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         31
  16 #define MOUSEDEV_MIX            63
  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/cdev.h>
  28 #include <linux/kernel.h>
  29
  30 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
  31 MODULE_DESCRIPTION("Mouse (ExplorerPS/2) device interfaces");
  32 MODULE_LICENSE("GPL");
  33
  34 #ifndef CONFIG_INPUT_MOUSEDEV_SCREEN_X
  35 #define CONFIG_INPUT_MOUSEDEV_SCREEN_X  1024
  36 #endif
  37 #ifndef CONFIG_INPUT_MOUSEDEV_SCREEN_Y
  38 #define CONFIG_INPUT_MOUSEDEV_SCREEN_Y  768
  39 #endif
  40
  41 static int xres = CONFIG_INPUT_MOUSEDEV_SCREEN_X;
  42 module_param(xres, uint, 0644);
  43 MODULE_PARM_DESC(xres, "Horizontal screen resolution");
  44
  45 static int yres = CONFIG_INPUT_MOUSEDEV_SCREEN_Y;
  46 module_param(yres, uint, 0644);
  47 MODULE_PARM_DESC(yres, "Vertical screen resolution");
  48
  49 static unsigned tap_time = 200;
  50 module_param(tap_time, uint, 0644);
  51 MODULE_PARM_DESC(tap_time, "Tap time for touchpads in absolute mode (msecs)");
  52
  53 struct mousedev_hw_data {
  54         int dx, dy, dz;
  55         int x, y;
  56         int abs_event;
  57         unsigned long buttons;
  58 };
  59
  60 struct mousedev {
  61         int open;
  62         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         struct cdev cdev;
  69         bool exist;
  70
  71         struct list_head mixdev_node;
  72         bool opened_by_mixdev;
  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         int (*open_device)(struct mousedev *mousedev);
  81         void (*close_device)(struct mousedev *mousedev);
  82 };
  83
  84 enum mousedev_emul {
  85         MOUSEDEV_EMUL_PS2,
  86         MOUSEDEV_EMUL_IMPS,
  87         MOUSEDEV_EMUL_EXPS
  88 };
  89
  90 struct mousedev_motion {
  91         int dx, dy, dz;
  92         unsigned long buttons;
  93 };
  94
  95 #define PACKET_QUEUE_LEN        16
  96 struct mousedev_client {
  97         struct fasync_struct *fasync;
  98         struct mousedev *mousedev;
  99         struct list_head node;
 100
 101         struct mousedev_motion packets[PACKET_QUEUE_LEN];
 102         unsigned int head, tail;
 103         spinlock_t packet_lock;
 104         int pos_x, pos_y;
 105
 106         signed char ps2[6];
 107         unsigned char ready, buffer, bufsiz;
 108         unsigned char imexseq, impsseq;
 109         enum mousedev_emul mode;
 110         unsigned long last_buttons;
 111 };
 112
 113 #define MOUSEDEV_SEQ_LEN        6
 114
 115 static unsigned char mousedev_imps_seq[] = { 0xf3, 200, 0xf3, 100, 0xf3, 80 };
 116 static unsigned char mousedev_imex_seq[] = { 0xf3, 200, 0xf3, 200, 0xf3, 80 };
 117
 118 static struct mousedev *mousedev_mix;
 119 static LIST_HEAD(mousedev_mix_list);
 120
 121 #define fx(i)  (mousedev->old_x[(mousedev->pkt_count - (i)) & 03])
 122 #define fy(i)  (mousedev->old_y[(mousedev->pkt_count - (i)) & 03])
 123
 124 static void mousedev_touchpad_event(struct input_dev *dev,
 125                                     struct mousedev *mousedev,
 126                                     unsigned int code, int value)
 127 {
 128         int size, tmp;
 129         enum { FRACTION_DENOM = 128 };
 130
 131         switch (code) {
 132
 133         case ABS_X:
 134
 135                 fx(0) = value;
 136                 if (mousedev->touch && mousedev->pkt_count >= 2) {
 137                         size = input_abs_get_max(dev, ABS_X) -
 138                                         input_abs_get_min(dev, ABS_X);
 139                         if (size == 0)
 140                                 size = 256 * 2;
 141
 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 for ABS_Y to keep the same scale */
 154                         size = input_abs_get_max(dev, ABS_X) -
 155                                         input_abs_get_min(dev, ABS_X);
 156                         if (size == 0)
 157                                 size = 256 * 2;
 158
 159                         tmp = -((value - fy(2)) * 256 * FRACTION_DENOM) / size;
 160                         tmp += mousedev->frac_dy;
 161                         mousedev->packet.dy = tmp / FRACTION_DENOM;
 162                         mousedev->frac_dy = tmp -
 163                                 mousedev->packet.dy * FRACTION_DENOM;
 164                 }
 165                 break;
 166         }
 167 }
 168
 169 static void mousedev_abs_event(struct input_dev *dev, struct mousedev *mousedev,
