/* *	Timer Counter interface for Linux on Atmel AT91RM9200 * *	Copyright (c) 2002 Rick Bronson *  *	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. *Watchdog driver.  This enables you to open a Watchdog and change thetime for the watchdog to expire. */#include <linux/module.h>#include <linux/fs.h>#include <linux/miscdevice.h>#include <linux/string.h>#include <linux/init.h>#include <linux/poll.h>#include <linux/proc_fs.h>#include <asm/bitops.h>#include <asm/hardware.h>#include <asm/irq.h>#include <asm/arch/watchdog.h>  /* get ioctl stuff for watchdog */extern struct watchdog_private watchdog_priv;  /* watchdog private stuff */#define	DRIVER_VERSION	"1.00"static int at91_watchdog_open(struct inode *inode, struct file *file){	file->private_data = &watchdog_priv;	spin_lock_init(&priv->lock1);        MOD_INC_USE_COUNT;        return 0;}static int at91_watchdog_release(struct inode *inode, struct file *file){        MOD_DEC_USE_COUNT;	return 0;}ssize_t at91_watchdog_write(struct file * file, const char *buf, size_t count, loff_t * ppos)  {#if 0  /* not sure if they want to use it this way */  AT91PS_ST pSt;  /* pointer to the ST peripheral */  struct at91_watchdog_ioctl_set watchdog_set;  if (verify_area(VERIFY_READ, buf, count))    return -EFAULT;  if (__get_user(watchdog_set, buf))    return -EFAULT;  pSt = AT91C_BASE_ST;  pSt->ST_WDMR = watchdog_set.watchdog_wdmr | AT91C_ST_RSTEN;  /* (ST) Reset Enable */  pSt->ST_CR = AT91C_ST_WDRST;  /* (ST) Watchdog Timer Restart */#endif  return count;  }/* * Handle commands from user-space */static int at91_watchdog_ioctl(struct inode *inode, struct file *file,			  unsigned int cmd, unsigned long arg)  {  AT91PS_ST pSt;  /* pointer to the ST peripheral */  unsigned long flags;  struct watchdog_private *priv = (struct watchdog_private *)file->private_data;  struct at91_watchdog_ioctl_set watchdog_set;  struct at91_watchdog_ioctl_timer watchdog_timer;  long long all_64bits;  /* upper 44 bits to make 64 bit timer */  AT91_REG crtr, crtr_save;  /* saved value from AT91C_ST_CRTR (20 bits) */  int ret = 0;  pSt = AT91C_BASE_ST;  switch (cmd)    {    case AT91_WATCHDOG_SET_WATCHDOG:  /* set and enable the watchdog */      if (copy_from_user (&watchdog_set, (void *)arg, sizeof (watchdog_set)))        return -EFAULT;      pSt->ST_WDMR = watchdog_set.watchdog_wdmr | AT91C_ST_RSTEN;  /* (ST) Reset Enable */      pSt->ST_CR = AT91C_ST_WDRST;  /* (ST) Watchdog Timer Restart */      break;    case AT91_WATCHDOG_GET_32768_TIMER:  /* get the timer */      spin_lock_irqsave(&priv->lock1, flags);  /* stop int's while we                         read values that could be changed in the interrupt */      crtr = pSt->ST_CRTR;  /* 20 ls bits of 32768 Hz clock */      crtr_save = priv->crtr_save;      all_64bits = priv->upper_44bits;  /* get temp copy */      spin_unlock_irqrestore(&priv->lock1, flags);      if (crtr < crtr_save)  /* if wrapped, add one to upper bits */        all_64bits += AT91C_ST_CRTV + 1;      all_64bits |= crtr;      ret = copy_to_user ((void *)arg, &all_64bits, sizeof (watchdog_timer)) ? -EFAULT : 0;      break;    default:      ret = -EINVAL;      break;    }  return ret;  }static struct file_operations at91_watchdog_fops = {	owner:THIS_MODULE,	write:at91_watchdog_write,	ioctl:at91_watchdog_ioctl,	open:at91_watchdog_open,	release:at91_watchdog_release,};static struct miscdevice watchdog_miscdev ={	WATCHDOG_MINOR,	"at91 watchdog",	&at91_watchdog_fops};#/* * Initialize and install WATCHDOG driver */static int __init at91_watchdog_init(void)  {  int res;   res = misc_register (&watchdog_miscdev);  if (res < 0)    {    printk(KERN_ERR "at91_watchdog: couldn't get a major number.\n");    return res;    }  printk(KERN_INFO "AT91 Watchdog driver v" DRIVER_VERSION "\n");  return 0;  }module_init(at91_watchdog_init);MODULE_AUTHOR("Rick Bronson");MODULE_DESCRIPTION("AT91 Timer Counter Driver (AT91_WATCHDOG)");EXPORT_NO_SYMBOLS;