1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Input driver to ExplorerPS/2 device driver module. 4 * 5 * Copyright (c) 1999-2002 Vojtech Pavlik 6 * Copyright (c) 2004 Dmitry Torokhov 7 */ 8 9 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 10 11 #define MOUSEDEV_MINOR_BASE 32 12 #define MOUSEDEV_MINORS 31 13 #define MOUSEDEV_MIX 63 14 15 #include <linux/bitops.h> 16 #include <linux/sched.h> 17 #include <linux/slab.h> 18 #include <linux/poll.h> 19 #include <linux/module.h> 20 #include <linux/init.h> 21 #include <linux/input.h> 22 #include <linux/random.h> 23 #include <linux/major.h> 24 #include <linux/device.h> 25 #include <linux/cdev.h> 26 #include <linux/kernel.h> 27 28 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>"); 29 MODULE_DESCRIPTION("Mouse (ExplorerPS/2) device interfaces"); 30 MODULE_LICENSE("GPL"); 31 32 #ifndef CONFIG_INPUT_MOUSEDEV_SCREEN_X 33 #define CONFIG_INPUT_MOUSEDEV_SCREEN_X 1024 34 #endif 35 #ifndef CONFIG_INPUT_MOUSEDEV_SCREEN_Y 36 #define CONFIG_INPUT_MOUSEDEV_SCREEN_Y 768 37 #endif 38 39 static int xres = CONFIG_INPUT_MOUSEDEV_SCREEN_X; 40 module_param(xres, uint, 0644); 41 MODULE_PARM_DESC(xres, "Horizontal screen resolution"); 42 43 static int yres = CONFIG_INPUT_MOUSEDEV_SCREEN_Y; 44 module_param(yres, uint, 0644); 45 MODULE_PARM_DESC(yres, "Vertical screen resolution"); 46 47 static unsigned tap_time = 200; 48 module_param(tap_time, uint, 0644); 49 MODULE_PARM_DESC(tap_time, "Tap time for touchpads in absolute mode (msecs)"); 50 51 struct mousedev_hw_data { 52 int dx, dy, dz; 53 int x, y; 54 int abs_event; 55 unsigned long buttons; 56 }; 57 58 struct mousedev { 59 int open; 60 struct input_handle handle; 61 wait_queue_head_t wait; 62 struct list_head client_list; 63 spinlock_t client_lock; /* protects client_list */ 64 struct mutex mutex; 65 struct device dev; 66 struct cdev cdev; 67 bool exist; 68 69 struct list_head mixdev_node; 70 bool opened_by_mixdev; 71 72 struct mousedev_hw_data packet; 73 unsigned int pkt_count; 74 int old_x[4], old_y[4]; 75 int frac_dx, frac_dy; 76 unsigned long touch; 77 78 int (*open_device)(struct mousedev *mousedev); 79 void (*close_device)(struct mousedev *mousedev); 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 u8 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 #define fx(i) (mousedev->old_x[(mousedev->pkt_count - (i)) & 03]) 120 #define fy(i) (mousedev->old_y[(mousedev->pkt_count - (i)) & 03]) 121 122 static void mousedev_touchpad_event(struct input_dev *dev, 123 struct mousedev *mousedev, 124 unsigned int code, int value) 125 { 126 int size, tmp; 127 enum { FRACTION_DENOM = 128 }; 128 129 switch (code) { 130 131 case ABS_X: 132 133 fx(0) = value; 134 if (mousedev->touch && mousedev->pkt_count >= 2) { 135 size = input_abs_get_max(dev, ABS_X) - 136 input_abs_get_min(dev, ABS_X); 137 if (size == 0) 138 size = 256 * 2; 139 140 tmp = ((value - fx(2)) * 256 * FRACTION_DENOM) / size; 141 tmp += mousedev->frac_dx; 142 mousedev->packet.dx = tmp / FRACTION_DENOM; 143 mousedev->frac_dx = 144 tmp - mousedev->packet.dx * FRACTION_DENOM; 145 } 146 break; 147 148 case ABS_Y: 149 fy(0) = value; 150 if (mousedev->touch && mousedev->pkt_count >= 2) { 151 /* use X size for ABS_Y to keep the same scale */ 152 size = input_abs_get_max(dev, ABS_X) - 153 input_abs_get_min(dev, ABS_X); 154 if (size == 0) 155 size = 256 * 2; 156 157 tmp = -((value - fy(2)) * 256 * FRACTION_DENOM) / size; 158 tmp += mousedev->frac_dy; 159 mousedev->packet.dy = tmp / FRACTION_DENOM; 160 mousedev->frac_dy = tmp - 161 mousedev->packet.dy * FRACTION_DENOM; 162 } 163 break; 164 } 165 } 166 167 static void mousedev_abs_event(struct input_dev *dev, struct mousedev *mousedev, 168 unsigned int code, int value) 169 { 170 int min, max, size; 171 172 switch (code) { 173 174 case ABS_X: 175 min = input_abs_get_min(dev, ABS_X); 176 max = input_abs_get_max(dev, ABS_X); 177 178 size = max - min; 179 if (size == 0) 180 size = xres ? : 1; 181 182 value = clamp(value, min, max); 183 184 mousedev->packet.x = ((value - min) * xres) / size; 185 mousedev->packet.abs_event = 1; 186 break; 187 188 case ABS_Y: 189 min = input_abs_get_min(dev, ABS_Y); 190 max = input_abs_get_max(dev, ABS_Y); 191 192 size = max - min; 193 if (size == 0) 194 size = yres ? : 1; 195 196 value = clamp(value, min, max); 197 198 mousedev->packet.y = yres - ((value - min) * yres) / size; 199 mousedev->packet.abs_event = 1; 200 break; 201 } 202 } 203 204 static void mousedev_rel_event(struct mousedev *mousedev, 205 unsigned int code, int value) 206 { 207 switch (code) { 208 case REL_X: 209 mousedev->packet.dx += value; 210 break; 211 212 case REL_Y: 213 mousedev->packet.dy -= value; 214 break; 215 216 case REL_WHEEL: 217 mousedev->packet.dz -= value; 218 break; 219 } 220 } 221 222 static void mousedev_key_event(struct mousedev *mousedev, 223 unsigned int code, int value) 224 { 225 int index; 226 227 switch (code) { 228 229 case BTN_TOUCH: 230 case BTN_0: 231 case BTN_LEFT: index = 0; break; 232 233 case BTN_STYLUS: 234 case BTN_1: 235 case BTN_RIGHT: index = 1; break; 236 237 case BTN_2: 238 case BTN_FORWARD: 239 case BTN_STYLUS2: 240 case BTN_MIDDLE: index = 2; break; 241 242 case BTN_3: 243 case BTN_BACK: 244 case BTN_SIDE: index = 3; break; 245 246 case BTN_4: 247 case BTN_EXTRA: index = 4; break; 248 249 default: return; 250 } 251 252 if (value) { 253 set_bit(index, &mousedev->packet.buttons); 254 set_bit(index, &mousedev_mix->packet.buttons); 255 } else { 256 clear_bit(index, &mousedev->packet.buttons); 257 clear_bit(index, &mousedev_mix->packet.buttons); 258 } 259 } 260 261 static void mousedev_notify_readers(struct mousedev *mousedev, 262 struct mousedev_hw_data *packet) 263 { 264 struct mousedev_client *client; 265 struct mousedev_motion *p; 266 unsigned int new_head; 267 int wake_readers = 0; 268 269 rcu_read_lock(); 270 list_for_each_entry_rcu(client, &mousedev->client_list, node) { 271 272 /* Just acquire the lock, interrupts already disabled */ 273 spin_lock(&client->packet_lock); 274 275 p = &client->packets[client->head]; 276 if (client->ready && p->buttons != mousedev->packet.buttons) { 277 new_head = (client->head + 1) % PACKET_QUEUE_LEN; 278 if (new_head != client->tail) { 279 p = &client->packets[client->head = new_head]; 280 memset(p, 0, sizeof(struct mousedev_motion)); 281 } 282 } 283 284 if (packet->abs_event) { 285 p->dx += packet->x - client->pos_x; 286 p->dy += packet->y - client->pos_y; 287 client->pos_x = packet->x; 288 client->pos_y = packet->y; 289 } 290 291 client->pos_x += packet->dx; 292 client->pos_x = clamp_val(client->pos_x, 0, xres); 293 294 client->pos_y += packet->dy; 295 client->pos_y = clamp_val(client->pos_y, 0, yres); 296 297 p->dx += packet->dx; 298 p->dy += packet->dy; 299 p->dz += packet->dz; 300 p->buttons = mousedev->packet.buttons; 