[deliverable/linux.git] / drivers / watchdog / dw_wdt.c

/*
 * Copyright 2010-2011 Picochip Ltd., Jamie Iles
 * http://www.picochip.com
 *
 * 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 file implements a driver for the Synopsys DesignWare watchdog device
 * in the many subsystems. The watchdog has 16 different timeout periods
 * and these are a function of the input clock frequency.
 *
 * The DesignWare watchdog cannot be stopped once it has been started so we
 * use a software timer to implement a ping that will keep the watchdog alive.
 * If we receive an expected close for the watchdog then we keep the timer
 * running, otherwise the timer is stopped and the watchdog will expire.
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/bitops.h>
#include <linux/clk.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/fs.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/miscdevice.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/of.h>
#include <linux/pm.h>
#include <linux/platform_device.h>
#include <linux/spinlock.h>
#include <linux/timer.h>
#include <linux/uaccess.h>
#include <linux/watchdog.h>

#define WDOG_CONTROL_REG_OFFSET		    0x00
#define WDOG_CONTROL_REG_WDT_EN_MASK	    0x01
#define WDOG_TIMEOUT_RANGE_REG_OFFSET	    0x04
#define WDOG_TIMEOUT_RANGE_TOPINIT_SHIFT    4
#define WDOG_CURRENT_COUNT_REG_OFFSET	    0x08
#define WDOG_COUNTER_RESTART_REG_OFFSET     0x0c
#define WDOG_COUNTER_RESTART_KICK_VALUE	    0x76

/* The maximum TOP (timeout period) value that can be set in the watchdog. */
#define DW_WDT_MAX_TOP		15

static bool nowayout = WATCHDOG_NOWAYOUT;
module_param(nowayout, bool, 0);
MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started "
		 "(default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");

#define WDT_TIMEOUT		(HZ / 2)

static struct {
	spinlock_t		lock;
	void __iomem		*regs;
	struct clk		*clk;
	unsigned long		in_use;
	unsigned long		next_heartbeat;
	struct timer_list	timer;
	int			expect_close;
} dw_wdt;

static inline int dw_wdt_is_enabled(void)
{
	return readl(dw_wdt.regs + WDOG_CONTROL_REG_OFFSET) &
		WDOG_CONTROL_REG_WDT_EN_MASK;
}

static inline int dw_wdt_top_in_seconds(unsigned top)
{
	/*
	 * There are 16 possible timeout values in 0..15 where the number of
	 * cycles is 2 ^ (16 + i) and the watchdog counts down.
	 */
	return (1 << (16 + top)) / clk_get_rate(dw_wdt.clk);
}

static int dw_wdt_get_top(void)
{
	int top = readl(dw_wdt.regs + WDOG_TIMEOUT_RANGE_REG_OFFSET) & 0xF;

	return dw_wdt_top_in_seconds(top);
}

static inline void dw_wdt_set_next_heartbeat(void)
{
	dw_wdt.next_heartbeat = jiffies + dw_wdt_get_top() * HZ;
}

static int dw_wdt_set_top(unsigned top_s)
{
	int i, top_val = DW_WDT_MAX_TOP;

	/*
	 * Iterate over the timeout values until we find the closest match. We
	 * always look for >=.
	 */
	for (i = 0; i <= DW_WDT_MAX_TOP; ++i)
		if (dw_wdt_top_in_seconds(i) >= top_s) {
			top_val = i;
			break;
		}

	/* Set the new value in the watchdog. */
	writel(top_val | top_val << WDOG_TIMEOUT_RANGE_TOPINIT_SHIFT,
		dw_wdt.regs + WDOG_TIMEOUT_RANGE_REG_OFFSET);

	dw_wdt_set_next_heartbeat();

	return dw_wdt_top_in_seconds(top_val);
}

static void dw_wdt_keepalive(void)
{
	writel(WDOG_COUNTER_RESTART_KICK_VALUE, dw_wdt.regs +
	       WDOG_COUNTER_RESTART_REG_OFFSET);
}

static void dw_wdt_ping(unsigned long data)
{
	if (time_before(jiffies, dw_wdt.next_heartbeat) ||
	    (!nowayout && !dw_wdt.in_use)) {
		dw_wdt_keepalive();
		mod_timer(&dw_wdt.timer, jiffies + WDT_TIMEOUT);
	} else
		pr_crit("keepalive missed, machine will reset\n");
}

static int dw_wdt_open(struct inode *inode, struct file *filp)
{
	if (test_and_set_bit(0, &dw_wdt.in_use))
		return -EBUSY;

