Merge branch 'llseek' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl
[linux-2.6-microblaze.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/sched.h>
22 #include <linux/slab.h>
23 #include <linux/mm.h>
24 #include <linux/miscdevice.h>
25 #include <linux/module.h>
26 #include <linux/poll.h>
27 #include <linux/init.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 open;
41         int minor;
42         struct input_handle handle;
43         wait_queue_head_t wait;
44         struct list_head client_list;
45         spinlock_t client_lock; /* protects client_list */
46         struct mutex mutex;
47         struct device dev;
48         bool exist;
49
50         struct js_corr corr[ABS_CNT];
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_CNT];
57         __u8 abspam[ABS_CNT];
58         __s16 abs[ABS_CNT];
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         nonseekable_open(inode, file);
290
291         return 0;
292
293  err_free_client:
294         joydev_detach_client(joydev, client);
295         kfree(client);
296  err_put_joydev:
297         put_device(&joydev->dev);
298         return error;
299 }
300
301 static int joydev_generate_startup_event(struct joydev_client *client,
302                                          struct input_dev *input,
303                                          struct js_event *event)
304 {
305         struct joydev *joydev = client->joydev;
306         int have_event;
307
308         spin_lock_irq(&client->buffer_lock);
309
310         have_event = client->startup < joydev->nabs + joydev->nkey;
311
312         if (have_event) {
313
314                 event->time = jiffies_to_msecs(jiffies);
315                 if (client->startup < joydev->nkey) {
316                         event->type = JS_EVENT_BUTTON | JS_EVENT_INIT;
317                         event->number = client->startup;
318                         event->value = !!test_bit(joydev->keypam[event->number],
319                                                   input->key);
320                 } else {
321                         event->type = JS_EVENT_AXIS | JS_EVENT_INIT;
322                         event->number = client->startup - joydev->nkey;
323                         event->value = joydev->abs[event->number];
324                 }
325                 client->startup++;
326         }
327
328         spin_unlock_irq(&client->buffer_lock);
329
330         return have_event;
331 }
332
333 static int joydev_fetch_next_event(struct joydev_client *client,
334                                    struct js_event *event)
335 {
336         int have_event;
337
338         spin_lock_irq(&client->buffer_lock);
339
340         have_event = client->head != client->tail;
341         if (have_event) {
342                 *event = client->buffer[client->tail++];
343                 client->tail &= JOYDEV_BUFFER_SIZE - 1;
344         }
345
346         spin_unlock_irq(&client->buffer_lock);
347
348         return have_event;
349 }
350
351 /*
352  * Old joystick interface
353  */
354 static ssize_t joydev_0x_read(struct joydev_client *client,
355                               struct input_dev *input,
356                               char __user *buf)
357 {
358         struct joydev *joydev = client->joydev;
359         struct JS_DATA_TYPE data;
360         int i;
361
362         spin_lock_irq(&input->event_lock);
363
364         /*
365          * Get device state
366          */
367         for (data.buttons = i = 0; i < 32 && i < joydev->nkey; i++)
368                 data.buttons |=
369                         test_bit(joydev->keypam[i], input->key) ? (1 << i) : 0;
370         data.x = (joydev->abs[0] / 256 + 128) >> joydev->glue.JS_CORR.x;
371         data.y = (joydev->abs[1] / 256 + 128) >> joydev->glue.JS_CORR.y;
372
373         /*
374          * Reset reader's event queue
375          */
376         spin_lock(&client->buffer_lock);
377         client->startup = 0;
378         client->tail = client->head;
379         spin_unlock(&client->buffer_lock);
380
381         spin_unlock_irq(&input->event_lock);
382
383         if (copy_to_user(buf, &data, sizeof(struct JS_DATA_TYPE)))
384                 return -EFAULT;
385
386         return sizeof(struct JS_DATA_TYPE);
387 }
388
389 static inline int joydev_data_pending(struct joydev_client *client)
390 {
