Input: serio/gameport - check whether driver core calls succeeded
[linux-2.6.git] / drivers / input / gameport / gameport.c
1 /*
2  * Generic gameport layer
3  *
4  * Copyright (c) 1999-2002 Vojtech Pavlik
5  * Copyright (c) 2005 Dmitry Torokhov
6  */
7
8 /*
9  * This program is free software; you can redistribute it and/or modify it
10  * under the terms of the GNU General Public License version 2 as published by
11  * the Free Software Foundation.
12  */
13
14 #include <linux/stddef.h>
15 #include <linux/module.h>
16 #include <linux/ioport.h>
17 #include <linux/init.h>
18 #include <linux/gameport.h>
19 #include <linux/wait.h>
20 #include <linux/sched.h>
21 #include <linux/slab.h>
22 #include <linux/delay.h>
23 #include <linux/kthread.h>
24 #include <linux/sched.h>        /* HZ */
25 #include <linux/mutex.h>
26
27 /*#include <asm/io.h>*/
28
29 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
30 MODULE_DESCRIPTION("Generic gameport layer");
31 MODULE_LICENSE("GPL");
32
33 EXPORT_SYMBOL(__gameport_register_port);
34 EXPORT_SYMBOL(gameport_unregister_port);
35 EXPORT_SYMBOL(__gameport_register_driver);
36 EXPORT_SYMBOL(gameport_unregister_driver);
37 EXPORT_SYMBOL(gameport_open);
38 EXPORT_SYMBOL(gameport_close);
39 EXPORT_SYMBOL(gameport_rescan);
40 EXPORT_SYMBOL(gameport_cooked_read);
41 EXPORT_SYMBOL(gameport_set_name);
42 EXPORT_SYMBOL(gameport_set_phys);
43 EXPORT_SYMBOL(gameport_start_polling);
44 EXPORT_SYMBOL(gameport_stop_polling);
45
46 /*
47  * gameport_mutex protects entire gameport subsystem and is taken
48  * every time gameport port or driver registrered or unregistered.
49  */
50 static DEFINE_MUTEX(gameport_mutex);
51
52 static LIST_HEAD(gameport_list);
53
54 static struct bus_type gameport_bus;
55
56 static void gameport_add_driver(struct gameport_driver *drv);
57 static void gameport_add_port(struct gameport *gameport);
58 static void gameport_destroy_port(struct gameport *gameport);
59 static void gameport_reconnect_port(struct gameport *gameport);
60 static void gameport_disconnect_port(struct gameport *gameport);
61
62 #if defined(__i386__)
63
64 #include <asm/i8253.h>
65
66 #define DELTA(x,y)      ((y)-(x)+((y)<(x)?1193182/HZ:0))
67 #define GET_TIME(x)     do { x = get_time_pit(); } while (0)
68
69 static unsigned int get_time_pit(void)
70 {
71         unsigned long flags;
72         unsigned int count;
73
74         spin_lock_irqsave(&i8253_lock, flags);
75         outb_p(0x00, 0x43);
76         count = inb_p(0x40);
77         count |= inb_p(0x40) << 8;
78         spin_unlock_irqrestore(&i8253_lock, flags);
79
80         return count;
81 }
82
83 #endif
84
85
86
87 /*
88  * gameport_measure_speed() measures the gameport i/o speed.
