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         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
 527         return 0;
 528 }
 529
 530 static int mousedev_open(struct inode *inode, struct file *file)
 531 {
 532         struct mousedev_client *client;
 533         struct mousedev *mousedev;
 534         int error;
 535
 536 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
 537         if (imajor(inode) == MISC_MAJOR)
 538                 mousedev = mousedev_mix;
 539         else
 540 #endif
 541                 mousedev = container_of(inode->i_cdev, struct mousedev, cdev);
 542
 543         client = kzalloc(sizeof(struct mousedev_client), GFP_KERNEL);
 544         if (!client)
 545                 return -ENOMEM;
 546
 547         spin_lock_init(&client->packet_lock);
 548         client->pos_x = xres / 2;
 549         client->pos_y = yres / 2;
 550         client->mousedev = mousedev;
 551         mousedev_attach_client(mousedev, client);
 552
 553         error = mousedev_open_device(mousedev);
 554         if (error)
 555                 goto err_free_client;
 556
 557         file->private_data = client;
 558         nonseekable_open(inode, file);
 559
 560         return 0;
 561
 562  err_free_client:
 563         mousedev_detach_client(mousedev, client);
 564         kfree(client);
 565         return error;
 566 }
 567
 568 static inline int mousedev_limit_delta(int delta, int limit)
 569 {
 570         return delta > limit ? limit : (delta < -limit ? -limit : delta);
 571 }
 572
 573 static void mousedev_packet(struct mousedev_client *client,
 574                             signed char *ps2_data)
 575 {
 576         struct mousedev_motion *p = &client->packets[client->tail];
 577
 578         ps2_data[0] = 0x08 |
 579                 ((p->dx < 0) << 4) | ((p->dy < 0) << 5) | (p->buttons & 0x07);
 580         ps2_data[1] = mousedev_limit_delta(p->dx, 127);
 581         ps2_data[2] = mousedev_limit_delta(p->dy, 127);
 582         p->dx -= ps2_data[1];
 583         p->dy -= ps2_data[2];
 584
 585         switch (client->mode) {
 586         case MOUSEDEV_EMUL_EXPS:
 587                 ps2_data[3] = mousedev_limit_delta(p->dz, 7);
 588                 p->dz -= ps2_data[3];
 589                 ps2_data[3] = (ps2_data[3] & 0x0f) | ((p->buttons & 0x18) << 1);
 590                 client->bufsiz = 4;
 591                 break;
 592
 593         case MOUSEDEV_EMUL_IMPS:
 594                 ps2_data[0] |=
 595                         ((p->buttons & 0x10) >> 3) | ((p->buttons & 0x08) >> 1);
 596                 ps2_data[3] = mousedev_limit_delta(p->dz, 127);
 597                 p->dz -= ps2_data[3];
 598                 client->bufsiz = 4;
 599                 break;
 600
 601         case MOUSEDEV_EMUL_PS2:
 602         default:
 603                 ps2_data[0] |=
 604                         ((p->buttons & 0x10) >> 3) | ((p->buttons & 0x08) >> 1);
 605                 p->dz = 0;
 606                 client->bufsiz = 3;
 607                 break;
 608         }
 609
 610         if (!p->dx && !p->dy && !p->dz) {
 611                 if (client->tail == client->head) {
 612                         client->ready = 0;
 613                         client->last_buttons = p->buttons;
 614                 } else
 615                         client->tail = (client->tail + 1) % PACKET_QUEUE_LEN;
 616         }
 617 }
 618
 619 static void mousedev_generate_response(struct mousedev_client *client,
 620                                         int command)
 621 {
 622         client->ps2[0] = 0xfa; /* ACK */
 623
 624         switch (command) {
 625
 626         case 0xeb: /* Poll */
 627                 mousedev_packet(client, &client->ps2[1]);
 628                 client->bufsiz++; /* account for leading ACK */
 629                 break;
 630
 631         case 0xf2: /* Get ID */
 632                 switch (client->mode) {
 633                 case MOUSEDEV_EMUL_PS2:
 634                         client->ps2[1] = 0;
 635                         break;
 636                 case MOUSEDEV_EMUL_IMPS:
 637                         client->ps2[1] = 3;
 638                         break;
 639                 case MOUSEDEV_EMUL_EXPS:
 640                         client->ps2[1] = 4;
 641                         break;
 642                 }
 643                 client->bufsiz = 2;
 644                 break;
 645
 646         case 0xe9: /* Get info */
 647                 client->ps2[1] = 0x60; client->ps2[2] = 3; client->ps2[3] = 200;
 648                 client->bufsiz = 4;
 649                 break;
 650
 651         case 0xff: /* Reset */
