android_kernel_xiaomi_sm8350/drivers/input/gameport/gameport.c
Dmitry Torokhov 4ced8e7cb9 Input: gameport - fix attach driver code
The commit 6902c0bead that moved
driver registration out of kgameportd thread was incomplete and
did not add the code necessary to actually attach driver to
already registered devices, rectify that.

Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2009-04-15 08:58:19 -07:00

855 lines
20 KiB
C

/*
* Generic gameport layer
*
* Copyright (c) 1999-2002 Vojtech Pavlik
* Copyright (c) 2005 Dmitry Torokhov
*/
/*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published by
* the Free Software Foundation.
*/
#include <linux/stddef.h>
#include <linux/module.h>
#include <linux/ioport.h>
#include <linux/init.h>
#include <linux/gameport.h>
#include <linux/wait.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/kthread.h>
#include <linux/sched.h> /* HZ */
#include <linux/mutex.h>
#include <linux/freezer.h>
/*#include <asm/io.h>*/
MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
MODULE_DESCRIPTION("Generic gameport layer");
MODULE_LICENSE("GPL");
EXPORT_SYMBOL(__gameport_register_port);
EXPORT_SYMBOL(gameport_unregister_port);
EXPORT_SYMBOL(__gameport_register_driver);
EXPORT_SYMBOL(gameport_unregister_driver);
EXPORT_SYMBOL(gameport_open);
EXPORT_SYMBOL(gameport_close);
EXPORT_SYMBOL(gameport_set_phys);
EXPORT_SYMBOL(gameport_start_polling);
EXPORT_SYMBOL(gameport_stop_polling);
/*
* gameport_mutex protects entire gameport subsystem and is taken
* every time gameport port or driver registrered or unregistered.
*/
static DEFINE_MUTEX(gameport_mutex);
static LIST_HEAD(gameport_list);
static struct bus_type gameport_bus;
static void gameport_add_port(struct gameport *gameport);
static void gameport_attach_driver(struct gameport_driver *drv);
static void gameport_reconnect_port(struct gameport *gameport);
static void gameport_disconnect_port(struct gameport *gameport);
#if defined(__i386__)
#include <asm/i8253.h>
#define DELTA(x,y) ((y)-(x)+((y)<(x)?1193182/HZ:0))
#define GET_TIME(x) do { x = get_time_pit(); } while (0)
static unsigned int get_time_pit(void)
{
unsigned long flags;
unsigned int count;
spin_lock_irqsave(&i8253_lock, flags);
outb_p(0x00, 0x43);
count = inb_p(0x40);
count |= inb_p(0x40) << 8;
spin_unlock_irqrestore(&i8253_lock, flags);
return count;
}
#endif
/*
* gameport_measure_speed() measures the gameport i/o speed.
*/
static int gameport_measure_speed(struct gameport *gameport)
{
#if defined(__i386__)
unsigned int i, t, t1, t2, t3, tx;
unsigned long flags;
if (gameport_open(gameport, NULL, GAMEPORT_MODE_RAW))
return 0;
tx = 1 << 30;
for(i = 0; i < 50; i++) {
local_irq_save(flags);
GET_TIME(t1);
for (t = 0; t < 50; t++) gameport_read(gameport);
GET_TIME(t2);
GET_TIME(t3);
local_irq_restore(flags);
udelay(i * 10);
if ((t = DELTA(t2,t1) - DELTA(t3,t2)) < tx) tx = t;
}
gameport_close(gameport);
return 59659 / (tx < 1 ? 1 : tx);
#elif defined (__x86_64__)
unsigned int i, t;
unsigned long tx, t1, t2, flags;
if (gameport_open(gameport, NULL, GAMEPORT_MODE_RAW))
return 0;
tx = 1 << 30;
for(i = 0; i < 50; i++) {
local_irq_save(flags);
rdtscl(t1);
for (t = 0; t < 50; t++) gameport_read(gameport);
rdtscl(t2);
local_irq_restore(flags);
udelay(i * 10);
if (t2 - t1 < tx) tx = t2 - t1;
}
gameport_close(gameport);
return (cpu_data(raw_smp_processor_id()).loops_per_jiffy *
(unsigned long)HZ / (1000 / 50)) / (tx < 1 ? 1 : tx);
#else
unsigned int j, t = 0;
if (gameport_open(gameport, NULL, GAMEPORT_MODE_RAW))
return 0;
j = jiffies; while (j == jiffies);
j = jiffies; while (j == jiffies) { t++; gameport_read(gameport); }
gameport_close(gameport);
return t * HZ / 1000;
#endif
}
void gameport_start_polling(struct gameport *gameport)
{
spin_lock(&gameport->timer_lock);
if (!gameport->poll_cnt++) {
BUG_ON(!gameport->poll_handler);
BUG_ON(!gameport->poll_interval);
mod_timer(&gameport->poll_timer, jiffies + msecs_to_jiffies(gameport->poll_interval));
