[net-next-2.6.git] / drivers / watchdog / cpu5wdt.c

/*
 * sma cpu5 watchdog driver
 *
 * Copyright (C) 2003 Heiko Ronsdorf <hero@ihg.uni-duisburg.de>
 *
 * 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/io.h>
#include <linux/uaccess.h>
#include <linux/watchdog.h>

/* adjustable parameters */

static int verbose;
static int port = 0x91;
static int ticks = 10000;
static spinlock_t cpu5wdt_lock;

#define PFX			"cpu5wdt: "

#define CPU5WDT_EXTENT          0x0A

#define CPU5WDT_STATUS_REG      0x00
#define CPU5WDT_TIME_A_REG      0x02
#define CPU5WDT_TIME_B_REG      0x03
#define CPU5WDT_MODE_REG        0x04
#define CPU5WDT_TRIGGER_REG     0x07
#define CPU5WDT_ENABLE_REG      0x08
#define CPU5WDT_RESET_REG       0x09

#define CPU5WDT_INTERVAL	(HZ/10+1)

/* some device data */

static struct {
	struct completion stop;
	int running;
	struct timer_list timer;
	int queue;
	int default_ticks;
	unsigned long inuse;
} cpu5wdt_device;

/* generic helper functions */

static void cpu5wdt_trigger(unsigned long unused)
{
	if (verbose > 2)
		printk(KERN_DEBUG PFX "trigger at %i ticks\n", ticks);

	if (cpu5wdt_device.running)
		ticks--;

	spin_lock(&cpu5wdt_lock);
	/* keep watchdog alive */
	outb(1, port + CPU5WDT_TRIGGER_REG);

	/* requeue?? */
	if (cpu5wdt_device.queue && ticks)
		mod_timer(&cpu5wdt_device.timer, jiffies + CPU5WDT_INTERVAL);
	else {
		/* ticks doesn't matter anyway */
		complete(&cpu5wdt_device.stop);
	}
	spin_unlock(&cpu5wdt_lock);

}

static void cpu5wdt_reset(void)
{
	ticks = cpu5wdt_device.default_ticks;

	if (verbose)
		printk(KERN_DEBUG PFX "reset (%i ticks)\n", (int) ticks);

}

static void cpu5wdt_start(void)
{
	unsigned long flags;

	spin_lock_irqsave(&cpu5wdt_lock, flags);
	if (!cpu5wdt_device.queue) {
		cpu5wdt_device.queue = 1;
		outb(0, port + CPU5WDT_TIME_A_REG);
		outb(0, port + CPU5WDT_TIME_B_REG);
		outb(1, port + CPU5WDT_MODE_REG);
		outb(0, port + CPU5WDT_RESET_REG);
		outb(0, port + CPU5WDT_ENABLE_REG);
		mod_timer(&cpu5wdt_device.timer, jiffies + CPU5WDT_INTERVAL);
	}
	/* if process dies, counter is not decremented */
	cpu5wdt_device.running++;
	spin_unlock_irqrestore(&cpu5wdt_lock, flags);
}

static int cpu5wdt_stop(void)
{
	unsigned long flags;

	spin_lock_irqsave(&cpu5wdt_lock, flags);
	if (cpu5wdt_device.running)
		cpu5wdt_device.running = 0;
	ticks = cpu5wdt_device.default_ticks;
	spin_unlock_irqrestore(&cpu5wdt_lock, flags);
	if (verbose)
		printk(KERN_CRIT PFX "stop not possible\n");
	return -EIO;
}

/* filesystem operations */

static int cpu5wdt_open(struct inode *inode, struct file *file)
{
	if (test_and_set_bit(0, &cpu5wdt_device.inuse))
		return -EBUSY;
	return nonseekable_open(inode, file);
}

static int cpu5wdt_release(struct inode *inode, struct file *file)
{
	clear_bit(0, &cpu5wdt_device.inuse);
	return 0;
}

static long cpu5wdt_ioctl(struct file *file, unsigned int cmd,
						unsigned long arg)
{
	void __user *argp = (void __user *)arg;
	int __user *p = argp;
	unsigned int value;
	static const struct watchdog_info ident = {
		.options = WDIOF_CARDRESET,
		.identity = "CPU5 WDT",
	};

