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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * Event char devices, giving access to raw input device events.
3 *
4 * Copyright (c) 1999-2002 Vojtech Pavlik
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 as published by
8 * the Free Software Foundation.
9 */
10
Joe Perchesda0c4902010-11-29 23:33:07 -080011#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
12
Linus Torvalds1da177e2005-04-16 15:20:36 -070013#define EVDEV_MINOR_BASE 64
14#define EVDEV_MINORS 32
Henrik Rydberg63a64042010-06-10 12:05:24 -070015#define EVDEV_MIN_BUFFER_SIZE 64U
16#define EVDEV_BUF_PACKETS 8
Linus Torvalds1da177e2005-04-16 15:20:36 -070017
18#include <linux/poll.h>
Alexey Dobriyana99bbaf2009-10-04 16:11:37 +040019#include <linux/sched.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070020#include <linux/slab.h>
21#include <linux/module.h>
22#include <linux/init.h>
Henrik Rydberg1cf0c6e2012-02-06 08:49:25 +010023#include <linux/input/mt.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070024#include <linux/major.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070025#include <linux/device.h>
Dmitry Torokhov7f8d4ca2012-10-08 09:07:24 -070026#include <linux/cdev.h>
Philip Langdale2d56f3a2008-10-16 22:31:42 -040027#include "input-compat.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070028
29struct evdev {
Linus Torvalds1da177e2005-04-16 15:20:36 -070030 int open;
Linus Torvalds1da177e2005-04-16 15:20:36 -070031 struct input_handle handle;
32 wait_queue_head_t wait;
Arnd Bergmann2be85272010-03-04 15:50:28 +010033 struct evdev_client __rcu *grab;
Dmitry Torokhovd0ffb9b2007-04-12 01:30:00 -040034 struct list_head client_list;
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -040035 spinlock_t client_lock; /* protects client_list */
36 struct mutex mutex;
Dmitry Torokhov9657d752007-06-14 23:32:24 -040037 struct device dev;
Dmitry Torokhov7f8d4ca2012-10-08 09:07:24 -070038 struct cdev cdev;
Dmitry Torokhov20da92d2010-07-15 23:27:36 -070039 bool exist;
Linus Torvalds1da177e2005-04-16 15:20:36 -070040};
41
Dmitry Torokhovd0ffb9b2007-04-12 01:30:00 -040042struct evdev_client {
Jeff Brown9fb0f142011-04-12 23:29:38 -070043 unsigned int head;
44 unsigned int tail;
Jeff Browncdda9112011-04-26 22:16:11 -070045 unsigned int packet_head; /* [future] position of the first element of next packet */
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -040046 spinlock_t buffer_lock; /* protects access to buffer, head and tail */
Linus Torvalds1da177e2005-04-16 15:20:36 -070047 struct fasync_struct *fasync;
48 struct evdev *evdev;
49 struct list_head node;
John Stultza80b83b2012-02-03 00:19:07 -080050 int clkid;
Jeff Brown9fb0f142011-04-12 23:29:38 -070051 unsigned int bufsize;
Henrik Rydbergb58f7082010-06-23 09:17:56 -070052 struct input_event buffer[];
Linus Torvalds1da177e2005-04-16 15:20:36 -070053};
54
David Herrmann48318022013-04-07 21:13:19 -070055/* flush queued events of type @type, caller must hold client->buffer_lock */
56static void __evdev_flush_queue(struct evdev_client *client, unsigned int type)
57{
58 unsigned int i, head, num;
59 unsigned int mask = client->bufsize - 1;
60 bool is_report;
61 struct input_event *ev;
62
63 BUG_ON(type == EV_SYN);
64
65 head = client->tail;
66 client->packet_head = client->tail;
67
68 /* init to 1 so a leading SYN_REPORT will not be dropped */
69 num = 1;
70
71 for (i = client->tail; i != client->head; i = (i + 1) & mask) {
72 ev = &client->buffer[i];
73 is_report = ev->type == EV_SYN && ev->code == SYN_REPORT;
74
75 if (ev->type == type) {
76 /* drop matched entry */
77 continue;
78 } else if (is_report && !num) {
79 /* drop empty SYN_REPORT groups */
80 continue;
81 } else if (head != i) {
82 /* move entry to fill the gap */
83 client->buffer[head].time = ev->time;
84 client->buffer[head].type = ev->type;
85 client->buffer[head].code = ev->code;
86 client->buffer[head].value = ev->value;
87 }
88
89 num++;
90 head = (head + 1) & mask;
91
92 if (is_report) {
93 num = 0;
94 client->packet_head = head;
95 }
96 }
97
98 client->head = head;
99}
100
101/* queue SYN_DROPPED event */
102static void evdev_queue_syn_dropped(struct evdev_client *client)
103{
104 unsigned long flags;
105 struct input_event ev;
106 ktime_t time;
107
108 time = ktime_get();
109 if (client->clkid != CLOCK_MONOTONIC)
110 time = ktime_sub(time, ktime_get_monotonic_offset());
111
112 ev.time = ktime_to_timeval(time);
113 ev.type = EV_SYN;
114 ev.code = SYN_DROPPED;
115 ev.value = 0;
116
117 spin_lock_irqsave(&client->buffer_lock, flags);
118
119 client->buffer[client->head++] = ev;
120 client->head &= client->bufsize - 1;
121
122 if (unlikely(client->head == client->tail)) {
123 /* drop queue but keep our SYN_DROPPED event */
124 client->tail = (client->head - 1) & (client->bufsize - 1);
125 client->packet_head = client->tail;
126 }
127
128 spin_unlock_irqrestore(&client->buffer_lock, flags);
129}
130
Henrik Rydberga274ac12012-08-29 20:48:02 +0200131static void __pass_event(struct evdev_client *client,
132 const struct input_event *event)
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400133{
Jeff Brown9fb0f142011-04-12 23:29:38 -0700134 client->buffer[client->head++] = *event;
135 client->head &= client->bufsize - 1;
136
137 if (unlikely(client->head == client->tail)) {
138 /*
139 * This effectively "drops" all unconsumed events, leaving
140 * EV_SYN/SYN_DROPPED plus the newest event in the queue.
141 */
142 client->tail = (client->head - 2) & (client->bufsize - 1);
143
144 client->buffer[client->tail].time = event->time;
145 client->buffer[client->tail].type = EV_SYN;
146 client->buffer[client->tail].code = SYN_DROPPED;
147 client->buffer[client->tail].value = 0;
Jeff Browncdda9112011-04-26 22:16:11 -0700148
149 client->packet_head = client->tail;
150 }
151
152 if (event->type == EV_SYN && event->code == SYN_REPORT) {
153 client->packet_head = client->head;
154 kill_fasync(&client->fasync, SIGIO, POLL_IN);
Jeff Brown9fb0f142011-04-12 23:29:38 -0700155 }
Henrik Rydberga274ac12012-08-29 20:48:02 +0200156}
157
158static void evdev_pass_values(struct evdev_client *client,
159 const struct input_value *vals, unsigned int count,
160 ktime_t mono, ktime_t real)
161{
162 struct evdev *evdev = client->evdev;
163 const struct input_value *v;
164 struct input_event event;
165 bool wakeup = false;
166
167 event.time = ktime_to_timeval(client->clkid == CLOCK_MONOTONIC ?
