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

/*
 * MixCom Watchdog: A Simple Hardware Watchdog Device
 * Based on Softdog driver by Alan Cox and PC Watchdog driver by Ken Hollis
 *
 * Author: Gergely Madarasz <gorgo@itc.hu>
 *
 * Copyright (c) 1999 ITConsult-Pro Co. <info@itc.hu>
 *
 * 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.
 *
 * Version 0.1 (99/04/15):
 *		- first version
 *
 * Version 0.2 (99/06/16):
 *		- added kernel timer watchdog ping after close
 *		  since the hardware does not support watchdog shutdown
 *
 * Version 0.3 (99/06/21):
 *		- added WDIOC_GETSTATUS and WDIOC_GETSUPPORT ioctl calls
 *
 * Version 0.3.1 (99/06/22):
 *		- allow module removal while internal timer is active,
 *		  print warning about probable reset
 *
 * Version 0.4 (99/11/15):
 *		- support for one more type board
 *
 * Version 0.5 (2001/12/14) Matt Domsch <Matt_Domsch@dell.com>
 *		- added nowayout module option to override
 *		  CONFIG_WATCHDOG_NOWAYOUT
 *
 * Version 0.6 (2002/04/12): Rob Radez <rob@osinvestor.com>
 *		- make mixcomwd_opened unsigned,
 *		  removed lock_kernel/unlock_kernel from mixcomwd_release,
 *		  modified ioctl a bit to conform to API
 *
 */

#define VERSION "0.6"
#define WATCHDOG_NAME "mixcomwd"
#define PFX WATCHDOG_NAME ": "

#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/types.h>
#include <linux/miscdevice.h>
#include <linux/ioport.h>
#include <linux/watchdog.h>
#include <linux/fs.h>
#include <linux/reboot.h>
#include <linux/init.h>
#include <linux/jiffies.h>
#include <linux/timer.h>
#include <linux/uaccess.h>
#include <linux/io.h>

/*
 * We have two types of cards that can be probed:
 * 1) The Mixcom cards: these cards can be found at addresses
 *    0x180, 0x280, 0x380 with an additional offset of 0xc10.
 *    (Or 0xd90, 0xe90, 0xf90).
 * 2) The FlashCOM cards: these cards can be set up at
 *    0x300 -> 0x378, in 0x8 jumps with an offset of 0x04.
 *    (Or 0x304 -> 0x37c in 0x8 jumps).
 *    Each card has it's own ID.
 */
#define MIXCOM_ID 0x11
#define FLASHCOM_ID 0x18
static struct {
	int ioport;
	int id;
} mixcomwd_io_info[] __devinitdata = {
	/* The Mixcom cards */
	{0x0d90, MIXCOM_ID},
	{0x0e90, MIXCOM_ID},
	{0x0f90, MIXCOM_ID},
	/* The FlashCOM cards */
	{0x0304, FLASHCOM_ID},
	{0x030c, FLASHCOM_ID},
	{0x0314, FLASHCOM_ID},
	{0x031c, FLASHCOM_ID},
	{0x0324, FLASHCOM_ID},
	{0x032c, FLASHCOM_ID},
	{0x0334, FLASHCOM_ID},
	{0x033c, FLASHCOM_ID},
	{0x0344, FLASHCOM_ID},
	{0x034c, FLASHCOM_ID},
	{0x0354, FLASHCOM_ID},
	{0x035c, FLASHCOM_ID},
	{0x0364, FLASHCOM_ID},
	{0x036c, FLASHCOM_ID},
	{0x0374, FLASHCOM_ID},
	{0x037c, FLASHCOM_ID},
	/* The end of the list */
	{0x0000, 0},
};

static void mixcomwd_timerfun(unsigned long d);

static unsigned long mixcomwd_opened; /* long req'd for setbit --RR */

static int watchdog_port;
static int mixcomwd_timer_alive;
static DEFINE_TIMER(mixcomwd_timer, mixcomwd_timerfun, 0, 0);
static char expect_close;

