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 IBM ThinkPads
   8  * starting with the R40, T41, and X40.  It provides a basic two-axis
   9  * accelerometer and other data, such as the device's temperature.
  10  *
  11  * This driver is 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/platform_device.h>
  31 #include <linux/input-polldev.h>
  32 #include <linux/kernel.h>
  33 #include <linux/mutex.h>
  34 #include <linux/module.h>
  35 #include <linux/timer.h>
  36 #include <linux/dmi.h>
  37 #include <linux/jiffies.h>
  38
  39 #include <asm/io.h>
  40
  41 #define HDAPS_LOW_PORT          0x1600  /* first port used by hdaps */
  42 #define HDAPS_NR_PORTS          0x30    /* number of ports: 0x1600 - 0x162f */
  43
  44 #define HDAPS_PORT_STATE        0x1611  /* device state */
  45 #define HDAPS_PORT_YPOS         0x1612  /* y-axis position */
  46 #define HDAPS_PORT_XPOS         0x1614  /* x-axis position */
  47 #define HDAPS_PORT_TEMP1        0x1616  /* device temperature, in Celsius */
  48 #define HDAPS_PORT_YVAR         0x1617  /* y-axis variance (what is this?) */
  49 #define HDAPS_PORT_XVAR         0x1619  /* x-axis variance (what is this?) */
  50 #define HDAPS_PORT_TEMP2        0x161b  /* device temperature (again?) */
  51 #define HDAPS_PORT_UNKNOWN      0x161c  /* what is this? */
  52 #define HDAPS_PORT_KMACT        0x161d  /* keyboard or mouse activity */
  53
  54 #define STATE_FRESH             0x50    /* accelerometer data is fresh */
  55
  56 #define KEYBD_MASK              0x20    /* set if keyboard activity */
  57 #define MOUSE_MASK              0x40    /* set if mouse activity */
  58 #define KEYBD_ISSET(n)          (!! (n & KEYBD_MASK))   /* keyboard used? */
  59 #define MOUSE_ISSET(n)          (!! (n & MOUSE_MASK))   /* mouse used? */
  60
  61 #define INIT_TIMEOUT_MSECS      4000    /* wait up to 4s for device init ... */
  62 #define INIT_WAIT_MSECS         200     /* ... in 200ms increments */
  63
  64 #define HDAPS_POLL_INTERVAL     50      /* poll for input every 1/20s (50 ms)*/
  65 #define HDAPS_INPUT_FUZZ        4       /* input event threshold */
  66 #define HDAPS_INPUT_FLAT        4
  67
  68 static struct platform_device *pdev;
  69 static struct input_polled_dev *hdaps_idev;
  70 static unsigned int hdaps_invert;
  71 static u8 km_activity;
  72 static int rest_x;
  73 static int rest_y;
  74
  75 static DEFINE_MUTEX(hdaps_mtx);
  76
  77 /*
  78  * __get_latch - Get the value from a given port.  Callers must hold hdaps_mtx.
  79  */
  80 static inline u8 __get_latch(u16 port)
  81 {
  82         return inb(port) & 0xff;
  83 }
  84
  85 /*
  86  * __check_latch - Check a port latch for a given value.  Returns zero if the
  87  * port contains the given value.  Callers must hold hdaps_mtx.
  88  */
  89 static inline int __check_latch(u16 port, u8 val)
  90 {
  91         if (__get_latch(port) == val)
  92                 return 0;
  93         return -EINVAL;
  94 }
  95
  96 /*
  97  * __wait_latch - Wait up to 100us for a port latch to get a certain value,
  98  * returning zero if the value is obtained.  Callers must hold hdaps_mtx.
  99  */
 100 static int __wait_latch(u16 port, u8 val)
 101 {
 102         unsigned int i;
 103
 104         for (i = 0; i < 20; i++) {
 105                 if (!__check_latch(port, val))
 106                         return 0;
 107                 udelay(5);
 108         }
 109
 110         return -EIO;
 111 }
 112
 113 /*
 114  * __device_refresh - request a refresh from the accelerometer.  Does not wait
 115  * for refresh to complete.  Callers must hold hdaps_mtx.
