xref: /linux/drivers/input/joydev.c (revision 36ca1195ad7f760a6af3814cb002bd3a3d4b4db1)
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 #include <linux/devfs_fs_kernel.h>
30 
31 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
32 MODULE_DESCRIPTION("Joystick device interfaces");
33 MODULE_SUPPORTED_DEVICE("input/js");
34 MODULE_LICENSE("GPL");
35 
36 #define JOYDEV_MINOR_BASE	0
37 #define JOYDEV_MINORS		16
38 #define JOYDEV_BUFFER_SIZE	64
39 
40 #define MSECS(t)	(1000 * ((t) / HZ) + 1000 * ((t) % HZ) / HZ)
41 
42 struct joydev {
43 	int exist;
44 	int open;
45 	int minor;
46 	char name[16];
47 	struct input_handle handle;
48 	wait_queue_head_t wait;
49 	struct list_head list;
50 	struct js_corr corr[ABS_MAX + 1];
51 	struct JS_DATA_SAVE_TYPE glue;
52 	int nabs;
53 	int nkey;
54 	__u16 keymap[KEY_MAX - BTN_MISC + 1];
55 	__u16 keypam[KEY_MAX - BTN_MISC + 1];
56 	__u8 absmap[ABS_MAX + 1];
57 	__u8 abspam[ABS_MAX + 1];
58 	__s16 abs[ABS_MAX + 1];
59 };
60 
61 struct joydev_list {
62 	struct js_event buffer[JOYDEV_BUFFER_SIZE];
63 	int head;
64 	int tail;
65 	int startup;
66 	struct fasync_struct *fasync;
67 	struct joydev *joydev;
68 	struct list_head node;
69 };
70 
71 static struct joydev *joydev_table[JOYDEV_MINORS];
72 
73 static int joydev_correct(int value, struct js_corr *corr)
74 {
75 	switch (corr->type) {
76 		case JS_CORR_NONE:
77 			break;
78 		case JS_CORR_BROKEN:
79 			value = value > corr->coef[0] ? (value < corr->coef[1] ? 0 :
80 				((corr->coef[3] * (value - corr->coef[1])) >> 14)) :
81 				((corr->coef[2] * (value - corr->coef[0])) >> 14);
82 			break;
83 		default:
84 			return 0;
85 	}
86 
87 	if (value < -32767) return -32767;
88 	if (value >  32767) return  32767;
89 
90 	return value;
91 }
92 
93 static void joydev_event(struct input_handle *handle, unsigned int type, unsigned int code, int value)
94 {
95 	struct joydev *joydev = handle->private;
96 	struct joydev_list *list;
97 	struct js_event event;
98 
99 	switch (type) {
100 
101 		case EV_KEY:
102 			if (code < BTN_MISC || value == 2) return;
103 			event.type = JS_EVENT_BUTTON;
104 			event.number = joydev->keymap[code - BTN_MISC];
105 			event.value = value;
106 			break;
107 
108 		case EV_ABS:
109 			event.type = JS_EVENT_AXIS;
110 			event.number = joydev->absmap[code];
111 			event.value = joydev_correct(value, joydev->corr + event.number);
112 			if (event.value == joydev->abs[event.number]) return;
113 			joydev->abs[event.number] = event.value;
114 			break;
115 
116 		default:
117 			return;
118 	}
119 
120 	event.time = MSECS(jiffies);
121 
122 	list_for_each_entry(list, &joydev->list, node) {
123 
124 		memcpy(list->buffer + list->head, &event, sizeof(struct js_event));
125 
126 		if (list->startup == joydev->nabs + joydev->nkey)
127 			if (list->tail == (list->head = (list->head + 1) & (JOYDEV_BUFFER_SIZE - 1)))
128 				list->startup = 0;
129 
130 		kill_fasync(&list->fasync, SIGIO, POLL_IN);
131 	}
132 
133 	wake_up_interruptible(&joydev->wait);
134 }
135 
136 static int joydev_fasync(int fd, struct file *file, int on)
137 {
138 	int retval;
139 	struct joydev_list *list = file->private_data;
140 	retval = fasync_helper(fd, file, on, &list->fasync);
141 	return retval < 0 ? retval : 0;
142 }
143 
144 static void joydev_free(struct joydev *joydev)
145 {
146 	joydev_table[joydev->minor] = NULL;
147 	kfree(joydev);
148 }
149 
150 static int joydev_release(struct inode * inode, struct file * file)
151 {
152 	struct joydev_list *list = file->private_data;
153 
154 	joydev_fasync(-1, file, 0);
155 
156 	list_del(&list->node);
157 
158 	if (!--list->joydev->open) {
159 		if (list->joydev->exist)
160 			input_close_device(&list->joydev->handle);
161 		else
