40cc0cf2ded639f6b4e3f28cfb1b093660c19ae1
[linux-2.6.git] / drivers / char / i8k.c
1 /*
2  * i8k.c -- Linux driver for accessing the SMM BIOS on Dell laptops.
3  *          See http://www.debian.org/~dz/i8k/ for more information
4  *          and for latest version of this driver.
5  *
6  * Copyright (C) 2001  Massimo Dal Zotto <dz@debian.org>
7  *
8  * Hwmon integration:
9  * Copyright (C) 2011  Jean Delvare <khali@linux-fr.org>
10  *
11  * This program is free software; you can redistribute it and/or modify it
12  * under the terms of the GNU General Public License as published by the
13  * Free Software Foundation; either version 2, or (at your option) any
14  * later version.
15  *
16  * This program is distributed in the hope that it will be useful, but
17  * WITHOUT ANY WARRANTY; without even the implied warranty of
18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
19  * General Public License for more details.
20  */
21
22 #include <linux/module.h>
23 #include <linux/types.h>
24 #include <linux/init.h>
25 #include <linux/proc_fs.h>
26 #include <linux/seq_file.h>
27 #include <linux/dmi.h>
28 #include <linux/capability.h>
29 #include <linux/mutex.h>
30 #include <linux/hwmon.h>
31 #include <linux/hwmon-sysfs.h>
32 #include <asm/uaccess.h>
33 #include <asm/io.h>
34
35 #include <linux/i8k.h>
36
37 #define I8K_VERSION             "1.14 21/02/2005"
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 #define I8K_SMM_BIOS_VERSION    0x00a6
48
49 #define I8K_FAN_MULT            30
50 #define I8K_MAX_TEMP            127
51
52 #define I8K_FN_NONE             0x00
53 #define I8K_FN_UP               0x01
54 #define I8K_FN_DOWN             0x02
55 #define I8K_FN_MUTE             0x04
56 #define I8K_FN_MASK             0x07
57 #define I8K_FN_SHIFT            8
58
59 #define I8K_POWER_AC            0x05
60 #define I8K_POWER_BATTERY       0x01
61
62 #define I8K_TEMPERATURE_BUG     1
63
64 static DEFINE_MUTEX(i8k_mutex);
65 static char bios_version[4];
66 static struct device *i8k_hwmon_dev;
67
68 MODULE_AUTHOR("Massimo Dal Zotto (dz@debian.org)");
69 MODULE_DESCRIPTION("Driver for accessing SMM BIOS on Dell laptops");
70 MODULE_LICENSE("GPL");
71
72 static bool force;
73 module_param(force, bool, 0);
74 MODULE_PARM_DESC(force, "Force loading without checking for supported models");
75
76 static bool ignore_dmi;
77 module_param(ignore_dmi, bool, 0);
78 MODULE_PARM_DESC(ignore_dmi, "Continue probing hardware even if DMI data does not match");
79
80 static bool restricted;
81 module_param(restricted, bool, 0);
82 MODULE_PARM_DESC(restricted, "Allow fan control if SYS_ADMIN capability set");
83
84 static bool power_status;
85 module_param(power_status, bool, 0600);
86 MODULE_PARM_DESC(power_status, "Report power status in /proc/i8k");
87
88 static int fan_mult = I8K_FAN_MULT;
89 module_param(fan_mult, int, 0);
90 MODULE_PARM_DESC(fan_mult, "Factor to multiply fan speed with");
91
92 static int i8k_open_fs(struct inode *inode, struct file *file);
93 static long i8k_ioctl(struct file *, unsigned int, unsigned long);
94
95 static const struct file_operations i8k_fops = {
96         .owner          = THIS_MODULE,
97         .open           = i8k_open_fs,
98         .read           = seq_read,
99         .llseek         = seq_lseek,
100         .release        = single_release,
101         .unlocked_ioctl = i8k_ioctl,
102 };
103
104 struct smm_regs {
105         unsigned int eax;
106         unsigned int ebx __attribute__ ((packed));
107         unsigned int ecx __attribute__ ((packed));
108         unsigned int edx __attribute__ ((packed));
109         unsigned int esi __attribute__ ((packed));
110         unsigned int edi __attribute__ ((packed));
111 };
112
113 static inline const char *i8k_get_dmi_data(int field)
114 {
115         const char *dmi_data = dmi_get_system_info(field);
116
117         return dmi_data && *dmi_data ? dmi_data : "?";
118 }
119
120 /*
121  * Call the System Management Mode BIOS. Code provided by Jonathan Buzzard.
