d6e8a267d3a60aabcd74a4cf32c7c11e0a98749a
[linux-2.6-block.git] / drivers / char / i8k.c
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, 2014  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/delay.h>
24 #include <linux/module.h>
25 #include <linux/types.h>
26 #include <linux/init.h>
27 #include <linux/proc_fs.h>
28 #include <linux/seq_file.h>
29 #include <linux/dmi.h>
30 #include <linux/capability.h>
31 #include <linux/mutex.h>
32 #include <linux/hwmon.h>
33 #include <linux/hwmon-sysfs.h>
34 #include <linux/uaccess.h>
35 #include <linux/io.h>
36 #include <linux/sched.h>
37
38 #include <linux/i8k.h>
39
40 #define I8K_SMM_FN_STATUS       0x0025
41 #define I8K_SMM_POWER_STATUS    0x0069
42 #define I8K_SMM_SET_FAN         0x01a3
43 #define I8K_SMM_GET_FAN         0x00a3
44 #define I8K_SMM_GET_SPEED       0x02a3
45 #define I8K_SMM_GET_TEMP        0x10a3
46 #define I8K_SMM_GET_TEMP_TYPE   0x11a3
47 #define I8K_SMM_GET_DELL_SIG1   0xfea3
48 #define I8K_SMM_GET_DELL_SIG2   0xffa3
49
50 #define I8K_FAN_MULT            30
51 #define I8K_MAX_TEMP            127
52
53 #define I8K_FN_NONE             0x00
54 #define I8K_FN_UP               0x01
55 #define I8K_FN_DOWN             0x02
56 #define I8K_FN_MUTE             0x04
57 #define I8K_FN_MASK             0x07
58 #define I8K_FN_SHIFT            8
59
60 #define I8K_POWER_AC            0x05
61 #define I8K_POWER_BATTERY       0x01
62
63 static DEFINE_MUTEX(i8k_mutex);
64 static char bios_version[4];
65 static struct device *i8k_hwmon_dev;
66 static u32 i8k_hwmon_flags;
67 static uint i8k_fan_mult;
68 static uint i8k_pwm_mult;
69 static uint 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
78 MODULE_AUTHOR("Massimo Dal Zotto (dz@debian.org)");
79 MODULE_DESCRIPTION("Driver for accessing SMM BIOS on Dell laptops");
80 MODULE_LICENSE("GPL");
81
82 static bool force;
83 module_param(force, bool, 0);
84 MODULE_PARM_DESC(force, "Force loading without checking for supported models");
85
86 static bool ignore_dmi;
87 module_param(ignore_dmi, bool, 0);
88 MODULE_PARM_DESC(ignore_dmi, "Continue probing hardware even if DMI data does not match");
89
90 static bool restricted;
91 module_param(restricted, bool, 0);
92 MODULE_PARM_DESC(restricted, "Allow fan control if SYS_ADMIN capability set");
93
94 static bool power_status;
95 module_param(power_status, bool, 0600);
96 MODULE_PARM_DESC(power_status, "Report power status in /proc/i8k");
97
98 static uint fan_mult = I8K_FAN_MULT;
99 module_param(fan_mult, uint, 0);
100 MODULE_PARM_DESC(fan_mult, "Factor to multiply fan speed with");
101
102 static uint fan_max = I8K_FAN_HIGH;
103 module_param(fan_max, uint, 0);
104 MODULE_PARM_DESC(fan_max, "Maximum configurable fan speed");
105
106 static int i8k_open_fs(struct inode *inode, struct file *file);
107 static long i8k_ioctl(struct file *, unsigned int, unsigned long);
108
109 static 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
118 struct 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
127 static 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  */
137 static 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
211 out:
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  */
220 static 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  */
244 static 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  */
259 static 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  */
270 static 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  */
281 static 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 static int i8k_get_temp_type(int sensor)
292 {
293         struct smm_regs regs = { .eax = I8K_SMM_GET_TEMP_TYPE, };
294
295         regs.ebx = sensor & 0xff;
296         return i8k_smm(&regs) ? : regs.eax & 0xff;
297 }
298
299 /*
300  * Read the cpu temperature.
