dell-smbios-base.c

  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 *  Common functions for kernel modules using Dell SMBIOS
  4 *
  5 *  Copyright (c) Red Hat <mjg@redhat.com>
  6 *  Copyright (c) 2014 Gabriele Mazzotta <gabriele.mzt@gmail.com>
  7 *  Copyright (c) 2014 Pali Rohár <pali@kernel.org>
  8 *
  9 *  Based on documentation in the libsmbios package:
 10 *  Copyright (C) 2005-2014 Dell Inc.
 11 */
 12#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 13
 14#include <linux/container_of.h>
 15#include <linux/kernel.h>
 16#include <linux/module.h>
 17#include <linux/capability.h>
 18#include <linux/dmi.h>
 19#include <linux/err.h>
 20#include <linux/mutex.h>
 21#include <linux/platform_device.h>
 22#include <linux/slab.h>
 23#include "dell-smbios.h"
 24
 25static u32 da_supported_commands;
 26static int da_num_tokens;
 27static struct platform_device *platform_device;
 28static struct calling_interface_token *da_tokens;
 29static struct token_sysfs_data *token_entries;
 30static struct attribute **token_attrs;
 31static DEFINE_MUTEX(smbios_mutex);
 32
 33struct token_sysfs_data {
 34	struct device_attribute location_attr;
 35	struct device_attribute value_attr;
 36	struct calling_interface_token *token;
 37};
 38
 39struct smbios_device {
 40	struct list_head list;
 41	struct device *device;
 42	int priority;
 43	int (*call_fn)(struct calling_interface_buffer *arg);
 44};
 45
 46struct smbios_call {
 47	u32 need_capability;
 48	int cmd_class;
 49	int cmd_select;
 50};
 51
 52/* calls that are whitelisted for given capabilities */
 53static struct smbios_call call_whitelist[] = {
 54	/* generally tokens are allowed, but may be further filtered or
 55	 * restricted by token blacklist or whitelist
 56	 */
 57	{CAP_SYS_ADMIN,	CLASS_TOKEN_READ,	SELECT_TOKEN_STD},
 58	{CAP_SYS_ADMIN,	CLASS_TOKEN_READ,	SELECT_TOKEN_AC},
 59	{CAP_SYS_ADMIN,	CLASS_TOKEN_READ,	SELECT_TOKEN_BAT},
 60	{CAP_SYS_ADMIN,	CLASS_TOKEN_WRITE,	SELECT_TOKEN_STD},
 61	{CAP_SYS_ADMIN,	CLASS_TOKEN_WRITE,	SELECT_TOKEN_AC},
 62	{CAP_SYS_ADMIN,	CLASS_TOKEN_WRITE,	SELECT_TOKEN_BAT},
 63	/* used by userspace: fwupdate */
 64	{CAP_SYS_ADMIN, CLASS_ADMIN_PROP,	SELECT_ADMIN_PROP},
 65	/* used by userspace: fwupd */
 66	{CAP_SYS_ADMIN,	CLASS_INFO,		SELECT_DOCK},
 67	{CAP_SYS_ADMIN,	CLASS_FLASH_INTERFACE,	SELECT_FLASH_INTERFACE},
 68};
 69
 70/* calls that are explicitly blacklisted */
 71static struct smbios_call call_blacklist[] = {
 72	{0x0000,  1,  7}, /* manufacturing use */
 73	{0x0000,  6,  5}, /* manufacturing use */
 74	{0x0000, 11,  3}, /* write once */
 75	{0x0000, 11,  7}, /* write once */
 76	{0x0000, 11, 11}, /* write once */
 77	{0x0000, 19, -1}, /* diagnostics */
 78	/* handled by kernel: dell-laptop */
 79	{0x0000, CLASS_INFO, SELECT_RFKILL},
 80	{0x0000, CLASS_KBD_BACKLIGHT, SELECT_KBD_BACKLIGHT},
 81	{0x0000, CLASS_INFO, SELECT_THERMAL_MANAGEMENT},
 82};
 83
 84struct token_range {
 85	u32 need_capability;
 86	u16 min;
 87	u16 max;
 88};
 89
 90/* tokens that are whitelisted for given capabilities */
 91static struct token_range token_whitelist[] = {
 92	/* used by userspace: fwupdate */
 93	{CAP_SYS_ADMIN,	CAPSULE_EN_TOKEN,	CAPSULE_DIS_TOKEN},
 94	/* can indicate to userspace that WMI is needed */
 95	{0x0000,	WSMT_EN_TOKEN,		WSMT_DIS_TOKEN}
 96};
 97
 98/* tokens that are explicitly blacklisted */
