ata: fix obviously wrong comment
[linux-2.6] / 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/device.h>
28
29 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
30 MODULE_DESCRIPTION("Joystick device interfaces");
31 MODULE_SUPPORTED_DEVICE("input/js");
32 MODULE_LICENSE("GPL");
33
34 #define JOYDEV_MINOR_BASE       0
35 #define JOYDEV_MINORS           16
36 #define JOYDEV_BUFFER_SIZE      64
37
38 struct joydev {
39         int exist;
40         int open;
41         int minor;
42         char name[16];
43         struct input_handle handle;
44         wait_queue_head_t wait;
45         struct list_head client_list;
46         spinlock_t client_lock; /* protects client_list */
47         struct mutex mutex;
48         struct device dev;
49
50         struct js_corr corr[ABS_MAX + 1];
51         struct JS_DATA_SAVE_TYPE glue;
52         int nabs;
53         int nkey;
54         __u16 keymap[KEY_MAX - BTN_MISC + 1];
55         __u16 keypam[KEY_MAX - BTN_MISC + 1];
56         __u8 absmap[ABS_MAX + 1];
57         __u8 abspam[ABS_MAX + 1];
58         __s16 abs[ABS_MAX + 1];
59 };
60
61 struct joydev_client {
62         struct js_event buffer[JOYDEV_BUFFER_SIZE];
63         int head;
64         int tail;
65         int startup;
66         spinlock_t buffer_lock; /* protects access to buffer, head and tail */
67         struct fasync_struct *fasync;
68         struct joydev *joydev;
69         struct list_head node;
70 };
71
72 static struct joydev *joydev_table[JOYDEV_MINORS];
73 static DEFINE_MUTEX(joydev_table_mutex);
74
75 static int joydev_correct(int value, struct js_corr *corr)
76 {
77         switch (corr->type) {
78
79         case JS_CORR_NONE:
80                 break;
81
82         case JS_CORR_BROKEN:
83                 value = value > corr->coef[0] ? (value < corr->coef[1] ? 0 :
84                         ((corr->coef[3] * (value - corr->coef[1])) >> 14)) :
85                         ((corr->coef[2] * (value - corr->coef[0])) >> 14);
86                 break;
87
88         default:
89                 return 0;
90         }
91
92         return value < -32767 ? -32767 : (value > 32767 ? 32767 : value);
93 }
94
95 static void joydev_pass_event(struct joydev_client *client,
96                               struct js_event *event)
97 {
98         struct joydev *joydev = client->joydev;
99
100         /*
101          * IRQs already disabled, just acquire the lock
102          */
103         spin_lock(&client->buffer_lock);
104
105         client->buffer[client->head] = *event;
106
107         if (client->startup == joydev->nabs + joydev->nkey) {
108                 client->head++;
109                 client->head &= JOYDEV_BUFFER_SIZE - 1;
110                 if (client->tail == client->head)
111                         client->startup = 0;
112         }
113
114         spin_unlock(&client->buffer_lock);
115
116         kill_fasync(&client->fasync, SIGIO, POLL_IN);
117 }
118
119 static void joydev_event(struct input_handle *handle,
120                          unsigned int type, unsigned int code, int value)
121 {
122         struct joydev *joydev = handle->private;
123         struct joydev_client *client;
124         struct js_event event;
125
126         switch (type) {
127
128         case EV_KEY:
129                 if (code < BTN_MISC || value == 2)
130                         return;
131                 event.type = JS_EVENT_BUTTON;
132                 event.number = joydev->keymap[code - BTN_MISC];
133                 event.value = value;
134                 break;
135
136         case EV_ABS:
137                 event.type = JS_EVENT_AXIS;
138                 event.number = joydev->absmap[code];
139                 event.value = joydev_correct(value,
140                                         &joydev->corr[event.number]);
141                 if (event.value == joydev->abs[event.number])
142                         return;
143                 joydev->abs[event.number] = event.value;
144                 break;
145
146         default:
147                 return;
148         }
149
150         event.time = jiffies_to_msecs(jiffies);
151
152         rcu_read_lock();
153         list_for_each_entry_rcu(client, &joydev->client_list, node)
154                 joydev_pass_event(client, &event);
155         rcu_read_unlock();
156
157         wake_up_interruptible(&joydev->wait);
158 }
159
