diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/input/gameport/gameport.c | 856 |
1 files changed, 856 insertions, 0 deletions
diff --git a/drivers/input/gameport/gameport.c b/drivers/input/gameport/gameport.c new file mode 100644 index 000000000..61fa7e724 --- /dev/null +++ b/drivers/input/gameport/gameport.c @@ -0,0 +1,856 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Generic gameport layer + * + * Copyright (c) 1999-2002 Vojtech Pavlik + * Copyright (c) 2005 Dmitry Torokhov + */ + + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/stddef.h> +#include <linux/module.h> +#include <linux/ioport.h> +#include <linux/init.h> +#include <linux/gameport.h> +#include <linux/slab.h> +#include <linux/delay.h> +#include <linux/workqueue.h> +#include <linux/sched.h> /* HZ */ +#include <linux/mutex.h> +#include <linux/timekeeping.h> + +/*#include <asm/io.h>*/ + +MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>"); +MODULE_DESCRIPTION("Generic gameport layer"); +MODULE_LICENSE("GPL"); + +static bool use_ktime = true; +module_param(use_ktime, bool, 0400); +MODULE_PARM_DESC(use_ktime, "Use ktime for measuring I/O speed"); + +/* + * 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 <linux/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; + + raw_spin_lock_irqsave(&i8253_lock, flags); + outb_p(0x00, 0x43); + count = inb_p(0x40); + count |= inb_p(0x40) << 8; + raw_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) +{ + unsigned int i, t, tx; + u64 t1, t2, t3; + unsigned long flags; + + if (gameport_open(gameport, NULL, GAMEPORT_MODE_RAW)) + return 0; + + tx = ~0; + + for (i = 0; i < 50; i++) { + local_irq_save(flags); + t1 = ktime_get_ns(); + for (t = 0; t < 50; t++) + gameport_read(gameport); + t2 = ktime_get_ns(); + t3 = ktime_get_ns(); + local_irq_restore(flags); + udelay(i * 10); + t = (t2 - t1) - (t3 - t2); + if (t < tx) + tx = t; + } + + gameport_close(gameport); + t = 1000000 * 50; + if (tx) + t /= tx; + return t; +} + +static int old_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); + t1 = rdtsc(); + for (t = 0; t < 50; t++) gameport_read(gameport); + t2 = rdtsc(); + local_irq_restore(flags); + udelay(i * 10); + if (t2 - t1 < tx) tx = t2 - t1; + } + + gameport_close(gameport); + return (this_cpu_read(cpu_info.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); +} +EXPORT_SYMBOL(gameport_start_polling); + +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); +} +EXPORT_SYMBOL(gameport_stop_polling); + +static void gameport_run_poll_handler(struct timer_list *t) +{ + struct gameport *gameport = from_timer(gameport, t, poll_timer); + + 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) { + dev_warn(&gameport->dev, + "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) + dev_warn(&gameport->dev, + "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 struct gameport_event *gameport_get_event(void) +{ + struct gameport_event *event = NULL; + unsigned long flags; + + spin_lock_irqsave(&gameport_event_lock, flags); + + if (!list_empty(&gameport_event_list)) { + event = list_first_entry(&gameport_event_list, + struct gameport_event, node); + list_del_init(&event->node); + } + + spin_unlock_irqrestore(&gameport_event_lock, flags); + return event; +} + +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 gameport_event *e, *next; + unsigned long flags; + + spin_lock_irqsave(&gameport_event_lock, flags); + + list_for_each_entry_safe(e, next, &gameport_event_list, 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(&e->node); + gameport_free_event(e); + } + } + + spin_unlock_irqrestore(&gameport_event_lock, flags); +} + + +static void gameport_handle_events(struct work_struct *work) +{ + 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; + } + + gameport_remove_duplicate_events(event); + gameport_free_event(event); + } + + mutex_unlock(&gameport_mutex); +} + +static DECLARE_WORK(gameport_event_work, gameport_handle_events); + +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 preserve 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) { + 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, &gameport_event_list); + queue_work(system_long_wq, &gameport_event_work); + +out: + spin_unlock_irqrestore(&gameport_event_lock, flags); + return retval; +} + +/* + * 