xref: /linux/drivers/input/joydev.c (revision f3d9478b2ce468c3115b02ecae7e975990697f15)
1 /*
2  * Joystick device driver for the input driver suite.
3  *
4  * Copyright (c) 1999-2002 Vojtech Pavlik
5  * Copyright (c) 1999 Colin Van Dyke
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11  */
12 
13 #include <asm/io.h>
14 #include <asm/system.h>
15 #include <linux/delay.h>
16 #include <linux/errno.h>
17 #include <linux/joystick.h>
18 #include <linux/input.h>
19 #include <linux/kernel.h>
20 #include <linux/major.h>
21 #include <linux/slab.h>
22 #include <linux/mm.h>
23 #include <linux/miscdevice.h>
24 #include <linux/module.h>
25 #include <linux/poll.h>
26 #include <linux/init.h>
27 #include <linux/smp_lock.h>
28 #include <linux/device.h>
29 
30 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
31 MODULE_DESCRIPTION("Joystick device interfaces");
32 MODULE_SUPPORTED_DEVICE("input/js");
33 MODULE_LICENSE("GPL");
34 
35 #define JOYDEV_MINOR_BASE	0
36 #define JOYDEV_MINORS		16
37 #define JOYDEV_BUFFER_SIZE	64
38 
39 struct joydev {
40 	int exist;
41 	int open;
42 	int minor;
43 	char name[16];
44 	struct input_handle handle;
45 	wait_queue_head_t wait;
46 	struct list_head list;
47 	struct js_corr corr[ABS_MAX + 1];
48 	struct JS_DATA_SAVE_TYPE glue;
49 	int nabs;
50 	int nkey;
51 	__u16 keymap[KEY_MAX - BTN_MISC + 1];
52 	__u16 keypam[KEY_MAX - BTN_MISC + 1];
53 	__u8 absmap[ABS_MAX + 1];
54 	__u8 abspam[ABS_MAX + 1];
55 	__s16 abs[ABS_MAX + 1];
56 };
57 
58 struct joydev_list {
59 	struct js_event buffer[JOYDEV_BUFFER_SIZE];
60 	int head;
61 	int tail;
62 	int startup;
63 	struct fasync_struct *fasync;
64 	struct joydev *joydev;
65 	struct list_head node;
66 };
67 
68 static struct joydev *joydev_table[JOYDEV_MINORS];
69 
70 static int joydev_correct(int value, struct js_corr *corr)
71 {
72 	switch (corr->type) {
73 		case JS_CORR_NONE:
74 			break;
75 		case JS_CORR_BROKEN:
76 			value = value > corr->coef[0] ? (value < corr->coef[1] ? 0 :
77 				((corr->coef[3] * (value - corr->coef[1])) >> 14)) :
78 				((corr->coef[2] * (value - corr->coef[0])) >> 14);
79 			break;
80 		default:
81 			return 0;
82 	}
83 
84 	if (value < -32767) return -32767;
85 	if (value >  32767) return  32767;
86 
87 	return value;
88 }
89 
90 static void joydev_event(struct input_handle *handle, unsigned int type, unsigned int code, int value)
91 {
92 	struct joydev *joydev = handle->private;
93 	struct joydev_list *list;
94 	struct js_event event;
95 
96 	switch (type) {
97 
98 		case EV_KEY:
99 			if (code < BTN_MISC || value == 2) return;
100 			event.type = JS_EVENT_BUTTON;
101 			event.number = joydev->keymap[code - BTN_MISC];
102 			event.value = value;
103 			break;
104 
105 		case EV_ABS:
106 			event.type = JS_EVENT_AXIS;
107 			event.number = joydev->absmap[code];
108 			event.value = joydev_correct(value, joydev->corr + event.number);
109 			if (event.value == joydev->abs[event.number]) return;
110 			joydev->abs[event.number] = event.value;
111 			break;
112 
113 		default:
114 			return;
115 	}
116 
