drivers/sbus/char/riowatchdog.c - kernel/msm - Gitiles

 /* $Id: riowatchdog.c,v 1.3.2.2 2002/01/23 18:48:02 davem Exp $
  * riowatchdog.c - driver for hw watchdog inside Super I/O of RIO
  *
  * Copyright (C) 2001 David S. Miller (davem@redhat.com)
  */

 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/types.h>
 #include <linux/fs.h>
 #include <linux/errno.h>
 #include <linux/init.h>
 #include <linux/miscdevice.h>

 #include <asm/io.h>
 #include <asm/ebus.h>
 #include <asm/bbc.h>
 #include <asm/oplib.h>
 #include <asm/uaccess.h>

 #include <asm/watchdog.h>

 /* RIO uses the NatSemi Super I/O power management logical device
  * as its' watchdog.
  *
  * When the watchdog triggers, it asserts a line to the BBC (Boot Bus
  * Controller) of the machine.  The BBC can only be configured to
  * trigger a power-on reset when the signal is asserted.  The BBC
  * can be configured to ignore the signal entirely as well.
  *
  * The only Super I/O device register we care about is at index
  * 0x05 (WDTO_INDEX) which is the watchdog time-out in minutes (1-255).
  * If set to zero, this disables the watchdog.  When set, the system
  * must periodically (before watchdog expires) clear (set to zero) and
  * re-set the watchdog else it will trigger.
  *
  * There are two other indexed watchdog registers inside this Super I/O
  * logical device, but they are unused.  The first, at index 0x06 is
  * the watchdog control and can be used to make the watchdog timer re-set
  * when the PS/2 mouse or serial lines show activity.  The second, at
  * index 0x07 is merely a sampling of the line from the watchdog to the
  * BBC.
  *
  * The watchdog device generates no interrupts.
  */

 MODULE_AUTHOR("David S. Miller <davem@redhat.com>");
 MODULE_DESCRIPTION("Hardware watchdog driver for Sun RIO");
 MODULE_SUPPORTED_DEVICE("watchdog");
 MODULE_LICENSE("GPL");

 #define RIOWD_NAME	"pmc"
 #define RIOWD_MINOR	215

 static DEFINE_SPINLOCK(riowd_lock);

 static void __iomem *bbc_regs;
 static void __iomem *riowd_regs;
 #define WDTO_INDEX	0x05

 static int riowd_timeout = 1;		/* in minutes */
 module_param(riowd_timeout, int, 0);
 MODULE_PARM_DESC(riowd_timeout, "Watchdog timeout in minutes");

 #if 0 /* Currently unused. */
 static u8 riowd_readreg(int index)
 {
 	unsigned long flags;
 	u8 ret;

 	spin_lock_irqsave(&riowd_lock, flags);
 	writeb(index, riowd_regs + 0);
 	ret = readb(riowd_regs + 1);
 	spin_unlock_irqrestore(&riowd_lock, flags);

 	return ret;
 }
 #endif

 static void riowd_writereg(u8 val, int index)
 {
 	unsigned long flags;

 	spin_lock_irqsave(&riowd_lock, flags);
 	writeb(index, riowd_regs + 0);
 	writeb(val, riowd_regs + 1);
 	spin_unlock_irqrestore(&riowd_lock, flags);
 }

 static void riowd_pingtimer(void)
 {
 	riowd_writereg(riowd_timeout, WDTO_INDEX);
 }

 static void riowd_stoptimer(void)
 {
 	u8 val;

 	riowd_writereg(0, WDTO_INDEX);

 	val = readb(bbc_regs + BBC_WDACTION);
 	val &= ~BBC_WDACTION_RST;
 	writeb(val, bbc_regs + BBC_WDACTION);
 }

 static void riowd_starttimer(void)
 {
 	u8 val;

 	riowd_writereg(riowd_timeout, WDTO_INDEX);

 	val = readb(bbc_regs + BBC_WDACTION);
 	val |= BBC_WDACTION_RST;
 	writeb(val, bbc_regs + BBC_WDACTION);
 }

 static int riowd_open(struct inode *inode, struct file *filp)
 {
 	nonseekable_open(inode, filp);
 	return 0;
 }

 static int riowd_release(struct inode *inode, struct file *filp)
 {
 	return 0;
 }

 static int riowd_ioctl(struct inode *inode, struct file *filp,
 		       unsigned int cmd, unsigned long arg)
 {
 	static struct watchdog_info info = {
 	       	WDIOF_SETTIMEOUT, 0, "Natl. Semiconductor PC97317"
 	};
 	void __user *argp = (void __user *)arg;
 	unsigned int options;
 	int new_margin;

