[go: nahoru, domu]

1/*
2 * i8k.c -- Linux driver for accessing the SMM BIOS on Dell laptops.
3 *
4 * Copyright (C) 2001  Massimo Dal Zotto <dz@debian.org>
5 *
6 * Hwmon integration:
7 * Copyright (C) 2011  Jean Delvare <jdelvare@suse.de>
8 * Copyright (C) 2013  Guenter Roeck <linux@roeck-us.net>
9 *
10 * This program is free software; you can redistribute it and/or modify it
11 * under the terms of the GNU General Public License as published by the
12 * Free Software Foundation; either version 2, or (at your option) any
13 * later version.
14 *
15 * This program is distributed in the hope that it will be useful, but
16 * WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
18 * General Public License for more details.
19 */
20
21#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
22
23#include <linux/module.h>
24#include <linux/types.h>
25#include <linux/init.h>
26#include <linux/proc_fs.h>
27#include <linux/seq_file.h>
28#include <linux/dmi.h>
29#include <linux/capability.h>
30#include <linux/mutex.h>
31#include <linux/hwmon.h>
32#include <linux/hwmon-sysfs.h>
33#include <linux/uaccess.h>
34#include <linux/io.h>
35#include <linux/sched.h>
36
37#include <linux/i8k.h>
38
39#define I8K_SMM_FN_STATUS	0x0025
40#define I8K_SMM_POWER_STATUS	0x0069
41#define I8K_SMM_SET_FAN		0x01a3
42#define I8K_SMM_GET_FAN		0x00a3
43#define I8K_SMM_GET_SPEED	0x02a3
44#define I8K_SMM_GET_TEMP	0x10a3
45#define I8K_SMM_GET_DELL_SIG1	0xfea3
46#define I8K_SMM_GET_DELL_SIG2	0xffa3
47
48#define I8K_FAN_MULT		30
49#define I8K_MAX_TEMP		127
50
51#define I8K_FN_NONE		0x00
52#define I8K_FN_UP		0x01
53#define I8K_FN_DOWN		0x02
54#define I8K_FN_MUTE		0x04
55#define I8K_FN_MASK		0x07
56#define I8K_FN_SHIFT		8
57
58#define I8K_POWER_AC		0x05
59#define I8K_POWER_BATTERY	0x01
60
61#define I8K_TEMPERATURE_BUG	1
62
63static DEFINE_MUTEX(i8k_mutex);
64static char bios_version[4];
65static struct device *i8k_hwmon_dev;
66static u32 i8k_hwmon_flags;
67static int i8k_fan_mult;
68static int i8k_pwm_mult;
69static int i8k_fan_max = I8K_FAN_HIGH;
70
71#define I8K_HWMON_HAVE_TEMP1	(1 << 0)
72#define I8K_HWMON_HAVE_TEMP2	(1 << 1)
73#define I8K_HWMON_HAVE_TEMP3	(1 << 2)
74#define I8K_HWMON_HAVE_TEMP4	(1 << 3)
75#define I8K_HWMON_HAVE_FAN1	(1 << 4)
76#define I8K_HWMON_HAVE_FAN2	(1 << 5)
77
78MODULE_AUTHOR("Massimo Dal Zotto (dz@debian.org)");
79MODULE_DESCRIPTION("Driver for accessing SMM BIOS on Dell laptops");
80MODULE_LICENSE("GPL");
81
82static bool force;
83module_param(force, bool, 0);
84MODULE_PARM_DESC(force, "Force loading without checking for supported models");
85
86static bool ignore_dmi;
87module_param(ignore_dmi, bool, 0);
88MODULE_PARM_DESC(ignore_dmi, "Continue probing hardware even if DMI data does not match");
89
90static bool restricted;
91module_param(restricted, bool, 0);
92MODULE_PARM_DESC(restricted, "Allow fan control if SYS_ADMIN capability set");
93
94static bool power_status;
95module_param(power_status, bool, 0600);
96MODULE_PARM_DESC(power_status, "Report power status in /proc/i8k");
97
98static int fan_mult = I8K_FAN_MULT;
99module_param(fan_mult, int, 0);
100MODULE_PARM_DESC(fan_mult, "Factor to multiply fan speed with");
101
102static int fan_max = I8K_FAN_HIGH;
