drivers/platform/x86/hdaps.c

   1 /*
   2  * 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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  30
  31 #include <linux/delay.h>
  32 #include <linux/platform_device.h>
  33 #include <linux/input-polldev.h>
  34 #include <linux/kernel.h>
  35 #include <linux/mutex.h>
  36 #include <linux/module.h>
  37 #include <linux/timer.h>
  38 #include <linux/dmi.h>
  39 #include <linux/jiffies.h>
  40 #include <linux/io.h>
  41
  42 #define HDAPS_LOW_PORT          0x1600  /* first port used by hdaps */
  43 #define HDAPS_NR_PORTS          0x30    /* number of ports: 0x1600 - 0x162f */
  44
  45 #define HDAPS_PORT_STATE        0x1611  /* device state */
  46 #define HDAPS_PORT_YPOS         0x1612  /* y-axis position */
  47 #define HDAPS_PORT_XPOS         0x1614  /* x-axis position */
  48 #define HDAPS_PORT_TEMP1        0x1616  /* device temperature, in Celsius */
  49 #define HDAPS_PORT_YVAR         0x1617  /* y-axis variance (what is this?) */
  50 #define HDAPS_PORT_XVAR         0x1619  /* x-axis variance (what is this?) */
  51 #define HDAPS_PORT_TEMP2        0x161b  /* device temperature (again?) */
  52 #define HDAPS_PORT_UNKNOWN      0x161c  /* what is this? */
  53 #define HDAPS_PORT_KMACT        0x161d  /* keyboard or mouse activity */
  54
  55 #define STATE_FRESH             0x50    /* accelerometer data is fresh */
  56
  57 #define KEYBD_MASK              0x20    /* set if keyboard activity */
  58 #define MOUSE_MASK              0x40    /* set if mouse activity */
  59 #define KEYBD_ISSET(n)          (!! (n & KEYBD_MASK))   /* keyboard used? */
  60 #define MOUSE_ISSET(n)          (!! (n & MOUSE_MASK))   /* mouse used? */
  61
  62 #define INIT_TIMEOUT_MSECS      4000    /* wait up to 4s for device init ... */
  63 #define INIT_WAIT_MSECS         200     /* ... in 200ms increments */
  64
  65 #define HDAPS_POLL_INTERVAL     50      /* poll for input every 1/20s (50 ms)*/
  66 #define HDAPS_INPUT_FUZZ        4       /* input event threshold */
  67 #define HDAPS_INPUT_FLAT        4
  68
  69 #define HDAPS_X_AXIS            (1 << 0)
  70 #define HDAPS_Y_AXIS            (1 << 1)
  71 #define HDAPS_BOTH_AXES         (HDAPS_X_AXIS | HDAPS_Y_AXIS)
  72
  73 static struct platform_device *pdev;
  74 static struct input_polled_dev *hdaps_idev;
  75 static unsigned int hdaps_invert;
  76 static u8 km_activity;
  77 static int rest_x;
  78 static int rest_y;
  79
  80 static DEFINE_MUTEX(hdaps_mtx);
  81
  82 /*
  83  * __get_latch - Get the value from a given port.  Callers must hold hdaps_mtx.
  84  */
  85 static inline u8 __get_latch(u16 port)
  86 {
  87         return inb(port) & 0xff;
  88 }
  89
  90 /*
  91  * __check_latch - Check a port latch for a given value.  Returns zero if the
  92  * port contains the given value.  Callers must hold hdaps_mtx.
  93  */
  94 static inline int __check_latch(u16 port, u8 val)
  95 {
  96         if (__get_latch(port) == val)
  97                 return 0;
  98         return -EINVAL;
  99 }
 100
 101 /*
 102  * __wait_latch - Wait up to 100us for a port latch to get a certain value,
 103  * returning zero if the value is obtained.  Callers must hold hdaps_mtx.
