[linux-2.6] / drivers / watchdog / rm9k_wdt.c

/*
 *  Watchdog implementation for GPI h/w found on PMC-Sierra RM9xxx
 *  chips.
 *
 *  Copyright (C) 2004 by Basler Vision Technologies AG
 *  Author: Thomas Koeller <thomas.koeller@baslerweb.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 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#include <linux/platform_device.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/interrupt.h>
#include <linux/fs.h>
#include <linux/reboot.h>
#include <linux/notifier.h>
#include <linux/miscdevice.h>
#include <linux/watchdog.h>
#include <asm/io.h>
#include <asm/atomic.h>
#include <asm/processor.h>
#include <asm/uaccess.h>
#include <asm/system.h>
#include <asm/rm9k-ocd.h>

#include <rm9k_wdt.h>


#define CLOCK                  125000000
#define MAX_TIMEOUT_SECONDS    32
#define CPCCR                  0x0080
#define CPGIG1SR               0x0044
#define CPGIG1ER               0x0054


/* Function prototypes */
static irqreturn_t wdt_gpi_irqhdl(int, void *);
static void wdt_gpi_start(void);
static void wdt_gpi_stop(void);
static void wdt_gpi_set_timeout(unsigned int);
static int wdt_gpi_open(struct inode *, struct file *);
static int wdt_gpi_release(struct inode *, struct file *);
static ssize_t wdt_gpi_write(struct file *, const char __user *, size_t, loff_t *);
static long wdt_gpi_ioctl(struct file *, unsigned int, unsigned long);
static int wdt_gpi_notify(struct notifier_block *, unsigned long, void *);
static const struct resource *wdt_gpi_get_resource(struct platform_device *, const char *, unsigned int);
static int __init wdt_gpi_probe(struct device *);
static int __exit wdt_gpi_remove(struct device *);


static const char wdt_gpi_name[] = "wdt_gpi";
static atomic_t opencnt;
static int expect_close;
static int locked;


/* These are set from device resources */
static void __iomem * wd_regs;
static unsigned int wd_irq, wd_ctr;


/* Module arguments */
static int timeout = MAX_TIMEOUT_SECONDS;
module_param(timeout, int, 0444);
MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds");

static unsigned long resetaddr = 0xbffdc200;
module_param(resetaddr, ulong, 0444);
MODULE_PARM_DESC(resetaddr, "Address to write to to force a reset");

static unsigned long flagaddr = 0xbffdc104;
module_param(flagaddr, ulong, 0444);
MODULE_PARM_DESC(flagaddr, "Address to write to boot flags to");

static int powercycle;
module_param(powercycle, bool, 0444);
MODULE_PARM_DESC(powercycle, "Cycle power if watchdog expires");

static int nowayout = WATCHDOG_NOWAYOUT;
module_param(nowayout, bool, 0444);
MODULE_PARM_DESC(nowayout, "Watchdog cannot be disabled once started");


/* Kernel interfaces */
static const struct file_operations fops = {
	.owner		= THIS_MODULE,
	.open		= wdt_gpi_open,
	.release	= wdt_gpi_release,
	.write		= wdt_gpi_write,
	.unlocked_ioctl	= wdt_gpi_ioctl,
};

static struct miscdevice miscdev = {
	.minor		= WATCHDOG_MINOR,
	.name		= wdt_gpi_name,
	.fops		= &fops,
};

static struct notifier_block wdt_gpi_shutdown = {
	.notifier_call	= wdt_gpi_notify,
};


/* Interrupt handler */
static irqreturn_t wdt_gpi_irqhdl(int irq, void *ctxt)
{
	if (!unlikely(__raw_readl(wd_regs + 0x0008) & 0x1))
		return IRQ_NONE;
	__raw_writel(0x1, wd_regs + 0x0008);


	printk(KERN_CRIT "%s: watchdog expired - resetting system\n",
		wdt_gpi_name);

	*(volatile char *) flagaddr |= 0x01;
	*(volatile char *) resetaddr = powercycle ? 0x01 : 0x2;
	iob();
	while (1)
		cpu_relax();
}


