drivers/hwmon/hdaps.c

   1 /*
   2  * drivers/hwmon/hdaps.c - driver for IBM's Hard Drive Active Protection System
   3  *
   4  * Copyright (C) 2005 Robert Love <rml@novell.com>
   5  * Copyright (C) 2005 Jesper Juhl <jesper.juhl@gmail.com>
   6  *
   7  * The HardDisk Active Protection System (hdaps) is present in the IBM ThinkPad
   8  * T41, T42, T43, R51, and X40, at least.  It provides a basic two-axis
   9  * accelerometer and other data, such as the device's temperature.
  10  *
  11  * Based on the document by Mark A. Smith available at
  12  * http://www.almaden.ibm.com/cs/people/marksmith/tpaps.html and a lot of trial
  13  * and error.
  14  *
  15  * This program is free software; you can redistribute it and/or modify it
  16  * under the terms of the GNU General Public License v2 as published by the
  17  * Free Software Foundation.
  18  *
  19  * This program is distributed in the hope that it will be useful, but WITHOUT
  20  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  21  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  22  * more details.
  23  *
  24  * You should have received a copy of the GNU General Public License along with
  25  * this program; if not, write to the Free Software Foundation, Inc.,
  26  * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
  27  */
  28
  29 #include <linux/delay.h>
  30 #include <linux/device.h>
  31 #include <linux/input.h>
  32 #include <linux/kernel.h>
  33 #include <linux/module.h>
  34 #include <linux/timer.h>
  35 #include <linux/dmi.h>
  36 #include <asm/io.h>
  37
  38 #define HDAPS_LOW_PORT          0x1600  /* first port used by hdaps */
  39 #define HDAPS_NR_PORTS          0x30    /* 0x1600 - 0x162f */
  40
  41 #define STATE_FRESH             0x50    /* accelerometer data is fresh */
  42
  43 #define REFRESH_ASYNC           0x00    /* do asynchronous refresh */
  44 #define REFRESH_SYNC            0x01    /* do synchronous refresh */
  45
  46 #define HDAPS_PORT_STATE        0x1611  /* device state */
  47 #define HDAPS_PORT_YPOS         0x1612  /* y-axis position */
  48 #define HDAPS_PORT_XPOS         0x1614  /* x-axis position */
  49 #define HDAPS_PORT_TEMP1        0x1616  /* device temperature, in celcius */
  50 #define HDAPS_PORT_YVAR         0x1617  /* y-axis variance (what is this?) */
  51 #define HDAPS_PORT_XVAR         0x1619  /* x-axis variance (what is this?) */
  52 #define HDAPS_PORT_TEMP2        0x161b  /* device temperature (again?) */
  53 #define HDAPS_PORT_UNKNOWN      0x161c  /* what is this? */
  54 #define HDAPS_PORT_KMACT        0x161d  /* keyboard or mouse activity */
  55
  56 #define HDAPS_READ_MASK         0xff    /* some reads have the low 8 bits set */
  57
  58 #define KEYBD_MASK              0x20    /* set if keyboard activity */
  59 #define MOUSE_MASK              0x40    /* set if mouse activity */
  60 #define KEYBD_ISSET(n)          (!! (n & KEYBD_MASK))   /* keyboard used? */
  61 #define MOUSE_ISSET(n)          (!! (n & MOUSE_MASK))   /* mouse used? */
  62
  63 #define INIT_TIMEOUT_MSECS      4000    /* wait up to 4s for device init ... */
  64 #define INIT_WAIT_MSECS         200     /* ... in 200ms increments */
  65
  66 static struct platform_device *pdev;
  67 static struct input_dev hdaps_idev;
  68 static struct timer_list hdaps_timer;
  69 static unsigned int hdaps_mousedev_threshold = 4;
  70 static unsigned long hdaps_poll_ms = 50;
  71 static unsigned int hdaps_mousedev;
  72 static unsigned int hdaps_invert;
  73 static u8 km_activity;
  74 static int rest_x;
  75 static int rest_y;
  76
  77 static DECLARE_MUTEX(hdaps_sem);
  78
  79 /*
  80  * __get_latch - Get the value from a given port.  Callers must hold hdaps_sem.
