/* 
   *    EISA "eeprom" support routines
   *
   *    Copyright (C) 2001 Thomas Bogendoerfer <tsbogend at parisc-linux.org>
   *
   *
   *    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/module.h>
  #include <linux/init.h>
  #include <linux/kernel.h>
  #include <linux/miscdevice.h>
  #include <linux/slab.h>
  #include <linux/fs.h>
  #include <asm/io.h>
  #include <asm/uaccess.h>
  #include <asm/eisa_eeprom.h>
  
  #define 	EISA_EEPROM_MINOR 241
  
  static loff_t eisa_eeprom_llseek(struct file *file, loff_t offset, int origin )
  {
  	switch (origin) {
  	  case 0:
  		/* nothing to do */
  		break;
  	  case 1:
  		offset += file->f_pos;
  		break;
  	  case 2:
  		offset += HPEE_MAX_LENGTH;
  		break;
  	}
  	return (offset >= 0 && offset < HPEE_MAX_LENGTH) ? (file->f_pos = offset) : -EINVAL;
  }
  
  static ssize_t eisa_eeprom_read(struct file * file,

  			      char __user *buf, size_t count, loff_t *ppos )

  {
  	unsigned char *tmp;
  	ssize_t ret;
  	int i;
  	

  	if (*ppos < 0 || *ppos >= HPEE_MAX_LENGTH)

  		return 0;
  	
  	count = *ppos + count < HPEE_MAX_LENGTH ? count : HPEE_MAX_LENGTH - *ppos;
  	tmp = kmalloc(count, GFP_KERNEL);
  	if (tmp) {
  		for (i = 0; i < count; i++)
  			tmp[i] = readb(eisa_eeprom_addr+(*ppos)++);
  
  		if (copy_to_user (buf, tmp, count))
  			ret = -EFAULT;
  		else
  			ret = count;
  		kfree (tmp);
  	} else
  		ret = -ENOMEM;
  	
  	return ret;
  }

  static int eisa_eeprom_open(struct inode *inode, struct file *file)
  {

  	if (file->f_mode & FMODE_WRITE)

  		return -EINVAL;
     
  	return 0;
  }
  
  static int eisa_eeprom_release(struct inode *inode, struct file *file)
  {
  	return 0;
  }
  
  /*
   *	The various file operations we support.
   */

  static const struct file_operations eisa_eeprom_fops = {

  	.owner =	THIS_MODULE,
  	.llseek =	eisa_eeprom_llseek,
  	.read =		eisa_eeprom_read,

  	.open =		eisa_eeprom_open,
  	.release =	eisa_eeprom_release,
  };
  
  static struct miscdevice eisa_eeprom_dev = {
  	EISA_EEPROM_MINOR,
  	"eisa_eeprom",
  	&eisa_eeprom_fops
  };
  
  static int __init eisa_eeprom_init(void)
  {
  	int retval;
  
  	if (!eisa_eeprom_addr)
  		return -ENODEV;
  
  	retval = misc_register(&eisa_eeprom_dev);
  	if (retval < 0) {
  		printk(KERN_ERR "EISA EEPROM: cannot register misc device.
  ");
  		return retval;
  	}
  
  	printk(KERN_INFO "EISA EEPROM at 0x%p
  ", eisa_eeprom_addr);
  	return 0;
  }
  
  MODULE_LICENSE("GPL");
  
  module_init(eisa_eeprom_init);