/* Watchdog functions */
static void wdt_gpi_start(void)
{
	u32 reg;

	lock_titan_regs();
	reg = titan_readl(CPGIG1ER);
	titan_writel(reg | (0x100 << wd_ctr), CPGIG1ER);
	iob();
	unlock_titan_regs();
}

static void wdt_gpi_stop(void)
{
	u32 reg;

	lock_titan_regs();
	reg = titan_readl(CPCCR) & ~(0xf << (wd_ctr * 4));
	titan_writel(reg, CPCCR);
	reg = titan_readl(CPGIG1ER);
	titan_writel(reg & ~(0x100 << wd_ctr), CPGIG1ER);
	iob();
	unlock_titan_regs();
}

static void wdt_gpi_set_timeout(unsigned int to)
{
	u32 reg;
	const u32 wdval = (to * CLOCK) & ~0x0000000f;

	lock_titan_regs();
	reg = titan_readl(CPCCR) & ~(0xf << (wd_ctr * 4));
	titan_writel(reg, CPCCR);
	wmb();
	__raw_writel(wdval, wd_regs + 0x0000);
	wmb();
	titan_writel(reg | (0x2 << (wd_ctr * 4)), CPCCR);
	wmb();
	titan_writel(reg | (0x5 << (wd_ctr * 4)), CPCCR);
	iob();
	unlock_titan_regs();
}


/* /dev/watchdog operations */
static int wdt_gpi_open(struct inode *inode, struct file *file)
{
	int res;

	if (unlikely(atomic_dec_if_positive(&opencnt) < 0))
		return -EBUSY;

	expect_close = 0;
	if (locked) {
		module_put(THIS_MODULE);
		free_irq(wd_irq, &miscdev);
		locked = 0;
	}

	res = request_irq(wd_irq, wdt_gpi_irqhdl, IRQF_SHARED | IRQF_DISABLED,
			  wdt_gpi_name, &miscdev);
	if (unlikely(res))
		return res;

	wdt_gpi_set_timeout(timeout);
	wdt_gpi_start();

	printk(KERN_INFO "%s: watchdog started, timeout = %u seconds\n",
		wdt_gpi_name, timeout);
	return nonseekable_open(inode, file);
}

static int wdt_gpi_release(struct inode *inode, struct file *file)
{
	if (nowayout) {
		printk(KERN_INFO "%s: no way out - watchdog left running\n",
			wdt_gpi_name);
		__module_get(THIS_MODULE);
		locked = 1;
	} else {
		if (expect_close) {
			wdt_gpi_stop();
			free_irq(wd_irq, &miscdev);
			printk(KERN_INFO "%s: watchdog stopped\n", wdt_gpi_name);
		} else {
			printk(KERN_CRIT "%s: unexpected close() -"
				" watchdog left running\n",
				wdt_gpi_name);
			wdt_gpi_set_timeout(timeout);
			__module_get(THIS_MODULE);
			locked = 1;
		}
	}

	atomic_inc(&opencnt);
	return 0;
}

static ssize_t
wdt_gpi_write(struct file *f, const char __user *d, size_t s, loff_t *o)
{
	char val;

	wdt_gpi_set_timeout(timeout);
	expect_close = (s > 0) && !get_user(val, d) && (val == 'V');
	return s ? 1 : 0;
}

static long
wdt_gpi_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
{
	long res = -ENOTTY;
	const long size = _IOC_SIZE(cmd);
	int stat;
	void __user *argp = (void __user *)arg;
	static struct watchdog_info wdinfo = {
		.identity               = "RM9xxx/GPI watchdog",
		.firmware_version       = 0,
		.options                = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING
	};

	if (unlikely(_IOC_TYPE(cmd) != WATCHDOG_IOCTL_BASE))
		return -ENOTTY;

	if ((_IOC_DIR(cmd) & _IOC_READ)
	    && !access_ok(VERIFY_WRITE, arg, size))
		return -EFAULT;

	if ((_IOC_DIR(cmd) & _IOC_WRITE)
	    && !access_ok(VERIFY_READ, arg, size))
		return -EFAULT;

	expect_close = 0;

	switch (cmd) {
	case WDIOC_GETSUPPORT:
		wdinfo.options = nowayout ?
			WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING :
			WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE;
		res = __copy_to_user(argp, &wdinfo, size) ?  -EFAULT : size;
		break;

	case WDIOC_GETSTATUS:
		break;

