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Merge tag 'block-5.11-2021-01-10' of git://git.kernel.dk/linux-block
[linux/fpc-iii.git] / drivers / hid / hidraw.c
blob79faac87a06ff8ab4acb56021a0a6388cf2ee261
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * HID raw devices, giving access to raw HID events.
4 *
5 * In comparison to hiddev, this device does not process the
6 * hid events at all (no parsing, no lookups). This lets applications
7 * to work on raw hid events as they want to, and avoids a need to
8 * use a transport-specific userspace libhid/libusb libraries.
9 *
10 * Copyright (c) 2007-2014 Jiri Kosina
11 */
12
13
14 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
15
16 #include <linux/fs.h>
17 #include <linux/module.h>
18 #include <linux/errno.h>
19 #include <linux/kernel.h>
20 #include <linux/init.h>
21 #include <linux/cdev.h>
22 #include <linux/poll.h>
23 #include <linux/device.h>
24 #include <linux/major.h>
25 #include <linux/slab.h>
26 #include <linux/hid.h>
27 #include <linux/mutex.h>
28 #include <linux/sched/signal.h>
29 #include <linux/string.h>
30
31 #include <linux/hidraw.h>
32
33 static int hidraw_major;
34 static struct cdev hidraw_cdev;
35 static struct class *hidraw_class;
36 static struct hidraw *hidraw_table[HIDRAW_MAX_DEVICES];
37 static DEFINE_MUTEX(minors_lock);
38
39 static ssize_t hidraw_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos)
40 {
41 struct hidraw_list *list = file->private_data;
42 int ret = 0, len;
43 DECLARE_WAITQUEUE(wait, current);
44
45 mutex_lock(&list->read_mutex);
46
47 while (ret == 0) {
48 if (list->head == list->tail) {
49 add_wait_queue(&list->hidraw->wait, &wait);
50 set_current_state(TASK_INTERRUPTIBLE);
51
52 while (list->head == list->tail) {
53 if (signal_pending(current)) {
54 ret = -ERESTARTSYS;
55 break;
56 }
57 if (!list->hidraw->exist) {
58 ret = -EIO;
59 break;
60 }
61 if (file->f_flags & O_NONBLOCK) {
62 ret = -EAGAIN;
63 break;
64 }
65
66 /* allow O_NONBLOCK to work well from other threads */
67 mutex_unlock(&list->read_mutex);
68 schedule();
69 mutex_lock(&list->read_mutex);
70 set_current_state(TASK_INTERRUPTIBLE);
71 }
72
73 set_current_state(TASK_RUNNING);
74 remove_wait_queue(&list->hidraw->wait, &wait);
75 }
76
77 if (ret)
78 goto out;
79
80 len = list->buffer[list->tail].len > count ?
81 count : list->buffer[list->tail].len;
82
83 if (list->buffer[list->tail].value) {
84 if (copy_to_user(buffer, list->buffer[list->tail].value, len)) {
85 ret = -EFAULT;
86 goto out;
87 }
88 ret = len;
89 }
90
91 kfree(list->buffer[list->tail].value);
92 list->buffer[list->tail].value = NULL;
93 list->tail = (list->tail + 1) & (HIDRAW_BUFFER_SIZE - 1);
94 }
95 out:
96 mutex_unlock(&list->read_mutex);
97 return ret;
98 }
99
100 /*
101 * The first byte of the report buffer is expected to be a report number.
102 */
103 static ssize_t hidraw_send_report(struct file *file, const char __user *buffer, size_t count, unsigned char report_type)
104 {
105 unsigned int minor = iminor(file_inode(file));
106 struct hid_device *dev;
107 __u8 *buf;
108 int ret = 0;
109
110 lockdep_assert_held(&minors_lock);
111
112 if (!hidraw_table[minor] || !hidraw_table[minor]->exist) {
113 ret = -ENODEV;
114 goto out;
115 }
116
117 dev = hidraw_table[minor]->hid;
118
119 if (count > HID_MAX_BUFFER_SIZE) {
120 hid_warn(dev, "pid %d passed too large report\n",
121 task_pid_nr(current));
122 ret = -EINVAL;
123 goto out;
124 }
125
126 if (count < 2) {
127 hid_warn(dev, "pid %d passed too short report\n",
128 task_pid_nr(current));
129 ret = -EINVAL;
130 goto out;
131 }
132
133 buf = memdup_user(buffer, count);
134 if (IS_ERR(buf)) {
135 ret = PTR_ERR(buf);
136 goto out;
137 }
138
139 if ((report_type == HID_OUTPUT_REPORT) &&
140 !(dev->quirks & HID_QUIRK_NO_OUTPUT_REPORTS_ON_INTR_EP)) {
141 ret = hid_hw_output_report(dev, buf, count);
142 /*
143 * compatibility with old implementation of USB-HID and I2C-HID:
144 * if the device does not support receiving output reports,
145 * on an interrupt endpoint, fallback to SET_REPORT HID command.
