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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  23
  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
  37 #include <linux/i8k.h>
  38
  39 #define I8K_VERSION             "1.14 21/02/2005"
  40
  41 #define I8K_SMM_FN_STATUS       0x0025
  42 #define I8K_SMM_POWER_STATUS    0x0069
  43 #define I8K_SMM_SET_FAN         0x01a3
  44 #define I8K_SMM_GET_FAN         0x00a3
  45 #define I8K_SMM_GET_SPEED       0x02a3
  46 #define I8K_SMM_GET_TEMP        0x10a3
  47 #define I8K_SMM_GET_DELL_SIG1   0xfea3
  48 #define I8K_SMM_GET_DELL_SIG2   0xffa3
  49 #define I8K_SMM_BIOS_VERSION    0x00a6
  50
  51 #define I8K_FAN_MULT            30
  52 #define I8K_MAX_TEMP            127
  53
  54 #define I8K_FN_NONE             0x00
  55 #define I8K_FN_UP               0x01
  56 #define I8K_FN_DOWN             0x02
  57 #define I8K_FN_MUTE             0x04
  58 #define I8K_FN_MASK             0x07
  59 #define I8K_FN_SHIFT            8
  60
  61 #define I8K_POWER_AC            0x05
  62 #define I8K_POWER_BATTERY       0x01
  63
  64 #define I8K_TEMPERATURE_BUG     1
  65
  66 static DEFINE_MUTEX(i8k_mutex);
  67 static char bios_version[4];
  68 static struct device *i8k_hwmon_dev;
  69
  70 MODULE_AUTHOR("Massimo Dal Zotto (dz@debian.org)");
  71 MODULE_DESCRIPTION("Driver for accessing SMM BIOS on Dell laptops");
  72 MODULE_LICENSE("GPL");
  73
  74 static bool force;
  75 module_param(force, bool, 0);
  76 MODULE_PARM_DESC(force, "Force loading without checking for supported models");
  77
  78 static bool ignore_dmi;
  79 module_param(ignore_dmi, bool, 0);
  80 MODULE_PARM_DESC(ignore_dmi, "Continue probing hardware even if DMI data does not match");
  81
  82 static bool restricted;
  83 module_param(restricted, bool, 0);
  84 MODULE_PARM_DESC(restricted, "Allow fan control if SYS_ADMIN capability set");
  85
  86 static bool power_status;
  87 module_param(power_status, bool, 0600);
  88 MODULE_PARM_DESC(power_status, "Report power status in /proc/i8k");
  89
  90 static int fan_mult = I8K_FAN_MULT;
  91 module_param(fan_mult, int, 0);
  92 MODULE_PARM_DESC(fan_mult, "Factor to multiply fan speed with");
  93
  94 static int i8k_open_fs(struct inode *inode, struct file *file);
  95 static long i8k_ioctl(struct file *, unsigned int, unsigned long);
  96
  97 static const struct file_operations i8k_fops = {
  98         .owner          = THIS_MODULE,
  99         .open           = i8k_open_fs,
 100         .read           = seq_read,
 101         .llseek         = seq_lseek,
 102         .release        = single_release,
 103         .unlocked_ioctl = i8k_ioctl,
 104 };
 105
 106 struct smm_regs {
 107         unsigned int eax;
 108         unsigned int ebx __packed;
 109         unsigned int ecx __packed;
 110         unsigned int edx __packed;
 111         unsigned int esi __packed;
 112         unsigned int edi __packed;
 113 };
 114
 115 static inline const char *i8k_get_dmi_data(int field)
 116 {
 117         const char *dmi_data = dmi_get_system_info(field);
 118
 119         return dmi_data && *dmi_data ? dmi_data : "?";
 120 }
 121
 122 /*
 123  * Call the System Management Mode BIOS. Code provided by Jonathan Buzzard.