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 gameport_event *event, *next; + unsigned long flags; + + spin_lock_irqsave(&gameport_event_lock, flags); + + list_for_each_entry_safe(event, next, &gameport_event_list, node) { + if (event->object == object) { + list_del_init(&event->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; +} + +/* + * Gameport port operations + */ + +static ssize_t gameport_description_show(struct device *dev, struct device_attribute *attr, char *buf) +{ + struct gameport *gameport = to_gameport_port(dev); + + return sprintf(buf, "%s\n", gameport->name); +} +static DEVICE_ATTR(description, S_IRUGO, gameport_description_show, NULL); + +static ssize_t drvctl_store(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)); + } else { + error = -EINVAL; + } + + mutex_unlock(&gameport_mutex); + + return error ? error : count; +} +static DEVICE_ATTR_WO(drvctl); + +static struct attribute *gameport_device_attrs[] = { + &dev_attr_description.attr, + &dev_attr_drvctl.attr, + NULL, +}; +ATTRIBUTE_GROUPS(gameport_device); + +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); +} +EXPORT_SYMBOL(gameport_set_phys); + +/* + * Prepare gameport port for registration. + */ +static void gameport_init_port(struct gameport *gameport) +{ + static atomic_t gameport_no = ATOMIC_INIT(-1); + + __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)); + 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); + timer_setup(&gameport->poll_timer, gameport_run_poll_handler, 0); +} + +/* + * 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 = use_ktime ? + gameport_measure_speed(gameport) : + old_gameport_measure_speed(gameport); + + list_add_tail(&gameport->node, &gameport_list); + + if (gameport->io) + dev_info(&gameport->dev, "%s is %s, io %#x, speed %dkHz\n", + gameport->name, gameport->phys, gameport->io, gameport->speed); + else + dev_info(&gameport->dev, "%s is %s, speed %dkHz\n", + gameport->name, gameport->phys, gameport->speed); + + error = device_add(&gameport->dev); + if (error) + dev_err(&gameport->dev, + "device_add() failed for %s (%s), error: %d\n", + gameport->phys, gameport->name, error); +} + +/* + * 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 (device_is_registered(&gameport->dev)) + device_del(&gameport->dev); + + 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); +} +EXPORT_SYMBOL(__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); +} +EXPORT_SYMBOL(gameport_unregister_port); + + +/* + * Gameport driver operations + */ + +static ssize_t description_show(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 DRIVER_ATTR_RO(description); + +static struct attribute *gameport_driver_attrs[] = { + &driver_attr_description.attr, + NULL +}; +ATTRIBUTE_GROUPS(gameport_driver); + +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) + pr_err("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 = true; + + error = driver_register(&drv->driver); + if (error) { + pr_err("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 = false; + error = gameport_queue_event(drv, NULL, GAMEPORT_ATTACH_DRIVER); + if (error) { + driver_unregister(&drv->driver); + return error; + } + + return 0; +} +EXPORT_SYMBOL(__gameport_register_driver); + +void gameport_unregister_driver(struct gameport_driver *drv) +{ + struct gameport *gameport; + + mutex_lock(&gameport_mutex); + + drv->ignore = true; /* 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); +} +EXPORT_SYMBOL(gameport_unregister_driver); + +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_groups = gameport_device_groups, + .drv_groups = gameport_driver_groups, + .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; +} +EXPORT_SYMBOL(gameport_open); + +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); +} +EXPORT_SYMBOL(gameport_close); + +static int __init gameport_init(void) +{ + int error; + + error = bus_register(&gameport_bus); + if (error) { + pr_err("failed to register gameport bus, error: %d\n", error); + return error; + } + + + return 0; +} + +static void __exit gameport_exit(void) +{ + bus_unregister(&gameport_bus); + + /* + * There should not be any outstanding events but work may + * still be scheduled so simply cancel it. + */ + cancel_work_sync(&gameport_event_work); +} + +subsys_initcall(gameport_init); +module_exit(gameport_exit); |