 170                                 unsigned int code, int value)
 171 {
 172         int min, max, size;
 173
 174         switch (code) {
 175
 176         case ABS_X:
 177                 min = input_abs_get_min(dev, ABS_X);
 178                 max = input_abs_get_max(dev, ABS_X);
 179
 180                 size = max - min;
 181                 if (size == 0)
 182                         size = xres ? : 1;
 183
 184                 value = clamp(value, min, max);
 185
 186                 mousedev->packet.x = ((value - min) * xres) / size;
 187                 mousedev->packet.abs_event = 1;
 188                 break;
 189
 190         case ABS_Y:
 191                 min = input_abs_get_min(dev, ABS_Y);
 192                 max = input_abs_get_max(dev, ABS_Y);
 193
 194                 size = max - min;
 195                 if (size == 0)
 196                         size = yres ? : 1;
 197
 198                 value = clamp(value, min, max);
 199
 200                 mousedev->packet.y = yres - ((value - min) * yres) / size;
 201                 mousedev->packet.abs_event = 1;
 202                 break;
 203         }
 204 }
 205
 206 static void mousedev_rel_event(struct mousedev *mousedev,
 207                                 unsigned int code, int value)
 208 {
 209         switch (code) {
 210         case REL_X:
 211                 mousedev->packet.dx += value;
 212                 break;
 213
 214         case REL_Y:
 215                 mousedev->packet.dy -= value;
 216                 break;
 217
 218         case REL_WHEEL:
 219                 mousedev->packet.dz -= value;
 220                 break;
 221         }
 222 }
 223
 224 static void mousedev_key_event(struct mousedev *mousedev,
 225                                 unsigned int code, int value)
 226 {
 227         int index;
 228
 229         switch (code) {
 230
 231         case BTN_TOUCH:
 232         case BTN_0:
 233         case BTN_LEFT:          index = 0; break;
 234
 235         case BTN_STYLUS:
 236         case BTN_1:
 237         case BTN_RIGHT:         index = 1; break;
 238
 239         case BTN_2:
 240         case BTN_FORWARD:
 241         case BTN_STYLUS2:
 242         case BTN_MIDDLE:        index = 2; break;
 243
 244         case BTN_3:
 245         case BTN_BACK:
 246         case BTN_SIDE:          index = 3; break;
 247
 248         case BTN_4:
 249         case BTN_EXTRA:         index = 4; break;
 250
 251         default:                return;
 252         }
 253
 254         if (value) {
 255                 set_bit(index, &mousedev->packet.buttons);
 256                 set_bit(index, &mousedev_mix->packet.buttons);
 257         } else {
 258                 clear_bit(index, &mousedev->packet.buttons);
 259                 clear_bit(index, &mousedev_mix->packet.buttons);
 260         }
 261 }
 262
 263 static void mousedev_notify_readers(struct mousedev *mousedev,
 264                                     struct mousedev_hw_data *packet)
 265 {
 266         struct mousedev_client *client;
 267         struct mousedev_motion *p;
 268         unsigned int new_head;
 269         int wake_readers = 0;
 270
 271         rcu_read_lock();
 272         list_for_each_entry_rcu(client, &mousedev->client_list, node) {
 273
 274                 /* Just acquire the lock, interrupts already disabled */
 275                 spin_lock(&client->packet_lock);
 276
 277                 p = &client->packets[client->head];
 278                 if (client->ready && p->buttons != mousedev->packet.buttons) {
 279                         new_head = (client->head + 1) % PACKET_QUEUE_LEN;
 280                         if (new_head != client->tail) {
 281                                 p = &client->packets[client->head = new_head];
 282                                 memset(p, 0, sizeof(struct mousedev_motion));
 283                         }
 284                 }
 285
 286                 if (packet->abs_event) {
 287                         p->dx += packet->x - client->pos_x;
 288                         p->dy += packet->y - client->pos_y;
 289                         client->pos_x = packet->x;
 290                         client->pos_y = packet->y;
 291                 }
 292
 293                 client->pos_x += packet->dx;
 294                 client->pos_x = client->pos_x < 0 ?
 295                         0 : (client->pos_x >= xres ? xres : client->pos_x);
 296                 client->pos_y += packet->dy;
 297                 client->pos_y = client->pos_y < 0 ?