391         struct joydev *joydev = client->joydev;
392
393         return client->startup < joydev->nabs + joydev->nkey ||
394                 client->head != client->tail;
395 }
396
397 static ssize_t joydev_read(struct file *file, char __user *buf,
398                            size_t count, loff_t *ppos)
399 {
400         struct joydev_client *client = file->private_data;
401         struct joydev *joydev = client->joydev;
402         struct input_dev *input = joydev->handle.dev;
403         struct js_event event;
404         int retval;
405
406         if (!joydev->exist)
407                 return -ENODEV;
408
409         if (count < sizeof(struct js_event))
410                 return -EINVAL;
411
412         if (count == sizeof(struct JS_DATA_TYPE))
413                 return joydev_0x_read(client, input, buf);
414
415         if (!joydev_data_pending(client) && (file->f_flags & O_NONBLOCK))
416                 return -EAGAIN;
417
418         retval = wait_event_interruptible(joydev->wait,
419                         !joydev->exist || joydev_data_pending(client));
420         if (retval)
421                 return retval;
422
423         if (!joydev->exist)
424                 return -ENODEV;
425
426         while (retval + sizeof(struct js_event) <= count &&
427                joydev_generate_startup_event(client, input, &event)) {
428
429                 if (copy_to_user(buf + retval, &event, sizeof(struct js_event)))
430                         return -EFAULT;
431
432                 retval += sizeof(struct js_event);
433         }
434
435         while (retval + sizeof(struct js_event) <= count &&
436                joydev_fetch_next_event(client, &event)) {
437
438                 if (copy_to_user(buf + retval, &event, sizeof(struct js_event)))
439                         return -EFAULT;
440
441                 retval += sizeof(struct js_event);
442         }
443
444         return retval;
445 }
446
447 /* No kernel lock - fine */
448 static unsigned int joydev_poll(struct file *file, poll_table *wait)
449 {
450         struct joydev_client *client = file->private_data;
451         struct joydev *joydev = client->joydev;
452
453         poll_wait(file, &joydev->wait, wait);
454         return (joydev_data_pending(client) ? (POLLIN | POLLRDNORM) : 0) |
455                 (joydev->exist ?  0 : (POLLHUP | POLLERR));
456 }
457
458 static int joydev_handle_JSIOCSAXMAP(struct joydev *joydev,
459                                      void __user *argp, size_t len)
460 {
461         __u8 *abspam;
462         int i;
463         int retval = 0;
464
465         len = min(len, sizeof(joydev->abspam));
466
467         /* Validate the map. */
468         abspam = kmalloc(len, GFP_KERNEL);
469         if (!abspam)
470                 return -ENOMEM;
471
472         if (copy_from_user(abspam, argp, len)) {
473                 retval = -EFAULT;
474                 goto out;
475         }
476
477         for (i = 0; i < joydev->nabs; i++) {
478                 if (abspam[i] > ABS_MAX) {
479                         retval = -EINVAL;
480                         goto out;
481                 }
482         }
483
484         memcpy(joydev->abspam, abspam, len);
485
486         for (i = 0; i < joydev->nabs; i++)
487                 joydev->absmap[joydev->abspam[i]] = i;
488
489  out:
490         kfree(abspam);
491         return retval;
492 }
493
494 static int joydev_handle_JSIOCSBTNMAP(struct joydev *joydev,
495                                       void __user *argp, size_t len)
496 {
497         __u16 *keypam;
498         int i;
499         int retval = 0;
500
501         len = min(len, sizeof(joydev->keypam));
502
503         /* Validate the map. */
504         keypam = kmalloc(len, GFP_KERNEL);
505         if (!keypam)
506                 return -ENOMEM;
507
508         if (copy_from_user(keypam, argp, len)) {
509                 retval = -EFAULT;
510                 goto out;
511         }
512
513         for (i = 0; i < joydev->nkey; i++) {
514                 if (keypam[i] > KEY_MAX || keypam[i] < BTN_MISC) {
515                         retval = -EINVAL;
516                         goto out;
517                 }
518         }
519
520         memcpy(joydev->keypam, keypam, len);
521
522         for (i = 0; i < joydev->nkey; i++)
