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/smp_lock.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 #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         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
  70         struct list_head mixdev_node;
  71         int mixdev_open;
  72
  73         struct mousedev_hw_data packet;
  74         unsigned int pkt_count;
  75         int old_x[4], old_y[4];
  76         int frac_dx, frac_dy;
  77         unsigned long touch;
  78 };
  79
  80 enum mousedev_emul {
  81         MOUSEDEV_EMUL_PS2,
  82         MOUSEDEV_EMUL_IMPS,
  83         MOUSEDEV_EMUL_EXPS
  84 };
  85
  86 struct mousedev_motion {
  87         int dx, dy, dz;
  88         unsigned long buttons;
  89 };
  90
  91 #define PACKET_QUEUE_LEN        16
  92 struct mousedev_client {
  93         struct fasync_struct *fasync;
  94         struct mousedev *mousedev;
  95         struct list_head node;
  96
  97         struct mousedev_motion packets[PACKET_QUEUE_LEN];
  98         unsigned int head, tail;
  99         spinlock_t packet_lock;
 100         int pos_x, pos_y;
 101
 102         signed char ps2[6];
 103         unsigned char ready, buffer, bufsiz;
 104         unsigned char imexseq, impsseq;
 105         enum mousedev_emul mode;
 106         unsigned long last_buttons;
 107 };
 108
 109 #define MOUSEDEV_SEQ_LEN        6
 110
 111 static unsigned char mousedev_imps_seq[] = { 0xf3, 200, 0xf3, 100, 0xf3, 80 };
 112 static unsigned char mousedev_imex_seq[] = { 0xf3, 200, 0xf3, 200, 0xf3, 80 };
 113
 114 static struct input_handler mousedev_handler;
 115
 116 static struct mousedev *mousedev_table[MOUSEDEV_MINORS];
 117 static DEFINE_MUTEX(mousedev_table_mutex);
 118 static struct mousedev *mousedev_mix;
 119 static LIST_HEAD(mousedev_mix_list);
 120
 121 static void mixdev_open_devices(void);
 122 static void mixdev_close_devices(void);
 123
 124 #define fx(i)  (mousedev->old_x[(mousedev->pkt_count - (i)) & 03])
 125 #define fy(i)  (mousedev->old_y[(mousedev->pkt_count - (i)) & 03])
 126
 127 static void mousedev_touchpad_event(struct input_dev *dev,
 128                                     struct mousedev *mousedev,
 129                                     unsigned int code, int value)
 130 {
 131         int size, tmp;
 132         enum { FRACTION_DENOM = 128 };
 133
 134         switch (code) {
 135
 136         case ABS_X:
 137                 fx(0) = value;
 138                 if (mousedev->touch && mousedev->pkt_count >= 2) {
 139                         size = dev->absmax[ABS_X] - dev->absmin[ABS_X];
 140                         if (size == 0)
 141                                 size = 256 * 2;
 142                         tmp = ((value - fx(2)) * 256 * FRACTION_DENOM) / size;
 143                         tmp += mousedev->frac_dx;
 144                         mousedev->packet.dx = tmp / FRACTION_DENOM;
 145                         mousedev->frac_dx =
 146                                 tmp - mousedev->packet.dx * FRACTION_DENOM;
 147                 }
 148                 break;
 149
 150         case ABS_Y:
 151                 fy(0) = value;
 152                 if (mousedev->touch && mousedev->pkt_count >= 2) {
 153                         /* use X size to keep the same scale */
 154                         size = dev->absmax[ABS_X] - dev->absmin[ABS_X];
 155                         if (size == 0)
 156                                 size = 256 * 2;
 157                         tmp = -((value - fy(2)) * 256 * FRACTION_DENOM) / size;
 158                         tmp += mousedev->frac_dy;
 159                         mousedev->packet.dy = tmp / FRACTION_DENOM;
 160                         mousedev->frac_dy = tmp -
 161                                 mousedev->packet.dy * FRACTION_DENOM;
 162                 }
 163                 break;
 164         }
 165 }
 166
 167 static void mousedev_abs_event(struct input_dev *dev, struct mousedev *mousedev,
 168                                 unsigned int code, int value)
 169 {
 170         int size;
