1 /*
2 * Common functions for kernel modules using Dell SMBIOS
3 *
4 * Copyright (c) Red Hat <mjg@redhat.com>
5 * Copyright (c) 2014 Gabriele Mazzotta <gabriele.mzt@gmail.com>
6 * Copyright (c) 2014 Pali Rohár <pali.rohar@gmail.com>
7 *
8 * Based on documentation in the libsmbios package:
9 * Copyright (C) 2005-2014 Dell Inc.
10 *
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License version 2 as
13 * published by the Free Software Foundation.
14 */
15 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
16
17 #include <linux/kernel.h>
18 #include <linux/module.h>
19 #include <linux/capability.h>
20 #include <linux/dmi.h>
21 #include <linux/err.h>
22 #include <linux/mutex.h>
23 #include <linux/platform_device.h>
24 #include <linux/slab.h>
25 #include "dell-smbios.h"
26
27 static u32 da_supported_commands;
28 static int da_num_tokens;
29 static struct platform_device *platform_device;
30 static struct calling_interface_token *da_tokens;
31 static struct device_attribute *token_location_attrs;
32 static struct device_attribute *token_value_attrs;
33 static struct attribute **token_attrs;
34 static DEFINE_MUTEX(smbios_mutex);
35
36 struct smbios_device {
37 struct list_head list;
38 struct device *device;
39 int (*call_fn)(struct calling_interface_buffer *arg);
40 };
41
42 struct smbios_call {
43 u32 need_capability;
44 int cmd_class;
45 int cmd_select;
46 };
47
48 /* calls that are whitelisted for given capabilities */
49 static struct smbios_call call_whitelist[] = {
50 /* generally tokens are allowed, but may be further filtered or
51 * restricted by token blacklist or whitelist
52 */
53 {CAP_SYS_ADMIN, CLASS_TOKEN_READ, SELECT_TOKEN_STD},
54 {CAP_SYS_ADMIN, CLASS_TOKEN_READ, SELECT_TOKEN_AC},
55 {CAP_SYS_ADMIN, CLASS_TOKEN_READ, SELECT_TOKEN_BAT},
56 {CAP_SYS_ADMIN, CLASS_TOKEN_WRITE, SELECT_TOKEN_STD},
57 {CAP_SYS_ADMIN, CLASS_TOKEN_WRITE, SELECT_TOKEN_AC},
58 {CAP_SYS_ADMIN, CLASS_TOKEN_WRITE, SELECT_TOKEN_BAT},
59 /* used by userspace: fwupdate */
60 {CAP_SYS_ADMIN, CLASS_ADMIN_PROP, SELECT_ADMIN_PROP},
61 /* used by userspace: fwupd */
62 {CAP_SYS_ADMIN, CLASS_INFO, SELECT_DOCK},
63 {CAP_SYS_ADMIN, CLASS_FLASH_INTERFACE, SELECT_FLASH_INTERFACE},
64 };
65
66 /* calls that are explicitly blacklisted */
67 static struct smbios_call call_blacklist[] = {
68 {0x0000, 1, 7}, /* manufacturing use */
69 {0x0000, 6, 5}, /* manufacturing use */
70 {0x0000, 11, 3}, /* write once */
71 {0x0000, 11, 7}, /* write once */
72 {0x0000, 11, 11}, /* write once */
73 {0x0000, 19, -1}, /* diagnostics */
74 /* handled by kernel: dell-laptop */
75 {0x0000, CLASS_INFO, SELECT_RFKILL},
76 {0x0000, CLASS_KBD_BACKLIGHT, SELECT_KBD_BACKLIGHT},
77 };
78
79 struct token_range {
80 u32 need_capability;
81 u16 min;
82 u16 max;
83 };
84
85 /* tokens that are whitelisted for given capabilities */
86 static struct token_range token_whitelist[] = {
87 /* used by userspace: fwupdate */
88 {CAP_SYS_ADMIN, CAPSULE_EN_TOKEN, CAPSULE_DIS_TOKEN},
89 /* can indicate to userspace that WMI is needed */
90 {0x0000, WSMT_EN_TOKEN, WSMT_DIS_TOKEN}
91 };
92
93 /* tokens that are explicitly blacklisted */
94 static struct token_range token_blacklist[] = {
95 {0x0000, 0x0058, 0x0059}, /* ME use */
96 {0x0000, 0x00CD, 0x00D0}, /* raid shadow copy */
97 {0x0000, 0x013A, 0x01FF}, /* sata shadow copy */
98 {0x0000, 0x0175, 0x0176}, /* write once */
