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 /*
  45  * serio_mutex protects entire serio subsystem and is taken every time
  46  * serio port or driver registrered or unregistered.
  47  */
  48 static DEFINE_MUTEX(serio_mutex);
  49
  50 static LIST_HEAD(serio_list);
  51
  52 static struct bus_type serio_bus;
  53
  54 static void serio_add_port(struct serio *serio);
  55 static int serio_reconnect_port(struct serio *serio);
  56 static void serio_disconnect_port(struct serio *serio);
  57 static void serio_reconnect_chain(struct serio *serio);
  58 static void serio_attach_driver(struct serio_driver *drv);
  59
  60 static int serio_connect_driver(struct serio *serio, struct serio_driver *drv)
  61 {
  62         int retval;
  63
  64         mutex_lock(&serio->drv_mutex);
  65         retval = drv->connect(serio, drv);
  66         mutex_unlock(&serio->drv_mutex);
  67
  68         return retval;
  69 }
  70
  71 static int serio_reconnect_driver(struct serio *serio)
  72 {
  73         int retval = -1;
  74
  75         mutex_lock(&serio->drv_mutex);
  76         if (serio->drv && serio->drv->reconnect)
  77                 retval = serio->drv->reconnect(serio);
  78         mutex_unlock(&serio->drv_mutex);
  79
  80         return retval;
  81 }
  82
  83 static void serio_disconnect_driver(struct serio *serio)
  84 {
  85         mutex_lock(&serio->drv_mutex);
  86         if (serio->drv)
  87                 serio->drv->disconnect(serio);
  88         mutex_unlock(&serio->drv_mutex);
  89 }
  90
  91 static int serio_match_port(const struct serio_device_id *ids, struct serio *serio)
  92 {
  93         while (ids->type || ids->proto) {
  94                 if ((ids->type == SERIO_ANY || ids->type == serio->id.type) &&
  95                     (ids->proto == SERIO_ANY || ids->proto == serio->id.proto) &&
  96                     (ids->extra == SERIO_ANY || ids->extra == serio->id.extra) &&
  97                     (ids->id == SERIO_ANY || ids->id == serio->id.id))
  98                         return 1;
  99                 ids++;
 100         }
 101         return 0;
 102 }
 103
 104 /*
 105  * Basic serio -> driver core mappings
 106  */
 107
 108 static int serio_bind_driver(struct serio *serio, struct serio_driver *drv)
 109 {
 110         int error;
 111
 112         if (serio_match_port(drv->id_table, serio)) {
 113
 114                 serio->dev.driver = &drv->driver;
 115                 if (serio_connect_driver(serio, drv)) {
 116                         serio->dev.driver = NULL;
 117                         return -ENODEV;
 118                 }
 119
 120                 error = device_bind_driver(&serio->dev);
 121                 if (error) {
 122                         printk(KERN_WARNING
 123                                 "serio: device_bind_driver() failed "
 124                                 "for %s (%s) and %s, error: %d\n",
 125                                 serio->phys, serio->name,
 126                                 drv->description, error);
 127                         serio_disconnect_driver(serio);
 128                         serio->dev.driver = NULL;
 129                         return error;
 130                 }
 131         }
 132         return 0;
 133 }
 134
 135 static void serio_find_driver(struct serio *serio)
 136 {
 137         int error;
 138
 139         error = device_attach(&serio->dev);
 140         if (error < 0)
 141                 printk(KERN_WARNING
 142                         "serio: device_attach() failed for %s (%s), error: %d\n",
 143                         serio->phys, serio->name, error);
 144 }
 145
 146
 147 /*
 148  * Serio event processing.
 149  */
 150
 151 enum serio_event_type {
 152         SERIO_RESCAN_PORT,
 153         SERIO_RECONNECT_PORT,
 154         SERIO_RECONNECT_CHAIN,
 155         SERIO_REGISTER_PORT,
 156         SERIO_ATTACH_DRIVER,
 157 };
 158
 159 struct serio_event {
 160         enum serio_event_type type;
 161         void *object;
 162         struct module *owner;
 163         struct list_head node;
 164 };
 165
 166 static DEFINE_SPINLOCK(serio_event_lock);       /* protects serio_event_list */
 167 static LIST_HEAD(serio_event_list);
 168 static DECLARE_WAIT_QUEUE_HEAD(serio_wait);
 169 static struct task_struct *serio_task;
 170
 171 static int serio_queue_event(void *object, struct module *owner,
 172                              enum serio_event_type event_type)
 173 {
 174         unsigned long flags;
 175         struct serio_event *event;
 176         int retval = 0;
 177
 178         spin_lock_irqsave(&serio_event_lock, flags);
 179
 180         /*
 181          * Scan event list for the other events for the same serio port,
 182          * starting with the most recent one. If event is the same we
 183          * do not need add new one. If event is of different type we
 184          * need to add this event and should not look further because
 185          * we need to preseve sequence of distinct events.