103module_param(fan_max, int, 0);
104MODULE_PARM_DESC(fan_max, "Maximum configurable fan speed");
105
106static int i8k_open_fs(struct inode *inode, struct file *file);
107static long i8k_ioctl(struct file *, unsigned int, unsigned long);
108
109static const struct file_operations i8k_fops = {
110	.owner		= THIS_MODULE,
111	.open		= i8k_open_fs,
112	.read		= seq_read,
113	.llseek		= seq_lseek,
114	.release	= single_release,
115	.unlocked_ioctl	= i8k_ioctl,
116};
117
118struct smm_regs {
119	unsigned int eax;
120	unsigned int ebx __packed;
121	unsigned int ecx __packed;
122	unsigned int edx __packed;
123	unsigned int esi __packed;
124	unsigned int edi __packed;
125};
126
127static inline const char *i8k_get_dmi_data(int field)
128{
129	const char *dmi_data = dmi_get_system_info(field);
130
131	return dmi_data && *dmi_data ? dmi_data : "?";
132}
133
134/*
135 * Call the System Management Mode BIOS. Code provided by Jonathan Buzzard.
136 */
137static int i8k_smm(struct smm_regs *regs)
138{
139	int rc;
140	int eax = regs->eax;
141	cpumask_var_t old_mask;
142
143	/* SMM requires CPU 0 */
144	if (!alloc_cpumask_var(&old_mask, GFP_KERNEL))
145		return -ENOMEM;
146	cpumask_copy(old_mask, &current->cpus_allowed);
147	rc = set_cpus_allowed_ptr(current, cpumask_of(0));
148	if (rc)
149		goto out;
150	if (smp_processor_id() != 0) {
151		rc = -EBUSY;
152		goto out;
153	}
154
155#if defined(CONFIG_X86_64)
156	asm volatile("pushq %%rax\n\t"
157		"movl 0(%%rax),%%edx\n\t"
158		"pushq %%rdx\n\t"
159		"movl 4(%%rax),%%ebx\n\t"
160		"movl 8(%%rax),%%ecx\n\t"
161		"movl 12(%%rax),%%edx\n\t"
162		"movl 16(%%rax),%%esi\n\t"
163		"movl 20(%%rax),%%edi\n\t"
164		"popq %%rax\n\t"
165		"out %%al,$0xb2\n\t"
166		"out %%al,$0x84\n\t"
167		"xchgq %%rax,(%%rsp)\n\t"
168		"movl %%ebx,4(%%rax)\n\t"
169		"movl %%ecx,8(%%rax)\n\t"
170		"movl %%edx,12(%%rax)\n\t"
171		"movl %%esi,16(%%rax)\n\t"
172		"movl %%edi,20(%%rax)\n\t"
173		"popq %%rdx\n\t"
174		"movl %%edx,0(%%rax)\n\t"
175		"pushfq\n\t"
176		"popq %%rax\n\t"
177		"andl $1,%%eax\n"
178		: "=a"(rc)
179		:    "a"(regs)
180		:    "%ebx", "%ecx", "%edx", "%esi", "%edi", "memory");
181#else
182	asm volatile("pushl %%eax\n\t"
183	    "movl 0(%%eax),%%edx\n\t"
184	    "push %%edx\n\t"
185	    "movl 4(%%eax),%%ebx\n\t"
186	    "movl 8(%%eax),%%ecx\n\t"
187	    "movl 12(%%eax),%%edx\n\t"
188	    "movl 16(%%eax),%%esi\n\t"
189	    "movl 20(%%eax),%%edi\n\t"
190	    "popl %%eax\n\t"
191	    "out %%al,$0xb2\n\t"
192	    "out %%al,$0x84\n\t"
193	    "xchgl %%eax,(%%esp)\n\t"
194	    "movl %%ebx,4(%%eax)\n\t"
195	    "movl %%ecx,8(%%eax)\n\t"
196	    "movl %%edx,12(%%eax)\n\t"
197	    "movl %%esi,16(%%eax)\n\t"
198	    "movl %%edi,20(%%eax)\n\t"
199	    "popl %%edx\n\t"
200	    "movl %%edx,0(%%eax)\n\t"
201	    "lahf\n\t"
202	    "shrl $8,%%eax\n\t"
203	    "andl $1,%%eax\n"
204	    : "=a"(rc)
205	    :    "a"(regs)
206	    :    "%ebx", "%ecx", "%edx", "%esi", "%edi", "memory");
207#endif
208	if (rc != 0 || (regs->eax & 0xffff) == 0xffff || regs->eax == eax)
209		rc = -EINVAL;
210
211out:
212	set_cpus_allowed_ptr(current, old_mask);
213	free_cpumask_var(old_mask);
214	return rc;
215}
216
217/*
218 * Read the Fn key status.
