Input: reduce raciness when input handlers disconnect
[linux-2.6.git] / drivers / input / joydev.c
1 /*
2  * Joystick device driver for the input driver suite.
3  *
4  * Copyright (c) 1999-2002 Vojtech Pavlik
5  * Copyright (c) 1999 Colin Van Dyke
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11  */
12
13 #include <asm/io.h>
14 #include <asm/system.h>
15 #include <linux/delay.h>
16 #include <linux/errno.h>
17 #include <linux/joystick.h>
18 #include <linux/input.h>
19 #include <linux/kernel.h>
20 #include <linux/major.h>
21 #include <linux/slab.h>
22 #include <linux/mm.h>
23 #include <linux/miscdevice.h>
24 #include <linux/module.h>
25 #include <linux/poll.h>
26 #include <linux/init.h>
27 #include <linux/smp_lock.h>
28 #include <linux/device.h>
29
30 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
31 MODULE_DESCRIPTION("Joystick device interfaces");
32 MODULE_SUPPORTED_DEVICE("input/js");
33 MODULE_LICENSE("GPL");
34
35 #define JOYDEV_MINOR_BASE       0
36 #define JOYDEV_MINORS           16
37 #define JOYDEV_BUFFER_SIZE      64
38
39 struct joydev {
40         int exist;
41         int open;
42         int minor;
43         char name[16];
44         struct input_handle handle;
45         wait_queue_head_t wait;
46         struct list_head client_list;
47         struct js_corr corr[ABS_MAX + 1];
48         struct JS_DATA_SAVE_TYPE glue;
49         int nabs;
50         int nkey;
51         __u16 keymap[KEY_MAX - BTN_MISC + 1];
52         __u16 keypam[KEY_MAX - BTN_MISC + 1];
53         __u8 absmap[ABS_MAX + 1];
54         __u8 abspam[ABS_MAX + 1];
55         __s16 abs[ABS_MAX + 1];
56 };
57
58 struct joydev_client {
59         struct js_event buffer[JOYDEV_BUFFER_SIZE];
60         int head;
61         int tail;
62         int startup;
63         struct fasync_struct *fasync;
64         struct joydev *joydev;
65         struct list_head node;
66 };
67
68 static struct joydev *joydev_table[JOYDEV_MINORS];
69
70 static int joydev_correct(int value, struct js_corr *corr)
71 {
72         switch (corr->type) {
73                 case JS_CORR_NONE:
74                         break;
75                 case JS_CORR_BROKEN:
76                         value = value > corr->coef[0] ? (value < corr->coef[1] ? 0 :
77                                 ((corr->coef[3] * (value - corr->coef[1])) >> 14)) :
78                                 ((corr->coef[2] * (value - corr->coef[0])) >> 14);
79                         break;
80                 default:
81                         return 0;
82         }
83
84         return value < -32767 ? -32767 : (value > 32767 ? 32767 : value);
85 }
86
87 static void joydev_event(struct input_handle *handle, unsigned int type, unsigned int code, int value)
88 {
89         struct joydev *joydev = handle->private;
90         struct joydev_client *client;
91         struct js_event event;
92
93         switch (type) {
94
95                 case EV_KEY:
96                         if (code < BTN_MISC || value == 2)
97                                 return;
98                         event.type = JS_EVENT_BUTTON;
99                         event.number = joydev->keymap[code - BTN_MISC];
100                         event.value = value;
101                         break;
102
103                 case EV_ABS:
104                         event.type = JS_EVENT_AXIS;
105                         event.number = joydev->absmap[code];
106                         event.value = joydev_correct(value, joydev->corr + event.number);
107                         if (event.value == joydev->abs[event.number])
108                                 return;
109                         joydev->abs[event.number] = event.value;
110                         break;
111
112                 default:
113                         return;
114         }
115
116         event.time = jiffies_to_msecs(jiffies);
117
118         list_for_each_entry(client, &joydev->client_list, node) {
119
120                 memcpy(client->buffer + client->head, &event, sizeof(struct js_event));
121
122                 if (client->startup == joydev->nabs + joydev->nkey)
123                         if (client->tail == (client->head = (client->head + 1) & (JOYDEV_BUFFER_SIZE - 1)))
