Pileus Git - ~andy/linux/blob - 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 pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  13
  14 #define MOUSEDEV_MINOR_BASE     32
  15 #define MOUSEDEV_MINORS         32
  16 #define MOUSEDEV_MIX            31
  17
  18 #include <linux/sched.h>
  19 #include <linux/slab.h>
  20 #include <linux/poll.h>
  21 #include <linux/module.h>
  22 #include <linux/init.h>
  23 #include <linux/input.h>
  24 #include <linux/random.h>
  25 #include <linux/major.h>
  26 #include <linux/device.h>
  27 #include <linux/kernel.h>
  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 open;
  61         int minor;
  62         struct input_handle handle;
  63         wait_queue_head_t wait;
  64         struct list_head client_list;
  65         spinlock_t client_lock; /* protects client_list */
  66         struct mutex mutex;
  67         struct device dev;
  68         bool exist;
  69
  70         struct list_head mixdev_node;
  71         bool opened_by_mixdev;
  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
 138                 fx(0) = value;
 139                 if (mousedev->touch && mousedev->pkt_count >= 2) {
 140                         size = input_abs_get_max(dev, ABS_X) -
 141                                         input_abs_get_min(dev, ABS_X);
 142                         if (size == 0)
 143                                 size = 256 * 2;
 144
 145                         tmp = ((value - fx(2)) * 256 * FRACTION_DENOM) / size;
 146                         tmp += mousedev->frac_dx;
 147                         mousedev->packet.dx = tmp / FRACTION_DENOM;
 148                         mousedev->frac_dx =
 149                                 tmp - mousedev->packet.dx * FRACTION_DENOM;
 150                 }
 151                 break;
 152
 153         case ABS_Y:
 154                 fy(0) = value;
 155                 if (mousedev->touch && mousedev->pkt_count >= 2) {
 156                         /* use X size for ABS_Y to keep the same scale */
 157                         size = input_abs_get_max(dev, ABS_X) -
 158                                         input_abs_get_min(dev, ABS_X);
 159                         if (size == 0)
 160                                 size = 256 * 2;
 161
 162                         tmp = -((value - fy(2)) * 256 * FRACTION_DENOM) / size;
 163                         tmp += mousedev->frac_dy;
 164                         mousedev->packet.dy = tmp / FRACTION_DENOM;
 165                         mousedev->frac_dy = tmp -
 166                                 mousedev->packet.dy * FRACTION_DENOM;
 167                 }
 168                 break;
 169         }
 170 }
 171
 172 static void mousedev_abs_event(struct input_dev *dev, struct mousedev *mousedev,
 173                                 unsigned int code, int value)
 174 {
 175         int min, max, size;
 176
 177         switch (code) {
 178
 179         case ABS_X:
 180                 min = input_abs_get_min(dev, ABS_X);
 181                 max = input_abs_get_max(dev, ABS_X);
 182
 183                 size = max - min;
 184                 if (size == 0)
 185                         size = xres ? : 1;
 186
 187                 value = clamp(value, min, max);
 188
 189                 mousedev->packet.x = ((value - min) * xres) / size;
 190                 mousedev->packet.abs_event = 1;
 191                 break;
 192
 193         case ABS_Y:
 194                 min = input_abs_get_min(dev, ABS_Y);
 195                 max = input_abs_get_max(dev, ABS_Y);
 196
 197                 size = max - min;
 198                 if (size == 0)
 199                         size = yres ? : 1;
 200
 201                 value = clamp(value, min, max);
 202
 203                 mousedev->packet.y = yres - ((value - min) * yres) / size;
 204                 mousedev->packet.abs_event = 1;
 205                 break;
 206         }
 207 }
 208
 209 static void mousedev_rel_event(struct mousedev *mousedev,
 210                                 unsigned int code, int value)
 211 {
 212         switch (code) {
 213         case REL_X:
 214                 mousedev->packet.dx += value;
 215                 break;
 216
 217         case REL_Y:
 218                 mousedev->packet.dy -= value;
 219                 break;
 220
 221         case REL_WHEEL:
