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/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         bool is_mixdev;
  71
  72         struct list_head mixdev_node;
  73         bool opened_by_mixdev;
  74
  75         struct mousedev_hw_data packet;
  76         unsigned int pkt_count;
  77         int old_x[4], old_y[4];
  78         int frac_dx, frac_dy;
  79         unsigned long touch;
  80 };
  81
  82 enum mousedev_emul {
  83         MOUSEDEV_EMUL_PS2,
  84         MOUSEDEV_EMUL_IMPS,
  85         MOUSEDEV_EMUL_EXPS
  86 };
  87
  88 struct mousedev_motion {
  89         int dx, dy, dz;
  90         unsigned long buttons;
  91 };
  92
  93 #define PACKET_QUEUE_LEN        16
  94 struct mousedev_client {
  95         struct fasync_struct *fasync;
  96         struct mousedev *mousedev;
  97         struct list_head node;
  98
  99         struct mousedev_motion packets[PACKET_QUEUE_LEN];
 100         unsigned int head, tail;
 101         spinlock_t packet_lock;
 102         int pos_x, pos_y;
 103
 104         signed char ps2[6];
 105         unsigned char ready, buffer, bufsiz;
 106         unsigned char imexseq, impsseq;
 107         enum mousedev_emul mode;
 108         unsigned long last_buttons;
 109 };
 110
 111 #define MOUSEDEV_SEQ_LEN        6
 112
 113 static unsigned char mousedev_imps_seq[] = { 0xf3, 200, 0xf3, 100, 0xf3, 80 };
 114 static unsigned char mousedev_imex_seq[] = { 0xf3, 200, 0xf3, 200, 0xf3, 80 };
 115
 116 static struct mousedev *mousedev_mix;
 117 static LIST_HEAD(mousedev_mix_list);
 118
 119 static void mixdev_open_devices(void);
 120 static void mixdev_close_devices(void);
 121
 122 #define fx(i)  (mousedev->old_x[(mousedev->pkt_count - (i)) & 03])
 123 #define fy(i)  (mousedev->old_y[(mousedev->pkt_count - (i)) & 03])
 124
 125 static void mousedev_touchpad_event(struct input_dev *dev,
 126                                     struct mousedev *mousedev,
 127                                     unsigned int code, int value)
 128 {
 129         int size, tmp;
 130         enum { FRACTION_DENOM = 128 };
 131
 132         switch (code) {
 133
 134         case ABS_X:
 135
 136                 fx(0) = value;
 137                 if (mousedev->touch && mousedev->pkt_count >= 2) {
 138                         size = input_abs_get_max(dev, ABS_X) -
 139                                         input_abs_get_min(dev, ABS_X);
 140                         if (size == 0)
 141                                 size = 256 * 2;
 142
 143                         tmp = ((value - fx(2)) * 256 * FRACTION_DENOM) / size;
 144                         tmp += mousedev->frac_dx;
 145                         mousedev->packet.dx = tmp / FRACTION_DENOM;
 146                         mousedev->frac_dx =
 147                                 tmp - mousedev->packet.dx * FRACTION_DENOM;
 148                 }
 149                 break;
 150
 151         case ABS_Y:
 152                 fy(0) = value;
 153                 if (mousedev->touch && mousedev->pkt_count >= 2) {
 154                         /* use X size for ABS_Y to keep the same scale */
 155                         size = input_abs_get_max(dev, ABS_X) -
 156                                         input_abs_get_min(dev, ABS_X);
 157                         if (size == 0)
 158                                 size = 256 * 2;
 159
 160                         tmp = -((value - fy(2)) * 256 * FRACTION_DENOM) / size;
 161                         tmp += mousedev->frac_dy;
 162                         mousedev->packet.dy = tmp / FRACTION_DENOM;
 163                         mousedev->frac_dy = tmp -
 164                                 mousedev->packet.dy * FRACTION_DENOM;
 165                 }
 166                 break;
 167         }
 168 }
 169
 170 static void mousedev_abs_event(struct input_dev *dev, struct mousedev *mousedev,
 171                                 unsigned int code, int value)
 172 {
 173         int min, max, size;
 174
 175         switch (code) {
 176
 177         case ABS_X:
 178                 min = input_abs_get_min(dev, ABS_X);
 179                 max = input_abs_get_max(dev, ABS_X);
 180
 181                 size = max - min;
 182                 if (size == 0)
 183                         size = xres ? : 1;
 184
 185                 value = clamp(value, min, max);
 186
 187                 mousedev->packet.x = ((value - min) * xres) / size;
 188                 mousedev->packet.abs_event = 1;
 189                 break;
 190
 191         case ABS_Y:
 192                 min = input_abs_get_min(dev, ABS_Y);
 193                 max = input_abs_get_max(dev, ABS_Y);
 194
 195                 size = max - min;
 196                 if (size == 0)
 197                         size = yres ? : 1;
 198
 199                 value = clamp(value, min, max);
