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v4.6
   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 = memdup_user(argp, len);
 448	if (IS_ERR(abspam))
 449		return PTR_ERR(abspam);
 
 
 
 
 
 450
 451	for (i = 0; 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
 468static 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	len = min(len, sizeof(joydev->keypam));
 476
 477	/* Validate the map. */
 478	keypam = memdup_user(argp, len);
 479	if (IS_ERR(keypam))
 480		return PTR_ERR(keypam);
 
 
 
 
 
 481
 482	for (i = 0; i < joydev->nkey; i++) {
 483		if (keypam[i] > KEY_MAX || keypam[i] < BTN_MISC) {
 484			retval = -EINVAL;
 485			goto out;
 486		}
 487	}
 488
 489	memcpy(joydev->keypam, keypam, len);
 490
 491	for (i = 0; i < joydev->nkey; i++)
 492		joydev->keymap[keypam[i] - BTN_MISC] = i;
 493
 494 out:
 495	kfree(keypam);
 496	return retval;
 497}
 498
 499
 500static int joydev_ioctl_common(struct joydev *joydev,
 501				unsigned int cmd, void __user *argp)
 502{
 503	struct input_dev *dev = joydev->handle.dev;
 504	size_t len;
 505	int i;
 506	const char *name;
 507
 508	/* Process fixed-sized commands. */
 509	switch (cmd) {
 510
 511	case JS_SET_CAL:
 512		return copy_from_user(&joydev->glue.JS_CORR, argp,
 513				sizeof(joydev->glue.JS_CORR)) ? -EFAULT : 0;
 514
 515	case JS_GET_CAL:
 516		return copy_to_user(argp, &joydev->glue.JS_CORR,
 517				sizeof(joydev->glue.JS_CORR)) ? -EFAULT : 0;
 518
 519	case JS_SET_TIMEOUT:
 520		return get_user(joydev->glue.JS_TIMEOUT, (s32 __user *) argp);
 521
 522	case JS_GET_TIMEOUT:
 523		return put_user(joydev->glue.JS_TIMEOUT, (s32 __user *) argp);
 524
 525	case JSIOCGVERSION:
 526		return put_user(JS_VERSION, (__u32 __user *) argp);
 527
 528	case JSIOCGAXES:
 529		return put_user(joydev->nabs, (__u8 __user *) argp);
 530
 531	case JSIOCGBUTTONS:
 532		return put_user(joydev->nkey, (__u8 __user *) argp);
 533
 534	case JSIOCSCORR:
 535		if (copy_from_user(joydev->corr, argp,
 536			      sizeof(joydev->corr[0]) * joydev->nabs))
 537			return -EFAULT;
 538
 539		for (i = 0; i < joydev->nabs; i++) {
 540			int val = input_abs_get_val(dev, joydev->abspam[i]);
 541			joydev->abs[i] = joydev_correct(val, &joydev->corr[i]);
 542		}
 543		return 0;
 544
 545	case JSIOCGCORR:
 546		return copy_to_user(argp, joydev->corr,
 547			sizeof(joydev->corr[0]) * joydev->nabs) ? -EFAULT : 0;
 548
 549	}
 550
 551	/*
 552	 * Process variable-sized commands (the axis and button map commands
 553	 * are considered variable-sized to decouple them from the values of
 554	 * ABS_MAX and KEY_MAX).
 555	 */
 556	switch (cmd & ~IOCSIZE_MASK) {
 557
 558	case (JSIOCSAXMAP & ~IOCSIZE_MASK):
 559		return joydev_handle_JSIOCSAXMAP(joydev, argp, _IOC_SIZE(cmd));
 560
 561	case (JSIOCGAXMAP & ~IOCSIZE_MASK):
 562		len = min_t(size_t, _IOC_SIZE(cmd), sizeof(joydev->abspam));
 563		return copy_to_user(argp, joydev->abspam, len) ? -EFAULT : len;
 564
 565	case (JSIOCSBTNMAP & ~IOCSIZE_MASK):
 566		return joydev_handle_JSIOCSBTNMAP(joydev, argp, _IOC_SIZE(cmd));
 567
 568	case (JSIOCGBTNMAP & ~IOCSIZE_MASK):
 569		len = min_t(size_t, _IOC_SIZE(cmd), sizeof(joydev->keypam));
 570		return copy_to_user(argp, joydev->keypam, len) ? -EFAULT : len;
 571
 572	case JSIOCGNAME(0):
 573		name = dev->name;
 574		if (!name)
 575			return 0;
 576
 577		len = min_t(size_t, _IOC_SIZE(cmd), strlen(name) + 1);
 578		return copy_to_user(argp, name, len) ? -EFAULT : len;
 579	}
 580
 581	return -EINVAL;
 582}
 583
 584#ifdef CONFIG_COMPAT
 585static long joydev_compat_ioctl(struct file *file,
 586				unsigned int cmd, unsigned long arg)
 587{
 588	struct joydev_client *client = file->private_data;
 589	struct joydev *joydev = client->joydev;
 590	void __user *argp = (void __user *)arg;
 591	s32 tmp32;
 592	struct JS_DATA_SAVE_TYPE_32 ds32;
 593	int retval;
 594
 595	retval = mutex_lock_interruptible(&joydev->mutex);
 596	if (retval)
 597		return retval;
 598
 599	if (!joydev->exist) {
 600		retval = -ENODEV;
 601		goto out;
 602	}
 603
 604	switch (cmd) {
 605
 606	case JS_SET_TIMELIMIT:
 607		retval = get_user(tmp32, (s32 __user *) arg);
 608		if (retval == 0)
 609			joydev->glue.JS_TIMELIMIT = tmp32;
 610		break;
 611
 612	case JS_GET_TIMELIMIT:
 613		tmp32 = joydev->glue.JS_TIMELIMIT;
 614		retval = put_user(tmp32, (s32 __user *) arg);
 615		break;
 616
 617	case JS_SET_ALL:
 618		retval = copy_from_user(&ds32, argp,
 619					sizeof(ds32)) ? -EFAULT : 0;
 620		if (retval == 0) {
 621			joydev->glue.JS_TIMEOUT    = ds32.JS_TIMEOUT;
 622			joydev->glue.BUSY          = ds32.BUSY;
 623			joydev->glue.JS_EXPIRETIME = ds32.JS_EXPIRETIME;
 624			joydev->glue.JS_TIMELIMIT  = ds32.JS_TIMELIMIT;
 625			joydev->glue.JS_SAVE       = ds32.JS_SAVE;
 626			joydev->glue.JS_CORR       = ds32.JS_CORR;
 627		}
 628		break;
 629
 630	case JS_GET_ALL:
 631		ds32.JS_TIMEOUT    = joydev->glue.JS_TIMEOUT;
 632		ds32.BUSY          = joydev->glue.BUSY;
 633		ds32.JS_EXPIRETIME = joydev->glue.JS_EXPIRETIME;
 634		ds32.JS_TIMELIMIT  = joydev->glue.JS_TIMELIMIT;
 635		ds32.JS_SAVE       = joydev->glue.JS_SAVE;
 636		ds32.JS_CORR       = joydev->glue.JS_CORR;
 637
 638		retval = copy_to_user(argp, &ds32, sizeof(ds32)) ? -EFAULT : 0;
 639		break;
 640
 641	default:
 642		retval = joydev_ioctl_common(joydev, cmd, argp);
 643		break;
 644	}
 645
 646 out:
 647	mutex_unlock(&joydev->mutex);
 648	return retval;
 649}
 650#endif /* CONFIG_COMPAT */
 651
 652static long joydev_ioctl(struct file *file,
 653			 unsigned int cmd, unsigned long arg)
 654{
 655	struct joydev_client *client = file->private_data;
 656	struct joydev *joydev = client->joydev;
 657	void __user *argp = (void __user *)arg;
 658	int retval;
 659
 660	retval = mutex_lock_interruptible(&joydev->mutex);
 661	if (retval)
 662		return retval;
 663
 664	if (!joydev->exist) {
 665		retval = -ENODEV;
 666		goto out;
 667	}
 668
 669	switch (cmd) {
 670
 671	case JS_SET_TIMELIMIT:
 672		retval = get_user(joydev->glue.JS_TIMELIMIT,
 673				  (long __user *) arg);
 674		break;
 675
 676	case JS_GET_TIMELIMIT:
 677		retval = put_user(joydev->glue.JS_TIMELIMIT,
 678				  (long __user *) arg);
 679		break;
 680
 681	case JS_SET_ALL:
 682		retval = copy_from_user(&joydev->glue, argp,
 683					sizeof(joydev->glue)) ? -EFAULT : 0;
 684		break;
 685
 686	case JS_GET_ALL:
 687		retval = copy_to_user(argp, &joydev->glue,
 688				      sizeof(joydev->glue)) ? -EFAULT : 0;
 689		break;
 690
 691	default:
 692		retval = joydev_ioctl_common(joydev, cmd, argp);
 693		break;
 694	}
 695 out:
 696	mutex_unlock(&joydev->mutex);
 697	return retval;
 698}
 699
 700static const struct file_operations joydev_fops = {
 701	.owner		= THIS_MODULE,
 702	.read		= joydev_read,
 703	.poll		= joydev_poll,
 704	.open		= joydev_open,
 705	.release	= joydev_release,
 706	.unlocked_ioctl	= joydev_ioctl,
 707#ifdef CONFIG_COMPAT
 708	.compat_ioctl	= joydev_compat_ioctl,
 709#endif
 710	.fasync		= joydev_fasync,
 711	.llseek		= no_llseek,
 712};
 713
 
