1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * /proc/bus/pnp interface for Plug and Play devices
4 *
5 * Written by David Hinds, dahinds@users.sourceforge.net
6 * Modified by Thomas Hood
7 *
8 * The .../devices and .../<node> and .../boot/<node> files are
9 * utilized by the lspnp and setpnp utilities, supplied with the
10 * pcmcia-cs package.
11 * http://pcmcia-cs.sourceforge.net
12 *
13 * The .../escd file is utilized by the lsescd utility written by
14 * Gunther Mayer.
15 *
16 * The .../legacy_device_resources file is not used yet.
17 *
18 * The other files are human-readable.
19 */
20
21 #include <linux/module.h>
22 #include <linux/kernel.h>
23 #include <linux/slab.h>
24 #include <linux/types.h>
25 #include <linux/proc_fs.h>
26 #include <linux/pnp.h>
27 #include <linux/seq_file.h>
28 #include <linux/init.h>
29
30 #include <linux/uaccess.h>
31
32 #include "pnpbios.h"
33
34 static struct proc_dir_entry *proc_pnp = NULL;
35 static struct proc_dir_entry *proc_pnp_boot = NULL;
36
pnpconfig_proc_show(struct seq_file * m,void * v)37 static int pnpconfig_proc_show(struct seq_file *m, void *v)
38 {
39 struct pnp_isa_config_struc pnps;
40
41 if (pnp_bios_isapnp_config(&pnps))
42 return -EIO;
43 seq_printf(m, "structure_revision %d\n"
44 "number_of_CSNs %d\n"
45 "ISA_read_data_port 0x%x\n",
46 pnps.revision, pnps.no_csns, pnps.isa_rd_data_port);
47 return 0;
48 }
49
escd_info_proc_show(struct seq_file * m,void * v)50 static int escd_info_proc_show(struct seq_file *m, void *v)
51 {
52 struct escd_info_struc escd;
53
54 if (pnp_bios_escd_info(&escd))
55 return -EIO;
56 seq_printf(m, "min_ESCD_write_size %d\n"
57 "ESCD_size %d\n"
58 "NVRAM_base 0x%x\n",
59 escd.min_escd_write_size,
60 escd.escd_size, escd.nv_storage_base);
61 return 0;
62 }
63
64 #define MAX_SANE_ESCD_SIZE (32*1024)
escd_proc_show(struct seq_file * m,void * v)65 static int escd_proc_show(struct seq_file *m, void *v)
66 {
67 struct escd_info_struc escd;
68 char *tmpbuf;
69 int escd_size;
70
71 if (pnp_bios_escd_info(&escd))
72 return -EIO;
73
74 /* sanity check */
75 if (escd.escd_size > MAX_SANE_ESCD_SIZE) {
76 printk(KERN_ERR
77 "PnPBIOS: %s: ESCD size reported by BIOS escd_info call is too great\n", __func__);
78 return -EFBIG;
79 }
80
81 tmpbuf = kzalloc(escd.escd_size, GFP_KERNEL);
82 if (!tmpbuf)
83 return -ENOMEM;
84
85 if (pnp_bios_read_escd(tmpbuf, escd.nv_storage_base)) {
86 kfree(tmpbuf);
87 return -EIO;
88 }
89
90 escd_size =
91 (unsigned char)(tmpbuf[0]) + (unsigned char)(tmpbuf[1]) * 256;
92
93 /* sanity check */
94 if (escd_size > MAX_SANE_ESCD_SIZE) {
95 printk(KERN_ERR "PnPBIOS: %s: ESCD size reported by"
96 " BIOS read_escd call is too great\n", __func__);
97 kfree(tmpbuf);
98 return -EFBIG;
99 }
100
101 seq_write(m, tmpbuf, escd_size);
102 kfree(tmpbuf);
103 return 0;
104 }
105
pnp_legacyres_proc_show(struct seq_file * m,void * v)106 static int pnp_legacyres_proc_show(struct seq_file *m, void *v)
107 {
108 void *buf;
109
110 buf = kmalloc(65536, GFP_KERNEL);
111 if (!buf)
112 return -ENOMEM;
113 if (pnp_bios_get_stat_res(buf)) {
114 kfree(buf);
115 return -EIO;
116 }
117
118 seq_write(m, buf, 65536);
119 kfree(buf);
120 return 0;
121 }
122
pnp_devices_proc_show(struct seq_file * m,void * v)123 static int pnp_devices_proc_show(struct seq_file *m, void *v)
124 {
125 struct pnp_bios_node *node;
126 u8 nodenum;
127
128 node = kzalloc(node_info.max_node_size, GFP_KERNEL);
129 if (!node)
130 return -ENOMEM;
131
132 for (nodenum = 0; nodenum < 0xff;) {
133 u8 thisnodenum = nodenum;
134
135 if (pnp_bios_get_dev_node(&nodenum, PNPMODE_DYNAMIC, node))
136 break;
137 seq_printf(m, "%02x\t%08x\t%3phC\t%04x\n",
138 node->handle, node->eisa_id,
139 node->type_code, node->flags);
140 if (nodenum <= thisnodenum) {
141 printk(KERN_ERR
142 "%s Node number 0x%x is out of sequence following node 0x%x. Aborting.\n",
143 "PnPBIOS: proc_read_devices:",
144 (unsigned int)nodenum,
145 (unsigned int)thisnodenum);
146 break;
147 }
148 }
149 kfree(node);
150 return 0;
151 }
152