99 {0x0000, 0x0195, 0x0197}, /* diagnostics */
100 {0x0000, 0x01DC, 0x01DD}, /* manufacturing use */
101 {0x0000, 0x027D, 0x0284}, /* diagnostics */
102 {0x0000, 0x02E3, 0x02E3}, /* manufacturing use */
103 {0x0000, 0x02FF, 0x02FF}, /* manufacturing use */
104 {0x0000, 0x0300, 0x0302}, /* manufacturing use */
105 {0x0000, 0x0325, 0x0326}, /* manufacturing use */
106 {0x0000, 0x0332, 0x0335}, /* fan control */
107 {0x0000, 0x0350, 0x0350}, /* manufacturing use */
108 {0x0000, 0x0363, 0x0363}, /* manufacturing use */
109 {0x0000, 0x0368, 0x0368}, /* manufacturing use */
110 {0x0000, 0x03F6, 0x03F7}, /* manufacturing use */
111 {0x0000, 0x049E, 0x049F}, /* manufacturing use */
112 {0x0000, 0x04A0, 0x04A3}, /* disagnostics */
113 {0x0000, 0x04E6, 0x04E7}, /* manufacturing use */
114 {0x0000, 0x4000, 0x7FFF}, /* internal BIOS use */
115 {0x0000, 0x9000, 0x9001}, /* internal BIOS use */
116 {0x0000, 0xA000, 0xBFFF}, /* write only */
117 {0x0000, 0xEFF0, 0xEFFF}, /* internal BIOS use */
118 /* handled by kernel: dell-laptop */
119 {0x0000, BRIGHTNESS_TOKEN, BRIGHTNESS_TOKEN},
120 {0x0000, KBD_LED_OFF_TOKEN, KBD_LED_AUTO_TOKEN},
121 {0x0000, KBD_LED_AC_TOKEN, KBD_LED_AC_TOKEN},
122 {0x0000, KBD_LED_AUTO_25_TOKEN, KBD_LED_AUTO_75_TOKEN},
123 {0x0000, KBD_LED_AUTO_100_TOKEN, KBD_LED_AUTO_100_TOKEN},
124 {0x0000, GLOBAL_MIC_MUTE_ENABLE, GLOBAL_MIC_MUTE_DISABLE},
125 };
126
127 static LIST_HEAD(smbios_device_list);
128
dell_smbios_error(int value)129 int dell_smbios_error(int value)
130 {
131 switch (value) {
132 case 0: /* Completed successfully */
133 return 0;
134 case -1: /* Completed with error */
135 return -EIO;
136 case -2: /* Function not supported */
137 return -ENXIO;
138 default: /* Unknown error */
139 return -EINVAL;
140 }
141 }
142 EXPORT_SYMBOL_GPL(dell_smbios_error);
143
dell_smbios_register_device(struct device * d,void * call_fn)144 int dell_smbios_register_device(struct device *d, void *call_fn)
145 {
146 struct smbios_device *priv;
147
148 priv = devm_kzalloc(d, sizeof(struct smbios_device), GFP_KERNEL);
149 if (!priv)
150 return -ENOMEM;
151 get_device(d);
152 priv->device = d;
153 priv->call_fn = call_fn;
154 mutex_lock(&smbios_mutex);
155 list_add_tail(&priv->list, &smbios_device_list);
156 mutex_unlock(&smbios_mutex);
157 dev_dbg(d, "Added device: %s\n", d->driver->name);
158 return 0;
159 }
160 EXPORT_SYMBOL_GPL(dell_smbios_register_device);
161
dell_smbios_unregister_device(struct device * d)162 void dell_smbios_unregister_device(struct device *d)
163 {
164 struct smbios_device *priv;
165
166 mutex_lock(&smbios_mutex);
167 list_for_each_entry(priv, &smbios_device_list, list) {
168 if (priv->device == d) {
169 list_del(&priv->list);
170 put_device(d);
171 break;
172 }
173 }
174 mutex_unlock(&smbios_mutex);
175 dev_dbg(d, "Remove device: %s\n", d->driver->name);
176 }
177 EXPORT_SYMBOL_GPL(dell_smbios_unregister_device);
178
dell_smbios_call_filter(struct device * d,struct calling_interface_buffer * buffer)179 int dell_smbios_call_filter(struct device *d,
180 struct calling_interface_buffer *buffer)
181 {
182 u16 t = 0;
183 int i;
184
185 /* can't make calls over 30 */
186 if (buffer->cmd_class > 30) {
187 dev_dbg(d, "class too big: %u\n", buffer->cmd_class);
188 return -EINVAL;
189 }
190
191 /* supported calls on the particular system */
192 if (!(da_supported_commands & (1 << buffer->cmd_class))) {
