1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Device driver for the Apple Desktop Bus 4 * and the /dev/adb device on macintoshes. 5 * 6 * Copyright (C) 1996 Paul Mackerras. 7 * 8 * Modified to declare controllers as structures, added 9 * client notification of bus reset and handles PowerBook 10 * sleep, by Benjamin Herrenschmidt. 11 * 12 * To do: 13 * 14 * - /sys/bus/adb to list the devices and infos 15 * - more /dev/adb to allow userland to receive the 16 * flow of auto-polling datas from a given device. 17 * - move bus probe to a kernel thread 18 */ 19 20 #include <linux/types.h> 21 #include <linux/errno.h> 22 #include <linux/kernel.h> 23 #include <linux/slab.h> 24 #include <linux/module.h> 25 #include <linux/fs.h> 26 #include <linux/mm.h> 27 #include <linux/sched/signal.h> 28 #include <linux/adb.h> 29 #include <linux/cuda.h> 30 #include <linux/pmu.h> 31 #include <linux/notifier.h> 32 #include <linux/wait.h> 33 #include <linux/init.h> 34 #include <linux/delay.h> 35 #include <linux/spinlock.h> 36 #include <linux/completion.h> 37 #include <linux/device.h> 38 #include <linux/kthread.h> 39 #include <linux/platform_device.h> 40 #include <linux/mutex.h> 41 #include <linux/of.h> 42 43 #include <linux/uaccess.h> 44 #ifdef CONFIG_PPC 45 #include <asm/machdep.h> 46 #endif 47 48 49 EXPORT_SYMBOL(adb_client_list); 50 51 extern struct adb_driver via_macii_driver; 52 extern struct adb_driver via_cuda_driver; 53 extern struct adb_driver adb_iop_driver; 54 extern struct adb_driver via_pmu_driver; 55 extern struct adb_driver macio_adb_driver; 56 57 static DEFINE_MUTEX(adb_mutex); 58 static struct adb_driver *adb_driver_list[] = { 59 #ifdef CONFIG_ADB_MACII 60 &via_macii_driver, 61 #endif 62 #ifdef CONFIG_ADB_CUDA 63 &via_cuda_driver, 64 #endif 65 #ifdef CONFIG_ADB_IOP 66 &adb_iop_driver, 67 #endif 68 #ifdef CONFIG_ADB_PMU 69 &via_pmu_driver, 70 #endif 71 #ifdef CONFIG_ADB_MACIO 72 &macio_adb_driver, 73 #endif 74 NULL 75 }; 76 77 static struct class *adb_dev_class; 78 79 static struct adb_driver *adb_controller; 80 BLOCKING_NOTIFIER_HEAD(adb_client_list); 81 static int adb_got_sleep; 82 static int adb_inited; 83 static DEFINE_SEMAPHORE(adb_probe_mutex); 84 static int sleepy_trackpad; 85 static int autopoll_devs; 86 int __adb_probe_sync; 87 88 static int adb_scan_bus(void); 89 static int do_adb_reset_bus(void); 90 static void adbdev_init(void); 91 static int try_handler_change(int, int); 92 93 static struct adb_handler { 94 void (*handler)(unsigned char *, int, int); 95 int original_address; 96 int handler_id; 97 int busy; 98 } adb_handler[16]; 99 100 /* 101 * The adb_handler_mutex mutex protects all accesses to the original_address 102 * and handler_id fields of adb_handler[i] for all i, and changes to the 103 * handler field. 104 * Accesses to the handler field are protected by the adb_handler_lock 105 * rwlock. It is held across all calls to any handler, so that by the 106 * time adb_unregister returns, we know that the old handler isn't being 107 * called. 