drivers/input/serio/serio.c

   1 /*
   2  *  The Serio abstraction module
   3  *
   4  *  Copyright (c) 1999-2004 Vojtech Pavlik
   5  *  Copyright (c) 2004 Dmitry Torokhov
   6  *  Copyright (c) 2003 Daniele Bellucci
   7  */
   8
   9 /*
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  23  *
  24  * Should you need to contact me, the author, you can do so either by
  25  * e-mail - mail your message to <vojtech@ucw.cz>, or by paper mail:
  26  * Vojtech Pavlik, Simunkova 1594, Prague 8, 182 00 Czech Republic
  27  */
  28
  29 #include <linux/stddef.h>
  30 #include <linux/module.h>
  31 #include <linux/serio.h>
  32 #include <linux/errno.h>
  33 #include <linux/wait.h>
  34 #include <linux/sched.h>
  35 #include <linux/slab.h>
  36 #include <linux/kthread.h>
  37 #include <linux/mutex.h>
  38 #include <linux/freezer.h>
  39
  40 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
  41 MODULE_DESCRIPTION("Serio abstraction core");
  42 MODULE_LICENSE("GPL");
  43
  44 EXPORT_SYMBOL(serio_interrupt);
  45 EXPORT_SYMBOL(__serio_register_port);
  46 EXPORT_SYMBOL(serio_unregister_port);
  47 EXPORT_SYMBOL(serio_unregister_child_port);
  48 EXPORT_SYMBOL(__serio_register_driver);
  49 EXPORT_SYMBOL(serio_unregister_driver);
  50 EXPORT_SYMBOL(serio_open);
  51 EXPORT_SYMBOL(serio_close);
  52 EXPORT_SYMBOL(serio_rescan);
  53 EXPORT_SYMBOL(serio_reconnect);
  54
  55 /*
  56  * serio_mutex protects entire serio subsystem and is taken every time
  57  * serio port or driver registrered or unregistered.
  58  */
  59 static DEFINE_MUTEX(serio_mutex);
  60
  61 static LIST_HEAD(serio_list);
  62
  63 static struct bus_type serio_bus;
  64
  65 static void serio_add_port(struct serio *serio);
  66 static void serio_reconnect_port(struct serio *serio);
  67 static void serio_disconnect_port(struct serio *serio);
  68 static void serio_attach_driver(struct serio_driver *drv);
  69
  70 static int serio_connect_driver(struct serio *serio, struct serio_driver *drv)
  71 {
  72         int retval;
  73
  74         mutex_lock(&serio->drv_mutex);
  75         retval = drv->connect(serio, drv);
  76         mutex_unlock(&serio->drv_mutex);
  77
  78         return retval;
  79 }
  80
  81 static int serio_reconnect_driver(struct serio *serio)
  82 {
  83         int retval = -1;
  84
  85         mutex_lock(&serio->drv_mutex);
  86         if (serio->drv && serio->drv->reconnect)
  87                 retval = serio->drv->reconnect(serio);
  88         mutex_unlock(&serio->drv_mutex);
  89
  90         return retval;
  91 }
  92
  93 static void serio_disconnect_driver(struct serio *serio)
  94 {
  95         mutex_lock(&serio->drv_mutex);
  96         if (serio->drv)
  97                 serio->drv->disconnect(serio);
  98         mutex_unlock(&serio->drv_mutex);
  99 }
 100
 101 static int serio_match_port(const struct serio_device_id *ids, struct serio *serio)
 102 {
 103         while (ids->type || ids->proto) {
 104                 if ((ids->type == SERIO_ANY || ids->type == serio->id.type) &&
 105                     (ids->proto == SERIO_ANY || ids->proto == serio->id.proto) &&
 106                     (ids->extra == SERIO_ANY || ids->extra == serio->id.extra) &&
 107                     (ids->id == SERIO_ANY || ids->id == serio->id.id))
 108                         return 1;
 109                 ids++;
 110         }
 111         return 0;
 112 }
 113
 114 /*
 115  * Basic serio -> driver core mappings
 116  */
 117
 118 static int serio_bind_driver(struct serio *serio, struct serio_driver *drv)
 119 {
 120         int error;
 121
 122         if (serio_match_port(drv->id_table, serio)) {
 123
 124                 serio->dev.driver = &drv->driver;
 125                 if (serio_connect_driver(serio, drv)) {
 126                         serio->dev.driver = NULL;
 127                         return -ENODEV;
 128                 }
 129
 130                 error = device_bind_driver(&serio->dev);
 131                 if (error) {
 132                         printk(KERN_WARNING
 133                                 "serio: device_bind_driver() failed "
 134                                 "for %s (%s) and %s, error: %d\n",
 135                                 serio->phys, serio->name,
 136                                 drv->description, error);
 137                         serio_disconnect_driver(serio);
 138                         serio->dev.driver = NULL;
 139                         return error;
 140                 }
 141         }
 142         return 0;
 143 }
 144
 145 static void serio_find_driver(struct serio *serio)
 146 {
 147         int error;
 148
 149         error = device_attach(&serio->dev);
 150         if (error < 0)
 151                 printk(KERN_WARNING
 152                         "serio: device_attach() failed for %s (%s), error: %d\n",
 153                         serio->phys, serio->name, error);
 154 }
 155
 156
 157 /*
 158  * Serio event processing.
