xref: /linux/drivers/input/joydev.c (revision 14b42963f64b98ab61fa9723c03d71aa5ef4f862)
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 	return value < -32767 ? -32767 : (value > 32767 ? 32767 : value);
85 }
86 
87 static void joydev_event(struct input_handle *handle, unsigned int type, unsigned int code, int value)
88 {
89 	struct joydev *joydev = handle->private;
90 	struct joydev_list *list;
91 	struct js_event event;
92 
93 	switch (type) {
94 
95 		case EV_KEY:
96 			if (code < BTN_MISC || value == 2)
97 				return;
98 			event.type = JS_EVENT_BUTTON;
99 			event.number = joydev->keymap[code - BTN_MISC];
100 			event.value = value;
101 			break;
102 
103 		case EV_ABS:
104 			event.type = JS_EVENT_AXIS;
105 			event.number = joydev->absmap[code];
106 			event.value = joydev_correct(value, joydev->corr + event.number);
107 			if (event.value == joydev->abs[event.number])
108 				return;
109 			joydev->abs[event.number] = event.value;
110 			break;
111 
112 		default:
113 			return;
114 	}
115 
116 	event.time = jiffies_to_msecs(jiffies);
117 
118 	list_for_each_entry(list, &joydev->list, node) {
119 
120 		memcpy(list->buffer + list->head, &event, sizeof(struct js_event));
121 
122 		if (list->startup == joydev->nabs + joydev->nkey)
123 			if (list->tail == (list->head = (list->head + 1) & (JOYDEV_BUFFER_SIZE - 1)))
124 				list->startup = 0;
125 
126 		kill_fasync(&list->fasync, SIGIO, POLL_IN);
127 	}
128 
129 	wake_up_interruptible(&joydev->wait);
130 }
131 
132 static int joydev_fasync(int fd, struct file *file, int on)
133 {
134 	int retval;
135 	struct joydev_list *list = file->private_data;
136 
137 	retval = fasync_helper(fd, file, on, &list->fasync);
138 
139 	return retval < 0 ? retval : 0;
140 }
141 
142 static void joydev_free(struct joydev *joydev)
143 {
144 	joydev_table[joydev->minor] = NULL;
145 	kfree(joydev);
146 }
147 
148 static int joydev_release(struct inode * inode, struct file * file)
149 {
150 	struct joydev_list *list = file->private_data;
151 
152 	joydev_fasync(-1, file, 0);
153 
154 	list_del(&list->node);
155 
156 	if (!--list->joydev->open) {
157 		if (list->joydev->exist)
158 			input_close_device(&list->joydev->handle);
159 		else
160 			joydev_free(list->joydev);
161 	}
162 
163 	kfree(list);
164 	return 0;
165 }
166 
167 static int joydev_open(struct inode *inode, struct file *file)
168 {
169 	struct joydev_list *list;
170 	int i = iminor(inode) - JOYDEV_MINOR_BASE;
171 
172 	if (i >= JOYDEV_MINORS || !joydev_table[i])
173 		return -ENODEV;
174 
175 	if (!(list = kzalloc(sizeof(struct joydev_list), GFP_KERNEL)))
176 		return -ENOMEM;
177 
178 	list->joydev = joydev_table[i];
179 	list_add_tail(&list->node, &joydev_table[i]->list);
180 	file->private_data = list;
181 
182 	if (!list->joydev->open++)
183 		if (list->joydev->exist)
184 			input_open_device(&list->joydev->handle);
185 
186 	return 0;
187 }
188 
189 static ssize_t joydev_write(struct file * file, const char __user * buffer, size_t count, loff_t *ppos)
190 {
191 	return -EINVAL;
192 }
193 
194 static ssize_t joydev_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
195 {
196 	struct joydev_list *list = file->private_data;
197 	struct joydev *joydev = list->joydev;
198 	struct input_dev *input = joydev->handle.dev;
199 	int retval = 0;
