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         while ((event = serio_get_event())) {
 288
 289                 switch (event->type) {
 290                         case SERIO_REGISTER_PORT:
 291                                 serio_add_port(event->object);
 292                                 break;
 293
 294                         case SERIO_RECONNECT_PORT:
 295                                 serio_reconnect_port(event->object);
 296                                 break;
 297
 298                         case SERIO_RESCAN_PORT:
 299                                 serio_disconnect_port(event->object);
 300                                 serio_find_driver(event->object);
 301                                 break;
 302
 303                         case SERIO_RECONNECT_CHAIN:
 304                                 serio_reconnect_chain(event->object);
 305                                 break;
 306
 307                         case SERIO_ATTACH_DRIVER:
 308                                 serio_attach_driver(event->object);
 309                                 break;
 310
 311                         default:
 312                                 break;
 313                 }
 314
 315                 serio_remove_duplicate_events(event);
 316                 serio_free_event(event);
 317         }
 318
 319         mutex_unlock(&serio_mutex);
 320 }
 321
 322 /*
 323  * Remove all events that have been submitted for a given
 324  * object, be it serio port or driver.
 325  */
 326 static void serio_remove_pending_events(void *object)
 327 {
 328         struct list_head *node, *next;
 329         struct serio_event *event;
 330         unsigned long flags;
 331
 332         spin_lock_irqsave(&serio_event_lock, flags);
 333
 334         list_for_each_safe(node, next, &serio_event_list) {
 335                 event = list_entry(node, struct serio_event, node);
 336                 if (event->object == object) {
 337                         list_del_init(node);
 338                         serio_free_event(event);
 339                 }
 340         }
 341
 342         spin_unlock_irqrestore(&serio_event_lock, flags);
 343 }
 344
 345 /*
 346  * Destroy child serio port (if any) that has not been fully registered yet.
 347  *
 348  * Note that we rely on the fact that port can have only one child and therefore
 349  * only one child registration request can be pending. Additionally, children
 350  * are registered by driver's connect() handler so there can't be a grandchild
 351  * pending registration together with a child.
 352  */
 353 static struct serio *serio_get_pending_child(struct serio *parent)
 354 {
 355         struct serio_event *event;
 356         struct serio *serio, *child = NULL;
 357         unsigned long flags;
 358
 359         spin_lock_irqsave(&serio_event_lock, flags);
 360
 361         list_for_each_entry(event, &serio_event_list, node) {
 362                 if (event->type == SERIO_REGISTER_PORT) {
 363                         serio = event->object;
 364                         if (serio->parent == parent) {
 365                                 child = serio;
 366                                 break;
 367                         }
 368                 }
 369         }
 370
 371         spin_unlock_irqrestore(&serio_event_lock, flags);
 372         return child;
 373 }
 374
 375 static int serio_thread(void *nothing)
 376 {
 377         do {
 378                 serio_handle_event();
 379                 wait_event_interruptible(serio_wait,
 380                         kthread_should_stop() || !list_empty(&serio_event_list));
 381         } while (!kthread_should_stop());
 382
 383         printk(KERN_DEBUG "serio: kseriod exiting\n");
 384         return 0;
 385 }
 386
 387
 388 /*
 389  * Serio port operations
 390  */
 391
 392 static ssize_t serio_show_description(struct device *dev, struct device_attribute *attr, char *buf)
 393 {
 394         struct serio *serio = to_serio_port(dev);
 395         return sprintf(buf, "%s\n", serio->name);
 396 }
 397
 398 static ssize_t serio_show_modalias(struct device *dev, struct device_attribute *attr, char *buf)
 399 {
 400         struct serio *serio = to_serio_port(dev);
 401
 402         return sprintf(buf, "serio:ty%02Xpr%02Xid%02Xex%02X\n",
 403                         serio->id.type, serio->id.proto, serio->id.id, serio->id.extra);
 404 }
 405
 406 static ssize_t serio_show_id_type(struct device *dev, struct device_attribute *attr, char *buf)
 407 {
 408         struct serio *serio = to_serio_port(dev);
 409         return sprintf(buf, "%02x\n", serio->id.type);