 
 
 
 
 
 
 
 
 
 
 
 
 714/*
 715 * Mark device non-existent. This disables writes, ioctls and
 716 * prevents new users from opening the device. Already posted
 717 * blocking reads will stay, however new ones will fail.
 718 */
 719static void joydev_mark_dead(struct joydev *joydev)
 720{
 721	mutex_lock(&joydev->mutex);
 722	joydev->exist = false;
 723	mutex_unlock(&joydev->mutex);
 724}
 725
 726static void joydev_cleanup(struct joydev *joydev)
 727{
 728	struct input_handle *handle = &joydev->handle;
 729
 730	joydev_mark_dead(joydev);
 731	joydev_hangup(joydev);
 732
 733	cdev_del(&joydev->cdev);
 734
 735	/* joydev is marked dead so no one else accesses joydev->open */
 736	if (joydev->open)
 737		input_close_device(handle);
 738}
 739
 740static bool joydev_dev_is_absolute_mouse(struct input_dev *dev)
 741{
 742	DECLARE_BITMAP(jd_scratch, KEY_CNT);
 743
 744	BUILD_BUG_ON(ABS_CNT > KEY_CNT || EV_CNT > KEY_CNT);
 745
 746	/*
 747	 * Virtualization (VMware, etc) and remote management (HP
 748	 * ILO2) solutions use absolute coordinates for their virtual
 749	 * pointing devices so that there is one-to-one relationship
 750	 * between pointer position on the host screen and virtual
 751	 * guest screen, and so their mice use ABS_X, ABS_Y and 3
 752	 * primary button events. This clashes with what joydev
 753	 * considers to be joysticks (a device with at minimum ABS_X
 754	 * axis).
 755	 *
 756	 * Here we are trying to separate absolute mice from
 757	 * joysticks. A device is, for joystick detection purposes,
 758	 * considered to be an absolute mouse if the following is
 759	 * true:
 760	 *
 761	 * 1) Event types are exactly EV_ABS, EV_KEY and EV_SYN.
 762	 * 2) Absolute events are exactly ABS_X and ABS_Y.
 763	 * 3) Keys are exactly BTN_LEFT, BTN_RIGHT and BTN_MIDDLE.
 764	 * 4) Device is not on "Amiga" bus.
 765	 */
 766
 767	bitmap_zero(jd_scratch, EV_CNT);
 768	__set_bit(EV_ABS, jd_scratch);
 769	__set_bit(EV_KEY, jd_scratch);
 770	__set_bit(EV_SYN, jd_scratch);
 771	if (!bitmap_equal(jd_scratch, dev->evbit, EV_CNT))
 772		return false;
 773
 774	bitmap_zero(jd_scratch, ABS_CNT);
 775	__set_bit(ABS_X, jd_scratch);
 776	__set_bit(ABS_Y, jd_scratch);
 777	if (!bitmap_equal(dev->absbit, jd_scratch, ABS_CNT))
 778		return false;
 779
 780	bitmap_zero(jd_scratch, KEY_CNT);
 781	__set_bit(BTN_LEFT, jd_scratch);
 782	__set_bit(BTN_RIGHT, jd_scratch);
 783	__set_bit(BTN_MIDDLE, jd_scratch);
 784
 785	if (!bitmap_equal(dev->keybit, jd_scratch, KEY_CNT))
 786		return false;
 787
 788	/*
 789	 * Amiga joystick (amijoy) historically uses left/middle/right
 790	 * button events.
 791	 */
 792	if (dev->id.bustype == BUS_AMIGA)
 793		return false;
 794
 795	return true;
 796}
 797
 798static bool joydev_match(struct input_handler *handler, struct input_dev *dev)
 799{
 800	/* Avoid touchpads and touchscreens */
 801	if (test_bit(EV_KEY, dev->evbit) && test_bit(BTN_TOUCH, dev->keybit))
 802		return false;
 803
 804	/* Avoid tablets, digitisers and similar devices */
 805	if (test_bit(EV_KEY, dev->evbit) && test_bit(BTN_DIGI, dev->keybit))
 806		return false;
 807
 808	/* Avoid absolute mice */
 809	if (joydev_dev_is_absolute_mouse(dev))
 810		return false;
 811
 812	return true;
 813}
 814
 815static int joydev_connect(struct input_handler *handler, struct input_dev *dev,
 816			  const struct input_device_id *id)
 817{
 818	struct joydev *joydev;
 819	int i, j, t, minor, dev_no;
 820	int error;
 821
 822	minor = input_get_new_minor(JOYDEV_MINOR_BASE, JOYDEV_MINORS, true);
 823	if (minor < 0) {
 824		error = minor;
 825		pr_err("failed to reserve new minor: %d\n", error);
 826		return error;
 