89  */
90
91 static int gameport_measure_speed(struct gameport *gameport)
92 {
93 #if defined(__i386__)
94
95         unsigned int i, t, t1, t2, t3, tx;
96         unsigned long flags;
97
98         if (gameport_open(gameport, NULL, GAMEPORT_MODE_RAW))
99                 return 0;
100
101         tx = 1 << 30;
102
103         for(i = 0; i < 50; i++) {
104                 local_irq_save(flags);
105                 GET_TIME(t1);
106                 for (t = 0; t < 50; t++) gameport_read(gameport);
107                 GET_TIME(t2);
108                 GET_TIME(t3);
109                 local_irq_restore(flags);
110                 udelay(i * 10);
111                 if ((t = DELTA(t2,t1) - DELTA(t3,t2)) < tx) tx = t;
112         }
113
114         gameport_close(gameport);
115         return 59659 / (tx < 1 ? 1 : tx);
116
117 #elif defined (__x86_64__)
118
119         unsigned int i, t;
120         unsigned long tx, t1, t2, flags;
121
122         if (gameport_open(gameport, NULL, GAMEPORT_MODE_RAW))
123                 return 0;
124
125         tx = 1 << 30;
126
127         for(i = 0; i < 50; i++) {
128                 local_irq_save(flags);
129                 rdtscl(t1);
130                 for (t = 0; t < 50; t++) gameport_read(gameport);
131                 rdtscl(t2);
132                 local_irq_restore(flags);
133                 udelay(i * 10);
134                 if (t2 - t1 < tx) tx = t2 - t1;
135         }
136
137         gameport_close(gameport);
138         return (cpu_data[raw_smp_processor_id()].loops_per_jiffy * (unsigned long)HZ / (1000 / 50)) / (tx < 1 ? 1 : tx);
139
140 #else
141
142         unsigned int j, t = 0;
143
144         if (gameport_open(gameport, NULL, GAMEPORT_MODE_RAW))
145                 return 0;
146
147         j = jiffies; while (j == jiffies);
148         j = jiffies; while (j == jiffies) { t++; gameport_read(gameport); }
149
150         gameport_close(gameport);
151         return t * HZ / 1000;
152
153 #endif
154 }
155
156 void gameport_start_polling(struct gameport *gameport)
157 {
158         spin_lock(&gameport->timer_lock);
159
160         if (!gameport->poll_cnt++) {
161                 BUG_ON(!gameport->poll_handler);
162                 BUG_ON(!gameport->poll_interval);
163                 mod_timer(&gameport->poll_timer, jiffies + msecs_to_jiffies(gameport->poll_interval));
164         }
165
166         spin_unlock(&gameport->timer_lock);
167 }
168
169 void gameport_stop_polling(struct gameport *gameport)
170 {
171         spin_lock(&gameport->timer_lock);
172
173         if (!--gameport->poll_cnt)
174                 del_timer(&gameport->poll_timer);
175
176         spin_unlock(&gameport->timer_lock);
177 }
178
179 static void gameport_run_poll_handler(unsigned long d)
180 {
181         struct gameport *gameport = (struct gameport *)d;
182
183         gameport->poll_handler(gameport);
184         if (gameport->poll_cnt)
185                 mod_timer(&gameport->poll_timer, jiffies + msecs_to_jiffies(gameport->poll_interval));
186 }
187
188 /*
189  * Basic gameport -> driver core mappings
190  */
191
192 static void gameport_bind_driver(struct gameport *gameport, struct gameport_driver *drv)
193 {
194         down_write(&gameport_bus.subsys.rwsem);
195
196         gameport->dev.driver = &drv->driver;
197         if (drv->connect(gameport, drv)) {
198                 gameport->dev.driver = NULL;
199                 goto out;
200         }
201         device_bind_driver(&gameport->dev);
202 out:
203         up_write(&gameport_bus.subsys.rwsem);
204 }
205
206 static void gameport_release_driver(struct gameport *gameport)
207 {
208         down_write(&gameport_bus.subsys.rwsem);
209         device_release_driver(&gameport->dev);
210         up_write(&gameport_bus.subsys.rwsem);
211 }
212
213 static void gameport_find_driver(struct gameport *gameport)
214 {
215         int error;
216
217         down_write(&gameport_bus.subsys.rwsem);
218         error = device_attach(&gameport->dev);
219         if (error < 0)
220                 printk(KERN_WARNING
221                         "gameport: device_attach() failed for %s (%s), error: %d\n",
222                         gameport->phys, gameport->name, error);
223         up_write(&gameport_bus.subsys.rwsem);
224 }
225
226
227 /*
228  * Gameport event processing.