219 */
220static int i8k_get_fn_status(void)
221{
222	struct smm_regs regs = { .eax = I8K_SMM_FN_STATUS, };
223	int rc;
224
225	rc = i8k_smm(&regs);
226	if (rc < 0)
227		return rc;
228
229	switch ((regs.eax >> I8K_FN_SHIFT) & I8K_FN_MASK) {
230	case I8K_FN_UP:
231		return I8K_VOL_UP;
232	case I8K_FN_DOWN:
233		return I8K_VOL_DOWN;
234	case I8K_FN_MUTE:
235		return I8K_VOL_MUTE;
236	default:
237		return 0;
238	}
239}
240
241/*
242 * Read the power status.
243 */
244static int i8k_get_power_status(void)
245{
246	struct smm_regs regs = { .eax = I8K_SMM_POWER_STATUS, };
247	int rc;
248
249	rc = i8k_smm(&regs);
250	if (rc < 0)
251		return rc;
252
253	return (regs.eax & 0xff) == I8K_POWER_AC ? I8K_AC : I8K_BATTERY;
254}
255
256/*
257 * Read the fan status.
258 */
259static int i8k_get_fan_status(int fan)
260{
261	struct smm_regs regs = { .eax = I8K_SMM_GET_FAN, };
262
263	regs.ebx = fan & 0xff;
264	return i8k_smm(&regs) ? : regs.eax & 0xff;
265}
266
267/*
268 * Read the fan speed in RPM.
269 */
270static int i8k_get_fan_speed(int fan)
271{
272	struct smm_regs regs = { .eax = I8K_SMM_GET_SPEED, };
273
274	regs.ebx = fan & 0xff;
275	return i8k_smm(&regs) ? : (regs.eax & 0xffff) * i8k_fan_mult;
276}
277
278/*
279 * Set the fan speed (off, low, high). Returns the new fan status.
280 */
281static int i8k_set_fan(int fan, int speed)
282{
283	struct smm_regs regs = { .eax = I8K_SMM_SET_FAN, };
284
285	speed = (speed < 0) ? 0 : ((speed > i8k_fan_max) ? i8k_fan_max : speed);
286	regs.ebx = (fan & 0xff) | (speed << 8);
287
288	return i8k_smm(&regs) ? : i8k_get_fan_status(fan);
289}
290
291/*
292 * Read the cpu temperature.
293 */
294static int i8k_get_temp(int sensor)
295{
296	struct smm_regs regs = { .eax = I8K_SMM_GET_TEMP, };
297	int rc;
298	int temp;
299
300#ifdef I8K_TEMPERATURE_BUG
301	static int prev[4];
302#endif
303	regs.ebx = sensor & 0xff;
304	rc = i8k_smm(&regs);
305	if (rc < 0)
306		return rc;
307
308	temp = regs.eax & 0xff;
309
310#ifdef I8K_TEMPERATURE_BUG
311	/*
312	 * Sometimes the temperature sensor returns 0x99, which is out of range.