	switch (cmd) {
	case WDIOC_GETSUPPORT:
		if (copy_to_user(argp, &ident, sizeof(ident)))
			return -EFAULT;
		break;
	case WDIOC_GETSTATUS:
		value = inb(port + CPU5WDT_STATUS_REG);
		value = (value >> 2) & 1;
		return put_user(value, p);
	case WDIOC_GETBOOTSTATUS:
		return put_user(0, p);
	case WDIOC_SETOPTIONS:
		if (get_user(value, p))
			return -EFAULT;
		if (value & WDIOS_ENABLECARD)
			cpu5wdt_start();
		if (value & WDIOS_DISABLECARD)
			cpu5wdt_stop();
		break;
	case WDIOC_KEEPALIVE:
		cpu5wdt_reset();
		break;
	default:
		return -ENOTTY;
	}
	return 0;
}

static ssize_t cpu5wdt_write(struct file *file, const char __user *buf,
						size_t count, loff_t *ppos)
{
	if (!count)
		return -EIO;
	cpu5wdt_reset();
	return count;
}

static const struct file_operations cpu5wdt_fops = {
	.owner		= THIS_MODULE,
	.llseek		= no_llseek,
	.unlocked_ioctl	= cpu5wdt_ioctl,
	.open		= cpu5wdt_open,
	.write		= cpu5wdt_write,
	.release	= cpu5wdt_release,
};

static struct miscdevice cpu5wdt_misc = {
	.minor	= WATCHDOG_MINOR,
	.name	= "watchdog",
	.fops	= &cpu5wdt_fops,
};

/* init/exit function */

static int __devinit cpu5wdt_init(void)
{
	unsigned int val;
	int err;

	if (verbose)
		printk(KERN_DEBUG PFX
				"port=0x%x, verbose=%i\n", port, verbose);

	init_completion(&cpu5wdt_device.stop);
	spin_lock_init(&cpu5wdt_lock);
	cpu5wdt_device.queue = 0;
	setup_timer(&cpu5wdt_device.timer, cpu5wdt_trigger, 0);
	cpu5wdt_device.default_ticks = ticks;

	if (!request_region(port, CPU5WDT_EXTENT, PFX)) {
		printk(KERN_ERR PFX "request_region failed\n");
		err = -EBUSY;
		goto no_port;
	}

	/* watchdog reboot? */
	val = inb(port + CPU5WDT_STATUS_REG);
	val = (val >> 2) & 1;
	if (!val)
		printk(KERN_INFO PFX "sorry, was my fault\n");

	err = misc_register(&cpu5wdt_misc);
	if (err < 0) {
		printk(KERN_ERR PFX "misc_register failed\n");
		goto no_misc;
	}


	printk(KERN_INFO PFX "init success\n");
	return 0;

no_misc:
	release_region(port, CPU5WDT_EXTENT);
no_port:
	return err;
}

static int __devinit cpu5wdt_init_module(void)
{
	return cpu5wdt_init();
}

static void __devexit cpu5wdt_exit(void)
{
	if (cpu5wdt_device.queue) {
		cpu5wdt_device.queue = 0;
		wait_for_completion(&cpu5wdt_device.stop);
	}

	misc_deregister(&cpu5wdt_misc);

	release_region(port, CPU5WDT_EXTENT);

}

static void __devexit cpu5wdt_exit_module(void)
{
	cpu5wdt_exit();
}

/* module entry points */

module_init(cpu5wdt_init_module);
module_exit(cpu5wdt_exit_module);

MODULE_AUTHOR("Heiko Ronsdorf <hero@ihg.uni-duisburg.de>");
MODULE_DESCRIPTION("sma cpu5 watchdog driver");
MODULE_SUPPORTED_DEVICE("sma cpu5 watchdog");
MODULE_LICENSE("GPL");
MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);

module_param(port, int, 0);
MODULE_PARM_DESC(port, "base address of watchdog card, default is 0x91");

module_param(verbose, int, 0);
MODULE_PARM_DESC(verbose, "be verbose, default is 0 (no)");

