[net-next-2.6.git] / drivers / watchdog / rdc321x_wdt.c

/*
 * RDC321x watchdog driver
 *
 * Copyright (C) 2007-2010 Florian Fainelli <florian@openwrt.org>
 *
 * This driver is highly inspired from the cpu5_wdt driver
 *
 * 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 program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 */

#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/miscdevice.h>
#include <linux/fs.h>
#include <linux/init.h>
#include <linux/ioport.h>
#include <linux/timer.h>
#include <linux/completion.h>
#include <linux/jiffies.h>
#include <linux/platform_device.h>
#include <linux/watchdog.h>
#include <linux/io.h>
#include <linux/uaccess.h>
#include <linux/mfd/rdc321x.h>

#define RDC_WDT_MASK	0x80000000 /* Mask */
#define RDC_WDT_EN	0x00800000 /* Enable bit */
#define RDC_WDT_WTI	0x00200000 /* Generate CPU reset/NMI/WDT on timeout */
#define RDC_WDT_RST	0x00100000 /* Reset bit */
#define RDC_WDT_WIF	0x00040000 /* WDT IRQ Flag */
#define RDC_WDT_IRT	0x00000100 /* IRQ Routing table */
#define RDC_WDT_CNT	0x00000001 /* WDT count */

#define RDC_CLS_TMR	0x80003844 /* Clear timer */

#define RDC_WDT_INTERVAL	(HZ/10+1)

static int ticks = 1000;

/* some device data */

static struct {
	struct completion stop;
	int running;
	struct timer_list timer;
	int queue;
	int default_ticks;
	unsigned long inuse;
	spinlock_t lock;
	struct pci_dev *sb_pdev;
	int base_reg;
} rdc321x_wdt_device;

/* generic helper functions */

static void rdc321x_wdt_trigger(unsigned long unused)
{
	unsigned long flags;
	u32 val;

	if (rdc321x_wdt_device.running)
		ticks--;

	/* keep watchdog alive */
	spin_lock_irqsave(&rdc321x_wdt_device.lock, flags);
	pci_read_config_dword(rdc321x_wdt_device.sb_pdev,
					rdc321x_wdt_device.base_reg, &val);
	val |= RDC_WDT_EN;
	pci_write_config_dword(rdc321x_wdt_device.sb_pdev,
					rdc321x_wdt_device.base_reg, val);
	spin_unlock_irqrestore(&rdc321x_wdt_device.lock, flags);

	/* requeue?? */
	if (rdc321x_wdt_device.queue && ticks)
		mod_timer(&rdc321x_wdt_device.timer,
				jiffies + RDC_WDT_INTERVAL);
	else {
		/* ticks doesn't matter anyway */
		complete(&rdc321x_wdt_device.stop);
	}

}

static void rdc321x_wdt_reset(void)
{
	ticks = rdc321x_wdt_device.default_ticks;
}

static void rdc321x_wdt_start(void)
{
	unsigned long flags;

	if (!rdc321x_wdt_device.queue) {
		rdc321x_wdt_device.queue = 1;

		/* Clear the timer */
		spin_lock_irqsave(&rdc321x_wdt_device.lock, flags);
		pci_write_config_dword(rdc321x_wdt_device.sb_pdev,
				rdc321x_wdt_device.base_reg, RDC_CLS_TMR);

		/* Enable watchdog and set the timeout to 81.92 us */
		pci_write_config_dword(rdc321x_wdt_device.sb_pdev,
					rdc321x_wdt_device.base_reg,
					RDC_WDT_EN | RDC_WDT_CNT);
		spin_unlock_irqrestore(&rdc321x_wdt_device.lock, flags);

		mod_timer(&rdc321x_wdt_device.timer,
				jiffies + RDC_WDT_INTERVAL);
	}

	/* if process dies, counter is not decremented */
	rdc321x_wdt_device.running++;
}

static int rdc321x_wdt_stop(void)
{
	if (rdc321x_wdt_device.running)
		rdc321x_wdt_device.running = 0;

	ticks = rdc321x_wdt_device.default_ticks;

	return -EIO;
}

/* filesystem operations */
static int rdc321x_wdt_open(struct inode *inode, struct file *file)
{
	if (test_and_set_bit(0, &rdc321x_wdt_device.inuse))
		return -EBUSY;

	return nonseekable_open(inode, file);
}

static int rdc321x_wdt_release(struct inode *inode, struct file *file)
{
	clear_bit(0, &rdc321x_wdt_device.inuse);
	return 0;
}