 222                 mousedev->packet.dz -= value;
 223                 break;
 224         }
 225 }
 226
 227 static void mousedev_key_event(struct mousedev *mousedev,
 228                                 unsigned int code, int value)
 229 {
 230         int index;
 231
 232         switch (code) {
 233
 234         case BTN_TOUCH:
 235         case BTN_0:
 236         case BTN_LEFT:          index = 0; break;
 237
 238         case BTN_STYLUS:
 239         case BTN_1:
 240         case BTN_RIGHT:         index = 1; break;
 241
 242         case BTN_2:
 243         case BTN_FORWARD:
 244         case BTN_STYLUS2:
 245         case BTN_MIDDLE:        index = 2; break;
 246
 247         case BTN_3:
 248         case BTN_BACK:
 249         case BTN_SIDE:          index = 3; break;
 250
 251         case BTN_4:
 252         case BTN_EXTRA:         index = 4; break;
 253
 254         default:                return;
 255         }
 256
 257         if (value) {
 258                 set_bit(index, &mousedev->packet.buttons);
 259                 set_bit(index, &mousedev_mix->packet.buttons);
 260         } else {
 261                 clear_bit(index, &mousedev->packet.buttons);
 262                 clear_bit(index, &mousedev_mix->packet.buttons);
 263         }
 264 }
 265
 266 static void mousedev_notify_readers(struct mousedev *mousedev,
 267                                     struct mousedev_hw_data *packet)
 268 {
 269         struct mousedev_client *client;
 270         struct mousedev_motion *p;
 271         unsigned int new_head;
 272         int wake_readers = 0;
 273
 274         rcu_read_lock();
 275         list_for_each_entry_rcu(client, &mousedev->client_list, node) {
 276
 277                 /* Just acquire the lock, interrupts already disabled */
 278                 spin_lock(&client->packet_lock);
 279
 280                 p = &client->packets[client->head];
 281                 if (client->ready && p->buttons != mousedev->packet.buttons) {
 282                         new_head = (client->head + 1) % PACKET_QUEUE_LEN;
 283                         if (new_head != client->tail) {
 284                                 p = &client->packets[client->head = new_head];
 285                                 memset(p, 0, sizeof(struct mousedev_motion));
 286                         }
 287                 }
 288
 289                 if (packet->abs_event) {
 290                         p->dx += packet->x - client->pos_x;
 291                         p->dy += packet->y - client->pos_y;
 292                         client->pos_x = packet->x;
 293                         client->pos_y = packet->y;
 294                 }
 295
 296                 client->pos_x += packet->dx;
 297                 client->pos_x = client->pos_x < 0 ?
 298                         0 : (client->pos_x >= xres ? xres : client->pos_x);
 299                 client->pos_y += packet->dy;
 300                 client->pos_y = client->pos_y < 0 ?
 301                         0 : (client->pos_y >= yres ? yres : client->pos_y);
 302
 303                 p->dx += packet->dx;
 304                 p->dy += packet->dy;
 305                 p->dz += packet->dz;
 306                 p->buttons = mousedev->packet.buttons;
 307
 308                 if (p->dx || p->dy || p->dz ||
 309                     p->buttons != client->last_buttons)
 310                         client->ready = 1;
 311
 312                 spin_unlock(&client->packet_lock);
 313
 314                 if (client->ready) {
 315                         kill_fasync(&client->fasync, SIGIO, POLL_IN);
 316                         wake_readers = 1;
 317                 }
 318         }
 319         rcu_read_unlock();
 320
 321         if (wake_readers)
 322                 wake_up_interruptible(&mousedev->wait);
 323 }
 324
 325 static void mousedev_touchpad_touch(struct mousedev *mousedev, int value)
 326 {
 327         if (!value) {
 328                 if (mousedev->touch &&
 329                     time_before(jiffies,
 330                                 mousedev->touch + msecs_to_jiffies(tap_time))) {
 331                         /*
 332                          * Toggle left button to emulate tap.
 333                          * We rely on the fact that mousedev_mix always has 0
 334                          * motion packet so we won't mess current position.