301 302 if (p->dx || p->dy || p->dz || 303 p->buttons != client->last_buttons) 304 client->ready = 1; 305 306 spin_unlock(&client->packet_lock); 307 308 if (client->ready) { 309 kill_fasync(&client->fasync, SIGIO, POLL_IN); 310 wake_readers = 1; 311 } 312 } 313 rcu_read_unlock(); 314 315 if (wake_readers) 316 wake_up_interruptible(&mousedev->wait); 317 } 318 319 static void mousedev_touchpad_touch(struct mousedev *mousedev, int value) 320 { 321 if (!value) { 322 if (mousedev->touch && 323 time_before(jiffies, 324 mousedev->touch + msecs_to_jiffies(tap_time))) { 325 /* 326 * Toggle left button to emulate tap. 327 * We rely on the fact that mousedev_mix always has 0 328 * motion packet so we won't mess current position. 329 */ 330 set_bit(0, &mousedev->packet.buttons); 331 set_bit(0, &mousedev_mix->packet.buttons); 332 mousedev_notify_readers(mousedev, &mousedev_mix->packet); 333 mousedev_notify_readers(mousedev_mix, 334 &mousedev_mix->packet); 335 clear_bit(0, &mousedev->packet.buttons); 336 clear_bit(0, &mousedev_mix->packet.buttons); 337 } 338 mousedev->touch = mousedev->pkt_count = 0; 339 mousedev->frac_dx = 0; 340 mousedev->frac_dy = 0; 341 342 } else if (!mousedev->touch) 343 mousedev->touch = jiffies; 344 } 345 346 static void mousedev_event(struct input_handle *handle, 347 unsigned int type, unsigned int code, int value) 348 { 349 struct mousedev *mousedev = handle->private; 350 351 switch (type) { 352 353 case EV_ABS: 354 /* Ignore joysticks */ 355 if (test_bit(BTN_TRIGGER, handle->dev->keybit)) 356 return; 357 358 if (test_bit(BTN_TOOL_FINGER, handle->dev->keybit)) 359 mousedev_touchpad_event(handle->dev, 360 mousedev, code, value); 361 else 362 mousedev_abs_event(handle->dev, mousedev, code, value); 363 364 break; 365 366 case EV_REL: 367 mousedev_rel_event(mousedev, code, value); 368 break; 369 370 case EV_KEY: 371 if (value != 2) { 372 if (code == BTN_TOUCH && 373 test_bit(BTN_TOOL_FINGER, handle->dev->keybit)) 374 mousedev_touchpad_touch(mousedev, value); 375 else 376 mousedev_key_event(mousedev, code, value); 377 } 378 break; 379 380 case EV_SYN: 381 if (code == SYN_REPORT) { 382 if (mousedev->touch) { 383 mousedev->pkt_count++; 384 /* 385 * Input system eats duplicate events, 386 * but we need all of them to do correct 387 * averaging so apply present one forward 388 */ 389 fx(0) = fx(1); 390 fy(0) = fy(1); 391 } 392 393 mousedev_notify_readers(mousedev, &mousedev->packet); 394 mousedev_notify_readers(mousedev_mix, &mousedev->packet); 395 396 mousedev->packet.dx = mousedev->packet.dy = 397 mousedev->packet.dz = 0; 398 mousedev->packet.abs_event = 0; 399 } 400 break; 401 } 402 } 403 404 static int mousedev_fasync(int fd, struct file *file, int on) 405 { 406 struct mousedev_client *client = file->private_data; 407 408 return fasync_helper(fd, file, on, &client->fasync); 409 } 410 411 static void mousedev_free(struct device *dev) 412 { 413 struct mousedev *mousedev = container_of(dev, struct mousedev, dev); 414 415 input_put_device(mousedev->handle.dev); 416 kfree(mousedev); 417 } 418 419 static int mousedev_open_device(struct mousedev *mousedev) 420 { 421 int retval; 422 423 retval = mutex_lock_interruptible(&mousedev->mutex); 424 if (retval) 425 return retval; 426 427 if (!mousedev->exist) 428 retval = -ENODEV; 429 else if (!mousedev->open++) { 430 retval = input_open_device(&mousedev->handle); 431 if (retval) 432 mousedev->open--; 433 } 434 435 mutex_unlock(&mousedev->mutex); 436 return retval; 437 } 438 439 static void mousedev_close_device(struct mousedev *mousedev) 440 { 441 mutex_lock(&mousedev->mutex); 442 443 if (mousedev->exist && !