1 /* 2 * EISA "eeprom" support routines 3 * 4 * Copyright (C) 2001 Thomas Bogendoerfer <tsbogend at parisc-linux.org> 5 * 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License as published by 9 * the Free Software Foundation; either version 2 of the License, or 10 * (at your option) any later version. 11 * 12 * This program is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 * GNU General Public License for more details. 16 * 17 * You should have received a copy of the GNU General Public License 18 * along with this program; if not, write to the Free Software 19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 20 */ 21 22 #include <linux/module.h> 23 #include <linux/init.h> 24 #include <linux/kernel.h> 25 #include <linux/miscdevice.h> 26 #include <linux/slab.h> 27 #include <linux/smp_lock.h> 28 #include <linux/fs.h> 29 #include <asm/io.h> 30 #include <asm/uaccess.h> 31 #include <asm/eisa_eeprom.h> 32 33 #define EISA_EEPROM_MINOR 241 34 35 static loff_t eisa_eeprom_llseek(struct file *file, loff_t offset, int origin ) 36 { 37 switch (origin) { 38 case 0: 39 /* nothing to do */ 40 break; 41 case 1: 42 offset += file->f_pos; 43 break; 44 case 2: 45 offset += HPEE_MAX_LENGTH; 46 break; 47 } 48 return (offset >= 0 && offset < HPEE_MAX_LENGTH) ? (file->f_pos = offset) : -EINVAL; 49 } 50 51 static ssize_t eisa_eeprom_read(struct file * file, 52 char __user *buf, size_t count, loff_t *ppos ) 53 { 54 unsigned char *tmp; 55 ssize_t ret; 56 int i; 57 58 if (*ppos >= HPEE_MAX_LENGTH) 59 return 0; 60 61 count = *ppos + count < HPEE_MAX_LENGTH ? count : HPEE_MAX_LENGTH - *ppos; 62 tmp = kmalloc(count, GFP_KERNEL); 63 if (tmp) { 64 for (i = 0; i < count; i++) 65 tmp[i] = readb(eisa_eeprom_addr+(*ppos)++); 66 67 if (copy_to_user (buf, tmp, count)) 68 ret = -EFAULT; 69 else 70 ret = count; 71 kfree (tmp); 72 } else 73 ret = -ENOMEM; 74 75 return ret; 76 } 77 78 static int eisa_eeprom_ioctl(struct inode *inode, struct file *file, 79 unsigned int cmd, 80 unsigned long arg) 81 { 82 return -ENOTTY; 83 } 84 85 static int eisa_eeprom_open(struct inode *inode, struct file *file) 86 { 87 cycle_kernel_lock(); 88 89 if (file->f_mode & FMODE_WRITE) 90 return -EINVAL; 91 92 return 0; 93 } 94 95 static int eisa_eeprom_release(struct inode *inode, struct file *file) 96 { 97 return 0; 98 } 99 100 /* 101 * The various file operations we support. 102 */ 103 static const struct file_operations eisa_eeprom_fops = { 104 .owner = THIS_MODULE, 105 .llseek = eisa_eeprom_llseek, 106 .read = eisa_eeprom_read, 107 .ioctl = eisa_eeprom_ioctl, 108 .open = eisa_eeprom_open, 109 .release = eisa_eeprom_release, 110 }; 111 112 static struct miscdevice eisa_eeprom_dev = { 113 EISA_EEPROM_MINOR, 114 "eisa_eeprom", 115 &eisa_eeprom_fops 116 }; 117 118 static int __init eisa_eeprom_init(void) 119 { 120 int retval; 121 122 if (!eisa_eeprom_addr) 123 return -ENODEV; 124 125 retval = misc_register(&eisa_eeprom_dev); 126 if (retval < 0) { 127 printk(KERN_ERR "EISA EEPROM: cannot register misc device.\n"); 128 return retval; 129 } 130 131 printk(KERN_INFO "EISA EEPROM at 0x%p\n", eisa_eeprom_addr); 132 return 0; 133 } 134 135 MODULE_LICENSE("GPL"); 136 137 module_init(eisa_eeprom_init); 138