 116  */
 117 static void __device_refresh(void)
 118 {
 119         udelay(200);
 120         if (inb(0x1604) != STATE_FRESH) {
 121                 outb(0x11, 0x1610);
 122                 outb(0x01, 0x161f);
 123         }
 124 }
 125
 126 /*
 127  * __device_refresh_sync - request a synchronous refresh from the
 128  * accelerometer.  We wait for the refresh to complete.  Returns zero if
 129  * successful and nonzero on error.  Callers must hold hdaps_mtx.
 130  */
 131 static int __device_refresh_sync(void)
 132 {
 133         __device_refresh();
 134         return __wait_latch(0x1604, STATE_FRESH);
 135 }
 136
 137 /*
 138  * __device_complete - indicate to the accelerometer that we are done reading
 139  * data, and then initiate an async refresh.  Callers must hold hdaps_mtx.
 140  */
 141 static inline void __device_complete(void)
 142 {
 143         inb(0x161f);
 144         inb(0x1604);
 145         __device_refresh();
 146 }
 147
 148 /*
 149  * hdaps_readb_one - reads a byte from a single I/O port, placing the value in
 150  * the given pointer.  Returns zero on success or a negative error on failure.
 151  * Can sleep.
 152  */
 153 static int hdaps_readb_one(unsigned int port, u8 *val)
 154 {
 155         int ret;
 156
 157         mutex_lock(&hdaps_mtx);
 158
 159         /* do a sync refresh -- we need to be sure that we read fresh data */
 160         ret = __device_refresh_sync();
 161         if (ret)
 162                 goto out;
 163
 164         *val = inb(port);
 165         __device_complete();
 166
 167 out:
 168         mutex_unlock(&hdaps_mtx);
 169         return ret;
 170 }
 171
 172 /* __hdaps_read_pair - internal lockless helper for hdaps_read_pair(). */
 173 static int __hdaps_read_pair(unsigned int port1, unsigned int port2,
 174                              int *x, int *y)
 175 {
 176         /* do a sync refresh -- we need to be sure that we read fresh data */
 177         if (__device_refresh_sync())
 178                 return -EIO;
 179
 180         *y = inw(port2);
 181         *x = inw(port1);
 182         km_activity = inb(HDAPS_PORT_KMACT);
 183         __device_complete();
 184
 185         /* if hdaps_invert is set, negate the two values */
 186         if (hdaps_invert) {
 187                 *x = -*x;
 188                 *y = -*y;
 189         }
 190
 191         return 0;
 192 }
 193
 194 /*
 195  * hdaps_read_pair - reads the values from a pair of ports, placing the values
 196  * in the given pointers.  Returns zero on success.  Can sleep.
 197  */
 198 static int hdaps_read_pair(unsigned int port1, unsigned int port2,
 199                            int *val1, int *val2)
 200 {
 201         int ret;
 202
 203         mutex_lock(&hdaps_mtx);
 204         ret = __hdaps_read_pair(port1, port2, val1, val2);
 205         mutex_unlock(&hdaps_mtx);
 206
 207         return ret;
 208 }
 209
 210 /*
 211  * hdaps_device_init - initialize the accelerometer.  Returns zero on success
 212  * and negative error code on failure.  Can sleep.
 213  */
 214 static int hdaps_device_init(void)
 215 {
 216         int total, ret = -ENXIO;
 217
 218         mutex_lock(&hdaps_mtx);
 219
 220         outb(0x13, 0x1610);
 221         outb(0x01, 0x161f);
 222         if (__wait_latch(0x161f, 0x00))
 223                 goto out;
 224
 225         /*
 226          * Most ThinkPads return 0x01.
