// 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 <[email protected]>");
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(*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, const struct device_driver *drv)
{
struct serio *serio = to_serio_port(dev);
const 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(const struct device *dev, struct kobj_uevent_env *env)
{
const 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);
const 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);
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