301  */
302 static int _i8k_get_temp(int sensor)
303 {
304         struct smm_regs regs = {
305                 .eax = I8K_SMM_GET_TEMP,
306                 .ebx = sensor & 0xff,
307         };
308
309         return i8k_smm(&regs) ? : regs.eax & 0xff;
310 }
311
312 static int i8k_get_temp(int sensor)
313 {
314         int temp = _i8k_get_temp(sensor);
315
316         /*
317          * Sometimes the temperature sensor returns 0x99, which is out of range.
318          * In this case we retry (once) before returning an error.
319          # 1003655137 00000058 00005a4b
320          # 1003655138 00000099 00003a80 <--- 0x99 = 153 degrees
321          # 1003655139 00000054 00005c52
322          */
323         if (temp == 0x99) {
324                 msleep(100);
325                 temp = _i8k_get_temp(sensor);
326         }
327         /*
328          * Return -ENODATA for all invalid temperatures.
329          *
330          * Known instances are the 0x99 value as seen above as well as
331          * 0xc1 (193), which may be returned when trying to read the GPU
332          * temperature if the system supports a GPU and it is currently
333          * turned off.
334          */
335         if (temp > I8K_MAX_TEMP)
336                 return -ENODATA;
337
338         return temp;
339 }
340
341 static int i8k_get_dell_signature(int req_fn)
342 {
343         struct smm_regs regs = { .eax = req_fn, };
344         int rc;
345
346         rc = i8k_smm(&regs);
347         if (rc < 0)
348                 return rc;
349
350         return regs.eax == 1145651527 && regs.edx == 1145392204 ? 0 : -1;
351 }
352
353 static int
354 i8k_ioctl_unlocked(struct file *fp, unsigned int cmd, unsigned long arg)
355 {
356         int val = 0;
357         int speed;
358         unsigned char buff[16];
359         int __user *argp = (int __user *)arg;
360
361         if (!argp)
362                 return -EINVAL;
363
364         switch (cmd) {
365         case I8K_BIOS_VERSION:
366                 val = (bios_version[0] << 16) |
367                                 (bios_version[1] << 8) | bios_version[2];
368                 break;
369
370         case I8K_MACHINE_ID:
371                 memset(buff, 0, 16);
372                 strlcpy(buff, i8k_get_dmi_data(DMI_PRODUCT_SERIAL),
373                         sizeof(buff));
374                 break;
375
376         case I8K_FN_STATUS:
377                 val = i8k_get_fn_status();
378                 break;
379
380         case I8K_POWER_STATUS:
381                 val = i8k_get_power_status();
382                 break;
383
384         case I8K_GET_TEMP:
385                 val = i8k_get_temp(0);
386                 break;
387
388         case I8K_GET_SPEED:
389                 if (copy_from_user(&val, argp, sizeof(int)))
390                         return -EFAULT;
391
392                 val = i8k_get_fan_speed(val);
393                 break;
394
395         case I8K_GET_FAN:
396                 if (copy_from_user(&val, argp, sizeof(int)))
397                         return -EFAULT;
398
399                 val = i8k_get_fan_status(val);
400                 break;
401
402         case I8K_SET_FAN:
403                 if (restricted && !capable(CAP_SYS_ADMIN))
404                         return -EPERM;
405
406                 if (copy_from_user(&val, argp, sizeof(int)))
407                         return -EFAULT;
408
409                 if (copy_from_user(&speed, argp + 1, sizeof(int)))
410                         return -EFAULT;
411
412                 val = i8k_set_fan(val, speed);
413                 break;
414
415         default:
416                 return -EINVAL;
417         }
418
419         if (val < 0)
420                 return val;
421
422         switch (cmd) {
423         case I8K_BIOS_VERSION:
424                 if (copy_to_user(argp, &val, 4))
425                         return -EFAULT;
426
427                 break;
428         case I8K_MACHINE_ID:
429                 if (copy_to_user(argp, buff, 16))
430                         return -EFAULT;
431
432                 break;
433         default:
434                 if (copy_to_user(argp, &val, sizeof(int)))
435                         return -EFAULT;
436
437                 break;
438         }
439
440         return 0;
441 }
442
443 static long i8k_ioctl(struct file *fp, unsigned int cmd, unsigned long arg)
444 {
445         long ret;
446
447         mutex_lock(&i8k_mutex);
448         ret = i8k_ioctl_unlocked(fp, cmd, arg);
449         mutex_unlock(&i8k_mutex);
450
451         return ret;
452 }
453
454 /*
455  * Print the information for /proc/i8k.
