Root/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#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
32MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
33MODULE_DESCRIPTION("Joystick device interfaces");
34MODULE_SUPPORTED_DEVICE("input/js");
35MODULE_LICENSE("GPL");
36
37#define JOYDEV_MINOR_BASE 0
38#define JOYDEV_MINORS 16
39#define JOYDEV_BUFFER_SIZE 64
40
41struct 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
63struct 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
74static 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
94static 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
118static 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
159static 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
166static 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
174static 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
182static 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
191static 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
211static 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 */
225static 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
237static 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
250static 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
280static 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
312static 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 */
333static 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
368static 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
376static 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 */
427static 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
437static 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 = kmalloc(len, GFP_KERNEL);
448    if (!abspam)
449        return -ENOMEM;
450
451    if (copy_from_user(abspam, argp, len)) {
452        retval = -EFAULT;
453        goto out;
454    }
455
456    for (i = 0; i < joydev->nabs; i++) {
457        if (abspam[i] > ABS_MAX) {
458            retval = -EINVAL;
459            goto out;
460        }
461    }
462
463    memcpy(joydev->abspam, abspam, len);
464
465    for (i = 0; i < joydev->nabs; i++)
466        joydev->absmap[joydev->abspam[i]] = i;
467
468 out:
469    kfree(abspam);
470    return retval;
471}
472
473static int joydev_handle_JSIOCSBTNMAP(struct joydev *joydev,
474                      void __user *argp, size_t len)
475{
476    __u16 *keypam;
477    int i;
478    int retval = 0;
479
480    len = min(len, sizeof(joydev->keypam));
481
482    /* Validate the map. */
483    keypam = kmalloc(len, GFP_KERNEL);
484    if (!keypam)
485        return -ENOMEM;
486
487    if (copy_from_user(keypam, argp, len)) {
488        retval = -EFAULT;
489        goto out;
490    }
491
492    for (i = 0; i < joydev->nkey; i++) {
493        if (keypam[i] > KEY_MAX || keypam[i] < BTN_MISC) {
494            retval = -EINVAL;
495            goto out;
496        }
497    }
498
499    memcpy(joydev->keypam, keypam, len);
500
501    for (i = 0; i < joydev->nkey; i++)
502        joydev->keymap[keypam[i] - BTN_MISC] = i;
503
504 out:
505    kfree(keypam);
506    return retval;
507}
508
509
510static int joydev_ioctl_common(struct joydev *joydev,
511                unsigned int cmd, void __user *argp)
512{
513    struct input_dev *dev = joydev->handle.dev;
514    size_t len;
515    int i;
516    const char *name;
517
518    /* Process fixed-sized commands. */
519    switch (cmd) {
520
521    case JS_SET_CAL:
522        return copy_from_user(&joydev->glue.JS_CORR, argp,
523                sizeof(joydev->glue.JS_CORR)) ? -EFAULT : 0;
524
525    case JS_GET_CAL:
526        return copy_to_user(argp, &joydev->glue.JS_CORR,
527                sizeof(joydev->glue.JS_CORR)) ? -EFAULT : 0;
528
529    case JS_SET_TIMEOUT:
530        return get_user(joydev->glue.JS_TIMEOUT, (s32 __user *) argp);
531
532    case JS_GET_TIMEOUT:
533        return put_user(joydev->glue.JS_TIMEOUT, (s32 __user *) argp);
534
535    case JSIOCGVERSION:
536        return put_user(JS_VERSION, (__u32 __user *) argp);
537
538    case JSIOCGAXES:
539        return put_user(joydev->nabs, (__u8 __user *) argp);
540
541    case JSIOCGBUTTONS:
542        return put_user(joydev->nkey, (__u8 __user *) argp);
543
544    case JSIOCSCORR:
545        if (copy_from_user(joydev->corr, argp,
546                  sizeof(joydev->corr[0]) * joydev->nabs))
547            return -EFAULT;
548
549        for (i = 0; i < joydev->nabs; i++) {
550            int val = input_abs_get_val(dev, joydev->abspam[i]);
551            joydev->abs[i] = joydev_correct(val, &joydev->corr[i]);
552        }
553        return 0;
554
555    case JSIOCGCORR:
556        return copy_to_user(argp, joydev->corr,
557            sizeof(joydev->corr[0]) * joydev->nabs) ? -EFAULT : 0;
558
559    }
560
561    /*
562     * Process variable-sized commands (the axis and button map commands
563     * are considered variable-sized to decouple them from the values of
564     * ABS_MAX and KEY_MAX).