	case WDIOC_GETBOOTSTATUS:
		stat = (*(volatile char *) flagaddr & 0x01)
			? WDIOF_CARDRESET : 0;
		res = __copy_to_user(argp, &stat, size) ?
			-EFAULT : size;
		break;

	case WDIOC_SETOPTIONS:
		break;

	case WDIOC_KEEPALIVE:
		wdt_gpi_set_timeout(timeout);
		res = size;
		break;

	case WDIOC_SETTIMEOUT:
		{
			int val;
			if (unlikely(__copy_from_user(&val, argp, size))) {
				res = -EFAULT;
				break;
			}

			if (val > MAX_TIMEOUT_SECONDS)
				val = MAX_TIMEOUT_SECONDS;
			timeout = val;
			wdt_gpi_set_timeout(val);
			res = size;
			printk(KERN_INFO "%s: timeout set to %u seconds\n",
				wdt_gpi_name, timeout);
		}
		break;

	case WDIOC_GETTIMEOUT:
		res = __copy_to_user(argp, &timeout, size) ?
			-EFAULT : size;
		break;
	}

	return res;
}


/* Shutdown notifier */
static int
wdt_gpi_notify(struct notifier_block *this, unsigned long code, void *unused)
{
	if (code == SYS_DOWN || code == SYS_HALT)
		wdt_gpi_stop();

	return NOTIFY_DONE;
}


/* Init & exit procedures */
static const struct resource *
wdt_gpi_get_resource(struct platform_device *pdv, const char *name,
		      unsigned int type)
{
	char buf[80];
	if (snprintf(buf, sizeof buf, "%s_0", name) >= sizeof buf)
		return NULL;
	return platform_get_resource_byname(pdv, type, buf);
}

/* No hotplugging on the platform bus - use __init */
static int __init wdt_gpi_probe(struct device *dev)
{
	int res;
	struct platform_device * const pdv = to_platform_device(dev);
	const struct resource
		* const rr = wdt_gpi_get_resource(pdv, WDT_RESOURCE_REGS,
						  IORESOURCE_MEM),
		* const ri = wdt_gpi_get_resource(pdv, WDT_RESOURCE_IRQ,
						  IORESOURCE_IRQ),
		* const rc = wdt_gpi_get_resource(pdv, WDT_RESOURCE_COUNTER,
						  0);

	if (unlikely(!rr || !ri || !rc))
		return -ENXIO;

	wd_regs = ioremap_nocache(rr->start, rr->end + 1 - rr->start);
	if (unlikely(!wd_regs))
		return -ENOMEM;
	wd_irq = ri->start;
	wd_ctr = rc->start;
	res = misc_register(&miscdev);
	if (res)
		iounmap(wd_regs);
	else
		register_reboot_notifier(&wdt_gpi_shutdown);
	return res;
}

static int __exit wdt_gpi_remove(struct device *dev)
{
	int res;

	unregister_reboot_notifier(&wdt_gpi_shutdown);
	res = misc_deregister(&miscdev);
	iounmap(wd_regs);
	wd_regs = NULL;
	return res;
}


/* Device driver init & exit */
static struct device_driver wdt_gpi_driver = {
	.name		= (char *) wdt_gpi_name,
	.bus		= &platform_bus_type,
	.owner		= THIS_MODULE,
	.probe		= wdt_gpi_probe,
	.remove		= __exit_p(wdt_gpi_remove),
	.shutdown	= NULL,
	.suspend	= NULL,
	.resume		= NULL,
};

static int __init wdt_gpi_init_module(void)
{
	atomic_set(&opencnt, 1);
	if (timeout > MAX_TIMEOUT_SECONDS)
		timeout = MAX_TIMEOUT_SECONDS;
	return driver_register(&wdt_gpi_driver);
}

static void __exit wdt_gpi_cleanup_module(void)
{
	driver_unregister(&wdt_gpi_driver);
}

module_init(wdt_gpi_init_module);
module_exit(wdt_gpi_cleanup_module);