117 	event.time = jiffies_to_msecs(jiffies);
118 
119 	list_for_each_entry(list, &joydev->list, node) {
120 
121 		memcpy(list->buffer + list->head, &event, sizeof(struct js_event));
122 
123 		if (list->startup == joydev->nabs + joydev->nkey)
124 			if (list->tail == (list->head = (list->head + 1) & (JOYDEV_BUFFER_SIZE - 1)))
125 				list->startup = 0;
126 
127 		kill_fasync(&list->fasync, SIGIO, POLL_IN);
128 	}
129 
130 	wake_up_interruptible(&joydev->wait);
131 }
132 
133 static int joydev_fasync(int fd, struct file *file, int on)
134 {
135 	int retval;
136 	struct joydev_list *list = file->private_data;
137 	retval = fasync_helper(fd, file, on, &list->fasync);
138 	return retval < 0 ? retval : 0;
139 }
140 
141 static void joydev_free(struct joydev *joydev)
142 {
143 	joydev_table[joydev->minor] = NULL;
144 	kfree(joydev);
145 }
146 
147 static int joydev_release(struct inode * inode, struct file * file)
148 {
149 	struct joydev_list *list = file->private_data;
150 
151 	joydev_fasync(-1, file, 0);
152 
153 	list_del(&list->node);
154 
155 	if (!--list->joydev->open) {
156 		if (list->joydev->exist)
157 			input_close_device(&list->joydev->handle);
158 		else
159 			joydev_free(list->joydev);
160 	}
161 
162 	kfree(list);
163 	return 0;
164 }
165 
166 static int joydev_open(struct inode *inode, struct file *file)
167 {
168 	struct joydev_list *list;
169 	int i = iminor(inode) - JOYDEV_MINOR_BASE;
170 
171 	if (i >= JOYDEV_MINORS || !joydev_table[i])
172 		return -ENODEV;
173 
174 	if (!(list = kzalloc(sizeof(struct joydev_list), GFP_KERNEL)))
175 		return -ENOMEM;
176 
177 	list->joydev = joydev_table[i];
178 	list_add_tail(&list->node, &joydev_table[i]->list);
179 	file->private_data = list;
180 
181 	if (!list->joydev->open++)
182 		if (list->joydev->exist)
183 			input_open_device(&list->joydev->handle);
184 
185 	return 0;
186 }
187 
188 static ssize_t joydev_write(struct file * file, const char __user * buffer, size_t count, loff_t *ppos)
189 {
190 	return -EINVAL;
191 }
192 
193 static ssize_t joydev_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
194 {
195 	struct joydev_list *list = file->private_data;
196 	struct joydev *joydev = list->joydev;
197 	struct input_dev *input = joydev->handle.dev;
198 	int retval = 0;
199 
200 	if (!list->joydev->exist)
201 		return -ENODEV;
202 
203 	if (count < sizeof(struct js_event))
204 		return -EINVAL;
205 
206 	if (count == sizeof(struct JS_DATA_TYPE)) {
207 
208 		struct JS_DATA_TYPE data;
209 		int i;
210 
211 		for (data.buttons = i = 0; i < 32 && i < joydev->nkey; i++)
212 			data.buttons |= test_bit(joydev->keypam[i], input->key) ? (1 << i) : 0;
213 		data.x = (joydev->abs[0] / 256 + 128) >> joydev->glue.JS_CORR.x;
214 		data.y = (joydev->abs[1] / 256 + 128) >> joydev->glue.JS_CORR.y;
215 
216 		if (copy_to_user(buf, &data, sizeof(struct JS_DATA_TYPE)))
217 			return -EFAULT;
218 
219 		list->startup = 0;
220 		list->tail = list->head;
221 
222 		return sizeof(struct JS_DATA_TYPE);
223 	}
224 
225 	if (list->startup == joydev->nabs + joydev->nkey