static long rdc321x_wdt_ioctl(struct file *file, unsigned int cmd,
				unsigned long arg)
{
	void __user *argp = (void __user *)arg;
	u32 value;
	static const struct watchdog_info ident = {
		.options = WDIOF_CARDRESET,
		.identity = "RDC321x WDT",
	};
	unsigned long flags;

	switch (cmd) {
	case WDIOC_KEEPALIVE:
		rdc321x_wdt_reset();
		break;
	case WDIOC_GETSTATUS:
		/* Read the value from the DATA register */
		spin_lock_irqsave(&rdc321x_wdt_device.lock, flags);
		pci_read_config_dword(rdc321x_wdt_device.sb_pdev,
					rdc321x_wdt_device.base_reg, &value);
		spin_unlock_irqrestore(&rdc321x_wdt_device.lock, flags);
		if (copy_to_user(argp, &value, sizeof(u32)))
			return -EFAULT;
		break;
	case WDIOC_GETSUPPORT:
		if (copy_to_user(argp, &ident, sizeof(ident)))
			return -EFAULT;
		break;
	case WDIOC_SETOPTIONS:
		if (copy_from_user(&value, argp, sizeof(int)))
			return -EFAULT;
		switch (value) {
		case WDIOS_ENABLECARD:
			rdc321x_wdt_start();
			break;
		case WDIOS_DISABLECARD:
			return rdc321x_wdt_stop();
		default:
			return -EINVAL;
		}
		break;
	default:
		return -ENOTTY;
	}
	return 0;
}

static ssize_t rdc321x_wdt_write(struct file *file, const char __user *buf,
				size_t count, loff_t *ppos)
{
	if (!count)
		return -EIO;

	rdc321x_wdt_reset();

	return count;
}

static const struct file_operations rdc321x_wdt_fops = {
	.owner		= THIS_MODULE,
	.llseek		= no_llseek,
	.unlocked_ioctl	= rdc321x_wdt_ioctl,
	.open		= rdc321x_wdt_open,
	.write		= rdc321x_wdt_write,
	.release	= rdc321x_wdt_release,
};

static struct miscdevice rdc321x_wdt_misc = {
	.minor	= WATCHDOG_MINOR,
	.name	= "watchdog",
	.fops	= &rdc321x_wdt_fops,
};

static int __devinit rdc321x_wdt_probe(struct platform_device *pdev)
{
	int err;
	struct resource *r;
	struct rdc321x_wdt_pdata *pdata;

	pdata = pdev->dev.platform_data;
	if (!pdata) {
		dev_err(&pdev->dev, "no platform data supplied\n");
		return -ENODEV;
	}

	r = platform_get_resource_byname(pdev, IORESOURCE_IO, "wdt-reg");
	if (!r) {
		dev_err(&pdev->dev, "failed to get wdt-reg resource\n");
		return -ENODEV;
	}

	rdc321x_wdt_device.sb_pdev = pdata->sb_pdev;
	rdc321x_wdt_device.base_reg = r->start;

	err = misc_register(&rdc321x_wdt_misc);
	if (err < 0) {
		dev_err(&pdev->dev, "misc_register failed\n");
		return err;
	}

	spin_lock_init(&rdc321x_wdt_device.lock);

	/* Reset the watchdog */
	pci_write_config_dword(rdc321x_wdt_device.sb_pdev,
				rdc321x_wdt_device.base_reg, RDC_WDT_RST);

	init_completion(&rdc321x_wdt_device.stop);
	rdc321x_wdt_device.queue = 0;

	clear_bit(0, &rdc321x_wdt_device.inuse);

	setup_timer(&rdc321x_wdt_device.timer, rdc321x_wdt_trigger, 0);

	rdc321x_wdt_device.default_ticks = ticks;

	dev_info(&pdev->dev, "watchdog init success\n");

	return 0;
}

static int __devexit rdc321x_wdt_remove(struct platform_device *pdev)
{
	if (rdc321x_wdt_device.queue) {
		rdc321x_wdt_device.queue = 0;
		wait_for_completion(&rdc321x_wdt_device.stop);
	}

	misc_deregister(&rdc321x_wdt_misc);

	return 0;
}

static struct platform_driver rdc321x_wdt_driver = {
	.probe = rdc321x_wdt_probe,
	.remove = __devexit_p(rdc321x_wdt_remove),
	.driver = {
		.owner = THIS_MODULE,
		.name = "rdc321x-wdt",
	},
};

static int __init rdc321x_wdt_init(void)
{
	return platform_driver_register(&rdc321x_wdt_driver);
}

static void __exit rdc321x_wdt_exit(void)
{
	platform_driver_unregister(&rdc321x_wdt_driver);
}

module_init(rdc321x_wdt_init);
module_exit(rdc321x_wdt_exit);

MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
MODULE_DESCRIPTION("RDC321x watchdog driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
Commit	Line	Data
b3e8f2c1 FF	1	/*
	2	* RDC321x watchdog driver
	3	*
842102f3	4	* Copyright (C) 2007-2010 Florian Fainelli <florian@openwrt.org>
b3e8f2c1 FF	5	*
	6	* This driver is highly inspired from the cpu5_wdt driver
	7	*
	8	* This program is free software; you can redistribute it and/or modify
	9	* it under the terms of the GNU General Public License as published by
	10	* the Free Software Foundation; either version 2 of the License, or
	11	* (at your option) any later version.
	12	*
	13	* This program is distributed in the hope that it will be useful,
	14	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	15	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	16	* GNU General Public License for more details.
	17	*
	18	* You should have received a copy of the GNU General Public License
	19	* along with this program; if not, write to the Free Software
	20	* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
	21	*
	22	*/
	23
	24	#include <linux/module.h>
	25	#include <linux/moduleparam.h>
	26	#include <linux/types.h>
	27	#include <linux/errno.h>
	28	#include <linux/miscdevice.h>
	29	#include <linux/fs.h>
	30	#include <linux/init.h>
	31	#include <linux/ioport.h>
	32	#include <linux/timer.h>
	33	#include <linux/completion.h>
	34	#include <linux/jiffies.h>
	35	#include <linux/platform_device.h>
	36	#include <linux/watchdog.h>
	37	#include <linux/io.h>
	38	#include <linux/uaccess.h>
842102f3	39	#include <linux/mfd/rdc321x.h>
b3e8f2c1 FF	40
	41	#define RDC_WDT_MASK 0x80000000 /* Mask */
	42	#define RDC_WDT_EN 0x00800000 /* Enable bit */
	43	#define RDC_WDT_WTI 0x00200000 /* Generate CPU reset/NMI/WDT on timeout */
	44	#define RDC_WDT_RST 0x00100000 /* Reset bit */
	45	#define RDC_WDT_WIF 0x00040000 /* WDT IRQ Flag */
	46	#define RDC_WDT_IRT 0x00000100 /* IRQ Routing table */
	47	#define RDC_WDT_CNT 0x00000001 /* WDT count */
	48
	49	#define RDC_CLS_TMR 0x80003844 /* Clear timer */
	50
	51	#define RDC_WDT_INTERVAL (HZ/10+1)
	52
	53	static int ticks = 1000;
	54
	55	/* some device data */
	56
	57	static struct {
	58	struct completion stop;
	59	int running;
	60	struct timer_list timer;
	61	int queue;
	62	int default_ticks;
	63	unsigned long inuse;
	64	spinlock_t lock;
842102f3 FF	65	struct pci_dev *sb_pdev;
842102f3 FF	66	int base_reg;
b3e8f2c1 FF	67	} rdc321x_wdt_device;
	68
	69	/* generic helper functions */
	70
	71	static void rdc321x_wdt_trigger(unsigned long unused)
	72	{
	73	unsigned long flags;
842102f3	74	u32 val;
b3e8f2c1 FF	75
	76	if (rdc321x_wdt_device.running)
	77	ticks--;
	78
	79	/* keep watchdog alive */
	80	spin_lock_irqsave(&rdc321x_wdt_device.lock, flags);
842102f3 FF	81	pci_read_config_dword(rdc321x_wdt_device.sb_pdev,
	82	rdc321x_wdt_device.base_reg, &val);
	83	val \|= RDC_WDT_EN;
	84	pci_write_config_dword(rdc321x_wdt_device.sb_pdev,
	85	rdc321x_wdt_device.base_reg, val);
b3e8f2c1 FF	86	spin_unlock_irqrestore(&rdc321x_wdt_device.lock, flags);
	87
	88	/* requeue?? */
	89	if (rdc321x_wdt_device.queue && ticks)