MODULE_AUTHOR("Thomas Koeller <thomas.koeller@baslerweb.com>");
MODULE_DESCRIPTION("Basler eXcite watchdog driver for gpi devices");
MODULE_VERSION("0.1");
MODULE_LICENSE("GPL");
MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
Commit	Line	Data
825d3748 TK	1	/*
	2	* Watchdog implementation for GPI h/w found on PMC-Sierra RM9xxx
	3	* chips.
	4	*
	5	* Copyright (C) 2004 by Basler Vision Technologies AG
	6	* Author: Thomas Koeller <thomas.koeller@baslerweb.com>
	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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	21	*/
	22
	23	#include <linux/platform_device.h>
	24	#include <linux/module.h>
	25	#include <linux/moduleparam.h>
	26	#include <linux/interrupt.h>
	27	#include <linux/fs.h>
	28	#include <linux/reboot.h>
d5d06ff7	29	#include <linux/notifier.h>
825d3748 TK	30	#include <linux/miscdevice.h>
	31	#include <linux/watchdog.h>
	32	#include <asm/io.h>
	33	#include <asm/atomic.h>
	34	#include <asm/processor.h>
	35	#include <asm/uaccess.h>
	36	#include <asm/system.h>
	37	#include <asm/rm9k-ocd.h>
	38
	39	#include <rm9k_wdt.h>
	40
	41
	42	#define CLOCK 125000000
	43	#define MAX_TIMEOUT_SECONDS 32
	44	#define CPCCR 0x0080
	45	#define CPGIG1SR 0x0044
	46	#define CPGIG1ER 0x0054
	47
	48
825d3748	49	/* Function prototypes */
74e86ab8	50	static irqreturn_t wdt_gpi_irqhdl(int, void *);
d5d06ff7 WVS	51	static void wdt_gpi_start(void);
d5d06ff7 WVS	52	static void wdt_gpi_stop(void);
825d3748 TK	53	static void wdt_gpi_set_timeout(unsigned int);
	54	static int wdt_gpi_open(struct inode , struct file );
	55	static int wdt_gpi_release(struct inode , struct file );
	56	static ssize_t wdt_gpi_write(struct file , const char __user , size_t, loff_t *);
	57	static long wdt_gpi_ioctl(struct file *, unsigned int, unsigned long);
825d3748	58	static int wdt_gpi_notify(struct notifier_block , unsigned long, void );
d5d06ff7	59	static const struct resource wdt_gpi_get_resource(struct platform_device , const char *, unsigned int);
97846e3c WVS	60	static int __init wdt_gpi_probe(struct device *);
97846e3c WVS	61	static int __exit wdt_gpi_remove(struct device *);
825d3748 TK	62
825d3748 TK	63
825d3748 TK	64	static const char wdt_gpi_name[] = "wdt_gpi";
	65	static atomic_t opencnt;
	66	static int expect_close;
d5d06ff7	67	static int locked;
825d3748 TK	68
825d3748 TK	69
825d3748 TK	70	/* These are set from device resources */
	71	static void __iomem * wd_regs;
	72	static unsigned int wd_irq, wd_ctr;
	73
	74
825d3748 TK	75	/* Module arguments */
	76	static int timeout = MAX_TIMEOUT_SECONDS;
	77	module_param(timeout, int, 0444);
cd57eeab WVS	78	MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds");
cd57eeab WVS	79
825d3748 TK	80	static unsigned long resetaddr = 0xbffdc200;
825d3748 TK	81	module_param(resetaddr, ulong, 0444);
cd57eeab WVS	82	MODULE_PARM_DESC(resetaddr, "Address to write to to force a reset");
cd57eeab WVS	83
825d3748 TK	84	static unsigned long flagaddr = 0xbffdc104;
825d3748 TK	85	module_param(flagaddr, ulong, 0444);
cd57eeab WVS	86	MODULE_PARM_DESC(flagaddr, "Address to write to boot flags to");
cd57eeab WVS	87