 186          */
 187         list_for_each_entry_reverse(event, &serio_event_list, node) {
 188                 if (event->object == object) {
 189                         if (event->type == event_type)
 190                                 goto out;
 191                         break;
 192                 }
 193         }
 194
 195         event = kmalloc(sizeof(struct serio_event), GFP_ATOMIC);
 196         if (!event) {
 197                 printk(KERN_ERR
 198                         "serio: Not enough memory to queue event %d\n",
 199                         event_type);
 200                 retval = -ENOMEM;
 201                 goto out;
 202         }
 203
 204         if (!try_module_get(owner)) {
 205                 printk(KERN_WARNING
 206                         "serio: Can't get module reference, dropping event %d\n",
 207                         event_type);
 208                 kfree(event);
 209                 retval = -EINVAL;
 210                 goto out;
 211         }
 212
 213         event->type = event_type;
 214         event->object = object;
 215         event->owner = owner;
 216
 217         list_add_tail(&event->node, &serio_event_list);
 218         wake_up(&serio_wait);
 219
 220 out:
 221         spin_unlock_irqrestore(&serio_event_lock, flags);
 222         return retval;
 223 }
 224
 225 static void serio_free_event(struct serio_event *event)
 226 {
 227         module_put(event->owner);
 228         kfree(event);
 229 }
 230
 231 static void serio_remove_duplicate_events(struct serio_event *event)
 232 {
 233         struct list_head *node, *next;
 234         struct serio_event *e;
 235         unsigned long flags;
 236
 237         spin_lock_irqsave(&serio_event_lock, flags);
 238
 239         list_for_each_safe(node, next, &serio_event_list) {
 240                 e = list_entry(node, struct serio_event, node);
 241                 if (event->object == e->object) {
 242                         /*
 243                          * If this event is of different type we should not
 244                          * look further - we only suppress duplicate events
 245                          * that were sent back-to-back.
 246                          */
 247                         if (event->type != e->type)
 248                                 break;
 249
 250                         list_del_init(node);
 251                         serio_free_event(e);
 252                 }
 253         }
 254
 255         spin_unlock_irqrestore(&serio_event_lock, flags);
 256 }
 257
 258
 259 static struct serio_event *serio_get_event(void)
 260 {
 261         struct serio_event *event;
 262         struct list_head *node;
 263         unsigned long flags;
 264
 265         spin_lock_irqsave(&serio_event_lock, flags);
 266
 267         if (list_empty(&serio_event_list)) {
 268                 spin_unlock_irqrestore(&serio_event_lock, flags);
 269                 return NULL;
 270         }
 271
 272         node = serio_event_list.next;
 273         event = list_entry(node, struct serio_event, node);
 274         list_del_init(node);
 275
 276         spin_unlock_irqrestore(&serio_event_lock, flags);
 277
 278         return event;
 279 }
 280
 281 static void serio_handle_event(void)
 282 {
 283         struct serio_event *event;
 284
 285         mutex_lock(&serio_mutex);
 286
 287         /*
 288          * Note that we handle only one event here to give swsusp
 289          * a chance to freeze kseriod thread. Serio events should
 290          * be pretty rare so we are not concerned about taking
 291          * performance hit.