 124  */
 125 static int i8k_smm(struct smm_regs *regs)
 126 {
 127         int rc;
 128         int eax = regs->eax;
 129
 130 #if defined(CONFIG_X86_64)
 131         asm volatile("pushq %%rax\n\t"
 132                 "movl 0(%%rax),%%edx\n\t"
 133                 "pushq %%rdx\n\t"
 134                 "movl 4(%%rax),%%ebx\n\t"
 135                 "movl 8(%%rax),%%ecx\n\t"
 136                 "movl 12(%%rax),%%edx\n\t"
 137                 "movl 16(%%rax),%%esi\n\t"
 138                 "movl 20(%%rax),%%edi\n\t"
 139                 "popq %%rax\n\t"
 140                 "out %%al,$0xb2\n\t"
 141                 "out %%al,$0x84\n\t"
 142                 "xchgq %%rax,(%%rsp)\n\t"
 143                 "movl %%ebx,4(%%rax)\n\t"
 144                 "movl %%ecx,8(%%rax)\n\t"
 145                 "movl %%edx,12(%%rax)\n\t"
 146                 "movl %%esi,16(%%rax)\n\t"
 147                 "movl %%edi,20(%%rax)\n\t"
 148                 "popq %%rdx\n\t"
 149                 "movl %%edx,0(%%rax)\n\t"
 150                 "pushfq\n\t"
 151                 "popq %%rax\n\t"
 152                 "andl $1,%%eax\n"
 153                 : "=a"(rc)
 154                 :    "a"(regs)
 155                 :    "%ebx", "%ecx", "%edx", "%esi", "%edi", "memory");
 156 #else
 157         asm volatile("pushl %%eax\n\t"
 158             "movl 0(%%eax),%%edx\n\t"
 159             "push %%edx\n\t"
 160             "movl 4(%%eax),%%ebx\n\t"
 161             "movl 8(%%eax),%%ecx\n\t"
 162             "movl 12(%%eax),%%edx\n\t"
 163             "movl 16(%%eax),%%esi\n\t"
 164             "movl 20(%%eax),%%edi\n\t"
 165             "popl %%eax\n\t"
 166             "out %%al,$0xb2\n\t"
 167             "out %%al,$0x84\n\t"
 168             "xchgl %%eax,(%%esp)\n\t"
 169             "movl %%ebx,4(%%eax)\n\t"
 170             "movl %%ecx,8(%%eax)\n\t"
 171             "movl %%edx,12(%%eax)\n\t"
 172             "movl %%esi,16(%%eax)\n\t"
 173             "movl %%edi,20(%%eax)\n\t"
 174             "popl %%edx\n\t"
 175             "movl %%edx,0(%%eax)\n\t"
 176             "lahf\n\t"
 177             "shrl $8,%%eax\n\t"
 178             "andl $1,%%eax\n"
 179             : "=a"(rc)
 180             :    "a"(regs)
 181             :    "%ebx", "%ecx", "%edx", "%esi", "%edi", "memory");
 182 #endif
 183         if (rc != 0 || (regs->eax & 0xffff) == 0xffff || regs->eax == eax)
 184                 return -EINVAL;
 185
 186         return 0;
 187 }
 188
 189 /*
 190  * Read the bios version. Return the version as an integer corresponding
 191  * to the ascii value, for example "A17" is returned as 0x00413137.
 192  */
 193 static int i8k_get_bios_version(void)
 194 {
 195         struct smm_regs regs = { .eax = I8K_SMM_BIOS_VERSION, };
 196
 197         return i8k_smm(&regs) ? : regs.eax;
 198 }
 199
 200 /*
 201  * Read the Fn key status.
 202  */
 203 static int i8k_get_fn_status(void)
 204 {
 205         struct smm_regs regs = { .eax = I8K_SMM_FN_STATUS, };
 206         int rc;
 207
 208         rc = i8k_smm(&regs);
 209         if (rc < 0)
 210                 return rc;
 211
 212         switch ((regs.eax >> I8K_FN_SHIFT) & I8K_FN_MASK) {
 213         case I8K_FN_UP:
 214                 return I8K_VOL_UP;
 215         case I8K_FN_DOWN:
 216                 return I8K_VOL_DOWN;
 217         case I8K_FN_MUTE:
 218                 return I8K_VOL_MUTE;
 219         default:
 220                 return 0;
 221         }
 222 }
 223
 224 /*
 225  * Read the power status.
