xref: /openbmc/linux/drivers/pnp/pnpbios/proc.c (revision e3b9f1e8)
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 
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 
50 static int pnpconfig_proc_open(struct inode *inode, struct file *file)
51 {
52 	return single_open(file, pnpconfig_proc_show, NULL);
53 }
54 
55 static const struct file_operations pnpconfig_proc_fops = {
56 	.owner		= THIS_MODULE,
57 	.open		= pnpconfig_proc_open,
58 	.read		= seq_read,
59 	.llseek		= seq_lseek,
60 	.release	= single_release,
61 };
62 
63 static int escd_info_proc_show(struct seq_file *m, void *v)
64 {
65 	struct escd_info_struc escd;
66 
67 	if (pnp_bios_escd_info(&escd))
68 		return -EIO;
69 	seq_printf(m, "min_ESCD_write_size %d\n"
70 			"ESCD_size %d\n"
71 			"NVRAM_base 0x%x\n",
72 			escd.min_escd_write_size,
73 			escd.escd_size, escd.nv_storage_base);
74 	return 0;
75 }
76 
77 static int escd_info_proc_open(struct inode *inode, struct file *file)
78 {
79 	return single_open(file, escd_info_proc_show, NULL);
80 }
81 
82 static const struct file_operations escd_info_proc_fops = {
83 	.owner		= THIS_MODULE,
84 	.open		= escd_info_proc_open,
85 	.read		= seq_read,
86 	.llseek		= seq_lseek,
87 	.release	= single_release,
88 };
89 
90 #define MAX_SANE_ESCD_SIZE (32*1024)
91 static int escd_proc_show(struct seq_file *m, void *v)
92 {
93 	struct escd_info_struc escd;
94 	char *tmpbuf;
95 	int escd_size;
96 
97 	if (pnp_bios_escd_info(&escd))
98 		return -EIO;
99 
100 	/* sanity check */
101 	if (escd.escd_size > MAX_SANE_ESCD_SIZE) {
102 		printk(KERN_ERR
103 		       "PnPBIOS: %s: ESCD size reported by BIOS escd_info call is too great\n", __func__);
104 		return -EFBIG;
105 	}
106 
107 	tmpbuf = kzalloc(escd.escd_size, GFP_KERNEL);
108 	if (!tmpbuf)
109 		return -ENOMEM;
110 
111 	if (pnp_bios_read_escd(tmpbuf, escd.nv_storage_base)) {
112 		kfree(tmpbuf);
113 		return -EIO;
114 	}
115 
116 	escd_size =
117 	    (unsigned char)(tmpbuf[0]) + (unsigned char)(tmpbuf[1]) * 256;
118 
119 	/* sanity check */
120 	if (escd_size > MAX_SANE_ESCD_SIZE) {
121 		printk(KERN_ERR "PnPBIOS: %s: ESCD size reported by"
122 				" BIOS read_escd call is too great\n", __func__);
123 		kfree(tmpbuf);
124 		return -EFBIG;
125 	}
126 
127 	seq_write(m, tmpbuf, escd_size);
128 	kfree(tmpbuf);
129 	return 0;
130 }
131 
132 static int escd_proc_open(struct inode *inode, struct file *file)
133 {
134 	return single_open(file, escd_proc_show, NULL);
135 }
136 
137 static const struct file_operations escd_proc_fops = {
138 	.owner		= THIS_MODULE,
139 	.open		= escd_proc_open,
140 	.read		= seq_read,
141 	.llseek		= seq_lseek,
142 	.release	= single_release,
143 };
144 
145 static int pnp_legacyres_proc_show(struct seq_file *m, void *v)
146 {
147 	void *buf;
148 
149 	buf = kmalloc(65536, GFP_KERNEL);
150 	if (!buf)
151 		return -ENOMEM;
152 	if (pnp_bios_get_stat_res(buf)) {
153 		kfree(buf);
154 		return -EIO;
155 	}
156 
157 	seq_write(m, buf, 65536);
158 	kfree(buf);
159 	return 0;
160 }
161 
162 static int pnp_legacyres_proc_open(struct inode *inode, struct file *file)
163 {
164 	return single_open(file, pnp_legacyres_proc_show, NULL);
165 }
166 
167 static const struct file_operations pnp_legacyres_proc_fops = {
168 	.owner		= THIS_MODULE,
169 	.open		= pnp_legacyres_proc_open,
170 	.read		= seq_read,
171 	.llseek		= seq_lseek,
172 	.release	= single_release,
173 };
174 
175 static int pnp_devices_proc_show(struct seq_file *m, void *v)
176 {
177 	struct pnp_bios_node *node;
178 	u8 nodenum;
179 
180 	node = kzalloc(node_info.max_node_size, GFP_KERNEL);
181 	if (!node)
182 		return -ENOMEM;
183 
184 	for (nodenum = 0; nodenum < 0xff;) {
185 		u8 thisnodenum = nodenum;
186 
187 		if (pnp_bios_get_dev_node(&nodenum, PNPMODE_DYNAMIC, node))
188 			break;
189 		seq_printf(m, "%02x\t%08x\t%3phC\t%04x\n",
190 			     node->handle, node->eisa_id,
191 			     node->type_code, node->flags);
192 		if (nodenum <= thisnodenum) {
193 			printk(KERN_ERR
194 			       "%s Node number 0x%x is out of sequence following node 0x%x. Aborting.\n",
195 			       "PnPBIOS: proc_read_devices:",
196 			       (unsigned int)nodenum,
197 			       (unsigned int)thisnodenum);
198 			break;
199 		}
200 	}
201 	kfree(node);
202 	return 0;