108 */ 109 static DEFINE_MUTEX(adb_handler_mutex); 110 static DEFINE_RWLOCK(adb_handler_lock); 111 112 #if 0 113 static void printADBreply(struct adb_request *req) 114 { 115 int i; 116 117 printk("adb reply (%d)", req->reply_len); 118 for(i = 0; i < req->reply_len; i++) 119 printk(" %x", req->reply[i]); 120 printk("\n"); 121 122 } 123 #endif 124 125 static int adb_scan_bus(void) 126 { 127 int i, highFree=0, noMovement; 128 int devmask = 0; 129 struct adb_request req; 130 131 /* assumes adb_handler[] is all zeroes at this point */ 132 for (i = 1; i < 16; i++) { 133 /* see if there is anything at address i */ 134 adb_request(&req, NULL, ADBREQ_SYNC | ADBREQ_REPLY, 1, 135 (i << 4) | 0xf); 136 if (req.reply_len > 1) 137 /* one or more devices at this address */ 138 adb_handler[i].original_address = i; 139 else if (i > highFree) 140 highFree = i; 141 } 142 143 /* Note we reset noMovement to 0 each time we move a device */ 144 for (noMovement = 1; noMovement < 2 && highFree > 0; noMovement++) { 145 for (i = 1; i < 16; i++) { 146 if (adb_handler[i].original_address == 0) 147 continue; 148 /* 149 * Send a "talk register 3" command to address i 150 * to provoke a collision if there is more than 151 * one device at this address. 152 */ 153 adb_request(&req, NULL, ADBREQ_SYNC | ADBREQ_REPLY, 1, 154 (i << 4) | 0xf); 155 /* 156 * Move the device(s) which didn't detect a 157 * collision to address `highFree'. Hopefully 158 * this only moves one device. 159 */ 160 adb_request(&req, NULL, ADBREQ_SYNC, 3, 161 (i<< 4) | 0xb, (highFree | 0x60), 0xfe); 162 /* 163 * See if anybody actually moved. This is suggested 164 * by HW TechNote 01: 165 * 166 * https://developer.apple.com/technotes/hw/hw_01.html 167 */ 168 adb_request(&req, NULL, ADBREQ_SYNC | ADBREQ_REPLY, 1, 169 (highFree << 4) | 0xf); 170 if (req.reply_len <= 1) continue; 171 /* 172 * Test whether there are any device(s) left 173 * at address i. 174 */ 175 adb_request(&req, NULL, ADBREQ_SYNC | ADBREQ_REPLY, 1, 176 (i << 4) | 0xf); 177 if (req.reply_len > 1) { 178 /* 179 * There are still one or more devices 180 * left at address i. Register the one(s) 181 * we moved to `highFree', and find a new 182 * value for highFree. 183 */ 184 adb_handler[highFree].original_address = 185 adb_handler[i].original_address; 186 while (highFree > 0 && 187 adb_handler[highFree].original_address) 188 highFree--; 189 if (highFree <= 0) 190 break; 191 192 noMovement = 0; 193 } else { 194 /* 195 * No devices left at address i; move the 196 * one(s) we moved to `highFree' back to i. 197 */ 198 adb_request(&req, NULL, ADBREQ_SYNC, 3, 199 (highFree << 4) | 0xb, 200 (i | 0x60), 0xfe); 201 } 202 } 203 } 204 205 /* Now fill in the handler_id field of the adb_handler entries. */ 206 for (i = 1; i < 16; i++) { 207 if (adb_handler[i].original_address == 0) 208 continue; 209 adb_request(&req, NULL, ADBREQ_SYNC | ADBREQ_REPLY, 1, 210 (i << 4) | 0xf); 211 adb_handler[i].handler_id = req.reply[2]; 212 printk(KERN_DEBUG "adb device [%d]: %d 0x%X\n", i, 213 adb_handler[i].original_address, 214 adb_handler[i].handler_id); 215 devmask |= 1 << i; 216 } 217 return devmask; 218 } 219 220 /* 221 * This kernel task handles ADB probing. It dies once probing is 222 * completed. 223 */ 224 static int 225 adb_probe_task(void *x) 226 { 227 pr_debug("adb: starting probe task...\n"); 228 do_adb_reset_bus(); 229 pr_debug("adb: finished probe task...