	/* Make sure we don't get unloaded. */
	__module_get(THIS_MODULE);

	spin_lock(&dw_wdt.lock);
	if (!dw_wdt_is_enabled()) {
		/*
		 * The watchdog is not currently enabled. Set the timeout to
		 * the maximum and then start it.
		 */
		dw_wdt_set_top(DW_WDT_MAX_TOP);
		writel(WDOG_CONTROL_REG_WDT_EN_MASK,
		       dw_wdt.regs + WDOG_CONTROL_REG_OFFSET);
	}

	dw_wdt_set_next_heartbeat();

	spin_unlock(&dw_wdt.lock);

	return nonseekable_open(inode, filp);
}

static ssize_t dw_wdt_write(struct file *filp, const char __user *buf,
			    size_t len, loff_t *offset)
{
	if (!len)
		return 0;

	if (!nowayout) {
		size_t i;

		dw_wdt.expect_close = 0;

		for (i = 0; i < len; ++i) {
			char c;

			if (get_user(c, buf + i))
				return -EFAULT;

			if (c == 'V') {
				dw_wdt.expect_close = 1;
				break;
			}
		}
	}

	dw_wdt_set_next_heartbeat();
	mod_timer(&dw_wdt.timer, jiffies + WDT_TIMEOUT);

	return len;
}

static u32 dw_wdt_time_left(void)
{
	return readl(dw_wdt.regs + WDOG_CURRENT_COUNT_REG_OFFSET) /
		clk_get_rate(dw_wdt.clk);
}

static const struct watchdog_info dw_wdt_ident = {
	.options	= WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT |
			  WDIOF_MAGICCLOSE,
	.identity	= "Synopsys DesignWare Watchdog",
};

static long dw_wdt_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
	unsigned long val;
	int timeout;

	switch (cmd) {
	case WDIOC_GETSUPPORT:
		return copy_to_user((void __user *)arg, &dw_wdt_ident,
				    sizeof(dw_wdt_ident)) ? -EFAULT : 0;

	case WDIOC_GETSTATUS:
	case WDIOC_GETBOOTSTATUS:
		return put_user(0, (int __user *)arg);

	case WDIOC_KEEPALIVE:
		dw_wdt_set_next_heartbeat();
		return 0;

	case WDIOC_SETTIMEOUT:
		if (get_user(val, (int __user *)arg))
			return -EFAULT;
		timeout = dw_wdt_set_top(val);
		return put_user(timeout , (int __user *)arg);

	case WDIOC_GETTIMEOUT:
		return put_user(dw_wdt_get_top(), (int __user *)arg);

	case WDIOC_GETTIMELEFT:
		/* Get the time left until expiry. */
		if (get_user(val, (int __user *)arg))
			return -EFAULT;
		return put_user(dw_wdt_time_left(), (int __user *)arg);

	default:
		return -ENOTTY;
	}
}

static int dw_wdt_release(struct inode *inode, struct file *filp)
{
	clear_bit(0, &dw_wdt.in_use);

	if (!dw_wdt.expect_close) {
		del_timer(&dw_wdt.timer);

		if (!nowayout)
			pr_crit("unexpected close, system will reboot soon\n");
		else
			pr_crit("watchdog cannot be disabled, system will reboot soon\n");
	}

	dw_wdt.expect_close = 0;

	return 0;
}

#ifdef CONFIG_PM_SLEEP
static int dw_wdt_suspend(struct device *dev)
{
	clk_disable_unprepare(dw_wdt.clk);

	return 0;
}

static int dw_wdt_resume(struct device *dev)
{
	int err = clk_prepare_enable(dw_wdt.clk);

	if (err)
		return err;

	dw_wdt_keepalive();

	return 0;
}
#endif /* CONFIG_PM_SLEEP */

static SIMPLE_DEV_PM_OPS(dw_wdt_pm_ops, dw_wdt_suspend, dw_wdt_resume);