  81  */
  82 static inline u8 __get_latch(u16 port)
  83 {
  84         return inb(port) & HDAPS_READ_MASK;
  85 }
  86
  87 /*
  88  * __check_latch - Check a port latch for a given value.  Callers must hold
  89  * hdaps_sem.  Returns zero if the port contains the given value.
  90  */
  91 static inline unsigned int __check_latch(u16 port, u8 val)
  92 {
  93         if (__get_latch(port) == val)
  94                 return 0;
  95         return -EINVAL;
  96 }
  97
  98 /*
  99  * __wait_latch - Wait up to 100us for a port latch to get a certain value,
 100  * returning zero if the value is obtained.  Callers must hold hdaps_sem.
 101  */
 102 static unsigned int __wait_latch(u16 port, u8 val)
 103 {
 104         unsigned int i;
 105
 106         for (i = 0; i < 20; i++) {
 107                 if (!__check_latch(port, val))
 108                         return 0;
 109                 udelay(5);
 110         }
 111
 112         return -EINVAL;
 113 }
 114
 115 /*
 116  * __device_refresh - Request a refresh from the accelerometer.
 117  *
 118  * If sync is REFRESH_SYNC, we perform a synchronous refresh and will wait.
 119  * Returns zero if successful and nonzero on error.
 120  *
 121  * If sync is REFRESH_ASYNC, we merely kick off a new refresh if the device is
 122  * not up-to-date.  Always returns zero.
 123  *
 124  * Callers must hold hdaps_sem.
 125  */
 126 static int __device_refresh(unsigned int sync)
 127 {
 128         u8 state;
 129
 130         udelay(100);
 131
 132         state = inb(0x1604);
 133         if (state == STATE_FRESH)
 134                 return 0;
 135
 136         outb(0x11, 0x1610);
 137         outb(0x01, 0x161f);
 138         if (sync == REFRESH_ASYNC)
 139                 return 0;
 140
 141         return __wait_latch(0x1604, STATE_FRESH);
 142 }
 143
 144 /*
 145  * __device_complete - Indicate to the accelerometer that we are done reading
 146  * data, and then initiate an async refresh.  Callers must hold hdaps_sem.
 147  */
 148 static inline void __device_complete(void)
 149 {
 150         inb(0x161f);
 151         inb(0x1604);
 152         __device_refresh(REFRESH_ASYNC);
 153 }
 154
 155 static int __hdaps_readb_one(unsigned int port, u8 *val)
 156 {
 157         /* do a sync refresh -- we need to be sure that we read fresh data */
 158         if (__device_refresh(REFRESH_SYNC))
 159                 return -EIO;
 160
 161         *val = inb(port);
 162         __device_complete();
 163
 164         return 0;
 165 }
 166
 167 /*
 168  * hdaps_readb_one - reads a byte from a single I/O port, placing the value in
 169  * the given pointer.  Returns zero on success or a negative error on failure.
 170  * Can sleep.
 171  */
 172 static int hdaps_readb_one(unsigned int port, u8 *val)
 173 {
 174         int ret;
 175
 176         down(&hdaps_sem);
 177         ret = __hdaps_readb_one(port, val);
 178         up(&hdaps_sem);
 179
 180         return ret;
 181 }
 182
 183 static int __hdaps_read_pair(unsigned int port1, unsigned int port2,
 184                              int *x, int *y)
 185 {
 186         /* do a sync refresh -- we need to be sure that we read fresh data */
 187         if (__device_refresh(REFRESH_SYNC))
 188                 return -EIO;
 189
 190         *y = inw(port2);
 191         *x = inw(port1);
 192         km_activity = inb(HDAPS_PORT_KMACT);
 193         __device_complete();
 194
 195         /* if hdaps_invert is set, negate the two values */
 196         if (hdaps_invert) {
 197                 *x = -*x;
 198                 *y = -*y;
 199         }
 200
 201         return 0;
 202 }
 203
 204 /*
 205  * hdaps_read_pair - reads the values from a pair of ports, placing the values
 206  * in the given pointers.  Returns zero on success.  Can sleep.
