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-rw-r--r--drivers/input/serio/serio.c1049
1 files changed, 1049 insertions, 0 deletions
diff --git a/drivers/input/serio/serio.c b/drivers/input/serio/serio.c
new file mode 100644
index 000000000..15ce32023
--- /dev/null
+++ b/drivers/input/serio/serio.c
@@ -0,0 +1,1049 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * The Serio abstraction module
+ *
+ * Copyright (c) 1999-2004 Vojtech Pavlik
+ * Copyright (c) 2004 Dmitry Torokhov
+ * Copyright (c) 2003 Daniele Bellucci
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/stddef.h>
+#include <linux/module.h>
+#include <linux/serio.h>
+#include <linux/errno.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/workqueue.h>
+#include <linux/mutex.h>
+
+MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
+MODULE_DESCRIPTION("Serio abstraction core");
+MODULE_LICENSE("GPL");
+
+/*
+ * serio_mutex protects entire serio subsystem and is taken every time
+ * serio port or driver registered or unregistered.
+ */
+static DEFINE_MUTEX(serio_mutex);
+
+static LIST_HEAD(serio_list);
+
+static void serio_add_port(struct serio *serio);
+static int serio_reconnect_port(struct serio *serio);
+static void serio_disconnect_port(struct serio *serio);
+static void serio_reconnect_subtree(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 int serio_bind_driver(struct serio *serio, struct serio_driver *drv)
+{
+ int error;
+
+ if (serio_match_port(drv->id_table, serio)) {
+
+ serio->dev.driver = &drv->driver;
+ if (serio_connect_driver(serio, drv)) {
+ serio->dev.driver = NULL;
+ return -ENODEV;
+ }
+
+ error = device_bind_driver(&serio->dev);
+ if (error) {
+ dev_warn(&serio->dev,
+ "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;
+ return error;
+ }
+ }
+ return 0;
+}
+
+static void serio_find_driver(struct serio *serio)
+{
+ int error;
+
+ error = device_attach(&serio->dev);
+ if (error < 0 && error != -EPROBE_DEFER)
+ dev_warn(&serio->dev,
+ "device_attach() failed for %s (%s), error: %d\n",
+ serio->phys, serio->name, error);
+}
+
+
+/*
+ * Serio event processing.
+ */
+
+enum serio_event_type {
+ SERIO_RESCAN_PORT,
+ SERIO_RECONNECT_PORT,
+ SERIO_RECONNECT_SUBTREE,
+ SERIO_REGISTER_PORT,
+ SERIO_ATTACH_DRIVER,
+};
+
+struct serio_event {
+ enum serio_event_type type;
+ void *object;
+ struct module *owner;
+ struct list_head node;
+};
+
+static DEFINE_SPINLOCK(serio_event_lock); /* protects serio_event_list */
+static LIST_HEAD(serio_event_list);
+
+static struct serio_event *serio_get_event(void)
+{
+ struct serio_event *event = NULL;
+ unsigned long flags;
+
+ spin_lock_irqsave(&serio_event_lock, flags);
+
+ if (!list_empty(&serio_event_list)) {
+ event = list_first_entry(&serio_event_list,
+ struct serio_event, node);
+ list_del_init(&event->node);
+ }
+
+ spin_unlock_irqrestore(&serio_event_lock, flags);
+ return event;
+}
+
+static void serio_free_event(struct serio_event *event)
+{
+ module_put(event->owner);
+ kfree(event);
+}
+
+static void serio_remove_duplicate_events(void *object,
+ enum serio_event_type type)
+{
+ struct serio_event *e, *next;
+ unsigned long flags;
+
+ spin_lock_irqsave(&serio_event_lock, flags);
+
+ list_for_each_entry_safe(e, next, &serio_event_list, node) {
+ if (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 (type != e->type)
+ break;
+
+ list_del_init(&e->node);
+ serio_free_event(e);
+ }
+ }
+
+ spin_unlock_irqrestore(&serio_event_lock, flags);
+}
+
+static void serio_handle_event(struct work_struct *work)
+{
+ struct serio_event *event;
+
+ mutex_lock(&serio_mutex);
+
+ while ((event = serio_get_event())) {
