1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * ISA Plug & Play support
4 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
5 */
6
7#include <linux/module.h>
8#include <linux/isapnp.h>
9#include <linux/proc_fs.h>
10#include <linux/init.h>
11#include <linux/uaccess.h>
12
13extern struct pnp_protocol isapnp_protocol;
14
15static struct proc_dir_entry *isapnp_proc_bus_dir = NULL;
16
17static loff_t isapnp_proc_bus_lseek(struct file *file, loff_t off, int whence)
18{
19 return fixed_size_llseek(file, offset: off, whence, size: 256);
20}
21
22static ssize_t isapnp_proc_bus_read(struct file *file, char __user * buf,
23 size_t nbytes, loff_t * ppos)
24{
25 struct pnp_dev *dev = pde_data(inode: file_inode(f: file));
26 int pos = *ppos;
27 int cnt, size = 256;
28
29 if (pos >= size)
30 return 0;
31 if (nbytes >= size)
32 nbytes = size;
33 if (pos + nbytes > size)
34 nbytes = size - pos;
35 cnt = nbytes;
36
37 if (!access_ok(buf, cnt))
38 return -EINVAL;
39
40 isapnp_cfg_begin(csn: dev->card->number, device: dev->number);
41 for (; pos < 256 && cnt > 0; pos++, buf++, cnt--) {
42 unsigned char val;
43 val = isapnp_read_byte(idx: pos);
44 __put_user(val, buf);
45 }
46 isapnp_cfg_end();
47
48 *ppos = pos;
49 return nbytes;
50}
51
52static const struct proc_ops isapnp_proc_bus_proc_ops = {
53 .proc_lseek = isapnp_proc_bus_lseek,
54 .proc_read = isapnp_proc_bus_read,
55};
56
57static int isapnp_proc_attach_device(struct pnp_dev *dev)
58{
59 struct pnp_card *bus = dev->card;
60 char name[16];
61
62 if (!bus->procdir) {
63 sprintf(buf: name, fmt: "%02x", bus->number);
64 bus->procdir = proc_mkdir(name, isapnp_proc_bus_dir);
65 if (!bus->procdir)
66 return -ENOMEM;
67 }
68 sprintf(buf: name, fmt: "%02x", dev->number);
69 dev->procent = proc_create_data(name, S_IFREG | S_IRUGO, bus->procdir,
70 &isapnp_proc_bus_proc_ops, dev);
71 if (!dev->procent)
72 return -ENOMEM;
73 proc_set_size(dev->procent, 256);
74 return 0;
75}
76
77int __init isapnp_proc_init(void)
78{
79 struct pnp_dev *dev;
80
81 isapnp_proc_bus_dir = proc_mkdir("bus/isapnp", NULL);
82 protocol_for_each_dev(&isapnp_protocol, dev) {
83 isapnp_proc_attach_device(dev);
84 }
85 return 0;
86}
87

source code of linux/drivers/pnp/isapnp/proc.c