124                                 client->startup = 0;
125
126                 kill_fasync(&client->fasync, SIGIO, POLL_IN);
127         }
128
129         wake_up_interruptible(&joydev->wait);
130 }
131
132 static int joydev_fasync(int fd, struct file *file, int on)
133 {
134         int retval;
135         struct joydev_client *client = file->private_data;
136
137         retval = fasync_helper(fd, file, on, &client->fasync);
138
139         return retval < 0 ? retval : 0;
140 }
141
142 static void joydev_free(struct joydev *joydev)
143 {
144         joydev_table[joydev->minor] = NULL;
145         kfree(joydev);
146 }
147
148 static int joydev_release(struct inode *inode, struct file *file)
149 {
150         struct joydev_client *client = file->private_data;
151         struct joydev *joydev = client->joydev;
152
153         joydev_fasync(-1, file, 0);
154
155         list_del(&client->node);
156         kfree(client);
157
158         if (!--joydev->open) {
159                 if (joydev->exist)
160                         input_close_device(&joydev->handle);
161                 else
162                         joydev_free(joydev);
163         }
164
165         return 0;
166 }
167
168 static int joydev_open(struct inode *inode, struct file *file)
169 {
170         struct joydev_client *client;
171         struct joydev *joydev;
172         int i = iminor(inode) - JOYDEV_MINOR_BASE;
173         int error;
174
175         if (i >= JOYDEV_MINORS)
176                 return -ENODEV;
177
178         joydev = joydev_table[i];
179         if (!joydev || !joydev->exist)
180                 return -ENODEV;
181
182         client = kzalloc(sizeof(struct joydev_client), GFP_KERNEL);
183         if (!client)
184                 return -ENOMEM;
185
186         client->joydev = joydev;
187         list_add_tail(&client->node, &joydev->client_list);
188
189         if (!joydev->open++ && joydev->exist) {
190                 error = input_open_device(&joydev->handle);
191                 if (error) {
192                         list_del(&client->node);
193                         kfree(client);
194                         return error;
195                 }
196         }
197
198         file->private_data = client;
199         return 0;
200 }
201
202 static ssize_t joydev_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
203 {
204         return -EINVAL;
205 }
206
207 static ssize_t joydev_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
208 {
209         struct joydev_client *client = file->private_data;
210         struct joydev *joydev = client->joydev;
211         struct input_dev *input = joydev->handle.dev;
212         int retval = 0;
213
214         if (!joydev->exist)
215                 return -ENODEV;
216
217         if (count < sizeof(struct js_event))
218                 return -EINVAL;
219
220         if (count == sizeof(struct JS_DATA_TYPE)) {
221
222                 struct JS_DATA_TYPE data;
223                 int i;
224
225                 for (data.buttons = i = 0; i < 32 && i < joydev->nkey; i++)
226                         data.buttons |= test_bit(joydev->keypam[i], input->key) ? (1 << i) : 0;
227                 data.x = (joydev->abs[0] / 256 + 128) >> joydev->glue.JS_CORR.x;
228                 data.y = (joydev->abs[1] / 256 + 128) >> joydev->glue.JS_CORR.y;
229
230                 if (copy_to_user(buf, &data, sizeof(struct JS_DATA_TYPE)))
231                         return -EFAULT;
232
233                 client->startup = 0;
234                 client->tail = client->head;
235
236                 return sizeof(struct JS_DATA_TYPE);
237         }
238
239         if (client->startup == joydev->nabs + joydev->nkey &&
240             client->head == client->tail && (file->f_flags & O_NONBLOCK))
241                 return -EAGAIN;
242
243         retval = wait_event_interruptible(joydev->wait,
244                                           !joydev->exist ||
245                                           client->startup < joydev->nabs + joydev->nkey ||
246                                           client->head != client->tail);
247         if (retval)
248                 return retval;
249
250         if (!joydev->exist)
251                 return -ENODEV;
252
