drivers/input/mousedev.c

   1 /*
   2  * Input driver to ExplorerPS/2 device driver module.
   3  *
   4  * Copyright (c) 1999-2002 Vojtech Pavlik
   5  * Copyright (c) 2004      Dmitry Torokhov
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as published by
   9  * the Free Software Foundation.
  10  */
  11
  12 #define MOUSEDEV_MINOR_BASE     32
  13 #define MOUSEDEV_MINORS         32
  14 #define MOUSEDEV_MIX            31
  15
  16 #include <linux/sched.h>
  17 #include <linux/slab.h>
  18 #include <linux/poll.h>
  19 #include <linux/module.h>
  20 #include <linux/init.h>
  21 #include <linux/input.h>
  22 #include <linux/random.h>
  23 #include <linux/major.h>
  24 #include <linux/device.h>
  25 #include <linux/kernel.h>
  26 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
  27 #include <linux/miscdevice.h>
  28 #endif
  29
  30 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
  31 MODULE_DESCRIPTION("Mouse (ExplorerPS/2) device interfaces");
  32 MODULE_LICENSE("GPL");
  33
  34 #ifndef CONFIG_INPUT_MOUSEDEV_SCREEN_X
  35 #define CONFIG_INPUT_MOUSEDEV_SCREEN_X  1024
  36 #endif
  37 #ifndef CONFIG_INPUT_MOUSEDEV_SCREEN_Y
  38 #define CONFIG_INPUT_MOUSEDEV_SCREEN_Y  768
  39 #endif
  40
  41 static int xres = CONFIG_INPUT_MOUSEDEV_SCREEN_X;
  42 module_param(xres, uint, 0644);
  43 MODULE_PARM_DESC(xres, "Horizontal screen resolution");
  44
  45 static int yres = CONFIG_INPUT_MOUSEDEV_SCREEN_Y;
  46 module_param(yres, uint, 0644);
  47 MODULE_PARM_DESC(yres, "Vertical screen resolution");
  48
  49 static unsigned tap_time = 200;
  50 module_param(tap_time, uint, 0644);
  51 MODULE_PARM_DESC(tap_time, "Tap time for touchpads in absolute mode (msecs)");
  52
  53 struct mousedev_hw_data {
  54         int dx, dy, dz;
  55         int x, y;
  56         int abs_event;
  57         unsigned long buttons;
  58 };
  59
  60 struct mousedev {
  61         int open;
  62         int minor;
  63         struct input_handle handle;
  64         wait_queue_head_t wait;
  65         struct list_head client_list;
  66         spinlock_t client_lock; /* protects client_list */
  67         struct mutex mutex;
  68         struct device dev;
  69         bool exist;
  70
  71         struct list_head mixdev_node;
  72         int mixdev_open;
  73
  74         struct mousedev_hw_data packet;
  75         unsigned int pkt_count;
  76         int old_x[4], old_y[4];
  77         int frac_dx, frac_dy;
  78         unsigned long touch;
  79 };
  80
  81 enum mousedev_emul {
  82         MOUSEDEV_EMUL_PS2,
  83         MOUSEDEV_EMUL_IMPS,
  84         MOUSEDEV_EMUL_EXPS
  85 };
  86
  87 struct mousedev_motion {
  88         int dx, dy, dz;
  89         unsigned long buttons;
  90 };
  91
  92 #define PACKET_QUEUE_LEN        16
  93 struct mousedev_client {
  94         struct fasync_struct *fasync;
  95         struct mousedev *mousedev;
  96         struct list_head node;
  97
  98         struct mousedev_motion packets[PACKET_QUEUE_LEN];
  99         unsigned int head, tail;
 100         spinlock_t packet_lock;
 101         int pos_x, pos_y;
 102
 103         signed char ps2[6];
 104         unsigned char ready, buffer, bufsiz;
 105         unsigned char imexseq, impsseq;
 106         enum mousedev_emul mode;
 107         unsigned long last_buttons;
 108 };
 109
 110 #define MOUSEDEV_SEQ_LEN        6
 111
 112 static unsigned char mousedev_imps_seq[] = { 0xf3, 200, 0xf3, 100, 0xf3, 80 };
 113 static unsigned char mousedev_imex_seq[] = { 0xf3, 200, 0xf3, 200, 0xf3, 80 };
 114
 115 static struct input_handler mousedev_handler;
 116
 117 static struct mousedev *mousedev_table[MOUSEDEV_MINORS];
 118 static DEFINE_MUTEX(mousedev_table_mutex);
 119 static struct mousedev *mousedev_mix;
 120 static LIST_HEAD(mousedev_mix_list);
 121
 122 static void mixdev_open_devices(void);
 123 static void mixdev_close_devices(void);
 124
 125 #define fx(i)  (mousedev->old_x[(mousedev->pkt_count - (i)) & 03])
 126 #define fy(i)  (mousedev->old_y[(mousedev->pkt_count - (i)) & 03])
 127
 128 static void mousedev_touchpad_event(struct input_dev *dev,
 129                                     struct mousedev *mousedev,
 130                                     unsigned int code, int value)
 131 {
 132         int size, tmp;
 133         enum { FRACTION_DENOM = 128 };
 134
 135         switch (code) {
 136
 137         case ABS_X:
 138
 139                 fx(0) = value;
 140                 if (mousedev->touch && mousedev->pkt_count >= 2) {
 141                         size = input_abs_get_min(dev, ABS_X) -
 142                                         input_abs_get_max(dev, ABS_X);
 143                         if (size == 0)
 144                                 size = 256 * 2;
 145
 146                         tmp = ((value - fx(2)) * 256 * FRACTION_DENOM) / size;
 147                         tmp += mousedev->frac_dx;
 148                         mousedev->packet.dx = tmp / FRACTION_DENOM;
 149                         mousedev->frac_dx =
 150                                 tmp - mousedev->packet.dx * FRACTION_DENOM;
 151                 }
 152                 break;
 153
 154         case ABS_Y:
 155                 fy(0) = value;
