drivers/hwmon/applesmc.c

   1 /*
   2  * drivers/hwmon/applesmc.c - driver for Apple's SMC (accelerometer, temperature
   3  * sensors, fan control, keyboard backlight control) used in Intel-based Apple
   4  * computers.
   5  *
   6  * Copyright (C) 2007 Nicolas Boichat <nicolas@boichat.ch>
   7  * Copyright (C) 2010 Henrik Rydberg <rydberg@euromail.se>
   8  *
   9  * Based on hdaps.c driver:
  10  * Copyright (C) 2005 Robert Love <rml@novell.com>
  11  * Copyright (C) 2005 Jesper Juhl <jesper.juhl@gmail.com>
  12  *
  13  * Fan control based on smcFanControl:
  14  * Copyright (C) 2006 Hendrik Holtmann <holtmann@mac.com>
  15  *
  16  * This program is free software; you can redistribute it and/or modify it
  17  * under the terms of the GNU General Public License v2 as published by the
  18  * Free Software Foundation.
  19  *
  20  * This program is distributed in the hope that it will be useful, but WITHOUT
  21  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  22  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  23  * more details.
  24  *
  25  * You should have received a copy of the GNU General Public License along with
  26  * this program; if not, write to the Free Software Foundation, Inc.,
  27  * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
  28  */
  29
  30 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  31
  32 #include <linux/delay.h>
  33 #include <linux/platform_device.h>
  34 #include <linux/input-polldev.h>
  35 #include <linux/kernel.h>
  36 #include <linux/slab.h>
  37 #include <linux/module.h>
  38 #include <linux/timer.h>
  39 #include <linux/dmi.h>
  40 #include <linux/mutex.h>
  41 #include <linux/hwmon-sysfs.h>
  42 #include <linux/io.h>
  43 #include <linux/leds.h>
  44 #include <linux/hwmon.h>
  45 #include <linux/workqueue.h>
  46
  47 /* data port used by Apple SMC */
  48 #define APPLESMC_DATA_PORT      0x300
  49 /* command/status port used by Apple SMC */
  50 #define APPLESMC_CMD_PORT       0x304
  51
  52 #define APPLESMC_NR_PORTS       32 /* 0x300-0x31f */
  53
  54 #define APPLESMC_MAX_DATA_LENGTH 32
  55
  56 /* wait up to 32 ms for a status change. */
  57 #define APPLESMC_MIN_WAIT       0x0040
  58 #define APPLESMC_MAX_WAIT       0x8000
  59
  60 #define APPLESMC_STATUS_MASK    0x0f
  61 #define APPLESMC_READ_CMD       0x10
  62 #define APPLESMC_WRITE_CMD      0x11
  63 #define APPLESMC_GET_KEY_BY_INDEX_CMD   0x12
  64 #define APPLESMC_GET_KEY_TYPE_CMD       0x13
  65
  66 #define KEY_COUNT_KEY           "#KEY" /* r-o ui32 */
  67
  68 #define LIGHT_SENSOR_LEFT_KEY   "ALV0" /* r-o {alv (6-10 bytes) */
  69 #define LIGHT_SENSOR_RIGHT_KEY  "ALV1" /* r-o {alv (6-10 bytes) */
  70 #define BACKLIGHT_KEY           "LKSB" /* w-o {lkb (2 bytes) */
  71
  72 #define CLAMSHELL_KEY           "MSLD" /* r-o ui8 (unused) */
  73
  74 #define MOTION_SENSOR_X_KEY     "MO_X" /* r-o sp78 (2 bytes) */
  75 #define MOTION_SENSOR_Y_KEY     "MO_Y" /* r-o sp78 (2 bytes) */
  76 #define MOTION_SENSOR_Z_KEY     "MO_Z" /* r-o sp78 (2 bytes) */
  77 #define MOTION_SENSOR_KEY       "MOCN" /* r/w ui16 */
  78
  79 #define FANS_COUNT              "FNum" /* r-o ui8 */
  80 #define FANS_MANUAL             "FS! " /* r-w ui16 */
  81 #define FAN_ID_FMT              "F%dID" /* r-o char[16] */
  82
  83 /* List of keys used to read/write fan speeds */
  84 static const char *const fan_speed_fmt[] = {
  85         "F%dAc",                /* actual speed */
  86         "F%dMn",                /* minimum speed (rw) */
  87         "F%dMx",                /* maximum speed */
  88         "F%dSf",                /* safe speed - not all models */
  89         "F%dTg",                /* target speed (manual: rw) */
  90 };
  91
  92 #define INIT_TIMEOUT_MSECS      5000    /* wait up to 5s for device init ... */
  93 #define INIT_WAIT_MSECS         50      /* ... in 50ms increments */
  94
  95 #define APPLESMC_POLL_INTERVAL  50      /* msecs */
  96 #define APPLESMC_INPUT_FUZZ     4       /* input event threshold */
  97 #define APPLESMC_INPUT_FLAT     4
  98
  99 #define SENSOR_X 0
 100 #define SENSOR_Y 1
 101 #define SENSOR_Z 2
 102
 103 #define to_index(attr) (to_sensor_dev_attr(attr)->index & 0xffff)
 104 #define to_option(attr) (to_sensor_dev_attr(attr)->index >> 16)
 105
 106 /* Dynamic device node attributes */
 107 struct applesmc_dev_attr {
 108         struct sensor_device_attribute sda;     /* hwmon attributes */
 109         char name[32];                          /* room for node file name */
 110 };
 111
 112 /* Dynamic device node group */
 113 struct applesmc_node_group {
 114         char *format;                           /* format string */
 115         void *show;                             /* show function */
 116         void *store;                            /* store function */
 117         int option;                             /* function argument */
 118         struct applesmc_dev_attr *nodes;        /* dynamic node array */
 119 };
 120
 121 /* AppleSMC entry - cached register information */
 122 struct applesmc_entry {
 123         char key[5];            /* four-letter key code */
 124         u8 valid;               /* set when entry is successfully read once */
 125         u8 len;                 /* bounded by APPLESMC_MAX_DATA_LENGTH */
 126         char type[5];           /* four-letter type code */
 127         u8 flags;               /* 0x10: func; 0x40: write; 0x80: read */
 128 };
 129
 130 /* Register lookup and registers common to all SMCs */
 131 static struct applesmc_registers {
 132         struct mutex mutex;             /* register read/write mutex */
 133         unsigned int key_count;         /* number of SMC registers */
 134         unsigned int fan_count;         /* number of fans */
 135         unsigned int temp_count;        /* number of temperature registers */
 136         unsigned int temp_begin;        /* temperature lower index bound */
 137         unsigned int temp_end;          /* temperature upper index bound */
 138         int num_light_sensors;          /* number of light sensors */
 139         bool has_accelerometer;         /* has motion sensor */
 140         bool has_key_backlight;         /* has keyboard backlight */
 141         bool init_complete;             /* true when fully initialized */
 142         struct applesmc_entry *cache;   /* cached key entries */
 143 } smcreg = {
 144         .mutex = __MUTEX_INITIALIZER(smcreg.mutex),
 145 };
 146
 147 static const int debug;
 148 static struct platform_device *pdev;
 149 static s16 rest_x;
 150 static s16 rest_y;
 151 static u8 backlight_state[2];
 152
 153 static struct device *hwmon_dev;
 154 static struct input_polled_dev *applesmc_idev;
 155
 156 /*
 157  * Last index written to key_at_index sysfs file, and value to use for all other
 158  * key_at_index_* sysfs files.