 652                 client->impsseq = client->imexseq = 0;
 653                 client->mode = MOUSEDEV_EMUL_PS2;
 654                 client->ps2[1] = 0xaa; client->ps2[2] = 0x00;
 655                 client->bufsiz = 3;
 656                 break;
 657
 658         default:
 659                 client->bufsiz = 1;
 660                 break;
 661         }
 662         client->buffer = client->bufsiz;
 663 }
 664
 665 static ssize_t mousedev_write(struct file *file, const char __user *buffer,
 666                                 size_t count, loff_t *ppos)
 667 {
 668         struct mousedev_client *client = file->private_data;
 669         unsigned char c;
 670         unsigned int i;
 671
 672         for (i = 0; i < count; i++) {
 673
 674                 if (get_user(c, buffer + i))
 675                         return -EFAULT;
 676
 677                 spin_lock_irq(&client->packet_lock);
 678
 679                 if (c == mousedev_imex_seq[client->imexseq]) {
 680                         if (++client->imexseq == MOUSEDEV_SEQ_LEN) {
 681                                 client->imexseq = 0;
 682                                 client->mode = MOUSEDEV_EMUL_EXPS;
 683                         }
 684                 } else
 685                         client->imexseq = 0;
 686
 687                 if (c == mousedev_imps_seq[client->impsseq]) {
 688                         if (++client->impsseq == MOUSEDEV_SEQ_LEN) {
 689                                 client->impsseq = 0;
 690                                 client->mode = MOUSEDEV_EMUL_IMPS;
 691                         }
 692                 } else
 693                         client->impsseq = 0;
 694
 695                 mousedev_generate_response(client, c);
 696
 697                 spin_unlock_irq(&client->packet_lock);
 698         }
 699
 700         kill_fasync(&client->fasync, SIGIO, POLL_IN);
 701         wake_up_interruptible(&client->mousedev->wait);
 702
 703         return count;
 704 }
 705
 706 static ssize_t mousedev_read(struct file *file, char __user *buffer,
 707                              size_t count, loff_t *ppos)
 708 {
 709         struct mousedev_client *client = file->private_data;
 710         struct mousedev *mousedev = client->mousedev;
 711         signed char data[sizeof(client->ps2)];
 712         int retval = 0;
 713
 714         if (!client->ready && !client->buffer && mousedev->exist &&
 715             (file->f_flags & O_NONBLOCK))
 716                 return -EAGAIN;
 717
 718         retval = wait_event_interruptible(mousedev->wait,
 719                         !mousedev->exist || client->ready || client->buffer);
 720         if (retval)
 721                 return retval;
 722
 723         if (!mousedev->exist)
 724                 return -ENODEV;
 725
 726         spin_lock_irq(&client->packet_lock);
 727
 728         if (!client->buffer && client->ready) {
 729                 mousedev_packet(client, client->ps2);
 730                 client->buffer = client->bufsiz;
 731         }
 732
 733         if (count > client->buffer)
 734                 count = client->buffer;
 735
 736         memcpy(data, client->ps2 + client->bufsiz - client->buffer, count);
 737         client->buffer -= count;
 738
 739         spin_unlock_irq(&client->packet_lock);
 740
 741         if (copy_to_user(buffer, data, count))
 742                 return -EFAULT;
 743
 744         return count;
 745 }
 746
 747 /* No kernel lock - fine */
 748 static unsigned int mousedev_poll(struct file *file, poll_table *wait)
 749 {
 750         struct mousedev_client *client = file->private_data;
 751         struct mousedev *mousedev = client->mousedev;
 752         unsigned int mask;
 753
 754         poll_wait(file, &mousedev->wait, wait);
 755
 756         mask = mousedev->exist ? POLLOUT | POLLWRNORM : POLLHUP | POLLERR;
 757         if (client->ready || client->buffer)
 758                 mask |= POLLIN | POLLRDNORM;
 759
 760         return mask;
 761 }
 762
 763 static const struct file_operations mousedev_fops = {
 764         .owner          = THIS_MODULE,
 765         .read           = mousedev_read,
 766         .write          = mousedev_write,
 767         .poll           = mousedev_poll,
 768         .open           = mousedev_open,
 769         .release        = mousedev_release,
 770         .fasync         = mousedev_fasync,
 771         .llseek         = noop_llseek,
 772 };
 773
 774 /*
 775  * Mark device non-existent. This disables writes, ioctls and
 776  * prevents new users from opening the device. Already posted
 777  * blocking reads will stay, however new ones will fail.
