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1/*
2 * HID raw devices, giving access to raw HID events.
3 *
4 * In comparison to hiddev, this device does not process the
5 * hid events at all (no parsing, no lookups). This lets applications
6 * to work on raw hid events as they want to, and avoids a need to
7 * use a transport-specific userspace libhid/libusb libraries.
8 *
9 * Copyright (c) 2007 Jiri Kosina
10 */
11
12/*
13 * This program is free software; you can redistribute it and/or modify it
14 * under the terms and conditions of the GNU General Public License,
15 * version 2, as published by the Free Software Foundation.
16 *
17 * You should have received a copy of the GNU General Public License along with
18 * this program; if not, write to the Free Software Foundation, Inc.,
19 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
20 */
21
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 /* allow O_NONBLOCK to work well from other threads */
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/* The first byte is expected to be a report number.
105 * This function is to be called with the minors_lock mutex held */
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/* the first byte is expected to be a report number */
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/* This function performs a Get_Report transfer over the control endpoint
169 * per section 7.2.1 of the HID specification, version 1.1. The first byte
170 * of buffer is the report number to request, or 0x0 if the defice does not
171 * use numbered reports. The report_type parameter can be HID_FEATURE_REPORT
172 * or HID_INPUT_REPORT. This function is to be called with the minors_lock
173 * mutex held. */
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 /* Read the first byte from the user. This is the report number,
210 * which is passed to dev->hid_get_raw_report(). */
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 /* Begin Read-only ioctls. */
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 = strlen(hid->name) + 1;
399 if (len > _IOC_SIZE(cmd))
400 len = _IOC_SIZE(cmd);
401 ret = copy_to_user(user_arg, hid->name, len) ?
402 -EFAULT : len;
403 break;
404 }
405
406 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGRAWPHYS(0))) {
407 int len = strlen(hid->phys) + 1;
408 if (len > _IOC_SIZE(cmd))
409 len = _IOC_SIZE(cmd);
410 ret = copy_to_user(user_arg, hid->phys, len) ?
411 -EFAULT : len;
412 break;
413 }
414 }
415
416 ret = -ENOTTY;
417 }
418out:
419 mutex_unlock(&minors_lock);
420 return ret;
421}
422
423static const struct file_operations hidraw_ops = {
424 .owner = THIS_MODULE,
425 .read = hidraw_read,
426 .write = hidraw_write,
427 .poll = hidraw_poll,
428 .open = hidraw_open,
429 .release = hidraw_release,
430 .unlocked_ioctl = hidraw_ioctl,
431#ifdef CONFIG_COMPAT
432 .compat_ioctl = hidraw_ioctl,
433#endif
434 .llseek = noop_llseek,
435};
436
437void hidraw_report_event(struct hid_device *hid, u8 *data, int len)
438{
439 struct hidraw *dev = hid->hidraw;
440 struct hidraw_list *list;
441
442 list_for_each_entry(list, &dev->list, node) {
443 list->buffer[list->head].value = kmemdup(data, len, GFP_ATOMIC);
444 list->buffer[list->head].len = len;
445 list->head = (list->head + 1) & (HIDRAW_BUFFER_SIZE - 1);
446 kill_fasync(&list->fasync, SIGIO, POLL_IN);
447 }
448
449 wake_up_interruptible(&dev->wait);
450}
451EXPORT_SYMBOL_GPL(hidraw_report_event);
452
453int hidraw_connect(struct hid_device *hid)
454{
455 int minor, result;
456 struct hidraw *dev;
457
458 /* we accept any HID device, no matter the applications */
459
460 dev = kzalloc(sizeof(struct hidraw), GFP_KERNEL);
461 if (!dev)
462 return -ENOMEM;
463
464 result = -EINVAL;
465
