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  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_TEMP_TYPE   0x11a3
  46 #define I8K_SMM_GET_DELL_SIG1   0xfea3
  47 #define I8K_SMM_GET_DELL_SIG2   0xffa3
  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 static u32 i8k_hwmon_flags;
  68 static int i8k_fan_mult;
  69 static int i8k_pwm_mult;
  70 static int i8k_fan_max = I8K_FAN_HIGH;
  71
  72 #define I8K_HWMON_HAVE_TEMP1    (1 << 0)
  73 #define I8K_HWMON_HAVE_TEMP2    (1 << 1)
  74 #define I8K_HWMON_HAVE_TEMP3    (1 << 2)
  75 #define I8K_HWMON_HAVE_TEMP4    (1 << 3)
  76 #define I8K_HWMON_HAVE_FAN1     (1 << 4)
  77 #define I8K_HWMON_HAVE_FAN2     (1 << 5)
  78
  79 MODULE_AUTHOR("Massimo Dal Zotto (dz@debian.org)");
  80 MODULE_DESCRIPTION("Driver for accessing SMM BIOS on Dell laptops");
  81 MODULE_LICENSE("GPL");
  82
  83 static bool force;
  84 module_param(force, bool, 0);
  85 MODULE_PARM_DESC(force, "Force loading without checking for supported models");
  86
  87 static bool ignore_dmi;
  88 module_param(ignore_dmi, bool, 0);
  89 MODULE_PARM_DESC(ignore_dmi, "Continue probing hardware even if DMI data does not match");
  90
  91 static bool restricted;
  92 module_param(restricted, bool, 0);
  93 MODULE_PARM_DESC(restricted, "Allow fan control if SYS_ADMIN capability set");
  94
  95 static bool power_status;
  96 module_param(power_status, bool, 0600);
  97 MODULE_PARM_DESC(power_status, "Report power status in /proc/i8k");
  98
  99 static int fan_mult = I8K_FAN_MULT;
 100 module_param(fan_mult, int, 0);
 101 MODULE_PARM_DESC(fan_mult, "Factor to multiply fan speed with");
 102
 103 static int fan_max = I8K_FAN_HIGH;
 104 module_param(fan_max, int, 0);
 105 MODULE_PARM_DESC(fan_max, "Maximum configurable fan speed");
 106
 107 static int i8k_open_fs(struct inode *inode, struct file *file);
 108 static long i8k_ioctl(struct file *, unsigned int, unsigned long);
 109
 110 static const struct file_operations i8k_fops = {
 111         .owner          = THIS_MODULE,
 112         .open           = i8k_open_fs,
 113         .read           = seq_read,
 114         .llseek         = seq_lseek,
 115         .release        = single_release,
 116         .unlocked_ioctl = i8k_ioctl,
 117 };
 118
 119 struct smm_regs {
 120         unsigned int eax;
 121         unsigned int ebx __packed;
 122         unsigned int ecx __packed;
 123         unsigned int edx __packed;
 124         unsigned int esi __packed;
 125         unsigned int edi __packed;
 126 };
 127
 128 static inline const char *i8k_get_dmi_data(int field)
 129 {
 130         const char *dmi_data = dmi_get_system_info(field);
 131
 132         return dmi_data && *dmi_data ? dmi_data : "?";
 133 }
 134
 135 /*
 136  * Call the System Management Mode BIOS. Code provided by Jonathan Buzzard.