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

static void mixcomwd_ping(void)
{
	outb_p(55, watchdog_port);
	return;
}

static void mixcomwd_timerfun(unsigned long d)
{
	mixcomwd_ping();
	mod_timer(&mixcomwd_timer, jiffies + 5 * HZ);
}

/*
 *	Allow only one person to hold it open
 */

static int mixcomwd_open(struct inode *inode, struct file *file)
{
	if (test_and_set_bit(0, &mixcomwd_opened))
		return -EBUSY;

	mixcomwd_ping();

	if (nowayout)
		/*
		 * fops_get() code via open() has already done
		 * a try_module_get() so it is safe to do the
		 * __module_get().
		 */
		__module_get(THIS_MODULE);
	else {
		if (mixcomwd_timer_alive) {
			del_timer(&mixcomwd_timer);
			mixcomwd_timer_alive = 0;
		}
	}
	return nonseekable_open(inode, file);
}

static int mixcomwd_release(struct inode *inode, struct file *file)
{
	if (expect_close == 42) {
		if (mixcomwd_timer_alive) {
			printk(KERN_ERR PFX
				"release called while internal timer alive");
			return -EBUSY;
		}
		mixcomwd_timer_alive = 1;
		mod_timer(&mixcomwd_timer, jiffies + 5 * HZ);
	} else
		printk(KERN_CRIT PFX
		    "WDT device closed unexpectedly.  WDT will not stop!\n");

	clear_bit(0, &mixcomwd_opened);
	expect_close = 0;
	return 0;
}


static ssize_t mixcomwd_write(struct file *file, const char __user *data,
						size_t len, loff_t *ppos)
{
	if (len) {
		if (!nowayout) {
			size_t i;

			/* In case it was set long ago */
			expect_close = 0;

			for (i = 0; i != len; i++) {
				char c;
				if (get_user(c, data + i))
					return -EFAULT;
				if (c == 'V')
					expect_close = 42;
			}
		}
		mixcomwd_ping();
	}
	return len;
}

static long mixcomwd_ioctl(struct file *file,
				unsigned int cmd, unsigned long arg)
{
	void __user *argp = (void __user *)arg;
	int __user *p = argp;
	int status;
	static const struct watchdog_info ident = {
		.options = WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
		.firmware_version = 1,
		.identity = "MixCOM watchdog",
	};

	switch (cmd) {
	case WDIOC_GETSUPPORT:
		if (copy_to_user(argp, &ident, sizeof(ident)))
			return -EFAULT;
		break;
	case WDIOC_GETSTATUS:
		status = mixcomwd_opened;
		if (!nowayout)
			status |= mixcomwd_timer_alive;
		return put_user(status, p);
	case WDIOC_GETBOOTSTATUS:
		return put_user(0, p);
	case WDIOC_KEEPALIVE:
		mixcomwd_ping();
		break;
	default:
		return -ENOTTY;
	}
	return 0;
}

static const struct file_operations mixcomwd_fops = {
	.owner		= THIS_MODULE,
	.llseek		= no_llseek,
	.write		= mixcomwd_write,
	.unlocked_ioctl	= mixcomwd_ioctl,
	.open		= mixcomwd_open,
	.release	= mixcomwd_release,
};