--mousedev->open) 444 input_close_device(&mousedev->handle); 445 446 mutex_unlock(&mousedev->mutex); 447 } 448 449 /* 450 * Open all available devices so they can all be multiplexed in one. 451 * stream. Note that this function is called with mousedev_mix->mutex 452 * held. 453 */ 454 static int mixdev_open_devices(struct mousedev *mixdev) 455 { 456 int error; 457 458 error = mutex_lock_interruptible(&mixdev->mutex); 459 if (error) 460 return error; 461 462 if (!mixdev->open++) { 463 struct mousedev *mousedev; 464 465 list_for_each_entry(mousedev, &mousedev_mix_list, mixdev_node) { 466 if (!mousedev->opened_by_mixdev) { 467 if (mousedev_open_device(mousedev)) 468 continue; 469 470 mousedev->opened_by_mixdev = true; 471 } 472 } 473 } 474 475 mutex_unlock(&mixdev->mutex); 476 return 0; 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(struct mousedev *mixdev) 485 { 486 mutex_lock(&mixdev->mutex); 487 488 if (!--mixdev->open) { 489 struct mousedev *mousedev; 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 mutex_unlock(&mixdev->mutex); 500 } 501 502 503 static void mousedev_attach_client(struct mousedev *mousedev, 504 struct mousedev_client *client) 505 { 506 spin_lock(&mousedev->client_lock); 507 list_add_tail_rcu(&client->node, &mousedev->client_list); 508 spin_unlock(&mousedev->client_lock); 509 } 510 511 static void mousedev_detach_client(struct mousedev *mousedev, 512 struct mousedev_client *client) 513 { 514 spin_lock(&mousedev->client_lock); 515 list_del_rcu(&client->node); 516 spin_unlock(&mousedev->client_lock); 517 synchronize_rcu(); 518 } 519 520 static int mousedev_release(struct inode *inode, struct file *file) 521 { 522 struct mousedev_client *client = file->private_data; 523 struct mousedev *mousedev = client->mousedev; 524 525 mousedev_detach_client(mousedev, client); 526 kfree(client); 527 528 mousedev->close_device(mousedev); 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; 538 539 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX 540 if (imajor(inode) == MISC_MAJOR) 541 mousedev = mousedev_mix; 542 else 543 #endif 544 mousedev = container_of(inode->i_cdev, struct mousedev, cdev); 545 546 client = kzalloc(sizeof(struct mousedev_client), GFP_KERNEL); 547 if (!client) 548 return -ENOMEM; 549 550 spin_lock_init(&client->packet_lock); 551 client->pos_x = xres / 2; 552 client->pos_y = yres / 2; 553 client->mousedev = mousedev; 554 mousedev_attach_client(mousedev, client); 555 556 error = mousedev->open_device(mousedev); 557 if (error) 558 goto err_free_client; 559 560 file->private_data = client; 561 stream_open(inode, file); 562 563 return 0; 564 565 err_free_client: 566 mousedev_detach_client(mousedev, client); 567 kfree(client); 568 return error; 569 } 570 571 static void mousedev_packet(struct mousedev_client *client, u8 *ps2_data) 572 { 573 struct mousedev_motion *p = &client->packets[client->tail]; 574 s8 dx, dy, dz; 575 576 dx = clamp_val(p->dx, -127, 127); 577 p->dx -= dx; 578 579 dy = clamp_val(p->dy, -127, 127); 580 p->dy -= dy; 581 582 ps2_data[0] = BIT(3); 583 ps2_data[0] |= ((dx & BIT(7)) >> 3) | ((dy & BIT(7)) >> 2); 584 ps2_data[0] |= p->buttons & 0x07; 585 