 159  */
 160 static unsigned int key_at_index;
 161
 162 static struct workqueue_struct *applesmc_led_wq;
 163
 164 /*
 165  * __wait_status - Wait up to 32ms for the status port to get a certain value
 166  * (masked with 0x0f), returning zero if the value is obtained.  Callers must
 167  * hold applesmc_lock.
 168  */
 169 static int __wait_status(u8 val)
 170 {
 171         int us;
 172
 173         val = val & APPLESMC_STATUS_MASK;
 174
 175         for (us = APPLESMC_MIN_WAIT; us < APPLESMC_MAX_WAIT; us <<= 1) {
 176                 udelay(us);
 177                 if ((inb(APPLESMC_CMD_PORT) & APPLESMC_STATUS_MASK) == val)
 178                         return 0;
 179         }
 180
 181         return -EIO;
 182 }
 183
 184 /*
 185  * special treatment of command port - on newer macbooks, it seems necessary
 186  * to resend the command byte before polling the status again. Callers must
 187  * hold applesmc_lock.
 188  */
 189 static int send_command(u8 cmd)
 190 {
 191         int us;
 192         for (us = APPLESMC_MIN_WAIT; us < APPLESMC_MAX_WAIT; us <<= 1) {
 193                 outb(cmd, APPLESMC_CMD_PORT);
 194                 udelay(us);
 195                 if ((inb(APPLESMC_CMD_PORT) & APPLESMC_STATUS_MASK) == 0x0c)
 196                         return 0;
 197         }
 198         return -EIO;
 199 }
 200
 201 static int send_argument(const char *key)
 202 {
 203         int i;
 204
 205         for (i = 0; i < 4; i++) {
 206                 outb(key[i], APPLESMC_DATA_PORT);
 207                 if (__wait_status(0x04))
 208                         return -EIO;
 209         }
 210         return 0;
 211 }
 212
 213 static int read_smc(u8 cmd, const char *key, u8 *buffer, u8 len)
 214 {
 215         int i;
 216
 217         if (send_command(cmd) || send_argument(key)) {
 218                 pr_warn("%s: read arg fail\n", key);
 219                 return -EIO;
 220         }
 221
 222         outb(len, APPLESMC_DATA_PORT);
 223
 224         for (i = 0; i < len; i++) {
 225                 if (__wait_status(0x05)) {
 226                         pr_warn("%s: read data fail\n", key);
 227                         return -EIO;
 228                 }
 229                 buffer[i] = inb(APPLESMC_DATA_PORT);
 230         }
 231
 232         return 0;
 233 }
 234
 235 static int write_smc(u8 cmd, const char *key, const u8 *buffer, u8 len)
 236 {
 237         int i;
 238
 239         if (send_command(cmd) || send_argument(key)) {
 240                 pr_warn("%s: write arg fail\n", key);
 241                 return -EIO;
 242         }
 243
 244         outb(len, APPLESMC_DATA_PORT);
 245
 246         for (i = 0; i < len; i++) {
 247                 if (__wait_status(0x04)) {
 248                         pr_warn("%s: write data fail\n", key);
 249                         return -EIO;
 250                 }
 251                 outb(buffer[i], APPLESMC_DATA_PORT);
 252         }
 253
 254         return 0;
 255 }
 256
 257 static int read_register_count(unsigned int *count)
 258 {
 259         __be32 be;
 260         int ret;
 261
 262         ret = read_smc(APPLESMC_READ_CMD, KEY_COUNT_KEY, (u8 *)&be, 4);
 263         if (ret)
 264                 return ret;
 265
 266         *count = be32_to_cpu(be);
 267         return 0;
 268 }
 269
 270 /*
 271  * Serialized I/O
 272  *
 273  * Returns zero on success or a negative error on failure.
 274  * All functions below are concurrency safe - callers should NOT hold lock.