253         while (client->startup < joydev->nabs + joydev->nkey && retval + sizeof(struct js_event) <= count) {
254
255                 struct js_event event;
256
257                 event.time = jiffies_to_msecs(jiffies);
258
259                 if (client->startup < joydev->nkey) {
260                         event.type = JS_EVENT_BUTTON | JS_EVENT_INIT;
261                         event.number = client->startup;
262                         event.value = !!test_bit(joydev->keypam[event.number], input->key);
263                 } else {
264                         event.type = JS_EVENT_AXIS | JS_EVENT_INIT;
265                         event.number = client->startup - joydev->nkey;
266                         event.value = joydev->abs[event.number];
267                 }
268
269                 if (copy_to_user(buf + retval, &event, sizeof(struct js_event)))
270                         return -EFAULT;
271
272                 client->startup++;
273                 retval += sizeof(struct js_event);
274         }
275
276         while (client->head != client->tail && retval + sizeof(struct js_event) <= count) {
277
278                 if (copy_to_user(buf + retval, client->buffer + client->tail, sizeof(struct js_event)))
279                         return -EFAULT;
280
281                 client->tail = (client->tail + 1) & (JOYDEV_BUFFER_SIZE - 1);
282                 retval += sizeof(struct js_event);
283         }
284
285         return retval;
286 }
287
288 /* No kernel lock - fine */
289 static unsigned int joydev_poll(struct file *file, poll_table *wait)
290 {
291         struct joydev_client *client = file->private_data;
292         struct joydev *joydev = client->joydev;
293
294         poll_wait(file, &joydev->wait, wait);
295         return ((client->head != client->tail || client->startup < joydev->nabs + joydev->nkey) ?
296                 (POLLIN | POLLRDNORM) : 0) | (joydev->exist ? 0 : (POLLHUP | POLLERR));
297 }
298
299 static int joydev_ioctl_common(struct joydev *joydev, unsigned int cmd, void __user *argp)
300 {
301         struct input_dev *dev = joydev->handle.dev;
302         int i, j;
303
304         switch (cmd) {
305
306                 case JS_SET_CAL:
307                         return copy_from_user(&joydev->glue.JS_CORR, argp,
308                                 sizeof(joydev->glue.JS_CORR)) ? -EFAULT : 0;
309
310                 case JS_GET_CAL:
311                         return copy_to_user(argp, &joydev->glue.JS_CORR,
312                                 sizeof(joydev->glue.JS_CORR)) ? -EFAULT : 0;
313
314                 case JS_SET_TIMEOUT:
315                         return get_user(joydev->glue.JS_TIMEOUT, (s32 __user *) argp);
316
317                 case JS_GET_TIMEOUT:
318                         return put_user(joydev->glue.JS_TIMEOUT, (s32 __user *) argp);
319
320                 case JSIOCGVERSION:
321                         return put_user(JS_VERSION, (__u32 __user *) argp);
322
323                 case JSIOCGAXES:
324                         return put_user(joydev->nabs, (__u8 __user *) argp);
325
326                 case JSIOCGBUTTONS:
327                         return put_user(joydev->nkey, (__u8 __user *) argp);
328
329                 case JSIOCSCORR:
330                         if (copy_from_user(joydev->corr, argp,
331                                       sizeof(joydev->corr[0]) * joydev->nabs))
332                             return -EFAULT;
333                         for (i = 0; i < joydev->nabs; i++) {
334                                 j = joydev->abspam[i];
335                                 joydev->abs[i] = joydev_correct(dev->abs[j], joydev->corr + i);
336                         }
337                         return 0;
338
339                 case JSIOCGCORR:
340                         return copy_to_user(argp, joydev->corr,
341                                                 sizeof(joydev->corr[0]) * joydev->nabs) ? -EFAULT : 0;
342
343                 case JSIOCSAXMAP:
344                         if (copy_from_user(joydev->abspam, argp, sizeof(__u8) * (ABS_MAX + 1)))
345                                 return -EFAULT;
346                         for (i = 0; i < joydev->nabs; i++) {
