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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14
15 #include <asm/io.h>
16 #include <linux/delay.h>
17 #include <linux/errno.h>
18 #include <linux/joystick.h>
19 #include <linux/input.h>
20 #include <linux/kernel.h>
21 #include <linux/major.h>
22 #include <linux/sched.h>
23 #include <linux/slab.h>
24 #include <linux/mm.h>
25 #include <linux/miscdevice.h>
26 #include <linux/module.h>
27 #include <linux/poll.h>
28 #include <linux/init.h>
29 #include <linux/device.h>
30 #include <linux/cdev.h>
31
32 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
33 MODULE_DESCRIPTION("Joystick device interfaces");
34 MODULE_SUPPORTED_DEVICE("input/js");
35 MODULE_LICENSE("GPL");
36
37 #define JOYDEV_MINOR_BASE 0
38 #define JOYDEV_MINORS 16
39 #define JOYDEV_BUFFER_SIZE 64
40
41 struct joydev {
42 int open;
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 struct cdev cdev;
50 bool exist;
51
52 struct js_corr corr[ABS_CNT];
53 struct JS_DATA_SAVE_TYPE glue;
54 int nabs;
55 int nkey;
56 __u16 keymap[KEY_MAX - BTN_MISC + 1];
57 __u16 keypam[KEY_MAX - BTN_MISC + 1];
58 __u8 absmap[ABS_CNT];
59 __u8 abspam[ABS_CNT];
60 __s16 abs[ABS_CNT];
61 };
62
63 struct joydev_client {
64 struct js_event buffer[JOYDEV_BUFFER_SIZE];
65 int head;
66 int tail;
67 int startup;
68 spinlock_t buffer_lock; /* protects access to buffer, head and tail */
69 struct fasync_struct *fasync;
70 struct joydev *joydev;
71 struct list_head node;
72 };
73
joydev_correct(int value,struct js_corr * corr)74 static int joydev_correct(int value, struct js_corr *corr)
75 {
76 switch (corr->type) {
77
78 case JS_CORR_NONE:
79 break;
80
81 case JS_CORR_BROKEN:
82 value = value > corr->coef[0] ? (value < corr->coef[1] ? 0 :
83 ((corr->coef[3] * (value - corr->coef[1])) >> 14)) :
84 ((corr->coef[2] * (value - corr->coef[0])) >> 14);
85 break;
86
87 default:
88 return 0;
89 }
90
91 return value < -32767 ? -32767 : (value > 32767 ? 32767 : value);
92 }
93
joydev_pass_event(struct joydev_client * client,struct js_event * event)94 static void joydev_pass_event(struct joydev_client *client,
95 struct js_event *event)
96 {
97 struct joydev *joydev = client->joydev;
98
99 /*
100 * IRQs already disabled, just acquire the lock
101 */
102 spin_lock(&client->buffer_lock);
103
104 client->buffer[client->head] = *event;
105
106 if (client->startup == joydev->nabs + joydev->nkey) {
107 client->head++;
108 client->head &= JOYDEV_BUFFER_SIZE - 1;
109 if (client->tail == client->head)
110 client->startup = 0;
111 }
112
113 spin_unlock(&client->buffer_lock);
114
115 kill_fasync(&client->fasync, SIGIO, POLL_IN);
116 }
117
joydev_event(struct input_handle * handle,unsigned int type,unsigned int code,int value)118 static void joydev_event(struct input_handle *handle,
119 unsigned int type, unsigned int code, int value)
120 {
121 struct joydev *joydev = handle->private;
122 struct joydev_client *client;
123 struct js_event event;
124
125 switch (type) {
126
127 case EV_KEY:
128 if (code < BTN_MISC || value == 2)
129 return;
130 event.type = JS_EVENT_BUTTON;
131 event.number = joydev->keymap[code - BTN_MISC];
132 event.value = value;
133 break;
134
135 case EV_ABS:
136 event.type = JS_EVENT_AXIS;
137 event.number = joydev->absmap[code];
138 event.value = joydev_correct(value,
139 &joydev->corr[event.number]);
140 if (event.value == joydev->abs[event.number])
141 return;
142 joydev->abs[event.number] = event.value;
143 break;
144
145 default:
146 return;
147 }
148
149 event.time = jiffies_to_msecs(jiffies);
150
151 rcu_read_lock();
152 list_for_each_entry_rcu(client, &joydev->client_list, node)
153 joydev_pass_event(client, &event);
154 rcu_read_unlock();
155
156 wake_up_interruptible(&joydev->wait);
157 }
158