160 static int joydev_fasync(int fd, struct file *file, int on)
161 {
162         struct joydev_client *client = file->private_data;
163
164         return fasync_helper(fd, file, on, &client->fasync);
165 }
166
167 static void joydev_free(struct device *dev)
168 {
169         struct joydev *joydev = container_of(dev, struct joydev, dev);
170
171         input_put_device(joydev->handle.dev);
172         kfree(joydev);
173 }
174
175 static void joydev_attach_client(struct joydev *joydev,
176                                  struct joydev_client *client)
177 {
178         spin_lock(&joydev->client_lock);
179         list_add_tail_rcu(&client->node, &joydev->client_list);
180         spin_unlock(&joydev->client_lock);
181         synchronize_rcu();
182 }
183
184 static void joydev_detach_client(struct joydev *joydev,
185                                  struct joydev_client *client)
186 {
187         spin_lock(&joydev->client_lock);
188         list_del_rcu(&client->node);
189         spin_unlock(&joydev->client_lock);
190         synchronize_rcu();
191 }
192
193 static int joydev_open_device(struct joydev *joydev)
194 {
195         int retval;
196
197         retval = mutex_lock_interruptible(&joydev->mutex);
198         if (retval)
199                 return retval;
200
201         if (!joydev->exist)
202                 retval = -ENODEV;
203         else if (!joydev->open++) {
204                 retval = input_open_device(&joydev->handle);
205                 if (retval)
206                         joydev->open--;
207         }
208
209         mutex_unlock(&joydev->mutex);
210         return retval;
211 }
212
213 static void joydev_close_device(struct joydev *joydev)
214 {
215         mutex_lock(&joydev->mutex);
216
217         if (joydev->exist && !--joydev->open)
218                 input_close_device(&joydev->handle);
219
220         mutex_unlock(&joydev->mutex);
221 }
222
223 /*
224  * Wake up users waiting for IO so they can disconnect from
225  * dead device.
226  */
227 static void joydev_hangup(struct joydev *joydev)
228 {
229         struct joydev_client *client;
230
231         spin_lock(&joydev->client_lock);
232         list_for_each_entry(client, &joydev->client_list, node)
233                 kill_fasync(&client->fasync, SIGIO, POLL_HUP);
234         spin_unlock(&joydev->client_lock);
235
236         wake_up_interruptible(&joydev->wait);
237 }
238
239 static int joydev_release(struct inode *inode, struct file *file)
240 {
241         struct joydev_client *client = file->private_data;
242         struct joydev *joydev = client->joydev;
243
244         joydev_detach_client(joydev, client);
245         kfree(client);
246
247         joydev_close_device(joydev);
248         put_device(&joydev->dev);
249
250         return 0;
251 }
252
253 static int joydev_open(struct inode *inode, struct file *file)
254 {
255         struct joydev_client *client;
256         struct joydev *joydev;
257         int i = iminor(inode) - JOYDEV_MINOR_BASE;
258         int error;
259
260         if (i >= JOYDEV_MINORS)
261                 return -ENODEV;
262
263         error = mutex_lock_interruptible(&joydev_table_mutex);
264         if (error)
265                 return error;
266         joydev = joydev_table[i];
267         if (joydev)
268                 get_device(&joydev->dev);
269         mutex_unlock(&joydev_table_mutex);
270
271         if (!joydev)
272                 return -ENODEV;
273
274         client = kzalloc(sizeof(struct joydev_client), GFP_KERNEL);
275         if (!client) {
276                 error = -ENOMEM;
277                 goto err_put_joydev;
278         }
279
280         spin_lock_init(&client->buffer_lock);
281         client->joydev = joydev;
282         joydev_attach_client(joydev, client);
283
284         error = joydev_open_device(joydev);
285         if (error)
286                 goto err_free_client;
287
288         file->private_data = client;
289         return 0;
290
291  err_free_client:
292         joydev_detach_client(joydev, client);
293         kfree(client);
294  err_put_joydev:
295         put_device(&joydev->dev);
296         return error;
297 }
298
299 static int joydev_generate_startup_event(struct joydev_client *client,
300                                          struct input_dev *input,
301                                          struct js_event *event)
302 {