523                 joydev->keymap[keypam[i] - BTN_MISC] = i;
524
525  out:
526         kfree(keypam);
527         return retval;
528 }
529
530
531 static int joydev_ioctl_common(struct joydev *joydev,
532                                 unsigned int cmd, void __user *argp)
533 {
534         struct input_dev *dev = joydev->handle.dev;
535         size_t len;
536         int i;
537         const char *name;
538
539         /* Process fixed-sized commands. */
540         switch (cmd) {
541
542         case JS_SET_CAL:
543                 return copy_from_user(&joydev->glue.JS_CORR, argp,
544                                 sizeof(joydev->glue.JS_CORR)) ? -EFAULT : 0;
545
546         case JS_GET_CAL:
547                 return copy_to_user(argp, &joydev->glue.JS_CORR,
548                                 sizeof(joydev->glue.JS_CORR)) ? -EFAULT : 0;
549
550         case JS_SET_TIMEOUT:
551                 return get_user(joydev->glue.JS_TIMEOUT, (s32 __user *) argp);
552
553         case JS_GET_TIMEOUT:
554                 return put_user(joydev->glue.JS_TIMEOUT, (s32 __user *) argp);
555
556         case JSIOCGVERSION:
557                 return put_user(JS_VERSION, (__u32 __user *) argp);
558
559         case JSIOCGAXES:
560                 return put_user(joydev->nabs, (__u8 __user *) argp);
561
562         case JSIOCGBUTTONS:
563                 return put_user(joydev->nkey, (__u8 __user *) argp);
564
565         case JSIOCSCORR:
566                 if (copy_from_user(joydev->corr, argp,
567                               sizeof(joydev->corr[0]) * joydev->nabs))
568                         return -EFAULT;
569
570                 for (i = 0; i < joydev->nabs; i++) {
571                         int val = input_abs_get_val(dev, joydev->abspam[i]);
572                         joydev->abs[i] = joydev_correct(val, &joydev->corr[i]);
573                 }
574                 return 0;
575
576         case JSIOCGCORR:
577                 return copy_to_user(argp, joydev->corr,
578                         sizeof(joydev->corr[0]) * joydev->nabs) ? -EFAULT : 0;
579
580         }
581
582         /*
583          * Process variable-sized commands (the axis and button map commands
584          * are considered variable-sized to decouple them from the values of
585          * ABS_MAX and KEY_MAX).
586          */
587         switch (cmd & ~IOCSIZE_MASK) {
588
589         case (JSIOCSAXMAP & ~IOCSIZE_MASK):
590                 return joydev_handle_JSIOCSAXMAP(joydev, argp, _IOC_SIZE(cmd));
591
592         case (JSIOCGAXMAP & ~IOCSIZE_MASK):
593                 len = min_t(size_t, _IOC_SIZE(cmd), sizeof(joydev->abspam));
594                 return copy_to_user(argp, joydev->abspam, len) ? -EFAULT : len;
595
596         case (JSIOCSBTNMAP & ~IOCSIZE_MASK):
597                 return joydev_handle_JSIOCSBTNMAP(joydev, argp, _IOC_SIZE(cmd));
598
599         case (JSIOCGBTNMAP & ~IOCSIZE_MASK):
600                 len = min_t(size_t, _IOC_SIZE(cmd), sizeof(joydev->keypam));
601                 return copy_to_user(argp, joydev->keypam, len) ? -EFAULT : len;
602
603         case JSIOCGNAME(0):
604                 name = dev->name;
605                 if (!name)
606                         return 0;
607
608                 len = min_t(size_t, _IOC_SIZE(cmd), strlen(name) + 1);
609                 return copy_to_user(argp, name, len) ? -EFAULT : len;
610         }
611
612         return -EINVAL;
613 }
614
615 #ifdef CONFIG_COMPAT
616 static long joydev_compat_ioctl(struct file *file,
617                                 unsigned int cmd, unsigned long arg)
618 {
619         struct joydev_client *client = file->private_data;
620         struct joydev *joydev = client->joydev;
621         void __user *argp = (void __user *)arg;
622         s32 tmp32;
623         struct JS_DATA_SAVE_TYPE_32 ds32;
624         int retval;
625
626         retval = mutex_lock_interruptible(&joydev->mutex);
627         if (retval)
628                 return retval;
629
630         if (!joydev->exist) {
631                 retval = -ENODEV;
632                 goto out;
633         }
634
635         switch (cmd) {
636
637         case JS_SET_TIMELIMIT:
638                 retval = get_user(tmp32, (s32 __user *) arg);
639                 if (retval == 0)
640                         joydev->glue.JS_TIMELIMIT = tmp32;
641                 break;