226 		&& list->head == list->tail && (file->f_flags & O_NONBLOCK))
227 			return -EAGAIN;
228 
229 	retval = wait_event_interruptible(list->joydev->wait,
230 		 			  !list->joydev->exist ||
231 					  list->startup < joydev->nabs + joydev->nkey ||
232 					  list->head != list->tail);
233 
234 	if (retval)
235 		return retval;
236 
237 	if (!list->joydev->exist)
238 		return -ENODEV;
239 
240 	while (list->startup < joydev->nabs + joydev->nkey && retval + sizeof(struct js_event) <= count) {
241 
242 		struct js_event event;
243 
244 		event.time = jiffies_to_msecs(jiffies);
245 
246 		if (list->startup < joydev->nkey) {
247 			event.type = JS_EVENT_BUTTON | JS_EVENT_INIT;
248 			event.number = list->startup;
249 			event.value = !!test_bit(joydev->keypam[event.number], input->key);
250 		} else {
251 			event.type = JS_EVENT_AXIS | JS_EVENT_INIT;
252 			event.number = list->startup - joydev->nkey;
253 			event.value = joydev->abs[event.number];
254 		}
255 
256 		if (copy_to_user(buf + retval, &event, sizeof(struct js_event)))
257 			return -EFAULT;
258 
259 		list->startup++;
260 		retval += sizeof(struct js_event);
261 	}
262 
263 	while (list->head != list->tail && retval + sizeof(struct js_event) <= count) {
264 
265 		if (copy_to_user(buf + retval, list->buffer + list->tail, sizeof(struct js_event)))
266 			return -EFAULT;
267 
268 		list->tail = (list->tail + 1) & (JOYDEV_BUFFER_SIZE - 1);
269 		retval += sizeof(struct js_event);
270 	}
271 
272 	return retval;
273 }
274 
275 /* No kernel lock - fine */
276 static unsigned int joydev_poll(struct file *file, poll_table *wait)
277 {
278 	struct joydev_list *list = file->private_data;
279 	poll_wait(file, &list->joydev->wait, wait);
280 	return ((list->head != list->tail || list->startup < list->joydev->nabs + list->joydev->nkey) ?
281 		(POLLIN | POLLRDNORM) : 0) | (list->joydev->exist ? 0 : (POLLHUP | POLLERR));
282 }
283 
284 static int joydev_ioctl_common(struct joydev *joydev, unsigned int cmd, void __user *argp)
285 {
286 	struct input_dev *dev = joydev->handle.dev;
287 	int i, j;
288 
289 	switch (cmd) {
290 
291 		case JS_SET_CAL:
292 			return copy_from_user(&joydev->glue.JS_CORR, argp,
293 				sizeof(joydev->glue.JS_CORR)) ? -EFAULT : 0;
294 		case JS_GET_CAL:
295 			return copy_to_user(argp, &joydev->glue.JS_CORR,
296 				sizeof(joydev->glue.JS_CORR)) ? -EFAULT : 0;
297 		case JS_SET_TIMEOUT:
298 			return get_user(joydev->glue.JS_TIMEOUT, (s32 __user *) argp);
299 		case JS_GET_TIMEOUT:
300 			return put_user(joydev->glue.JS_TIMEOUT, (s32 __user *) argp);
301 
302 		case JSIOCGVERSION:
303 			return put_user(JS_VERSION, (__u32 __user *) argp);
304 		case JSIOCGAXES:
305 			return put_user(joydev->nabs, (__u8 __user *) argp);
306 		case JSIOCGBUTTONS:
307 			return put_user(joydev->nkey, (__u8 __user *) argp);
308 		case JSIOCSCORR:
309 			if (copy_from_user(joydev->corr, argp,
310 				      sizeof(joydev->corr[0]) * joydev->nabs))
311 			    return -EFAULT;
312 			for (i = 0; i < joydev->nabs; i++) {
313 				j = joydev->abspam[i];