 298                         0 : (client->pos_y >= yres ? yres : client->pos_y);
 299
 300                 p->dx += packet->dx;
 301                 p->dy += packet->dy;
 302                 p->dz += packet->dz;
 303                 p->buttons = mousedev->packet.buttons;
 304
 305                 if (p->dx || p->dy || p->dz ||
 306                     p->buttons != client->last_buttons)
 307                         client->ready = 1;
 308
 309                 spin_unlock(&client->packet_lock);
 310
 311                 if (client->ready) {
 312                         kill_fasync(&client->fasync, SIGIO, POLL_IN);
 313                         wake_readers = 1;
 314                 }
 315         }
 316         rcu_read_unlock();
 317
 318         if (wake_readers)
 319                 wake_up_interruptible(&mousedev->wait);
 320 }
 321
 322 static void mousedev_touchpad_touch(struct mousedev *mousedev, int value)
 323 {
 324         if (!value) {
 325                 if (mousedev->touch &&
 326                     time_before(jiffies,
 327                                 mousedev->touch + msecs_to_jiffies(tap_time))) {
 328                         /*
 329                          * Toggle left button to emulate tap.
 330                          * We rely on the fact that mousedev_mix always has 0
 331                          * motion packet so we won't mess current position.
 332                          */
 333                         set_bit(0, &mousedev->packet.buttons);
 334                         set_bit(0, &mousedev_mix->packet.buttons);
 335                         mousedev_notify_readers(mousedev, &mousedev_mix->packet);
 336                         mousedev_notify_readers(mousedev_mix,
 337                                                 &mousedev_mix->packet);
 338                         clear_bit(0, &mousedev->packet.buttons);
 339                         clear_bit(0, &mousedev_mix->packet.buttons);
 340                 }
 341                 mousedev->touch = mousedev->pkt_count = 0;
 342                 mousedev->frac_dx = 0;
 343                 mousedev->frac_dy = 0;
 344
 345         } else if (!mousedev->touch)
 346                 mousedev->touch = jiffies;
 347 }
 348
 349 static void mousedev_event(struct input_handle *handle,
 350                            unsigned int type, unsigned int code, int value)
 351 {
 352         struct mousedev *mousedev = handle->private;
 353
 354         switch (type) {
 355
 356         case EV_ABS:
 357                 /* Ignore joysticks */
 358                 if (test_bit(BTN_TRIGGER, handle->dev->keybit))
 359                         return;
 360
 361                 if (test_bit(BTN_TOOL_FINGER, handle->dev->keybit))
 362                         mousedev_touchpad_event(handle->dev,
 363                                                 mousedev, code, value);
 364                 else
 365                         mousedev_abs_event(handle->dev, mousedev, code, value);
 366
 367                 break;
 368
 369         case EV_REL:
 370                 mousedev_rel_event(mousedev, code, value);
 371                 break;
 372
 373         case EV_KEY:
 374                 if (value != 2) {
 375                         if (code == BTN_TOUCH &&
 376                             test_bit(BTN_TOOL_FINGER, handle->dev->keybit))
 377                                 mousedev_touchpad_touch(mousedev, value);
 378                         else
 379                                 mousedev_key_event(mousedev, code, value);
 380                 }
 381                 break;
 382
 383         case EV_SYN:
 384                 if (code == SYN_REPORT) {
 385                         if (mousedev->touch) {
 386                                 mousedev->pkt_count++;
 387                                 /*
 388                                  * Input system eats duplicate events,
 389                                  * but we need all of them to do correct
 390                                  * averaging so apply present one forward
 391                                  */
 392                                 fx(0) = fx(1);
 393                                 fy(0) = fy(1);
 394                         }
 395
 396                         mousedev_notify_readers(mousedev, &mousedev->packet);
 397                         mousedev_notify_readers(mousedev_mix, &mousedev->packet);
 398
 399                         mousedev->packet.dx = mousedev->packet.dy =
 400                                 mousedev->packet.dz = 0;
 401                         mousedev->packet.abs_event = 0;
 402                 }
 403                 break;
 404         }
 405 }
 406
 407 static int mousedev_fasync(int fd, struct file *file, int on)
 408 {
 409         struct mousedev_client *client = file->private_data;
 410
 411         return fasync_helper(fd, file, on, &client->fasync);
 412 }
 413
 414 static void mousedev_free(struct device *dev)
 415 {
 416         struct mousedev *mousedev = container_of(dev, struct mousedev, dev);
 417
 418         input_put_device(mousedev->handle.dev);
 419         kfree(mousedev);
 420 }
 421
 422 static int mousedev_open_device(struct mousedev *mousedev)
 423 {
 424         int retval;
 425
 426         retval = mutex_lock_interruptible(&mousedev->mutex);
 427         if (retval)
 428                 return retval;
 429
 430         if (!mousedev->exist)
 431                 retval = -ENODEV;
 432         else if (!mousedev->open++) {
 433                 retval = input_open_device(&mousedev->handle);
 434                 if (retval)
 435                         mousedev->open--;
 436         }
 437
 438         mutex_unlock(&mousedev->mutex);
 439         return retval;
 440 }
 441
 442 static void mousedev_close_device(struct mousedev *mousedev)
 443 {
 444         mutex_lock(&mousedev->mutex);
 445
 446         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 int mixdev_open_devices(struct mousedev *mixdev)
 458 {
 459         int error;
 460
 461         error = mutex_lock_interruptible(&mixdev->mutex);
 462         if (error)
 463                 return error;
 464
 465         if (!mixdev->open++) {
 466                 struct mousedev *mousedev;
 467
 468                 list_for_each_entry(mousedev, &mousedev_mix_list, mixdev_node) {
 469                         if (!mousedev->opened_by_mixdev) {
 470                                 if (mousedev_open_device(mousedev))
 471                                         continue;
 472
 473                                 mousedev->opened_by_mixdev = true;
 474                         }
 475                 }
 476         }
 477
 478         mutex_unlock(&mixdev->mutex);
 479         return 0;
 480 }
 481
 482 /*
 483  * Close all devices that were opened as part of multiplexed
 484  * device. Note that this function is called with mousedev_mix->mutex
 485  * held.