 156                 if (mousedev->touch && mousedev->pkt_count >= 2) {
 157                         /* use X size for ABS_Y to keep the same scale */
 158                         size = input_abs_get_min(dev, ABS_X) -
 159                                         input_abs_get_max(dev, ABS_X);
 160                         if (size == 0)
 161                                 size = 256 * 2;
 162
 163                         tmp = -((value - fy(2)) * 256 * FRACTION_DENOM) / size;
 164                         tmp += mousedev->frac_dy;
 165                         mousedev->packet.dy = tmp / FRACTION_DENOM;
 166                         mousedev->frac_dy = tmp -
 167                                 mousedev->packet.dy * FRACTION_DENOM;
 168                 }
 169                 break;
 170         }
 171 }
 172
 173 static void mousedev_abs_event(struct input_dev *dev, struct mousedev *mousedev,
 174                                 unsigned int code, int value)
 175 {
 176         int min, max, size;
 177
 178         switch (code) {
 179
 180         case ABS_X:
 181                 min = input_abs_get_min(dev, ABS_X);
 182                 max = input_abs_get_max(dev, ABS_X);
 183
 184                 size = max - min;
 185                 if (size == 0)
 186                         size = xres ? : 1;
 187
 188                 clamp(value, min, max);
 189
 190                 mousedev->packet.x = ((value - min) * xres) / size;
 191                 mousedev->packet.abs_event = 1;
 192                 break;
 193
 194         case ABS_Y:
 195                 min = input_abs_get_min(dev, ABS_Y);
 196                 max = input_abs_get_max(dev, ABS_Y);
 197
 198                 size = max - min;
 199                 if (size == 0)
 200                         size = yres ? : 1;
 201
 202                 clamp(value, min, max);
 203
 204                 mousedev->packet.y = yres - ((value - min) * yres) / size;
 205                 mousedev->packet.abs_event = 1;
 206                 break;
 207         }
 208 }
 209
 210 static void mousedev_rel_event(struct mousedev *mousedev,
 211                                 unsigned int code, int value)
 212 {
 213         switch (code) {
 214         case REL_X:
 215                 mousedev->packet.dx += value;
 216                 break;
 217
 218         case REL_Y:
 219                 mousedev->packet.dy -= value;
 220                 break;
 221
 222         case REL_WHEEL:
 223                 mousedev->packet.dz -= value;
 224                 break;
 225         }
 226 }
 227
 228 static void mousedev_key_event(struct mousedev *mousedev,
 229                                 unsigned int code, int value)
 230 {
 231         int index;
 232
 233         switch (code) {
 234
 235         case BTN_TOUCH:
 236         case BTN_0:
 237         case BTN_LEFT:          index = 0; break;
 238
 239         case BTN_STYLUS:
 240         case BTN_1:
 241         case BTN_RIGHT:         index = 1; break;
 242
 243         case BTN_2:
 244         case BTN_FORWARD:
 245         case BTN_STYLUS2:
 246         case BTN_MIDDLE:        index = 2; break;
 247
 248         case BTN_3:
 249         case BTN_BACK:
 250         case BTN_SIDE:          index = 3; break;
 251
 252         case BTN_4:
 253         case BTN_EXTRA:         index = 4; break;
 254
 255         default:                return;
 256         }
 257
 258         if (value) {
 259                 set_bit(index, &mousedev->packet.buttons);
 260                 set_bit(index, &mousedev_mix->packet.buttons);
 261         } else {
 262                 clear_bit(index, &mousedev->packet.buttons);
 263                 clear_bit(index, &mousedev_mix->packet.buttons);
 264         }
 265 }
 266
 267 static void mousedev_notify_readers(struct mousedev *mousedev,
 268                                     struct mousedev_hw_data *packet)
 269 {
 270         struct mousedev_client *client;
 271         struct mousedev_motion *p;
 272         unsigned int new_head;
 273         int wake_readers = 0;
 274
 275         rcu_read_lock();
 276         list_for_each_entry_rcu(client, &mousedev->client_list, node) {
 277
 278                 /* Just acquire the lock, interrupts already disabled */
 279                 spin_lock(&client->packet_lock);
 280
 281                 p = &client->packets[client->head];
 282                 if (client->ready && p->buttons != mousedev->packet.buttons) {
 283                         new_head = (client->head + 1) % PACKET_QUEUE_LEN;
 284                         if (new_head != client->tail) {
 285                                 p = &client->packets[client->head = new_head];
 286                                 memset(p, 0, sizeof(struct mousedev_motion));
 287                         }
 288                 }
 289
 290                 if (packet->abs_event) {
 291                         p->dx += packet->x - client->pos_x;
 292                         p->dy += packet->y - client->pos_y;
 293                         client->pos_x = packet->x;
 294                         client->pos_y = packet->y;
 295                 }
 296
 297                 client->pos_x += packet->dx;
 298                 client->pos_x = client->pos_x < 0 ?