joydev_fasync(int fd,struct file * file,int on)159 static int joydev_fasync(int fd, struct file *file, int on)
160 {
161 struct joydev_client *client = file->private_data;
162
163 return fasync_helper(fd, file, on, &client->fasync);
164 }
165
joydev_free(struct device * dev)166 static void joydev_free(struct device *dev)
167 {
168 struct joydev *joydev = container_of(dev, struct joydev, dev);
169
170 input_put_device(joydev->handle.dev);
171 kfree(joydev);
172 }
173
joydev_attach_client(struct joydev * joydev,struct joydev_client * client)174 static void joydev_attach_client(struct joydev *joydev,
175 struct joydev_client *client)
176 {
177 spin_lock(&joydev->client_lock);
178 list_add_tail_rcu(&client->node, &joydev->client_list);
179 spin_unlock(&joydev->client_lock);
180 }
181
joydev_detach_client(struct joydev * joydev,struct joydev_client * client)182 static void joydev_detach_client(struct joydev *joydev,
183 struct joydev_client *client)
184 {
185 spin_lock(&joydev->client_lock);
186 list_del_rcu(&client->node);
187 spin_unlock(&joydev->client_lock);
188 synchronize_rcu();
189 }
190
joydev_open_device(struct joydev * joydev)191 static int joydev_open_device(struct joydev *joydev)
192 {
193 int retval;
194
195 retval = mutex_lock_interruptible(&joydev->mutex);
196 if (retval)
197 return retval;
198
199 if (!joydev->exist)
200 retval = -ENODEV;
201 else if (!joydev->open++) {
202 retval = input_open_device(&joydev->handle);
203 if (retval)
204 joydev->open--;
205 }
206
207 mutex_unlock(&joydev->mutex);
208 return retval;
209 }
210
joydev_close_device(struct joydev * joydev)211 static void joydev_close_device(struct joydev *joydev)
212 {
213 mutex_lock(&joydev->mutex);
214
215 if (joydev->exist && !--joydev->open)
216 input_close_device(&joydev->handle);
217
218 mutex_unlock(&joydev->mutex);
219 }
220
221 /*
222 * Wake up users waiting for IO so they can disconnect from
223 * dead device.
224 */
joydev_hangup(struct joydev * joydev)225 static void joydev_hangup(struct joydev *joydev)
226 {
227 struct joydev_client *client;
228
229 spin_lock(&joydev->client_lock);
230 list_for_each_entry(client, &joydev->client_list, node)
231 kill_fasync(&client->fasync, SIGIO, POLL_HUP);
232 spin_unlock(&joydev->client_lock);
233
234 wake_up_interruptible(&joydev->wait);
235 }
236
joydev_release(struct inode * inode,struct file * file)237 static int joydev_release(struct inode *inode, struct file *file)
238 {
239 struct joydev_client *client = file->private_data;
240 struct joydev *joydev = client->joydev;
241
242 joydev_detach_client(joydev, client);
243 kfree(client);
244
245 joydev_close_device(joydev);
246
247 return 0;
248 }
249
joydev_open(struct inode * inode,struct file * file)250 static int joydev_open(struct inode *inode, struct file *file)
251 {
252 struct joydev *joydev =
253 container_of(inode->i_cdev, struct joydev, cdev);
254 struct joydev_client *client;
255 int error;
256
257 client = kzalloc(sizeof(struct joydev_client), GFP_KERNEL);
258 if (!client)
259 return -ENOMEM;
260
261 spin_lock_init(&client->buffer_lock);
262 client->joydev = joydev;
263 joydev_attach_client(joydev, client);
264
265 error = joydev_open_device(joydev);
266 if (error)
267 goto err_free_client;
268
269 file->private_data = client;
270 nonseekable_open(inode, file);
271
272 return 0;
273
274 err_free_client:
275 joydev_detach_client(joydev, client);
276 kfree(client);
277 return error;
278 }
279
joydev_generate_startup_event(struct joydev_client * client,struct input_dev * input,struct js_event * event)280 static int joydev_generate_startup_event(struct joydev_client *client,
281 struct input_dev *input,
282 struct js_event *event)
283 {
284 struct joydev *joydev = client->joydev;
285 int have_event;
286
287 spin_lock_irq(&client->buffer_lock);
288