303         struct joydev *joydev = client->joydev;
304         int have_event;
305
306         spin_lock_irq(&client->buffer_lock);
307
308         have_event = client->startup < joydev->nabs + joydev->nkey;
309
310         if (have_event) {
311
312                 event->time = jiffies_to_msecs(jiffies);
313                 if (client->startup < joydev->nkey) {
314                         event->type = JS_EVENT_BUTTON | JS_EVENT_INIT;
315                         event->number = client->startup;
316                         event->value = !!test_bit(joydev->keypam[event->number],
317                                                   input->key);
318                 } else {
319                         event->type = JS_EVENT_AXIS | JS_EVENT_INIT;
320                         event->number = client->startup - joydev->nkey;
321                         event->value = joydev->abs[event->number];
322                 }
323                 client->startup++;
324         }
325
326         spin_unlock_irq(&client->buffer_lock);
327
328         return have_event;
329 }
330
331 static int joydev_fetch_next_event(struct joydev_client *client,
332                                    struct js_event *event)
333 {
334         int have_event;
335
336         spin_lock_irq(&client->buffer_lock);
337
338         have_event = client->head != client->tail;
339         if (have_event) {
340                 *event = client->buffer[client->tail++];
341                 client->tail &= JOYDEV_BUFFER_SIZE - 1;
342         }
343
344         spin_unlock_irq(&client->buffer_lock);
345
346         return have_event;
347 }
348
349 /*
350  * Old joystick interface
351  */
352 static ssize_t joydev_0x_read(struct joydev_client *client,
353                               struct input_dev *input,
354                               char __user *buf)
355 {
356         struct joydev *joydev = client->joydev;
357         struct JS_DATA_TYPE data;
358         int i;
359
360         spin_lock_irq(&input->event_lock);
361
362         /*
363          * Get device state
364          */
365         for (data.buttons = i = 0; i < 32 && i < joydev->nkey; i++)
366                 data.buttons |=
367                         test_bit(joydev->keypam[i], input->key) ? (1 << i) : 0;
368         data.x = (joydev->abs[0] / 256 + 128) >> joydev->glue.JS_CORR.x;
369         data.y = (joydev->abs[1] / 256 + 128) >> joydev->glue.JS_CORR.y;
370
371         /*
372          * Reset reader's event queue
373          */
374         spin_lock(&client->buffer_lock);
375         client->startup = 0;
376         client->tail = client->head;
377         spin_unlock(&client->buffer_lock);
378
379         spin_unlock_irq(&input->event_lock);
380
381         if (copy_to_user(buf, &data, sizeof(struct JS_DATA_TYPE)))
382                 return -EFAULT;
383
384         return sizeof(struct JS_DATA_TYPE);
385 }
386
387 static inline int joydev_data_pending(struct joydev_client *client)
388 {
389         struct joydev *joydev = client->joydev;
390
391         return client->startup < joydev->nabs + joydev->nkey ||
392                 client->head != client->tail;
393 }
394
395 static ssize_t joydev_read(struct file *file, char __user *buf,
396                            size_t count, loff_t *ppos)
397 {
398         struct joydev_client *client = file->private_data;
399         struct joydev *joydev = client->joydev;
400         struct input_dev *input = joydev->handle.dev;
401         struct js_event event;
402         int retval;
403
404         if (!joydev->exist)
405                 return -ENODEV;
406
407         if (count < sizeof(struct js_event))
408                 return -EINVAL;
409
410         if (count == sizeof(struct JS_DATA_TYPE))
411                 return joydev_0x_read(client, input, buf);
412
413         if (!joydev_data_pending(client) && (file->f_flags & O_NONBLOCK))
414                 return -EAGAIN;
415
416         retval = wait_event_interruptible(joydev->wait,
417                         !joydev->exist || joydev_data_pending(client));
418         if (retval)
419                 return retval;
420
421         if (!joydev->exist)
422                 return -ENODEV;
423
424         while (retval + sizeof(struct js_event) <= count &&
425                joydev_generate_startup_event(client, input, &event)) {
426
427                 if (copy_to_user(buf + retval, &event, sizeof(struct js_event)))