}
spin_unlock(&gameport->timer_lock);
}
void gameport_stop_polling(struct gameport *gameport)
{
spin_lock(&gameport->timer_lock);
if (!--gameport->poll_cnt)
del_timer(&gameport->poll_timer);
spin_unlock(&gameport->timer_lock);
}
static void gameport_run_poll_handler(unsigned long d)
{
struct gameport *gameport = (struct gameport *)d;
gameport->poll_handler(gameport);
if (gameport->poll_cnt)
mod_timer(&gameport->poll_timer, jiffies + msecs_to_jiffies(gameport->poll_interval));
}
/*
* Basic gameport -> driver core mappings
*/
static int gameport_bind_driver(struct gameport *gameport, struct gameport_driver *drv)
{
int error;
gameport->dev.driver = &drv->driver;
if (drv->connect(gameport, drv)) {
gameport->dev.driver = NULL;
return -ENODEV;
}
error = device_bind_driver(&gameport->dev);
if (error) {
printk(KERN_WARNING
"gameport: device_bind_driver() failed "
"for %s (%s) and %s, error: %d\n",
gameport->phys, gameport->name,
drv->description, error);
drv->disconnect(gameport);
gameport->dev.driver = NULL;
return error;
}
return 0;
}
static void gameport_find_driver(struct gameport *gameport)
{
int error;
error = device_attach(&gameport->dev);
if (error < 0)
printk(KERN_WARNING
"gameport: device_attach() failed for %s (%s), error: %d\n",
gameport->phys, gameport->name, error);
}
/*
* Gameport event processing.
*/
enum gameport_event_type {
GAMEPORT_REGISTER_PORT,
GAMEPORT_ATTACH_DRIVER,
};
struct gameport_event {
enum gameport_event_type type;
void *object;
struct module *owner;
struct list_head node;
};
static DEFINE_SPINLOCK(gameport_event_lock); /* protects gameport_event_list */
static LIST_HEAD(gameport_event_list);
static DECLARE_WAIT_QUEUE_HEAD(gameport_wait);
static struct task_struct *gameport_task;
static int gameport_queue_event(void *object, struct module *owner,
enum gameport_event_type event_type)
{
unsigned long flags;
struct gameport_event *event;
int retval = 0;
spin_lock_irqsave(&gameport_event_lock, flags);
/*
* Scan event list for the other events for the same gameport 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, &gameport_event_list, node) {
if (event->object == object) {
if (event->type == event_type)
goto out;
break;
}
}
event = kmalloc(sizeof(struct gameport_event), GFP_ATOMIC);
if (!event) {
printk(KERN_ERR
"gameport: Not enough memory to queue event %d\n",
event_type);
retval = -ENOMEM;
goto out;
}
if (!try_module_get(owner)) {
printk(KERN_WARNING
"gameport: 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, &gameport_event_list);
wake_up(&gameport_wait);
out:
spin_unlock_irqrestore(&gameport_event_lock, flags);
return retval;
}
static void gameport_free_event(struct gameport_event *event)
{
module_put(event->owner);
kfree(event);
}
static void gameport_remove_duplicate_events(struct gameport_event *event)
{
struct list_head *node, *next;
struct gameport_event *e;
unsigned long flags;
spin_lock_irqsave(&gameport_event_lock, flags);
list_for_each_safe(node, next, &gameport_event_list) {
e = list_entry(node, struct gameport_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);
gameport_free_event(e);
}
}
spin_unlock_irqrestore(&gameport_event_lock, flags);
}
static struct gameport_event *gameport_get_event(void)
{
struct gameport_event *event;
struct list_head *node;
unsigned long flags;
spin_lock_irqsave(&gameport_event_lock, flags);
if (list_empty(&gameport_event_list)) {
spin_unlock_irqrestore(&gameport_event_lock, flags);
return NULL;
}
node = gameport_event_list.next;
event = list_entry(node, struct gameport_event, node);
list_del_init(node);
spin_unlock_irqrestore(&gameport_event_lock, flags);
return event;
}
static void gameport_handle_event(void)
{
struct gameport_event *event;
mutex_lock(&gameport_mutex);
/*
* Note that we handle only one event here to give swsusp
* a chance to freeze kgameportd thread. Gameport events
* should be pretty rare so we are not concerned about
* taking performance hit.