456  */
457 static int i8k_proc_show(struct seq_file *seq, void *offset)
458 {
459         int fn_key, cpu_temp, ac_power;
460         int left_fan, right_fan, left_speed, right_speed;
461
462         cpu_temp        = i8k_get_temp(0);                      /* 11100 Âµs */
463         left_fan        = i8k_get_fan_status(I8K_FAN_LEFT);     /*   580 Âµs */
464         right_fan       = i8k_get_fan_status(I8K_FAN_RIGHT);    /*   580 Âµs */
465         left_speed      = i8k_get_fan_speed(I8K_FAN_LEFT);      /*   580 Âµs */
466         right_speed     = i8k_get_fan_speed(I8K_FAN_RIGHT);     /*   580 Âµs */
467         fn_key          = i8k_get_fn_status();                  /*   750 Âµs */
468         if (power_status)
469                 ac_power = i8k_get_power_status();              /* 14700 Âµs */
470         else
471                 ac_power = -1;
472
473         /*
474          * Info:
475          *
476          * 1)  Format version (this will change if format changes)
477          * 2)  BIOS version
478          * 3)  BIOS machine ID
479          * 4)  Cpu temperature
480          * 5)  Left fan status
481          * 6)  Right fan status
482          * 7)  Left fan speed
483          * 8)  Right fan speed
484          * 9)  AC power
485          * 10) Fn Key status
486          */
487         return seq_printf(seq, "%s %s %s %d %d %d %d %d %d %d\n",
488                           I8K_PROC_FMT,
489                           bios_version,
490                           i8k_get_dmi_data(DMI_PRODUCT_SERIAL),
491                           cpu_temp,
492                           left_fan, right_fan, left_speed, right_speed,
493                           ac_power, fn_key);
494 }
495
496 static int i8k_open_fs(struct inode *inode, struct file *file)
497 {
498         return single_open(file, i8k_proc_show, NULL);
499 }
500
501
502 /*
503  * Hwmon interface
504  */
505
506 static ssize_t i8k_hwmon_show_temp_label(struct device *dev,
507                                          struct device_attribute *devattr,
508                                          char *buf)
509 {
510         static const char * const labels[] = {
511                 "CPU",
512                 "GPU",
513                 "SODIMM",
514                 "Other",
515                 "Ambient",
516                 "Other",
517         };
518         int index = to_sensor_dev_attr(devattr)->index;
519         int type;
520
521         type = i8k_get_temp_type(index);
522         if (type < 0)
523                 return type;
524         if (type >= ARRAY_SIZE(labels))
525                 type = ARRAY_SIZE(labels) - 1;
526         return sprintf(buf, "%s\n", labels[type]);
527 }
528
529 static ssize_t i8k_hwmon_show_temp(struct device *dev,
530                                    struct device_attribute *devattr,
531                                    char *buf)
532 {
533         int index = to_sensor_dev_attr(devattr)->index;
534         int temp;
535
536         temp = i8k_get_temp(index);
537         if (temp < 0)
538                 return temp;
539         return sprintf(buf, "%d\n", temp * 1000);
540 }
541
542 static ssize_t i8k_hwmon_show_fan(struct device *dev,
543                                   struct device_attribute *devattr,
544                                   char *buf)
545 {
546         int index = to_sensor_dev_attr(devattr)->index;
547         int fan_speed;
548
549         fan_speed = i8k_get_fan_speed(index);
550         if (fan_speed < 0)
551                 return fan_speed;
552         return sprintf(buf, "%d\n", fan_speed);
553 }
554
555 static ssize_t i8k_hwmon_show_pwm(struct device *dev,
556                                   struct device_attribute *devattr,
557                                   char *buf)
558 {
559         int index = to_sensor_dev_attr(devattr)->index;
560         int status;
561
562         status = i8k_get_fan_status(index);
563         if (status < 0)
564                 return -EIO;