229  */
230
231 enum gameport_event_type {
232         GAMEPORT_RESCAN,
233         GAMEPORT_RECONNECT,
234         GAMEPORT_REGISTER_PORT,
235         GAMEPORT_REGISTER_DRIVER,
236 };
237
238 struct gameport_event {
239         enum gameport_event_type type;
240         void *object;
241         struct module *owner;
242         struct list_head node;
243 };
244
245 static DEFINE_SPINLOCK(gameport_event_lock);    /* protects gameport_event_list */
246 static LIST_HEAD(gameport_event_list);
247 static DECLARE_WAIT_QUEUE_HEAD(gameport_wait);
248 static struct task_struct *gameport_task;
249
250 static void gameport_queue_event(void *object, struct module *owner,
251                               enum gameport_event_type event_type)
252 {
253         unsigned long flags;
254         struct gameport_event *event;
255
256         spin_lock_irqsave(&gameport_event_lock, flags);
257
258         /*
259          * Scan event list for the other events for the same gameport port,
260          * starting with the most recent one. If event is the same we
261          * do not need add new one. If event is of different type we
262          * need to add this event and should not look further because
263          * we need to preseve sequence of distinct events.
264          */
265         list_for_each_entry_reverse(event, &gameport_event_list, node) {
266                 if (event->object == object) {
267                         if (event->type == event_type)
268                                 goto out;
269                         break;
270                 }
271         }
272
273         if ((event = kmalloc(sizeof(struct gameport_event), GFP_ATOMIC))) {
274                 if (!try_module_get(owner)) {
275                         printk(KERN_WARNING "gameport: Can't get module reference, dropping event %d\n", event_type);
276                         kfree(event);
277                         goto out;
278                 }
279
280                 event->type = event_type;
281                 event->object = object;
282                 event->owner = owner;
283
284                 list_add_tail(&event->node, &gameport_event_list);
285                 wake_up(&gameport_wait);
286         } else {
287                 printk(KERN_ERR "gameport: Not enough memory to queue event %d\n", event_type);
288         }
289 out:
290         spin_unlock_irqrestore(&gameport_event_lock, flags);
291 }
292
293 static void gameport_free_event(struct gameport_event *event)
294 {
295         module_put(event->owner);
296         kfree(event);
297 }
298
299 static void gameport_remove_duplicate_events(struct gameport_event *event)
300 {
301         struct list_head *node, *next;
302         struct gameport_event *e;
303         unsigned long flags;
304
305         spin_lock_irqsave(&gameport_event_lock, flags);
306
307         list_for_each_safe(node, next, &gameport_event_list) {
308                 e = list_entry(node, struct gameport_event, node);
309                 if (event->object == e->object) {
310                         /*
311                          * If this event is of different type we should not
312                          * look further - we only suppress duplicate events
313                          * that were sent back-to-back.
314                          */
315                         if (event->type != e->type)
316                                 break;
317
318                         list_del_init(node);
319                         gameport_free_event(e);
320                 }
321         }
322
323         spin_unlock_irqrestore(&gameport_event_lock, flags);
324 }
325
326 static struct gameport_event *gameport_get_event(void)
327 {
328         struct gameport_event *event;
329         struct list_head *node;
330         unsigned long flags;
331
332         spin_lock_irqsave(&gameport_event_lock, flags);
333
334         if (list_empty(&gameport_event_list)) {
335                 spin_unlock_irqrestore(&gameport_event_lock, flags);
336                 return NULL;
337         }
338
339         node = gameport_event_list.next;
340         event = list_entry(node, struct gameport_event, node);
341         list_del_init(node);
342
343         spin_unlock_irqrestore(&gameport_event_lock, flags);
344
345         return event;
346 }
347
348 static void gameport_handle_event(void)
349 {
350         struct gameport_event *event;
351
352         mutex_lock(&gameport_mutex);
353
354         /*
355          * Note that we handle only one event here to give swsusp
356          * a chance to freeze kgameportd thread. Gameport events
357          * should be pretty rare so we are not concerned about
358          * taking performance hit.