146 */
147 if (ret != -ENOSYS)
148 goto out_free;
149 }
150
151 ret = hid_hw_raw_request(dev, buf[0], buf, count, report_type,
152 HID_REQ_SET_REPORT);
153
154 out_free:
155 kfree(buf);
156 out:
157 return ret;
158 }
159
160 static ssize_t hidraw_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
161 {
162 ssize_t ret;
163 mutex_lock(&minors_lock);
164 ret = hidraw_send_report(file, buffer, count, HID_OUTPUT_REPORT);
165 mutex_unlock(&minors_lock);
166 return ret;
167 }
168
169
170 /*
171 * This function performs a Get_Report transfer over the control endpoint
172 * per section 7.2.1 of the HID specification, version 1.1. The first byte
173 * of buffer is the report number to request, or 0x0 if the device does not
174 * use numbered reports. The report_type parameter can be HID_FEATURE_REPORT
175 * or HID_INPUT_REPORT.
176 */
177 static ssize_t hidraw_get_report(struct file *file, char __user *buffer, size_t count, unsigned char report_type)
178 {
179 unsigned int minor = iminor(file_inode(file));
180 struct hid_device *dev;
181 __u8 *buf;
182 int ret = 0, len;
183 unsigned char report_number;
184
185 lockdep_assert_held(&minors_lock);
186
187 if (!hidraw_table[minor] || !hidraw_table[minor]->exist) {
188 ret = -ENODEV;
189 goto out;
190 }
191
192 dev = hidraw_table[minor]->hid;
193
194 if (!dev->ll_driver->raw_request) {
195 ret = -ENODEV;
196 goto out;
197 }
198
199 if (count > HID_MAX_BUFFER_SIZE) {
200 hid_warn(dev, "pid %d passed too large report\n",
201 task_pid_nr(current));
202 ret = -EINVAL;
203 goto out;
204 }
205
206 if (count < 2) {
207 hid_warn(dev, "pid %d passed too short report\n",
208 task_pid_nr(current));
209 ret = -EINVAL;
210 goto out;
211 }
212
213 buf = kmalloc(count, GFP_KERNEL);
214 if (!buf) {
215 ret = -ENOMEM;
216 goto out;
217 }
218
219 /*
220 * Read the first byte from the user. This is the report number,
221 * which is passed to hid_hw_raw_request().
