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 #include <linux/io.h>
  39
  40 #define HDAPS_LOW_PORT          0x1600  /* first port used by hdaps */
  41 #define HDAPS_NR_PORTS          0x30    /* number of ports: 0x1600 - 0x162f */
  42
  43 #define HDAPS_PORT_STATE        0x1611  /* device state */
  44 #define HDAPS_PORT_YPOS         0x1612  /* y-axis position */
  45 #define HDAPS_PORT_XPOS         0x1614  /* x-axis position */
  46 #define HDAPS_PORT_TEMP1        0x1616  /* device temperature, in Celsius */
  47 #define HDAPS_PORT_YVAR         0x1617  /* y-axis variance (what is this?) */
  48 #define HDAPS_PORT_XVAR         0x1619  /* x-axis variance (what is this?) */
  49 #define HDAPS_PORT_TEMP2        0x161b  /* device temperature (again?) */
  50 #define HDAPS_PORT_UNKNOWN      0x161c  /* what is this? */
  51 #define HDAPS_PORT_KMACT        0x161d  /* keyboard or mouse activity */
  52
  53 #define STATE_FRESH             0x50    /* accelerometer data is fresh */
  54
  55 #define KEYBD_MASK              0x20    /* set if keyboard activity */
  56 #define MOUSE_MASK              0x40    /* set if mouse activity */
  57 #define KEYBD_ISSET(n)          (!! (n & KEYBD_MASK))   /* keyboard used? */
  58 #define MOUSE_ISSET(n)          (!! (n & MOUSE_MASK))   /* mouse used? */
  59
  60 #define INIT_TIMEOUT_MSECS      4000    /* wait up to 4s for device init ... */
  61 #define INIT_WAIT_MSECS         200     /* ... in 200ms increments */
  62
  63 #define HDAPS_POLL_INTERVAL     50      /* poll for input every 1/20s (50 ms)*/
  64 #define HDAPS_INPUT_FUZZ        4       /* input event threshold */
  65 #define HDAPS_INPUT_FLAT        4
  66
  67 #define HDAPS_X_AXIS            (1 << 0)
  68 #define HDAPS_Y_AXIS            (1 << 1)
  69 #define HDAPS_BOTH_AXES         (HDAPS_X_AXIS | HDAPS_Y_AXIS)
  70
  71 static struct platform_device *pdev;
  72 static struct input_polled_dev *hdaps_idev;
  73 static unsigned int hdaps_invert;
  74 static u8 km_activity;
  75 static int rest_x;
  76 static int rest_y;
  77
  78 static DEFINE_MUTEX(hdaps_mtx);
  79
  80 /*
  81  * __get_latch - Get the value from a given port.  Callers must hold hdaps_mtx.
  82  */
  83 static inline u8 __get_latch(u16 port)
  84 {
  85         return inb(port) & 0xff;
  86 }
  87
  88 /*
  89  * __check_latch - Check a port latch for a given value.  Returns zero if the
  90  * port contains the given value.  Callers must hold hdaps_mtx.
  91  */
  92 static inline int __check_latch(u16 port, u8 val)
  93 {
  94         if (__get_latch(port) == val)
  95                 return 0;
  96         return -EINVAL;
  97 }
  98
  99 /*
 100  * __wait_latch - Wait up to 100us for a port latch to get a certain value,
 101  * returning zero if the value is obtained.  Callers must hold hdaps_mtx.
 102  */
 103 static int __wait_latch(u16 port, u8 val)
 104 {
 105         unsigned int i;
 106
 107         for (i = 0; i < 20; i++) {
 108                 if (!__check_latch(port, val))
 109                         return 0;
 110                 udelay(5);
 111         }
 112
 113         return -EIO;
 114 }
 115
 116 /*
 117  * __device_refresh - request a refresh from the accelerometer.  Does not wait
 118  * for refresh to complete.  Callers must hold hdaps_mtx.
 119  */
 120 static void __device_refresh(void)
 121 {
 122         udelay(200);
 123         if (inb(0x1604) != STATE_FRESH) {
 124                 outb(0x11, 0x1610);
 125                 outb(0x01, 0x161f);
 126         }
 127 }
 128
 129 /*
 130  * __device_refresh_sync - request a synchronous refresh from the
 131  * accelerometer.  We wait for the refresh to complete.  Returns zero if
 132  * successful and nonzero on error.  Callers must hold hdaps_mtx.