565         return sprintf(buf, "%d\n", clamp_val(status * i8k_pwm_mult, 0, 255));
566 }
567
568 static ssize_t i8k_hwmon_set_pwm(struct device *dev,
569                                  struct device_attribute *attr,
570                                  const char *buf, size_t count)
571 {
572         int index = to_sensor_dev_attr(attr)->index;
573         unsigned long val;
574         int err;
575
576         err = kstrtoul(buf, 10, &val);
577         if (err)
578                 return err;
579         val = clamp_val(DIV_ROUND_CLOSEST(val, i8k_pwm_mult), 0, i8k_fan_max);
580
581         mutex_lock(&i8k_mutex);
582         err = i8k_set_fan(index, val);
583         mutex_unlock(&i8k_mutex);
584
585         return err < 0 ? -EIO : count;
586 }
587
588 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, i8k_hwmon_show_temp, NULL, 0);
589 static SENSOR_DEVICE_ATTR(temp1_label, S_IRUGO, i8k_hwmon_show_temp_label, NULL,
590                           0);
591 static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, i8k_hwmon_show_temp, NULL, 1);
592 static SENSOR_DEVICE_ATTR(temp2_label, S_IRUGO, i8k_hwmon_show_temp_label, NULL,
593                           1);
594 static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, i8k_hwmon_show_temp, NULL, 2);
595 static SENSOR_DEVICE_ATTR(temp3_label, S_IRUGO, i8k_hwmon_show_temp_label, NULL,
596                           2);
597 static SENSOR_DEVICE_ATTR(temp4_input, S_IRUGO, i8k_hwmon_show_temp, NULL, 3);
598 static SENSOR_DEVICE_ATTR(temp4_label, S_IRUGO, i8k_hwmon_show_temp_label, NULL,
599                           3);
600 static SENSOR_DEVICE_ATTR(fan1_input, S_IRUGO, i8k_hwmon_show_fan, NULL,
601                           I8K_FAN_LEFT);
602 static SENSOR_DEVICE_ATTR(pwm1, S_IRUGO | S_IWUSR, i8k_hwmon_show_pwm,
603                           i8k_hwmon_set_pwm, I8K_FAN_LEFT);
604 static SENSOR_DEVICE_ATTR(fan2_input, S_IRUGO, i8k_hwmon_show_fan, NULL,
605                           I8K_FAN_RIGHT);
606 static SENSOR_DEVICE_ATTR(pwm2, S_IRUGO | S_IWUSR, i8k_hwmon_show_pwm,
607                           i8k_hwmon_set_pwm, I8K_FAN_RIGHT);
608
609 static struct attribute *i8k_attrs[] = {
610         &sensor_dev_attr_temp1_input.dev_attr.attr,     /* 0 */
611         &sensor_dev_attr_temp1_label.dev_attr.attr,     /* 1 */
612         &sensor_dev_attr_temp2_input.dev_attr.attr,     /* 2 */
613         &sensor_dev_attr_temp2_label.dev_attr.attr,     /* 3 */
614         &sensor_dev_attr_temp3_input.dev_attr.attr,     /* 4 */
615         &sensor_dev_attr_temp3_label.dev_attr.attr,     /* 5 */
616         &sensor_dev_attr_temp4_input.dev_attr.attr,     /* 6 */
617         &sensor_dev_attr_temp4_label.dev_attr.attr,     /* 7 */
618         &sensor_dev_attr_fan1_input.dev_attr.attr,      /* 8 */
619         &sensor_dev_attr_pwm1.dev_attr.attr,            /* 9 */
620         &sensor_dev_attr_fan2_input.dev_attr.attr,      /* 10 */
621         &sensor_dev_attr_pwm2.dev_attr.attr,            /* 11 */
622         NULL
623 };
624
625 static umode_t i8k_is_visible(struct kobject *kobj, struct attribute *attr,
626                               int index)
627 {
628         if (index >= 0 && index <= 1 &&
629             !(i8k_hwmon_flags & I8K_HWMON_HAVE_TEMP1))
630                 return 0;
631         if (index >= 2 && index <= 3 &&
632             !(i8k_hwmon_flags & I8K_HWMON_HAVE_TEMP2))
633                 return 0;
634         if (index >= 4 && index <= 5 &&
635             !(i8k_hwmon_flags & I8K_HWMON_HAVE_TEMP3))
636                 return 0;
637         if (index >= 6 && index <= 7 &&
638             !(i8k_hwmon_flags & I8K_HWMON_HAVE_TEMP4))
639                 return 0;
640         if (index >= 8 && index <= 9 &&
641             !(i8k_hwmon_flags & I8K_HWMON_HAVE_FAN1))
642                 return 0;
643         if (index >= 10 && index <= 11 &&
644             !(i8k_hwmon_flags & I8K_HWMON_HAVE_FAN2))
645                 return 0;
646
647         return attr->mode;
648 }
649
650 static const struct attribute_group i8k_group = {