	90	mod_timer(&rdc321x_wdt_device.timer,
	91	jiffies + RDC_WDT_INTERVAL);
	92	else {
	93	/* ticks doesn't matter anyway */
	94	complete(&rdc321x_wdt_device.stop);
	95	}
	96
	97	}
	98
	99	static void rdc321x_wdt_reset(void)
	100	{
	101	ticks = rdc321x_wdt_device.default_ticks;
	102	}
	103
	104	static void rdc321x_wdt_start(void)
	105	{
	106	unsigned long flags;
	107
	108	if (!rdc321x_wdt_device.queue) {
	109	rdc321x_wdt_device.queue = 1;
	110
	111	/* Clear the timer */
	112	spin_lock_irqsave(&rdc321x_wdt_device.lock, flags);
842102f3 FF	113	pci_write_config_dword(rdc321x_wdt_device.sb_pdev,
842102f3 FF	114	rdc321x_wdt_device.base_reg, RDC_CLS_TMR);
b3e8f2c1 FF	115
b3e8f2c1 FF	116	/* Enable watchdog and set the timeout to 81.92 us */
842102f3 FF	117	pci_write_config_dword(rdc321x_wdt_device.sb_pdev,
	118	rdc321x_wdt_device.base_reg,
	119	RDC_WDT_EN \| RDC_WDT_CNT);
b3e8f2c1 FF	120	spin_unlock_irqrestore(&rdc321x_wdt_device.lock, flags);
	121
	122	mod_timer(&rdc321x_wdt_device.timer,
	123	jiffies + RDC_WDT_INTERVAL);
	124	}
	125
	126	/* if process dies, counter is not decremented */
	127	rdc321x_wdt_device.running++;
	128	}
	129
	130	static int rdc321x_wdt_stop(void)
	131	{
	132	if (rdc321x_wdt_device.running)
	133	rdc321x_wdt_device.running = 0;
	134
	135	ticks = rdc321x_wdt_device.default_ticks;
	136
	137	return -EIO;
	138	}
	139
	140	/* filesystem operations */
	141	static int rdc321x_wdt_open(struct inode inode, struct file file)
	142	{
	143	if (test_and_set_bit(0, &rdc321x_wdt_device.inuse))
	144	return -EBUSY;
	145
	146	return nonseekable_open(inode, file);
	147	}
	148
	149	static int rdc321x_wdt_release(struct inode inode, struct file file)
	150	{
	151	clear_bit(0, &rdc321x_wdt_device.inuse);
	152	return 0;
	153	}
	154
7275fc8c WVS	155	static long rdc321x_wdt_ioctl(struct file *file, unsigned int cmd,
7275fc8c WVS	156	unsigned long arg)
b3e8f2c1 FF	157	{
b3e8f2c1 FF	158	void __user argp = (void __user )arg;
842102f3	159	u32 value;
42747d71	160	static const struct watchdog_info ident = {
b3e8f2c1 FF	161	.options = WDIOF_CARDRESET,
	162	.identity = "RDC321x WDT",
	163	};
	164	unsigned long flags;
	165
	166	switch (cmd) {
	167	case WDIOC_KEEPALIVE:
	168	rdc321x_wdt_reset();
	169	break;
	170	case WDIOC_GETSTATUS:
	171	/* Read the value from the DATA register */
	172	spin_lock_irqsave(&rdc321x_wdt_device.lock, flags);
842102f3 FF	173	pci_read_config_dword(rdc321x_wdt_device.sb_pdev,
842102f3 FF	174	rdc321x_wdt_device.base_reg, &value);
b3e8f2c1	175	spin_unlock_irqrestore(&rdc321x_wdt_device.lock, flags);
842102f3	176	if (copy_to_user(argp, &value, sizeof(u32)))
b3e8f2c1 FF	177	return -EFAULT;
	178	break;
	179	case WDIOC_GETSUPPORT:
	180	if (copy_to_user(argp, &ident, sizeof(ident)))
	181	return -EFAULT;
	182	break;
	183	case WDIOC_SETOPTIONS:
	184	if (copy_from_user(&value, argp, sizeof(int)))
	185	return -EFAULT;
	186	switch (value) {
	187	case WDIOS_ENABLECARD:
	188	rdc321x_wdt_start();
	189	break;
	190	case WDIOS_DISABLECARD:
	191	return rdc321x_wdt_stop();
	192	default:
	193	return -EINVAL;
	194	}
	195	break;
	196	default:
	197	return -ENOTTY;
	198	}
	199	return 0;
	200	}
	201