359          */
360         if ((event = gameport_get_event())) {
361
362                 switch (event->type) {
363                         case GAMEPORT_REGISTER_PORT:
364                                 gameport_add_port(event->object);
365                                 break;
366
367                         case GAMEPORT_RECONNECT:
368                                 gameport_reconnect_port(event->object);
369                                 break;
370
371                         case GAMEPORT_RESCAN:
372                                 gameport_disconnect_port(event->object);
373                                 gameport_find_driver(event->object);
374                                 break;
375
376                         case GAMEPORT_REGISTER_DRIVER:
377                                 gameport_add_driver(event->object);
378                                 break;
379
380                         default:
381                                 break;
382                 }
383
384                 gameport_remove_duplicate_events(event);
385                 gameport_free_event(event);
386         }
387
388         mutex_unlock(&gameport_mutex);
389 }
390
391 /*
392  * Remove all events that have been submitted for a given gameport port.
393  */
394 static void gameport_remove_pending_events(struct gameport *gameport)
395 {
396         struct list_head *node, *next;
397         struct gameport_event *event;
398         unsigned long flags;
399
400         spin_lock_irqsave(&gameport_event_lock, flags);
401
402         list_for_each_safe(node, next, &gameport_event_list) {
403                 event = list_entry(node, struct gameport_event, node);
404                 if (event->object == gameport) {
405                         list_del_init(node);
406                         gameport_free_event(event);
407                 }
408         }
409
410         spin_unlock_irqrestore(&gameport_event_lock, flags);
411 }
412
413 /*
414  * Destroy child gameport port (if any) that has not been fully registered yet.
415  *
416  * Note that we rely on the fact that port can have only one child and therefore
417  * only one child registration request can be pending. Additionally, children
418  * are registered by driver's connect() handler so there can't be a grandchild
419  * pending registration together with a child.
420  */
421 static struct gameport *gameport_get_pending_child(struct gameport *parent)
422 {
423         struct gameport_event *event;
424         struct gameport *gameport, *child = NULL;
425         unsigned long flags;
426
427         spin_lock_irqsave(&gameport_event_lock, flags);
428
429         list_for_each_entry(event, &gameport_event_list, node) {
430                 if (event->type == GAMEPORT_REGISTER_PORT) {
431                         gameport = event->object;
432                         if (gameport->parent == parent) {
433                                 child = gameport;
434                                 break;
435                         }
436                 }
437         }
438
439         spin_unlock_irqrestore(&gameport_event_lock, flags);
440         return child;
441 }
442
443 static int gameport_thread(void *nothing)
444 {
445         do {
446                 gameport_handle_event();
447                 wait_event_interruptible(gameport_wait,
448                         kthread_should_stop() || !list_empty(&gameport_event_list));
449                 try_to_freeze();
450         } while (!kthread_should_stop());
451
452         printk(KERN_DEBUG "gameport: kgameportd exiting\n");
453         return 0;
454 }
455
456
457 /*
458  * Gameport port operations
459  */
460
461 static ssize_t gameport_show_description(struct device *dev, struct device_attribute *attr, char *buf)
462 {
463         struct gameport *gameport = to_gameport_port(dev);
464         return sprintf(buf, "%s\n", gameport->name);
465 }
466
467 static ssize_t gameport_rebind_driver(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
468 {
469         struct gameport *gameport = to_gameport_port(dev);
470         struct device_driver *drv;