193 dev_dbg(d, "invalid command, supported commands: 0x%8x\n",
194 da_supported_commands);
195 return -EINVAL;
196 }
197
198 /* match against call blacklist */
199 for (i = 0; i < ARRAY_SIZE(call_blacklist); i++) {
200 if (buffer->cmd_class != call_blacklist[i].cmd_class)
201 continue;
202 if (buffer->cmd_select != call_blacklist[i].cmd_select &&
203 call_blacklist[i].cmd_select != -1)
204 continue;
205 dev_dbg(d, "blacklisted command: %u/%u\n",
206 buffer->cmd_class, buffer->cmd_select);
207 return -EINVAL;
208 }
209
210 /* if a token call, find token ID */
211
212 if ((buffer->cmd_class == CLASS_TOKEN_READ ||
213 buffer->cmd_class == CLASS_TOKEN_WRITE) &&
214 buffer->cmd_select < 3) {
215 /* tokens enabled ? */
216 if (!da_tokens) {
217 dev_dbg(d, "no token support on this system\n");
218 return -EINVAL;
219 }
220
221 /* find the matching token ID */
222 for (i = 0; i < da_num_tokens; i++) {
223 if (da_tokens[i].location != buffer->input[0])
224 continue;
225 t = da_tokens[i].tokenID;
226 break;
227 }
228
229 /* token call; but token didn't exist */
230 if (!t) {
231 dev_dbg(d, "token at location %04x doesn't exist\n",
232 buffer->input[0]);
233 return -EINVAL;
234 }
235
236 /* match against token blacklist */
237 for (i = 0; i < ARRAY_SIZE(token_blacklist); i++) {
238 if (!token_blacklist[i].min || !token_blacklist[i].max)
239 continue;
240 if (t >= token_blacklist[i].min &&
241 t <= token_blacklist[i].max)
242 return -EINVAL;
243 }
244
245 /* match against token whitelist */
246 for (i = 0; i < ARRAY_SIZE(token_whitelist); i++) {
247 if (!token_whitelist[i].min || !token_whitelist[i].max)
248 continue;
249 if (t < token_whitelist[i].min ||
250 t > token_whitelist[i].max)
251 continue;
252 if (!token_whitelist[i].need_capability ||
253 capable(token_whitelist[i].need_capability)) {
254 dev_dbg(d, "whitelisted token: %x\n", t);
255 return 0;
256 }
257
258 }
259 }
260 /* match against call whitelist */
261 for (i = 0; i < ARRAY_SIZE(call_whitelist); i++) {
262 if (buffer->cmd_class != call_whitelist[i].cmd_class)
263 continue;
264 if (buffer->cmd_select != call_whitelist[i].cmd_select)
265 continue;
266 if (!call_whitelist[i].need_capability ||
267 capable(call_whitelist[i].need_capability)) {
268 dev_dbg(d, "whitelisted capable command: %u/%u\n",
269 buffer->cmd_class, buffer->cmd_select);
270 return 0;
271 }
272 dev_dbg(d, "missing capability %d for %u/%u\n",
273 call_whitelist[i].need_capability,
274 buffer->cmd_class, buffer->cmd_select);
275
276 }
277
278 /* not in a whitelist, only allow processes with capabilities */
279 if (capable(CAP_SYS_RAWIO)) {
280 dev_dbg(d, "Allowing %u/%u due to CAP_SYS_RAWIO\n",
281 buffer->cmd_class, buffer->cmd_select);
282 return 0;
283 }
284
285 return -EACCES;
286 }
287 EXPORT_SYMBOL_GPL(dell_smbios_call_filter);
288
dell_smbios_call(struct calling_interface_buffer * buffer)289 int dell_smbios_call(struct calling_interface_buffer *buffer)
290 {
291 int (*call_fn)(struct calling_interface_buffer *) = NULL;
292 struct device *selected_dev = NULL;
293 struct smbios_device *priv;
294 int ret;
295
296 mutex_lock(&smbios_mutex);
297 list_for_each_entry(priv, &smbios_device_list, list) {
298 if (!selected_dev || priv->device->id >= selected_dev->id) {
299 dev_dbg(priv->device, "Trying device ID: %d\n",
300 priv->device->id);
301 call_fn = priv->call_fn;
302 selected_dev = priv->device;
303 }
304 }