 226  */
 227 static int i8k_get_power_status(void)
 228 {
 229         struct smm_regs regs = { .eax = I8K_SMM_POWER_STATUS, };
 230         int rc;
 231
 232         rc = i8k_smm(&regs);
 233         if (rc < 0)
 234                 return rc;
 235
 236         return (regs.eax & 0xff) == I8K_POWER_AC ? I8K_AC : I8K_BATTERY;
 237 }
 238
 239 /*
 240  * Read the fan status.
 241  */
 242 static int i8k_get_fan_status(int fan)
 243 {
 244         struct smm_regs regs = { .eax = I8K_SMM_GET_FAN, };
 245
 246         regs.ebx = fan & 0xff;
 247         return i8k_smm(&regs) ? : regs.eax & 0xff;
 248 }
 249
 250 /*
 251  * Read the fan speed in RPM.
 252  */
 253 static int i8k_get_fan_speed(int fan)
 254 {
 255         struct smm_regs regs = { .eax = I8K_SMM_GET_SPEED, };
 256
 257         regs.ebx = fan & 0xff;
 258         return i8k_smm(&regs) ? : (regs.eax & 0xffff) * fan_mult;
 259 }
 260
 261 /*
 262  * Set the fan speed (off, low, high). Returns the new fan status.
 263  */
 264 static int i8k_set_fan(int fan, int speed)
 265 {
 266         struct smm_regs regs = { .eax = I8K_SMM_SET_FAN, };
 267
 268         speed = (speed < 0) ? 0 : ((speed > I8K_FAN_MAX) ? I8K_FAN_MAX : speed);
 269         regs.ebx = (fan & 0xff) | (speed << 8);
 270
 271         return i8k_smm(&regs) ? : i8k_get_fan_status(fan);
 272 }
 273
 274 /*
 275  * Read the cpu temperature.
 276  */
 277 static int i8k_get_temp(int sensor)
 278 {
 279         struct smm_regs regs = { .eax = I8K_SMM_GET_TEMP, };
 280         int rc;
 281         int temp;
 282
 283 #ifdef I8K_TEMPERATURE_BUG
 284         static int prev;
 285 #endif
 286         regs.ebx = sensor & 0xff;
 287         rc = i8k_smm(&regs);
 288         if (rc < 0)
 289                 return rc;
 290
 291         temp = regs.eax & 0xff;
 292
 293 #ifdef I8K_TEMPERATURE_BUG
 294         /*
 295          * Sometimes the temperature sensor returns 0x99, which is out of range.
 296          * In this case we return (once) the previous cached value. For example:
 297          # 1003655137 00000058 00005a4b
 298          # 1003655138 00000099 00003a80 <--- 0x99 = 153 degrees
 299          # 1003655139 00000054 00005c52
 300          */
 301         if (temp > I8K_MAX_TEMP) {
 302                 temp = prev;
 303                 prev = I8K_MAX_TEMP;
 304         } else {
 305                 prev = temp;
 306         }
 307 #endif
 308
 309         return temp;
 310 }
 311
 312 static int i8k_get_dell_signature(int req_fn)
 313 {
 314         struct smm_regs regs = { .eax = req_fn, };
 315         int rc;
 316
 317         rc = i8k_smm(&regs);
 318         if (rc < 0)
 319                 return rc;
 320
 321         return regs.eax == 1145651527 && regs.edx == 1145392204 ? 0 : -1;
 322 }
 323
 324 static int
 325 i8k_ioctl_unlocked(struct file *fp, unsigned int cmd, unsigned long arg)
 326 {
 327         int val = 0;
 328         int speed;
 329         unsigned char buff[16];
 330         int __user *argp = (int __user *)arg;
 331
 332         if (!argp)
 333                 return -EINVAL;
 334
 335         switch (cmd) {
 336         case I8K_BIOS_VERSION:
 337                 val = i8k_get_bios_version();
 338                 break;
 339
 340         case I8K_MACHINE_ID:
 341                 memset(buff, 0, 16);
 342                 strlcpy(buff, i8k_get_dmi_data(DMI_PRODUCT_SERIAL),
 343                         sizeof(buff));
 344                 break;
 345
 346         case I8K_FN_STATUS:
 347                 val = i8k_get_fn_status();
 348                 break;
 349
 350         case I8K_POWER_STATUS:
 351                 val = i8k_get_power_status();
 352                 break;
 353
 354         case I8K_GET_TEMP:
 355                 val = i8k_get_temp(0);
 356                 break;
 357
 358         case I8K_GET_SPEED:
 359                 if (copy_from_user(&val, argp, sizeof(int)))
 360                         return -EFAULT;
 361
 362                 val = i8k_get_fan_speed(val);
 363                 break;
 364
 365         case I8K_GET_FAN:
 366                 if (copy_from_user(&val, argp, sizeof(int)))
