2 * The Serio abstraction module
4 * Copyright (c) 1999-2004 Vojtech Pavlik
5 * Copyright (c) 2004 Dmitry Torokhov
6 * Copyright (c) 2003 Daniele Bellucci
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.
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.
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
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
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>
40 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
41 MODULE_DESCRIPTION("Serio abstraction core");
42 MODULE_LICENSE("GPL");
44 EXPORT_SYMBOL(serio_interrupt);
45 EXPORT_SYMBOL(__serio_register_port);
46 EXPORT_SYMBOL(serio_unregister_port);
47 EXPORT_SYMBOL(serio_unregister_child_port);
48 EXPORT_SYMBOL(__serio_register_driver);
49 EXPORT_SYMBOL(serio_unregister_driver);
50 EXPORT_SYMBOL(serio_open);
51 EXPORT_SYMBOL(serio_close);
52 EXPORT_SYMBOL(serio_rescan);
53 EXPORT_SYMBOL(serio_reconnect);
56 * serio_mutex protects entire serio subsystem and is taken every time
57 * serio port or driver registrered or unregistered.
59 static DEFINE_MUTEX(serio_mutex);
61 static LIST_HEAD(serio_list);
63 static struct bus_type serio_bus;
65 static void serio_add_port(struct serio *serio);
66 static void serio_reconnect_port(struct serio *serio);
67 static void serio_disconnect_port(struct serio *serio);
68 static void serio_attach_driver(struct serio_driver *drv);
70 static int serio_connect_driver(struct serio *serio, struct serio_driver *drv)
74 mutex_lock(&serio->drv_mutex);
75 retval = drv->connect(serio, drv);
76 mutex_unlock(&serio->drv_mutex);
81 static int serio_reconnect_driver(struct serio *serio)
85 mutex_lock(&serio->drv_mutex);
86 if (serio->drv && serio->drv->reconnect)
87 retval = serio->drv->reconnect(serio);
88 mutex_unlock(&serio->drv_mutex);
93 static void serio_disconnect_driver(struct serio *serio)
95 mutex_lock(&serio->drv_mutex);
97 serio->drv->disconnect(serio);
98 mutex_unlock(&serio->drv_mutex);
101 static int serio_match_port(const struct serio_device_id *ids, struct serio *serio)
103 while (ids->type || ids->proto) {
104 if ((ids->type == SERIO_ANY || ids->type == serio->id.type) &&
105 (ids->proto == SERIO_ANY || ids->proto == serio->id.proto) &&
106 (ids->extra == SERIO_ANY || ids->extra == serio->id.extra) &&
107 (ids->id == SERIO_ANY || ids->id == serio->id.id))
115 * Basic serio -> driver core mappings
118 static int serio_bind_driver(struct serio *serio, struct serio_driver *drv)
122 if (serio_match_port(drv->id_table, serio)) {
124 serio->dev.driver = &drv->driver;
125 if (serio_connect_driver(serio, drv)) {
126 serio->dev.driver = NULL;
130 error = device_bind_driver(&serio->dev);
133 "serio: device_bind_driver() failed "
134 "for %s (%s) and %s, error: %d\n",
135 serio->phys, serio->name,
136 drv->description, error);
137 serio_disconnect_driver(serio);
138 serio->dev.driver = NULL;
145 static void serio_find_driver(struct serio *serio)
149 error = device_attach(&serio->dev);
152 "serio: device_attach() failed for %s (%s), error: %d\n",
153 serio->phys, serio->name, error);
158 * Serio event processing.
161 enum serio_event_type {
163 SERIO_RECONNECT_PORT,
169 enum serio_event_type type;
171 struct module *owner;
172 struct list_head node;
175 static DEFINE_SPINLOCK(serio_event_lock); /* protects serio_event_list */
176 static LIST_HEAD(serio_event_list);
177 static DECLARE_WAIT_QUEUE_HEAD(serio_wait);
178 static struct task_struct *serio_task;
180 static int serio_queue_event(void *object, struct module *owner,
181 enum serio_event_type event_type)
184 struct serio_event *event;
187 spin_lock_irqsave(&serio_event_lock, flags);
190 * Scan event list for the other events for the same serio port,
191 * starting with the most recent one. If event is the same we
192 * do not need add new one. If event is of different type we
193 * need to add this event and should not look further because
194 * we need to preseve sequence of distinct events.