200 
201 	if (!list->joydev->exist)
202 		return -ENODEV;
203 
204 	if (count < sizeof(struct js_event))
205 		return -EINVAL;
206 
207 	if (count == sizeof(struct JS_DATA_TYPE)) {
208 
209 		struct JS_DATA_TYPE data;
210 		int i;
211 
212 		for (data.buttons = i = 0; i < 32 && i < joydev->nkey; i++)
213 			data.buttons |= test_bit(joydev->keypam[i], input->key) ? (1 << i) : 0;
214 		data.x = (joydev->abs[0] / 256 + 128) >> joydev->glue.JS_CORR.x;
215 		data.y = (joydev->abs[1] / 256 + 128) >> joydev->glue.JS_CORR.y;
216 
217 		if (copy_to_user(buf, &data, sizeof(struct JS_DATA_TYPE)))
218 			return -EFAULT;
219 
220 		list->startup = 0;
221 		list->tail = list->head;
222 
223 		return sizeof(struct JS_DATA_TYPE);
224 	}
225 
226 	if (list->startup == joydev->nabs + joydev->nkey &&
227 	    list->head == list->tail && (file->f_flags & O_NONBLOCK))
228 		return -EAGAIN;
229 
230 	retval = wait_event_interruptible(list->joydev->wait,
231 					  !list->joydev->exist ||
232 					  list->startup < joydev->nabs + joydev->nkey ||
233 					  list->head != list->tail);
234 
235 	if (retval)
236 		return retval;
237 
238 	if (!list->joydev->exist)
239 		return -ENODEV;
240 
241 	while (list->startup < joydev->nabs + joydev->nkey && retval + sizeof(struct js_event) <= count) {
242 
243 		struct js_event event;
244 
245 		event.time = jiffies_to_msecs(jiffies);
246 
247 		if (list->startup < joydev->nkey) {
248 			event.type = JS_EVENT_BUTTON | JS_EVENT_INIT;
249 			event.number = list->startup;
250 			event.value = !!test_bit(joydev->keypam[event.number], input->key);
251 		} else {
252 			event.type = JS_EVENT_AXIS | JS_EVENT_INIT;
253 			event.number = list->startup - joydev->nkey;
254 			event.value = joydev->abs[event.number];
255 		}
256 
257 		if (copy_to_user(buf + retval, &event, sizeof(struct js_event)))
258 			return -EFAULT;
259 
260 		list->startup++;
261 		retval += sizeof(struct js_event);
262 	}
263 
264 	while (list->head != list->tail && retval + sizeof(struct js_event) <= count) {
265 
266 		if (copy_to_user(buf + retval, list->buffer + list->tail, sizeof(struct js_event)))
267 			return -EFAULT;
268 
269 		list->tail = (list->tail + 1) & (JOYDEV_BUFFER_SIZE - 1);
270 		retval += sizeof(struct js_event);
271 	}
272 
273 	return retval;
274 }
275 
276 /* No kernel lock - fine */
277 static unsigned int joydev_poll(struct file *file, poll_table *wait)
278 {
279 	struct joydev_list *list = file->private_data;
280 
281 	poll_wait(file, &list->joydev->wait, wait);
282 	return ((list->head != list->tail || list->startup < list->joydev->nabs + list->joydev->nkey) ?
283 		(POLLIN | POLLRDNORM) : 0) | (list->joydev->exist ? 0 : (POLLHUP | POLLERR));
284 }
285 
286 static int joydev_ioctl_common(struct joydev *joydev, unsigned int cmd, void __user *argp)
287 {
288 	struct input_dev *dev = joydev->handle.dev;
289 	int i, j;
290 
291 	switch (cmd) {
292 
293 		case JS_SET_CAL:
294 			return copy_from_user(&joydev->glue.JS_CORR, argp,
295 				sizeof(joydev->glue.JS_CORR)) ? -EFAULT : 0;
296 
297 		case JS_GET_CAL:
298 			return copy_to_user(argp, &joydev->glue.JS_CORR,
299 				sizeof(joydev->glue.JS_CORR)) ? -EFAULT : 0;
300 
301 		case JS_SET_TIMEOUT:
302 			return get_user(joydev->glue.JS_TIMEOUT, (s32 __user *) argp);
303 
