X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=drivers%2Finput%2Fserio%2Fserio.c;h=f0ce822c1028741efabecf0cef37e1e356754eb5;hb=97bf2856c6014879bd04983a3e9dfcdac1e7fe85;hp=6f003197b62c3a6460bd320f6ddb68894972ec26;hpb=9213980e6a70d8473e0ffd4b39ab5b6caaba9ff5;p=linux-2.6.git

diff --git a/drivers/input/serio/serio.c b/drivers/input/serio/serio.c
index 6f003197b..f0ce822c1 100644
--- a/drivers/input/serio/serio.c
+++ b/drivers/input/serio/serio.c
@@ -1,11 +1,9 @@
-/*
- * $Id: serio.c,v 1.15 2002/01/22 21:12:03 vojtech Exp $
- *
- *  Copyright (c) 1999-2001 Vojtech Pavlik
- */
-
 /*
  *  The Serio abstraction module
+ *
+ *  Copyright (c) 1999-2004 Vojtech Pavlik
+ *  Copyright (c) 2004 Dmitry Torokhov
+ *  Copyright (c) 2003 Daniele Bellucci
  */
 
 /*
@@ -26,10 +24,6 @@
  * Should you need to contact me, the author, you can do so either by
  * e-mail - mail your message to <vojtech@ucw.cz>, or by paper mail:
  * Vojtech Pavlik, Simunkova 1594, Prague 8, 182 00 Czech Republic
- *
- * Changes:
- * 20 Jul. 2003    Daniele Bellucci <bellucda@tiscali.it>
- *                 Minor cleanups.
  */
 
 #include <linux/stddef.h>
@@ -37,298 +31,976 @@
 #include <linux/serio.h>
 #include <linux/errno.h>
 #include <linux/wait.h>
-#include <linux/completion.h>
 #include <linux/sched.h>
-#include <linux/smp_lock.h>
-#include <linux/suspend.h>
 #include <linux/slab.h>
+#include <linux/kthread.h>
+#include <linux/mutex.h>
+#include <linux/freezer.h>
 
 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
 MODULE_DESCRIPTION("Serio abstraction core");
 MODULE_LICENSE("GPL");
 
 EXPORT_SYMBOL(serio_interrupt);
-EXPORT_SYMBOL(serio_register_port);
-EXPORT_SYMBOL(serio_register_port_delayed);
 EXPORT_SYMBOL(__serio_register_port);
 EXPORT_SYMBOL(serio_unregister_port);
-EXPORT_SYMBOL(serio_unregister_port_delayed);
-EXPORT_SYMBOL(__serio_unregister_port);
-EXPORT_SYMBOL(serio_register_device);
-EXPORT_SYMBOL(serio_unregister_device);
+EXPORT_SYMBOL(serio_unregister_child_port);
+EXPORT_SYMBOL(serio_register_driver);
+EXPORT_SYMBOL(serio_unregister_driver);
 EXPORT_SYMBOL(serio_open);
 EXPORT_SYMBOL(serio_close);
 EXPORT_SYMBOL(serio_rescan);
 EXPORT_SYMBOL(serio_reconnect);
 