d5d06ff7	88	static int powercycle;
825d3748	89	module_param(powercycle, bool, 0444);
cd57eeab	90	MODULE_PARM_DESC(powercycle, "Cycle power if watchdog expires");
825d3748 TK	91
	92	static int nowayout = WATCHDOG_NOWAYOUT;
	93	module_param(nowayout, bool, 0444);
cd57eeab	94	MODULE_PARM_DESC(nowayout, "Watchdog cannot be disabled once started");
825d3748 TK	95
825d3748 TK	96
bec4f749	97	/* Kernel interfaces */
2b8693c0	98	static const struct file_operations fops = {
bec4f749 TK	99	.owner = THIS_MODULE,
	100	.open = wdt_gpi_open,
	101	.release = wdt_gpi_release,
	102	.write = wdt_gpi_write,
	103	.unlocked_ioctl = wdt_gpi_ioctl,
	104	};
	105
	106	static struct miscdevice miscdev = {
	107	.minor = WATCHDOG_MINOR,
	108	.name = wdt_gpi_name,
	109	.fops = &fops,
	110	};
	111
	112	static struct notifier_block wdt_gpi_shutdown = {
	113	.notifier_call = wdt_gpi_notify,
	114	};
	115
	116
97846e3c	117	/* Interrupt handler */
74e86ab8	118	static irqreturn_t wdt_gpi_irqhdl(int irq, void *ctxt)
825d3748	119	{
97846e3c WVS	120	if (!unlikely(__raw_readl(wd_regs + 0x0008) & 0x1))
	121	return IRQ_NONE;
	122	__raw_writel(0x1, wd_regs + 0x0008);
825d3748 TK	123
825d3748 TK	124
d5d06ff7	125	printk(KERN_CRIT "%s: watchdog expired - resetting system\n",
97846e3c	126	wdt_gpi_name);
825d3748	127
97846e3c WVS	128	(volatile char ) flagaddr \|= 0x01;
	129	(volatile char ) resetaddr = powercycle ? 0x01 : 0x2;
	130	iob();
	131	while (1)
	132	cpu_relax();
825d3748 TK	133	}
	134
	135
97846e3c	136	/* Watchdog functions */
414a6759 WVS	137	static void wdt_gpi_start(void)
	138	{
	139	u32 reg;
	140
	141	lock_titan_regs();
	142	reg = titan_readl(CPGIG1ER);
	143	titan_writel(reg \| (0x100 << wd_ctr), CPGIG1ER);
	144	iob();
	145	unlock_titan_regs();
	146	}
	147
	148	static void wdt_gpi_stop(void)
	149	{
	150	u32 reg;
	151
	152	lock_titan_regs();
	153	reg = titan_readl(CPCCR) & ~(0xf << (wd_ctr * 4));
	154	titan_writel(reg, CPCCR);
	155	reg = titan_readl(CPGIG1ER);
	156	titan_writel(reg & ~(0x100 << wd_ctr), CPGIG1ER);
	157	iob();
	158	unlock_titan_regs();
	159	}
	160
825d3748 TK	161	static void wdt_gpi_set_timeout(unsigned int to)
	162	{
	163	u32 reg;
	164	const u32 wdval = (to * CLOCK) & ~0x0000000f;
	165
	166	lock_titan_regs();
	167	reg = titan_readl(CPCCR) & ~(0xf << (wd_ctr * 4));
	168	titan_writel(reg, CPCCR);
	169	wmb();
	170	__raw_writel(wdval, wd_regs + 0x0000);
	171	wmb();
	172	titan_writel(reg \| (0x2 << (wd_ctr * 4)), CPCCR);
	173	wmb();
	174	titan_writel(reg \| (0x5 << (wd_ctr * 4)), CPCCR);
	175	iob();
	176	unlock_titan_regs();
	177	}
	178
	179
97846e3c	180	/* /dev/watchdog operations */
d5d06ff7	181	static int wdt_gpi_open(struct inode inode, struct file file)
825d3748 TK	182	{
825d3748 TK	183	int res;
825d3748	184
d5d06ff7	185	if (unlikely(atomic_dec_if_positive(&opencnt) < 0))
825d3748 TK	186	return -EBUSY;
	187
	188	expect_close = 0;
	189	if (locked) {
	190	module_put(THIS_MODULE);
	191	free_irq(wd_irq, &miscdev);
	192	locked = 0;
	193	}
	194
38515e90	195	res = request_irq(wd_irq, wdt_gpi_irqhdl, IRQF_SHARED \| IRQF_DISABLED,
825d3748 TK	196	wdt_gpi_name, &miscdev);
	197	if (unlikely(res))