 367                         return -EFAULT;
 368
 369                 val = i8k_get_fan_status(val);
 370                 break;
 371
 372         case I8K_SET_FAN:
 373                 if (restricted && !capable(CAP_SYS_ADMIN))
 374                         return -EPERM;
 375
 376                 if (copy_from_user(&val, argp, sizeof(int)))
 377                         return -EFAULT;
 378
 379                 if (copy_from_user(&speed, argp + 1, sizeof(int)))
 380                         return -EFAULT;
 381
 382                 val = i8k_set_fan(val, speed);
 383                 break;
 384
 385         default:
 386                 return -EINVAL;
 387         }
 388
 389         if (val < 0)
 390                 return val;
 391
 392         switch (cmd) {
 393         case I8K_BIOS_VERSION:
 394                 if (copy_to_user(argp, &val, 4))
 395                         return -EFAULT;
 396
 397                 break;
 398         case I8K_MACHINE_ID:
 399                 if (copy_to_user(argp, buff, 16))
 400                         return -EFAULT;
 401
 402                 break;
 403         default:
 404                 if (copy_to_user(argp, &val, sizeof(int)))
 405                         return -EFAULT;
 406
 407                 break;
 408         }
 409
 410         return 0;
 411 }
 412
 413 static long i8k_ioctl(struct file *fp, unsigned int cmd, unsigned long arg)
 414 {
 415         long ret;
 416
 417         mutex_lock(&i8k_mutex);
 418         ret = i8k_ioctl_unlocked(fp, cmd, arg);
 419         mutex_unlock(&i8k_mutex);
 420
 421         return ret;
 422 }
 423
 424 /*
 425  * Print the information for /proc/i8k.
 426  */
 427 static int i8k_proc_show(struct seq_file *seq, void *offset)
 428 {
 429         int fn_key, cpu_temp, ac_power;
 430         int left_fan, right_fan, left_speed, right_speed;
 431
 432         cpu_temp        = i8k_get_temp(0);                      /* 11100 µs */
 433         left_fan        = i8k_get_fan_status(I8K_FAN_LEFT);     /*   580 µs */
 434         right_fan       = i8k_get_fan_status(I8K_FAN_RIGHT);    /*   580 µs */
 435         left_speed      = i8k_get_fan_speed(I8K_FAN_LEFT);      /*   580 µs */
 436         right_speed     = i8k_get_fan_speed(I8K_FAN_RIGHT);     /*   580 µs */
 437         fn_key          = i8k_get_fn_status();                  /*   750 µs */
 438         if (power_status)
 439                 ac_power = i8k_get_power_status();              /* 14700 µs */
 440         else
 441                 ac_power = -1;
 442
 443         /*
 444          * Info:
 445          *
 446          * 1)  Format version (this will change if format changes)
 447          * 2)  BIOS version
 448          * 3)  BIOS machine ID
 449          * 4)  Cpu temperature
 450          * 5)  Left fan status
 451          * 6)  Right fan status
 452          * 7)  Left fan speed
 453          * 8)  Right fan speed
 454          * 9)  AC power
 455          * 10) Fn Key status
 456          */
 457         return seq_printf(seq, "%s %s %s %d %d %d %d %d %d %d\n",
 458                           I8K_PROC_FMT,
 459                           bios_version,
 460                           i8k_get_dmi_data(DMI_PRODUCT_SERIAL),
 461                           cpu_temp,
 462                           left_fan, right_fan, left_speed, right_speed,
 463                           ac_power, fn_key);
 464 }
 465
 466 static int i8k_open_fs(struct inode *inode, struct file *file)
 467 {
 468         return single_open(file, i8k_proc_show, NULL);
 469 }
 470
 471
 472 /*
 473  * Hwmon interface
 474  */
 475
 476 static ssize_t i8k_hwmon_show_temp(struct device *dev,
 477                                    struct device_attribute *devattr,
 478                                    char *buf)
 479 {
 480         int cpu_temp;
 481
 482         cpu_temp = i8k_get_temp(0);
 483         if (cpu_temp < 0)
 484                 return cpu_temp;
 485         return sprintf(buf, "%d\n", cpu_temp * 1000);
 486 }
 487
 488 static ssize_t i8k_hwmon_show_fan(struct device *dev,