313	 * In this case we return (once) the previous cached value. For example:
314	 # 1003655137 00000058 00005a4b
315	 # 1003655138 00000099 00003a80 <--- 0x99 = 153 degrees
316	 # 1003655139 00000054 00005c52
317	 */
318	if (temp > I8K_MAX_TEMP) {
319		temp = prev[sensor];
320		prev[sensor] = I8K_MAX_TEMP;
321	} else {
322		prev[sensor] = temp;
323	}
324#endif
325
326	return temp;
327}
328
329static int i8k_get_dell_signature(int req_fn)
330{
331	struct smm_regs regs = { .eax = req_fn, };
332	int rc;
333
334	rc = i8k_smm(&regs);
335	if (rc < 0)
336		return rc;
337
338	return regs.eax == 1145651527 && regs.edx == 1145392204 ? 0 : -1;
339}
340
341static int
342i8k_ioctl_unlocked(struct file *fp, unsigned int cmd, unsigned long arg)
343{
344	int val = 0;
345	int speed;
346	unsigned char buff[16];
347	int __user *argp = (int __user *)arg;
348
349	if (!argp)
350		return -EINVAL;
351
352	switch (cmd) {
353	case I8K_BIOS_VERSION:
354		val = (bios_version[0] << 16) |
355				(bios_version[1] << 8) | bios_version[2];
356		break;
357
358	case I8K_MACHINE_ID:
359		memset(buff, 0, 16);
360		strlcpy(buff, i8k_get_dmi_data(DMI_PRODUCT_SERIAL),
361			sizeof(buff));
362		break;
363
364	case I8K_FN_STATUS:
365		val = i8k_get_fn_status();
366		break;
367
368	case I8K_POWER_STATUS:
369		val = i8k_get_power_status();
370		break;
371
372	case I8K_GET_TEMP:
373		val = i8k_get_temp(0);
374		break;
375
376	case I8K_GET_SPEED:
377		if (copy_from_user(&val, argp, sizeof(int)))
378			return -EFAULT;
379
380		val = i8k_get_fan_speed(val);
381		break;
382
383	case I8K_GET_FAN:
384		if (copy_from_user(&val, argp, sizeof(int)))
385			return -EFAULT;
386
387		val = i8k_get_fan_status(val);
388		break;
389
390	case I8K_SET_FAN:
391		if (restricted && !capable(CAP_SYS_ADMIN))
392			return -EPERM;
393
394		if (copy_from_user(&val, argp, sizeof(int)))
395			return -EFAULT;
396
397		if (copy_from_user(&speed, argp + 1, sizeof(int)))
398			return -EFAULT;
399
400		val = i8k_set_fan(val, speed);
401		break;
402
403	default:
404		return -EINVAL;
405	}
406
407	if (val < 0)
408		return val;
409
410	switch (cmd) {
411	case I8K_BIOS_VERSION:
412		if (copy_to_user(argp, &val, 4))
413			return -EFAULT;
414
415		break;
416	case I8K_MACHINE_ID:
417		if (copy_to_user(argp, buff, 16))
418			return -EFAULT;
419
420		break;
421	default:
422		if (copy_to_user(argp, &val, sizeof(int)))
423			return -EFAULT;
424
425		break;
426	}
427
428	return 0;
429}
430
431static long i8k_ioctl(struct file *fp, unsigned int cmd, unsigned long arg)
432{
433	long ret;
434
435	mutex_lock(&i8k_mutex);
436	ret = i8k_ioctl_unlocked(fp, cmd, arg);
437	mutex_unlock(&i8k_mutex);
438
439	return ret;
440}
441
442/*
443 * Print the information for /proc/i8k.