 292          */
 293         if ((event = serio_get_event())) {
 294
 295                 switch (event->type) {
 296                         case SERIO_REGISTER_PORT:
 297                                 serio_add_port(event->object);
 298                                 break;
 299
 300                         case SERIO_RECONNECT_PORT:
 301                                 serio_reconnect_port(event->object);
 302                                 break;
 303
 304                         case SERIO_RESCAN_PORT:
 305                                 serio_disconnect_port(event->object);
 306                                 serio_find_driver(event->object);
 307                                 break;
 308
 309                         case SERIO_RECONNECT_CHAIN:
 310                                 serio_reconnect_chain(event->object);
 311                                 break;
 312
 313                         case SERIO_ATTACH_DRIVER:
 314                                 serio_attach_driver(event->object);
 315                                 break;
 316
 317                         default:
 318                                 break;
 319                 }
 320
 321                 serio_remove_duplicate_events(event);
 322                 serio_free_event(event);
 323         }
 324
 325         mutex_unlock(&serio_mutex);
 326 }
 327
 328 /*
 329  * Remove all events that have been submitted for a given
 330  * object, be it serio port or driver.
 331  */
 332 static void serio_remove_pending_events(void *object)
 333 {
 334         struct list_head *node, *next;
 335         struct serio_event *event;
 336         unsigned long flags;
 337
 338         spin_lock_irqsave(&serio_event_lock, flags);
 339
 340         list_for_each_safe(node, next, &serio_event_list) {
 341                 event = list_entry(node, struct serio_event, node);
 342                 if (event->object == object) {
 343                         list_del_init(node);
 344                         serio_free_event(event);
 345                 }
 346         }
 347
 348         spin_unlock_irqrestore(&serio_event_lock, flags);
 349 }
 350
 351 /*
 352  * Destroy child serio port (if any) that has not been fully registered yet.
 353  *
 354  * Note that we rely on the fact that port can have only one child and therefore
 355  * only one child registration request can be pending. Additionally, children
 356  * are registered by driver's connect() handler so there can't be a grandchild
 357  * pending registration together with a child.
 358  */
 359 static struct serio *serio_get_pending_child(struct serio *parent)
 360 {
 361         struct serio_event *event;
 362         struct serio *serio, *child = NULL;
 363         unsigned long flags;
 364
 365         spin_lock_irqsave(&serio_event_lock, flags);
 366
 367         list_for_each_entry(event, &serio_event_list, node) {
 368                 if (event->type == SERIO_REGISTER_PORT) {
 369                         serio = event->object;
 370                         if (serio->parent == parent) {
 371                                 child = serio;
 372                                 break;
 373                         }
 374                 }
 375         }
 376
 377         spin_unlock_irqrestore(&serio_event_lock, flags);
 378         return child;
 379 }
 380
 381 static int serio_thread(void *nothing)
 382 {
 383         set_freezable();
 384         do {
 385                 serio_handle_event();
 386                 wait_event_freezable(serio_wait,
 387                         kthread_should_stop() || !list_empty(&serio_event_list));
 388         } while (!kthread_should_stop());
 389
 390         printk(KERN_DEBUG "serio: kseriod exiting\n");
 391         return 0;
 392 }
 393
 394
 395 /*
 396  * Serio port operations
 397  */
 398
 399 static ssize_t serio_show_description(struct device *dev, struct device_attribute *attr, char *buf)
 400 {
 401         struct serio *serio = to_serio_port(dev);
 402         return sprintf(buf, "%s\n", serio->name);
 403 }
 404
 405 static ssize_t serio_show_modalias(struct device *dev, struct device_attribute *attr, char *buf)
 406 {
 407         struct serio *serio = to_serio_port(dev);
 408
 409         return sprintf(buf, "serio:ty%02Xpr%02Xid%02Xex%02X\n",
 410                         serio->id.type, serio->id.proto, serio->id.id, serio->id.extra);
 411 }
 412
 413 static ssize_t serio_show_id_type(struct device *dev, struct device_attribute *attr, char *buf)
 414 {
 415         struct serio *serio = to_serio_port(dev);
 416         return sprintf(buf, "%02x\n", serio->id.type);
 417 }
 418
 419 static ssize_t serio_show_id_proto(struct device *dev, struct device_attribute *attr, char *buf)