 489                                   struct device_attribute *devattr,
 490                                   char *buf)
 491 {
 492         int index = to_sensor_dev_attr(devattr)->index;
 493         int fan_speed;
 494
 495         fan_speed = i8k_get_fan_speed(index);
 496         if (fan_speed < 0)
 497                 return fan_speed;
 498         return sprintf(buf, "%d\n", fan_speed);
 499 }
 500
 501 static ssize_t i8k_hwmon_show_label(struct device *dev,
 502                                     struct device_attribute *devattr,
 503                                     char *buf)
 504 {
 505         static const char *labels[4] = {
 506                 "i8k",
 507                 "CPU",
 508                 "Left Fan",
 509                 "Right Fan",
 510         };
 511         int index = to_sensor_dev_attr(devattr)->index;
 512
 513         return sprintf(buf, "%s\n", labels[index]);
 514 }
 515
 516 static DEVICE_ATTR(temp1_input, S_IRUGO, i8k_hwmon_show_temp, NULL);
 517 static SENSOR_DEVICE_ATTR(fan1_input, S_IRUGO, i8k_hwmon_show_fan, NULL,
 518                           I8K_FAN_LEFT);
 519 static SENSOR_DEVICE_ATTR(fan2_input, S_IRUGO, i8k_hwmon_show_fan, NULL,
 520                           I8K_FAN_RIGHT);
 521 static SENSOR_DEVICE_ATTR(name, S_IRUGO, i8k_hwmon_show_label, NULL, 0);
 522 static SENSOR_DEVICE_ATTR(temp1_label, S_IRUGO, i8k_hwmon_show_label, NULL, 1);
 523 static SENSOR_DEVICE_ATTR(fan1_label, S_IRUGO, i8k_hwmon_show_label, NULL, 2);
 524 static SENSOR_DEVICE_ATTR(fan2_label, S_IRUGO, i8k_hwmon_show_label, NULL, 3);
 525
 526 static void i8k_hwmon_remove_files(struct device *dev)
 527 {
 528         device_remove_file(dev, &dev_attr_temp1_input);
 529         device_remove_file(dev, &sensor_dev_attr_fan1_input.dev_attr);
 530         device_remove_file(dev, &sensor_dev_attr_fan2_input.dev_attr);
 531         device_remove_file(dev, &sensor_dev_attr_temp1_label.dev_attr);
 532         device_remove_file(dev, &sensor_dev_attr_fan1_label.dev_attr);
 533         device_remove_file(dev, &sensor_dev_attr_fan2_label.dev_attr);
 534         device_remove_file(dev, &sensor_dev_attr_name.dev_attr);
 535 }
 536
 537 static int __init i8k_init_hwmon(void)
 538 {
 539         int err;
 540
 541         i8k_hwmon_dev = hwmon_device_register(NULL);
 542         if (IS_ERR(i8k_hwmon_dev)) {
 543                 err = PTR_ERR(i8k_hwmon_dev);
 544                 i8k_hwmon_dev = NULL;
 545                 pr_err("hwmon registration failed (%d)\n", err);
 546                 return err;
 547         }
 548
 549         /* Required name attribute */
 550         err = device_create_file(i8k_hwmon_dev,
 551                                  &sensor_dev_attr_name.dev_attr);
 552         if (err)
 553                 goto exit_unregister;
 554
 555         /* CPU temperature attributes, if temperature reading is OK */
 556         err = i8k_get_temp(0);
 557         if (err < 0) {
 558                 dev_dbg(i8k_hwmon_dev,
 559                         "Not creating temperature attributes (%d)\n", err);
 560         } else {
 561                 err = device_create_file(i8k_hwmon_dev, &dev_attr_temp1_input);
 562                 if (err)
 563                         goto exit_remove_files;
 564                 err = device_create_file(i8k_hwmon_dev,
 565                                          &sensor_dev_attr_temp1_label.dev_attr);
 566                 if (err)
 567                         goto exit_remove_files;
 568         }
 569
 570         /* Left fan attributes, if left fan is present */
 571         err = i8k_get_fan_status(I8K_FAN_LEFT);
 572         if (err < 0) {
 573                 dev_dbg(i8k_hwmon_dev,
 574                         "Not creating %s fan attributes (%d)\n", "left", err);
 575         } else {
 576                 err = device_create_file(i8k_hwmon_dev,
 577                                          &sensor_dev_attr_fan1_input.dev_attr);
 578                 if (err)
 579                         goto exit_remove_files;
 580                 err = device_create_file(i8k_hwmon_dev,