 104  */
 105 static int __wait_latch(u16 port, u8 val)
 106 {
 107         unsigned int i;
 108
 109         for (i = 0; i < 20; i++) {
 110                 if (!__check_latch(port, val))
 111                         return 0;
 112                 udelay(5);
 113         }
 114
 115         return -EIO;
 116 }
 117
 118 /*
 119  * __device_refresh - request a refresh from the accelerometer.  Does not wait
 120  * for refresh to complete.  Callers must hold hdaps_mtx.
 121  */
 122 static void __device_refresh(void)
 123 {
 124         udelay(200);
 125         if (inb(0x1604) != STATE_FRESH) {
 126                 outb(0x11, 0x1610);
 127                 outb(0x01, 0x161f);
 128         }
 129 }
 130
 131 /*
 132  * __device_refresh_sync - request a synchronous refresh from the
 133  * accelerometer.  We wait for the refresh to complete.  Returns zero if
 134  * successful and nonzero on error.  Callers must hold hdaps_mtx.
 135  */
 136 static int __device_refresh_sync(void)
 137 {
 138         __device_refresh();
 139         return __wait_latch(0x1604, STATE_FRESH);
 140 }
 141
 142 /*
 143  * __device_complete - indicate to the accelerometer that we are done reading
 144  * data, and then initiate an async refresh.  Callers must hold hdaps_mtx.
 145  */
 146 static inline void __device_complete(void)
 147 {
 148         inb(0x161f);
 149         inb(0x1604);
 150         __device_refresh();
 151 }
 152
 153 /*
 154  * hdaps_readb_one - reads a byte from a single I/O port, placing the value in
 155  * the given pointer.  Returns zero on success or a negative error on failure.
 156  * Can sleep.
 157  */
 158 static int hdaps_readb_one(unsigned int port, u8 *val)
 159 {
 160         int ret;
 161
 162         mutex_lock(&hdaps_mtx);
 163
 164         /* do a sync refresh -- we need to be sure that we read fresh data */
 165         ret = __device_refresh_sync();
 166         if (ret)
 167                 goto out;
 168
 169         *val = inb(port);
 170         __device_complete();
 171
 172 out:
 173         mutex_unlock(&hdaps_mtx);
 174         return ret;
 175 }
 176
 177 /* __hdaps_read_pair - internal lockless helper for hdaps_read_pair(). */
 178 static int __hdaps_read_pair(unsigned int port1, unsigned int port2,
 179                              int *x, int *y)
 180 {
 181         /* do a sync refresh -- we need to be sure that we read fresh data */
 182         if (__device_refresh_sync())
 183                 return -EIO;
 184
 185         *y = inw(port2);
 186         *x = inw(port1);
 187         km_activity = inb(HDAPS_PORT_KMACT);
 188         __device_complete();
 189
 190         /* hdaps_invert is a bitvector to negate the axes */
 191         if (hdaps_invert & HDAPS_X_AXIS)
 192                 *x = -*x;
 193         if (hdaps_invert & HDAPS_Y_AXIS)
 194                 *y = -*y;
 195
 196         return 0;
 197 }
 198
 199 /*
 200  * hdaps_read_pair - reads the values from a pair of ports, placing the values
 201  * in the given pointers.  Returns zero on success.  Can sleep.
 202  */
 203 static int hdaps_read_pair(unsigned int port1, unsigned int port2,
 204                            int *val1, int *val2)
 205 {
 206         int ret;
 207
 208         mutex_lock(&hdaps_mtx);
 209         ret = __hdaps_read_pair(port1, port2, val1, val2);
 210         mutex_unlock(&hdaps_mtx);
 211
 212         return ret;
 213 }
 214
 215 /*
 216  * hdaps_device_init - initialize the accelerometer.  Returns zero on success
 217  * and negative error code on failure.  Can sleep.
 218  */
 219 static int hdaps_device_init(void)
 220 {
 221         int total, ret = -ENXIO;
 222
 223         mutex_lock(&hdaps_mtx);
 224
 225         outb(0x13, 0x1610);
 226         outb(0x01, 0x161f);
 227         if (__wait_latch(0x161f, 0x00))
 228                 goto out;
 229
 230         /*
 231          * Most ThinkPads return 0x01.