 137  */
 138 static int i8k_smm(struct smm_regs *regs)
 139 {
 140         int rc;
 141         int eax = regs->eax;
 142         cpumask_var_t old_mask;
 143
 144         /* SMM requires CPU 0 */
 145         if (!alloc_cpumask_var(&old_mask, GFP_KERNEL))
 146                 return -ENOMEM;
 147         cpumask_copy(old_mask, &current->cpus_allowed);
 148         rc = set_cpus_allowed_ptr(current, cpumask_of(0));
 149         if (rc)
 150                 goto out;
 151         if (smp_processor_id() != 0) {
 152                 rc = -EBUSY;
 153                 goto out;
 154         }
 155
 156 #if defined(CONFIG_X86_64)
 157         asm volatile("pushq %%rax\n\t"
 158                 "movl 0(%%rax),%%edx\n\t"
 159                 "pushq %%rdx\n\t"
 160                 "movl 4(%%rax),%%ebx\n\t"
 161                 "movl 8(%%rax),%%ecx\n\t"
 162                 "movl 12(%%rax),%%edx\n\t"
 163                 "movl 16(%%rax),%%esi\n\t"
 164                 "movl 20(%%rax),%%edi\n\t"
 165                 "popq %%rax\n\t"
 166                 "out %%al,$0xb2\n\t"
 167                 "out %%al,$0x84\n\t"
 168                 "xchgq %%rax,(%%rsp)\n\t"
 169                 "movl %%ebx,4(%%rax)\n\t"
 170                 "movl %%ecx,8(%%rax)\n\t"
 171                 "movl %%edx,12(%%rax)\n\t"
 172                 "movl %%esi,16(%%rax)\n\t"
 173                 "movl %%edi,20(%%rax)\n\t"
 174                 "popq %%rdx\n\t"
 175                 "movl %%edx,0(%%rax)\n\t"
 176                 "pushfq\n\t"
 177                 "popq %%rax\n\t"
 178                 "andl $1,%%eax\n"
 179                 : "=a"(rc)
 180                 :    "a"(regs)
 181                 :    "%ebx", "%ecx", "%edx", "%esi", "%edi", "memory");
 182 #else
 183         asm volatile("pushl %%eax\n\t"
 184             "movl 0(%%eax),%%edx\n\t"
 185             "push %%edx\n\t"
 186             "movl 4(%%eax),%%ebx\n\t"
 187             "movl 8(%%eax),%%ecx\n\t"
 188             "movl 12(%%eax),%%edx\n\t"
 189             "movl 16(%%eax),%%esi\n\t"
 190             "movl 20(%%eax),%%edi\n\t"
 191             "popl %%eax\n\t"
 192             "out %%al,$0xb2\n\t"
 193             "out %%al,$0x84\n\t"
 194             "xchgl %%eax,(%%esp)\n\t"
 195             "movl %%ebx,4(%%eax)\n\t"
 196             "movl %%ecx,8(%%eax)\n\t"
 197             "movl %%edx,12(%%eax)\n\t"
 198             "movl %%esi,16(%%eax)\n\t"
 199             "movl %%edi,20(%%eax)\n\t"
 200             "popl %%edx\n\t"
 201             "movl %%edx,0(%%eax)\n\t"
 202             "lahf\n\t"
 203             "shrl $8,%%eax\n\t"
 204             "andl $1,%%eax\n"
 205             : "=a"(rc)
 206             :    "a"(regs)
 207             :    "%ebx", "%ecx", "%edx", "%esi", "%edi", "memory");
 208 #endif
 209         if (rc != 0 || (regs->eax & 0xffff) == 0xffff || regs->eax == eax)
 210                 rc = -EINVAL;
 211
 212 out:
 213         set_cpus_allowed_ptr(current, old_mask);
 214         free_cpumask_var(old_mask);
 215         return rc;
 216 }
 217
 218 /*
 219  * Read the Fn key status.
 220  */
 221 static int i8k_get_fn_status(void)
 222 {
 223         struct smm_regs regs = { .eax = I8K_SMM_FN_STATUS, };
 224         int rc;
 225
 226         rc = i8k_smm(&regs);
 227         if (rc < 0)
 228                 return rc;
 229
 230         switch ((regs.eax >> I8K_FN_SHIFT) & I8K_FN_MASK) {
 231         case I8K_FN_UP:
 232                 return I8K_VOL_UP;
 233         case I8K_FN_DOWN:
 234                 return I8K_VOL_DOWN;
 235         case I8K_FN_MUTE:
 236                 return I8K_VOL_MUTE;
 237         default:
 238                 return 0;
 239         }
 240 }
 241
 242 /*
 243  * Read the power status.
 244  */
 245 static int i8k_get_power_status(void)
 246 {
 247         struct smm_regs regs = { .eax = I8K_SMM_POWER_STATUS, };
 248         int rc;
 249
 250         rc = i8k_smm(&regs);
 251         if (rc < 0)
 252                 return rc;
 253
 254         return (regs.eax & 0xff) == I8K_POWER_AC ? I8K_AC : I8K_BATTERY;
 255 }
 256
 257 /*
 258  * Read the fan status.