+/*
+ * serio_mutex protects entire serio subsystem and is taken every time
+ * serio port or driver registrered or unregistered.
+ */
+static DEFINE_MUTEX(serio_mutex);
+
+static LIST_HEAD(serio_list);
+
+static struct bus_type serio_bus;
+
+static void serio_add_port(struct serio *serio);
+static void serio_reconnect_port(struct serio *serio);
+static void serio_disconnect_port(struct serio *serio);
+static void serio_attach_driver(struct serio_driver *drv);
+
+static int serio_connect_driver(struct serio *serio, struct serio_driver *drv)
+{
+	int retval;
+
+	mutex_lock(&serio->drv_mutex);
+	retval = drv->connect(serio, drv);
+	mutex_unlock(&serio->drv_mutex);
+
+	return retval;
+}
+
+static int serio_reconnect_driver(struct serio *serio)
+{
+	int retval = -1;
+
+	mutex_lock(&serio->drv_mutex);
+	if (serio->drv && serio->drv->reconnect)
+		retval = serio->drv->reconnect(serio);
+	mutex_unlock(&serio->drv_mutex);
+
+	return retval;
+}
+
+static void serio_disconnect_driver(struct serio *serio)
+{
+	mutex_lock(&serio->drv_mutex);
+	if (serio->drv)
+		serio->drv->disconnect(serio);
+	mutex_unlock(&serio->drv_mutex);
+}
+
+static int serio_match_port(const struct serio_device_id *ids, struct serio *serio)
+{
+	while (ids->type || ids->proto) {
+		if ((ids->type == SERIO_ANY || ids->type == serio->id.type) &&
+		    (ids->proto == SERIO_ANY || ids->proto == serio->id.proto) &&
+		    (ids->extra == SERIO_ANY || ids->extra == serio->id.extra) &&
+		    (ids->id == SERIO_ANY || ids->id == serio->id.id))
+			return 1;
+		ids++;
+	}
+	return 0;
+}
+
+/*
+ * Basic serio -> driver core mappings
+ */
+
+static void serio_bind_driver(struct serio *serio, struct serio_driver *drv)
+{
+	int error;
+
+	down_write(&serio_bus.subsys.rwsem);
+
+	if (serio_match_port(drv->id_table, serio)) {
+		serio->dev.driver = &drv->driver;
+		if (serio_connect_driver(serio, drv)) {
+			serio->dev.driver = NULL;
+			goto out;
+		}
+		error = device_bind_driver(&serio->dev);
+		if (error) {
+			printk(KERN_WARNING
+				"serio: device_bind_driver() failed "
+				"for %s (%s) and %s, error: %d\n",
+				serio->phys, serio->name,
+				drv->description, error);
+			serio_disconnect_driver(serio);
+			serio->dev.driver = NULL;
+			goto out;
+		}
+	}
+ out:
+	up_write(&serio_bus.subsys.rwsem);
+}
+
+static void serio_release_driver(struct serio *serio)
+{
+	down_write(&serio_bus.subsys.rwsem);
+	device_release_driver(&serio->dev);
+	up_write(&serio_bus.subsys.rwsem);
+}
+
+static void serio_find_driver(struct serio *serio)
+{
+	int error;
+
+	down_write(&serio_bus.subsys.rwsem);
+	error = device_attach(&serio->dev);
+	if (error < 0)
+		printk(KERN_WARNING
+			"serio: device_attach() failed for %s (%s), error: %d\n",
+			serio->phys, serio->name, error);
+	up_write(&serio_bus.subsys.rwsem);
+}
+
+
+/*
+ * Serio event processing.
+ */
+
+enum serio_event_type {
+	SERIO_RESCAN_PORT,
+	SERIO_RECONNECT_PORT,
+	SERIO_REGISTER_PORT,
+	SERIO_ATTACH_DRIVER,
+};
+
 struct serio_event {
-	int type;
-	struct serio *serio;
+	enum serio_event_type type;
+	void *object;
+	struct module *owner;
 	struct list_head node;
 };
 
-static DECLARE_MUTEX(serio_sem);
-static LIST_HEAD(serio_list);
-static LIST_HEAD(serio_dev_list);
+static DEFINE_SPINLOCK(serio_event_lock);	/* protects serio_event_list */
 static LIST_HEAD(serio_event_list);
-static int serio_pid;
+static DECLARE_WAIT_QUEUE_HEAD(serio_wait);
+static struct task_struct *serio_task;
 
-static void serio_find_dev(struct serio *serio)
+static int serio_queue_event(void *object, struct module *owner,
+			     enum serio_event_type event_type)
 {
-	struct serio_dev *dev;
-
-	list_for_each_entry(dev, &serio_dev_list, node) {
-		if (serio->dev)
+	unsigned long flags;
+	struct serio_event *event;
+	int retval = 0;
+
+	spin_lock_irqsave(&serio_event_lock, flags);
+
+	/*
+	 * Scan event list for the other events for the same serio port,
+	 * starting with the most recent one. If event is the same we
+	 * do not need add new one. If event is of different type we
+	 * need to add this event and should not look further because
+	 * we need to preseve sequence of distinct events.
+	 */
+	list_for_each_entry_reverse(event, &serio_event_list, node) {
+		if (event->object == object) {
+			if (event->type == event_type)
+				goto out;
 			break;
-		if (dev->connect)
-			dev->connect(serio, dev);
+		}
+	}
+
+	event = kmalloc(sizeof(struct serio_event), GFP_ATOMIC);
+	if (!event) {
+		printk(KERN_ERR
+			"serio: Not enough memory to queue event %d\n",
+			event_type);
+		retval = -ENOMEM;
+		goto out;
+	}
+
+	if (!try_module_get(owner)) {
+		printk(KERN_WARNING
+			"serio: Can't get module reference, dropping event %d\n",
+			event_type);
+		kfree(event);
+		retval = -EINVAL;
+		goto out;
 	}
+
+	event->type = event_type;
+	event->object = object;
+	event->owner = owner;
+
+	list_add_tail(&event->node, &serio_event_list);
+	wake_up(&serio_wait);
+
+out:
+	spin_unlock_irqrestore(&serio_event_lock, flags);
+	return retval;
 }
 
-#define SERIO_RESCAN		1
-#define SERIO_RECONNECT		2
-#define SERIO_REGISTER_PORT	3
-#define SERIO_UNREGISTER_PORT	4
+static void serio_free_event(struct serio_event *event)
+{
+	module_put(event->owner);
+	kfree(event);
+}
 