305
306 if (!selected_dev) {
307 ret = -ENODEV;
308 pr_err("No dell-smbios drivers are loaded\n");
309 goto out_smbios_call;
310 }
311
312 ret = call_fn(buffer);
313
314 out_smbios_call:
315 mutex_unlock(&smbios_mutex);
316 return ret;
317 }
318 EXPORT_SYMBOL_GPL(dell_smbios_call);
319
dell_smbios_find_token(int tokenid)320 struct calling_interface_token *dell_smbios_find_token(int tokenid)
321 {
322 int i;
323
324 if (!da_tokens)
325 return NULL;
326
327 for (i = 0; i < da_num_tokens; i++) {
328 if (da_tokens[i].tokenID == tokenid)
329 return &da_tokens[i];
330 }
331
332 return NULL;
333 }
334 EXPORT_SYMBOL_GPL(dell_smbios_find_token);
335
336 static BLOCKING_NOTIFIER_HEAD(dell_laptop_chain_head);
337
dell_laptop_register_notifier(struct notifier_block * nb)338 int dell_laptop_register_notifier(struct notifier_block *nb)
339 {
340 return blocking_notifier_chain_register(&dell_laptop_chain_head, nb);
341 }
342 EXPORT_SYMBOL_GPL(dell_laptop_register_notifier);
343
dell_laptop_unregister_notifier(struct notifier_block * nb)344 int dell_laptop_unregister_notifier(struct notifier_block *nb)
345 {
346 return blocking_notifier_chain_unregister(&dell_laptop_chain_head, nb);
347 }
348 EXPORT_SYMBOL_GPL(dell_laptop_unregister_notifier);
349
dell_laptop_call_notifier(unsigned long action,void * data)350 void dell_laptop_call_notifier(unsigned long action, void *data)
351 {
352 blocking_notifier_call_chain(&dell_laptop_chain_head, action, data);
353 }
354 EXPORT_SYMBOL_GPL(dell_laptop_call_notifier);
355
parse_da_table(const struct dmi_header * dm)356 static void __init parse_da_table(const struct dmi_header *dm)
357 {
358 /* Final token is a terminator, so we don't want to copy it */
359 int tokens = (dm->length-11)/sizeof(struct calling_interface_token)-1;
360 struct calling_interface_token *new_da_tokens;
361 struct calling_interface_structure *table =
362 container_of(dm, struct calling_interface_structure, header);
363
364 /*
365 * 4 bytes of table header, plus 7 bytes of Dell header
366 * plus at least 6 bytes of entry
367 */
368
369 if (dm->length < 17)
370 return;
371
372 da_supported_commands = table->supportedCmds;
373
374 new_da_tokens = krealloc(da_tokens, (da_num_tokens + tokens) *
375 sizeof(struct calling_interface_token),
376 GFP_KERNEL);
377
378 if (!new_da_tokens)
379 return;
380 da_tokens = new_da_tokens;
381
382 memcpy(da_tokens+da_num_tokens, table->tokens,
383 sizeof(struct calling_interface_token) * tokens);
384
385 da_num_tokens += tokens;
386 }
387
zero_duplicates(struct device * dev)388 static void zero_duplicates(struct device *dev)
389 {
390 int i, j;
391
392 for (i = 0; i < da_num_tokens; i++) {
393 if (da_tokens[i].tokenID == 0)
394 continue;
395 for (j = i+1; j < da_num_tokens; j++) {
396 if (da_tokens[j].tokenID == 0)
397 continue;
398 if (da_tokens[i].tokenID == da_tokens[j].tokenID) {
399 dev_dbg(dev, "Zeroing dup token ID %x(%x/%x)\n",
400 da_tokens[j].tokenID,
401 da_tokens[j].location,
402 da_tokens[j].value);
403 da_tokens[j].tokenID = 0;
404 }
405 }
406 }
407 }
408
find_tokens(const struct dmi_header * dm,void * dummy)409 static void __init find_tokens(const struct dmi_header *dm, void *dummy)
410 {
411 switch (dm->type) {
412 case 0xd4: /* Indexed IO */
413 case 0xd5: /* Protected Area Type 1 */
414 case 0xd6: /* Protected Area Type 2 */
415 break;
416 case 0xda: /* Calling interface */