 	switch (cmd) {
 	case WDIOC_GETSUPPORT:
 		if (copy_to_user(argp, &info, sizeof(info)))
 			return -EFAULT;
 		break;

 	case WDIOC_GETSTATUS:
 	case WDIOC_GETBOOTSTATUS:
 		if (put_user(0, (int __user *)argp))
 			return -EFAULT;
 		break;

 	case WDIOC_KEEPALIVE:
 		riowd_pingtimer();
 		break;

 	case WDIOC_SETOPTIONS:
 		if (copy_from_user(&options, argp, sizeof(options)))
 			return -EFAULT;

 		if (options & WDIOS_DISABLECARD)
 			riowd_stoptimer();
 		else if (options & WDIOS_ENABLECARD)
 			riowd_starttimer();
 		else
 			return -EINVAL;

 		break;

 	case WDIOC_SETTIMEOUT:
 		if (get_user(new_margin, (int __user *)argp))
 			return -EFAULT;
 		if ((new_margin < 60) || (new_margin > (255 * 60)))
 		    return -EINVAL;
 		riowd_timeout = (new_margin + 59) / 60;
 		riowd_pingtimer();
 		/* Fall */

 	case WDIOC_GETTIMEOUT:
 		return put_user(riowd_timeout * 60, (int __user *)argp);

 	default:
 		return -EINVAL;
 	};

 	return 0;
 }

 static ssize_t riowd_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
 {
 	if (count) {
 		riowd_pingtimer();
 		return 1;
 	}

 	return 0;
 }

 static struct file_operations riowd_fops = {
 	.owner =	THIS_MODULE,
 	.ioctl =	riowd_ioctl,
 	.open =		riowd_open,
 	.write =	riowd_write,
 	.release =	riowd_release,
 };

 static struct miscdevice riowd_miscdev = { RIOWD_MINOR, RIOWD_NAME, &riowd_fops };

 static int __init riowd_bbc_init(void)
 {
 	struct 	linux_ebus *ebus = NULL;
 	struct 	linux_ebus_device *edev = NULL;
 	u8 val;

 	for_each_ebus(ebus) {
 		for_each_ebusdev(edev, ebus) {
 			if (!strcmp(edev->prom_name, "bbc"))
 				goto found_bbc;
 		}
 	}

 found_bbc:
 	if (!edev)
 		return -ENODEV;
 	bbc_regs = ioremap(edev->resource[0].start, BBC_REGS_SIZE);
 	if (!bbc_regs)
 		return -ENODEV;

 	/* Turn it off. */
 	val = readb(bbc_regs + BBC_WDACTION);
 	val &= ~BBC_WDACTION_RST;
 	writeb(val, bbc_regs + BBC_WDACTION);

 	return 0;
 }

 static int __init riowd_init(void)
 {
 	struct 	linux_ebus *ebus = NULL;
 	struct 	linux_ebus_device *edev = NULL;

 	for_each_ebus(ebus) {
 		for_each_ebusdev(edev, ebus) {
 			if (!strcmp(edev->prom_name, RIOWD_NAME))
 				goto ebus_done;
 		}
 	}

 ebus_done:
 	if (!edev)
 		goto fail;

 	riowd_regs = ioremap(edev->resource[0].start, 2);
 	if (riowd_regs == NULL) {
 		printk(KERN_ERR "pmc: Cannot map registers.\n");
 		return -ENODEV;
 	}

 	if (riowd_bbc_init()) {
 		printk(KERN_ERR "pmc: Failure initializing BBC config.\n");
 		goto fail;
 	}

 	if (misc_register(&riowd_miscdev)) {
 		printk(KERN_ERR "pmc: Cannot register watchdog misc device.\n");
 		goto fail;
 	}

 	printk(KERN_INFO "pmc: Hardware watchdog [%i minutes], "
 	       "regs at %p\n", riowd_timeout, riowd_regs);

 	return 0;

 fail:
 	if (riowd_regs) {
 		iounmap(riowd_regs);
 		riowd_regs = NULL;
 	}
 	if (bbc_regs) {
 		iounmap(bbc_regs);
 		bbc_regs = NULL;
 	}
 	return -ENODEV;
 }

 static void __exit riowd_cleanup(void)
 {
 	misc_deregister(&riowd_miscdev);
 	iounmap(riowd_regs);
 	riowd_regs = NULL;
 	iounmap(bbc_regs);
 	bbc_regs = NULL;
 }

 module_init(riowd_init);
 module_exit(riowd_cleanup);
	/* $Id: riowatchdog.c,v 1.3.2.2 2002/01/23 18:48:02 davem Exp $
	* riowatchdog.c - driver for hw watchdog inside Super I/O of RIO
	*
	* Copyright (C) 2001 David S. Miller (davem@redhat.com)
	*/