168 mono : real);
169
170 /* Interrupts are disabled, just acquire the lock. */
171 spin_lock(&client->buffer_lock);
172
173 for (v = vals; v != vals + count; v++) {
174 event.type = v->type;
175 event.code = v->code;
176 event.value = v->value;
177 __pass_event(client, &event);
178 if (v->type == EV_SYN && v->code == SYN_REPORT)
179 wakeup = true;
180 }
Jeff Brown9fb0f142011-04-12 23:29:38 -0700181
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400182 spin_unlock(&client->buffer_lock);
Henrik Rydberga274ac12012-08-29 20:48:02 +0200183
184 if (wakeup)
185 wake_up_interruptible(&evdev->wait);
186}
187
188/*
189 * Pass incoming events to all connected clients.
190 */
191static void evdev_events(struct input_handle *handle,
192 const struct input_value *vals, unsigned int count)
193{
194 struct evdev *evdev = handle->private;
195 struct evdev_client *client;
196 ktime_t time_mono, time_real;
197
198 time_mono = ktime_get();
199 time_real = ktime_sub(time_mono, ktime_get_monotonic_offset());
200
201 rcu_read_lock();
202
203 client = rcu_dereference(evdev->grab);
204
205 if (client)
206 evdev_pass_values(client, vals, count, time_mono, time_real);
207 else
208 list_for_each_entry_rcu(client, &evdev->client_list, node)
209 evdev_pass_values(client, vals, count,
210 time_mono, time_real);
211
212 rcu_read_unlock();
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400213}
214
215/*
Dmitry Torokhov82ba56c2007-10-13 15:46:55 -0400216 * Pass incoming event to all connected clients.
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400217 */
218static void evdev_event(struct input_handle *handle,
219 unsigned int type, unsigned int code, int value)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700220{
Henrik Rydberga274ac12012-08-29 20:48:02 +0200221 struct input_value vals[] = { { type, code, value } };
Linus Torvalds1da177e2005-04-16 15:20:36 -0700222
Henrik Rydberga274ac12012-08-29 20:48:02 +0200223 evdev_events(handle, vals, 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700224}
225
226static int evdev_fasync(int fd, struct file *file, int on)
227{
Dmitry Torokhovd0ffb9b2007-04-12 01:30:00 -0400228 struct evdev_client *client = file->private_data;
Dmitry Torokhov1e0afb22006-06-26 01:48:47 -0400229
Jonathan Corbet60aa4922009-02-01 14:52:56 -0700230 return fasync_helper(fd, file, on, &client->fasync);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700231}
232
Dmitry Torokhov1e0afb22006-06-26 01:48:47 -0400233static int evdev_flush(struct file *file, fl_owner_t id)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700234{
Dmitry Torokhovd0ffb9b2007-04-12 01:30:00 -0400235 struct evdev_client *client = file->private_data;
236 struct evdev *evdev = client->evdev;
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400237 int retval;
238
239 retval = mutex_lock_interruptible(&evdev->mutex);
240 if (retval)
241 return retval;
Dmitry Torokhov1e0afb22006-06-26 01:48:47 -0400242
Dmitry Torokhovd0ffb9b2007-04-12 01:30:00 -0400243 if (!evdev->exist)
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400244 retval = -ENODEV;
245 else
246 retval = input_flush_device(&evdev->handle, file);
Dmitry Torokhov1e0afb22006-06-26 01:48:47 -0400247
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400248 mutex_unlock(&evdev->mutex);
249 return retval;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700250}
251
Dmitry Torokhov9657d752007-06-14 23:32:24 -0400252static void evdev_free(struct device *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700253{
Dmitry Torokhov9657d752007-06-14 23:32:24 -0400254 struct evdev *evdev = container_of(dev, struct evdev, dev);
255
Dmitry Torokhova7097ff2008-04-01 00:22:53 -0400256 input_put_device(evdev->handle.dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700257 kfree(evdev);
258}
259
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400260/*
261 * Grabs an event device (along with underlying input device).
262 * This function is called with evdev->mutex taken.
263 */
264static int evdev_grab(struct evdev *evdev, struct evdev_client *client)
265{
266 int error;
267
268 if (evdev->grab)
269 return -EBUSY;
270
271 error = input_grab_device(&evdev->handle);
272 if (error)
273 return error;
274
275 rcu_assign_pointer(evdev->grab, client);
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400276
277 return 0;
278}
279
280static int evdev_ungrab(struct evdev *evdev, struct evdev_client *client)
281{
Dmitry Torokhovdba42582012-05-02 00:13:36 -0700282 struct evdev_client *grab = rcu_dereference_protected(evdev->grab,
283 lockdep_is_held(&evdev->mutex));
284
285 if (grab != client)
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400286 return -EINVAL;
287
288 rcu_assign_pointer(evdev->grab, NULL);
Dmitry Torokhov82ba56c2007-10-13 15:46:55 -0400289 synchronize_rcu();
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400290 input_release_device(&evdev->handle);
291
292 return 0;
293}
294
295static void evdev_attach_client(struct evdev *evdev,
296 struct evdev_client *client)
297{
298 spin_lock(&evdev->client_lock);
299 list_add_tail_rcu(&client->node, &evdev->client_list);
300 spin_unlock(&evdev->client_lock);
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400301}
302
303static void evdev_detach_client(struct evdev *evdev,
304 struct evdev_client *client)
305{
306 spin_lock(&evdev->client_lock);
307 list_del_rcu(&client->node);
308 spin_unlock(&evdev->client_lock);
Dmitry Torokhov82ba56c2007-10-13 15:46:55 -0400309 synchronize_rcu();
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400310}
311
312static int evdev_open_device(struct evdev *evdev)
313{
314 int retval;
315
316 retval = mutex_lock_interruptible(&evdev->mutex);
317 if (retval)
318 return retval;
319
320 if (!evdev->exist)
321 retval = -ENODEV;
Oliver Neukum06445012007-10-12 14:18:40 -0400322 else if (!evdev->open++) {
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400323 retval = input_open_device(&evdev->handle);
Oliver Neukum06445012007-10-12 14:18:40 -0400324 if (retval)
325 evdev->open--;
326 }
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400327
328 mutex_unlock(&evdev->mutex);
329 return retval;
330}
331
332static void evdev_close_device(struct evdev *evdev)
333{
334 mutex_lock(&evdev->mutex);
335
336 if (evdev->exist && !--evdev->open)
337 input_close_device(&evdev->handle);
338
339 mutex_unlock(&evdev->mutex);
340}
341
342/*
343 * Wake up users waiting for IO so they can disconnect from
344 * dead device.