 335                          */
 336                         set_bit(0, &mousedev->packet.buttons);
 337                         set_bit(0, &mousedev_mix->packet.buttons);
 338                         mousedev_notify_readers(mousedev, &mousedev_mix->packet);
 339                         mousedev_notify_readers(mousedev_mix,
 340                                                 &mousedev_mix->packet);
 341                         clear_bit(0, &mousedev->packet.buttons);
 342                         clear_bit(0, &mousedev_mix->packet.buttons);
 343                 }
 344                 mousedev->touch = mousedev->pkt_count = 0;
 345                 mousedev->frac_dx = 0;
 346                 mousedev->frac_dy = 0;
 347
 348         } else if (!mousedev->touch)
 349                 mousedev->touch = jiffies;
 350 }
 351
 352 static void mousedev_event(struct input_handle *handle,
 353                            unsigned int type, unsigned int code, int value)
 354 {
 355         struct mousedev *mousedev = handle->private;
 356
 357         switch (type) {
 358
 359         case EV_ABS:
 360                 /* Ignore joysticks */
 361                 if (test_bit(BTN_TRIGGER, handle->dev->keybit))
 362                         return;
 363
 364                 if (test_bit(BTN_TOOL_FINGER, handle->dev->keybit))
 365                         mousedev_touchpad_event(handle->dev,
 366                                                 mousedev, code, value);
 367                 else
 368                         mousedev_abs_event(handle->dev, mousedev, code, value);
 369
 370                 break;
 371
 372         case EV_REL:
 373                 mousedev_rel_event(mousedev, code, value);
 374                 break;
 375
 376         case EV_KEY:
 377                 if (value != 2) {
 378                         if (code == BTN_TOUCH &&
 379                             test_bit(BTN_TOOL_FINGER, handle->dev->keybit))
 380                                 mousedev_touchpad_touch(mousedev, value);
 381                         else
 382                                 mousedev_key_event(mousedev, code, value);
 383                 }
 384                 break;
 385
 386         case EV_SYN:
 387                 if (code == SYN_REPORT) {
 388                         if (mousedev->touch) {
 389                                 mousedev->pkt_count++;
 390                                 /*
 391                                  * Input system eats duplicate events,
 392                                  * but we need all of them to do correct
 393                                  * averaging so apply present one forward
 394                                  */
 395                                 fx(0) = fx(1);
 396                                 fy(0) = fy(1);
 397                         }
 398
 399                         mousedev_notify_readers(mousedev, &mousedev->packet);
 400                         mousedev_notify_readers(mousedev_mix, &mousedev->packet);
 401
 402                         mousedev->packet.dx = mousedev->packet.dy =
 403                                 mousedev->packet.dz = 0;
 404                         mousedev->packet.abs_event = 0;
 405                 }
 406                 break;
 407         }
 408 }
 409
 410 static int mousedev_fasync(int fd, struct file *file, int on)
 411 {
 412         struct mousedev_client *client = file->private_data;
 413
 414         return fasync_helper(fd, file, on, &client->fasync);
 415 }
 416
 417 static void mousedev_free(struct device *dev)
 418 {
 419         struct mousedev *mousedev = container_of(dev, struct mousedev, dev);
 420
 421         input_put_device(mousedev->handle.dev);
 422         kfree(mousedev);
 423 }
 424
 425 static int mousedev_open_device(struct mousedev *mousedev)
 426 {
 427         int retval;
 428
 429         retval = mutex_lock_interruptible(&mousedev->mutex);
 430         if (retval)
 431                 return retval;
 432
 433         if (mousedev->minor == MOUSEDEV_MIX)
 434                 mixdev_open_devices();
 435         else if (!mousedev->exist)
 436                 retval = -ENODEV;
 437         else if (!mousedev->open++) {
 438                 retval = input_open_device(&mousedev->handle);
 439                 if (retval)
 440                         mousedev->open--;
 441         }
 442
 443         mutex_unlock(&mousedev->mutex);
 444         return retval;
 445 }
 446
 447 static void mousedev_close_device(struct mousedev *mousedev)
 448 {
 449         mutex_lock(&mousedev->mutex);
 450
 451         if (mousedev->minor == MOUSEDEV_MIX)
 452                 mixdev_close_devices();
 453         else if (mousedev->exist && !--mousedev->open)
 454                 input_close_device(&mousedev->handle);
 455
 456         mutex_unlock(&mousedev->mutex);
 457 }
 458
 459 /*
 460  * Open all available devices so they can all be multiplexed in one.
 461  * stream. Note that this function is called with mousedev_mix->mutex
 462  * held.
 463  */
 464 static void mixdev_open_devices(void)
 465 {
 466         struct mousedev *mousedev;
 467
 468         if (mousedev_mix->open++)
 469                 return;
 470
 471         list_for_each_entry(mousedev, &mousedev_mix_list, mixdev_node) {
 472                 if (!mousedev->opened_by_mixdev) {
 473                         if (mousedev_open_device(mousedev))
 474                                 continue;
 475
 476                         mousedev->opened_by_mixdev = true;
 477                 }
 478         }
 479 }
 480
 481 /*
 482  * Close all devices that were opened as part of multiplexed
 483  * device. Note that this function is called with mousedev_mix->mutex
 484  * held.