 299                         0 : (client->pos_x >= xres ? xres : client->pos_x);
 300                 client->pos_y += packet->dy;
 301                 client->pos_y = client->pos_y < 0 ?
 302                         0 : (client->pos_y >= yres ? yres : client->pos_y);
 303
 304                 p->dx += packet->dx;
 305                 p->dy += packet->dy;
 306                 p->dz += packet->dz;
 307                 p->buttons = mousedev->packet.buttons;
 308
 309                 if (p->dx || p->dy || p->dz ||
 310                     p->buttons != client->last_buttons)
 311                         client->ready = 1;
 312
 313                 spin_unlock(&client->packet_lock);
 314
 315                 if (client->ready) {
 316                         kill_fasync(&client->fasync, SIGIO, POLL_IN);
 317                         wake_readers = 1;
 318                 }
 319         }
 320         rcu_read_unlock();
 321
 322         if (wake_readers)
 323                 wake_up_interruptible(&mousedev->wait);
 324 }
 325
 326 static void mousedev_touchpad_touch(struct mousedev *mousedev, int value)
 327 {
 328         if (!value) {
 329                 if (mousedev->touch &&
 330                     time_before(jiffies,
 331                                 mousedev->touch + msecs_to_jiffies(tap_time))) {
 332                         /*
 333                          * Toggle left button to emulate tap.
 334                          * We rely on the fact that mousedev_mix always has 0
 335                          * motion packet so we won't mess current position.
 336                          */
 337                         set_bit(0, &mousedev->packet.buttons);
 338                         set_bit(0, &mousedev_mix->packet.buttons);
 339                         mousedev_notify_readers(mousedev, &mousedev_mix->packet);
 340                         mousedev_notify_readers(mousedev_mix,
 341                                                 &mousedev_mix->packet);
 342                         clear_bit(0, &mousedev->packet.buttons);
 343                         clear_bit(0, &mousedev_mix->packet.buttons);
 344                 }
 345                 mousedev->touch = mousedev->pkt_count = 0;
 346                 mousedev->frac_dx = 0;
 347                 mousedev->frac_dy = 0;
 348
 349         } else if (!mousedev->touch)
 350                 mousedev->touch = jiffies;
 351 }
 352
 353 static void mousedev_event(struct input_handle *handle,
 354                            unsigned int type, unsigned int code, int value)
 355 {
 356         struct mousedev *mousedev = handle->private;
 357
 358         switch (type) {
 359
 360         case EV_ABS:
 361                 /* Ignore joysticks */
 362                 if (test_bit(BTN_TRIGGER, handle->dev->keybit))
 363                         return;
 364
 365                 if (test_bit(BTN_TOOL_FINGER, handle->dev->keybit))
 366                         mousedev_touchpad_event(handle->dev,
 367                                                 mousedev, code, value);
 368                 else
 369                         mousedev_abs_event(handle->dev, mousedev, code, value);
 370
 371                 break;
 372
 373         case EV_REL:
 374                 mousedev_rel_event(mousedev, code, value);
 375                 break;
 376
 377         case EV_KEY:
 378                 if (value != 2) {
 379                         if (code == BTN_TOUCH &&
 380                             test_bit(BTN_TOOL_FINGER, handle->dev->keybit))
 381                                 mousedev_touchpad_touch(mousedev, value);
 382                         else
 383                                 mousedev_key_event(mousedev, code, value);
 384                 }
 385                 break;
 386
 387         case EV_SYN:
 388                 if (code == SYN_REPORT) {
 389                         if (mousedev->touch) {
 390                                 mousedev->pkt_count++;
 391                                 /*
 392                                  * Input system eats duplicate events,
 393                                  * but we need all of them to do correct
 394                                  * averaging so apply present one forward
 395                                  */
 396                                 fx(0) = fx(1);
 397                                 fy(0) = fy(1);
 398                         }
 399
 400                         mousedev_notify_readers(mousedev, &mousedev->packet);
 401                         mousedev_notify_readers(mousedev_mix, &mousedev->packet);
 402
 403                         mousedev->packet.dx = mousedev->packet.dy =
 404                                 mousedev->packet.dz = 0;
 405                         mousedev->packet.abs_event = 0;
 406                 }