-static DECLARE_WAIT_QUEUE_HEAD(serio_wait);
-static DECLARE_COMPLETION(serio_exited);
+static void serio_remove_duplicate_events(struct serio_event *event)
+{
+	struct list_head *node, *next;
+	struct serio_event *e;
+	unsigned long flags;
+
+	spin_lock_irqsave(&serio_event_lock, flags);
 
-static void serio_invalidate_pending_events(struct serio *serio)
+	list_for_each_safe(node, next, &serio_event_list) {
+		e = list_entry(node, struct serio_event, node);
+		if (event->object == e->object) {
+			/*
+			 * If this event is of different type we should not
+			 * look further - we only suppress duplicate events
+			 * that were sent back-to-back.
+			 */
+			if (event->type != e->type)
+				break;
+
+			list_del_init(node);
+			serio_free_event(e);
+		}
+	}
+
+	spin_unlock_irqrestore(&serio_event_lock, flags);
+}
+
+
+static struct serio_event *serio_get_event(void)
 {
 	struct serio_event *event;
+	struct list_head *node;
+	unsigned long flags;
+
+	spin_lock_irqsave(&serio_event_lock, flags);
 
-	list_for_each_entry(event, &serio_event_list, node)
-		if (event->serio == serio)
-			event->serio = NULL;
+	if (list_empty(&serio_event_list)) {
+		spin_unlock_irqrestore(&serio_event_lock, flags);
+		return NULL;
+	}
+
+	node = serio_event_list.next;
+	event = list_entry(node, struct serio_event, node);
+	list_del_init(node);
+
+	spin_unlock_irqrestore(&serio_event_lock, flags);
+
+	return event;
 }
 
-void serio_handle_events(void)
+static void serio_handle_event(void)
 {
-	struct list_head *node, *next;
 	struct serio_event *event;
 
-	list_for_each_safe(node, next, &serio_event_list) {
-		event = container_of(node, struct serio_event, node);
+	mutex_lock(&serio_mutex);
 
-		down(&serio_sem);
-		if (event->serio == NULL)
-			goto event_done;
+	/*
+	 * Note that we handle only one event here to give swsusp
+	 * a chance to freeze kseriod thread. Serio events should
+	 * be pretty rare so we are not concerned about taking
+	 * performance hit.
+	 */
+	if ((event = serio_get_event())) {
 
 		switch (event->type) {
-			case SERIO_REGISTER_PORT :
-				__serio_register_port(event->serio);
+			case SERIO_REGISTER_PORT:
+				serio_add_port(event->object);
 				break;
 
-			case SERIO_UNREGISTER_PORT :
-				__serio_unregister_port(event->serio);
+			case SERIO_RECONNECT_PORT:
+				serio_reconnect_port(event->object);
 				break;
 
-			case SERIO_RECONNECT :
-				if (event->serio->dev && event->serio->dev->reconnect)
-					if (event->serio->dev->reconnect(event->serio) == 0)
-						break;
-				/* reconnect failed - fall through to rescan */
+			case SERIO_RESCAN_PORT:
+				serio_disconnect_port(event->object);
+				serio_find_driver(event->object);
+				break;
 
-			case SERIO_RESCAN :
-				if (event->serio->dev && event->serio->dev->disconnect)
-					event->serio->dev->disconnect(event->serio);
-				serio_find_dev(event->serio);
+			case SERIO_ATTACH_DRIVER:
+				serio_attach_driver(event->object);
 				break;
+
 			default:
 				break;
 		}
-event_done:
-		up(&serio_sem);
-		list_del_init(node);
-		kfree(event);
+
+		serio_remove_duplicate_events(event);
+		serio_free_event(event);
 	}
+
+	mutex_unlock(&serio_mutex);
 }
 
-static int serio_thread(void *nothing)
+/*
+ * Remove all events that have been submitted for a given serio port.
+ */
+static void serio_remove_pending_events(struct serio *serio)
 {
-	lock_kernel();
-	daemonize("kseriod");
-	allow_signal(SIGTERM);
+	struct list_head *node, *next;
+	struct serio_event *event;
+	unsigned long flags;
 
-	do {
-		serio_handle_events();
-		wait_event_interruptible(serio_wait, !list_empty(&serio_event_list));
-		if (current->flags & PF_FREEZE)
-			refrigerator(PF_FREEZE);
-	} while (!signal_pending(current));
+	spin_lock_irqsave(&serio_event_lock, flags);
 
-	printk(KERN_DEBUG "serio: kseriod exiting\n");
+	list_for_each_safe(node, next, &serio_event_list) {
+		event = list_entry(node, struct serio_event, node);
+		if (event->object == serio) {
+			list_del_init(node);
+			serio_free_event(event);
+		}
+	}
 