196 list_for_each_entry_reverse(event, &serio_event_list, node) {
197 if (event->object == object) {
198 if (event->type == event_type)
204 event = kmalloc(sizeof(struct serio_event), GFP_ATOMIC);
207 "serio: Not enough memory to queue event %d\n",
213 if (!try_module_get(owner)) {
215 "serio: Can't get module reference, dropping event %d\n",
222 event->type = event_type;
223 event->object = object;
224 event->owner = owner;
226 list_add_tail(&event->node, &serio_event_list);
227 wake_up(&serio_wait);
230 spin_unlock_irqrestore(&serio_event_lock, flags);
234 static void serio_free_event(struct serio_event *event)
236 module_put(event->owner);
240 static void serio_remove_duplicate_events(struct serio_event *event)
242 struct list_head *node, *next;
243 struct serio_event *e;
246 spin_lock_irqsave(&serio_event_lock, flags);
248 list_for_each_safe(node, next, &serio_event_list) {
249 e = list_entry(node, struct serio_event, node);
250 if (event->object == e->object) {
252 * If this event is of different type we should not
253 * look further - we only suppress duplicate events
254 * that were sent back-to-back.
256 if (event->type != e->type)
264 spin_unlock_irqrestore(&serio_event_lock, flags);
268 static struct serio_event *serio_get_event(void)
270 struct serio_event *event;
271 struct list_head *node;
274 spin_lock_irqsave(&serio_event_lock, flags);
276 if (list_empty(&serio_event_list)) {
277 spin_unlock_irqrestore(&serio_event_lock, flags);
281 node = serio_event_list.next;
282 event = list_entry(node, struct serio_event, node);
285 spin_unlock_irqrestore(&serio_event_lock, flags);
290 static void serio_handle_event(void)
292 struct serio_event *event;
294 mutex_lock(&serio_mutex);
297 * Note that we handle only one event here to give swsusp
298 * a chance to freeze kseriod thread. Serio events should
299 * be pretty rare so we are not concerned about taking
302 if ((event = serio_get_event())) {
304 switch (event->type) {
305 case SERIO_REGISTER_PORT:
306 serio_add_port(event->object);
309 case SERIO_RECONNECT_PORT:
310 serio_reconnect_port(event->object);
313 case SERIO_RESCAN_PORT:
314 serio_disconnect_port(event->object);
315 serio_find_driver(event->object);
318 case SERIO_ATTACH_DRIVER:
319 serio_attach_driver(event->object);
326 serio_remove_duplicate_events(event);
327 serio_free_event(event);
330 mutex_unlock(&serio_mutex);
334 * Remove all events that have been submitted for a given serio port.
336 static void serio_remove_pending_events(struct serio *serio)
338 struct list_head *node, *next;
339 struct serio_event *event;
342 spin_lock_irqsave(&serio_event_lock, flags);
344 list_for_each_safe(node, next, &serio_event_list) {
345 event = list_entry(node, struct serio_event, node);
346 if (event->object == serio) {
348 serio_free_event(event);
352 spin_unlock_irqrestore(&serio_event_lock, flags);
356 * Destroy child serio port (if any) that has not been fully registered yet.
358 * Note that we rely on the fact that port can have only one child and therefore
359 * only one child registration request can be pending. Additionally, children
360 * are registered by driver's connect() handler so there can't be a grandchild
361 * pending registration together with a child.