 133  */
 134 static int __device_refresh_sync(void)
 135 {
 136         __device_refresh();
 137         return __wait_latch(0x1604, STATE_FRESH);
 138 }
 139
 140 /*
 141  * __device_complete - indicate to the accelerometer that we are done reading
 142  * data, and then initiate an async refresh.  Callers must hold hdaps_mtx.
 143  */
 144 static inline void __device_complete(void)
 145 {
 146         inb(0x161f);
 147         inb(0x1604);
 148         __device_refresh();
 149 }
 150
 151 /*
 152  * hdaps_readb_one - reads a byte from a single I/O port, placing the value in
 153  * the given pointer.  Returns zero on success or a negative error on failure.
 154  * Can sleep.
 155  */
 156 static int hdaps_readb_one(unsigned int port, u8 *val)
 157 {
 158         int ret;
 159
 160         mutex_lock(&hdaps_mtx);
 161
 162         /* do a sync refresh -- we need to be sure that we read fresh data */
 163         ret = __device_refresh_sync();
 164         if (ret)
 165                 goto out;
 166
 167         *val = inb(port);
 168         __device_complete();
 169
 170 out:
 171         mutex_unlock(&hdaps_mtx);
 172         return ret;
 173 }
 174
 175 /* __hdaps_read_pair - internal lockless helper for hdaps_read_pair(). */
 176 static int __hdaps_read_pair(unsigned int port1, unsigned int port2,
 177                              int *x, int *y)
 178 {
 179         /* do a sync refresh -- we need to be sure that we read fresh data */
 180         if (__device_refresh_sync())
 181                 return -EIO;
 182
 183         *y = inw(port2);
 184         *x = inw(port1);
 185         km_activity = inb(HDAPS_PORT_KMACT);
 186         __device_complete();
 187
 188         /* hdaps_invert is a bitvector to negate the axes */
 189         if (hdaps_invert & HDAPS_X_AXIS)
 190                 *x = -*x;
 191         if (hdaps_invert & HDAPS_Y_AXIS)
 192                 *y = -*y;
 193
 194         return 0;
 195 }
 196
 197 /*
 198  * hdaps_read_pair - reads the values from a pair of ports, placing the values
 199  * in the given pointers.  Returns zero on success.  Can sleep.
 200  */
 201 static int hdaps_read_pair(unsigned int port1, unsigned int port2,
 202                            int *val1, int *val2)
 203 {
 204         int ret;
 205
 206         mutex_lock(&hdaps_mtx);
 207         ret = __hdaps_read_pair(port1, port2, val1, val2);
 208         mutex_unlock(&hdaps_mtx);
 209
 210         return ret;
 211 }
 212
 213 /*
 214  * hdaps_device_init - initialize the accelerometer.  Returns zero on success
 215  * and negative error code on failure.  Can sleep.
 216  */
 217 static int hdaps_device_init(void)
 218 {
 219         int total, ret = -ENXIO;
 220
 221         mutex_lock(&hdaps_mtx);
 222
 223         outb(0x13, 0x1610);
 224         outb(0x01, 0x161f);
 225         if (__wait_latch(0x161f, 0x00))
 226                 goto out;
 227
 228         /*
 229          * Most ThinkPads return 0x01.
 230          *
 231          * Others--namely the R50p, T41p, and T42p--return 0x03.  These laptops
 232          * have "inverted" axises.
 233          *
 234          * The 0x02 value occurs when the chip has been previously initialized.