module_param(ticks, int, 0);
MODULE_PARM_DESC(ticks, "count down ticks, default is 10000");
Commit	Line	Data
1da177e4 LT	1	/*
	2	* sma cpu5 watchdog driver
	3	*
	4	* Copyright (C) 2003 Heiko Ronsdorf <hero@ihg.uni-duisburg.de>
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License as published by
	8	* the Free Software Foundation; either version 2 of the License, or
	9	* (at your option) any later version.
	10	*
	11	* This program is distributed in the hope that it will be useful,
	12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	* GNU General Public License for more details.
	15	*
	16	* You should have received a copy of the GNU General Public License
	17	* along with this program; if not, write to the Free Software
	18	* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
	19	*
	20	*/
	21
	22	#include <linux/module.h>
	23	#include <linux/moduleparam.h>
	24	#include <linux/types.h>
	25	#include <linux/errno.h>
	26	#include <linux/miscdevice.h>
	27	#include <linux/fs.h>
	28	#include <linux/init.h>
	29	#include <linux/ioport.h>
	30	#include <linux/timer.h>
3fe0c277	31	#include <linux/completion.h>
4e57b681	32	#include <linux/jiffies.h>
6f932f18 AC	33	#include <linux/io.h>
6f932f18 AC	34	#include <linux/uaccess.h>
1da177e4 LT	35	#include <linux/watchdog.h>
	36
	37	/* adjustable parameters */
	38
6f932f18	39	static int verbose;
1da177e4 LT	40	static int port = 0x91;
1da177e4 LT	41	static int ticks = 10000;
6f932f18	42	static spinlock_t cpu5wdt_lock;
1da177e4 LT	43
	44	#define PFX "cpu5wdt: "
	45
	46	#define CPU5WDT_EXTENT 0x0A
	47
	48	#define CPU5WDT_STATUS_REG 0x00
	49	#define CPU5WDT_TIME_A_REG 0x02
	50	#define CPU5WDT_TIME_B_REG 0x03
	51	#define CPU5WDT_MODE_REG 0x04
	52	#define CPU5WDT_TRIGGER_REG 0x07
	53	#define CPU5WDT_ENABLE_REG 0x08
	54	#define CPU5WDT_RESET_REG 0x09
	55
	56	#define CPU5WDT_INTERVAL (HZ/10+1)
	57
	58	/* some device data */
	59
	60	static struct {
3fe0c277	61	struct completion stop;
996d62d4	62	int running;
1da177e4	63	struct timer_list timer;
996d62d4	64	int queue;
1da177e4 LT	65	int default_ticks;
	66	unsigned long inuse;
	67	} cpu5wdt_device;
	68
	69	/* generic helper functions */
	70
	71	static void cpu5wdt_trigger(unsigned long unused)
	72	{
6f932f18	73	if (verbose > 2)
1da177e4 LT	74	printk(KERN_DEBUG PFX "trigger at %i ticks\n", ticks);
1da177e4 LT	75
6f932f18	76	if (cpu5wdt_device.running)
1da177e4 LT	77	ticks--;
1da177e4 LT	78
6f932f18	79	spin_lock(&cpu5wdt_lock);
1da177e4 LT	80	/* keep watchdog alive */
	81	outb(1, port + CPU5WDT_TRIGGER_REG);
	82
	83	/* requeue?? */
82eb7c50 JS	84	if (cpu5wdt_device.queue && ticks)
82eb7c50 JS	85	mod_timer(&cpu5wdt_device.timer, jiffies + CPU5WDT_INTERVAL);
1da177e4 LT	86	else {
1da177e4 LT	87	/* ticks doesn't matter anyway */
3fe0c277	88	complete(&cpu5wdt_device.stop);
1da177e4	89	}
6f932f18	90	spin_unlock(&cpu5wdt_lock);
1da177e4 LT	91
	92	}
	93
	94	static void cpu5wdt_reset(void)
	95	{
	96	ticks = cpu5wdt_device.default_ticks;
	97
6f932f18	98	if (verbose)