 99static struct token_range token_blacklist[] = {
100	{0x0000, 0x0058, 0x0059}, /* ME use */
101	{0x0000, 0x00CD, 0x00D0}, /* raid shadow copy */
102	{0x0000, 0x013A, 0x01FF}, /* sata shadow copy */
103	{0x0000, 0x0175, 0x0176}, /* write once */
104	{0x0000, 0x0195, 0x0197}, /* diagnostics */
105	{0x0000, 0x01DC, 0x01DD}, /* manufacturing use */
106	{0x0000, 0x027D, 0x0284}, /* diagnostics */
107	{0x0000, 0x02E3, 0x02E3}, /* manufacturing use */
108	{0x0000, 0x02FF, 0x02FF}, /* manufacturing use */
109	{0x0000, 0x0300, 0x0302}, /* manufacturing use */
110	{0x0000, 0x0325, 0x0326}, /* manufacturing use */
111	{0x0000, 0x0332, 0x0335}, /* fan control */
112	{0x0000, 0x0350, 0x0350}, /* manufacturing use */
113	{0x0000, 0x0363, 0x0363}, /* manufacturing use */
114	{0x0000, 0x0368, 0x0368}, /* manufacturing use */
115	{0x0000, 0x03F6, 0x03F7}, /* manufacturing use */
116	{0x0000, 0x049E, 0x049F}, /* manufacturing use */
117	{0x0000, 0x04A0, 0x04A3}, /* disagnostics */
118	{0x0000, 0x04E6, 0x04E7}, /* manufacturing use */
119	{0x0000, 0x4000, 0x7FFF}, /* internal BIOS use */
120	{0x0000, 0x9000, 0x9001}, /* internal BIOS use */
121	{0x0000, 0xA000, 0xBFFF}, /* write only */
122	{0x0000, 0xEFF0, 0xEFFF}, /* internal BIOS use */
123	/* handled by kernel: dell-laptop */
124	{0x0000, BRIGHTNESS_TOKEN,	BRIGHTNESS_TOKEN},
125	{0x0000, KBD_LED_OFF_TOKEN,	KBD_LED_AUTO_TOKEN},
126	{0x0000, KBD_LED_AC_TOKEN,	KBD_LED_AC_TOKEN},
127	{0x0000, KBD_LED_AUTO_25_TOKEN,	KBD_LED_AUTO_75_TOKEN},
128	{0x0000, KBD_LED_AUTO_100_TOKEN,	KBD_LED_AUTO_100_TOKEN},
129	{0x0000, GLOBAL_MIC_MUTE_ENABLE,	GLOBAL_MIC_MUTE_DISABLE},
130};
131
132static LIST_HEAD(smbios_device_list);
133
134int dell_smbios_error(int value)
135{
136	switch (value) {
137	case 0: /* Completed successfully */
138		return 0;
139	case -1: /* Completed with error */
140		return -EIO;
141	case -2: /* Function not supported */
142		return -ENXIO;
143	default: /* Unknown error */
144		return -EINVAL;
145	}
146}
147EXPORT_SYMBOL_GPL(dell_smbios_error);
148
149int dell_smbios_register_device(struct device *d, int priority, void *call_fn)
150{
151	struct smbios_device *priv;
152
153	priv = devm_kzalloc(d, sizeof(struct smbios_device), GFP_KERNEL);
154	if (!priv)
155		return -ENOMEM;
156	get_device(d);
157	priv->device = d;
158	priv->priority = priority;
159	priv->call_fn = call_fn;
160	mutex_lock(&smbios_mutex);
161	list_add_tail(&priv->list, &smbios_device_list);
162	mutex_unlock(&smbios_mutex);
163	dev_dbg(d, "Added device: %s\n", d->driver->name);
164	return 0;
165}
166EXPORT_SYMBOL_GPL(dell_smbios_register_device);
167
168void dell_smbios_unregister_device(struct device *d)
169{
170	struct smbios_device *priv;
171
172	mutex_lock(&smbios_mutex);
173	list_for_each_entry(priv, &smbios_device_list, list) {
174		if (priv->device == d) {
175			list_del(&priv->list);
176			put_device(d);
177			break;
178		}
179	}
180	mutex_unlock(&smbios_mutex);
181	dev_dbg(d, "Remove device: %s\n", d->driver->name);
182}
183EXPORT_SYMBOL_GPL(dell_smbios_unregister_device);
184
185int dell_smbios_call_filter(struct device *d,
186			    struct calling_interface_buffer *buffer)
187{
188	u16 t = 0;
189	int i;
190
191	/* can't make calls over 30 */
192	if (buffer->cmd_class > 30) {
193		dev_dbg(d, "class too big: %u\n", buffer->cmd_class);
194		return -EINVAL;
195	}
196
197	/* supported calls on the particular system */
