linux/drivers/input/serio/serio.c
Rafael J. Wysocki e42837bcd3 freezer: introduce freezer-friendly waiting macros
Introduce freezer-friendly wrappers around wait_event_interruptible() and
wait_event_interruptible_timeout(), originally defined in <linux/wait.h>, to
be used in freezable kernel threads.  Make some of the freezable kernel
threads use them.

This is necessary for the freezer to stop sending signals to kernel threads,
which is implemented in the next patch.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: Nigel Cunningham <nigel@nigel.suspend2.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-18 14:37:19 -07:00

1029 lines
24 KiB
C

/*
* The Serio abstraction module
*
* Copyright (c) 1999-2004 Vojtech Pavlik
* Copyright (c) 2004 Dmitry Torokhov
* Copyright (c) 2003 Daniele Bellucci
*/
/*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* 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
*/
#include <linux/stddef.h>
#include <linux/module.h>
#include <linux/serio.h>
#include <linux/errno.h>
#include <linux/wait.h>
#include <linux/sched.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_unregister_port);
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 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) {
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;
return error;
}
}
return 0;
}
static void serio_find_driver(struct serio *serio)
{
int error;
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);
}
/*
* Serio event processing.
*/
enum serio_event_type {
SERIO_RESCAN_PORT,
SERIO_RECONNECT_PORT,
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 DECLARE_WAIT_QUEUE_HEAD(serio_wait);
static struct task_struct *serio_task;
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) {
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;
}
static void serio_free_event(struct serio_event *event)
{
module_put(event->owner);
kfree(event);
}
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);
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);
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;
}
static void serio_handle_event(void)
{
struct serio_event *event;
mutex_lock(&serio_mutex);
/*
* 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_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_ATTACH_DRIVER:
serio_attach_driver(event->object);
break;
default:
break;
}
serio_remove_duplicate_events(event);
serio_free_event(event);
}
mutex_unlock(&serio_mutex);
}
/*
* Remove all events that have been submitted for a given serio port.
*/
static void serio_remove_pending_events(struct serio *serio)
{
struct list_head *node, *next;
struct serio_event *event;
unsigned long flags;
spin_lock_irqsave(&serio_event_lock, flags);
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);
}
}
spin_unlock_irqrestore(&serio_event_lock, flags);
}
/*
* 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;
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;
}
static int serio_thread(void *nothing)
{
set_freezable();
do {
serio_handle_event();
wait_event_freezable(serio_wait,
kthread_should_stop() || !list_empty(&serio_event_list));
} while (!kthread_should_stop());
printk(KERN_DEBUG "serio: kseriod exiting\n");
return 0;
}
/*
* 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 serio_show_modalias(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 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 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_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);
error = serio_bind_driver(serio, to_serio_driver(drv));
put_driver(drv);
} 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 = 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);
}
/*
* Prepare serio port for registration.
*/
static void serio_init_port(struct serio *serio)
{
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);
}
/*
* Complete serio port registration.
* Driver core will attempt to find appropriate driver for the port.
*/
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);
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;
device_release_driver(&s->dev);
serio_destroy_port(s);
} while ((s = parent) != serio);
}
/*
* 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);
}
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)
{
mutex_lock(&serio_mutex);
serio_disconnect_port(serio);
serio_destroy_port(serio);
mutex_unlock(&serio_mutex);
}
/*
* Safely unregisters child port if one is present.
*/
void serio_unregister_child_port(struct serio *serio)
{
mutex_lock(&serio_mutex);
if (serio->child) {
serio_disconnect_port(serio->child);
serio_destroy_port(serio->child);
}
mutex_unlock(&serio_mutex);
}
/*
* Serio driver operations
*/
static ssize_t serio_driver_show_description(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 ssize_t serio_driver_show_bind_mode(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 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);
}
static int serio_driver_remove(struct device *dev)
{
struct serio *serio = to_serio_port(dev);
serio_disconnect_driver(serio);
return 0;
}
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)
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, struct module *owner, const char *mod_name)
{
int 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 = 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;
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->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(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);
return 0;
}
#undef SERIO_ADD_UEVENT_VAR
#else
static int serio_uevent(struct device *dev, struct kobj_uevent_env *env)
{
return -ENODEV;
}
#endif /* CONFIG_HOTPLUG */
#ifdef CONFIG_PM
static int serio_suspend(struct device *dev, pm_message_t state)
{
if (dev->power.power_state.event != state.event) {
if (state.event == PM_EVENT_SUSPEND)
serio_cleanup(to_serio_port(dev));
dev->power.power_state = state;
}
return 0;
}
static int serio_resume(struct device *dev)
{
struct serio *serio = to_serio_port(dev);
if (dev->power.power_state.event != PM_EVENT_ON &&
serio_reconnect_driver(serio)) {
/*
* Driver re-probing can take a while, so better let kseriod
* deal with it.
*/
serio_rescan(serio);
}
dev->power.power_state = PMSG_ON;
return 0;
}
#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;
}
/* 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);
}
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 && 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,
.shutdown = serio_shutdown,
#ifdef CONFIG_PM
.suspend = serio_suspend,
.resume = serio_resume,
#endif
};
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_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)
{
bus_unregister(&serio_bus);
kthread_stop(serio_task);
}
subsys_initcall(serio_init);
module_exit(serio_exit);