345 */
346static void evdev_hangup(struct evdev *evdev)
347{
348 struct evdev_client *client;
349
350 spin_lock(&evdev->client_lock);
351 list_for_each_entry(client, &evdev->client_list, node)
352 kill_fasync(&client->fasync, SIGIO, POLL_HUP);
353 spin_unlock(&evdev->client_lock);
354
355 wake_up_interruptible(&evdev->wait);
356}
357
Dmitry Torokhovd0ffb9b2007-04-12 01:30:00 -0400358static int evdev_release(struct inode *inode, struct file *file)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700359{
Dmitry Torokhovd0ffb9b2007-04-12 01:30:00 -0400360 struct evdev_client *client = file->private_data;
361 struct evdev *evdev = client->evdev;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700362
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400363 mutex_lock(&evdev->mutex);
Dmitry Torokhovdba42582012-05-02 00:13:36 -0700364 evdev_ungrab(evdev, client);
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400365 mutex_unlock(&evdev->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700366
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400367 evdev_detach_client(evdev, client);
Dmitry Torokhovd0ffb9b2007-04-12 01:30:00 -0400368 kfree(client);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700369
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400370 evdev_close_device(evdev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700371
Linus Torvalds1da177e2005-04-16 15:20:36 -0700372 return 0;
373}
374
Henrik Rydbergb58f7082010-06-23 09:17:56 -0700375static unsigned int evdev_compute_buffer_size(struct input_dev *dev)
376{
Henrik Rydberg63a64042010-06-10 12:05:24 -0700377 unsigned int n_events =
378 max(dev->hint_events_per_packet * EVDEV_BUF_PACKETS,
379 EVDEV_MIN_BUFFER_SIZE);
380
381 return roundup_pow_of_two(n_events);
Henrik Rydbergb58f7082010-06-23 09:17:56 -0700382}
383
Dmitry Torokhovd0ffb9b2007-04-12 01:30:00 -0400384static int evdev_open(struct inode *inode, struct file *file)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700385{
Dmitry Torokhov7f8d4ca2012-10-08 09:07:24 -0700386 struct evdev *evdev = container_of(inode->i_cdev, struct evdev, cdev);
387 unsigned int bufsize = evdev_compute_buffer_size(evdev->handle.dev);
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400388 struct evdev_client *client;
Dmitry Torokhovd542ed82007-04-12 01:30:15 -0400389 int error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700390
Henrik Rydbergb58f7082010-06-23 09:17:56 -0700391 client = kzalloc(sizeof(struct evdev_client) +
392 bufsize * sizeof(struct input_event),
393 GFP_KERNEL);
Dmitry Torokhov7f8d4ca2012-10-08 09:07:24 -0700394 if (!client)
395 return -ENOMEM;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700396
Henrik Rydbergb58f7082010-06-23 09:17:56 -0700397 client->bufsize = bufsize;
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400398 spin_lock_init(&client->buffer_lock);
Dmitry Torokhovd0ffb9b2007-04-12 01:30:00 -0400399 client->evdev = evdev;
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400400 evdev_attach_client(evdev, client);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700401
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400402 error = evdev_open_device(evdev);
403 if (error)
404 goto err_free_client;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700405
Dmitry Torokhovd0ffb9b2007-04-12 01:30:00 -0400406 file->private_data = client;
Dmitry Torokhov3d7bbd42010-02-04 00:30:42 -0800407 nonseekable_open(inode, file);
408
Linus Torvalds1da177e2005-04-16 15:20:36 -0700409 return 0;
Dmitry Torokhov9657d752007-06-14 23:32:24 -0400410
411 err_free_client:
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400412 evdev_detach_client(evdev, client);
Dmitry Torokhov9657d752007-06-14 23:32:24 -0400413 kfree(client);
Dmitry Torokhov9657d752007-06-14 23:32:24 -0400414 return error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700415}
416
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400417static ssize_t evdev_write(struct file *file, const char __user *buffer,
418 size_t count, loff_t *ppos)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700419{
Dmitry Torokhovd0ffb9b2007-04-12 01:30:00 -0400420 struct evdev_client *client = file->private_data;
421 struct evdev *evdev = client->evdev;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700422 struct input_event event;
Heiko Stübner02dfc492012-02-08 23:08:48 -0800423 int retval = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700424
Dmitry Torokhov2872a9b2012-05-02 00:13:37 -0700425 if (count != 0 && count < input_event_size())
Peter Korsgaard439581e2011-02-25 09:30:46 -0800426 return -EINVAL;
427
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400428 retval = mutex_lock_interruptible(&evdev->mutex);
429 if (retval)
430 return retval;
431
432 if (!evdev->exist) {
433 retval = -ENODEV;
434 goto out;
435 }
Juergen Kreileder52658bb2005-05-29 02:26:43 -0500436
Dmitry Torokhov2872a9b2012-05-02 00:13:37 -0700437 while (retval + input_event_size() <= count) {
438
Philip Langdale2d56f3a2008-10-16 22:31:42 -0400439 if (input_event_from_user(buffer + retval, &event)) {
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400440 retval = -EFAULT;
441 goto out;
442 }
Peter Korsgaard439581e2011-02-25 09:30:46 -0800443 retval += input_event_size();
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400444
445 input_inject_event(&evdev->handle,
446 event.type, event.code, event.value);
Dmitry Torokhov2872a9b2012-05-02 00:13:37 -0700447 }
Juergen Kreileder52658bb2005-05-29 02:26:43 -0500448
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400449 out:
450 mutex_unlock(&evdev->mutex);
Juergen Kreileder52658bb2005-05-29 02:26:43 -0500451 return retval;
452}
Juergen Kreileder52658bb2005-05-29 02:26:43 -0500453
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400454static int evdev_fetch_next_event(struct evdev_client *client,
455 struct input_event *event)
456{
457 int have_event;
458
459 spin_lock_irq(&client->buffer_lock);
460
Dima Zavin566cf5b2011-12-30 15:16:44 -0800461 have_event = client->packet_head != client->tail;
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400462 if (have_event) {
463 *event = client->buffer[client->tail++];
Henrik Rydbergb58f7082010-06-23 09:17:56 -0700464 client->tail &= client->bufsize - 1;
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400465 }
466
467 spin_unlock_irq(&client->buffer_lock);
468
469 return have_event;
470}
471
472static ssize_t evdev_read(struct file *file, char __user *buffer,
473 size_t count, loff_t *ppos)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700474{
Dmitry Torokhovd0ffb9b2007-04-12 01:30:00 -0400475 struct evdev_client *client = file->private_data;
476 struct evdev *evdev = client->evdev;
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400477 struct input_event event;
Dmitry Torokhov2872a9b2012-05-02 00:13:37 -0700478 size_t read = 0;
479 int error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700480
Dmitry Torokhov2872a9b2012-05-02 00:13:37 -0700481 if (count != 0 && count < input_event_size())
Linus Torvalds1da177e2005-04-16 15:20:36 -0700482 return -EINVAL;
483
Dmitry Torokhov2872a9b2012-05-02 00:13:37 -0700484 for (;;) {
485 if (!evdev->exist)
486 return -ENODEV;
487
488 if (client->packet_head == client->tail &&
489 (file->f_flags & O_NONBLOCK))
490 return -EAGAIN;
491
492 /*
493 * count == 0 is special - no IO is done but we check
494 * for error conditions (see above).