 420 {
 421         struct serio *serio = to_serio_port(dev);
 422         return sprintf(buf, "%02x\n", serio->id.proto);
 423 }
 424
 425 static ssize_t serio_show_id_id(struct device *dev, struct device_attribute *attr, char *buf)
 426 {
 427         struct serio *serio = to_serio_port(dev);
 428         return sprintf(buf, "%02x\n", serio->id.id);
 429 }
 430
 431 static ssize_t serio_show_id_extra(struct device *dev, struct device_attribute *attr, char *buf)
 432 {
 433         struct serio *serio = to_serio_port(dev);
 434         return sprintf(buf, "%02x\n", serio->id.extra);
 435 }
 436
 437 static DEVICE_ATTR(type, S_IRUGO, serio_show_id_type, NULL);
 438 static DEVICE_ATTR(proto, S_IRUGO, serio_show_id_proto, NULL);
 439 static DEVICE_ATTR(id, S_IRUGO, serio_show_id_id, NULL);
 440 static DEVICE_ATTR(extra, S_IRUGO, serio_show_id_extra, NULL);
 441
 442 static struct attribute *serio_device_id_attrs[] = {
 443         &dev_attr_type.attr,
 444         &dev_attr_proto.attr,
 445         &dev_attr_id.attr,
 446         &dev_attr_extra.attr,
 447         NULL
 448 };
 449
 450 static struct attribute_group serio_id_attr_group = {
 451         .name   = "id",
 452         .attrs  = serio_device_id_attrs,
 453 };
 454
 455 static ssize_t serio_rebind_driver(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
 456 {
 457         struct serio *serio = to_serio_port(dev);
 458         struct device_driver *drv;
 459         int error;
 460
 461         error = mutex_lock_interruptible(&serio_mutex);
 462         if (error)
 463                 return error;
 464
 465         if (!strncmp(buf, "none", count)) {
 466                 serio_disconnect_port(serio);
 467         } else if (!strncmp(buf, "reconnect", count)) {
 468                 serio_reconnect_chain(serio);
 469         } else if (!strncmp(buf, "rescan", count)) {
 470                 serio_disconnect_port(serio);
 471                 serio_find_driver(serio);
 472         } else if ((drv = driver_find(buf, &serio_bus)) != NULL) {
 473                 serio_disconnect_port(serio);
 474                 error = serio_bind_driver(serio, to_serio_driver(drv));
 475                 put_driver(drv);
 476         } else {
 477                 error = -EINVAL;
 478         }
 479
 480         mutex_unlock(&serio_mutex);
 481
 482         return error ? error : count;
 483 }
 484
 485 static ssize_t serio_show_bind_mode(struct device *dev, struct device_attribute *attr, char *buf)
 486 {
 487         struct serio *serio = to_serio_port(dev);
 488         return sprintf(buf, "%s\n", serio->manual_bind ? "manual" : "auto");
 489 }
 490
 491 static ssize_t serio_set_bind_mode(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
 492 {
 493         struct serio *serio = to_serio_port(dev);
 494         int retval;
 495
 496         retval = count;
 497         if (!strncmp(buf, "manual", count)) {
 498                 serio->manual_bind = true;
 499         } else if (!strncmp(buf, "auto", count)) {
 500                 serio->manual_bind = false;
 501         } else {
 502                 retval = -EINVAL;
 503         }
 504
 505         return retval;
 506 }
 507
 508 static struct device_attribute serio_device_attrs[] = {
 509         __ATTR(description, S_IRUGO, serio_show_description, NULL),
 510         __ATTR(modalias, S_IRUGO, serio_show_modalias, NULL),
 511         __ATTR(drvctl, S_IWUSR, NULL, serio_rebind_driver),
 512         __ATTR(bind_mode, S_IWUSR | S_IRUGO, serio_show_bind_mode, serio_set_bind_mode),
 513         __ATTR_NULL
 514 };
 515
 516
 517 static void serio_release_port(struct device *dev)
 518 {
 519         struct serio *serio = to_serio_port(dev);
 520
 521         kfree(serio);
 522         module_put(THIS_MODULE);
 523 }
 524
 525 /*
 526  * Prepare serio port for registration.
 527  */
 528 static void serio_init_port(struct serio *serio)
 529 {
 530         static atomic_t serio_no = ATOMIC_INIT(0);
 531
 532         __module_get(THIS_MODULE);
 533
 534         INIT_LIST_HEAD(&serio->node);
 535         spin_lock_init(&serio->lock);
 536         mutex_init(&serio->drv_mutex);
 537         device_initialize(&serio->dev);
 538         dev_set_name(&serio->dev, "serio%ld",
 539                         (long)atomic_inc_return(&serio_no) - 1);
 540         serio->dev.bus = &serio_bus;
 541         serio->dev.release = serio_release_port;
 542         if (serio->parent) {
 543                 serio->dev.parent = &serio->parent->dev;
 544                 serio->depth = serio->parent->depth + 1;
 545         } else
 546                 serio->depth = 0;
 547         lockdep_set_subclass(&serio->lock, serio->depth);
 548 }
 549
 550 /*
 551  * Complete serio port registration.