 275  */
 276
 277 static int applesmc_read_entry(const struct applesmc_entry *entry,
 278                                u8 *buf, u8 len)
 279 {
 280         int ret;
 281
 282         if (entry->len != len)
 283                 return -EINVAL;
 284         mutex_lock(&smcreg.mutex);
 285         ret = read_smc(APPLESMC_READ_CMD, entry->key, buf, len);
 286         mutex_unlock(&smcreg.mutex);
 287
 288         return ret;
 289 }
 290
 291 static int applesmc_write_entry(const struct applesmc_entry *entry,
 292                                 const u8 *buf, u8 len)
 293 {
 294         int ret;
 295
 296         if (entry->len != len)
 297                 return -EINVAL;
 298         mutex_lock(&smcreg.mutex);
 299         ret = write_smc(APPLESMC_WRITE_CMD, entry->key, buf, len);
 300         mutex_unlock(&smcreg.mutex);
 301         return ret;
 302 }
 303
 304 static const struct applesmc_entry *applesmc_get_entry_by_index(int index)
 305 {
 306         struct applesmc_entry *cache = &smcreg.cache[index];
 307         u8 key[4], info[6];
 308         __be32 be;
 309         int ret = 0;
 310
 311         if (cache->valid)
 312                 return cache;
 313
 314         mutex_lock(&smcreg.mutex);
 315
 316         if (cache->valid)
 317                 goto out;
 318         be = cpu_to_be32(index);
 319         ret = read_smc(APPLESMC_GET_KEY_BY_INDEX_CMD, (u8 *)&be, key, 4);
 320         if (ret)
 321                 goto out;
 322         ret = read_smc(APPLESMC_GET_KEY_TYPE_CMD, key, info, 6);
 323         if (ret)
 324                 goto out;
 325
 326         memcpy(cache->key, key, 4);
 327         cache->len = info[0];
 328         memcpy(cache->type, &info[1], 4);
 329         cache->flags = info[5];
 330         cache->valid = 1;
 331
 332 out:
 333         mutex_unlock(&smcreg.mutex);
 334         if (ret)
 335                 return ERR_PTR(ret);
 336         return cache;
 337 }
 338
 339 static int applesmc_get_lower_bound(unsigned int *lo, const char *key)
 340 {
 341         int begin = 0, end = smcreg.key_count;
 342         const struct applesmc_entry *entry;
 343
 344         while (begin != end) {
 345                 int middle = begin + (end - begin) / 2;
 346                 entry = applesmc_get_entry_by_index(middle);
 347                 if (IS_ERR(entry))
 348                         return PTR_ERR(entry);
 349                 if (strcmp(entry->key, key) < 0)
 350                         begin = middle + 1;
 351                 else
 352                         end = middle;
 353         }
 354
 355         *lo = begin;
 356         return 0;
 357 }
 358
 359 static int applesmc_get_upper_bound(unsigned int *hi, const char *key)
 360 {
 361         int begin = 0, end = smcreg.key_count;
 362         const struct applesmc_entry *entry;
 363
 364         while (begin != end) {
 365                 int middle = begin + (end - begin) / 2;
 366                 entry = applesmc_get_entry_by_index(middle);
 367                 if (IS_ERR(entry))
 368                         return PTR_ERR(entry);
 369                 if (strcmp(key, entry->key) < 0)
 370                         end = middle;
 371                 else
 372                         begin = middle + 1;
 373         }
 374
 375         *hi = begin;
 376         return 0;
 377 }
 378
 379 static const struct applesmc_entry *applesmc_get_entry_by_key(const char *key)
 380 {
 381         int begin, end;
 382         int ret;
 383
 384         ret = applesmc_get_lower_bound(&begin, key);
 385         if (ret)
 386                 return ERR_PTR(ret);
 387         ret = applesmc_get_upper_bound(&end, key);
 388         if (ret)
 389                 return ERR_PTR(ret);
 390         if (end - begin != 1)
 391                 return ERR_PTR(-EINVAL);
 392
 393         return applesmc_get_entry_by_index(begin);
 394 }
 395
 396 static int applesmc_read_key(const char *key, u8 *buffer, u8 len)
 397 {
 398         const struct applesmc_entry *entry;
 399
 400         entry = applesmc_get_entry_by_key(key);
 401         if (IS_ERR(entry))
 402                 return PTR_ERR(entry);
 403
 404         return applesmc_read_entry(entry, buffer, len);
 405 }
 406
 407 static int applesmc_write_key(const char *key, const u8 *buffer, u8 len)
 408 {
 409         const struct applesmc_entry *entry;
 410
 411         entry = applesmc_get_entry_by_key(key);
 412         if (IS_ERR(entry))
 413                 return PTR_ERR(entry);
 414
 415         return applesmc_write_entry(entry, buffer, len);
 416 }
 417
 418 static int applesmc_has_key(const char *key, bool *value)
 419 {
 420         const struct applesmc_entry *entry;
 421
 422         entry = applesmc_get_entry_by_key(key);
 423         if (IS_ERR(entry) && PTR_ERR(entry) != -EINVAL)
 424                 return PTR_ERR(entry);
 425
 426         *value = !IS_ERR(entry);
 427         return 0;
 428 }
 429
 430 /*
 431  * applesmc_read_motion_sensor - Read motion sensor (X, Y or Z).
 432  */
 433 static int applesmc_read_motion_sensor(int index, s16 *value)
 434 {
 435         u8 buffer[2];
 436         int ret;
 437
 438         switch (index) {
 439         case SENSOR_X:
 440                 ret = applesmc_read_key(MOTION_SENSOR_X_KEY, buffer, 2);
 441                 break;
 442         case SENSOR_Y:
 443                 ret = applesmc_read_key(MOTION_SENSOR_Y_KEY, buffer, 2);
 444                 break;
 445         case SENSOR_Z:
 446                 ret = applesmc_read_key(MOTION_SENSOR_Z_KEY, buffer, 2);
 447                 break;
 448         default:
 449                 ret = -EINVAL;
 450         }
 451
 452         *value = ((s16)buffer[0] << 8) | buffer[1];
 453
 454         return ret;
 455 }
 456
 457 /*
 458  * applesmc_device_init - initialize the accelerometer.  Can sleep.
 459  */
 460 static void applesmc_device_init(void)
 461 {
 462         int total;
 463         u8 buffer[2];
 464
 465         if (!smcreg.has_accelerometer)
 466                 return;
 467
 468         for (total = INIT_TIMEOUT_MSECS; total > 0; total -= INIT_WAIT_MSECS) {
 469                 if (!applesmc_read_key(MOTION_SENSOR_KEY, buffer, 2) &&
 470                                 (buffer[0] != 0x00 || buffer[1] != 0x00))
 471                         return;
 472                 buffer[0] = 0xe0;
 473                 buffer[1] = 0x00;
 474                 applesmc_write_key(MOTION_SENSOR_KEY, buffer, 2);
 475                 msleep(INIT_WAIT_MSECS);
 476         }
 477
 478         pr_warn("failed to init the device\n");
 479 }
 480
 481 /*
 482  * applesmc_init_smcreg_try - Try to initialize register cache. Idempotent.