static const struct file_operations wdt_fops = {
	.owner		= THIS_MODULE,
	.llseek		= no_llseek,
	.open		= dw_wdt_open,
	.write		= dw_wdt_write,
	.unlocked_ioctl	= dw_wdt_ioctl,
	.release	= dw_wdt_release
};

static struct miscdevice dw_wdt_miscdev = {
	.fops		= &wdt_fops,
	.name		= "watchdog",
	.minor		= WATCHDOG_MINOR,
};

static int dw_wdt_drv_probe(struct platform_device *pdev)
{
	int ret;
	struct resource *mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);

	dw_wdt.regs = devm_ioremap_resource(&pdev->dev, mem);
	if (IS_ERR(dw_wdt.regs))
		return PTR_ERR(dw_wdt.regs);

	dw_wdt.clk = devm_clk_get(&pdev->dev, NULL);
	if (IS_ERR(dw_wdt.clk))
		return PTR_ERR(dw_wdt.clk);

	ret = clk_prepare_enable(dw_wdt.clk);
	if (ret)
		return ret;

	spin_lock_init(&dw_wdt.lock);

	ret = misc_register(&dw_wdt_miscdev);
	if (ret)
		goto out_disable_clk;

	dw_wdt_set_next_heartbeat();
	setup_timer(&dw_wdt.timer, dw_wdt_ping, 0);
	mod_timer(&dw_wdt.timer, jiffies + WDT_TIMEOUT);

	return 0;

out_disable_clk:
	clk_disable_unprepare(dw_wdt.clk);

	return ret;
}

static int dw_wdt_drv_remove(struct platform_device *pdev)
{
	misc_deregister(&dw_wdt_miscdev);

	clk_disable_unprepare(dw_wdt.clk);

	return 0;
}

#ifdef CONFIG_OF
static const struct of_device_id dw_wdt_of_match[] = {
	{ .compatible = "snps,dw-wdt", },
	{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, dw_wdt_of_match);
#endif

static struct platform_driver dw_wdt_driver = {
	.probe		= dw_wdt_drv_probe,
	.remove		= dw_wdt_drv_remove,
	.driver		= {
		.name	= "dw_wdt",
		.owner	= THIS_MODULE,
		.of_match_table = of_match_ptr(dw_wdt_of_match),
		.pm	= &dw_wdt_pm_ops,
	},
};

module_platform_driver(dw_wdt_driver);