 
 827	}
 828
 829	joydev = kzalloc(sizeof(struct joydev), GFP_KERNEL);
 830	if (!joydev) {
 831		error = -ENOMEM;
 832		goto err_free_minor;
 833	}
 834
 835	INIT_LIST_HEAD(&joydev->client_list);
 836	spin_lock_init(&joydev->client_lock);
 837	mutex_init(&joydev->mutex);
 838	init_waitqueue_head(&joydev->wait);
 839	joydev->exist = true;
 840
 841	dev_no = minor;
 842	/* Normalize device number if it falls into legacy range */
 843	if (dev_no < JOYDEV_MINOR_BASE + JOYDEV_MINORS)
 844		dev_no -= JOYDEV_MINOR_BASE;
 845	dev_set_name(&joydev->dev, "js%d", dev_no);
 846
 847	joydev->handle.dev = input_get_device(dev);
 848	joydev->handle.name = dev_name(&joydev->dev);
 849	joydev->handle.handler = handler;
 850	joydev->handle.private = joydev;
 851
 852	for_each_set_bit(i, dev->absbit, ABS_CNT) {
 853		joydev->absmap[i] = joydev->nabs;
 854		joydev->abspam[joydev->nabs] = i;
 855		joydev->nabs++;
 856	}
 
 857
 858	for (i = BTN_JOYSTICK - BTN_MISC; i < KEY_MAX - BTN_MISC + 1; i++)
 859		if (test_bit(i + BTN_MISC, dev->keybit)) {
 860			joydev->keymap[i] = joydev->nkey;
 861			joydev->keypam[joydev->nkey] = i + BTN_MISC;
 862			joydev->nkey++;
 863		}
 864
 865	for (i = 0; i < BTN_JOYSTICK - BTN_MISC; i++)
 866		if (test_bit(i + BTN_MISC, dev->keybit)) {
 867			joydev->keymap[i] = joydev->nkey;
 868			joydev->keypam[joydev->nkey] = i + BTN_MISC;
 869			joydev->nkey++;
 870		}
 871
 872	for (i = 0; i < joydev->nabs; i++) {
 873		j = joydev->abspam[i];
 874		if (input_abs_get_max(dev, j) == input_abs_get_min(dev, j)) {
 875			joydev->corr[i].type = JS_CORR_NONE;
 876			joydev->abs[i] = input_abs_get_val(dev, j);
 877			continue;
 878		}
 879		joydev->corr[i].type = JS_CORR_BROKEN;
 880		joydev->corr[i].prec = input_abs_get_fuzz(dev, j);
 881
 882		t = (input_abs_get_max(dev, j) + input_abs_get_min(dev, j)) / 2;
 883		joydev->corr[i].coef[0] = t - input_abs_get_flat(dev, j);
 884		joydev->corr[i].coef[1] = t + input_abs_get_flat(dev, j);
 885
 886		t = (input_abs_get_max(dev, j) - input_abs_get_min(dev, j)) / 2
 887			- 2 * input_abs_get_flat(dev, j);
 888		if (t) {
 889			joydev->corr[i].coef[2] = (1 << 29) / t;
 890			joydev->corr[i].coef[3] = (1 << 29) / t;
 891
 892			joydev->abs[i] =
 893				joydev_correct(input_abs_get_val(dev, j),
 894					       joydev->corr + i);
 895		}
 896	}
 897
 898	joydev->dev.devt = MKDEV(INPUT_MAJOR, minor);
 899	joydev->dev.class = &input_class;
 900	joydev->dev.parent = &dev->dev;
 901	joydev->dev.release = joydev_free;
 902	device_initialize(&joydev->dev);
 903
 904	error = input_register_handle(&joydev->handle);
 905	if (error)
 906		goto err_free_joydev;
 907
 908	cdev_init(&joydev->cdev, &joydev_fops);
 909	joydev->cdev.kobj.parent = &joydev->dev.kobj;
 910	error = cdev_add(&joydev->cdev, joydev->dev.devt, 1);
 911	if (error)
 912		goto err_unregister_handle;
 913
 914	error = device_add(&joydev->dev);
 915	if (error)
 916		goto err_cleanup_joydev;
 917
 918	return 0;
 919
 920 err_cleanup_joydev:
 921	joydev_cleanup(joydev);
 922 err_unregister_handle:
 923	input_unregister_handle(&joydev->handle);
 924 err_free_joydev:
 925	put_device(&joydev->dev);
 926 err_free_minor:
 927	input_free_minor(minor);
 928	return error;
 929}
 930
 931static void joydev_disconnect(struct input_handle *handle)
 932{
 933	struct joydev *joydev = handle->private;
 934
 935	device_del(&joydev->dev);
 936	joydev_cleanup(joydev);
 937	input_free_minor(MINOR(joydev->dev.devt));
 938	input_unregister_handle(handle);
 939	put_device(&joydev->dev);
 940}
 941
 942static const struct input_device_id joydev_ids[] = {
 943	{
 944		.flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 945				INPUT_DEVICE_ID_MATCH_ABSBIT,
 946		.evbit = { BIT_MASK(EV_ABS) },
 947		.absbit = { BIT_MASK(ABS_X) },
 948	},
 949	{
 950		.flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 951				INPUT_DEVICE_ID_MATCH_ABSBIT,
 952		.evbit = { BIT_MASK(EV_ABS) },
 953		.absbit = { BIT_MASK(ABS_WHEEL) },
 954	},
 955	{
 956		.flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 957				INPUT_DEVICE_ID_MATCH_ABSBIT,
 958		.evbit = { BIT_MASK(EV_ABS) },
 959		.absbit = { BIT_MASK(ABS_THROTTLE) },
 960	},
 961	{
 962		.flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 963				INPUT_DEVICE_ID_MATCH_KEYBIT,
 964		.evbit = { BIT_MASK(EV_KEY) },
 965		.keybit = {[BIT_WORD(BTN_JOYSTICK)] = BIT_MASK(BTN_JOYSTICK) },
 966	},
 967	{
 968		.flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 969				INPUT_DEVICE_ID_MATCH_KEYBIT,
 970		.evbit = { BIT_MASK(EV_KEY) },
 971		.keybit = { [BIT_WORD(BTN_GAMEPAD)] = BIT_MASK(BTN_GAMEPAD) },
 972	},
 973	{
 974		.flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 975				INPUT_DEVICE_ID_MATCH_KEYBIT,
 976		.evbit = { BIT_MASK(EV_KEY) },
 977		.keybit = { [BIT_WORD(BTN_TRIGGER_HAPPY)] = BIT_MASK(BTN_TRIGGER_HAPPY) },
 978	},
 979	{ }	/* Terminating entry */
 980};
 981
 982MODULE_DEVICE_TABLE(input, joydev_ids);
 983
 984static struct input_handler joydev_handler = {
 985	.event		= joydev_event,
 986	.match		= joydev_match,
 987	.connect	= joydev_connect,
 988	.disconnect	= joydev_disconnect,
 989	.legacy_minors	= true,
 990	.minor		= JOYDEV_MINOR_BASE,
 991	.name		= "joydev",
 992	.id_table	= joydev_ids,
 993};
 994
 995static int __init joydev_init(void)
 996{
 997	return input_register_handler(&joydev_handler);
 998}
 999
1000static void __exit joydev_exit(void)
1001{
1002	input_unregister_handler(&joydev_handler);
1003}
1004
1005module_init(joydev_init);
1006module_exit(joydev_exit);
v3.1
  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 <asm/system.h>
 17#include <linux/delay.h>
 18#include <linux/errno.h>
 19#include <linux/joystick.h>
 20#include <linux/input.h>
 21#include <linux/kernel.h>
 22#include <linux/major.h>
 23#include <linux/sched.h>
 24#include <linux/slab.h>
 25#include <linux/mm.h>
 26#include <linux/miscdevice.h>
 27#include <linux/module.h>
 28#include <linux/poll.h>
 29#include <linux/init.h>
 30#include <linux/device.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	int minor;
 44	struct input_handle handle;
 45	wait_queue_head_t wait;
 46	struct list_head client_list;
 47	spinlock_t client_lock; /* protects client_list */
 48	struct mutex mutex;
 49	struct device dev;
 