651         .attrs = i8k_attrs,
652         .is_visible = i8k_is_visible,
653 };
654 __ATTRIBUTE_GROUPS(i8k);
655
656 static int __init i8k_init_hwmon(void)
657 {
658         int err;
659
660         i8k_hwmon_flags = 0;
661
662         /* CPU temperature attributes, if temperature type is OK */
663         err = i8k_get_temp_type(0);
664         if (err >= 0)
665                 i8k_hwmon_flags |= I8K_HWMON_HAVE_TEMP1;
666         /* check for additional temperature sensors */
667         err = i8k_get_temp_type(1);
668         if (err >= 0)
669                 i8k_hwmon_flags |= I8K_HWMON_HAVE_TEMP2;
670         err = i8k_get_temp_type(2);
671         if (err >= 0)
672                 i8k_hwmon_flags |= I8K_HWMON_HAVE_TEMP3;
673         err = i8k_get_temp_type(3);
674         if (err >= 0)
675                 i8k_hwmon_flags |= I8K_HWMON_HAVE_TEMP4;
676
677         /* Left fan attributes, if left fan is present */
678         err = i8k_get_fan_status(I8K_FAN_LEFT);
679         if (err >= 0)
680                 i8k_hwmon_flags |= I8K_HWMON_HAVE_FAN1;
681
682         /* Right fan attributes, if right fan is present */
683         err = i8k_get_fan_status(I8K_FAN_RIGHT);
684         if (err >= 0)
685                 i8k_hwmon_flags |= I8K_HWMON_HAVE_FAN2;
686
687         i8k_hwmon_dev = hwmon_device_register_with_groups(NULL, "i8k", NULL,
688                                                           i8k_groups);
689         if (IS_ERR(i8k_hwmon_dev)) {
690                 err = PTR_ERR(i8k_hwmon_dev);
691                 i8k_hwmon_dev = NULL;
692                 pr_err("hwmon registration failed (%d)\n", err);
693                 return err;
694         }
695         return 0;
696 }
697
698 struct i8k_config_data {
699         uint fan_mult;
700         uint fan_max;
701 };
702
703 enum i8k_configs {
704         DELL_LATITUDE_D520,
705         DELL_LATITUDE_E6540,
706         DELL_PRECISION_490,
707         DELL_STUDIO,
708         DELL_XPS,
709 };
710
711 static const struct i8k_config_data i8k_config_data[] = {
712         [DELL_LATITUDE_D520] = {
713                 .fan_mult = 1,
714                 .fan_max = I8K_FAN_TURBO,
715         },
716         [DELL_LATITUDE_E6540] = {
717                 .fan_mult = 1,
718                 .fan_max = I8K_FAN_HIGH,
719         },
720         [DELL_PRECISION_490] = {
721                 .fan_mult = 1,
722                 .fan_max = I8K_FAN_TURBO,
723         },
724         [DELL_STUDIO] = {
725                 .fan_mult = 1,
726                 .fan_max = I8K_FAN_HIGH,
727         },
728         [DELL_XPS] = {
729                 .fan_mult = 1,
730                 .fan_max = I8K_FAN_HIGH,
731         },
732 };
733
734 static struct dmi_system_id i8k_dmi_table[] __initdata = {
735         {
736                 .ident = "Dell Inspiron",
737                 .matches = {
738                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer"),
739                         DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron"),
740                 },
741         },
742         {
743                 .ident = "Dell Latitude",
744                 .matches = {
745                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer"),
746                         DMI_MATCH(DMI_PRODUCT_NAME, "Latitude"),
747                 },
748         },
749         {
750                 .ident = "Dell Inspiron 2",
751                 .matches = {
752                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
753                         DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron"),
754                 },
755         },
756         {
757                 .ident = "Dell Latitude D520",
758                 .matches = {
759                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
760                         DMI_MATCH(DMI_PRODUCT_NAME, "Latitude D520"),
761                 },
762                 .driver_data = (void *)&i8k_config_data[DELL_LATITUDE_D520],
763         },