MODULE_AUTHOR("Jamie Iles");
MODULE_DESCRIPTION("Synopsys DesignWare Watchdog Driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
c9353ae1 JI	1	/*
	2	* Copyright 2010-2011 Picochip Ltd., Jamie Iles
	3	* http://www.picochip.com
	4	*
	5	* This program is free software; you can redistribute it and/or
	6	* modify it under the terms of the GNU General Public License
	7	* as published by the Free Software Foundation; either version
	8	* 2 of the License, or (at your option) any later version.
	9	*
	10	* This file implements a driver for the Synopsys DesignWare watchdog device
58a251f2	11	* in the many subsystems. The watchdog has 16 different timeout periods
c9353ae1 JI	12	* and these are a function of the input clock frequency.
	13	*
	14	* The DesignWare watchdog cannot be stopped once it has been started so we
	15	* use a software timer to implement a ping that will keep the watchdog alive.
	16	* If we receive an expected close for the watchdog then we keep the timer
	17	* running, otherwise the timer is stopped and the watchdog will expire.
	18	*/
27c766aa JP	19
27c766aa JP	20	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
c9353ae1 JI	21
	22	#include <linux/bitops.h>
	23	#include <linux/clk.h>
	24	#include <linux/device.h>
	25	#include <linux/err.h>
	26	#include <linux/fs.h>
	27	#include <linux/io.h>
	28	#include <linux/kernel.h>
	29	#include <linux/miscdevice.h>
	30	#include <linux/module.h>
	31	#include <linux/moduleparam.h>
58e56373	32	#include <linux/of.h>
c9353ae1 JI	33	#include <linux/pm.h>
	34	#include <linux/platform_device.h>
	35	#include <linux/spinlock.h>
	36	#include <linux/timer.h>
	37	#include <linux/uaccess.h>
	38	#include <linux/watchdog.h>
	39
	40	#define WDOG_CONTROL_REG_OFFSET 0x00
	41	#define WDOG_CONTROL_REG_WDT_EN_MASK 0x01
	42	#define WDOG_TIMEOUT_RANGE_REG_OFFSET 0x04
dfa07141	43	#define WDOG_TIMEOUT_RANGE_TOPINIT_SHIFT 4
c9353ae1 JI	44	#define WDOG_CURRENT_COUNT_REG_OFFSET 0x08
	45	#define WDOG_COUNTER_RESTART_REG_OFFSET 0x0c
	46	#define WDOG_COUNTER_RESTART_KICK_VALUE 0x76
	47
	48	/* The maximum TOP (timeout period) value that can be set in the watchdog. */
	49	#define DW_WDT_MAX_TOP 15
	50
86a1e189 WVS	51	static bool nowayout = WATCHDOG_NOWAYOUT;
86a1e189 WVS	52	module_param(nowayout, bool, 0);
c9353ae1 JI	53	MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started "
	54	"(default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
	55
	56	#define WDT_TIMEOUT (HZ / 2)
	57
	58	static struct {
	59	spinlock_t lock;
	60	void __iomem *regs;
	61	struct clk *clk;
	62	unsigned long in_use;
	63	unsigned long next_heartbeat;
	64	struct timer_list timer;
	65	int expect_close;
	66	} dw_wdt;
	67
	68	static inline int dw_wdt_is_enabled(void)
	69	{
	70	return readl(dw_wdt.regs + WDOG_CONTROL_REG_OFFSET) &
	71	WDOG_CONTROL_REG_WDT_EN_MASK;
	72	}
	73
	74	static inline int dw_wdt_top_in_seconds(unsigned top)
	75	{
	76	/*
	77	* There are 16 possible timeout values in 0..15 where the number of
	78	* cycles is 2 ^ (16 + i) and the watchdog counts down.
	79	*/
	80	return (1 << (16 + top)) / clk_get_rate(dw_wdt.clk);
	81	}
	82
	83	static int dw_wdt_get_top(void)
	84	{
	85	int top = readl(dw_wdt.regs + WDOG_TIMEOUT_RANGE_REG_OFFSET) & 0xF;
	86
	87	return dw_wdt_top_in_seconds(top);
	88	}
	89
	90	static inline void dw_wdt_set_next_heartbeat(void)
	91	{
	92	dw_wdt.next_heartbeat = jiffies + dw_wdt_get_top() * HZ;
	93	}
	94
	95	static int dw_wdt_set_top(unsigned top_s)
	96	{
	97	int i, top_val = DW_WDT_MAX_TOP;
	98
	99	/*