 227          *
 228          * Others--namely the R50p, T41p, and T42p--return 0x03.  These laptops
 229          * have "inverted" axises.
 230          *
 231          * The 0x02 value occurs when the chip has been previously initialized.
 232          */
 233         if (__check_latch(0x1611, 0x03) &&
 234                      __check_latch(0x1611, 0x02) &&
 235                      __check_latch(0x1611, 0x01))
 236                 goto out;
 237
 238         printk(KERN_DEBUG "hdaps: initial latch check good (0x%02x).\n",
 239                __get_latch(0x1611));
 240
 241         outb(0x17, 0x1610);
 242         outb(0x81, 0x1611);
 243         outb(0x01, 0x161f);
 244         if (__wait_latch(0x161f, 0x00))
 245                 goto out;
 246         if (__wait_latch(0x1611, 0x00))
 247                 goto out;
 248         if (__wait_latch(0x1612, 0x60))
 249                 goto out;
 250         if (__wait_latch(0x1613, 0x00))
 251                 goto out;
 252         outb(0x14, 0x1610);
 253         outb(0x01, 0x1611);
 254         outb(0x01, 0x161f);
 255         if (__wait_latch(0x161f, 0x00))
 256                 goto out;
 257         outb(0x10, 0x1610);
 258         outb(0xc8, 0x1611);
 259         outb(0x00, 0x1612);
 260         outb(0x02, 0x1613);
 261         outb(0x01, 0x161f);
 262         if (__wait_latch(0x161f, 0x00))
 263                 goto out;
 264         if (__device_refresh_sync())
 265                 goto out;
 266         if (__wait_latch(0x1611, 0x00))
 267                 goto out;
 268
 269         /* we have done our dance, now let's wait for the applause */
 270         for (total = INIT_TIMEOUT_MSECS; total > 0; total -= INIT_WAIT_MSECS) {
 271                 int x, y;
 272
 273                 /* a read of the device helps push it into action */
 274                 __hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &x, &y);
 275                 if (!__wait_latch(0x1611, 0x02)) {
 276                         ret = 0;
 277                         break;
 278                 }
 279
 280                 msleep(INIT_WAIT_MSECS);
 281         }
 282
 283 out:
 284         mutex_unlock(&hdaps_mtx);
 285         return ret;
 286 }
 287
 288
 289 /* Device model stuff */
 290
 291 static int hdaps_probe(struct platform_device *dev)
 292 {
 293         int ret;
 294
 295         ret = hdaps_device_init();
 296         if (ret)
 297                 return ret;
 298
 299         printk(KERN_INFO "hdaps: device successfully initialized.\n");
 300         return 0;
 301 }
 302
 303 static int hdaps_resume(struct platform_device *dev)
 304 {
 305         return hdaps_device_init();
 306 }
 307
 308 static struct platform_driver hdaps_driver = {
 309         .probe = hdaps_probe,
 310         .resume = hdaps_resume,
 311         .driver = {
 312                 .name = "hdaps",
 313                 .owner = THIS_MODULE,
 314         },
 315 };
 316
 317 /*
 318  * hdaps_calibrate - Set our "resting" values.  Callers must hold hdaps_mtx.