122  */
123 static int i8k_smm(struct smm_regs *regs)
124 {
125         int rc;
126         int eax = regs->eax;
127
128 #if defined(CONFIG_X86_64)
129         asm volatile("pushq %%rax\n\t"
130                 "movl 0(%%rax),%%edx\n\t"
131                 "pushq %%rdx\n\t"
132                 "movl 4(%%rax),%%ebx\n\t"
133                 "movl 8(%%rax),%%ecx\n\t"
134                 "movl 12(%%rax),%%edx\n\t"
135                 "movl 16(%%rax),%%esi\n\t"
136                 "movl 20(%%rax),%%edi\n\t"
137                 "popq %%rax\n\t"
138                 "out %%al,$0xb2\n\t"
139                 "out %%al,$0x84\n\t"
140                 "xchgq %%rax,(%%rsp)\n\t"
141                 "movl %%ebx,4(%%rax)\n\t"
142                 "movl %%ecx,8(%%rax)\n\t"
143                 "movl %%edx,12(%%rax)\n\t"
144                 "movl %%esi,16(%%rax)\n\t"
145                 "movl %%edi,20(%%rax)\n\t"
146                 "popq %%rdx\n\t"
147                 "movl %%edx,0(%%rax)\n\t"
148                 "pushfq\n\t"
149                 "popq %%rax\n\t"
150                 "andl $1,%%eax\n"
151                 :"=a"(rc)
152                 :    "a"(regs)
153                 :    "%ebx", "%ecx", "%edx", "%esi", "%edi", "memory");
154 #else
155         asm volatile("pushl %%eax\n\t"
156             "movl 0(%%eax),%%edx\n\t"
157             "push %%edx\n\t"
158             "movl 4(%%eax),%%ebx\n\t"
159             "movl 8(%%eax),%%ecx\n\t"
160             "movl 12(%%eax),%%edx\n\t"
161             "movl 16(%%eax),%%esi\n\t"
162             "movl 20(%%eax),%%edi\n\t"
163             "popl %%eax\n\t"
164             "out %%al,$0xb2\n\t"
165             "out %%al,$0x84\n\t"
166             "xchgl %%eax,(%%esp)\n\t"
167             "movl %%ebx,4(%%eax)\n\t"
168             "movl %%ecx,8(%%eax)\n\t"
169             "movl %%edx,12(%%eax)\n\t"
170             "movl %%esi,16(%%eax)\n\t"
171             "movl %%edi,20(%%eax)\n\t"
172             "popl %%edx\n\t"
173             "movl %%edx,0(%%eax)\n\t"
174             "lahf\n\t"
175             "shrl $8,%%eax\n\t"
176             "andl $1,%%eax\n"
177             :"=a"(rc)
178             :    "a"(regs)
179             :    "%ebx", "%ecx", "%edx", "%esi", "%edi", "memory");
180 #endif
181         if (rc != 0 || (regs->eax & 0xffff) == 0xffff || regs->eax == eax)
182                 return -EINVAL;
183
184         return 0;
185 }
186
187 /*
188  * Read the bios version. Return the version as an integer corresponding
189  * to the ascii value, for example "A17" is returned as 0x00413137.
190  */
191 static int i8k_get_bios_version(void)
192 {
193         struct smm_regs regs = { .eax = I8K_SMM_BIOS_VERSION, };
194
195         return i8k_smm(&regs) ? : regs.eax;
196 }
197
198 /*
199  * Read the Fn key status.