 483  */
 484 static int applesmc_init_smcreg_try(void)
 485 {
 486         struct applesmc_registers *s = &smcreg;
 487         bool left_light_sensor, right_light_sensor;
 488         u8 tmp[1];
 489         int ret;
 490
 491         if (s->init_complete)
 492                 return 0;
 493
 494         ret = read_register_count(&s->key_count);
 495         if (ret)
 496                 return ret;
 497
 498         if (!s->cache)
 499                 s->cache = kcalloc(s->key_count, sizeof(*s->cache), GFP_KERNEL);
 500         if (!s->cache)
 501                 return -ENOMEM;
 502
 503         ret = applesmc_read_key(FANS_COUNT, tmp, 1);
 504         if (ret)
 505                 return ret;
 506         s->fan_count = tmp[0];
 507
 508         ret = applesmc_get_lower_bound(&s->temp_begin, "T");
 509         if (ret)
 510                 return ret;
 511         ret = applesmc_get_lower_bound(&s->temp_end, "U");
 512         if (ret)
 513                 return ret;
 514         s->temp_count = s->temp_end - s->temp_begin;
 515
 516         ret = applesmc_has_key(LIGHT_SENSOR_LEFT_KEY, &left_light_sensor);
 517         if (ret)
 518                 return ret;
 519         ret = applesmc_has_key(LIGHT_SENSOR_RIGHT_KEY, &right_light_sensor);
 520         if (ret)
 521                 return ret;
 522         ret = applesmc_has_key(MOTION_SENSOR_KEY, &s->has_accelerometer);
 523         if (ret)
 524                 return ret;
 525         ret = applesmc_has_key(BACKLIGHT_KEY, &s->has_key_backlight);
 526         if (ret)
 527                 return ret;
 528
 529         s->num_light_sensors = left_light_sensor + right_light_sensor;
 530         s->init_complete = true;
 531
 532         pr_info("key=%d fan=%d temp=%d acc=%d lux=%d kbd=%d\n",
 533                s->key_count, s->fan_count, s->temp_count,
 534                s->has_accelerometer,
 535                s->num_light_sensors,
 536                s->has_key_backlight);
 537
 538         return 0;
 539 }
 540
 541 /*
 542  * applesmc_init_smcreg - Initialize register cache.
 543  *
 544  * Retries until initialization is successful, or the operation times out.
 545  *
 546  */
 547 static int applesmc_init_smcreg(void)
 548 {
 549         int ms, ret;
 550
 551         for (ms = 0; ms < INIT_TIMEOUT_MSECS; ms += INIT_WAIT_MSECS) {
 552                 ret = applesmc_init_smcreg_try();
 553                 if (!ret) {
 554                         if (ms)
 555                                 pr_info("init_smcreg() took %d ms\n", ms);
 556                         return 0;
 557                 }
 558                 msleep(INIT_WAIT_MSECS);
 559         }
 560
 561         kfree(smcreg.cache);
 562         smcreg.cache = NULL;
 563
 564         return ret;
 565 }
 566
 567 static void applesmc_destroy_smcreg(void)
 568 {
 569         kfree(smcreg.cache);
 570         smcreg.cache = NULL;
 571         smcreg.init_complete = false;
 572 }
 573
 574 /* Device model stuff */
 575 static int applesmc_probe(struct platform_device *dev)
 576 {
 577         int ret;
 578
 579         ret = applesmc_init_smcreg();
 580         if (ret)
 581                 return ret;
 582
 583         applesmc_device_init();
 584
 585         return 0;
 586 }
 587
 588 /* Synchronize device with memorized backlight state */
 589 static int applesmc_pm_resume(struct device *dev)
 590 {
 591         if (smcreg.has_key_backlight)
 592                 applesmc_write_key(BACKLIGHT_KEY, backlight_state, 2);
 593         return 0;
 594 }
 595
 596 /* Reinitialize device on resume from hibernation */
 597 static int applesmc_pm_restore(struct device *dev)
 598 {
 599         applesmc_device_init();
 600         return applesmc_pm_resume(dev);
 601 }
 602
 603 static const struct dev_pm_ops applesmc_pm_ops = {
 604         .resume = applesmc_pm_resume,
 605         .restore = applesmc_pm_restore,
 606 };
 607
 608 static struct platform_driver applesmc_driver = {
 609         .probe = applesmc_probe,
 610         .driver = {
 611                 .name = "applesmc",
 612                 .owner = THIS_MODULE,
 613                 .pm = &applesmc_pm_ops,
 614         },
 615 };
 616
 617 /*
 618  * applesmc_calibrate - Set our "resting" values.  Callers must
 619  * hold applesmc_lock.
 620  */
 621 static void applesmc_calibrate(void)
 622 {
 623         applesmc_read_motion_sensor(SENSOR_X, &rest_x);
 624         applesmc_read_motion_sensor(SENSOR_Y, &rest_y);
 625         rest_x = -rest_x;
 626 }
 627
 628 static void applesmc_idev_poll(struct input_polled_dev *dev)
 629 {
 630         struct input_dev *idev = dev->input;
 631         s16 x, y;
 632
 633         if (applesmc_read_motion_sensor(SENSOR_X, &x))
 634                 return;
 635         if (applesmc_read_motion_sensor(SENSOR_Y, &y))
 636                 return;
 637
 638         x = -x;
 639         input_report_abs(idev, ABS_X, x - rest_x);
 640         input_report_abs(idev, ABS_Y, y - rest_y);
 641         input_sync(idev);
 642 }
 643
 644 /* Sysfs Files */
 645
 646 static ssize_t applesmc_name_show(struct device *dev,
 647                                    struct device_attribute *attr, char *buf)
 648 {
 649         return snprintf(buf, PAGE_SIZE, "applesmc\n");
 650 }
 651
 652 static ssize_t applesmc_position_show(struct device *dev,
 653                                    struct device_attribute *attr, char *buf)
 654 {
 655         int ret;
 656         s16 x, y, z;
 657
 658         ret = applesmc_read_motion_sensor(SENSOR_X, &x);
 659         if (ret)
 660                 goto out;
 661         ret = applesmc_read_motion_sensor(SENSOR_Y, &y);
 662         if (ret)
 663                 goto out;
 664         ret = applesmc_read_motion_sensor(SENSOR_Z, &z);
 665         if (ret)
 666                 goto out;
 667
 668 out:
 669         if (ret)
 670                 return ret;
 671         else
 672                 return snprintf(buf, PAGE_SIZE, "(%d,%d,%d)\n", x, y, z);
 673 }
 674
 675 static ssize_t applesmc_light_show(struct device *dev,
 676                                 struct device_attribute *attr, char *sysfsbuf)
 677 {