 159  */
 160
 161 enum serio_event_type {
 162         SERIO_RESCAN_PORT,
 163         SERIO_RECONNECT_PORT,
 164         SERIO_REGISTER_PORT,
 165         SERIO_ATTACH_DRIVER,
 166 };
 167
 168 struct serio_event {
 169         enum serio_event_type type;
 170         void *object;
 171         struct module *owner;
 172         struct list_head node;
 173 };
 174
 175 static DEFINE_SPINLOCK(serio_event_lock);       /* protects serio_event_list */
 176 static LIST_HEAD(serio_event_list);
 177 static DECLARE_WAIT_QUEUE_HEAD(serio_wait);
 178 static struct task_struct *serio_task;
 179
 180 static int serio_queue_event(void *object, struct module *owner,
 181                              enum serio_event_type event_type)
 182 {
 183         unsigned long flags;
 184         struct serio_event *event;
 185         int retval = 0;
 186
 187         spin_lock_irqsave(&serio_event_lock, flags);
 188
 189         /*
 190          * Scan event list for the other events for the same serio port,
 191          * starting with the most recent one. If event is the same we
 192          * do not need add new one. If event is of different type we
 193          * need to add this event and should not look further because
 194          * we need to preseve sequence of distinct events.
 195          */
 196         list_for_each_entry_reverse(event, &serio_event_list, node) {
 197                 if (event->object == object) {
 198                         if (event->type == event_type)
 199                                 goto out;
 200                         break;
 201                 }
 202         }
 203
 204         event = kmalloc(sizeof(struct serio_event), GFP_ATOMIC);
 205         if (!event) {
 206                 printk(KERN_ERR
 207                         "serio: Not enough memory to queue event %d\n",
 208                         event_type);
 209                 retval = -ENOMEM;
 210                 goto out;
 211         }
 212
 213         if (!try_module_get(owner)) {
 214                 printk(KERN_WARNING
 215                         "serio: Can't get module reference, dropping event %d\n",
 216                         event_type);
 217                 kfree(event);
 218                 retval = -EINVAL;
 219                 goto out;
 220         }
 221
 222         event->type = event_type;
 223         event->object = object;
 224         event->owner = owner;
 225
 226         list_add_tail(&event->node, &serio_event_list);
 227         wake_up(&serio_wait);
 228
 229 out:
 230         spin_unlock_irqrestore(&serio_event_lock, flags);
 231         return retval;
 232 }
 233
 234 static void serio_free_event(struct serio_event *event)
 235 {
 236         module_put(event->owner);
 237         kfree(event);
 238 }
 239
 240 static void serio_remove_duplicate_events(struct serio_event *event)
 241 {
 242         struct list_head *node, *next;
 243         struct serio_event *e;
 244         unsigned long flags;
 245
 246         spin_lock_irqsave(&serio_event_lock, flags);
 247
 248         list_for_each_safe(node, next, &serio_event_list) {
 249                 e = list_entry(node, struct serio_event, node);
 250                 if (event->object == e->object) {
 251                         /*
 252                          * If this event is of different type we should not
 253                          * look further - we only suppress duplicate events
 254                          * that were sent back-to-back.