162 			joydev_free(list->joydev);
163 	}
164 
165 	kfree(list);
166 	return 0;
167 }
168 
169 static int joydev_open(struct inode *inode, struct file *file)
170 {
171 	struct joydev_list *list;
172 	int i = iminor(inode) - JOYDEV_MINOR_BASE;
173 
174 	if (i >= JOYDEV_MINORS || !joydev_table[i])
175 		return -ENODEV;
176 
177 	if (!(list = kmalloc(sizeof(struct joydev_list), GFP_KERNEL)))
178 		return -ENOMEM;
179 	memset(list, 0, sizeof(struct joydev_list));
180 
181 	list->joydev = joydev_table[i];
182 	list_add_tail(&list->node, &joydev_table[i]->list);
183 	file->private_data = list;
184 
185 	if (!list->joydev->open++)
186 		if (list->joydev->exist)
187 			input_open_device(&list->joydev->handle);
188 
189 	return 0;
190 }
191 
192 static ssize_t joydev_write(struct file * file, const char __user * buffer, size_t count, loff_t *ppos)
193 {
194 	return -EINVAL;
195 }
196 
197 static ssize_t joydev_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
198 {
199 	struct joydev_list *list = file->private_data;
200 	struct joydev *joydev = list->joydev;
201 	struct input_dev *input = joydev->handle.dev;
202 	int retval = 0;
203 
204 	if (!list->joydev->exist)
205 		return -ENODEV;
206 
207 	if (count < sizeof(struct js_event))
208 		return -EINVAL;
209 
210 	if (count == sizeof(struct JS_DATA_TYPE)) {
211 
212 		struct JS_DATA_TYPE data;
213 		int i;
214 
215 		for (data.buttons = i = 0; i < 32 && i < joydev->nkey; i++)
216 			data.buttons |= test_bit(joydev->keypam[i], input->key) ? (1 << i) : 0;
217 		data.x = (joydev->abs[0] / 256 + 128) >> joydev->glue.JS_CORR.x;
218 		data.y = (joydev->abs[1] / 256 + 128) >> joydev->glue.JS_CORR.y;
219 
220 		if (copy_to_user(buf, &data, sizeof(struct JS_DATA_TYPE)))
221 			return -EFAULT;
222 
223 		list->startup = 0;
224 		list->tail = list->head;
225 
226 		return sizeof(struct JS_DATA_TYPE);
227 	}
228 
229 	if (list->startup == joydev->nabs + joydev->nkey
230 		&& list->head == list->tail && (file->f_flags & O_NONBLOCK))
231 			return -EAGAIN;
232 
233 	retval = wait_event_interruptible(list->joydev->wait,
234 		 			  !list->joydev->exist ||
235 					  list->startup < joydev->nabs + joydev->nkey ||
236 					  list->head != list->tail);
237 
238 	if (retval)
239 		return retval;
240 
241 	if (!list->joydev->exist)
242 		return -ENODEV;
243 
244 	while (list->startup < joydev->nabs + joydev->nkey && retval + sizeof(struct js_event) <= count) {
245 
246 		struct js_event event;
247 
248 		event.time = MSECS(jiffies);
249 
250 		if (list->startup < joydev->nkey) {
251 			event.type = JS_EVENT_BUTTON | JS_EVENT_INIT;
252 			event.number = list->startup;
253 			event.value = !!test_bit(joydev->keypam[event.number], input->key);
254 		} else {
255 			event.type = JS_EVENT_AXIS | JS_EVENT_INIT;
256 			event.number = list->startup - joydev->nkey;
257 			event.value = joydev->abs[event.number];
258 		}
259 
260 		if (copy_to_user(buf + retval, &event, sizeof(struct js_event)))
261 			return -EFAULT;
262 
263 		list->startup++;
264 		retval += sizeof(struct js_event);
265 	}
266 
267 	while (list->head != list->tail && retval + sizeof(struct js_event) <= count) {
268 
269 		if (copy_to_user(buf + retval, list->buffer + list->tail, sizeof(struct js_event)))
270 			return -EFAULT;
271 
272 		list->tail = (list->tail + 1) & (JOYDEV_BUFFER_SIZE - 1);
273 		retval += sizeof(struct js_event);
274 	}
275 
276 	return retval;
277 }
278 
279 /* No kernel lock - fine */
280 static unsigned int joydev_poll(struct file *file, poll_table *wait)
281 {
282 	struct joydev_list *list = file->private_data;
283 	poll_wait(file, &list->joydev->wait, wait);
284 	return ((list->head != list->tail || list->startup < list->joydev->nabs + list->joydev->nkey) ?