 259  */
 260 static int i8k_get_fan_status(int fan)
 261 {
 262         struct smm_regs regs = { .eax = I8K_SMM_GET_FAN, };
 263
 264         regs.ebx = fan & 0xff;
 265         return i8k_smm(&regs) ? : regs.eax & 0xff;
 266 }
 267
 268 /*
 269  * Read the fan speed in RPM.
 270  */
 271 static int i8k_get_fan_speed(int fan)
 272 {
 273         struct smm_regs regs = { .eax = I8K_SMM_GET_SPEED, };
 274
 275         regs.ebx = fan & 0xff;
 276         return i8k_smm(&regs) ? : (regs.eax & 0xffff) * i8k_fan_mult;
 277 }
 278
 279 /*
 280  * Set the fan speed (off, low, high). Returns the new fan status.
 281  */
 282 static int i8k_set_fan(int fan, int speed)
 283 {
 284         struct smm_regs regs = { .eax = I8K_SMM_SET_FAN, };
 285
 286         speed = (speed < 0) ? 0 : ((speed > i8k_fan_max) ? i8k_fan_max : speed);
 287         regs.ebx = (fan & 0xff) | (speed << 8);
 288
 289         return i8k_smm(&regs) ? : i8k_get_fan_status(fan);
 290 }
 291
 292 static int i8k_get_temp_type(int sensor)
 293 {
 294         struct smm_regs regs = { .eax = I8K_SMM_GET_TEMP_TYPE, };
 295
 296         regs.ebx = sensor & 0xff;
 297         return i8k_smm(&regs) ? : regs.eax & 0xff;
 298 }
 299
 300 /*
 301  * Read the cpu temperature.
 302  */
 303 static int i8k_get_temp(int sensor)
 304 {
 305         struct smm_regs regs = { .eax = I8K_SMM_GET_TEMP, };
 306         int rc;
 307         int temp;
 308
 309 #ifdef I8K_TEMPERATURE_BUG
 310         static int prev[4] = { I8K_MAX_TEMP+1, I8K_MAX_TEMP+1, I8K_MAX_TEMP+1, I8K_MAX_TEMP+1 };
 311 #endif
 312         regs.ebx = sensor & 0xff;
 313         rc = i8k_smm(&regs);
 314         if (rc < 0)
 315                 return rc;
 316
 317         temp = regs.eax & 0xff;
 318
 319 #ifdef I8K_TEMPERATURE_BUG
 320         /*
 321          * Sometimes the temperature sensor returns 0x99, which is out of range.
 322          * In this case we return (once) the previous cached value. For example:
 323          # 1003655137 00000058 00005a4b
 324          # 1003655138 00000099 00003a80 <--- 0x99 = 153 degrees
 325          # 1003655139 00000054 00005c52
 326          */
 327         if (temp > I8K_MAX_TEMP) {
 328                 temp = prev[sensor];
 329                 prev[sensor] = I8K_MAX_TEMP+1;
 330         } else {
 331                 prev[sensor] = temp;
 332         }
 333         if (temp > I8K_MAX_TEMP)
 334                 return -ENODATA;
 335 #endif
 336
 337         return temp;
 338 }
 339
 340 static int i8k_get_dell_signature(int req_fn)
 341 {
 342         struct smm_regs regs = { .eax = req_fn, };
 343         int rc;
 344
 345         rc = i8k_smm(&regs);
 346         if (rc < 0)
 347                 return rc;
 348
 349         return regs.eax == 1145651527 && regs.edx == 1145392204 ? 0 : -1;
 350 }
 351
 352 static int
 353 i8k_ioctl_unlocked(struct file *fp, unsigned int cmd, unsigned long arg)
 354 {
 355         int val = 0;
 356         int speed;
 357         unsigned char buff[16];
 358         int __user *argp = (int __user *)arg;
 359
 360         if (!argp)
 361                 return -EINVAL;
 362
 363         switch (cmd) {
 364         case I8K_BIOS_VERSION:
 365                 val = (bios_version[0] << 16) |
 366                                 (bios_version[1] << 8) | bios_version[2];
 367                 break;
 368
 369         case I8K_MACHINE_ID:
 370                 memset(buff, 0, 16);
 371                 strlcpy(buff, i8k_get_dmi_data(DMI_PRODUCT_SERIAL),
 372                         sizeof(buff));
 373                 break;
 374
 375         case I8K_FN_STATUS:
 376                 val = i8k_get_fn_status();
 377                 break;
 378
 379         case I8K_POWER_STATUS:
 380                 val = i8k_get_power_status();
 381                 break;
 382
 383         case I8K_GET_TEMP:
 384                 val = i8k_get_temp(0);
 385                 break;
 386
 387         case I8K_GET_SPEED:
 388                 if (copy_from_user(&val, argp, sizeof(int)))
 389                         return -EFAULT;
 390
 391                 val = i8k_get_fan_speed(val);