565     */
566    switch (cmd & ~IOCSIZE_MASK) {
567
568    case (JSIOCSAXMAP & ~IOCSIZE_MASK):
569        return joydev_handle_JSIOCSAXMAP(joydev, argp, _IOC_SIZE(cmd));
570
571    case (JSIOCGAXMAP & ~IOCSIZE_MASK):
572        len = min_t(size_t, _IOC_SIZE(cmd), sizeof(joydev->abspam));
573        return copy_to_user(argp, joydev->abspam, len) ? -EFAULT : len;
574
575    case (JSIOCSBTNMAP & ~IOCSIZE_MASK):
576        return joydev_handle_JSIOCSBTNMAP(joydev, argp, _IOC_SIZE(cmd));
577
578    case (JSIOCGBTNMAP & ~IOCSIZE_MASK):
579        len = min_t(size_t, _IOC_SIZE(cmd), sizeof(joydev->keypam));
580        return copy_to_user(argp, joydev->keypam, len) ? -EFAULT : len;
581
582    case JSIOCGNAME(0):
583        name = dev->name;
584        if (!name)
585            return 0;
586
587        len = min_t(size_t, _IOC_SIZE(cmd), strlen(name) + 1);
588        return copy_to_user(argp, name, len) ? -EFAULT : len;
589    }
590
591    return -EINVAL;
592}
593
594#ifdef CONFIG_COMPAT
595static long joydev_compat_ioctl(struct file *file,
596                unsigned int cmd, unsigned long arg)
597{
598    struct joydev_client *client = file->private_data;
599    struct joydev *joydev = client->joydev;
600    void __user *argp = (void __user *)arg;
601    s32 tmp32;
602    struct JS_DATA_SAVE_TYPE_32 ds32;
603    int retval;
604
605    retval = mutex_lock_interruptible(&joydev->mutex);
606    if (retval)
607        return retval;
608
609    if (!joydev->exist) {
610        retval = -ENODEV;
611        goto out;
612    }
613
614    switch (cmd) {
615
616    case JS_SET_TIMELIMIT:
617        retval = get_user(tmp32, (s32 __user *) arg);
618        if (retval == 0)
619            joydev->glue.JS_TIMELIMIT = tmp32;
620        break;
621
622    case JS_GET_TIMELIMIT:
623        tmp32 = joydev->glue.JS_TIMELIMIT;
624        retval = put_user(tmp32, (s32 __user *) arg);
625        break;
626
627    case JS_SET_ALL:
628        retval = copy_from_user(&ds32, argp,
629                    sizeof(ds32)) ? -EFAULT : 0;
630        if (retval == 0) {
631            joydev->glue.JS_TIMEOUT = ds32.JS_TIMEOUT;
632            joydev->glue.BUSY = ds32.BUSY;
633            joydev->glue.JS_EXPIRETIME = ds32.JS_EXPIRETIME;
634            joydev->glue.JS_TIMELIMIT = ds32.JS_TIMELIMIT;
635            joydev->glue.JS_SAVE = ds32.JS_SAVE;
636            joydev->glue.JS_CORR = ds32.JS_CORR;
637        }
638        break;
639
640    case JS_GET_ALL:
641        ds32.JS_TIMEOUT = joydev->glue.JS_TIMEOUT;