 171
 172         switch (code) {
 173
 174         case ABS_X:
 175                 size = dev->absmax[ABS_X] - dev->absmin[ABS_X];
 176                 if (size == 0)
 177                         size = xres ? : 1;
 178                 if (value > dev->absmax[ABS_X])
 179                         value = dev->absmax[ABS_X];
 180                 if (value < dev->absmin[ABS_X])
 181                         value = dev->absmin[ABS_X];
 182                 mousedev->packet.x =
 183                         ((value - dev->absmin[ABS_X]) * xres) / size;
 184                 mousedev->packet.abs_event = 1;
 185                 break;
 186
 187         case ABS_Y:
 188                 size = dev->absmax[ABS_Y] - dev->absmin[ABS_Y];
 189                 if (size == 0)
 190                         size = yres ? : 1;
 191                 if (value > dev->absmax[ABS_Y])
 192                         value = dev->absmax[ABS_Y];
 193                 if (value < dev->absmin[ABS_Y])
 194                         value = dev->absmin[ABS_Y];
 195                 mousedev->packet.y = yres -
 196                         ((value - dev->absmin[ABS_Y]) * yres) / size;
 197                 mousedev->packet.abs_event = 1;
 198                 break;
 199         }
 200 }
 201
 202 static void mousedev_rel_event(struct mousedev *mousedev,
 203                                 unsigned int code, int value)
 204 {
 205         switch (code) {
 206         case REL_X:
 207                 mousedev->packet.dx += value;
 208                 break;
 209
 210         case REL_Y:
 211                 mousedev->packet.dy -= value;
 212                 break;
 213
 214         case REL_WHEEL:
 215                 mousedev->packet.dz -= value;
 216                 break;
 217         }
 218 }
 219
 220 static void mousedev_key_event(struct mousedev *mousedev,
 221                                 unsigned int code, int value)
 222 {
 223         int index;
 224
 225         switch (code) {
 226
 227         case BTN_TOUCH:
 228         case BTN_0:
 229         case BTN_LEFT:          index = 0; break;
 230
 231         case BTN_STYLUS:
 232         case BTN_1:
 233         case BTN_RIGHT:         index = 1; break;
 234
 235         case BTN_2:
 236         case BTN_FORWARD:
 237         case BTN_STYLUS2:
 238         case BTN_MIDDLE:        index = 2; break;
 239
 240         case BTN_3:
 241         case BTN_BACK:
 242         case BTN_SIDE:          index = 3; break;
 243
 244         case BTN_4:
 245         case BTN_EXTRA:         index = 4; break;
 246
 247         default:                return;
 248         }
 249
 250         if (value) {
 251                 set_bit(index, &mousedev->packet.buttons);
 252                 set_bit(index, &mousedev_mix->packet.buttons);
 253         } else {
 254                 clear_bit(index, &mousedev->packet.buttons);
 255                 clear_bit(index, &mousedev_mix->packet.buttons);
 256         }
 257 }
 258
 259 static void mousedev_notify_readers(struct mousedev *mousedev,
 260                                     struct mousedev_hw_data *packet)
 261 {
 262         struct mousedev_client *client;
 263         struct mousedev_motion *p;
 264         unsigned int new_head;
 265         int wake_readers = 0;
 266
 267         rcu_read_lock();
 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         rcu_read_unlock();
 313
 314         if (wake_readers)
 315                 wake_up_interruptible(&mousedev->wait);
 316 }
 317
 318 static void mousedev_touchpad_touch(struct mousedev *mousedev, int value)
 319 {
 320         if (!value) {
 321                 if (mousedev->touch &&
 322                     time_before(jiffies,
 323                                 mousedev->touch + msecs_to_jiffies(tap_time))) {
 324                         /*
 325                          * Toggle left button to emulate tap.
 326                          * We rely on the fact that mousedev_mix always has 0
 327                          * motion packet so we won't mess current position.