289 have_event = client->startup < joydev->nabs + joydev->nkey;
290
291 if (have_event) {
292
293 event->time = jiffies_to_msecs(jiffies);
294 if (client->startup < joydev->nkey) {
295 event->type = JS_EVENT_BUTTON | JS_EVENT_INIT;
296 event->number = client->startup;
297 event->value = !!test_bit(joydev->keypam[event->number],
298 input->key);
299 } else {
300 event->type = JS_EVENT_AXIS | JS_EVENT_INIT;
301 event->number = client->startup - joydev->nkey;
302 event->value = joydev->abs[event->number];
303 }
304 client->startup++;
305 }
306
307 spin_unlock_irq(&client->buffer_lock);
308
309 return have_event;
310 }
311
joydev_fetch_next_event(struct joydev_client * client,struct js_event * event)312 static int joydev_fetch_next_event(struct joydev_client *client,
313 struct js_event *event)
314 {
315 int have_event;
316
317 spin_lock_irq(&client->buffer_lock);
318
319 have_event = client->head != client->tail;
320 if (have_event) {
321 *event = client->buffer[client->tail++];
322 client->tail &= JOYDEV_BUFFER_SIZE - 1;
323 }
324
325 spin_unlock_irq(&client->buffer_lock);
326
327 return have_event;
328 }
329
330 /*
331 * Old joystick interface
332 */
joydev_0x_read(struct joydev_client * client,struct input_dev * input,char __user * buf)333 static ssize_t joydev_0x_read(struct joydev_client *client,
334 struct input_dev *input,
335 char __user *buf)
336 {
337 struct joydev *joydev = client->joydev;
338 struct JS_DATA_TYPE data;
339 int i;
340
341 spin_lock_irq(&input->event_lock);
342
343 /*
344 * Get device state
345 */
346 for (data.buttons = i = 0; i < 32 && i < joydev->nkey; i++)
347 data.buttons |=
348 test_bit(joydev->keypam[i], input->key) ? (1 << i) : 0;
349 data.x = (joydev->abs[0] / 256 + 128) >> joydev->glue.JS_CORR.x;
350 data.y = (joydev->abs[1] / 256 + 128) >> joydev->glue.JS_CORR.y;
351
352 /*
353 * Reset reader's event queue
354 */
355 spin_lock(&client->buffer_lock);
356 client->startup = 0;
357 client->tail = client->head;
358 spin_unlock(&client->buffer_lock);
359
360 spin_unlock_irq(&input->event_lock);
361
362 if (copy_to_user(buf, &data, sizeof(struct JS_DATA_TYPE)))
363 return -EFAULT;
364
365 return sizeof(struct JS_DATA_TYPE);
366 }
367
joydev_data_pending(struct joydev_client * client)368 static inline int joydev_data_pending(struct joydev_client *client)
369 {
370 struct joydev *joydev = client->joydev;
371
372 return client->startup < joydev->nabs + joydev->nkey ||
373 client->head != client->tail;
374 }
375
joydev_read(struct file * file,char __user * buf,size_t count,loff_t * ppos)376 static ssize_t joydev_read(struct file *file, char __user *buf,
377 size_t count, loff_t *ppos)
378 {
379 struct joydev_client *client = file->private_data;
380 struct joydev *joydev = client->joydev;
381 struct input_dev *input = joydev->handle.dev;
382 struct js_event event;
383 int retval;
384
385 if (!joydev->exist)
386 return -ENODEV;
387
388 if (count < sizeof(struct js_event))
389 return -EINVAL;
390
391 if (count == sizeof(struct JS_DATA_TYPE))
392 return joydev_0x_read(client, input, buf);
393
394 if (!joydev_data_pending(client) && (file->f_flags & O_NONBLOCK))
395 return -EAGAIN;
396
397 retval = wait_event_interruptible(joydev->wait,
398 !joydev->exist || joydev_data_pending(client));
399 if (retval)
400 return retval;
401
402 if (!joydev->exist)
403 return -ENODEV;
404
405 while (retval + sizeof(struct js_event) <= count &&
406 joydev_generate_startup_event(client, input, &event)) {
407
408 if (copy_to_user(buf + retval, &event, sizeof(struct js_event)))
409 return -EFAULT;
410
411 retval += sizeof(struct js_event);
412 }
413
414 while (retval + sizeof(struct js_event) <= count &&
415 joydev_fetch_next_event(client, &event)) {
416
417 if (copy_to_user(buf + retval, &event, sizeof(struct js_event)))