 678         const struct applesmc_entry *entry;
 679         static int data_length;
 680         int ret;
 681         u8 left = 0, right = 0;
 682         u8 buffer[10];
 683
 684         if (!data_length) {
 685                 entry = applesmc_get_entry_by_key(LIGHT_SENSOR_LEFT_KEY);
 686                 if (IS_ERR(entry))
 687                         return PTR_ERR(entry);
 688                 if (entry->len > 10)
 689                         return -ENXIO;
 690                 data_length = entry->len;
 691                 pr_info("light sensor data length set to %d\n", data_length);
 692         }
 693
 694         ret = applesmc_read_key(LIGHT_SENSOR_LEFT_KEY, buffer, data_length);
 695         /* newer macbooks report a single 10-bit bigendian value */
 696         if (data_length == 10) {
 697                 left = be16_to_cpu(*(__be16 *)(buffer + 6)) >> 2;
 698                 goto out;
 699         }
 700         left = buffer[2];
 701         if (ret)
 702                 goto out;
 703         ret = applesmc_read_key(LIGHT_SENSOR_RIGHT_KEY, buffer, data_length);
 704         right = buffer[2];
 705
 706 out:
 707         if (ret)
 708                 return ret;
 709         else
 710                 return snprintf(sysfsbuf, PAGE_SIZE, "(%d,%d)\n", left, right);
 711 }
 712
 713 /* Displays sensor key as label */
 714 static ssize_t applesmc_show_sensor_label(struct device *dev,
 715                         struct device_attribute *devattr, char *sysfsbuf)
 716 {
 717         int index = smcreg.temp_begin + to_index(devattr);
 718         const struct applesmc_entry *entry;
 719
 720         entry = applesmc_get_entry_by_index(index);
 721         if (IS_ERR(entry))
 722                 return PTR_ERR(entry);
 723
 724         return snprintf(sysfsbuf, PAGE_SIZE, "%s\n", entry->key);
 725 }
 726
 727 /* Displays degree Celsius * 1000 */
 728 static ssize_t applesmc_show_temperature(struct device *dev,
 729                         struct device_attribute *devattr, char *sysfsbuf)
 730 {
 731         int index = smcreg.temp_begin + to_index(devattr);
 732         const struct applesmc_entry *entry;
 733         int ret;
 734         u8 buffer[2];
 735         unsigned int temp;
 736
 737         entry = applesmc_get_entry_by_index(index);
 738         if (IS_ERR(entry))
 739                 return PTR_ERR(entry);
 740         if (entry->len > 2)
 741                 return -EINVAL;
 742
 743         ret = applesmc_read_entry(entry, buffer, entry->len);
 744         if (ret)
 745                 return ret;
 746
 747         if (entry->len == 2) {
 748                 temp = buffer[0] * 1000;
 749                 temp += (buffer[1] >> 6) * 250;
 750         } else {
 751                 temp = buffer[0] * 4000;
 752         }
 753
 754         return snprintf(sysfsbuf, PAGE_SIZE, "%u\n", temp);
 755 }
 756
 757 static ssize_t applesmc_show_fan_speed(struct device *dev,
 758                                 struct device_attribute *attr, char *sysfsbuf)
 759 {
 760         int ret;
 761         unsigned int speed = 0;
 762         char newkey[5];
 763         u8 buffer[2];
 764
 765         sprintf(newkey, fan_speed_fmt[to_option(attr)], to_index(attr));
 766
 767         ret = applesmc_read_key(newkey, buffer, 2);
 768         speed = ((buffer[0] << 8 | buffer[1]) >> 2);
 769
 770         if (ret)
 771                 return ret;
 772         else
 773                 return snprintf(sysfsbuf, PAGE_SIZE, "%u\n", speed);
 774 }
 775
 776 static ssize_t applesmc_store_fan_speed(struct device *dev,
 777                                         struct device_attribute *attr,
 778                                         const char *sysfsbuf, size_t count)
 779 {
 780         int ret;
 781         unsigned long speed;
 782         char newkey[5];
 783         u8 buffer[2];
 784
 785         if (strict_strtoul(sysfsbuf, 10, &speed) < 0 || speed >= 0x4000)
 786                 return -EINVAL;         /* Bigger than a 14-bit value */
 787
 788         sprintf(newkey, fan_speed_fmt[to_option(attr)], to_index(attr));
 789
 790         buffer[0] = (speed >> 6) & 0xff;
 791         buffer[1] = (speed << 2) & 0xff;
 792         ret = applesmc_write_key(newkey, buffer, 2);
 793
 794         if (ret)
 795                 return ret;
 796         else
 797                 return count;
 798 }
 799
 800 static ssize_t applesmc_show_fan_manual(struct device *dev,
 801                         struct device_attribute *attr, char *sysfsbuf)
 802 {
 803         int ret;
 804         u16 manual = 0;
 805         u8 buffer[2];
 806
 807         ret = applesmc_read_key(FANS_MANUAL, buffer, 2);
 808         manual = ((buffer[0] << 8 | buffer[1]) >> to_index(attr)) & 0x01;
 809
 810         if (ret)
 811                 return ret;
 812         else
 813                 return snprintf(sysfsbuf, PAGE_SIZE, "%d\n", manual);
 814 }
 815
 816 static ssize_t applesmc_store_fan_manual(struct device *dev,
 817                                          struct device_attribute *attr,
 818                                          const char *sysfsbuf, size_t count)
 819 {
 820         int ret;
 821         u8 buffer[2];
 822         unsigned long input;
 823         u16 val;
 824
 825         if (strict_strtoul(sysfsbuf, 10, &input) < 0)
 826                 return -EINVAL;
 827
 828         ret = applesmc_read_key(FANS_MANUAL, buffer, 2);
 829         val = (buffer[0] << 8 | buffer[1]);
 830         if (ret)
 831                 goto out;
 832
 833         if (input)
 834                 val = val | (0x01 << to_index(attr));
 835         else
 836                 val = val & ~(0x01 << to_index(attr));
 837
 838         buffer[0] = (val >> 8) & 0xFF;
 839         buffer[1] = val & 0xFF;
 840
 841         ret = applesmc_write_key(FANS_MANUAL, buffer, 2);
 842
 843 out:
 844         if (ret)
 845                 return ret;
 846         else
 847                 return count;
 848 }
 849
 850 static ssize_t applesmc_show_fan_position(struct device *dev,
 851                                 struct device_attribute *attr, char *sysfsbuf)
 852 {
 853         int ret;
 854         char newkey[5];