 328                          */
 329                         set_bit(0, &mousedev->packet.buttons);
 330                         set_bit(0, &mousedev_mix->packet.buttons);
 331                         mousedev_notify_readers(mousedev, &mousedev_mix->packet);
 332                         mousedev_notify_readers(mousedev_mix,
 333                                                 &mousedev_mix->packet);
 334                         clear_bit(0, &mousedev->packet.buttons);
 335                         clear_bit(0, &mousedev_mix->packet.buttons);
 336                 }
 337                 mousedev->touch = mousedev->pkt_count = 0;
 338                 mousedev->frac_dx = 0;
 339                 mousedev->frac_dy = 0;
 340
 341         } else if (!mousedev->touch)
 342                 mousedev->touch = jiffies;
 343 }
 344
 345 static void mousedev_event(struct input_handle *handle,
 346                            unsigned int type, unsigned int code, int value)
 347 {
 348         struct mousedev *mousedev = handle->private;
 349
 350         switch (type) {
 351
 352         case EV_ABS:
 353                 /* Ignore joysticks */
 354                 if (test_bit(BTN_TRIGGER, handle->dev->keybit))
 355                         return;
 356
 357                 if (test_bit(BTN_TOOL_FINGER, handle->dev->keybit))
 358                         mousedev_touchpad_event(handle->dev,
 359                                                 mousedev, code, value);
 360                 else
 361                         mousedev_abs_event(handle->dev, mousedev, code, value);
 362
 363                 break;
 364
 365         case EV_REL:
 366                 mousedev_rel_event(mousedev, code, value);
 367                 break;
 368
 369         case EV_KEY:
 370                 if (value != 2) {
 371                         if (code == BTN_TOUCH &&
 372                             test_bit(BTN_TOOL_FINGER, handle->dev->keybit))
 373                                 mousedev_touchpad_touch(mousedev, value);
 374                         else
 375                                 mousedev_key_event(mousedev, code, value);
 376                 }
 377                 break;
 378
 379         case EV_SYN:
 380                 if (code == SYN_REPORT) {
 381                         if (mousedev->touch) {
 382                                 mousedev->pkt_count++;
 383                                 /*
 384                                  * Input system eats duplicate events,
 385                                  * but we need all of them to do correct
 386                                  * averaging so apply present one forward
 387                                  */
 388                                 fx(0) = fx(1);
 389                                 fy(0) = fy(1);
 390                         }
 391
 392                         mousedev_notify_readers(mousedev, &mousedev->packet);
 393                         mousedev_notify_readers(mousedev_mix, &mousedev->packet);
 394
 395                         mousedev->packet.dx = mousedev->packet.dy =
 396                                 mousedev->packet.dz = 0;
 397                         mousedev->packet.abs_event = 0;
 398                 }
 399                 break;
 400         }
 401 }
 402
 403 static int mousedev_fasync(int fd, struct file *file, int on)
 404 {
 405         struct mousedev_client *client = file->private_data;
 406
 407         return fasync_helper(fd, file, on, &client->fasync);
 408 }
 409
 410 static void mousedev_free(struct device *dev)
 411 {
 412         struct mousedev *mousedev = container_of(dev, struct mousedev, dev);
 413
 414         input_put_device(mousedev->handle.dev);
 415         kfree(mousedev);
 416 }
 417
 418 static int mousedev_open_device(struct mousedev *mousedev)
 419 {
 420         int retval;
 421
 422         retval = mutex_lock_interruptible(&mousedev->mutex);
 423         if (retval)
 424                 return retval;
 425
 426         if (mousedev->minor == MOUSEDEV_MIX)
 427                 mixdev_open_devices();
 428         else if (!mousedev->exist)
 429                 retval = -ENODEV;
 430         else if (!mousedev->open++) {
 431                 retval = input_open_device(&mousedev->handle);
 432                 if (retval)
 433                         mousedev->open--;
 434         }
 435
 436         mutex_unlock(&mousedev->mutex);
 437         return retval;
 438 }
 439
 440 static void mousedev_close_device(struct mousedev *mousedev)
 441 {
 442         mutex_lock(&mousedev->mutex);
 443
 444         if (mousedev->minor == MOUSEDEV_MIX)
 445                 mixdev_close_devices();
 446         else if (mousedev->exist && !--mousedev->open)
 447                 input_close_device(&mousedev->handle);
 448
 449         mutex_unlock(&mousedev->mutex);
 450 }
 451
 452 /*
 453  * Open all available devices so they can all be multiplexed in one.
 454  * stream. Note that this function is called with mousedev_mix->mutex
 455  * held.