 485  */
 486 static void mixdev_close_devices(void)
 487 {
 488         struct mousedev *mousedev;
 489
 490         if (--mousedev_mix->open)
 491                 return;
 492
 493         list_for_each_entry(mousedev, &mousedev_mix_list, mixdev_node) {
 494                 if (mousedev->opened_by_mixdev) {
 495                         mousedev->opened_by_mixdev = false;
 496                         mousedev_close_device(mousedev);
 497                 }
 498         }
 499 }
 500
 501
 502 static void mousedev_attach_client(struct mousedev *mousedev,
 503                                    struct mousedev_client *client)
 504 {
 505         spin_lock(&mousedev->client_lock);
 506         list_add_tail_rcu(&client->node, &mousedev->client_list);
 507         spin_unlock(&mousedev->client_lock);
 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_rcu();
 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_detach_client(mousedev, client);
 525         kfree(client);
 526
 527         mousedev_close_device(mousedev);
 528         put_device(&mousedev->dev);
 529
 530         return 0;
 531 }
 532
 533 static int mousedev_open(struct inode *inode, struct file *file)
 534 {
 535         struct mousedev_client *client;
 536         struct mousedev *mousedev;
 537         int error;
 538         int i;
 539
 540 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
 541         if (imajor(inode) == MISC_MAJOR)
 542                 i = MOUSEDEV_MIX;
 543         else
 544 #endif
 545                 i = iminor(inode) - MOUSEDEV_MINOR_BASE;
 546
 547         if (i >= MOUSEDEV_MINORS)
 548                 return -ENODEV;
 549
 550         error = mutex_lock_interruptible(&mousedev_table_mutex);
 551         if (error)
 552                 return error;
 553
 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         nonseekable_open(inode, file);
 580         return 0;
 581
 582  err_free_client:
 583         mousedev_detach_client(mousedev, client);
 584         kfree(client);
 585  err_put_mousedev:
 586         put_device(&mousedev->dev);
 587         return error;
 588 }
 589
 590 static inline int mousedev_limit_delta(int delta, int limit)
 591 {
 592         return delta > limit ? limit : (delta < -limit ? -limit : delta);
 593 }
 594
 595 static void mousedev_packet(struct mousedev_client *client,
 596                             signed char *ps2_data)
 597 {
 598         struct mousedev_motion *p = &client->packets[client->tail];
 599
 600         ps2_data[0] = 0x08 |
 601                 ((p->dx < 0) << 4) | ((p->dy < 0) << 5) | (p->buttons & 0x07);
 602         ps2_data[1] = mousedev_limit_delta(p->dx, 127);
 603         ps2_data[2] = mousedev_limit_delta(p->dy, 127);
 604         p->dx -= ps2_data[1];
 605         p->dy -= ps2_data[2];
 606
 607         switch (client->mode) {
 608         case MOUSEDEV_EMUL_EXPS:
 609                 ps2_data[3] = mousedev_limit_delta(p->dz, 7);
 610                 p->dz -= ps2_data[3];
 611                 ps2_data[3] = (ps2_data[3] & 0x0f) | ((p->buttons & 0x18) << 1);
 612                 client->bufsiz = 4;
 613                 break;
 614
 615         case MOUSEDEV_EMUL_IMPS:
 616                 ps2_data[0] |=
 617                         ((p->buttons & 0x10) >> 3) | ((p->buttons & 0x08) >> 1);
 618                 ps2_data[3] = mousedev_limit_delta(p->dz, 127);
 619                 p->dz -= ps2_data[3];
 620                 client->bufsiz = 4;
 621                 break;
 622
 623         case MOUSEDEV_EMUL_PS2:
 624         default:
 625                 ps2_data[0] |=
 626                         ((p->buttons & 0x10) >> 3) | ((p->buttons & 0x08) >> 1);
 627                 p->dz = 0;
 628                 client->bufsiz = 3;
 629                 break;
 630         }
 631
 632         if (!p->dx && !p->dy && !p->dz) {
 633                 if (client->tail == client->head) {
 634                         client->ready = 0;
 635                         client->last_buttons = p->buttons;
 636                 } else
 637                         client->tail = (client->tail + 1) % PACKET_QUEUE_LEN;
 638         }
 639 }
 640
 641 static void mousedev_generate_response(struct mousedev_client *client,
 642                                         int command)
 643 {
 644         client->ps2[0] = 0xfa; /* ACK */
 645
 646         switch (command) {
 647
 648         case 0xeb: /* Poll */