642        ds32.BUSY = joydev->glue.BUSY;
643        ds32.JS_EXPIRETIME = joydev->glue.JS_EXPIRETIME;
644        ds32.JS_TIMELIMIT = joydev->glue.JS_TIMELIMIT;
645        ds32.JS_SAVE = joydev->glue.JS_SAVE;
646        ds32.JS_CORR = joydev->glue.JS_CORR;
647
648        retval = copy_to_user(argp, &ds32, sizeof(ds32)) ? -EFAULT : 0;
649        break;
650
651    default:
652        retval = joydev_ioctl_common(joydev, cmd, argp);
653        break;
654    }
655
656 out:
657    mutex_unlock(&joydev->mutex);
658    return retval;
659}
660#endif /* CONFIG_COMPAT */
661
662static long joydev_ioctl(struct file *file,
663             unsigned int cmd, unsigned long arg)
664{
665    struct joydev_client *client = file->private_data;
666    struct joydev *joydev = client->joydev;
667    void __user *argp = (void __user *)arg;
668    int retval;
669
670    retval = mutex_lock_interruptible(&joydev->mutex);
671    if (retval)
672        return retval;
673
674    if (!joydev->exist) {
675        retval = -ENODEV;
676        goto out;
677    }
678
679    switch (cmd) {
680
681    case JS_SET_TIMELIMIT:
682        retval = get_user(joydev->glue.JS_TIMELIMIT,
683                  (long __user *) arg);
684        break;
685
686    case JS_GET_TIMELIMIT:
687        retval = put_user(joydev->glue.JS_TIMELIMIT,
688                  (long __user *) arg);
689        break;
690
691    case JS_SET_ALL:
692        retval = copy_from_user(&joydev->glue, argp,
693                    sizeof(joydev->glue)) ? -EFAULT : 0;
694        break;
695
696    case JS_GET_ALL:
697        retval = copy_to_user(argp, &joydev->glue,
698                      sizeof(joydev->glue)) ? -EFAULT : 0;
699        break;
700
701    default:
702        retval = joydev_ioctl_common(joydev, cmd, argp);
703        break;
704    }
705 out:
706    mutex_unlock(&joydev->mutex);
707    return retval;
708}
709
710static const struct file_operations joydev_fops = {
711    .owner = THIS_MODULE,
712    .read = joydev_read,
713    .poll = joydev_poll,
714    .open = joydev_open,
715    .release = joydev_release,
716    .unlocked_ioctl = joydev_ioctl,
717#ifdef CONFIG_COMPAT
718    .compat_ioctl = joydev_compat_ioctl,
719#endif
720    .fasync = joydev_fasync,
721    .llseek = no_llseek,
722};
723
724/*
725 * Mark device non-existent. This disables writes, ioctls and
726 * prevents new users from opening the device. Already posted
727 * blocking reads will stay, however new ones will fail.