 232          *
 233          * Others--namely the R50p, T41p, and T42p--return 0x03.  These laptops
 234          * have "inverted" axises.
 235          *
 236          * The 0x02 value occurs when the chip has been previously initialized.
 237          */
 238         if (__check_latch(0x1611, 0x03) &&
 239                      __check_latch(0x1611, 0x02) &&
 240                      __check_latch(0x1611, 0x01))
 241                 goto out;
 242
 243         printk(KERN_DEBUG "hdaps: initial latch check good (0x%02x)\n",
 244                __get_latch(0x1611));
 245
 246         outb(0x17, 0x1610);
 247         outb(0x81, 0x1611);
 248         outb(0x01, 0x161f);
 249         if (__wait_latch(0x161f, 0x00))
 250                 goto out;
 251         if (__wait_latch(0x1611, 0x00))
 252                 goto out;
 253         if (__wait_latch(0x1612, 0x60))
 254                 goto out;
 255         if (__wait_latch(0x1613, 0x00))
 256                 goto out;
 257         outb(0x14, 0x1610);
 258         outb(0x01, 0x1611);
 259         outb(0x01, 0x161f);
 260         if (__wait_latch(0x161f, 0x00))
 261                 goto out;
 262         outb(0x10, 0x1610);
 263         outb(0xc8, 0x1611);
 264         outb(0x00, 0x1612);
 265         outb(0x02, 0x1613);
 266         outb(0x01, 0x161f);
 267         if (__wait_latch(0x161f, 0x00))
 268                 goto out;
 269         if (__device_refresh_sync())
 270                 goto out;
 271         if (__wait_latch(0x1611, 0x00))
 272                 goto out;
 273
 274         /* we have done our dance, now let's wait for the applause */
 275         for (total = INIT_TIMEOUT_MSECS; total > 0; total -= INIT_WAIT_MSECS) {
 276                 int x, y;
 277
 278                 /* a read of the device helps push it into action */
 279                 __hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &x, &y);
 280                 if (!__wait_latch(0x1611, 0x02)) {
 281                         ret = 0;
 282                         break;
 283                 }
 284
 285                 msleep(INIT_WAIT_MSECS);
 286         }
 287
 288 out:
 289         mutex_unlock(&hdaps_mtx);
 290         return ret;
 291 }
 292
 293
 294 /* Device model stuff */
 295
 296 static int hdaps_probe(struct platform_device *dev)
 297 {
 298         int ret;
 299
 300         ret = hdaps_device_init();
 301         if (ret)
 302                 return ret;
 303
 304         pr_info("device successfully initialized\n");
 305         return 0;
 306 }
 307
 308 static int hdaps_resume(struct platform_device *dev)
 309 {
 310         return hdaps_device_init();
 311 }
 312
 313 static struct platform_driver hdaps_driver = {
 314         .probe = hdaps_probe,
 315         .resume = hdaps_resume,
 316         .driver = {
 317                 .name = "hdaps",
 318                 .owner = THIS_MODULE,
 319         },
 320 };
 321
 322 /*
 323  * hdaps_calibrate - Set our "resting" values.  Callers must hold hdaps_mtx.