642
643         case JS_GET_TIMELIMIT:
644                 tmp32 = joydev->glue.JS_TIMELIMIT;
645                 retval = put_user(tmp32, (s32 __user *) arg);
646                 break;
647
648         case JS_SET_ALL:
649                 retval = copy_from_user(&ds32, argp,
650                                         sizeof(ds32)) ? -EFAULT : 0;
651                 if (retval == 0) {
652                         joydev->glue.JS_TIMEOUT    = ds32.JS_TIMEOUT;
653                         joydev->glue.BUSY          = ds32.BUSY;
654                         joydev->glue.JS_EXPIRETIME = ds32.JS_EXPIRETIME;
655                         joydev->glue.JS_TIMELIMIT  = ds32.JS_TIMELIMIT;
656                         joydev->glue.JS_SAVE       = ds32.JS_SAVE;
657                         joydev->glue.JS_CORR       = ds32.JS_CORR;
658                 }
659                 break;
660
661         case JS_GET_ALL:
662                 ds32.JS_TIMEOUT    = joydev->glue.JS_TIMEOUT;
663                 ds32.BUSY          = joydev->glue.BUSY;
664                 ds32.JS_EXPIRETIME = joydev->glue.JS_EXPIRETIME;
665                 ds32.JS_TIMELIMIT  = joydev->glue.JS_TIMELIMIT;
666                 ds32.JS_SAVE       = joydev->glue.JS_SAVE;
667                 ds32.JS_CORR       = joydev->glue.JS_CORR;
668
669                 retval = copy_to_user(argp, &ds32, sizeof(ds32)) ? -EFAULT : 0;
670                 break;
671
672         default:
673                 retval = joydev_ioctl_common(joydev, cmd, argp);
674                 break;
675         }
676
677  out:
678         mutex_unlock(&joydev->mutex);
679         return retval;
680 }
681 #endif /* CONFIG_COMPAT */
682
683 static long joydev_ioctl(struct file *file,
684                          unsigned int cmd, unsigned long arg)
685 {
686         struct joydev_client *client = file->private_data;
687         struct joydev *joydev = client->joydev;
688         void __user *argp = (void __user *)arg;
689         int retval;
690
691         retval = mutex_lock_interruptible(&joydev->mutex);
692         if (retval)
693                 return retval;
694
695         if (!joydev->exist) {
696                 retval = -ENODEV;
697                 goto out;
698         }
699
700         switch (cmd) {
701
702         case JS_SET_TIMELIMIT:
703                 retval = get_user(joydev->glue.JS_TIMELIMIT,
704                                   (long __user *) arg);
705                 break;
706
707         case JS_GET_TIMELIMIT:
708                 retval = put_user(joydev->glue.JS_TIMELIMIT,
709                                   (long __user *) arg);
710                 break;
711
712         case JS_SET_ALL:
713                 retval = copy_from_user(&joydev->glue, argp,
714                                         sizeof(joydev->glue)) ? -EFAULT: 0;
715                 break;
716
717         case JS_GET_ALL:
718                 retval = copy_to_user(argp, &joydev->glue,
719                                       sizeof(joydev->glue)) ? -EFAULT : 0;
720                 break;
721
722         default:
723                 retval = joydev_ioctl_common(joydev, cmd, argp);
724                 break;
725         }
726  out:
727         mutex_unlock(&joydev->mutex);
728         return retval;
729 }
730
731 static const struct file_operations joydev_fops = {
732         .owner          = THIS_MODULE,
733         .read           = joydev_read,
734         .poll           = joydev_poll,
735         .open           = joydev_open,
736         .release        = joydev_release,
737         .unlocked_ioctl = joydev_ioctl,
738 #ifdef CONFIG_COMPAT
739         .compat_ioctl   = joydev_compat_ioctl,
740 #endif
741         .fasync         = joydev_fasync,
742         .llseek         = no_llseek,
743 };
744
745 static int joydev_install_chrdev(struct joydev *joydev)
746 {
747         joydev_table[joydev->minor] = joydev;
748         return 0;
749 }
750
751 static void joydev_remove_chrdev(struct joydev *joydev)
752 {
753         mutex_lock(&joydev_table_mutex);
754         joydev_table[joydev->minor] = NULL;
755         mutex_unlock(&joydev_table_mutex);
756 }
757
758 /*
759  * Mark device non-existant. This disables writes, ioctls and
760  * prevents new users from opening the device. Already posted
761  * blocking reads will stay, however new ones will fail.