444 */
445static int i8k_proc_show(struct seq_file *seq, void *offset)
446{
447	int fn_key, cpu_temp, ac_power;
448	int left_fan, right_fan, left_speed, right_speed;
449
450	cpu_temp	= i8k_get_temp(0);			/* 11100 µs */
451	left_fan	= i8k_get_fan_status(I8K_FAN_LEFT);	/*   580 µs */
452	right_fan	= i8k_get_fan_status(I8K_FAN_RIGHT);	/*   580 µs */
453	left_speed	= i8k_get_fan_speed(I8K_FAN_LEFT);	/*   580 µs */
454	right_speed	= i8k_get_fan_speed(I8K_FAN_RIGHT);	/*   580 µs */
455	fn_key		= i8k_get_fn_status();			/*   750 µs */
456	if (power_status)
457		ac_power = i8k_get_power_status();		/* 14700 µs */
458	else
459		ac_power = -1;
460
461	/*
462	 * Info:
463	 *
464	 * 1)  Format version (this will change if format changes)
465	 * 2)  BIOS version
466	 * 3)  BIOS machine ID
467	 * 4)  Cpu temperature
468	 * 5)  Left fan status
469	 * 6)  Right fan status
470	 * 7)  Left fan speed
471	 * 8)  Right fan speed
472	 * 9)  AC power
473	 * 10) Fn Key status
474	 */
475	return seq_printf(seq, "%s %s %s %d %d %d %d %d %d %d\n",
476			  I8K_PROC_FMT,
477			  bios_version,
478			  i8k_get_dmi_data(DMI_PRODUCT_SERIAL),
479			  cpu_temp,
480			  left_fan, right_fan, left_speed, right_speed,
481			  ac_power, fn_key);
482}
483
484static int i8k_open_fs(struct inode *inode, struct file *file)
485{
486	return single_open(file, i8k_proc_show, NULL);
487}
488
489
490/*
491 * Hwmon interface
492 */
493
494static ssize_t i8k_hwmon_show_temp(struct device *dev,
495				   struct device_attribute *devattr,
496				   char *buf)
497{
498	int index = to_sensor_dev_attr(devattr)->index;
499	int temp;
500
501	temp = i8k_get_temp(index);
502	if (temp < 0)
503		return temp;
504	return sprintf(buf, "%d\n", temp * 1000);
505}
506
507static ssize_t i8k_hwmon_show_fan(struct device *dev,
508				  struct device_attribute *devattr,
509				  char *buf)
510{
511	int index = to_sensor_dev_attr(devattr)->index;
512	int fan_speed;
513
514	fan_speed = i8k_get_fan_speed(index);
515	if (fan_speed < 0)
516		return fan_speed;
517	return sprintf(buf, "%d\n", fan_speed);
518}
519
520static ssize_t i8k_hwmon_show_pwm(struct device *dev,
521				  struct device_attribute *devattr,
522				  char *buf)
523{
524	int index = to_sensor_dev_attr(devattr)->index;
525	int status;
526
527	status = i8k_get_fan_status(index);
528	if (status < 0)
529		return -EIO;
530	return sprintf(buf, "%d\n", clamp_val(status * i8k_pwm_mult, 0, 255));
531}
532
533static ssize_t i8k_hwmon_set_pwm(struct device *dev,
534				 struct device_attribute *attr,
535				 const char *buf, size_t count)
536{
537	int index = to_sensor_dev_attr(attr)->index;
538	unsigned long val;
539	int err;
540
541	err = kstrtoul(buf, 10, &val);
542	if (err)
543		return err;
544	val = clamp_val(DIV_ROUND_CLOSEST(val, i8k_pwm_mult), 0, i8k_fan_max);
545
546	mutex_lock(&i8k_mutex);
547	err = i8k_set_fan(index, val);
548	mutex_unlock(&i8k_mutex);
549
550	return err < 0 ? -EIO : count;
551}
552
553static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, i8k_hwmon_show_temp, NULL, 0);
554static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, i8k_hwmon_show_temp, NULL, 1);
555static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, i8k_hwmon_show_temp, NULL, 2);
556static SENSOR_DEVICE_ATTR(temp4_input, S_IRUGO, i8k_hwmon_show_temp, NULL, 3);
