	struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd);
	150	int ret;
	151
	152	ret = regmap_write(wdt->hw->regmap,
	153	DA9062AA_CONTROL_F,
	154	DA9062AA_SHUTDOWN_MASK);
	155	if (ret)
	156	dev_alert(wdt->hw->dev, "Failed to shutdown (err = %d)\n",
	157	ret);
	158
	159	/* wait for reset to assert... */
	160	mdelay(500);
	161
	162	return ret;
	163	}
	164
7a7cb009 T	165	static const struct watchdog_info da9062_watchdog_info = {
	166	.options = WDIOF_SETTIMEOUT \| WDIOF_KEEPALIVEPING,
	167	.identity = "DA9062 WDT",
	168	};
	169
	170	static const struct watchdog_ops da9062_watchdog_ops = {
	171	.owner = THIS_MODULE,
	172	.start = da9062_wdt_start,
	173	.stop = da9062_wdt_stop,
	174	.ping = da9062_wdt_ping,
	175	.set_timeout = da9062_wdt_set_timeout,
540f6351	176	.restart = da9062_wdt_restart,
7a7cb009 T	177	};
7a7cb009 T	178
72106c18 ST	179	static const struct of_device_id da9062_compatible_id_table[] = {
	180	{ .compatible = "dlg,da9062-watchdog", },
	181	{ },
	182	};
	183
	184	MODULE_DEVICE_TABLE(of, da9062_compatible_id_table);
	185
7a7cb009 T	186	static int da9062_wdt_probe(struct platform_device *pdev)
7a7cb009 T	187	{
6e8a7c75	188	struct device *dev = &pdev->dev;
7a7cb009 T	189	int ret;
	190	struct da9062 *chip;
	191	struct da9062_watchdog *wdt;
	192
6e8a7c75	193	chip = dev_get_drvdata(dev->parent);
7a7cb009 T	194	if (!chip)
	195	return -EINVAL;
	196
6e8a7c75	197	wdt = devm_kzalloc(dev, sizeof(*wdt), GFP_KERNEL);
7a7cb009 T	198	if (!wdt)
	199	return -ENOMEM;
	200
	201	wdt->hw = chip;
	202
	203	wdt->wdtdev.info = &da9062_watchdog_info;
	204	wdt->wdtdev.ops = &da9062_watchdog_ops;
	205	wdt->wdtdev.min_timeout = DA9062_WDT_MIN_TIMEOUT;
	206	wdt->wdtdev.max_timeout = DA9062_WDT_MAX_TIMEOUT;
fb484262	207	wdt->wdtdev.min_hw_heartbeat_ms = DA9062_RESET_PROTECTION_MS;
7a7cb009 T	208	wdt->wdtdev.timeout = DA9062_WDG_DEFAULT_TIMEOUT;
7a7cb009 T	209	wdt->wdtdev.status = WATCHDOG_NOWAYOUT_INIT_STATUS;
6e8a7c75	210	wdt->wdtdev.parent = dev;
7a7cb009	211
540f6351 MG	212	watchdog_set_restart_priority(&wdt->wdtdev, 128);
540f6351 MG	213
7a7cb009	214	watchdog_set_drvdata(&wdt->wdtdev, wdt);
7a7cb009	215
6e8a7c75	216	ret = devm_watchdog_register_device(dev, &wdt->wdtdev);
7a7cb009 T	217	if (ret < 0) {
	218	dev_err(wdt->hw->dev,
	219	"watchdog registration failed (%d)\n", ret);
	220	return ret;
	221	}
	222
528eff34	223	return da9062_wdt_ping(&wdt->wdtdev);
7a7cb009 T	224	}
	225
	226	static struct platform_driver da9062_wdt_driver = {
	227	.probe = da9062_wdt_probe,
7a7cb009 T	228	.driver = {
7a7cb009 T	229	.name = "da9062-watchdog",
72106c18	230	.of_match_table = da9062_compatible_id_table,
7a7cb009 T	231	},
	232	};
	233	module_platform_driver(da9062_wdt_driver);
	234
	235	MODULE_AUTHOR("S Twiss <stwiss.opensource@diasemi.com>");
72106c18	236	MODULE_DESCRIPTION("WDT device driver for Dialog DA9062 and DA9061");
7a7cb009 T	237	MODULE_LICENSE("GPL");
7a7cb009 T	238	MODULE_ALIAS("platform:da9062-watchdog");