 486  */
 487 static void mixdev_close_devices(struct mousedev *mixdev)
 488 {
 489         mutex_lock(&mixdev->mutex);
 490
 491         if (!--mixdev->open) {
 492                 struct mousedev *mousedev;
 493
 494                 list_for_each_entry(mousedev, &mousedev_mix_list, mixdev_node) {
 495                         if (mousedev->opened_by_mixdev) {
 496                                 mousedev->opened_by_mixdev = false;
 497                                 mousedev_close_device(mousedev);
 498                         }
 499                 }
 500         }
 501
 502         mutex_unlock(&mixdev->mutex);
 503 }
 504
 505
 506 static void mousedev_attach_client(struct mousedev *mousedev,
 507                                    struct mousedev_client *client)
 508 {
 509         spin_lock(&mousedev->client_lock);
 510         list_add_tail_rcu(&client->node, &mousedev->client_list);
 511         spin_unlock(&mousedev->client_lock);
 512 }
 513
 514 static void mousedev_detach_client(struct mousedev *mousedev,
 515                                    struct mousedev_client *client)
 516 {
 517         spin_lock(&mousedev->client_lock);
 518         list_del_rcu(&client->node);
 519         spin_unlock(&mousedev->client_lock);
 520         synchronize_rcu();
 521 }
 522
 523 static int mousedev_release(struct inode *inode, struct file *file)
 524 {
 525         struct mousedev_client *client = file->private_data;
 526         struct mousedev *mousedev = client->mousedev;
 527
 528         mousedev_detach_client(mousedev, client);
 529         kfree(client);
 530
 531         mousedev->close_device(mousedev);
 532
 533         return 0;
 534 }
 535
 536 static int mousedev_open(struct inode *inode, struct file *file)
 537 {
 538         struct mousedev_client *client;
 539         struct mousedev *mousedev;
 540         int error;
 541
 542 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
 543         if (imajor(inode) == MISC_MAJOR)
 544                 mousedev = mousedev_mix;
 545         else
 546 #endif
 547                 mousedev = container_of(inode->i_cdev, struct mousedev, cdev);
 548
 549         client = kzalloc(sizeof(struct mousedev_client), GFP_KERNEL);
 550         if (!client)
 551                 return -ENOMEM;
 552
 553         spin_lock_init(&client->packet_lock);
 554         client->pos_x = xres / 2;
 555         client->pos_y = yres / 2;
 556         client->mousedev = mousedev;
 557         mousedev_attach_client(mousedev, client);
 558
 559         error = mousedev->open_device(mousedev);
 560         if (error)
 561                 goto err_free_client;
 562
 563         file->private_data = client;
 564         nonseekable_open(inode, file);
 565
 566         return 0;
 567
 568  err_free_client:
 569         mousedev_detach_client(mousedev, client);
 570         kfree(client);
 571         return error;
 572 }
 573
 574 static inline int mousedev_limit_delta(int delta, int limit)
 575 {
 576         return delta > limit ? limit : (delta < -limit ? -limit : delta);
 577 }
 578
 579 static void mousedev_packet(struct mousedev_client *client,
 580                             signed char *ps2_data)
 581 {
 582         struct mousedev_motion *p = &client->packets[client->tail];
 583
 584         ps2_data[0] = 0x08 |
 585                 ((p->dx < 0) << 4) | ((p->dy < 0) << 5) | (p->buttons & 0x07);
 586         ps2_data[1] = mousedev_limit_delta(p->dx, 127);
 587         ps2_data[2] = mousedev_limit_delta(p->dy, 127);
 588         p->dx -= ps2_data[1];
 589         p->dy -= ps2_data[2];
 590
 591         switch (client->mode) {
 592         case MOUSEDEV_EMUL_EXPS:
 593                 ps2_data[3] = mousedev_limit_delta(p->dz, 7);
 594                 p->dz -= ps2_data[3];
 595                 ps2_data[3] = (ps2_data[3] & 0x0f) | ((p->buttons & 0x18) << 1);
 596                 client->bufsiz = 4;
 597                 break;
 598
 599         case MOUSEDEV_EMUL_IMPS:
 600                 ps2_data[0] |=
 601                         ((p->buttons & 0x10) >> 3) | ((p->buttons & 0x08) >> 1);
 602                 ps2_data[3] = mousedev_limit_delta(p->dz, 127);
 603                 p->dz -= ps2_data[3];
 604                 client->bufsiz = 4;
 605                 break;
 606
 607         case MOUSEDEV_EMUL_PS2:
 608         default:
 609                 ps2_data[0] |=
 610                         ((p->buttons & 0x10) >> 3) | ((p->buttons & 0x08) >> 1);
 611                 p->dz = 0;
 612                 client->bufsiz = 3;
 613                 break;
 614         }
 615
 616         if (!p->dx && !p->dy && !p->dz) {