363 static struct serio *serio_get_pending_child(struct serio *parent)
365 struct serio_event *event;
366 struct serio *serio, *child = NULL;
369 spin_lock_irqsave(&serio_event_lock, flags);
371 list_for_each_entry(event, &serio_event_list, node) {
372 if (event->type == SERIO_REGISTER_PORT) {
373 serio = event->object;
374 if (serio->parent == parent) {
381 spin_unlock_irqrestore(&serio_event_lock, flags);
385 static int serio_thread(void *nothing)
389 serio_handle_event();
390 wait_event_freezable(serio_wait,
391 kthread_should_stop() || !list_empty(&serio_event_list));
392 } while (!kthread_should_stop());
394 printk(KERN_DEBUG "serio: kseriod exiting\n");
400 * Serio port operations
403 static ssize_t serio_show_description(struct device *dev, struct device_attribute *attr, char *buf)
405 struct serio *serio = to_serio_port(dev);
406 return sprintf(buf, "%s\n", serio->name);
409 static ssize_t serio_show_modalias(struct device *dev, struct device_attribute *attr, char *buf)
411 struct serio *serio = to_serio_port(dev);
413 return sprintf(buf, "serio:ty%02Xpr%02Xid%02Xex%02X\n",
414 serio->id.type, serio->id.proto, serio->id.id, serio->id.extra);
417 static ssize_t serio_show_id_type(struct device *dev, struct device_attribute *attr, char *buf)
419 struct serio *serio = to_serio_port(dev);
420 return sprintf(buf, "%02x\n", serio->id.type);
423 static ssize_t serio_show_id_proto(struct device *dev, struct device_attribute *attr, char *buf)
425 struct serio *serio = to_serio_port(dev);
426 return sprintf(buf, "%02x\n", serio->id.proto);
429 static ssize_t serio_show_id_id(struct device *dev, struct device_attribute *attr, char *buf)
431 struct serio *serio = to_serio_port(dev);
432 return sprintf(buf, "%02x\n", serio->id.id);
435 static ssize_t serio_show_id_extra(struct device *dev, struct device_attribute *attr, char *buf)
437 struct serio *serio = to_serio_port(dev);
438 return sprintf(buf, "%02x\n", serio->id.extra);
441 static DEVICE_ATTR(type, S_IRUGO, serio_show_id_type, NULL);
442 static DEVICE_ATTR(proto, S_IRUGO, serio_show_id_proto, NULL);
443 static DEVICE_ATTR(id, S_IRUGO, serio_show_id_id, NULL);
444 static DEVICE_ATTR(extra, S_IRUGO, serio_show_id_extra, NULL);
446 static struct attribute *serio_device_id_attrs[] = {
448 &dev_attr_proto.attr,
450 &dev_attr_extra.attr,
454 static struct attribute_group serio_id_attr_group = {
456 .attrs = serio_device_id_attrs,
459 static ssize_t serio_rebind_driver(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
461 struct serio *serio = to_serio_port(dev);
462 struct device_driver *drv;
465 error = mutex_lock_interruptible(&serio_mutex);
469 if (!strncmp(buf, "none", count)) {
470 serio_disconnect_port(serio);
471 } else if (!strncmp(buf, "reconnect", count)) {
472 serio_reconnect_port(serio);
473 } else if (!strncmp(buf, "rescan", count)) {
474 serio_disconnect_port(serio);
475 serio_find_driver(serio);
476 } else if ((drv = driver_find(buf, &serio_bus)) != NULL) {
477 serio_disconnect_port(serio);
478 error = serio_bind_driver(serio, to_serio_driver(drv));
484 mutex_unlock(&serio_mutex);
486 return error ? error : count;
489 static ssize_t serio_show_bind_mode(struct device *dev, struct device_attribute *attr, char *buf)
491 struct serio *serio = to_serio_port(dev);
492 return sprintf(buf, "%s\n", serio->manual_bind ? "manual" : "auto");
495 static ssize_t serio_set_bind_mode(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
497 struct serio *serio = to_serio_port(dev);
501 if (!strncmp(buf, "manual", count)) {
502 serio->manual_bind = 1;
503 } else if (!strncmp(buf, "auto", count)) {
504 serio->manual_bind = 0;
512 static struct device_attribute serio_device_attrs[] = {
513 __ATTR(description, S_IRUGO, serio_show_description, NULL),
514 __ATTR(modalias, S_IRUGO, serio_show_modalias, NULL),
515 __ATTR(drvctl, S_IWUSR, NULL, serio_rebind_driver),
516 __ATTR(bind_mode, S_IWUSR | S_IRUGO, serio_show_bind_mode, serio_set_bind_mode),
521 static void serio_release_port(struct device *dev)
523 struct serio *serio = to_serio_port(dev);
526 module_put(THIS_MODULE);
530 * Prepare serio port for registration.