 200
 201                 mousedev->packet.y = yres - ((value - min) * yres) / size;
 202                 mousedev->packet.abs_event = 1;
 203                 break;
 204         }
 205 }
 206
 207 static void mousedev_rel_event(struct mousedev *mousedev,
 208                                 unsigned int code, int value)
 209 {
 210         switch (code) {
 211         case REL_X:
 212                 mousedev->packet.dx += value;
 213                 break;
 214
 215         case REL_Y:
 216                 mousedev->packet.dy -= value;
 217                 break;
 218
 219         case REL_WHEEL:
 220                 mousedev->packet.dz -= value;
 221                 break;
 222         }
 223 }
 224
 225 static void mousedev_key_event(struct mousedev *mousedev,
 226                                 unsigned int code, int value)
 227 {
 228         int index;
 229
 230         switch (code) {
 231
 232         case BTN_TOUCH:
 233         case BTN_0:
 234         case BTN_LEFT:          index = 0; break;
 235
 236         case BTN_STYLUS:
 237         case BTN_1:
 238         case BTN_RIGHT:         index = 1; break;
 239
 240         case BTN_2:
 241         case BTN_FORWARD:
 242         case BTN_STYLUS2:
 243         case BTN_MIDDLE:        index = 2; break;
 244
 245         case BTN_3:
 246         case BTN_BACK:
 247         case BTN_SIDE:          index = 3; break;
 248
 249         case BTN_4:
 250         case BTN_EXTRA:         index = 4; break;
 251
 252         default:                return;
 253         }
 254
 255         if (value) {
 256                 set_bit(index, &mousedev->packet.buttons);
 257                 set_bit(index, &mousedev_mix->packet.buttons);
 258         } else {
 259                 clear_bit(index, &mousedev->packet.buttons);
 260                 clear_bit(index, &mousedev_mix->packet.buttons);
 261         }
 262 }
 263
 264 static void mousedev_notify_readers(struct mousedev *mousedev,
 265                                     struct mousedev_hw_data *packet)
 266 {
 267         struct mousedev_client *client;
 268         struct mousedev_motion *p;
 269         unsigned int new_head;
 270         int wake_readers = 0;
 271
 272         rcu_read_lock();
 273         list_for_each_entry_rcu(client, &mousedev->client_list, node) {
 274
 275                 /* Just acquire the lock, interrupts already disabled */
 276                 spin_lock(&client->packet_lock);
 277
 278                 p = &client->packets[client->head];
 279                 if (client->ready && p->buttons != mousedev->packet.buttons) {
 280                         new_head = (client->head + 1) % PACKET_QUEUE_LEN;
 281                         if (new_head != client->tail) {
 282                                 p = &client->packets[client->head = new_head];
 283                                 memset(p, 0, sizeof(struct mousedev_motion));
 284                         }
 285                 }
 286
 287                 if (packet->abs_event) {
 288                         p->dx += packet->x - client->pos_x;
 289                         p->dy += packet->y - client->pos_y;
 290                         client->pos_x = packet->x;
 291                         client->pos_y = packet->y;
 292                 }
 293
 294                 client->pos_x += packet->dx;
 295                 client->pos_x = client->pos_x < 0 ?
 296                         0 : (client->pos_x >= xres ? xres : client->pos_x);
 297                 client->pos_y += packet->dy;
 298                 client->pos_y = client->pos_y < 0 ?
 299                         0 : (client->pos_y >= yres ? yres : client->pos_y);
 300
 301                 p->dx += packet->dx;
 302                 p->dy += packet->dy;
 303                 p->dz += packet->dz;
 304                 p->buttons = mousedev->packet.buttons;
 305
 306                 if (p->dx || p->dy || p->dz ||
 307                     p->buttons != client->last_buttons)
 308                         client->ready = 1;
 309
 310                 spin_unlock(&client->packet_lock);
 311
 312                 if (client->ready) {
 313                         kill_fasync(&client->fasync, SIGIO, POLL_IN);
 314                         wake_readers = 1;
 315                 }
 316         }
 317         rcu_read_unlock();
 318
 319         if (wake_readers)
 320                 wake_up_interruptible(&mousedev->wait);
 321 }
 322
 323 static void mousedev_touchpad_touch(struct mousedev *mousedev, int value)
 324 {
 325         if (!value) {
 326                 if (mousedev->touch &&
 327                     time_before(jiffies,
 328                                 mousedev->touch + msecs_to_jiffies(tap_time))) {
 329                         /*
 330                          * Toggle left button to emulate tap.