\n"); 230 231 up(&adb_probe_mutex); 232 233 return 0; 234 } 235 236 static void 237 __adb_probe_task(struct work_struct *bullshit) 238 { 239 kthread_run(adb_probe_task, NULL, "kadbprobe"); 240 } 241 242 static DECLARE_WORK(adb_reset_work, __adb_probe_task); 243 244 int 245 adb_reset_bus(void) 246 { 247 if (__adb_probe_sync) { 248 do_adb_reset_bus(); 249 return 0; 250 } 251 252 down(&adb_probe_mutex); 253 schedule_work(&adb_reset_work); 254 return 0; 255 } 256 257 #ifdef CONFIG_PM 258 /* 259 * notify clients before sleep 260 */ 261 static int __adb_suspend(struct platform_device *dev, pm_message_t state) 262 { 263 adb_got_sleep = 1; 264 /* We need to get a lock on the probe thread */ 265 down(&adb_probe_mutex); 266 /* Stop autopoll */ 267 if (adb_controller->autopoll) 268 adb_controller->autopoll(0); 269 blocking_notifier_call_chain(&adb_client_list, ADB_MSG_POWERDOWN, NULL); 270 271 return 0; 272 } 273 274 static int adb_suspend(struct device *dev) 275 { 276 return __adb_suspend(to_platform_device(dev), PMSG_SUSPEND); 277 } 278 279 static int adb_freeze(struct device *dev) 280 { 281 return __adb_suspend(to_platform_device(dev), PMSG_FREEZE); 282 } 283 284 static int adb_poweroff(struct device *dev) 285 { 286 return __adb_suspend(to_platform_device(dev), PMSG_HIBERNATE); 287 } 288 289 /* 290 * reset bus after sleep 291 */ 292 static int __adb_resume(struct platform_device *dev) 293 { 294 adb_got_sleep = 0; 295 up(&adb_probe_mutex); 296 adb_reset_bus(); 297 298 return 0; 299 } 300 301 static int adb_resume(struct device *dev) 302 { 303 return __adb_resume(to_platform_device(dev)); 304 } 305 #endif /* CONFIG_PM */ 306 307 static int __init adb_init(void) 308 { 309 struct adb_driver *driver; 310 int i; 311 312 #ifdef CONFIG_PPC32 313 if (!machine_is(chrp) && !machine_is(powermac)) 314 return 0; 315 #endif 316 #ifdef CONFIG_MAC 317 if (!MACH_IS_MAC) 318 return 0; 319 #endif 320 321 /* xmon may do early-init */ 322 if (adb_inited) 323 return 0; 324 adb_inited = 1; 325 326 adb_controller = NULL; 327 328 i = 0; 329 while ((driver = adb_driver_list[i++]) != NULL) { 330 if (!driver->probe()) { 331 adb_controller = driver; 332 break; 333 } 334 } 335 if (adb_controller != NULL && adb_controller->init && 336 adb_controller->init()) 337 adb_controller = NULL; 338 if (adb_controller == NULL) { 339 pr_warn("Warning: no ADB interface detected\n"); 340 } else { 341 #ifdef CONFIG_PPC 342 if (of_machine_is_compatible("AAPL,PowerBook1998") || 343 of_machine_is_compatible("PowerBook1,1")) 344 sleepy_trackpad = 1; 345 #endif /* CONFIG_PPC */ 346 347 adbdev_init(); 348 adb_reset_bus(); 349 } 350 return 0; 351 } 352 353 device_initcall(adb_init); 354 355 static int 356 do_adb_reset_bus(void) 357 { 358 int ret; 359 360 if (adb_controller == NULL) 361 return -ENXIO; 362 363 if (adb_controller->autopoll) 364 adb_controller->autopoll(0); 365 366 blocking_notifier_call_chain(&adb_client_list, 367 ADB_MSG_PRE_RESET, NULL); 368 369 if (sleepy_trackpad) { 370 /* Let the trackpad settle down */ 371 msleep(500); 372 } 373 374 mutex_lock(&adb_handler_mutex); 375 write_lock_irq(&adb_handler_lock); 376 memset(adb_handler, 0, sizeof(adb_handler)); 377 write_unlock_irq(&adb_handler_lock); 378 379 /* That one is still a bit synchronous, oh