314 			        joydev->abs[i] = joydev_correct(dev->abs[j], joydev->corr + i);
315 			}
316 			return 0;
317 		case JSIOCGCORR:
318 			return copy_to_user(argp, joydev->corr,
319 						sizeof(joydev->corr[0]) * joydev->nabs) ? -EFAULT : 0;
320 		case JSIOCSAXMAP:
321 			if (copy_from_user(joydev->abspam, argp, sizeof(__u8) * (ABS_MAX + 1)))
322 				return -EFAULT;
323 			for (i = 0; i < joydev->nabs; i++) {
324 				if (joydev->abspam[i] > ABS_MAX) return -EINVAL;
325 				joydev->absmap[joydev->abspam[i]] = i;
326 			}
327 			return 0;
328 		case JSIOCGAXMAP:
329 			return copy_to_user(argp, joydev->abspam,
330 						sizeof(__u8) * (ABS_MAX + 1)) ? -EFAULT : 0;
331 		case JSIOCSBTNMAP:
332 			if (copy_from_user(joydev->keypam, argp, sizeof(__u16) * (KEY_MAX - BTN_MISC + 1)))
333 				return -EFAULT;
334 			for (i = 0; i < joydev->nkey; i++) {
335 				if (joydev->keypam[i] > KEY_MAX || joydev->keypam[i] < BTN_MISC) return -EINVAL;
336 				joydev->keymap[joydev->keypam[i] - BTN_MISC] = i;
337 			}
338 			return 0;
339 		case JSIOCGBTNMAP:
340 			return copy_to_user(argp, joydev->keypam,
341 						sizeof(__u16) * (KEY_MAX - BTN_MISC + 1)) ? -EFAULT : 0;
342 		default:
343 			if ((cmd & ~(_IOC_SIZEMASK << _IOC_SIZESHIFT)) == JSIOCGNAME(0)) {
344 				int len;
345 				if (!dev->name) return 0;
346 				len = strlen(dev->name) + 1;
347 				if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd);
348 				if (copy_to_user(argp, dev->name, len)) return -EFAULT;
349 				return len;
350 			}
351 	}
352 	return -EINVAL;
353 }
354 
355 #ifdef CONFIG_COMPAT
356 static long joydev_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
357 {
358 	struct joydev_list *list = file->private_data;
359 	struct joydev *joydev = list->joydev;
360 	void __user *argp = (void __user *)arg;
361 	s32 tmp32;
362 	struct JS_DATA_SAVE_TYPE_32 ds32;
363 	int err;
364 
365 	if (!joydev->exist) return -ENODEV;
366 	switch(cmd) {
367 	case JS_SET_TIMELIMIT:
368 		err = get_user(tmp32, (s32 __user *) arg);
369 		if (err == 0)
370 			joydev->glue.JS_TIMELIMIT = tmp32;
371 		break;
372 	case JS_GET_TIMELIMIT:
373 		tmp32 = joydev->glue.JS_TIMELIMIT;
374 		err = put_user(tmp32, (s32 __user *) arg);
375 		break;
376 
377 	case JS_SET_ALL:
378 		err = copy_from_user(&ds32, argp,
379 				     sizeof(ds32)) ? -EFAULT : 0;
380 		if (err == 0) {
381 			joydev->glue.JS_TIMEOUT    = ds32.JS_TIMEOUT;
382 			joydev->glue.BUSY          = ds32.BUSY;
383 			joydev->glue.JS_EXPIRETIME = ds32.JS_EXPIRETIME;
384 			joydev->glue.JS_TIMELIMIT  = ds32.JS_TIMELIMIT;
385 			joydev->glue.JS_SAVE       = ds32.JS_SAVE;
386 			joydev->glue.JS_CORR       = ds32.JS_CORR;
387 		}
388 		break;
389 
390 	case JS_GET_ALL:
391 		ds32.JS_TIMEOUT    = joydev->glue.JS_TIMEOUT;
392 		ds32.BUSY          = joydev->glue.BUSY;
393 		ds32.JS_EXPIRETIME = joydev->glue.JS_EXPIRETIME;
394 		ds32.JS_TIMELIMIT  = joydev->glue.JS_TIMELIMIT;
395 		ds32.JS_SAVE       = joydev->glue.JS_SAVE;
396 		ds32.JS_CORR       = joydev->glue.JS_CORR;
397 
398 		err = copy_to_user(argp, &ds32,
399 					  sizeof(ds32)) ? -EFAULT : 0;
400 		break;
401 