pnpbios_proc_show(struct seq_file * m,void * v)153 static int pnpbios_proc_show(struct seq_file *m, void *v)
154 {
155 void *data = m->private;
156 struct pnp_bios_node *node;
157 int boot = (long)data >> 8;
158 u8 nodenum = (long)data;
159 int len;
160
161 node = kzalloc(node_info.max_node_size, GFP_KERNEL);
162 if (!node)
163 return -ENOMEM;
164 if (pnp_bios_get_dev_node(&nodenum, boot, node)) {
165 kfree(node);
166 return -EIO;
167 }
168 len = node->size - sizeof(struct pnp_bios_node);
169 seq_write(m, node->data, len);
170 kfree(node);
171 return 0;
172 }
173
pnpbios_proc_open(struct inode * inode,struct file * file)174 static int pnpbios_proc_open(struct inode *inode, struct file *file)
175 {
176 return single_open(file, pnpbios_proc_show, pde_data(inode));
177 }
178
pnpbios_proc_write(struct file * file,const char __user * buf,size_t count,loff_t * pos)179 static ssize_t pnpbios_proc_write(struct file *file, const char __user *buf,
180 size_t count, loff_t *pos)
181 {
182 void *data = pde_data(file_inode(file));
183 struct pnp_bios_node *node;
184 int boot = (long)data >> 8;
185 u8 nodenum = (long)data;
186 int ret = count;
187
188 node = kzalloc(node_info.max_node_size, GFP_KERNEL);
189 if (!node)
190 return -ENOMEM;
191 if (pnp_bios_get_dev_node(&nodenum, boot, node)) {
192 ret = -EIO;
193 goto out;
194 }
195 if (count != node->size - sizeof(struct pnp_bios_node)) {
196 ret = -EINVAL;
197 goto out;
198 }
199 if (copy_from_user(node->data, buf, count)) {
200 ret = -EFAULT;
201 goto out;
202 }
203 if (pnp_bios_set_dev_node(node->handle, boot, node) != 0) {
204 ret = -EINVAL;
205 goto out;
206 }
207 ret = count;
208 out:
209 kfree(node);
210 return ret;
211 }
212
213 static const struct proc_ops pnpbios_proc_ops = {
214 .proc_open = pnpbios_proc_open,
215 .proc_read = seq_read,
216 .proc_lseek = seq_lseek,
217 .proc_release = single_release,
218 .proc_write = pnpbios_proc_write,
219 };
220
pnpbios_interface_attach_device(struct pnp_bios_node * node)221 int pnpbios_interface_attach_device(struct pnp_bios_node *node)
222 {
223 char name[3];
224
225 sprintf(name, "%02x", node->handle);
226
227 if (!proc_pnp)
228 return -EIO;
229 if (!pnpbios_dont_use_current_config) {
230 proc_create_data(name, 0644, proc_pnp, &pnpbios_proc_ops,
231 (void *)(long)(node->handle));
232 }
233
234 if (!proc_pnp_boot)
235 return -EIO;
236 if (proc_create_data(name, 0644, proc_pnp_boot, &pnpbios_proc_ops,
237 (void *)(long)(node->handle + 0x100)))
238 return 0;
239 return -EIO;
240 }
241
242 /*
243 * When this is called, pnpbios functions are assumed to
244 * work and the pnpbios_dont_use_current_config flag
245 * should already have been set to the appropriate value
246 */
pnpbios_proc_init(void)247 int __init pnpbios_proc_init(void)
248 {
249 proc_pnp = proc_mkdir("bus/pnp", NULL);
250 if (!proc_pnp)
251 return -EIO;
252 proc_pnp_boot = proc_mkdir("boot", proc_pnp);
253 if (!proc_pnp_boot)
254 return -EIO;
255 proc_create_single("devices", 0, proc_pnp, pnp_devices_proc_show);
256 proc_create_single("configuration_info", 0, proc_pnp,
257 pnpconfig_proc_show);
258 proc_create_single("escd_info", 0, proc_pnp, escd_info_proc_show);
259 proc_create_single("escd", S_IRUSR, proc_pnp, escd_proc_show);
260 proc_create_single("legacy_device_resources", 0, proc_pnp,
261 pnp_legacyres_proc_show);
262 return 0;
263 }
264
pnpbios_proc_exit(void)265 void __exit pnpbios_proc_exit(void)
266 {
267 int i;
268 char name[3];
269
270 if (!proc_pnp)
271 return;
272
273 for (i = 0; i < 0xff; i++) {
274 sprintf(name, "%02x", i);
275 if (!pnpbios_dont_use_current_config)
276 remove_proc_entry(name, proc_pnp);
277 remove_proc_entry(name, proc_pnp_boot);
278 }
279 remove_proc_entry("legacy_device_resources", proc_pnp);
280 remove_proc_entry("escd", proc_pnp);
281 remove_proc_entry("escd_info", proc_pnp);
282 remove_proc_entry("configuration_info", proc_pnp);
283 remove_proc_entry("devices", proc_pnp);
284 remove_proc_entry("boot", proc_pnp);
285 remove_proc_entry("bus/pnp", NULL);
286 }
287