347                                 if (joydev->abspam[i] > ABS_MAX)
348                                         return -EINVAL;
349                                 joydev->absmap[joydev->abspam[i]] = i;
350                         }
351                         return 0;
352
353                 case JSIOCGAXMAP:
354                         return copy_to_user(argp, joydev->abspam,
355                                                 sizeof(__u8) * (ABS_MAX + 1)) ? -EFAULT : 0;
356
357                 case JSIOCSBTNMAP:
358                         if (copy_from_user(joydev->keypam, argp, sizeof(__u16) * (KEY_MAX - BTN_MISC + 1)))
359                                 return -EFAULT;
360                         for (i = 0; i < joydev->nkey; i++) {
361                                 if (joydev->keypam[i] > KEY_MAX || joydev->keypam[i] < BTN_MISC)
362                                         return -EINVAL;
363                                 joydev->keymap[joydev->keypam[i] - BTN_MISC] = i;
364                         }
365                         return 0;
366
367                 case JSIOCGBTNMAP:
368                         return copy_to_user(argp, joydev->keypam,
369                                                 sizeof(__u16) * (KEY_MAX - BTN_MISC + 1)) ? -EFAULT : 0;
370
371                 default:
372                         if ((cmd & ~(_IOC_SIZEMASK << _IOC_SIZESHIFT)) == JSIOCGNAME(0)) {
373                                 int len;
374                                 if (!dev->name)
375                                         return 0;
376                                 len = strlen(dev->name) + 1;
377                                 if (len > _IOC_SIZE(cmd))
378                                         len = _IOC_SIZE(cmd);
379                                 if (copy_to_user(argp, dev->name, len))
380                                         return -EFAULT;
381                                 return len;
382                         }
383         }
384         return -EINVAL;
385 }
386
387 #ifdef CONFIG_COMPAT
388 static long joydev_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
389 {
390         struct joydev_client *client = file->private_data;
391         struct joydev *joydev = client->joydev;
392         void __user *argp = (void __user *)arg;
393         s32 tmp32;
394         struct JS_DATA_SAVE_TYPE_32 ds32;
395         int err;
396
397         if (!joydev->exist)
398                 return -ENODEV;
399
400         switch(cmd) {
401         case JS_SET_TIMELIMIT:
402                 err = get_user(tmp32, (s32 __user *) arg);
403                 if (err == 0)
404                         joydev->glue.JS_TIMELIMIT = tmp32;
405                 break;
406         case JS_GET_TIMELIMIT:
407                 tmp32 = joydev->glue.JS_TIMELIMIT;
408                 err = put_user(tmp32, (s32 __user *) arg);
409                 break;
410
411         case JS_SET_ALL:
412                 err = copy_from_user(&ds32, argp,
413                                      sizeof(ds32)) ? -EFAULT : 0;
414                 if (err == 0) {
415                         joydev->glue.JS_TIMEOUT    = ds32.JS_TIMEOUT;
416                         joydev->glue.BUSY          = ds32.BUSY;
417                         joydev->glue.JS_EXPIRETIME = ds32.JS_EXPIRETIME;
418                         joydev->glue.JS_TIMELIMIT  = ds32.JS_TIMELIMIT;
419                         joydev->glue.JS_SAVE       = ds32.JS_SAVE;
420                         joydev->glue.JS_CORR       = ds32.JS_CORR;
421                 }
422                 break;
423
424         case JS_GET_ALL:
425                 ds32.JS_TIMEOUT    = joydev->glue.JS_TIMEOUT;
426                 ds32.BUSY          = joydev->glue.BUSY;
427                 ds32.JS_EXPIRETIME = joydev->glue.JS_EXPIRETIME;
428                 ds32.JS_TIMELIMIT  = joydev->glue.JS_TIMELIMIT;
429                 ds32.JS_SAVE       = joydev->glue.JS_SAVE;
430                 ds32.JS_CORR       = joydev->glue.JS_CORR;
431
432                 err = copy_to_user(argp, &ds32, sizeof(ds32)) ? -EFAULT : 0;
433                 break;
434
435         default:
436                 err = joydev_ioctl_common(joydev, cmd, argp);
437         }
438         return err;
439 }
440 #endif /* CONFIG_COMPAT */