1da177e4 LT	99	printk(KERN_DEBUG PFX "reset (%i ticks)\n", (int) ticks);
	100
	101	}
	102
	103	static void cpu5wdt_start(void)
	104	{
6f932f18 AC	105	unsigned long flags;
	106
	107	spin_lock_irqsave(&cpu5wdt_lock, flags);
	108	if (!cpu5wdt_device.queue) {
1da177e4 LT	109	cpu5wdt_device.queue = 1;
	110	outb(0, port + CPU5WDT_TIME_A_REG);
	111	outb(0, port + CPU5WDT_TIME_B_REG);
	112	outb(1, port + CPU5WDT_MODE_REG);
	113	outb(0, port + CPU5WDT_RESET_REG);
	114	outb(0, port + CPU5WDT_ENABLE_REG);
82eb7c50	115	mod_timer(&cpu5wdt_device.timer, jiffies + CPU5WDT_INTERVAL);
1da177e4 LT	116	}
	117	/* if process dies, counter is not decremented */
	118	cpu5wdt_device.running++;
6f932f18	119	spin_unlock_irqrestore(&cpu5wdt_lock, flags);
1da177e4 LT	120	}
	121
	122	static int cpu5wdt_stop(void)
	123	{
6f932f18	124	unsigned long flags;
1da177e4	125
6f932f18 AC	126	spin_lock_irqsave(&cpu5wdt_lock, flags);
	127	if (cpu5wdt_device.running)
	128	cpu5wdt_device.running = 0;
1da177e4	129	ticks = cpu5wdt_device.default_ticks;
6f932f18 AC	130	spin_unlock_irqrestore(&cpu5wdt_lock, flags);
6f932f18 AC	131	if (verbose)
1da177e4	132	printk(KERN_CRIT PFX "stop not possible\n");
1da177e4 LT	133	return -EIO;
	134	}
	135
	136	/* filesystem operations */
	137
	138	static int cpu5wdt_open(struct inode inode, struct file file)
	139	{
6f932f18	140	if (test_and_set_bit(0, &cpu5wdt_device.inuse))
1da177e4	141	return -EBUSY;
1da177e4 LT	142	return nonseekable_open(inode, file);
	143	}
	144
	145	static int cpu5wdt_release(struct inode inode, struct file file)
	146	{
	147	clear_bit(0, &cpu5wdt_device.inuse);
	148	return 0;
	149	}
	150
6f932f18 AC	151	static long cpu5wdt_ioctl(struct file *file, unsigned int cmd,
6f932f18 AC	152	unsigned long arg)
1da177e4 LT	153	{
1da177e4 LT	154	void __user argp = (void __user )arg;
6f932f18	155	int __user *p = argp;
1da177e4	156	unsigned int value;
42747d71	157	static const struct watchdog_info ident = {
1da177e4 LT	158	.options = WDIOF_CARDRESET,
	159	.identity = "CPU5 WDT",
	160	};
	161
6f932f18	162	switch (cmd) {
0c06090c WVS	163	case WDIOC_GETSUPPORT:
	164	if (copy_to_user(argp, &ident, sizeof(ident)))
	165	return -EFAULT;
6f932f18 AC	166	break;
	167	case WDIOC_GETSTATUS:
	168	value = inb(port + CPU5WDT_STATUS_REG);
	169	value = (value >> 2) & 1;
	170	return put_user(value, p);
	171	case WDIOC_GETBOOTSTATUS:
	172	return put_user(0, p);
6f932f18 AC	173	case WDIOC_SETOPTIONS:
	174	if (get_user(value, p))
	175	return -EFAULT;
	176	if (value & WDIOS_ENABLECARD)
	177	cpu5wdt_start();
	178	if (value & WDIOS_DISABLECARD)
	179	cpu5wdt_stop();
	180	break;
0c06090c WVS	181	case WDIOC_KEEPALIVE:
	182	cpu5wdt_reset();
	183	break;
6f932f18 AC	184	default:
6f932f18 AC	185	return -ENOTTY;
1da177e4 LT	186	}
	187	return 0;
	188	}
	189
6f932f18 AC	190	static ssize_t cpu5wdt_write(struct file file, const char __user buf,
6f932f18 AC	191	size_t count, loff_t *ppos)
1da177e4	192	{
6f932f18	193	if (!count)
1da177e4	194	return -EIO;