471         int retval;
472
473         retval = mutex_lock_interruptible(&gameport_mutex);
474         if (retval)
475                 return retval;
476
477         retval = count;
478         if (!strncmp(buf, "none", count)) {
479                 gameport_disconnect_port(gameport);
480         } else if (!strncmp(buf, "reconnect", count)) {
481                 gameport_reconnect_port(gameport);
482         } else if (!strncmp(buf, "rescan", count)) {
483                 gameport_disconnect_port(gameport);
484                 gameport_find_driver(gameport);
485         } else if ((drv = driver_find(buf, &gameport_bus)) != NULL) {
486                 gameport_disconnect_port(gameport);
487                 gameport_bind_driver(gameport, to_gameport_driver(drv));
488                 put_driver(drv);
489         } else {
490                 retval = -EINVAL;
491         }
492
493         mutex_unlock(&gameport_mutex);
494
495         return retval;
496 }
497
498 static struct device_attribute gameport_device_attrs[] = {
499         __ATTR(description, S_IRUGO, gameport_show_description, NULL),
500         __ATTR(drvctl, S_IWUSR, NULL, gameport_rebind_driver),
501         __ATTR_NULL
502 };
503
504 static void gameport_release_port(struct device *dev)
505 {
506         struct gameport *gameport = to_gameport_port(dev);
507
508         kfree(gameport);
509         module_put(THIS_MODULE);
510 }
511
512 void gameport_set_phys(struct gameport *gameport, const char *fmt, ...)
513 {
514         va_list args;
515
516         va_start(args, fmt);
517         vsnprintf(gameport->phys, sizeof(gameport->phys), fmt, args);
518         va_end(args);
519 }
520
521 /*
522  * Prepare gameport port for registration.
523  */
524 static void gameport_init_port(struct gameport *gameport)
525 {
526         static atomic_t gameport_no = ATOMIC_INIT(0);
527
528         __module_get(THIS_MODULE);
529
530         mutex_init(&gameport->drv_mutex);
531         device_initialize(&gameport->dev);
532         snprintf(gameport->dev.bus_id, sizeof(gameport->dev.bus_id),
533                  "gameport%lu", (unsigned long)atomic_inc_return(&gameport_no) - 1);
534         gameport->dev.bus = &gameport_bus;
535         gameport->dev.release = gameport_release_port;
536         if (gameport->parent)
537                 gameport->dev.parent = &gameport->parent->dev;
538
539         INIT_LIST_HEAD(&gameport->node);
540         spin_lock_init(&gameport->timer_lock);
541         init_timer(&gameport->poll_timer);
542         gameport->poll_timer.function = gameport_run_poll_handler;
543         gameport->poll_timer.data = (unsigned long)gameport;
544 }
545
546 /*
547  * Complete gameport port registration.
548  * Driver core will attempt to find appropriate driver for the port.
549  */
550 static void gameport_add_port(struct gameport *gameport)
551 {
552         int error;
553
554         if (gameport->parent)
555                 gameport->parent->child = gameport;
556
557         gameport->speed = gameport_measure_speed(gameport);
558
559         list_add_tail(&gameport->node, &gameport_list);
560
561         if (gameport->io)
562                 printk(KERN_INFO "gameport: %s is %s, io %#x, speed %dkHz\n",
563                         gameport->name, gameport->phys, gameport->io, gameport->speed);
564         else
565                 printk(KERN_INFO "gameport: %s is %s, speed %dkHz\n",
566                         gameport->name, gameport->phys, gameport->speed);
567
568         error = device_add(&gameport->dev);
569         if (error)
570                 printk(KERN_ERR
571                         "gameport: device_add() failed for %s (%s), error: %d\n",
572                         gameport->phys, gameport->name, error);
573         else
574                 gameport->registered = 1;
575 }
576
577 /*
578  * gameport_destroy_port() completes deregistration process and removes
579  * port from the system
580  */
581 static void gameport_destroy_port(struct gameport *gameport)
582 {
583         struct gameport *child;
584
585         child = gameport_get_pending_child(gameport);
