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         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
 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->mixdev_open) {
 473                         if (mousedev_open_device(mousedev))
 474                                 continue;
 475
 476                         mousedev->mixdev_open = 1;
 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->mixdev_open) {
 495                         mousedev->mixdev_open = 0;
 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         return 0;
 580
 581  err_free_client:
 582         mousedev_detach_client(mousedev, client);
 583         kfree(client);
 584  err_put_mousedev:
 585         put_device(&mousedev->dev);
 586         return error;
 587 }
 588
 589 static inline int mousedev_limit_delta(int delta, int limit)
 590 {
 591         return delta > limit ? limit : (delta < -limit ? -limit : delta);
 592 }
 593
 594 static void mousedev_packet(struct mousedev_client *client,
 595                             signed char *ps2_data)
 596 {
 597         struct mousedev_motion *p = &client->packets[client->tail];
 598
 599         ps2_data[0] = 0x08 |
 600                 ((p->dx < 0) << 4) | ((p->dy < 0) << 5) | (p->buttons & 0x07);
 601         ps2_data[1] = mousedev_limit_delta(p->dx, 127);
 602         ps2_data[2] = mousedev_limit_delta(p->dy, 127);
 603         p->dx -= ps2_data[1];
 604         p->dy -= ps2_data[2];
 605
 606         switch (client->mode) {
 607         case MOUSEDEV_EMUL_EXPS:
 608                 ps2_data[3] = mousedev_limit_delta(p->dz, 7);
 609                 p->dz -= ps2_data[3];
 610                 ps2_data[3] = (ps2_data[3] & 0x0f) | ((p->buttons & 0x18) << 1);
 611                 client->bufsiz = 4;
 612                 break;
 613
 614         case MOUSEDEV_EMUL_IMPS:
 615                 ps2_data[0] |=
 616                         ((p->buttons & 0x10) >> 3) | ((p->buttons & 0x08) >> 1);
 617                 ps2_data[3] = mousedev_limit_delta(p->dz, 127);
 618                 p->dz -= ps2_data[3];
 619                 client->bufsiz = 4;
 620                 break;
 621
 622         case MOUSEDEV_EMUL_PS2:
 623         default:
 624                 ps2_data[0] |=
 625                         ((p->buttons & 0x10) >> 3) | ((p->buttons & 0x08) >> 1);
 626                 p->dz = 0;
 627                 client->bufsiz = 3;
 628                 break;
 629         }
 630
 631         if (!p->dx && !p->dy && !p->dz) {
 632                 if (client->tail == client->head) {
 633                         client->ready = 0;
 634                         client->last_buttons = p->buttons;
 635                 } else
 636                         client->tail = (client->tail + 1) % PACKET_QUEUE_LEN;
 637         }
 638 }
 639
 640 static void mousedev_generate_response(struct mousedev_client *client,
 641                                         int command)
 642 {
 643         client->ps2[0] = 0xfa; /* ACK */
 644
 645         switch (command) {
 646
 647         case 0xeb: /* Poll */
 648                 mousedev_packet(client, &client->ps2[1]);
 649                 client->bufsiz++; /* account for leading ACK */
 650                 break;
 651
 652         case 0xf2: /* Get ID */
 653                 switch (client->mode) {
 654                 case MOUSEDEV_EMUL_PS2:
 655                         client->ps2[1] = 0;
 656                         break;
 657                 case MOUSEDEV_EMUL_IMPS:
 658                         client->ps2[1] = 3;
 659                         break;
 660                 case MOUSEDEV_EMUL_EXPS:
 661                         client->ps2[1] = 4;
 662                         break;
 663                 }
 664                 client->bufsiz = 2;
 665                 break;
 666
 667         case 0xe9: /* Get info */
 668                 client->ps2[1] = 0x60; client->ps2[2] = 3; client->ps2[3] = 200;
 669                 client->bufsiz = 4;
 670                 break;
 671
 672         case 0xff: /* Reset */
 673                 client->impsseq = client->imexseq = 0;
 674                 client->mode = MOUSEDEV_EMUL_PS2;
 675                 client->ps2[1] = 0xaa; client->ps2[2] = 0x00;
 676                 client->bufsiz = 3;
 677                 break;
 678
 679         default:
 680                 client->bufsiz = 1;
 681                 break;
 682         }
 683         client->buffer = client->bufsiz;
 684 }
 685
 686 static ssize_t mousedev_write(struct file *file, const char __user *buffer,