 392                 break;
 393
 394         case I8K_GET_FAN:
 395                 if (copy_from_user(&val, argp, sizeof(int)))
 396                         return -EFAULT;
 397
 398                 val = i8k_get_fan_status(val);
 399                 break;
 400
 401         case I8K_SET_FAN:
 402                 if (restricted && !capable(CAP_SYS_ADMIN))
 403                         return -EPERM;
 404
 405                 if (copy_from_user(&val, argp, sizeof(int)))
 406                         return -EFAULT;
 407
 408                 if (copy_from_user(&speed, argp + 1, sizeof(int)))
 409                         return -EFAULT;
 410
 411                 val = i8k_set_fan(val, speed);
 412                 break;
 413
 414         default:
 415                 return -EINVAL;
 416         }
 417
 418         if (val < 0)
 419                 return val;
 420
 421         switch (cmd) {
 422         case I8K_BIOS_VERSION:
 423                 if (copy_to_user(argp, &val, 4))
 424                         return -EFAULT;
 425
 426                 break;
 427         case I8K_MACHINE_ID:
 428                 if (copy_to_user(argp, buff, 16))
 429                         return -EFAULT;
 430
 431                 break;
 432         default:
 433                 if (copy_to_user(argp, &val, sizeof(int)))
 434                         return -EFAULT;
 435
 436                 break;
 437         }
 438
 439         return 0;
 440 }
 441
 442 static long i8k_ioctl(struct file *fp, unsigned int cmd, unsigned long arg)
 443 {
 444         long ret;
 445
 446         mutex_lock(&i8k_mutex);
 447         ret = i8k_ioctl_unlocked(fp, cmd, arg);
 448         mutex_unlock(&i8k_mutex);
 449
 450         return ret;
 451 }
 452
 453 /*
 454  * Print the information for /proc/i8k.
 455  */
 456 static int i8k_proc_show(struct seq_file *seq, void *offset)
 457 {
 458         int fn_key, cpu_temp, ac_power;
 459         int left_fan, right_fan, left_speed, right_speed;
 460
 461         cpu_temp        = i8k_get_temp(0);                      /* 11100 µs */
 462         left_fan        = i8k_get_fan_status(I8K_FAN_LEFT);     /*   580 µs */
 463         right_fan       = i8k_get_fan_status(I8K_FAN_RIGHT);    /*   580 µs */
 464         left_speed      = i8k_get_fan_speed(I8K_FAN_LEFT);      /*   580 µs */
 465         right_speed     = i8k_get_fan_speed(I8K_FAN_RIGHT);     /*   580 µs */
 466         fn_key          = i8k_get_fn_status();                  /*   750 µs */
 467         if (power_status)
 468                 ac_power = i8k_get_power_status();              /* 14700 µs */
 469         else
 470                 ac_power = -1;
 471
 472         /*
 473          * Info:
 474          *
 475          * 1)  Format version (this will change if format changes)
 476          * 2)  BIOS version
 477          * 3)  BIOS machine ID
 478          * 4)  Cpu temperature
 479          * 5)  Left fan status
 480          * 6)  Right fan status
 481          * 7)  Left fan speed
 482          * 8)  Right fan speed
 483          * 9)  AC power
 484          * 10) Fn Key status
 485          */
 486         return seq_printf(seq, "%s %s %s %d %d %d %d %d %d %d\n",
 487                           I8K_PROC_FMT,
 488                           bios_version,
 489                           i8k_get_dmi_data(DMI_PRODUCT_SERIAL),
 490                           cpu_temp,
 491                           left_fan, right_fan, left_speed, right_speed,
 492                           ac_power, fn_key);
 493 }
 494
 495 static int i8k_open_fs(struct inode *inode, struct file *file)
 496 {
 497         return single_open(file, i8k_proc_show, NULL);
 498 }
 499
 500
 501 /*
 502  * Hwmon interface
 503  */
 504
 505 static ssize_t i8k_hwmon_show_temp_label(struct device *dev,
 506                                          struct device_attribute *devattr,
 507                                          char *buf)
 508 {
 509         static const char * const labels[] = {
 510                 "CPU",
 511                 "GPU",
 512                 "SODIMM",
 513                 "Other",