+
+ switch (event->type) {
+
+ case SERIO_REGISTER_PORT:
+ serio_add_port(event->object);
+ break;
+
+ case SERIO_RECONNECT_PORT:
+ serio_reconnect_port(event->object);
+ break;
+
+ case SERIO_RESCAN_PORT:
+ serio_disconnect_port(event->object);
+ serio_find_driver(event->object);
+ break;
+
+ case SERIO_RECONNECT_SUBTREE:
+ serio_reconnect_subtree(event->object);
+ break;
+
+ case SERIO_ATTACH_DRIVER:
+ serio_attach_driver(event->object);
+ break;
+ }
+
+ serio_remove_duplicate_events(event->object, event->type);
+ serio_free_event(event);
+ }
+
+ mutex_unlock(&serio_mutex);
+}
+
+static DECLARE_WORK(serio_event_work, serio_handle_event);
+
+static int serio_queue_event(void *object, struct module *owner,
+ enum serio_event_type event_type)
+{
+ 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;
+ }
+ }
+
+ event = kmalloc(sizeof(struct serio_event), GFP_ATOMIC);
+ if (!event) {
+ pr_err("Not enough memory to queue event %d\n", event_type);
+ retval = -ENOMEM;
+ goto out;
+ }
+
+ if (!try_module_get(owner)) {
+ pr_warn("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);
+ queue_work(system_long_wq, &serio_event_work);
+
+out:
+ spin_unlock_irqrestore(&serio_event_lock, flags);
+ return retval;
+}
+
+/*
+ * Remove all events that have been submitted for a given
+ * object, be it serio port or driver.
+ */
+static void serio_remove_pending_events(void *object)
+{
+ struct serio_event *event, *next;
+ unsigned long flags;
+
+ spin_lock_irqsave(&serio_event_lock, flags);
+
+ list_for_each_entry_safe(event, next, &serio_event_list, node) {
+ if (event->object == object) {
+ list_del_init(&event->node);
+ serio_free_event(event);
+ }
+ }
+
+ spin_unlock_irqrestore(&serio_event_lock, flags);
+}
+
+/*
+ * Locate child serio port (if any) that has not been fully registered yet.
+ *
+ * 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;
+
+ spin_lock_irqsave(&serio_event_lock, flags);
+
+ 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;
+}
+
+/*
+ * Serio port operations
+ */
+
+static ssize_t serio_show_description(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ struct serio *serio = to_serio_port(dev);
+ return sprintf(buf, "%s\n", serio->name);
+}
+
+static ssize_t modalias_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ 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);
+}
+
+static ssize_t type_show(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 proto_show(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 id_show(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 extra_show(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 ssize_t drvctl_store(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 error;
+
+ error = mutex_lock_interruptible(&serio_mutex);
+ if (error)
+ return error;
+
+ if (!strncmp(buf, "none", count)) {
+ serio_disconnect_port(serio);
+ } else if (!strncmp(buf, "reconnect", count)) {
+ serio_reconnect_subtree(serio);
+ } else if (!strncmp(buf, "rescan", count)) {
+ serio_disconnect_port(serio);
+ serio_find_driver(serio);
+ serio_remove_duplicate_events(serio, SERIO_RESCAN_PORT);
+ } else if ((drv = driver_find(buf, &serio_bus)) != NULL) {
+ serio_disconnect_port(serio);
+ error = serio_bind_driver(serio, to_serio_driver(drv));
+ serio_remove_duplicate_events(serio, SERIO_RESCAN_PORT);
+ } else {
+ error = -EINVAL;
+ }
+
+ mutex_unlock(&serio_mutex);
+
+ return error ? error : count;
+}
+
+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");
+}
+
+static ssize_t serio_set_bind_mode(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
+{