 649                 mousedev_packet(client, &client->ps2[1]);
 650                 client->bufsiz++; /* account for leading ACK */
 651                 break;
 652
 653         case 0xf2: /* Get ID */
 654                 switch (client->mode) {
 655                 case MOUSEDEV_EMUL_PS2:
 656                         client->ps2[1] = 0;
 657                         break;
 658                 case MOUSEDEV_EMUL_IMPS:
 659                         client->ps2[1] = 3;
 660                         break;
 661                 case MOUSEDEV_EMUL_EXPS:
 662                         client->ps2[1] = 4;
 663                         break;
 664                 }
 665                 client->bufsiz = 2;
 666                 break;
 667
 668         case 0xe9: /* Get info */
 669                 client->ps2[1] = 0x60; client->ps2[2] = 3; client->ps2[3] = 200;
 670                 client->bufsiz = 4;
 671                 break;
 672
 673         case 0xff: /* Reset */
 674                 client->impsseq = client->imexseq = 0;
 675                 client->mode = MOUSEDEV_EMUL_PS2;
 676                 client->ps2[1] = 0xaa; client->ps2[2] = 0x00;
 677                 client->bufsiz = 3;
 678                 break;
 679
 680         default:
 681                 client->bufsiz = 1;
 682                 break;
 683         }
 684         client->buffer = client->bufsiz;
 685 }
 686
 687 static ssize_t mousedev_write(struct file *file, const char __user *buffer,
 688                                 size_t count, loff_t *ppos)
 689 {
 690         struct mousedev_client *client = file->private_data;
 691         unsigned char c;
 692         unsigned int i;
 693
 694         for (i = 0; i < count; i++) {
 695
 696                 if (get_user(c, buffer + i))
 697                         return -EFAULT;
 698
 699                 spin_lock_irq(&client->packet_lock);
 700
 701                 if (c == mousedev_imex_seq[client->imexseq]) {
 702                         if (++client->imexseq == MOUSEDEV_SEQ_LEN) {
 703                                 client->imexseq = 0;
 704                                 client->mode = MOUSEDEV_EMUL_EXPS;
 705                         }
 706                 } else
 707                         client->imexseq = 0;
 708
 709                 if (c == mousedev_imps_seq[client->impsseq]) {
 710                         if (++client->impsseq == MOUSEDEV_SEQ_LEN) {
 711                                 client->impsseq = 0;
 712                                 client->mode = MOUSEDEV_EMUL_IMPS;
 713                         }
 714                 } else
 715                         client->impsseq = 0;
 716
 717                 mousedev_generate_response(client, c);
 718
 719                 spin_unlock_irq(&client->packet_lock);
 720         }
 721
 722         kill_fasync(&client->fasync, SIGIO, POLL_IN);
 723         wake_up_interruptible(&client->mousedev->wait);
 724
 725         return count;
 726 }
 727
 728 static ssize_t mousedev_read(struct file *file, char __user *buffer,
 729                              size_t count, loff_t *ppos)
 730 {
 731         struct mousedev_client *client = file->private_data;
 732         struct mousedev *mousedev = client->mousedev;
 733         signed char data[sizeof(client->ps2)];
 734         int retval = 0;
 735
 736         if (!client->ready && !client->buffer && mousedev->exist &&
 737             (file->f_flags & O_NONBLOCK))
 738                 return -EAGAIN;
 739
 740         retval = wait_event_interruptible(mousedev->wait,
 741                         !mousedev->exist || client->ready || client->buffer);
 742         if (retval)
 743                 return retval;
 744
 745         if (!mousedev->exist)
 746                 return -ENODEV;
 747
 748         spin_lock_irq(&client->packet_lock);
 749
 750         if (!client->buffer && client->ready) {
 751                 mousedev_packet(client, client->ps2);
 752                 client->buffer = client->bufsiz;
 753         }
 754
 755         if (count > client->buffer)
 756                 count = client->buffer;
 757
 758         memcpy(data, client->ps2 + client->bufsiz - client->buffer, count);
 759         client->buffer -= count;
 760
 761         spin_unlock_irq(&client->packet_lock);
 762
 763         if (copy_to_user(buffer, data, count))
 764                 return -EFAULT;
 765