 514                 "Ambient",
 515                 "Other",
 516         };
 517         int index = to_sensor_dev_attr(devattr)->index;
 518         int type;
 519
 520         type = i8k_get_temp_type(index);
 521         if (type < 0)
 522                 return type;
 523         if (type >= ARRAY_SIZE(labels))
 524                 type = ARRAY_SIZE(labels) - 1;
 525         return sprintf(buf, "%s\n", labels[type]);
 526 }
 527
 528 static ssize_t i8k_hwmon_show_temp(struct device *dev,
 529                                    struct device_attribute *devattr,
 530                                    char *buf)
 531 {
 532         int index = to_sensor_dev_attr(devattr)->index;
 533         int temp;
 534
 535         temp = i8k_get_temp(index);
 536         if (temp < 0)
 537                 return temp;
 538         return sprintf(buf, "%d\n", temp * 1000);
 539 }
 540
 541 static ssize_t i8k_hwmon_show_fan(struct device *dev,
 542                                   struct device_attribute *devattr,
 543                                   char *buf)
 544 {
 545         int index = to_sensor_dev_attr(devattr)->index;
 546         int fan_speed;
 547
 548         fan_speed = i8k_get_fan_speed(index);
 549         if (fan_speed < 0)
 550                 return fan_speed;
 551         return sprintf(buf, "%d\n", fan_speed);
 552 }
 553
 554 static ssize_t i8k_hwmon_show_pwm(struct device *dev,
 555                                   struct device_attribute *devattr,
 556                                   char *buf)
 557 {
 558         int index = to_sensor_dev_attr(devattr)->index;
 559         int status;
 560
 561         status = i8k_get_fan_status(index);
 562         if (status < 0)
 563                 return -EIO;
 564         return sprintf(buf, "%d\n", clamp_val(status * i8k_pwm_mult, 0, 255));
 565 }
 566
 567 static ssize_t i8k_hwmon_set_pwm(struct device *dev,
 568                                  struct device_attribute *attr,
 569                                  const char *buf, size_t count)
 570 {
 571         int index = to_sensor_dev_attr(attr)->index;
 572         unsigned long val;
 573         int err;
 574
 575         err = kstrtoul(buf, 10, &val);
 576         if (err)
 577                 return err;
 578         val = clamp_val(DIV_ROUND_CLOSEST(val, i8k_pwm_mult), 0, i8k_fan_max);
 579
 580         mutex_lock(&i8k_mutex);
 581         err = i8k_set_fan(index, val);
 582         mutex_unlock(&i8k_mutex);
 583
 584         return err < 0 ? -EIO : count;
 585 }
 586
 587 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, i8k_hwmon_show_temp, NULL, 0);
 588 static SENSOR_DEVICE_ATTR(temp1_label, S_IRUGO, i8k_hwmon_show_temp_label, NULL,
 589                           0);
 590 static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, i8k_hwmon_show_temp, NULL, 1);
 591 static SENSOR_DEVICE_ATTR(temp2_label, S_IRUGO, i8k_hwmon_show_temp_label, NULL,
 592                           1);
 593 static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, i8k_hwmon_show_temp, NULL, 2);
 594 static SENSOR_DEVICE_ATTR(temp3_label, S_IRUGO, i8k_hwmon_show_temp_label, NULL,
 595                           2);
 596 static SENSOR_DEVICE_ATTR(temp4_input, S_IRUGO, i8k_hwmon_show_temp, NULL, 3);
 597 static SENSOR_DEVICE_ATTR(temp4_label, S_IRUGO, i8k_hwmon_show_temp_label, NULL,
 598                           3);
 599 static SENSOR_DEVICE_ATTR(fan1_input, S_IRUGO, i8k_hwmon_show_fan, NULL,
 600                           I8K_FAN_LEFT);
 601 static SENSOR_DEVICE_ATTR(pwm1, S_IRUGO | S_IWUSR, i8k_hwmon_show_pwm,
 602                           i8k_hwmon_set_pwm, I8K_FAN_LEFT);
 603 static SENSOR_DEVICE_ATTR(fan2_input, S_IRUGO, i8k_hwmon_show_fan, NULL,
 604                           I8K_FAN_RIGHT);
 605 static SENSOR_DEVICE_ATTR(pwm2, S_IRUGO | S_IWUSR, i8k_hwmon_show_pwm,
 606                           i8k_hwmon_set_pwm, I8K_FAN_RIGHT);
 607
 608 static struct attribute *i8k_attrs[] = {
 609         &sensor_dev_attr_temp1_input.dev_attr.attr,     /* 0 */
 610         &sensor_dev_attr_temp1_label.dev_attr.attr,     /* 1 */
