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22#include <linux/fs.h>
23#include <linux/module.h>
24#include <linux/errno.h>
25#include <linux/kernel.h>
26#include <linux/init.h>
27#include <linux/cdev.h>
28#include <linux/poll.h>
29#include <linux/device.h>
30#include <linux/major.h>
31#include <linux/hid.h>
32#include <linux/mutex.h>
33#include <linux/sched.h>
34#include <linux/smp_lock.h>
35
36#include <linux/hidraw.h>
37
38static int hidraw_major;
39static struct cdev hidraw_cdev;
40static struct class *hidraw_class;
41static struct hidraw *hidraw_table[HIDRAW_MAX_DEVICES];
42static DEFINE_MUTEX(minors_lock);
43
44static ssize_t hidraw_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos)
45{
46 struct hidraw_list *list = file->private_data;
47 int ret = 0, len;
48 char *report;
49 DECLARE_WAITQUEUE(wait, current);
50
51 mutex_lock(&list->read_mutex);
52
53 while (ret == 0) {
54 if (list->head == list->tail) {
55 add_wait_queue(&list->hidraw->wait, &wait);
56 set_current_state(TASK_INTERRUPTIBLE);
57
58 while (list->head == list->tail) {
59 if (file->f_flags & O_NONBLOCK) {
60 ret = -EAGAIN;
61 break;
62 }
63 if (signal_pending(current)) {
64 ret = -ERESTARTSYS;
65 break;
66 }
67 if (!list->hidraw->exist) {
68 ret = -EIO;
69 break;
70 }
71
72
73 mutex_unlock(&list->read_mutex);
74 schedule();
75 mutex_lock(&list->read_mutex);
76 set_current_state(TASK_INTERRUPTIBLE);
77 }
78
79 set_current_state(TASK_RUNNING);
80 remove_wait_queue(&list->hidraw->wait, &wait);
81 }
82
83 if (ret)
84 goto out;
85
86 report = list->buffer[list->tail].value;
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
105static ssize_t hidraw_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
106{
107 unsigned int minor = iminor(file->f_path.dentry->d_inode);
108
109 struct hid_device *dev = hidraw_table[minor]->hid;
110 __u8 *buf;
111 int ret = 0;
112
113 if (!dev->hid_output_raw_report)
114 return -ENODEV;
115
116 if (count > HID_MAX_BUFFER_SIZE) {
117 printk(KERN_WARNING "hidraw: pid %d passed too large report\n",
118 task_pid_nr(current));
119 return -EINVAL;
120 }
121
122 if (count < 2) {
123 printk(KERN_WARNING "hidraw: pid %d passed too short report\n",
124 task_pid_nr(current));
125 return -EINVAL;
126 }
127
128 buf = kmalloc(count * sizeof(__u8), GFP_KERNEL);
129 if (!buf)
130 return -ENOMEM;
131
132 if (copy_from_user(buf, buffer, count)) {
133 ret = -EFAULT;
134 goto out;
135 }
136
137 ret = dev->hid_output_raw_report(dev, buf, count);
138out:
139 kfree(buf);
140 return ret;
141}
142
143static unsigned int hidraw_poll(struct file *file, poll_table *wait)
144{
145 struct hidraw_list *list = file->private_data;
146
147 poll_wait(file, &list->hidraw->wait, wait);
148 if (list->head != list->tail)
149 return POLLIN | POLLRDNORM;
150 if (!list->hidraw->exist)
151 return POLLERR | POLLHUP;
152 return 0;
153}
154
155static int hidraw_open(struct inode *inode, struct file *file)
156{
157 unsigned int minor = iminor(inode);
158 struct hidraw *dev;
159 struct hidraw_list *list;
160 int err = 0;
161
162 if (!(list = kzalloc(sizeof(struct hidraw_list), GFP_KERNEL))) {
163 err = -ENOMEM;