418 return -EFAULT;
419
420 retval += sizeof(struct js_event);
421 }
422
423 return retval;
424 }
425
426 /* No kernel lock - fine */
joydev_poll(struct file * file,poll_table * wait)427 static unsigned int joydev_poll(struct file *file, poll_table *wait)
428 {
429 struct joydev_client *client = file->private_data;
430 struct joydev *joydev = client->joydev;
431
432 poll_wait(file, &joydev->wait, wait);
433 return (joydev_data_pending(client) ? (POLLIN | POLLRDNORM) : 0) |
434 (joydev->exist ? 0 : (POLLHUP | POLLERR));
435 }
436
joydev_handle_JSIOCSAXMAP(struct joydev * joydev,void __user * argp,size_t len)437 static int joydev_handle_JSIOCSAXMAP(struct joydev *joydev,
438 void __user *argp, size_t len)
439 {
440 __u8 *abspam;
441 int i;
442 int retval = 0;
443
444 len = min(len, sizeof(joydev->abspam));
445
446 /* Validate the map. */
447 abspam = memdup_user(argp, len);
448 if (IS_ERR(abspam))
449 return PTR_ERR(abspam);
450
451 for (i = 0; i < len && i < joydev->nabs; i++) {
452 if (abspam[i] > ABS_MAX) {
453 retval = -EINVAL;
454 goto out;
455 }
456 }
457
458 memcpy(joydev->abspam, abspam, len);
459
460 for (i = 0; i < joydev->nabs; i++)
461 joydev->absmap[joydev->abspam[i]] = i;
462
463 out:
464 kfree(abspam);
465 return retval;
466 }
467
joydev_handle_JSIOCSBTNMAP(struct joydev * joydev,void __user * argp,size_t len)468 static int joydev_handle_JSIOCSBTNMAP(struct joydev *joydev,
469 void __user *argp, size_t len)
470 {
471 __u16 *keypam;
472 int i;
473 int retval = 0;
474
475 if (len % sizeof(*keypam))
476 return -EINVAL;
477
478 len = min(len, sizeof(joydev->keypam));
479
480 /* Validate the map. */
481 keypam = memdup_user(argp, len);
482 if (IS_ERR(keypam))
483 return PTR_ERR(keypam);
484
485 for (i = 0; i < (len / 2) && i < joydev->nkey; i++) {
486 if (keypam[i] > KEY_MAX || keypam[i] < BTN_MISC) {
487 retval = -EINVAL;
488 goto out;
489 }
490 }
491
492 memcpy(joydev->keypam, keypam, len);
493
494 for (i = 0; i < joydev->nkey; i++)
495 joydev->keymap[joydev->keypam[i] - BTN_MISC] = i;
496
497 out:
498 kfree(keypam);
499 return retval;
500 }
501
502
joydev_ioctl_common(struct joydev * joydev,unsigned int cmd,void __user * argp)503 static int joydev_ioctl_common(struct joydev *joydev,
504 unsigned int cmd, void __user *argp)
505 {
506 struct input_dev *dev = joydev->handle.dev;
507 size_t len;
508 int i;
509 const char *name;
510
511 /* Process fixed-sized commands. */
512 switch (cmd) {
513
514 case JS_SET_CAL:
515 return copy_from_user(&joydev->glue.JS_CORR, argp,
516 sizeof(joydev->glue.JS_CORR)) ? -EFAULT : 0;
517
518 case JS_GET_CAL:
519 return copy_to_user(argp, &joydev->glue.JS_CORR,
520 sizeof(joydev->glue.JS_CORR)) ? -EFAULT : 0;
521
522 case JS_SET_TIMEOUT:
523 return get_user(joydev->glue.JS_TIMEOUT, (s32 __user *) argp);
524
525 case JS_GET_TIMEOUT:
526 return put_user(joydev->glue.JS_TIMEOUT, (s32 __user *) argp);
527
528 case JSIOCGVERSION:
529 return put_user(JS_VERSION, (__u32 __user *) argp);
530
531 case JSIOCGAXES:
532 return put_user(joydev->nabs, (__u8 __user *) argp);
533
534 case JSIOCGBUTTONS:
535 return put_user(joydev->nkey, (__u8 __user *) argp);
536
537 case JSIOCSCORR:
538 if (copy_from_user(joydev->corr, argp,
539 sizeof(joydev->corr[0]) * joydev->nabs))
540 return -EFAULT;
541
542 for (i = 0; i < joydev->nabs; i++) {
543 int val = input_abs_get_val(dev, joydev->abspam[i]);
544 joydev->abs[i] = joydev_correct(val, &joydev->corr[i]);
545 }
546 return 0;
547
548 case JSIOCGCORR:
549 return copy_to_user(argp, joydev->corr,
550 sizeof(joydev->corr[0]) * joydev->nabs) ? -EFAULT : 0;
551
552 }
553
554 /*
555 * Process variable-sized commands (the axis and button map commands
556 * are considered variable-sized to decouple them from the values of
557 * ABS_MAX and KEY_MAX).