ps2_data[1] = dx; 586 ps2_data[2] = dy; 587 588 switch (client->mode) { 589 case MOUSEDEV_EMUL_EXPS: 590 dz = clamp_val(p->dz, -7, 7); 591 p->dz -= dz; 592 593 ps2_data[3] = (dz & 0x0f) | ((p->buttons & 0x18) << 1); 594 client->bufsiz = 4; 595 break; 596 597 case MOUSEDEV_EMUL_IMPS: 598 dz = clamp_val(p->dz, -127, 127); 599 p->dz -= dz; 600 601 ps2_data[0] |= ((p->buttons & 0x10) >> 3) | 602 ((p->buttons & 0x08) >> 1); 603 ps2_data[3] = dz; 604 605 client->bufsiz = 4; 606 break; 607 608 case MOUSEDEV_EMUL_PS2: 609 default: 610 p->dz = 0; 611 612 ps2_data[0] |= ((p->buttons & 0x10) >> 3) | 613 ((p->buttons & 0x08) >> 1); 614 615 client->bufsiz = 3; 616 break; 617 } 618 619 if (!p->dx && !p->dy && !p->dz) { 620 if (client->tail == client->head) { 621 client->ready = 0; 622 client->last_buttons = p->buttons; 623 } else 624 client->tail = (client->tail + 1) % PACKET_QUEUE_LEN; 625 } 626 } 627 628 static void mousedev_generate_response(struct mousedev_client *client, 629 int command) 630 { 631 client->ps2[0] = 0xfa; /* ACK */ 632 633 switch (command) { 634 635 case 0xeb: /* Poll */ 636 mousedev_packet(client, &client->ps2[1]); 637 client->bufsiz++; /* account for leading ACK */ 638 break; 639 640 case 0xf2: /* Get ID */ 641 switch (client->mode) { 642 case MOUSEDEV_EMUL_PS2: 643 client->ps2[1] = 0; 644 break; 645 case MOUSEDEV_EMUL_IMPS: 646 client->ps2[1] = 3; 647 break; 648 case MOUSEDEV_EMUL_EXPS: 649 client->ps2[1] = 4; 650 break; 651 } 652 client->bufsiz = 2; 653 break; 654 655 case 0xe9: /* Get info */ 656 client->ps2[1] = 0x60; client->ps2[2] = 3; client->ps2[3] = 200; 657 client->bufsiz = 4; 658 break; 659 660 case 0xff: /* Reset */ 661 client->impsseq = client->imexseq = 0; 662 client->mode = MOUSEDEV_EMUL_PS2; 663 client->ps2[1] = 0xaa; client->ps2[2] = 0x00; 664 client->bufsiz = 3; 665 break; 666 667 default: 668 client->bufsiz = 1; 669 break; 670 } 671 client->buffer = client->bufsiz; 672 } 673 674 static ssize_t mousedev_write(struct file *file, const char __user *buffer, 675 size_t count, loff_t *ppos) 676 { 677 struct mousedev_client *client = file->private_data; 678 unsigned char c; 679 unsigned int i; 680 681 for (i = 0; i < count; i++) { 682 683 if (get_user(c, buffer + i)) 684 return -EFAULT; 685 686 spin_lock_irq(&client->packet_lock); 687 688 if (c == mousedev_imex_seq[client->imexseq]) { 689 if (++client->imexseq == MOUSEDEV_SEQ_LEN) { 690 client->imexseq = 0; 691 client->mode = MOUSEDEV_EMUL_EXPS; 692 } 693 } else 694 client->imexseq = 0; 695 696 if (c == mousedev_imps_seq[client->impsseq]) { 697 if (++client->impsseq == MOUSEDEV_SEQ_LEN) { 698 client->impsseq = 0; 699 client->mode = MOUSEDEV_EMUL_IMPS; 700 } 701 } else 702 client->impsseq = 0; 703 704 mousedev_generate_response(client, c); 705 706 spin_unlock_irq(&client->packet_lock); 707 cond_resched(); 708 } 709 710 kill_fasync(&client->fasync, SIGIO, POLL_IN); 711 wake_up_interruptible(&client->mousedev->wait); 712 713 return count; 714 } 715 716 static ssize_t mousedev_read(struct file *file, char __user *buffer, 717 size_t count, loff_t *ppos) 718 { 719 struct mousedev_client *client = file->private_data; 720 struct mousedev *mousedev = client->mousedev; 721 u8 data[sizeof(client->ps2)]; 722 int retval = 0; 723 724 if (!client->ready && !client->buffer && mousedev->exist && 725 (file->f_flags & O_NONBLOCK)) 726 return -EAGAIN; 727 728 retval = wait_event_interruptible(mousedev->wait, 