 235          */
 236         if (__check_latch(0x1611, 0x03) &&
 237                      __check_latch(0x1611, 0x02) &&
 238                      __check_latch(0x1611, 0x01))
 239                 goto out;
 240
 241         printk(KERN_DEBUG "hdaps: initial latch check good (0x%02x).\n",
 242                __get_latch(0x1611));
 243
 244         outb(0x17, 0x1610);
 245         outb(0x81, 0x1611);
 246         outb(0x01, 0x161f);
 247         if (__wait_latch(0x161f, 0x00))
 248                 goto out;
 249         if (__wait_latch(0x1611, 0x00))
 250                 goto out;
 251         if (__wait_latch(0x1612, 0x60))
 252                 goto out;
 253         if (__wait_latch(0x1613, 0x00))
 254                 goto out;
 255         outb(0x14, 0x1610);
 256         outb(0x01, 0x1611);
 257         outb(0x01, 0x161f);
 258         if (__wait_latch(0x161f, 0x00))
 259                 goto out;
 260         outb(0x10, 0x1610);
 261         outb(0xc8, 0x1611);
 262         outb(0x00, 0x1612);
 263         outb(0x02, 0x1613);
 264         outb(0x01, 0x161f);
 265         if (__wait_latch(0x161f, 0x00))
 266                 goto out;
 267         if (__device_refresh_sync())
 268                 goto out;
 269         if (__wait_latch(0x1611, 0x00))
 270                 goto out;
 271
 272         /* we have done our dance, now let's wait for the applause */
 273         for (total = INIT_TIMEOUT_MSECS; total > 0; total -= INIT_WAIT_MSECS) {
 274                 int x, y;
 275
 276                 /* a read of the device helps push it into action */
 277                 __hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &x, &y);
 278                 if (!__wait_latch(0x1611, 0x02)) {
 279                         ret = 0;
 280                         break;
 281                 }
 282
 283                 msleep(INIT_WAIT_MSECS);
 284         }
 285
 286 out:
 287         mutex_unlock(&hdaps_mtx);
 288         return ret;
 289 }
 290
 291
 292 /* Device model stuff */
 293
 294 static int hdaps_probe(struct platform_device *dev)
 295 {
 296         int ret;
 297
 298         ret = hdaps_device_init();
 299         if (ret)
 300                 return ret;
 301
 302         printk(KERN_INFO "hdaps: device successfully initialized.\n");
 303         return 0;
 304 }
 305
 306 static int hdaps_resume(struct platform_device *dev)
 307 {
 308         return hdaps_device_init();
 309 }
 310
 311 static struct platform_driver hdaps_driver = {
 312         .probe = hdaps_probe,
 313         .resume = hdaps_resume,
 314         .driver = {
 315                 .name = "hdaps",
 316                 .owner = THIS_MODULE,
 317         },
 318 };
 319
 320 /*
 321  * hdaps_calibrate - Set our "resting" values.  Callers must hold hdaps_mtx.
 322  */
 323 static void hdaps_calibrate(void)
 324 {
 325         __hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &rest_x, &rest_y);
 326 }
 327
 328 static void hdaps_mousedev_poll(struct input_polled_dev *dev)
 329 {
 330         struct input_dev *input_dev = dev->input;
 331         int x, y;
 332
 333         mutex_lock(&hdaps_mtx);
 334
 335         if (__hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &x, &y))
 336                 goto out;
 337
 338         input_report_abs(input_dev, ABS_X, x - rest_x);
 339         input_report_abs(input_dev, ABS_Y, y - rest_y);
 340         input_sync(input_dev);
 341
 342 out:
 343         mutex_unlock(&hdaps_mtx);
 344 }
 345
 346
 347 /* Sysfs Files */
 348
 349 static ssize_t hdaps_position_show(struct device *dev,
 350                                    struct device_attribute *attr, char *buf)
 351 {
 352         int ret, x, y;
 353
 354         ret = hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &x, &y);
 355         if (ret)
 356                 return ret;
 357
 358         return sprintf(buf, "(%d,%d)\n", x, y);
 359 }
 360
 361 static ssize_t hdaps_variance_show(struct device *dev,
 362                                    struct device_attribute *attr, char *buf)
 363 {
 364         int ret, x, y;
 365
 366         ret = hdaps_read_pair(HDAPS_PORT_XVAR, HDAPS_PORT_YVAR, &x, &y);
 367         if (ret)
 368                 return ret;
 369
 370         return sprintf(buf, "(%d,%d)\n", x, y);
 371 }
 372
 373 static ssize_t hdaps_temp1_show(struct device *dev,