 581                                          &sensor_dev_attr_fan1_label.dev_attr);
 582                 if (err)
 583                         goto exit_remove_files;
 584         }
 585
 586         /* Right fan attributes, if right fan is present */
 587         err = i8k_get_fan_status(I8K_FAN_RIGHT);
 588         if (err < 0) {
 589                 dev_dbg(i8k_hwmon_dev,
 590                         "Not creating %s fan attributes (%d)\n", "right", err);
 591         } else {
 592                 err = device_create_file(i8k_hwmon_dev,
 593                                          &sensor_dev_attr_fan2_input.dev_attr);
 594                 if (err)
 595                         goto exit_remove_files;
 596                 err = device_create_file(i8k_hwmon_dev,
 597                                          &sensor_dev_attr_fan2_label.dev_attr);
 598                 if (err)
 599                         goto exit_remove_files;
 600         }
 601
 602         return 0;
 603
 604  exit_remove_files:
 605         i8k_hwmon_remove_files(i8k_hwmon_dev);
 606  exit_unregister:
 607         hwmon_device_unregister(i8k_hwmon_dev);
 608         return err;
 609 }
 610
 611 static void __exit i8k_exit_hwmon(void)
 612 {
 613         i8k_hwmon_remove_files(i8k_hwmon_dev);
 614         hwmon_device_unregister(i8k_hwmon_dev);
 615 }
 616
 617 static struct dmi_system_id i8k_dmi_table[] __initdata = {
 618         {
 619                 .ident = "Dell Inspiron",
 620                 .matches = {
 621                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer"),
 622                         DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron"),
 623                 },
 624         },
 625         {
 626                 .ident = "Dell Latitude",
 627                 .matches = {
 628                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer"),
 629                         DMI_MATCH(DMI_PRODUCT_NAME, "Latitude"),
 630                 },
 631         },
 632         {
 633                 .ident = "Dell Inspiron 2",
 634                 .matches = {
 635                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 636                         DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron"),
 637                 },
 638         },
 639         {
 640                 .ident = "Dell Latitude 2",
 641                 .matches = {
 642                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 643                         DMI_MATCH(DMI_PRODUCT_NAME, "Latitude"),
 644                 },
 645         },
 646         {       /* UK Inspiron 6400  */
 647                 .ident = "Dell Inspiron 3",
 648                 .matches = {
 649                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 650                         DMI_MATCH(DMI_PRODUCT_NAME, "MM061"),
 651                 },
 652         },
 653         {
 654                 .ident = "Dell Inspiron 3",
 655                 .matches = {
 656                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 657                         DMI_MATCH(DMI_PRODUCT_NAME, "MP061"),
 658                 },
 659         },
 660         {
 661                 .ident = "Dell Precision",
 662                 .matches = {
 663                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 664                         DMI_MATCH(DMI_PRODUCT_NAME, "Precision"),
 665                 },
 666         },
 667         {
 668                 .ident = "Dell Vostro",
 669                 .matches = {
 670                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 671                         DMI_MATCH(DMI_PRODUCT_NAME, "Vostro"),
 672                 },
 673         },
 674         {
 675                 .ident = "Dell XPS421",
 676                 .matches = {
 677                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 678                         DMI_MATCH(DMI_PRODUCT_NAME, "XPS L421X"),
 679                 },
 680         },
 681         { }
 682 };
 683
 684 /*
 685  * Probe for the presence of a supported laptop.