417 parse_da_table(dm);
418 break;
419 }
420 }
421
match_attribute(struct device * dev,struct device_attribute * attr)422 static int match_attribute(struct device *dev,
423 struct device_attribute *attr)
424 {
425 int i;
426
427 for (i = 0; i < da_num_tokens * 2; i++) {
428 if (!token_attrs[i])
429 continue;
430 if (strcmp(token_attrs[i]->name, attr->attr.name) == 0)
431 return i/2;
432 }
433 dev_dbg(dev, "couldn't match: %s\n", attr->attr.name);
434 return -EINVAL;
435 }
436
location_show(struct device * dev,struct device_attribute * attr,char * buf)437 static ssize_t location_show(struct device *dev,
438 struct device_attribute *attr, char *buf)
439 {
440 int i;
441
442 if (!capable(CAP_SYS_ADMIN))
443 return -EPERM;
444
445 i = match_attribute(dev, attr);
446 if (i > 0)
447 return scnprintf(buf, PAGE_SIZE, "%08x", da_tokens[i].location);
448 return 0;
449 }
450
value_show(struct device * dev,struct device_attribute * attr,char * buf)451 static ssize_t value_show(struct device *dev,
452 struct device_attribute *attr, char *buf)
453 {
454 int i;
455
456 if (!capable(CAP_SYS_ADMIN))
457 return -EPERM;
458
459 i = match_attribute(dev, attr);
460 if (i > 0)
461 return scnprintf(buf, PAGE_SIZE, "%08x", da_tokens[i].value);
462 return 0;
463 }
464
465 static struct attribute_group smbios_attribute_group = {
466 .name = "tokens"
467 };
468
469 static struct platform_driver platform_driver = {
470 .driver = {
471 .name = "dell-smbios",
472 },
473 };
474
build_tokens_sysfs(struct platform_device * dev)475 static int build_tokens_sysfs(struct platform_device *dev)
476 {
477 char *location_name;
478 char *value_name;
479 size_t size;
480 int ret;
481 int i, j;
482
483 /* (number of tokens + 1 for null terminated */
484 size = sizeof(struct device_attribute) * (da_num_tokens + 1);
485 token_location_attrs = kzalloc(size, GFP_KERNEL);
486 if (!token_location_attrs)
487 return -ENOMEM;
488 token_value_attrs = kzalloc(size, GFP_KERNEL);
489 if (!token_value_attrs)
490 goto out_allocate_value;
491
492 /* need to store both location and value + terminator*/
493 size = sizeof(struct attribute *) * ((2 * da_num_tokens) + 1);
494 token_attrs = kzalloc(size, GFP_KERNEL);
495 if (!token_attrs)
496 goto out_allocate_attrs;
497
498 for (i = 0, j = 0; i < da_num_tokens; i++) {
499 /* skip empty */
500 if (da_tokens[i].tokenID == 0)
501 continue;
502 /* add location */
503 location_name = kasprintf(GFP_KERNEL, "%04x_location",
504 da_tokens[i].tokenID);
505 if (location_name == NULL)
506 goto out_unwind_strings;
507 sysfs_attr_init(&token_location_attrs[i].attr);
508 token_location_attrs[i].attr.name = location_name;
509 token_location_attrs[i].attr.mode = 0444;
510 token_location_attrs[i].show = location_show;
511 token_attrs[j++] = &token_location_attrs[i].attr;
512
513 /* add value */
514 value_name = kasprintf(GFP_KERNEL, "%04x_value",
515 da_tokens[i].tokenID);
516 if (value_name == NULL)
517 goto loop_fail_create_value;
518 sysfs_attr_init(&token_value_attrs[i].attr);
519 token_value_attrs[i].attr.name = value_name;
520 token_value_attrs[i].attr.mode = 0444;
521 token_value_attrs[i].show = value_show;
522 token_attrs[j++] = &token_value_attrs[i].attr;
523 continue;
524
525 loop_fail_create_value:
526 kfree(location_name);
527 goto out_unwind_strings;
528 }
529 smbios_attribute_group.attrs = token_attrs;
530