 410 }
 411
 412 static ssize_t serio_show_id_proto(struct device *dev, struct device_attribute *attr, char *buf)
 413 {
 414         struct serio *serio = to_serio_port(dev);
 415         return sprintf(buf, "%02x\n", serio->id.proto);
 416 }
 417
 418 static ssize_t serio_show_id_id(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.id);
 422 }
 423
 424 static ssize_t serio_show_id_extra(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.extra);
 428 }
 429
 430 static DEVICE_ATTR(type, S_IRUGO, serio_show_id_type, NULL);
 431 static DEVICE_ATTR(proto, S_IRUGO, serio_show_id_proto, NULL);
 432 static DEVICE_ATTR(id, S_IRUGO, serio_show_id_id, NULL);
 433 static DEVICE_ATTR(extra, S_IRUGO, serio_show_id_extra, NULL);
 434
 435 static struct attribute *serio_device_id_attrs[] = {
 436         &dev_attr_type.attr,
 437         &dev_attr_proto.attr,
 438         &dev_attr_id.attr,
 439         &dev_attr_extra.attr,
 440         NULL
 441 };
 442
 443 static struct attribute_group serio_id_attr_group = {
 444         .name   = "id",
 445         .attrs  = serio_device_id_attrs,
 446 };
 447
 448 static ssize_t serio_rebind_driver(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
 449 {
 450         struct serio *serio = to_serio_port(dev);
 451         struct device_driver *drv;
 452         int error;
 453
 454         error = mutex_lock_interruptible(&serio_mutex);
 455         if (error)
 456                 return error;
 457
 458         if (!strncmp(buf, "none", count)) {
 459                 serio_disconnect_port(serio);
 460         } else if (!strncmp(buf, "reconnect", count)) {
 461                 serio_reconnect_chain(serio);
 462         } else if (!strncmp(buf, "rescan", count)) {
 463                 serio_disconnect_port(serio);
 464                 serio_find_driver(serio);
 465         } else if ((drv = driver_find(buf, &serio_bus)) != NULL) {
 466                 serio_disconnect_port(serio);
 467                 error = serio_bind_driver(serio, to_serio_driver(drv));
 468                 put_driver(drv);
 469         } else {
 470                 error = -EINVAL;
 471         }
 472
 473         mutex_unlock(&serio_mutex);
 474
 475         return error ? error : count;
 476 }
 477
 478 static ssize_t serio_show_bind_mode(struct device *dev, struct device_attribute *attr, char *buf)
 479 {
 480         struct serio *serio = to_serio_port(dev);
 481         return sprintf(buf, "%s\n", serio->manual_bind ? "manual" : "auto");
 482 }
 483
 484 static ssize_t serio_set_bind_mode(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
 485 {
 486         struct serio *serio = to_serio_port(dev);
 487         int retval;
 488
 489         retval = count;
 490         if (!strncmp(buf, "manual", count)) {
 491                 serio->manual_bind = true;
 492         } else if (!strncmp(buf, "auto", count)) {
 493                 serio->manual_bind = false;
 494         } else {
 495                 retval = -EINVAL;
 496         }
 497
 498         return retval;
 499 }
 500
 501 static struct device_attribute serio_device_attrs[] = {
 502         __ATTR(description, S_IRUGO, serio_show_description, NULL),
 503         __ATTR(modalias, S_IRUGO, serio_show_modalias, NULL),
 504         __ATTR(drvctl, S_IWUSR, NULL, serio_rebind_driver),
 505         __ATTR(bind_mode, S_IWUSR | S_IRUGO, serio_show_bind_mode, serio_set_bind_mode),
 506         __ATTR_NULL
 507 };
 508
 509
 510 static void serio_release_port(struct device *dev)
 511 {
 512         struct serio *serio = to_serio_port(dev);
 513
 514         kfree(serio);
 515         module_put(THIS_MODULE);
 516 }
 517
 518 /*
 519  * Prepare serio port for registration.
 520  */
 521 static void serio_init_port(struct serio *serio)
 522 {
 523         static atomic_t serio_no = ATOMIC_INIT(0);
 524
 525         __module_get(THIS_MODULE);
 526
 527         INIT_LIST_HEAD(&serio->node);
 528         spin_lock_init(&serio->lock);
 529         mutex_init(&serio->drv_mutex);
 530         device_initialize(&serio->dev);
 531         dev_set_name(&serio->dev, "serio%ld",
 532                         (long)atomic_inc_return(&serio_no) - 1);
 533         serio->dev.bus = &serio_bus;
 534         serio->dev.release = serio_release_port;
 535         if (serio->parent) {
 536                 serio->dev.parent = &serio->parent->dev;
 537                 serio->depth = serio->parent->depth + 1;
 538         } else
 539                 serio->depth = 0;
 540         lockdep_set_subclass(&serio->lock, serio->depth);
 541 }
 542
 543 /*
 544  * Complete serio port registration.