 407                 break;
 408         }
 409 }
 410
 411 static int mousedev_fasync(int fd, struct file *file, int on)
 412 {
 413         struct mousedev_client *client = file->private_data;
 414
 415         return fasync_helper(fd, file, on, &client->fasync);
 416 }
 417
 418 static void mousedev_free(struct device *dev)
 419 {
 420         struct mousedev *mousedev = container_of(dev, struct mousedev, dev);
 421
 422         input_put_device(mousedev->handle.dev);
 423         kfree(mousedev);
 424 }
 425
 426 static int mousedev_open_device(struct mousedev *mousedev)
 427 {
 428         int retval;
 429
 430         retval = mutex_lock_interruptible(&mousedev->mutex);
 431         if (retval)
 432                 return retval;
 433
 434         if (mousedev->minor == MOUSEDEV_MIX)
 435                 mixdev_open_devices();
 436         else if (!mousedev->exist)
 437                 retval = -ENODEV;
 438         else if (!mousedev->open++) {
 439                 retval = input_open_device(&mousedev->handle);
 440                 if (retval)
 441                         mousedev->open--;
 442         }
 443
 444         mutex_unlock(&mousedev->mutex);
 445         return retval;
 446 }
 447
 448 static void mousedev_close_device(struct mousedev *mousedev)
 449 {
 450         mutex_lock(&mousedev->mutex);
 451
 452         if (mousedev->minor == MOUSEDEV_MIX)
 453                 mixdev_close_devices();
 454         else if (mousedev->exist && !--mousedev->open)
 455                 input_close_device(&mousedev->handle);
 456
 457         mutex_unlock(&mousedev->mutex);
 458 }
 459
 460 /*
 461  * Open all available devices so they can all be multiplexed in one.
 462  * stream. Note that this function is called with mousedev_mix->mutex
 463  * held.
 464  */
 465 static void mixdev_open_devices(void)
 466 {
 467         struct mousedev *mousedev;
 468
 469         if (mousedev_mix->open++)
 470                 return;
 471
 472         list_for_each_entry(mousedev, &mousedev_mix_list, mixdev_node) {
 473                 if (!mousedev->mixdev_open) {
 474                         if (mousedev_open_device(mousedev))
 475                                 continue;
 476
 477                         mousedev->mixdev_open = 1;
 478                 }
 479         }
 480 }
 481
 482 /*
 483  * Close all devices that were opened as part of multiplexed
 484  * device. Note that this function is called with mousedev_mix->mutex
 485  * held.
 486  */
 487 static void mixdev_close_devices(void)
 488 {
 489         struct mousedev *mousedev;
 490
 491         if (--mousedev_mix->open)
 492                 return;
 493
 494         list_for_each_entry(mousedev, &mousedev_mix_list, mixdev_node) {
 495                 if (mousedev->mixdev_open) {
 496                         mousedev->mixdev_open = 0;
 497                         mousedev_close_device(mousedev);
 498                 }
 499         }
 500 }
 501
 502
 503 static void mousedev_attach_client(struct mousedev *mousedev,
 504                                    struct mousedev_client *client)
 505 {
 506         spin_lock(&mousedev->client_lock);
 507         list_add_tail_rcu(&client->node, &mousedev->client_list);
 508         spin_unlock(&mousedev->client_lock);
 509         synchronize_rcu();
 510 }
 511
 512 static void mousedev_detach_client(struct mousedev *mousedev,
 513                                    struct mousedev_client *client)
 514 {
 515         spin_lock(&mousedev->client_lock);
 516         list_del_rcu(&client->node);
 517         spin_unlock(&mousedev->client_lock);
 518         synchronize_rcu();
 519 }
 520
 521 static int mousedev_release(struct inode *inode, struct file *file)
 522 {
 523         struct mousedev_client *client = file->private_data;
 524         struct mousedev *mousedev = client->mousedev;
 525
 526         mousedev_detach_client(mousedev, client);
 527         kfree(client);
 528
 529         mousedev_close_device(mousedev);
 530         put_device(&mousedev->dev);
 531
 532         return 0;
 533 }
 534
 535 static int mousedev_open(struct inode *inode, struct file *file)
 536 {
 537         struct mousedev_client *client;
 538         struct mousedev *mousedev;
 539         int error;
 540         int i;
 541
 542 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
 543         if (imajor(inode) == MISC_MAJOR)
 544                 i = MOUSEDEV_MIX;
 545         else
 546 #endif
 547                 i = iminor(inode) - MOUSEDEV_MINOR_BASE;
 548
 549         if (i >= MOUSEDEV_MINORS)
 550                 return -ENODEV;
 551
 552         error = mutex_lock_interruptible(&mousedev_table_mutex);
 553         if (error) {
 554                 return error;
 555         }
 556         mousedev = mousedev_table[i];