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

static int __init checkcard(int port, int card_id)
{
	int id;

	if (!request_region(port, 1, "MixCOM watchdog"))
		return 0;

	id = inb_p(port);
	if (card_id == MIXCOM_ID)
		id &= 0x3f;

	if (id != card_id) {
		release_region(port, 1);
		return 0;
	}
	return 1;
}

static int __init mixcomwd_init(void)
{
	int i, ret, found = 0;

	for (i = 0; !found && mixcomwd_io_info[i].ioport != 0; i++) {
		if (checkcard(mixcomwd_io_info[i].ioport,
			      mixcomwd_io_info[i].id)) {
			found = 1;
			watchdog_port = mixcomwd_io_info[i].ioport;
		}
	}

	if (!found) {
		printk(KERN_ERR PFX
			"No card detected, or port not available.\n");
		return -ENODEV;
	}

	ret = misc_register(&mixcomwd_miscdev);
	if (ret) {
		printk(KERN_ERR PFX
			"cannot register miscdev on minor=%d (err=%d)\n",
					WATCHDOG_MINOR, ret);
		goto error_misc_register_watchdog;
	}

	printk(KERN_INFO
		"MixCOM watchdog driver v%s, watchdog port at 0x%3x\n",
					VERSION, watchdog_port);

	return 0;

error_misc_register_watchdog:
	release_region(watchdog_port, 1);
	watchdog_port = 0x0000;
	return ret;
}

static void __exit mixcomwd_exit(void)
{
	if (!nowayout) {
		if (mixcomwd_timer_alive) {
			printk(KERN_WARNING PFX "I quit now, hardware will"
			       " probably reboot!\n");
			del_timer_sync(&mixcomwd_timer);
			mixcomwd_timer_alive = 0;
		}
	}
	misc_deregister(&mixcomwd_miscdev);
	release_region(watchdog_port, 1);
}

module_init(mixcomwd_init);
module_exit(mixcomwd_exit);