 207  */
 208 static int hdaps_read_pair(unsigned int port1, unsigned int port2,
 209                            int *val1, int *val2)
 210 {
 211         int ret;
 212
 213         down(&hdaps_sem);
 214         ret = __hdaps_read_pair(port1, port2, val1, val2);
 215         up(&hdaps_sem);
 216
 217         return ret;
 218 }
 219
 220 /* initialize the accelerometer */
 221 static int hdaps_device_init(void)
 222 {
 223         unsigned int total_msecs = INIT_TIMEOUT_MSECS;
 224         int ret = -ENXIO;
 225
 226         down(&hdaps_sem);
 227
 228         outb(0x13, 0x1610);
 229         outb(0x01, 0x161f);
 230         if (__wait_latch(0x161f, 0x00))
 231                 goto out;
 232
 233         /*
 234          * The 0x03 value appears to only work on some thinkpads, such as the
 235          * T42p.  Others return 0x01.
 236          *
 237          * The 0x02 value occurs when the chip has been previously initialized.
 238          */
 239         if (__check_latch(0x1611, 0x03) &&
 240                      __check_latch(0x1611, 0x02) &&
 241                      __check_latch(0x1611, 0x01))
 242                 goto out;
 243
 244         printk(KERN_DEBUG "hdaps: initial latch check good (0x%02x).\n",
 245                __get_latch(0x1611));
 246
 247         outb(0x17, 0x1610);
 248         outb(0x81, 0x1611);
 249         outb(0x01, 0x161f);
 250         if (__wait_latch(0x161f, 0x00))
 251                 goto out;
 252         if (__wait_latch(0x1611, 0x00))
 253                 goto out;
 254         if (__wait_latch(0x1612, 0x60))
 255                 goto out;
 256         if (__wait_latch(0x1613, 0x00))
 257                 goto out;
 258         outb(0x14, 0x1610);
 259         outb(0x01, 0x1611);
 260         outb(0x01, 0x161f);
 261         if (__wait_latch(0x161f, 0x00))
 262                 goto out;
 263         outb(0x10, 0x1610);
 264         outb(0xc8, 0x1611);
 265         outb(0x00, 0x1612);
 266         outb(0x02, 0x1613);
 267         outb(0x01, 0x161f);
 268         if (__wait_latch(0x161f, 0x00))
 269                 goto out;
 270         if (__device_refresh(REFRESH_SYNC))
 271                 goto out;
 272         if (__wait_latch(0x1611, 0x00))
 273                 goto out;
 274
 275         /* we have done our dance, now let's wait for the applause */
 276         while (total_msecs > 0) {
 277                 u8 ignored;
 278
 279                 /* a read of the device helps push it into action */
 280                 __hdaps_readb_one(HDAPS_PORT_UNKNOWN, &ignored);
 281                 if (!__wait_latch(0x1611, 0x02)) {
 282                         ret = 0;
 283                         break;
 284                 }
 285
 286                 msleep(INIT_WAIT_MSECS);
 287                 total_msecs -= INIT_WAIT_MSECS;
 288         }
 289
 290 out:
 291         up(&hdaps_sem);
 292         return ret;
 293 }
 294
 295
 296 /* Input class stuff */
 297
 298 /*
 299  * hdaps_calibrate - Zero out our "resting" values. Callers must hold hdaps_sem.
 300  */
 301 static void hdaps_calibrate(void)
 302 {
 303         int x, y;
 304
 305         if (__hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &x, &y))
 306                 return;
 307
 308         rest_x = x;
 309         rest_y = y;
 310 }
 311
 312 static void hdaps_mousedev_poll(unsigned long unused)
 313 {
 314         int x, y;
 315
 316         /* Cannot sleep.  Try nonblockingly.  If we fail, try again later. */
 317         if (down_trylock(&hdaps_sem)) {
 318                 mod_timer(&hdaps_timer,jiffies+msecs_to_jiffies(hdaps_poll_ms));
 319                 return;
 320         }
 321
 322         if (__hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &x, &y))
 323                 goto out;
 324
 325         x -= rest_x;
 326         y -= rest_y;
 327         if (abs(x) > hdaps_mousedev_threshold)
 328                 input_report_rel(&hdaps_idev, REL_X, x);
 329         if (abs(y) > hdaps_mousedev_threshold)
 330                 input_report_rel(&hdaps_idev, REL_Y, y);
 331         input_sync(&hdaps_idev);
 332
 333         mod_timer(&hdaps_timer, jiffies + msecs_to_jiffies(hdaps_poll_ms));
 334
 335 out:
 336         up(&hdaps_sem);
 337 }
 338
 339 /*
 340  * hdaps_mousedev_enable - enable the input class device.  Can sleep.