495 */
496 if (count == 0)
497 break;
498
499 while (read + input_event_size() <= count &&
500 evdev_fetch_next_event(client, &event)) {
501
502 if (input_event_to_user(buffer + read, &event))
503 return -EFAULT;
504
505 read += input_event_size();
506 }
507
508 if (read)
509 break;
510
511 if (!(file->f_flags & O_NONBLOCK)) {
512 error = wait_event_interruptible(evdev->wait,
513 client->packet_head != client->tail ||
514 !evdev->exist);
515 if (error)
516 return error;
517 }
Dima Zavin509f87c2011-12-30 15:16:44 -0800518 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700519
Dmitry Torokhov2872a9b2012-05-02 00:13:37 -0700520 return read;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700521}
522
523/* No kernel lock - fine */
524static unsigned int evdev_poll(struct file *file, poll_table *wait)
525{
Dmitry Torokhovd0ffb9b2007-04-12 01:30:00 -0400526 struct evdev_client *client = file->private_data;
527 struct evdev *evdev = client->evdev;
Dmitry Torokhovc18fb132010-07-15 23:28:42 -0700528 unsigned int mask;
Dmitry Torokhov1e0afb22006-06-26 01:48:47 -0400529
Dmitry Torokhovd0ffb9b2007-04-12 01:30:00 -0400530 poll_wait(file, &evdev->wait, wait);
Dmitry Torokhovc18fb132010-07-15 23:28:42 -0700531
532 mask = evdev->exist ? POLLOUT | POLLWRNORM : POLLHUP | POLLERR;
Jeff Browncdda9112011-04-26 22:16:11 -0700533 if (client->packet_head != client->tail)
Dmitry Torokhovc18fb132010-07-15 23:28:42 -0700534 mask |= POLLIN | POLLRDNORM;
535
536 return mask;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700537}
538
Dmitry Torokhov3a51f7c2005-12-11 12:40:37 -0500539#ifdef CONFIG_COMPAT
540
541#define BITS_PER_LONG_COMPAT (sizeof(compat_long_t) * 8)
Jiri Slaby7b19ada2007-10-18 23:40:32 -0700542#define BITS_TO_LONGS_COMPAT(x) ((((x) - 1) / BITS_PER_LONG_COMPAT) + 1)
Dmitry Torokhov3a51f7c2005-12-11 12:40:37 -0500543
544#ifdef __BIG_ENDIAN
545static int bits_to_user(unsigned long *bits, unsigned int maxbit,
546 unsigned int maxlen, void __user *p, int compat)
547{
548 int len, i;
549
550 if (compat) {
Jiri Slaby7b19ada2007-10-18 23:40:32 -0700551 len = BITS_TO_LONGS_COMPAT(maxbit) * sizeof(compat_long_t);
Kenichi Nagaibf61f8d2007-05-11 01:12:15 -0400552 if (len > maxlen)
Dmitry Torokhov3a51f7c2005-12-11 12:40:37 -0500553 len = maxlen;
554
555 for (i = 0; i < len / sizeof(compat_long_t); i++)
556 if (copy_to_user((compat_long_t __user *) p + i,
557 (compat_long_t *) bits +
558 i + 1 - ((i % 2) << 1),
559 sizeof(compat_long_t)))
560 return -EFAULT;
561 } else {
Jiri Slaby7b19ada2007-10-18 23:40:32 -0700562 len = BITS_TO_LONGS(maxbit) * sizeof(long);
Dmitry Torokhov3a51f7c2005-12-11 12:40:37 -0500563 if (len > maxlen)
564 len = maxlen;
565
566 if (copy_to_user(p, bits, len))
567 return -EFAULT;
568 }
569
570 return len;
571}
572#else
573static int bits_to_user(unsigned long *bits, unsigned int maxbit,
574 unsigned int maxlen, void __user *p, int compat)
575{
576 int len = compat ?
Jiri Slaby7b19ada2007-10-18 23:40:32 -0700577 BITS_TO_LONGS_COMPAT(maxbit) * sizeof(compat_long_t) :
578 BITS_TO_LONGS(maxbit) * sizeof(long);
Dmitry Torokhov3a51f7c2005-12-11 12:40:37 -0500579
580 if (len > maxlen)
581 len = maxlen;
582
583 return copy_to_user(p, bits, len) ? -EFAULT : len;
584}
585#endif /* __BIG_ENDIAN */
586
587#else
588
589static int bits_to_user(unsigned long *bits, unsigned int maxbit,
590 unsigned int maxlen, void __user *p, int compat)
591{
Jiri Slaby7b19ada2007-10-18 23:40:32 -0700592 int len = BITS_TO_LONGS(maxbit) * sizeof(long);
Dmitry Torokhov3a51f7c2005-12-11 12:40:37 -0500593
594 if (len > maxlen)
595 len = maxlen;
596
597 return copy_to_user(p, bits, len) ? -EFAULT : len;
598}
599
600#endif /* CONFIG_COMPAT */
601
602static int str_to_user(const char *str, unsigned int maxlen, void __user *p)
603{
604 int len;
605
606 if (!str)
607 return -ENOENT;
608
609 len = strlen(str) + 1;
610 if (len > maxlen)
611 len = maxlen;
612
613 return copy_to_user(p, str, len) ? -EFAULT : len;
614}
615
Dmitry Torokhovf2afa772008-08-08 11:46:53 -0400616#define OLD_KEY_MAX 0x1ff
Dmitry Torokhov448cd162010-08-02 20:29:10 -0700617static int handle_eviocgbit(struct input_dev *dev,
618 unsigned int type, unsigned int size,
619 void __user *p, int compat_mode)
Linus Torvalds5402a732008-08-05 11:42:42 -0400620{
Dmitry Torokhovf2afa772008-08-08 11:46:53 -0400621 static unsigned long keymax_warn_time;
Linus Torvalds5402a732008-08-05 11:42:42 -0400622 unsigned long *bits;
623 int len;
624
Dmitry Torokhov448cd162010-08-02 20:29:10 -0700625 switch (type) {
Linus Torvalds5402a732008-08-05 11:42:42 -0400626
627 case 0: bits = dev->evbit; len = EV_MAX; break;
628 case EV_KEY: bits = dev->keybit; len = KEY_MAX; break;
629 case EV_REL: bits = dev->relbit; len = REL_MAX; break;
630 case EV_ABS: bits = dev->absbit; len = ABS_MAX; break;
631 case EV_MSC: bits = dev->mscbit; len = MSC_MAX; break;
632 case EV_LED: bits = dev->ledbit; len = LED_MAX; break;
633 case EV_SND: bits = dev->sndbit; len = SND_MAX; break;
634 case EV_FF: bits = dev->ffbit; len = FF_MAX; break;
635 case EV_SW: bits = dev->swbit; len = SW_MAX; break;
636 default: return -EINVAL;
637 }
Dmitry Torokhovf2afa772008-08-08 11:46:53 -0400638
639 /*
640 * Work around bugs in userspace programs that like to do
641 * EVIOCGBIT(EV_KEY, KEY_MAX) and not realize that 'len'
642 * should be in bytes, not in bits.