 557         if (mousedev)
 558                 get_device(&mousedev->dev);
 559         mutex_unlock(&mousedev_table_mutex);
 560
 561         if (!mousedev) {
 562                 return -ENODEV;
 563         }
 564
 565         client = kzalloc(sizeof(struct mousedev_client), GFP_KERNEL);
 566         if (!client) {
 567                 error = -ENOMEM;
 568                 goto err_put_mousedev;
 569         }
 570
 571         spin_lock_init(&client->packet_lock);
 572         client->pos_x = xres / 2;
 573         client->pos_y = yres / 2;
 574         client->mousedev = mousedev;
 575         mousedev_attach_client(mousedev, client);
 576
 577         error = mousedev_open_device(mousedev);
 578         if (error)
 579                 goto err_free_client;
 580
 581         file->private_data = client;
 582         return 0;
 583
 584  err_free_client:
 585         mousedev_detach_client(mousedev, client);
 586         kfree(client);
 587  err_put_mousedev:
 588         put_device(&mousedev->dev);
 589         return error;
 590 }
 591
 592 static inline int mousedev_limit_delta(int delta, int limit)
 593 {
 594         return delta > limit ? limit : (delta < -limit ? -limit : delta);
 595 }
 596
 597 static void mousedev_packet(struct mousedev_client *client,
 598                             signed char *ps2_data)
 599 {
 600         struct mousedev_motion *p = &client->packets[client->tail];
 601
 602         ps2_data[0] = 0x08 |
 603                 ((p->dx < 0) << 4) | ((p->dy < 0) << 5) | (p->buttons & 0x07);
 604         ps2_data[1] = mousedev_limit_delta(p->dx, 127);
 605         ps2_data[2] = mousedev_limit_delta(p->dy, 127);
 606         p->dx -= ps2_data[1];
 607         p->dy -= ps2_data[2];
 608
 609         switch (client->mode) {
 610         case MOUSEDEV_EMUL_EXPS:
 611                 ps2_data[3] = mousedev_limit_delta(p->dz, 7);
 612                 p->dz -= ps2_data[3];
 613                 ps2_data[3] = (ps2_data[3] & 0x0f) | ((p->buttons & 0x18) << 1);
 614                 client->bufsiz = 4;
 615                 break;
 616
 617         case MOUSEDEV_EMUL_IMPS:
 618                 ps2_data[0] |=
 619                         ((p->buttons & 0x10) >> 3) | ((p->buttons & 0x08) >> 1);
 620                 ps2_data[3] = mousedev_limit_delta(p->dz, 127);
 621                 p->dz -= ps2_data[3];
 622                 client->bufsiz = 4;
 623                 break;
 624
 625         case MOUSEDEV_EMUL_PS2:
 626         default:
 627                 ps2_data[0] |=
 628                         ((p->buttons & 0x10) >> 3) | ((p->buttons & 0x08) >> 1);
 629                 p->dz = 0;
 630                 client->bufsiz = 3;
 631                 break;
 632         }
 633
 634         if (!p->dx && !p->dy && !p->dz) {
 635                 if (client->tail == client->head) {
 636                         client->ready = 0;
 637                         client->last_buttons = p->buttons;
 638                 } else
 639                         client->tail = (client->tail + 1) % PACKET_QUEUE_LEN;
 640         }
 641 }
 642
 643 static void mousedev_generate_response(struct mousedev_client *client,
 644                                         int command)
 645 {
 646         client->ps2[0] = 0xfa; /* ACK */
 647
 648         switch (command) {
 649
 650         case 0xeb: /* Poll */
 651                 mousedev_packet(client, &client->ps2[1]);
 652                 client->bufsiz++; /* account for leading ACK */
 653                 break;
 654
 655         case 0xf2: /* Get ID */
 656                 switch (client->mode) {
 657                 case MOUSEDEV_EMUL_PS2:
 658                         client->ps2[1] = 0;
 659                         break;
 660                 case MOUSEDEV_EMUL_IMPS:
 661                         client->ps2[1] = 3;
 662                         break;
 663                 case MOUSEDEV_EMUL_EXPS:
 664                         client->ps2[1] = 4;
 665                         break;
 666                 }
 667                 client->bufsiz = 2;
 668                 break;
 669
 670         case 0xe9: /* Get info */
 671                 client->ps2[1] = 0x60; client->ps2[2] = 3; client->ps2[3] = 200;
 672                 client->bufsiz = 4;
 673                 break;
 674
 675         case 0xff: /* Reset */
 676                 client->impsseq = client->imexseq = 0;
 677                 client->mode = MOUSEDEV_EMUL_PS2;
 678                 client->ps2[1] = 0xaa; client->ps2[2] = 0x00;
 679                 client->bufsiz = 3;
 680                 break;
 681
 682         default:
 683                 client->bufsiz = 1;
 684                 break;
 685         }
 686         client->buffer = client->bufsiz;
 687 }
 688
 689 static ssize_t mousedev_write(struct file *file, const char __user *buffer,
