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22#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
23
24#include <linux/fs.h>
25#include <linux/module.h>
26#include <linux/errno.h>
27#include <linux/kernel.h>
28#include <linux/init.h>
29#include <linux/cdev.h>
30#include <linux/poll.h>
31#include <linux/device.h>
32#include <linux/major.h>
33#include <linux/slab.h>
34#include <linux/hid.h>
35#include <linux/mutex.h>
36#include <linux/sched.h>
37
38#include <linux/hidraw.h>
39
40static int hidraw_major;
41static struct cdev hidraw_cdev;
42static struct class *hidraw_class;
43static struct hidraw *hidraw_table[HIDRAW_MAX_DEVICES];
44static DEFINE_MUTEX(minors_lock);
45
46static ssize_t hidraw_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos)
47{
48 struct hidraw_list *list = file->private_data;
49 int ret = 0, len;
50 DECLARE_WAITQUEUE(wait, current);
51
52 mutex_lock(&list->read_mutex);
53
54 while (ret == 0) {
55 if (list->head == list->tail) {
56 add_wait_queue(&list->hidraw->wait, &wait);
57 set_current_state(TASK_INTERRUPTIBLE);
58
59 while (list->head == list->tail) {
60 if (signal_pending(current)) {
61 ret = -ERESTARTSYS;
62 break;
63 }
64 if (!list->hidraw->exist) {
65 ret = -EIO;
66 break;
67 }
68 if (file->f_flags & O_NONBLOCK) {
69 ret = -EAGAIN;
70 break;
71 }
72
73
74 mutex_unlock(&list->read_mutex);
75 schedule();
76 mutex_lock(&list->read_mutex);
77 set_current_state(TASK_INTERRUPTIBLE);
78 }
79
80 set_current_state(TASK_RUNNING);
81 remove_wait_queue(&list->hidraw->wait, &wait);
82 }
83
84 if (ret)
85 goto out;
86
87 len = list->buffer[list->tail].len > count ?
88 count : list->buffer[list->tail].len;
89
90 if (list->buffer[list->tail].value) {
91 if (copy_to_user(buffer, list->buffer[list->tail].value, len)) {
92 ret = -EFAULT;
93 goto out;
94 }
95 ret = len;
96 }
97
98 kfree(list->buffer[list->tail].value);
99 list->buffer[list->tail].value = NULL;
100 list->tail = (list->tail + 1) & (HIDRAW_BUFFER_SIZE - 1);
101 }
102out:
103 mutex_unlock(&list->read_mutex);
104 return ret;
105}
106
107
108
109static ssize_t hidraw_send_report(struct file *file, const char __user *buffer, size_t count, unsigned char report_type)
110{
111 unsigned int minor = iminor(file_inode(file));
112 struct hid_device *dev;
113 __u8 *buf;
114 int ret = 0;
115
116 if (!hidraw_table[minor]) {
117 ret = -ENODEV;
118 goto out;
119 }
120
121 dev = hidraw_table[minor]->hid;
122
123 if (!dev->hid_output_raw_report) {
124 ret = -ENODEV;
125 goto out;
126 }
127
128 if (count > HID_MAX_BUFFER_SIZE) {
129 hid_warn(dev, "pid %d passed too large report\n",
130 task_pid_nr(current));
131 ret = -EINVAL;
132 goto out;
133 }
134
135 if (count < 2) {
136 hid_warn(dev, "pid %d passed too short report\n",
137 task_pid_nr(current));
138 ret = -EINVAL;
139 goto out;
140 }
141
142 buf = kmalloc(count * sizeof(__u8), GFP_KERNEL);
143 if (!buf) {
144 ret = -ENOMEM;
145 goto out;
146 }
147
148 if (copy_from_user(buf, buffer, count)) {
149 ret = -EFAULT;
150 goto out_free;