 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 struct joydev *joydev_table[JOYDEV_MINORS];
 75static DEFINE_MUTEX(joydev_table_mutex);
 76
 77static int joydev_correct(int value, struct js_corr *corr)
 78{
 79	switch (corr->type) {
 80
 81	case JS_CORR_NONE:
 82		break;
 83
 84	case JS_CORR_BROKEN:
 85		value = value > corr->coef[0] ? (value < corr->coef[1] ? 0 :
 86			((corr->coef[3] * (value - corr->coef[1])) >> 14)) :
 87			((corr->coef[2] * (value - corr->coef[0])) >> 14);
 88		break;
 89
 90	default:
 91		return 0;
 92	}
 93
 94	return value < -32767 ? -32767 : (value > 32767 ? 32767 : value);
 95}
 96
 97static void joydev_pass_event(struct joydev_client *client,
 98			      struct js_event *event)
 99{
100	struct joydev *joydev = client->joydev;
101
102	/*
103	 * IRQs already disabled, just acquire the lock
104	 */
105	spin_lock(&client->buffer_lock);
106
107	client->buffer[client->head] = *event;
108
109	if (client->startup == joydev->nabs + joydev->nkey) {
110		client->head++;
111		client->head &= JOYDEV_BUFFER_SIZE - 1;
112		if (client->tail == client->head)
113			client->startup = 0;
114	}
115
116	spin_unlock(&client->buffer_lock);
117
118	kill_fasync(&client->fasync, SIGIO, POLL_IN);
119}
120
121static void joydev_event(struct input_handle *handle,
122			 unsigned int type, unsigned int code, int value)
123{
124	struct joydev *joydev = handle->private;
125	struct joydev_client *client;
126	struct js_event event;
127
128	switch (type) {
129
130	case EV_KEY:
131		if (code < BTN_MISC || value == 2)
132			return;
133		event.type = JS_EVENT_BUTTON;
134		event.number = joydev->keymap[code - BTN_MISC];
135		event.value = value;
136		break;
137
138	case EV_ABS:
139		event.type = JS_EVENT_AXIS;
140		event.number = joydev->absmap[code];
141		event.value = joydev_correct(value,
142					&joydev->corr[event.number]);
143		if (event.value == joydev->abs[event.number])
144			return;
145		joydev->abs[event.number] = event.value;
146		break;
147
148	default:
149		return;
150	}
151
152	event.time = jiffies_to_msecs(jiffies);
153
154	rcu_read_lock();
155	list_for_each_entry_rcu(client, &joydev->client_list, node)
156		joydev_pass_event(client, &event);
157	rcu_read_unlock();
158
159	wake_up_interruptible(&joydev->wait);
160}
161
162static int joydev_fasync(int fd, struct file *file, int on)
163{
164	struct joydev_client *client = file->private_data;
165
166	return fasync_helper(fd, file, on, &client->fasync);
167}
168
169static void joydev_free(struct device *dev)
170{
171	struct joydev *joydev = container_of(dev, struct joydev, dev);
172
173	input_put_device(joydev->handle.dev);
174	kfree(joydev);
175}
176
177static void joydev_attach_client(struct joydev *joydev,
178				 struct joydev_client *client)
179{
180	spin_lock(&joydev->client_lock);
181	list_add_tail_rcu(&client->node, &joydev->client_list);
182	spin_unlock(&joydev->client_lock);
183}
184
185static void joydev_detach_client(struct joydev *joydev,
186				 struct joydev_client *client)
187{
188	spin_lock(&joydev->client_lock);
189	list_del_rcu(&client->node);
190	spin_unlock(&joydev->client_lock);
191	synchronize_rcu();
192}
193
194static int joydev_open_device(struct joydev *joydev)
195{
196	int retval;
197
198	retval = mutex_lock_interruptible(&joydev->mutex);
199	if (retval)
200		return retval;
201
202	if (!joydev->exist)
203		retval = -ENODEV;
204	else if (!joydev->open++) {
205		retval = input_open_device(&joydev->handle);
206		if (retval)
207			joydev->open--;
208	}
209
210	mutex_unlock(&joydev->mutex);
211	return retval;
212}
213
214static void joydev_close_device(struct joydev *joydev)
215{
216	mutex_lock(&joydev->mutex);
217
218	if (joydev->exist && !--joydev->open)
219		input_close_device(&joydev->handle);
220
221	mutex_unlock(&joydev->mutex);
222}
223
224/*
225 * Wake up users waiting for IO so they can disconnect from
226 * dead device.
227 */
228static void joydev_hangup(struct joydev *joydev)
229{
230	struct joydev_client *client;
231
232	spin_lock(&joydev->client_lock);
233	list_for_each_entry(client, &joydev->client_list, node)
234		kill_fasync(&client->fasync, SIGIO, POLL_HUP);
235	spin_unlock(&joydev->client_lock);
236
237	wake_up_interruptible(&joydev->wait);
238}
239
240static int joydev_release(struct inode *inode, struct file *file)
241{
242	struct joydev_client *client = file->private_data;
243	struct joydev *joydev = client->joydev;
244
245	joydev_detach_client(joydev, client);
246	kfree(client);
247
248	joydev_close_device(joydev);
249	put_device(&joydev->dev);
250
251	return 0;
252}
253
254static int joydev_open(struct inode *inode, struct file *file)
255{
 