well... */ 380 if (adb_controller->reset_bus) 381 ret = adb_controller->reset_bus(); 382 else 383 ret = 0; 384 385 if (sleepy_trackpad) { 386 /* Let the trackpad settle down */ 387 msleep(1500); 388 } 389 390 if (!ret) { 391 autopoll_devs = adb_scan_bus(); 392 if (adb_controller->autopoll) 393 adb_controller->autopoll(autopoll_devs); 394 } 395 mutex_unlock(&adb_handler_mutex); 396 397 blocking_notifier_call_chain(&adb_client_list, 398 ADB_MSG_POST_RESET, NULL); 399 400 return ret; 401 } 402 403 void 404 adb_poll(void) 405 { 406 if ((adb_controller == NULL)||(adb_controller->poll == NULL)) 407 return; 408 adb_controller->poll(); 409 } 410 EXPORT_SYMBOL(adb_poll); 411 412 static void adb_sync_req_done(struct adb_request *req) 413 { 414 struct completion *comp = req->arg; 415 416 complete(comp); 417 } 418 419 int 420 adb_request(struct adb_request *req, void (*done)(struct adb_request *), 421 int flags, int nbytes, ...) 422 { 423 va_list list; 424 int i; 425 int rc; 426 struct completion comp; 427 428 if ((adb_controller == NULL) || (adb_controller->send_request == NULL)) 429 return -ENXIO; 430 if (nbytes < 1) 431 return -EINVAL; 432 433 req->nbytes = nbytes+1; 434 req->done = done; 435 req->reply_expected = flags & ADBREQ_REPLY; 436 req->data[0] = ADB_PACKET; 437 va_start(list, nbytes); 438 for (i = 0; i < nbytes; ++i) 439 req->data[i+1] = va_arg(list, int); 440 va_end(list); 441 442 if (flags & ADBREQ_NOSEND) 443 return 0; 444 445 /* Synchronous requests block using an on-stack completion */ 446 if (flags & ADBREQ_SYNC) { 447 WARN_ON(done); 448 req->done = adb_sync_req_done; 449 req->arg = ∁ 450 init_completion(&comp); 451 } 452 453 rc = adb_controller->send_request(req, 0); 454 455 if ((flags & ADBREQ_SYNC) && !rc && !req->complete) 456 wait_for_completion(&comp); 457 458 return rc; 459 } 460 EXPORT_SYMBOL(adb_request); 461 462 /* Ultimately this should return the number of devices with 463 the given default id. 464 And it does it now ! Note: changed behaviour: This function 465 will now register if default_id _and_ handler_id both match 466 but handler_id can be left to 0 to match with default_id only. 467 When handler_id is set, this function will try to adjust 468 the handler_id id it doesn't match. */ 469 int 470 adb_register(int default_id, int handler_id, struct adb_ids *ids, 471 void (*handler)(unsigned char *, int, int)) 472 { 473 int i; 474 475 mutex_lock(&adb_handler_mutex); 476 ids->nids = 0; 477 for (i = 1; i < 16; i++) { 478 if ((adb_handler[i].original_address == default_id) && 479 (!handler_id || (handler_id == adb_handler[i].handler_id) || 480 try_handler_change(i, handler_id))) { 481 if (adb_handler[i].handler) { 482 pr_err("Two handlers for ADB device %d\n", 483 default_id); 484 continue; 485 } 486 write_lock_irq(&adb_handler_lock); 487 adb_handler[i].handler = handler; 488 write_unlock_irq(&adb_handler_lock); 489 ids->id[ids->nids++] = i; 490 } 491 } 492 mutex_unlock(&adb_handler_mutex); 493 return ids->nids; 494 } 495 EXPORT_SYMBOL(adb_register); 496 497 int 498 adb_unregister(int index) 499 { 500 int ret = -ENODEV; 501 502 mutex_lock(&adb_handler_mutex); 503 write_lock_irq(&adb_handler_lock); 504 if (adb_handler[index].handler) { 505 