 611         &sensor_dev_attr_temp2_input.dev_attr.attr,     /* 2 */
 612         &sensor_dev_attr_temp2_label.dev_attr.attr,     /* 3 */
 613         &sensor_dev_attr_temp3_input.dev_attr.attr,     /* 4 */
 614         &sensor_dev_attr_temp3_label.dev_attr.attr,     /* 5 */
 615         &sensor_dev_attr_temp4_input.dev_attr.attr,     /* 6 */
 616         &sensor_dev_attr_temp4_label.dev_attr.attr,     /* 7 */
 617         &sensor_dev_attr_fan1_input.dev_attr.attr,      /* 8 */
 618         &sensor_dev_attr_pwm1.dev_attr.attr,            /* 9 */
 619         &sensor_dev_attr_fan2_input.dev_attr.attr,      /* 10 */
 620         &sensor_dev_attr_pwm2.dev_attr.attr,            /* 11 */
 621         NULL
 622 };
 623
 624 static umode_t i8k_is_visible(struct kobject *kobj, struct attribute *attr,
 625                               int index)
 626 {
 627         if (index >= 0 && index <= 1 &&
 628             !(i8k_hwmon_flags & I8K_HWMON_HAVE_TEMP1))
 629                 return 0;
 630         if (index >= 2 && index <= 3 &&
 631             !(i8k_hwmon_flags & I8K_HWMON_HAVE_TEMP2))
 632                 return 0;
 633         if (index >= 4 && index <= 5 &&
 634             !(i8k_hwmon_flags & I8K_HWMON_HAVE_TEMP3))
 635                 return 0;
 636         if (index >= 6 && index <= 7 &&
 637             !(i8k_hwmon_flags & I8K_HWMON_HAVE_TEMP4))
 638                 return 0;
 639         if (index >= 8 && index <= 9 &&
 640             !(i8k_hwmon_flags & I8K_HWMON_HAVE_FAN1))
 641                 return 0;
 642         if (index >= 10 && index <= 11 &&
 643             !(i8k_hwmon_flags & I8K_HWMON_HAVE_FAN2))
 644                 return 0;
 645
 646         return attr->mode;
 647 }
 648
 649 static const struct attribute_group i8k_group = {
 650         .attrs = i8k_attrs,
 651         .is_visible = i8k_is_visible,
 652 };
 653 __ATTRIBUTE_GROUPS(i8k);
 654
 655 static int __init i8k_init_hwmon(void)
 656 {
 657         int err;
 658
 659         i8k_hwmon_flags = 0;
 660
 661         /* CPU temperature attributes, if temperature type is OK */
 662         err = i8k_get_temp_type(0);
 663         if (err >= 0)
 664                 i8k_hwmon_flags |= I8K_HWMON_HAVE_TEMP1;
 665         /* check for additional temperature sensors */
 666         err = i8k_get_temp_type(1);
 667         if (err >= 0)
 668                 i8k_hwmon_flags |= I8K_HWMON_HAVE_TEMP2;
 669         err = i8k_get_temp_type(2);
 670         if (err >= 0)
 671                 i8k_hwmon_flags |= I8K_HWMON_HAVE_TEMP3;
 672         err = i8k_get_temp_type(3);
 673         if (err >= 0)
 674                 i8k_hwmon_flags |= I8K_HWMON_HAVE_TEMP4;
 675
 676         /* Left fan attributes, if left fan is present */
 677         err = i8k_get_fan_status(I8K_FAN_LEFT);
 678         if (err >= 0)
 679                 i8k_hwmon_flags |= I8K_HWMON_HAVE_FAN1;
 680
 681         /* Right fan attributes, if right fan is present */
 682         err = i8k_get_fan_status(I8K_FAN_RIGHT);
 683         if (err >= 0)
 684                 i8k_hwmon_flags |= I8K_HWMON_HAVE_FAN2;
 685
 686         i8k_hwmon_dev = hwmon_device_register_with_groups(NULL, "i8k", NULL,
 687                                                           i8k_groups);
 688         if (IS_ERR(i8k_hwmon_dev)) {
 689                 err = PTR_ERR(i8k_hwmon_dev);
 690                 i8k_hwmon_dev = NULL;
 691                 pr_err("hwmon registration failed (%d)\n", err);
 692                 return err;
 693         }
 694         return 0;
 695 }
 696
 697 struct i8k_config_data {
 698         int fan_mult;
 699         int fan_max;
 700 };
 701
 702 enum i8k_configs {
 703         DELL_LATITUDE_D520,
 704         DELL_LATITUDE_E6540,
 705         DELL_PRECISION_490,
 706         DELL_STUDIO,
 707         DELL_XPS_M140,
 708 };
 709
 710 static const struct i8k_config_data i8k_config_data[] = {
 711         [DELL_LATITUDE_D520] = {
 712                 .fan_mult = 1,
 713                 .fan_max = I8K_FAN_TURBO,
 714         },
 715         [DELL_LATITUDE_E6540] = {
 716                 .fan_mult = 1,