200  */
201 static int i8k_get_fn_status(void)
202 {
203         struct smm_regs regs = { .eax = I8K_SMM_FN_STATUS, };
204         int rc;
205
206         if ((rc = i8k_smm(&regs)) < 0)
207                 return rc;
208
209         switch ((regs.eax >> I8K_FN_SHIFT) & I8K_FN_MASK) {
210         case I8K_FN_UP:
211                 return I8K_VOL_UP;
212         case I8K_FN_DOWN:
213                 return I8K_VOL_DOWN;
214         case I8K_FN_MUTE:
215                 return I8K_VOL_MUTE;
216         default:
217                 return 0;
218         }
219 }
220
221 /*
222  * Read the power status.
223  */
224 static int i8k_get_power_status(void)
225 {
226         struct smm_regs regs = { .eax = I8K_SMM_POWER_STATUS, };
227         int rc;
228
229         if ((rc = i8k_smm(&regs)) < 0)
230                 return rc;
231
232         return (regs.eax & 0xff) == I8K_POWER_AC ? I8K_AC : I8K_BATTERY;
233 }
234
235 /*
236  * Read the fan status.
237  */
238 static int i8k_get_fan_status(int fan)
239 {
240         struct smm_regs regs = { .eax = I8K_SMM_GET_FAN, };
241
242         regs.ebx = fan & 0xff;
243         return i8k_smm(&regs) ? : regs.eax & 0xff;
244 }
245
246 /*
247  * Read the fan speed in RPM.
248  */
249 static int i8k_get_fan_speed(int fan)
250 {
251         struct smm_regs regs = { .eax = I8K_SMM_GET_SPEED, };
252
253         regs.ebx = fan & 0xff;
254         return i8k_smm(&regs) ? : (regs.eax & 0xffff) * fan_mult;
255 }
256
257 /*
258  * Set the fan speed (off, low, high). Returns the new fan status.
259  */
260 static int i8k_set_fan(int fan, int speed)
261 {
262         struct smm_regs regs = { .eax = I8K_SMM_SET_FAN, };
263
264         speed = (speed < 0) ? 0 : ((speed > I8K_FAN_MAX) ? I8K_FAN_MAX : speed);
265         regs.ebx = (fan & 0xff) | (speed << 8);
266
267         return i8k_smm(&regs) ? : i8k_get_fan_status(fan);
268 }
269
270 /*
271  * Read the cpu temperature.
272  */
273 static int i8k_get_temp(int sensor)
274 {
275         struct smm_regs regs = { .eax = I8K_SMM_GET_TEMP, };
276         int rc;
277         int temp;
278
279 #ifdef I8K_TEMPERATURE_BUG
280         static int prev;
281 #endif
282         regs.ebx = sensor & 0xff;
283         if ((rc = i8k_smm(&regs)) < 0)
284                 return rc;
285
286         temp = regs.eax & 0xff;
287
288 #ifdef I8K_TEMPERATURE_BUG
289         /*
290          * Sometimes the temperature sensor returns 0x99, which is out of range.