 331                          * We rely on the fact that mousedev_mix always has 0
 332                          * motion packet so we won't mess current position.
 333                          */
 334                         set_bit(0, &mousedev->packet.buttons);
 335                         set_bit(0, &mousedev_mix->packet.buttons);
 336                         mousedev_notify_readers(mousedev, &mousedev_mix->packet);
 337                         mousedev_notify_readers(mousedev_mix,
 338                                                 &mousedev_mix->packet);
 339                         clear_bit(0, &mousedev->packet.buttons);
 340                         clear_bit(0, &mousedev_mix->packet.buttons);
 341                 }
 342                 mousedev->touch = mousedev->pkt_count = 0;
 343                 mousedev->frac_dx = 0;
 344                 mousedev->frac_dy = 0;
 345
 346         } else if (!mousedev->touch)
 347                 mousedev->touch = jiffies;
 348 }
 349
 350 static void mousedev_event(struct input_handle *handle,
 351                            unsigned int type, unsigned int code, int value)
 352 {
 353         struct mousedev *mousedev = handle->private;
 354
 355         switch (type) {
 356
 357         case EV_ABS:
 358                 /* Ignore joysticks */
 359                 if (test_bit(BTN_TRIGGER, handle->dev->keybit))
 360                         return;
 361
 362                 if (test_bit(BTN_TOOL_FINGER, handle->dev->keybit))
 363                         mousedev_touchpad_event(handle->dev,
 364                                                 mousedev, code, value);
 365                 else
 366                         mousedev_abs_event(handle->dev, mousedev, code, value);
 367
 368                 break;
 369
 370         case EV_REL:
 371                 mousedev_rel_event(mousedev, code, value);
 372                 break;
 373
 374         case EV_KEY:
 375                 if (value != 2) {
 376                         if (code == BTN_TOUCH &&
 377                             test_bit(BTN_TOOL_FINGER, handle->dev->keybit))
 378                                 mousedev_touchpad_touch(mousedev, value);
 379                         else
 380                                 mousedev_key_event(mousedev, code, value);
 381                 }
 382                 break;
 383
 384         case EV_SYN:
 385                 if (code == SYN_REPORT) {
 386                         if (mousedev->touch) {
 387                                 mousedev->pkt_count++;
 388                                 /*
 389                                  * Input system eats duplicate events,
 390                                  * but we need all of them to do correct
 391                                  * averaging so apply present one forward
 392                                  */
 393                                 fx(0) = fx(1);
 394                                 fy(0) = fy(1);
 395                         }
 396
 397                         mousedev_notify_readers(mousedev, &mousedev->packet);
 398                         mousedev_notify_readers(mousedev_mix, &mousedev->packet);
 399
 400                         mousedev->packet.dx = mousedev->packet.dy =
 401                                 mousedev->packet.dz = 0;
 402                         mousedev->packet.abs_event = 0;
 403                 }
 404                 break;
 405         }
 406 }
 407
 408 static int mousedev_fasync(int fd, struct file *file, int on)
 409 {
 410         struct mousedev_client *client = file->private_data;
 411
 412         return fasync_helper(fd, file, on, &client->fasync);
 413 }
 414
 415 static void mousedev_free(struct device *dev)
 416 {
 417         struct mousedev *mousedev = container_of(dev, struct mousedev, dev);
 418
 419         input_put_device(mousedev->handle.dev);
 420         kfree(mousedev);
 421 }
 422
 423 static int mousedev_open_device(struct mousedev *mousedev)
 424 {
 425         int retval;
 426
 427         retval = mutex_lock_interruptible(&mousedev->mutex);
 428         if (retval)
 429                 return retval;
 430
 431         if (mousedev->is_mixdev)
 432                 mixdev_open_devices();
 433         else if (!mousedev->exist)
 434                 retval = -ENODEV;
 435         else if (!mousedev->open++) {
 436                 retval = input_open_device(&mousedev->handle);
 437                 if (retval)
 438                         mousedev->open--;
 439         }
 440
 441         mutex_unlock(&mousedev->mutex);
 442         return retval;
 443 }
 444
 445 static void mousedev_close_device(struct mousedev *mousedev)
 446 {
 447         mutex_lock(&mousedev->mutex);
 448
 449         if (mousedev->is_mixdev)
 450                 mixdev_close_devices();
 451         else if (mousedev->exist && !--mousedev->open)
 452                 input_close_device(&mousedev->handle);
 453
 454         mutex_unlock(&mousedev->mutex);
 455 }
 456
 457 /*
 458  * Open all available devices so they can all be multiplexed in one.
 459  * stream. Note that this function is called with mousedev_mix->mutex
 460  * held.