 255                          */
 256                         if (event->type != e->type)
 257                                 break;
 258
 259                         list_del_init(node);
 260                         serio_free_event(e);
 261                 }
 262         }
 263
 264         spin_unlock_irqrestore(&serio_event_lock, flags);
 265 }
 266
 267
 268 static struct serio_event *serio_get_event(void)
 269 {
 270         struct serio_event *event;
 271         struct list_head *node;
 272         unsigned long flags;
 273
 274         spin_lock_irqsave(&serio_event_lock, flags);
 275
 276         if (list_empty(&serio_event_list)) {
 277                 spin_unlock_irqrestore(&serio_event_lock, flags);
 278                 return NULL;
 279         }
 280
 281         node = serio_event_list.next;
 282         event = list_entry(node, struct serio_event, node);
 283         list_del_init(node);
 284
 285         spin_unlock_irqrestore(&serio_event_lock, flags);
 286
 287         return event;
 288 }
 289
 290 static void serio_handle_event(void)
 291 {
 292         struct serio_event *event;
 293
 294         mutex_lock(&serio_mutex);
 295
 296         /*
 297          * Note that we handle only one event here to give swsusp
 298          * a chance to freeze kseriod thread. Serio events should
 299          * be pretty rare so we are not concerned about taking
 300          * performance hit.
 301          */
 302         if ((event = serio_get_event())) {
 303
 304                 switch (event->type) {
 305                         case SERIO_REGISTER_PORT:
 306                                 serio_add_port(event->object);
 307                                 break;
 308
 309                         case SERIO_RECONNECT_PORT:
 310                                 serio_reconnect_port(event->object);
 311                                 break;
 312
 313                         case SERIO_RESCAN_PORT:
 314                                 serio_disconnect_port(event->object);
 315                                 serio_find_driver(event->object);
 316                                 break;
 317
 318                         case SERIO_ATTACH_DRIVER:
 319                                 serio_attach_driver(event->object);
 320                                 break;
 321
 322                         default:
 323                                 break;
 324                 }
 325
 326                 serio_remove_duplicate_events(event);
 327                 serio_free_event(event);
 328         }
 329
 330         mutex_unlock(&serio_mutex);
 331 }
 332
 333 /*
 334  * Remove all events that have been submitted for a given serio port.
 335  */
 336 static void serio_remove_pending_events(struct serio *serio)
 337 {
 338         struct list_head *node, *next;
 339         struct serio_event *event;
 340         unsigned long flags;
 341
 342         spin_lock_irqsave(&serio_event_lock, flags);
 343
 344         list_for_each_safe(node, next, &serio_event_list) {
 345                 event = list_entry(node, struct serio_event, node);
 346                 if (event->object == serio) {
 347                         list_del_init(node);
 348                         serio_free_event(event);
 349                 }
 350         }
 351
 352         spin_unlock_irqrestore(&serio_event_lock, flags);
 353 }
 354
 355 /*
 356  * Destroy child serio port (if any) that has not been fully registered yet.
 357  *
 358  * Note that we rely on the fact that port can have only one child and therefore
 359  * only one child registration request can be pending. Additionally, children
 360  * are registered by driver's connect() handler so there can't be a grandchild
 361  * pending registration together with a child.
 362  */
 363 static struct serio *serio_get_pending_child(struct serio *parent)
 364 {
 365         struct serio_event *event;
 366         struct serio *serio, *child = NULL;
 367         unsigned long flags;
 368
 369         spin_lock_irqsave(&serio_event_lock, flags);
 370
 371         list_for_each_entry(event, &serio_event_list, node) {
 372                 if (event->type == SERIO_REGISTER_PORT) {
 373                         serio = event->object;
 374                         if (serio->parent == parent) {
 375                                 child = serio;
 376                                 break;
 377                         }
 378                 }
 379         }
 380
 381         spin_unlock_irqrestore(&serio_event_lock, flags);
 382         return child;
 383 }
 384
 385 static int serio_thread(void *nothing)
 386 {
 387         set_freezable();
 388         do {
 389                 serio_handle_event();
 390                 wait_event_interruptible(serio_wait,
 391                         kthread_should_stop() || !list_empty(&serio_event_list));
 392                 try_to_freeze();
 393         } while (!kthread_should_stop());