643 */
Dmitry Torokhov448cd162010-08-02 20:29:10 -0700644 if (type == EV_KEY && size == OLD_KEY_MAX) {
Dmitry Torokhovf2afa772008-08-08 11:46:53 -0400645 len = OLD_KEY_MAX;
646 if (printk_timed_ratelimit(&keymax_warn_time, 10 * 1000))
Joe Perchesda0c4902010-11-29 23:33:07 -0800647 pr_warning("(EVIOCGBIT): Suspicious buffer size %u, "
648 "limiting output to %zu bytes. See "
649 "http://userweb.kernel.org/~dtor/eviocgbit-bug.html\n",
650 OLD_KEY_MAX,
651 BITS_TO_LONGS(OLD_KEY_MAX) * sizeof(long));
Dmitry Torokhovf2afa772008-08-08 11:46:53 -0400652 }
653
Dmitry Torokhov448cd162010-08-02 20:29:10 -0700654 return bits_to_user(bits, len, size, p, compat_mode);
Linus Torvalds5402a732008-08-05 11:42:42 -0400655}
Dmitry Torokhovf2afa772008-08-08 11:46:53 -0400656#undef OLD_KEY_MAX
Linus Torvalds5402a732008-08-05 11:42:42 -0400657
Dmitry Torokhovab4e0192010-12-14 23:53:21 -0800658static int evdev_handle_get_keycode(struct input_dev *dev, void __user *p)
659{
660 struct input_keymap_entry ke = {
661 .len = sizeof(unsigned int),
662 .flags = 0,
663 };
664 int __user *ip = (int __user *)p;
665 int error;
666
667 /* legacy case */
668 if (copy_from_user(ke.scancode, p, sizeof(unsigned int)))
669 return -EFAULT;
670
671 error = input_get_keycode(dev, &ke);
672 if (error)
673 return error;
674
675 if (put_user(ke.keycode, ip + 1))
676 return -EFAULT;
677
678 return 0;
679}
680
681static int evdev_handle_get_keycode_v2(struct input_dev *dev, void __user *p)
Mauro Carvalho Chehab8613e4c2010-09-09 21:54:22 -0700682{
683 struct input_keymap_entry ke;
684 int error;
685
Dmitry Torokhovab4e0192010-12-14 23:53:21 -0800686 if (copy_from_user(&ke, p, sizeof(ke)))
687 return -EFAULT;
Mauro Carvalho Chehab8613e4c2010-09-09 21:54:22 -0700688
Dmitry Torokhovab4e0192010-12-14 23:53:21 -0800689 error = input_get_keycode(dev, &ke);
690 if (error)
691 return error;
Mauro Carvalho Chehab8613e4c2010-09-09 21:54:22 -0700692
Dmitry Torokhovab4e0192010-12-14 23:53:21 -0800693 if (copy_to_user(p, &ke, sizeof(ke)))
694 return -EFAULT;
Mauro Carvalho Chehab8613e4c2010-09-09 21:54:22 -0700695
Mauro Carvalho Chehab8613e4c2010-09-09 21:54:22 -0700696 return 0;
697}
698
Dmitry Torokhovab4e0192010-12-14 23:53:21 -0800699static int evdev_handle_set_keycode(struct input_dev *dev, void __user *p)
700{
701 struct input_keymap_entry ke = {
702 .len = sizeof(unsigned int),
703 .flags = 0,
704 };
705 int __user *ip = (int __user *)p;
706
707 if (copy_from_user(ke.scancode, p, sizeof(unsigned int)))
708 return -EFAULT;
709
710 if (get_user(ke.keycode, ip + 1))
711 return -EFAULT;
712
713 return input_set_keycode(dev, &ke);
714}
715
716static int evdev_handle_set_keycode_v2(struct input_dev *dev, void __user *p)
Mauro Carvalho Chehab8613e4c2010-09-09 21:54:22 -0700717{
718 struct input_keymap_entry ke;
719
Dmitry Torokhovab4e0192010-12-14 23:53:21 -0800720 if (copy_from_user(&ke, p, sizeof(ke)))
721 return -EFAULT;
Mauro Carvalho Chehab8613e4c2010-09-09 21:54:22 -0700722
Dmitry Torokhovab4e0192010-12-14 23:53:21 -0800723 if (ke.len > sizeof(ke.scancode))
724 return -EINVAL;
Mauro Carvalho Chehab8613e4c2010-09-09 21:54:22 -0700725
726 return input_set_keycode(dev, &ke);
727}
728
David Herrmann48318022013-04-07 21:13:19 -0700729/*
730 * If we transfer state to the user, we should flush all pending events
731 * of the same type from the client's queue. Otherwise, they might end up
732 * with duplicate events, which can screw up client's state tracking.
733 * If bits_to_user fails after flushing the queue, we queue a SYN_DROPPED
734 * event so user-space will notice missing events.
735 *
736 * LOCKING:
737 * We need to take event_lock before buffer_lock to avoid dead-locks. But we
738 * need the even_lock only to guarantee consistent state. We can safely release
739 * it while flushing the queue. This allows input-core to handle filters while
740 * we flush the queue.