 545  * Driver core will attempt to find appropriate driver for the port.
 546  */
 547 static void serio_add_port(struct serio *serio)
 548 {
 549         int error;
 550
 551         if (serio->parent) {
 552                 serio_pause_rx(serio->parent);
 553                 serio->parent->child = serio;
 554                 serio_continue_rx(serio->parent);
 555         }
 556
 557         list_add_tail(&serio->node, &serio_list);
 558         if (serio->start)
 559                 serio->start(serio);
 560         error = device_add(&serio->dev);
 561         if (error)
 562                 printk(KERN_ERR
 563                         "serio: device_add() failed for %s (%s), error: %d\n",
 564                         serio->phys, serio->name, error);
 565         else {
 566                 serio->registered = true;
 567                 error = sysfs_create_group(&serio->dev.kobj, &serio_id_attr_group);
 568                 if (error)
 569                         printk(KERN_ERR
 570                                 "serio: sysfs_create_group() failed for %s (%s), error: %d\n",
 571                                 serio->phys, serio->name, error);
 572         }
 573 }
 574
 575 /*
 576  * serio_destroy_port() completes deregistration process and removes
 577  * port from the system
 578  */
 579 static void serio_destroy_port(struct serio *serio)
 580 {
 581         struct serio *child;
 582
 583         child = serio_get_pending_child(serio);
 584         if (child) {
 585                 serio_remove_pending_events(child);
 586                 put_device(&child->dev);
 587         }
 588
 589         if (serio->stop)
 590                 serio->stop(serio);
 591
 592         if (serio->parent) {
 593                 serio_pause_rx(serio->parent);
 594                 serio->parent->child = NULL;
 595                 serio_continue_rx(serio->parent);
 596                 serio->parent = NULL;
 597         }
 598
 599         if (serio->registered) {
 600                 sysfs_remove_group(&serio->dev.kobj, &serio_id_attr_group);
 601                 device_del(&serio->dev);
 602                 serio->registered = false;
 603         }
 604
 605         list_del_init(&serio->node);
 606         serio_remove_pending_events(serio);
 607         put_device(&serio->dev);
 608 }
 609
 610 /*
 611  * Reconnect serio port (re-initialize attached device).
 612  * If reconnect fails (old device is no longer attached or
 613  * there was no device to begin with) we do full rescan in
 614  * hope of finding a driver for the port.
 615  */
 616 static int serio_reconnect_port(struct serio *serio)
 617 {
 618         int error = serio_reconnect_driver(serio);
 619
 620         if (error) {
 621                 serio_disconnect_port(serio);
 622                 serio_find_driver(serio);
 623         }
 624
 625         return error;
 626 }
 627
 628 /*
 629  * Reconnect serio port and all its children (re-initialize attached devices)
 630  */
 631 static void serio_reconnect_chain(struct serio *serio)
 632 {
 633         do {
 634                 if (serio_reconnect_port(serio)) {
 635                         /* Ok, old children are now gone, we are done */
 636                         break;
 637                 }
 638                 serio = serio->child;
 639         } while (serio);
 640 }
 641
 642 /*
 643  * serio_disconnect_port() unbinds a port from its driver. As a side effect
 644  * all child ports are unbound and destroyed.
 645  */
 646 static void serio_disconnect_port(struct serio *serio)
 647 {
 648         struct serio *s, *parent;
 649
 650         if (serio->child) {
 651                 /*
 652                  * Children ports should be disconnected and destroyed
 653                  * first, staring with the leaf one, since we don't want
 654                  * to do recursion
 655                  */
 656                 for (s = serio; s->child; s = s->child)
 657                         /* empty */;
 658
 659                 do {
 660                         parent = s->parent;
 661
 662                         device_release_driver(&s->dev);
 663                         serio_destroy_port(s);
 664                 } while ((s = parent) != serio);
 665         }
 666
 667         /*
 668          * Ok, no children left, now disconnect this port
 669          */
 670         device_release_driver(&serio->dev);
 671 }
 672
 673 void serio_rescan(struct serio *serio)
 674 {
 675         serio_queue_event(serio, NULL, SERIO_RESCAN_PORT);
 676 }
 677 EXPORT_SYMBOL(serio_rescan);
 678
 679 void serio_reconnect(struct serio *serio)
 680 {
 681         serio_queue_event(serio, NULL, SERIO_RECONNECT_CHAIN);
 682 }
 683 EXPORT_SYMBOL(serio_reconnect);
 684
 685 /*
 686  * Submits register request to kseriod for subsequent execution.