304 		case JS_GET_TIMEOUT:
305 			return put_user(joydev->glue.JS_TIMEOUT, (s32 __user *) argp);
306 
307 		case JSIOCGVERSION:
308 			return put_user(JS_VERSION, (__u32 __user *) argp);
309 
310 		case JSIOCGAXES:
311 			return put_user(joydev->nabs, (__u8 __user *) argp);
312 
313 		case JSIOCGBUTTONS:
314 			return put_user(joydev->nkey, (__u8 __user *) argp);
315 
316 		case JSIOCSCORR:
317 			if (copy_from_user(joydev->corr, argp,
318 				      sizeof(joydev->corr[0]) * joydev->nabs))
319 			    return -EFAULT;
320 			for (i = 0; i < joydev->nabs; i++) {
321 				j = joydev->abspam[i];
322 			        joydev->abs[i] = joydev_correct(dev->abs[j], joydev->corr + i);
323 			}
324 			return 0;
325 
326 		case JSIOCGCORR:
327 			return copy_to_user(argp, joydev->corr,
328 						sizeof(joydev->corr[0]) * joydev->nabs) ? -EFAULT : 0;
329 
330 		case JSIOCSAXMAP:
331 			if (copy_from_user(joydev->abspam, argp, sizeof(__u8) * (ABS_MAX + 1)))
332 				return -EFAULT;
333 			for (i = 0; i < joydev->nabs; i++) {
334 				if (joydev->abspam[i] > ABS_MAX)
335 					return -EINVAL;
336 				joydev->absmap[joydev->abspam[i]] = i;
337 			}
338 			return 0;
339 
340 		case JSIOCGAXMAP:
341 			return copy_to_user(argp, joydev->abspam,
342 						sizeof(__u8) * (ABS_MAX + 1)) ? -EFAULT : 0;
343 
344 		case JSIOCSBTNMAP:
345 			if (copy_from_user(joydev->keypam, argp, sizeof(__u16) * (KEY_MAX - BTN_MISC + 1)))
346 				return -EFAULT;
347 			for (i = 0; i < joydev->nkey; i++) {
348 				if (joydev->keypam[i] > KEY_MAX || joydev->keypam[i] < BTN_MISC)
349 					return -EINVAL;
350 				joydev->keymap[joydev->keypam[i] - BTN_MISC] = i;
351 			}
352 			return 0;
353 
354 		case JSIOCGBTNMAP:
355 			return copy_to_user(argp, joydev->keypam,
356 						sizeof(__u16) * (KEY_MAX - BTN_MISC + 1)) ? -EFAULT : 0;
357 
358 		default:
359 			if ((cmd & ~(_IOC_SIZEMASK << _IOC_SIZESHIFT)) == JSIOCGNAME(0)) {
360 				int len;
361 				if (!dev->name)
362 					return 0;
363 				len = strlen(dev->name) + 1;
364 				if (len > _IOC_SIZE(cmd))
365 					len = _IOC_SIZE(cmd);
366 				if (copy_to_user(argp, dev->name, len))
367 					return -EFAULT;
368 				return len;
369 			}
370 	}
371 	return -EINVAL;
372 }
373 
374 #ifdef CONFIG_COMPAT
375 static long joydev_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
376 {
377 	struct joydev_list *list = file->private_data;
378 	struct joydev *joydev = list->joydev;
379 	void __user *argp = (void __user *)arg;
380 	s32 tmp32;
381 	struct JS_DATA_SAVE_TYPE_32 ds32;
382 	int err;
383 
384 	if (!joydev->exist)
385 		return -ENODEV;
386 
387 	switch(cmd) {
388 	case JS_SET_TIMELIMIT:
389 		err = get_user(tmp32, (s32 __user *) arg);
390 		if (err == 0)
391 			joydev->glue.JS_TIMELIMIT = tmp32;
392 		break;
393 	case JS_GET_TIMELIMIT:
394 		tmp32 = joydev->glue.JS_TIMELIMIT;
395 		err = put_user(tmp32, (s32 __user *) arg);
396 		break;
397 
398 	case JS_SET_ALL:
399 		err = copy_from_user(&ds32, argp,
400 				     sizeof(ds32)) ? -EFAULT : 0;
401 		if (err == 0) {
402 			joydev->glue.JS_TIMEOUT    = ds32.JS_TIMEOUT;
403 			joydev->glue.BUSY          = ds32.BUSY;
404 			joydev->glue.JS_EXPIRETIME = ds32.JS_EXPIRETIME;
405 			joydev->glue.JS_TIMELIMIT  = ds32.JS_TIMELIMIT;
406 			joydev->glue.JS_SAVE       = ds32.JS_SAVE;
407 			joydev->glue.JS_CORR       = ds32.JS_CORR;