 
256	struct joydev_client *client;
257	struct joydev *joydev;
258	int i = iminor(inode) - JOYDEV_MINOR_BASE;
259	int error;
260
261	if (i >= JOYDEV_MINORS)
262		return -ENODEV;
263
264	error = mutex_lock_interruptible(&joydev_table_mutex);
265	if (error)
266		return error;
267	joydev = joydev_table[i];
268	if (joydev)
269		get_device(&joydev->dev);
270	mutex_unlock(&joydev_table_mutex);
271
272	if (!joydev)
273		return -ENODEV;
274
275	client = kzalloc(sizeof(struct joydev_client), GFP_KERNEL);
276	if (!client) {
277		error = -ENOMEM;
278		goto err_put_joydev;
279	}
280
281	spin_lock_init(&client->buffer_lock);
282	client->joydev = joydev;
283	joydev_attach_client(joydev, client);
284
285	error = joydev_open_device(joydev);
286	if (error)
287		goto err_free_client;
288
289	file->private_data = client;
290	nonseekable_open(inode, file);
291
292	return 0;
293
294 err_free_client:
295	joydev_detach_client(joydev, client);
296	kfree(client);
297 err_put_joydev:
298	put_device(&joydev->dev);
299	return error;
300}
301
302static int joydev_generate_startup_event(struct joydev_client *client,
303					 struct input_dev *input,
304					 struct js_event *event)
305{
306	struct joydev *joydev = client->joydev;
307	int have_event;
308
309	spin_lock_irq(&client->buffer_lock);
310
311	have_event = client->startup < joydev->nabs + joydev->nkey;
312
313	if (have_event) {
314
315		event->time = jiffies_to_msecs(jiffies);
316		if (client->startup < joydev->nkey) {
317			event->type = JS_EVENT_BUTTON | JS_EVENT_INIT;
318			event->number = client->startup;
319			event->value = !!test_bit(joydev->keypam[event->number],
320						  input->key);
321		} else {
322			event->type = JS_EVENT_AXIS | JS_EVENT_INIT;
323			event->number = client->startup - joydev->nkey;
324			event->value = joydev->abs[event->number];
325		}
326		client->startup++;
327	}
328
329	spin_unlock_irq(&client->buffer_lock);
330
331	return have_event;
332}
333
334static int joydev_fetch_next_event(struct joydev_client *client,
335				   struct js_event *event)
336{
337	int have_event;
338
339	spin_lock_irq(&client->buffer_lock);
340
341	have_event = client->head != client->tail;
342	if (have_event) {
343		*event = client->buffer[client->tail++];
344		client->tail &= JOYDEV_BUFFER_SIZE - 1;
345	}
346
347	spin_unlock_irq(&client->buffer_lock);
348
349	return have_event;
350}
351
352/*
353 * Old joystick interface
354 */
355static ssize_t joydev_0x_read(struct joydev_client *client,
356			      struct input_dev *input,
357			      char __user *buf)
358{
359	struct joydev *joydev = client->joydev;
360	struct JS_DATA_TYPE data;
361	int i;
362
363	spin_lock_irq(&input->event_lock);
364
365	/*
366	 * Get device state
367	 */
368	for (data.buttons = i = 0; i < 32 && i < joydev->nkey; i++)
369		data.buttons |=
370			test_bit(joydev->keypam[i], input->key) ? (1 << i) : 0;
371	data.x = (joydev->abs[0] / 256 + 128) >> joydev->glue.JS_CORR.x;
372	data.y = (joydev->abs[1] / 256 + 128) >> joydev->glue.JS_CORR.y;
373
374	/*
375	 * Reset reader's event queue
376	 */
377	spin_lock(&client->buffer_lock);
378	client->startup = 0;
379	client->tail = client->head;
380	spin_unlock(&client->buffer_lock);
381
382	spin_unlock_irq(&input->event_lock);
383
384	if (copy_to_user(buf, &data, sizeof(struct JS_DATA_TYPE)))
385		return -EFAULT;
386
387	return sizeof(struct JS_DATA_TYPE);
388}
389
390static inline int joydev_data_pending(struct joydev_client *client)
391{
392	struct joydev *joydev = client->joydev;
393
394	return client->startup < joydev->nabs + joydev->nkey ||
395		client->head != client->tail;
396}
397
398static ssize_t joydev_read(struct file *file, char __user *buf,
399			   size_t count, loff_t *ppos)
400{
401	struct joydev_client *client = file->private_data;
402	struct joydev *joydev = client->joydev;
403	struct input_dev *input = joydev->handle.dev;
404	struct js_event event;
405	int retval;
406
407	if (!joydev->exist)
408		return -ENODEV;
409
410	if (count < sizeof(struct js_event))
411		return -EINVAL;
412
413	if (count == sizeof(struct JS_DATA_TYPE))
414		return joydev_0x_read(client, input, buf);
415
416	if (!joydev_data_pending(client) && (file->f_flags & O_NONBLOCK))
417		return -EAGAIN;
418
419	retval = wait_event_interruptible(joydev->wait,
420			!joydev->exist || joydev_data_pending(client));
421	if (retval)
422		return retval;
423
424	if (!joydev->exist)
425		return -ENODEV;
426
427	while (retval + sizeof(struct js_event) <= count &&
428	       joydev_generate_startup_event(client, input, &event)) {
429
430		if (copy_to_user(buf + retval, &event, sizeof(struct js_event)))
431			return -EFAULT;
432
433		retval += sizeof(struct js_event);
434	}
435
436	while (retval + sizeof(struct js_event) <= count &&
437	       joydev_fetch_next_event(client, &event)) {
438
439		if (copy_to_user(buf + retval, &event, sizeof(struct js_event)))
440			return -EFAULT;
441
442		retval += sizeof(struct js_event);
443	}
444
445	return retval;
446}
447
448/* No kernel lock - fine */
449static unsigned int joydev_poll(struct file *file, poll_table *wait)
450{
451	struct joydev_client *client = file->private_data;
452	struct joydev *joydev = client->joydev;
453
454	poll_wait(file, &joydev->wait, wait);
455	return (joydev_data_pending(client) ? (POLLIN | POLLRDNORM) : 0) |
456		(joydev->exist ?  0 : (POLLHUP | POLLERR));
457}
458
459static int joydev_handle_JSIOCSAXMAP(struct joydev *joydev,
460				     void __user *argp, size_t len)
461{
462	__u8 *abspam;
463	int i;
464	int retval = 0;
465
466	len = min(len, sizeof(joydev->abspam));
467
468	/* Validate the map. */
469	abspam = kmalloc(len, GFP_KERNEL);
470	if (!abspam)
471		return -ENOMEM;
472
473	if (copy_from_user(abspam, argp, len)) {
474		retval = -EFAULT;
475		goto out;
476	}
477
478	for (i = 0; i < joydev->nabs; i++) {
479		if (abspam[i] > ABS_MAX) {
480			retval = -EINVAL;
481			goto out;
482		}
483	}
484
485	memcpy(joydev->abspam, abspam, len);
486
487	for (i = 0; i < joydev->nabs; i++)
488		joydev->absmap[joydev->abspam[i]] = i;
489
490 out:
491	kfree(abspam);
492	return retval;
493}
494
495static int joydev_handle_JSIOCSBTNMAP(struct joydev *joydev,
496				      void __user *argp, size_t len)
497{
498	__u16 *keypam;
499	int i;
500	int retval = 0;
501
502	len = min(len, sizeof(joydev->keypam));
503
504	/* Validate the map. */
505	keypam = kmalloc(len, GFP_KERNEL);
506	if (!keypam)
507		return -ENOMEM;
508
509	if (copy_from_user(keypam, argp, len)) {
510		retval = -EFAULT;
511		goto out;
512	}
513
514	for (i = 0; i < joydev->nkey; i++) {
515		if (keypam[i] > KEY_MAX || keypam[i] < BTN_MISC) {
516			retval = -EINVAL;
517			goto out;
518		}
519	}
520
521	memcpy(joydev->keypam, keypam, len);
522
523	for (i = 0; i < joydev->nkey; i++)
524		joydev->keymap[keypam[i] - BTN_MISC] = i;
525
526 out:
527	kfree(keypam);