402 	default:
403 		err = joydev_ioctl_common(joydev, cmd, argp);
404 	}
405 	return err;
406 }
407 #endif /* CONFIG_COMPAT */
408 
409 static int joydev_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
410 {
411 	struct joydev_list *list = file->private_data;
412 	struct joydev *joydev = list->joydev;
413 	void __user *argp = (void __user *)arg;
414 
415 	if (!joydev->exist) return -ENODEV;
416 
417 	switch(cmd) {
418 		case JS_SET_TIMELIMIT:
419 			return get_user(joydev->glue.JS_TIMELIMIT, (long __user *) arg);
420 		case JS_GET_TIMELIMIT:
421 			return put_user(joydev->glue.JS_TIMELIMIT, (long __user *) arg);
422 		case JS_SET_ALL:
423 			return copy_from_user(&joydev->glue, argp,
424 						sizeof(joydev->glue)) ? -EFAULT : 0;
425 		case JS_GET_ALL:
426 			return copy_to_user(argp, &joydev->glue,
427 						sizeof(joydev->glue)) ? -EFAULT : 0;
428 		default:
429 			return joydev_ioctl_common(joydev, cmd, argp);
430 	}
431 }
432 
433 static struct file_operations joydev_fops = {
434 	.owner =	THIS_MODULE,
435 	.read =		joydev_read,
436 	.write =	joydev_write,
437 	.poll =		joydev_poll,
438 	.open =		joydev_open,
439 	.release =	joydev_release,
440 	.ioctl =	joydev_ioctl,
441 #ifdef CONFIG_COMPAT
442 	.compat_ioctl =	joydev_compat_ioctl,
443 #endif
444 	.fasync =	joydev_fasync,
445 };
446 
447 static struct input_handle *joydev_connect(struct input_handler *handler, struct input_dev *dev, struct input_device_id *id)
448 {
449 	struct joydev *joydev;
450 	struct class_device *cdev;
451 	int i, j, t, minor;
452 
453 	for (minor = 0; minor < JOYDEV_MINORS && joydev_table[minor]; minor++);
454 	if (minor == JOYDEV_MINORS) {
455 		printk(KERN_ERR "joydev: no more free joydev devices\n");
456 		return NULL;
457 	}
458 
459 	if (!(joydev = kzalloc(sizeof(struct joydev), GFP_KERNEL)))
460 		return NULL;
461 
462 	INIT_LIST_HEAD(&joydev->list);
463 	init_waitqueue_head(&joydev->wait);
464 
465 	joydev->minor = minor;
466 	joydev->exist = 1;
467 	joydev->handle.dev = dev;
468 	joydev->handle.name = joydev->name;
469 	joydev->handle.handler = handler;
470 	joydev->handle.private = joydev;
471 	sprintf(joydev->name, "js%d", minor);
472 
473 	for (i = 0; i < ABS_MAX + 1; i++)
474 		if (test_bit(i, dev->absbit)) {
475 			joydev->absmap[i] = joydev->nabs;
476 			joydev->abspam[joydev->nabs] = i;
477 			joydev->nabs++;
478 		}
479 
480 	for (i = BTN_JOYSTICK - BTN_MISC; i < KEY_MAX - BTN_MISC + 1; i++)
481 		if (test_bit(i + BTN_MISC, dev->keybit)) {
482 			joydev->keymap[i] = joydev->nkey;
483 			joydev->keypam[joydev->nkey] = i + BTN_MISC;
484 			joydev->nkey++;
485 		}
486 
487 	for (i = 0; i < BTN_JOYSTICK - BTN_MISC; i++)
488 		if (test_bit(i + BTN_MISC, dev->keybit)) {
489 			joydev->keymap[i] = joydev->nkey;
490 			joydev->keypam[joydev->nkey] = i + BTN_MISC;
491 			joydev->nkey++;
492 		}
493 
494 	for (i = 0; i < joydev->nabs; i++) {
495 		j = joydev->abspam[i];
496 		if (dev->absmax[j] == dev->absmin[j]) {
497 			joydev->corr[i].type = JS_CORR_NONE;
498 			joydev->abs[i] = dev->abs[j];
499 			continue;
500 		}