 687  * Note that port registration is always asynchronous.
 688  */
 689 void __serio_register_port(struct serio *serio, struct module *owner)
 690 {
 691         serio_init_port(serio);
 692         serio_queue_event(serio, owner, SERIO_REGISTER_PORT);
 693 }
 694 EXPORT_SYMBOL(__serio_register_port);
 695
 696 /*
 697  * Synchronously unregisters serio port.
 698  */
 699 void serio_unregister_port(struct serio *serio)
 700 {
 701         mutex_lock(&serio_mutex);
 702         serio_disconnect_port(serio);
 703         serio_destroy_port(serio);
 704         mutex_unlock(&serio_mutex);
 705 }
 706 EXPORT_SYMBOL(serio_unregister_port);
 707
 708 /*
 709  * Safely unregisters child port if one is present.
 710  */
 711 void serio_unregister_child_port(struct serio *serio)
 712 {
 713         mutex_lock(&serio_mutex);
 714         if (serio->child) {
 715                 serio_disconnect_port(serio->child);
 716                 serio_destroy_port(serio->child);
 717         }
 718         mutex_unlock(&serio_mutex);
 719 }
 720 EXPORT_SYMBOL(serio_unregister_child_port);
 721
 722
 723 /*
 724  * Serio driver operations
 725  */
 726
 727 static ssize_t serio_driver_show_description(struct device_driver *drv, char *buf)
 728 {
 729         struct serio_driver *driver = to_serio_driver(drv);
 730         return sprintf(buf, "%s\n", driver->description ? driver->description : "(none)");
 731 }
 732
 733 static ssize_t serio_driver_show_bind_mode(struct device_driver *drv, char *buf)
 734 {
 735         struct serio_driver *serio_drv = to_serio_driver(drv);
 736         return sprintf(buf, "%s\n", serio_drv->manual_bind ? "manual" : "auto");
 737 }
 738
 739 static ssize_t serio_driver_set_bind_mode(struct device_driver *drv, const char *buf, size_t count)
 740 {
 741         struct serio_driver *serio_drv = to_serio_driver(drv);
 742         int retval;
 743
 744         retval = count;
 745         if (!strncmp(buf, "manual", count)) {
 746                 serio_drv->manual_bind = true;
 747         } else if (!strncmp(buf, "auto", count)) {
 748                 serio_drv->manual_bind = false;
 749         } else {
 750                 retval = -EINVAL;
 751         }
 752
 753         return retval;
 754 }
 755
 756
 757 static struct driver_attribute serio_driver_attrs[] = {
 758         __ATTR(description, S_IRUGO, serio_driver_show_description, NULL),
 759         __ATTR(bind_mode, S_IWUSR | S_IRUGO,
 760                 serio_driver_show_bind_mode, serio_driver_set_bind_mode),
 761         __ATTR_NULL
 762 };
 763
 764 static int serio_driver_probe(struct device *dev)
 765 {
 766         struct serio *serio = to_serio_port(dev);
 767         struct serio_driver *drv = to_serio_driver(dev->driver);
 768
 769         return serio_connect_driver(serio, drv);
 770 }
 771
 772 static int serio_driver_remove(struct device *dev)
 773 {
 774         struct serio *serio = to_serio_port(dev);
 775
 776         serio_disconnect_driver(serio);
 777         return 0;
 778 }
 779
 780 static void serio_cleanup(struct serio *serio)
 781 {
 782         mutex_lock(&serio->drv_mutex);
 783         if (serio->drv && serio->drv->cleanup)
 784                 serio->drv->cleanup(serio);
 785         mutex_unlock(&serio->drv_mutex);
 786 }
 787
 788 static void serio_shutdown(struct device *dev)
 789 {
 790         struct serio *serio = to_serio_port(dev);
 791
 792         serio_cleanup(serio);
 793 }
 794
 795 static void serio_attach_driver(struct serio_driver *drv)
 796 {
 797         int error;
 798
 799         error = driver_attach(&drv->driver);
 800         if (error)
 801                 printk(KERN_WARNING
 802                         "serio: driver_attach() failed for %s with error %d\n",
 803                         drv->driver.name, error);
 804 }
 805
 806 int __serio_register_driver(struct serio_driver *drv, struct module *owner, const char *mod_name)
 807 {
 808         bool manual_bind = drv->manual_bind;
 809         int error;
 810
 811         drv->driver.bus = &serio_bus;
 812         drv->driver.owner = owner;
 813         drv->driver.mod_name = mod_name;
 814
 815         /*
 816          * Temporarily disable automatic binding because probing