 394
 395         printk(KERN_DEBUG "serio: kseriod exiting\n");
 396         return 0;
 397 }
 398
 399
 400 /*
 401  * Serio port operations
 402  */
 403
 404 static ssize_t serio_show_description(struct device *dev, struct device_attribute *attr, char *buf)
 405 {
 406         struct serio *serio = to_serio_port(dev);
 407         return sprintf(buf, "%s\n", serio->name);
 408 }
 409
 410 static ssize_t serio_show_modalias(struct device *dev, struct device_attribute *attr, char *buf)
 411 {
 412         struct serio *serio = to_serio_port(dev);
 413
 414         return sprintf(buf, "serio:ty%02Xpr%02Xid%02Xex%02X\n",
 415                         serio->id.type, serio->id.proto, serio->id.id, serio->id.extra);
 416 }
 417
 418 static ssize_t serio_show_id_type(struct device *dev, struct device_attribute *attr, char *buf)
 419 {
 420         struct serio *serio = to_serio_port(dev);
 421         return sprintf(buf, "%02x\n", serio->id.type);
 422 }
 423
 424 static ssize_t serio_show_id_proto(struct device *dev, struct device_attribute *attr, char *buf)
 425 {
 426         struct serio *serio = to_serio_port(dev);
 427         return sprintf(buf, "%02x\n", serio->id.proto);
 428 }
 429
 430 static ssize_t serio_show_id_id(struct device *dev, struct device_attribute *attr, char *buf)
 431 {
 432         struct serio *serio = to_serio_port(dev);
 433         return sprintf(buf, "%02x\n", serio->id.id);
 434 }
 435
 436 static ssize_t serio_show_id_extra(struct device *dev, struct device_attribute *attr, char *buf)
 437 {
 438         struct serio *serio = to_serio_port(dev);
 439         return sprintf(buf, "%02x\n", serio->id.extra);
 440 }
 441
 442 static DEVICE_ATTR(type, S_IRUGO, serio_show_id_type, NULL);
 443 static DEVICE_ATTR(proto, S_IRUGO, serio_show_id_proto, NULL);
 444 static DEVICE_ATTR(id, S_IRUGO, serio_show_id_id, NULL);
 445 static DEVICE_ATTR(extra, S_IRUGO, serio_show_id_extra, NULL);
 446
 447 static struct attribute *serio_device_id_attrs[] = {
 448         &dev_attr_type.attr,
 449         &dev_attr_proto.attr,
 450         &dev_attr_id.attr,
 451         &dev_attr_extra.attr,
 452         NULL
 453 };
 454
 455 static struct attribute_group serio_id_attr_group = {
 456         .name   = "id",
 457         .attrs  = serio_device_id_attrs,
 458 };
 459
 460 static ssize_t serio_rebind_driver(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
 461 {
 462         struct serio *serio = to_serio_port(dev);
 463         struct device_driver *drv;
 464         int error;
 465
 466         error = mutex_lock_interruptible(&serio_mutex);
 467         if (error)
 468                 return error;
 469
 470         if (!strncmp(buf, "none", count)) {
 471                 serio_disconnect_port(serio);
 472         } else if (!strncmp(buf, "reconnect", count)) {
 473                 serio_reconnect_port(serio);
 474         } else if (!strncmp(buf, "rescan", count)) {
 475                 serio_disconnect_port(serio);
 476                 serio_find_driver(serio);
 477         } else if ((drv = driver_find(buf, &serio_bus)) != NULL) {
 478                 serio_disconnect_port(serio);
 479                 error = serio_bind_driver(serio, to_serio_driver(drv));
 480                 put_driver(drv);
 481         } else {
 482                 error = -EINVAL;
 483         }
 484
 485         mutex_unlock(&serio_mutex);
 486
 487         return error ? error : count;
 488 }
 489
 490 static ssize_t serio_show_bind_mode(struct device *dev, struct device_attribute *attr, char *buf)
 491 {
 492         struct serio *serio = to_serio_port(dev);
 493         return sprintf(buf, "%s\n", serio->manual_bind ? "manual" : "auto");
 494 }
 495
 496 static ssize_t serio_set_bind_mode(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
 497 {
 498         struct serio *serio = to_serio_port(dev);
 499         int retval;
 500
 501         retval = count;
 502         if (!strncmp(buf, "manual", count)) {
 503                 serio->manual_bind = 1;
 504         } else if (!strncmp(buf, "auto", count)) {
 505                 serio->manual_bind = 0;
 506         } else {
 507                 retval = -EINVAL;
 508         }
 509
 510         return retval;
 511 }
 512
 513 static struct device_attribute serio_device_attrs[] = {
 514         __ATTR(description, S_IRUGO, serio_show_description, NULL),
 515         __ATTR(modalias, S_IRUGO, serio_show_modalias, NULL),
 516         __ATTR(drvctl, S_IWUSR, NULL, serio_rebind_driver),
 517         __ATTR(bind_mode, S_IWUSR | S_IRUGO, serio_show_bind_mode, serio_set_bind_mode),
 518         __ATTR_NULL
 519 };
 520
 521
 522 static void serio_release_port(struct device *dev)
 523 {
 524         struct serio *serio = to_serio_port(dev);
 525
 526         kfree(serio);
 527         module_put(THIS_MODULE);
 528 }
 529
 530 /*
 531  * Prepare serio port for registration.