558 */
559 switch (cmd & ~IOCSIZE_MASK) {
560
561 case (JSIOCSAXMAP & ~IOCSIZE_MASK):
562 return joydev_handle_JSIOCSAXMAP(joydev, argp, _IOC_SIZE(cmd));
563
564 case (JSIOCGAXMAP & ~IOCSIZE_MASK):
565 len = min_t(size_t, _IOC_SIZE(cmd), sizeof(joydev->abspam));
566 return copy_to_user(argp, joydev->abspam, len) ? -EFAULT : len;
567
568 case (JSIOCSBTNMAP & ~IOCSIZE_MASK):
569 return joydev_handle_JSIOCSBTNMAP(joydev, argp, _IOC_SIZE(cmd));
570
571 case (JSIOCGBTNMAP & ~IOCSIZE_MASK):
572 len = min_t(size_t, _IOC_SIZE(cmd), sizeof(joydev->keypam));
573 return copy_to_user(argp, joydev->keypam, len) ? -EFAULT : len;
574
575 case JSIOCGNAME(0):
576 name = dev->name;
577 if (!name)
578 return 0;
579
580 len = min_t(size_t, _IOC_SIZE(cmd), strlen(name) + 1);
581 return copy_to_user(argp, name, len) ? -EFAULT : len;
582 }
583
584 return -EINVAL;
585 }
586
587 #ifdef CONFIG_COMPAT
joydev_compat_ioctl(struct file * file,unsigned int cmd,unsigned long arg)588 static long joydev_compat_ioctl(struct file *file,
589 unsigned int cmd, unsigned long arg)
590 {
591 struct joydev_client *client = file->private_data;
592 struct joydev *joydev = client->joydev;
593 void __user *argp = (void __user *)arg;
594 s32 tmp32;
595 struct JS_DATA_SAVE_TYPE_32 ds32;
596 int retval;
597
598 retval = mutex_lock_interruptible(&joydev->mutex);
599 if (retval)
600 return retval;
601
602 if (!joydev->exist) {
603 retval = -ENODEV;
604 goto out;
605 }
606
607 switch (cmd) {
608
609 case JS_SET_TIMELIMIT:
610 retval = get_user(tmp32, (s32 __user *) arg);
611 if (retval == 0)
612 joydev->glue.JS_TIMELIMIT = tmp32;
613 break;
614
615 case JS_GET_TIMELIMIT:
616 tmp32 = joydev->glue.JS_TIMELIMIT;
617 retval = put_user(tmp32, (s32 __user *) arg);
618 break;
619
620 case JS_SET_ALL:
621 retval = copy_from_user(&ds32, argp,
622 sizeof(ds32)) ? -EFAULT : 0;
623 if (retval == 0) {
624 joydev->glue.JS_TIMEOUT = ds32.JS_TIMEOUT;
625 joydev->glue.BUSY = ds32.BUSY;
626 joydev->glue.JS_EXPIRETIME = ds32.JS_EXPIRETIME;
627 joydev->glue.JS_TIMELIMIT = ds32.JS_TIMELIMIT;
628 joydev->glue.JS_SAVE = ds32.JS_SAVE;
629 joydev->glue.JS_CORR = ds32.JS_CORR;
630 }
631 break;
632
633 case JS_GET_ALL:
634 ds32.JS_TIMEOUT = joydev->glue.JS_TIMEOUT;
635 ds32.BUSY = joydev->glue.BUSY;
636 ds32.JS_EXPIRETIME = joydev->glue.JS_EXPIRETIME;
637 ds32.JS_TIMELIMIT = joydev->glue.JS_TIMELIMIT;
638 ds32.JS_SAVE = joydev->glue.JS_SAVE;
639 ds32.JS_CORR = joydev->glue.JS_CORR;
640
641 retval = copy_to_user(argp, &ds32, sizeof(ds32)) ? -EFAULT : 0;
642 break;
643
644 default:
645 retval = joydev_ioctl_common(joydev, cmd, argp);
646 break;
647 }
648
649 out:
650 mutex_unlock(&joydev->mutex);
651 return retval;
652 }
653 #endif /* CONFIG_COMPAT */
654
joydev_ioctl(struct file * file,unsigned int cmd,unsigned long arg)655 static long joydev_ioctl(struct file *file,
656 unsigned int cmd, unsigned long arg)
657 {
658 struct joydev_client *client = file->private_data;
659 struct joydev *joydev = client->joydev;
660 void __user *argp = (void __user *)arg;
661 int retval;
662
663 retval = mutex_lock_interruptible(&joydev->mutex);
664 if (retval)
665 return retval;
666
667 if (!joydev->exist) {
668 retval = -ENODEV;
669 goto out;
670 }
671
672 switch (cmd) {
673
674 case JS_SET_TIMELIMIT:
675 retval = get_user(joydev->glue.JS_TIMELIMIT,
676 (long __user *) arg);
677 break;
678
679 case JS_GET_TIMELIMIT:
680 retval = put_user(joydev->glue.JS_TIMELIMIT,