557static SENSOR_DEVICE_ATTR(fan1_input, S_IRUGO, i8k_hwmon_show_fan, NULL,
558			  I8K_FAN_LEFT);
559static SENSOR_DEVICE_ATTR(pwm1, S_IRUGO | S_IWUSR, i8k_hwmon_show_pwm,
560			  i8k_hwmon_set_pwm, I8K_FAN_LEFT);
561static SENSOR_DEVICE_ATTR(fan2_input, S_IRUGO, i8k_hwmon_show_fan, NULL,
562			  I8K_FAN_RIGHT);
563static SENSOR_DEVICE_ATTR(pwm2, S_IRUGO | S_IWUSR, i8k_hwmon_show_pwm,
564			  i8k_hwmon_set_pwm, I8K_FAN_RIGHT);
565
566static struct attribute *i8k_attrs[] = {
567	&sensor_dev_attr_temp1_input.dev_attr.attr,	/* 0 */
568	&sensor_dev_attr_temp2_input.dev_attr.attr,	/* 1 */
569	&sensor_dev_attr_temp3_input.dev_attr.attr,	/* 2 */
570	&sensor_dev_attr_temp4_input.dev_attr.attr,	/* 3 */
571	&sensor_dev_attr_fan1_input.dev_attr.attr,	/* 4 */
572	&sensor_dev_attr_pwm1.dev_attr.attr,		/* 5 */
573	&sensor_dev_attr_fan2_input.dev_attr.attr,	/* 6 */
574	&sensor_dev_attr_pwm2.dev_attr.attr,		/* 7 */
575	NULL
576};
577
578static umode_t i8k_is_visible(struct kobject *kobj, struct attribute *attr,
579			      int index)
580{
581	if (index == 0 && !(i8k_hwmon_flags & I8K_HWMON_HAVE_TEMP1))
582		return 0;
583	if (index == 1 && !(i8k_hwmon_flags & I8K_HWMON_HAVE_TEMP2))
584		return 0;
585	if (index == 2 && !(i8k_hwmon_flags & I8K_HWMON_HAVE_TEMP3))
586		return 0;
587	if (index == 3 && !(i8k_hwmon_flags & I8K_HWMON_HAVE_TEMP4))
588		return 0;
589	if (index >= 4 && index <= 5 &&
590	    !(i8k_hwmon_flags & I8K_HWMON_HAVE_FAN1))
591		return 0;
592	if (index >= 6 && index <= 7 &&
593	    !(i8k_hwmon_flags & I8K_HWMON_HAVE_FAN2))
594		return 0;
595
596	return attr->mode;
597}
598
599static const struct attribute_group i8k_group = {
600	.attrs = i8k_attrs,
601	.is_visible = i8k_is_visible,
602};
603__ATTRIBUTE_GROUPS(i8k);
604
605static int __init i8k_init_hwmon(void)
606{
607	int err;
608
609	i8k_hwmon_flags = 0;
610
611	/* CPU temperature attributes, if temperature reading is OK */
612	err = i8k_get_temp(0);
613	if (err >= 0)
614		i8k_hwmon_flags |= I8K_HWMON_HAVE_TEMP1;
615	/* check for additional temperature sensors */
616	err = i8k_get_temp(1);
617	if (err >= 0)
618		i8k_hwmon_flags |= I8K_HWMON_HAVE_TEMP2;
619	err = i8k_get_temp(2);
620	if (err >= 0)
621		i8k_hwmon_flags |= I8K_HWMON_HAVE_TEMP3;
622	err = i8k_get_temp(3);
623	if (err >= 0)
624		i8k_hwmon_flags |= I8K_HWMON_HAVE_TEMP4;
625
626	/* Left fan attributes, if left fan is present */
627	err = i8k_get_fan_status(I8K_FAN_LEFT);
628	if (err >= 0)
629		i8k_hwmon_flags |= I8K_HWMON_HAVE_FAN1;
630
631	/* Right fan attributes, if right fan is present */
632	err = i8k_get_fan_status(I8K_FAN_RIGHT);
633	if (err >= 0)
634		i8k_hwmon_flags |= I8K_HWMON_HAVE_FAN2;
635
636	i8k_hwmon_dev = hwmon_device_register_with_groups(NULL, "i8k", NULL,
637							  i8k_groups);
638	if (IS_ERR(i8k_hwmon_dev)) {
639		err = PTR_ERR(i8k_hwmon_dev);
640		i8k_hwmon_dev = NULL;
641		pr_err("hwmon registration failed (%d)\n", err);
642		return err;
643	}
644	return 0;
645}
646
647struct i8k_config_data {
648	int fan_mult;
649	int fan_max;
650};
651
652enum i8k_configs {
653	DELL_LATITUDE_D520,
654	DELL_LATITUDE_E6540,
655	DELL_PRECISION_490,
656	DELL_STUDIO,
657	DELL_XPS_M140,
658};
659
660static const struct i8k_config_data i8k_config_data[] = {
661	[DELL_LATITUDE_D520] = {
662		.fan_mult = 1,
663		.fan_max = I8K_FAN_TURBO,
664	},
665	[DELL_LATITUDE_E6540] = {
666		.fan_mult = 1,
667		.fan_max = I8K_FAN_HIGH,