 617                 if (client->tail == client->head) {
 618                         client->ready = 0;
 619                         client->last_buttons = p->buttons;
 620                 } else
 621                         client->tail = (client->tail + 1) % PACKET_QUEUE_LEN;
 622         }
 623 }
 624
 625 static void mousedev_generate_response(struct mousedev_client *client,
 626                                         int command)
 627 {
 628         client->ps2[0] = 0xfa; /* ACK */
 629
 630         switch (command) {
 631
 632         case 0xeb: /* Poll */
 633                 mousedev_packet(client, &client->ps2[1]);
 634                 client->bufsiz++; /* account for leading ACK */
 635                 break;
 636
 637         case 0xf2: /* Get ID */
 638                 switch (client->mode) {
 639                 case MOUSEDEV_EMUL_PS2:
 640                         client->ps2[1] = 0;
 641                         break;
 642                 case MOUSEDEV_EMUL_IMPS:
 643                         client->ps2[1] = 3;
 644                         break;
 645                 case MOUSEDEV_EMUL_EXPS:
 646                         client->ps2[1] = 4;
 647                         break;
 648                 }
 649                 client->bufsiz = 2;
 650                 break;
 651
 652         case 0xe9: /* Get info */
 653                 client->ps2[1] = 0x60; client->ps2[2] = 3; client->ps2[3] = 200;
 654                 client->bufsiz = 4;
 655                 break;
 656
 657         case 0xff: /* Reset */
 658                 client->impsseq = client->imexseq = 0;
 659                 client->mode = MOUSEDEV_EMUL_PS2;
 660                 client->ps2[1] = 0xaa; client->ps2[2] = 0x00;
 661                 client->bufsiz = 3;
 662                 break;
 663
 664         default:
 665                 client->bufsiz = 1;
 666                 break;
 667         }
 668         client->buffer = client->bufsiz;
 669 }
 670
 671 static ssize_t mousedev_write(struct file *file, const char __user *buffer,
 672                                 size_t count, loff_t *ppos)
 673 {
 674         struct mousedev_client *client = file->private_data;
 675         unsigned char c;
 676         unsigned int i;
 677
 678         for (i = 0; i < count; i++) {
 679
 680                 if (get_user(c, buffer + i))
 681                         return -EFAULT;
 682
 683                 spin_lock_irq(&client->packet_lock);
 684
 685                 if (c == mousedev_imex_seq[client->imexseq]) {
 686                         if (++client->imexseq == MOUSEDEV_SEQ_LEN) {
 687                                 client->imexseq = 0;
 688                                 client->mode = MOUSEDEV_EMUL_EXPS;
 689                         }
 690                 } else
 691                         client->imexseq = 0;
 692
 693                 if (c == mousedev_imps_seq[client->impsseq]) {
 694                         if (++client->impsseq == MOUSEDEV_SEQ_LEN) {
 695                                 client->impsseq = 0;
 696                                 client->mode = MOUSEDEV_EMUL_IMPS;
 697                         }
 698                 } else
 699                         client->impsseq = 0;
 700
 701                 mousedev_generate_response(client, c);
 702
 703                 spin_unlock_irq(&client->packet_lock);
 704         }
 705
 706         kill_fasync(&client->fasync, SIGIO, POLL_IN);
 707         wake_up_interruptible(&client->mousedev->wait);
 708
 709         return count;
 710 }
 711
 712 static ssize_t mousedev_read(struct file *file, char __user *buffer,
 713                              size_t count, loff_t *ppos)
 714 {
 715         struct mousedev_client *client = file->private_data;
 716         struct mousedev *mousedev = client->mousedev;
 717         signed char data[sizeof(client->ps2)];
 718         int retval = 0;
 719
 720         if (!client->ready && !client->buffer && mousedev->exist &&
 721             (file->f_flags & O_NONBLOCK))
 722                 return -EAGAIN;
 723
 724         retval = wait_event_interruptible(mousedev->wait,
 725                         !mousedev->exist || client->ready || client->buffer);
 726         if (retval)
 727                 return retval;
 728
 729         if (!mousedev->exist)
 730                 return -ENODEV;
 731
 732         spin_lock_irq(&client->packet_lock);
 733
 734         if (!client->buffer && client->ready) {
 735                 mousedev_packet(client, client->ps2);
 736                 client->buffer = client->bufsiz;
 737         }
 738
 739         if (count > client->buffer)
 740                 count = client->buffer;
