[mirror_ubuntu-zesty-kernel.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 <asm/io.h>
#include <asm/uaccess.h>

#include <linux/watchdog.h>

/* adjustable parameters */

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

#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--;

	/* 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);
	}

}

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)
{
	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++;
}

static int cpu5wdt_stop(void)
{
	if ( cpu5wdt_device.running )
		cpu5wdt_device.running = 0;

	ticks = cpu5wdt_device.default_ticks;

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

	switch(cmd) {
		case WDIOC_KEEPALIVE:
			cpu5wdt_reset();
			break;
		case WDIOC_GETSTATUS:
			value = inb(port + CPU5WDT_STATUS_REG);
			value = (value >> 2) & 1;
			if ( copy_to_user(argp, &value, sizeof(int)) )
				return -EFAULT;
			break;
		case WDIOC_GETBOOTSTATUS:
			if ( copy_to_user(argp, &value, sizeof(int)) )
				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:
					cpu5wdt_start();
					break;
				case WDIOS_DISABLECARD:
					return cpu5wdt_stop();
				default:
					return -EINVAL;
			}
			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,
	.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);

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

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

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

	init_completion(&cpu5wdt_device.stop);
	cpu5wdt_device.queue = 0;

	clear_bit(0, &cpu5wdt_device.inuse);

	setup_timer(&cpu5wdt_device.timer, cpu5wdt_trigger, 0);

	cpu5wdt_device.default_ticks = ticks;

