[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)
{
	int ret;

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

	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;

	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)
{
	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.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 = &pdev->dev;

	watchdog_set_restart_priority(&wdt->wdtdev, 128);

	watchdog_set_drvdata(&wdt->wdtdev, wdt);

	ret = devm_watchdog_register_device(&pdev->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	{
	49	int ret;
	50
7a7cb009 T	51	ret = regmap_update_bits(wdt->hw->regmap,
	52	DA9062AA_CONTROL_F,
	53	DA9062AA_WATCHDOG_MASK,
	54	DA9062AA_WATCHDOG_MASK);
	55
7a7cb009 T	56	return ret;
	57	}
	58
	59	static int da9062_wdt_update_timeout_register(struct da9062_watchdog *wdt,
	60	unsigned int regval)
	61	{
	62	struct da9062 *chip = wdt->hw;
	63	int ret;
	64
	65	ret = da9062_reset_watchdog_timer(wdt);
	66	if (ret)
	67	return ret;
	68
f31b2a9b MG	69	regmap_update_bits(chip->regmap,
	70	DA9062AA_CONTROL_D,
	71	DA9062AA_TWDSCALE_MASK,
	72	DA9062_TWDSCALE_DISABLE);
	73
	74	usleep_range(150, 300);
	75
7a7cb009 T	76	return regmap_update_bits(chip->regmap,
	77	DA9062AA_CONTROL_D,
	78	DA9062AA_TWDSCALE_MASK,
	79	regval);
	80	}
	81
	82	static int da9062_wdt_start(struct watchdog_device *wdd)
	83	{
	84	struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd);
	85	unsigned int selector;
	86	int ret;
	87
	88	selector = da9062_wdt_timeout_to_sel(wdt->wdtdev.timeout);
	89	ret = da9062_wdt_update_timeout_register(wdt, selector);
	90	if (ret)
	91	dev_err(wdt->hw->dev, "Watchdog failed to start (err = %d)\n",
	92	ret);
	93
	94	return ret;
	95	}
	96
	97	static int da9062_wdt_stop(struct watchdog_device *wdd)
	98	{
	99	struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd);
	100	int ret;
	101
	102	ret = da9062_reset_watchdog_timer(wdt);
	103	if (ret) {
	104	dev_err(wdt->hw->dev, "Failed to ping the watchdog (err = %d)\n",
	105	ret);
	106	return ret;
	107	}
	108
	109	ret = regmap_update_bits(wdt->hw->regmap,
	110	DA9062AA_CONTROL_D,
	111	DA9062AA_TWDSCALE_MASK,
	112	DA9062_TWDSCALE_DISABLE);
	113	if (ret)
	114	dev_err(wdt->hw->dev, "Watchdog failed to stop (err = %d)\n",
	115	ret);
	116
	117	return ret;
	118	}
	119
	120	static int da9062_wdt_ping(struct watchdog_device *wdd)
	121	{
	122	struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd);
	123	int ret;
	124
	125	ret = da9062_reset_watchdog_timer(wdt);
	126	if (ret)
	127	dev_err(wdt->hw->dev, "Failed to ping the watchdog (err = %d)\n",
	128	ret);
	129
	130	return ret;
	131	}
	132
	133	static int da9062_wdt_set_timeout(struct watchdog_device *wdd,
	134	unsigned int timeout)
	135	{
	136	struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd);
	137	unsigned int selector;
	138	int ret;
	139
140	selector = da9062_wdt_timeout_to_sel(timeout);
141	ret = da9062_wdt_update_timeout_register(wdt, selector);
142	if (ret)
143	dev_err(wdt->hw->dev, "Failed to set watchdog timeout (err = %d)\n",
144	ret);
145	else