 552  * Driver core will attempt to find appropriate driver for the port.
 553  */
 554 static void serio_add_port(struct serio *serio)
 555 {
 556         int error;
 557
 558         if (serio->parent) {
 559                 serio_pause_rx(serio->parent);
 560                 serio->parent->child = serio;
 561                 serio_continue_rx(serio->parent);
 562         }
 563
 564         list_add_tail(&serio->node, &serio_list);
 565         if (serio->start)
 566                 serio->start(serio);
 567         error = device_add(&serio->dev);
 568         if (error)
 569                 printk(KERN_ERR
 570                         "serio: device_add() failed for %s (%s), error: %d\n",
 571                         serio->phys, serio->name, error);
 572         else {
 573                 serio->registered = true;
 574                 error = sysfs_create_group(&serio->dev.kobj, &serio_id_attr_group);
 575                 if (error)
 576                         printk(KERN_ERR
 577                                 "serio: sysfs_create_group() failed for %s (%s), error: %d\n",
 578                                 serio->phys, serio->name, error);
 579         }
 580 }
 581
 582 /*
 583  * serio_destroy_port() completes deregistration process and removes
 584  * port from the system
 585  */
 586 static void serio_destroy_port(struct serio *serio)
 587 {
 588         struct serio *child;
 589
 590         child = serio_get_pending_child(serio);
 591         if (child) {
 592                 serio_remove_pending_events(child);
 593                 put_device(&child->dev);
 594         }
 595
 596         if (serio->stop)
 597                 serio->stop(serio);
 598
 599         if (serio->parent) {
 600                 serio_pause_rx(serio->parent);
 601                 serio->parent->child = NULL;
 602                 serio_continue_rx(serio->parent);
 603                 serio->parent = NULL;
 604         }
 605
 606         if (serio->registered) {
 607                 sysfs_remove_group(&serio->dev.kobj, &serio_id_attr_group);
 608                 device_del(&serio->dev);
 609                 serio->registered = false;
 610         }
 611
 612         list_del_init(&serio->node);
 613         serio_remove_pending_events(serio);
 614         put_device(&serio->dev);
 615 }
 616
 617 /*
 618  * Reconnect serio port (re-initialize attached device).
 619  * If reconnect fails (old device is no longer attached or
 620  * there was no device to begin with) we do full rescan in
 621  * hope of finding a driver for the port.
 622  */
 623 static int serio_reconnect_port(struct serio *serio)
 624 {
 625         int error = serio_reconnect_driver(serio);
 626
 627         if (error) {
 628                 serio_disconnect_port(serio);
 629                 serio_find_driver(serio);
 630         }
 631
 632         return error;
 633 }
 634
 635 /*
 636  * Reconnect serio port and all its children (re-initialize attached devices)
 637  */
 638 static void serio_reconnect_chain(struct serio *serio)
 639 {
 640         do {
 641                 if (serio_reconnect_port(serio)) {
 642                         /* Ok, old children are now gone, we are done */
 643                         break;
 644                 }
 645                 serio = serio->child;
 646         } while (serio);
 647 }
 648
 649 /*
 650  * serio_disconnect_port() unbinds a port from its driver. As a side effect
 651  * all child ports are unbound and destroyed.
 652  */
 653 static void serio_disconnect_port(struct serio *serio)
 654 {
 655         struct serio *s, *parent;
 656
 657         if (serio->child) {
 658                 /*
 659                  * Children ports should be disconnected and destroyed
 660                  * first, staring with the leaf one, since we don't want
 661                  * to do recursion
 662                  */
 663                 for (s = serio; s->child; s = s->child)
 664                         /* empty */;
 665
 666                 do {
 667                         parent = s->parent;
 668
 669                         device_release_driver(&s->dev);
 670                         serio_destroy_port(s);
 671                 } while ((s = parent) != serio);
 672         }
 673
 674         /*
 675          * Ok, no children left, now disconnect this port
 676          */
 677         device_release_driver(&serio->dev);
 678 }
 679
 680 void serio_rescan(struct serio *serio)
 681 {
 682         serio_queue_event(serio, NULL, SERIO_RESCAN_PORT);
 683 }
 684 EXPORT_SYMBOL(serio_rescan);
 685
 686 void serio_reconnect(struct serio *serio)
 687 {
 688         serio_queue_event(serio, NULL, SERIO_RECONNECT_CHAIN);
 689 }
 690 EXPORT_SYMBOL(serio_reconnect);
 691
 692 /*
 693  * Submits register request to kseriod for subsequent execution.