291          * In this case we return (once) the previous cached value. For example:
292          # 1003655137 00000058 00005a4b
293          # 1003655138 00000099 00003a80 <--- 0x99 = 153 degrees
294          # 1003655139 00000054 00005c52
295          */
296         if (temp > I8K_MAX_TEMP) {
297                 temp = prev;
298                 prev = I8K_MAX_TEMP;
299         } else {
300                 prev = temp;
301         }
302 #endif
303
304         return temp;
305 }
306
307 static int i8k_get_dell_signature(int req_fn)
308 {
309         struct smm_regs regs = { .eax = req_fn, };
310         int rc;
311
312         if ((rc = i8k_smm(&regs)) < 0)
313                 return rc;
314
315         return regs.eax == 1145651527 && regs.edx == 1145392204 ? 0 : -1;
316 }
317
318 static int
319 i8k_ioctl_unlocked(struct file *fp, unsigned int cmd, unsigned long arg)
320 {
321         int val = 0;
322         int speed;
323         unsigned char buff[16];
324         int __user *argp = (int __user *)arg;
325
326         if (!argp)
327                 return -EINVAL;
328
329         switch (cmd) {
330         case I8K_BIOS_VERSION:
331                 val = i8k_get_bios_version();
332                 break;
333
334         case I8K_MACHINE_ID:
335                 memset(buff, 0, 16);
336                 strlcpy(buff, i8k_get_dmi_data(DMI_PRODUCT_SERIAL), sizeof(buff));
337                 break;
338
339         case I8K_FN_STATUS:
340                 val = i8k_get_fn_status();
341                 break;
342
343         case I8K_POWER_STATUS:
344                 val = i8k_get_power_status();
345                 break;
346
347         case I8K_GET_TEMP:
348                 val = i8k_get_temp(0);
349                 break;
350
351         case I8K_GET_SPEED:
352                 if (copy_from_user(&val, argp, sizeof(int)))
353                         return -EFAULT;
354
355                 val = i8k_get_fan_speed(val);
356                 break;
357
358         case I8K_GET_FAN:
359                 if (copy_from_user(&val, argp, sizeof(int)))
360                         return -EFAULT;
361
362                 val = i8k_get_fan_status(val);
363                 break;
364
365         case I8K_SET_FAN:
366                 if (restricted && !capable(CAP_SYS_ADMIN))
367                         return -EPERM;
368
369                 if (copy_from_user(&val, argp, sizeof(int)))
370                         return -EFAULT;
371
372                 if (copy_from_user(&speed, argp + 1, sizeof(int)))
373                         return -EFAULT;
374
375                 val = i8k_set_fan(val, speed);
376                 break;
377
378         default:
379                 return -EINVAL;
380         }
381
382         if (val < 0)
383                 return val;
384
385         switch (cmd) {
386         case I8K_BIOS_VERSION:
387                 if (copy_to_user(argp, &val, 4))
388                         return -EFAULT;
389
390                 break;
391         case I8K_MACHINE_ID:
392                 if (copy_to_user(argp, buff, 16))
393                         return -EFAULT;
394
395                 break;
396         default:
397                 if (copy_to_user(argp, &val, sizeof(int)))
398                         return -EFAULT;
399
400                 break;
401         }
402
403         return 0;
404 }
405
406 static long i8k_ioctl(struct file *fp, unsigned int cmd, unsigned long arg)
407 {
408         long ret;
409
410         mutex_lock(&i8k_mutex);
411         ret = i8k_ioctl_unlocked(fp, cmd, arg);
412         mutex_unlock(&i8k_mutex);
413
414         return ret;
415 }
416
417 /*
418  * Print the information for /proc/i8k.