466 mutex_lock(&minors_lock);
467
468 for (minor = 0; minor < HIDRAW_MAX_DEVICES; minor++) {
469 if (hidraw_table[minor])
470 continue;
471 hidraw_table[minor] = dev;
472 result = 0;
473 break;
474 }
475
476 if (result) {
477 mutex_unlock(&minors_lock);
478 kfree(dev);
479 goto out;
480 }
481
482 dev->dev = device_create(hidraw_class, &hid->dev, MKDEV(hidraw_major, minor),
483 NULL, "%s%d", "hidraw", minor);
484
485 if (IS_ERR(dev->dev)) {
486 hidraw_table[minor] = NULL;
487 mutex_unlock(&minors_lock);
488 result = PTR_ERR(dev->dev);
489 kfree(dev);
490 goto out;
491 }
492
493 mutex_unlock(&minors_lock);
494 init_waitqueue_head(&dev->wait);
495 INIT_LIST_HEAD(&dev->list);
496
497 dev->hid = hid;
498 dev->minor = minor;
499
500 dev->exist = 1;
501 hid->hidraw = dev;
502
503out:
504 return result;
505
506}
507EXPORT_SYMBOL_GPL(hidraw_connect);
508
509void hidraw_disconnect(struct hid_device *hid)
510{
511 struct hidraw *hidraw = hid->hidraw;
512
513 hidraw->exist = 0;
514
515 device_destroy(hidraw_class, MKDEV(hidraw_major, hidraw->minor));
516
517 mutex_lock(&minors_lock);
518 hidraw_table[hidraw->minor] = NULL;
519 mutex_unlock(&minors_lock);
520
521 if (hidraw->open) {
522 hid_hw_close(hid);
523 wake_up_interruptible(&hidraw->wait);
524 } else {
525 kfree(hidraw);
526 }
527}
528EXPORT_SYMBOL_GPL(hidraw_disconnect);
529
530int __init hidraw_init(void)
531{
532 int result;
533 dev_t dev_id;
534
535 result = alloc_chrdev_region(&dev_id, HIDRAW_FIRST_MINOR,
536 HIDRAW_MAX_DEVICES, "hidraw");
537
538 hidraw_major = MAJOR(dev_id);
539
540 if (result < 0) {
541 pr_warn("can't get major number\n");
542 result = 0;
543 goto out;
544 }
545
546 hidraw_class = class_create(THIS_MODULE, "hidraw");
547 if (IS_ERR(hidraw_class)) {
548 result = PTR_ERR(hidraw_class);
549 unregister_chrdev(hidraw_major, "hidraw");
550 goto out;
551 }
552
553 cdev_init(&hidraw_cdev, &hidraw_ops);
554 cdev_add(&hidraw_cdev, dev_id, HIDRAW_MAX_DEVICES);
555out:
556 return result;
557}
558
559void hidraw_exit(void)
560{
561 dev_t dev_id = MKDEV(hidraw_major, 0);
562
563 cdev_del(&hidraw_cdev);
564 class_destroy(hidraw_class);
565 unregister_chrdev_region(dev_id, HIDRAW_MAX_DEVICES);
566
567}
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
33static int hidraw_major;
34static struct cdev hidraw_cdev;
35static struct class *hidraw_class;
36static struct hidraw *hidraw_table[HIDRAW_MAX_DEVICES];
37static DECLARE_RWSEM(minors_rwsem);
38
39static 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 }
95out:
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 */
103static 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_rwsem);
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
154out_free:
155 kfree(buf);
156out:
157 return ret;
158}
159
160static ssize_t hidraw_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
161{
162 ssize_t ret;
163 down_read(&minors_rwsem);
164 ret = hidraw_send_report(file, buffer, count, HID_OUTPUT_REPORT);
165 up_read(&minors_rwsem);
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 */
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 lockdep_assert_held(&minors_rwsem);
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
243out_free:
244 kfree(buf);
245out:
246 return ret;
247}
248
249static __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
262static 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 down_read(&minors_rwsem);
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;
303out_unlock:
304 up_read(&minors_rwsem);
305out:
306 if (err < 0)
307 kfree(list);
308 return err;
309
310}
311
312static 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
319static 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