 456  */
 457 static void mixdev_open_devices(void)
 458 {
 459         struct mousedev *mousedev;
 460
 461         if (mousedev_mix->open++)
 462                 return;
 463
 464         list_for_each_entry(mousedev, &mousedev_mix_list, mixdev_node) {
 465                 if (!mousedev->mixdev_open) {
 466                         if (mousedev_open_device(mousedev))
 467                                 continue;
 468
 469                         mousedev->mixdev_open = 1;
 470                 }
 471         }
 472 }
 473
 474 /*
 475  * Close all devices that were opened as part of multiplexed
 476  * device. Note that this function is called with mousedev_mix->mutex
 477  * held.
 478  */
 479 static void mixdev_close_devices(void)
 480 {
 481         struct mousedev *mousedev;
 482
 483         if (--mousedev_mix->open)
 484                 return;
 485
 486         list_for_each_entry(mousedev, &mousedev_mix_list, mixdev_node) {
 487                 if (mousedev->mixdev_open) {
 488                         mousedev->mixdev_open = 0;
 489                         mousedev_close_device(mousedev);
 490                 }
 491         }
 492 }
 493
 494
 495 static void mousedev_attach_client(struct mousedev *mousedev,
 496                                    struct mousedev_client *client)
 497 {
 498         spin_lock(&mousedev->client_lock);
 499         list_add_tail_rcu(&client->node, &mousedev->client_list);
 500         spin_unlock(&mousedev->client_lock);
 501         synchronize_rcu();
 502 }
 503
 504 static void mousedev_detach_client(struct mousedev *mousedev,
 505                                    struct mousedev_client *client)
 506 {
 507         spin_lock(&mousedev->client_lock);
 508         list_del_rcu(&client->node);
 509         spin_unlock(&mousedev->client_lock);
 510         synchronize_rcu();
 511 }
 512
 513 static int mousedev_release(struct inode *inode, struct file *file)
 514 {
 515         struct mousedev_client *client = file->private_data;
 516         struct mousedev *mousedev = client->mousedev;
 517
 518         mousedev_detach_client(mousedev, client);
 519         kfree(client);
 520
 521         mousedev_close_device(mousedev);
 522         put_device(&mousedev->dev);
 523
 524         return 0;
 525 }
 526
 527 static int mousedev_open(struct inode *inode, struct file *file)
 528 {
 529         struct mousedev_client *client;
 530         struct mousedev *mousedev;
 531         int error;
 532         int i;
 533
 534 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
 535         if (imajor(inode) == MISC_MAJOR)
 536                 i = MOUSEDEV_MIX;
 537         else
 538 #endif
 539                 i = iminor(inode) - MOUSEDEV_MINOR_BASE;
 540
 541         if (i >= MOUSEDEV_MINORS)
 542                 return -ENODEV;
 543
 544         lock_kernel();
 545         error = mutex_lock_interruptible(&mousedev_table_mutex);
 546         if (error) {
 547                 unlock_kernel();
 548                 return error;
 549         }
 550         mousedev = mousedev_table[i];
 551         if (mousedev)
 552                 get_device(&mousedev->dev);
 553         mutex_unlock(&mousedev_table_mutex);
 554
 555         if (!mousedev) {
 556                 unlock_kernel();
 557                 return -ENODEV;
 558         }
 559
 560         client = kzalloc(sizeof(struct mousedev_client), GFP_KERNEL);
 561         if (!client) {
 562                 error = -ENOMEM;
 563                 goto err_put_mousedev;
 564         }
 565
 566         spin_lock_init(&client->packet_lock);
 567         client->pos_x = xres / 2;
 568         client->pos_y = yres / 2;
 569         client->mousedev = mousedev;
 570         mousedev_attach_client(mousedev, client);
 571
 572         error = mousedev_open_device(mousedev);
 573         if (error)
 574                 goto err_free_client;
 575
 576         file->private_data = client;
 577         unlock_kernel();
 578         return 0;
 579
 580  err_free_client:
 581         mousedev_detach_client(mousedev, client);
 582         kfree(client);
 583  err_put_mousedev:
 584         put_device(&mousedev->dev);
 585         unlock_kernel();
 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                 dev_set_name(&mousedev->dev, "mice");
 866         else
 867                 dev_set_name(&mousedev->dev, "mouse%d", minor);
 868
 869         mousedev->minor = minor;
 870         mousedev->exist = 1;