419  */
420 static int i8k_proc_show(struct seq_file *seq, void *offset)
421 {
422         int fn_key, cpu_temp, ac_power;
423         int left_fan, right_fan, left_speed, right_speed;
424
425         cpu_temp        = i8k_get_temp(0);                      /* 11100 µs */
426         left_fan        = i8k_get_fan_status(I8K_FAN_LEFT);     /*   580 µs */
427         right_fan       = i8k_get_fan_status(I8K_FAN_RIGHT);    /*   580 µs */
428         left_speed      = i8k_get_fan_speed(I8K_FAN_LEFT);      /*   580 µs */
429         right_speed     = i8k_get_fan_speed(I8K_FAN_RIGHT);     /*   580 µs */
430         fn_key          = i8k_get_fn_status();                  /*   750 µs */
431         if (power_status)
432                 ac_power = i8k_get_power_status();              /* 14700 µs */
433         else
434                 ac_power = -1;
435
436         /*
437          * Info:
438          *
439          * 1)  Format version (this will change if format changes)
440          * 2)  BIOS version
441          * 3)  BIOS machine ID
442          * 4)  Cpu temperature
443          * 5)  Left fan status
444          * 6)  Right fan status
445          * 7)  Left fan speed
446          * 8)  Right fan speed
447          * 9)  AC power
448          * 10) Fn Key status
449          */
450         return seq_printf(seq, "%s %s %s %d %d %d %d %d %d %d\n",
451                           I8K_PROC_FMT,
452                           bios_version,
453                           i8k_get_dmi_data(DMI_PRODUCT_SERIAL),
454                           cpu_temp,
455                           left_fan, right_fan, left_speed, right_speed,
456                           ac_power, fn_key);
457 }
458
459 static int i8k_open_fs(struct inode *inode, struct file *file)
460 {
461         return single_open(file, i8k_proc_show, NULL);
462 }
463
464
465 /*
466  * Hwmon interface
467  */
468
469 static ssize_t i8k_hwmon_show_temp(struct device *dev,
470                                    struct device_attribute *devattr,
471                                    char *buf)
472 {
473         int cpu_temp;
474
475         cpu_temp = i8k_get_temp(0);
476         if (cpu_temp < 0)
477                 return cpu_temp;
478         return sprintf(buf, "%d\n", cpu_temp * 1000);
479 }
480
481 static ssize_t i8k_hwmon_show_fan(struct device *dev,
482                                   struct device_attribute *devattr,
483                                   char *buf)
484 {
485         int index = to_sensor_dev_attr(devattr)->index;
486         int fan_speed;
487
488         fan_speed = i8k_get_fan_speed(index);
489         if (fan_speed < 0)
490                 return fan_speed;
491         return sprintf(buf, "%d\n", fan_speed);
492 }
493
494 static ssize_t i8k_hwmon_show_label(struct device *dev,
495                                     struct device_attribute *devattr,
496                                     char *buf)
497 {
498         static const char *labels[4] = {
499                 "i8k",
500                 "CPU",
501                 "Left Fan",
502                 "Right Fan",
503         };
504         int index = to_sensor_dev_attr(devattr)->index;
505
506         return sprintf(buf, "%s\n", labels[index]);
507 }
508
509 static DEVICE_ATTR(temp1_input, S_IRUGO, i8k_hwmon_show_temp, NULL);
510 static SENSOR_DEVICE_ATTR(fan1_input, S_IRUGO, i8k_hwmon_show_fan, NULL,
511                           I8K_FAN_LEFT);
512 static SENSOR_DEVICE_ATTR(fan2_input, S_IRUGO, i8k_hwmon_show_fan, NULL,
513                           I8K_FAN_RIGHT);
514 static SENSOR_DEVICE_ATTR(name, S_IRUGO, i8k_hwmon_show_label, NULL, 0);
515 static SENSOR_DEVICE_ATTR(temp1_label, S_IRUGO, i8k_hwmon_show_label, NULL, 1);
516 static SENSOR_DEVICE_ATTR(fan1_label, S_IRUGO, i8k_hwmon_show_label, NULL, 2);
517 static SENSOR_DEVICE_ATTR(fan2_label, S_IRUGO, i8k_hwmon_show_label, NULL, 3);
518
519 static void i8k_hwmon_remove_files(struct device *dev)
520 {
521         device_remove_file(dev, &dev_attr_temp1_input);
522         device_remove_file(dev, &sensor_dev_attr_fan1_input.dev_attr);
523         device_remove_file(dev, &sensor_dev_attr_fan2_input.dev_attr);
524         device_remove_file(dev, &sensor_dev_attr_temp1_label.dev_attr);
525         device_remove_file(dev, &sensor_dev_attr_fan1_label.dev_attr);
526         device_remove_file(dev, &sensor_dev_attr_fan2_label.dev_attr);
527         device_remove_file(dev, &sensor_dev_attr_name.dev_attr);
528 }
529
530 static int __init i8k_init_hwmon(void)
531 {
532         int err;
533
534         i8k_hwmon_dev = hwmon_device_register(NULL);
535         if (IS_ERR(i8k_hwmon_dev)) {
536                 err = PTR_ERR(i8k_hwmon_dev);
537                 i8k_hwmon_dev = NULL;
538                 printk(KERN_ERR "i8k: hwmon registration failed (%d)\n", err);
539                 return err;
540         }
541
542         /* Required name attribute */
543         err = device_create_file(i8k_hwmon_dev,
544                                  &sensor_dev_attr_name.dev_attr);
545         if (err)