	#include <linux/kernel.h>
	#include <linux/module.h>
	#include <linux/types.h>
	#include <linux/fs.h>
	#include <linux/errno.h>
	#include <linux/init.h>
	#include <linux/miscdevice.h>

	#include <asm/io.h>
	#include <asm/ebus.h>
	#include <asm/bbc.h>
	#include <asm/oplib.h>
	#include <asm/uaccess.h>

	#include <asm/watchdog.h>

	/* RIO uses the NatSemi Super I/O power management logical device
	* as its' watchdog.
	*
	* When the watchdog triggers, it asserts a line to the BBC (Boot Bus
	* Controller) of the machine. The BBC can only be configured to
	* trigger a power-on reset when the signal is asserted. The BBC
	* can be configured to ignore the signal entirely as well.
	*
	* The only Super I/O device register we care about is at index
	* 0x05 (WDTO_INDEX) which is the watchdog time-out in minutes (1-255).
	* If set to zero, this disables the watchdog. When set, the system
	* must periodically (before watchdog expires) clear (set to zero) and
	* re-set the watchdog else it will trigger.
	*
	* There are two other indexed watchdog registers inside this Super I/O
	* logical device, but they are unused. The first, at index 0x06 is
	* the watchdog control and can be used to make the watchdog timer re-set
	* when the PS/2 mouse or serial lines show activity. The second, at
	* index 0x07 is merely a sampling of the line from the watchdog to the
	* BBC.
	*
	* The watchdog device generates no interrupts.
	*/

	MODULE_AUTHOR("David S. Miller <davem@redhat.com>");
	MODULE_DESCRIPTION("Hardware watchdog driver for Sun RIO");
	MODULE_SUPPORTED_DEVICE("watchdog");
	MODULE_LICENSE("GPL");

	#define RIOWD_NAME "pmc"
	#define RIOWD_MINOR 215

	static DEFINE_SPINLOCK(riowd_lock);

	static void __iomem *bbc_regs;
	static void __iomem *riowd_regs;
	#define WDTO_INDEX 0x05

	static int riowd_timeout = 1; /* in minutes */
	module_param(riowd_timeout, int, 0);
	MODULE_PARM_DESC(riowd_timeout, "Watchdog timeout in minutes");

	#if 0 /* Currently unused. */
	static u8 riowd_readreg(int index)
	{
	unsigned long flags;
	u8 ret;

	spin_lock_irqsave(&riowd_lock, flags);
	writeb(index, riowd_regs + 0);
	ret = readb(riowd_regs + 1);
	spin_unlock_irqrestore(&riowd_lock, flags);

	return ret;
	}
	#endif

	static void riowd_writereg(u8 val, int index)
	{
	unsigned long flags;

	spin_lock_irqsave(&riowd_lock, flags);
	writeb(index, riowd_regs + 0);
	writeb(val, riowd_regs + 1);
	spin_unlock_irqrestore(&riowd_lock, flags);
	}

	static void riowd_pingtimer(void)
	{
	riowd_writereg(riowd_timeout, WDTO_INDEX);
	}

	static void riowd_stoptimer(void)
	{
	u8 val;

	riowd_writereg(0, WDTO_INDEX);

	val = readb(bbc_regs + BBC_WDACTION);
	val &= ~BBC_WDACTION_RST;
	writeb(val, bbc_regs + BBC_WDACTION);
	}

	static void riowd_starttimer(void)
	{
	u8 val;

	riowd_writereg(riowd_timeout, WDTO_INDEX);

	val = readb(bbc_regs + BBC_WDACTION);
	val \|= BBC_WDACTION_RST;
	writeb(val, bbc_regs + BBC_WDACTION);
	}

	static int riowd_open(struct inode inode, struct file filp)
	{
	nonseekable_open(inode, filp);
	return 0;
	}