668	},
669	[DELL_PRECISION_490] = {
670		.fan_mult = 1,
671		.fan_max = I8K_FAN_TURBO,
672	},
673	[DELL_STUDIO] = {
674		.fan_mult = 1,
675		.fan_max = I8K_FAN_HIGH,
676	},
677	[DELL_XPS_M140] = {
678		.fan_mult = 1,
679		.fan_max = I8K_FAN_HIGH,
680	},
681};
682
683static struct dmi_system_id i8k_dmi_table[] __initdata = {
684	{
685		.ident = "Dell Inspiron",
686		.matches = {
687			DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer"),
688			DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron"),
689		},
690	},
691	{
692		.ident = "Dell Latitude",
693		.matches = {
694			DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer"),
695			DMI_MATCH(DMI_PRODUCT_NAME, "Latitude"),
696		},
697	},
698	{
699		.ident = "Dell Inspiron 2",
700		.matches = {
701			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
702			DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron"),
703		},
704	},
705	{
706		.ident = "Dell Latitude D520",
707		.matches = {
708			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
709			DMI_MATCH(DMI_PRODUCT_NAME, "Latitude D520"),
710		},
711		.driver_data = (void *)&i8k_config_data[DELL_LATITUDE_D520],
712	},
713	{
714		.ident = "Dell Latitude E6540",
715		.matches = {
716			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
717			DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6540"),
718		},
719		.driver_data = (void *)&i8k_config_data[DELL_LATITUDE_E6540],
720	},
721	{
722		.ident = "Dell Latitude 2",
723		.matches = {
724			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
725			DMI_MATCH(DMI_PRODUCT_NAME, "Latitude"),
726		},
727	},
728	{	/* UK Inspiron 6400  */
729		.ident = "Dell Inspiron 3",
730		.matches = {
731			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
732			DMI_MATCH(DMI_PRODUCT_NAME, "MM061"),
733		},
734	},
735	{
736		.ident = "Dell Inspiron 3",
737		.matches = {
738			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
739			DMI_MATCH(DMI_PRODUCT_NAME, "MP061"),
740		},
741	},
742	{
743		.ident = "Dell Precision 490",
744		.matches = {
745			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
746			DMI_MATCH(DMI_PRODUCT_NAME,
747				  "Precision WorkStation 490"),
748		},
749		.driver_data = (void *)&i8k_config_data[DELL_PRECISION_490],
750	},
751	{
752		.ident = "Dell Precision",
753		.matches = {
754			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
755			DMI_MATCH(DMI_PRODUCT_NAME, "Precision"),
756		},
757	},
758	{
759		.ident = "Dell Vostro",
760		.matches = {
761			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
762			DMI_MATCH(DMI_PRODUCT_NAME, "Vostro"),
763		},
764	},
765	{
766		.ident = "Dell XPS421",
767		.matches = {
768			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
769			DMI_MATCH(DMI_PRODUCT_NAME, "XPS L421X"),
770		},
771	},
772	{
773		.ident = "Dell Studio",
774		.matches = {
775			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
776			DMI_MATCH(DMI_PRODUCT_NAME, "Studio"),
777		},
778		.driver_data = (void *)&i8k_config_data[DELL_STUDIO],
779	},
780	{
781		.ident = "Dell XPS M140",
782		.matches = {
783			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
784			DMI_MATCH(DMI_PRODUCT_NAME, "MXC051"),
785		},
786		.driver_data = (void *)&i8k_config_data[DELL_XPS_M140],
787	},
788	{ }
789};
790
791/*
792 * Probe for the presence of a supported laptop.