+ struct serio *serio = to_serio_port(dev);
+ int retval;
+
+ retval = count;
+ if (!strncmp(buf, "manual", count)) {
+ serio->manual_bind = true;
+ } else if (!strncmp(buf, "auto", count)) {
+ serio->manual_bind = false;
+ } else {
+ retval = -EINVAL;
+ }
+
+ return retval;
+}
+
+static ssize_t firmware_id_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ struct serio *serio = to_serio_port(dev);
+
+ return sprintf(buf, "%s\n", serio->firmware_id);
+}
+
+static DEVICE_ATTR_RO(type);
+static DEVICE_ATTR_RO(proto);
+static DEVICE_ATTR_RO(id);
+static DEVICE_ATTR_RO(extra);
+
+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 const struct attribute_group serio_id_attr_group = {
+ .name = "id",
+ .attrs = serio_device_id_attrs,
+};
+
+static DEVICE_ATTR_RO(modalias);
+static DEVICE_ATTR_WO(drvctl);
+static DEVICE_ATTR(description, S_IRUGO, serio_show_description, NULL);
+static DEVICE_ATTR(bind_mode, S_IWUSR | S_IRUGO, serio_show_bind_mode, serio_set_bind_mode);
+static DEVICE_ATTR_RO(firmware_id);
+
+static struct attribute *serio_device_attrs[] = {
+ &dev_attr_modalias.attr,
+ &dev_attr_description.attr,
+ &dev_attr_drvctl.attr,
+ &dev_attr_bind_mode.attr,
+ &dev_attr_firmware_id.attr,
+ NULL
+};
+
+static const struct attribute_group serio_device_attr_group = {
+ .attrs = serio_device_attrs,
+};
+
+static const struct attribute_group *serio_device_attr_groups[] = {
+ &serio_id_attr_group,
+ &serio_device_attr_group,
+ NULL
+};
+
+static void serio_release_port(struct device *dev)
+{
+ struct serio *serio = to_serio_port(dev);
+
+ kfree(serio);
+ module_put(THIS_MODULE);
+}
+
+/*
+ * Prepare serio port for registration.
+ */
+static void serio_init_port(struct serio *serio)
+{
+ static atomic_t serio_no = ATOMIC_INIT(-1);
+
+ __module_get(THIS_MODULE);
+
+ INIT_LIST_HEAD(&serio->node);
+ INIT_LIST_HEAD(&serio->child_node);
+ INIT_LIST_HEAD(&serio->children);
+ spin_lock_init(&serio->lock);
+ mutex_init(&serio->drv_mutex);
+ device_initialize(&serio->dev);
+ dev_set_name(&serio->dev, "serio%lu",
+ (unsigned long)atomic_inc_return(&serio_no));
+ serio->dev.bus = &serio_bus;
+ serio->dev.release = serio_release_port;
+ serio->dev.groups = serio_device_attr_groups;
+ 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);
+}
+
+/*
+ * Complete serio port registration.
+ * Driver core will attempt to find appropriate driver for the port.
+ */
+static void serio_add_port(struct serio *serio)
+{
+ struct serio *parent = serio->parent;
+ int error;
+
+ if (parent) {
+ serio_pause_rx(parent);
+ list_add_tail(&serio->child_node, &parent->children);
+ serio_continue_rx(parent);
+ }
+
+ list_add_tail(&serio->node, &serio_list);
+
+ if (serio->start)
+ serio->start(serio);
+
+ error = device_add(&serio->dev);
+ if (error)
+ dev_err(&serio->dev,
+ "device_add() failed for %s (%s), error: %d\n",
+ serio->phys, serio->name, error);
+}
+
+/*
+ * serio_destroy_port() completes unregistration process and removes
+ * port from the system
+ */
+static void serio_destroy_port(struct serio *serio)
+{
+ struct serio *child;
+
+ while ((child = serio_get_pending_child(serio)) != NULL) {
+ serio_remove_pending_events(child);
+ put_device(&child->dev);
+ }
+
+ if (serio->stop)
+ serio->stop(serio);
+
+ if (serio->parent) {
+ serio_pause_rx(serio->parent);
+ list_del_init(&serio->child_node);
+ serio_continue_rx(serio->parent);
+ serio->parent = NULL;
+ }
+
+ if (device_is_registered(&serio->dev))
+ device_del(&serio->dev);
+
+ list_del_init(&serio->node);
+ serio_remove_pending_events(serio);
+ put_device(&serio->dev);
+}
+
+/*
+ * Reconnect serio port (re-initialize attached device).