146	wdd->timeout = wdt_timeout[selector];
147
148	return ret;
149	}
150
540f6351 MG	151	static int da9062_wdt_restart(struct watchdog_device *wdd, unsigned long action,
	152	void *data)
	153	{
	154	struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd);
	155	int ret;
	156
	157	ret = regmap_write(wdt->hw->regmap,
	158	DA9062AA_CONTROL_F,
	159	DA9062AA_SHUTDOWN_MASK);
	160	if (ret)
	161	dev_alert(wdt->hw->dev, "Failed to shutdown (err = %d)\n",
	162	ret);
	163
	164	/* wait for reset to assert... */
	165	mdelay(500);
	166
	167	return ret;
	168	}
	169
7a7cb009 T	170	static const struct watchdog_info da9062_watchdog_info = {
	171	.options = WDIOF_SETTIMEOUT \| WDIOF_KEEPALIVEPING,
	172	.identity = "DA9062 WDT",
	173	};
	174
	175	static const struct watchdog_ops da9062_watchdog_ops = {
	176	.owner = THIS_MODULE,
	177	.start = da9062_wdt_start,
	178	.stop = da9062_wdt_stop,
	179	.ping = da9062_wdt_ping,
	180	.set_timeout = da9062_wdt_set_timeout,
540f6351	181	.restart = da9062_wdt_restart,
7a7cb009 T	182	};
7a7cb009 T	183
72106c18 ST	184	static const struct of_device_id da9062_compatible_id_table[] = {
	185	{ .compatible = "dlg,da9062-watchdog", },
	186	{ },
	187	};
	188
	189	MODULE_DEVICE_TABLE(of, da9062_compatible_id_table);
	190
7a7cb009 T	191	static int da9062_wdt_probe(struct platform_device *pdev)
	192	{
	193	int ret;
	194	struct da9062 *chip;
	195	struct da9062_watchdog *wdt;
	196
	197	chip = dev_get_drvdata(pdev->dev.parent);
	198	if (!chip)
	199	return -EINVAL;
	200
	201	wdt = devm_kzalloc(&pdev->dev, sizeof(*wdt), GFP_KERNEL);
	202	if (!wdt)
	203	return -ENOMEM;
	204
	205	wdt->hw = chip;
	206
	207	wdt->wdtdev.info = &da9062_watchdog_info;
	208	wdt->wdtdev.ops = &da9062_watchdog_ops;
	209	wdt->wdtdev.min_timeout = DA9062_WDT_MIN_TIMEOUT;
	210	wdt->wdtdev.max_timeout = DA9062_WDT_MAX_TIMEOUT;
fb484262	211	wdt->wdtdev.min_hw_heartbeat_ms = DA9062_RESET_PROTECTION_MS;
7a7cb009 T	212	wdt->wdtdev.timeout = DA9062_WDG_DEFAULT_TIMEOUT;
7a7cb009 T	213	wdt->wdtdev.status = WATCHDOG_NOWAYOUT_INIT_STATUS;
6551881c	214	wdt->wdtdev.parent = &pdev->dev;
7a7cb009	215
540f6351 MG	216	watchdog_set_restart_priority(&wdt->wdtdev, 128);
540f6351 MG	217
7a7cb009	218	watchdog_set_drvdata(&wdt->wdtdev, wdt);
7a7cb009	219
528eff34	220	ret = devm_watchdog_register_device(&pdev->dev, &wdt->wdtdev);
7a7cb009 T	221	if (ret < 0) {
	222	dev_err(wdt->hw->dev,
	223	"watchdog registration failed (%d)\n", ret);
	224	return ret;
	225	}
	226
528eff34	227	return da9062_wdt_ping(&wdt->wdtdev);
7a7cb009 T	228	}
	229
	230	static struct platform_driver da9062_wdt_driver = {
	231	.probe = da9062_wdt_probe,
7a7cb009 T	232	.driver = {
7a7cb009 T	233	.name = "da9062-watchdog",
72106c18	234	.of_match_table = da9062_compatible_id_table,
7a7cb009 T	235	},
	236	};
	237	module_platform_driver(da9062_wdt_driver);
	238
	239	MODULE_AUTHOR("S Twiss <stwiss.opensource@diasemi.com>");
72106c18	240	MODULE_DESCRIPTION("WDT device driver for Dialog DA9062 and DA9061");
7a7cb009 T	241	MODULE_LICENSE("GPL");
7a7cb009 T	242	MODULE_ALIAS("platform:da9062-watchdog");