 766         return count;
 767 }
 768
 769 /* No kernel lock - fine */
 770 static unsigned int mousedev_poll(struct file *file, poll_table *wait)
 771 {
 772         struct mousedev_client *client = file->private_data;
 773         struct mousedev *mousedev = client->mousedev;
 774         unsigned int mask;
 775
 776         poll_wait(file, &mousedev->wait, wait);
 777
 778         mask = mousedev->exist ? POLLOUT | POLLWRNORM : POLLHUP | POLLERR;
 779         if (client->ready || client->buffer)
 780                 mask |= POLLIN | POLLRDNORM;
 781
 782         return mask;
 783 }
 784
 785 static const struct file_operations mousedev_fops = {
 786         .owner          = THIS_MODULE,
 787         .read           = mousedev_read,
 788         .write          = mousedev_write,
 789         .poll           = mousedev_poll,
 790         .open           = mousedev_open,
 791         .release        = mousedev_release,
 792         .fasync         = mousedev_fasync,
 793         .llseek         = noop_llseek,
 794 };
 795
 796 static int mousedev_install_chrdev(struct mousedev *mousedev)
 797 {
 798         mousedev_table[mousedev->minor] = mousedev;
 799         return 0;
 800 }
 801
 802 static void mousedev_remove_chrdev(struct mousedev *mousedev)
 803 {
 804         mutex_lock(&mousedev_table_mutex);
 805         mousedev_table[mousedev->minor] = NULL;
 806         mutex_unlock(&mousedev_table_mutex);
 807 }
 808
 809 /*
 810  * Mark device non-existent. This disables writes, ioctls and
 811  * prevents new users from opening the device. Already posted
 812  * blocking reads will stay, however new ones will fail.
 813  */
 814 static void mousedev_mark_dead(struct mousedev *mousedev)
 815 {
 816         mutex_lock(&mousedev->mutex);
 817         mousedev->exist = false;
 818         mutex_unlock(&mousedev->mutex);
 819 }
 820
 821 /*
 822  * Wake up users waiting for IO so they can disconnect from
 823  * dead device.
 824  */
 825 static void mousedev_hangup(struct mousedev *mousedev)
 826 {
 827         struct mousedev_client *client;
 828
 829         spin_lock(&mousedev->client_lock);
 830         list_for_each_entry(client, &mousedev->client_list, node)
 831                 kill_fasync(&client->fasync, SIGIO, POLL_HUP);
 832         spin_unlock(&mousedev->client_lock);
 833
 834         wake_up_interruptible(&mousedev->wait);
 835 }
 836
 837 static void mousedev_cleanup(struct mousedev *mousedev)
 838 {
 839         struct input_handle *handle = &mousedev->handle;
 840
 841         mousedev_mark_dead(mousedev);
 842         mousedev_hangup(mousedev);
 843         mousedev_remove_chrdev(mousedev);
 844
 845         /* mousedev is marked dead so no one else accesses mousedev->open */
 846         if (mousedev->open)
 847                 input_close_device(handle);
 848 }
 849
 850 static struct mousedev *mousedev_create(struct input_dev *dev,
 851                                         struct input_handler *handler,
 852                                         int minor)
 853 {
 854         struct mousedev *mousedev;
 855         int error;
 856
 857         mousedev = kzalloc(sizeof(struct mousedev), GFP_KERNEL);
 858         if (!mousedev) {
 859                 error = -ENOMEM;
 860                 goto err_out;
 861         }
 862
 863         INIT_LIST_HEAD(&mousedev->client_list);
 864         INIT_LIST_HEAD(&mousedev->mixdev_node);
 865         spin_lock_init(&mousedev->client_lock);
 866         mutex_init(&mousedev->mutex);
 867         lockdep_set_subclass(&mousedev->mutex,
 868                              minor == MOUSEDEV_MIX ? SINGLE_DEPTH_NESTING : 0);
 869         init_waitqueue_head(&mousedev->wait);
 870
 871         if (minor == MOUSEDEV_MIX)
 872                 dev_set_name(&mousedev->dev, "mice");
 873         else
 874                 dev_set_name(&mousedev->dev, "mouse%d", minor);
 875
 876         mousedev->minor = minor;
 877         mousedev->exist = true;
 878         mousedev->handle.dev = input_get_device(dev);
 879         mousedev->handle.name = dev_name(&mousedev->dev);
 880         mousedev->handle.handler = handler;
 881         mousedev->handle.private = mousedev;
 882
 883         mousedev->dev.class = &input_class;
 884         if (dev)
 885                 mousedev->dev.parent = &dev->dev;
 886         mousedev->dev.devt = MKDEV(INPUT_MAJOR, MOUSEDEV_MINOR_BASE + minor);