222 */
223 if (copy_from_user(&report_number, buffer, 1)) {
224 ret = -EFAULT;
225 goto out_free;
226 }
227
228 ret = hid_hw_raw_request(dev, report_number, buf, count, report_type,
229 HID_REQ_GET_REPORT);
230
231 if (ret < 0)
232 goto out_free;
233
234 len = (ret < count) ? ret : count;
235
236 if (copy_to_user(buffer, buf, len)) {
237 ret = -EFAULT;
238 goto out_free;
239 }
240
241 ret = len;
242
243 out_free:
244 kfree(buf);
245 out:
246 return ret;
247 }
248
249 static __poll_t hidraw_poll(struct file *file, poll_table *wait)
250 {
251 struct hidraw_list *list = file->private_data;
252 __poll_t mask = EPOLLOUT | EPOLLWRNORM; /* hidraw is always writable */
253
254 poll_wait(file, &list->hidraw->wait, wait);
255 if (list->head != list->tail)
256 mask |= EPOLLIN | EPOLLRDNORM;
257 if (!list->hidraw->exist)
258 mask |= EPOLLERR | EPOLLHUP;
259 return mask;
260 }
261
262 static int hidraw_open(struct inode *inode, struct file *file)
263 {
264 unsigned int minor = iminor(inode);
265 struct hidraw *dev;
266 struct hidraw_list *list;
267 unsigned long flags;
268 int err = 0;
269
270 if (!(list = kzalloc(sizeof(struct hidraw_list), GFP_KERNEL))) {
271 err = -ENOMEM;
272 goto out;
273 }
274
275 mutex_lock(&minors_lock);
276 if (!hidraw_table[minor] || !hidraw_table[minor]->exist) {
277 err = -ENODEV;
278 goto out_unlock;
279 }
280
281 dev = hidraw_table[minor];
282 if (!dev->open++) {
283 err = hid_hw_power(dev->hid, PM_HINT_FULLON);
284 if (err < 0) {
285 dev->open--;
286 goto out_unlock;
287 }
288
289 err = hid_hw_open(dev->hid);
290 if (err < 0) {
291 hid_hw_power(dev->hid, PM_HINT_NORMAL);
292 dev->open--;
293 goto out_unlock;
294 }
295 }
296
297 list->hidraw = hidraw_table[minor];
298 mutex_init(&list->read_mutex);
299 spin_lock_irqsave(&hidraw_table[minor]->list_lock, flags);
300 list_add_tail(&list->node, &hidraw_table[minor]->list);
301 spin_unlock_irqrestore(&hidraw_table[minor]->list_lock, flags);
302 file->private_data = list;
303 out_unlock:
304 mutex_unlock(&minors_lock);
305 out:
306 if (err < 0)
307 kfree(list);
308 return err;
309
310 }
311
312 static int hidraw_fasync(int fd, struct file *file, int on)
313 {
314 struct hidraw_list *list = file->private_data;
315
316 return fasync_helper(fd, file, on, &list->fasync);
317 }
318
319 static void drop_ref(struct hidraw *hidraw, int exists_bit)
320 {
321 if (exists_bit) {
322 hidraw->exist = 0;
323 if (hidraw->open) {
324 hid_hw_close(hidraw->hid);
325 wake_up_interruptible(&hidraw->wait);
326 }
327 device_destroy(hidraw_class,
328 MKDEV(hidraw_major, hidraw->minor));
329 } else {
330 --hidraw->open;
331 }
332 if (!hidraw->open) {
333 if (!hidraw->exist) {
334 hidraw_table[hidraw->minor] = NULL;
335 kfree(hidraw);
336 } else {
337 /* close device for last reader */
338 hid_hw_close(hidraw->hid);
339 hid_hw_power(hidraw->hid, PM_HINT_NORMAL);
340 }
341 }
342 }
343
344 static int hidraw_release(struct inode * inode, struct file * file)
345 {
346 unsigned int minor = iminor(inode);
347 struct hidraw_list *list = file->private_data;
348 unsigned long flags;
349
350 mutex_lock(&minors_lock);
351
352 spin_lock_irqsave(&hidraw_table[minor]->list_lock, flags);
353 list_del(&list->node);
354 spin_unlock_irqrestore(&hidraw_table[minor]->list_lock, flags);
355 kfree(list);
356
357 drop_ref(hidraw_table[minor], 0);
358