 324  */
 325 static void hdaps_calibrate(void)
 326 {
 327         __hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &rest_x, &rest_y);
 328 }
 329
 330 static void hdaps_mousedev_poll(struct input_polled_dev *dev)
 331 {
 332         struct input_dev *input_dev = dev->input;
 333         int x, y;
 334
 335         mutex_lock(&hdaps_mtx);
 336
 337         if (__hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &x, &y))
 338                 goto out;
 339
 340         input_report_abs(input_dev, ABS_X, x - rest_x);
 341         input_report_abs(input_dev, ABS_Y, y - rest_y);
 342         input_sync(input_dev);
 343
 344 out:
 345         mutex_unlock(&hdaps_mtx);
 346 }
 347
 348
 349 /* Sysfs Files */
 350
 351 static ssize_t hdaps_position_show(struct device *dev,
 352                                    struct device_attribute *attr, char *buf)
 353 {
 354         int ret, x, y;
 355
 356         ret = hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &x, &y);
 357         if (ret)
 358                 return ret;
 359
 360         return sprintf(buf, "(%d,%d)\n", x, y);
 361 }
 362
 363 static ssize_t hdaps_variance_show(struct device *dev,
 364                                    struct device_attribute *attr, char *buf)
 365 {
 366         int ret, x, y;
 367
 368         ret = hdaps_read_pair(HDAPS_PORT_XVAR, HDAPS_PORT_YVAR, &x, &y);
 369         if (ret)
 370                 return ret;
 371
 372         return sprintf(buf, "(%d,%d)\n", x, y);
 373 }
 374
 375 static ssize_t hdaps_temp1_show(struct device *dev,
 376                                 struct device_attribute *attr, char *buf)
 377 {
 378         u8 temp;
 379         int ret;
 380
 381         ret = hdaps_readb_one(HDAPS_PORT_TEMP1, &temp);
 382         if (ret < 0)
 383                 return ret;
 384
 385         return sprintf(buf, "%u\n", temp);
 386 }
 387
 388 static ssize_t hdaps_temp2_show(struct device *dev,
 389                                 struct device_attribute *attr, char *buf)
 390 {
 391         u8 temp;
 392         int ret;
 393
 394         ret = hdaps_readb_one(HDAPS_PORT_TEMP2, &temp);
 395         if (ret < 0)
 396                 return ret;
 397
 398         return sprintf(buf, "%u\n", temp);
 399 }
 400
 401 static ssize_t hdaps_keyboard_activity_show(struct device *dev,
 402                                             struct device_attribute *attr,
 403                                             char *buf)
 404 {
 405         return sprintf(buf, "%u\n", KEYBD_ISSET(km_activity));
 406 }
 407
 408 static ssize_t hdaps_mouse_activity_show(struct device *dev,
 409                                          struct device_attribute *attr,
 410                                          char *buf)
 411 {
 412         return sprintf(buf, "%u\n", MOUSE_ISSET(km_activity));
 413 }
 414
 415 static ssize_t hdaps_calibrate_show(struct device *dev,
 416                                     struct device_attribute *attr, char *buf)
 417 {
 418         return sprintf(buf, "(%d,%d)\n", rest_x, rest_y);
 419 }
 420
 421 static ssize_t hdaps_calibrate_store(struct device *dev,
 422                                      struct device_attribute *attr,
 423                                      const char *buf, size_t count)
 424 {
 425         mutex_lock(&hdaps_mtx);
 426         hdaps_calibrate();
 427         mutex_unlock(&hdaps_mtx);
 428
 429         return count;
 430 }
 431
 432 static ssize_t hdaps_invert_show(struct device *dev,
 433                                  struct device_attribute *attr, char *buf)
 434 {
 435         return sprintf(buf, "%u\n", hdaps_invert);
 436 }
 437
 438 static ssize_t hdaps_invert_store(struct device *dev,
 439                                   struct device_attribute *attr,
 440                                   const char *buf, size_t count)
 441 {
 442         int invert;
 443
 444         if (sscanf(buf, "%d", &invert) != 1 ||
 445             invert < 0 || invert > HDAPS_BOTH_AXES)
 446                 return -EINVAL;
 447
 448         hdaps_invert = invert;
 449         hdaps_calibrate();