285 		(POLLIN | POLLRDNORM) : 0) | (list->joydev->exist ? 0 : (POLLHUP | POLLERR));
286 }
287 
288 static int joydev_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
289 {
290 	struct joydev_list *list = file->private_data;
291 	struct joydev *joydev = list->joydev;
292 	struct input_dev *dev = joydev->handle.dev;
293 	void __user *argp = (void __user *)arg;
294 	int i, j;
295 
296 	if (!joydev->exist) return -ENODEV;
297 
298 	switch (cmd) {
299 
300 		case JS_SET_CAL:
301 			return copy_from_user(&joydev->glue.JS_CORR, argp,
302 				sizeof(struct JS_DATA_TYPE)) ? -EFAULT : 0;
303 		case JS_GET_CAL:
304 			return copy_to_user(argp, &joydev->glue.JS_CORR,
305 				sizeof(struct JS_DATA_TYPE)) ? -EFAULT : 0;
306 		case JS_SET_TIMEOUT:
307 			return get_user(joydev->glue.JS_TIMEOUT, (int __user *) arg);
308 		case JS_GET_TIMEOUT:
309 			return put_user(joydev->glue.JS_TIMEOUT, (int __user *) arg);
310 		case JS_SET_TIMELIMIT:
311 			return get_user(joydev->glue.JS_TIMELIMIT, (long __user *) arg);
312 		case JS_GET_TIMELIMIT:
313 			return put_user(joydev->glue.JS_TIMELIMIT, (long __user *) arg);
314 		case JS_SET_ALL:
315 			return copy_from_user(&joydev->glue, argp,
316 						sizeof(struct JS_DATA_SAVE_TYPE)) ? -EFAULT : 0;
317 		case JS_GET_ALL:
318 			return copy_to_user(argp, &joydev->glue,
319 						sizeof(struct JS_DATA_SAVE_TYPE)) ? -EFAULT : 0;
320 
321 		case JSIOCGVERSION:
322 			return put_user(JS_VERSION, (__u32 __user *) arg);
323 		case JSIOCGAXES:
324 			return put_user(joydev->nabs, (__u8 __user *) arg);
325 		case JSIOCGBUTTONS:
326 			return put_user(joydev->nkey, (__u8 __user *) arg);
327 		case JSIOCSCORR:
328 			if (copy_from_user(joydev->corr, argp,
329 				      sizeof(struct js_corr) * joydev->nabs))
330 			    return -EFAULT;
331 			for (i = 0; i < joydev->nabs; i++) {
332 				j = joydev->abspam[i];
333 			        joydev->abs[i] = joydev_correct(dev->abs[j], joydev->corr + i);
334 			}
335 			return 0;
336 		case JSIOCGCORR:
337 			return copy_to_user(argp, joydev->corr,
338 						sizeof(struct js_corr) * joydev->nabs) ? -EFAULT : 0;
339 		case JSIOCSAXMAP:
340 			if (copy_from_user(joydev->abspam, argp, sizeof(__u8) * (ABS_MAX + 1)))
341 				return -EFAULT;
342 			for (i = 0; i < joydev->nabs; i++) {
343 				if (joydev->abspam[i] > ABS_MAX) return -EINVAL;
344 				joydev->absmap[joydev->abspam[i]] = i;
345 			}
346 			return 0;
347 		case JSIOCGAXMAP:
348 			return copy_to_user(argp, joydev->abspam,
349 						sizeof(__u8) * (ABS_MAX + 1)) ? -EFAULT : 0;
350 		case JSIOCSBTNMAP:
351 			if (copy_from_user(joydev->keypam, argp, sizeof(__u16) * (KEY_MAX - BTN_MISC + 1)))
352 				return -EFAULT;
353 			for (i = 0; i < joydev->nkey; i++) {
354 				if (joydev->keypam[i] > KEY_MAX || joydev->keypam[i] < BTN_MISC) return -EINVAL;