198	if (!(da_supported_commands & (1 << buffer->cmd_class))) {
199		dev_dbg(d, "invalid command, supported commands: 0x%8x\n",
200			da_supported_commands);
201		return -EINVAL;
202	}
203
204	/* match against call blacklist  */
205	for (i = 0; i < ARRAY_SIZE(call_blacklist); i++) {
206		if (buffer->cmd_class != call_blacklist[i].cmd_class)
207			continue;
208		if (buffer->cmd_select != call_blacklist[i].cmd_select &&
209		    call_blacklist[i].cmd_select != -1)
210			continue;
211		dev_dbg(d, "blacklisted command: %u/%u\n",
212			buffer->cmd_class, buffer->cmd_select);
213		return -EINVAL;
214	}
215
216	/* if a token call, find token ID */
217
218	if ((buffer->cmd_class == CLASS_TOKEN_READ ||
219	     buffer->cmd_class == CLASS_TOKEN_WRITE) &&
220	     buffer->cmd_select < 3) {
221		/* tokens enabled ? */
222		if (!da_tokens) {
223			dev_dbg(d, "no token support on this system\n");
224			return -EINVAL;
225		}
226
227		/* find the matching token ID */
228		for (i = 0; i < da_num_tokens; i++) {
229			if (da_tokens[i].location != buffer->input[0])
230				continue;
231			t = da_tokens[i].tokenID;
232			break;
233		}
234
235		/* token call; but token didn't exist */
236		if (!t) {
237			dev_dbg(d, "token at location %04x doesn't exist\n",
238				buffer->input[0]);
239			return -EINVAL;
240		}
241
242		/* match against token blacklist */
243		for (i = 0; i < ARRAY_SIZE(token_blacklist); i++) {
244			if (!token_blacklist[i].min || !token_blacklist[i].max)
245				continue;
246			if (t >= token_blacklist[i].min &&
247			    t <= token_blacklist[i].max)
248				return -EINVAL;
249		}
250
251		/* match against token whitelist */
252		for (i = 0; i < ARRAY_SIZE(token_whitelist); i++) {
253			if (!token_whitelist[i].min || !token_whitelist[i].max)
254				continue;
255			if (t < token_whitelist[i].min ||
256			    t > token_whitelist[i].max)
257				continue;
258			if (!token_whitelist[i].need_capability ||
259			    capable(token_whitelist[i].need_capability)) {
260				dev_dbg(d, "whitelisted token: %x\n", t);
261				return 0;
262			}
263
264		}
265	}
266	/* match against call whitelist */
267	for (i = 0; i < ARRAY_SIZE(call_whitelist); i++) {
268		if (buffer->cmd_class != call_whitelist[i].cmd_class)
269			continue;
270		if (buffer->cmd_select != call_whitelist[i].cmd_select)
271			continue;
272		if (!call_whitelist[i].need_capability ||
273		    capable(call_whitelist[i].need_capability)) {
274			dev_dbg(d, "whitelisted capable command: %u/%u\n",
275			buffer->cmd_class, buffer->cmd_select);
276			return 0;
277		}
278		dev_dbg(d, "missing capability %d for %u/%u\n",
279			call_whitelist[i].need_capability,
280			buffer->cmd_class, buffer->cmd_select);
281
282	}
283
284	/* not in a whitelist, only allow processes with capabilities */
285	if (capable(CAP_SYS_RAWIO)) {
286		dev_dbg(d, "Allowing %u/%u due to CAP_SYS_RAWIO\n",
287			buffer->cmd_class, buffer->cmd_select);
288		return 0;
289	}
290
291	return -EACCES;
292}
293EXPORT_SYMBOL_GPL(dell_smbios_call_filter);
294
295int dell_smbios_call(struct calling_interface_buffer *buffer)
296{
297	struct smbios_device *selected = NULL;
298	struct smbios_device *priv;
299	int ret;
300
301	mutex_lock(&smbios_mutex);
302	list_for_each_entry(priv, &smbios_device_list, list) {
303		if (!selected || priv->priority >= selected->priority) {