MODULE_AUTHOR("Gergely Madarasz <gorgo@itc.hu>");
MODULE_DESCRIPTION("MixCom Watchdog driver");
MODULE_VERSION(VERSION);
MODULE_LICENSE("GPL");
MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
Commit	Line	Data
1da177e4 LT	1	/*
	2	* MixCom Watchdog: A Simple Hardware Watchdog Device
	3	* Based on Softdog driver by Alan Cox and PC Watchdog driver by Ken Hollis
	4	*
	5	* Author: Gergely Madarasz <gorgo@itc.hu>
	6	*
	7	* Copyright (c) 1999 ITConsult-Pro Co. <info@itc.hu>
	8	*
	9	* This program is free software; you can redistribute it and/or
	10	* modify it under the terms of the GNU General Public License
	11	* as published by the Free Software Foundation; either version
	12	* 2 of the License, or (at your option) any later version.
	13	*
	14	* Version 0.1 (99/04/15):
	15	* - first version
	16	*
	17	* Version 0.2 (99/06/16):
	18	* - added kernel timer watchdog ping after close
	19	* since the hardware does not support watchdog shutdown
	20	*
	21	* Version 0.3 (99/06/21):
	22	* - added WDIOC_GETSTATUS and WDIOC_GETSUPPORT ioctl calls
	23	*
	24	* Version 0.3.1 (99/06/22):
	25	* - allow module removal while internal timer is active,
	26	* print warning about probable reset
	27	*
	28	* Version 0.4 (99/11/15):
	29	* - support for one more type board
	30	*
	31	* Version 0.5 (2001/12/14) Matt Domsch <Matt_Domsch@dell.com>
39309645 AC	32	* - added nowayout module option to override
39309645 AC	33	* CONFIG_WATCHDOG_NOWAYOUT
b10958d3 WVS	34	*
	35	* Version 0.6 (2002/04/12): Rob Radez <rob@osinvestor.com>
	36	* - make mixcomwd_opened unsigned,
	37	* removed lock_kernel/unlock_kernel from mixcomwd_release,
	38	* modified ioctl a bit to conform to API
1da177e4 LT	39	*
	40	*/
	41
b10958d3	42	#define VERSION "0.6"
1c067318 WVS	43	#define WATCHDOG_NAME "mixcomwd"
1c067318 WVS	44	#define PFX WATCHDOG_NAME ": "
1da177e4 LT	45
	46	#include <linux/module.h>
	47	#include <linux/moduleparam.h>
1da177e4 LT	48	#include <linux/types.h>
	49	#include <linux/miscdevice.h>
	50	#include <linux/ioport.h>
	51	#include <linux/watchdog.h>
	52	#include <linux/fs.h>
	53	#include <linux/reboot.h>
	54	#include <linux/init.h>
4e57b681 TS	55	#include <linux/jiffies.h>
4e57b681 TS	56	#include <linux/timer.h>
39309645 AC	57	#include <linux/uaccess.h>
39309645 AC	58	#include <linux/io.h>
1da177e4	59
63e6e17e WVS	60	/*
	61	* We have two types of cards that can be probed:
	62	* 1) The Mixcom cards: these cards can be found at addresses
	63	* 0x180, 0x280, 0x380 with an additional offset of 0xc10.
	64	* (Or 0xd90, 0xe90, 0xf90).
	65	* 2) The FlashCOM cards: these cards can be set up at
	66	* 0x300 -> 0x378, in 0x8 jumps with an offset of 0x04.
	67	* (Or 0x304 -> 0x37c in 0x8 jumps).
	68	* Each card has it's own ID.
	69	*/
1da177e4	70	#define MIXCOM_ID 0x11
1da177e4	71	#define FLASHCOM_ID 0x18
21baf3c7 WVS	72	static struct {
	73	int ioport;
	74	int id;
	75	} mixcomwd_io_info[] __devinitdata = {
	76	/* The Mixcom cards */
	77	{0x0d90, MIXCOM_ID},
	78	{0x0e90, MIXCOM_ID},
	79	{0x0f90, MIXCOM_ID},
	80	/* The FlashCOM cards */
	81	{0x0304, FLASHCOM_ID},
	82	{0x030c, FLASHCOM_ID},
	83	{0x0314, FLASHCOM_ID},
	84	{0x031c, FLASHCOM_ID},
	85	{0x0324, FLASHCOM_ID},
	86	{0x032c, FLASHCOM_ID},
	87	{0x0334, FLASHCOM_ID},
	88	{0x033c, FLASHCOM_ID},
	89	{0x0344, FLASHCOM_ID},
	90	{0x034c, FLASHCOM_ID},
	91	{0x0354, FLASHCOM_ID},
	92	{0x035c, FLASHCOM_ID},