	100	* Iterate over the timeout values until we find the closest match. We
	101	* always look for >=.
	102	*/
	103	for (i = 0; i <= DW_WDT_MAX_TOP; ++i)
	104	if (dw_wdt_top_in_seconds(i) >= top_s) {
	105	top_val = i;
	106	break;
	107	}
	108
	109	/* Set the new value in the watchdog. */
dfa07141 JZ	110	writel(top_val \| top_val << WDOG_TIMEOUT_RANGE_TOPINIT_SHIFT,
dfa07141 JZ	111	dw_wdt.regs + WDOG_TIMEOUT_RANGE_REG_OFFSET);
c9353ae1 JI	112
	113	dw_wdt_set_next_heartbeat();
	114
	115	return dw_wdt_top_in_seconds(top_val);
	116	}
	117
	118	static void dw_wdt_keepalive(void)
	119	{
	120	writel(WDOG_COUNTER_RESTART_KICK_VALUE, dw_wdt.regs +
	121	WDOG_COUNTER_RESTART_REG_OFFSET);
	122	}
	123
	124	static void dw_wdt_ping(unsigned long data)
	125	{
	126	if (time_before(jiffies, dw_wdt.next_heartbeat) \|\|
	127	(!nowayout && !dw_wdt.in_use)) {
	128	dw_wdt_keepalive();
	129	mod_timer(&dw_wdt.timer, jiffies + WDT_TIMEOUT);
	130	} else
	131	pr_crit("keepalive missed, machine will reset\n");
	132	}
	133
	134	static int dw_wdt_open(struct inode inode, struct file filp)
	135	{
	136	if (test_and_set_bit(0, &dw_wdt.in_use))
	137	return -EBUSY;
	138
	139	/* Make sure we don't get unloaded. */
	140	__module_get(THIS_MODULE);
	141
	142	spin_lock(&dw_wdt.lock);
	143	if (!dw_wdt_is_enabled()) {
	144	/*
	145	* The watchdog is not currently enabled. Set the timeout to
	146	* the maximum and then start it.
	147	*/
	148	dw_wdt_set_top(DW_WDT_MAX_TOP);
	149	writel(WDOG_CONTROL_REG_WDT_EN_MASK,
	150	dw_wdt.regs + WDOG_CONTROL_REG_OFFSET);
	151	}
	152
	153	dw_wdt_set_next_heartbeat();
	154
	155	spin_unlock(&dw_wdt.lock);
	156
	157	return nonseekable_open(inode, filp);
	158	}
	159
0b930261 SK	160	static ssize_t dw_wdt_write(struct file filp, const char __user buf,
0b930261 SK	161	size_t len, loff_t *offset)
c9353ae1 JI	162	{
	163	if (!len)
	164	return 0;
	165
	166	if (!nowayout) {
	167	size_t i;
	168
	169	dw_wdt.expect_close = 0;
	170
	171	for (i = 0; i < len; ++i) {
	172	char c;
	173
	174	if (get_user(c, buf + i))
	175	return -EFAULT;
	176
	177	if (c == 'V') {
	178	dw_wdt.expect_close = 1;
	179	break;
	180	}
	181	}
	182	}
	183
	184	dw_wdt_set_next_heartbeat();
	185	mod_timer(&dw_wdt.timer, jiffies + WDT_TIMEOUT);
	186
	187	return len;
	188	}
	189
	190	static u32 dw_wdt_time_left(void)
	191	{
	192	return readl(dw_wdt.regs + WDOG_CURRENT_COUNT_REG_OFFSET) /
	193	clk_get_rate(dw_wdt.clk);
	194	}
	195
	196	static const struct watchdog_info dw_wdt_ident = {
	197	.options = WDIOF_KEEPALIVEPING \| WDIOF_SETTIMEOUT \|
	198	WDIOF_MAGICCLOSE,
	199	.identity = "Synopsys DesignWare Watchdog",
	200	};
	201
	202	static long dw_wdt_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
	203	{
	204	unsigned long val;
	205	int timeout;
	206
	207	switch (cmd) {
	208	case WDIOC_GETSUPPORT:
60295507	209	return copy_to_user((void __user *)arg, &dw_wdt_ident,
c9353ae1 JI	210	sizeof(dw_wdt_ident)) ? -EFAULT : 0;
	211
	212	case WDIOC_GETSTATUS:
	213	case WDIOC_GETBOOTSTATUS:
60295507	214	return put_user(0, (int __user *)arg);
c9353ae1 JI	215
	216	case WDIOC_KEEPALIVE:
	217	dw_wdt_set_next_heartbeat();
	218	return 0;
	219
	220	case WDIOC_SETTIMEOUT:
	221	if (get_user(val, (int __user *)arg))
	222	return -EFAULT;
	223	timeout = dw_wdt_set_top(val);
	224	return put_user(timeout , (int __user *)arg);
	225
	226	case WDIOC_GETTIMEOUT:
	227	return put_user(dw_wdt_get_top(), (int __user *)arg);
	228
	229	case WDIOC_GETTIMELEFT:
	230	/* Get the time left until expiry. */
	231	if (get_user(val, (int __user *)arg))