+ * If reconnect fails (old device is no longer attached or
+ * there was no device to begin with) we do full rescan in
+ * hope of finding a driver for the port.
+ */
+static int serio_reconnect_port(struct serio *serio)
+{
+ int error = serio_reconnect_driver(serio);
+
+ if (error) {
+ serio_disconnect_port(serio);
+ serio_find_driver(serio);
+ }
+
+ return error;
+}
+
+/*
+ * Reconnect serio port and all its children (re-initialize attached
+ * devices).
+ */
+static void serio_reconnect_subtree(struct serio *root)
+{
+ struct serio *s = root;
+ int error;
+
+ do {
+ error = serio_reconnect_port(s);
+ if (!error) {
+ /*
+ * Reconnect was successful, move on to do the
+ * first child.
+ */
+ if (!list_empty(&s->children)) {
+ s = list_first_entry(&s->children,
+ struct serio, child_node);
+ continue;
+ }
+ }
+
+ /*
+ * Either it was a leaf node or reconnect failed and it
+ * became a leaf node. Continue reconnecting starting with
+ * the next sibling of the parent node.
+ */
+ while (s != root) {
+ struct serio *parent = s->parent;
+
+ if (!list_is_last(&s->child_node, &parent->children)) {
+ s = list_entry(s->child_node.next,
+ struct serio, child_node);
+ break;
+ }
+
+ s = parent;
+ }
+ } while (s != root);
+}
+
+/*
+ * serio_disconnect_port() unbinds a port from its driver. As a side effect
+ * all children ports are unbound and destroyed.
+ */
+static void serio_disconnect_port(struct serio *serio)
+{
+ struct serio *s = serio;
+
+ /*
+ * Children ports should be disconnected and destroyed
+ * first; we travel the tree in depth-first order.
+ */
+ while (!list_empty(&serio->children)) {
+
+ /* Locate a leaf */
+ while (!list_empty(&s->children))
+ s = list_first_entry(&s->children,
+ struct serio, child_node);
+
+ /*
+ * Prune this leaf node unless it is the one we
+ * started with.
+ */
+ if (s != serio) {
+ struct serio *parent = s->parent;
+
+ device_release_driver(&s->dev);
+ serio_destroy_port(s);
+
+ s = parent;
+ }
+ }
+
+ /*
+ * OK, no children left, now disconnect this port.
+ */
+ device_release_driver(&serio->dev);
+}
+
+void serio_rescan(struct serio *serio)
+{
+ serio_queue_event(serio, NULL, SERIO_RESCAN_PORT);
+}
+EXPORT_SYMBOL(serio_rescan);
+
+void serio_reconnect(struct serio *serio)
+{
+ serio_queue_event(serio, NULL, SERIO_RECONNECT_SUBTREE);
+}
+EXPORT_SYMBOL(serio_reconnect);
+
+/*
+ * 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);
+}
+EXPORT_SYMBOL(__serio_register_port);
+
+/*
+ * Synchronously unregisters serio port.
+ */
+void serio_unregister_port(struct serio *serio)
+{
+ mutex_lock(&serio_mutex);
+ serio_disconnect_port(serio);
+ serio_destroy_port(serio);
+ mutex_unlock(&serio_mutex);
+}
+EXPORT_SYMBOL(serio_unregister_port);
+
+/*
+ * Safely unregisters children ports if they are present.