532 static void serio_init_port(struct serio *serio)
534 static atomic_t serio_no = ATOMIC_INIT(0);
536 __module_get(THIS_MODULE);
538 INIT_LIST_HEAD(&serio->node);
539 spin_lock_init(&serio->lock);
540 mutex_init(&serio->drv_mutex);
541 device_initialize(&serio->dev);
542 snprintf(serio->dev.bus_id, sizeof(serio->dev.bus_id),
543 "serio%ld", (long)atomic_inc_return(&serio_no) - 1);
544 serio->dev.bus = &serio_bus;
545 serio->dev.release = serio_release_port;
547 serio->dev.parent = &serio->parent->dev;
548 serio->depth = serio->parent->depth + 1;
551 lockdep_set_subclass(&serio->lock, serio->depth);
555 * Complete serio port registration.
556 * Driver core will attempt to find appropriate driver for the port.
558 static void serio_add_port(struct serio *serio)
563 serio_pause_rx(serio->parent);
564 serio->parent->child = serio;
565 serio_continue_rx(serio->parent);
568 list_add_tail(&serio->node, &serio_list);
571 error = device_add(&serio->dev);
574 "serio: device_add() failed for %s (%s), error: %d\n",
575 serio->phys, serio->name, error);
577 serio->registered = 1;
578 error = sysfs_create_group(&serio->dev.kobj, &serio_id_attr_group);
581 "serio: sysfs_create_group() failed for %s (%s), error: %d\n",
582 serio->phys, serio->name, error);
587 * serio_destroy_port() completes deregistration process and removes
588 * port from the system
590 static void serio_destroy_port(struct serio *serio)
594 child = serio_get_pending_child(serio);
596 serio_remove_pending_events(child);
597 put_device(&child->dev);
604 serio_pause_rx(serio->parent);
605 serio->parent->child = NULL;
606 serio_continue_rx(serio->parent);
607 serio->parent = NULL;
610 if (serio->registered) {
611 sysfs_remove_group(&serio->dev.kobj, &serio_id_attr_group);
612 device_del(&serio->dev);
613 serio->registered = 0;
616 list_del_init(&serio->node);
617 serio_remove_pending_events(serio);
618 put_device(&serio->dev);
622 * Reconnect serio port and all its children (re-initialize attached devices)
624 static void serio_reconnect_port(struct serio *serio)
627 if (serio_reconnect_driver(serio)) {
628 serio_disconnect_port(serio);
629 serio_find_driver(serio);
630 /* Ok, old children are now gone, we are done */
633 serio = serio->child;
638 * serio_disconnect_port() unbinds a port from its driver. As a side effect
639 * all child ports are unbound and destroyed.
641 static void serio_disconnect_port(struct serio *serio)
643 struct serio *s, *parent;
647 * Children ports should be disconnected and destroyed
648 * first, staring with the leaf one, since we don't want
651 for (s = serio; s->child; s = s->child)
657 device_release_driver(&s->dev);
658 serio_destroy_port(s);
659 } while ((s = parent) != serio);
663 * Ok, no children left, now disconnect this port
665 device_release_driver(&serio->dev);
668 void serio_rescan(struct serio *serio)
670 serio_queue_event(serio, NULL, SERIO_RESCAN_PORT);
673 void serio_reconnect(struct serio *serio)
675 serio_queue_event(serio, NULL, SERIO_RECONNECT_PORT);
679 * Submits register request to kseriod for subsequent execution.
680 * Note that port registration is always asynchronous.
682 void __serio_register_port(struct serio *serio, struct module *owner)
684 serio_init_port(serio);
685 serio_queue_event(serio, owner, SERIO_REGISTER_PORT);
689 * Synchronously unregisters serio port.