 717                 .fan_max = I8K_FAN_HIGH,
 718         },
 719         [DELL_PRECISION_490] = {
 720                 .fan_mult = 1,
 721                 .fan_max = I8K_FAN_TURBO,
 722         },
 723         [DELL_STUDIO] = {
 724                 .fan_mult = 1,
 725                 .fan_max = I8K_FAN_HIGH,
 726         },
 727         [DELL_XPS_M140] = {
 728                 .fan_mult = 1,
 729                 .fan_max = I8K_FAN_HIGH,
 730         },
 731 };
 732
 733 static struct dmi_system_id i8k_dmi_table[] __initdata = {
 734         {
 735                 .ident = "Dell Inspiron",
 736                 .matches = {
 737                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer"),
 738                         DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron"),
 739                 },
 740         },
 741         {
 742                 .ident = "Dell Latitude",
 743                 .matches = {
 744                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer"),
 745                         DMI_MATCH(DMI_PRODUCT_NAME, "Latitude"),
 746                 },
 747         },
 748         {
 749                 .ident = "Dell Inspiron 2",
 750                 .matches = {
 751                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 752                         DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron"),
 753                 },
 754         },
 755         {
 756                 .ident = "Dell Latitude D520",
 757                 .matches = {
 758                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 759                         DMI_MATCH(DMI_PRODUCT_NAME, "Latitude D520"),
 760                 },
 761                 .driver_data = (void *)&i8k_config_data[DELL_LATITUDE_D520],
 762         },
 763         {
 764                 .ident = "Dell Latitude E6440",
 765                 .matches = {
 766                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 767                         DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6440"),
 768                 },
 769                 .driver_data = (void *)&i8k_config_data[DELL_LATITUDE_E6540],
 770         },
 771         {
 772                 .ident = "Dell Latitude E6540",
 773                 .matches = {
 774                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 775                         DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6540"),
 776                 },
 777                 .driver_data = (void *)&i8k_config_data[DELL_LATITUDE_E6540],
 778         },
 779         {
 780                 .ident = "Dell Latitude 2",
 781                 .matches = {
 782                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 783                         DMI_MATCH(DMI_PRODUCT_NAME, "Latitude"),
 784                 },
 785         },
 786         {       /* UK Inspiron 6400  */
 787                 .ident = "Dell Inspiron 3",
 788                 .matches = {
 789                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 790                         DMI_MATCH(DMI_PRODUCT_NAME, "MM061"),
 791                 },
 792         },
 793         {
 794                 .ident = "Dell Inspiron 3",
 795                 .matches = {
 796                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 797                         DMI_MATCH(DMI_PRODUCT_NAME, "MP061"),
 798                 },
 799         },
 800         {
 801                 .ident = "Dell Precision 490",
 802                 .matches = {
 803                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 804                         DMI_MATCH(DMI_PRODUCT_NAME,
 805                                   "Precision WorkStation 490"),
 806                 },
 807                 .driver_data = (void *)&i8k_config_data[DELL_PRECISION_490],
 808         },
 809         {
 810                 .ident = "Dell Precision",
 811                 .matches = {
 812                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 813                         DMI_MATCH(DMI_PRODUCT_NAME, "Precision"),
 814                 },
