2 * Event char devices, giving access to raw input device events.
4 * Copyright (c) 1999-2002 Vojtech Pavlik
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 as published by
8 * the Free Software Foundation.
11 #define EVDEV_MINOR_BASE 64
12 #define EVDEV_MINORS 32
13 #define EVDEV_BUFFER_SIZE 64
15 #include <linux/poll.h>
16 #include <linux/slab.h>
17 #include <linux/module.h>
18 #include <linux/init.h>
19 #include <linux/input.h>
20 #include <linux/major.h>
21 #include <linux/smp_lock.h>
22 #include <linux/device.h>
23 #include <linux/compat.h>
30 struct input_handle handle;
31 wait_queue_head_t wait;
32 struct evdev_client *grab;
33 struct list_head client_list;
37 struct input_event buffer[EVDEV_BUFFER_SIZE];
40 struct fasync_struct *fasync;
42 struct list_head node;
45 static struct evdev *evdev_table[EVDEV_MINORS];
47 static void evdev_event(struct input_handle *handle, unsigned int type, unsigned int code, int value)
49 struct evdev *evdev = handle->private;
50 struct evdev_client *client;
55 do_gettimeofday(&client->buffer[client->head].time);
56 client->buffer[client->head].type = type;
57 client->buffer[client->head].code = code;
58 client->buffer[client->head].value = value;
59 client->head = (client->head + 1) & (EVDEV_BUFFER_SIZE - 1);
61 kill_fasync(&client->fasync, SIGIO, POLL_IN);
63 list_for_each_entry(client, &evdev->client_list, node) {
65 do_gettimeofday(&client->buffer[client->head].time);
66 client->buffer[client->head].type = type;
67 client->buffer[client->head].code = code;
68 client->buffer[client->head].value = value;
69 client->head = (client->head + 1) & (EVDEV_BUFFER_SIZE - 1);
71 kill_fasync(&client->fasync, SIGIO, POLL_IN);
74 wake_up_interruptible(&evdev->wait);
77 static int evdev_fasync(int fd, struct file *file, int on)
79 struct evdev_client *client = file->private_data;
82 retval = fasync_helper(fd, file, on, &client->fasync);
84 return retval < 0 ? retval : 0;
87 static int evdev_flush(struct file *file, fl_owner_t id)
89 struct evdev_client *client = file->private_data;
90 struct evdev *evdev = client->evdev;
95 return input_flush_device(&evdev->handle, file);
98 static void evdev_free(struct evdev *evdev)
100 evdev_table[evdev->minor] = NULL;
104 static int evdev_release(struct inode *inode, struct file *file)
106 struct evdev_client *client = file->private_data;
107 struct evdev *evdev = client->evdev;
109 if (evdev->grab == client) {
110 input_release_device(&evdev->handle);
114 evdev_fasync(-1, file, 0);
115 list_del(&client->node);
118 if (!--evdev->open) {
120 input_close_device(&evdev->handle);
128 static int evdev_open(struct inode *inode, struct file *file)
130 struct evdev_client *client;
132 int i = iminor(inode) - EVDEV_MINOR_BASE;
135 if (i >= EVDEV_MINORS)
138 evdev = evdev_table[i];
140 if (!evdev || !evdev->exist)
143 client = kzalloc(sizeof(struct evdev_client), GFP_KERNEL);
147 client->evdev = evdev;
148 list_add_tail(&client->node, &evdev->client_list);
150 if (!evdev->open++ && evdev->exist) {
151 error = input_open_device(&evdev->handle);
153 list_del(&client->node);
159 file->private_data = client;
165 struct input_event_compat {
166 struct compat_timeval time;
172 /* Note to the author of this code: did it ever occur to
173 you why the ifdefs are needed? Think about it again. -AK */
175 # define COMPAT_TEST is_compat_task()
176 #elif defined(CONFIG_IA64)
177 # define COMPAT_TEST IS_IA32_PROCESS(task_pt_regs(current))
178 #elif defined(CONFIG_S390)
179 # define COMPAT_TEST test_thread_flag(TIF_31BIT)
180 #elif defined(CONFIG_MIPS)
181 # define COMPAT_TEST (current->thread.mflags & MF_32BIT_ADDR)
183 # define COMPAT_TEST test_thread_flag(TIF_32BIT)