 778  */
 779 static void mousedev_mark_dead(struct mousedev *mousedev)
 780 {
 781         mutex_lock(&mousedev->mutex);
 782         mousedev->exist = false;
 783         mutex_unlock(&mousedev->mutex);
 784 }
 785
 786 /*
 787  * Wake up users waiting for IO so they can disconnect from
 788  * dead device.
 789  */
 790 static void mousedev_hangup(struct mousedev *mousedev)
 791 {
 792         struct mousedev_client *client;
 793
 794         spin_lock(&mousedev->client_lock);
 795         list_for_each_entry(client, &mousedev->client_list, node)
 796                 kill_fasync(&client->fasync, SIGIO, POLL_HUP);
 797         spin_unlock(&mousedev->client_lock);
 798
 799         wake_up_interruptible(&mousedev->wait);
 800 }
 801
 802 static void mousedev_cleanup(struct mousedev *mousedev)
 803 {
 804         struct input_handle *handle = &mousedev->handle;
 805
 806         mousedev_mark_dead(mousedev);
 807         mousedev_hangup(mousedev);
 808
 809         cdev_del(&mousedev->cdev);
 810
 811         /* mousedev is marked dead so no one else accesses mousedev->open */
 812         if (mousedev->open)
 813                 input_close_device(handle);
 814 }
 815
 816 static int mousedev_reserve_minor(bool mixdev)
 817 {
 818         int minor;
 819
 820         if (mixdev) {
 821                 minor = input_get_new_minor(MOUSEDEV_MIX, 1, false);
 822                 if (minor < 0)
 823                         pr_err("failed to reserve mixdev minor: %d\n", minor);
 824         } else {
 825                 minor = input_get_new_minor(MOUSEDEV_MINOR_BASE,
 826                                             MOUSEDEV_MINORS, true);
 827                 if (minor < 0)
 828                         pr_err("failed to reserve new minor: %d\n", minor);
 829         }
 830
 831         return minor;
 832 }
 833
 834 static struct mousedev *mousedev_create(struct input_dev *dev,
 835                                         struct input_handler *handler,
 836                                         bool mixdev)
 837 {
 838         struct mousedev *mousedev;
 839         int minor;
 840         int error;
 841
 842         minor = mousedev_reserve_minor(mixdev);
 843         if (minor < 0) {
 844                 error = minor;
 845                 goto err_out;
 846         }
 847
 848         mousedev = kzalloc(sizeof(struct mousedev), GFP_KERNEL);
 849         if (!mousedev) {
 850                 error = -ENOMEM;
 851                 goto err_free_minor;
 852         }
 853
 854         INIT_LIST_HEAD(&mousedev->client_list);
 855         INIT_LIST_HEAD(&mousedev->mixdev_node);
 856         spin_lock_init(&mousedev->client_lock);
 857         mutex_init(&mousedev->mutex);
 858         lockdep_set_subclass(&mousedev->mutex,
 859                              mixdev ? SINGLE_DEPTH_NESTING : 0);
 860         init_waitqueue_head(&mousedev->wait);
 861
 862         if (mixdev) {
 863                 dev_set_name(&mousedev->dev, "mice");
 864         } else {
 865                 int dev_no = minor;
 866                 /* Normalize device number if it falls into legacy range */
 867                 if (dev_no < MOUSEDEV_MINOR_BASE + MOUSEDEV_MINORS)
 868                         dev_no -= MOUSEDEV_MINOR_BASE;
 869                 dev_set_name(&mousedev->dev, "mouse%d", dev_no);
 870         }
 871
 872         mousedev->exist = true;
 873         mousedev->is_mixdev = mixdev;
 874         mousedev->handle.dev = input_get_device(dev);
 875         mousedev->handle.name = dev_name(&mousedev->dev);
 876         mousedev->handle.handler = handler;
 877         mousedev->handle.private = mousedev;
 878
 879         mousedev->dev.class = &input_class;
 880         if (dev)
 881                 mousedev->dev.parent = &dev->dev;
 882         mousedev->dev.devt = MKDEV(INPUT_MAJOR, minor);
 883         mousedev->dev.release = mousedev_free;
 884         device_initialize(&mousedev->dev);
 885
 886         if (!mixdev) {
 887                 error = input_register_handle(&mousedev->handle);
 888                 if (error)