 341  */
 342 static void hdaps_mousedev_enable(void)
 343 {
 344         down(&hdaps_sem);
 345
 346         /* calibrate the device before enabling */
 347         hdaps_calibrate();
 348
 349         /* initialize the input class */
 350         init_input_dev(&hdaps_idev);
 351         hdaps_idev.dev = &pdev->dev;
 352         hdaps_idev.evbit[0] = BIT(EV_KEY) | BIT(EV_REL);
 353         hdaps_idev.relbit[0] = BIT(REL_X) | BIT(REL_Y);
 354         hdaps_idev.keybit[LONG(BTN_LEFT)] = BIT(BTN_LEFT);
 355         input_register_device(&hdaps_idev);
 356
 357         /* start up our timer */
 358         init_timer(&hdaps_timer);
 359         hdaps_timer.function = hdaps_mousedev_poll;
 360         hdaps_timer.expires = jiffies + msecs_to_jiffies(hdaps_poll_ms);
 361         add_timer(&hdaps_timer);
 362
 363         hdaps_mousedev = 1;
 364
 365         up(&hdaps_sem);
 366
 367         printk(KERN_INFO "hdaps: input device enabled.\n");
 368 }
 369
 370 /*
 371  * hdaps_mousedev_disable - disable the input class device.  Caller must hold
 372  * hdaps_sem.
 373  */
 374 static void hdaps_mousedev_disable(void)
 375 {
 376         down(&hdaps_sem);
 377         if (hdaps_mousedev) {
 378                 hdaps_mousedev = 0;
 379                 del_timer_sync(&hdaps_timer);
 380                 input_unregister_device(&hdaps_idev);
 381         }
 382         up(&hdaps_sem);
 383 }
 384
 385
 386 /* Device model stuff */
 387
 388 static int hdaps_probe(struct device *dev)
 389 {
 390         int ret;
 391
 392         ret = hdaps_device_init();
 393         if (ret)
 394                 return ret;
 395
 396         printk(KERN_INFO "hdaps: device successfully initialized.\n");
 397         return 0;
 398 }
 399
 400 static int hdaps_resume(struct device *dev, u32 level)
 401 {
 402         if (level == RESUME_ENABLE)
 403                 return hdaps_device_init();
 404         return 0;
 405 }
 406
 407 static struct device_driver hdaps_driver = {
 408         .name = "hdaps",
 409         .bus = &platform_bus_type,
 410         .owner = THIS_MODULE,
 411         .probe = hdaps_probe,
 412         .resume = hdaps_resume
 413 };
 414
 415
 416 /* Sysfs Files */
 417
 418 static ssize_t hdaps_position_show(struct device *dev,
 419                                    struct device_attribute *attr, char *buf)
 420 {
 421         int ret, x, y;
 422
 423         ret = hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &x, &y);
 424         if (ret)
 425                 return ret;
 426
 427         return sprintf(buf, "(%d,%d)\n", x, y);
 428 }
 429
 430 static ssize_t hdaps_variance_show(struct device *dev,
 431                                    struct device_attribute *attr, char *buf)
 432 {
 433         int ret, x, y;
 434
 435         ret = hdaps_read_pair(HDAPS_PORT_XVAR, HDAPS_PORT_YVAR, &x, &y);
 436         if (ret)
 437                 return ret;
 438
 439         return sprintf(buf, "(%d,%d)\n", x, y);
 440 }
 441
 442 static ssize_t hdaps_temp1_show(struct device *dev,
 443                                 struct device_attribute *attr, char *buf)
 444 {
 445         u8 temp;
 446         int ret;
 447
 448         ret = hdaps_readb_one(HDAPS_PORT_TEMP1, &temp);