344static 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 down_write(&minors_rwsem);
351
352 spin_lock_irqsave(&hidraw_table[minor]->list_lock, flags);
353 for (int i = list->tail; i < list->head; i++)
354 kfree(list->buffer[i].value);
355 list_del(&list->node);
356 spin_unlock_irqrestore(&hidraw_table[minor]->list_lock, flags);
357 kfree(list);
358
359 drop_ref(hidraw_table[minor], 0);
360
361 up_write(&minors_rwsem);
362 return 0;
363}
364
365static long hidraw_ioctl(struct file *file, unsigned int cmd,
366 unsigned long arg)
367{
368 struct inode *inode = file_inode(file);
369 unsigned int minor = iminor(inode);
370 long ret = 0;
371 struct hidraw *dev;
372 void __user *user_arg = (void __user*) arg;
373
374 down_read(&minors_rwsem);
375 dev = hidraw_table[minor];
376 if (!dev || !dev->exist) {
377 ret = -ENODEV;
378 goto out;
379 }
380
381 switch (cmd) {
382 case HIDIOCGRDESCSIZE:
383 if (put_user(dev->hid->rsize, (int __user *)arg))
384 ret = -EFAULT;
385 break;
386
387 case HIDIOCGRDESC:
388 {
389 __u32 len;
390
391 if (get_user(len, (int __user *)arg))
392 ret = -EFAULT;
393 else if (len > HID_MAX_DESCRIPTOR_SIZE - 1)
394 ret = -EINVAL;
395 else if (copy_to_user(user_arg + offsetof(
396 struct hidraw_report_descriptor,
397 value[0]),
398 dev->hid->rdesc,
399 min(dev->hid->rsize, len)))
400 ret = -EFAULT;
401 break;
402 }
403 case HIDIOCGRAWINFO:
404 {
405 struct hidraw_devinfo dinfo;
406
407 dinfo.bustype = dev->hid->bus;
408 dinfo.vendor = dev->hid->vendor;
409 dinfo.product = dev->hid->product;
410 if (copy_to_user(user_arg, &dinfo, sizeof(dinfo)))
411 ret = -EFAULT;
412 break;
413 }
414 default:
415 {
416 struct hid_device *hid = dev->hid;
417 if (_IOC_TYPE(cmd) != 'H') {
418 ret = -EINVAL;
419 break;
420 }
421
422 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCSFEATURE(0))) {
423 int len = _IOC_SIZE(cmd);
424 ret = hidraw_send_report(file, user_arg, len, HID_FEATURE_REPORT);
425 break;
426 }
427 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGFEATURE(0))) {
428 int len = _IOC_SIZE(cmd);
429 ret = hidraw_get_report(file, user_arg, len, HID_FEATURE_REPORT);
430 break;
431 }
432
433 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCSINPUT(0))) {
434 int len = _IOC_SIZE(cmd);
435 ret = hidraw_send_report(file, user_arg, len, HID_INPUT_REPORT);
436 break;
437 }
438 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGINPUT(0))) {
439 int len = _IOC_SIZE(cmd);
440 ret = hidraw_get_report(file, user_arg, len, HID_INPUT_REPORT);
441 break;
442 }
443
444 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCSOUTPUT(0))) {
445 int len = _IOC_SIZE(cmd);
446 ret = hidraw_send_report(file, user_arg, len, HID_OUTPUT_REPORT);
447 break;
448 }
449 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGOUTPUT(0))) {
450 int len = _IOC_SIZE(cmd);
451 ret = hidraw_get_report(file, user_arg, len, HID_OUTPUT_REPORT);
452 break;
453 }
454
455 /* Begin Read-only ioctls. */
456 if (_IOC_DIR(cmd) != _IOC_READ) {
457 ret = -EINVAL;
458 break;
459 }
460
461 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGRAWNAME(0))) {
462 int len = strlen(hid->name) + 1;
463 if (len > _IOC_SIZE(cmd))
464 len = _IOC_SIZE(cmd);
465 ret = copy_to_user(user_arg, hid->name, len) ?
466 -EFAULT : len;
467 break;
468 }
469
470 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGRAWPHYS(0))) {
471 int len = strlen(hid->phys) + 1;
472 if (len > _IOC_SIZE(cmd))
473 len = _IOC_SIZE(cmd);
474 ret = copy_to_user(user_arg, hid->phys, len) ?
475 -EFAULT : len;
476 break;
477 }
478
479 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGRAWUNIQ(0))) {
480 int len = strlen(hid->uniq) + 1;
481 if (len > _IOC_SIZE(cmd))
482 len = _IOC_SIZE(cmd);
483 ret = copy_to_user(user_arg, hid->uniq, len) ?