741 */
742static int evdev_handle_get_val(struct evdev_client *client,
743 struct input_dev *dev, unsigned int type,
744 unsigned long *bits, unsigned int max,
745 unsigned int size, void __user *p, int compat)
746{
747 int ret;
748 unsigned long *mem;
749
750 mem = kmalloc(sizeof(unsigned long) * max, GFP_KERNEL);
751 if (!mem)
752 return -ENOMEM;
753
754 spin_lock_irq(&dev->event_lock);
755 spin_lock(&client->buffer_lock);
756
757 memcpy(mem, bits, sizeof(unsigned long) * max);
758
759 spin_unlock(&dev->event_lock);
760
761 __evdev_flush_queue(client, type);
762
763 spin_unlock_irq(&client->buffer_lock);
764
765 ret = bits_to_user(mem, max, size, p, compat);
766 if (ret < 0)
767 evdev_queue_syn_dropped(client);
768
769 kfree(mem);
770
771 return ret;
772}
773
Henrik Rydberg1cf0c6e2012-02-06 08:49:25 +0100774static int evdev_handle_mt_request(struct input_dev *dev,
775 unsigned int size,
776 int __user *ip)
777{
Henrik Rydberg8d18fba2012-09-15 15:15:58 +0200778 const struct input_mt *mt = dev->mt;
Henrik Rydberg1cf0c6e2012-02-06 08:49:25 +0100779 unsigned int code;
780 int max_slots;
781 int i;
782
783 if (get_user(code, &ip[0]))
784 return -EFAULT;
Henrik Rydberg8d18fba2012-09-15 15:15:58 +0200785 if (!mt || !input_is_mt_value(code))
Henrik Rydberg1cf0c6e2012-02-06 08:49:25 +0100786 return -EINVAL;
787
788 max_slots = (size - sizeof(__u32)) / sizeof(__s32);
Henrik Rydberg8d18fba2012-09-15 15:15:58 +0200789 for (i = 0; i < mt->num_slots && i < max_slots; i++) {
790 int value = input_mt_get_value(&mt->slots[i], code);
791 if (put_user(value, &ip[1 + i]))
Henrik Rydberg1cf0c6e2012-02-06 08:49:25 +0100792 return -EFAULT;
Henrik Rydberg8d18fba2012-09-15 15:15:58 +0200793 }
Henrik Rydberg1cf0c6e2012-02-06 08:49:25 +0100794
795 return 0;
796}
797
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400798static long evdev_do_ioctl(struct file *file, unsigned int cmd,
799 void __user *p, int compat_mode)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700800{
Dmitry Torokhovd0ffb9b2007-04-12 01:30:00 -0400801 struct evdev_client *client = file->private_data;
802 struct evdev *evdev = client->evdev;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700803 struct input_dev *dev = evdev->handle.dev;
804 struct input_absinfo abs;
Anssi Hannula509ca1a2006-07-19 01:40:22 -0400805 struct ff_effect effect;
Dmitry Torokhov3a51f7c2005-12-11 12:40:37 -0500806 int __user *ip = (int __user *)p;
Dmitry Torokhov58b93992010-03-08 22:37:10 -0800807 unsigned int i, t, u, v;
Dmitry Torokhov448cd162010-08-02 20:29:10 -0700808 unsigned int size;
Anssi Hannula509ca1a2006-07-19 01:40:22 -0400809 int error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700810
Dmitry Torokhov448cd162010-08-02 20:29:10 -0700811 /* First we check for fixed-length commands */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700812 switch (cmd) {
813
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400814 case EVIOCGVERSION:
815 return put_user(EV_VERSION, ip);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700816
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400817 case EVIOCGID:
818 if (copy_to_user(p, &dev->id, sizeof(struct input_id)))
819 return -EFAULT;
820 return 0;
Dmitry Torokhov08791e52006-04-29 01:13:21 -0400821
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400822 case EVIOCGREP:
823 if (!test_bit(EV_REP, dev->evbit))
824 return -ENOSYS;
825 if (put_user(dev->rep[REP_DELAY], ip))
826 return -EFAULT;
827 if (put_user(dev->rep[REP_PERIOD], ip + 1))
828 return -EFAULT;
829 return 0;
Dmitry Torokhov08791e52006-04-29 01:13:21 -0400830
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400831 case EVIOCSREP:
832 if (!test_bit(EV_REP, dev->evbit))
833 return -ENOSYS;
834 if (get_user(u, ip))
835 return -EFAULT;
836 if (get_user(v, ip + 1))
837 return -EFAULT;
Dmitry Torokhov08791e52006-04-29 01:13:21 -0400838
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400839 input_inject_event(&evdev->handle, EV_REP, REP_DELAY, u);
840 input_inject_event(&evdev->handle, EV_REP, REP_PERIOD, v);
Dmitry Torokhov3a51f7c2005-12-11 12:40:37 -0500841
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400842 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700843
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400844 case EVIOCRMFF:
845 return input_ff_erase(dev, (int)(unsigned long) p, file);
846
847 case EVIOCGEFFECTS:
848 i = test_bit(EV_FF, dev->evbit) ?
849 dev->ff->max_effects : 0;
850 if (put_user(i, ip))
851 return -EFAULT;
852 return 0;
853
854 case EVIOCGRAB:
855 if (p)
856 return evdev_grab(evdev, client);
857 else
858 return evdev_ungrab(evdev, client);
Dmitry Torokhovab4e0192010-12-14 23:53:21 -0800859
John Stultza80b83b2012-02-03 00:19:07 -0800860 case EVIOCSCLOCKID:
861 if (copy_from_user(&i, p, sizeof(unsigned int)))
862 return -EFAULT;
863 if (i != CLOCK_MONOTONIC && i != CLOCK_REALTIME)
864 return -EINVAL;
865 client->clkid = i;
866 return 0;
867
Dmitry Torokhovab4e0192010-12-14 23:53:21 -0800868 case EVIOCGKEYCODE:
869 return evdev_handle_get_keycode(dev, p);
870
871 case EVIOCSKEYCODE:
872 return evdev_handle_set_keycode(dev, p);
873
874 case EVIOCGKEYCODE_V2:
875 return evdev_handle_get_keycode_v2(dev, p);
876
877 case EVIOCSKEYCODE_V2:
878 return evdev_handle_set_keycode_v2(dev, p);
Dmitry Torokhov448cd162010-08-02 20:29:10 -0700879 }
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400880
Dmitry Torokhov448cd162010-08-02 20:29:10 -0700881 size = _IOC_SIZE(cmd);
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400882
Dmitry Torokhov448cd162010-08-02 20:29:10 -0700883 /* Now check variable-length commands */
884#define EVIOC_MASK_SIZE(nr) ((nr) & ~(_IOC_SIZEMASK << _IOC_SIZESHIFT))
Dmitry Torokhov448cd162010-08-02 20:29:10 -0700885 switch (EVIOC_MASK_SIZE(cmd)) {
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400886
Henrik Rydberg85b77202010-12-18 20:51:13 +0100887 case EVIOCGPROP(0):
888 return bits_to_user(dev->propbit, INPUT_PROP_MAX,
889 size, p, compat_mode);
890
Henrik Rydberg1cf0c6e2012-02-06 08:49:25 +0100891 case EVIOCGMTSLOTS(0):
892 return evdev_handle_mt_request(dev, size, ip);
893
Dmitry Torokhov448cd162010-08-02 20:29:10 -0700894 case EVIOCGKEY(0):
David Herrmann48318022013-04-07 21:13:19 -0700895 return evdev_handle_get_val(client, dev, EV_KEY, dev->key,
896 KEY_MAX, size, p, compat_mode);
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400897
Dmitry Torokhov448cd162010-08-02 20:29:10 -0700898 case EVIOCGLED(0):
David Herrmann48318022013-04-07 21:13:19 -0700899 return evdev_handle_get_val(client, dev, EV_LED, dev->led,
900 LED_MAX, size, p, compat_mode);
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400901
Dmitry Torokhov448cd162010-08-02 20:29:10 -0700902 case EVIOCGSND(0):
David Herrmann48318022013-04-07 21:13:19 -0700903 return evdev_handle_get_val(client, dev, EV_SND, dev->snd,
904 SND_MAX, size, p, compat_mode);
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400905
Dmitry Torokhov448cd162010-08-02 20:29:10 -0700906 case EVIOCGSW(0):
David Herrmann48318022013-04-07 21:13:19 -0700907 return evdev_handle_get_val(client, dev, EV_SW, dev->sw,