151 }
152
153 ret = dev->hid_output_raw_report(dev, buf, count, report_type);
154out_free:
155 kfree(buf);
156out:
157 return ret;
158}
159
160
161static ssize_t hidraw_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
162{
163 ssize_t ret;
164 mutex_lock(&minors_lock);
165 ret = hidraw_send_report(file, buffer, count, HID_OUTPUT_REPORT);
166 mutex_unlock(&minors_lock);
167 return ret;
168}
169
170
171
172
173
174
175
176
177static 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 dev = hidraw_table[minor]->hid;
186
187 if (!dev->hid_get_raw_report) {
188 ret = -ENODEV;
189 goto out;
190 }
191
192 if (count > HID_MAX_BUFFER_SIZE) {
193 printk(KERN_WARNING "hidraw: pid %d passed too large report\n",
194 task_pid_nr(current));
195 ret = -EINVAL;
196 goto out;
197 }
198
199 if (count < 2) {
200 printk(KERN_WARNING "hidraw: pid %d passed too short report\n",
201 task_pid_nr(current));
202 ret = -EINVAL;
203 goto out;
204 }
205
206 buf = kmalloc(count * sizeof(__u8), GFP_KERNEL);
207 if (!buf) {
208 ret = -ENOMEM;
209 goto out;
210 }
211
212
213
214 if (copy_from_user(&report_number, buffer, 1)) {
215 ret = -EFAULT;
216 goto out_free;
217 }
218
219 ret = dev->hid_get_raw_report(dev, report_number, buf, count, report_type);
220
221 if (ret < 0)
222 goto out_free;
223
224 len = (ret < count) ? ret : count;
225
226 if (copy_to_user(buffer, buf, len)) {
227 ret = -EFAULT;
228 goto out_free;
229 }
230
231 ret = len;
232
233out_free:
234 kfree(buf);
235out:
236 return ret;
237}
238
239static unsigned int hidraw_poll(struct file *file, poll_table *wait)
240{
241 struct hidraw_list *list = file->private_data;
242
243 poll_wait(file, &list->hidraw->wait, wait);
244 if (list->head != list->tail)
245 return POLLIN | POLLRDNORM;
246 if (!list->hidraw->exist)
247 return POLLERR | POLLHUP;
248 return 0;
249}
250
251static int hidraw_open(struct inode *inode, struct file *file)
252{
253 unsigned int minor = iminor(inode);
254 struct hidraw *dev;
255 struct hidraw_list *list;
256 int err = 0;
257
258 if (!(list = kzalloc(sizeof(struct hidraw_list), GFP_KERNEL))) {
259 err = -ENOMEM;
260 goto out;
261 }
262
263 mutex_lock(&minors_lock);
264 if (!hidraw_table[minor]) {
265 err = -ENODEV;
266 goto out_unlock;
267 }
268
269 list->hidraw = hidraw_table[minor];
270 mutex_init(&list->read_mutex);
271 list_add_tail(&list->node, &hidraw_table[minor]->list);
272 file->private_data = list;
273
274 dev = hidraw_table[minor];
275 if (!dev->open++) {
276 err = hid_hw_power(dev->hid, PM_HINT_FULLON);
277 if (err < 0) {
278 dev->open--;
279 goto out_unlock;
280 }
281
282 err = hid_hw_open(dev->hid);
283 if (err < 0) {
284 hid_hw_power(dev->hid, PM_HINT_NORMAL);
285 dev->open--;
286 }
287 }
288
289out_unlock:
290 mutex_unlock(&minors_lock);
291out:
292 if (err < 0)
293 kfree(list);
294 return err;
295
296}
297
298static int hidraw_fasync(int fd, struct file *file, int on)
299{
300 struct hidraw_list *list = file->private_data;
301
302 return fasync_helper(fd, file, on, &list->fasync);