 887         mousedev->dev.release = mousedev_free;
 888         device_initialize(&mousedev->dev);
 889
 890         if (minor != MOUSEDEV_MIX) {
 891                 error = input_register_handle(&mousedev->handle);
 892                 if (error)
 893                         goto err_free_mousedev;
 894         }
 895
 896         error = mousedev_install_chrdev(mousedev);
 897         if (error)
 898                 goto err_unregister_handle;
 899
 900         error = device_add(&mousedev->dev);
 901         if (error)
 902                 goto err_cleanup_mousedev;
 903
 904         return mousedev;
 905
 906  err_cleanup_mousedev:
 907         mousedev_cleanup(mousedev);
 908  err_unregister_handle:
 909         if (minor != MOUSEDEV_MIX)
 910                 input_unregister_handle(&mousedev->handle);
 911  err_free_mousedev:
 912         put_device(&mousedev->dev);
 913  err_out:
 914         return ERR_PTR(error);
 915 }
 916
 917 static void mousedev_destroy(struct mousedev *mousedev)
 918 {
 919         device_del(&mousedev->dev);
 920         mousedev_cleanup(mousedev);
 921         if (mousedev->minor != MOUSEDEV_MIX)
 922                 input_unregister_handle(&mousedev->handle);
 923         put_device(&mousedev->dev);
 924 }
 925
 926 static int mixdev_add_device(struct mousedev *mousedev)
 927 {
 928         int retval;
 929
 930         retval = mutex_lock_interruptible(&mousedev_mix->mutex);
 931         if (retval)
 932                 return retval;
 933
 934         if (mousedev_mix->open) {
 935                 retval = mousedev_open_device(mousedev);
 936                 if (retval)
 937                         goto out;
 938
 939                 mousedev->opened_by_mixdev = true;
 940         }
 941
 942         get_device(&mousedev->dev);
 943         list_add_tail(&mousedev->mixdev_node, &mousedev_mix_list);
 944
 945  out:
 946         mutex_unlock(&mousedev_mix->mutex);
 947         return retval;
 948 }
 949
 950 static void mixdev_remove_device(struct mousedev *mousedev)
 951 {
 952         mutex_lock(&mousedev_mix->mutex);
 953
 954         if (mousedev->opened_by_mixdev) {
 955                 mousedev->opened_by_mixdev = false;
 956                 mousedev_close_device(mousedev);
 957         }
 958
 959         list_del_init(&mousedev->mixdev_node);
 960         mutex_unlock(&mousedev_mix->mutex);
 961
 962         put_device(&mousedev->dev);
 963 }
 964
 965 static int mousedev_connect(struct input_handler *handler,
 966                             struct input_dev *dev,
 967                             const struct input_device_id *id)
 968 {
 969         struct mousedev *mousedev;
 970         int minor;
 971         int error;
 972
 973         for (minor = 0; minor < MOUSEDEV_MINORS; minor++)
 974                 if (!mousedev_table[minor])
 975                         break;
 976
 977         if (minor == MOUSEDEV_MINORS) {
 978                 pr_err("no more free mousedev devices\n");
 979                 return -ENFILE;
 980         }
 981
 982         mousedev = mousedev_create(dev, handler, minor);
 983         if (IS_ERR(mousedev))
 984                 return PTR_ERR(mousedev);
 985
 986         error = mixdev_add_device(mousedev);
 987         if (error) {
 988                 mousedev_destroy(mousedev);
 989                 return error;
 990         }
 991
 992         return 0;
 993 }
 994
 995 static void mousedev_disconnect(struct input_handle *handle)
 996 {
 997         struct mousedev *mousedev = handle->private;
 998
 999         mixdev_remove_device(mousedev);
1000         mousedev_destroy(mousedev);
1001 }
1002
1003 static const struct input_device_id mousedev_ids[] = {
1004         {
1005                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1006                                 INPUT_DEVICE_ID_MATCH_KEYBIT |
1007                                 INPUT_DEVICE_ID_MATCH_RELBIT,
1008                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_REL) },
1009                 .keybit = { [BIT_WORD(BTN_LEFT)] = BIT_MASK(BTN_LEFT) },
1010                 .relbit = { BIT_MASK(REL_X) | BIT_MASK(REL_Y) },
1011         },      /* A mouse like device, at least one button,
1012                    two relative axes */
1013         {
1014                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1015                                 INPUT_DEVICE_ID_MATCH_RELBIT,