359 mutex_unlock(&minors_lock);
360 return 0;
361 }
362
363 static long hidraw_ioctl(struct file *file, unsigned int cmd,
364 unsigned long arg)
365 {
366 struct inode *inode = file_inode(file);
367 unsigned int minor = iminor(inode);
368 long ret = 0;
369 struct hidraw *dev;
370 void __user *user_arg = (void __user*) arg;
371
372 mutex_lock(&minors_lock);
373 dev = hidraw_table[minor];
374 if (!dev || !dev->exist) {
375 ret = -ENODEV;
376 goto out;
377 }
378
379 switch (cmd) {
380 case HIDIOCGRDESCSIZE:
381 if (put_user(dev->hid->rsize, (int __user *)arg))
382 ret = -EFAULT;
383 break;
384
385 case HIDIOCGRDESC:
386 {
387 __u32 len;
388
389 if (get_user(len, (int __user *)arg))
390 ret = -EFAULT;
391 else if (len > HID_MAX_DESCRIPTOR_SIZE - 1)
392 ret = -EINVAL;
393 else if (copy_to_user(user_arg + offsetof(
394 struct hidraw_report_descriptor,
395 value[0]),
396 dev->hid->rdesc,
397 min(dev->hid->rsize, len)))
398 ret = -EFAULT;
399 break;
400 }
401 case HIDIOCGRAWINFO:
402 {
403 struct hidraw_devinfo dinfo;
404
405 dinfo.bustype = dev->hid->bus;
406 dinfo.vendor = dev->hid->vendor;
407 dinfo.product = dev->hid->product;
408 if (copy_to_user(user_arg, &dinfo, sizeof(dinfo)))
409 ret = -EFAULT;
410 break;
411 }
412 default:
413 {
414 struct hid_device *hid = dev->hid;
415 if (_IOC_TYPE(cmd) != 'H') {
416 ret = -EINVAL;
417 break;
418 }
419
420 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCSFEATURE(0))) {
421 int len = _IOC_SIZE(cmd);
422 ret = hidraw_send_report(file, user_arg, len, HID_FEATURE_REPORT);
423 break;
424 }
425 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGFEATURE(0))) {
426 int len = _IOC_SIZE(cmd);
427 ret = hidraw_get_report(file, user_arg, len, HID_FEATURE_REPORT);
428 break;
429 }
430
431 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCSINPUT(0))) {
432 int len = _IOC_SIZE(cmd);
433 ret = hidraw_send_report(file, user_arg, len, HID_INPUT_REPORT);
434 break;
435 }
436 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGINPUT(0))) {
437 int len = _IOC_SIZE(cmd);
438 ret = hidraw_get_report(file, user_arg, len, HID_INPUT_REPORT);
439 break;
440 }
441
442 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCSOUTPUT(0))) {
443 int len = _IOC_SIZE(cmd);
444 ret = hidraw_send_report(file, user_arg, len, HID_OUTPUT_REPORT);
445 break;
446 }
447 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGOUTPUT(0))) {
448 int len = _IOC_SIZE(cmd);
449 ret = hidraw_get_report(file, user_arg, len, HID_OUTPUT_REPORT);
450 break;
451 }
452
453 /* Begin Read-only ioctls. */
454 if (_IOC_DIR(cmd) != _IOC_READ) {
455 ret = -EINVAL;
456 break;
457 }
458
459 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGRAWNAME(0))) {
460 int len = strlen(hid->name) + 1;
461 if (len > _IOC_SIZE(cmd))
462 len = _IOC_SIZE(cmd);
463 ret = copy_to_user(user_arg, hid->name, len) ?
464 -EFAULT : len;
465 break;
466 }
467
468 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGRAWPHYS(0))) {
469 int len = strlen(hid->phys) + 1;
470 if (len > _IOC_SIZE(cmd))
471 len = _IOC_SIZE(cmd);
472 ret = copy_to_user(user_arg, hid->phys, len) ?
473 -EFAULT : len;
474 break;
475 }
476
477 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGRAWUNIQ(0))) {
478 int len = strlen(hid->uniq) + 1;
479 if (len > _IOC_SIZE(cmd))
480 len = _IOC_SIZE(cmd);
481 ret = copy_to_user(user_arg, hid->uniq, len) ?