	93	{0x0364, FLASHCOM_ID},
	94	{0x036c, FLASHCOM_ID},
	95	{0x0374, FLASHCOM_ID},
	96	{0x037c, FLASHCOM_ID},
	97	/* The end of the list */
	98	{0x0000, 0},
	99	};
1da177e4	100
82eb7c50 JS	101	static void mixcomwd_timerfun(unsigned long d);
82eb7c50 JS	102
1da177e4 LT	103	static unsigned long mixcomwd_opened; /* long req'd for setbit --RR */
	104
	105	static int watchdog_port;
	106	static int mixcomwd_timer_alive;
82eb7c50	107	static DEFINE_TIMER(mixcomwd_timer, mixcomwd_timerfun, 0, 0);
1da177e4 LT	108	static char expect_close;
1da177e4 LT	109
4bfdf378	110	static int nowayout = WATCHDOG_NOWAYOUT;
1da177e4	111	module_param(nowayout, int, 0);
39309645 AC	112	MODULE_PARM_DESC(nowayout,
	113	"Watchdog cannot be stopped once started (default="
	114	__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
1da177e4 LT	115
	116	static void mixcomwd_ping(void)
	117	{
39309645	118	outb_p(55, watchdog_port);
1da177e4 LT	119	return;
	120	}
	121
	122	static void mixcomwd_timerfun(unsigned long d)
	123	{
	124	mixcomwd_ping();
82eb7c50	125	mod_timer(&mixcomwd_timer, jiffies + 5 * HZ);
1da177e4 LT	126	}
	127
	128	/*
	129	* Allow only one person to hold it open
	130	*/
	131
	132	static int mixcomwd_open(struct inode inode, struct file file)
	133	{
39309645	134	if (test_and_set_bit(0, &mixcomwd_opened))
1da177e4	135	return -EBUSY;
39309645	136
1da177e4 LT	137	mixcomwd_ping();
1da177e4 LT	138
39309645	139	if (nowayout)
1da177e4 LT	140	/*
	141	* fops_get() code via open() has already done
	142	* a try_module_get() so it is safe to do the
	143	* __module_get().
	144	*/
	145	__module_get(THIS_MODULE);
39309645 AC	146	else {
39309645 AC	147	if (mixcomwd_timer_alive) {
1da177e4	148	del_timer(&mixcomwd_timer);
39309645	149	mixcomwd_timer_alive = 0;
1da177e4 LT	150	}
	151	}
	152	return nonseekable_open(inode, file);
	153	}
	154
	155	static int mixcomwd_release(struct inode inode, struct file file)
	156	{
	157	if (expect_close == 42) {
39309645 AC	158	if (mixcomwd_timer_alive) {
	159	printk(KERN_ERR PFX
	160	"release called while internal timer alive");
1da177e4 LT	161	return -EBUSY;
1da177e4 LT	162	}
39309645	163	mixcomwd_timer_alive = 1;
82eb7c50	164	mod_timer(&mixcomwd_timer, jiffies + 5 * HZ);
39309645 AC	165	} else
	166	printk(KERN_CRIT PFX
	167	"WDT device closed unexpectedly. WDT will not stop!\n");
1da177e4	168
39309645 AC	169	clear_bit(0, &mixcomwd_opened);
39309645 AC	170	expect_close = 0;
1da177e4 LT	171	return 0;
	172	}
	173
	174
39309645 AC	175	static ssize_t mixcomwd_write(struct file file, const char __user data,
39309645 AC	176	size_t len, loff_t *ppos)
1da177e4	177	{
39309645	178	if (len) {
1da177e4 LT	179	if (!nowayout) {
	180	size_t i;
	181
	182	/* In case it was set long ago */
	183	expect_close = 0;
	184
	185	for (i = 0; i != len; i++) {
	186	char c;
	187	if (get_user(c, data + i))
	188	return -EFAULT;
	189	if (c == 'V')
	190	expect_close = 42;
	191	}
	192	}
	193	mixcomwd_ping();
	194	}
	195	return len;
	196	}
	197
39309645 AC	198	static long mixcomwd_ioctl(struct file *file,
39309645 AC	199	unsigned int cmd, unsigned long arg)
1da177e4 LT	200	{
	201	void __user argp = (void __user )arg;
	202	int __user *p = argp;
	203	int status;
42747d71	204	static const struct watchdog_info ident = {
1da177e4 LT	205	.options = WDIOF_KEEPALIVEPING \| WDIOF_MAGICCLOSE,
	206	.firmware_version = 1,
	207	.identity = "MixCOM watchdog",
	208	};