 871         mousedev->handle.dev = input_get_device(dev);
 872         mousedev->handle.name = dev_name(&mousedev->dev);
 873         mousedev->handle.handler = handler;
 874         mousedev->handle.private = mousedev;
 875
 876         mousedev->dev.class = &input_class;
 877         if (dev)
 878                 mousedev->dev.parent = &dev->dev;
 879         mousedev->dev.devt = MKDEV(INPUT_MAJOR, MOUSEDEV_MINOR_BASE + minor);
 880         mousedev->dev.release = mousedev_free;
 881         device_initialize(&mousedev->dev);
 882
 883         if (minor != MOUSEDEV_MIX) {
 884                 error = input_register_handle(&mousedev->handle);
 885                 if (error)
 886                         goto err_free_mousedev;
 887         }
 888
 889         error = mousedev_install_chrdev(mousedev);
 890         if (error)
 891                 goto err_unregister_handle;
 892
 893         error = device_add(&mousedev->dev);
 894         if (error)
 895                 goto err_cleanup_mousedev;
 896
 897         return mousedev;
 898
 899  err_cleanup_mousedev:
 900         mousedev_cleanup(mousedev);
 901  err_unregister_handle:
 902         if (minor != MOUSEDEV_MIX)
 903                 input_unregister_handle(&mousedev->handle);
 904  err_free_mousedev:
 905         put_device(&mousedev->dev);
 906  err_out:
 907         return ERR_PTR(error);
 908 }
 909
 910 static void mousedev_destroy(struct mousedev *mousedev)
 911 {
 912         device_del(&mousedev->dev);
 913         mousedev_cleanup(mousedev);
 914         if (mousedev->minor != MOUSEDEV_MIX)
 915                 input_unregister_handle(&mousedev->handle);
 916         put_device(&mousedev->dev);
 917 }
 918
 919 static int mixdev_add_device(struct mousedev *mousedev)
 920 {
 921         int retval;
 922
 923         retval = mutex_lock_interruptible(&mousedev_mix->mutex);
 924         if (retval)
 925                 return retval;
 926
 927         if (mousedev_mix->open) {
 928                 retval = mousedev_open_device(mousedev);
 929                 if (retval)
 930                         goto out;
 931
 932                 mousedev->mixdev_open = 1;
 933         }
 934
 935         get_device(&mousedev->dev);
 936         list_add_tail(&mousedev->mixdev_node, &mousedev_mix_list);
 937
 938  out:
 939         mutex_unlock(&mousedev_mix->mutex);
 940         return retval;
 941 }
 942
 943 static void mixdev_remove_device(struct mousedev *mousedev)
 944 {
 945         mutex_lock(&mousedev_mix->mutex);
 946
 947         if (mousedev->mixdev_open) {
 948                 mousedev->mixdev_open = 0;
 949                 mousedev_close_device(mousedev);
 950         }
 951
 952         list_del_init(&mousedev->mixdev_node);
 953         mutex_unlock(&mousedev_mix->mutex);
 954
 955         put_device(&mousedev->dev);
 956 }
 957
 958 static int mousedev_connect(struct input_handler *handler,
 959                             struct input_dev *dev,
 960                             const struct input_device_id *id)
 961 {
 962         struct mousedev *mousedev;
 963         int minor;
 964         int error;
 965
 966         for (minor = 0; minor < MOUSEDEV_MINORS; minor++)
 967                 if (!mousedev_table[minor])
 968                         break;
 969
 970         if (minor == MOUSEDEV_MINORS) {
 971                 printk(KERN_ERR "mousedev: no more free mousedev devices\n");
 972                 return -ENFILE;
 973         }
 974
 975         mousedev = mousedev_create(dev, handler, minor);
 976         if (IS_ERR(mousedev))
 977                 return PTR_ERR(mousedev);
 978
 979         error = mixdev_add_device(mousedev);
 980         if (error) {
 981                 mousedev_destroy(mousedev);
 982                 return error;
 983         }
 984
 985         return 0;
 986 }
 987
 988 static void mousedev_disconnect(struct input_handle *handle)
 989 {
 990         struct mousedev *mousedev = handle->private;
 991
 992         mixdev_remove_device(mousedev);
 993         mousedev_destroy(mousedev);
 994 }
 995
 996 static const struct input_device_id mousedev_ids[] = {
 997         {
 998                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 999                                 INPUT_DEVICE_ID_MATCH_KEYBIT |
1000                                 INPUT_DEVICE_ID_MATCH_RELBIT,
1001                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_REL) },