*/
if ((event = gameport_get_event())) {
switch (event->type) {
case GAMEPORT_REGISTER_PORT:
gameport_add_port(event->object);
break;
case GAMEPORT_ATTACH_DRIVER:
gameport_attach_driver(event->object);
break;
default:
break;
}
gameport_remove_duplicate_events(event);
gameport_free_event(event);
}
mutex_unlock(&gameport_mutex);
}
/*
* Remove all events that have been submitted for a given object,
* be it a gameport port or a driver.
*/
static void gameport_remove_pending_events(void *object)
{
struct list_head *node, *next;
struct gameport_event *event;
unsigned long flags;
spin_lock_irqsave(&gameport_event_lock, flags);
list_for_each_safe(node, next, &gameport_event_list) {
event = list_entry(node, struct gameport_event, node);
if (event->object == object) {
list_del_init(node);
gameport_free_event(event);
}
}
spin_unlock_irqrestore(&gameport_event_lock, flags);
}
/*
* Destroy child gameport 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 gameport *gameport_get_pending_child(struct gameport *parent)
{
struct gameport_event *event;
struct gameport *gameport, *child = NULL;
unsigned long flags;
spin_lock_irqsave(&gameport_event_lock, flags);
list_for_each_entry(event, &gameport_event_list, node) {
if (event->type == GAMEPORT_REGISTER_PORT) {
gameport = event->object;
if (gameport->parent == parent) {
child = gameport;
break;
}
}
}
spin_unlock_irqrestore(&gameport_event_lock, flags);
return child;
}
static int gameport_thread(void *nothing)
{
set_freezable();
do {
gameport_handle_event();
wait_event_freezable(gameport_wait,
kthread_should_stop() || !list_empty(&gameport_event_list));
} while (!kthread_should_stop());
printk(KERN_DEBUG "gameport: kgameportd exiting\n");
return 0;
}
/*
* Gameport port operations
*/
static ssize_t gameport_show_description(struct device *dev, struct device_attribute *attr, char *buf)
{
struct gameport *gameport = to_gameport_port(dev);
return sprintf(buf, "%s\n", gameport->name);
}
static ssize_t gameport_rebind_driver(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
{
struct gameport *gameport = to_gameport_port(dev);
struct device_driver *drv;
int error;
error = mutex_lock_interruptible(&gameport_mutex);
if (error)
return error;
if (!strncmp(buf, "none", count)) {
gameport_disconnect_port(gameport);
} else if (!strncmp(buf, "reconnect", count)) {
gameport_reconnect_port(gameport);
} else if (!strncmp(buf, "rescan", count)) {
gameport_disconnect_port(gameport);
gameport_find_driver(gameport);
} else if ((drv = driver_find(buf, &gameport_bus)) != NULL) {
gameport_disconnect_port(gameport);
error = gameport_bind_driver(gameport, to_gameport_driver(drv));
put_driver(drv);
} else {
error = -EINVAL;
}
mutex_unlock(&gameport_mutex);
return error ? error : count;
}
static struct device_attribute gameport_device_attrs[] = {
__ATTR(description, S_IRUGO, gameport_show_description, NULL),
__ATTR(drvctl, S_IWUSR, NULL, gameport_rebind_driver),
__ATTR_NULL
};
static void gameport_release_port(struct device *dev)
{
struct gameport *gameport = to_gameport_port(dev);
kfree(gameport);
module_put(THIS_MODULE);
}
void gameport_set_phys(struct gameport *gameport, const char *fmt, ...)
{
va_list args;
va_start(args, fmt);
vsnprintf(gameport->phys, sizeof(gameport->phys), fmt, args);
va_end(args);
}
/*
* Prepare gameport port for registration.