	209
39309645	210	switch (cmd) {
0c06090c WVS	211	case WDIOC_GETSUPPORT:
	212	if (copy_to_user(argp, &ident, sizeof(ident)))
	213	return -EFAULT;
	214	break;
39309645 AC	215	case WDIOC_GETSTATUS:
	216	status = mixcomwd_opened;
	217	if (!nowayout)
	218	status \|= mixcomwd_timer_alive;
	219	return put_user(status, p);
	220	case WDIOC_GETBOOTSTATUS:
	221	return put_user(0, p);
39309645 AC	222	case WDIOC_KEEPALIVE:
	223	mixcomwd_ping();
	224	break;
	225	default:
	226	return -ENOTTY;
1da177e4 LT	227	}
	228	return 0;
	229	}
	230
10a29304	231	static const struct file_operations mixcomwd_fops = {
1da177e4 LT	232	.owner = THIS_MODULE,
	233	.llseek = no_llseek,
	234	.write = mixcomwd_write,
39309645	235	.unlocked_ioctl = mixcomwd_ioctl,
1da177e4 LT	236	.open = mixcomwd_open,
	237	.release = mixcomwd_release,
	238	};
	239
10a29304	240	static struct miscdevice mixcomwd_miscdev = {
1da177e4 LT	241	.minor = WATCHDOG_MINOR,
	242	.name = "watchdog",
	243	.fops = &mixcomwd_fops,
	244	};
	245
4194db10	246	static int __init checkcard(int port, int card_id)
1da177e4 LT	247	{
	248	int id;
	249
39309645	250	if (!request_region(port, 1, "MixCOM watchdog"))
1da177e4	251	return 0;
1da177e4	252
39309645 AC	253	id = inb_p(port);
39309645 AC	254	if (card_id == MIXCOM_ID)
4194db10 WVS	255	id &= 0x3f;
4194db10 WVS	256
39309645	257	if (id != card_id) {
1da177e4 LT	258	release_region(port, 1);
	259	return 0;
	260	}
4194db10 WVS	261	return 1;
4194db10 WVS	262	}
1da177e4 LT	263
	264	static int __init mixcomwd_init(void)
	265	{
39309645	266	int i, ret, found = 0;
1da177e4	267
21baf3c7 WVS	268	for (i = 0; !found && mixcomwd_io_info[i].ioport != 0; i++) {
	269	if (checkcard(mixcomwd_io_info[i].ioport,
	270	mixcomwd_io_info[i].id)) {
1da177e4	271	found = 1;
21baf3c7	272	watchdog_port = mixcomwd_io_info[i].ioport;
1da177e4 LT	273	}
	274	}
	275
	276	if (!found) {
39309645 AC	277	printk(KERN_ERR PFX
39309645 AC	278	"No card detected, or port not available.\n");
1da177e4 LT	279	return -ENODEV;
	280	}
	281
	282	ret = misc_register(&mixcomwd_miscdev);
39309645 AC	283	if (ret) {
	284	printk(KERN_ERR PFX
	285	"cannot register miscdev on minor=%d (err=%d)\n",
	286	WATCHDOG_MINOR, ret);
27c7742e	287	goto error_misc_register_watchdog;
1da177e4 LT	288	}
1da177e4 LT	289
39309645 AC	290	printk(KERN_INFO
	291	"MixCOM watchdog driver v%s, watchdog port at 0x%3x\n",
	292	VERSION, watchdog_port);
1da177e4 LT	293
1da177e4 LT	294	return 0;
27c7742e WVS	295
	296	error_misc_register_watchdog:
	297	release_region(watchdog_port, 1);
	298	watchdog_port = 0x0000;
	299	return ret;
1da177e4 LT	300	}
	301
	302	static void __exit mixcomwd_exit(void)
	303	{
	304	if (!nowayout) {
39309645	305	if (mixcomwd_timer_alive) {
1c067318	306	printk(KERN_WARNING PFX "I quit now, hardware will"
1da177e4	307	" probably reboot!\n");
82eb7c50	308	del_timer_sync(&mixcomwd_timer);
39309645	309	mixcomwd_timer_alive = 0;
1da177e4 LT	310	}
1da177e4 LT	311	}
1da177e4	312	misc_deregister(&mixcomwd_miscdev);
39309645	313	release_region(watchdog_port, 1);
1da177e4 LT	314	}
	315
	316	module_init(mixcomwd_init);
	317	module_exit(mixcomwd_exit);
	318
	319	MODULE_AUTHOR("Gergely Madarasz <gorgo@itc.hu>");
	320	MODULE_DESCRIPTION("MixCom Watchdog driver");
1c067318	321	MODULE_VERSION(VERSION);
1da177e4 LT	322	MODULE_LICENSE("GPL");
1da177e4 LT	323	MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);