while(adb_handler[index].busy) { 506 write_unlock_irq(&adb_handler_lock); 507 yield(); 508 write_lock_irq(&adb_handler_lock); 509 } 510 ret = 0; 511 adb_handler[index].handler = NULL; 512 } 513 write_unlock_irq(&adb_handler_lock); 514 mutex_unlock(&adb_handler_mutex); 515 return ret; 516 } 517 EXPORT_SYMBOL(adb_unregister); 518 519 void 520 adb_input(unsigned char *buf, int nb, int autopoll) 521 { 522 int i, id; 523 static int dump_adb_input; 524 unsigned long flags; 525 526 void (*handler)(unsigned char *, int, int); 527 528 /* We skip keystrokes and mouse moves when the sleep process 529 * has been started. We stop autopoll, but this is another security 530 */ 531 if (adb_got_sleep) 532 return; 533 534 id = buf[0] >> 4; 535 if (dump_adb_input) { 536 pr_info("adb packet: "); 537 for (i = 0; i < nb; ++i) 538 pr_cont(" %x", buf[i]); 539 pr_cont(", id = %d\n", id); 540 } 541 write_lock_irqsave(&adb_handler_lock, flags); 542 handler = adb_handler[id].handler; 543 if (handler != NULL) 544 adb_handler[id].busy = 1; 545 write_unlock_irqrestore(&adb_handler_lock, flags); 546 if (handler != NULL) { 547 (*handler)(buf, nb, autopoll); 548 wmb(); 549 adb_handler[id].busy = 0; 550 } 551 552 } 553 554 /* Try to change handler to new_id. Will return 1 if successful. */ 555 static int try_handler_change(int address, int new_id) 556 { 557 struct adb_request req; 558 559 if (adb_handler[address].handler_id == new_id) 560 return 1; 561 adb_request(&req, NULL, ADBREQ_SYNC, 3, 562 ADB_WRITEREG(address, 3), address | 0x20, new_id); 563 adb_request(&req, NULL, ADBREQ_SYNC | ADBREQ_REPLY, 1, 564 ADB_READREG(address, 3)); 565 if (req.reply_len < 2) 566 return 0; 567 if (req.reply[2] != new_id) 568 return 0; 569 adb_handler[address].handler_id = req.reply[2]; 570 571 return 1; 572 } 573 574 int 575 adb_try_handler_change(int address, int new_id) 576 { 577 int ret; 578 579 mutex_lock(&adb_handler_mutex); 580 ret = try_handler_change(address, new_id); 581 mutex_unlock(&adb_handler_mutex); 582 if (ret) 583 pr_debug("adb handler change: [%d] 0x%X\n", address, new_id); 584 return ret; 585 } 586 EXPORT_SYMBOL(adb_try_handler_change); 587 588 int 589 adb_get_infos(int address, int *original_address, int *handler_id) 590 { 591 mutex_lock(&adb_handler_mutex); 592 *original_address = adb_handler[address].original_address; 593 *handler_id = adb_handler[address].handler_id; 594 mutex_unlock(&adb_handler_mutex); 595 596 return (*original_address != 0); 597 } 598 599 600 /* 601 * /dev/adb device driver. 602 */ 603 604 #define ADB_MAJOR 56 /* major number for /dev/adb */ 605 606 struct adbdev_state { 607 spinlock_t lock; 608 atomic_t n_pending; 609 struct adb_request *completed; 610 wait_queue_head_t wait_queue; 611 int inuse; 612 }; 613 614 static void adb_write_done(struct adb_request *req) 615 { 616 struct adbdev_state *state = (struct adbdev_state *) req->arg; 617 unsigned long flags; 618 619 if (!req->complete) { 620 req->reply_len = 0; 621 req->complete = 1; 622 } 623 spin_lock_irqsave(&state->lock, flags); 624 atomic_dec(&state->n_pending); 625 if (!state->inuse) { 626 kfree(req); 627 if (atomic_read(&state->n_pending) == 0) { 628 spin_unlock_irqrestore(&state->lock, flags); 629 kfree(state); 630 return; 