531 ret = sysfs_create_group(&dev->dev.kobj, &smbios_attribute_group);
532 if (ret)
533 goto out_unwind_strings;
534 return 0;
535
536 out_unwind_strings:
537 while (i--) {
538 kfree(token_location_attrs[i].attr.name);
539 kfree(token_value_attrs[i].attr.name);
540 }
541 kfree(token_attrs);
542 out_allocate_attrs:
543 kfree(token_value_attrs);
544 out_allocate_value:
545 kfree(token_location_attrs);
546
547 return -ENOMEM;
548 }
549
free_group(struct platform_device * pdev)550 static void free_group(struct platform_device *pdev)
551 {
552 int i;
553
554 sysfs_remove_group(&pdev->dev.kobj,
555 &smbios_attribute_group);
556 for (i = 0; i < da_num_tokens; i++) {
557 kfree(token_location_attrs[i].attr.name);
558 kfree(token_value_attrs[i].attr.name);
559 }
560 kfree(token_attrs);
561 kfree(token_value_attrs);
562 kfree(token_location_attrs);
563 }
564
dell_smbios_init(void)565 static int __init dell_smbios_init(void)
566 {
567 int ret, wmi, smm;
568
569 if (!dmi_find_device(DMI_DEV_TYPE_OEM_STRING, "Dell System", NULL) &&
570 !dmi_find_device(DMI_DEV_TYPE_OEM_STRING, "www.dell.com", NULL)) {
571 pr_err("Unable to run on non-Dell system\n");
572 return -ENODEV;
573 }
574
575 dmi_walk(find_tokens, NULL);
576
577 ret = platform_driver_register(&platform_driver);
578 if (ret)
579 goto fail_platform_driver;
580
581 platform_device = platform_device_alloc("dell-smbios", 0);
582 if (!platform_device) {
583 ret = -ENOMEM;
584 goto fail_platform_device_alloc;
585 }
586 ret = platform_device_add(platform_device);
587 if (ret)
588 goto fail_platform_device_add;
589
590 /* register backends */
591 wmi = init_dell_smbios_wmi();
592 if (wmi)
593 pr_debug("Failed to initialize WMI backend: %d\n", wmi);
594 smm = init_dell_smbios_smm();
595 if (smm)
596 pr_debug("Failed to initialize SMM backend: %d\n", smm);
597 if (wmi && smm) {
598 pr_err("No SMBIOS backends available (wmi: %d, smm: %d)\n",
599 wmi, smm);
600 goto fail_create_group;
601 }
602
603 if (da_tokens) {
604 /* duplicate tokens will cause problems building sysfs files */
605 zero_duplicates(&platform_device->dev);
606
607 ret = build_tokens_sysfs(platform_device);
608 if (ret)
609 goto fail_sysfs;
610 }
611
612 return 0;
613
614 fail_sysfs:
615 free_group(platform_device);
616
617 fail_create_group:
618 platform_device_del(platform_device);
619
620 fail_platform_device_add:
621 platform_device_put(platform_device);
622
623 fail_platform_device_alloc:
624 platform_driver_unregister(&platform_driver);
625
626 fail_platform_driver:
627 kfree(da_tokens);
628 return ret;
629 }
630
dell_smbios_exit(void)631 static void __exit dell_smbios_exit(void)
632 {
633 exit_dell_smbios_wmi();
634 exit_dell_smbios_smm();
635 mutex_lock(&smbios_mutex);
636 if (platform_device) {
637 if (da_tokens)
638 free_group(platform_device);
639 platform_device_unregister(platform_device);
640 platform_driver_unregister(&platform_driver);
641 }
642 kfree(da_tokens);
643 mutex_unlock(&smbios_mutex);
644 }
645
646 module_init(dell_smbios_init);
647 module_exit(dell_smbios_exit);
648
649 MODULE_AUTHOR("Matthew Garrett <mjg@redhat.com>");
650 MODULE_AUTHOR("Gabriele Mazzotta <gabriele.mzt@gmail.com>");
651 MODULE_AUTHOR("Pali Rohár <pali.rohar@gmail.com>");
652 MODULE_AUTHOR("Mario Limonciello <mario.limonciello@dell.com>");
653 MODULE_DESCRIPTION("Common functions for kernel modules using Dell SMBIOS");
654 MODULE_LICENSE("GPL");
655