 319  */
 320 static void hdaps_calibrate(void)
 321 {
 322         __hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &rest_x, &rest_y);
 323 }
 324
 325 static void hdaps_mousedev_poll(struct input_polled_dev *dev)
 326 {
 327         struct input_dev *input_dev = dev->input;
 328         int x, y;
 329
 330         mutex_lock(&hdaps_mtx);
 331
 332         if (__hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &x, &y))
 333                 goto out;
 334
 335         input_report_abs(input_dev, ABS_X, x - rest_x);
 336         input_report_abs(input_dev, ABS_Y, y - rest_y);
 337         input_sync(input_dev);
 338
 339 out:
 340         mutex_unlock(&hdaps_mtx);
 341 }
 342
 343
 344 /* Sysfs Files */
 345
 346 static ssize_t hdaps_position_show(struct device *dev,
 347                                    struct device_attribute *attr, char *buf)
 348 {
 349         int ret, x, y;
 350
 351         ret = hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &x, &y);
 352         if (ret)
 353                 return ret;
 354
 355         return sprintf(buf, "(%d,%d)\n", x, y);
 356 }
 357
 358 static ssize_t hdaps_variance_show(struct device *dev,
 359                                    struct device_attribute *attr, char *buf)
 360 {
 361         int ret, x, y;
 362
 363         ret = hdaps_read_pair(HDAPS_PORT_XVAR, HDAPS_PORT_YVAR, &x, &y);
 364         if (ret)
 365                 return ret;
 366
 367         return sprintf(buf, "(%d,%d)\n", x, y);
 368 }
 369
 370 static ssize_t hdaps_temp1_show(struct device *dev,
 371                                 struct device_attribute *attr, char *buf)
 372 {
 373         u8 temp;
 374         int ret;
 375
 376         ret = hdaps_readb_one(HDAPS_PORT_TEMP1, &temp);
 377         if (ret < 0)
 378                 return ret;
 379
 380         return sprintf(buf, "%u\n", temp);
 381 }
 382
 383 static ssize_t hdaps_temp2_show(struct device *dev,
 384                                 struct device_attribute *attr, char *buf)
 385 {
 386         u8 temp;
 387         int ret;
 388
 389         ret = hdaps_readb_one(HDAPS_PORT_TEMP2, &temp);
 390         if (ret < 0)
 391                 return ret;
 392
 393         return sprintf(buf, "%u\n", temp);
 394 }
 395
 396 static ssize_t hdaps_keyboard_activity_show(struct device *dev,
 397                                             struct device_attribute *attr,
 398                                             char *buf)
 399 {
 400         return sprintf(buf, "%u\n", KEYBD_ISSET(km_activity));
 401 }
 402
 403 static ssize_t hdaps_mouse_activity_show(struct device *dev,
 404                                          struct device_attribute *attr,
 405                                          char *buf)
 406 {
 407         return sprintf(buf, "%u\n", MOUSE_ISSET(km_activity));
 408 }
 409
 410 static ssize_t hdaps_calibrate_show(struct device *dev,
 411                                     struct device_attribute *attr, char *buf)
 412 {
 413         return sprintf(buf, "(%d,%d)\n", rest_x, rest_y);
 414 }
 415
 416 static ssize_t hdaps_calibrate_store(struct device *dev,
 417                                      struct device_attribute *attr,
 418                                      const char *buf, size_t count)
 419 {
 420         mutex_lock(&hdaps_mtx);
 421         hdaps_calibrate();
 422         mutex_unlock(&hdaps_mtx);
 423
 424         return count;
 425 }