+ */
+void serio_unregister_child_port(struct serio *serio)
+{
+ struct serio *s, *next;
+
+ mutex_lock(&serio_mutex);
+ list_for_each_entry_safe(s, next, &serio->children, child_node) {
+ serio_disconnect_port(s);
+ serio_destroy_port(s);
+ }
+ mutex_unlock(&serio_mutex);
+}
+EXPORT_SYMBOL(serio_unregister_child_port);
+
+
+/*
+ * Serio driver operations
+ */
+
+static ssize_t description_show(struct device_driver *drv, char *buf)
+{
+ struct serio_driver *driver = to_serio_driver(drv);
+ return sprintf(buf, "%s\n", driver->description ? driver->description : "(none)");
+}
+static DRIVER_ATTR_RO(description);
+
+static ssize_t bind_mode_show(struct device_driver *drv, char *buf)
+{
+ struct serio_driver *serio_drv = to_serio_driver(drv);
+ return sprintf(buf, "%s\n", serio_drv->manual_bind ? "manual" : "auto");
+}
+
+static ssize_t bind_mode_store(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 = true;
+ } else if (!strncmp(buf, "auto", count)) {
+ serio_drv->manual_bind = false;
+ } else {
+ retval = -EINVAL;
+ }
+
+ return retval;
+}
+static DRIVER_ATTR_RW(bind_mode);
+
+static struct attribute *serio_driver_attrs[] = {
+ &driver_attr_description.attr,
+ &driver_attr_bind_mode.attr,
+ NULL,
+};
+ATTRIBUTE_GROUPS(serio_driver);
+
+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);
+}
+
+static void serio_driver_remove(struct device *dev)
+{
+ struct serio *serio = to_serio_port(dev);
+
+ serio_disconnect_driver(serio);
+}
+
+static void serio_cleanup(struct serio *serio)
+{
+ mutex_lock(&serio->drv_mutex);
+ if (serio->drv && serio->drv->cleanup)
+ serio->drv->cleanup(serio);
+ mutex_unlock(&serio->drv_mutex);
+}
+
+static void serio_shutdown(struct device *dev)
+{
+ struct serio *serio = to_serio_port(dev);
+
+ serio_cleanup(serio);
+}
+
+static void serio_attach_driver(struct serio_driver *drv)
+{
+ int error;
+
+ error = driver_attach(&drv->driver);
+ if (error)
+ pr_warn("driver_attach() failed for %s with error %d\n",
+ drv->driver.name, error);
+}
+
+int __serio_register_driver(struct serio_driver *drv, struct module *owner, const char *mod_name)
+{
+ bool manual_bind = drv->manual_bind;
+ int error;
+
+ drv->driver.bus = &serio_bus;
+ drv->driver.owner = owner;
+ drv->driver.mod_name = mod_name;
+
+ /*
+ * Temporarily disable automatic binding because probing
+ * takes long time and we are better off doing it in kseriod
+ */
+ drv->manual_bind = true;
+
+ error = driver_register(&drv->driver);
+ if (error) {
+ pr_err("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 = false;
+ error = serio_queue_event(drv, NULL, SERIO_ATTACH_DRIVER);
+ if (error) {
+ driver_unregister(&drv->driver);
+ return error;
+ }
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL(__serio_register_driver);
+
+void serio_unregister_driver(struct serio_driver *drv)
+{
+ struct serio *serio;
+
+ mutex_lock(&serio_mutex);
+
+ drv->manual_bind = true; /* so serio_find_driver ignores it */
+ serio_remove_pending_events(drv);
+
+start_over:
+ list_for_each_entry(serio, &serio_list, node) {
+ 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);
+}
+EXPORT_SYMBOL(serio_unregister_driver);
+
+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);
+}
+
+#define SERIO_ADD_UEVENT_VAR(fmt, val...) \
+ do { \
+ int err = add_uevent_var(env, fmt, val); \
+ if (err) \
+ return err; \
+ } while (0)
+
+static int serio_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+ struct serio *serio;
+
+ 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);
+
+ if (serio->firmware_id[0])
+ SERIO_ADD_UEVENT_VAR("SERIO_FIRMWARE_ID=%s",
+ serio->firmware_id);
+
+ return 0;
+}
+#undef SERIO_ADD_UEVENT_VAR
+
+#ifdef CONFIG_PM
+static int serio_suspend(struct device *dev)
+{
+ struct serio *serio = to_serio_port(dev);
+
+ serio_cleanup(serio);
+
+ return 0;
+}
+
+static int serio_resume(struct device *dev)
+{
+ struct serio *serio = to_serio_port(dev);
+ int error = -ENOENT;
+
+ mutex_lock(&serio->drv_mutex);
+ if (serio->drv && serio->drv->fast_reconnect) {
+ error = serio->drv->fast_reconnect(serio);
+ if (error && error != -ENOENT)
+ dev_warn(dev, "fast reconnect failed with error %d\n",
+ error);
+ }
+ mutex_unlock(&serio->drv_mutex);
+
+ if (error) {
+ /*
+ * Driver reconnect can take a while, so better let
+ * kseriod deal with it.