 817          * takes long time and we are better off doing it in kseriod
 818          */
 819         drv->manual_bind = true;
 820
 821         error = driver_register(&drv->driver);
 822         if (error) {
 823                 printk(KERN_ERR
 824                         "serio: driver_register() failed for %s, error: %d\n",
 825                         drv->driver.name, error);
 826                 return error;
 827         }
 828
 829         /*
 830          * Restore original bind mode and let kseriod bind the
 831          * driver to free ports
 832          */
 833         if (!manual_bind) {
 834                 drv->manual_bind = false;
 835                 error = serio_queue_event(drv, NULL, SERIO_ATTACH_DRIVER);
 836                 if (error) {
 837                         driver_unregister(&drv->driver);
 838                         return error;
 839                 }
 840         }
 841
 842         return 0;
 843 }
 844 EXPORT_SYMBOL(__serio_register_driver);
 845
 846 void serio_unregister_driver(struct serio_driver *drv)
 847 {
 848         struct serio *serio;
 849
 850         mutex_lock(&serio_mutex);
 851
 852         drv->manual_bind = true;        /* so serio_find_driver ignores it */
 853         serio_remove_pending_events(drv);
 854
 855 start_over:
 856         list_for_each_entry(serio, &serio_list, node) {
 857                 if (serio->drv == drv) {
 858                         serio_disconnect_port(serio);
 859                         serio_find_driver(serio);
 860                         /* we could've deleted some ports, restart */
 861                         goto start_over;
 862                 }
 863         }
 864
 865         driver_unregister(&drv->driver);
 866         mutex_unlock(&serio_mutex);
 867 }
 868 EXPORT_SYMBOL(serio_unregister_driver);
 869
 870 static void serio_set_drv(struct serio *serio, struct serio_driver *drv)
 871 {
 872         serio_pause_rx(serio);
 873         serio->drv = drv;
 874         serio_continue_rx(serio);
 875 }
 876
 877 static int serio_bus_match(struct device *dev, struct device_driver *drv)
 878 {
 879         struct serio *serio = to_serio_port(dev);
 880         struct serio_driver *serio_drv = to_serio_driver(drv);
 881
 882         if (serio->manual_bind || serio_drv->manual_bind)
 883                 return 0;
 884
 885         return serio_match_port(serio_drv->id_table, serio);
 886 }
 887
 888 #ifdef CONFIG_HOTPLUG
 889
 890 #define SERIO_ADD_UEVENT_VAR(fmt, val...)                               \
 891         do {                                                            \
 892                 int err = add_uevent_var(env, fmt, val);                \
 893                 if (err)                                                \
 894                         return err;                                     \
 895         } while (0)
 896
 897 static int serio_uevent(struct device *dev, struct kobj_uevent_env *env)
 898 {
 899         struct serio *serio;
 900
 901         if (!dev)
 902                 return -ENODEV;
 903
 904         serio = to_serio_port(dev);
 905
 906         SERIO_ADD_UEVENT_VAR("SERIO_TYPE=%02x", serio->id.type);
 907         SERIO_ADD_UEVENT_VAR("SERIO_PROTO=%02x", serio->id.proto);
 908         SERIO_ADD_UEVENT_VAR("SERIO_ID=%02x", serio->id.id);
 909         SERIO_ADD_UEVENT_VAR("SERIO_EXTRA=%02x", serio->id.extra);
 910         SERIO_ADD_UEVENT_VAR("MODALIAS=serio:ty%02Xpr%02Xid%02Xex%02X",
 911                                 serio->id.type, serio->id.proto, serio->id.id, serio->id.extra);
 912
 913         return 0;
 914 }
 915 #undef SERIO_ADD_UEVENT_VAR
 916
 917 #else
 918
 919 static int serio_uevent(struct device *dev, struct kobj_uevent_env *env)
 920 {
 921         return -ENODEV;
 922 }
 923
 924 #endif /* CONFIG_HOTPLUG */
 925
 926 #ifdef CONFIG_PM
 927 static int serio_suspend(struct device *dev)
 928 {
 929         struct serio *serio = to_serio_port(dev);
 930
 931         serio_cleanup(serio);
 932
 933         return 0;
 934 }
 935
 936 static int serio_resume(struct device *dev)
 937 {
 938         struct serio *serio = to_serio_port(dev);
 939
 940         /*
 941          * Driver reconnect can take a while, so better let kseriod
 942          * deal with it.