186 static inline size_t evdev_event_size(void)
189 sizeof(struct input_event_compat) : sizeof(struct input_event);
192 static int evdev_event_from_user(const char __user *buffer, struct input_event *event)
195 struct input_event_compat compat_event;
197 if (copy_from_user(&compat_event, buffer, sizeof(struct input_event_compat)))
200 event->time.tv_sec = compat_event.time.tv_sec;
201 event->time.tv_usec = compat_event.time.tv_usec;
202 event->type = compat_event.type;
203 event->code = compat_event.code;
204 event->value = compat_event.value;
207 if (copy_from_user(event, buffer, sizeof(struct input_event)))
214 static int evdev_event_to_user(char __user *buffer, const struct input_event *event)
217 struct input_event_compat compat_event;
219 compat_event.time.tv_sec = event->time.tv_sec;
220 compat_event.time.tv_usec = event->time.tv_usec;
221 compat_event.type = event->type;
222 compat_event.code = event->code;
223 compat_event.value = event->value;
225 if (copy_to_user(buffer, &compat_event, sizeof(struct input_event_compat)))
229 if (copy_to_user(buffer, event, sizeof(struct input_event)))
238 static inline size_t evdev_event_size(void)
240 return sizeof(struct input_event);
243 static int evdev_event_from_user(const char __user *buffer, struct input_event *event)
245 if (copy_from_user(event, buffer, sizeof(struct input_event)))
251 static int evdev_event_to_user(char __user *buffer, const struct input_event *event)
253 if (copy_to_user(buffer, event, sizeof(struct input_event)))
259 #endif /* CONFIG_COMPAT */
261 static ssize_t evdev_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
263 struct evdev_client *client = file->private_data;
264 struct evdev *evdev = client->evdev;
265 struct input_event event;
271 while (retval < count) {
273 if (evdev_event_from_user(buffer + retval, &event))
275 input_inject_event(&evdev->handle, event.type, event.code, event.value);
276 retval += evdev_event_size();
282 static ssize_t evdev_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos)
284 struct evdev_client *client = file->private_data;
285 struct evdev *evdev = client->evdev;
288 if (count < evdev_event_size())
291 if (client->head == client->tail && evdev->exist && (file->f_flags & O_NONBLOCK))
294 retval = wait_event_interruptible(evdev->wait,
295 client->head != client->tail || !evdev->exist);
302 while (client->head != client->tail && retval + evdev_event_size() <= count) {
304 struct input_event *event = (struct input_event *) client->buffer + client->tail;
306 if (evdev_event_to_user(buffer + retval, event))
309 client->tail = (client->tail + 1) & (EVDEV_BUFFER_SIZE - 1);
310 retval += evdev_event_size();
316 /* No kernel lock - fine */
317 static unsigned int evdev_poll(struct file *file, poll_table *wait)
319 struct evdev_client *client = file->private_data;
320 struct evdev *evdev = client->evdev;
322 poll_wait(file, &evdev->wait, wait);
323 return ((client->head == client->tail) ? 0 : (POLLIN | POLLRDNORM)) |
324 (evdev->exist ? 0 : (POLLHUP | POLLERR));
329 #define BITS_PER_LONG_COMPAT (sizeof(compat_long_t) * 8)
330 #define NBITS_COMPAT(x) ((((x) - 1) / BITS_PER_LONG_COMPAT) + 1)
333 static int bits_to_user(unsigned long *bits, unsigned int maxbit,
334 unsigned int maxlen, void __user *p, int compat)
339 len = NBITS_COMPAT(maxbit) * sizeof(compat_long_t);
343 for (i = 0; i < len / sizeof(compat_long_t); i++)
344 if (copy_to_user((compat_long_t __user *) p + i,
345 (compat_long_t *) bits +
346 i + 1 - ((i % 2) << 1),
347 sizeof(compat_long_t)))
350 len = NBITS(maxbit) * sizeof(long);
354 if (copy_to_user(p, bits, len))
361 static int bits_to_user(unsigned long *bits, unsigned int maxbit,
362 unsigned int maxlen, void __user *p, int compat)