482 -EFAULT : len;
483 break;
484 }
485 }
486
487 ret = -ENOTTY;
488 }
489 out:
490 mutex_unlock(&minors_lock);
491 return ret;
492 }
493
494 static const struct file_operations hidraw_ops = {
495 .owner = THIS_MODULE,
496 .read = hidraw_read,
497 .write = hidraw_write,
498 .poll = hidraw_poll,
499 .open = hidraw_open,
500 .release = hidraw_release,
501 .unlocked_ioctl = hidraw_ioctl,
502 .fasync = hidraw_fasync,
503 .compat_ioctl = compat_ptr_ioctl,
504 .llseek = noop_llseek,
505 };
506
507 int hidraw_report_event(struct hid_device *hid, u8 *data, int len)
508 {
509 struct hidraw *dev = hid->hidraw;
510 struct hidraw_list *list;
511 int ret = 0;
512 unsigned long flags;
513
514 spin_lock_irqsave(&dev->list_lock, flags);
515 list_for_each_entry(list, &dev->list, node) {
516 int new_head = (list->head + 1) & (HIDRAW_BUFFER_SIZE - 1);
517
518 if (new_head == list->tail)
519 continue;
520
521 if (!(list->buffer[list->head].value = kmemdup(data, len, GFP_ATOMIC))) {
522 ret = -ENOMEM;
523 break;
524 }
525 list->buffer[list->head].len = len;
526 list->head = new_head;
527 kill_fasync(&list->fasync, SIGIO, POLL_IN);
528 }
529 spin_unlock_irqrestore(&dev->list_lock, flags);
530
531 wake_up_interruptible(&dev->wait);
532 return ret;
533 }
534 EXPORT_SYMBOL_GPL(hidraw_report_event);
535
536 int hidraw_connect(struct hid_device *hid)
537 {
538 int minor, result;
539 struct hidraw *dev;
540
541 /* we accept any HID device, all applications */
542
543 dev = kzalloc(sizeof(struct hidraw), GFP_KERNEL);
544 if (!dev)
545 return -ENOMEM;
546
547 result = -EINVAL;
548
549 mutex_lock(&minors_lock);
550
551 for (minor = 0; minor < HIDRAW_MAX_DEVICES; minor++) {
552 if (hidraw_table[minor])
553 continue;
554 hidraw_table[minor] = dev;
555 result = 0;
556 break;
557 }
558
559 if (result) {
560 mutex_unlock(&minors_lock);
561 kfree(dev);
562 goto out;
563 }
564
565 dev->dev = device_create(hidraw_class, &hid->dev, MKDEV(hidraw_major, minor),
566 NULL, "%s%d", "hidraw", minor);
567
568 if (IS_ERR(dev->dev)) {
569 hidraw_table[minor] = NULL;
570 mutex_unlock(&minors_lock);
571 result = PTR_ERR(dev->dev);
572 kfree(dev);
573 goto out;
574 }
575
576 init_waitqueue_head(&dev->wait);
577 spin_lock_init(&dev->list_lock);
578 INIT_LIST_HEAD(&dev->list);
579
580 dev->hid = hid;
581 dev->minor = minor;
582
583 dev->exist = 1;
584 hid->hidraw = dev;
585
586 mutex_unlock(&minors_lock);
587 out:
588 return result;
589
590 }
591 EXPORT_SYMBOL_GPL(hidraw_connect);
592
593 void hidraw_disconnect(struct hid_device *hid)
594 {
595 struct hidraw *hidraw = hid->hidraw;
596
597 mutex_lock(&minors_lock);
598
599 drop_ref(hidraw, 1);
600
601 mutex_unlock(&minors_lock);
602 }
603 EXPORT_SYMBOL_GPL(hidraw_disconnect);
604
605 int __init hidraw_init(void)
606 {
607 int result;
608 dev_t dev_id;
609
610 result = alloc_chrdev_region(&dev_id, HIDRAW_FIRST_MINOR,
611 HIDRAW_MAX_DEVICES, "hidraw");
612 if (result < 0) {
613 pr_warn("can't get major number\n");
614 goto out;
615 }
616
617 hidraw_major = MAJOR(dev_id);
618
619 hidraw_class = class_create(THIS_MODULE, "hidraw");
620 if (IS_ERR(hidraw_class)) {
621 result = PTR_ERR(hidraw_class);
622 goto error_cdev;
623 }
624
625 cdev_init(&hidraw_cdev, &hidraw_ops);
626 result = cdev_add(&hidraw_cdev, dev_id, HIDRAW_MAX_DEVICES);
627 if (result < 0)
628 goto error_class;
629
630 pr_info("raw HID events driver (C) Jiri Kosina\n");
631 out:
632 return result;
633
634 error_class:
635 class_destroy(hidraw_class);
636 error_cdev:
637 unregister_chrdev_region(dev_id, HIDRAW_MAX_DEVICES);
638 goto out;
639 }
640
641 void hidraw_exit(void)
642 {
643 dev_t dev_id = MKDEV(hidraw_major, 0);
644
645 cdev_del(&hidraw_cdev);
646 class_destroy(hidraw_class);
647 unregister_chrdev_region(dev_id, HIDRAW_MAX_DEVICES);
648
649 }
Linux with added FPC-III support