303}
304
305static int hidraw_release(struct inode * inode, struct file * file)
306{
307 unsigned int minor = iminor(inode);
308 struct hidraw *dev;
309 struct hidraw_list *list = file->private_data;
310 int ret;
311 int i;
312
313 mutex_lock(&minors_lock);
314 if (!hidraw_table[minor]) {
315 ret = -ENODEV;
316 goto unlock;
317 }
318
319 list_del(&list->node);
320 dev = hidraw_table[minor];
321 if (!--dev->open) {
322 if (list->hidraw->exist) {
323 hid_hw_power(dev->hid, PM_HINT_NORMAL);
324 hid_hw_close(dev->hid);
325 } else {
326 kfree(list->hidraw);
327 }
328 }
329
330 for (i = 0; i < HIDRAW_BUFFER_SIZE; ++i)
331 kfree(list->buffer[i].value);
332 kfree(list);
333 ret = 0;
334unlock:
335 mutex_unlock(&minors_lock);
336
337 return ret;
338}
339
340static long hidraw_ioctl(struct file *file, unsigned int cmd,
341 unsigned long arg)
342{
343 struct inode *inode = file_inode(file);
344 unsigned int minor = iminor(inode);
345 long ret = 0;
346 struct hidraw *dev;
347 void __user *user_arg = (void __user*) arg;
348
349 mutex_lock(&minors_lock);
350 dev = hidraw_table[minor];
351 if (!dev) {
352 ret = -ENODEV;
353 goto out;
354 }
355
356 switch (cmd) {
357 case HIDIOCGRDESCSIZE:
358 if (put_user(dev->hid->rsize, (int __user *)arg))
359 ret = -EFAULT;
360 break;
361
362 case HIDIOCGRDESC:
363 {
364 __u32 len;
365
366 if (get_user(len, (int __user *)arg))
367 ret = -EFAULT;
368 else if (len > HID_MAX_DESCRIPTOR_SIZE - 1)
369 ret = -EINVAL;
370 else if (copy_to_user(user_arg + offsetof(
371 struct hidraw_report_descriptor,
372 value[0]),
373 dev->hid->rdesc,
374 min(dev->hid->rsize, len)))
375 ret = -EFAULT;
376 break;
377 }
378 case HIDIOCGRAWINFO:
379 {
380 struct hidraw_devinfo dinfo;
381
382 dinfo.bustype = dev->hid->bus;
383 dinfo.vendor = dev->hid->vendor;
384 dinfo.product = dev->hid->product;
385 if (copy_to_user(user_arg, &dinfo, sizeof(dinfo)))
386 ret = -EFAULT;
387 break;
388 }
389 default:
390 {
391 struct hid_device *hid = dev->hid;
392 if (_IOC_TYPE(cmd) != 'H') {
393 ret = -EINVAL;
394 break;
395 }
396
397 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCSFEATURE(0))) {
398 int len = _IOC_SIZE(cmd);
399 ret = hidraw_send_report(file, user_arg, len, HID_FEATURE_REPORT);
400 break;
401 }
402 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGFEATURE(0))) {
403 int len = _IOC_SIZE(cmd);
404 ret = hidraw_get_report(file, user_arg, len, HID_FEATURE_REPORT);
405 break;
406 }
407
408
409 if (_IOC_DIR(cmd) != _IOC_READ) {
410 ret = -EINVAL;
411 break;
412 }
413
414 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGRAWNAME(0))) {
415 int len = strlen(hid->name) + 1;
416 if (len > _IOC_SIZE(cmd))
417 len = _IOC_SIZE(cmd);
418 ret = copy_to_user(user_arg, hid->name, len) ?
419 -EFAULT : len;
420 break;
421 }
422
423 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGRAWPHYS(0))) {
424 int len = strlen(hid->phys) + 1;
425 if (len > _IOC_SIZE(cmd))
426 len = _IOC_SIZE(cmd);
427 ret = copy_to_user(user_arg, hid->phys, len) ?