 449         if (ret < 0)
 450                 return ret;
 451
 452         return sprintf(buf, "%u\n", temp);
 453 }
 454
 455 static ssize_t hdaps_temp2_show(struct device *dev,
 456                                 struct device_attribute *attr, char *buf)
 457 {
 458         u8 temp;
 459         int ret;
 460
 461         ret = hdaps_readb_one(HDAPS_PORT_TEMP2, &temp);
 462         if (ret < 0)
 463                 return ret;
 464
 465         return sprintf(buf, "%u\n", temp);
 466 }
 467
 468 static ssize_t hdaps_keyboard_activity_show(struct device *dev,
 469                                             struct device_attribute *attr,
 470                                             char *buf)
 471 {
 472         return sprintf(buf, "%u\n", KEYBD_ISSET(km_activity));
 473 }
 474
 475 static ssize_t hdaps_mouse_activity_show(struct device *dev,
 476                                          struct device_attribute *attr,
 477                                          char *buf)
 478 {
 479         return sprintf(buf, "%u\n", MOUSE_ISSET(km_activity));
 480 }
 481
 482 static ssize_t hdaps_calibrate_show(struct device *dev,
 483                                     struct device_attribute *attr, char *buf)
 484 {
 485         return sprintf(buf, "(%d,%d)\n", rest_x, rest_y);
 486 }
 487
 488 static ssize_t hdaps_calibrate_store(struct device *dev,
 489                                      struct device_attribute *attr,
 490                                      const char *buf, size_t count)
 491 {
 492         down(&hdaps_sem);
 493         hdaps_calibrate();
 494         up(&hdaps_sem);
 495
 496         return count;
 497 }
 498
 499 static ssize_t hdaps_invert_show(struct device *dev,
 500                                  struct device_attribute *attr, char *buf)
 501 {
 502         return sprintf(buf, "%u\n", hdaps_invert);
 503 }
 504
 505 static ssize_t hdaps_invert_store(struct device *dev,
 506                                   struct device_attribute *attr,
 507                                   const char *buf, size_t count)
 508 {
 509         int invert;
 510
 511         if (sscanf(buf, "%d", &invert) != 1 || (invert != 1 && invert != 0))
 512                 return -EINVAL;
 513
 514         hdaps_invert = invert;
 515         hdaps_calibrate();
 516
 517         return count;
 518 }
 519
 520 static ssize_t hdaps_mousedev_show(struct device *dev,
 521                                    struct device_attribute *attr, char *buf)
 522 {
 523         return sprintf(buf, "%d\n", hdaps_mousedev);
 524 }
 525
 526 static ssize_t hdaps_mousedev_store(struct device *dev,
 527                                     struct device_attribute *attr,
 528                                     const char *buf, size_t count)
 529 {
 530         int enable;
 531
 532         if (sscanf(buf, "%d", &enable) != 1)
 533                 return -EINVAL;
 534
 535         if (enable == 1)
 536                 hdaps_mousedev_enable();
 537         else if (enable == 0)
 538                 hdaps_mousedev_disable();
 539         else
 540                 return -EINVAL;
 541
 542         return count;
 543 }
 544
 545 static ssize_t hdaps_poll_show(struct device *dev,