-	unlock_kernel();
-	complete_and_exit(&serio_exited, 0);
+	spin_unlock_irqrestore(&serio_event_lock, flags);
 }
 
-static void serio_queue_event(struct serio *serio, int event_type)
+/*
+ * Destroy child serio port (if any) that has not been fully registered yet.
+ *
+ * Note that we rely on the fact that port can have only one child and therefore
+ * only one child registration request can be pending. Additionally, children
+ * are registered by driver's connect() handler so there can't be a grandchild
+ * pending registration together with a child.
+ */
+static struct serio *serio_get_pending_child(struct serio *parent)
 {
 	struct serio_event *event;
+	struct serio *serio, *child = NULL;
+	unsigned long flags;
 
-	if ((event = kmalloc(sizeof(struct serio_event), GFP_ATOMIC))) {
-		event->type = event_type;
-		event->serio = serio;
+	spin_lock_irqsave(&serio_event_lock, flags);
 
-		list_add_tail(&event->node, &serio_event_list);
-		wake_up(&serio_wait);
+	list_for_each_entry(event, &serio_event_list, node) {
+		if (event->type == SERIO_REGISTER_PORT) {
+			serio = event->object;
+			if (serio->parent == parent) {
+				child = serio;
+				break;
+			}
+		}
 	}
+
+	spin_unlock_irqrestore(&serio_event_lock, flags);
+	return child;
 }
 
-void serio_rescan(struct serio *serio)
+static int serio_thread(void *nothing)
 {
-	serio_queue_event(serio, SERIO_RESCAN);
+	do {
+		serio_handle_event();
+		wait_event_interruptible(serio_wait,
+			kthread_should_stop() || !list_empty(&serio_event_list));
+		try_to_freeze();
+	} while (!kthread_should_stop());
+
+	printk(KERN_DEBUG "serio: kseriod exiting\n");
+	return 0;
 }
 
-void serio_reconnect(struct serio *serio)
+
+/*
+ * Serio port operations
+ */
+
+static ssize_t serio_show_description(struct device *dev, struct device_attribute *attr, char *buf)
 {
-	serio_queue_event(serio, SERIO_RECONNECT);
+	struct serio *serio = to_serio_port(dev);
+	return sprintf(buf, "%s\n", serio->name);
 }
 
-irqreturn_t serio_interrupt(struct serio *serio,
-		unsigned char data, unsigned int flags, struct pt_regs *regs)
+static ssize_t serio_show_modalias(struct device *dev, struct device_attribute *attr, char *buf)
 {
-	irqreturn_t ret = IRQ_NONE;
+	struct serio *serio = to_serio_port(dev);
+
+	return sprintf(buf, "serio:ty%02Xpr%02Xid%02Xex%02X\n",
+			serio->id.type, serio->id.proto, serio->id.id, serio->id.extra);
+}
 
-        if (serio->dev && serio->dev->interrupt) {
-                ret = serio->dev->interrupt(serio, data, flags, regs);
+static ssize_t serio_show_id_type(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct serio *serio = to_serio_port(dev);
+	return sprintf(buf, "%02x\n", serio->id.type);
+}
+
+static ssize_t serio_show_id_proto(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct serio *serio = to_serio_port(dev);
+	return sprintf(buf, "%02x\n", serio->id.proto);
+}
+
+static ssize_t serio_show_id_id(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct serio *serio = to_serio_port(dev);
+	return sprintf(buf, "%02x\n", serio->id.id);
+}
+
+static ssize_t serio_show_id_extra(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct serio *serio = to_serio_port(dev);
+	return sprintf(buf, "%02x\n", serio->id.extra);
+}
+
+static DEVICE_ATTR(type, S_IRUGO, serio_show_id_type, NULL);
+static DEVICE_ATTR(proto, S_IRUGO, serio_show_id_proto, NULL);
+static DEVICE_ATTR(id, S_IRUGO, serio_show_id_id, NULL);
+static DEVICE_ATTR(extra, S_IRUGO, serio_show_id_extra, NULL);
+
+static struct attribute *serio_device_id_attrs[] = {
+	&dev_attr_type.attr,
+	&dev_attr_proto.attr,
+	&dev_attr_id.attr,
+	&dev_attr_extra.attr,
+	NULL
+};
+
+static struct attribute_group serio_id_attr_group = {
+	.name	= "id",
+	.attrs	= serio_device_id_attrs,
+};
+
+static ssize_t serio_rebind_driver(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct serio *serio = to_serio_port(dev);
+	struct device_driver *drv;
+	int retval;
+
+	retval = mutex_lock_interruptible(&serio_mutex);
+	if (retval)
+		return retval;
+
+	retval = count;
+	if (!strncmp(buf, "none", count)) {
+		serio_disconnect_port(serio);
+	} else if (!strncmp(buf, "reconnect", count)) {
+		serio_reconnect_port(serio);
+	} else if (!strncmp(buf, "rescan", count)) {
+		serio_disconnect_port(serio);
+		serio_find_driver(serio);
+	} else if ((drv = driver_find(buf, &serio_bus)) != NULL) {
+		serio_disconnect_port(serio);
+		serio_bind_driver(serio, to_serio_driver(drv));
+		put_driver(drv);
 	} else {
-		if (!flags) {
-			if ((serio->type == SERIO_8042 ||
-				serio->type == SERIO_8042_XL) && (data != 0xaa))
-					return ret;
-			serio_rescan(serio);
-			ret = IRQ_HANDLED;
-		}
+		retval = -EINVAL;
 	}
-	return ret;
+
+	mutex_unlock(&serio_mutex);
+
+	return retval;
+}
+
+static ssize_t serio_show_bind_mode(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct serio *serio = to_serio_port(dev);
+	return sprintf(buf, "%s\n", serio->manual_bind ? "manual" : "auto");
 }
 
