LXR linux/drivers/pnp/isapnp/proc.c

   1/*
   2 *  ISA Plug & Play support
   3 *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
   4 *
   5 *   This program is free software; you can redistribute it and/or modify
   6 *   it under the terms of the GNU General Public License as published by
   7 *   the Free Software Foundation; either version 2 of the License, or
   8 *   (at your option) any later version.
   9 *
  10 *   This program is distributed in the hope that it will be useful,
  11 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 *   GNU General Public License for more details.
  14 *
  15 *   You should have received a copy of the GNU General Public License
  16 *   along with this program; if not, write to the Free Software
  17 *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  18 */
  19
  20#include <linux/module.h>
  21#include <linux/isapnp.h>
  22#include <linux/proc_fs.h>
  23#include <linux/init.h>
  24#include <linux/smp_lock.h>
  25#include <asm/uaccess.h>
  26
  27extern struct pnp_protocol isapnp_protocol;
  28
  29static struct proc_dir_entry *isapnp_proc_bus_dir = NULL;
  30
  31static loff_t isapnp_proc_bus_lseek(struct file *file, loff_t off, int whence)
  32{
  33        loff_t new = -1;
  34
  35        lock_kernel();
  36        switch (whence) {
  37        case 0:
  38                new = off;
  39                break;
  40        case 1:
  41                new = file->f_pos + off;
  42                break;
  43        case 2:
  44                new = 256 + off;
  45                break;
  46        }
  47        if (new < 0 || new > 256) {
  48                unlock_kernel();
  49                return -EINVAL;
  50        }
  51        unlock_kernel();
  52        return (file->f_pos = new);
  53}
  54
  55static ssize_t isapnp_proc_bus_read(struct file *file, char __user * buf,
  56                                    size_t nbytes, loff_t * ppos)
  57{
  58        struct inode *ino = file->f_path.dentry->d_inode;
  59        struct proc_dir_entry *dp = PDE(ino);
  60        struct pnp_dev *dev = dp->data;
  61        int pos = *ppos;
  62        int cnt, size = 256;
  63
  64        if (pos >= size)
  65                return 0;
  66        if (nbytes >= size)
  67                nbytes = size;
  68        if (pos + nbytes > size)
  69                nbytes = size - pos;
  70        cnt = nbytes;
  71
  72        if (!access_ok(VERIFY_WRITE, buf, cnt))
  73                return -EINVAL;
  74
  75        isapnp_cfg_begin(dev->card->number, dev->number);
  76        for (; pos < 256 && cnt > 0; pos++, buf++, cnt--) {
  77                unsigned char val;
  78                val = isapnp_read_byte(pos);
  79                __put_user(val, buf);
  80        }
  81        isapnp_cfg_end();
  82
  83        *ppos = pos;
  84        return nbytes;
  85}
  86
  87static const struct file_operations isapnp_proc_bus_file_operations = {
  88        .owner  = THIS_MODULE,
  89        .llseek = isapnp_proc_bus_lseek,
  90        .read = isapnp_proc_bus_read,
  91};
  92
  93static int isapnp_proc_attach_device(struct pnp_dev *dev)
  94{
  95        struct pnp_card *bus = dev->card;
  96        struct proc_dir_entry *de, *e;
  97        char name[16];
  98
  99        if (!(de = bus->procdir)) {
 100                sprintf(name, "%02x", bus->number);
 101                de = bus->procdir = proc_mkdir(name, isapnp_proc_bus_dir);
 102                if (!de)
 103                        return -ENOMEM;
 104        }
 105        sprintf(name, "%02x", dev->number);
 106        e = dev->procent = proc_create_data(name, S_IFREG | S_IRUGO, de,
 107                        &isapnp_proc_bus_file_operations, dev);
 108        if (!e)
 109                return -ENOMEM;
 110        e->size = 256;
 111        return 0;
 112}
 113
 114int __init isapnp_proc_init(void)
 115{
 116        struct pnp_dev *dev;
 117
 118        isapnp_proc_bus_dir = proc_mkdir("bus/isapnp", NULL);
 119        protocol_for_each_dev(&isapnp_protocol, dev) {
 120                isapnp_proc_attach_device(dev);
 121        }
 122        return 0;
 123}
 124