 426
 427 static ssize_t hdaps_invert_show(struct device *dev,
 428                                  struct device_attribute *attr, char *buf)
 429 {
 430         return sprintf(buf, "%u\n", hdaps_invert);
 431 }
 432
 433 static ssize_t hdaps_invert_store(struct device *dev,
 434                                   struct device_attribute *attr,
 435                                   const char *buf, size_t count)
 436 {
 437         int invert;
 438
 439         if (sscanf(buf, "%d", &invert) != 1 || (invert != 1 && invert != 0))
 440                 return -EINVAL;
 441
 442         hdaps_invert = invert;
 443         hdaps_calibrate();
 444
 445         return count;
 446 }
 447
 448 static DEVICE_ATTR(position, 0444, hdaps_position_show, NULL);
 449 static DEVICE_ATTR(variance, 0444, hdaps_variance_show, NULL);
 450 static DEVICE_ATTR(temp1, 0444, hdaps_temp1_show, NULL);
 451 static DEVICE_ATTR(temp2, 0444, hdaps_temp2_show, NULL);
 452 static DEVICE_ATTR(keyboard_activity, 0444, hdaps_keyboard_activity_show, NULL);
 453 static DEVICE_ATTR(mouse_activity, 0444, hdaps_mouse_activity_show, NULL);
 454 static DEVICE_ATTR(calibrate, 0644, hdaps_calibrate_show,hdaps_calibrate_store);
 455 static DEVICE_ATTR(invert, 0644, hdaps_invert_show, hdaps_invert_store);
 456
 457 static struct attribute *hdaps_attributes[] = {
 458         &dev_attr_position.attr,
 459         &dev_attr_variance.attr,
 460         &dev_attr_temp1.attr,
 461         &dev_attr_temp2.attr,
 462         &dev_attr_keyboard_activity.attr,
 463         &dev_attr_mouse_activity.attr,
 464         &dev_attr_calibrate.attr,
 465         &dev_attr_invert.attr,
 466         NULL,
 467 };
 468
 469 static struct attribute_group hdaps_attribute_group = {
 470         .attrs = hdaps_attributes,
 471 };
 472
 473
 474 /* Module stuff */
 475
 476 /* hdaps_dmi_match - found a match.  return one, short-circuiting the hunt. */
 477 static int __init hdaps_dmi_match(const struct dmi_system_id *id)
 478 {
 479         printk(KERN_INFO "hdaps: %s detected.\n", id->ident);
 480         return 1;
 481 }
 482
 483 /* hdaps_dmi_match_invert - found an inverted match. */
 484 static int __init hdaps_dmi_match_invert(const struct dmi_system_id *id)
 485 {
 486         hdaps_invert = 1;
 487         printk(KERN_INFO "hdaps: inverting axis readings.\n");
 488         return hdaps_dmi_match(id);
 489 }
 490
 491 #define HDAPS_DMI_MATCH_NORMAL(vendor, model) {         \
 492         .ident = vendor " " model,                      \
 493         .callback = hdaps_dmi_match,                    \
 494         .matches = {                                    \
 495                 DMI_MATCH(DMI_BOARD_VENDOR, vendor),    \
 496                 DMI_MATCH(DMI_PRODUCT_VERSION, model)   \
 497         }                                               \
 498 }
 499
 500 #define HDAPS_DMI_MATCH_INVERT(vendor, model) {         \
 501         .ident = vendor " " model,                      \
 502         .callback = hdaps_dmi_match_invert,             \
 503         .matches = {                                    \
 504                 DMI_MATCH(DMI_BOARD_VENDOR, vendor),    \
 505                 DMI_MATCH(DMI_PRODUCT_VERSION, model)   \
 506         }                                               \
 507 }
 508
 509 /* Note that HDAPS_DMI_MATCH_NORMAL("ThinkPad T42") would match
 510    "ThinkPad T42p", so the order of the entries matters.