 686  */
 687 static int __init i8k_probe(void)
 688 {
 689         char buff[4];
 690         int version;
 691
 692         /*
 693          * Get DMI information
 694          */
 695         if (!dmi_check_system(i8k_dmi_table)) {
 696                 if (!ignore_dmi && !force)
 697                         return -ENODEV;
 698
 699                 pr_info("not running on a supported Dell system.\n");
 700                 pr_info("vendor=%s, model=%s, version=%s\n",
 701                         i8k_get_dmi_data(DMI_SYS_VENDOR),
 702                         i8k_get_dmi_data(DMI_PRODUCT_NAME),
 703                         i8k_get_dmi_data(DMI_BIOS_VERSION));
 704         }
 705
 706         strlcpy(bios_version, i8k_get_dmi_data(DMI_BIOS_VERSION),
 707                 sizeof(bios_version));
 708
 709         /*
 710          * Get SMM Dell signature
 711          */
 712         if (i8k_get_dell_signature(I8K_SMM_GET_DELL_SIG1) &&
 713             i8k_get_dell_signature(I8K_SMM_GET_DELL_SIG2)) {
 714                 pr_err("unable to get SMM Dell signature\n");
 715                 if (!force)
 716                         return -ENODEV;
 717         }
 718
 719         /*
 720          * Get SMM BIOS version.
 721          */
 722         version = i8k_get_bios_version();
 723         if (version <= 0) {
 724                 pr_warn("unable to get SMM BIOS version\n");
 725         } else {
 726                 buff[0] = (version >> 16) & 0xff;
 727                 buff[1] = (version >> 8) & 0xff;
 728                 buff[2] = (version) & 0xff;
 729                 buff[3] = '\0';
 730                 /*
 731                  * If DMI BIOS version is unknown use SMM BIOS version.
 732                  */
 733                 if (!dmi_get_system_info(DMI_BIOS_VERSION))
 734                         strlcpy(bios_version, buff, sizeof(bios_version));
 735
 736                 /*
 737                  * Check if the two versions match.
 738                  */
 739                 if (strncmp(buff, bios_version, sizeof(bios_version)) != 0)
 740                         pr_warn("BIOS version mismatch: %s != %s\n",
 741                                 buff, bios_version);
 742         }
 743
 744         return 0;
 745 }
 746
 747 static int __init i8k_init(void)
 748 {
 749         struct proc_dir_entry *proc_i8k;
 750         int err;
 751
 752         /* Are we running on an supported laptop? */
 753         if (i8k_probe())
 754                 return -ENODEV;
 755
 756         /* Register the proc entry */
 757         proc_i8k = proc_create("i8k", 0, NULL, &i8k_fops);
 758         if (!proc_i8k)
 759                 return -ENOENT;
 760
 761         err = i8k_init_hwmon();
 762         if (err)
 763                 goto exit_remove_proc;
 764
 765         pr_info("Dell laptop SMM driver v%s Massimo Dal Zotto (dz@debian.org)\n",
 766                 I8K_VERSION);
 767
 768         return 0;
 769
 770  exit_remove_proc:
 771         remove_proc_entry("i8k", NULL);
 772         return err;
 773 }
 774
 775 static void __exit i8k_exit(void)
 776 {
 777         i8k_exit_hwmon();
 778         remove_proc_entry("i8k", NULL);
 779 }
 780
 781 module_init(i8k_init);
 782 module_exit(i8k_exit);