546                 goto exit_unregister;
547
548         /* CPU temperature attributes, if temperature reading is OK */
549         err = i8k_get_temp(0);
550         if (err < 0) {
551                 dev_dbg(i8k_hwmon_dev,
552                         "Not creating temperature attributes (%d)\n", err);
553         } else {
554                 err = device_create_file(i8k_hwmon_dev, &dev_attr_temp1_input);
555                 if (err)
556                         goto exit_remove_files;
557                 err = device_create_file(i8k_hwmon_dev,
558                                          &sensor_dev_attr_temp1_label.dev_attr);
559                 if (err)
560                         goto exit_remove_files;
561         }
562
563         /* Left fan attributes, if left fan is present */
564         err = i8k_get_fan_status(I8K_FAN_LEFT);
565         if (err < 0) {
566                 dev_dbg(i8k_hwmon_dev,
567                         "Not creating %s fan attributes (%d)\n", "left", err);
568         } else {
569                 err = device_create_file(i8k_hwmon_dev,
570                                          &sensor_dev_attr_fan1_input.dev_attr);
571                 if (err)
572                         goto exit_remove_files;
573                 err = device_create_file(i8k_hwmon_dev,
574                                          &sensor_dev_attr_fan1_label.dev_attr);
575                 if (err)
576                         goto exit_remove_files;
577         }
578
579         /* Right fan attributes, if right fan is present */
580         err = i8k_get_fan_status(I8K_FAN_RIGHT);
581         if (err < 0) {
582                 dev_dbg(i8k_hwmon_dev,
583                         "Not creating %s fan attributes (%d)\n", "right", err);
584         } else {
585                 err = device_create_file(i8k_hwmon_dev,
586                                          &sensor_dev_attr_fan2_input.dev_attr);
587                 if (err)
588                         goto exit_remove_files;
589                 err = device_create_file(i8k_hwmon_dev,
590                                          &sensor_dev_attr_fan2_label.dev_attr);
591                 if (err)
592                         goto exit_remove_files;
593         }
594
595         return 0;
596
597  exit_remove_files:
598         i8k_hwmon_remove_files(i8k_hwmon_dev);
599  exit_unregister:
600         hwmon_device_unregister(i8k_hwmon_dev);
601         return err;
602 }
603
604 static void __exit i8k_exit_hwmon(void)
605 {
606         i8k_hwmon_remove_files(i8k_hwmon_dev);
607         hwmon_device_unregister(i8k_hwmon_dev);
608 }
609
610 static struct dmi_system_id __initdata i8k_dmi_table[] = {
611         {
612                 .ident = "Dell Inspiron",
613                 .matches = {
614                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer"),
615                         DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron"),
616                 },
617         },
618         {
619                 .ident = "Dell Latitude",
620                 .matches = {
621                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer"),
622                         DMI_MATCH(DMI_PRODUCT_NAME, "Latitude"),
623                 },
624         },
625         {
626                 .ident = "Dell Inspiron 2",
627                 .matches = {
628                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
629                         DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron"),
630                 },
631         },
632         {
633                 .ident = "Dell Latitude 2",
634                 .matches = {
635                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
636                         DMI_MATCH(DMI_PRODUCT_NAME, "Latitude"),
637                 },
638         },
639         {       /* UK Inspiron 6400  */
640                 .ident = "Dell Inspiron 3",
641                 .matches = {
642                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
643                         DMI_MATCH(DMI_PRODUCT_NAME, "MM061"),
644                 },
645         },
646         {
647                 .ident = "Dell Inspiron 3",
648                 .matches = {
649                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
650                         DMI_MATCH(DMI_PRODUCT_NAME, "MP061"),
651                 },
652         },
653         {
654                 .ident = "Dell Precision",
655                 .matches = {
656                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
657                         DMI_MATCH(DMI_PRODUCT_NAME, "Precision"),
658                 },
659         },
660         {
661                 .ident = "Dell Vostro",
662                 .matches = {
663                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
664                         DMI_MATCH(DMI_PRODUCT_NAME, "Vostro"),
665                 },
666         },
667         { }
668 };
669
670 /*
671  * Probe for the presence of a supported laptop.