 694  * Note that port registration is always asynchronous.
 695  */
 696 void __serio_register_port(struct serio *serio, struct module *owner)
 697 {
 698         serio_init_port(serio);
 699         serio_queue_event(serio, owner, SERIO_REGISTER_PORT);
 700 }
 701 EXPORT_SYMBOL(__serio_register_port);
 702
 703 /*
 704  * Synchronously unregisters serio port.
 705  */
 706 void serio_unregister_port(struct serio *serio)
 707 {
 708         mutex_lock(&serio_mutex);
 709         serio_disconnect_port(serio);
 710         serio_destroy_port(serio);
 711         mutex_unlock(&serio_mutex);
 712 }
 713 EXPORT_SYMBOL(serio_unregister_port);
 714
 715 /*
 716  * Safely unregisters child port if one is present.
 717  */
 718 void serio_unregister_child_port(struct serio *serio)
 719 {
 720         mutex_lock(&serio_mutex);
 721         if (serio->child) {
 722                 serio_disconnect_port(serio->child);
 723                 serio_destroy_port(serio->child);
 724         }
 725         mutex_unlock(&serio_mutex);
 726 }
 727 EXPORT_SYMBOL(serio_unregister_child_port);
 728
 729
 730 /*
 731  * Serio driver operations
 732  */
 733
 734 static ssize_t serio_driver_show_description(struct device_driver *drv, char *buf)
 735 {
 736         struct serio_driver *driver = to_serio_driver(drv);
 737         return sprintf(buf, "%s\n", driver->description ? driver->description : "(none)");
 738 }
 739
 740 static ssize_t serio_driver_show_bind_mode(struct device_driver *drv, char *buf)
 741 {
 742         struct serio_driver *serio_drv = to_serio_driver(drv);
 743         return sprintf(buf, "%s\n", serio_drv->manual_bind ? "manual" : "auto");
 744 }
 745
 746 static ssize_t serio_driver_set_bind_mode(struct device_driver *drv, const char *buf, size_t count)
 747 {
 748         struct serio_driver *serio_drv = to_serio_driver(drv);
 749         int retval;
 750
 751         retval = count;
 752         if (!strncmp(buf, "manual", count)) {
 753                 serio_drv->manual_bind = true;
 754         } else if (!strncmp(buf, "auto", count)) {
 755                 serio_drv->manual_bind = false;
 756         } else {
 757                 retval = -EINVAL;
 758         }
 759
 760         return retval;
 761 }
 762
 763
 764 static struct driver_attribute serio_driver_attrs[] = {
 765         __ATTR(description, S_IRUGO, serio_driver_show_description, NULL),
 766         __ATTR(bind_mode, S_IWUSR | S_IRUGO,
 767                 serio_driver_show_bind_mode, serio_driver_set_bind_mode),
 768         __ATTR_NULL
 769 };
 770
 771 static int serio_driver_probe(struct device *dev)
 772 {
 773         struct serio *serio = to_serio_port(dev);
 774         struct serio_driver *drv = to_serio_driver(dev->driver);
 775
 776         return serio_connect_driver(serio, drv);
 777 }
 778
 779 static int serio_driver_remove(struct device *dev)
 780 {
 781         struct serio *serio = to_serio_port(dev);
 782
 783         serio_disconnect_driver(serio);
 784         return 0;
 785 }
 786
 787 static void serio_cleanup(struct serio *serio)
 788 {
 789         mutex_lock(&serio->drv_mutex);
 790         if (serio->drv && serio->drv->cleanup)
 791                 serio->drv->cleanup(serio);
 792         mutex_unlock(&serio->drv_mutex);
 793 }
 794
 795 static void serio_shutdown(struct device *dev)
 796 {
 797         struct serio *serio = to_serio_port(dev);
 798
 799         serio_cleanup(serio);
 800 }
 801
 802 static void serio_attach_driver(struct serio_driver *drv)
 803 {
 804         int error;
 805
 806         error = driver_attach(&drv->driver);
 807         if (error)
 808                 printk(KERN_WARNING
 809                         "serio: driver_attach() failed for %s with error %d\n",
 810                         drv->driver.name, error);
 811 }
 812
 813 int __serio_register_driver(struct serio_driver *drv, struct module *owner, const char *mod_name)
 814 {
 815         bool manual_bind = drv->manual_bind;
 816         int error;
 817
 818         drv->driver.bus = &serio_bus;
 819         drv->driver.owner = owner;
 820         drv->driver.mod_name = mod_name;
 821
 822         /*
 823          * Temporarily disable automatic binding because probing