-void serio_register_port(struct serio *serio)
+static ssize_t serio_set_bind_mode(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
 {
-	down(&serio_sem);
-	__serio_register_port(serio);
-	up(&serio_sem);
+	struct serio *serio = to_serio_port(dev);
+	int retval;
+
+	retval = count;
+	if (!strncmp(buf, "manual", count)) {
+		serio->manual_bind = 1;
+	} else if (!strncmp(buf, "auto", count)) {
+		serio->manual_bind = 0;
+	} else {
+		retval = -EINVAL;
+	}
+
+	return retval;
+}
+
+static struct device_attribute serio_device_attrs[] = {
+	__ATTR(description, S_IRUGO, serio_show_description, NULL),
+	__ATTR(modalias, S_IRUGO, serio_show_modalias, NULL),
+	__ATTR(drvctl, S_IWUSR, NULL, serio_rebind_driver),
+	__ATTR(bind_mode, S_IWUSR | S_IRUGO, serio_show_bind_mode, serio_set_bind_mode),
+	__ATTR_NULL
+};
+
+
+static void serio_release_port(struct device *dev)
+{
+	struct serio *serio = to_serio_port(dev);
+
+	kfree(serio);
+	module_put(THIS_MODULE);
 }
 
 /*
- * Submits register request to kseriod for subsequent execution.
- * Can be used when it is not obvious whether the serio_sem is
- * taken or not and when delayed execution is feasible.
+ * Prepare serio port for registration.
  */
-void serio_register_port_delayed(struct serio *serio)
+static void serio_init_port(struct serio *serio)
 {
-	serio_queue_event(serio, SERIO_REGISTER_PORT);
+	static atomic_t serio_no = ATOMIC_INIT(0);
+
+	__module_get(THIS_MODULE);
+
+	INIT_LIST_HEAD(&serio->node);
+	spin_lock_init(&serio->lock);
+	mutex_init(&serio->drv_mutex);
+	device_initialize(&serio->dev);
+	snprintf(serio->dev.bus_id, sizeof(serio->dev.bus_id),
+		 "serio%ld", (long)atomic_inc_return(&serio_no) - 1);
+	serio->dev.bus = &serio_bus;
+	serio->dev.release = serio_release_port;
+	if (serio->parent) {
+		serio->dev.parent = &serio->parent->dev;
+		serio->depth = serio->parent->depth + 1;
+	} else
+		serio->depth = 0;
+	lockdep_set_subclass(&serio->lock, serio->depth);
 }
 