 546                                struct device_attribute *attr, char *buf)
 547 {
 548         return sprintf(buf, "%lu\n", hdaps_poll_ms);
 549 }
 550
 551 static ssize_t hdaps_poll_store(struct device *dev,
 552                                 struct device_attribute *attr,
 553                                 const char *buf, size_t count)
 554 {
 555         unsigned int poll;
 556
 557         if (sscanf(buf, "%u", &poll) != 1 || poll == 0)
 558                 return -EINVAL;
 559         hdaps_poll_ms = poll;
 560
 561         return count;
 562 }
 563
 564 static ssize_t hdaps_threshold_show(struct device *dev,
 565                                     struct device_attribute *attr, char *buf)
 566 {
 567         return sprintf(buf, "%u\n", hdaps_mousedev_threshold);
 568 }
 569
 570 static ssize_t hdaps_threshold_store(struct device *dev,
 571                                      struct device_attribute *attr,
 572                                      const char *buf, size_t count)
 573 {
 574         unsigned int threshold;
 575
 576         if (sscanf(buf, "%u", &threshold) != 1 || threshold == 0)
 577                 return -EINVAL;
 578         hdaps_mousedev_threshold = threshold;
 579
 580         return count;
 581 }
 582
 583 static DEVICE_ATTR(position, 0444, hdaps_position_show, NULL);
 584 static DEVICE_ATTR(variance, 0444, hdaps_variance_show, NULL);
 585 static DEVICE_ATTR(temp1, 0444, hdaps_temp1_show, NULL);
 586 static DEVICE_ATTR(temp2, 0444, hdaps_temp2_show, NULL);
 587 static DEVICE_ATTR(keyboard_activity, 0444, hdaps_keyboard_activity_show, NULL);
 588 static DEVICE_ATTR(mouse_activity, 0444, hdaps_mouse_activity_show, NULL);
 589 static DEVICE_ATTR(calibrate, 0644, hdaps_calibrate_show,hdaps_calibrate_store);
 590 static DEVICE_ATTR(invert, 0644, hdaps_invert_show, hdaps_invert_store);
 591 static DEVICE_ATTR(mousedev, 0644, hdaps_mousedev_show, hdaps_mousedev_store);
 592 static DEVICE_ATTR(mousedev_poll_ms, 0644, hdaps_poll_show, hdaps_poll_store);
 593 static DEVICE_ATTR(mousedev_threshold, 0644, hdaps_threshold_show,
 594                    hdaps_threshold_store);
 595
 596 static struct attribute *hdaps_attributes[] = {
 597         &dev_attr_position.attr,
 598         &dev_attr_variance.attr,
 599         &dev_attr_temp1.attr,
 600         &dev_attr_temp2.attr,
 601         &dev_attr_keyboard_activity.attr,
 602         &dev_attr_mouse_activity.attr,
 603         &dev_attr_calibrate.attr,
 604         &dev_attr_mousedev.attr,
 605         &dev_attr_mousedev_threshold.attr,
 606         &dev_attr_mousedev_poll_ms.attr,
 607         &dev_attr_invert.attr,
 608         NULL,
 609 };
 610
 611 static struct attribute_group hdaps_attribute_group = {
 612         .attrs = hdaps_attributes,
 613 };
 614
 615
 616 /* Module stuff */
 617
 618 /*
 619  * XXX: We should be able to return nonzero and halt the detection process.
 620  * But there is a bug in dmi_check_system() where a nonzero return from the
 621  * first match will result in a return of failure from dmi_check_system().
 622  * I fixed this; the patch is in 2.6-mm.  Once in Linus's tree we can make
 623  * hdaps_dmi_match_invert() return hdaps_dmi_match(), which in turn returns 1.