 687                                 size_t count, loff_t *ppos)
 688 {
 689         struct mousedev_client *client = file->private_data;
 690         unsigned char c;
 691         unsigned int i;
 692
 693         for (i = 0; i < count; i++) {
 694
 695                 if (get_user(c, buffer + i))
 696                         return -EFAULT;
 697
 698                 spin_lock_irq(&client->packet_lock);
 699
 700                 if (c == mousedev_imex_seq[client->imexseq]) {
 701                         if (++client->imexseq == MOUSEDEV_SEQ_LEN) {
 702                                 client->imexseq = 0;
 703                                 client->mode = MOUSEDEV_EMUL_EXPS;
 704                         }
 705                 } else
 706                         client->imexseq = 0;
 707
 708                 if (c == mousedev_imps_seq[client->impsseq]) {
 709                         if (++client->impsseq == MOUSEDEV_SEQ_LEN) {
 710                                 client->impsseq = 0;
 711                                 client->mode = MOUSEDEV_EMUL_IMPS;
 712                         }
 713                 } else
 714                         client->impsseq = 0;
 715
 716                 mousedev_generate_response(client, c);
 717
 718                 spin_unlock_irq(&client->packet_lock);
 719         }
 720
 721         kill_fasync(&client->fasync, SIGIO, POLL_IN);
 722         wake_up_interruptible(&client->mousedev->wait);
 723
 724         return count;
 725 }
 726
 727 static ssize_t mousedev_read(struct file *file, char __user *buffer,
 728                              size_t count, loff_t *ppos)
 729 {
 730         struct mousedev_client *client = file->private_data;
 731         struct mousedev *mousedev = client->mousedev;
 732         signed char data[sizeof(client->ps2)];
 733         int retval = 0;
 734
 735         if (!client->ready && !client->buffer && mousedev->exist &&
 736             (file->f_flags & O_NONBLOCK))
 737                 return -EAGAIN;
 738
 739         retval = wait_event_interruptible(mousedev->wait,
 740                         !mousedev->exist || client->ready || client->buffer);
 741         if (retval)
 742                 return retval;
 743
 744         if (!mousedev->exist)
 745                 return -ENODEV;
 746
 747         spin_lock_irq(&client->packet_lock);
 748
 749         if (!client->buffer && client->ready) {
 750                 mousedev_packet(client, client->ps2);
 751                 client->buffer = client->bufsiz;
 752         }
 753
 754         if (count > client->buffer)
 755                 count = client->buffer;
 756
 757         memcpy(data, client->ps2 + client->bufsiz - client->buffer, count);
 758         client->buffer -= count;
 759
 760         spin_unlock_irq(&client->packet_lock);
 761
 762         if (copy_to_user(buffer, data, count))
 763                 return -EFAULT;
 764
 765         return count;
 766 }
 767
 768 /* No kernel lock - fine */
 769 static unsigned int mousedev_poll(struct file *file, poll_table *wait)
 770 {
 771         struct mousedev_client *client = file->private_data;
 772         struct mousedev *mousedev = client->mousedev;
 773         unsigned int mask;
 774
 775         poll_wait(file, &mousedev->wait, wait);
 776
 777         mask = mousedev->exist ? POLLOUT | POLLWRNORM : POLLHUP | POLLERR;
 778         if (client->ready || client->buffer)
 779                 mask |= POLLIN | POLLRDNORM;
 780
 781         return mask;
 782 }
 783
 784 static const struct file_operations mousedev_fops = {
 785         .owner          = THIS_MODULE,
 786         .read           = mousedev_read,
 787         .write          = mousedev_write,
 788         .poll           = mousedev_poll,
 789         .open           = mousedev_open,
 790         .release        = mousedev_release,
 791         .fasync         = mousedev_fasync,
 792         .llseek         = noop_llseek,
 793 };
 794
 795 static int mousedev_install_chrdev(struct mousedev *mousedev)
 796 {
 797         mousedev_table[mousedev->minor] = mousedev;
 798         return 0;
 799 }
 800
 801 static void mousedev_remove_chrdev(struct mousedev *mousedev)
 802 {
 803         mutex_lock(&mousedev_table_mutex);
 804         mousedev_table[mousedev->minor] = NULL;
 805         mutex_unlock(&mousedev_table_mutex);
 806 }
 807
 808 /*
 809  * Mark device non-existent. This disables writes, ioctls and
 810  * prevents new users from opening the device. Already posted
 811  * blocking reads will stay, however new ones will fail.