 511    If your ThinkPad is not recognized, please update to latest
 512    BIOS. This is especially the case for some R52 ThinkPads. */
 513 static struct dmi_system_id __initdata hdaps_whitelist[] = {
 514         HDAPS_DMI_MATCH_INVERT("IBM", "ThinkPad R50p"),
 515         HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad R50"),
 516         HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad R51"),
 517         HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad R52"),
 518         HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad R61i"),
 519         HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad R61"),
 520         HDAPS_DMI_MATCH_INVERT("IBM", "ThinkPad T41p"),
 521         HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad T41"),
 522         HDAPS_DMI_MATCH_INVERT("IBM", "ThinkPad T42p"),
 523         HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad T42"),
 524         HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad T43"),
 525         HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad T60"),
 526         HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad T61p"),
 527         HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad T61"),
 528         HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad X40"),
 529         HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad X41"),
 530         HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad X60"),
 531         HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad X61s"),
 532         HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad X61"),
 533         HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad Z60m"),
 534         HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad Z61m"),
 535         HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad Z61p"),
 536         { .ident = NULL }
 537 };
 538
 539 static int __init hdaps_init(void)
 540 {
 541         struct input_dev *idev;
 542         int ret;
 543
 544         if (!dmi_check_system(hdaps_whitelist)) {
 545                 printk(KERN_WARNING "hdaps: supported laptop not found!\n");
 546                 ret = -ENODEV;
 547                 goto out;
 548         }
 549
 550         if (!request_region(HDAPS_LOW_PORT, HDAPS_NR_PORTS, "hdaps")) {
 551                 ret = -ENXIO;
 552                 goto out;
 553         }
 554
 555         ret = platform_driver_register(&hdaps_driver);
 556         if (ret)
 557                 goto out_region;
 558
 559         pdev = platform_device_register_simple("hdaps", -1, NULL, 0);
 560         if (IS_ERR(pdev)) {
 561                 ret = PTR_ERR(pdev);
 562                 goto out_driver;
 563         }
 564
 565         ret = sysfs_create_group(&pdev->dev.kobj, &hdaps_attribute_group);
 566         if (ret)
 567                 goto out_device;
 568
 569         hdaps_idev = input_allocate_polled_device();
 570         if (!hdaps_idev) {
 571                 ret = -ENOMEM;
 572                 goto out_group;
 573         }
 574
 575         hdaps_idev->poll = hdaps_mousedev_poll;
 576         hdaps_idev->poll_interval = HDAPS_POLL_INTERVAL;
 577
 578         /* initial calibrate for the input device */
 579         hdaps_calibrate();
 580
 581         /* initialize the input class */
 582         idev = hdaps_idev->input;
 583         idev->name = "hdaps";
 584         idev->dev.parent = &pdev->dev;
 585         idev->evbit[0] = BIT_MASK(EV_ABS);
 586         input_set_abs_params(idev, ABS_X,
 587                         -256, 256, HDAPS_INPUT_FUZZ, HDAPS_INPUT_FLAT);
 588         input_set_abs_params(idev, ABS_Y,
 589                         -256, 256, HDAPS_INPUT_FUZZ, HDAPS_INPUT_FLAT);
 590
 591         ret = input_register_polled_device(hdaps_idev);
 592         if (ret)
 593                 goto out_idev;
 594
 595         printk(KERN_INFO "hdaps: driver successfully loaded.\n");
 596         return 0;
 597
 598 out_idev:
 599         input_free_polled_device(hdaps_idev);
 600 out_group:
 601         sysfs_remove_group(&pdev->dev.kobj, &hdaps_attribute_group);
 602 out_device:
 603         platform_device_unregister(pdev);
 604 out_driver:
 605         platform_driver_unregister(&hdaps_driver);
 606 out_region:
 607         release_region(HDAPS_LOW_PORT, HDAPS_NR_PORTS);
 608 out:
 609         printk(KERN_WARNING "hdaps: driver init failed (ret=%d)!\n", ret);
 610         return ret;
 611 }
 612
 613 static void __exit hdaps_exit(void)
 614 {
 615         input_unregister_polled_device(hdaps_idev);
 616         input_free_polled_device(hdaps_idev);
 617         sysfs_remove_group(&pdev->dev.kobj, &hdaps_attribute_group);
 618         platform_device_unregister(pdev);
 619         platform_driver_unregister(&hdaps_driver);
 620         release_region(HDAPS_LOW_PORT, HDAPS_NR_PORTS);
 621
 622         printk(KERN_INFO "hdaps: driver unloaded.\n");
 623 }
 624
 625 module_init(hdaps_init);
 626 module_exit(hdaps_exit);
 627
 628 module_param_named(invert, hdaps_invert, bool, 0);
 629 MODULE_PARM_DESC(invert, "invert data along each axis");
 630
 631 MODULE_AUTHOR("Robert Love");
 632 MODULE_DESCRIPTION("IBM Hard Drive Active Protection System (HDAPS) driver");
 633 MODULE_LICENSE("GPL v2");