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, off, whence, 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(file_inode(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(dev->card->number, dev->number);
41	for (; pos < 256 && cnt > 0; pos++, buf++, cnt--) {
42		unsigned char val;
43		val = isapnp_read_byte(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(name, "%02x", bus->number);
64		bus->procdir = proc_mkdir(name, isapnp_proc_bus_dir);
65		if (!bus->procdir)
66			return -ENOMEM;
67	}
68	sprintf(name, "%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