 450
 451         return count;
 452 }
 453
 454 static DEVICE_ATTR(position, 0444, hdaps_position_show, NULL);
 455 static DEVICE_ATTR(variance, 0444, hdaps_variance_show, NULL);
 456 static DEVICE_ATTR(temp1, 0444, hdaps_temp1_show, NULL);
 457 static DEVICE_ATTR(temp2, 0444, hdaps_temp2_show, NULL);
 458 static DEVICE_ATTR(keyboard_activity, 0444, hdaps_keyboard_activity_show, NULL);
 459 static DEVICE_ATTR(mouse_activity, 0444, hdaps_mouse_activity_show, NULL);
 460 static DEVICE_ATTR(calibrate, 0644, hdaps_calibrate_show,hdaps_calibrate_store);
 461 static DEVICE_ATTR(invert, 0644, hdaps_invert_show, hdaps_invert_store);
 462
 463 static struct attribute *hdaps_attributes[] = {
 464         &dev_attr_position.attr,
 465         &dev_attr_variance.attr,
 466         &dev_attr_temp1.attr,
 467         &dev_attr_temp2.attr,
 468         &dev_attr_keyboard_activity.attr,
 469         &dev_attr_mouse_activity.attr,
 470         &dev_attr_calibrate.attr,
 471         &dev_attr_invert.attr,
 472         NULL,
 473 };
 474
 475 static struct attribute_group hdaps_attribute_group = {
 476         .attrs = hdaps_attributes,
 477 };
 478
 479
 480 /* Module stuff */
 481
 482 /* hdaps_dmi_match - found a match.  return one, short-circuiting the hunt. */
 483 static int __init hdaps_dmi_match(const struct dmi_system_id *id)
 484 {
 485         pr_info("%s detected\n", id->ident);
 486         return 1;
 487 }
 488
 489 /* hdaps_dmi_match_invert - found an inverted match. */
 490 static int __init hdaps_dmi_match_invert(const struct dmi_system_id *id)
 491 {
 492         hdaps_invert = (unsigned long)id->driver_data;
 493         pr_info("inverting axis (%u) readings\n", hdaps_invert);
 494         return hdaps_dmi_match(id);
 495 }
 496
 497 #define HDAPS_DMI_MATCH_INVERT(vendor, model, axes) {   \
 498         .ident = vendor " " model,                      \
 499         .callback = hdaps_dmi_match_invert,             \
 500         .driver_data = (void *)axes,                    \
 501         .matches = {                                    \
 502                 DMI_MATCH(DMI_BOARD_VENDOR, vendor),    \
 503                 DMI_MATCH(DMI_PRODUCT_VERSION, model)   \
 504         }                                               \
 505 }
 506
 507 #define HDAPS_DMI_MATCH_NORMAL(vendor, model)           \
 508         HDAPS_DMI_MATCH_INVERT(vendor, model, 0)
 509
 510 /* Note that HDAPS_DMI_MATCH_NORMAL("ThinkPad T42") would match
 511    "ThinkPad T42p", so the order of the entries matters.
 512    If your ThinkPad is not recognized, please update to latest
 513    BIOS. This is especially the case for some R52 ThinkPads. */
 514 static struct dmi_system_id __initdata hdaps_whitelist[] = {
 515         HDAPS_DMI_MATCH_INVERT("IBM", "ThinkPad R50p", HDAPS_BOTH_AXES),
 516         HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad R50"),
 517         HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad R51"),
 518         HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad R52"),
 519         HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad R61i", HDAPS_BOTH_AXES),
 520         HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad R61", HDAPS_BOTH_AXES),
 521         HDAPS_DMI_MATCH_INVERT("IBM", "ThinkPad T41p", HDAPS_BOTH_AXES),
 522         HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad T41"),
 523         HDAPS_DMI_MATCH_INVERT("IBM", "ThinkPad T42p", HDAPS_BOTH_AXES),
 524         HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad T42"),
 525         HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad T43"),
 526         HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad T400", HDAPS_BOTH_AXES),
 527         HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad T60", HDAPS_BOTH_AXES),
 528         HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad T61p", HDAPS_BOTH_AXES),
 529         HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad T61", HDAPS_BOTH_AXES),
 530         HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad X40"),