501 		joydev->corr[i].type = JS_CORR_BROKEN;
502 		joydev->corr[i].prec = dev->absfuzz[j];
503 		joydev->corr[i].coef[0] = (dev->absmax[j] + dev->absmin[j]) / 2 - dev->absflat[j];
504 		joydev->corr[i].coef[1] = (dev->absmax[j] + dev->absmin[j]) / 2 + dev->absflat[j];
505 		if (!(t = ((dev->absmax[j] - dev->absmin[j]) / 2 - 2 * dev->absflat[j])))
506 			continue;
507 		joydev->corr[i].coef[2] = (1 << 29) / t;
508 		joydev->corr[i].coef[3] = (1 << 29) / t;
509 
510 		joydev->abs[i] = joydev_correct(dev->abs[j], joydev->corr + i);
511 	}
512 
513 	joydev_table[minor] = joydev;
514 
515 	cdev = class_device_create(&input_class, &dev->cdev,
516 			MKDEV(INPUT_MAJOR, JOYDEV_MINOR_BASE + minor),
517 			dev->cdev.dev, joydev->name);
518 
519 	/* temporary symlink to keep userspace happy */
520 	sysfs_create_link(&input_class.subsys.kset.kobj, &cdev->kobj,
521 			  joydev->name);
522 
523 	return &joydev->handle;
524 }
525 
526 static void joydev_disconnect(struct input_handle *handle)
527 {
528 	struct joydev *joydev = handle->private;
529 	struct joydev_list *list;
530 
531 	sysfs_remove_link(&input_class.subsys.kset.kobj, joydev->name);
532 	class_device_destroy(&input_class, MKDEV(INPUT_MAJOR, JOYDEV_MINOR_BASE + joydev->minor));
533 	joydev->exist = 0;
534 
535 	if (joydev->open) {
536 		input_close_device(handle);
537 		wake_up_interruptible(&joydev->wait);
538 		list_for_each_entry(list, &joydev->list, node)
539 			kill_fasync(&list->fasync, SIGIO, POLL_HUP);
540 	} else
541 		joydev_free(joydev);
542 }
543 
544 static struct input_device_id joydev_blacklist[] = {
545 	{
546 		.flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_KEYBIT,
547 		.evbit = { BIT(EV_KEY) },
548 		.keybit = { [LONG(BTN_TOUCH)] = BIT(BTN_TOUCH) },
549 	}, 	/* Avoid itouchpads, touchscreens and tablets */
550 	{ }, 	/* Terminating entry */
551 };
552 
553 static struct input_device_id joydev_ids[] = {
554 	{
555 		.flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_ABSBIT,
556 		.evbit = { BIT(EV_ABS) },
557 		.absbit = { BIT(ABS_X) },
558 	},
559 	{
560 		.flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_ABSBIT,
561 		.evbit = { BIT(EV_ABS) },
562 		.absbit = { BIT(ABS_WHEEL) },
563 	},
564 	{
565 		.flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_ABSBIT,
566 		.evbit = { BIT(EV_ABS) },
567 		.absbit = { BIT(ABS_THROTTLE) },
568 	},
569 	{ }, 	/* Terminating entry */
570 };
571 
572 MODULE_DEVICE_TABLE(input, joydev_ids);
573 
574 static struct input_handler joydev_handler = {
575 	.event =	joydev_event,
576 	.connect =	joydev_connect,
577 	.disconnect =	joydev_disconnect,
578 	.fops =		&joydev_fops,
579 	.minor =	JOYDEV_MINOR_BASE,
580 	.name =		"joydev",
581 	.id_table =	joydev_ids,
582 	.blacklist = 	joydev_blacklist,
583 };
584 
585 static int __init joydev_init(void)
586 {
587 	input_register_handler(&joydev_handler);
588 	return 0;
589 }
590 
591 static void __exit joydev_exit(void)
592 {
593 	input_unregister_handler(&joydev_handler);
594 }
595 
596 module_init(joydev_init);
597 module_exit(joydev_exit);
598