164 goto out;
165 }
166
167 lock_kernel();
168 mutex_lock(&minors_lock);
169 if (!hidraw_table[minor]) {
170 printk(KERN_EMERG "hidraw device with minor %d doesn't exist\n",
171 minor);
172 kfree(list);
173 err = -ENODEV;
174 goto out_unlock;
175 }
176
177 list->hidraw = hidraw_table[minor];
178 mutex_init(&list->read_mutex);
179 list_add_tail(&list->node, &hidraw_table[minor]->list);
180 file->private_data = list;
181
182 dev = hidraw_table[minor];
183 if (!dev->open++) {
184 if (dev->hid->ll_driver->power) {
185 err = dev->hid->ll_driver->power(dev->hid, PM_HINT_FULLON);
186 if (err < 0)
187 goto out_unlock;
188 }
189 err = dev->hid->ll_driver->open(dev->hid);
190 if (err < 0) {
191 if (dev->hid->ll_driver->power)
192 dev->hid->ll_driver->power(dev->hid, PM_HINT_NORMAL);
193 dev->open--;
194 }
195 }
196
197out_unlock:
198 mutex_unlock(&minors_lock);
199 unlock_kernel();
200out:
201 return err;
202
203}
204
205static int hidraw_release(struct inode * inode, struct file * file)
206{
207 unsigned int minor = iminor(inode);
208 struct hidraw *dev;
209 struct hidraw_list *list = file->private_data;
210
211 if (!hidraw_table[minor]) {
212 printk(KERN_EMERG "hidraw device with minor %d doesn't exist\n",
213 minor);
214 return -ENODEV;
215 }
216
217 list_del(&list->node);
218 dev = hidraw_table[minor];
219 if (!--dev->open) {
220 if (list->hidraw->exist) {
221 if (dev->hid->ll_driver->power)
222 dev->hid->ll_driver->power(dev->hid, PM_HINT_NORMAL);
223 dev->hid->ll_driver->close(dev->hid);
224 } else {
225 kfree(list->hidraw);
226 }
227 }
228
229 kfree(list);
230
231 return 0;
232}
233
234static long hidraw_ioctl(struct file *file, unsigned int cmd,
235 unsigned long arg)
236{
237 struct inode *inode = file->f_path.dentry->d_inode;
238 unsigned int minor = iminor(inode);
239 long ret = 0;
240
241 struct hidraw *dev = hidraw_table[minor];
242 void __user *user_arg = (void __user*) arg;
243
244 lock_kernel();
245 switch (cmd) {
246 case HIDIOCGRDESCSIZE:
247 if (put_user(dev->hid->rsize, (int __user *)arg))
248 ret = -EFAULT;
249 break;
250
251 case HIDIOCGRDESC:
252 {
253 __u32 len;
254
255 if (get_user(len, (int __user *)arg))
256 ret = -EFAULT;
257 else if (len > HID_MAX_DESCRIPTOR_SIZE - 1)
258 ret = -EINVAL;
259 else if (copy_to_user(user_arg + offsetof(
260 struct hidraw_report_descriptor,
261 value[0]),
262 dev->hid->rdesc,
263 min(dev->hid->rsize, len)))
264 ret = -EFAULT;
265 break;
266 }
267 case HIDIOCGRAWINFO:
268 {
269 struct hidraw_devinfo dinfo;
270
271 dinfo.bustype = dev->hid->bus;
272 dinfo.vendor = dev->hid->vendor;
273 dinfo.product = dev->hid->product;
274 if (copy_to_user(user_arg, &dinfo, sizeof(dinfo)))
275 ret = -EFAULT;
276 break;
277 }
278 default:
279 {
280 struct hid_device *hid = dev->hid;
281 if (_IOC_TYPE(cmd) != 'H' || _IOC_DIR(cmd) != _IOC_READ) {
282 ret = -EINVAL;
283 break;
284 }
285
286 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGRAWNAME(0))) {
287 int len;
288 if (!hid->name) {
289 ret = 0;
290 break;
291 }
292 len = strlen(hid->name) + 1;
293 if (len > _IOC_SIZE(cmd))
294 len = _IOC_SIZE(cmd);
295 ret = copy_to_user(user_arg, hid->name, len) ?