729 !mousedev->exist || client->ready || client->buffer); 730 if (retval) 731 return retval; 732 733 if (!mousedev->exist) 734 return -ENODEV; 735 736 spin_lock_irq(&client->packet_lock); 737 738 if (!client->buffer && client->ready) { 739 mousedev_packet(client, client->ps2); 740 client->buffer = client->bufsiz; 741 } 742 743 if (count > client->buffer) 744 count = client->buffer; 745 746 memcpy(data, client->ps2 + client->bufsiz - client->buffer, count); 747 client->buffer -= count; 748 749 spin_unlock_irq(&client->packet_lock); 750 751 if (copy_to_user(buffer, data, count)) 752 return -EFAULT; 753 754 return count; 755 } 756 757 /* No kernel lock - fine */ 758 static __poll_t mousedev_poll(struct file *file, poll_table *wait) 759 { 760 struct mousedev_client *client = file->private_data; 761 struct mousedev *mousedev = client->mousedev; 762 __poll_t mask; 763 764 poll_wait(file, &mousedev->wait, wait); 765 766 mask = mousedev->exist ? EPOLLOUT | EPOLLWRNORM : EPOLLHUP | EPOLLERR; 767 if (client->ready || client->buffer) 768 mask |= EPOLLIN | EPOLLRDNORM; 769 770 return mask; 771 } 772 773 static const struct file_operations mousedev_fops = { 774 .owner = THIS_MODULE, 775 .read = mousedev_read, 776 .write = mousedev_write, 777 .poll = mousedev_poll, 778 .open = mousedev_open, 779 .release = mousedev_release, 780 .fasync = mousedev_fasync, 781 .llseek = noop_llseek, 782 }; 783 784 /* 785 * Mark device non-existent. This disables writes, ioctls and 786 * prevents new users from opening the device. Already posted 787 * blocking reads will stay, however new ones will fail. 788 */ 789 static void mousedev_mark_dead(struct mousedev *mousedev) 790 { 791 mutex_lock(&mousedev->mutex); 792 mousedev->exist = false; 793 mutex_unlock(&mousedev->mutex); 794 } 795 796 /* 797 * Wake up users waiting for IO so they can disconnect from 798 * dead device. 799 */ 800 static void mousedev_hangup(struct mousedev *mousedev) 801 { 802 struct mousedev_client *client; 803 804 spin_lock(&mousedev->client_lock); 805 list_for_each_entry(client, &mousedev->client_list, node) 806 kill_fasync(&client->fasync, SIGIO, POLL_HUP); 807 spin_unlock(&mousedev->client_lock); 808 809 wake_up_interruptible(&mousedev->wait); 810 } 811 812 static void mousedev_cleanup(struct mousedev *mousedev) 813 { 814 struct input_handle *handle = &mousedev->handle; 815 816 mousedev_mark_dead(mousedev); 817 mousedev_hangup(mousedev); 818 819 /* mousedev is marked dead so no one else accesses mousedev->open */ 820 if (mousedev->open) 821 input_close_device(handle); 822 } 823 824 static int mousedev_reserve_minor(bool mixdev) 825 { 826 int minor; 827 828 if (mixdev) { 829 minor = input_get_new_minor(MOUSEDEV_MIX, 1, false); 830 if (minor < 0) 831 pr_err("failed to reserve mixdev minor: %d\n", minor); 832 } else { 833 minor = input_get_new_minor(MOUSEDEV_MINOR_BASE, 834 MOUSEDEV_MINORS, true); 835 if (minor < 0) 836 pr_err("failed to reserve new minor: %d\n", minor); 837 } 838 839 return minor; 840 } 841 842 static struct mousedev *mousedev_create(struct input_dev *dev, 843 struct input_handler *handler, 844 bool mixdev) 845 { 846 struct mousedev *mousedev; 847 int minor; 848 int error; 849 850 minor = mousedev_reserve_minor(mixdev); 851 if (minor < 0) { 852 error = minor; 853 goto err_out; 854 } 855 856 mousedev = kzalloc(sizeof(struct mousedev), GFP_KERNEL); 857 if (!mousedev) { 