586         if (child) {
587                 gameport_remove_pending_events(child);
588                 put_device(&child->dev);
589         }
590
591         if (gameport->parent) {
592                 gameport->parent->child = NULL;
593                 gameport->parent = NULL;
594         }
595
596         if (gameport->registered) {
597                 device_del(&gameport->dev);
598                 gameport->registered = 0;
599         }
600
601         list_del_init(&gameport->node);
602
603         gameport_remove_pending_events(gameport);
604         put_device(&gameport->dev);
605 }
606
607 /*
608  * Reconnect gameport port and all its children (re-initialize attached devices)
609  */
610 static void gameport_reconnect_port(struct gameport *gameport)
611 {
612         do {
613                 if (!gameport->drv || !gameport->drv->reconnect || gameport->drv->reconnect(gameport)) {
614                         gameport_disconnect_port(gameport);
615                         gameport_find_driver(gameport);
616                         /* Ok, old children are now gone, we are done */
617                         break;
618                 }
619                 gameport = gameport->child;
620         } while (gameport);
621 }
622
623 /*
624  * gameport_disconnect_port() unbinds a port from its driver. As a side effect
625  * all child ports are unbound and destroyed.
626  */
627 static void gameport_disconnect_port(struct gameport *gameport)
628 {
629         struct gameport *s, *parent;
630
631         if (gameport->child) {
632                 /*
633                  * Children ports should be disconnected and destroyed
634                  * first, staring with the leaf one, since we don't want
635                  * to do recursion
636                  */
637                 for (s = gameport; s->child; s = s->child)
638                         /* empty */;
639
640                 do {
641                         parent = s->parent;
642
643                         gameport_release_driver(s);
644                         gameport_destroy_port(s);
645                 } while ((s = parent) != gameport);
646         }
647
648         /*
649          * Ok, no children left, now disconnect this port
650          */
651         gameport_release_driver(gameport);
652 }
653
654 void gameport_rescan(struct gameport *gameport)
655 {
656         gameport_queue_event(gameport, NULL, GAMEPORT_RESCAN);
657 }
658
659 void gameport_reconnect(struct gameport *gameport)
660 {
661         gameport_queue_event(gameport, NULL, GAMEPORT_RECONNECT);
662 }
663
664 /*
665  * Submits register request to kgameportd for subsequent execution.
666  * Note that port registration is always asynchronous.
667  */
668 void __gameport_register_port(struct gameport *gameport, struct module *owner)
669 {
670         gameport_init_port(gameport);
671         gameport_queue_event(gameport, owner, GAMEPORT_REGISTER_PORT);
672 }
673
674 /*
675  * Synchronously unregisters gameport port.
676  */
677 void gameport_unregister_port(struct gameport *gameport)
678 {
679         mutex_lock(&gameport_mutex);
680         gameport_disconnect_port(gameport);
681         gameport_destroy_port(gameport);
682         mutex_unlock(&gameport_mutex);
683 }
684
685
686 /*
687  * Gameport driver operations
688  */
689
690 static ssize_t gameport_driver_show_description(struct device_driver *drv, char *buf)
691 {
692         struct gameport_driver *driver = to_gameport_driver(drv);
693         return sprintf(buf, "%s\n", driver->description ? driver->description : "(none)");
694 }
695
696 static struct driver_attribute gameport_driver_attrs[] = {
697         __ATTR(description, S_IRUGO, gameport_driver_show_description, NULL),
698         __ATTR_NULL
699 };
700
701 static int gameport_driver_probe(struct device *dev)
702 {
703         struct gameport *gameport = to_gameport_port(dev);
704         struct gameport_driver *drv = to_gameport_driver(dev->driver);
705
706         drv->connect(gameport, drv);
707         return gameport->drv ? 0 : -ENODEV;
708 }
709