 461  */
 462 static void mixdev_open_devices(void)
 463 {
 464         struct mousedev *mousedev;
 465
 466         if (mousedev_mix->open++)
 467                 return;
 468
 469         list_for_each_entry(mousedev, &mousedev_mix_list, mixdev_node) {
 470                 if (!mousedev->opened_by_mixdev) {
 471                         if (mousedev_open_device(mousedev))
 472                                 continue;
 473
 474                         mousedev->opened_by_mixdev = true;
 475                 }
 476         }
 477 }
 478
 479 /*
 480  * Close all devices that were opened as part of multiplexed
 481  * device. Note that this function is called with mousedev_mix->mutex
 482  * held.
 483  */
 484 static void mixdev_close_devices(void)
 485 {
 486         struct mousedev *mousedev;
 487
 488         if (--mousedev_mix->open)
 489                 return;
 490
 491         list_for_each_entry(mousedev, &mousedev_mix_list, mixdev_node) {
 492                 if (mousedev->opened_by_mixdev) {
 493                         mousedev->opened_by_mixdev = false;
 494                         mousedev_close_device(mousedev);
 495                 }
 496         }
 497 }
 498
 499
 500 static void mousedev_attach_client(struct mousedev *mousedev,
 501                                    struct mousedev_client *client)
 502 {
 503         spin_lock(&mousedev->client_lock);
 504         list_add_tail_rcu(&client->node, &mousedev->client_list);
 505         spin_unlock(&mousedev->client_lock);
 506 }
 507
 508 static void mousedev_detach_client(struct mousedev *mousedev,
 509                                    struct mousedev_client *client)
 510 {
 511         spin_lock(&mousedev->client_lock);
 512         list_del_rcu(&client->node);
 513         spin_unlock(&mousedev->client_lock);
 514         synchronize_rcu();
 515 }
 516
 517 static int mousedev_release(struct inode *inode, struct file *file)
 518 {
 519         struct mousedev_client *client = file->private_data;
 520         struct mousedev *mousedev = client->mousedev;
 521
 522         mousedev_detach_client(mousedev, client);
 523         kfree(client);
 524
 525         mousedev_close_device(mousedev);
 526         put_device(&mousedev->dev);
 527
 528         return 0;
 529 }
 530
 531 static int mousedev_open(struct inode *inode, struct file *file)
 532 {
 533         struct mousedev_client *client;
 534         struct mousedev *mousedev;
 535         int error;
 536
 537 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
 538         if (imajor(inode) == MISC_MAJOR)
 539                 mousedev = mousedev_mix;
 540         else
 541 #endif
 542                 mousedev = container_of(inode->i_cdev, struct mousedev, cdev);
 543
 544         client = kzalloc(sizeof(struct mousedev_client), GFP_KERNEL);
 545         if (!client)
 546                 return -ENOMEM;
 547
 548         spin_lock_init(&client->packet_lock);
 549         client->pos_x = xres / 2;
 550         client->pos_y = yres / 2;
 551         client->mousedev = mousedev;
 552         mousedev_attach_client(mousedev, client);
 553
 554         error = mousedev_open_device(mousedev);
 555         if (error)
 556                 goto err_free_client;
 557
 558         file->private_data = client;
 559         nonseekable_open(inode, file);
 560
 561         get_device(&mousedev->dev);
 562         return 0;
 563
 564  err_free_client:
 565         mousedev_detach_client(mousedev, client);
 566         kfree(client);
 567         return error;
 568 }
 569
 570 static inline int mousedev_limit_delta(int delta, int limit)
 571 {
 572         return delta > limit ? limit : (delta < -limit ? -limit : delta);
 573 }
 574
 575 static void mousedev_packet(struct mousedev_client *client,
 576                             signed char *ps2_data)
 577 {
 578         struct mousedev_motion *p = &client->packets[client->tail];
 579
 580         ps2_data[0] = 0x08 |
 581                 ((p->dx < 0) << 4) | ((p->dy < 0) << 5) | (p->buttons & 0x07);
 582         ps2_data[1] = mousedev_limit_delta(p->dx, 127);
 583         ps2_data[2] = mousedev_limit_delta(p->dy, 127);
 584         p->dx -= ps2_data[1];
 585         p->dy -= ps2_data[2];
 586
 587         switch (client->mode) {
 588         case MOUSEDEV_EMUL_EXPS:
 589                 ps2_data[3] = mousedev_limit_delta(p->dz, 7);
 590                 p->dz -= ps2_data[3];
 591                 ps2_data[3] = (ps2_data[3] & 0x0f) | ((p->buttons & 0x18) << 1);
 592                 client->bufsiz = 4;
 593                 break;
 594
 595         case MOUSEDEV_EMUL_IMPS:
 596                 ps2_data[0] |=
 597                         ((p->buttons & 0x10) >> 3) | ((p->buttons & 0x08) >> 1);