908 SW_MAX, size, p, compat_mode);
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400909
Dmitry Torokhov448cd162010-08-02 20:29:10 -0700910 case EVIOCGNAME(0):
911 return str_to_user(dev->name, size, p);
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400912
Dmitry Torokhov448cd162010-08-02 20:29:10 -0700913 case EVIOCGPHYS(0):
914 return str_to_user(dev->phys, size, p);
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400915
Dmitry Torokhov448cd162010-08-02 20:29:10 -0700916 case EVIOCGUNIQ(0):
917 return str_to_user(dev->uniq, size, p);
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400918
Dmitry Torokhov448cd162010-08-02 20:29:10 -0700919 case EVIOC_MASK_SIZE(EVIOCSFF):
920 if (input_ff_effect_from_user(p, size, &effect))
921 return -EFAULT;
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400922
Dmitry Torokhov448cd162010-08-02 20:29:10 -0700923 error = input_ff_upload(dev, &effect, file);
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400924
Dmitry Torokhov448cd162010-08-02 20:29:10 -0700925 if (put_user(effect.id, &(((struct ff_effect __user *)p)->id)))
926 return -EFAULT;
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400927
Dmitry Torokhov448cd162010-08-02 20:29:10 -0700928 return error;
929 }
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400930
Dmitry Torokhov448cd162010-08-02 20:29:10 -0700931 /* Multi-number variable-length handlers */
932 if (_IOC_TYPE(cmd) != 'E')
933 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700934
Dmitry Torokhov448cd162010-08-02 20:29:10 -0700935 if (_IOC_DIR(cmd) == _IOC_READ) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700936
Dmitry Torokhov448cd162010-08-02 20:29:10 -0700937 if ((_IOC_NR(cmd) & ~EV_MAX) == _IOC_NR(EVIOCGBIT(0, 0)))
938 return handle_eviocgbit(dev,
939 _IOC_NR(cmd) & EV_MAX, size,
940 p, compat_mode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700941
Dmitry Torokhov448cd162010-08-02 20:29:10 -0700942 if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCGABS(0))) {
Adam Dawidowskif2278f32008-06-02 01:08:10 -0400943
Daniel Mack0a74a1d2010-10-18 08:43:30 -0700944 if (!dev->absinfo)
945 return -EINVAL;
946
Dmitry Torokhov448cd162010-08-02 20:29:10 -0700947 t = _IOC_NR(cmd) & ABS_MAX;
948 abs = dev->absinfo[t];
Adam Dawidowskif2278f32008-06-02 01:08:10 -0400949
Dmitry Torokhov448cd162010-08-02 20:29:10 -0700950 if (copy_to_user(p, &abs, min_t(size_t,
951 size, sizeof(struct input_absinfo))))
952 return -EFAULT;
Adam Dawidowskif2278f32008-06-02 01:08:10 -0400953
Dmitry Torokhov448cd162010-08-02 20:29:10 -0700954 return 0;
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400955 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700956 }
Dmitry Torokhov448cd162010-08-02 20:29:10 -0700957
Daniel Mackf9ce6eb2010-10-18 08:43:50 -0700958 if (_IOC_DIR(cmd) == _IOC_WRITE) {
Dmitry Torokhov448cd162010-08-02 20:29:10 -0700959
960 if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCSABS(0))) {
961
Daniel Mack0a74a1d2010-10-18 08:43:30 -0700962 if (!dev->absinfo)
963 return -EINVAL;
964
Dmitry Torokhov448cd162010-08-02 20:29:10 -0700965 t = _IOC_NR(cmd) & ABS_MAX;
966
967 if (copy_from_user(&abs, p, min_t(size_t,
968 size, sizeof(struct input_absinfo))))
969 return -EFAULT;
970
971 if (size < sizeof(struct input_absinfo))
972 abs.resolution = 0;
973
974 /* We can't change number of reserved MT slots */
975 if (t == ABS_MT_SLOT)
976 return -EINVAL;
977
978 /*
979 * Take event lock to ensure that we are not
980 * changing device parameters in the middle
981 * of event.
982 */
983 spin_lock_irq(&dev->event_lock);
984 dev->absinfo[t] = abs;
985 spin_unlock_irq(&dev->event_lock);
986
987 return 0;
988 }
989 }
990
Linus Torvalds1da177e2005-04-16 15:20:36 -0700991 return -EINVAL;
992}
993
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -0400994static long evdev_ioctl_handler(struct file *file, unsigned int cmd,
995 void __user *p, int compat_mode)
996{
997 struct evdev_client *client = file->private_data;
998 struct evdev *evdev = client->evdev;
999 int retval;
1000
1001 retval = mutex_lock_interruptible(&evdev->mutex);
1002 if (retval)
1003 return retval;
1004
1005 if (!evdev->exist) {
1006 retval = -ENODEV;
1007 goto out;
1008 }
1009
1010 retval = evdev_do_ioctl(file, cmd, p, compat_mode);
1011
1012 out:
1013 mutex_unlock(&evdev->mutex);
1014 return retval;
1015}
1016
Dmitry Torokhov3a51f7c2005-12-11 12:40:37 -05001017static long evdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1018{
1019 return evdev_ioctl_handler(file, cmd, (void __user *)arg, 0);
1020}
1021
Juergen Kreileder52658bb2005-05-29 02:26:43 -05001022#ifdef CONFIG_COMPAT
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -04001023static long evdev_ioctl_compat(struct file *file,
1024 unsigned int cmd, unsigned long arg)
Juergen Kreileder52658bb2005-05-29 02:26:43 -05001025{
Dmitry Torokhov3a51f7c2005-12-11 12:40:37 -05001026 return evdev_ioctl_handler(file, cmd, compat_ptr(arg), 1);
Juergen Kreileder52658bb2005-05-29 02:26:43 -05001027}
1028#endif
1029
Dmitry Torokhov66e66112006-09-14 01:31:59 -04001030static const struct file_operations evdev_fops = {
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -04001031 .owner = THIS_MODULE,
1032 .read = evdev_read,
1033 .write = evdev_write,
1034 .poll = evdev_poll,
1035 .open = evdev_open,
1036 .release = evdev_release,
1037 .unlocked_ioctl = evdev_ioctl,
Juergen Kreileder52658bb2005-05-29 02:26:43 -05001038#ifdef CONFIG_COMPAT
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -04001039 .compat_ioctl = evdev_ioctl_compat,
Juergen Kreileder52658bb2005-05-29 02:26:43 -05001040#endif
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -04001041 .fasync = evdev_fasync,
Arnd Bergmann6038f372010-08-15 18:52:59 +02001042 .flush = evdev_flush,
1043 .llseek = no_llseek,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001044};
1045
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -04001046/*
1047 * Mark device non-existent. This disables writes, ioctls and
1048 * prevents new users from opening the device. Already posted
1049 * blocking reads will stay, however new ones will fail.
1050 */
1051static void evdev_mark_dead(struct evdev *evdev)
1052{
1053 mutex_lock(&evdev->mutex);
Dmitry Torokhov20da92d2010-07-15 23:27:36 -07001054 evdev->exist = false;
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -04001055 mutex_unlock(&evdev->mutex);
1056}
1057
1058static void evdev_cleanup(struct evdev *evdev)
1059{
1060 struct input_handle *handle = &evdev->handle;
1061
1062 evdev_mark_dead(evdev);
1063 evdev_hangup(evdev);
Dmitry Torokhov7f8d4ca2012-10-08 09:07:24 -07001064
1065 cdev_del(&evdev->cdev);
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -04001066
1067 /* evdev is marked dead so no one else accesses evdev->open */
1068 if (evdev->open) {
1069 input_flush_device(handle, NULL);
1070 input_close_device(handle);
1071 }
1072}
1073
1074/*
1075 * Create new evdev device. Note that input core serializes calls
Dmitry Torokhov7f8d4ca2012-10-08 09:07:24 -07001076 * to connect and disconnect.