	232	return -EFAULT;
	233	return put_user(dw_wdt_time_left(), (int __user *)arg);
	234
	235	default:
	236	return -ENOTTY;
	237	}
	238	}
	239
	240	static int dw_wdt_release(struct inode inode, struct file filp)
	241	{
	242	clear_bit(0, &dw_wdt.in_use);
	243
	244	if (!dw_wdt.expect_close) {
	245	del_timer(&dw_wdt.timer);
	246
	247	if (!nowayout)
	248	pr_crit("unexpected close, system will reboot soon\n");
	249	else
	250	pr_crit("watchdog cannot be disabled, system will reboot soon\n");
	251	}
	252
	253	dw_wdt.expect_close = 0;
	254
	255	return 0;
	256	}
	257
ad83c6cb	258	#ifdef CONFIG_PM_SLEEP
c9353ae1 JI	259	static int dw_wdt_suspend(struct device *dev)
c9353ae1 JI	260	{
280103e6	261	clk_disable_unprepare(dw_wdt.clk);
c9353ae1 JI	262
	263	return 0;
	264	}
	265
	266	static int dw_wdt_resume(struct device *dev)
	267	{
280103e6	268	int err = clk_prepare_enable(dw_wdt.clk);
c9353ae1 JI	269
	270	if (err)
	271	return err;
	272
	273	dw_wdt_keepalive();
	274
	275	return 0;
	276	}
ad83c6cb	277	#endif /* CONFIG_PM_SLEEP */
c9353ae1	278
ad83c6cb	279	static SIMPLE_DEV_PM_OPS(dw_wdt_pm_ops, dw_wdt_suspend, dw_wdt_resume);
c9353ae1 JI	280
	281	static const struct file_operations wdt_fops = {
	282	.owner = THIS_MODULE,
	283	.llseek = no_llseek,
	284	.open = dw_wdt_open,
	285	.write = dw_wdt_write,
	286	.unlocked_ioctl = dw_wdt_ioctl,
	287	.release = dw_wdt_release
	288	};
	289
	290	static struct miscdevice dw_wdt_miscdev = {
	291	.fops = &wdt_fops,
	292	.name = "watchdog",
	293	.minor = WATCHDOG_MINOR,
	294	};
	295
2d991a16	296	static int dw_wdt_drv_probe(struct platform_device *pdev)
c9353ae1 JI	297	{
	298	int ret;
	299	struct resource *mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	300
4c271bb6 TR	301	dw_wdt.regs = devm_ioremap_resource(&pdev->dev, mem);
	302	if (IS_ERR(dw_wdt.regs))
	303	return PTR_ERR(dw_wdt.regs);
c9353ae1	304
cf3cc8c2	305	dw_wdt.clk = devm_clk_get(&pdev->dev, NULL);
c9353ae1 JI	306	if (IS_ERR(dw_wdt.clk))
	307	return PTR_ERR(dw_wdt.clk);
	308
280103e6	309	ret = clk_prepare_enable(dw_wdt.clk);
c9353ae1	310	if (ret)
cf3cc8c2	311	return ret;
c9353ae1 JI	312
	313	spin_lock_init(&dw_wdt.lock);
	314
	315	ret = misc_register(&dw_wdt_miscdev);
	316	if (ret)
	317	goto out_disable_clk;
	318
	319	dw_wdt_set_next_heartbeat();
	320	setup_timer(&dw_wdt.timer, dw_wdt_ping, 0);
	321	mod_timer(&dw_wdt.timer, jiffies + WDT_TIMEOUT);
	322
	323	return 0;
	324
	325	out_disable_clk:
280103e6	326	clk_disable_unprepare(dw_wdt.clk);
c9353ae1 JI	327
	328	return ret;
	329	}
	330
4b12b896	331	static int dw_wdt_drv_remove(struct platform_device *pdev)
c9353ae1 JI	332	{
	333	misc_deregister(&dw_wdt_miscdev);
	334
280103e6	335	clk_disable_unprepare(dw_wdt.clk);
c9353ae1 JI	336
	337	return 0;
	338	}
	339
58e56373 DN	340	#ifdef CONFIG_OF
	341	static const struct of_device_id dw_wdt_of_match[] = {
	342	{ .compatible = "snps,dw-wdt", },
	343	{ /* sentinel */ }
	344	};
	345	MODULE_DEVICE_TABLE(of, dw_wdt_of_match);
	346	#endif
	347
c9353ae1 JI	348	static struct platform_driver dw_wdt_driver = {
c9353ae1 JI	349	.probe = dw_wdt_drv_probe,
82268714	350	.remove = dw_wdt_drv_remove,
c9353ae1 JI	351	.driver = {
	352	.name = "dw_wdt",
	353	.owner = THIS_MODULE,
58e56373	354	.of_match_table = of_match_ptr(dw_wdt_of_match),
c9353ae1	355	.pm = &dw_wdt_pm_ops,
c9353ae1 JI	356	},
	357	};
	358
b8ec6118	359	module_platform_driver(dw_wdt_driver);
c9353ae1 JI	360
	361	MODULE_AUTHOR("Jamie Iles");
	362	MODULE_DESCRIPTION("Synopsys DesignWare Watchdog Driver");
	363	MODULE_LICENSE("GPL");