 598                 ps2_data[3] = mousedev_limit_delta(p->dz, 127);
 599                 p->dz -= ps2_data[3];
 600                 client->bufsiz = 4;
 601                 break;
 602
 603         case MOUSEDEV_EMUL_PS2:
 604         default:
 605                 ps2_data[0] |=
 606                         ((p->buttons & 0x10) >> 3) | ((p->buttons & 0x08) >> 1);
 607                 p->dz = 0;
 608                 client->bufsiz = 3;
 609                 break;
 610         }
 611
 612         if (!p->dx && !p->dy && !p->dz) {
 613                 if (client->tail == client->head) {
 614                         client->ready = 0;
 615                         client->last_buttons = p->buttons;
 616                 } else
 617                         client->tail = (client->tail + 1) % PACKET_QUEUE_LEN;
 618         }
 619 }
 620
 621 static void mousedev_generate_response(struct mousedev_client *client,
 622                                         int command)
 623 {
 624         client->ps2[0] = 0xfa; /* ACK */
 625
 626         switch (command) {
 627
 628         case 0xeb: /* Poll */
 629                 mousedev_packet(client, &client->ps2[1]);
 630                 client->bufsiz++; /* account for leading ACK */
 631                 break;
 632
 633         case 0xf2: /* Get ID */
 634                 switch (client->mode) {
 635                 case MOUSEDEV_EMUL_PS2:
 636                         client->ps2[1] = 0;
 637                         break;
 638                 case MOUSEDEV_EMUL_IMPS:
 639                         client->ps2[1] = 3;
 640                         break;
 641                 case MOUSEDEV_EMUL_EXPS:
 642                         client->ps2[1] = 4;
 643                         break;
 644                 }
 645                 client->bufsiz = 2;
 646                 break;
 647
 648         case 0xe9: /* Get info */
 649                 client->ps2[1] = 0x60; client->ps2[2] = 3; client->ps2[3] = 200;
 650                 client->bufsiz = 4;
 651                 break;
 652
 653         case 0xff: /* Reset */
 654                 client->impsseq = client->imexseq = 0;
 655                 client->mode = MOUSEDEV_EMUL_PS2;
 656                 client->ps2[1] = 0xaa; client->ps2[2] = 0x00;
 657                 client->bufsiz = 3;
 658                 break;
 659
 660         default:
 661                 client->bufsiz = 1;
 662                 break;
 663         }
 664         client->buffer = client->bufsiz;
 665 }
 666
 667 static ssize_t mousedev_write(struct file *file, const char __user *buffer,
 668                                 size_t count, loff_t *ppos)
 669 {
 670         struct mousedev_client *client = file->private_data;
 671         unsigned char c;
 672         unsigned int i;
 673
 674         for (i = 0; i < count; i++) {
 675
 676                 if (get_user(c, buffer + i))
 677                         return -EFAULT;
 678
 679                 spin_lock_irq(&client->packet_lock);
 680
 681                 if (c == mousedev_imex_seq[client->imexseq]) {
 682                         if (++client->imexseq == MOUSEDEV_SEQ_LEN) {
 683                                 client->imexseq = 0;
 684                                 client->mode = MOUSEDEV_EMUL_EXPS;
 685                         }
 686                 } else
 687                         client->imexseq = 0;
 688
 689                 if (c == mousedev_imps_seq[client->impsseq]) {
 690                         if (++client->impsseq == MOUSEDEV_SEQ_LEN) {
 691                                 client->impsseq = 0;
 692                                 client->mode = MOUSEDEV_EMUL_IMPS;
 693                         }
 694                 } else
 695                         client->impsseq = 0;
 696
 697                 mousedev_generate_response(client, c);
 698
 699                 spin_unlock_irq(&client->packet_lock);
 700         }
 701
 702         kill_fasync(&client->fasync, SIGIO, POLL_IN);
 703         wake_up_interruptible(&client->mousedev->wait);
 704
 705         return count;
 706 }
 707
 708 static ssize_t mousedev_read(struct file *file, char __user *buffer,
 709                              size_t count, loff_t *ppos)
 710 {
 711         struct mousedev_client *client = file->private_data;
 712         struct mousedev *mousedev = client->mousedev;
 713         signed char data[sizeof(client->ps2)];
 714         int retval = 0;
 715
 716         if (!client->ready && !client->buffer && mousedev->exist &&
 717             (file->f_flags & O_NONBLOCK))
 718                 return -EAGAIN;
 719
 720         retval = wait_event_interruptible(mousedev->wait,
 721                         !mousedev->exist || client->ready || client->buffer);