 690                                 size_t count, loff_t *ppos)
 691 {
 692         struct mousedev_client *client = file->private_data;
 693         unsigned char c;
 694         unsigned int i;
 695
 696         for (i = 0; i < count; i++) {
 697
 698                 if (get_user(c, buffer + i))
 699                         return -EFAULT;
 700
 701                 spin_lock_irq(&client->packet_lock);
 702
 703                 if (c == mousedev_imex_seq[client->imexseq]) {
 704                         if (++client->imexseq == MOUSEDEV_SEQ_LEN) {
 705                                 client->imexseq = 0;
 706                                 client->mode = MOUSEDEV_EMUL_EXPS;
 707                         }
 708                 } else
 709                         client->imexseq = 0;
 710
 711                 if (c == mousedev_imps_seq[client->impsseq]) {
 712                         if (++client->impsseq == MOUSEDEV_SEQ_LEN) {
 713                                 client->impsseq = 0;
 714                                 client->mode = MOUSEDEV_EMUL_IMPS;
 715                         }
 716                 } else
 717                         client->impsseq = 0;
 718
 719                 mousedev_generate_response(client, c);
 720
 721                 spin_unlock_irq(&client->packet_lock);
 722         }
 723
 724         kill_fasync(&client->fasync, SIGIO, POLL_IN);
 725         wake_up_interruptible(&client->mousedev->wait);
 726
 727         return count;
 728 }
 729
 730 static ssize_t mousedev_read(struct file *file, char __user *buffer,
 731                              size_t count, loff_t *ppos)
 732 {
 733         struct mousedev_client *client = file->private_data;
 734         struct mousedev *mousedev = client->mousedev;
 735         signed char data[sizeof(client->ps2)];
 736         int retval = 0;
 737
 738         if (!client->ready && !client->buffer && mousedev->exist &&
 739             (file->f_flags & O_NONBLOCK))
 740                 return -EAGAIN;
 741
 742         retval = wait_event_interruptible(mousedev->wait,
 743                         !mousedev->exist || client->ready || client->buffer);
 744         if (retval)
 745                 return retval;
 746
 747         if (!mousedev->exist)
 748                 return -ENODEV;
 749
 750         spin_lock_irq(&client->packet_lock);
 751
 752         if (!client->buffer && client->ready) {
 753                 mousedev_packet(client, client->ps2);
 754                 client->buffer = client->bufsiz;
 755         }
 756
 757         if (count > client->buffer)
 758                 count = client->buffer;
 759
 760         memcpy(data, client->ps2 + client->bufsiz - client->buffer, count);
 761         client->buffer -= count;
 762
 763         spin_unlock_irq(&client->packet_lock);
 764
 765         if (copy_to_user(buffer, data, count))
 766                 return -EFAULT;
 767
 768         return count;
 769 }
 770
 771 /* No kernel lock - fine */
 772 static unsigned int mousedev_poll(struct file *file, poll_table *wait)
 773 {
 774         struct mousedev_client *client = file->private_data;
 775         struct mousedev *mousedev = client->mousedev;
 776         unsigned int mask;
 777
 778         poll_wait(file, &mousedev->wait, wait);
 779
 780         mask = mousedev->exist ? POLLOUT | POLLWRNORM : POLLHUP | POLLERR;
 781         if (client->ready || client->buffer)
 782                 mask |= POLLIN | POLLRDNORM;
 783
 784         return mask;
 785 }
 786
 787 static const struct file_operations mousedev_fops = {
 788         .owner =        THIS_MODULE,
 789         .read =         mousedev_read,
 790         .write =        mousedev_write,
 791         .poll =         mousedev_poll,
 792         .open =         mousedev_open,
 793         .release =      mousedev_release,
 794         .fasync =       mousedev_fasync,
 795 };
 796
 797 static int mousedev_install_chrdev(struct mousedev *mousedev)
 798 {
 799         mousedev_table[mousedev->minor] = mousedev;
 800         return 0;
 801 }
 802
 803 static void mousedev_remove_chrdev(struct mousedev *mousedev)
 804 {
 805         mutex_lock(&mousedev_table_mutex);
 806         mousedev_table[mousedev->minor] = NULL;
 807         mutex_unlock(&mousedev_table_mutex);
 808 }
 809
 810 /*
 811  * Mark device non-existent. This disables writes, ioctls and
 812  * prevents new users from opening the device. Already posted
 813  * blocking reads will stay, however new ones will fail.
 814  */
 815 static void mousedev_mark_dead(struct mousedev *mousedev)
 816 {
 817         mutex_lock(&mousedev->mutex);
 818         mousedev->exist = false;
 819         mutex_unlock(&mousedev->mutex);
 820 }
 821
 822 /*
 823  * Wake up users waiting for IO so they can disconnect from
 824  * dead device.