672  */
673 static int __init i8k_probe(void)
674 {
675         char buff[4];
676         int version;
677
678         /*
679          * Get DMI information
680          */
681         if (!dmi_check_system(i8k_dmi_table)) {
682                 if (!ignore_dmi && !force)
683                         return -ENODEV;
684
685                 printk(KERN_INFO "i8k: not running on a supported Dell system.\n");
686                 printk(KERN_INFO "i8k: vendor=%s, model=%s, version=%s\n",
687                         i8k_get_dmi_data(DMI_SYS_VENDOR),
688                         i8k_get_dmi_data(DMI_PRODUCT_NAME),
689                         i8k_get_dmi_data(DMI_BIOS_VERSION));
690         }
691
692         strlcpy(bios_version, i8k_get_dmi_data(DMI_BIOS_VERSION), sizeof(bios_version));
693
694         /*
695          * Get SMM Dell signature
696          */
697         if (i8k_get_dell_signature(I8K_SMM_GET_DELL_SIG1) &&
698             i8k_get_dell_signature(I8K_SMM_GET_DELL_SIG2)) {
699                 printk(KERN_ERR "i8k: unable to get SMM Dell signature\n");
700                 if (!force)
701                         return -ENODEV;
702         }
703
704         /*
705          * Get SMM BIOS version.
706          */
707         version = i8k_get_bios_version();
708         if (version <= 0) {
709                 printk(KERN_WARNING "i8k: unable to get SMM BIOS version\n");
710         } else {
711                 buff[0] = (version >> 16) & 0xff;
712                 buff[1] = (version >> 8) & 0xff;
713                 buff[2] = (version) & 0xff;
714                 buff[3] = '\0';
715                 /*
716                  * If DMI BIOS version is unknown use SMM BIOS version.
717                  */
718                 if (!dmi_get_system_info(DMI_BIOS_VERSION))
719                         strlcpy(bios_version, buff, sizeof(bios_version));
720
721                 /*
722                  * Check if the two versions match.
723                  */
724                 if (strncmp(buff, bios_version, sizeof(bios_version)) != 0)
725                         printk(KERN_WARNING "i8k: BIOS version mismatch: %s != %s\n",
726                                 buff, bios_version);
727         }
728
729         return 0;
730 }
731
732 static int __init i8k_init(void)
733 {
734         struct proc_dir_entry *proc_i8k;
735         int err;
736
737         /* Are we running on an supported laptop? */
738         if (i8k_probe())
739                 return -ENODEV;
740
741         /* Register the proc entry */
742         proc_i8k = proc_create("i8k", 0, NULL, &i8k_fops);
743         if (!proc_i8k)
744                 return -ENOENT;
745
746         err = i8k_init_hwmon();
747         if (err)
748                 goto exit_remove_proc;
749
750         printk(KERN_INFO
751                "Dell laptop SMM driver v%s Massimo Dal Zotto (dz@debian.org)\n",
752                I8K_VERSION);
753
754         return 0;
755
756  exit_remove_proc:
757         remove_proc_entry("i8k", NULL);
758         return err;
759 }
760
761 static void __exit i8k_exit(void)
762 {
763         i8k_exit_hwmon();
764         remove_proc_entry("i8k", NULL);
765 }
766
767 module_init(i8k_init);
768 module_exit(i8k_exit);