793 */
794static int __init i8k_probe(void)
795{
796	const struct dmi_system_id *id;
797
798	/*
799	 * Get DMI information
800	 */
801	if (!dmi_check_system(i8k_dmi_table)) {
802		if (!ignore_dmi && !force)
803			return -ENODEV;
804
805		pr_info("not running on a supported Dell system.\n");
806		pr_info("vendor=%s, model=%s, version=%s\n",
807			i8k_get_dmi_data(DMI_SYS_VENDOR),
808			i8k_get_dmi_data(DMI_PRODUCT_NAME),
809			i8k_get_dmi_data(DMI_BIOS_VERSION));
810	}
811
812	strlcpy(bios_version, i8k_get_dmi_data(DMI_BIOS_VERSION),
813		sizeof(bios_version));
814
815	/*
816	 * Get SMM Dell signature
817	 */
818	if (i8k_get_dell_signature(I8K_SMM_GET_DELL_SIG1) &&
819	    i8k_get_dell_signature(I8K_SMM_GET_DELL_SIG2)) {
820		pr_err("unable to get SMM Dell signature\n");
821		if (!force)
822			return -ENODEV;
823	}
824
825	i8k_fan_mult = fan_mult;
826	i8k_fan_max = fan_max ? : I8K_FAN_HIGH;	/* Must not be 0 */
827	id = dmi_first_match(i8k_dmi_table);
828	if (id && id->driver_data) {
829		const struct i8k_config_data *conf = id->driver_data;
830
831		if (fan_mult == I8K_FAN_MULT && conf->fan_mult)
832			i8k_fan_mult = conf->fan_mult;
833		if (fan_max == I8K_FAN_HIGH && conf->fan_max)
834			i8k_fan_max = conf->fan_max;
835	}
836	i8k_pwm_mult = DIV_ROUND_UP(255, i8k_fan_max);
837
838	return 0;
839}
840
841static int __init i8k_init(void)
842{
843	struct proc_dir_entry *proc_i8k;
844	int err;
845
846	/* Are we running on an supported laptop? */
847	if (i8k_probe())
848		return -ENODEV;
849
850	/* Register the proc entry */
851	proc_i8k = proc_create("i8k", 0, NULL, &i8k_fops);
852	if (!proc_i8k)
853		return -ENOENT;
854
855	err = i8k_init_hwmon();
856	if (err)
857		goto exit_remove_proc;
858
859	return 0;
860
861 exit_remove_proc:
862	remove_proc_entry("i8k", NULL);
863	return err;
864}
865
866static void __exit i8k_exit(void)
867{
868	hwmon_device_unregister(i8k_hwmon_dev);
869	remove_proc_entry("i8k", NULL);
870}
871
872module_init(i8k_init);
873module_exit(i8k_exit);
874