1002                 .keybit = { [BIT_WORD(BTN_LEFT)] = BIT_MASK(BTN_LEFT) },
1003                 .relbit = { BIT_MASK(REL_X) | BIT_MASK(REL_Y) },
1004         },      /* A mouse like device, at least one button,
1005                    two relative axes */
1006         {
1007                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1008                                 INPUT_DEVICE_ID_MATCH_RELBIT,
1009                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_REL) },
1010                 .relbit = { BIT_MASK(REL_WHEEL) },
1011         },      /* A separate scrollwheel */
1012         {
1013                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1014                                 INPUT_DEVICE_ID_MATCH_KEYBIT |
1015                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
1016                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS) },
1017                 .keybit = { [BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH) },
1018                 .absbit = { BIT_MASK(ABS_X) | BIT_MASK(ABS_Y) },
1019         },      /* A tablet like device, at least touch detection,
1020                    two absolute axes */
1021         {
1022                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1023                                 INPUT_DEVICE_ID_MATCH_KEYBIT |
1024                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
1025                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS) },
1026                 .keybit = { [BIT_WORD(BTN_TOOL_FINGER)] =
1027                                 BIT_MASK(BTN_TOOL_FINGER) },
1028                 .absbit = { BIT_MASK(ABS_X) | BIT_MASK(ABS_Y) |
1029                                 BIT_MASK(ABS_PRESSURE) |
1030                                 BIT_MASK(ABS_TOOL_WIDTH) },
1031         },      /* A touchpad */
1032         {
1033                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1034                         INPUT_DEVICE_ID_MATCH_KEYBIT |
1035                         INPUT_DEVICE_ID_MATCH_ABSBIT,
1036                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS) },
1037                 .keybit = { [BIT_WORD(BTN_LEFT)] = BIT_MASK(BTN_LEFT) },
1038                 .absbit = { BIT_MASK(ABS_X) | BIT_MASK(ABS_Y) },
1039         },      /* Mouse-like device with absolute X and Y but ordinary
1040                    clicks, like hp ILO2 High Performance mouse */
1041
1042         { },    /* Terminating entry */
1043 };
1044
1045 MODULE_DEVICE_TABLE(input, mousedev_ids);
1046
1047 static struct input_handler mousedev_handler = {
1048         .event =        mousedev_event,
1049         .connect =      mousedev_connect,
1050         .disconnect =   mousedev_disconnect,
1051         .fops =         &mousedev_fops,
1052         .minor =        MOUSEDEV_MINOR_BASE,
1053         .name =         "mousedev",
1054         .id_table =     mousedev_ids,
1055 };
1056
1057 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
1058 static struct miscdevice psaux_mouse = {
1059         PSMOUSE_MINOR, "psaux", &mousedev_fops
1060 };
1061 static int psaux_registered;
1062 #endif
1063
1064 static int __init mousedev_init(void)
1065 {
1066         int error;
1067
1068         mousedev_mix = mousedev_create(NULL, &mousedev_handler, MOUSEDEV_MIX);
1069         if (IS_ERR(mousedev_mix))
1070                 return PTR_ERR(mousedev_mix);
1071
1072         error = input_register_handler(&mousedev_handler);
1073         if (error) {
1074                 mousedev_destroy(mousedev_mix);
1075                 return error;
1076         }
1077
1078 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
1079         error = misc_register(&psaux_mouse);
1080         if (error)
1081                 printk(KERN_WARNING "mice: could not register psaux device, "
1082                         "error: %d\n", error);
1083         else
1084                 psaux_registered = 1;
1085 #endif
1086
1087         printk(KERN_INFO "mice: PS/2 mouse device common for all mice\n");
1088
1089         return 0;
1090 }
1091
1092 static void __exit mousedev_exit(void)
1093 {
1094 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
1095         if (psaux_registered)
1096                 misc_deregister(&psaux_mouse);
1097 #endif
1098         input_unregister_handler(&mousedev_handler);
1099         mousedev_destroy(mousedev_mix);
1100 }
1101
1102 module_init(mousedev_init);
1103 module_exit(mousedev_exit);