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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 (file->f_flags & O_NONBLOCK) {
61 ret = -EAGAIN;
62 break;
63 }
64 if (signal_pending(current)) {
65 ret = -ERESTARTSYS;
66 break;
67 }
68 if (!list->hidraw->exist) {
69 ret = -EIO;
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 (copy_to_user(buffer, list->buffer[list->tail].value, len)) {
91 ret = -EFAULT;
92 goto out;
93 }
94 ret = len;
95
96 kfree(list->buffer[list->tail].value);
97 list->tail = (list->tail + 1) & (HIDRAW_BUFFER_SIZE - 1);
98 }
99out:
100 mutex_unlock(&list->read_mutex);
101 return ret;
102}
103
104
105
106static ssize_t hidraw_send_report(struct file *file, const char __user *buffer, size_t count, unsigned char report_type)
107{
108 unsigned int minor = iminor(file->f_path.dentry->d_inode);
109 struct hid_device *dev;
110 __u8 *buf;
111 int ret = 0;
112
113 if (!hidraw_table[minor]) {
114 ret = -ENODEV;
115 goto out;
116 }
117
118 dev = hidraw_table[minor]->hid;
119
120 if (!dev->hid_output_raw_report) {
121 ret = -ENODEV;
122 goto out;
123 }
124
125 if (count > HID_MAX_BUFFER_SIZE) {
126 hid_warn(dev, "pid %d passed too large report\n",
127 task_pid_nr(current));
128 ret = -EINVAL;
129 goto out;
130 }
131
132 if (count < 2) {
133 hid_warn(dev, "pid %d passed too short report\n",
134 task_pid_nr(current));
135 ret = -EINVAL;
136 goto out;
137 }
138
139 buf = kmalloc(count * sizeof(__u8), GFP_KERNEL);
140 if (!buf) {
141 ret = -ENOMEM;
142 goto out;
143 }
144
145 if (copy_from_user(buf, buffer, count)) {
146 ret = -EFAULT;
147 goto out_free;
148 }
149
150 ret = dev->hid_output_raw_report(dev, buf, count, report_type);
151out_free:
152 kfree(buf);
153out:
154 return ret;
155}
156
157
158static ssize_t hidraw_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
159{
160 ssize_t ret;
161 mutex_lock(&minors_lock);
162 ret = hidraw_send_report(file, buffer, count, HID_OUTPUT_REPORT);
163 mutex_unlock(&minors_lock);
164 return ret;
165}
166
167
168
169
170
171
172
173
174static ssize_t hidraw_get_report(struct file *file, char __user *buffer, size_t count, unsigned char report_type)
175{
176 unsigned int minor = iminor(file->f_path.dentry->d_inode);
177 struct hid_device *dev;
178 __u8 *buf;
179 int ret = 0, len;
180 unsigned char report_number;
181
182 dev = hidraw_table[minor]->hid;
183
184 if (!dev->hid_get_raw_report) {
185 ret = -ENODEV;
186 goto out;
187 }
188
189 if (count > HID_MAX_BUFFER_SIZE) {
190 printk(KERN_WARNING "hidraw: pid %d passed too large report\n",
191 task_pid_nr(current));
192 ret = -EINVAL;
193 goto out;
194 }
195
196 if (count < 2) {
197 printk(KERN_WARNING "hidraw: pid %d passed too short report\n",
198 task_pid_nr(current));
199 ret = -EINVAL;
200 goto out;
201 }
202
203 buf = kmalloc(count * sizeof(__u8), GFP_KERNEL);
204 if (!buf) {
205 ret = -ENOMEM;
206 goto out;
207 }
208
209
210
211 if (copy_from_user(&report_number, buffer, 1)) {
212 ret = -EFAULT;
213 goto out_free;
214 }
215
216 ret = dev->hid_get_raw_report(dev, report_number, buf, count, report_type);
217
218 if (ret < 0)
219 goto out_free;
220
221 len = (ret < count) ? ret : count;
222
223 if (copy_to_user(buffer, buf, len)) {
224 ret = -EFAULT;
225 goto out_free;
226 }
227
228 ret = len;
229
230out_free:
231 kfree(buf);
232out:
233 return ret;
234}
235
236static unsigned int hidraw_poll(struct file *file, poll_table *wait)
237{
238 struct hidraw_list *list = file->private_data;
239
240 poll_wait(file, &list->hidraw->wait, wait);
241 if (list->head != list->tail)
242 return POLLIN | POLLRDNORM;
243 if (!list->hidraw->exist)
244 return POLLERR | POLLHUP;
245 return 0;
246}
247
248static int hidraw_open(struct inode *inode, struct file *file)
249{
250 unsigned int minor = iminor(inode);
251 struct hidraw *dev;
252 struct hidraw_list *list;