*/
static void gameport_init_port(struct gameport *gameport)
{
static atomic_t gameport_no = ATOMIC_INIT(0);
__module_get(THIS_MODULE);
mutex_init(&gameport->drv_mutex);
device_initialize(&gameport->dev);
dev_set_name(&gameport->dev, "gameport%lu", (unsigned long)atomic_inc_return(&gameport_no) - 1);
gameport->dev.bus = &gameport_bus;
gameport->dev.release = gameport_release_port;
if (gameport->parent)
gameport->dev.parent = &gameport->parent->dev;
INIT_LIST_HEAD(&gameport->node);
spin_lock_init(&gameport->timer_lock);
init_timer(&gameport->poll_timer);
gameport->poll_timer.function = gameport_run_poll_handler;
gameport->poll_timer.data = (unsigned long)gameport;
}
/*
* Complete gameport port registration.
* Driver core will attempt to find appropriate driver for the port.
*/
static void gameport_add_port(struct gameport *gameport)
{
int error;
if (gameport->parent)
gameport->parent->child = gameport;
gameport->speed = gameport_measure_speed(gameport);
list_add_tail(&gameport->node, &gameport_list);
if (gameport->io)
printk(KERN_INFO "gameport: %s is %s, io %#x, speed %dkHz\n",
gameport->name, gameport->phys, gameport->io, gameport->speed);
else
printk(KERN_INFO "gameport: %s is %s, speed %dkHz\n",
gameport->name, gameport->phys, gameport->speed);
error = device_add(&gameport->dev);
if (error)
printk(KERN_ERR
"gameport: device_add() failed for %s (%s), error: %d\n",
gameport->phys, gameport->name, error);
else
gameport->registered = 1;
}
/*
* gameport_destroy_port() completes deregistration process and removes
* port from the system
*/
static void gameport_destroy_port(struct gameport *gameport)
{
struct gameport *child;
child = gameport_get_pending_child(gameport);
if (child) {
gameport_remove_pending_events(child);
put_device(&child->dev);
}
if (gameport->parent) {
gameport->parent->child = NULL;
gameport->parent = NULL;
}
if (gameport->registered) {
device_del(&gameport->dev);
gameport->registered = 0;
}
list_del_init(&gameport->node);
gameport_remove_pending_events(gameport);
put_device(&gameport->dev);
}
/*
* Reconnect gameport port and all its children (re-initialize attached devices)
*/
static void gameport_reconnect_port(struct gameport *gameport)
{
do {
if (!gameport->drv || !gameport->drv->reconnect || gameport->drv->reconnect(gameport)) {
gameport_disconnect_port(gameport);
gameport_find_driver(gameport);
/* Ok, old children are now gone, we are done */
break;
}
gameport = gameport->child;
} while (gameport);
}
/*
* gameport_disconnect_port() unbinds a port from its driver. As a side effect
* all child ports are unbound and destroyed.
*/
static void gameport_disconnect_port(struct gameport *gameport)
{
struct gameport *s, *parent;
if (gameport->child) {
/*
* Children ports should be disconnected and destroyed
* first, staring with the leaf one, since we don't want
* to do recursion
*/
for (s = gameport; s->child; s = s->child)
/* empty */;
do {
parent = s->parent;
device_release_driver(&s->dev);
gameport_destroy_port(s);
} while ((s = parent) != gameport);
}
/*
* Ok, no children left, now disconnect this port
*/
device_release_driver(&gameport->dev);
}
/*
* Submits register request to kgameportd for subsequent execution.
* Note that port registration is always asynchronous.
*/
void __gameport_register_port(struct gameport *gameport, struct module *owner)
{
gameport_init_port(gameport);
gameport_queue_event(gameport, owner, GAMEPORT_REGISTER_PORT);
}
/*
* Synchronously unregisters gameport port.