 /*
- * Should only be called directly if serio_sem has already been taken,
- * for example when unregistering a serio from other input device's
- * connect() function.
+ * Complete serio port registration.
+ * Driver core will attempt to find appropriate driver for the port.
  */
-void __serio_register_port(struct serio *serio)
+static void serio_add_port(struct serio *serio)
 {
+	int error;
+
+	if (serio->parent) {
+		serio_pause_rx(serio->parent);
+		serio->parent->child = serio;
+		serio_continue_rx(serio->parent);
+	}
+
 	list_add_tail(&serio->node, &serio_list);
-	serio_find_dev(serio);
+	if (serio->start)
+		serio->start(serio);
+	error = device_add(&serio->dev);
+	if (error)
+		printk(KERN_ERR
+			"serio: device_add() failed for %s (%s), error: %d\n",
+			serio->phys, serio->name, error);
+	else {
+		serio->registered = 1;
+		error = sysfs_create_group(&serio->dev.kobj, &serio_id_attr_group);
+		if (error)
+			printk(KERN_ERR
+				"serio: sysfs_create_group() failed for %s (%s), error: %d\n",
+				serio->phys, serio->name, error);
+	}
+}
+
+/*
+ * serio_destroy_port() completes deregistration process and removes
+ * port from the system
+ */
+static void serio_destroy_port(struct serio *serio)
+{
+	struct serio *child;
+
+	child = serio_get_pending_child(serio);
+	if (child) {
+		serio_remove_pending_events(child);
+		put_device(&child->dev);
+	}
+
+	if (serio->stop)
+		serio->stop(serio);
+
+	if (serio->parent) {
+		serio_pause_rx(serio->parent);
+		serio->parent->child = NULL;
+		serio_continue_rx(serio->parent);
+		serio->parent = NULL;
+	}
+
+	if (serio->registered) {
+		sysfs_remove_group(&serio->dev.kobj, &serio_id_attr_group);
+		device_del(&serio->dev);
+		serio->registered = 0;
+	}
+
+	list_del_init(&serio->node);
+	serio_remove_pending_events(serio);
+	put_device(&serio->dev);
+}
+
+/*
+ * Reconnect serio port and all its children (re-initialize attached devices)
+ */
+static void serio_reconnect_port(struct serio *serio)
+{
+	do {
+		if (serio_reconnect_driver(serio)) {
+			serio_disconnect_port(serio);
+			serio_find_driver(serio);
+			/* Ok, old children are now gone, we are done */
+			break;
+		}
+		serio = serio->child;
+	} while (serio);
+}
+
+/*
+ * serio_disconnect_port() unbinds a port from its driver. As a side effect
+ * all child ports are unbound and destroyed.
+ */
+static void serio_disconnect_port(struct serio *serio)
+{
+	struct serio *s, *parent;
+
+	if (serio->child) {
+		/*
+		 * Children ports should be disconnected and destroyed
+		 * first, staring with the leaf one, since we don't want
+		 * to do recursion
+		 */
+		for (s = serio; s->child; s = s->child)
+			/* empty */;
+
+		do {
+			parent = s->parent;
+
+			serio_release_driver(s);
+			serio_destroy_port(s);
+		} while ((s = parent) != serio);
+	}
+
+	/*
+	 * Ok, no children left, now disconnect this port
+	 */
+	serio_release_driver(serio);
 }
 
+void serio_rescan(struct serio *serio)
+{
+	serio_queue_event(serio, NULL, SERIO_RESCAN_PORT);
+}
+
+void serio_reconnect(struct serio *serio)
+{
+	serio_queue_event(serio, NULL, SERIO_RECONNECT_PORT);
+}
+
+/*
+ * Submits register request to kseriod for subsequent execution.
+ * Note that port registration is always asynchronous.
+ */
+void __serio_register_port(struct serio *serio, struct module *owner)
+{
+	serio_init_port(serio);
+	serio_queue_event(serio, owner, SERIO_REGISTER_PORT);
+}
+
+/*
+ * Synchronously unregisters serio port.
+ */
 void serio_unregister_port(struct serio *serio)
 {
-	down(&serio_sem);
-	__serio_unregister_port(serio);
-	up(&serio_sem);
+	mutex_lock(&serio_mutex);
+	serio_disconnect_port(serio);
+	serio_destroy_port(serio);
+	mutex_unlock(&serio_mutex);
 }
 
 /*
- * Submits unregister request to kseriod for subsequent execution.
- * Can be used when it is not obvious whether the serio_sem is
- * taken or not and when delayed execution is feasible.
+ * Safely unregisters child port if one is present.
  */
-void serio_unregister_port_delayed(struct serio *serio)
+void serio_unregister_child_port(struct serio *serio)
 {
-	serio_queue_event(serio, SERIO_UNREGISTER_PORT);
+	mutex_lock(&serio_mutex);
+	if (serio->child) {
+		serio_disconnect_port(serio->child);
+		serio_destroy_port(serio->child);
+	}
+	mutex_unlock(&serio_mutex);
 }
 
+
 /*
- * Should only be called directly if serio_sem has already been taken,
- * for example when unregistering a serio from other input device's
- * disconnect() function.
+ * Serio driver operations
  */
-void __serio_unregister_port(struct serio *serio)
+
+static ssize_t serio_driver_show_description(struct device_driver *drv, char *buf)
 {
-	serio_invalidate_pending_events(serio);
-	list_del_init(&serio->node);
-	if (serio->dev && serio->dev->disconnect)
-		serio->dev->disconnect(serio);
+	struct serio_driver *driver = to_serio_driver(drv);
+	return sprintf(buf, "%s\n", driver->description ? driver->description : "(none)");
 }
 