428                         return -EFAULT;
429
430                 retval += sizeof(struct js_event);
431         }
432
433         while (retval + sizeof(struct js_event) <= count &&
434                joydev_fetch_next_event(client, &event)) {
435
436                 if (copy_to_user(buf + retval, &event, sizeof(struct js_event)))
437                         return -EFAULT;
438
439                 retval += sizeof(struct js_event);
440         }
441
442         return retval;
443 }
444
445 /* No kernel lock - fine */
446 static unsigned int joydev_poll(struct file *file, poll_table *wait)
447 {
448         struct joydev_client *client = file->private_data;
449         struct joydev *joydev = client->joydev;
450
451         poll_wait(file, &joydev->wait, wait);
452         return (joydev_data_pending(client) ? (POLLIN | POLLRDNORM) : 0) |
453                 (joydev->exist ?  0 : (POLLHUP | POLLERR));
454 }
455
456 static int joydev_ioctl_common(struct joydev *joydev,
457                                 unsigned int cmd, void __user *argp)
458 {
459         struct input_dev *dev = joydev->handle.dev;
460         int i, j;
461
462         switch (cmd) {
463
464         case JS_SET_CAL:
465                 return copy_from_user(&joydev->glue.JS_CORR, argp,
466                                 sizeof(joydev->glue.JS_CORR)) ? -EFAULT : 0;
467
468         case JS_GET_CAL:
469                 return copy_to_user(argp, &joydev->glue.JS_CORR,
470                                 sizeof(joydev->glue.JS_CORR)) ? -EFAULT : 0;
471
472         case JS_SET_TIMEOUT:
473                 return get_user(joydev->glue.JS_TIMEOUT, (s32 __user *) argp);
474
475         case JS_GET_TIMEOUT:
476                 return put_user(joydev->glue.JS_TIMEOUT, (s32 __user *) argp);
477
478         case JSIOCGVERSION:
479                 return put_user(JS_VERSION, (__u32 __user *) argp);
480
481         case JSIOCGAXES:
482                 return put_user(joydev->nabs, (__u8 __user *) argp);
483
484         case JSIOCGBUTTONS:
485                 return put_user(joydev->nkey, (__u8 __user *) argp);
486
487         case JSIOCSCORR:
488                 if (copy_from_user(joydev->corr, argp,
489                               sizeof(joydev->corr[0]) * joydev->nabs))
490                     return -EFAULT;
491
492                 for (i = 0; i < joydev->nabs; i++) {
493                         j = joydev->abspam[i];
494                         joydev->abs[i] = joydev_correct(dev->abs[j],
495                                                         &joydev->corr[i]);
496                 }
497                 return 0;
498
499         case JSIOCGCORR:
500                 return copy_to_user(argp, joydev->corr,
501                         sizeof(joydev->corr[0]) * joydev->nabs) ? -EFAULT : 0;
502
503         case JSIOCSAXMAP:
504                 if (copy_from_user(joydev->abspam, argp,
505                                    sizeof(__u8) * (ABS_MAX + 1)))
506                         return -EFAULT;
507
508                 for (i = 0; i < joydev->nabs; i++) {
509                         if (joydev->abspam[i] > ABS_MAX)
510                                 return -EINVAL;
511                         joydev->absmap[joydev->abspam[i]] = i;
512                 }
513                 return 0;
514
515         case JSIOCGAXMAP:
516                 return copy_to_user(argp, joydev->abspam,
517                         sizeof(__u8) * (ABS_MAX + 1)) ? -EFAULT : 0;
518
519         case JSIOCSBTNMAP:
520                 if (copy_from_user(joydev->keypam, argp,
521                                    sizeof(__u16) * (KEY_MAX - BTN_MISC + 1)))
522                         return -EFAULT;
523
524                 for (i = 0; i < joydev->nkey; i++) {
525                         if (joydev->keypam[i] > KEY_MAX ||
526                             joydev->keypam[i] < BTN_MISC)
527                                 return -EINVAL;
528                         joydev->keymap[joydev->keypam[i] - BTN_MISC] = i;
529                 }
530
531                 return 0;
532
533         case JSIOCGBTNMAP:
534                 return copy_to_user(argp, joydev->keypam,
535                         sizeof(__u16) * (KEY_MAX - BTN_MISC + 1)) ? -EFAULT : 0;
536
537         default:
538                 if ((cmd & ~IOCSIZE_MASK) == JSIOCGNAME(0)) {
539                         int len;