	static int riowd_release(struct inode inode, struct file filp)
	{
	return 0;
	}

	static int riowd_ioctl(struct inode inode, struct file filp,
	unsigned int cmd, unsigned long arg)
	{
	static struct watchdog_info info = {
	WDIOF_SETTIMEOUT, 0, "Natl. Semiconductor PC97317"
	};
	void __user argp = (void __user )arg;
	unsigned int options;
	int new_margin;

	switch (cmd) {
	case WDIOC_GETSUPPORT:
	if (copy_to_user(argp, &info, sizeof(info)))
	return -EFAULT;
	break;

	case WDIOC_GETSTATUS:
	case WDIOC_GETBOOTSTATUS:
	if (put_user(0, (int __user *)argp))
	return -EFAULT;
	break;

	case WDIOC_KEEPALIVE:
	riowd_pingtimer();
	break;

	case WDIOC_SETOPTIONS:
	if (copy_from_user(&options, argp, sizeof(options)))
	return -EFAULT;

	if (options & WDIOS_DISABLECARD)
	riowd_stoptimer();
	else if (options & WDIOS_ENABLECARD)
	riowd_starttimer();
	else
	return -EINVAL;

	break;

	case WDIOC_SETTIMEOUT:
	if (get_user(new_margin, (int __user *)argp))
	return -EFAULT;
	if ((new_margin < 60) \|\| (new_margin > (255 * 60)))
	return -EINVAL;
	riowd_timeout = (new_margin + 59) / 60;
	riowd_pingtimer();
	/* Fall */

	case WDIOC_GETTIMEOUT:
	return put_user(riowd_timeout * 60, (int __user *)argp);

	default:
	return -EINVAL;
	};

	return 0;
	}

	static ssize_t riowd_write(struct file file, const char __user buf, size_t count, loff_t *ppos)
	{
	if (count) {
	riowd_pingtimer();
	return 1;
	}

	return 0;
	}

	static struct file_operations riowd_fops = {
	.owner = THIS_MODULE,
	.ioctl = riowd_ioctl,
	.open = riowd_open,
	.write = riowd_write,
	.release = riowd_release,
	};

	static struct miscdevice riowd_miscdev = { RIOWD_MINOR, RIOWD_NAME, &riowd_fops };

	static int __init riowd_bbc_init(void)
	{
	struct linux_ebus *ebus = NULL;
	struct linux_ebus_device *edev = NULL;
	u8 val;

	for_each_ebus(ebus) {
	for_each_ebusdev(edev, ebus) {
	if (!strcmp(edev->prom_name, "bbc"))
	goto found_bbc;
	}
	}

	found_bbc:
	if (!edev)
	return -ENODEV;
	bbc_regs = ioremap(edev->resource[0].start, BBC_REGS_SIZE);
	if (!bbc_regs)
	return -ENODEV;

	/* Turn it off. */
	val = readb(bbc_regs + BBC_WDACTION);
	val &= ~BBC_WDACTION_RST;
	writeb(val, bbc_regs + BBC_WDACTION);

	return 0;
	}

	static int __init riowd_init(void)
	{
	struct linux_ebus *ebus = NULL;
	struct linux_ebus_device *edev = NULL;

	for_each_ebus(ebus) {
	for_each_ebusdev(edev, ebus) {
	if (!strcmp(edev->prom_name, RIOWD_NAME))
	goto ebus_done;
	}
	}

	ebus_done:
	if (!edev)
	goto fail;

	riowd_regs = ioremap(edev->resource[0].start, 2);
	if (riowd_regs == NULL) {
	printk(KERN_ERR "pmc: Cannot map registers.\n");
	return -ENODEV;
	}

	if (riowd_bbc_init()) {
	printk(KERN_ERR "pmc: Failure initializing BBC config.\n");
	goto fail;
	}

	if (misc_register(&riowd_miscdev)) {
	printk(KERN_ERR "pmc: Cannot register watchdog misc device.\n");
	goto fail;
	}

	printk(KERN_INFO "pmc: Hardware watchdog [%i minutes], "
	"regs at %p\n", riowd_timeout, riowd_regs);

	return 0;

	fail:
	if (riowd_regs) {
	iounmap(riowd_regs);
	riowd_regs = NULL;
	}
	if (bbc_regs) {
	iounmap(bbc_regs);
	bbc_regs = NULL;
	}
	return -ENODEV;
	}

	static void __exit riowd_cleanup(void)
	{
	misc_deregister(&riowd_miscdev);
	iounmap(riowd_regs);
	riowd_regs = NULL;
	iounmap(bbc_regs);
	bbc_regs = NULL;
	}

	module_init(riowd_init);
	module_exit(riowd_cleanup);