 532  */
 533 static void serio_init_port(struct serio *serio)
 534 {
 535         static atomic_t serio_no = ATOMIC_INIT(0);
 536
 537         __module_get(THIS_MODULE);
 538
 539         INIT_LIST_HEAD(&serio->node);
 540         spin_lock_init(&serio->lock);
 541         mutex_init(&serio->drv_mutex);
 542         device_initialize(&serio->dev);
 543         snprintf(serio->dev.bus_id, sizeof(serio->dev.bus_id),
 544                  "serio%ld", (long)atomic_inc_return(&serio_no) - 1);
 545         serio->dev.bus = &serio_bus;
 546         serio->dev.release = serio_release_port;
 547         if (serio->parent) {
 548                 serio->dev.parent = &serio->parent->dev;
 549                 serio->depth = serio->parent->depth + 1;
 550         } else
 551                 serio->depth = 0;
 552         lockdep_set_subclass(&serio->lock, serio->depth);
 553 }
 554
 555 /*
 556  * Complete serio port registration.
 557  * Driver core will attempt to find appropriate driver for the port.
 558  */
 559 static void serio_add_port(struct serio *serio)
 560 {
 561         int error;
 562
 563         if (serio->parent) {
 564                 serio_pause_rx(serio->parent);
 565                 serio->parent->child = serio;
 566                 serio_continue_rx(serio->parent);
 567         }
 568
 569         list_add_tail(&serio->node, &serio_list);
 570         if (serio->start)
 571                 serio->start(serio);
 572         error = device_add(&serio->dev);
 573         if (error)
 574                 printk(KERN_ERR
 575                         "serio: device_add() failed for %s (%s), error: %d\n",
 576                         serio->phys, serio->name, error);
 577         else {
 578                 serio->registered = 1;
 579                 error = sysfs_create_group(&serio->dev.kobj, &serio_id_attr_group);
 580                 if (error)
 581                         printk(KERN_ERR
 582                                 "serio: sysfs_create_group() failed for %s (%s), error: %d\n",
 583                                 serio->phys, serio->name, error);
 584         }
 585 }
 586
 587 /*
 588  * serio_destroy_port() completes deregistration process and removes
 589  * port from the system
 590  */
 591 static void serio_destroy_port(struct serio *serio)
 592 {
 593         struct serio *child;
 594
 595         child = serio_get_pending_child(serio);
 596         if (child) {
 597                 serio_remove_pending_events(child);
 598                 put_device(&child->dev);
 599         }
 600
 601         if (serio->stop)
 602                 serio->stop(serio);
 603
 604         if (serio->parent) {
 605                 serio_pause_rx(serio->parent);
 606                 serio->parent->child = NULL;
 607                 serio_continue_rx(serio->parent);
 608                 serio->parent = NULL;
 609         }
 610
 611         if (serio->registered) {
 612                 sysfs_remove_group(&serio->dev.kobj, &serio_id_attr_group);
 613                 device_del(&serio->dev);
 614                 serio->registered = 0;
 615         }
 616
 617         list_del_init(&serio->node);
 618         serio_remove_pending_events(serio);
 619         put_device(&serio->dev);
 620 }
 621
 622 /*
 623  * Reconnect serio port and all its children (re-initialize attached devices)
 624  */
 625 static void serio_reconnect_port(struct serio *serio)
 626 {
 627         do {
 628                 if (serio_reconnect_driver(serio)) {
 629                         serio_disconnect_port(serio);
 630                         serio_find_driver(serio);
 631                         /* Ok, old children are now gone, we are done */
 632                         break;
 633                 }
 634                 serio = serio->child;
 635         } while (serio);
 636 }
 637
 638 /*
 639  * serio_disconnect_port() unbinds a port from its driver. As a side effect
 640  * all child ports are unbound and destroyed.