365 NBITS_COMPAT(maxbit) * sizeof(compat_long_t) :
366 NBITS(maxbit) * sizeof(long);
371 return copy_to_user(p, bits, len) ? -EFAULT : len;
373 #endif /* __BIG_ENDIAN */
377 static int bits_to_user(unsigned long *bits, unsigned int maxbit,
378 unsigned int maxlen, void __user *p, int compat)
380 int len = NBITS(maxbit) * sizeof(long);
385 return copy_to_user(p, bits, len) ? -EFAULT : len;
388 #endif /* CONFIG_COMPAT */
390 static int str_to_user(const char *str, unsigned int maxlen, void __user *p)
397 len = strlen(str) + 1;
401 return copy_to_user(p, str, len) ? -EFAULT : len;
404 static long evdev_ioctl_handler(struct file *file, unsigned int cmd,
405 void __user *p, int compat_mode)
407 struct evdev_client *client = file->private_data;
408 struct evdev *evdev = client->evdev;
409 struct input_dev *dev = evdev->handle.dev;
410 struct input_absinfo abs;
411 struct ff_effect effect;
412 int __user *ip = (int __user *)p;
422 return put_user(EV_VERSION, ip);
425 if (copy_to_user(p, &dev->id, sizeof(struct input_id)))
430 if (!test_bit(EV_REP, dev->evbit))
432 if (put_user(dev->rep[REP_DELAY], ip))
434 if (put_user(dev->rep[REP_PERIOD], ip + 1))
439 if (!test_bit(EV_REP, dev->evbit))
443 if (get_user(v, ip + 1))
446 input_inject_event(&evdev->handle, EV_REP, REP_DELAY, u);
447 input_inject_event(&evdev->handle, EV_REP, REP_PERIOD, v);
455 error = dev->getkeycode(dev, t, &v);
459 if (put_user(v, ip + 1))
465 if (get_user(t, ip) || get_user(v, ip + 1))
468 return dev->setkeycode(dev, t, v);
471 if (copy_from_user(&effect, p, sizeof(effect)))
474 error = input_ff_upload(dev, &effect, file);
476 if (put_user(effect.id, &(((struct ff_effect __user *)p)->id)))
482 return input_ff_erase(dev, (int)(unsigned long) p, file);
485 i = test_bit(EV_FF, dev->evbit) ? dev->ff->max_effects : 0;
494 if (input_grab_device(&evdev->handle))
496 evdev->grab = client;
499 if (evdev->grab != client)
501 input_release_device(&evdev->handle);
508 if (_IOC_TYPE(cmd) != 'E')
511 if (_IOC_DIR(cmd) == _IOC_READ) {
513 if ((_IOC_NR(cmd) & ~EV_MAX) == _IOC_NR(EVIOCGBIT(0,0))) {
518 switch (_IOC_NR(cmd) & EV_MAX) {
519 case 0: bits = dev->evbit; len = EV_MAX; break;
520 case EV_KEY: bits = dev->keybit; len = KEY_MAX; break;
521 case EV_REL: bits = dev->relbit; len = REL_MAX; break;
522 case EV_ABS: bits = dev->absbit; len = ABS_MAX; break;
523 case EV_MSC: bits = dev->mscbit; len = MSC_MAX; break;
524 case EV_LED: bits = dev->ledbit; len = LED_MAX; break;
525 case EV_SND: bits = dev->sndbit; len = SND_MAX; break;
526 case EV_FF: bits = dev->ffbit; len = FF_MAX; break;
527 case EV_SW: bits = dev->swbit; len = SW_MAX; break;
528 default: return -EINVAL;
530 return bits_to_user(bits, len, _IOC_SIZE(cmd), p, compat_mode);
533 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGKEY(0)))
534 return bits_to_user(dev->key, KEY_MAX, _IOC_SIZE(cmd),
537 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGLED(0)))
538 return bits_to_user(dev->led, LED_MAX, _IOC_SIZE(cmd),
541 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSND(0)))
542 return bits_to_user(dev->snd, SND_MAX, _IOC_SIZE(cmd),
545 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSW(0)))
546 return bits_to_user(dev->sw, SW_MAX, _IOC_SIZE(cmd),
549 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGNAME(0)))
550 return str_to_user(dev->name, _IOC_SIZE(cmd), p);
552 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGPHYS(0)))
553 return str_to_user(dev->phys, _IOC_SIZE(cmd), p);
555 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGUNIQ(0)))
556 return str_to_user(dev->uniq, _IOC_SIZE(cmd), p);
558 if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCGABS(0))) {
560 t = _IOC_NR(cmd) & ABS_MAX;