 741
 742         memcpy(data, client->ps2 + client->bufsiz - client->buffer, count);
 743         client->buffer -= count;
 744
 745         spin_unlock_irq(&client->packet_lock);
 746
 747         if (copy_to_user(buffer, data, count))
 748                 return -EFAULT;
 749
 750         return count;
 751 }
 752
 753 /* No kernel lock - fine */
 754 static unsigned int mousedev_poll(struct file *file, poll_table *wait)
 755 {
 756         struct mousedev_client *client = file->private_data;
 757         struct mousedev *mousedev = client->mousedev;
 758         unsigned int mask;
 759
 760         poll_wait(file, &mousedev->wait, wait);
 761
 762         mask = mousedev->exist ? POLLOUT | POLLWRNORM : POLLHUP | POLLERR;
 763         if (client->ready || client->buffer)
 764                 mask |= POLLIN | POLLRDNORM;
 765
 766         return mask;
 767 }
 768
 769 static const struct file_operations mousedev_fops = {
 770         .owner          = THIS_MODULE,
 771         .read           = mousedev_read,
 772         .write          = mousedev_write,
 773         .poll           = mousedev_poll,
 774         .open           = mousedev_open,
 775         .release        = mousedev_release,
 776         .fasync         = mousedev_fasync,
 777         .llseek         = noop_llseek,
 778 };
 779
 780 /*
 781  * Mark device non-existent. This disables writes, ioctls and
 782  * prevents new users from opening the device. Already posted
 783  * blocking reads will stay, however new ones will fail.
 784  */
 785 static void mousedev_mark_dead(struct mousedev *mousedev)
 786 {
 787         mutex_lock(&mousedev->mutex);
 788         mousedev->exist = false;
 789         mutex_unlock(&mousedev->mutex);
 790 }
 791
 792 /*
 793  * Wake up users waiting for IO so they can disconnect from
 794  * dead device.
 795  */
 796 static void mousedev_hangup(struct mousedev *mousedev)
 797 {
 798         struct mousedev_client *client;
 799
 800         spin_lock(&mousedev->client_lock);
 801         list_for_each_entry(client, &mousedev->client_list, node)
 802                 kill_fasync(&client->fasync, SIGIO, POLL_HUP);
 803         spin_unlock(&mousedev->client_lock);
 804
 805         wake_up_interruptible(&mousedev->wait);
 806 }
 807
 808 static void mousedev_cleanup(struct mousedev *mousedev)
 809 {
 810         struct input_handle *handle = &mousedev->handle;
 811
 812         mousedev_mark_dead(mousedev);
 813         mousedev_hangup(mousedev);
 814
 815         cdev_del(&mousedev->cdev);
 816
 817         /* mousedev is marked dead so no one else accesses mousedev->open */
 818         if (mousedev->open)
 819                 input_close_device(handle);
 820 }
 821
 822 static int mousedev_reserve_minor(bool mixdev)
 823 {
 824         int minor;
 825
 826         if (mixdev) {
 827                 minor = input_get_new_minor(MOUSEDEV_MIX, 1, false);
 828                 if (minor < 0)
 829                         pr_err("failed to reserve mixdev minor: %d\n", minor);
 830         } else {
 831                 minor = input_get_new_minor(MOUSEDEV_MINOR_BASE,
 832                                             MOUSEDEV_MINORS, true);
 833                 if (minor < 0)
 834                         pr_err("failed to reserve new minor: %d\n", minor);
 835         }
 836
 837         return minor;
 838 }
 839
 840 static struct mousedev *mousedev_create(struct input_dev *dev,
 841                                         struct input_handler *handler,
 842                                         bool mixdev)
 843 {
 844         struct mousedev *mousedev;
 845         int minor;
 846         int error;
 847
 848         minor = mousedev_reserve_minor(mixdev);
 849         if (minor < 0) {
 850                 error = minor;
 851                 goto err_out;
 852         }
 853
 854         mousedev = kzalloc(sizeof(struct mousedev), GFP_KERNEL);
 855         if (!mousedev) {
 856                 error = -ENOMEM;
 857                 goto err_free_minor;
 858         }
 859
 860         INIT_LIST_HEAD(&mousedev->client_list);
 861         INIT_LIST_HEAD(&mousedev->mixdev_node);
 862         spin_lock_init(&mousedev->client_lock);
 863         mutex_init(&mousedev->mutex);
 864         lockdep_set_subclass(&mousedev->mutex,
 865                              mixdev ? SINGLE_DEPTH_NESTING : 0);
 866         init_waitqueue_head(&mousedev->wait);
 867
 868         if (mixdev) {
 869                 dev_set_name(&mousedev->dev, "mice");
 870
 871                 mousedev->open_device = mixdev_open_devices;
 872                 mousedev->close_device = mixdev_close_devices;