528	return retval;
529}
530
531
532static int joydev_ioctl_common(struct joydev *joydev,
533				unsigned int cmd, void __user *argp)
534{
535	struct input_dev *dev = joydev->handle.dev;
536	size_t len;
537	int i;
538	const char *name;
539
540	/* Process fixed-sized commands. */
541	switch (cmd) {
542
543	case JS_SET_CAL:
544		return copy_from_user(&joydev->glue.JS_CORR, argp,
545				sizeof(joydev->glue.JS_CORR)) ? -EFAULT : 0;
546
547	case JS_GET_CAL:
548		return copy_to_user(argp, &joydev->glue.JS_CORR,
549				sizeof(joydev->glue.JS_CORR)) ? -EFAULT : 0;
550
551	case JS_SET_TIMEOUT:
552		return get_user(joydev->glue.JS_TIMEOUT, (s32 __user *) argp);
553
554	case JS_GET_TIMEOUT:
555		return put_user(joydev->glue.JS_TIMEOUT, (s32 __user *) argp);
556
557	case JSIOCGVERSION:
558		return put_user(JS_VERSION, (__u32 __user *) argp);
559
560	case JSIOCGAXES:
561		return put_user(joydev->nabs, (__u8 __user *) argp);
562
563	case JSIOCGBUTTONS:
564		return put_user(joydev->nkey, (__u8 __user *) argp);
565
566	case JSIOCSCORR:
567		if (copy_from_user(joydev->corr, argp,
568			      sizeof(joydev->corr[0]) * joydev->nabs))
569			return -EFAULT;
570
571		for (i = 0; i < joydev->nabs; i++) {
572			int val = input_abs_get_val(dev, joydev->abspam[i]);
573			joydev->abs[i] = joydev_correct(val, &joydev->corr[i]);
574		}
575		return 0;
576
577	case JSIOCGCORR:
578		return copy_to_user(argp, joydev->corr,
579			sizeof(joydev->corr[0]) * joydev->nabs) ? -EFAULT : 0;
580
581	}
582
583	/*
584	 * Process variable-sized commands (the axis and button map commands
585	 * are considered variable-sized to decouple them from the values of
586	 * ABS_MAX and KEY_MAX).
587	 */
588	switch (cmd & ~IOCSIZE_MASK) {
589
590	case (JSIOCSAXMAP & ~IOCSIZE_MASK):
591		return joydev_handle_JSIOCSAXMAP(joydev, argp, _IOC_SIZE(cmd));
592
593	case (JSIOCGAXMAP & ~IOCSIZE_MASK):
594		len = min_t(size_t, _IOC_SIZE(cmd), sizeof(joydev->abspam));
595		return copy_to_user(argp, joydev->abspam, len) ? -EFAULT : len;
596
597	case (JSIOCSBTNMAP & ~IOCSIZE_MASK):
598		return joydev_handle_JSIOCSBTNMAP(joydev, argp, _IOC_SIZE(cmd));
599
600	case (JSIOCGBTNMAP & ~IOCSIZE_MASK):
601		len = min_t(size_t, _IOC_SIZE(cmd), sizeof(joydev->keypam));
602		return copy_to_user(argp, joydev->keypam, len) ? -EFAULT : len;
603
604	case JSIOCGNAME(0):
605		name = dev->name;
606		if (!name)
607			return 0;
608
609		len = min_t(size_t, _IOC_SIZE(cmd), strlen(name) + 1);
610		return copy_to_user(argp, name, len) ? -EFAULT : len;
611	}
612
613	return -EINVAL;
614}
615
616#ifdef CONFIG_COMPAT
617static long joydev_compat_ioctl(struct file *file,
618				unsigned int cmd, unsigned long arg)
619{
620	struct joydev_client *client = file->private_data;
621	struct joydev *joydev = client->joydev;
622	void __user *argp = (void __user *)arg;
623	s32 tmp32;
624	struct JS_DATA_SAVE_TYPE_32 ds32;
625	int retval;
626
627	retval = mutex_lock_interruptible(&joydev->mutex);
628	if (retval)
629		return retval;
630
631	if (!joydev->exist) {
632		retval = -ENODEV;
633		goto out;
634	}
635
636	switch (cmd) {
637
638	case JS_SET_TIMELIMIT:
639		retval = get_user(tmp32, (s32 __user *) arg);
640		if (retval == 0)
641			joydev->glue.JS_TIMELIMIT = tmp32;
642		break;
643
644	case JS_GET_TIMELIMIT:
645		tmp32 = joydev->glue.JS_TIMELIMIT;
646		retval = put_user(tmp32, (s32 __user *) arg);
647		break;
648
649	case JS_SET_ALL:
650		retval = copy_from_user(&ds32, argp,
651					sizeof(ds32)) ? -EFAULT : 0;
652		if (retval == 0) {
653			joydev->glue.JS_TIMEOUT    = ds32.JS_TIMEOUT;
654			joydev->glue.BUSY          = ds32.BUSY;
655			joydev->glue.JS_EXPIRETIME = ds32.JS_EXPIRETIME;
656			joydev->glue.JS_TIMELIMIT  = ds32.JS_TIMELIMIT;
657			joydev->glue.JS_SAVE       = ds32.JS_SAVE;
658			joydev->glue.JS_CORR       = ds32.JS_CORR;
659		}
660		break;
661
662	case JS_GET_ALL:
663		ds32.JS_TIMEOUT    = joydev->glue.JS_TIMEOUT;
664		ds32.BUSY          = joydev->glue.BUSY;
665		ds32.JS_EXPIRETIME = joydev->glue.JS_EXPIRETIME;
666		ds32.JS_TIMELIMIT  = joydev->glue.JS_TIMELIMIT;
667		ds32.JS_SAVE       = joydev->glue.JS_SAVE;
668		ds32.JS_CORR       = joydev->glue.JS_CORR;
669
670		retval = copy_to_user(argp, &ds32, sizeof(ds32)) ? -EFAULT : 0;
671		break;
672
673	default:
674		retval = joydev_ioctl_common(joydev, cmd, argp);
675		break;
676	}
677
678 out:
679	mutex_unlock(&joydev->mutex);
680	return retval;
681}
682#endif /* CONFIG_COMPAT */
683
684static long joydev_ioctl(struct file *file,
685			 unsigned int cmd, unsigned long arg)
686{
687	struct joydev_client *client = file->private_data;
688	struct joydev *joydev = client->joydev;
689	void __user *argp = (void __user *)arg;
690	int retval;
691
692	retval = mutex_lock_interruptible(&joydev->mutex);
693	if (retval)
694		return retval;
695
696	if (!joydev->exist) {
697		retval = -ENODEV;
698		goto out;
699	}
700
701	switch (cmd) {
702
703	case JS_SET_TIMELIMIT:
704		retval = get_user(joydev->glue.JS_TIMELIMIT,
705				  (long __user *) arg);
706		break;
707
708	case JS_GET_TIMELIMIT:
709		retval = put_user(joydev->glue.JS_TIMELIMIT,
710				  (long __user *) arg);
711		break;
712
713	case JS_SET_ALL:
714		retval = copy_from_user(&joydev->glue, argp,
715					sizeof(joydev->glue)) ? -EFAULT: 0;
716		break;
717
718	case JS_GET_ALL:
719		retval = copy_to_user(argp, &joydev->glue,
720				      sizeof(joydev->glue)) ? -EFAULT : 0;
721		break;
722
723	default:
724		retval = joydev_ioctl_common(joydev, cmd, argp);
725		break;
726	}
727 out:
728	mutex_unlock(&joydev->mutex);
729	return retval;
730}
731
732static const struct file_operations joydev_fops = {
733	.owner		= THIS_MODULE,
734	.read		= joydev_read,
735	.poll		= joydev_poll,
736	.open		= joydev_open,
737	.release	= joydev_release,
738	.unlocked_ioctl	= joydev_ioctl,
739#ifdef CONFIG_COMPAT
740	.compat_ioctl	= joydev_compat_ioctl,
741#endif
742	.fasync		= joydev_fasync,
743	.llseek		= no_llseek,
744};
745
746static int joydev_install_chrdev(struct joydev *joydev)
747{
748	joydev_table[joydev->minor] = joydev;
749	return 0;
750}
751
752static void joydev_remove_chrdev(struct joydev *joydev)
753{
754	mutex_lock(&joydev_table_mutex);
755	joydev_table[joydev->minor] = NULL;
756	mutex_unlock(&joydev_table_mutex);
757}
758
759/*
760 * Mark device non-existent. This disables writes, ioctls and
761 * prevents new users from opening the device. Already posted
762 * blocking reads will stay, however new ones will fail.
763 */
764static void joydev_mark_dead(struct joydev *joydev)
765{
766	mutex_lock(&joydev->mutex);
767	joydev->exist = false;
768	mutex_unlock(&joydev->mutex);
769}
770
771static void joydev_cleanup(struct joydev *joydev)
772{
773	struct input_handle *handle = &joydev->handle;
774
775	joydev_mark_dead(joydev);
776	joydev_hangup(joydev);
777	joydev_remove_chrdev(joydev);
 