	198	return res;
	199
	200	wdt_gpi_set_timeout(timeout);
414a6759	201	wdt_gpi_start();
825d3748 TK	202
	203	printk(KERN_INFO "%s: watchdog started, timeout = %u seconds\n",
	204	wdt_gpi_name, timeout);
d5d06ff7	205	return nonseekable_open(inode, file);
825d3748 TK	206	}
825d3748 TK	207
d5d06ff7	208	static int wdt_gpi_release(struct inode inode, struct file file)
825d3748 TK	209	{
825d3748 TK	210	if (nowayout) {
d5d06ff7	211	printk(KERN_INFO "%s: no way out - watchdog left running\n",
825d3748 TK	212	wdt_gpi_name);
	213	__module_get(THIS_MODULE);
	214	locked = 1;
	215	} else {
	216	if (expect_close) {
414a6759	217	wdt_gpi_stop();
825d3748 TK	218	free_irq(wd_irq, &miscdev);
	219	printk(KERN_INFO "%s: watchdog stopped\n", wdt_gpi_name);
	220	} else {
d5d06ff7	221	printk(KERN_CRIT "%s: unexpected close() -"
825d3748 TK	222	" watchdog left running\n",
	223	wdt_gpi_name);
	224	wdt_gpi_set_timeout(timeout);
	225	__module_get(THIS_MODULE);
	226	locked = 1;
	227	}
	228	}
	229
	230	atomic_inc(&opencnt);
	231	return 0;
	232	}
	233
825d3748 TK	234	static ssize_t
	235	wdt_gpi_write(struct file f, const char __user d, size_t s, loff_t *o)
	236	{
	237	char val;
	238
	239	wdt_gpi_set_timeout(timeout);
	240	expect_close = (s > 0) && !get_user(val, d) && (val == 'V');
	241	return s ? 1 : 0;
	242	}
	243
825d3748 TK	244	static long
	245	wdt_gpi_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
	246	{
	247	long res = -ENOTTY;
	248	const long size = _IOC_SIZE(cmd);
	249	int stat;
d5d06ff7	250	void __user argp = (void __user )arg;
825d3748 TK	251	static struct watchdog_info wdinfo = {
	252	.identity = "RM9xxx/GPI watchdog",
	253	.firmware_version = 0,
	254	.options = WDIOF_SETTIMEOUT \| WDIOF_KEEPALIVEPING
	255	};
	256
	257	if (unlikely(_IOC_TYPE(cmd) != WATCHDOG_IOCTL_BASE))
	258	return -ENOTTY;
	259
	260	if ((_IOC_DIR(cmd) & _IOC_READ)
	261	&& !access_ok(VERIFY_WRITE, arg, size))
	262	return -EFAULT;
	263
	264	if ((_IOC_DIR(cmd) & _IOC_WRITE)
	265	&& !access_ok(VERIFY_READ, arg, size))
	266	return -EFAULT;
	267
	268	expect_close = 0;
	269
	270	switch (cmd) {
	271	case WDIOC_GETSUPPORT:
	272	wdinfo.options = nowayout ?
	273	WDIOF_SETTIMEOUT \| WDIOF_KEEPALIVEPING :
	274	WDIOF_SETTIMEOUT \| WDIOF_KEEPALIVEPING \| WDIOF_MAGICCLOSE;
d5d06ff7	275	res = __copy_to_user(argp, &wdinfo, size) ? -EFAULT : size;
825d3748 TK	276	break;
	277
	278	case WDIOC_GETSTATUS:
	279	break;
	280
	281	case WDIOC_GETBOOTSTATUS:
	282	stat = ((volatile char ) flagaddr & 0x01)
	283	? WDIOF_CARDRESET : 0;
d5d06ff7	284	res = __copy_to_user(argp, &stat, size) ?
825d3748 TK	285	-EFAULT : size;
	286	break;
	287
	288	case WDIOC_SETOPTIONS:
	289	break;
	290
	291	case WDIOC_KEEPALIVE:
	292	wdt_gpi_set_timeout(timeout);
	293	res = size;
	294	break;
	295
	296	case WDIOC_SETTIMEOUT:
	297	{
	298	int val;
d5d06ff7	299	if (unlikely(__copy_from_user(&val, argp, size))) {
825d3748 TK	300	res = -EFAULT;
	301	break;
	302	}
	303
d5d06ff7 WVS	304	if (val > MAX_TIMEOUT_SECONDS)
d5d06ff7 WVS	305	val = MAX_TIMEOUT_SECONDS;
825d3748 TK	306	timeout = val;
	307	wdt_gpi_set_timeout(val);
	308	res = size;