762  */
763 static void joydev_mark_dead(struct joydev *joydev)
764 {
765         mutex_lock(&joydev->mutex);
766         joydev->exist = false;
767         mutex_unlock(&joydev->mutex);
768 }
769
770 static void joydev_cleanup(struct joydev *joydev)
771 {
772         struct input_handle *handle = &joydev->handle;
773
774         joydev_mark_dead(joydev);
775         joydev_hangup(joydev);
776         joydev_remove_chrdev(joydev);
777
778         /* joydev is marked dead so noone else accesses joydev->open */
779         if (joydev->open)
780                 input_close_device(handle);
781 }
782
783
784 static bool joydev_match(struct input_handler *handler, struct input_dev *dev)
785 {
786         /* Avoid touchpads and touchscreens */
787         if (test_bit(EV_KEY, dev->evbit) && test_bit(BTN_TOUCH, dev->keybit))
788                 return false;
789
790         /* Avoid tablets, digitisers and similar devices */
791         if (test_bit(EV_KEY, dev->evbit) && test_bit(BTN_DIGI, dev->keybit))
792                 return false;
793
794         return true;
795 }
796
797 static int joydev_connect(struct input_handler *handler, struct input_dev *dev,
798                           const struct input_device_id *id)
799 {
800         struct joydev *joydev;
801         int i, j, t, minor;
802         int error;
803
804         for (minor = 0; minor < JOYDEV_MINORS; minor++)
805                 if (!joydev_table[minor])
806                         break;
807
808         if (minor == JOYDEV_MINORS) {
809                 printk(KERN_ERR "joydev: no more free joydev devices\n");
810                 return -ENFILE;
811         }
812
813         joydev = kzalloc(sizeof(struct joydev), GFP_KERNEL);
814         if (!joydev)
815                 return -ENOMEM;
816
817         INIT_LIST_HEAD(&joydev->client_list);
818         spin_lock_init(&joydev->client_lock);
819         mutex_init(&joydev->mutex);
820         init_waitqueue_head(&joydev->wait);
821
822         dev_set_name(&joydev->dev, "js%d", minor);
823         joydev->exist = true;
824         joydev->minor = minor;
825
826         joydev->handle.dev = input_get_device(dev);
827         joydev->handle.name = dev_name(&joydev->dev);
828         joydev->handle.handler = handler;
829         joydev->handle.private = joydev;
830
831         for (i = 0; i < ABS_CNT; i++)
832                 if (test_bit(i, dev->absbit)) {
833                         joydev->absmap[i] = joydev->nabs;
834                         joydev->abspam[joydev->nabs] = i;
835                         joydev->nabs++;
836                 }
837
838         for (i = BTN_JOYSTICK - BTN_MISC; i < KEY_MAX - BTN_MISC + 1; i++)
839                 if (test_bit(i + BTN_MISC, dev->keybit)) {
840                         joydev->keymap[i] = joydev->nkey;
841                         joydev->keypam[joydev->nkey] = i + BTN_MISC;
842                         joydev->nkey++;
843                 }
844
845         for (i = 0; i < BTN_JOYSTICK - BTN_MISC; i++)
846                 if (test_bit(i + BTN_MISC, dev->keybit)) {
847                         joydev->keymap[i] = joydev->nkey;
848                         joydev->keypam[joydev->nkey] = i + BTN_MISC;
849                         joydev->nkey++;
850                 }
851
852         for (i = 0; i < joydev->nabs; i++) {
853                 j = joydev->abspam[i];
854                 if (input_abs_get_max(dev, j) == input_abs_get_min(dev, j)) {
855                         joydev->corr[i].type = JS_CORR_NONE;
856                         joydev->abs[i] = input_abs_get_val(dev, j);
857                         continue;
858                 }
859                 joydev->corr[i].type = JS_CORR_BROKEN;
860                 joydev->corr[i].prec = input_abs_get_fuzz(dev, j);
861
862                 t = (input_abs_get_max(dev, j) + input_abs_get_min(dev, j)) / 2;
863                 joydev->corr[i].coef[0] = t - input_abs_get_flat(dev, j);
864                 joydev->corr[i].coef[1] = t + input_abs_get_flat(dev, j);
865
866                 t = (input_abs_get_max(dev, j) - input_abs_get_min(dev, j)) / 2
867                         - 2 * input_abs_get_flat(dev, j);
868                 if (t) {