778
779	/* joydev is marked dead so no one else accesses joydev->open */
780	if (joydev->open)
781		input_close_device(handle);
782}
783
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
784
785static bool joydev_match(struct input_handler *handler, struct input_dev *dev)
786{
787	/* Avoid touchpads and touchscreens */
788	if (test_bit(EV_KEY, dev->evbit) && test_bit(BTN_TOUCH, dev->keybit))
789		return false;
790
791	/* Avoid tablets, digitisers and similar devices */
792	if (test_bit(EV_KEY, dev->evbit) && test_bit(BTN_DIGI, dev->keybit))
793		return false;
794
 
 
 
 
795	return true;
796}
797
798static int joydev_connect(struct input_handler *handler, struct input_dev *dev,
799			  const struct input_device_id *id)
800{
801	struct joydev *joydev;
802	int i, j, t, minor;
803	int error;
804
805	for (minor = 0; minor < JOYDEV_MINORS; minor++)
806		if (!joydev_table[minor])
807			break;
808
809	if (minor == JOYDEV_MINORS) {
810		pr_err("no more free joydev devices\n");
811		return -ENFILE;
812	}
813
814	joydev = kzalloc(sizeof(struct joydev), GFP_KERNEL);
815	if (!joydev)
816		return -ENOMEM;
 
 
817
818	INIT_LIST_HEAD(&joydev->client_list);
819	spin_lock_init(&joydev->client_lock);
820	mutex_init(&joydev->mutex);
821	init_waitqueue_head(&joydev->wait);
 