1da177e4	195	cpu5wdt_reset();
1da177e4 LT	196	return count;
	197	}
	198
62322d25	199	static const struct file_operations cpu5wdt_fops = {
1da177e4 LT	200	.owner = THIS_MODULE,
1da177e4 LT	201	.llseek = no_llseek,
6f932f18	202	.unlocked_ioctl = cpu5wdt_ioctl,
1da177e4 LT	203	.open = cpu5wdt_open,
	204	.write = cpu5wdt_write,
	205	.release = cpu5wdt_release,
	206	};
	207
	208	static struct miscdevice cpu5wdt_misc = {
	209	.minor = WATCHDOG_MINOR,
	210	.name = "watchdog",
	211	.fops = &cpu5wdt_fops,
	212	};
	213
	214	/* init/exit function */
	215
	216	static int __devinit cpu5wdt_init(void)
	217	{
	218	unsigned int val;
	219	int err;
	220
6f932f18 AC	221	if (verbose)
	222	printk(KERN_DEBUG PFX
	223	"port=0x%x, verbose=%i\n", port, verbose);
1da177e4	224
6f932f18 AC	225	init_completion(&cpu5wdt_device.stop);
	226	spin_lock_init(&cpu5wdt_lock);
	227	cpu5wdt_device.queue = 0;
	228	setup_timer(&cpu5wdt_device.timer, cpu5wdt_trigger, 0);
	229	cpu5wdt_device.default_ticks = ticks;
	230
	231	if (!request_region(port, CPU5WDT_EXTENT, PFX)) {
1da177e4 LT	232	printk(KERN_ERR PFX "request_region failed\n");
	233	err = -EBUSY;
	234	goto no_port;
	235	}
	236
	237	/* watchdog reboot? */
	238	val = inb(port + CPU5WDT_STATUS_REG);
	239	val = (val >> 2) & 1;
6f932f18	240	if (!val)
1da177e4 LT	241	printk(KERN_INFO PFX "sorry, was my fault\n");
1da177e4 LT	242
6f932f18 AC	243	err = misc_register(&cpu5wdt_misc);
	244	if (err < 0) {
	245	printk(KERN_ERR PFX "misc_register failed\n");
	246	goto no_misc;
	247	}
1da177e4	248
1da177e4 LT	249
1da177e4 LT	250	printk(KERN_INFO PFX "init success\n");
1da177e4 LT	251	return 0;
1da177e4 LT	252
1da177e4	253	no_misc:
fb8f7ba0 AD	254	release_region(port, CPU5WDT_EXTENT);
fb8f7ba0 AD	255	no_port:
1da177e4 LT	256	return err;
	257	}
	258
	259	static int __devinit cpu5wdt_init_module(void)
	260	{
	261	return cpu5wdt_init();
	262	}
	263
	264	static void __devexit cpu5wdt_exit(void)
	265	{
6f932f18	266	if (cpu5wdt_device.queue) {
1da177e4	267	cpu5wdt_device.queue = 0;
3fe0c277	268	wait_for_completion(&cpu5wdt_device.stop);
1da177e4 LT	269	}
	270
	271	misc_deregister(&cpu5wdt_misc);
	272
	273	release_region(port, CPU5WDT_EXTENT);
	274
	275	}
	276
	277	static void __devexit cpu5wdt_exit_module(void)
	278	{
	279	cpu5wdt_exit();
	280	}
	281
	282	/* module entry points */
	283
	284	module_init(cpu5wdt_init_module);
	285	module_exit(cpu5wdt_exit_module);
	286
	287	MODULE_AUTHOR("Heiko Ronsdorf <hero@ihg.uni-duisburg.de>");
	288	MODULE_DESCRIPTION("sma cpu5 watchdog driver");
	289	MODULE_SUPPORTED_DEVICE("sma cpu5 watchdog");
	290	MODULE_LICENSE("GPL");
	291	MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
	292
	293	module_param(port, int, 0);
	294	MODULE_PARM_DESC(port, "base address of watchdog card, default is 0x91");
	295
	296	module_param(verbose, int, 0);
	297	MODULE_PARM_DESC(verbose, "be verbose, default is 0 (no)");
	298
	299	module_param(ticks, int, 0);
	300	MODULE_PARM_DESC(ticks, "count down ticks, default is 10000");