869                         joydev->corr[i].coef[2] = (1 << 29) / t;
870                         joydev->corr[i].coef[3] = (1 << 29) / t;
871
872                         joydev->abs[i] =
873                                 joydev_correct(input_abs_get_val(dev, j),
874                                                joydev->corr + i);
875                 }
876         }
877
878         joydev->dev.devt = MKDEV(INPUT_MAJOR, JOYDEV_MINOR_BASE + minor);
879         joydev->dev.class = &input_class;
880         joydev->dev.parent = &dev->dev;
881         joydev->dev.release = joydev_free;
882         device_initialize(&joydev->dev);
883
884         error = input_register_handle(&joydev->handle);
885         if (error)
886                 goto err_free_joydev;
887
888         error = joydev_install_chrdev(joydev);
889         if (error)
890                 goto err_unregister_handle;
891
892         error = device_add(&joydev->dev);
893         if (error)
894                 goto err_cleanup_joydev;
895
896         return 0;
897
898  err_cleanup_joydev:
899         joydev_cleanup(joydev);
900  err_unregister_handle:
901         input_unregister_handle(&joydev->handle);
902  err_free_joydev:
903         put_device(&joydev->dev);
904         return error;
905 }
906
907 static void joydev_disconnect(struct input_handle *handle)
908 {
909         struct joydev *joydev = handle->private;
910
911         device_del(&joydev->dev);
912         joydev_cleanup(joydev);
913         input_unregister_handle(handle);
914         put_device(&joydev->dev);
915 }
916
917 static const struct input_device_id joydev_ids[] = {
918         {
919                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
920                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
921                 .evbit = { BIT_MASK(EV_ABS) },
922                 .absbit = { BIT_MASK(ABS_X) },
923         },
924         {
925                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
926                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
927                 .evbit = { BIT_MASK(EV_ABS) },
928                 .absbit = { BIT_MASK(ABS_WHEEL) },
929         },
930         {
931                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
932                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
933                 .evbit = { BIT_MASK(EV_ABS) },
934                 .absbit = { BIT_MASK(ABS_THROTTLE) },
935         },
936         {
937                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
938                                 INPUT_DEVICE_ID_MATCH_KEYBIT,
939                 .evbit = { BIT_MASK(EV_KEY) },
940                 .keybit = {[BIT_WORD(BTN_JOYSTICK)] = BIT_MASK(BTN_JOYSTICK) },
941         },
942         {
943                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
944                                 INPUT_DEVICE_ID_MATCH_KEYBIT,
945                 .evbit = { BIT_MASK(EV_KEY) },
946                 .keybit = { [BIT_WORD(BTN_GAMEPAD)] = BIT_MASK(BTN_GAMEPAD) },
947         },
948         {
949                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
950                                 INPUT_DEVICE_ID_MATCH_KEYBIT,
951                 .evbit = { BIT_MASK(EV_KEY) },
952                 .keybit = { [BIT_WORD(BTN_TRIGGER_HAPPY)] = BIT_MASK(BTN_TRIGGER_HAPPY) },
953         },
954         { }     /* Terminating entry */
955 };
956
957 MODULE_DEVICE_TABLE(input, joydev_ids);
958
959 static struct input_handler joydev_handler = {
960         .event          = joydev_event,
961         .match          = joydev_match,
962         .connect        = joydev_connect,
963         .disconnect     = joydev_disconnect,
964         .fops           = &joydev_fops,
965         .minor          = JOYDEV_MINOR_BASE,
966         .name           = "joydev",
967         .id_table       = joydev_ids,
968 };
969
970 static int __init joydev_init(void)
971 {
972         return input_register_handler(&joydev_handler);
973 }
974
975 static void __exit joydev_exit(void)
976 {
977         input_unregister_handler(&joydev_handler);
978 }
979
980 module_init(joydev_init);
981 module_exit(joydev_exit);