*/
void gameport_unregister_port(struct gameport *gameport)
{
mutex_lock(&gameport_mutex);
gameport_disconnect_port(gameport);
gameport_destroy_port(gameport);
mutex_unlock(&gameport_mutex);
}
/*
* Gameport driver operations
*/
static ssize_t gameport_driver_show_description(struct device_driver *drv, char *buf)
{
struct gameport_driver *driver = to_gameport_driver(drv);
return sprintf(buf, "%s\n", driver->description ? driver->description : "(none)");
}
static struct driver_attribute gameport_driver_attrs[] = {
__ATTR(description, S_IRUGO, gameport_driver_show_description, NULL),
__ATTR_NULL
};
static int gameport_driver_probe(struct device *dev)
{
struct gameport *gameport = to_gameport_port(dev);
struct gameport_driver *drv = to_gameport_driver(dev->driver);
drv->connect(gameport, drv);
return gameport->drv ? 0 : -ENODEV;
}
static int gameport_driver_remove(struct device *dev)
{
struct gameport *gameport = to_gameport_port(dev);
struct gameport_driver *drv = to_gameport_driver(dev->driver);
drv->disconnect(gameport);
return 0;
}
static void gameport_attach_driver(struct gameport_driver *drv)
{
int error;
error = driver_attach(&drv->driver);
if (error)
printk(KERN_ERR
"gameport: driver_attach() failed for %s, error: %d\n",
drv->driver.name, error);
}
int __gameport_register_driver(struct gameport_driver *drv, struct module *owner,
const char *mod_name)
{
int error;
drv->driver.bus = &gameport_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 kgameportd
*/
drv->ignore = 1;
error = driver_register(&drv->driver);
if (error) {
printk(KERN_ERR
"gameport: driver_register() failed for %s, error: %d\n",
drv->driver.name, error);
return error;
}
/*
* Reset ignore flag and let kgameportd bind the driver to free ports
*/
drv->ignore = 0;
error = gameport_queue_event(drv, NULL, GAMEPORT_ATTACH_DRIVER);
if (error) {
driver_unregister(&drv->driver);
return error;
}
return 0;
}
void gameport_unregister_driver(struct gameport_driver *drv)
{
struct gameport *gameport;
mutex_lock(&gameport_mutex);
drv->ignore = 1; /* so gameport_find_driver ignores it */
gameport_remove_pending_events(drv);
start_over:
list_for_each_entry(gameport, &gameport_list, node) {
if (gameport->drv == drv) {
gameport_disconnect_port(gameport);
gameport_find_driver(gameport);
/* we could've deleted some ports, restart */
goto start_over;
}
}
driver_unregister(&drv->driver);
mutex_unlock(&gameport_mutex);
}
static int gameport_bus_match(struct device *dev, struct device_driver *drv)
{
struct gameport_driver *gameport_drv = to_gameport_driver(drv);
return !gameport_drv->ignore;
}
static struct bus_type gameport_bus = {
.name = "gameport",
.dev_attrs = gameport_device_attrs,
.drv_attrs = gameport_driver_attrs,
.match = gameport_bus_match,
.probe = gameport_driver_probe,
.remove = gameport_driver_remove,
};
static void gameport_set_drv(struct gameport *gameport, struct gameport_driver *drv)
{
mutex_lock(&gameport->drv_mutex);
gameport->drv = drv;
mutex_unlock(&gameport->drv_mutex);
}
int gameport_open(struct gameport *gameport, struct gameport_driver *drv, int mode)
{
if (gameport->open) {
if (gameport->open(gameport, mode)) {
return -1;
}
} else {
if (mode != GAMEPORT_MODE_RAW)
return -1;
}
gameport_set_drv(gameport, drv);
return 0;
}
void gameport_close(struct gameport *gameport)
{
del_timer_sync(&gameport->poll_timer);
gameport->poll_handler = NULL;
gameport->poll_interval = 0;
gameport_set_drv(gameport, NULL);
if (gameport->close)
gameport->close(gameport);
}
static int __init gameport_init(void)
{
int error;
error = bus_register(&gameport_bus);
if (error) {
printk(KERN_ERR "gameport: failed to register gameport bus, error: %d\n", error);
return error;
}
gameport_task = kthread_run(gameport_thread, NULL, "kgameportd");
if (IS_ERR(gameport_task)) {
bus_unregister(&gameport_bus);
error = PTR_ERR(gameport_task);
printk(KERN_ERR "gameport: Failed to start kgameportd, error: %d\n", error);
return error;
}
return 0;
}
static void __exit gameport_exit(void)
{
bus_unregister(&gameport_bus);
kthread_stop(gameport_task);
}
subsys_initcall(gameport_init);
module_exit(gameport_exit);