710 static int gameport_driver_remove(struct device *dev)
711 {
712         struct gameport *gameport = to_gameport_port(dev);
713         struct gameport_driver *drv = to_gameport_driver(dev->driver);
714
715         drv->disconnect(gameport);
716         return 0;
717 }
718
719 static struct bus_type gameport_bus = {
720         .name   = "gameport",
721         .probe  = gameport_driver_probe,
722         .remove = gameport_driver_remove,
723 };
724
725 static void gameport_add_driver(struct gameport_driver *drv)
726 {
727         int error;
728
729         error = driver_register(&drv->driver);
730         if (error)
731                 printk(KERN_ERR
732                         "gameport: driver_register() failed for %s, error: %d\n",
733                         drv->driver.name, error);
734 }
735
736 void __gameport_register_driver(struct gameport_driver *drv, struct module *owner)
737 {
738         drv->driver.bus = &gameport_bus;
739         gameport_queue_event(drv, owner, GAMEPORT_REGISTER_DRIVER);
740 }
741
742 void gameport_unregister_driver(struct gameport_driver *drv)
743 {
744         struct gameport *gameport;
745
746         mutex_lock(&gameport_mutex);
747         drv->ignore = 1;        /* so gameport_find_driver ignores it */
748
749 start_over:
750         list_for_each_entry(gameport, &gameport_list, node) {
751                 if (gameport->drv == drv) {
752                         gameport_disconnect_port(gameport);
753                         gameport_find_driver(gameport);
754                         /* we could've deleted some ports, restart */
755                         goto start_over;
756                 }
757         }
758
759         driver_unregister(&drv->driver);
760         mutex_unlock(&gameport_mutex);
761 }
762
763 static int gameport_bus_match(struct device *dev, struct device_driver *drv)
764 {
765         struct gameport_driver *gameport_drv = to_gameport_driver(drv);
766
767         return !gameport_drv->ignore;
768 }
769
770 static void gameport_set_drv(struct gameport *gameport, struct gameport_driver *drv)
771 {
772         mutex_lock(&gameport->drv_mutex);
773         gameport->drv = drv;
774         mutex_unlock(&gameport->drv_mutex);
775 }
776
777 int gameport_open(struct gameport *gameport, struct gameport_driver *drv, int mode)
778 {
779
780         if (gameport->open) {
781                 if (gameport->open(gameport, mode)) {
782                         return -1;
783                 }
784         } else {
785                 if (mode != GAMEPORT_MODE_RAW)
786                         return -1;
787         }
788
789         gameport_set_drv(gameport, drv);
790         return 0;
791 }
792
793 void gameport_close(struct gameport *gameport)
794 {
795         del_timer_sync(&gameport->poll_timer);
796         gameport->poll_handler = NULL;
797         gameport->poll_interval = 0;
798         gameport_set_drv(gameport, NULL);
799         if (gameport->close)
800                 gameport->close(gameport);
801 }
802
803 static int __init gameport_init(void)
804 {
805         int error;
806
807         gameport_bus.dev_attrs = gameport_device_attrs;
808         gameport_bus.drv_attrs = gameport_driver_attrs;
809         gameport_bus.match = gameport_bus_match;
810         error = bus_register(&gameport_bus);
811         if (error) {
812                 printk(KERN_ERR "gameport: failed to register gameport bus, error: %d\n", error);
813                 return error;
814         }
815
816         gameport_task = kthread_run(gameport_thread, NULL, "kgameportd");
817         if (IS_ERR(gameport_task)) {
818                 bus_unregister(&gameport_bus);
819                 error = PTR_ERR(gameport_task);
820                 printk(KERN_ERR "gameport: Failed to start kgameportd, error: %d\n", error);
821                 return error;
822         }
823
824         return 0;
825 }
826
827 static void __exit gameport_exit(void)
828 {
829         bus_unregister(&gameport_bus);
830         kthread_stop(gameport_task);
831 }
832
833 subsys_initcall(gameport_init);
834 module_exit(gameport_exit);