304			dev_dbg(priv->device, "Trying device ID: %d\n", priv->priority);
305			selected = priv;
306		}
307	}
308
309	if (!selected) {
310		ret = -ENODEV;
311		pr_err("No dell-smbios drivers are loaded\n");
312		goto out_smbios_call;
313	}
314
315	ret = selected->call_fn(buffer);
316
317out_smbios_call:
318	mutex_unlock(&smbios_mutex);
319	return ret;
320}
321EXPORT_SYMBOL_GPL(dell_smbios_call);
322
323void dell_fill_request(struct calling_interface_buffer *buffer,
324			       u32 arg0, u32 arg1, u32 arg2, u32 arg3)
325{
326	memset(buffer, 0, sizeof(struct calling_interface_buffer));
327	buffer->input[0] = arg0;
328	buffer->input[1] = arg1;
329	buffer->input[2] = arg2;
330	buffer->input[3] = arg3;
331}
332EXPORT_SYMBOL_GPL(dell_fill_request);
333
334int dell_send_request(struct calling_interface_buffer *buffer,
335			     u16 class, u16 select)
336{
337	int ret;
338
339	buffer->cmd_class = class;
340	buffer->cmd_select = select;
341	ret = dell_smbios_call(buffer);
342	if (ret != 0)
343		return ret;
344	return dell_smbios_error(buffer->output[0]);
345}
346EXPORT_SYMBOL_GPL(dell_send_request);
347
348struct calling_interface_token *dell_smbios_find_token(int tokenid)
349{
350	int i;
351
352	if (!da_tokens)
353		return NULL;
354
355	for (i = 0; i < da_num_tokens; i++) {
356		if (da_tokens[i].tokenID == tokenid)
357			return &da_tokens[i];
358	}
359
360	return NULL;
361}
362EXPORT_SYMBOL_GPL(dell_smbios_find_token);
363
364static BLOCKING_NOTIFIER_HEAD(dell_laptop_chain_head);
365
366int dell_laptop_register_notifier(struct notifier_block *nb)
367{
368	return blocking_notifier_chain_register(&dell_laptop_chain_head, nb);
369}
370EXPORT_SYMBOL_GPL(dell_laptop_register_notifier);
371
372int dell_laptop_unregister_notifier(struct notifier_block *nb)
373{
374	return blocking_notifier_chain_unregister(&dell_laptop_chain_head, nb);
375}
376EXPORT_SYMBOL_GPL(dell_laptop_unregister_notifier);
377
378void dell_laptop_call_notifier(unsigned long action, void *data)
379{
380	blocking_notifier_call_chain(&dell_laptop_chain_head, action, data);
381}
382EXPORT_SYMBOL_GPL(dell_laptop_call_notifier);
383
384bool dell_smbios_class_is_supported(u16 class)
385{
386	/* Classes over 30 always unsupported */
387	if (class > 30)
388		return false;
389	return da_supported_commands & (1 << class);
390}
391EXPORT_SYMBOL_GPL(dell_smbios_class_is_supported);
392
393static void __init parse_da_table(const struct dmi_header *dm)
394{
395	/* Final token is a terminator, so we don't want to copy it */
396	int tokens = (dm->length-11)/sizeof(struct calling_interface_token)-1;
397	struct calling_interface_token *new_da_tokens;
398	struct calling_interface_structure *table =
399		container_of(dm, struct calling_interface_structure, header);
400
401	/*
402	 * 4 bytes of table header, plus 7 bytes of Dell header
403	 * plus at least 6 bytes of entry
404	 */
405
406	if (dm->length < 17)
407		return;
408
409	da_supported_commands = table->supportedCmds;
410
411	new_da_tokens = krealloc(da_tokens, (da_num_tokens + tokens) *
412				 sizeof(struct calling_interface_token),
413				 GFP_KERNEL);
414
415	if (!new_da_tokens)
416		return;
417	da_tokens = new_da_tokens;
418
419	memcpy(da_tokens+da_num_tokens, table->tokens,
420	       sizeof(struct calling_interface_token) * tokens);
421
422	da_num_tokens += tokens;
423}
424
425static void zero_duplicates(struct device *dev)
426{
427	int i, j;