 374                                 struct device_attribute *attr, char *buf)
 375 {
 376         u8 temp;
 377         int ret;
 378
 379         ret = hdaps_readb_one(HDAPS_PORT_TEMP1, &temp);
 380         if (ret < 0)
 381                 return ret;
 382
 383         return sprintf(buf, "%u\n", temp);
 384 }
 385
 386 static ssize_t hdaps_temp2_show(struct device *dev,
 387                                 struct device_attribute *attr, char *buf)
 388 {
 389         u8 temp;
 390         int ret;
 391
 392         ret = hdaps_readb_one(HDAPS_PORT_TEMP2, &temp);
 393         if (ret < 0)
 394                 return ret;
 395
 396         return sprintf(buf, "%u\n", temp);
 397 }
 398
 399 static ssize_t hdaps_keyboard_activity_show(struct device *dev,
 400                                             struct device_attribute *attr,
 401                                             char *buf)
 402 {
 403         return sprintf(buf, "%u\n", KEYBD_ISSET(km_activity));
 404 }
 405
 406 static ssize_t hdaps_mouse_activity_show(struct device *dev,
 407                                          struct device_attribute *attr,
 408                                          char *buf)
 409 {
 410         return sprintf(buf, "%u\n", MOUSE_ISSET(km_activity));
 411 }
 412
 413 static ssize_t hdaps_calibrate_show(struct device *dev,
 414                                     struct device_attribute *attr, char *buf)
 415 {
 416         return sprintf(buf, "(%d,%d)\n", rest_x, rest_y);
 417 }
 418
 419 static ssize_t hdaps_calibrate_store(struct device *dev,
 420                                      struct device_attribute *attr,
 421                                      const char *buf, size_t count)
 422 {
 423         mutex_lock(&hdaps_mtx);
 424         hdaps_calibrate();
 425         mutex_unlock(&hdaps_mtx);
 426
 427         return count;
 428 }
 429
 430 static ssize_t hdaps_invert_show(struct device *dev,
 431                                  struct device_attribute *attr, char *buf)
 432 {
 433         return sprintf(buf, "%u\n", hdaps_invert);
 434 }
 435
 436 static ssize_t hdaps_invert_store(struct device *dev,
 437                                   struct device_attribute *attr,
 438                                   const char *buf, size_t count)
 439 {
 440         int invert;
 441
 442         if (sscanf(buf, "%d", &invert) != 1 ||
 443             invert < 0 || invert > HDAPS_BOTH_AXES)
 444                 return -EINVAL;
 445
 446         hdaps_invert = invert;
 447         hdaps_calibrate();
 448
 449         return count;
 450 }
 451
 452 static DEVICE_ATTR(position, 0444, hdaps_position_show, NULL);
 453 static DEVICE_ATTR(variance, 0444, hdaps_variance_show, NULL);
 454 static DEVICE_ATTR(temp1, 0444, hdaps_temp1_show, NULL);
 455 static DEVICE_ATTR(temp2, 0444, hdaps_temp2_show, NULL);
 456 static DEVICE_ATTR(keyboard_activity, 0444, hdaps_keyboard_activity_show, NULL);
 457 static DEVICE_ATTR(mouse_activity, 0444, hdaps_mouse_activity_show, NULL);
 458 static DEVICE_ATTR(calibrate, 0644, hdaps_calibrate_show,hdaps_calibrate_store);
 459 static DEVICE_ATTR(invert, 0644, hdaps_invert_show, hdaps_invert_store);
 460
 461 static struct attribute *hdaps_attributes[] = {
 462         &dev_attr_position.attr,
 463         &dev_attr_variance.attr,
 464         &dev_attr_temp1.attr,
 465         &dev_attr_temp2.attr,
 466         &dev_attr_keyboard_activity.attr,
 467         &dev_attr_mouse_activity.attr,
 468         &dev_attr_calibrate.attr,
 469         &dev_attr_invert.attr,
 470         NULL,
 471 };
 472
 473 static struct attribute_group hdaps_attribute_group = {
 474         .attrs = hdaps_attributes,
 475 };
 476
 477
 478 /* Module stuff */
 479
 480 /* hdaps_dmi_match - found a match.  return one, short-circuiting the hunt. */
 481 static int __init hdaps_dmi_match(const struct dmi_system_id *id)
 482 {
 483         printk(KERN_INFO "hdaps: %s detected.\n", id->ident);
 484         return 1;
 485 }
 486
 487 /* hdaps_dmi_match_invert - found an inverted match. */
 488 static int __init hdaps_dmi_match_invert(const struct dmi_system_id *id)
 489 {
 490         hdaps_invert = (unsigned long)id->driver_data;
 491         printk(KERN_INFO "hdaps: inverting axis (%u) readings.\n",
 492                hdaps_invert);
 493         return hdaps_dmi_match(id);