681 (long __user *) arg);
682 break;
683
684 case JS_SET_ALL:
685 retval = copy_from_user(&joydev->glue, argp,
686 sizeof(joydev->glue)) ? -EFAULT : 0;
687 break;
688
689 case JS_GET_ALL:
690 retval = copy_to_user(argp, &joydev->glue,
691 sizeof(joydev->glue)) ? -EFAULT : 0;
692 break;
693
694 default:
695 retval = joydev_ioctl_common(joydev, cmd, argp);
696 break;
697 }
698 out:
699 mutex_unlock(&joydev->mutex);
700 return retval;
701 }
702
703 static const struct file_operations joydev_fops = {
704 .owner = THIS_MODULE,
705 .read = joydev_read,
706 .poll = joydev_poll,
707 .open = joydev_open,
708 .release = joydev_release,
709 .unlocked_ioctl = joydev_ioctl,
710 #ifdef CONFIG_COMPAT
711 .compat_ioctl = joydev_compat_ioctl,
712 #endif
713 .fasync = joydev_fasync,
714 .llseek = no_llseek,
715 };
716
717 /*
718 * Mark device non-existent. This disables writes, ioctls and
719 * prevents new users from opening the device. Already posted
720 * blocking reads will stay, however new ones will fail.
721 */
joydev_mark_dead(struct joydev * joydev)722 static void joydev_mark_dead(struct joydev *joydev)
723 {
724 mutex_lock(&joydev->mutex);
725 joydev->exist = false;
726 mutex_unlock(&joydev->mutex);
727 }
728
joydev_cleanup(struct joydev * joydev)729 static void joydev_cleanup(struct joydev *joydev)
730 {
731 struct input_handle *handle = &joydev->handle;
732
733 joydev_mark_dead(joydev);
734 joydev_hangup(joydev);
735
736 cdev_del(&joydev->cdev);
737
738 /* joydev is marked dead so no one else accesses joydev->open */
739 if (joydev->open)
740 input_close_device(handle);
741 }
742
joydev_dev_is_absolute_mouse(struct input_dev * dev)743 static bool joydev_dev_is_absolute_mouse(struct input_dev *dev)
744 {
745 DECLARE_BITMAP(jd_scratch, KEY_CNT);
746
747 BUILD_BUG_ON(ABS_CNT > KEY_CNT || EV_CNT > KEY_CNT);
748
749 /*
750 * Virtualization (VMware, etc) and remote management (HP
751 * ILO2) solutions use absolute coordinates for their virtual
752 * pointing devices so that there is one-to-one relationship
753 * between pointer position on the host screen and virtual
754 * guest screen, and so their mice use ABS_X, ABS_Y and 3
755 * primary button events. This clashes with what joydev
756 * considers to be joysticks (a device with at minimum ABS_X
757 * axis).
758 *
759 * Here we are trying to separate absolute mice from
760 * joysticks. A device is, for joystick detection purposes,
761 * considered to be an absolute mouse if the following is
762 * true:
763 *
764 * 1) Event types are exactly EV_ABS, EV_KEY and EV_SYN.
765 * 2) Absolute events are exactly ABS_X and ABS_Y.
766 * 3) Keys are exactly BTN_LEFT, BTN_RIGHT and BTN_MIDDLE.
767 * 4) Device is not on "Amiga" bus.
768 */
769
770 bitmap_zero(jd_scratch, EV_CNT);
771 __set_bit(EV_ABS, jd_scratch);
772 __set_bit(EV_KEY, jd_scratch);
773 __set_bit(EV_SYN, jd_scratch);
774 if (!bitmap_equal(jd_scratch, dev->evbit, EV_CNT))
775 return false;
776
777 bitmap_zero(jd_scratch, ABS_CNT);
778 __set_bit(ABS_X, jd_scratch);
779 __set_bit(ABS_Y, jd_scratch);
780 if (!bitmap_equal(dev->absbit, jd_scratch, ABS_CNT))
781 return false;
782
783 bitmap_zero(jd_scratch, KEY_CNT);
784 __set_bit(BTN_LEFT, jd_scratch);
785 __set_bit(BTN_RIGHT, jd_scratch);
786 __set_bit(BTN_MIDDLE, jd_scratch);
787
788 if (!bitmap_equal(dev->keybit, jd_scratch, KEY_CNT))
789 return false;
790
791 /*
792 * Amiga joystick (amijoy) historically uses left/middle/right
793 * button events.