 815         },
 816         {
 817                 .ident = "Dell Vostro",
 818                 .matches = {
 819                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 820                         DMI_MATCH(DMI_PRODUCT_NAME, "Vostro"),
 821                 },
 822         },
 823         {
 824                 .ident = "Dell XPS421",
 825                 .matches = {
 826                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 827                         DMI_MATCH(DMI_PRODUCT_NAME, "XPS L421X"),
 828                 },
 829         },
 830         {
 831                 .ident = "Dell Studio",
 832                 .matches = {
 833                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 834                         DMI_MATCH(DMI_PRODUCT_NAME, "Studio"),
 835                 },
 836                 .driver_data = (void *)&i8k_config_data[DELL_STUDIO],
 837         },
 838         {
 839                 .ident = "Dell XPS M140",
 840                 .matches = {
 841                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 842                         DMI_MATCH(DMI_PRODUCT_NAME, "MXC051"),
 843                 },
 844                 .driver_data = (void *)&i8k_config_data[DELL_XPS_M140],
 845         },
 846         { }
 847 };
 848
 849 MODULE_DEVICE_TABLE(dmi, i8k_dmi_table);
 850
 851 /*
 852  * Probe for the presence of a supported laptop.
 853  */
 854 static int __init i8k_probe(void)
 855 {
 856         const struct dmi_system_id *id;
 857
 858         /*
 859          * Get DMI information
 860          */
 861         if (!dmi_check_system(i8k_dmi_table)) {
 862                 if (!ignore_dmi && !force)
 863                         return -ENODEV;
 864
 865                 pr_info("not running on a supported Dell system.\n");
 866                 pr_info("vendor=%s, model=%s, version=%s\n",
 867                         i8k_get_dmi_data(DMI_SYS_VENDOR),
 868                         i8k_get_dmi_data(DMI_PRODUCT_NAME),
 869                         i8k_get_dmi_data(DMI_BIOS_VERSION));
 870         }
 871
 872         strlcpy(bios_version, i8k_get_dmi_data(DMI_BIOS_VERSION),
 873                 sizeof(bios_version));
 874
 875         /*
 876          * Get SMM Dell signature
 877          */
 878         if (i8k_get_dell_signature(I8K_SMM_GET_DELL_SIG1) &&
 879             i8k_get_dell_signature(I8K_SMM_GET_DELL_SIG2)) {
 880                 pr_err("unable to get SMM Dell signature\n");
 881                 if (!force)
 882                         return -ENODEV;
 883         }
 884
 885         i8k_fan_mult = fan_mult;
 886         i8k_fan_max = fan_max ? : I8K_FAN_HIGH; /* Must not be 0 */
 887         id = dmi_first_match(i8k_dmi_table);
 888         if (id && id->driver_data) {
 889                 const struct i8k_config_data *conf = id->driver_data;
 890
 891                 if (fan_mult == I8K_FAN_MULT && conf->fan_mult)
 892                         i8k_fan_mult = conf->fan_mult;
 893                 if (fan_max == I8K_FAN_HIGH && conf->fan_max)
 894                         i8k_fan_max = conf->fan_max;
 895         }
 896         i8k_pwm_mult = DIV_ROUND_UP(255, i8k_fan_max);
 897
 898         return 0;
 899 }
 900
 901 static int __init i8k_init(void)
 902 {
 903         struct proc_dir_entry *proc_i8k;
 904         int err;
 905
 906         /* Are we running on an supported laptop? */
 907         if (i8k_probe())
 908                 return -ENODEV;
 909
 910         /* Register the proc entry */
 911         proc_i8k = proc_create("i8k", 0, NULL, &i8k_fops);
 912         if (!proc_i8k)
 913                 return -ENOENT;
 914
 915         err = i8k_init_hwmon();
 916         if (err)
 917                 goto exit_remove_proc;
 918
 919         return 0;
 920
 921  exit_remove_proc:
 922         remove_proc_entry("i8k", NULL);
 923         return err;
 924 }
 925
 926 static void __exit i8k_exit(void)
 927 {
 928         hwmon_device_unregister(i8k_hwmon_dev);
 929         remove_proc_entry("i8k", NULL);
 930 }
 931
 932 module_init(i8k_init);
 933 module_exit(i8k_exit);