 824          * takes long time and we are better off doing it in kseriod
 825          */
 826         drv->manual_bind = true;
 827
 828         error = driver_register(&drv->driver);
 829         if (error) {
 830                 printk(KERN_ERR
 831                         "serio: driver_register() failed for %s, error: %d\n",
 832                         drv->driver.name, error);
 833                 return error;
 834         }
 835
 836         /*
 837          * Restore original bind mode and let kseriod bind the
 838          * driver to free ports
 839          */
 840         if (!manual_bind) {
 841                 drv->manual_bind = false;
 842                 error = serio_queue_event(drv, NULL, SERIO_ATTACH_DRIVER);
 843                 if (error) {
 844                         driver_unregister(&drv->driver);
 845                         return error;
 846                 }
 847         }
 848
 849         return 0;
 850 }
 851 EXPORT_SYMBOL(__serio_register_driver);
 852
 853 void serio_unregister_driver(struct serio_driver *drv)
 854 {
 855         struct serio *serio;
 856
 857         mutex_lock(&serio_mutex);
 858
 859         drv->manual_bind = true;        /* so serio_find_driver ignores it */
 860         serio_remove_pending_events(drv);
 861
 862 start_over:
 863         list_for_each_entry(serio, &serio_list, node) {
 864                 if (serio->drv == drv) {
 865                         serio_disconnect_port(serio);
 866                         serio_find_driver(serio);
 867                         /* we could've deleted some ports, restart */
 868                         goto start_over;
 869                 }
 870         }
 871
 872         driver_unregister(&drv->driver);
 873         mutex_unlock(&serio_mutex);
 874 }
 875 EXPORT_SYMBOL(serio_unregister_driver);
 876
 877 static void serio_set_drv(struct serio *serio, struct serio_driver *drv)
 878 {
 879         serio_pause_rx(serio);
 880         serio->drv = drv;
 881         serio_continue_rx(serio);
 882 }
 883
 884 static int serio_bus_match(struct device *dev, struct device_driver *drv)
 885 {
 886         struct serio *serio = to_serio_port(dev);
 887         struct serio_driver *serio_drv = to_serio_driver(drv);
 888
 889         if (serio->manual_bind || serio_drv->manual_bind)
 890                 return 0;
 891
 892         return serio_match_port(serio_drv->id_table, serio);
 893 }
 894
 895 #ifdef CONFIG_HOTPLUG
 896
 897 #define SERIO_ADD_UEVENT_VAR(fmt, val...)                               \
 898         do {                                                            \
 899                 int err = add_uevent_var(env, fmt, val);                \
 900                 if (err)                                                \
 901                         return err;                                     \
 902         } while (0)
 903
 904 static int serio_uevent(struct device *dev, struct kobj_uevent_env *env)
 905 {
 906         struct serio *serio;
 907
 908         if (!dev)
 909                 return -ENODEV;
 910
 911         serio = to_serio_port(dev);
 912
 913         SERIO_ADD_UEVENT_VAR("SERIO_TYPE=%02x", serio->id.type);
 914         SERIO_ADD_UEVENT_VAR("SERIO_PROTO=%02x", serio->id.proto);
 915         SERIO_ADD_UEVENT_VAR("SERIO_ID=%02x", serio->id.id);
 916         SERIO_ADD_UEVENT_VAR("SERIO_EXTRA=%02x", serio->id.extra);
 917         SERIO_ADD_UEVENT_VAR("MODALIAS=serio:ty%02Xpr%02Xid%02Xex%02X",
 918                                 serio->id.type, serio->id.proto, serio->id.id, serio->id.extra);
 919
 920         return 0;
 921 }
 922 #undef SERIO_ADD_UEVENT_VAR
 923
 924 #else
 925
 926 static int serio_uevent(struct device *dev, struct kobj_uevent_env *env)
 927 {
 928         return -ENODEV;
 929 }
 930
 931 #endif /* CONFIG_HOTPLUG */
 932
 933 #ifdef CONFIG_PM
 934 static int serio_suspend(struct device *dev)
 935 {
 936         struct serio *serio = to_serio_port(dev);
 937
 938         serio_cleanup(serio);
 939
 940         return 0;
 941 }
 942
 943 static int serio_resume(struct device *dev)
 944 {
 945         struct serio *serio = to_serio_port(dev);
 946
 947         /*
 948          * Driver reconnect can take a while, so better let kseriod
 949          * deal with it.