-void serio_register_device(struct serio_dev *dev)
+static ssize_t serio_driver_show_bind_mode(struct device_driver *drv, char *buf)
 {
-	struct serio *serio;
-	down(&serio_sem);
-	list_add_tail(&dev->node, &serio_dev_list);
-	list_for_each_entry(serio, &serio_list, node)
-		if (!serio->dev && dev->connect)
-			dev->connect(serio, dev);
-	up(&serio_sem);
+	struct serio_driver *serio_drv = to_serio_driver(drv);
+	return sprintf(buf, "%s\n", serio_drv->manual_bind ? "manual" : "auto");
+}
+
+static ssize_t serio_driver_set_bind_mode(struct device_driver *drv, const char *buf, size_t count)
+{
+	struct serio_driver *serio_drv = to_serio_driver(drv);
+	int retval;
+
+	retval = count;
+	if (!strncmp(buf, "manual", count)) {
+		serio_drv->manual_bind = 1;
+	} else if (!strncmp(buf, "auto", count)) {
+		serio_drv->manual_bind = 0;
+	} else {
+		retval = -EINVAL;
+	}
+
+	return retval;
+}
+
+
+static struct driver_attribute serio_driver_attrs[] = {
+	__ATTR(description, S_IRUGO, serio_driver_show_description, NULL),
+	__ATTR(bind_mode, S_IWUSR | S_IRUGO,
+		serio_driver_show_bind_mode, serio_driver_set_bind_mode),
+	__ATTR_NULL
+};
+
+static int serio_driver_probe(struct device *dev)
+{
+	struct serio *serio = to_serio_port(dev);
+	struct serio_driver *drv = to_serio_driver(dev->driver);
+
+	return serio_connect_driver(serio, drv);
 }
 
-void serio_unregister_device(struct serio_dev *dev)
+static int serio_driver_remove(struct device *dev)
+{
+	struct serio *serio = to_serio_port(dev);
+
+	serio_disconnect_driver(serio);
+	return 0;
+}
+
+static void serio_attach_driver(struct serio_driver *drv)
+{
+	int error;
+
+	error = driver_attach(&drv->driver);
+	if (error)
+		printk(KERN_WARNING
+			"serio: driver_attach() failed for %s with error %d\n",
+			drv->driver.name, error);
+}
+
+int serio_register_driver(struct serio_driver *drv)
+{
+	int manual_bind = drv->manual_bind;
+	int error;
+
+	drv->driver.bus = &serio_bus;
+
+	/*
+	 * Temporarily disable automatic binding because probing
+	 * takes long time and we are better off doing it in kseriod
+	 */
+	drv->manual_bind = 1;
+
+	error = driver_register(&drv->driver);
+	if (error) {
+		printk(KERN_ERR
+			"serio: driver_register() failed for %s, error: %d\n",
+			drv->driver.name, error);
+		return error;
+	}
+
+	/*
+	 * Restore original bind mode and let kseriod bind the
+	 * driver to free ports
+	 */
+	if (!manual_bind) {
+		drv->manual_bind = 0;
+		error = serio_queue_event(drv, NULL, SERIO_ATTACH_DRIVER);
+		if (error) {
+			driver_unregister(&drv->driver);
+			return error;
+		}
+	}
+
+	return 0;
+}
+
+void serio_unregister_driver(struct serio_driver *drv)
 {
 	struct serio *serio;
 
-	down(&serio_sem);
-	list_del_init(&dev->node);
+	mutex_lock(&serio_mutex);
+	drv->manual_bind = 1;	/* so serio_find_driver ignores it */
 