691 void serio_unregister_port(struct serio *serio)
693 mutex_lock(&serio_mutex);
694 serio_disconnect_port(serio);
695 serio_destroy_port(serio);
696 mutex_unlock(&serio_mutex);
700 * Safely unregisters child port if one is present.
702 void serio_unregister_child_port(struct serio *serio)
704 mutex_lock(&serio_mutex);
706 serio_disconnect_port(serio->child);
707 serio_destroy_port(serio->child);
709 mutex_unlock(&serio_mutex);
714 * Serio driver operations
717 static ssize_t serio_driver_show_description(struct device_driver *drv, char *buf)
719 struct serio_driver *driver = to_serio_driver(drv);
720 return sprintf(buf, "%s\n", driver->description ? driver->description : "(none)");
723 static ssize_t serio_driver_show_bind_mode(struct device_driver *drv, char *buf)
725 struct serio_driver *serio_drv = to_serio_driver(drv);
726 return sprintf(buf, "%s\n", serio_drv->manual_bind ? "manual" : "auto");
729 static ssize_t serio_driver_set_bind_mode(struct device_driver *drv, const char *buf, size_t count)
731 struct serio_driver *serio_drv = to_serio_driver(drv);
735 if (!strncmp(buf, "manual", count)) {
736 serio_drv->manual_bind = 1;
737 } else if (!strncmp(buf, "auto", count)) {
738 serio_drv->manual_bind = 0;
747 static struct driver_attribute serio_driver_attrs[] = {
748 __ATTR(description, S_IRUGO, serio_driver_show_description, NULL),
749 __ATTR(bind_mode, S_IWUSR | S_IRUGO,
750 serio_driver_show_bind_mode, serio_driver_set_bind_mode),
754 static int serio_driver_probe(struct device *dev)
756 struct serio *serio = to_serio_port(dev);
757 struct serio_driver *drv = to_serio_driver(dev->driver);
759 return serio_connect_driver(serio, drv);
762 static int serio_driver_remove(struct device *dev)
764 struct serio *serio = to_serio_port(dev);
766 serio_disconnect_driver(serio);
770 static void serio_cleanup(struct serio *serio)
772 mutex_lock(&serio->drv_mutex);
773 if (serio->drv && serio->drv->cleanup)
774 serio->drv->cleanup(serio);
775 mutex_unlock(&serio->drv_mutex);
778 static void serio_shutdown(struct device *dev)
780 struct serio *serio = to_serio_port(dev);
782 serio_cleanup(serio);
785 static void serio_attach_driver(struct serio_driver *drv)
789 error = driver_attach(&drv->driver);
792 "serio: driver_attach() failed for %s with error %d\n",
793 drv->driver.name, error);
796 int __serio_register_driver(struct serio_driver *drv, struct module *owner, const char *mod_name)
798 int manual_bind = drv->manual_bind;
801 drv->driver.bus = &serio_bus;
802 drv->driver.owner = owner;
803 drv->driver.mod_name = mod_name;
806 * Temporarily disable automatic binding because probing
807 * takes long time and we are better off doing it in kseriod
809 drv->manual_bind = 1;
811 error = driver_register(&drv->driver);
814 "serio: driver_register() failed for %s, error: %d\n",
815 drv->driver.name, error);
820 * Restore original bind mode and let kseriod bind the
821 * driver to free ports
824 drv->manual_bind = 0;
825 error = serio_queue_event(drv, NULL, SERIO_ATTACH_DRIVER);
827 driver_unregister(&drv->driver);
835 void serio_unregister_driver(struct serio_driver *drv)
839 mutex_lock(&serio_mutex);
840 drv->manual_bind = 1; /* so serio_find_driver ignores it */
843 list_for_each_entry(serio, &serio_list, node) {
844 if (serio->drv == drv) {
845 serio_disconnect_port(serio);
846 serio_find_driver(serio);
847 /* we could've deleted some ports, restart */
852 driver_unregister(&drv->driver);
