11a59d1b8SThomas Gleixner // SPDX-License-Identifier: GPL-2.0-or-later
21da177e4SLinus Torvalds /*
31da177e4SLinus Torvalds * EISA "eeprom" support routines
41da177e4SLinus Torvalds *
51da177e4SLinus Torvalds * Copyright (C) 2001 Thomas Bogendoerfer <tsbogend at parisc-linux.org>
61da177e4SLinus Torvalds */
71da177e4SLinus Torvalds
81da177e4SLinus Torvalds #include <linux/module.h>
91da177e4SLinus Torvalds #include <linux/init.h>
101da177e4SLinus Torvalds #include <linux/kernel.h>
111da177e4SLinus Torvalds #include <linux/miscdevice.h>
121da177e4SLinus Torvalds #include <linux/slab.h>
131da177e4SLinus Torvalds #include <linux/fs.h>
141da177e4SLinus Torvalds #include <asm/io.h>
157c0f6ba6SLinus Torvalds #include <linux/uaccess.h>
161da177e4SLinus Torvalds #include <asm/eisa_eeprom.h>
171da177e4SLinus Torvalds
181da177e4SLinus Torvalds #define EISA_EEPROM_MINOR 241
191da177e4SLinus Torvalds
eisa_eeprom_llseek(struct file * file,loff_t offset,int origin)201da177e4SLinus Torvalds static loff_t eisa_eeprom_llseek(struct file *file, loff_t offset, int origin)
211da177e4SLinus Torvalds {
2274797797SAl Viro return fixed_size_llseek(file, offset, origin, HPEE_MAX_LENGTH);
231da177e4SLinus Torvalds }
241da177e4SLinus Torvalds
eisa_eeprom_read(struct file * file,char __user * buf,size_t count,loff_t * ppos)251da177e4SLinus Torvalds static ssize_t eisa_eeprom_read(struct file * file,
2645dbe914SAlexey Dobriyan char __user *buf, size_t count, loff_t *ppos )
271da177e4SLinus Torvalds {
281da177e4SLinus Torvalds unsigned char *tmp;
291da177e4SLinus Torvalds ssize_t ret;
301da177e4SLinus Torvalds int i;
311da177e4SLinus Torvalds
326b4dbcd8SMichael Buesch if (*ppos < 0 || *ppos >= HPEE_MAX_LENGTH)
331da177e4SLinus Torvalds return 0;
341da177e4SLinus Torvalds
351da177e4SLinus Torvalds count = *ppos + count < HPEE_MAX_LENGTH ? count : HPEE_MAX_LENGTH - *ppos;
361da177e4SLinus Torvalds tmp = kmalloc(count, GFP_KERNEL);
371da177e4SLinus Torvalds if (tmp) {
381da177e4SLinus Torvalds for (i = 0; i < count; i++)
391da177e4SLinus Torvalds tmp[i] = readb(eisa_eeprom_addr+(*ppos)++);
401da177e4SLinus Torvalds
411da177e4SLinus Torvalds if (copy_to_user (buf, tmp, count))
421da177e4SLinus Torvalds ret = -EFAULT;
431da177e4SLinus Torvalds else
441da177e4SLinus Torvalds ret = count;
451da177e4SLinus Torvalds kfree (tmp);
461da177e4SLinus Torvalds } else
471da177e4SLinus Torvalds ret = -ENOMEM;
481da177e4SLinus Torvalds
491da177e4SLinus Torvalds return ret;
501da177e4SLinus Torvalds }
511da177e4SLinus Torvalds
eisa_eeprom_open(struct inode * inode,struct file * file)521da177e4SLinus Torvalds static int eisa_eeprom_open(struct inode *inode, struct file *file)
531da177e4SLinus Torvalds {
54aeb5d727SAl Viro if (file->f_mode & FMODE_WRITE)
551da177e4SLinus Torvalds return -EINVAL;
561da177e4SLinus Torvalds
571da177e4SLinus Torvalds return 0;
581da177e4SLinus Torvalds }
591da177e4SLinus Torvalds
eisa_eeprom_release(struct inode * inode,struct file * file)601da177e4SLinus Torvalds static int eisa_eeprom_release(struct inode *inode, struct file *file)
611da177e4SLinus Torvalds {
621da177e4SLinus Torvalds return 0;
631da177e4SLinus Torvalds }
641da177e4SLinus Torvalds
651da177e4SLinus Torvalds /*
661da177e4SLinus Torvalds * The various file operations we support.
671da177e4SLinus Torvalds */
68d54b1fdbSArjan van de Ven static const struct file_operations eisa_eeprom_fops = {
691da177e4SLinus Torvalds .owner = THIS_MODULE,
701da177e4SLinus Torvalds .llseek = eisa_eeprom_llseek,
711da177e4SLinus Torvalds .read = eisa_eeprom_read,
721da177e4SLinus Torvalds .open = eisa_eeprom_open,
731da177e4SLinus Torvalds .release = eisa_eeprom_release,
741da177e4SLinus Torvalds };
751da177e4SLinus Torvalds
761da177e4SLinus Torvalds static struct miscdevice eisa_eeprom_dev = {
771da177e4SLinus Torvalds EISA_EEPROM_MINOR,
781da177e4SLinus Torvalds "eisa_eeprom",
791da177e4SLinus Torvalds &eisa_eeprom_fops
801da177e4SLinus Torvalds };
811da177e4SLinus Torvalds
eisa_eeprom_init(void)821da177e4SLinus Torvalds static int __init eisa_eeprom_init(void)
831da177e4SLinus Torvalds {
841da177e4SLinus Torvalds int retval;
851da177e4SLinus Torvalds
861da177e4SLinus Torvalds if (!eisa_eeprom_addr)
871da177e4SLinus Torvalds return -ENODEV;
881da177e4SLinus Torvalds
891da177e4SLinus Torvalds retval = misc_register(&eisa_eeprom_dev);
901da177e4SLinus Torvalds if (retval < 0) {
911da177e4SLinus Torvalds printk(KERN_ERR "EISA EEPROM: cannot register misc device.\n");
921da177e4SLinus Torvalds return retval;
931da177e4SLinus Torvalds }
941da177e4SLinus Torvalds
9528df2f83SHelge Deller printk(KERN_INFO "EISA EEPROM at 0x%px\n", eisa_eeprom_addr);
961da177e4SLinus Torvalds return 0;
971da177e4SLinus Torvalds }
981da177e4SLinus Torvalds
991da177e4SLinus Torvalds MODULE_LICENSE("GPL");
1001da177e4SLinus Torvalds
1011da177e4SLinus Torvalds module_init(eisa_eeprom_init);
102