 494 }
 495
 496 #define HDAPS_DMI_MATCH_INVERT(vendor, model, axes) {   \
 497         .ident = vendor " " model,                      \
 498         .callback = hdaps_dmi_match_invert,             \
 499         .driver_data = (void *)axes,                    \
 500         .matches = {                                    \
 501                 DMI_MATCH(DMI_BOARD_VENDOR, vendor),    \
 502                 DMI_MATCH(DMI_PRODUCT_VERSION, model)   \
 503         }                                               \
 504 }
 505
 506 #define HDAPS_DMI_MATCH_NORMAL(vendor, model)           \
 507         HDAPS_DMI_MATCH_INVERT(vendor, model, 0)
 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", HDAPS_BOTH_AXES),
 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", HDAPS_BOTH_AXES),
 519         HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad R61", HDAPS_BOTH_AXES),
 520         HDAPS_DMI_MATCH_INVERT("IBM", "ThinkPad T41p", HDAPS_BOTH_AXES),
 521         HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad T41"),
 522         HDAPS_DMI_MATCH_INVERT("IBM", "ThinkPad T42p", HDAPS_BOTH_AXES),
 523         HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad T42"),
 524         HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad T43"),
 525         HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad T60", HDAPS_BOTH_AXES),
 526         HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad T61p", HDAPS_BOTH_AXES),
 527         HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad T61", HDAPS_BOTH_AXES),
 528         HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad X40"),
 529         HDAPS_DMI_MATCH_INVERT("IBM", "ThinkPad X41", HDAPS_Y_AXIS),
 530         HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad X60", HDAPS_BOTH_AXES),
 531         HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad X61s", HDAPS_BOTH_AXES),
 532         HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad X61", HDAPS_BOTH_AXES),
 533         HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad Z60m"),
 534         HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad Z61m", HDAPS_BOTH_AXES),
 535         HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad Z61p", HDAPS_BOTH_AXES),
 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->phys = "isa1600/input0";
 585         idev->id.bustype = BUS_ISA;
 586         idev->dev.parent = &pdev->dev;
 587         idev->evbit[0] = BIT_MASK(EV_ABS);
 588         input_set_abs_params(idev, ABS_X,
 589                         -256, 256, HDAPS_INPUT_FUZZ, HDAPS_INPUT_FLAT);
 590         input_set_abs_params(idev, ABS_Y,
 591                         -256, 256, HDAPS_INPUT_FUZZ, HDAPS_INPUT_FLAT);
 592
 593         ret = input_register_polled_device(hdaps_idev);
 594         if (ret)
 595                 goto out_idev;
 596
 597         printk(KERN_INFO "hdaps: driver successfully loaded.\n");
 598         return 0;
 599
 600 out_idev:
 601         input_free_polled_device(hdaps_idev);
 602 out_group:
 603         sysfs_remove_group(&pdev->dev.kobj, &hdaps_attribute_group);
 604 out_device:
 605         platform_device_unregister(pdev);
 606 out_driver:
 607         platform_driver_unregister(&hdaps_driver);
 608 out_region:
 609         release_region(HDAPS_LOW_PORT, HDAPS_NR_PORTS);
 610 out:
 611         printk(KERN_WARNING "hdaps: driver init failed (ret=%d)!\n", ret);
 612         return ret;
 613 }
 614
 615 static void __exit hdaps_exit(void)
 616 {
 617         input_unregister_polled_device(hdaps_idev);
 618         input_free_polled_device(hdaps_idev);
 619         sysfs_remove_group(&pdev->dev.kobj, &hdaps_attribute_group);
 620         platform_device_unregister(pdev);
 621         platform_driver_unregister(&hdaps_driver);
 622         release_region(HDAPS_LOW_PORT, HDAPS_NR_PORTS);
 623
 624         printk(KERN_INFO "hdaps: driver unloaded.\n");
 625 }
 626
 627 module_init(hdaps_init);
 628 module_exit(hdaps_exit);
 629
 630 module_param_named(invert, hdaps_invert, int, 0);
 631 MODULE_PARM_DESC(invert, "invert data along each axis. 1 invert x-axis, "
 632                  "2 invert y-axis, 3 invert both axes.");
 633
 634 MODULE_AUTHOR("Robert Love");
 635 MODULE_DESCRIPTION("IBM Hard Drive Active Protection System (HDAPS) driver");
 636 MODULE_LICENSE("GPL v2");