408 		}
409 		break;
410 
411 	case JS_GET_ALL:
412 		ds32.JS_TIMEOUT    = joydev->glue.JS_TIMEOUT;
413 		ds32.BUSY          = joydev->glue.BUSY;
414 		ds32.JS_EXPIRETIME = joydev->glue.JS_EXPIRETIME;
415 		ds32.JS_TIMELIMIT  = joydev->glue.JS_TIMELIMIT;
416 		ds32.JS_SAVE       = joydev->glue.JS_SAVE;
417 		ds32.JS_CORR       = joydev->glue.JS_CORR;
418 
419 		err = copy_to_user(argp, &ds32, sizeof(ds32)) ? -EFAULT : 0;
420 		break;
421 
422 	default:
423 		err = joydev_ioctl_common(joydev, cmd, argp);
424 	}
425 	return err;
426 }
427 #endif /* CONFIG_COMPAT */
428 
429 static int joydev_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
430 {
431 	struct joydev_list *list = file->private_data;
432 	struct joydev *joydev = list->joydev;
433 	void __user *argp = (void __user *)arg;
434 
435 	if (!joydev->exist)
436 		return -ENODEV;
437 
438 	switch(cmd) {
439 		case JS_SET_TIMELIMIT:
440 			return get_user(joydev->glue.JS_TIMELIMIT, (long __user *) arg);
441 		case JS_GET_TIMELIMIT:
442 			return put_user(joydev->glue.JS_TIMELIMIT, (long __user *) arg);
443 		case JS_SET_ALL:
444 			return copy_from_user(&joydev->glue, argp,
445 						sizeof(joydev->glue)) ? -EFAULT : 0;
446 		case JS_GET_ALL:
447 			return copy_to_user(argp, &joydev->glue,
448 						sizeof(joydev->glue)) ? -EFAULT : 0;
449 		default:
450 			return joydev_ioctl_common(joydev, cmd, argp);
451 	}
452 }
453 
454 static struct file_operations joydev_fops = {
455 	.owner =	THIS_MODULE,
456 	.read =		joydev_read,
457 	.write =	joydev_write,
458 	.poll =		joydev_poll,
459 	.open =		joydev_open,
460 	.release =	joydev_release,
461 	.ioctl =	joydev_ioctl,
462 #ifdef CONFIG_COMPAT
463 	.compat_ioctl =	joydev_compat_ioctl,
464 #endif
465 	.fasync =	joydev_fasync,
466 };
467 
468 static struct input_handle *joydev_connect(struct input_handler *handler, struct input_dev *dev, struct input_device_id *id)
469 {
470 	struct joydev *joydev;
471 	struct class_device *cdev;
472 	int i, j, t, minor;
473 
474 	for (minor = 0; minor < JOYDEV_MINORS && joydev_table[minor]; minor++);
475 	if (minor == JOYDEV_MINORS) {
476 		printk(KERN_ERR "joydev: no more free joydev devices\n");
477 		return NULL;
478 	}
479 
480 	if (!(joydev = kzalloc(sizeof(struct joydev), GFP_KERNEL)))
481 		return NULL;
482 
483 	INIT_LIST_HEAD(&joydev->list);
484 	init_waitqueue_head(&joydev->wait);
485 
486 	joydev->minor = minor;
487 	joydev->exist = 1;
488 	joydev->handle.dev = dev;
489 	joydev->handle.name = joydev->name;
490 	joydev->handle.handler = handler;
491 	joydev->handle.private = joydev;
492 	sprintf(joydev->name, "js%d", minor);
493 
494 	for (i = 0; i < ABS_MAX + 1; i++)
495 		if (test_bit(i, dev->absbit)) {
496 			joydev->absmap[i] = joydev->nabs;
497 			joydev->abspam[joydev->nabs] = i;
498 			joydev->nabs++;
499 		}
500 
501 	for (i = BTN_JOYSTICK - BTN_MISC; i < KEY_MAX - BTN_MISC + 1; i++)
502 		if (test_bit(i + BTN_MISC, dev->keybit)) {
503 			joydev->keymap[i] = joydev->nkey;
504 			joydev->keypam[joydev->nkey] = i + BTN_MISC;
505 			joydev->nkey++;
506 		}
507 
508 	for (i = 0; i < BTN_JOYSTICK - BTN_MISC; i++)
509 		if (test_bit(i + BTN_MISC, dev->keybit)) {
510 			joydev->keymap[i] = joydev->nkey;
511 			joydev->keypam[joydev->nkey] = i + BTN_MISC;
512 			joydev->nkey++;