540                         if (!dev->name)
541                                 return 0;
542                         len = strlen(dev->name) + 1;
543                         if (len > _IOC_SIZE(cmd))
544                                 len = _IOC_SIZE(cmd);
545                         if (copy_to_user(argp, dev->name, len))
546                                 return -EFAULT;
547                         return len;
548                 }
549         }
550         return -EINVAL;
551 }
552
553 #ifdef CONFIG_COMPAT
554 static long joydev_compat_ioctl(struct file *file,
555                                 unsigned int cmd, unsigned long arg)
556 {
557         struct joydev_client *client = file->private_data;
558         struct joydev *joydev = client->joydev;
559         void __user *argp = (void __user *)arg;
560         s32 tmp32;
561         struct JS_DATA_SAVE_TYPE_32 ds32;
562         int retval;
563
564         retval = mutex_lock_interruptible(&joydev->mutex);
565         if (retval)
566                 return retval;
567
568         if (!joydev->exist) {
569                 retval = -ENODEV;
570                 goto out;
571         }
572
573         switch (cmd) {
574
575         case JS_SET_TIMELIMIT:
576                 retval = get_user(tmp32, (s32 __user *) arg);
577                 if (retval == 0)
578                         joydev->glue.JS_TIMELIMIT = tmp32;
579                 break;
580
581         case JS_GET_TIMELIMIT:
582                 tmp32 = joydev->glue.JS_TIMELIMIT;
583                 retval = put_user(tmp32, (s32 __user *) arg);
584                 break;
585
586         case JS_SET_ALL:
587                 retval = copy_from_user(&ds32, argp,
588                                         sizeof(ds32)) ? -EFAULT : 0;
589                 if (retval == 0) {
590                         joydev->glue.JS_TIMEOUT    = ds32.JS_TIMEOUT;
591                         joydev->glue.BUSY          = ds32.BUSY;
592                         joydev->glue.JS_EXPIRETIME = ds32.JS_EXPIRETIME;
593                         joydev->glue.JS_TIMELIMIT  = ds32.JS_TIMELIMIT;
594                         joydev->glue.JS_SAVE       = ds32.JS_SAVE;
595                         joydev->glue.JS_CORR       = ds32.JS_CORR;
596                 }
597                 break;
598
599         case JS_GET_ALL:
600                 ds32.JS_TIMEOUT    = joydev->glue.JS_TIMEOUT;
601                 ds32.BUSY          = joydev->glue.BUSY;
602                 ds32.JS_EXPIRETIME = joydev->glue.JS_EXPIRETIME;
603                 ds32.JS_TIMELIMIT  = joydev->glue.JS_TIMELIMIT;
604                 ds32.JS_SAVE       = joydev->glue.JS_SAVE;
605                 ds32.JS_CORR       = joydev->glue.JS_CORR;
606
607                 retval = copy_to_user(argp, &ds32, sizeof(ds32)) ? -EFAULT : 0;
608                 break;
609
610         default:
611                 retval = joydev_ioctl_common(joydev, cmd, argp);
612                 break;
613         }
614
615  out:
616         mutex_unlock(&joydev->mutex);
617         return retval;
618 }
619 #endif /* CONFIG_COMPAT */
620
621 static long joydev_ioctl(struct file *file,
622                          unsigned int cmd, unsigned long arg)
623 {
624         struct joydev_client *client = file->private_data;
625         struct joydev *joydev = client->joydev;
626         void __user *argp = (void __user *)arg;
627         int retval;
628
629         retval = mutex_lock_interruptible(&joydev->mutex);
630         if (retval)
631                 return retval;
632
633         if (!joydev->exist) {
634                 retval = -ENODEV;
635                 goto out;
636         }
637
638         switch (cmd) {
639
640         case JS_SET_TIMELIMIT:
641                 retval = get_user(joydev->glue.JS_TIMELIMIT,
642                                   (long __user *) arg);
643                 break;
644
645         case JS_GET_TIMELIMIT:
646                 retval = put_user(joydev->glue.JS_TIMELIMIT,
647                                   (long __user *) arg);
648                 break;
649
650         case JS_SET_ALL:
651                 retval = copy_from_user(&joydev->glue, argp,
652                                         sizeof(joydev->glue)) ? -EFAULT: 0;
653                 break;
654
655         case JS_GET_ALL:
656                 retval = copy_to_user(argp, &joydev->glue,