	202	static ssize_t rdc321x_wdt_write(struct file file, const char __user buf,
	203	size_t count, loff_t *ppos)
	204	{
	205	if (!count)
	206	return -EIO;
	207
	208	rdc321x_wdt_reset();
	209
	210	return count;
	211	}
	212
	213	static const struct file_operations rdc321x_wdt_fops = {
	214	.owner = THIS_MODULE,
	215	.llseek = no_llseek,
7275fc8c	216	.unlocked_ioctl = rdc321x_wdt_ioctl,
b3e8f2c1 FF	217	.open = rdc321x_wdt_open,
	218	.write = rdc321x_wdt_write,
	219	.release = rdc321x_wdt_release,
	220	};
	221
	222	static struct miscdevice rdc321x_wdt_misc = {
	223	.minor = WATCHDOG_MINOR,
	224	.name = "watchdog",
	225	.fops = &rdc321x_wdt_fops,
	226	};
	227
	228	static int __devinit rdc321x_wdt_probe(struct platform_device *pdev)
	229	{
	230	int err;
842102f3 FF	231	struct resource *r;
	232	struct rdc321x_wdt_pdata *pdata;
	233
	234	pdata = pdev->dev.platform_data;
	235	if (!pdata) {
	236	dev_err(&pdev->dev, "no platform data supplied\n");
	237	return -ENODEV;
	238	}
	239
8deca39e	240	r = platform_get_resource_byname(pdev, IORESOURCE_IO, "wdt-reg");
842102f3 FF	241	if (!r) {
	242	dev_err(&pdev->dev, "failed to get wdt-reg resource\n");
	243	return -ENODEV;
	244	}
	245
	246	rdc321x_wdt_device.sb_pdev = pdata->sb_pdev;
	247	rdc321x_wdt_device.base_reg = r->start;
b3e8f2c1 FF	248
	249	err = misc_register(&rdc321x_wdt_misc);
	250	if (err < 0) {
842102f3	251	dev_err(&pdev->dev, "misc_register failed\n");
b3e8f2c1 FF	252	return err;
	253	}
	254
	255	spin_lock_init(&rdc321x_wdt_device.lock);
	256
	257	/* Reset the watchdog */
842102f3 FF	258	pci_write_config_dword(rdc321x_wdt_device.sb_pdev,
842102f3 FF	259	rdc321x_wdt_device.base_reg, RDC_WDT_RST);
b3e8f2c1 FF	260
	261	init_completion(&rdc321x_wdt_device.stop);
	262	rdc321x_wdt_device.queue = 0;
	263
	264	clear_bit(0, &rdc321x_wdt_device.inuse);
	265
	266	setup_timer(&rdc321x_wdt_device.timer, rdc321x_wdt_trigger, 0);
	267
	268	rdc321x_wdt_device.default_ticks = ticks;
	269
842102f3	270	dev_info(&pdev->dev, "watchdog init success\n");
b3e8f2c1 FF	271
	272	return 0;
	273	}
	274
b6bf291f	275	static int __devexit rdc321x_wdt_remove(struct platform_device *pdev)
b3e8f2c1 FF	276	{
	277	if (rdc321x_wdt_device.queue) {
	278	rdc321x_wdt_device.queue = 0;
	279	wait_for_completion(&rdc321x_wdt_device.stop);
	280	}
	281
	282	misc_deregister(&rdc321x_wdt_misc);
	283
	284	return 0;
	285	}
	286
	287	static struct platform_driver rdc321x_wdt_driver = {
	288	.probe = rdc321x_wdt_probe,
b6bf291f	289	.remove = __devexit_p(rdc321x_wdt_remove),
b3e8f2c1 FF	290	.driver = {
	291	.owner = THIS_MODULE,
	292	.name = "rdc321x-wdt",
	293	},
	294	};
	295
	296	static int __init rdc321x_wdt_init(void)
	297	{
	298	return platform_driver_register(&rdc321x_wdt_driver);
	299	}
	300
	301	static void __exit rdc321x_wdt_exit(void)
	302	{
	303	platform_driver_unregister(&rdc321x_wdt_driver);
	304	}
	305
	306	module_init(rdc321x_wdt_init);
	307	module_exit(rdc321x_wdt_exit);
	308
	309	MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
	310	MODULE_DESCRIPTION("RDC321x watchdog driver");
	311	MODULE_LICENSE("GPL");
	312	MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);