+start_over:
 	list_for_each_entry(serio, &serio_list, node) {
-		if (serio->dev == dev && dev->disconnect)
-			dev->disconnect(serio);
-		serio_find_dev(serio);
+		if (serio->drv == drv) {
+			serio_disconnect_port(serio);
+			serio_find_driver(serio);
+			/* we could've deleted some ports, restart */
+			goto start_over;
+		}
+	}
+
+	driver_unregister(&drv->driver);
+	mutex_unlock(&serio_mutex);
+}
+
+static void serio_set_drv(struct serio *serio, struct serio_driver *drv)
+{
+	serio_pause_rx(serio);
+	serio->drv = drv;
+	serio_continue_rx(serio);
+}
+
+static int serio_bus_match(struct device *dev, struct device_driver *drv)
+{
+	struct serio *serio = to_serio_port(dev);
+	struct serio_driver *serio_drv = to_serio_driver(drv);
+
+	if (serio->manual_bind || serio_drv->manual_bind)
+		return 0;
+
+	return serio_match_port(serio_drv->id_table, serio);
+}
+
+#ifdef CONFIG_HOTPLUG
+
+#define SERIO_ADD_UEVENT_VAR(fmt, val...)				\
+	do {								\
+		int err = add_uevent_var(envp, num_envp, &i,	\
+					buffer, buffer_size, &len,	\
+					fmt, val);			\
+		if (err)						\
+			return err;					\
+	} while (0)
+
+static int serio_uevent(struct device *dev, char **envp, int num_envp, char *buffer, int buffer_size)
+{
+	struct serio *serio;
+	int i = 0;
+	int len = 0;
+
+	if (!dev)
+		return -ENODEV;
+
+	serio = to_serio_port(dev);
+
+	SERIO_ADD_UEVENT_VAR("SERIO_TYPE=%02x", serio->id.type);
+	SERIO_ADD_UEVENT_VAR("SERIO_PROTO=%02x", serio->id.proto);
+	SERIO_ADD_UEVENT_VAR("SERIO_ID=%02x", serio->id.id);
+	SERIO_ADD_UEVENT_VAR("SERIO_EXTRA=%02x", serio->id.extra);
+	SERIO_ADD_UEVENT_VAR("MODALIAS=serio:ty%02Xpr%02Xid%02Xex%02X",
+				serio->id.type, serio->id.proto, serio->id.id, serio->id.extra);
+	envp[i] = NULL;
+
+	return 0;
+}
+#undef SERIO_ADD_UEVENT_VAR
+
+#else
+
+static int serio_uevent(struct device *dev, char **envp, int num_envp, char *buffer, int buffer_size)
+{
+	return -ENODEV;
+}
+
+#endif /* CONFIG_HOTPLUG */
+
+static int serio_resume(struct device *dev)
+{
+	struct serio *serio = to_serio_port(dev);
+
+	if (serio_reconnect_driver(serio)) {
+		/*
+		 * Driver re-probing can take a while, so better let kseriod
+		 * deal with it.
+		 */
+		serio_rescan(serio);
 	}
-	up(&serio_sem);
+
+	return 0;
 }
 
-/* called from serio_dev->connect/disconnect methods under serio_sem */
-int serio_open(struct serio *serio, struct serio_dev *dev)
+/* called from serio_driver->connect/disconnect methods under serio_mutex */
+int serio_open(struct serio *serio, struct serio_driver *drv)
 {
-	serio->dev = dev;
+	serio_set_drv(serio, drv);
+
 	if (serio->open && serio->open(serio)) {
-		serio->dev = NULL;
+		serio_set_drv(serio, NULL);
 		return -1;
 	}
 	return 0;
 }
 
-/* called from serio_dev->connect/disconnect methods under serio_sem */
+/* called from serio_driver->connect/disconnect methods under serio_mutex */
 void serio_close(struct serio *serio)
 {
 	if (serio->close)
 		serio->close(serio);
-	serio->dev = NULL;
+
+	serio_set_drv(serio, NULL);
 }
 
-static int __init serio_init(void)
+irqreturn_t serio_interrupt(struct serio *serio,
+		unsigned char data, unsigned int dfl)
 {
-	int pid;
+	unsigned long flags;
+	irqreturn_t ret = IRQ_NONE;
 
-	pid = kernel_thread(serio_thread, NULL, CLONE_KERNEL);
+	spin_lock_irqsave(&serio->lock, flags);
 
-	if (!pid) {
-		printk(KERN_WARNING "serio: Failed to start kseriod\n");
-		return -1;
+        if (likely(serio->drv)) {
+                ret = serio->drv->interrupt(serio, data, dfl);
+	} else if (!dfl && serio->registered) {
+		serio_rescan(serio);
+		ret = IRQ_HANDLED;
+	}
+
+	spin_unlock_irqrestore(&serio->lock, flags);
+
+	return ret;
+}
+
+static struct bus_type serio_bus = {
+	.name		= "serio",
+	.dev_attrs	= serio_device_attrs,
+	.drv_attrs	= serio_driver_attrs,
+	.match		= serio_bus_match,
+	.uevent		= serio_uevent,
+	.probe		= serio_driver_probe,
+	.remove		= serio_driver_remove,
+	.resume		= serio_resume,
+};
+
+static int __init serio_init(void)
+{
+	int error;
+
+	error = bus_register(&serio_bus);
+	if (error) {
+		printk(KERN_ERR "serio: failed to register serio bus, error: %d\n", error);
+		return error;
 	}
 
-	serio_pid = pid;
+	serio_task = kthread_run(serio_thread, NULL, "kseriod");
+	if (IS_ERR(serio_task)) {
+		bus_unregister(&serio_bus);
+		error = PTR_ERR(serio_task);
+		printk(KERN_ERR "serio: Failed to start kseriod, error: %d\n", error);
+		return error;
+	}
 
 	return 0;
 }
 
 static void __exit serio_exit(void)
 {
-	kill_proc(serio_pid, SIGTERM, 1);
-	wait_for_completion(&serio_exited);
+	bus_unregister(&serio_bus);
+	kthread_stop(serio_task);
 }
 
-module_init(serio_init);
+subsys_initcall(serio_init);
 module_exit(serio_exit);