 873         } else {
 874                 int dev_no = minor;
 875                 /* Normalize device number if it falls into legacy range */
 876                 if (dev_no < MOUSEDEV_MINOR_BASE + MOUSEDEV_MINORS)
 877                         dev_no -= MOUSEDEV_MINOR_BASE;
 878                 dev_set_name(&mousedev->dev, "mouse%d", dev_no);
 879
 880                 mousedev->open_device = mousedev_open_device;
 881                 mousedev->close_device = mousedev_close_device;
 882         }
 883
 884         mousedev->exist = true;
 885         mousedev->handle.dev = input_get_device(dev);
 886         mousedev->handle.name = dev_name(&mousedev->dev);
 887         mousedev->handle.handler = handler;
 888         mousedev->handle.private = mousedev;
 889
 890         mousedev->dev.class = &input_class;
 891         if (dev)
 892                 mousedev->dev.parent = &dev->dev;
 893         mousedev->dev.devt = MKDEV(INPUT_MAJOR, minor);
 894         mousedev->dev.release = mousedev_free;
 895         device_initialize(&mousedev->dev);
 896
 897         if (!mixdev) {
 898                 error = input_register_handle(&mousedev->handle);
 899                 if (error)
 900                         goto err_free_mousedev;
 901         }
 902
 903         cdev_init(&mousedev->cdev, &mousedev_fops);
 904         mousedev->cdev.kobj.parent = &mousedev->dev.kobj;
 905         error = cdev_add(&mousedev->cdev, mousedev->dev.devt, 1);
 906         if (error)
 907                 goto err_unregister_handle;
 908
 909         error = device_add(&mousedev->dev);
 910         if (error)
 911                 goto err_cleanup_mousedev;
 912
 913         return mousedev;
 914
 915  err_cleanup_mousedev:
 916         mousedev_cleanup(mousedev);
 917  err_unregister_handle:
 918         if (!mixdev)
 919                 input_unregister_handle(&mousedev->handle);
 920  err_free_mousedev:
 921         put_device(&mousedev->dev);
 922  err_free_minor:
 923         input_free_minor(minor);
 924  err_out:
 925         return ERR_PTR(error);
 926 }
 927
 928 static void mousedev_destroy(struct mousedev *mousedev)
 929 {
 930         device_del(&mousedev->dev);
 931         mousedev_cleanup(mousedev);
 932         input_free_minor(MINOR(mousedev->dev.devt));
 933         if (mousedev != mousedev_mix)
 934                 input_unregister_handle(&mousedev->handle);
 935         put_device(&mousedev->dev);
 936 }
 937
 938 static int mixdev_add_device(struct mousedev *mousedev)
 939 {
 940         int retval;
 941
 942         retval = mutex_lock_interruptible(&mousedev_mix->mutex);
 943         if (retval)
 944                 return retval;
 945
 946         if (mousedev_mix->open) {
 947                 retval = mousedev_open_device(mousedev);
 948                 if (retval)
 949                         goto out;
 950
 951                 mousedev->opened_by_mixdev = true;
 952         }
 953
 954         get_device(&mousedev->dev);
 955         list_add_tail(&mousedev->mixdev_node, &mousedev_mix_list);
 956
 957  out:
 958         mutex_unlock(&mousedev_mix->mutex);
 959         return retval;
 960 }
 961
 962 static void mixdev_remove_device(struct mousedev *mousedev)
 963 {
 964         mutex_lock(&mousedev_mix->mutex);
 965
 966         if (mousedev->opened_by_mixdev) {
 967                 mousedev->opened_by_mixdev = false;
 968                 mousedev_close_device(mousedev);
 969         }
 970
 971         list_del_init(&mousedev->mixdev_node);
 972         mutex_unlock(&mousedev_mix->mutex);
 973
 974         put_device(&mousedev->dev);
 975 }
 976
 977 static int mousedev_connect(struct input_handler *handler,
 978                             struct input_dev *dev,
 979                             const struct input_device_id *id)
 980 {
 981         struct mousedev *mousedev;
 982         int error;
 983
 984         mousedev = mousedev_create(dev, handler, false);
 985         if (IS_ERR(mousedev))
 986                 return PTR_ERR(mousedev);
 987
 988         error = mixdev_add_device(mousedev);
 989         if (error) {
 990                 mousedev_destroy(mousedev);
 991                 return error;
 992         }
 993
 994         return 0;
 995 }
 996
 997 static void mousedev_disconnect(struct input_handle *handle)
 998 {
 999         struct mousedev *mousedev = handle->private;
1000
1001         mixdev_remove_device(mousedev);
1002         mousedev_destroy(mousedev);
1003 }
1004
1005 static const struct input_device_id mousedev_ids[] = {
1006         {
1007                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1008                                 INPUT_DEVICE_ID_MATCH_KEYBIT |