+ */
+ serio_queue_event(serio, NULL, SERIO_RECONNECT_PORT);
+ }
+
+ return 0;
+}
+
+static const struct dev_pm_ops serio_pm_ops = {
+ .suspend = serio_suspend,
+ .resume = serio_resume,
+ .poweroff = serio_suspend,
+ .restore = serio_resume,
+};
+#endif /* CONFIG_PM */
+
+/* called from serio_driver->connect/disconnect methods under serio_mutex */
+int serio_open(struct serio *serio, struct serio_driver *drv)
+{
+ serio_set_drv(serio, drv);
+
+ if (serio->open && serio->open(serio)) {
+ serio_set_drv(serio, NULL);
+ return -1;
+ }
+ return 0;
+}
+EXPORT_SYMBOL(serio_open);
+
+/* called from serio_driver->connect/disconnect methods under serio_mutex */
+void serio_close(struct serio *serio)
+{
+ if (serio->close)
+ serio->close(serio);
+
+ serio_set_drv(serio, NULL);
+}
+EXPORT_SYMBOL(serio_close);
+
+irqreturn_t serio_interrupt(struct serio *serio,
+ unsigned char data, unsigned int dfl)
+{
+ unsigned long flags;
+ irqreturn_t ret = IRQ_NONE;
+
+ spin_lock_irqsave(&serio->lock, flags);
+
+ if (likely(serio->drv)) {
+ ret = serio->drv->interrupt(serio, data, dfl);
+ } else if (!dfl && device_is_registered(&serio->dev)) {
+ serio_rescan(serio);
+ ret = IRQ_HANDLED;
+ }
+
+ spin_unlock_irqrestore(&serio->lock, flags);
+
+ return ret;
+}
+EXPORT_SYMBOL(serio_interrupt);
+
+struct bus_type serio_bus = {
+ .name = "serio",
+ .drv_groups = serio_driver_groups,
+ .match = serio_bus_match,
+ .uevent = serio_uevent,
+ .probe = serio_driver_probe,
+ .remove = serio_driver_remove,
+ .shutdown = serio_shutdown,
+#ifdef CONFIG_PM
+ .pm = &serio_pm_ops,
+#endif
+};
+EXPORT_SYMBOL(serio_bus);
+
+static int __init serio_init(void)
+{
+ int error;
+
+ error = bus_register(&serio_bus);
+ if (error) {
+ pr_err("Failed to register serio bus, error: %d\n", error);
+ return error;
+ }
+
+ return 0;
+}
+
+static void __exit serio_exit(void)
+{
+ bus_unregister(&serio_bus);
+
+ /*
+ * There should not be any outstanding events but work may
+ * still be scheduled so simply cancel it.
+ */
+ cancel_work_sync(&serio_event_work);
+}
+
+subsys_initcall(serio_init);
+module_exit(serio_exit);