513 		}
514 
515 	for (i = 0; i < joydev->nabs; i++) {
516 		j = joydev->abspam[i];
517 		if (dev->absmax[j] == dev->absmin[j]) {
518 			joydev->corr[i].type = JS_CORR_NONE;
519 			joydev->abs[i] = dev->abs[j];
520 			continue;
521 		}
522 		joydev->corr[i].type = JS_CORR_BROKEN;
523 		joydev->corr[i].prec = dev->absfuzz[j];
524 		joydev->corr[i].coef[0] = (dev->absmax[j] + dev->absmin[j]) / 2 - dev->absflat[j];
525 		joydev->corr[i].coef[1] = (dev->absmax[j] + dev->absmin[j]) / 2 + dev->absflat[j];
526 		if (!(t = ((dev->absmax[j] - dev->absmin[j]) / 2 - 2 * dev->absflat[j])))
527 			continue;
528 		joydev->corr[i].coef[2] = (1 << 29) / t;
529 		joydev->corr[i].coef[3] = (1 << 29) / t;
530 
531 		joydev->abs[i] = joydev_correct(dev->abs[j], joydev->corr + i);
532 	}
533 
534 	joydev_table[minor] = joydev;
535 
536 	cdev = class_device_create(&input_class, &dev->cdev,
537 			MKDEV(INPUT_MAJOR, JOYDEV_MINOR_BASE + minor),
538 			dev->cdev.dev, joydev->name);
539 
540 	/* temporary symlink to keep userspace happy */
541 	sysfs_create_link(&input_class.subsys.kset.kobj, &cdev->kobj,
542 			  joydev->name);
543 
544 	return &joydev->handle;
545 }
546 
547 static void joydev_disconnect(struct input_handle *handle)
548 {
549 	struct joydev *joydev = handle->private;
550 	struct joydev_list *list;
551 
552 	sysfs_remove_link(&input_class.subsys.kset.kobj, joydev->name);
553 	class_device_destroy(&input_class, MKDEV(INPUT_MAJOR, JOYDEV_MINOR_BASE + joydev->minor));
554 	joydev->exist = 0;
555 
556 	if (joydev->open) {
557 		input_close_device(handle);
558 		wake_up_interruptible(&joydev->wait);
559 		list_for_each_entry(list, &joydev->list, node)
560 			kill_fasync(&list->fasync, SIGIO, POLL_HUP);
561 	} else
562 		joydev_free(joydev);
563 }
564 
565 static struct input_device_id joydev_blacklist[] = {
566 	{
567 		.flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_KEYBIT,
568 		.evbit = { BIT(EV_KEY) },
569 		.keybit = { [LONG(BTN_TOUCH)] = BIT(BTN_TOUCH) },
570 	},	/* Avoid itouchpads, touchscreens and tablets */
571 	{ }	/* Terminating entry */
572 };
573 
574 static struct input_device_id joydev_ids[] = {
575 	{
576 		.flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_ABSBIT,
577 		.evbit = { BIT(EV_ABS) },
578 		.absbit = { BIT(ABS_X) },
579 	},
580 	{
581 		.flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_ABSBIT,
582 		.evbit = { BIT(EV_ABS) },
583 		.absbit = { BIT(ABS_WHEEL) },
584 	},
585 	{
586 		.flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_ABSBIT,
587 		.evbit = { BIT(EV_ABS) },
588 		.absbit = { BIT(ABS_THROTTLE) },
589 	},
590 	{ }	/* Terminating entry */
591 };
592 
593 MODULE_DEVICE_TABLE(input, joydev_ids);
594 
595 static struct input_handler joydev_handler = {
596 	.event =	joydev_event,
597 	.connect =	joydev_connect,
598 	.disconnect =	joydev_disconnect,
599 	.fops =		&joydev_fops,
600 	.minor =	JOYDEV_MINOR_BASE,
601 	.name =		"joydev",
602 	.id_table =	joydev_ids,
603 	.blacklist =	joydev_blacklist,
604 };
605 
606 static int __init joydev_init(void)
607 {
608 	input_register_handler(&joydev_handler);
609 	return 0;
610 }
611 
612 static void __exit joydev_exit(void)
613 {
614 	input_unregister_handler(&joydev_handler);
615 }
616 
617 module_init(joydev_init);
618 module_exit(joydev_exit);
619