764         {
765                 .ident = "Dell Latitude E6440",
766                 .matches = {
767                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
768                         DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6440"),
769                 },
770                 .driver_data = (void *)&i8k_config_data[DELL_LATITUDE_E6540],
771         },
772         {
773                 .ident = "Dell Latitude E6540",
774                 .matches = {
775                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
776                         DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6540"),
777                 },
778                 .driver_data = (void *)&i8k_config_data[DELL_LATITUDE_E6540],
779         },
780         {
781                 .ident = "Dell Latitude 2",
782                 .matches = {
783                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
784                         DMI_MATCH(DMI_PRODUCT_NAME, "Latitude"),
785                 },
786         },
787         {       /* UK Inspiron 6400  */
788                 .ident = "Dell Inspiron 3",
789                 .matches = {
790                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
791                         DMI_MATCH(DMI_PRODUCT_NAME, "MM061"),
792                 },
793         },
794         {
795                 .ident = "Dell Inspiron 3",
796                 .matches = {
797                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
798                         DMI_MATCH(DMI_PRODUCT_NAME, "MP061"),
799                 },
800         },
801         {
802                 .ident = "Dell Precision 490",
803                 .matches = {
804                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
805                         DMI_MATCH(DMI_PRODUCT_NAME,
806                                   "Precision WorkStation 490"),
807                 },
808                 .driver_data = (void *)&i8k_config_data[DELL_PRECISION_490],
809         },
810         {
811                 .ident = "Dell Precision",
812                 .matches = {
813                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
814                         DMI_MATCH(DMI_PRODUCT_NAME, "Precision"),
815                 },
816         },
817         {
818                 .ident = "Dell Vostro",
819                 .matches = {
820                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
821                         DMI_MATCH(DMI_PRODUCT_NAME, "Vostro"),
822                 },
823         },
824         {
825                 .ident = "Dell XPS421",
826                 .matches = {
827                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
828                         DMI_MATCH(DMI_PRODUCT_NAME, "XPS L421X"),
829                 },
830         },
831         {
832                 .ident = "Dell Studio",
833                 .matches = {
834                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
835                         DMI_MATCH(DMI_PRODUCT_NAME, "Studio"),
836                 },
837                 .driver_data = (void *)&i8k_config_data[DELL_STUDIO],
838         },
839         {
840                 .ident = "Dell XPS 13",
841                 .matches = {
842                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
843                         DMI_MATCH(DMI_PRODUCT_NAME, "XPS13"),
844                 },
845                 .driver_data = (void *)&i8k_config_data[DELL_XPS],
846         },
847         {
848                 .ident = "Dell XPS M140",
849                 .matches = {
850                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
851                         DMI_MATCH(DMI_PRODUCT_NAME, "MXC051"),
852                 },
853                 .driver_data = (void *)&i8k_config_data[DELL_XPS],
854         },
855         { }
856 };
857
858 MODULE_DEVICE_TABLE(dmi, i8k_dmi_table);
859
860 /*
861  * Probe for the presence of a supported laptop.