 855         u8 buffer[17];
 856
 857         sprintf(newkey, FAN_ID_FMT, to_index(attr));
 858
 859         ret = applesmc_read_key(newkey, buffer, 16);
 860         buffer[16] = 0;
 861
 862         if (ret)
 863                 return ret;
 864         else
 865                 return snprintf(sysfsbuf, PAGE_SIZE, "%s\n", buffer+4);
 866 }
 867
 868 static ssize_t applesmc_calibrate_show(struct device *dev,
 869                                 struct device_attribute *attr, char *sysfsbuf)
 870 {
 871         return snprintf(sysfsbuf, PAGE_SIZE, "(%d,%d)\n", rest_x, rest_y);
 872 }
 873
 874 static ssize_t applesmc_calibrate_store(struct device *dev,
 875         struct device_attribute *attr, const char *sysfsbuf, size_t count)
 876 {
 877         applesmc_calibrate();
 878
 879         return count;
 880 }
 881
 882 static void applesmc_backlight_set(struct work_struct *work)
 883 {
 884         applesmc_write_key(BACKLIGHT_KEY, backlight_state, 2);
 885 }
 886 static DECLARE_WORK(backlight_work, &applesmc_backlight_set);
 887
 888 static void applesmc_brightness_set(struct led_classdev *led_cdev,
 889                                                 enum led_brightness value)
 890 {
 891         int ret;
 892
 893         backlight_state[0] = value;
 894         ret = queue_work(applesmc_led_wq, &backlight_work);
 895
 896         if (debug && (!ret))
 897                 printk(KERN_DEBUG "applesmc: work was already on the queue.\n");
 898 }
 899
 900 static ssize_t applesmc_key_count_show(struct device *dev,
 901                                 struct device_attribute *attr, char *sysfsbuf)
 902 {
 903         int ret;
 904         u8 buffer[4];
 905         u32 count;
 906
 907         ret = applesmc_read_key(KEY_COUNT_KEY, buffer, 4);
 908         count = ((u32)buffer[0]<<24) + ((u32)buffer[1]<<16) +
 909                                                 ((u32)buffer[2]<<8) + buffer[3];
 910
 911         if (ret)
 912                 return ret;
 913         else
 914                 return snprintf(sysfsbuf, PAGE_SIZE, "%d\n", count);
 915 }
 916
 917 static ssize_t applesmc_key_at_index_read_show(struct device *dev,
 918                                 struct device_attribute *attr, char *sysfsbuf)
 919 {
 920         const struct applesmc_entry *entry;
 921         int ret;
 922
 923         entry = applesmc_get_entry_by_index(key_at_index);
 924         if (IS_ERR(entry))
 925                 return PTR_ERR(entry);
 926         ret = applesmc_read_entry(entry, sysfsbuf, entry->len);
 927         if (ret)
 928                 return ret;
 929
 930         return entry->len;
 931 }
 932
 933 static ssize_t applesmc_key_at_index_data_length_show(struct device *dev,
 934                                 struct device_attribute *attr, char *sysfsbuf)
 935 {
 936         const struct applesmc_entry *entry;
 937
 938         entry = applesmc_get_entry_by_index(key_at_index);
 939         if (IS_ERR(entry))
 940                 return PTR_ERR(entry);
 941
 942         return snprintf(sysfsbuf, PAGE_SIZE, "%d\n", entry->len);
 943 }
 944
 945 static ssize_t applesmc_key_at_index_type_show(struct device *dev,
 946                                 struct device_attribute *attr, char *sysfsbuf)
 947 {
 948         const struct applesmc_entry *entry;
 949
 950         entry = applesmc_get_entry_by_index(key_at_index);
 951         if (IS_ERR(entry))
 952                 return PTR_ERR(entry);
 953
 954         return snprintf(sysfsbuf, PAGE_SIZE, "%s\n", entry->type);
 955 }
 956
 957 static ssize_t applesmc_key_at_index_name_show(struct device *dev,
 958                                 struct device_attribute *attr, char *sysfsbuf)
 959 {
 960         const struct applesmc_entry *entry;
 961
 962         entry = applesmc_get_entry_by_index(key_at_index);
 963         if (IS_ERR(entry))
 964                 return PTR_ERR(entry);
 965
 966         return snprintf(sysfsbuf, PAGE_SIZE, "%s\n", entry->key);
 967 }
 968
 969 static ssize_t applesmc_key_at_index_show(struct device *dev,
 970                                 struct device_attribute *attr, char *sysfsbuf)
 971 {
 972         return snprintf(sysfsbuf, PAGE_SIZE, "%d\n", key_at_index);
 973 }
 974
 975 static ssize_t applesmc_key_at_index_store(struct device *dev,
 976         struct device_attribute *attr, const char *sysfsbuf, size_t count)
 977 {
 978         unsigned long newkey;
 979
 980         if (strict_strtoul(sysfsbuf, 10, &newkey) < 0
 981             || newkey >= smcreg.key_count)
 982                 return -EINVAL;
 983
 984         key_at_index = newkey;
 985         return count;
 986 }
 987
 988 static struct led_classdev applesmc_backlight = {
 989         .name                   = "smc::kbd_backlight",
 990         .default_trigger        = "nand-disk",
 991         .brightness_set         = applesmc_brightness_set,
 992 };
 993
 994 static struct applesmc_node_group info_group[] = {
 995         { "name", applesmc_name_show },
 996         { "key_count", applesmc_key_count_show },
 997         { "key_at_index", applesmc_key_at_index_show, applesmc_key_at_index_store },
 998         { "key_at_index_name", applesmc_key_at_index_name_show },
 999         { "key_at_index_type", applesmc_key_at_index_type_show },
1000         { "key_at_index_data_length", applesmc_key_at_index_data_length_show },
1001         { "key_at_index_data", applesmc_key_at_index_read_show },
1002         { }
1003 };
1004
1005 static struct applesmc_node_group accelerometer_group[] = {
1006         { "position", applesmc_position_show },
1007         { "calibrate", applesmc_calibrate_show, applesmc_calibrate_store },
1008         { }
1009 };
1010
1011 static struct applesmc_node_group light_sensor_group[] = {
1012         { "light", applesmc_light_show },
1013         { }
1014 };
1015
1016 static struct applesmc_node_group fan_group[] = {
1017         { "fan%d_label", applesmc_show_fan_position },
1018         { "fan%d_input", applesmc_show_fan_speed, NULL, 0 },
1019         { "fan%d_min", applesmc_show_fan_speed, applesmc_store_fan_speed, 1 },
1020         { "fan%d_max", applesmc_show_fan_speed, NULL, 2 },