858 error = -ENOMEM; 859 goto err_free_minor; 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 mixdev ? SINGLE_DEPTH_NESTING : 0); 868 init_waitqueue_head(&mousedev->wait); 869 870 if (mixdev) { 871 dev_set_name(&mousedev->dev, "mice"); 872 873 mousedev->open_device = mixdev_open_devices; 874 mousedev->close_device = mixdev_close_devices; 875 } else { 876 int dev_no = minor; 877 /* Normalize device number if it falls into legacy range */ 878 if (dev_no < MOUSEDEV_MINOR_BASE + MOUSEDEV_MINORS) 879 dev_no -= MOUSEDEV_MINOR_BASE; 880 dev_set_name(&mousedev->dev, "mouse%d", dev_no); 881 882 mousedev->open_device = mousedev_open_device; 883 mousedev->close_device = mousedev_close_device; 884 } 885 886 mousedev->exist = true; 887 mousedev->handle.dev = input_get_device(dev); 888 mousedev->handle.name = dev_name(&mousedev->dev); 889 mousedev->handle.handler = handler; 890 mousedev->handle.private = mousedev; 891 892 mousedev->dev.class = &input_class; 893 if (dev) 894 mousedev->dev.parent = &dev->dev; 895 mousedev->dev.devt = MKDEV(INPUT_MAJOR, minor); 896 mousedev->dev.release = mousedev_free; 897 device_initialize(&mousedev->dev); 898 899 if (!mixdev) { 900 error = input_register_handle(&mousedev->handle); 901 if (error) 902 goto err_free_mousedev; 903 } 904 905 cdev_init(&mousedev->cdev, &mousedev_fops); 906 907 error = cdev_device_add(&mousedev->cdev, &mousedev->dev); 908 if (error) 909 goto err_cleanup_mousedev; 910 911 return mousedev; 912 913 err_cleanup_mousedev: 914 mousedev_cleanup(mousedev); 915 if (!mixdev) 916 input_unregister_handle(&mousedev->handle); 917 err_free_mousedev: 918 put_device(&mousedev->dev); 919 err_free_minor: 920 input_free_minor(minor); 921 err_out: 922 return ERR_PTR(error); 923 } 924 925 static void mousedev_destroy(struct mousedev *mousedev) 926 { 927 cdev_device_del(&mousedev->cdev, &mousedev->dev); 928 mousedev_cleanup(mousedev); 929 input_free_minor(MINOR(mousedev->dev.devt)); 930 if (mousedev != mousedev_mix) 931 input_unregister_handle(&mousedev->handle); 932 put_device(&mousedev->dev); 933 } 934 935 static int mixdev_add_device(struct mousedev *mousedev) 936 { 937 int retval; 938 939 retval = mutex_lock_interruptible(&mousedev_mix->mutex); 940 if (retval) 941 return retval; 942 943 if (mousedev_mix->open) { 944 retval = mousedev_open_device(mousedev); 945 if (retval) 946 goto out; 947 948 mousedev->opened_by_mixdev = true; 949 } 950 951 get_device(&mousedev->dev); 952 list_add_tail(&mousedev->mixdev_node, &mousedev_mix_list); 953 954 out: 955 mutex_unlock(&mousedev_mix->mutex); 956 return retval; 957 } 958 959 static void mixdev_remove_device(struct mousedev *mousedev) 960 { 961 mutex_lock(&mousedev_mix->mutex); 962 963 if (mousedev->opened_by_mixdev) { 964 mousedev->opened_by_mixdev = false; 965 mousedev_close_device(mousedev); 966 } 967 968 list_del_init(&mousedev->mixdev_node); 969 mutex_unlock(&mousedev_mix->mutex); 970 971 put_device(&mousedev->dev); 972 } 973 974 static int mousedev_connect(struct input_handler *handler, 975 struct input_dev *dev, 976 const struct input_device_id *id) 977 { 978 struct mousedev *mousedev; 979 int error; 980 981 mousedev = mousedev_create(dev, handler, false); 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 .legacy_minors = true, 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, true); 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); 1126