657                                       sizeof(joydev->glue)) ? -EFAULT : 0;
658                 break;
659
660         default:
661                 retval = joydev_ioctl_common(joydev, cmd, argp);
662                 break;
663         }
664  out:
665         mutex_unlock(&joydev->mutex);
666         return retval;
667 }
668
669 static const struct file_operations joydev_fops = {
670         .owner          = THIS_MODULE,
671         .read           = joydev_read,
672         .poll           = joydev_poll,
673         .open           = joydev_open,
674         .release        = joydev_release,
675         .unlocked_ioctl = joydev_ioctl,
676 #ifdef CONFIG_COMPAT
677         .compat_ioctl   = joydev_compat_ioctl,
678 #endif
679         .fasync         = joydev_fasync,
680 };
681
682 static int joydev_install_chrdev(struct joydev *joydev)
683 {
684         joydev_table[joydev->minor] = joydev;
685         return 0;
686 }
687
688 static void joydev_remove_chrdev(struct joydev *joydev)
689 {
690         mutex_lock(&joydev_table_mutex);
691         joydev_table[joydev->minor] = NULL;
692         mutex_unlock(&joydev_table_mutex);
693 }
694
695 /*
696  * Mark device non-existant. This disables writes, ioctls and
697  * prevents new users from opening the device. Already posted
698  * blocking reads will stay, however new ones will fail.
699  */
700 static void joydev_mark_dead(struct joydev *joydev)
701 {
702         mutex_lock(&joydev->mutex);
703         joydev->exist = 0;
704         mutex_unlock(&joydev->mutex);
705 }
706
707 static void joydev_cleanup(struct joydev *joydev)
708 {
709         struct input_handle *handle = &joydev->handle;
710
711         joydev_mark_dead(joydev);
712         joydev_hangup(joydev);
713         joydev_remove_chrdev(joydev);
714
715         /* joydev is marked dead so noone else accesses joydev->open */
716         if (joydev->open)
717                 input_close_device(handle);
718 }
719
720 static int joydev_connect(struct input_handler *handler, struct input_dev *dev,
721                           const struct input_device_id *id)
722 {
723         struct joydev *joydev;
724         int i, j, t, minor;
725         int error;
726
727         for (minor = 0; minor < JOYDEV_MINORS; minor++)
728                 if (!joydev_table[minor])
729                         break;
730
731         if (minor == JOYDEV_MINORS) {
732                 printk(KERN_ERR "joydev: no more free joydev devices\n");
733                 return -ENFILE;
734         }
735
736         joydev = kzalloc(sizeof(struct joydev), GFP_KERNEL);
737         if (!joydev)
738                 return -ENOMEM;
739
740         INIT_LIST_HEAD(&joydev->client_list);
741         spin_lock_init(&joydev->client_lock);
742         mutex_init(&joydev->mutex);
743         init_waitqueue_head(&joydev->wait);
744
745         snprintf(joydev->name, sizeof(joydev->name), "js%d", minor);
746         joydev->exist = 1;
747         joydev->minor = minor;
748
749         joydev->exist = 1;
750         joydev->handle.dev = input_get_device(dev);
751         joydev->handle.name = joydev->name;
752         joydev->handle.handler = handler;
753         joydev->handle.private = joydev;
754
755         for (i = 0; i < ABS_MAX + 1; i++)
756                 if (test_bit(i, dev->absbit)) {
757                         joydev->absmap[i] = joydev->nabs;
758                         joydev->abspam[joydev->nabs] = i;
759                         joydev->nabs++;
760                 }
761
762         for (i = BTN_JOYSTICK - BTN_MISC; i < KEY_MAX - BTN_MISC + 1; i++)
763                 if (test_bit(i + BTN_MISC, dev->keybit)) {
764                         joydev->keymap[i] = joydev->nkey;
765                         joydev->keypam[joydev->nkey] = i + BTN_MISC;
766                         joydev->nkey++;
767                 }
768
769         for (i = 0; i < BTN_JOYSTICK - BTN_MISC; i++)
770                 if (test_bit(i + BTN_MISC, dev->keybit)) {
771                         joydev->keymap[i] = joydev->nkey;
772                         joydev->keypam[joydev->nkey] = i + BTN_MISC;
773                         joydev->nkey++;
774                 }
775
776         for (i = 0; i < joydev->nabs; i++) {
777                 j = joydev->abspam[i];
778                 if (dev->absmax[j] == dev->absmin[j]) {
779                         joydev->corr[i].type = JS_CORR_NONE;