728 */
729static void joydev_mark_dead(struct joydev *joydev)
730{
731    mutex_lock(&joydev->mutex);
732    joydev->exist = false;
733    mutex_unlock(&joydev->mutex);
734}
735
736static void joydev_cleanup(struct joydev *joydev)
737{
738    struct input_handle *handle = &joydev->handle;
739
740    joydev_mark_dead(joydev);
741    joydev_hangup(joydev);
742
743    cdev_del(&joydev->cdev);
744
745    /* joydev is marked dead so no one else accesses joydev->open */
746    if (joydev->open)
747        input_close_device(handle);
748}
749
750
751static bool joydev_match(struct input_handler *handler, struct input_dev *dev)
752{
753    /* Avoid touchpads and touchscreens */
754    if (test_bit(EV_KEY, dev->evbit) && test_bit(BTN_TOUCH, dev->keybit))
755        return false;
756
757    /* Avoid tablets, digitisers and similar devices */
758    if (test_bit(EV_KEY, dev->evbit) && test_bit(BTN_DIGI, dev->keybit))
759        return false;
760
761    return true;
762}
763
764static int joydev_connect(struct input_handler *handler, struct input_dev *dev,
765              const struct input_device_id *id)
766{
767    struct joydev *joydev;
768    int i, j, t, minor, dev_no;
769    int error;
770
771    minor = input_get_new_minor(JOYDEV_MINOR_BASE, JOYDEV_MINORS, true);
772    if (minor < 0) {
773        error = minor;
774        pr_err("failed to reserve new minor: %d\n", error);
775        return error;
776    }
777
778    joydev = kzalloc(sizeof(struct joydev), GFP_KERNEL);
779    if (!joydev) {
780        error = -ENOMEM;
781        goto err_free_minor;
782    }
783
784    INIT_LIST_HEAD(&joydev->client_list);
785    spin_lock_init(&joydev->client_lock);
786    mutex_init(&joydev->mutex);
787    init_waitqueue_head(&joydev->wait);
788    joydev->exist = true;
789
790    dev_no = minor;
791    /* Normalize device number if it falls into legacy range */
792    if (dev_no < JOYDEV_MINOR_BASE + JOYDEV_MINORS)
793        dev_no -= JOYDEV_MINOR_BASE;
794    dev_set_name(&joydev->dev, "js%d", dev_no);
795
796    joydev->handle.dev = input_get_device(dev);
797    joydev->handle.name = dev_name(&joydev->dev);
798    joydev->handle.handler = handler;
799    joydev->handle.private = joydev;
800
801    for (i = 0; i < ABS_CNT; i++)
802        if (test_bit(i, dev->absbit)) {
803            joydev->absmap[i] = joydev->nabs;
804            joydev->abspam[joydev->nabs] = i;
805            joydev->nabs++;
806        }
807
808    for (i = BTN_JOYSTICK - BTN_MISC; i < KEY_MAX - BTN_MISC + 1; i++)
809        if (test_bit(i + BTN_MISC, dev->keybit)) {
810            joydev->keymap[i] = joydev->nkey;
811            joydev->keypam[joydev->nkey] = i + BTN_MISC;
812            joydev->nkey++;
813        }
814
815    for (i = 0; i < BTN_JOYSTICK - BTN_MISC; i++)
816        if (test_bit(i + BTN_MISC, dev->keybit)) {
817            joydev->keymap[i] = joydev->nkey;
818            joydev->keypam[joydev->nkey] = i + BTN_MISC;
819            joydev->nkey++;
820        }
821
822    for (i = 0; i < joydev->nabs; i++) {
823        j = joydev->abspam[i];
824        if (input_abs_get_max(dev, j) == input_abs_get_min(dev, j)) {
825            joydev->corr[i].type = JS_CORR_NONE;
826            joydev->abs[i] = input_abs_get_val(dev, j);
827            continue;
828        }
829        joydev->corr[i].type = JS_CORR_BROKEN;
830        joydev->corr[i].prec = input_abs_get_fuzz(dev, j);
831
832        t = (input_abs_get_max(dev, j) + input_abs_get_min(dev, j)) / 2;
833        joydev->corr[i].coef[0] = t - input_abs_get_flat(dev, j);
834        joydev->corr[i].coef[1] = t + input_abs_get_flat(dev, j);
835
836        t = (input_abs_get_max(dev, j) - input_abs_get_min(dev, j)) / 2
837            - 2 * input_abs_get_flat(dev, j);
838        if (t) {