 812  */
 813 static void mousedev_mark_dead(struct mousedev *mousedev)
 814 {
 815         mutex_lock(&mousedev->mutex);
 816         mousedev->exist = false;
 817         mutex_unlock(&mousedev->mutex);
 818 }
 819
 820 /*
 821  * Wake up users waiting for IO so they can disconnect from
 822  * dead device.
 823  */
 824 static void mousedev_hangup(struct mousedev *mousedev)
 825 {
 826         struct mousedev_client *client;
 827
 828         spin_lock(&mousedev->client_lock);
 829         list_for_each_entry(client, &mousedev->client_list, node)
 830                 kill_fasync(&client->fasync, SIGIO, POLL_HUP);
 831         spin_unlock(&mousedev->client_lock);
 832
 833         wake_up_interruptible(&mousedev->wait);
 834 }
 835
 836 static void mousedev_cleanup(struct mousedev *mousedev)
 837 {
 838         struct input_handle *handle = &mousedev->handle;
 839
 840         mousedev_mark_dead(mousedev);
 841         mousedev_hangup(mousedev);
 842         mousedev_remove_chrdev(mousedev);
 843
 844         /* mousedev is marked dead so no one else accesses mousedev->open */
 845         if (mousedev->open)
 846                 input_close_device(handle);
 847 }
 848
 849 static struct mousedev *mousedev_create(struct input_dev *dev,
 850                                         struct input_handler *handler,
 851                                         int minor)
 852 {
 853         struct mousedev *mousedev;
 854         int error;
 855
 856         mousedev = kzalloc(sizeof(struct mousedev), GFP_KERNEL);
 857         if (!mousedev) {
 858                 error = -ENOMEM;
 859                 goto err_out;
 860         }
 861
 862         INIT_LIST_HEAD(&mousedev->client_list);
 863         INIT_LIST_HEAD(&mousedev->mixdev_node);
 864         spin_lock_init(&mousedev->client_lock);
 865         mutex_init(&mousedev->mutex);
 866         lockdep_set_subclass(&mousedev->mutex,
 867                              minor == MOUSEDEV_MIX ? SINGLE_DEPTH_NESTING : 0);
 868         init_waitqueue_head(&mousedev->wait);
 869
 870         if (minor == MOUSEDEV_MIX)
 871                 dev_set_name(&mousedev->dev, "mice");
 872         else
 873                 dev_set_name(&mousedev->dev, "mouse%d", minor);
 874
 875         mousedev->minor = minor;
 876         mousedev->exist = true;
 877         mousedev->handle.dev = input_get_device(dev);
 878         mousedev->handle.name = dev_name(&mousedev->dev);
 879         mousedev->handle.handler = handler;
 880         mousedev->handle.private = mousedev;
 881
 882         mousedev->dev.class = &input_class;
 883         if (dev)
 884                 mousedev->dev.parent = &dev->dev;
 885         mousedev->dev.devt = MKDEV(INPUT_MAJOR, MOUSEDEV_MINOR_BASE + minor);
 886         mousedev->dev.release = mousedev_free;
 887         device_initialize(&mousedev->dev);
 888
 889         if (minor != MOUSEDEV_MIX) {
 890                 error = input_register_handle(&mousedev->handle);
 891                 if (error)
 892                         goto err_free_mousedev;
 893         }
 894
 895         error = mousedev_install_chrdev(mousedev);
 896         if (error)
 897                 goto err_unregister_handle;
 898
 899         error = device_add(&mousedev->dev);
 900         if (error)
 901                 goto err_cleanup_mousedev;
 902
 903         return mousedev;
 904
 905  err_cleanup_mousedev:
 906         mousedev_cleanup(mousedev);
 907  err_unregister_handle:
 908         if (minor != MOUSEDEV_MIX)
 909                 input_unregister_handle(&mousedev->handle);
 910  err_free_mousedev:
 911         put_device(&mousedev->dev);
 912  err_out:
 913         return ERR_PTR(error);
 914 }
 915
 916 static void mousedev_destroy(struct mousedev *mousedev)
 917 {
 918         device_del(&mousedev->dev);
 919         mousedev_cleanup(mousedev);