562 abs.value = dev->abs[t];
563 abs.minimum = dev->absmin[t];
564 abs.maximum = dev->absmax[t];
565 abs.fuzz = dev->absfuzz[t];
566 abs.flat = dev->absflat[t];
568 if (copy_to_user(p, &abs, sizeof(struct input_absinfo)))
576 if (_IOC_DIR(cmd) == _IOC_WRITE) {
578 if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCSABS(0))) {
580 t = _IOC_NR(cmd) & ABS_MAX;
582 if (copy_from_user(&abs, p, sizeof(struct input_absinfo)))
585 dev->abs[t] = abs.value;
586 dev->absmin[t] = abs.minimum;
587 dev->absmax[t] = abs.maximum;
588 dev->absfuzz[t] = abs.fuzz;
589 dev->absflat[t] = abs.flat;
598 static long evdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
600 return evdev_ioctl_handler(file, cmd, (void __user *)arg, 0);
604 static long evdev_ioctl_compat(struct file *file, unsigned int cmd, unsigned long arg)
606 return evdev_ioctl_handler(file, cmd, compat_ptr(arg), 1);
610 static const struct file_operations evdev_fops = {
611 .owner = THIS_MODULE,
613 .write = evdev_write,
616 .release = evdev_release,
617 .unlocked_ioctl = evdev_ioctl,
619 .compat_ioctl = evdev_ioctl_compat,
621 .fasync = evdev_fasync,
625 static int evdev_connect(struct input_handler *handler, struct input_dev *dev,
626 const struct input_device_id *id)
629 struct class_device *cdev;
634 for (minor = 0; minor < EVDEV_MINORS && evdev_table[minor]; minor++);
635 if (minor == EVDEV_MINORS) {
636 printk(KERN_ERR "evdev: no more free evdev devices\n");
640 evdev = kzalloc(sizeof(struct evdev), GFP_KERNEL);
644 INIT_LIST_HEAD(&evdev->client_list);
645 init_waitqueue_head(&evdev->wait);
648 evdev->minor = minor;
649 evdev->handle.dev = dev;
650 evdev->handle.name = evdev->name;
651 evdev->handle.handler = handler;
652 evdev->handle.private = evdev;
653 sprintf(evdev->name, "event%d", minor);
655 evdev_table[minor] = evdev;
657 devt = MKDEV(INPUT_MAJOR, EVDEV_MINOR_BASE + minor),
659 cdev = class_device_create(&input_class, &dev->cdev, devt,
660 dev->cdev.dev, evdev->name);
662 error = PTR_ERR(cdev);
666 /* temporary symlink to keep userspace happy */
667 error = sysfs_create_link(&input_class.subsys.kobj,
668 &cdev->kobj, evdev->name);
670 goto err_cdev_destroy;
672 error = input_register_handle(&evdev->handle);
674 goto err_remove_link;
679 sysfs_remove_link(&input_class.subsys.kobj, evdev->name);
681 class_device_destroy(&input_class, devt);
684 evdev_table[minor] = NULL;
688 static void evdev_disconnect(struct input_handle *handle)
690 struct evdev *evdev = handle->private;
691 struct evdev_client *client;
693 input_unregister_handle(handle);
695 sysfs_remove_link(&input_class.subsys.kobj, evdev->name);
696 class_device_destroy(&input_class,
697 MKDEV(INPUT_MAJOR, EVDEV_MINOR_BASE + evdev->minor));
701 input_flush_device(handle, NULL);
702 input_close_device(handle);
703 wake_up_interruptible(&evdev->wait);
704 list_for_each_entry(client, &evdev->client_list, node)
705 kill_fasync(&client->fasync, SIGIO, POLL_HUP);
710 static const struct input_device_id evdev_ids[] = {
711 { .driver_info = 1 }, /* Matches all devices */
712 { }, /* Terminating zero entry */
715 MODULE_DEVICE_TABLE(input, evdev_ids);
717 static struct input_handler evdev_handler = {
718 .event = evdev_event,
719 .connect = evdev_connect,
720 .disconnect = evdev_disconnect,
722 .minor = EVDEV_MINOR_BASE,
724 .id_table = evdev_ids,
727 static int __init evdev_init(void)
729 return input_register_handler(&evdev_handler);
732 static void __exit evdev_exit(void)
734 input_unregister_handler(&evdev_handler);
737 module_init(evdev_init);
738 module_exit(evdev_exit);
740 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
741 MODULE_DESCRIPTION("Input driver event char devices");
742 MODULE_LICENSE("GPL");