d5d06ff7	309	printk(KERN_INFO "%s: timeout set to %u seconds\n",
825d3748 TK	310	wdt_gpi_name, timeout);
	311	}
	312	break;
	313
	314	case WDIOC_GETTIMEOUT:
d5d06ff7	315	res = __copy_to_user(argp, &timeout, size) ?
825d3748 TK	316	-EFAULT : size;
	317	break;
	318	}
	319
	320	return res;
	321	}
	322
	323
d5d06ff7	324	/* Shutdown notifier */
825d3748 TK	325	static int
	326	wdt_gpi_notify(struct notifier_block this, unsigned long code, void unused)
	327	{
414a6759 WVS	328	if (code == SYS_DOWN \|\| code == SYS_HALT)
	329	wdt_gpi_stop();
	330
825d3748 TK	331	return NOTIFY_DONE;
	332	}
	333
	334
97846e3c WVS	335	/* Init & exit procedures */
	336	static const struct resource *
	337	wdt_gpi_get_resource(struct platform_device pdv, const char name,
	338	unsigned int type)
	339	{
	340	char buf[80];
	341	if (snprintf(buf, sizeof buf, "%s_0", name) >= sizeof buf)
	342	return NULL;
	343	return platform_get_resource_byname(pdv, type, buf);
	344	}
	345
	346	/* No hotplugging on the platform bus - use __init */
	347	static int __init wdt_gpi_probe(struct device *dev)
	348	{
	349	int res;
	350	struct platform_device * const pdv = to_platform_device(dev);
	351	const struct resource
	352	* const rr = wdt_gpi_get_resource(pdv, WDT_RESOURCE_REGS,
	353	IORESOURCE_MEM),
	354	* const ri = wdt_gpi_get_resource(pdv, WDT_RESOURCE_IRQ,
	355	IORESOURCE_IRQ),
	356	* const rc = wdt_gpi_get_resource(pdv, WDT_RESOURCE_COUNTER,
	357	0);
	358
	359	if (unlikely(!rr \|\| !ri \|\| !rc))
	360	return -ENXIO;
	361
	362	wd_regs = ioremap_nocache(rr->start, rr->end + 1 - rr->start);
	363	if (unlikely(!wd_regs))
	364	return -ENOMEM;
	365	wd_irq = ri->start;
	366	wd_ctr = rc->start;
	367	res = misc_register(&miscdev);
	368	if (res)
	369	iounmap(wd_regs);
	370	else
	371	register_reboot_notifier(&wdt_gpi_shutdown);
	372	return res;
	373	}
	374
	375	static int __exit wdt_gpi_remove(struct device *dev)
	376	{
	377	int res;
	378
	379	unregister_reboot_notifier(&wdt_gpi_shutdown);
	380	res = misc_deregister(&miscdev);
	381	iounmap(wd_regs);
	382	wd_regs = NULL;
	383	return res;
	384	}
	385
	386
	387	/* Device driver init & exit */
	388	static struct device_driver wdt_gpi_driver = {
	389	.name = (char *) wdt_gpi_name,
	390	.bus = &platform_bus_type,
	391	.owner = THIS_MODULE,
	392	.probe = wdt_gpi_probe,
	393	.remove = __exit_p(wdt_gpi_remove),
	394	.shutdown = NULL,
	395	.suspend = NULL,
	396	.resume = NULL,
	397	};
825d3748 TK	398
	399	static int __init wdt_gpi_init_module(void)
	400	{
	401	atomic_set(&opencnt, 1);
	402	if (timeout > MAX_TIMEOUT_SECONDS)
	403	timeout = MAX_TIMEOUT_SECONDS;
	404	return driver_register(&wdt_gpi_driver);
	405	}
	406
825d3748 TK	407	static void __exit wdt_gpi_cleanup_module(void)
	408	{
	409	driver_unregister(&wdt_gpi_driver);
	410	}
	411
	412	module_init(wdt_gpi_init_module);
	413	module_exit(wdt_gpi_cleanup_module);
	414
825d3748 TK	415	MODULE_AUTHOR("Thomas Koeller <thomas.koeller@baslerweb.com>");
	416	MODULE_DESCRIPTION("Basler eXcite watchdog driver for gpi devices");
	417	MODULE_VERSION("0.1");
	418	MODULE_LICENSE("GPL");
	419	MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
cd57eeab	420