428 -EFAULT : len;
429 break;
430 }
431 }
432
433 ret = -ENOTTY;
434 }
435out:
436 mutex_unlock(&minors_lock);
437 return ret;
438}
439
440static const struct file_operations hidraw_ops = {
441 .owner = THIS_MODULE,
442 .read = hidraw_read,
443 .write = hidraw_write,
444 .poll = hidraw_poll,
445 .open = hidraw_open,
446 .release = hidraw_release,
447 .unlocked_ioctl = hidraw_ioctl,
448 .fasync = hidraw_fasync,
449#ifdef CONFIG_COMPAT
450 .compat_ioctl = hidraw_ioctl,
451#endif
452 .llseek = noop_llseek,
453};
454
455int hidraw_report_event(struct hid_device *hid, u8 *data, int len)
456{
457 struct hidraw *dev = hid->hidraw;
458 struct hidraw_list *list;
459 int ret = 0;
460
461 list_for_each_entry(list, &dev->list, node) {
462 int new_head = (list->head + 1) & (HIDRAW_BUFFER_SIZE - 1);
463
464 if (new_head == list->tail)
465 continue;
466
467 if (!(list->buffer[list->head].value = kmemdup(data, len, GFP_ATOMIC))) {
468 ret = -ENOMEM;
469 break;
470 }
471 list->buffer[list->head].len = len;
472 list->head = new_head;
473 kill_fasync(&list->fasync, SIGIO, POLL_IN);
474 }
475
476 wake_up_interruptible(&dev->wait);
477 return ret;
478}
479EXPORT_SYMBOL_GPL(hidraw_report_event);
480
481int hidraw_connect(struct hid_device *hid)
482{
483 int minor, result;
484 struct hidraw *dev;
485
486
487
488 dev = kzalloc(sizeof(struct hidraw), GFP_KERNEL);
489 if (!dev)
490 return -ENOMEM;
491
492 result = -EINVAL;
493
494 mutex_lock(&minors_lock);
495
496 for (minor = 0; minor < HIDRAW_MAX_DEVICES; minor++) {
497 if (hidraw_table[minor])
498 continue;
499 hidraw_table[minor] = dev;
500 result = 0;
501 break;
502 }
503
504 if (result) {
505 mutex_unlock(&minors_lock);
506 kfree(dev);
507 goto out;
508 }
509
510 dev->dev = device_create(hidraw_class, &hid->dev, MKDEV(hidraw_major, minor),
511 NULL, "%s%d", "hidraw", minor);
512
513 if (IS_ERR(dev->dev)) {
514 hidraw_table[minor] = NULL;
515 mutex_unlock(&minors_lock);
516 result = PTR_ERR(dev->dev);
517 kfree(dev);
518 goto out;
519 }
520
521 mutex_unlock(&minors_lock);
522 init_waitqueue_head(&dev->wait);
523 INIT_LIST_HEAD(&dev->list);
524
525 dev->hid = hid;
526 dev->minor = minor;
527
528 dev->exist = 1;
529 hid->hidraw = dev;
530
531out:
532 return result;
533
534}
535EXPORT_SYMBOL_GPL(hidraw_connect);
536
537void hidraw_disconnect(struct hid_device *hid)
538{
539 struct hidraw *hidraw = hid->hidraw;
540
541 mutex_lock(&minors_lock);
542 hidraw->exist = 0;
543
544 device_destroy(hidraw_class, MKDEV(hidraw_major, hidraw->minor));
545
546 hidraw_table[hidraw->minor] = NULL;
547
548 if (hidraw->open) {
549 hid_hw_close(hid);
550 wake_up_interruptible(&hidraw->wait);
551 } else {
552 kfree(hidraw);
553 }
554 mutex_unlock(&minors_lock);
555}
556EXPORT_SYMBOL_GPL(hidraw_disconnect);
557
558int __init hidraw_init(void)
559{
560 int result;
561 dev_t dev_id;
562
563 result = alloc_chrdev_region(&dev_id, HIDRAW_FIRST_MINOR,
564 HIDRAW_MAX_DEVICES, "hidraw");
565
566 hidraw_major = MAJOR(dev_id);
567
568 if (result < 0) {
569 pr_warn("can't get major number\n");
570 goto out;
571 }
572
573 hidraw_class = class_create(THIS_MODULE, "hidraw");
574 if (IS_ERR(hidraw_class)) {
575 result = PTR_ERR(hidraw_class);
576 goto error_cdev;
577 }
578
579 cdev_init(&hidraw_cdev, &hidraw_ops);
580 result = cdev_add(&hidraw_cdev, dev_id, HIDRAW_MAX_DEVICES);
581 if (result < 0)
582 goto error_class;
583
584 printk(KERN_INFO "hidraw: raw HID events driver (C) Jiri Kosina\n");
585out:
586 return result;
587
588error_class:
589 class_destroy(hidraw_class);
590error_cdev:
591 unregister_chrdev_region(dev_id, HIDRAW_MAX_DEVICES);
592 goto out;
593}
594
595void hidraw_exit(void)
596{
597 dev_t dev_id = MKDEV(hidraw_major, 0);
598
599 cdev_del(&hidraw_cdev);
600 class_destroy(hidraw_class);
601 unregister_chrdev_region(dev_id, HIDRAW_MAX_DEVICES);
602
603}
604