 722         if (retval)
 723                 return retval;
 724
 725         if (!mousedev->exist)
 726                 return -ENODEV;
 727
 728         spin_lock_irq(&client->packet_lock);
 729
 730         if (!client->buffer && client->ready) {
 731                 mousedev_packet(client, client->ps2);
 732                 client->buffer = client->bufsiz;
 733         }
 734
 735         if (count > client->buffer)
 736                 count = client->buffer;
 737
 738         memcpy(data, client->ps2 + client->bufsiz - client->buffer, count);
 739         client->buffer -= count;
 740
 741         spin_unlock_irq(&client->packet_lock);
 742
 743         if (copy_to_user(buffer, data, count))
 744                 return -EFAULT;
 745
 746         return count;
 747 }
 748
 749 /* No kernel lock - fine */
 750 static unsigned int mousedev_poll(struct file *file, poll_table *wait)
 751 {
 752         struct mousedev_client *client = file->private_data;
 753         struct mousedev *mousedev = client->mousedev;
 754         unsigned int mask;
 755
 756         poll_wait(file, &mousedev->wait, wait);
 757
 758         mask = mousedev->exist ? POLLOUT | POLLWRNORM : POLLHUP | POLLERR;
 759         if (client->ready || client->buffer)
 760                 mask |= POLLIN | POLLRDNORM;
 761
 762         return mask;
 763 }
 764
 765 static const struct file_operations mousedev_fops = {
 766         .owner          = THIS_MODULE,
 767         .read           = mousedev_read,
 768         .write          = mousedev_write,
 769         .poll           = mousedev_poll,
 770         .open           = mousedev_open,
 771         .release        = mousedev_release,
 772         .fasync         = mousedev_fasync,
 773         .llseek         = noop_llseek,
 774 };
 775
 776 /*
 777  * Mark device non-existent. This disables writes, ioctls and
 778  * prevents new users from opening the device. Already posted
 779  * blocking reads will stay, however new ones will fail.
 780  */
 781 static void mousedev_mark_dead(struct mousedev *mousedev)
 782 {
 783         mutex_lock(&mousedev->mutex);
 784         mousedev->exist = false;
 785         mutex_unlock(&mousedev->mutex);
 786 }
 787
 788 /*
 789  * Wake up users waiting for IO so they can disconnect from
 790  * dead device.
 791  */
 792 static void mousedev_hangup(struct mousedev *mousedev)
 793 {
 794         struct mousedev_client *client;
 795
 796         spin_lock(&mousedev->client_lock);
 797         list_for_each_entry(client, &mousedev->client_list, node)
 798                 kill_fasync(&client->fasync, SIGIO, POLL_HUP);
 799         spin_unlock(&mousedev->client_lock);
 800
 801         wake_up_interruptible(&mousedev->wait);
 802 }
 803
 804 static void mousedev_cleanup(struct mousedev *mousedev)
 805 {
 806         struct input_handle *handle = &mousedev->handle;
 807
 808         mousedev_mark_dead(mousedev);
 809         mousedev_hangup(mousedev);
 810
 811         cdev_del(&mousedev->cdev);
 812
 813         /* mousedev is marked dead so no one else accesses mousedev->open */
 814         if (mousedev->open)
 815                 input_close_device(handle);
 816 }
 817
 818 static int mousedev_reserve_minor(bool mixdev)
 819 {
 820         int minor;
 821
 822         if (mixdev) {
 823                 minor = input_get_new_minor(MOUSEDEV_MIX, 1, false);
 824                 if (minor < 0)
 825                         pr_err("failed to reserve mixdev minor: %d\n", minor);
 826         } else {
 827                 minor = input_get_new_minor(MOUSEDEV_MINOR_BASE,
 828                                             MOUSEDEV_MINORS, true);
 829                 if (minor < 0)
 830                         pr_err("failed to reserve new minor: %d\n", minor);
 831         }
 832
 833         return minor;
 834 }
 835
 836 static struct mousedev *mousedev_create(struct input_dev *dev,
 837                                         struct input_handler *handler,
 838                                         bool mixdev)
 839 {
 840         struct mousedev *mousedev;
 841         int minor;
 842         int error;
 843
 844         minor = mousedev_reserve_minor(mixdev);
 845         if (minor < 0) {
 846                 error = minor;
 847                 goto err_out;
 848         }
 849
 850         mousedev = kzalloc(sizeof(struct mousedev), GFP_KERNEL);
 851         if (!mousedev) {
 852                 error = -ENOMEM;
 853                 goto err_free_minor;
 854         }
 855
 856         INIT_LIST_HEAD(&mousedev->client_list);
 857         INIT_LIST_HEAD(&mousedev->mixdev_node);
 858         spin_lock_init(&mousedev->client_lock);
 859         mutex_init(&mousedev->mutex);