 943          */
 944         serio_queue_event(serio, NULL, SERIO_RECONNECT_PORT);
 945
 946         return 0;
 947 }
 948
 949 static const struct dev_pm_ops serio_pm_ops = {
 950         .suspend        = serio_suspend,
 951         .resume         = serio_resume,
 952         .poweroff       = serio_suspend,
 953         .restore        = serio_resume,
 954 };
 955 #endif /* CONFIG_PM */
 956
 957 /* called from serio_driver->connect/disconnect methods under serio_mutex */
 958 int serio_open(struct serio *serio, struct serio_driver *drv)
 959 {
 960         serio_set_drv(serio, drv);
 961
 962         if (serio->open && serio->open(serio)) {
 963                 serio_set_drv(serio, NULL);
 964                 return -1;
 965         }
 966         return 0;
 967 }
 968 EXPORT_SYMBOL(serio_open);
 969
 970 /* called from serio_driver->connect/disconnect methods under serio_mutex */
 971 void serio_close(struct serio *serio)
 972 {
 973         if (serio->close)
 974                 serio->close(serio);
 975
 976         serio_set_drv(serio, NULL);
 977 }
 978 EXPORT_SYMBOL(serio_close);
 979
 980 irqreturn_t serio_interrupt(struct serio *serio,
 981                 unsigned char data, unsigned int dfl)
 982 {
 983         unsigned long flags;
 984         irqreturn_t ret = IRQ_NONE;
 985
 986         spin_lock_irqsave(&serio->lock, flags);
 987
 988         if (likely(serio->drv)) {
 989                 ret = serio->drv->interrupt(serio, data, dfl);
 990         } else if (!dfl && serio->registered) {
 991                 serio_rescan(serio);
 992                 ret = IRQ_HANDLED;
 993         }
 994
 995         spin_unlock_irqrestore(&serio->lock, flags);
 996
 997         return ret;
 998 }
 999 EXPORT_SYMBOL(serio_interrupt);
1000
1001 static struct bus_type serio_bus = {
1002         .name           = "serio",
1003         .dev_attrs      = serio_device_attrs,
1004         .drv_attrs      = serio_driver_attrs,
1005         .match          = serio_bus_match,
1006         .uevent         = serio_uevent,
1007         .probe          = serio_driver_probe,
1008         .remove         = serio_driver_remove,
1009         .shutdown       = serio_shutdown,
1010 #ifdef CONFIG_PM
1011         .pm             = &serio_pm_ops,
1012 #endif
1013 };
1014
1015 static int __init serio_init(void)
1016 {
1017         int error;
1018
1019         error = bus_register(&serio_bus);
1020         if (error) {
1021                 printk(KERN_ERR "serio: failed to register serio bus, error: %d\n", error);
1022                 return error;
1023         }
1024
1025         serio_task = kthread_run(serio_thread, NULL, "kseriod");
1026         if (IS_ERR(serio_task)) {
1027                 bus_unregister(&serio_bus);
1028                 error = PTR_ERR(serio_task);
1029                 printk(KERN_ERR "serio: Failed to start kseriod, error: %d\n", error);
1030                 return error;
1031         }
1032
1033         return 0;
1034 }
1035
1036 static void __exit serio_exit(void)
1037 {
1038         bus_unregister(&serio_bus);
1039         kthread_stop(serio_task);
1040 }
1041
1042 subsys_initcall(serio_init);
1043 module_exit(serio_exit);