441
442 static int joydev_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
443 {
444         struct joydev_client *client = file->private_data;
445         struct joydev *joydev = client->joydev;
446         void __user *argp = (void __user *)arg;
447
448         if (!joydev->exist)
449                 return -ENODEV;
450
451         switch(cmd) {
452                 case JS_SET_TIMELIMIT:
453                         return get_user(joydev->glue.JS_TIMELIMIT, (long __user *) arg);
454                 case JS_GET_TIMELIMIT:
455                         return put_user(joydev->glue.JS_TIMELIMIT, (long __user *) arg);
456                 case JS_SET_ALL:
457                         return copy_from_user(&joydev->glue, argp,
458                                                 sizeof(joydev->glue)) ? -EFAULT : 0;
459                 case JS_GET_ALL:
460                         return copy_to_user(argp, &joydev->glue,
461                                                 sizeof(joydev->glue)) ? -EFAULT : 0;
462                 default:
463                         return joydev_ioctl_common(joydev, cmd, argp);
464         }
465 }
466
467 static const struct file_operations joydev_fops = {
468         .owner =        THIS_MODULE,
469         .read =         joydev_read,
470         .write =        joydev_write,
471         .poll =         joydev_poll,
472         .open =         joydev_open,
473         .release =      joydev_release,
474         .ioctl =        joydev_ioctl,
475 #ifdef CONFIG_COMPAT
476         .compat_ioctl = joydev_compat_ioctl,
477 #endif
478         .fasync =       joydev_fasync,
479 };
480
481 static int joydev_connect(struct input_handler *handler, struct input_dev *dev,
482                           const struct input_device_id *id)
483 {
484         struct joydev *joydev;
485         struct class_device *cdev;
486         dev_t devt;
487         int i, j, t, minor;
488         int error;
489
490         for (minor = 0; minor < JOYDEV_MINORS && joydev_table[minor]; minor++);
491         if (minor == JOYDEV_MINORS) {
492                 printk(KERN_ERR "joydev: no more free joydev devices\n");
493                 return -ENFILE;
494         }
495
496         joydev = kzalloc(sizeof(struct joydev), GFP_KERNEL);
497         if (!joydev)
498                 return -ENOMEM;
499
500         INIT_LIST_HEAD(&joydev->client_list);
501         init_waitqueue_head(&joydev->wait);
502
503         joydev->minor = minor;
504         joydev->exist = 1;
505         joydev->handle.dev = dev;
506         joydev->handle.name = joydev->name;
507         joydev->handle.handler = handler;
508         joydev->handle.private = joydev;
509         sprintf(joydev->name, "js%d", minor);
510
511         for (i = 0; i < ABS_MAX + 1; i++)
512                 if (test_bit(i, dev->absbit)) {
513                         joydev->absmap[i] = joydev->nabs;
514                         joydev->abspam[joydev->nabs] = i;
515                         joydev->nabs++;
516                 }
517
518         for (i = BTN_JOYSTICK - BTN_MISC; i < KEY_MAX - BTN_MISC + 1; i++)
519                 if (test_bit(i + BTN_MISC, dev->keybit)) {
520                         joydev->keymap[i] = joydev->nkey;
521                         joydev->keypam[joydev->nkey] = i + BTN_MISC;
522                         joydev->nkey++;
523                 }
524
525         for (i = 0; i < BTN_JOYSTICK - BTN_MISC; i++)
526                 if (test_bit(i + BTN_MISC, dev->keybit)) {
527                         joydev->keymap[i] = joydev->nkey;
528                         joydev->keypam[joydev->nkey] = i + BTN_MISC;
529                         joydev->nkey++;
530                 }
531
532         for (i = 0; i < joydev->nabs; i++) {
533                 j = joydev->abspam[i];
534                 if (dev->absmax[j] == dev->absmin[j]) {
535                         joydev->corr[i].type = JS_CORR_NONE;
536                         joydev->abs[i] = dev->abs[j];
537                         continue;
538                 }
539                 joydev->corr[i].type = JS_CORR_BROKEN;
540                 joydev->corr[i].prec = dev->absfuzz[j];
541                 joydev->corr[i].coef[0] = (dev->absmax[j] + dev->absmin[j]) / 2 - dev->absflat[j];