 889                         goto err_free_mousedev;
 890         }
 891
 892         cdev_init(&mousedev->cdev, &mousedev_fops);
 893         mousedev->cdev.kobj.parent = &mousedev->dev.kobj;
 894         error = cdev_add(&mousedev->cdev, mousedev->dev.devt, 1);
 895         if (error)
 896                 goto err_unregister_handle;
 897
 898         error = device_add(&mousedev->dev);
 899         if (error)
 900                 goto err_cleanup_mousedev;
 901
 902         return mousedev;
 903
 904  err_cleanup_mousedev:
 905         mousedev_cleanup(mousedev);
 906  err_unregister_handle:
 907         if (!mixdev)
 908                 input_unregister_handle(&mousedev->handle);
 909  err_free_mousedev:
 910         put_device(&mousedev->dev);
 911  err_free_minor:
 912         input_free_minor(minor);
 913  err_out:
 914         return ERR_PTR(error);
 915 }
 916
 917 static void mousedev_destroy(struct mousedev *mousedev)
 918 {
 919         device_del(&mousedev->dev);
 920         mousedev_cleanup(mousedev);
 921         input_free_minor(MINOR(mousedev->dev.devt));
 922         if (!mousedev->is_mixdev)
 923                 input_unregister_handle(&mousedev->handle);
 924         put_device(&mousedev->dev);
 925 }
 926
 927 static int mixdev_add_device(struct mousedev *mousedev)
 928 {
 929         int retval;
 930
 931         retval = mutex_lock_interruptible(&mousedev_mix->mutex);
 932         if (retval)
 933                 return retval;
 934
 935         if (mousedev_mix->open) {
 936                 retval = mousedev_open_device(mousedev);
 937                 if (retval)
 938                         goto out;
 939
 940                 mousedev->opened_by_mixdev = true;
 941         }
 942
 943         get_device(&mousedev->dev);
 944         list_add_tail(&mousedev->mixdev_node, &mousedev_mix_list);
 945
 946  out:
 947         mutex_unlock(&mousedev_mix->mutex);
 948         return retval;
 949 }
 950
 951 static void mixdev_remove_device(struct mousedev *mousedev)
 952 {
 953         mutex_lock(&mousedev_mix->mutex);
 954
 955         if (mousedev->opened_by_mixdev) {
 956                 mousedev->opened_by_mixdev = false;
 957                 mousedev_close_device(mousedev);
 958         }
 959
 960         list_del_init(&mousedev->mixdev_node);
 961         mutex_unlock(&mousedev_mix->mutex);
 962
 963         put_device(&mousedev->dev);
 964 }
 965
 966 static int mousedev_connect(struct input_handler *handler,
 967                             struct input_dev *dev,
 968                             const struct input_device_id *id)
 969 {
 970         struct mousedev *mousedev;
 971         int error;
 972
 973         mousedev = mousedev_create(dev, handler, false);
 974         if (IS_ERR(mousedev))
 975                 return PTR_ERR(mousedev);
 976
 977         error = mixdev_add_device(mousedev);
 978         if (error) {
 979                 mousedev_destroy(mousedev);
 980                 return error;
 981         }
 982
 983         return 0;
 984 }
 985
 986 static void mousedev_disconnect(struct input_handle *handle)
 987 {
 988         struct mousedev *mousedev = handle->private;
 989
 990         mixdev_remove_device(mousedev);
 991         mousedev_destroy(mousedev);
 992 }
 993
 994 static const struct input_device_id mousedev_ids[] = {
 995         {
 996                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 997                                 INPUT_DEVICE_ID_MATCH_KEYBIT |
 998                                 INPUT_DEVICE_ID_MATCH_RELBIT,
 999                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_REL) },
1000                 .keybit = { [BIT_WORD(BTN_LEFT)] = BIT_MASK(BTN_LEFT) },
1001                 .relbit = { BIT_MASK(REL_X) | BIT_MASK(REL_Y) },
1002         },      /* A mouse like device, at least one button,
1003                    two relative axes */
1004         {
1005                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1006                                 INPUT_DEVICE_ID_MATCH_RELBIT,