 920         if (mousedev->minor != MOUSEDEV_MIX)
 921                 input_unregister_handle(&mousedev->handle);
 922         put_device(&mousedev->dev);
 923 }
 924
 925 static int mixdev_add_device(struct mousedev *mousedev)
 926 {
 927         int retval;
 928
 929         retval = mutex_lock_interruptible(&mousedev_mix->mutex);
 930         if (retval)
 931                 return retval;
 932
 933         if (mousedev_mix->open) {
 934                 retval = mousedev_open_device(mousedev);
 935                 if (retval)
 936                         goto out;
 937
 938                 mousedev->mixdev_open = 1;
 939         }
 940
 941         get_device(&mousedev->dev);
 942         list_add_tail(&mousedev->mixdev_node, &mousedev_mix_list);
 943
 944  out:
 945         mutex_unlock(&mousedev_mix->mutex);
 946         return retval;
 947 }
 948
 949 static void mixdev_remove_device(struct mousedev *mousedev)
 950 {
 951         mutex_lock(&mousedev_mix->mutex);
 952
 953         if (mousedev->mixdev_open) {
 954                 mousedev->mixdev_open = 0;
 955                 mousedev_close_device(mousedev);
 956         }
 957
 958         list_del_init(&mousedev->mixdev_node);
 959         mutex_unlock(&mousedev_mix->mutex);
 960
 961         put_device(&mousedev->dev);
 962 }
 963
 964 static int mousedev_connect(struct input_handler *handler,
 965                             struct input_dev *dev,
 966                             const struct input_device_id *id)
 967 {
 968         struct mousedev *mousedev;
 969         int minor;
 970         int error;
 971
 972         for (minor = 0; minor < MOUSEDEV_MINORS; minor++)
 973                 if (!mousedev_table[minor])
 974                         break;
 975
 976         if (minor == MOUSEDEV_MINORS) {
 977                 pr_err("no more free mousedev devices\n");
 978                 return -ENFILE;
 979         }
 980
 981         mousedev = mousedev_create(dev, handler, minor);
 982         if (IS_ERR(mousedev))
 983                 return PTR_ERR(mousedev);
 984
 985         error = mixdev_add_device(mousedev);
 986         if (error) {
 987                 mousedev_destroy(mousedev);
 988                 return error;
 989         }
 990
 991         return 0;
 992 }
 993
 994 static void mousedev_disconnect(struct input_handle *handle)
 995 {
 996         struct mousedev *mousedev = handle->private;
 997
 998         mixdev_remove_device(mousedev);
 999         mousedev_destroy(mousedev);
1000 }
1001
1002 static const struct input_device_id mousedev_ids[] = {
1003         {
1004                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1005                                 INPUT_DEVICE_ID_MATCH_KEYBIT |
1006                                 INPUT_DEVICE_ID_MATCH_RELBIT,
1007                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_REL) },
1008                 .keybit = { [BIT_WORD(BTN_LEFT)] = BIT_MASK(BTN_LEFT) },
1009                 .relbit = { BIT_MASK(REL_X) | BIT_MASK(REL_Y) },
1010         },      /* A mouse like device, at least one button,
1011                    two relative axes */
1012         {
1013                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1014                                 INPUT_DEVICE_ID_MATCH_RELBIT,
1015                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_REL) },
1016                 .relbit = { BIT_MASK(REL_WHEEL) },
1017         },      /* A separate scrollwheel */
1018         {
1019                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1020                                 INPUT_DEVICE_ID_MATCH_KEYBIT |
1021                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
1022                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS) },
1023                 .keybit = { [BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH) },