542                 joydev->corr[i].coef[1] = (dev->absmax[j] + dev->absmin[j]) / 2 + dev->absflat[j];
543                 if (!(t = ((dev->absmax[j] - dev->absmin[j]) / 2 - 2 * dev->absflat[j])))
544                         continue;
545                 joydev->corr[i].coef[2] = (1 << 29) / t;
546                 joydev->corr[i].coef[3] = (1 << 29) / t;
547
548                 joydev->abs[i] = joydev_correct(dev->abs[j], joydev->corr + i);
549         }
550
551         joydev_table[minor] = joydev;
552
553         devt = MKDEV(INPUT_MAJOR, JOYDEV_MINOR_BASE + minor),
554
555         cdev = class_device_create(&input_class, &dev->cdev, devt,
556                                    dev->cdev.dev, joydev->name);
557         if (IS_ERR(cdev)) {
558                 error = PTR_ERR(cdev);
559                 goto err_free_joydev;
560         }
561
562         /* temporary symlink to keep userspace happy */
563         error = sysfs_create_link(&input_class.subsys.kobj,
564                                   &cdev->kobj, joydev->name);
565         if (error)
566                 goto err_cdev_destroy;
567
568         error = input_register_handle(&joydev->handle);
569         if (error)
570                 goto err_remove_link;
571
572         return 0;
573
574  err_remove_link:
575         sysfs_remove_link(&input_class.subsys.kobj, joydev->name);
576  err_cdev_destroy:
577         class_device_destroy(&input_class, devt);
578  err_free_joydev:
579         joydev_table[minor] = NULL;
580         kfree(joydev);
581         return error;
582 }
583
584
585 static void joydev_disconnect(struct input_handle *handle)
586 {
587         struct joydev *joydev = handle->private;
588         struct joydev_client *client;
589
590         input_unregister_handle(handle);
591
592         sysfs_remove_link(&input_class.subsys.kobj, joydev->name);
593         class_device_destroy(&input_class, MKDEV(INPUT_MAJOR, JOYDEV_MINOR_BASE + joydev->minor));
594         joydev->exist = 0;
595
596         if (joydev->open) {
597                 input_close_device(handle);
598                 list_for_each_entry(client, &joydev->client_list, node)
599                         kill_fasync(&client->fasync, SIGIO, POLL_HUP);
600                 wake_up_interruptible(&joydev->wait);
601         } else
602                 joydev_free(joydev);
603 }
604
605 static const struct input_device_id joydev_blacklist[] = {
606         {
607                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_KEYBIT,
608                 .evbit = { BIT(EV_KEY) },
609                 .keybit = { [LONG(BTN_TOUCH)] = BIT(BTN_TOUCH) },
610         },      /* Avoid itouchpads, touchscreens and tablets */
611         { }     /* Terminating entry */
612 };
613
614 static const struct input_device_id joydev_ids[] = {
615         {
616                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_ABSBIT,
617                 .evbit = { BIT(EV_ABS) },
618                 .absbit = { BIT(ABS_X) },
619         },
620         {
621                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_ABSBIT,
622                 .evbit = { BIT(EV_ABS) },
623                 .absbit = { BIT(ABS_WHEEL) },
624         },
625         {
626                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_ABSBIT,
627                 .evbit = { BIT(EV_ABS) },
628                 .absbit = { BIT(ABS_THROTTLE) },
629         },
630         { }     /* Terminating entry */
631 };
632
633 MODULE_DEVICE_TABLE(input, joydev_ids);
634
635 static struct input_handler joydev_handler = {
636         .event =        joydev_event,
637         .connect =      joydev_connect,
638         .disconnect =   joydev_disconnect,
639         .fops =         &joydev_fops,
640         .minor =        JOYDEV_MINOR_BASE,
641         .name =         "joydev",
642         .id_table =     joydev_ids,
643         .blacklist =    joydev_blacklist,
644 };
645
646 static int __init joydev_init(void)
647 {
648         return input_register_handler(&joydev_handler);
649 }
650
651 static void __exit joydev_exit(void)
652 {
653         input_unregister_handler(&joydev_handler);
654 }
655
656 module_init(joydev_init);
657 module_exit(joydev_exit);