1007                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_REL) },
1008                 .relbit = { BIT_MASK(REL_WHEEL) },
1009         },      /* A separate scrollwheel */
1010         {
1011                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1012                                 INPUT_DEVICE_ID_MATCH_KEYBIT |
1013                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
1014                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS) },
1015                 .keybit = { [BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH) },
1016                 .absbit = { BIT_MASK(ABS_X) | BIT_MASK(ABS_Y) },
1017         },      /* A tablet like device, at least touch detection,
1018                    two absolute axes */
1019         {
1020                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1021                                 INPUT_DEVICE_ID_MATCH_KEYBIT |
1022                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
1023                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS) },
1024                 .keybit = { [BIT_WORD(BTN_TOOL_FINGER)] =
1025                                 BIT_MASK(BTN_TOOL_FINGER) },
1026                 .absbit = { BIT_MASK(ABS_X) | BIT_MASK(ABS_Y) |
1027                                 BIT_MASK(ABS_PRESSURE) |
1028                                 BIT_MASK(ABS_TOOL_WIDTH) },
1029         },      /* A touchpad */
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_LEFT)] = BIT_MASK(BTN_LEFT) },
1036                 .absbit = { BIT_MASK(ABS_X) | BIT_MASK(ABS_Y) },
1037         },      /* Mouse-like device with absolute X and Y but ordinary
1038                    clicks, like hp ILO2 High Performance mouse */
1039
1040         { },    /* Terminating entry */
1041 };
1042
1043 MODULE_DEVICE_TABLE(input, mousedev_ids);
1044
1045 static struct input_handler mousedev_handler = {
1046         .event          = mousedev_event,
1047         .connect        = mousedev_connect,
1048         .disconnect     = mousedev_disconnect,
1049         .legacy_minors  = true,
1050         .minor          = MOUSEDEV_MINOR_BASE,
1051         .name           = "mousedev",
1052         .id_table       = mousedev_ids,
1053 };
1054
1055 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
1056 #include <linux/miscdevice.h>
1057
1058 static struct miscdevice psaux_mouse = {
1059         .minor  = PSMOUSE_MINOR,
1060         .name   = "psaux",
1061         .fops   = &mousedev_fops,
1062 };
1063
1064 static bool psaux_registered;
1065
1066 static void __init mousedev_psaux_register(void)
1067 {
1068         int error;
1069
1070         error = misc_register(&psaux_mouse);
1071         if (error)
1072                 pr_warn("could not register psaux device, error: %d\n",
1073                            error);
1074         else
1075                 psaux_registered = true;
1076 }
1077
1078 static void __exit mousedev_psaux_unregister(void)
1079 {
1080         if (psaux_registered)
1081                 misc_deregister(&psaux_mouse);
1082 }
1083 #else
1084 static inline void mousedev_psaux_register(void) { }
1085 static inline void mousedev_psaux_unregister(void) { }
1086 #endif
1087
1088 static int __init mousedev_init(void)
1089 {
1090         int error;
1091
1092         mousedev_mix = mousedev_create(NULL, &mousedev_handler, true);
1093         if (IS_ERR(mousedev_mix))
1094                 return PTR_ERR(mousedev_mix);
1095
1096         error = input_register_handler(&mousedev_handler);
1097         if (error) {
1098                 mousedev_destroy(mousedev_mix);
1099                 return error;
1100         }
1101
1102         mousedev_psaux_register();
1103
1104         pr_info("PS/2 mouse device common for all mice\n");
1105
1106         return 0;
1107 }
1108
1109 static void __exit mousedev_exit(void)
1110 {
1111         mousedev_psaux_unregister();
1112         input_unregister_handler(&mousedev_handler);
1113         mousedev_destroy(mousedev_mix);
1114 }
1115
1116 module_init(mousedev_init);
1117 module_exit(mousedev_exit);