780                         joydev->abs[i] = dev->abs[j];
781                         continue;
782                 }
783                 joydev->corr[i].type = JS_CORR_BROKEN;
784                 joydev->corr[i].prec = dev->absfuzz[j];
785                 joydev->corr[i].coef[0] =
786                         (dev->absmax[j] + dev->absmin[j]) / 2 - dev->absflat[j];
787                 joydev->corr[i].coef[1] =
788                         (dev->absmax[j] + dev->absmin[j]) / 2 + dev->absflat[j];
789
790                 t = (dev->absmax[j] - dev->absmin[j]) / 2 - 2 * dev->absflat[j];
791                 if (t) {
792                         joydev->corr[i].coef[2] = (1 << 29) / t;
793                         joydev->corr[i].coef[3] = (1 << 29) / t;
794
795                         joydev->abs[i] = joydev_correct(dev->abs[j],
796                                                         joydev->corr + i);
797                 }
798         }
799
800         dev_set_name(&joydev->dev, joydev->name);
801         joydev->dev.devt = MKDEV(INPUT_MAJOR, JOYDEV_MINOR_BASE + minor);
802         joydev->dev.class = &input_class;
803         joydev->dev.parent = &dev->dev;
804         joydev->dev.release = joydev_free;
805         device_initialize(&joydev->dev);
806
807         error = input_register_handle(&joydev->handle);
808         if (error)
809                 goto err_free_joydev;
810
811         error = joydev_install_chrdev(joydev);
812         if (error)
813                 goto err_unregister_handle;
814
815         error = device_add(&joydev->dev);
816         if (error)
817                 goto err_cleanup_joydev;
818
819         return 0;
820
821  err_cleanup_joydev:
822         joydev_cleanup(joydev);
823  err_unregister_handle:
824         input_unregister_handle(&joydev->handle);
825  err_free_joydev:
826         put_device(&joydev->dev);
827         return error;
828 }
829
830 static void joydev_disconnect(struct input_handle *handle)
831 {
832         struct joydev *joydev = handle->private;
833
834         device_del(&joydev->dev);
835         joydev_cleanup(joydev);
836         input_unregister_handle(handle);
837         put_device(&joydev->dev);
838 }
839
840 static const struct input_device_id joydev_blacklist[] = {
841         {
842                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
843                                 INPUT_DEVICE_ID_MATCH_KEYBIT,
844                 .evbit = { BIT_MASK(EV_KEY) },
845                 .keybit = { [BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH) },
846         },      /* Avoid itouchpads, touchscreens and tablets */
847         { }     /* Terminating entry */
848 };
849
850 static const struct input_device_id joydev_ids[] = {
851         {
852                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
853                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
854                 .evbit = { BIT_MASK(EV_ABS) },
855                 .absbit = { BIT_MASK(ABS_X) },
856         },
857         {
858                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
859                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
860                 .evbit = { BIT_MASK(EV_ABS) },
861                 .absbit = { BIT_MASK(ABS_WHEEL) },
862         },
863         {
864                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
865                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
866                 .evbit = { BIT_MASK(EV_ABS) },
867                 .absbit = { BIT_MASK(ABS_THROTTLE) },
868         },
869         { }     /* Terminating entry */
870 };
871
872 MODULE_DEVICE_TABLE(input, joydev_ids);
873
874 static struct input_handler joydev_handler = {
875         .event          = joydev_event,
876         .connect        = joydev_connect,
877         .disconnect     = joydev_disconnect,
878         .fops           = &joydev_fops,
879         .minor          = JOYDEV_MINOR_BASE,
880         .name           = "joydev",
881         .id_table       = joydev_ids,
882         .blacklist      = joydev_blacklist,
883 };
884
885 static int __init joydev_init(void)
886 {
887         return input_register_handler(&joydev_handler);
888 }
889
890 static void __exit joydev_exit(void)
891 {
892         input_unregister_handler(&joydev_handler);
893 }
894
895 module_init(joydev_init);
896 module_exit(joydev_exit);