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1// SPDX-License-Identifier: GPL-2.0-or-later2/* 3 * EISA "eeprom" support routines4 *5 * Copyright (C) 2001 Thomas Bogendoerfer <tsbogend at parisc-linux.org>6 */7 8#include <linux/module.h>9#include <linux/init.h>10#include <linux/kernel.h>11#include <linux/miscdevice.h>12#include <linux/slab.h>13#include <linux/fs.h>14#include <asm/io.h>15#include <linux/uaccess.h>16#include <asm/eisa_eeprom.h>17 18#define EISA_EEPROM_MINOR 24119 20static loff_t eisa_eeprom_llseek(struct file *file, loff_t offset, int origin)21{22 return fixed_size_llseek(file, offset, origin, HPEE_MAX_LENGTH);23}24 25static ssize_t eisa_eeprom_read(struct file * file,26 char __user *buf, size_t count, loff_t *ppos )27{28 unsigned char *tmp;29 ssize_t ret;30 int i;31 32 if (*ppos < 0 || *ppos >= HPEE_MAX_LENGTH)33 return 0;34 35 count = *ppos + count < HPEE_MAX_LENGTH ? count : HPEE_MAX_LENGTH - *ppos;36 tmp = kmalloc(count, GFP_KERNEL);37 if (tmp) {38 for (i = 0; i < count; i++)39 tmp[i] = readb(eisa_eeprom_addr+(*ppos)++);40 41 if (copy_to_user (buf, tmp, count))42 ret = -EFAULT;43 else44 ret = count;45 kfree (tmp);46 } else47 ret = -ENOMEM;48 49 return ret;50}51 52static int eisa_eeprom_open(struct inode *inode, struct file *file)53{54 if (file->f_mode & FMODE_WRITE)55 return -EINVAL;56 57 return 0;58}59 60static int eisa_eeprom_release(struct inode *inode, struct file *file)61{62 return 0;63}64 65/*66 * The various file operations we support.67 */68static const struct file_operations eisa_eeprom_fops = {69 .owner = THIS_MODULE,70 .llseek = eisa_eeprom_llseek,71 .read = eisa_eeprom_read,72 .open = eisa_eeprom_open,73 .release = eisa_eeprom_release,74};75 76static struct miscdevice eisa_eeprom_dev = {77 EISA_EEPROM_MINOR,78 "eisa_eeprom",79 &eisa_eeprom_fops80};81 82static int __init eisa_eeprom_init(void)83{84 int retval;85 86 if (!eisa_eeprom_addr)87 return -ENODEV;88 89 retval = misc_register(&eisa_eeprom_dev);90 if (retval < 0) {91 printk(KERN_ERR "EISA EEPROM: cannot register misc device.\n");92 return retval;93 }94 95 printk(KERN_INFO "EISA EEPROM at 0x%px\n", eisa_eeprom_addr);96 return 0;97}98 99MODULE_LICENSE("GPL");100 101module_init(eisa_eeprom_init);102