253 int err = 0;
254
255 if (!(list = kzalloc(sizeof(struct hidraw_list), GFP_KERNEL))) {
256 err = -ENOMEM;
257 goto out;
258 }
259
260 mutex_lock(&minors_lock);
261 if (!hidraw_table[minor]) {
262 kfree(list);
263 err = -ENODEV;
264 goto out_unlock;
265 }
266
267 list->hidraw = hidraw_table[minor];
268 mutex_init(&list->read_mutex);
269 list_add_tail(&list->node, &hidraw_table[minor]->list);
270 file->private_data = list;
271
272 dev = hidraw_table[minor];
273 if (!dev->open++) {
274 err = hid_hw_power(dev->hid, PM_HINT_FULLON);
275 if (err < 0)
276 goto out_unlock;
277
278 err = hid_hw_open(dev->hid);
279 if (err < 0) {
280 hid_hw_power(dev->hid, PM_HINT_NORMAL);
281 dev->open--;
282 }
283 }
284
285out_unlock:
286 mutex_unlock(&minors_lock);
287out:
288 return err;
289
290}
291
292static int hidraw_release(struct inode * inode, struct file * file)
293{
294 unsigned int minor = iminor(inode);
295 struct hidraw *dev;
296 struct hidraw_list *list = file->private_data;
297 int ret;
298
299 mutex_lock(&minors_lock);
300 if (!hidraw_table[minor]) {
301 ret = -ENODEV;
302 goto unlock;
303 }
304
305 list_del(&list->node);
306 dev = hidraw_table[minor];
307 if (!--dev->open) {
308 if (list->hidraw->exist) {
309 hid_hw_power(dev->hid, PM_HINT_NORMAL);
310 hid_hw_close(dev->hid);
311 } else {
312 kfree(list->hidraw);
313 }
314 }
315 kfree(list);
316 ret = 0;
317unlock:
318 mutex_unlock(&minors_lock);
319
320 return ret;
321}
322
323static long hidraw_ioctl(struct file *file, unsigned int cmd,
324 unsigned long arg)
325{
326 struct inode *inode = file->f_path.dentry->d_inode;
327 unsigned int minor = iminor(inode);
328 long ret = 0;
329 struct hidraw *dev;
330 void __user *user_arg = (void __user*) arg;
331
332 mutex_lock(&minors_lock);
333 dev = hidraw_table[minor];
334 if (!dev) {
335 ret = -ENODEV;
336 goto out;
337 }
338
339 switch (cmd) {
340 case HIDIOCGRDESCSIZE:
341 if (put_user(dev->hid->rsize, (int __user *)arg))
342 ret = -EFAULT;
343 break;
344
345 case HIDIOCGRDESC:
346 {
347 __u32 len;
348
349 if (get_user(len, (int __user *)arg))
350 ret = -EFAULT;
351 else if (len > HID_MAX_DESCRIPTOR_SIZE - 1)
352 ret = -EINVAL;
353 else if (copy_to_user(user_arg + offsetof(
354 struct hidraw_report_descriptor,
355 value[0]),
356 dev->hid->rdesc,
357 min(dev->hid->rsize, len)))
358 ret = -EFAULT;
359 break;
360 }
361 case HIDIOCGRAWINFO:
362 {
363 struct hidraw_devinfo dinfo;
364
365 dinfo.bustype = dev->hid->bus;
366 dinfo.vendor = dev->hid->vendor;
367 dinfo.product = dev->hid->product;
368 if (copy_to_user(user_arg, &dinfo, sizeof(dinfo)))
369 ret = -EFAULT;
370 break;
371 }
372 default:
373 {
374 struct hid_device *hid = dev->hid;
375 if (_IOC_TYPE(cmd) != 'H') {
376 ret = -EINVAL;
377 break;
378 }
379
380 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCSFEATURE(0))) {
381 int len = _IOC_SIZE(cmd);
382 ret = hidraw_send_report(file, user_arg, len, HID_FEATURE_REPORT);
383 break;
384 }
385 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGFEATURE(0))) {
386 int len = _IOC_SIZE(cmd);
387 ret = hidraw_get_report(file, user_arg, len, HID_FEATURE_REPORT);
388 break;
389 }
390
391
392 if (_IOC_DIR(cmd) != _IOC_READ) {
393 ret = -EINVAL;
394 break;
395 }
396
397 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGRAWNAME(0))) {
398 int len;
399 if (!hid->name) {
400 ret = 0;
401 break;
402 }
403 len = strlen(hid->name) + 1;
404 if (len > _IOC_SIZE(cmd))
405 len = _IOC_SIZE(cmd);
406 ret = copy_to_user(user_arg, hid->name, len) ?
407 -EFAULT : len;
408 break;
409 }
410
411 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGRAWPHYS(0))) {
412 int len;
413 if (!hid->phys) {
414 ret = 0;
415 break;
416 }
417 len = strlen(hid->phys) + 1;
418 if (len > _IOC_SIZE(cmd))
419 len = _IOC_SIZE(cmd);
420 ret = copy_to_user(user_arg, hid->phys, len) ?