822
823	dev_set_name(&joydev->dev, "js%d", minor);
824	joydev->exist = true;
825	joydev->minor = minor;
 
 
826
827	joydev->handle.dev = input_get_device(dev);
828	joydev->handle.name = dev_name(&joydev->dev);
829	joydev->handle.handler = handler;
830	joydev->handle.private = joydev;
831
832	for (i = 0; i < ABS_CNT; i++)
833		if (test_bit(i, dev->absbit)) {
834			joydev->absmap[i] = joydev->nabs;
835			joydev->abspam[joydev->nabs] = i;
836			joydev->nabs++;
837		}
838
839	for (i = BTN_JOYSTICK - BTN_MISC; i < KEY_MAX - BTN_MISC + 1; i++)
840		if (test_bit(i + BTN_MISC, dev->keybit)) {
841			joydev->keymap[i] = joydev->nkey;
842			joydev->keypam[joydev->nkey] = i + BTN_MISC;
843			joydev->nkey++;
844		}
845
846	for (i = 0; i < BTN_JOYSTICK - BTN_MISC; i++)
847		if (test_bit(i + BTN_MISC, dev->keybit)) {
848			joydev->keymap[i] = joydev->nkey;
849			joydev->keypam[joydev->nkey] = i + BTN_MISC;
850			joydev->nkey++;
851		}
852
853	for (i = 0; i < joydev->nabs; i++) {
854		j = joydev->abspam[i];
855		if (input_abs_get_max(dev, j) == input_abs_get_min(dev, j)) {
856			joydev->corr[i].type = JS_CORR_NONE;
857			joydev->abs[i] = input_abs_get_val(dev, j);
858			continue;
859		}
860		joydev->corr[i].type = JS_CORR_BROKEN;
861		joydev->corr[i].prec = input_abs_get_fuzz(dev, j);
862
863		t = (input_abs_get_max(dev, j) + input_abs_get_min(dev, j)) / 2;
864		joydev->corr[i].coef[0] = t - input_abs_get_flat(dev, j);
865		joydev->corr[i].coef[1] = t + input_abs_get_flat(dev, j);
866
867		t = (input_abs_get_max(dev, j) - input_abs_get_min(dev, j)) / 2
868			- 2 * input_abs_get_flat(dev, j);
869		if (t) {
870			joydev->corr[i].coef[2] = (1 << 29) / t;
871			joydev->corr[i].coef[3] = (1 << 29) / t;
872
873			joydev->abs[i] =
874				joydev_correct(input_abs_get_val(dev, j),
875					       joydev->corr + i);
876		}
877	}
878
879	joydev->dev.devt = MKDEV(INPUT_MAJOR, JOYDEV_MINOR_BASE + minor);
880	joydev->dev.class = &input_class;
881	joydev->dev.parent = &dev->dev;
882	joydev->dev.release = joydev_free;
883	device_initialize(&joydev->dev);
884
885	error = input_register_handle(&joydev->handle);
886	if (error)
887		goto err_free_joydev;
888
889	error = joydev_install_chrdev(joydev);
 
 
890	if (error)
891		goto err_unregister_handle;
892
893	error = device_add(&joydev->dev);
894	if (error)
895		goto err_cleanup_joydev;
896
897	return 0;
898
899 err_cleanup_joydev:
900	joydev_cleanup(joydev);
901 err_unregister_handle:
902	input_unregister_handle(&joydev->handle);
903 err_free_joydev:
904	put_device(&joydev->dev);
 
 
905	return error;
906}
907
908static void joydev_disconnect(struct input_handle *handle)
909{
910	struct joydev *joydev = handle->private;
911
912	device_del(&joydev->dev);
913	joydev_cleanup(joydev);
 
914	input_unregister_handle(handle);
915	put_device(&joydev->dev);
916}
917
918static const struct input_device_id joydev_ids[] = {
919	{
920		.flags = INPUT_DEVICE_ID_MATCH_EVBIT |
921				INPUT_DEVICE_ID_MATCH_ABSBIT,
922		.evbit = { BIT_MASK(EV_ABS) },
923		.absbit = { BIT_MASK(ABS_X) },
924	},
925	{
926		.flags = INPUT_DEVICE_ID_MATCH_EVBIT |
927				INPUT_DEVICE_ID_MATCH_ABSBIT,
928		.evbit = { BIT_MASK(EV_ABS) },
929		.absbit = { BIT_MASK(ABS_WHEEL) },
930	},
931	{
932		.flags = INPUT_DEVICE_ID_MATCH_EVBIT |
933				INPUT_DEVICE_ID_MATCH_ABSBIT,
934		.evbit = { BIT_MASK(EV_ABS) },
935		.absbit = { BIT_MASK(ABS_THROTTLE) },
936	},
937	{
938		.flags = INPUT_DEVICE_ID_MATCH_EVBIT |
939				INPUT_DEVICE_ID_MATCH_KEYBIT,
940		.evbit = { BIT_MASK(EV_KEY) },
941		.keybit = {[BIT_WORD(BTN_JOYSTICK)] = BIT_MASK(BTN_JOYSTICK) },
942	},
943	{
944		.flags = INPUT_DEVICE_ID_MATCH_EVBIT |
945				INPUT_DEVICE_ID_MATCH_KEYBIT,
946		.evbit = { BIT_MASK(EV_KEY) },
947		.keybit = { [BIT_WORD(BTN_GAMEPAD)] = BIT_MASK(BTN_GAMEPAD) },
948	},
949	{
950		.flags = INPUT_DEVICE_ID_MATCH_EVBIT |
951				INPUT_DEVICE_ID_MATCH_KEYBIT,
952		.evbit = { BIT_MASK(EV_KEY) },
953		.keybit = { [BIT_WORD(BTN_TRIGGER_HAPPY)] = BIT_MASK(BTN_TRIGGER_HAPPY) },
954	},
955	{ }	/* Terminating entry */
956};
957
958MODULE_DEVICE_TABLE(input, joydev_ids);
959
960static struct input_handler joydev_handler = {
961	.event		= joydev_event,
962	.match		= joydev_match,
963	.connect	= joydev_connect,
964	.disconnect	= joydev_disconnect,
965	.fops		= &joydev_fops,
966	.minor		= JOYDEV_MINOR_BASE,
967	.name		= "joydev",
968	.id_table	= joydev_ids,
969};
970
971static int __init joydev_init(void)
972{
973	return input_register_handler(&joydev_handler);
974}
975
976static void __exit joydev_exit(void)
977{
978	input_unregister_handler(&joydev_handler);
979}
980
981module_init(joydev_init);
982module_exit(joydev_exit);