 825  */
 826 static void mousedev_hangup(struct mousedev *mousedev)
 827 {
 828         struct mousedev_client *client;
 829
 830         spin_lock(&mousedev->client_lock);
 831         list_for_each_entry(client, &mousedev->client_list, node)
 832                 kill_fasync(&client->fasync, SIGIO, POLL_HUP);
 833         spin_unlock(&mousedev->client_lock);
 834
 835         wake_up_interruptible(&mousedev->wait);
 836 }
 837
 838 static void mousedev_cleanup(struct mousedev *mousedev)
 839 {
 840         struct input_handle *handle = &mousedev->handle;
 841
 842         mousedev_mark_dead(mousedev);
 843         mousedev_hangup(mousedev);
 844         mousedev_remove_chrdev(mousedev);
 845
 846         /* mousedev is marked dead so no one else accesses mousedev->open */
 847         if (mousedev->open)
 848                 input_close_device(handle);
 849 }
 850
 851 static struct mousedev *mousedev_create(struct input_dev *dev,
 852                                         struct input_handler *handler,
 853                                         int minor)
 854 {
 855         struct mousedev *mousedev;
 856         int error;
 857
 858         mousedev = kzalloc(sizeof(struct mousedev), GFP_KERNEL);
 859         if (!mousedev) {
 860                 error = -ENOMEM;
 861                 goto err_out;
 862         }
 863
 864         INIT_LIST_HEAD(&mousedev->client_list);
 865         INIT_LIST_HEAD(&mousedev->mixdev_node);
 866         spin_lock_init(&mousedev->client_lock);
 867         mutex_init(&mousedev->mutex);
 868         lockdep_set_subclass(&mousedev->mutex,
 869                              minor == MOUSEDEV_MIX ? MOUSEDEV_MIX : 0);
 870         init_waitqueue_head(&mousedev->wait);
 871
 872         if (minor == MOUSEDEV_MIX)
 873                 dev_set_name(&mousedev->dev, "mice");
 874         else
 875                 dev_set_name(&mousedev->dev, "mouse%d", minor);
 876
 877         mousedev->minor = minor;
 878         mousedev->exist = true;
 879         mousedev->handle.dev = input_get_device(dev);
 880         mousedev->handle.name = dev_name(&mousedev->dev);
 881         mousedev->handle.handler = handler;
 882         mousedev->handle.private = mousedev;
 883
 884         mousedev->dev.class = &input_class;
 885         if (dev)
 886                 mousedev->dev.parent = &dev->dev;
 887         mousedev->dev.devt = MKDEV(INPUT_MAJOR, MOUSEDEV_MINOR_BASE + minor);
 888         mousedev->dev.release = mousedev_free;
 889         device_initialize(&mousedev->dev);
 890
 891         if (minor != MOUSEDEV_MIX) {
 892                 error = input_register_handle(&mousedev->handle);
 893                 if (error)
 894                         goto err_free_mousedev;
 895         }
 896
 897         error = mousedev_install_chrdev(mousedev);
 898         if (error)
 899                 goto err_unregister_handle;
 900
 901         error = device_add(&mousedev->dev);
 902         if (error)
 903                 goto err_cleanup_mousedev;
 904
 905         return mousedev;
 906
 907  err_cleanup_mousedev:
 908         mousedev_cleanup(mousedev);
 909  err_unregister_handle:
 910         if (minor != MOUSEDEV_MIX)
 911                 input_unregister_handle(&mousedev->handle);
 912  err_free_mousedev:
 913         put_device(&mousedev->dev);
 914  err_out:
 915         return ERR_PTR(error);
 916 }
 917
 918 static void mousedev_destroy(struct mousedev *mousedev)
 919 {
 920         device_del(&mousedev->dev);
 921         mousedev_cleanup(mousedev);
 922         if (mousedev->minor != MOUSEDEV_MIX)
 923                 input_unregister_handle(&mousedev->handle);
 924         put_device(&mousedev->dev);
 925 }
 926
 927 static int mixdev_add_device(struct mousedev *mousedev)
 928 {
 929         int retval;
 930
 931         retval = mutex_lock_interruptible(&mousedev_mix->mutex);
 932         if (retval)
 933                 return retval;
 934
 935         if (mousedev_mix->open) {
 936                 retval = mousedev_open_device(mousedev);
 937                 if (retval)
 938                         goto out;
 939
 940                 mousedev->mixdev_open = 1;
 941         }
 942
 943         get_device(&mousedev->dev);
 944         list_add_tail(&mousedev->mixdev_node, &mousedev_mix_list);
 945
 946  out:
 947         mutex_unlock(&mousedev_mix->mutex);
 948         return retval;
 949 }
 950
 951 static void mixdev_remove_device(struct mousedev *mousedev)
 952 {
 953         mutex_lock(&mousedev_mix->mutex);
 954
 955         if (mousedev->mixdev_open) {
 956                 mousedev->mixdev_open = 0;
 957                 mousedev_close_device(mousedev);
 958         }
 959
 960         list_del_init(&mousedev->mixdev_node);
 961         mutex_unlock(&mousedev_mix->mutex);
 962
 963         put_device(&mousedev->dev);
 964 }
 965
 966 static int mousedev_connect(struct input_handler *handler,
 967                             struct input_dev *dev,
 968                             const struct input_device_id *id)
 969 {
 970         struct mousedev *mousedev;
 971         int minor;
 972         int error;
 973
 974         for (minor = 0; minor < MOUSEDEV_MINORS; minor++)
 975                 if (!mousedev_table[minor])
 976                         break;
 977
 978         if (minor == MOUSEDEV_MINORS) {
 979                 printk(KERN_ERR "mousedev: no more free mousedev devices\n");
 980                 return -ENFILE;
