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