355 				joydev->keymap[joydev->keypam[i] - BTN_MISC] = i;
356 			}
357 			return 0;
358 		case JSIOCGBTNMAP:
359 			return copy_to_user(argp, joydev->keypam,
360 						sizeof(__u16) * (KEY_MAX - BTN_MISC + 1)) ? -EFAULT : 0;
361 		default:
362 			if ((cmd & ~(_IOC_SIZEMASK << _IOC_SIZESHIFT)) == JSIOCGNAME(0)) {
363 				int len;
364 				if (!dev->name) return 0;
365 				len = strlen(dev->name) + 1;
366 				if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd);
367 				if (copy_to_user(argp, dev->name, len)) return -EFAULT;
368 				return len;
369 			}
370 	}
371 	return -EINVAL;
372 }
373 
374 static struct file_operations joydev_fops = {
375 	.owner =	THIS_MODULE,
376 	.read =		joydev_read,
377 	.write =	joydev_write,
378 	.poll =		joydev_poll,
379 	.open =		joydev_open,
380 	.release =	joydev_release,
381 	.ioctl =	joydev_ioctl,
382 	.fasync =	joydev_fasync,
383 };
384 
385 static struct input_handle *joydev_connect(struct input_handler *handler, struct input_dev *dev, struct input_device_id *id)
386 {
387 	struct joydev *joydev;
388 	int i, j, t, minor;
389 
390 	for (minor = 0; minor < JOYDEV_MINORS && joydev_table[minor]; minor++);
391 	if (minor == JOYDEV_MINORS) {
392 		printk(KERN_ERR "joydev: no more free joydev devices\n");
393 		return NULL;
394 	}
395 
396 	if (!(joydev = kmalloc(sizeof(struct joydev), GFP_KERNEL)))
397 		return NULL;
398 	memset(joydev, 0, sizeof(struct joydev));
399 
400 	INIT_LIST_HEAD(&joydev->list);
401 	init_waitqueue_head(&joydev->wait);
402 
403 	joydev->minor = minor;
404 	joydev->exist = 1;
405 	joydev->handle.dev = dev;
406 	joydev->handle.name = joydev->name;
407 	joydev->handle.handler = handler;
408 	joydev->handle.private = joydev;
409 	sprintf(joydev->name, "js%d", minor);
410 
411 	for (i = 0; i < ABS_MAX + 1; i++)
412 		if (test_bit(i, dev->absbit)) {
413 			joydev->absmap[i] = joydev->nabs;
414 			joydev->abspam[joydev->nabs] = i;
415 			joydev->nabs++;
416 		}
417 
418 	for (i = BTN_JOYSTICK - BTN_MISC; i < KEY_MAX - BTN_MISC + 1; i++)
419 		if (test_bit(i + BTN_MISC, dev->keybit)) {
420 			joydev->keymap[i] = joydev->nkey;
421 			joydev->keypam[joydev->nkey] = i + BTN_MISC;
422 			joydev->nkey++;
423 		}
424 
425 	for (i = 0; i < BTN_JOYSTICK - BTN_MISC; i++)
426 		if (test_bit(i + BTN_MISC, dev->keybit)) {
427 			joydev->keymap[i] = joydev->nkey;
428 			joydev->keypam[joydev->nkey] = i + BTN_MISC;
429 			joydev->nkey++;
430 		}
431 
432 	for (i = 0; i < joydev->nabs; i++) {
433 		j = joydev->abspam[i];
434 		if (dev->absmax[j] == dev->absmin[j]) {
435 			joydev->corr[i].type = JS_CORR_NONE;
436 			joydev->abs[i] = dev->abs[j];
437 			continue;
438 		}
439 		joydev->corr[i].type = JS_CORR_BROKEN;
440 		joydev->corr[i].prec = dev->absfuzz[j];
441 		joydev->corr[i].coef[0] = (dev->absmax[j] + dev->absmin[j]) / 2 - dev->absflat[j];