	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>
1da177e4 LT	33	#include <asm/io.h>
	34	#include <asm/uaccess.h>
	35
	36	#include <linux/watchdog.h>
	37
	38	/* adjustable parameters */
	39
	40	static int verbose = 0;
	41	static int port = 0x91;
	42	static int ticks = 10000;
	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	{
	73	if ( verbose > 2 )
	74	printk(KERN_DEBUG PFX "trigger at %i ticks\n", ticks);
	75
	76	if( cpu5wdt_device.running )
	77	ticks--;
	78
	79	/* keep watchdog alive */
	80	outb(1, port + CPU5WDT_TRIGGER_REG);
	81
	82	/* requeue?? */
82eb7c50 JS	83	if (cpu5wdt_device.queue && ticks)
82eb7c50 JS	84	mod_timer(&cpu5wdt_device.timer, jiffies + CPU5WDT_INTERVAL);
1da177e4 LT	85	else {
1da177e4 LT	86	/* ticks doesn't matter anyway */
3fe0c277	87	complete(&cpu5wdt_device.stop);
1da177e4 LT	88	}
	89
	90	}
	91
	92	static void cpu5wdt_reset(void)
	93	{
	94	ticks = cpu5wdt_device.default_ticks;
	95
	96	if ( verbose )
	97	printk(KERN_DEBUG PFX "reset (%i ticks)\n", (int) ticks);
	98
	99	}
	100
	101	static void cpu5wdt_start(void)
	102	{
	103	if ( !cpu5wdt_device.queue ) {
	104	cpu5wdt_device.queue = 1;
	105	outb(0, port + CPU5WDT_TIME_A_REG);
	106	outb(0, port + CPU5WDT_TIME_B_REG);
	107	outb(1, port + CPU5WDT_MODE_REG);
	108	outb(0, port + CPU5WDT_RESET_REG);
	109	outb(0, port + CPU5WDT_ENABLE_REG);
82eb7c50	110	mod_timer(&cpu5wdt_device.timer, jiffies + CPU5WDT_INTERVAL);
1da177e4 LT	111	}
	112	/* if process dies, counter is not decremented */
	113	cpu5wdt_device.running++;
	114	}
	115
	116	static int cpu5wdt_stop(void)
	117	{
	118	if ( cpu5wdt_device.running )
	119	cpu5wdt_device.running = 0;
	120
	121	ticks = cpu5wdt_device.default_ticks;
	122
	123	if ( verbose )
	124	printk(KERN_CRIT PFX "stop not possible\n");
	125
	126	return -EIO;
	127	}
	128
	129	/* filesystem operations */
	130
	131	static int cpu5wdt_open(struct inode inode, struct file file)
	132	{
	133	if ( test_and_set_bit(0, &cpu5wdt_device.inuse) )
	134	return -EBUSY;
	135
	136	return nonseekable_open(inode, file);
	137	}
	138
	139	static int cpu5wdt_release(struct inode inode, struct file file)
	140	{
	141	clear_bit(0, &cpu5wdt_device.inuse);
	142	return 0;
	143	}
	144
	145	static int cpu5wdt_ioctl(struct inode inode, struct file file, unsigned int cmd, unsigned long arg)
	146	{
	147	void __user argp = (void __user )arg;
	148	unsigned int value;
	149	static struct watchdog_info ident =
	150	{
	151	.options = WDIOF_CARDRESET,
	152	.identity = "CPU5 WDT",
	153	};
	154
	155	switch(cmd) {
	156	case WDIOC_KEEPALIVE:
	157	cpu5wdt_reset();
	158	break;
	159	case WDIOC_GETSTATUS:
	160	value = inb(port + CPU5WDT_STATUS_REG);
	161	value = (value >> 2) & 1;
	162	if ( copy_to_user(argp, &value, sizeof(int)) )
	163	return -EFAULT;
	164	break;
5c4eb61b WVS	165	case WDIOC_GETBOOTSTATUS:
5c4eb61b WVS	166	if ( copy_to_user(argp, &value, sizeof(int)) )
4e24f4ed	167	return -EFAULT;
5c4eb61b	168	break;
1da177e4 LT	169	case WDIOC_GETSUPPORT:
	170	if ( copy_to_user(argp, &ident, sizeof(ident)) )
	171	return -EFAULT;
	172	break;
	173	case WDIOC_SETOPTIONS:
	174	if ( copy_from_user(&value, argp, sizeof(int)) )
	175	return -EFAULT;
	176	switch(value) {
	177	case WDIOS_ENABLECARD:
	178	cpu5wdt_start();
	179	break;
	180	case WDIOS_DISABLECARD:
	181	return cpu5wdt_stop();
	182	default:
	183	return -EINVAL;
	184	}
	185	break;
	186	default:
795b89d2	187	return -ENOTTY;
1da177e4 LT	188	}
	189	return 0;
	190	}
	191
	192	static ssize_t cpu5wdt_write(struct file file, const char __user buf, size_t count, loff_t *ppos)
	193	{
	194	if ( !count )
	195	return -EIO;
	196
	197	cpu5wdt_reset();
	198
	199	return count;
	200	}
	201
62322d25	202	static const struct file_operations cpu5wdt_fops = {
1da177e4 LT	203	.owner = THIS_MODULE,
	204	.llseek = no_llseek,
	205	.ioctl = cpu5wdt_ioctl,
	206	.open = cpu5wdt_open,
	207	.write = cpu5wdt_write,
	208	.release = cpu5wdt_release,
	209	};
	210
	211	static struct miscdevice cpu5wdt_misc = {
	212	.minor = WATCHDOG_MINOR,
	213	.name = "watchdog",
	214	.fops = &cpu5wdt_fops,
	215	};
	216
	217	/* init/exit function */
	218
	219	static int __devinit cpu5wdt_init(void)
	220	{
	221	unsigned int val;
	222	int err;
	223
	224	if ( verbose )
	225	printk(KERN_DEBUG PFX "port=0x%x, verbose=%i\n", port, verbose);
	226
1da177e4 LT	227	if ( !request_region(port, CPU5WDT_EXTENT, PFX) ) {
	228	printk(KERN_ERR PFX "request_region failed\n");
	229	err = -EBUSY;
	230	goto no_port;
	231	}
	232
fb8f7ba0 AD	233	if ( (err = misc_register(&cpu5wdt_misc)) < 0 ) {
	234	printk(KERN_ERR PFX "misc_register failed\n");
	235	goto no_misc;
	236	}
	237
1da177e4 LT	238	/* watchdog reboot? */
	239	val = inb(port + CPU5WDT_STATUS_REG);
	240	val = (val >> 2) & 1;
	241	if ( !val )
	242	printk(KERN_INFO PFX "sorry, was my fault\n");
	243
3fe0c277	244	init_completion(&cpu5wdt_device.stop);
1da177e4 LT	245	cpu5wdt_device.queue = 0;
	246
	247	clear_bit(0, &cpu5wdt_device.inuse);
	248
82eb7c50	249	setup_timer(&cpu5wdt_device.timer, cpu5wdt_trigger, 0);
1da177e4 LT	250
	251	cpu5wdt_device.default_ticks = ticks;
	252
	253	printk(KERN_INFO PFX "init success\n");
	254
	255	return 0;
	256
1da177e4	257	no_misc:
fb8f7ba0 AD	258	release_region(port, CPU5WDT_EXTENT);
fb8f7ba0 AD	259	no_port:
1da177e4 LT	260	return err;
	261	}
	262
	263	static int __devinit cpu5wdt_init_module(void)
	264	{
	265	return cpu5wdt_init();
	266	}
	267
	268	static void __devexit cpu5wdt_exit(void)
	269	{
	270	if ( cpu5wdt_device.queue ) {
	271	cpu5wdt_device.queue = 0;
3fe0c277	272	wait_for_completion(&cpu5wdt_device.stop);
1da177e4 LT	273	}
	274
	275	misc_deregister(&cpu5wdt_misc);
	276
	277	release_region(port, CPU5WDT_EXTENT);
	278
	279	}
	280
	281	static void __devexit cpu5wdt_exit_module(void)
	282	{
	283	cpu5wdt_exit();
	284	}
	285
	286	/* module entry points */
	287
	288	module_init(cpu5wdt_init_module);
	289	module_exit(cpu5wdt_exit_module);
	290
	291	MODULE_AUTHOR("Heiko Ronsdorf <hero@ihg.uni-duisburg.de>");
	292	MODULE_DESCRIPTION("sma cpu5 watchdog driver");
	293	MODULE_SUPPORTED_DEVICE("sma cpu5 watchdog");
	294	MODULE_LICENSE("GPL");
	295	MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
	296
	297	module_param(port, int, 0);
	298	MODULE_PARM_DESC(port, "base address of watchdog card, default is 0x91");
	299
	300	module_param(verbose, int, 0);
	301	MODULE_PARM_DESC(verbose, "be verbose, default is 0 (no)");
	302
	303	module_param(ticks, int, 0);
	304	MODULE_PARM_DESC(ticks, "count down ticks, default is 10000");