1016                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_REL) },
1017                 .relbit = { BIT_MASK(REL_WHEEL) },
1018         },      /* A separate scrollwheel */
1019         {
1020                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1021                                 INPUT_DEVICE_ID_MATCH_KEYBIT |
1022                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
1023                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS) },
1024                 .keybit = { [BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH) },
1025                 .absbit = { BIT_MASK(ABS_X) | BIT_MASK(ABS_Y) },
1026         },      /* A tablet like device, at least touch detection,
1027                    two absolute axes */
1028         {
1029                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1030                                 INPUT_DEVICE_ID_MATCH_KEYBIT |
1031                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
1032                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS) },
1033                 .keybit = { [BIT_WORD(BTN_TOOL_FINGER)] =
1034                                 BIT_MASK(BTN_TOOL_FINGER) },
1035                 .absbit = { BIT_MASK(ABS_X) | BIT_MASK(ABS_Y) |
1036                                 BIT_MASK(ABS_PRESSURE) |
1037                                 BIT_MASK(ABS_TOOL_WIDTH) },
1038         },      /* A touchpad */
1039         {
1040                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1041                         INPUT_DEVICE_ID_MATCH_KEYBIT |
1042                         INPUT_DEVICE_ID_MATCH_ABSBIT,
1043                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS) },
1044                 .keybit = { [BIT_WORD(BTN_LEFT)] = BIT_MASK(BTN_LEFT) },
1045                 .absbit = { BIT_MASK(ABS_X) | BIT_MASK(ABS_Y) },
1046         },      /* Mouse-like device with absolute X and Y but ordinary
1047                    clicks, like hp ILO2 High Performance mouse */
1048
1049         { },    /* Terminating entry */
1050 };
1051
1052 MODULE_DEVICE_TABLE(input, mousedev_ids);
1053
1054 static struct input_handler mousedev_handler = {
1055         .event          = mousedev_event,
1056         .connect        = mousedev_connect,
1057         .disconnect     = mousedev_disconnect,
1058         .fops           = &mousedev_fops,
1059         .minor          = MOUSEDEV_MINOR_BASE,
1060         .name           = "mousedev",
1061         .id_table       = mousedev_ids,
1062 };
1063
1064 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
1065 #include <linux/miscdevice.h>
1066
1067 static struct miscdevice psaux_mouse = {
1068         .minor  = PSMOUSE_MINOR,
1069         .name   = "psaux",
1070         .fops   = &mousedev_fops,
1071 };
1072
1073 static bool psaux_registered;
1074
1075 static void __init mousedev_psaux_register(void)
1076 {
1077         int error;
1078
1079         error = misc_register(&psaux_mouse);
1080         if (error)
1081                 pr_warn("could not register psaux device, error: %d\n",
1082                            error);
1083         else
1084                 psaux_registered = true;
1085 }
1086
1087 static void __exit mousedev_psaux_unregister(void)
1088 {
1089         if (psaux_registered)
1090                 misc_deregister(&psaux_mouse);
1091 }
1092 #else
1093 static inline void mousedev_psaux_register(void) { }
1094 static inline void mousedev_psaux_unregister(void) { }
1095 #endif
1096
1097 static int __init mousedev_init(void)
1098 {
1099         int error;
1100
1101         mousedev_mix = mousedev_create(NULL, &mousedev_handler, MOUSEDEV_MIX);
1102         if (IS_ERR(mousedev_mix))
1103                 return PTR_ERR(mousedev_mix);
1104
1105         error = input_register_handler(&mousedev_handler);
1106         if (error) {
1107                 mousedev_destroy(mousedev_mix);
1108                 return error;
1109         }
1110
1111         mousedev_psaux_register();
1112
1113         pr_info("PS/2 mouse device common for all mice\n");
1114
1115         return 0;
1116 }
1117
1118 static void __exit mousedev_exit(void)
1119 {
1120         mousedev_psaux_unregister();
1121         input_unregister_handler(&mousedev_handler);
1122         mousedev_destroy(mousedev_mix);
1123 }
1124
1125 module_init(mousedev_init);
1126 module_exit(mousedev_exit);