839            joydev->corr[i].coef[2] = (1 << 29) / t;
840            joydev->corr[i].coef[3] = (1 << 29) / t;
841
842            joydev->abs[i] =
843                joydev_correct(input_abs_get_val(dev, j),
844                           joydev->corr + i);
845        }
846    }
847
848    joydev->dev.devt = MKDEV(INPUT_MAJOR, minor);
849    joydev->dev.class = &input_class;
850    joydev->dev.parent = &dev->dev;
851    joydev->dev.release = joydev_free;
852    device_initialize(&joydev->dev);
853
854    error = input_register_handle(&joydev->handle);
855    if (error)
856        goto err_free_joydev;
857
858    cdev_init(&joydev->cdev, &joydev_fops);
859    joydev->cdev.kobj.parent = &joydev->dev.kobj;
860    error = cdev_add(&joydev->cdev, joydev->dev.devt, 1);
861    if (error)
862        goto err_unregister_handle;
863
864    error = device_add(&joydev->dev);
865    if (error)
866        goto err_cleanup_joydev;
867
868    return 0;
869
870 err_cleanup_joydev:
871    joydev_cleanup(joydev);
872 err_unregister_handle:
873    input_unregister_handle(&joydev->handle);
874 err_free_joydev:
875    put_device(&joydev->dev);
876 err_free_minor:
877    input_free_minor(minor);
878    return error;
879}
880
881static void joydev_disconnect(struct input_handle *handle)
882{
883    struct joydev *joydev = handle->private;
884
885    device_del(&joydev->dev);
886    joydev_cleanup(joydev);
887    input_free_minor(MINOR(joydev->dev.devt));
888    input_unregister_handle(handle);
889    put_device(&joydev->dev);
890}
891
892static const struct input_device_id joydev_ids[] = {
893    {
894        .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
895                INPUT_DEVICE_ID_MATCH_ABSBIT,
896        .evbit = { BIT_MASK(EV_ABS) },
897        .absbit = { BIT_MASK(ABS_X) },
898    },
899    {
900        .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
901                INPUT_DEVICE_ID_MATCH_ABSBIT,
902        .evbit = { BIT_MASK(EV_ABS) },
903        .absbit = { BIT_MASK(ABS_WHEEL) },
904    },
905    {
906        .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
907                INPUT_DEVICE_ID_MATCH_ABSBIT,
908        .evbit = { BIT_MASK(EV_ABS) },
909        .absbit = { BIT_MASK(ABS_THROTTLE) },
910    },
911    {
912        .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
913                INPUT_DEVICE_ID_MATCH_KEYBIT,
914        .evbit = { BIT_MASK(EV_KEY) },
915        .keybit = {[BIT_WORD(BTN_JOYSTICK)] = BIT_MASK(BTN_JOYSTICK) },
916    },
917    {
918        .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
919                INPUT_DEVICE_ID_MATCH_KEYBIT,
920        .evbit = { BIT_MASK(EV_KEY) },
921        .keybit = { [BIT_WORD(BTN_GAMEPAD)] = BIT_MASK(BTN_GAMEPAD) },
922    },
923    {
924        .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
925                INPUT_DEVICE_ID_MATCH_KEYBIT,
926        .evbit = { BIT_MASK(EV_KEY) },
927        .keybit = { [BIT_WORD(BTN_TRIGGER_HAPPY)] = BIT_MASK(BTN_TRIGGER_HAPPY) },
928    },
929    { } /* Terminating entry */
930};
931
932MODULE_DEVICE_TABLE(input, joydev_ids);
933
934static struct input_handler joydev_handler = {
935    .event = joydev_event,
936    .match = joydev_match,
937    .connect = joydev_connect,
938    .disconnect = joydev_disconnect,
939    .legacy_minors = true,
940    .minor = JOYDEV_MINOR_BASE,
941    .name = "joydev",
942    .id_table = joydev_ids,
943};
944
945static int __init joydev_init(void)
946{
947    return input_register_handler(&joydev_handler);
948}
949
950static void __exit joydev_exit(void)
951{
952    input_unregister_handler(&joydev_handler);
953}
954
955module_init(joydev_init);
956module_exit(joydev_exit);
957

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