 531         HDAPS_DMI_MATCH_INVERT("IBM", "ThinkPad X41", HDAPS_Y_AXIS),
 532         HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad X60", HDAPS_BOTH_AXES),
 533         HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad X61s", HDAPS_BOTH_AXES),
 534         HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad X61", HDAPS_BOTH_AXES),
 535         HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad Z60m"),
 536         HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad Z61m", HDAPS_BOTH_AXES),
 537         HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad Z61p", HDAPS_BOTH_AXES),
 538         { .ident = NULL }
 539 };
 540
 541 static int __init hdaps_init(void)
 542 {
 543         struct input_dev *idev;
 544         int ret;
 545
 546         if (!dmi_check_system(hdaps_whitelist)) {
 547                 pr_warn("supported laptop not found!\n");
 548                 ret = -ENODEV;
 549                 goto out;
 550         }
 551
 552         if (!request_region(HDAPS_LOW_PORT, HDAPS_NR_PORTS, "hdaps")) {
 553                 ret = -ENXIO;
 554                 goto out;
 555         }
 556
 557         ret = platform_driver_register(&hdaps_driver);
 558         if (ret)
 559                 goto out_region;
 560
 561         pdev = platform_device_register_simple("hdaps", -1, NULL, 0);
 562         if (IS_ERR(pdev)) {
 563                 ret = PTR_ERR(pdev);
 564                 goto out_driver;
 565         }
 566
 567         ret = sysfs_create_group(&pdev->dev.kobj, &hdaps_attribute_group);
 568         if (ret)
 569                 goto out_device;
 570
 571         hdaps_idev = input_allocate_polled_device();
 572         if (!hdaps_idev) {
 573                 ret = -ENOMEM;
 574                 goto out_group;
 575         }
 576
 577         hdaps_idev->poll = hdaps_mousedev_poll;
 578         hdaps_idev->poll_interval = HDAPS_POLL_INTERVAL;
 579
 580         /* initial calibrate for the input device */
 581         hdaps_calibrate();
 582
 583         /* initialize the input class */
 584         idev = hdaps_idev->input;
 585         idev->name = "hdaps";
 586         idev->phys = "isa1600/input0";
 587         idev->id.bustype = BUS_ISA;
 588         idev->dev.parent = &pdev->dev;
 589         idev->evbit[0] = BIT_MASK(EV_ABS);
 590         input_set_abs_params(idev, ABS_X,
 591                         -256, 256, HDAPS_INPUT_FUZZ, HDAPS_INPUT_FLAT);
 592         input_set_abs_params(idev, ABS_Y,
 593                         -256, 256, HDAPS_INPUT_FUZZ, HDAPS_INPUT_FLAT);
 594
 595         ret = input_register_polled_device(hdaps_idev);
 596         if (ret)
 597                 goto out_idev;
 598
 599         pr_info("driver successfully loaded\n");
 600         return 0;
 601
 602 out_idev:
 603         input_free_polled_device(hdaps_idev);
 604 out_group:
 605         sysfs_remove_group(&pdev->dev.kobj, &hdaps_attribute_group);
 606 out_device:
 607         platform_device_unregister(pdev);
 608 out_driver:
 609         platform_driver_unregister(&hdaps_driver);
 610 out_region:
 611         release_region(HDAPS_LOW_PORT, HDAPS_NR_PORTS);
 612 out:
 613         pr_warn("driver init failed (ret=%d)!\n", ret);
 614         return ret;
 615 }
 616
 617 static void __exit hdaps_exit(void)
 618 {
 619         input_unregister_polled_device(hdaps_idev);
 620         input_free_polled_device(hdaps_idev);
 621         sysfs_remove_group(&pdev->dev.kobj, &hdaps_attribute_group);
 622         platform_device_unregister(pdev);
 623         platform_driver_unregister(&hdaps_driver);
 624         release_region(HDAPS_LOW_PORT, HDAPS_NR_PORTS);
 625
 626         pr_info("driver unloaded\n");
 627 }
 628
 629 module_init(hdaps_init);
 630 module_exit(hdaps_exit);
 631
 632 module_param_named(invert, hdaps_invert, int, 0);
 633 MODULE_PARM_DESC(invert, "invert data along each axis. 1 invert x-axis, "
 634                  "2 invert y-axis, 3 invert both axes.");
 635
 636 MODULE_AUTHOR("Robert Love");
 637 MODULE_DESCRIPTION("IBM Hard Drive Active Protection System (HDAPS) driver");
 638 MODULE_LICENSE("GPL v2");