631 } 632 } else { 633 struct adb_request **ap = &state->completed; 634 while (*ap != NULL) 635 ap = &(*ap)->next; 636 req->next = NULL; 637 *ap = req; 638 wake_up_interruptible(&state->wait_queue); 639 } 640 spin_unlock_irqrestore(&state->lock, flags); 641 } 642 643 static int 644 do_adb_query(struct adb_request *req) 645 { 646 int ret = -EINVAL; 647 648 switch(req->data[1]) { 649 case ADB_QUERY_GETDEVINFO: 650 if (req->nbytes < 3 || req->data[2] >= 16) 651 break; 652 mutex_lock(&adb_handler_mutex); 653 req->reply[0] = adb_handler[req->data[2]].original_address; 654 req->reply[1] = adb_handler[req->data[2]].handler_id; 655 mutex_unlock(&adb_handler_mutex); 656 req->complete = 1; 657 req->reply_len = 2; 658 adb_write_done(req); 659 ret = 0; 660 break; 661 } 662 return ret; 663 } 664 665 static int adb_open(struct inode *inode, struct file *file) 666 { 667 struct adbdev_state *state; 668 int ret = 0; 669 670 mutex_lock(&adb_mutex); 671 if (iminor(inode) > 0 || adb_controller == NULL) { 672 ret = -ENXIO; 673 goto out; 674 } 675 state = kmalloc(sizeof(struct adbdev_state), GFP_KERNEL); 676 if (!state) { 677 ret = -ENOMEM; 678 goto out; 679 } 680 file->private_data = state; 681 spin_lock_init(&state->lock); 682 atomic_set(&state->n_pending, 0); 683 state->completed = NULL; 684 init_waitqueue_head(&state->wait_queue); 685 state->inuse = 1; 686 687 out: 688 mutex_unlock(&adb_mutex); 689 return ret; 690 } 691 692 static int adb_release(struct inode *inode, struct file *file) 693 { 694 struct adbdev_state *state = file->private_data; 695 unsigned long flags; 696 697 mutex_lock(&adb_mutex); 698 if (state) { 699 file->private_data = NULL; 700 spin_lock_irqsave(&state->lock, flags); 701 if (atomic_read(&state->n_pending) == 0 702 && state->completed == NULL) { 703 spin_unlock_irqrestore(&state->lock, flags); 704 kfree(state); 705 } else { 706 state->inuse = 0; 707 spin_unlock_irqrestore(&state->lock, flags); 708 } 709 } 710 mutex_unlock(&adb_mutex); 711 return 0; 712 } 713 714 static ssize_t adb_read(struct file *file, char __user *buf, 715 size_t count, loff_t *ppos) 716 { 717 int ret = 0; 718 struct adbdev_state *state = file->private_data; 719 struct adb_request *req; 720 DECLARE_WAITQUEUE(wait, current); 721 unsigned long flags; 722 723 if (count < 2) 724 return -EINVAL; 725 if (count > sizeof(req->reply)) 726 count = sizeof(req->reply); 727 728 req = NULL; 729 spin_lock_irqsave(&state->lock, flags); 730 add_wait_queue(&state->wait_queue, &wait); 731 set_current_state(TASK_INTERRUPTIBLE); 732 733 for (;;) { 734 req = state->completed; 735 if (req != NULL) 736 state->completed = req->next; 737 else if (atomic_read(&state->n_pending) == 0) 738 ret = -EIO; 739 if (req != NULL || ret != 0) 740 break; 741 742 if (file->f_flags & O_NONBLOCK) { 743 ret = -EAGAIN; 744 break; 745 } 746 if (signal_pending(current)) { 747 ret = -ERESTARTSYS; 748 break; 749 } 750 spin_unlock_irqrestore(&state->lock, flags); 751 schedule(); 752 spin_lock_irqsave(&state->lock, flags); 753 } 754 755 set_current_state(TASK_RUNNING); 756 remove_wait_queue(&state->wait_queue, &wait); 757 spin_unlock_irqrestore(&state->lock, flags); 758 759 if (ret) 760 return ret; 761 762 ret = req->reply_len; 763 if (ret > count) 764 ret = count; 765 if (ret > 0 && copy_to_user(buf, req->reply, ret)) 766 ret = -EFAULT; 767 768 kfree(req); 769 return ret; 770 } 771 772 static ssize_t adb_write(struct file *file, const char __user *buf, 773 size_t count, loff_t *ppos) 774 { 775 int ret/*, i*/; 776 struct adbdev_state *state = file->private_data; 777 struct adb_request *req; 778 779 if (count < 2 || count > sizeof(req->data)) 780 return -EINVAL; 781 if (adb_controller == NULL) 782 return -ENXIO; 783 784 req = kmalloc(sizeof(struct adb_request), 785 GFP_KERNEL); 786 if (req == NULL) 787 return -ENOMEM; 788 789 req->nbytes = count; 790 req->done = adb_write_done; 791 req->arg = (void *) state; 792 req->complete = 0; 793 794 ret = -EFAULT; 795 if (copy_from_user(req->data, buf, count)) 796 goto out; 797 798 atomic_inc(&state->n_pending); 799 800 /* If a probe is in progress or we are sleeping, wait for it to complete */ 801 down(&adb_probe_mutex); 802 803 /* Queries are special requests sent to the ADB driver itself */ 804 if (req->data[0] == ADB_QUERY) { 805 if (count > 1) 806 ret = do_adb_query(req); 807 else 808 ret = -EINVAL; 809 up(&adb_probe_mutex); 810 } 811 /* Special case for ADB_BUSRESET request, all others are sent to 812 the controller */ 813 else if ((req->data[0] == ADB_PACKET) && (count > 1) 814 && (req->data[1] == ADB_BUSRESET)) { 815 ret = do_adb_reset_bus(); 816 up(&adb_probe_mutex); 817 atomic_dec(&state->n_pending); 818 if (ret == 0) 819 ret = count; 820 goto out; 821 } else { 822 req->reply_expected = ((req->data[1] & 0xc) == 0xc); 823 if (adb_controller && adb_controller->send_request) 824 ret = adb_controller->send_request(req, 0); 825 else 826 ret = -ENXIO; 827 up(&adb_probe_mutex); 828 } 829 830 if (ret != 0) { 831 atomic_dec(&state->n_pending); 832 goto out; 833 } 834 return count; 835 836 out: 837 kfree(req); 838 return ret; 839 } 840 841 static const struct file_operations adb_fops = { 842 .owner = THIS_MODULE, 843 .llseek = no_llseek, 844 .read = adb_read, 845 .write = adb_write, 846 .open = adb_open, 847 .release = adb_release, 848 }; 849 850 #ifdef CONFIG_PM 851 static const struct dev_pm_ops adb_dev_pm_ops = { 852 .suspend = adb_suspend, 853 .resume = adb_resume, 854 /* Hibernate hooks */ 855 .freeze = adb_freeze, 856 .thaw = adb_resume, 857 .poweroff = adb_poweroff, 858 .restore = adb_resume, 859 }; 860 #endif 861 862 static struct platform_driver adb_pfdrv = { 863 .driver = { 864 .name = "adb", 865 #ifdef CONFIG_PM 866 .pm = &adb_dev_pm_ops, 867 #endif 868 }, 869 }; 870 871 static struct platform_device adb_pfdev = { 872 .name = "adb", 873 }; 874 875 static int __init 876 adb_dummy_probe(struct platform_device *dev) 877 { 878 if (dev == &adb_pfdev) 879 return 0; 880 return -ENODEV; 881 } 882 883 static void __init 884 adbdev_init(void) 885 { 886 if (register_chrdev(ADB_MAJOR, "adb", &adb_fops)) { 887 pr_err("adb: unable to get major %d\n", ADB_MAJOR); 888 return; 889 } 890 891 adb_dev_class = class_create(THIS_MODULE, "adb"); 892 if (IS_ERR(adb_dev_class)) 893 return; 894 device_create(adb_dev_class, NULL, MKDEV(ADB_MAJOR, 0), NULL, "adb"); 895 896 platform_device_register(&adb_pfdev); 897 platform_driver_probe(&adb_pfdrv, adb_dummy_probe); 898 } 899