428
429	for (i = 0; i < da_num_tokens; i++) {
430		if (da_tokens[i].tokenID == 0)
431			continue;
432		for (j = i+1; j < da_num_tokens; j++) {
433			if (da_tokens[j].tokenID == 0)
434				continue;
435			if (da_tokens[i].tokenID == da_tokens[j].tokenID) {
436				dev_dbg(dev, "Zeroing dup token ID %x(%x/%x)\n",
437					da_tokens[j].tokenID,
438					da_tokens[j].location,
439					da_tokens[j].value);
440				da_tokens[j].tokenID = 0;
441			}
442		}
443	}
444}
445
446static void __init find_tokens(const struct dmi_header *dm, void *dummy)
447{
448	switch (dm->type) {
449	case 0xd4: /* Indexed IO */
450	case 0xd5: /* Protected Area Type 1 */
451	case 0xd6: /* Protected Area Type 2 */
452		break;
453	case 0xda: /* Calling interface */
454		parse_da_table(dm);
455		break;
456	}
457}
458
459static ssize_t location_show(struct device *dev,
460			     struct device_attribute *attr, char *buf)
461{
462	struct token_sysfs_data *data = container_of(attr, struct token_sysfs_data, location_attr);
463
464	if (!capable(CAP_SYS_ADMIN))
465		return -EPERM;
466
467	return sysfs_emit(buf, "%08x", data->token->location);
468}
469
470static ssize_t value_show(struct device *dev,
471			  struct device_attribute *attr, char *buf)
472{
473	struct token_sysfs_data *data = container_of(attr, struct token_sysfs_data, value_attr);
474
475	if (!capable(CAP_SYS_ADMIN))
476		return -EPERM;
477
478	return sysfs_emit(buf, "%08x", data->token->value);
479}
480
481static struct attribute_group smbios_attribute_group = {
482	.name = "tokens"
483};
484
485static struct platform_driver platform_driver = {
486	.driver = {
487		.name = "dell-smbios",
488	},
489};
490
491static int build_tokens_sysfs(struct platform_device *dev)
492{
493	char *location_name;
494	char *value_name;
495	int ret;
496	int i, j;
497
498	token_entries = kcalloc(da_num_tokens, sizeof(*token_entries), GFP_KERNEL);
499	if (!token_entries)
500		return -ENOMEM;
501
502	/* need to store both location and value + terminator*/
503	token_attrs = kcalloc((2 * da_num_tokens) + 1, sizeof(*token_attrs), GFP_KERNEL);
504	if (!token_attrs)
505		goto out_allocate_attrs;
506
507	for (i = 0, j = 0; i < da_num_tokens; i++) {
508		/* skip empty */
509		if (da_tokens[i].tokenID == 0)
510			continue;
511
512		token_entries[i].token = &da_tokens[i];
513
514		/* add location */
515		location_name = kasprintf(GFP_KERNEL, "%04x_location",
516					  da_tokens[i].tokenID);
517		if (location_name == NULL)
518			goto out_unwind_strings;
519
520		sysfs_attr_init(&token_entries[i].location_attr.attr);
521		token_entries[i].location_attr.attr.name = location_name;
522		token_entries[i].location_attr.attr.mode = 0444;
523		token_entries[i].location_attr.show = location_show;
524		token_attrs[j++] = &token_entries[i].location_attr.attr;
525
526		/* add value */
527		value_name = kasprintf(GFP_KERNEL, "%04x_value",
528				       da_tokens[i].tokenID);
529		if (!value_name) {
530			kfree(location_name);
531			goto out_unwind_strings;
532		}
533
534		sysfs_attr_init(&token_entries[i].value_attr.attr);
535		token_entries[i].value_attr.attr.name = value_name;
536		token_entries[i].value_attr.attr.mode = 0444;
537		token_entries[i].value_attr.show = value_show;
538		token_attrs[j++] = &token_entries[i].value_attr.attr;
539	}
540	smbios_attribute_group.attrs = token_attrs;
541