1021         { "fan%d_safe", applesmc_show_fan_speed, NULL, 3 },
1022         { "fan%d_output", applesmc_show_fan_speed, applesmc_store_fan_speed, 4 },
1023         { "fan%d_manual", applesmc_show_fan_manual, applesmc_store_fan_manual },
1024         { }
1025 };
1026
1027 static struct applesmc_node_group temp_group[] = {
1028         { "temp%d_label", applesmc_show_sensor_label },
1029         { "temp%d_input", applesmc_show_temperature },
1030         { }
1031 };
1032
1033 /* Module stuff */
1034
1035 /*
1036  * applesmc_destroy_nodes - remove files and free associated memory
1037  */
1038 static void applesmc_destroy_nodes(struct applesmc_node_group *groups)
1039 {
1040         struct applesmc_node_group *grp;
1041         struct applesmc_dev_attr *node;
1042
1043         for (grp = groups; grp->nodes; grp++) {
1044                 for (node = grp->nodes; node->sda.dev_attr.attr.name; node++)
1045                         sysfs_remove_file(&pdev->dev.kobj,
1046                                           &node->sda.dev_attr.attr);
1047                 kfree(grp->nodes);
1048                 grp->nodes = NULL;
1049         }
1050 }
1051
1052 /*
1053  * applesmc_create_nodes - create a two-dimensional group of sysfs files
1054  */
1055 static int applesmc_create_nodes(struct applesmc_node_group *groups, int num)
1056 {
1057         struct applesmc_node_group *grp;
1058         struct applesmc_dev_attr *node;
1059         struct attribute *attr;
1060         int ret, i;
1061
1062         for (grp = groups; grp->format; grp++) {
1063                 grp->nodes = kcalloc(num + 1, sizeof(*node), GFP_KERNEL);
1064                 if (!grp->nodes) {
1065                         ret = -ENOMEM;
1066                         goto out;
1067                 }
1068                 for (i = 0; i < num; i++) {
1069                         node = &grp->nodes[i];
1070                         sprintf(node->name, grp->format, i + 1);
1071                         node->sda.index = (grp->option << 16) | (i & 0xffff);
1072                         node->sda.dev_attr.show = grp->show;
1073                         node->sda.dev_attr.store = grp->store;
1074                         attr = &node->sda.dev_attr.attr;
1075                         sysfs_attr_init(attr);
1076                         attr->name = node->name;
1077                         attr->mode = S_IRUGO | (grp->store ? S_IWUSR : 0);
1078                         ret = sysfs_create_file(&pdev->dev.kobj, attr);
1079                         if (ret) {
1080                                 attr->name = NULL;
1081                                 goto out;
1082                         }
1083                 }
1084         }
1085
1086         return 0;
1087 out:
1088         applesmc_destroy_nodes(groups);
1089         return ret;
1090 }
1091
1092 /* Create accelerometer ressources */
1093 static int applesmc_create_accelerometer(void)
1094 {
1095         struct input_dev *idev;
1096         int ret;
1097
1098         if (!smcreg.has_accelerometer)
1099                 return 0;
1100
1101         ret = applesmc_create_nodes(accelerometer_group, 1);
1102         if (ret)
1103                 goto out;
1104
1105         applesmc_idev = input_allocate_polled_device();
1106         if (!applesmc_idev) {
1107                 ret = -ENOMEM;
1108                 goto out_sysfs;
1109         }
1110
1111         applesmc_idev->poll = applesmc_idev_poll;
1112         applesmc_idev->poll_interval = APPLESMC_POLL_INTERVAL;
1113
1114         /* initial calibrate for the input device */
1115         applesmc_calibrate();
1116
1117         /* initialize the input device */
1118         idev = applesmc_idev->input;
1119         idev->name = "applesmc";
1120         idev->id.bustype = BUS_HOST;
1121         idev->dev.parent = &pdev->dev;
1122         idev->evbit[0] = BIT_MASK(EV_ABS);
1123         input_set_abs_params(idev, ABS_X,
1124                         -256, 256, APPLESMC_INPUT_FUZZ, APPLESMC_INPUT_FLAT);
1125         input_set_abs_params(idev, ABS_Y,
1126                         -256, 256, APPLESMC_INPUT_FUZZ, APPLESMC_INPUT_FLAT);
1127
1128         ret = input_register_polled_device(applesmc_idev);
1129         if (ret)
1130                 goto out_idev;
1131
1132         return 0;
1133
1134 out_idev:
1135         input_free_polled_device(applesmc_idev);
1136
1137 out_sysfs:
1138         applesmc_destroy_nodes(accelerometer_group);
1139
1140 out:
1141         pr_warn("driver init failed (ret=%d)!\n", ret);
1142         return ret;
1143 }
1144
1145 /* Release all ressources used by the accelerometer */
1146 static void applesmc_release_accelerometer(void)
1147 {
1148         if (!smcreg.has_accelerometer)
1149                 return;
1150         input_unregister_polled_device(applesmc_idev);
1151         input_free_polled_device(applesmc_idev);
1152         applesmc_destroy_nodes(accelerometer_group);
1153 }
1154
1155 static int applesmc_create_light_sensor(void)
1156 {
1157         if (!smcreg.num_light_sensors)
1158                 return 0;
1159         return applesmc_create_nodes(light_sensor_group, 1);
1160 }
1161
1162 static void applesmc_release_light_sensor(void)
1163 {
1164         if (!smcreg.num_light_sensors)
1165                 return;
1166         applesmc_destroy_nodes(light_sensor_group);
1167 }
1168
1169 static int applesmc_create_key_backlight(void)
1170 {
1171         if (!smcreg.has_key_backlight)
1172                 return 0;
1173         applesmc_led_wq = create_singlethread_workqueue("applesmc-led");
1174         if (!applesmc_led_wq)
1175                 return -ENOMEM;
1176         return led_classdev_register(&pdev->dev, &applesmc_backlight);
1177 }
1178
1179 static void applesmc_release_key_backlight(void)
1180 {
1181         if (!smcreg.has_key_backlight)
1182                 return;
1183         led_classdev_unregister(&applesmc_backlight);
1184         destroy_workqueue(applesmc_led_wq);
1185 }
1186
1187 static int applesmc_dmi_match(const struct dmi_system_id *id)
1188 {
1189         return 1;
1190 }
1191
1192 /* Note that DMI_MATCH(...,"MacBook") will match "MacBookPro1,1".