 860         lockdep_set_subclass(&mousedev->mutex,
 861                              mixdev ? SINGLE_DEPTH_NESTING : 0);
 862         init_waitqueue_head(&mousedev->wait);
 863
 864         if (mixdev) {
 865                 dev_set_name(&mousedev->dev, "mice");
 866         } else {
 867                 int dev_no = minor;
 868                 /* Normalize device number if it falls into legacy range */
 869                 if (dev_no < MOUSEDEV_MINOR_BASE + MOUSEDEV_MINORS)
 870                         dev_no -= MOUSEDEV_MINOR_BASE;
 871                 dev_set_name(&mousedev->dev, "mouse%d", dev_no);
 872         }
 873
 874         mousedev->exist = true;
 875         mousedev->is_mixdev = mixdev;
 876         mousedev->handle.dev = input_get_device(dev);
 877         mousedev->handle.name = dev_name(&mousedev->dev);
 878         mousedev->handle.handler = handler;
 879         mousedev->handle.private = mousedev;
 880
 881         mousedev->dev.class = &input_class;
 882         if (dev)
 883                 mousedev->dev.parent = &dev->dev;
 884         mousedev->dev.devt = MKDEV(INPUT_MAJOR, minor);
 885         mousedev->dev.release = mousedev_free;
 886         device_initialize(&mousedev->dev);
 887
 888         if (!mixdev) {
 889                 error = input_register_handle(&mousedev->handle);
 890                 if (error)
 891                         goto err_free_mousedev;
 892         }
 893
 894         cdev_init(&mousedev->cdev, &mousedev_fops);
 895         error = cdev_add(&mousedev->cdev, mousedev->dev.devt, 1);
 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 (!mixdev)
 909                 input_unregister_handle(&mousedev->handle);
 910  err_free_mousedev:
 911         put_device(&mousedev->dev);
 912  err_free_minor:
 913         input_free_minor(minor);
 914  err_out:
 915         return ERR_PTR(error);
 916 }
 917
 918 static void mousedev_destroy(struct mousedev *mousedev)
 919 {
 920         device_del(&mousedev->dev);
 921         mousedev_cleanup(mousedev);
 922         input_free_minor(MINOR(mousedev->dev.devt));
 923         if (!mousedev->is_mixdev)
 924                 input_unregister_handle(&mousedev->handle);
 925         put_device(&mousedev->dev);
 926 }
 927
 928 static int mixdev_add_device(struct mousedev *mousedev)
 929 {
 930         int retval;
 931
 932         retval = mutex_lock_interruptible(&mousedev_mix->mutex);
 933         if (retval)
 934                 return retval;
 935
 936         if (mousedev_mix->open) {
 937                 retval = mousedev_open_device(mousedev);
 938                 if (retval)
 939                         goto out;
 940
 941                 mousedev->opened_by_mixdev = true;
 942         }
 943
 944         get_device(&mousedev->dev);
 945         list_add_tail(&mousedev->mixdev_node, &mousedev_mix_list);
 946
 947  out:
 948         mutex_unlock(&mousedev_mix->mutex);
 949         return retval;
 950 }
 951
 952 static void mixdev_remove_device(struct mousedev *mousedev)
 953 {
 954         mutex_lock(&mousedev_mix->mutex);
 955
 956         if (mousedev->opened_by_mixdev) {
 957                 mousedev->opened_by_mixdev = false;
 958                 mousedev_close_device(mousedev);
 959         }
 960
 961         list_del_init(&mousedev->mixdev_node);
 962         mutex_unlock(&mousedev_mix->mutex);
 963
 964         put_device(&mousedev->dev);
 965 }
 966
 967 static int mousedev_connect(struct input_handler *handler,
 968                             struct input_dev *dev,
 969                             const struct input_device_id *id)
 970 {
 971         struct mousedev *mousedev;
 972         int error;
 973
 974         mousedev = mousedev_create(dev, handler, false);
 975         if (IS_ERR(mousedev))
 976                 return PTR_ERR(mousedev);
 977
 978         error = mixdev_add_device(mousedev);
 979         if (error) {
 980                 mousedev_destroy(mousedev);
 981                 return error;
 982         }
 983
 984         return 0;
 985 }
 986
 987 static void mousedev_disconnect(struct input_handle *handle)
 988 {
 989         struct mousedev *mousedev = handle->private;
 990
 991         mixdev_remove_device(mousedev);
 992         mousedev_destroy(mousedev);
 993 }
 994
 995 static const struct input_device_id mousedev_ids[] = {
 996         {
 997                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 998                                 INPUT_DEVICE_ID_MATCH_KEYBIT |
 999                                 INPUT_DEVICE_ID_MATCH_RELBIT,
1000                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_REL) },
1001                 .keybit = { [BIT_WORD(BTN_LEFT)] = BIT_MASK(BTN_LEFT) },