794 */
795 if (dev->id.bustype == BUS_AMIGA)
796 return false;
797
798 return true;
799 }
800
joydev_match(struct input_handler * handler,struct input_dev * dev)801 static bool joydev_match(struct input_handler *handler, struct input_dev *dev)
802 {
803 /* Avoid touchpads and touchscreens */
804 if (test_bit(EV_KEY, dev->evbit) && test_bit(BTN_TOUCH, dev->keybit))
805 return false;
806
807 /* Avoid tablets, digitisers and similar devices */
808 if (test_bit(EV_KEY, dev->evbit) && test_bit(BTN_DIGI, dev->keybit))
809 return false;
810
811 /* Avoid absolute mice */
812 if (joydev_dev_is_absolute_mouse(dev))
813 return false;
814
815 return true;
816 }
817
joydev_connect(struct input_handler * handler,struct input_dev * dev,const struct input_device_id * id)818 static int joydev_connect(struct input_handler *handler, struct input_dev *dev,
819 const struct input_device_id *id)
820 {
821 struct joydev *joydev;
822 int i, j, t, minor, dev_no;
823 int error;
824
825 minor = input_get_new_minor(JOYDEV_MINOR_BASE, JOYDEV_MINORS, true);
826 if (minor < 0) {
827 error = minor;
828 pr_err("failed to reserve new minor: %d\n", error);
829 return error;
830 }
831
832 joydev = kzalloc(sizeof(struct joydev), GFP_KERNEL);
833 if (!joydev) {
834 error = -ENOMEM;
835 goto err_free_minor;
836 }
837
838 INIT_LIST_HEAD(&joydev->client_list);
839 spin_lock_init(&joydev->client_lock);
840 mutex_init(&joydev->mutex);
841 init_waitqueue_head(&joydev->wait);
842 joydev->exist = true;
843
844 dev_no = minor;
845 /* Normalize device number if it falls into legacy range */
846 if (dev_no < JOYDEV_MINOR_BASE + JOYDEV_MINORS)
847 dev_no -= JOYDEV_MINOR_BASE;
848 dev_set_name(&joydev->dev, "js%d", dev_no);
849
850 joydev->handle.dev = input_get_device(dev);
851 joydev->handle.name = dev_name(&joydev->dev);
852 joydev->handle.handler = handler;
853 joydev->handle.private = joydev;
854
855 for_each_set_bit(i, dev->absbit, ABS_CNT) {
856 joydev->absmap[i] = joydev->nabs;
857 joydev->abspam[joydev->nabs] = i;
858 joydev->nabs++;
859 }
860
861 for (i = BTN_JOYSTICK - BTN_MISC; i < KEY_MAX - BTN_MISC + 1; i++)
862 if (test_bit(i + BTN_MISC, dev->keybit)) {
863 joydev->keymap[i] = joydev->nkey;
864 joydev->keypam[joydev->nkey] = i + BTN_MISC;
865 joydev->nkey++;
866 }
867
868 for (i = 0; i < BTN_JOYSTICK - BTN_MISC; i++)
869 if (test_bit(i + BTN_MISC, dev->keybit)) {
870 joydev->keymap[i] = joydev->nkey;
871 joydev->keypam[joydev->nkey] = i + BTN_MISC;
872 joydev->nkey++;
873 }
874
875 for (i = 0; i < joydev->nabs; i++) {
876 j = joydev->abspam[i];
877 if (input_abs_get_max(dev, j) == input_abs_get_min(dev, j)) {
878 joydev->corr[i].type = JS_CORR_NONE;
879 joydev->abs[i] = input_abs_get_val(dev, j);
880 continue;
881 }
882 joydev->corr[i].type = JS_CORR_BROKEN;
883 joydev->corr[i].prec = input_abs_get_fuzz(dev, j);
884
885 t = (input_abs_get_max(dev, j) + input_abs_get_min(dev, j)) / 2;
886 joydev->corr[i].coef[0] = t - input_abs_get_flat(dev, j);
887 joydev->corr[i].coef[1] = t + input_abs_get_flat(dev, j);
888
889 t = (input_abs_get_max(dev, j) - input_abs_get_min(dev, j)) / 2
890 - 2 * input_abs_get_flat(dev, j);
891 if (t) {
892 joydev->corr[i].coef[2] = (1 << 29) / t;
893 joydev->corr[i].coef[3] = (1 << 29) / t;
894