 624  */
 625 static int hdaps_dmi_match(struct dmi_system_id *id)
 626 {
 627         printk(KERN_INFO "hdaps: %s detected.\n", id->ident);
 628         return 0;
 629 }
 630
 631 static int hdaps_dmi_match_invert(struct dmi_system_id *id)
 632 {
 633         hdaps_invert = 1;
 634         printk(KERN_INFO "hdaps: inverting axis readings.\n");
 635         return 0;
 636 }
 637
 638 #define HDAPS_DMI_MATCH_NORMAL(model)   {               \
 639         .ident = "IBM " model,                          \
 640         .callback = hdaps_dmi_match,                    \
 641         .matches = {                                    \
 642                 DMI_MATCH(DMI_BOARD_VENDOR, "IBM"),     \
 643                 DMI_MATCH(DMI_PRODUCT_VERSION, model)   \
 644         }                                               \
 645 }
 646
 647 #define HDAPS_DMI_MATCH_INVERT(model)   {               \
 648         .ident = "IBM " model,                          \
 649         .callback = hdaps_dmi_match_invert,             \
 650         .matches = {                                    \
 651                 DMI_MATCH(DMI_BOARD_VENDOR, "IBM"),     \
 652                 DMI_MATCH(DMI_PRODUCT_VERSION, model)   \
 653         }                                               \
 654 }
 655
 656 static int __init hdaps_init(void)
 657 {
 658         int ret;
 659
 660         /* Note that DMI_MATCH(...,"ThinkPad T42") will match "ThinkPad T42p" */
 661         struct dmi_system_id hdaps_whitelist[] = {
 662                 HDAPS_DMI_MATCH_INVERT("ThinkPad R50p"),
 663                 HDAPS_DMI_MATCH_NORMAL("ThinkPad R50"),
 664                 HDAPS_DMI_MATCH_NORMAL("ThinkPad R51"),
 665                 HDAPS_DMI_MATCH_INVERT("ThinkPad T41p"),
 666                 HDAPS_DMI_MATCH_NORMAL("ThinkPad T41"),
 667                 HDAPS_DMI_MATCH_INVERT("ThinkPad T42p"),
 668                 HDAPS_DMI_MATCH_NORMAL("ThinkPad T42"),
 669                 HDAPS_DMI_MATCH_NORMAL("ThinkPad T43"),
 670                 HDAPS_DMI_MATCH_NORMAL("ThinkPad X40"),
 671                 { .ident = NULL }
 672         };
 673
 674         if (!dmi_check_system(hdaps_whitelist)) {
 675                 printk(KERN_WARNING "hdaps: supported laptop not found!\n");
 676                 ret = -ENXIO;
 677                 goto out;
 678         }
 679
 680         if (!request_region(HDAPS_LOW_PORT, HDAPS_NR_PORTS, "hdaps")) {
 681                 ret = -ENXIO;
 682                 goto out;
 683         }
 684
 685         ret = driver_register(&hdaps_driver);
 686         if (ret)
 687                 goto out_region;
 688
 689         pdev = platform_device_register_simple("hdaps", -1, NULL, 0);
 690         if (IS_ERR(pdev)) {
 691                 ret = PTR_ERR(pdev);
 692                 goto out_driver;
 693         }
 694
 695         ret = sysfs_create_group(&pdev->dev.kobj, &hdaps_attribute_group);
 696         if (ret)
 697                 goto out_device;
 698
 699         if (hdaps_mousedev)
 700                 hdaps_mousedev_enable();
 701
 702         printk(KERN_INFO "hdaps: driver successfully loaded.\n");
 703         return 0;
 704
 705 out_device:
 706         platform_device_unregister(pdev);
 707 out_driver:
 708         driver_unregister(&hdaps_driver);
 709 out_region:
 710         release_region(HDAPS_LOW_PORT, HDAPS_NR_PORTS);
 711 out:
 712         printk(KERN_WARNING "hdaps: driver init failed (ret=%d)!\n", ret);
 713         return ret;
 714 }
 715
 716 static void __exit hdaps_exit(void)
 717 {
 718         hdaps_mousedev_disable();
 719
 720         sysfs_remove_group(&pdev->dev.kobj, &hdaps_attribute_group);
 721         platform_device_unregister(pdev);
 722         driver_unregister(&hdaps_driver);
 723         release_region(HDAPS_LOW_PORT, HDAPS_NR_PORTS);
 724
 725         printk(KERN_INFO "hdaps: driver unloaded.\n");
 726 }
 727
 728 module_init(hdaps_init);
 729 module_exit(hdaps_exit);
 730
 731 module_param_named(mousedev, hdaps_mousedev, bool, 0);
 732 MODULE_PARM_DESC(mousedev, "enable the input class device");
 733
 734 module_param_named(invert, hdaps_invert, bool, 0);
 735 MODULE_PARM_DESC(invert, "invert data along each axis");
 736
 737 MODULE_AUTHOR("Robert Love");
 738 MODULE_DESCRIPTION("IBM Hard Drive Active Protection System (HDAPS) driver");
 739 MODULE_LICENSE("GPL v2");