862  */
863 static int __init i8k_probe(void)
864 {
865         const struct dmi_system_id *id;
866
867         /*
868          * Get DMI information
869          */
870         if (!dmi_check_system(i8k_dmi_table)) {
871                 if (!ignore_dmi && !force)
872                         return -ENODEV;
873
874                 pr_info("not running on a supported Dell system.\n");
875                 pr_info("vendor=%s, model=%s, version=%s\n",
876                         i8k_get_dmi_data(DMI_SYS_VENDOR),
877                         i8k_get_dmi_data(DMI_PRODUCT_NAME),
878                         i8k_get_dmi_data(DMI_BIOS_VERSION));
879         }
880
881         strlcpy(bios_version, i8k_get_dmi_data(DMI_BIOS_VERSION),
882                 sizeof(bios_version));
883
884         /*
885          * Get SMM Dell signature
886          */
887         if (i8k_get_dell_signature(I8K_SMM_GET_DELL_SIG1) &&
888             i8k_get_dell_signature(I8K_SMM_GET_DELL_SIG2)) {
889                 pr_err("unable to get SMM Dell signature\n");
890                 if (!force)
891                         return -ENODEV;
892         }
893
894         i8k_fan_mult = fan_mult;
895         i8k_fan_max = fan_max ? : I8K_FAN_HIGH; /* Must not be 0 */
896         id = dmi_first_match(i8k_dmi_table);
897         if (id && id->driver_data) {
898                 const struct i8k_config_data *conf = id->driver_data;
899
900                 if (fan_mult == I8K_FAN_MULT && conf->fan_mult)
901                         i8k_fan_mult = conf->fan_mult;
902                 if (fan_max == I8K_FAN_HIGH && conf->fan_max)
903                         i8k_fan_max = conf->fan_max;
904         }
905         i8k_pwm_mult = DIV_ROUND_UP(255, i8k_fan_max);
906
907         return 0;
908 }
909
910 static int __init i8k_init(void)
911 {
912         struct proc_dir_entry *proc_i8k;
913         int err;
914
915         /* Are we running on an supported laptop? */
916         if (i8k_probe())
917                 return -ENODEV;
918
919         /* Register the proc entry */
920         proc_i8k = proc_create("i8k", 0, NULL, &i8k_fops);
921         if (!proc_i8k)
922                 return -ENOENT;
923
924         err = i8k_init_hwmon();
925         if (err)
926                 goto exit_remove_proc;
927
928         return 0;
929
930  exit_remove_proc:
931         remove_proc_entry("i8k", NULL);
932         return err;
933 }
934
935 static void __exit i8k_exit(void)
936 {
937         hwmon_device_unregister(i8k_hwmon_dev);
938         remove_proc_entry("i8k", NULL);
939 }
940
941 module_init(i8k_init);
942 module_exit(i8k_exit);