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -04001077 */
Dmitry Torokhov5b2a08262007-04-12 01:29:46 -04001078static int evdev_connect(struct input_handler *handler, struct input_dev *dev,
1079 const struct input_device_id *id)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001080{
1081 struct evdev *evdev;
1082 int minor;
Dmitry Torokhov7f8d4ca2012-10-08 09:07:24 -07001083 int dev_no;
Dmitry Torokhov5b2a08262007-04-12 01:29:46 -04001084 int error;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001085
Dmitry Torokhov7f8d4ca2012-10-08 09:07:24 -07001086 minor = input_get_new_minor(EVDEV_MINOR_BASE, EVDEV_MINORS, true);
1087 if (minor < 0) {
1088 error = minor;
1089 pr_err("failed to reserve new minor: %d\n", error);
1090 return error;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001091 }
1092
Dmitry Torokhov5b2a08262007-04-12 01:29:46 -04001093 evdev = kzalloc(sizeof(struct evdev), GFP_KERNEL);
Dmitry Torokhov7f8d4ca2012-10-08 09:07:24 -07001094 if (!evdev) {
1095 error = -ENOMEM;
1096 goto err_free_minor;
1097 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001098
Dmitry Torokhovd0ffb9b2007-04-12 01:30:00 -04001099 INIT_LIST_HEAD(&evdev->client_list);
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -04001100 spin_lock_init(&evdev->client_lock);
1101 mutex_init(&evdev->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001102 init_waitqueue_head(&evdev->wait);
Dmitry Torokhov20da92d2010-07-15 23:27:36 -07001103 evdev->exist = true;
Dmitry Torokhov7f8d4ca2012-10-08 09:07:24 -07001104
1105 dev_no = minor;
1106 /* Normalize device number if it falls into legacy range */
1107 if (dev_no < EVDEV_MINOR_BASE + EVDEV_MINORS)
1108 dev_no -= EVDEV_MINOR_BASE;
1109 dev_set_name(&evdev->dev, "event%d", dev_no);
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -04001110
Dmitry Torokhova7097ff2008-04-01 00:22:53 -04001111 evdev->handle.dev = input_get_device(dev);
Thadeu Lima de Souza Cascardo3d5cb602009-05-09 16:08:04 -07001112 evdev->handle.name = dev_name(&evdev->dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001113 evdev->handle.handler = handler;
1114 evdev->handle.private = evdev;
Dmitry Torokhov9657d752007-06-14 23:32:24 -04001115
Dmitry Torokhov7f8d4ca2012-10-08 09:07:24 -07001116 evdev->dev.devt = MKDEV(INPUT_MAJOR, minor);
Dmitry Torokhov9657d752007-06-14 23:32:24 -04001117 evdev->dev.class = &input_class;
1118 evdev->dev.parent = &dev->dev;
Dmitry Torokhov9657d752007-06-14 23:32:24 -04001119 evdev->dev.release = evdev_free;
1120 device_initialize(&evdev->dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001121
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -04001122 error = input_register_handle(&evdev->handle);
Dmitry Torokhov5b2a08262007-04-12 01:29:46 -04001123 if (error)
Dmitry Torokhov9657d752007-06-14 23:32:24 -04001124 goto err_free_evdev;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001125
Dmitry Torokhov7f8d4ca2012-10-08 09:07:24 -07001126 cdev_init(&evdev->cdev, &evdev_fops);
Dmitry Torokhov4a215aa2012-10-21 17:57:20 -07001127 evdev->cdev.kobj.parent = &evdev->dev.kobj;
Dmitry Torokhov7f8d4ca2012-10-08 09:07:24 -07001128 error = cdev_add(&evdev->cdev, evdev->dev.devt, 1);
Dmitry Torokhov5b2a08262007-04-12 01:29:46 -04001129 if (error)
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -04001130 goto err_unregister_handle;
1131
1132 error = device_add(&evdev->dev);
1133 if (error)
1134 goto err_cleanup_evdev;
Dmitry Torokhov5b2a08262007-04-12 01:29:46 -04001135
1136 return 0;
1137
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -04001138 err_cleanup_evdev:
1139 evdev_cleanup(evdev);
1140 err_unregister_handle:
1141 input_unregister_handle(&evdev->handle);
Dmitry Torokhov5b2a08262007-04-12 01:29:46 -04001142 err_free_evdev:
Dmitry Torokhov9657d752007-06-14 23:32:24 -04001143 put_device(&evdev->dev);
Dmitry Torokhov7f8d4ca2012-10-08 09:07:24 -07001144 err_free_minor:
1145 input_free_minor(minor);
Dmitry Torokhov5b2a08262007-04-12 01:29:46 -04001146 return error;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001147}
1148
1149static void evdev_disconnect(struct input_handle *handle)
1150{
1151 struct evdev *evdev = handle->private;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001152
Dmitry Torokhov9657d752007-06-14 23:32:24 -04001153 device_del(&evdev->dev);
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -04001154 evdev_cleanup(evdev);
Dmitry Torokhov7f8d4ca2012-10-08 09:07:24 -07001155 input_free_minor(MINOR(evdev->dev.devt));
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -04001156 input_unregister_handle(handle);
Dmitry Torokhov9657d752007-06-14 23:32:24 -04001157 put_device(&evdev->dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001158}
1159
Dmitry Torokhov66e66112006-09-14 01:31:59 -04001160static const struct input_device_id evdev_ids[] = {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001161 { .driver_info = 1 }, /* Matches all devices */
1162 { }, /* Terminating zero entry */
1163};
1164
1165MODULE_DEVICE_TABLE(input, evdev_ids);
1166
1167static struct input_handler evdev_handler = {
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -04001168 .event = evdev_event,
Henrik Rydberga274ac12012-08-29 20:48:02 +02001169 .events = evdev_events,
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -04001170 .connect = evdev_connect,
1171 .disconnect = evdev_disconnect,
Dmitry Torokhov7f8d4ca2012-10-08 09:07:24 -07001172 .legacy_minors = true,
Dmitry Torokhov6addb1d2007-08-30 00:22:18 -04001173 .minor = EVDEV_MINOR_BASE,
1174 .name = "evdev",
1175 .id_table = evdev_ids,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001176};
1177
1178static int __init evdev_init(void)
1179{
Dmitry Torokhov4263cf02006-09-14 01:32:39 -04001180 return input_register_handler(&evdev_handler);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001181}
1182
1183static void __exit evdev_exit(void)
1184{
1185 input_unregister_handler(&evdev_handler);
1186}
1187
1188module_init(evdev_init);
1189module_exit(evdev_exit);
1190
1191MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
1192MODULE_DESCRIPTION("Input driver event char devices");
1193MODULE_LICENSE("GPL");