895 joydev->abs[i] =
896 joydev_correct(input_abs_get_val(dev, j),
897 joydev->corr + i);
898 }
899 }
900
901 joydev->dev.devt = MKDEV(INPUT_MAJOR, minor);
902 joydev->dev.class = &input_class;
903 joydev->dev.parent = &dev->dev;
904 joydev->dev.release = joydev_free;
905 device_initialize(&joydev->dev);
906
907 error = input_register_handle(&joydev->handle);
908 if (error)
909 goto err_free_joydev;
910
911 cdev_init(&joydev->cdev, &joydev_fops);
912 joydev->cdev.kobj.parent = &joydev->dev.kobj;
913 error = cdev_add(&joydev->cdev, joydev->dev.devt, 1);
914 if (error)
915 goto err_unregister_handle;
916
917 error = device_add(&joydev->dev);
918 if (error)
919 goto err_cleanup_joydev;
920
921 return 0;
922
923 err_cleanup_joydev:
924 joydev_cleanup(joydev);
925 err_unregister_handle:
926 input_unregister_handle(&joydev->handle);
927 err_free_joydev:
928 put_device(&joydev->dev);
929 err_free_minor:
930 input_free_minor(minor);
931 return error;
932 }
933
joydev_disconnect(struct input_handle * handle)934 static void joydev_disconnect(struct input_handle *handle)
935 {
936 struct joydev *joydev = handle->private;
937
938 device_del(&joydev->dev);
939 joydev_cleanup(joydev);
940 input_free_minor(MINOR(joydev->dev.devt));
941 input_unregister_handle(handle);
942 put_device(&joydev->dev);
943 }
944
945 static const struct input_device_id joydev_ids[] = {
946 {
947 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
948 INPUT_DEVICE_ID_MATCH_ABSBIT,
949 .evbit = { BIT_MASK(EV_ABS) },
950 .absbit = { BIT_MASK(ABS_X) },
951 },
952 {
953 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
954 INPUT_DEVICE_ID_MATCH_ABSBIT,
955 .evbit = { BIT_MASK(EV_ABS) },
956 .absbit = { BIT_MASK(ABS_WHEEL) },
957 },
958 {
959 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
960 INPUT_DEVICE_ID_MATCH_ABSBIT,
961 .evbit = { BIT_MASK(EV_ABS) },
962 .absbit = { BIT_MASK(ABS_THROTTLE) },
963 },
964 {
965 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
966 INPUT_DEVICE_ID_MATCH_KEYBIT,
967 .evbit = { BIT_MASK(EV_KEY) },
968 .keybit = {[BIT_WORD(BTN_JOYSTICK)] = BIT_MASK(BTN_JOYSTICK) },
969 },
970 {
971 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
972 INPUT_DEVICE_ID_MATCH_KEYBIT,
973 .evbit = { BIT_MASK(EV_KEY) },
974 .keybit = { [BIT_WORD(BTN_GAMEPAD)] = BIT_MASK(BTN_GAMEPAD) },
975 },
976 {
977 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
978 INPUT_DEVICE_ID_MATCH_KEYBIT,
979 .evbit = { BIT_MASK(EV_KEY) },
980 .keybit = { [BIT_WORD(BTN_TRIGGER_HAPPY)] = BIT_MASK(BTN_TRIGGER_HAPPY) },
981 },
982 { } /* Terminating entry */
983 };
984
985 MODULE_DEVICE_TABLE(input, joydev_ids);
986
987 static struct input_handler joydev_handler = {
988 .event = joydev_event,
989 .match = joydev_match,
990 .connect = joydev_connect,
991 .disconnect = joydev_disconnect,
992 .legacy_minors = true,
993 .minor = JOYDEV_MINOR_BASE,
994 .name = "joydev",
995 .id_table = joydev_ids,
996 };
997
joydev_init(void)998 static int __init joydev_init(void)
999 {
1000 return input_register_handler(&joydev_handler);
1001 }
1002
joydev_exit(void)1003 static void __exit joydev_exit(void)
1004 {
1005 input_unregister_handler(&joydev_handler);
1006 }
1007
1008 module_init(joydev_init);
1009 module_exit(joydev_exit);
1010