542	ret = sysfs_create_group(&dev->dev.kobj, &smbios_attribute_group);
543	if (ret)
544		goto out_unwind_strings;
545	return 0;
546
547out_unwind_strings:
548	while (i--) {
549		kfree(token_entries[i].location_attr.attr.name);
550		kfree(token_entries[i].value_attr.attr.name);
551	}
552	kfree(token_attrs);
553out_allocate_attrs:
554	kfree(token_entries);
555
556	return -ENOMEM;
557}
558
559static void free_group(struct platform_device *pdev)
560{
561	int i;
562
563	sysfs_remove_group(&pdev->dev.kobj,
564				&smbios_attribute_group);
565	for (i = 0; i < da_num_tokens; i++) {
566		kfree(token_entries[i].location_attr.attr.name);
567		kfree(token_entries[i].value_attr.attr.name);
568	}
569	kfree(token_attrs);
570	kfree(token_entries);
571}
572
573static int __init dell_smbios_init(void)
574{
575	int ret, wmi, smm;
576
577	if (!dmi_find_device(DMI_DEV_TYPE_OEM_STRING, "Dell System", NULL) &&
578	    !dmi_find_device(DMI_DEV_TYPE_OEM_STRING, "Alienware", NULL) &&
579	    !dmi_find_device(DMI_DEV_TYPE_OEM_STRING, "www.dell.com", NULL)) {
580		pr_err("Unable to run on non-Dell system\n");
581		return -ENODEV;
582	}
583
584	dmi_walk(find_tokens, NULL);
585
586	ret = platform_driver_register(&platform_driver);
587	if (ret)
588		goto fail_platform_driver;
589
590	platform_device = platform_device_alloc("dell-smbios", 0);
591	if (!platform_device) {
592		ret = -ENOMEM;
593		goto fail_platform_device_alloc;
594	}
595	ret = platform_device_add(platform_device);
596	if (ret)
597		goto fail_platform_device_add;
598
599	/* register backends */
600	wmi = init_dell_smbios_wmi();
601	if (wmi)
602		pr_debug("Failed to initialize WMI backend: %d\n", wmi);
603	smm = init_dell_smbios_smm();
604	if (smm)
605		pr_debug("Failed to initialize SMM backend: %d\n", smm);
606	if (wmi && smm) {
607		pr_err("No SMBIOS backends available (wmi: %d, smm: %d)\n",
608			wmi, smm);
609		ret = -ENODEV;
610		goto fail_create_group;
611	}
612
613	if (da_tokens)  {
614		/* duplicate tokens will cause problems building sysfs files */
615		zero_duplicates(&platform_device->dev);
616
617		ret = build_tokens_sysfs(platform_device);
618		if (ret)
619			goto fail_sysfs;
620	}
621
622	return 0;
623
624fail_sysfs:
625	if (!wmi)
626		exit_dell_smbios_wmi();
627	if (!smm)
628		exit_dell_smbios_smm();
629
630fail_create_group:
631	platform_device_del(platform_device);
632
633fail_platform_device_add:
634	platform_device_put(platform_device);
635
636fail_platform_device_alloc:
637	platform_driver_unregister(&platform_driver);
638
639fail_platform_driver:
640	kfree(da_tokens);
641	return ret;
642}
643
644static void __exit dell_smbios_exit(void)
645{
646	exit_dell_smbios_wmi();
647	exit_dell_smbios_smm();
648	mutex_lock(&smbios_mutex);
649	if (platform_device) {
650		if (da_tokens)
651			free_group(platform_device);
652		platform_device_unregister(platform_device);
653		platform_driver_unregister(&platform_driver);
654	}
655	kfree(da_tokens);
656	mutex_unlock(&smbios_mutex);
657}
658
659module_init(dell_smbios_init);
660module_exit(dell_smbios_exit);
661
662MODULE_AUTHOR("Matthew Garrett <mjg@redhat.com>");
663MODULE_AUTHOR("Gabriele Mazzotta <gabriele.mzt@gmail.com>");
664MODULE_AUTHOR("Pali Rohár <pali@kernel.org>");
665MODULE_AUTHOR("Mario Limonciello <mario.limonciello@outlook.com>");
666MODULE_DESCRIPTION("Common functions for kernel modules using Dell SMBIOS");
667MODULE_LICENSE("GPL");