 641  */
 642 static void serio_disconnect_port(struct serio *serio)
 643 {
 644         struct serio *s, *parent;
 645
 646         if (serio->child) {
 647                 /*
 648                  * Children ports should be disconnected and destroyed
 649                  * first, staring with the leaf one, since we don't want
 650                  * to do recursion
 651                  */
 652                 for (s = serio; s->child; s = s->child)
 653                         /* empty */;
 654
 655                 do {
 656                         parent = s->parent;
 657
 658                         device_release_driver(&s->dev);
 659                         serio_destroy_port(s);
 660                 } while ((s = parent) != serio);
 661         }
 662
 663         /*
 664          * Ok, no children left, now disconnect this port
 665          */
 666         device_release_driver(&serio->dev);
 667 }
 668
 669 void serio_rescan(struct serio *serio)
 670 {
 671         serio_queue_event(serio, NULL, SERIO_RESCAN_PORT);
 672 }
 673
 674 void serio_reconnect(struct serio *serio)
 675 {
 676         serio_queue_event(serio, NULL, SERIO_RECONNECT_PORT);
 677 }
 678
 679 /*
 680  * Submits register request to kseriod for subsequent execution.
 681  * Note that port registration is always asynchronous.
 682  */
 683 void __serio_register_port(struct serio *serio, struct module *owner)
 684 {
 685         serio_init_port(serio);
 686         serio_queue_event(serio, owner, SERIO_REGISTER_PORT);
 687 }
 688
 689 /*
 690  * Synchronously unregisters serio port.
 691  */
 692 void serio_unregister_port(struct serio *serio)
 693 {
 694         mutex_lock(&serio_mutex);
 695         serio_disconnect_port(serio);
 696         serio_destroy_port(serio);
 697         mutex_unlock(&serio_mutex);
 698 }
 699
 700 /*
 701  * Safely unregisters child port if one is present.
 702  */
 703 void serio_unregister_child_port(struct serio *serio)
 704 {
 705         mutex_lock(&serio_mutex);
 706         if (serio->child) {
 707                 serio_disconnect_port(serio->child);
 708                 serio_destroy_port(serio->child);
 709         }
 710         mutex_unlock(&serio_mutex);
 711 }
 712
 713
 714 /*
 715  * Serio driver operations
 716  */
 717
 718 static ssize_t serio_driver_show_description(struct device_driver *drv, char *buf)
 719 {
 720         struct serio_driver *driver = to_serio_driver(drv);
 721         return sprintf(buf, "%s\n", driver->description ? driver->description : "(none)");
 722 }
 723
 724 static ssize_t serio_driver_show_bind_mode(struct device_driver *drv, char *buf)
 725 {
 726         struct serio_driver *serio_drv = to_serio_driver(drv);
 727         return sprintf(buf, "%s\n", serio_drv->manual_bind ? "manual" : "auto");
 728 }
 729
 730 static ssize_t serio_driver_set_bind_mode(struct device_driver *drv, const char *buf, size_t count)
 731 {
 732         struct serio_driver *serio_drv = to_serio_driver(drv);
 733         int retval;
 734
 735         retval = count;
 736         if (!strncmp(buf, "manual", count)) {
 737                 serio_drv->manual_bind = 1;
 738         } else if (!strncmp(buf, "auto", count)) {
 739                 serio_drv->manual_bind = 0;
 740         } else {
 741                 retval = -EINVAL;
 742         }
 743
 744         return retval;
 745 }
 746
 747
 748 static struct driver_attribute serio_driver_attrs[] = {
 749         __ATTR(description, S_IRUGO, serio_driver_show_description, NULL),
 750         __ATTR(bind_mode, S_IWUSR | S_IRUGO,
 751                 serio_driver_show_bind_mode, serio_driver_set_bind_mode),
 752         __ATTR_NULL
 753 };
 754
 755 static int serio_driver_probe(struct device *dev)
 756 {
 757         struct serio *serio = to_serio_port(dev);
 758         struct serio_driver *drv = to_serio_driver(dev->driver);
 759
 760         return serio_connect_driver(serio, drv);
 761 }
 762
 763 static int serio_driver_remove(struct device *dev)
 764 {
 765         struct serio *serio = to_serio_port(dev);
 766
 767         serio_disconnect_driver(serio);
 768         return 0;
 769 }
 770
 771 static void serio_cleanup(struct serio *serio)
 772 {
 773         mutex_lock(&serio->drv_mutex);