853 mutex_unlock(&serio_mutex);
856 static void serio_set_drv(struct serio *serio, struct serio_driver *drv)
858 serio_pause_rx(serio);
860 serio_continue_rx(serio);
863 static int serio_bus_match(struct device *dev, struct device_driver *drv)
865 struct serio *serio = to_serio_port(dev);
866 struct serio_driver *serio_drv = to_serio_driver(drv);
868 if (serio->manual_bind || serio_drv->manual_bind)
871 return serio_match_port(serio_drv->id_table, serio);
874 #ifdef CONFIG_HOTPLUG
876 #define SERIO_ADD_UEVENT_VAR(fmt, val...) \
878 int err = add_uevent_var(env, fmt, val); \
883 static int serio_uevent(struct device *dev, struct kobj_uevent_env *env)
890 serio = to_serio_port(dev);
892 SERIO_ADD_UEVENT_VAR("SERIO_TYPE=%02x", serio->id.type);
893 SERIO_ADD_UEVENT_VAR("SERIO_PROTO=%02x", serio->id.proto);
894 SERIO_ADD_UEVENT_VAR("SERIO_ID=%02x", serio->id.id);
895 SERIO_ADD_UEVENT_VAR("SERIO_EXTRA=%02x", serio->id.extra);
896 SERIO_ADD_UEVENT_VAR("MODALIAS=serio:ty%02Xpr%02Xid%02Xex%02X",
897 serio->id.type, serio->id.proto, serio->id.id, serio->id.extra);
901 #undef SERIO_ADD_UEVENT_VAR
905 static int serio_uevent(struct device *dev, struct kobj_uevent_env *env)
910 #endif /* CONFIG_HOTPLUG */
913 static int serio_suspend(struct device *dev, pm_message_t state)
915 if (dev->power.power_state.event != state.event) {
916 if (state.event == PM_EVENT_SUSPEND)
917 serio_cleanup(to_serio_port(dev));
919 dev->power.power_state = state;
925 static int serio_resume(struct device *dev)
927 struct serio *serio = to_serio_port(dev);
929 if (dev->power.power_state.event != PM_EVENT_ON &&
930 serio_reconnect_driver(serio)) {
932 * Driver re-probing can take a while, so better let kseriod
938 dev->power.power_state = PMSG_ON;
942 #endif /* CONFIG_PM */
944 /* called from serio_driver->connect/disconnect methods under serio_mutex */
945 int serio_open(struct serio *serio, struct serio_driver *drv)
947 serio_set_drv(serio, drv);
949 if (serio->open && serio->open(serio)) {
950 serio_set_drv(serio, NULL);
956 /* called from serio_driver->connect/disconnect methods under serio_mutex */
957 void serio_close(struct serio *serio)
962 serio_set_drv(serio, NULL);
965 irqreturn_t serio_interrupt(struct serio *serio,
966 unsigned char data, unsigned int dfl)
969 irqreturn_t ret = IRQ_NONE;
971 spin_lock_irqsave(&serio->lock, flags);
973 if (likely(serio->drv)) {
974 ret = serio->drv->interrupt(serio, data, dfl);
975 } else if (!dfl && serio->registered) {
980 spin_unlock_irqrestore(&serio->lock, flags);
985 static struct bus_type serio_bus = {
987 .dev_attrs = serio_device_attrs,
988 .drv_attrs = serio_driver_attrs,
989 .match = serio_bus_match,
990 .uevent = serio_uevent,
991 .probe = serio_driver_probe,
992 .remove = serio_driver_remove,
993 .shutdown = serio_shutdown,
995 .suspend = serio_suspend,
996 .resume = serio_resume,
1000 static int __init serio_init(void)
1004 error = bus_register(&serio_bus);
1006 printk(KERN_ERR "serio: failed to register serio bus, error: %d\n", error);
1010 serio_task = kthread_run(serio_thread, NULL, "kseriod");
1011 if (IS_ERR(serio_task)) {
1012 bus_unregister(&serio_bus);
1013 error = PTR_ERR(serio_task);
1014 printk(KERN_ERR "serio: Failed to start kseriod, error: %d\n", error);
1021 static void __exit serio_exit(void)
1023 bus_unregister(&serio_bus);
1024 kthread_stop(serio_task);
1027 subsys_initcall(serio_init);
1028 module_exit(serio_exit);