 981         }
 982
 983         mousedev = mousedev_create(dev, handler, minor);
 984         if (IS_ERR(mousedev))
 985                 return PTR_ERR(mousedev);
 986
 987         error = mixdev_add_device(mousedev);
 988         if (error) {
 989                 mousedev_destroy(mousedev);
 990                 return error;
 991         }
 992
 993         return 0;
 994 }
 995
 996 static void mousedev_disconnect(struct input_handle *handle)
 997 {
 998         struct mousedev *mousedev = handle->private;
 999
1000         mixdev_remove_device(mousedev);
1001         mousedev_destroy(mousedev);
1002 }
1003
1004 static const struct input_device_id mousedev_ids[] = {
1005         {
1006                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1007                                 INPUT_DEVICE_ID_MATCH_KEYBIT |
1008                                 INPUT_DEVICE_ID_MATCH_RELBIT,
1009                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_REL) },
1010                 .keybit = { [BIT_WORD(BTN_LEFT)] = BIT_MASK(BTN_LEFT) },
1011                 .relbit = { BIT_MASK(REL_X) | BIT_MASK(REL_Y) },
1012         },      /* A mouse like device, at least one button,
1013                    two relative axes */
1014         {
1015                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1016                                 INPUT_DEVICE_ID_MATCH_RELBIT,
1017                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_REL) },
1018                 .relbit = { BIT_MASK(REL_WHEEL) },
1019         },      /* A separate scrollwheel */
1020         {
1021                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1022                                 INPUT_DEVICE_ID_MATCH_KEYBIT |
1023                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
1024                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS) },
1025                 .keybit = { [BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH) },
1026                 .absbit = { BIT_MASK(ABS_X) | BIT_MASK(ABS_Y) },
1027         },      /* A tablet like device, at least touch detection,
1028                    two absolute axes */
1029         {
1030                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1031                                 INPUT_DEVICE_ID_MATCH_KEYBIT |
1032                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
1033                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS) },
1034                 .keybit = { [BIT_WORD(BTN_TOOL_FINGER)] =
1035                                 BIT_MASK(BTN_TOOL_FINGER) },
1036                 .absbit = { BIT_MASK(ABS_X) | BIT_MASK(ABS_Y) |
1037                                 BIT_MASK(ABS_PRESSURE) |
1038                                 BIT_MASK(ABS_TOOL_WIDTH) },
1039         },      /* A touchpad */
1040         {
1041                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1042                         INPUT_DEVICE_ID_MATCH_KEYBIT |
1043                         INPUT_DEVICE_ID_MATCH_ABSBIT,
1044                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS) },
1045                 .keybit = { [BIT_WORD(BTN_LEFT)] = BIT_MASK(BTN_LEFT) },
1046                 .absbit = { BIT_MASK(ABS_X) | BIT_MASK(ABS_Y) },
1047         },      /* Mouse-like device with absolute X and Y but ordinary
1048                    clicks, like hp ILO2 High Performance mouse */
1049
1050         { },    /* Terminating entry */
1051 };
1052
1053 MODULE_DEVICE_TABLE(input, mousedev_ids);
1054
1055 static struct input_handler mousedev_handler = {
1056         .event =        mousedev_event,
1057         .connect =      mousedev_connect,
1058         .disconnect =   mousedev_disconnect,
1059         .fops =         &mousedev_fops,
1060         .minor =        MOUSEDEV_MINOR_BASE,
1061         .name =         "mousedev",
1062         .id_table =     mousedev_ids,
1063 };
1064
1065 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
1066 static struct miscdevice psaux_mouse = {
1067         PSMOUSE_MINOR, "psaux", &mousedev_fops
1068 };
1069 static int psaux_registered;
1070 #endif
1071
1072 static int __init mousedev_init(void)
1073 {
1074         int error;
1075
1076         mousedev_mix = mousedev_create(NULL, &mousedev_handler, MOUSEDEV_MIX);
1077         if (IS_ERR(mousedev_mix))
1078                 return PTR_ERR(mousedev_mix);
1079
1080         error = input_register_handler(&mousedev_handler);
1081         if (error) {
1082                 mousedev_destroy(mousedev_mix);
1083                 return error;
1084         }
1085
1086 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
1087         error = misc_register(&psaux_mouse);
1088         if (error)
1089                 printk(KERN_WARNING "mice: could not register psaux device, "
1090                         "error: %d\n", error);
1091         else
1092                 psaux_registered = 1;
1093 #endif
1094
1095         printk(KERN_INFO "mice: PS/2 mouse device common for all mice\n");
1096
1097         return 0;
1098 }
1099
1100 static void __exit mousedev_exit(void)
1101 {
1102 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
1103         if (psaux_registered)
1104                 misc_deregister(&psaux_mouse);
1105 #endif
1106         input_unregister_handler(&mousedev_handler);
1107         mousedev_destroy(mousedev_mix);
1108 }
1109
1110 module_init(mousedev_init);
1111 module_exit(mousedev_exit);