203 }
204 
205 static int pnp_devices_proc_open(struct inode *inode, struct file *file)
206 {
207 	return single_open(file, pnp_devices_proc_show, NULL);
208 }
209 
210 static const struct file_operations pnp_devices_proc_fops = {
211 	.owner		= THIS_MODULE,
212 	.open		= pnp_devices_proc_open,
213 	.read		= seq_read,
214 	.llseek		= seq_lseek,
215 	.release	= single_release,
216 };
217 
218 static int pnpbios_proc_show(struct seq_file *m, void *v)
219 {
220 	void *data = m->private;
221 	struct pnp_bios_node *node;
222 	int boot = (long)data >> 8;
223 	u8 nodenum = (long)data;
224 	int len;
225 
226 	node = kzalloc(node_info.max_node_size, GFP_KERNEL);
227 	if (!node)
228 		return -ENOMEM;
229 	if (pnp_bios_get_dev_node(&nodenum, boot, node)) {
230 		kfree(node);
231 		return -EIO;
232 	}
233 	len = node->size - sizeof(struct pnp_bios_node);
234 	seq_write(m, node->data, len);
235 	kfree(node);
236 	return 0;
237 }
238 
239 static int pnpbios_proc_open(struct inode *inode, struct file *file)
240 {
241 	return single_open(file, pnpbios_proc_show, PDE_DATA(inode));
242 }
243 
244 static ssize_t pnpbios_proc_write(struct file *file, const char __user *buf,
245 				  size_t count, loff_t *pos)
246 {
247 	void *data = PDE_DATA(file_inode(file));
248 	struct pnp_bios_node *node;
249 	int boot = (long)data >> 8;
250 	u8 nodenum = (long)data;
251 	int ret = count;
252 
253 	node = kzalloc(node_info.max_node_size, GFP_KERNEL);
254 	if (!node)
255 		return -ENOMEM;
256 	if (pnp_bios_get_dev_node(&nodenum, boot, node)) {
257 		ret = -EIO;
258 		goto out;
259 	}
260 	if (count != node->size - sizeof(struct pnp_bios_node)) {
261 		ret = -EINVAL;
262 		goto out;
263 	}
264 	if (copy_from_user(node->data, buf, count)) {
265 		ret = -EFAULT;
266 		goto out;
267 	}
268 	if (pnp_bios_set_dev_node(node->handle, boot, node) != 0) {
269 		ret = -EINVAL;
270 		goto out;
271 	}
272 	ret = count;
273 out:
274 	kfree(node);
275 	return ret;
276 }
277 
278 static const struct file_operations pnpbios_proc_fops = {
279 	.owner		= THIS_MODULE,
280 	.open		= pnpbios_proc_open,
281 	.read		= seq_read,
282 	.llseek		= seq_lseek,
283 	.release	= single_release,
284 	.write		= pnpbios_proc_write,
285 };
286 
287 int pnpbios_interface_attach_device(struct pnp_bios_node *node)
288 {
289 	char name[3];
290 
291 	sprintf(name, "%02x", node->handle);
292 
293 	if (!proc_pnp)
294 		return -EIO;
295 	if (!pnpbios_dont_use_current_config) {
296 		proc_create_data(name, 0644, proc_pnp, &pnpbios_proc_fops,
297 				 (void *)(long)(node->handle));
298 	}
299 
300 	if (!proc_pnp_boot)
301 		return -EIO;
302 	if (proc_create_data(name, 0644, proc_pnp_boot, &pnpbios_proc_fops,
303 			     (void *)(long)(node->handle + 0x100)))
304 		return 0;
305 	return -EIO;
306 }
307 
308 /*
309  * When this is called, pnpbios functions are assumed to
310  * work and the pnpbios_dont_use_current_config flag
311  * should already have been set to the appropriate value
312  */
313 int __init pnpbios_proc_init(void)
314 {
315 	proc_pnp = proc_mkdir("bus/pnp", NULL);
316 	if (!proc_pnp)
317 		return -EIO;
318 	proc_pnp_boot = proc_mkdir("boot", proc_pnp);
319 	if (!proc_pnp_boot)
320 		return -EIO;
321 	proc_create("devices", 0, proc_pnp, &pnp_devices_proc_fops);
322 	proc_create("configuration_info", 0, proc_pnp, &pnpconfig_proc_fops);
323 	proc_create("escd_info", 0, proc_pnp, &escd_info_proc_fops);
324 	proc_create("escd", S_IRUSR, proc_pnp, &escd_proc_fops);
325 	proc_create("legacy_device_resources", 0, proc_pnp, &pnp_legacyres_proc_fops);
326 
327 	return 0;
328 }
329 
330 void __exit pnpbios_proc_exit(void)
331 {
332 	int i;
333 	char name[3];
334 
335 	if (!proc_pnp)
336 		return;
337 
338 	for (i = 0; i < 0xff; i++) {
339 		sprintf(name, "%02x", i);
340 		if (!pnpbios_dont_use_current_config)
341 			remove_proc_entry(name, proc_pnp);
342 		remove_proc_entry(name, proc_pnp_boot);
343 	}
344 	remove_proc_entry("legacy_device_resources", proc_pnp);
345 	remove_proc_entry("escd", proc_pnp);
346 	remove_proc_entry("escd_info", proc_pnp);
347 	remove_proc_entry("configuration_info", proc_pnp);
348 	remove_proc_entry("devices", proc_pnp);
349 	remove_proc_entry("boot", proc_pnp);
350 	remove_proc_entry("bus/pnp", NULL);
351 }
352