1009                                 INPUT_DEVICE_ID_MATCH_RELBIT,
1010                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_REL) },
1011                 .keybit = { [BIT_WORD(BTN_LEFT)] = BIT_MASK(BTN_LEFT) },
1012                 .relbit = { BIT_MASK(REL_X) | BIT_MASK(REL_Y) },
1013         },      /* A mouse like device, at least one button,
1014                    two relative axes */
1015         {
1016                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1017                                 INPUT_DEVICE_ID_MATCH_RELBIT,
1018                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_REL) },
1019                 .relbit = { BIT_MASK(REL_WHEEL) },
1020         },      /* A separate scrollwheel */
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_TOUCH)] = BIT_MASK(BTN_TOUCH) },
1027                 .absbit = { BIT_MASK(ABS_X) | BIT_MASK(ABS_Y) },
1028         },      /* A tablet like device, at least touch detection,
1029                    two absolute axes */
1030         {
1031                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1032                                 INPUT_DEVICE_ID_MATCH_KEYBIT |
1033                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
1034                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS) },
1035                 .keybit = { [BIT_WORD(BTN_TOOL_FINGER)] =
1036                                 BIT_MASK(BTN_TOOL_FINGER) },
1037                 .absbit = { BIT_MASK(ABS_X) | BIT_MASK(ABS_Y) |
1038                                 BIT_MASK(ABS_PRESSURE) |
1039                                 BIT_MASK(ABS_TOOL_WIDTH) },
1040         },      /* A touchpad */
1041         {
1042                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1043                         INPUT_DEVICE_ID_MATCH_KEYBIT |
1044                         INPUT_DEVICE_ID_MATCH_ABSBIT,
1045                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS) },
1046                 .keybit = { [BIT_WORD(BTN_LEFT)] = BIT_MASK(BTN_LEFT) },
1047                 .absbit = { BIT_MASK(ABS_X) | BIT_MASK(ABS_Y) },
1048         },      /* Mouse-like device with absolute X and Y but ordinary
1049                    clicks, like hp ILO2 High Performance mouse */
1050
1051         { },    /* Terminating entry */
1052 };
1053
1054 MODULE_DEVICE_TABLE(input, mousedev_ids);
1055
1056 static struct input_handler mousedev_handler = {
1057         .event          = mousedev_event,
1058         .connect        = mousedev_connect,
1059         .disconnect     = mousedev_disconnect,
1060         .legacy_minors  = true,
1061         .minor          = MOUSEDEV_MINOR_BASE,
1062         .name           = "mousedev",
1063         .id_table       = mousedev_ids,
1064 };
1065
1066 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
1067 #include <linux/miscdevice.h>
1068
1069 static struct miscdevice psaux_mouse = {
1070         .minor  = PSMOUSE_MINOR,
1071         .name   = "psaux",
1072         .fops   = &mousedev_fops,
1073 };
1074
1075 static bool psaux_registered;
1076
1077 static void __init mousedev_psaux_register(void)
1078 {
1079         int error;
1080
1081         error = misc_register(&psaux_mouse);
1082         if (error)
1083                 pr_warn("could not register psaux device, error: %d\n",
1084                            error);
1085         else
1086                 psaux_registered = true;
1087 }
1088
1089 static void __exit mousedev_psaux_unregister(void)
1090 {
1091         if (psaux_registered)
1092                 misc_deregister(&psaux_mouse);
1093 }
1094 #else
1095 static inline void mousedev_psaux_register(void) { }
1096 static inline void mousedev_psaux_unregister(void) { }
1097 #endif
1098
1099 static int __init mousedev_init(void)
1100 {
1101         int error;
1102
1103         mousedev_mix = mousedev_create(NULL, &mousedev_handler, true);
1104         if (IS_ERR(mousedev_mix))
1105                 return PTR_ERR(mousedev_mix);
1106
1107         error = input_register_handler(&mousedev_handler);
1108         if (error) {
1109                 mousedev_destroy(mousedev_mix);
1110                 return error;
1111         }
1112
1113         mousedev_psaux_register();
1114
1115         pr_info("PS/2 mouse device common for all mice\n");
1116
1117         return 0;
1118 }
1119
1120 static void __exit mousedev_exit(void)
1121 {
1122         mousedev_psaux_unregister();
1123         input_unregister_handler(&mousedev_handler);
1124         mousedev_destroy(mousedev_mix);
1125 }
1126
1127 module_init(mousedev_init);
1128 module_exit(mousedev_exit);