1002                 .relbit = { BIT_MASK(REL_X) | BIT_MASK(REL_Y) },
1003         },      /* A mouse like device, at least one button,
1004                    two relative axes */
1005         {
1006                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1007                                 INPUT_DEVICE_ID_MATCH_RELBIT,
1008                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_REL) },
1009                 .relbit = { BIT_MASK(REL_WHEEL) },
1010         },      /* A separate scrollwheel */
1011         {
1012                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1013                                 INPUT_DEVICE_ID_MATCH_KEYBIT |
1014                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
1015                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS) },
1016                 .keybit = { [BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH) },
1017                 .absbit = { BIT_MASK(ABS_X) | BIT_MASK(ABS_Y) },
1018         },      /* A tablet like device, at least touch detection,
1019                    two absolute axes */
1020         {
1021                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1022                                 INPUT_DEVICE_ID_MATCH_KEYBIT |
1023                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
1024                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS) },
1025                 .keybit = { [BIT_WORD(BTN_TOOL_FINGER)] =
1026                                 BIT_MASK(BTN_TOOL_FINGER) },
1027                 .absbit = { BIT_MASK(ABS_X) | BIT_MASK(ABS_Y) |
1028                                 BIT_MASK(ABS_PRESSURE) |
1029                                 BIT_MASK(ABS_TOOL_WIDTH) },
1030         },      /* A touchpad */
1031         {
1032                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1033                         INPUT_DEVICE_ID_MATCH_KEYBIT |
1034                         INPUT_DEVICE_ID_MATCH_ABSBIT,
1035                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS) },
1036                 .keybit = { [BIT_WORD(BTN_LEFT)] = BIT_MASK(BTN_LEFT) },
1037                 .absbit = { BIT_MASK(ABS_X) | BIT_MASK(ABS_Y) },
1038         },      /* Mouse-like device with absolute X and Y but ordinary
1039                    clicks, like hp ILO2 High Performance mouse */
1040
1041         { },    /* Terminating entry */
1042 };
1043
1044 MODULE_DEVICE_TABLE(input, mousedev_ids);
1045
1046 static struct input_handler mousedev_handler = {
1047         .event          = mousedev_event,
1048         .connect        = mousedev_connect,
1049         .disconnect     = mousedev_disconnect,
1050         .legacy_minors  = true,
1051         .minor          = MOUSEDEV_MINOR_BASE,
1052         .name           = "mousedev",
1053         .id_table       = mousedev_ids,
1054 };
1055
1056 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
1057 #include <linux/miscdevice.h>
1058
1059 static struct miscdevice psaux_mouse = {
1060         .minor  = PSMOUSE_MINOR,
1061         .name   = "psaux",
1062         .fops   = &mousedev_fops,
1063 };
1064
1065 static bool psaux_registered;
1066
1067 static void __init mousedev_psaux_register(void)
1068 {
1069         int error;
1070
1071         error = misc_register(&psaux_mouse);
1072         if (error)
1073                 pr_warn("could not register psaux device, error: %d\n",
1074                            error);
1075         else
1076                 psaux_registered = true;
1077 }
1078
1079 static void __exit mousedev_psaux_unregister(void)
1080 {
1081         if (psaux_registered)
1082                 misc_deregister(&psaux_mouse);
1083 }
1084 #else
1085 static inline void mousedev_psaux_register(void) { }
1086 static inline void mousedev_psaux_unregister(void) { }
1087 #endif
1088
1089 static int __init mousedev_init(void)
1090 {
1091         int error;
1092
1093         mousedev_mix = mousedev_create(NULL, &mousedev_handler, true);
1094         if (IS_ERR(mousedev_mix))
1095                 return PTR_ERR(mousedev_mix);
1096
1097         error = input_register_handler(&mousedev_handler);
1098         if (error) {
1099                 mousedev_destroy(mousedev_mix);
1100                 return error;
1101         }
1102
1103         mousedev_psaux_register();
1104
1105         pr_info("PS/2 mouse device common for all mice\n");
1106
1107         return 0;
1108 }
1109
1110 static void __exit mousedev_exit(void)
1111 {
1112         mousedev_psaux_unregister();
1113         input_unregister_handler(&mousedev_handler);
1114         mousedev_destroy(mousedev_mix);
1115 }
1116
1117 module_init(mousedev_init);
1118 module_exit(mousedev_exit);