484 -EFAULT : len;
485 break;
486 }
487 }
488
489 ret = -ENOTTY;
490 }
491out:
492 up_read(&minors_rwsem);
493 return ret;
494}
495
496static const struct file_operations hidraw_ops = {
497 .owner = THIS_MODULE,
498 .read = hidraw_read,
499 .write = hidraw_write,
500 .poll = hidraw_poll,
501 .open = hidraw_open,
502 .release = hidraw_release,
503 .unlocked_ioctl = hidraw_ioctl,
504 .fasync = hidraw_fasync,
505 .compat_ioctl = compat_ptr_ioctl,
506 .llseek = noop_llseek,
507};
508
509int hidraw_report_event(struct hid_device *hid, u8 *data, int len)
510{
511 struct hidraw *dev = hid->hidraw;
512 struct hidraw_list *list;
513 int ret = 0;
514 unsigned long flags;
515
516 spin_lock_irqsave(&dev->list_lock, flags);
517 list_for_each_entry(list, &dev->list, node) {
518 int new_head = (list->head + 1) & (HIDRAW_BUFFER_SIZE - 1);
519
520 if (new_head == list->tail)
521 continue;
522
523 if (!(list->buffer[list->head].value = kmemdup(data, len, GFP_ATOMIC))) {
524 ret = -ENOMEM;
525 break;
526 }
527 list->buffer[list->head].len = len;
528 list->head = new_head;
529 kill_fasync(&list->fasync, SIGIO, POLL_IN);
530 }
531 spin_unlock_irqrestore(&dev->list_lock, flags);
532
533 wake_up_interruptible(&dev->wait);
534 return ret;
535}
536EXPORT_SYMBOL_GPL(hidraw_report_event);
537
538int hidraw_connect(struct hid_device *hid)
539{
540 int minor, result;
541 struct hidraw *dev;
542
543 /* we accept any HID device, all applications */
544
545 dev = kzalloc(sizeof(struct hidraw), GFP_KERNEL);
546 if (!dev)
547 return -ENOMEM;
548
549 result = -EINVAL;
550
551 down_write(&minors_rwsem);
552
553 for (minor = 0; minor < HIDRAW_MAX_DEVICES; minor++) {
554 if (hidraw_table[minor])
555 continue;
556 hidraw_table[minor] = dev;
557 result = 0;
558 break;
559 }
560
561 if (result) {
562 up_write(&minors_rwsem);
563 kfree(dev);
564 goto out;
565 }
566
567 dev->dev = device_create(hidraw_class, &hid->dev, MKDEV(hidraw_major, minor),
568 NULL, "%s%d", "hidraw", minor);
569
570 if (IS_ERR(dev->dev)) {
571 hidraw_table[minor] = NULL;
572 up_write(&minors_rwsem);
573 result = PTR_ERR(dev->dev);
574 kfree(dev);
575 goto out;
576 }
577
578 init_waitqueue_head(&dev->wait);
579 spin_lock_init(&dev->list_lock);
580 INIT_LIST_HEAD(&dev->list);
581
582 dev->hid = hid;
583 dev->minor = minor;
584
585 dev->exist = 1;
586 hid->hidraw = dev;
587
588 up_write(&minors_rwsem);
589out:
590 return result;
591
592}
593EXPORT_SYMBOL_GPL(hidraw_connect);
594
595void hidraw_disconnect(struct hid_device *hid)
596{
597 struct hidraw *hidraw = hid->hidraw;
598
599 down_write(&minors_rwsem);
600
601 drop_ref(hidraw, 1);
602
603 up_write(&minors_rwsem);
604}
605EXPORT_SYMBOL_GPL(hidraw_disconnect);
606
607int __init hidraw_init(void)
608{
609 int result;
610 dev_t dev_id;
611
612 result = alloc_chrdev_region(&dev_id, HIDRAW_FIRST_MINOR,
613 HIDRAW_MAX_DEVICES, "hidraw");
614 if (result < 0) {
615 pr_warn("can't get major number\n");
616 goto out;
617 }
618
619 hidraw_major = MAJOR(dev_id);
620
621 hidraw_class = class_create(THIS_MODULE, "hidraw");
622 if (IS_ERR(hidraw_class)) {
623 result = PTR_ERR(hidraw_class);
624 goto error_cdev;
625 }
626
627 cdev_init(&hidraw_cdev, &hidraw_ops);
628 result = cdev_add(&hidraw_cdev, dev_id, HIDRAW_MAX_DEVICES);
629 if (result < 0)
630 goto error_class;
631
632 pr_info("raw HID events driver (C) Jiri Kosina\n");
633out:
634 return result;
635
636error_class:
637 class_destroy(hidraw_class);
638error_cdev:
639 unregister_chrdev_region(dev_id, HIDRAW_MAX_DEVICES);
640 goto out;
641}
642
643void hidraw_exit(void)
644{
645 dev_t dev_id = MKDEV(hidraw_major, 0);
646
647 cdev_del(&hidraw_cdev);
648 class_destroy(hidraw_class);
649 unregister_chrdev_region(dev_id, HIDRAW_MAX_DEVICES);
650
651}