442 		joydev->corr[i].coef[1] = (dev->absmax[j] + dev->absmin[j]) / 2 + dev->absflat[j];
443 		if (!(t = ((dev->absmax[j] - dev->absmin[j]) / 2 - 2 * dev->absflat[j])))
444 			continue;
445 		joydev->corr[i].coef[2] = (1 << 29) / t;
446 		joydev->corr[i].coef[3] = (1 << 29) / t;
447 
448 		joydev->abs[i] = joydev_correct(dev->abs[j], joydev->corr + i);
449 	}
450 
451 	joydev_table[minor] = joydev;
452 
453 	devfs_mk_cdev(MKDEV(INPUT_MAJOR, JOYDEV_MINOR_BASE + minor),
454 			S_IFCHR|S_IRUGO|S_IWUSR, "input/js%d", minor);
455 	class_simple_device_add(input_class,
456 				MKDEV(INPUT_MAJOR, JOYDEV_MINOR_BASE + minor),
457 				dev->dev, "js%d", minor);
458 
459 	return &joydev->handle;
460 }
461 
462 static void joydev_disconnect(struct input_handle *handle)
463 {
464 	struct joydev *joydev = handle->private;
465 	struct joydev_list *list;
466 
467 	class_simple_device_remove(MKDEV(INPUT_MAJOR, JOYDEV_MINOR_BASE + joydev->minor));
468 	devfs_remove("input/js%d", joydev->minor);
469 	joydev->exist = 0;
470 
471 	if (joydev->open) {
472 		input_close_device(handle);
473 		wake_up_interruptible(&joydev->wait);
474 		list_for_each_entry(list, &joydev->list, node)
475 			kill_fasync(&list->fasync, SIGIO, POLL_HUP);
476 	} else
477 		joydev_free(joydev);
478 }
479 
480 static struct input_device_id joydev_blacklist[] = {
481 	{
482 		.flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_KEYBIT,
483 		.evbit = { BIT(EV_KEY) },
484 		.keybit = { [LONG(BTN_TOUCH)] = BIT(BTN_TOUCH) },
485 	}, 	/* Avoid itouchpads, touchscreens and tablets */
486 	{ }, 	/* Terminating entry */
487 };
488 
489 static struct input_device_id joydev_ids[] = {
490 	{
491 		.flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_ABSBIT,
492 		.evbit = { BIT(EV_ABS) },
493 		.absbit = { BIT(ABS_X) },
494 	},
495 	{
496 		.flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_ABSBIT,
497 		.evbit = { BIT(EV_ABS) },
498 		.absbit = { BIT(ABS_WHEEL) },
499 	},
500 	{
501 		.flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_ABSBIT,
502 		.evbit = { BIT(EV_ABS) },
503 		.absbit = { BIT(ABS_THROTTLE) },
504 	},
505 	{ }, 	/* Terminating entry */
506 };
507 
508 MODULE_DEVICE_TABLE(input, joydev_ids);
509 
510 static struct input_handler joydev_handler = {
511 	.event =	joydev_event,
512 	.connect =	joydev_connect,
513 	.disconnect =	joydev_disconnect,
514 	.fops =		&joydev_fops,
515 	.minor =	JOYDEV_MINOR_BASE,
516 	.name =		"joydev",
517 	.id_table =	joydev_ids,
518 	.blacklist = 	joydev_blacklist,
519 };
520 
521 static int __init joydev_init(void)
522 {
523 	input_register_handler(&joydev_handler);
524 	return 0;
525 }
526 
527 static void __exit joydev_exit(void)
528 {
529 	input_unregister_handler(&joydev_handler);
530 }
531 
532 module_init(joydev_init);
533 module_exit(joydev_exit);
534