1193  * So we need to put "Apple MacBook Pro" before "Apple MacBook". */
1194 static __initdata struct dmi_system_id applesmc_whitelist[] = {
1195         { applesmc_dmi_match, "Apple MacBook Air", {
1196           DMI_MATCH(DMI_BOARD_VENDOR, "Apple"),
1197           DMI_MATCH(DMI_PRODUCT_NAME, "MacBookAir") },
1198         },
1199         { applesmc_dmi_match, "Apple MacBook Pro", {
1200           DMI_MATCH(DMI_BOARD_VENDOR, "Apple"),
1201           DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro") },
1202         },
1203         { applesmc_dmi_match, "Apple MacBook", {
1204           DMI_MATCH(DMI_BOARD_VENDOR, "Apple"),
1205           DMI_MATCH(DMI_PRODUCT_NAME, "MacBook") },
1206         },
1207         { applesmc_dmi_match, "Apple Macmini", {
1208           DMI_MATCH(DMI_BOARD_VENDOR, "Apple"),
1209           DMI_MATCH(DMI_PRODUCT_NAME, "Macmini") },
1210         },
1211         { applesmc_dmi_match, "Apple MacPro", {
1212           DMI_MATCH(DMI_BOARD_VENDOR, "Apple"),
1213           DMI_MATCH(DMI_PRODUCT_NAME, "MacPro") },
1214         },
1215         { applesmc_dmi_match, "Apple iMac", {
1216           DMI_MATCH(DMI_BOARD_VENDOR, "Apple"),
1217           DMI_MATCH(DMI_PRODUCT_NAME, "iMac") },
1218         },
1219         { .ident = NULL }
1220 };
1221
1222 static int __init applesmc_init(void)
1223 {
1224         int ret;
1225
1226         if (!dmi_check_system(applesmc_whitelist)) {
1227                 pr_warn("supported laptop not found!\n");
1228                 ret = -ENODEV;
1229                 goto out;
1230         }
1231
1232         if (!request_region(APPLESMC_DATA_PORT, APPLESMC_NR_PORTS,
1233                                                                 "applesmc")) {
1234                 ret = -ENXIO;
1235                 goto out;
1236         }
1237
1238         ret = platform_driver_register(&applesmc_driver);
1239         if (ret)
1240                 goto out_region;
1241
1242         pdev = platform_device_register_simple("applesmc", APPLESMC_DATA_PORT,
1243                                                NULL, 0);
1244         if (IS_ERR(pdev)) {
1245                 ret = PTR_ERR(pdev);
1246                 goto out_driver;
1247         }
1248
1249         /* create register cache */
1250         ret = applesmc_init_smcreg();
1251         if (ret)
1252                 goto out_device;
1253
1254         ret = applesmc_create_nodes(info_group, 1);
1255         if (ret)
1256                 goto out_smcreg;
1257
1258         ret = applesmc_create_nodes(fan_group, smcreg.fan_count);
1259         if (ret)
1260                 goto out_info;
1261
1262         ret = applesmc_create_nodes(temp_group, smcreg.temp_count);
1263         if (ret)
1264                 goto out_fans;
1265
1266         ret = applesmc_create_accelerometer();
1267         if (ret)
1268                 goto out_temperature;
1269
1270         ret = applesmc_create_light_sensor();
1271         if (ret)
1272                 goto out_accelerometer;
1273
1274         ret = applesmc_create_key_backlight();
1275         if (ret)
1276                 goto out_light_sysfs;
1277
1278         hwmon_dev = hwmon_device_register(&pdev->dev);
1279         if (IS_ERR(hwmon_dev)) {
1280                 ret = PTR_ERR(hwmon_dev);
1281                 goto out_light_ledclass;
1282         }
1283
1284         return 0;
1285
1286 out_light_ledclass:
1287         applesmc_release_key_backlight();
1288 out_light_sysfs:
1289         applesmc_release_light_sensor();
1290 out_accelerometer:
1291         applesmc_release_accelerometer();
1292 out_temperature:
1293         applesmc_destroy_nodes(temp_group);
1294 out_fans:
1295         applesmc_destroy_nodes(fan_group);
1296 out_info:
1297         applesmc_destroy_nodes(info_group);
1298 out_smcreg:
1299         applesmc_destroy_smcreg();
1300 out_device:
1301         platform_device_unregister(pdev);
1302 out_driver:
1303         platform_driver_unregister(&applesmc_driver);
1304 out_region:
1305         release_region(APPLESMC_DATA_PORT, APPLESMC_NR_PORTS);
1306 out:
1307         pr_warn("driver init failed (ret=%d)!\n", ret);
1308         return ret;
1309 }
1310
1311 static void __exit applesmc_exit(void)
1312 {
1313         hwmon_device_unregister(hwmon_dev);
1314         applesmc_release_key_backlight();
1315         applesmc_release_light_sensor();
1316         applesmc_release_accelerometer();
1317         applesmc_destroy_nodes(temp_group);
1318         applesmc_destroy_nodes(fan_group);
1319         applesmc_destroy_nodes(info_group);
1320         applesmc_destroy_smcreg();
1321         platform_device_unregister(pdev);
1322         platform_driver_unregister(&applesmc_driver);
1323         release_region(APPLESMC_DATA_PORT, APPLESMC_NR_PORTS);
1324 }
1325
1326 module_init(applesmc_init);
1327 module_exit(applesmc_exit);
1328
1329 MODULE_AUTHOR("Nicolas Boichat");
1330 MODULE_DESCRIPTION("Apple SMC");
1331 MODULE_LICENSE("GPL v2");
1332 MODULE_DEVICE_TABLE(dmi, applesmc_whitelist);