1024                 .absbit = { BIT_MASK(ABS_X) | BIT_MASK(ABS_Y) },
1025         },      /* A tablet like device, at least touch detection,
1026                    two absolute axes */
1027         {
1028                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1029                                 INPUT_DEVICE_ID_MATCH_KEYBIT |
1030                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
1031                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS) },
1032                 .keybit = { [BIT_WORD(BTN_TOOL_FINGER)] =
1033                                 BIT_MASK(BTN_TOOL_FINGER) },
1034                 .absbit = { BIT_MASK(ABS_X) | BIT_MASK(ABS_Y) |
1035                                 BIT_MASK(ABS_PRESSURE) |
1036                                 BIT_MASK(ABS_TOOL_WIDTH) },
1037         },      /* A touchpad */
1038         {
1039                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1040                         INPUT_DEVICE_ID_MATCH_KEYBIT |
1041                         INPUT_DEVICE_ID_MATCH_ABSBIT,
1042                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS) },
1043                 .keybit = { [BIT_WORD(BTN_LEFT)] = BIT_MASK(BTN_LEFT) },
1044                 .absbit = { BIT_MASK(ABS_X) | BIT_MASK(ABS_Y) },
1045         },      /* Mouse-like device with absolute X and Y but ordinary
1046                    clicks, like hp ILO2 High Performance mouse */
1047
1048         { },    /* Terminating entry */
1049 };
1050
1051 MODULE_DEVICE_TABLE(input, mousedev_ids);
1052
1053 static struct input_handler mousedev_handler = {
1054         .event          = mousedev_event,
1055         .connect        = mousedev_connect,
1056         .disconnect     = mousedev_disconnect,
1057         .fops           = &mousedev_fops,
1058         .minor          = MOUSEDEV_MINOR_BASE,
1059         .name           = "mousedev",
1060         .id_table       = mousedev_ids,
1061 };
1062
1063 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
1064 #include <linux/miscdevice.h>
1065
1066 static struct miscdevice psaux_mouse = {
1067         .minor  = PSMOUSE_MINOR,
1068         .name   = "psaux",
1069         .fops   = &mousedev_fops,
1070 };
1071
1072 static bool psaux_registered;
1073
1074 static void __init mousedev_psaux_register(void)
1075 {
1076         int error;
1077
1078         error = misc_register(&psaux_mouse);
1079         if (error)
1080                 pr_warn("could not register psaux device, error: %d\n",
1081                            error);
1082         else
1083                 psaux_registered = true;
1084 }
1085
1086 static void __exit mousedev_psaux_unregister(void)
1087 {
1088         if (psaux_registered)
1089                 misc_deregister(&psaux_mouse);
1090 }
1091 #else
1092 static inline void mousedev_psaux_register(void) { }
1093 static inline void mousedev_psaux_unregister(void) { }
1094 #endif
1095
1096 static int __init mousedev_init(void)
1097 {
1098         int error;
1099
1100         mousedev_mix = mousedev_create(NULL, &mousedev_handler, MOUSEDEV_MIX);
1101         if (IS_ERR(mousedev_mix))
1102                 return PTR_ERR(mousedev_mix);
1103
1104         error = input_register_handler(&mousedev_handler);
1105         if (error) {
1106                 mousedev_destroy(mousedev_mix);
1107                 return error;
1108         }
1109
1110         mousedev_psaux_register();
1111
1112         pr_info("PS/2 mouse device common for all mice\n");
1113
1114         return 0;
1115 }
1116
1117 static void __exit mousedev_exit(void)
1118 {
1119         mousedev_psaux_unregister();
1120         input_unregister_handler(&mousedev_handler);
1121         mousedev_destroy(mousedev_mix);
1122 }
1123
1124 module_init(mousedev_init);
1125 module_exit(mousedev_exit);