 774         if (serio->drv && serio->drv->cleanup)
 775                 serio->drv->cleanup(serio);
 776         mutex_unlock(&serio->drv_mutex);
 777 }
 778
 779 static void serio_shutdown(struct device *dev)
 780 {
 781         struct serio *serio = to_serio_port(dev);
 782
 783         serio_cleanup(serio);
 784 }
 785
 786 static void serio_attach_driver(struct serio_driver *drv)
 787 {
 788         int error;
 789
 790         error = driver_attach(&drv->driver);
 791         if (error)
 792                 printk(KERN_WARNING
 793                         "serio: driver_attach() failed for %s with error %d\n",
 794                         drv->driver.name, error);
 795 }
 796
 797 int __serio_register_driver(struct serio_driver *drv, struct module *owner, const char *mod_name)
 798 {
 799         int manual_bind = drv->manual_bind;
 800         int error;
 801
 802         drv->driver.bus = &serio_bus;
 803         drv->driver.owner = owner;
 804         drv->driver.mod_name = mod_name;
 805
 806         /*
 807          * Temporarily disable automatic binding because probing
 808          * takes long time and we are better off doing it in kseriod
 809          */
 810         drv->manual_bind = 1;
 811
 812         error = driver_register(&drv->driver);
 813         if (error) {
 814                 printk(KERN_ERR
 815                         "serio: driver_register() failed for %s, error: %d\n",
 816                         drv->driver.name, error);
 817                 return error;
 818         }
 819
 820         /*
 821          * Restore original bind mode and let kseriod bind the
 822          * driver to free ports
 823          */
 824         if (!manual_bind) {
 825                 drv->manual_bind = 0;
 826                 error = serio_queue_event(drv, NULL, SERIO_ATTACH_DRIVER);
 827                 if (error) {
 828                         driver_unregister(&drv->driver);
 829                         return error;
 830                 }
 831         }
 832
 833         return 0;
 834 }
 835
 836 void serio_unregister_driver(struct serio_driver *drv)
 837 {
 838         struct serio *serio;
 839
 840         mutex_lock(&serio_mutex);
 841         drv->manual_bind = 1;   /* so serio_find_driver ignores it */
 842
 843 start_over:
 844         list_for_each_entry(serio, &serio_list, node) {
 845                 if (serio->drv == drv) {
 846                         serio_disconnect_port(serio);
 847                         serio_find_driver(serio);
 848                         /* we could've deleted some ports, restart */
 849                         goto start_over;
 850                 }
 851         }
 852
 853         driver_unregister(&drv->driver);
 854         mutex_unlock(&serio_mutex);
 855 }
 856
 857 static void serio_set_drv(struct serio *serio, struct serio_driver *drv)
 858 {
 859         serio_pause_rx(serio);
 860         serio->drv = drv;
 861         serio_continue_rx(serio);
 862 }
 863
 864 static int serio_bus_match(struct device *dev, struct device_driver *drv)
 865 {
 866         struct serio *serio = to_serio_port(dev);
 867         struct serio_driver *serio_drv = to_serio_driver(drv);
 868
 869         if (serio->manual_bind || serio_drv->manual_bind)
 870                 return 0;
 871
 872         return serio_match_port(serio_drv->id_table, serio);
 873 }
 874
 875 #ifdef CONFIG_HOTPLUG
 876
 877 #define SERIO_ADD_UEVENT_VAR(fmt, val...)                               \
 878         do {                                                            \
 879                 int err = add_uevent_var(env, fmt, val);                \
 880                 if (err)                                                \
 881                         return err;                                     \
 882         } while (0)
 883
 884 static int serio_uevent(struct device *dev, struct kobj_uevent_env *env)
 885 {
 886         struct serio *serio;
 887
 888         if (!dev)
 889                 return -ENODEV;
 890
 891         serio = to_serio_port(dev);
 892
 893         SERIO_ADD_UEVENT_VAR("SERIO_TYPE=%02x", serio->id.type);
 894         SERIO_ADD_UEVENT_VAR("SERIO_PROTO=%02x", serio->id.proto);