 950          */
 951         serio_queue_event(serio, NULL, SERIO_RECONNECT_PORT);
 952
 953         return 0;
 954 }
 955
 956 static const struct dev_pm_ops serio_pm_ops = {
 957         .suspend        = serio_suspend,
 958         .resume         = serio_resume,
 959         .poweroff       = serio_suspend,
 960         .restore        = serio_resume,
 961 };
 962 #endif /* CONFIG_PM */
 963
 964 /* called from serio_driver->connect/disconnect methods under serio_mutex */
 965 int serio_open(struct serio *serio, struct serio_driver *drv)
 966 {
 967         serio_set_drv(serio, drv);
 968
 969         if (serio->open && serio->open(serio)) {
 970                 serio_set_drv(serio, NULL);
 971                 return -1;
 972         }
 973         return 0;
 974 }
 975 EXPORT_SYMBOL(serio_open);
 976
 977 /* called from serio_driver->connect/disconnect methods under serio_mutex */
 978 void serio_close(struct serio *serio)
 979 {
 980         if (serio->close)
 981                 serio->close(serio);
 982
 983         serio_set_drv(serio, NULL);
 984 }
 985 EXPORT_SYMBOL(serio_close);
 986
 987 irqreturn_t serio_interrupt(struct serio *serio,
 988                 unsigned char data, unsigned int dfl)
 989 {
 990         unsigned long flags;
 991         irqreturn_t ret = IRQ_NONE;
 992
 993         spin_lock_irqsave(&serio->lock, flags);
 994
 995         if (likely(serio->drv)) {
 996                 ret = serio->drv->interrupt(serio, data, dfl);
 997         } else if (!dfl && serio->registered) {
 998                 serio_rescan(serio);
 999                 ret = IRQ_HANDLED;
1000         }
1001
1002         spin_unlock_irqrestore(&serio->lock, flags);
1003
1004         return ret;
1005 }
1006 EXPORT_SYMBOL(serio_interrupt);
1007
1008 static struct bus_type serio_bus = {
1009         .name           = "serio",
1010         .dev_attrs      = serio_device_attrs,
1011         .drv_attrs      = serio_driver_attrs,
1012         .match          = serio_bus_match,
1013         .uevent         = serio_uevent,
1014         .probe          = serio_driver_probe,
1015         .remove         = serio_driver_remove,
1016         .shutdown       = serio_shutdown,
1017 #ifdef CONFIG_PM
1018         .pm             = &serio_pm_ops,
1019 #endif
1020 };
1021
1022 static int __init serio_init(void)
1023 {
1024         int error;
1025
1026         error = bus_register(&serio_bus);
1027         if (error) {
1028                 printk(KERN_ERR "serio: failed to register serio bus, error: %d\n", error);
1029                 return error;
1030         }
1031
1032         serio_task = kthread_run(serio_thread, NULL, "kseriod");
1033         if (IS_ERR(serio_task)) {
1034                 bus_unregister(&serio_bus);
1035                 error = PTR_ERR(serio_task);
1036                 printk(KERN_ERR "serio: Failed to start kseriod, error: %d\n", error);
1037                 return error;
1038         }
1039
1040         return 0;
1041 }
1042
1043 static void __exit serio_exit(void)
1044 {
1045         bus_unregister(&serio_bus);
1046         kthread_stop(serio_task);
1047 }
1048
1049 subsys_initcall(serio_init);
1050 module_exit(serio_exit);