421 -EFAULT : len;
422 break;
423 }
424 }
425
426 ret = -ENOTTY;
427 }
428out:
429 mutex_unlock(&minors_lock);
430 return ret;
431}
432
433static const struct file_operations hidraw_ops = {
434 .owner = THIS_MODULE,
435 .read = hidraw_read,
436 .write = hidraw_write,
437 .poll = hidraw_poll,
438 .open = hidraw_open,
439 .release = hidraw_release,
440 .unlocked_ioctl = hidraw_ioctl,
441#ifdef CONFIG_COMPAT
442 .compat_ioctl = hidraw_ioctl,
443#endif
444 .llseek = noop_llseek,
445};
446
447void hidraw_report_event(struct hid_device *hid, u8 *data, int len)
448{
449 struct hidraw *dev = hid->hidraw;
450 struct hidraw_list *list;
451
452 list_for_each_entry(list, &dev->list, node) {
453 list->buffer[list->head].value = kmemdup(data, len, GFP_ATOMIC);
454 list->buffer[list->head].len = len;
455 list->head = (list->head + 1) & (HIDRAW_BUFFER_SIZE - 1);
456 kill_fasync(&list->fasync, SIGIO, POLL_IN);
457 }
458
459 wake_up_interruptible(&dev->wait);
460}
461EXPORT_SYMBOL_GPL(hidraw_report_event);
462
463int hidraw_connect(struct hid_device *hid)
464{
465 int minor, result;
466 struct hidraw *dev;
467
468
469
470 dev = kzalloc(sizeof(struct hidraw), GFP_KERNEL);
471 if (!dev)
472 return -ENOMEM;
473
474 result = -EINVAL;
475
476 mutex_lock(&minors_lock);
477
478 for (minor = 0; minor < HIDRAW_MAX_DEVICES; minor++) {
479 if (hidraw_table[minor])
480 continue;
481 hidraw_table[minor] = dev;
482 result = 0;
483 break;
484 }
485
486 if (result) {
487 mutex_unlock(&minors_lock);
488 kfree(dev);
489 goto out;
490 }
491
492 dev->dev = device_create(hidraw_class, &hid->dev, MKDEV(hidraw_major, minor),
493 NULL, "%s%d", "hidraw", minor);
494
495 if (IS_ERR(dev->dev)) {
496 hidraw_table[minor] = NULL;
497 mutex_unlock(&minors_lock);
498 result = PTR_ERR(dev->dev);
499 kfree(dev);
500 goto out;
501 }
502
503 mutex_unlock(&minors_lock);
504 init_waitqueue_head(&dev->wait);
505 INIT_LIST_HEAD(&dev->list);
506
507 dev->hid = hid;
508 dev->minor = minor;
509
510 dev->exist = 1;
511 hid->hidraw = dev;
512
513out:
514 return result;
515
516}
517EXPORT_SYMBOL_GPL(hidraw_connect);
518
519void hidraw_disconnect(struct hid_device *hid)
520{
521 struct hidraw *hidraw = hid->hidraw;
522
523 hidraw->exist = 0;
524
525 device_destroy(hidraw_class, MKDEV(hidraw_major, hidraw->minor));
526
527 mutex_lock(&minors_lock);
528 hidraw_table[hidraw->minor] = NULL;
529 mutex_unlock(&minors_lock);
530
531 if (hidraw->open) {
532 hid_hw_close(hid);
533 wake_up_interruptible(&hidraw->wait);
534 } else {
535 kfree(hidraw);
536 }
537}
538EXPORT_SYMBOL_GPL(hidraw_disconnect);
539
540int __init hidraw_init(void)
541{
542 int result;
543 dev_t dev_id;
544
545 result = alloc_chrdev_region(&dev_id, HIDRAW_FIRST_MINOR,
546 HIDRAW_MAX_DEVICES, "hidraw");
547
548 hidraw_major = MAJOR(dev_id);
549
550 if (result < 0) {
551 pr_warn("can't get major number\n");
552 result = 0;
553 goto out;
554 }
555
556 hidraw_class = class_create(THIS_MODULE, "hidraw");
557 if (IS_ERR(hidraw_class)) {
558 result = PTR_ERR(hidraw_class);
559 unregister_chrdev(hidraw_major, "hidraw");
560 goto out;
561 }
562
563 cdev_init(&hidraw_cdev, &hidraw_ops);
564 cdev_add(&hidraw_cdev, dev_id, HIDRAW_MAX_DEVICES);
565out:
566 return result;
567}
568
569void hidraw_exit(void)
570{
571 dev_t dev_id = MKDEV(hidraw_major, 0);
572
573 cdev_del(&hidraw_cdev);
574 class_destroy(hidraw_class);
575 unregister_chrdev_region(dev_id, HIDRAW_MAX_DEVICES);
576
577}
578