 895         SERIO_ADD_UEVENT_VAR("SERIO_ID=%02x", serio->id.id);
 896         SERIO_ADD_UEVENT_VAR("SERIO_EXTRA=%02x", serio->id.extra);
 897         SERIO_ADD_UEVENT_VAR("MODALIAS=serio:ty%02Xpr%02Xid%02Xex%02X",
 898                                 serio->id.type, serio->id.proto, serio->id.id, serio->id.extra);
 899
 900         return 0;
 901 }
 902 #undef SERIO_ADD_UEVENT_VAR
 903
 904 #else
 905
 906 static int serio_uevent(struct device *dev, struct kobj_uevent_env *env)
 907 {
 908         return -ENODEV;
 909 }
 910
 911 #endif /* CONFIG_HOTPLUG */
 912
 913 #ifdef CONFIG_PM
 914 static int serio_suspend(struct device *dev, pm_message_t state)
 915 {
 916         if (dev->power.power_state.event != state.event) {
 917                 if (state.event == PM_EVENT_SUSPEND)
 918                         serio_cleanup(to_serio_port(dev));
 919
 920                 dev->power.power_state = state;
 921         }
 922
 923         return 0;
 924 }
 925
 926 static int serio_resume(struct device *dev)
 927 {
 928         struct serio *serio = to_serio_port(dev);
 929
 930         if (dev->power.power_state.event != PM_EVENT_ON &&
 931             serio_reconnect_driver(serio)) {
 932                 /*
 933                  * Driver re-probing can take a while, so better let kseriod
 934                  * deal with it.
 935                  */
 936                 serio_rescan(serio);
 937         }
 938
 939         dev->power.power_state = PMSG_ON;
 940
 941         return 0;
 942 }
 943 #endif /* CONFIG_PM */
 944
 945 /* called from serio_driver->connect/disconnect methods under serio_mutex */
 946 int serio_open(struct serio *serio, struct serio_driver *drv)
 947 {
 948         serio_set_drv(serio, drv);
 949
 950         if (serio->open && serio->open(serio)) {
 951                 serio_set_drv(serio, NULL);
 952                 return -1;
 953         }
 954         return 0;
 955 }
 956
 957 /* called from serio_driver->connect/disconnect methods under serio_mutex */
 958 void serio_close(struct serio *serio)
 959 {
 960         if (serio->close)
 961                 serio->close(serio);
 962
 963         serio_set_drv(serio, NULL);
 964 }
 965
 966 irqreturn_t serio_interrupt(struct serio *serio,
 967                 unsigned char data, unsigned int dfl)
 968 {
 969         unsigned long flags;
 970         irqreturn_t ret = IRQ_NONE;
 971
 972         spin_lock_irqsave(&serio->lock, flags);
 973
 974         if (likely(serio->drv)) {
 975                 ret = serio->drv->interrupt(serio, data, dfl);
 976         } else if (!dfl && serio->registered) {
 977                 serio_rescan(serio);
 978                 ret = IRQ_HANDLED;
 979         }
 980
 981         spin_unlock_irqrestore(&serio->lock, flags);
 982
 983         return ret;
 984 }
 985
 986 static struct bus_type serio_bus = {
 987         .name           = "serio",
 988         .dev_attrs      = serio_device_attrs,
 989         .drv_attrs      = serio_driver_attrs,
 990         .match          = serio_bus_match,
 991         .uevent         = serio_uevent,
 992         .probe          = serio_driver_probe,
 993         .remove         = serio_driver_remove,
 994         .shutdown       = serio_shutdown,
 995 #ifdef CONFIG_PM
 996         .suspend        = serio_suspend,
 997         .resume         = serio_resume,
 998 #endif
 999 };
1000
1001 static int __init serio_init(void)
1002 {
1003         int error;
1004
1005         error = bus_register(&serio_bus);
1006         if (error) {
1007                 printk(KERN_ERR "serio: failed to register serio bus, error: %d\n", error);
1008                 return error;
1009         }
1010
1011         serio_task = kthread_run(serio_thread, NULL, "kseriod");
1012         if (IS_ERR(serio_task)) {
1013                 bus_unregister(&serio_bus);
1014                 error = PTR_ERR(serio_task);
1015                 printk(KERN_ERR "serio: Failed to start kseriod, error: %d\n", error);
1016                 return error;
1017         }
1018
1019         return 0;
1020 }
1021
1022 static void __exit serio_exit(void)
1023 {
1024         bus_unregister(&serio_bus);
1025         kthread_stop(serio_task);
1026 }
1027
1028 subsys_initcall(serio_init);
1029 module_exit(serio_exit);