296 -EFAULT : len;
297 break;
298 }
299
300 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGRAWPHYS(0))) {
301 int len;
302 if (!hid->phys) {
303 ret = 0;
304 break;
305 }
306 len = strlen(hid->phys) + 1;
307 if (len > _IOC_SIZE(cmd))
308 len = _IOC_SIZE(cmd);
309 ret = copy_to_user(user_arg, hid->phys, len) ?
310 -EFAULT : len;
311 break;
312 }
313 }
314
315 ret = -ENOTTY;
316 }
317 unlock_kernel();
318 return ret;
319}
320
321static const struct file_operations hidraw_ops = {
322 .owner = THIS_MODULE,
323 .read = hidraw_read,
324 .write = hidraw_write,
325 .poll = hidraw_poll,
326 .open = hidraw_open,
327 .release = hidraw_release,
328 .unlocked_ioctl = hidraw_ioctl,
329};
330
331void hidraw_report_event(struct hid_device *hid, u8 *data, int len)
332{
333 struct hidraw *dev = hid->hidraw;
334 struct hidraw_list *list;
335
336 list_for_each_entry(list, &dev->list, node) {
337 list->buffer[list->head].value = kmemdup(data, len, GFP_ATOMIC);
338 list->buffer[list->head].len = len;
339 list->head = (list->head + 1) & (HIDRAW_BUFFER_SIZE - 1);
340 kill_fasync(&list->fasync, SIGIO, POLL_IN);
341 }
342
343 wake_up_interruptible(&dev->wait);
344}
345EXPORT_SYMBOL_GPL(hidraw_report_event);
346
347int hidraw_connect(struct hid_device *hid)
348{
349 int minor, result;
350 struct hidraw *dev;
351
352
353
354 dev = kzalloc(sizeof(struct hidraw), GFP_KERNEL);
355 if (!dev)
356 return -ENOMEM;
357
358 result = -EINVAL;
359
360 mutex_lock(&minors_lock);
361
362 for (minor = 0; minor < HIDRAW_MAX_DEVICES; minor++) {
363 if (hidraw_table[minor])
364 continue;
365 hidraw_table[minor] = dev;
366 result = 0;
367 break;
368 }
369
370 if (result) {
371 mutex_unlock(&minors_lock);
372 kfree(dev);
373 goto out;
374 }
375
376 dev->dev = device_create(hidraw_class, &hid->dev, MKDEV(hidraw_major, minor),
377 NULL, "%s%d", "hidraw", minor);
378
379 if (IS_ERR(dev->dev)) {
380 hidraw_table[minor] = NULL;
381 mutex_unlock(&minors_lock);
382 result = PTR_ERR(dev->dev);
383 kfree(dev);
384 goto out;
385 }
386
387 mutex_unlock(&minors_lock);
388 init_waitqueue_head(&dev->wait);
389 INIT_LIST_HEAD(&dev->list);
390
391 dev->hid = hid;
392 dev->minor = minor;
393
394 dev->exist = 1;
395 hid->hidraw = dev;
396
397out:
398 return result;
399
400}
401EXPORT_SYMBOL_GPL(hidraw_connect);
402
403void hidraw_disconnect(struct hid_device *hid)
404{
405 struct hidraw *hidraw = hid->hidraw;
406
407 hidraw->exist = 0;
408
409 mutex_lock(&minors_lock);
410 hidraw_table[hidraw->minor] = NULL;
411 mutex_unlock(&minors_lock);
412
413 device_destroy(hidraw_class, MKDEV(hidraw_major, hidraw->minor));
414
415 if (hidraw->open) {
416 hid->ll_driver->close(hid);
417 wake_up_interruptible(&hidraw->wait);
418 } else {
419 kfree(hidraw);
420 }
421}
422EXPORT_SYMBOL_GPL(hidraw_disconnect);
423
424int __init hidraw_init(void)
425{
426 int result;
427 dev_t dev_id;
428
429 result = alloc_chrdev_region(&dev_id, HIDRAW_FIRST_MINOR,
430 HIDRAW_MAX_DEVICES, "hidraw");
431
432 hidraw_major = MAJOR(dev_id);
433
434 if (result < 0) {
435 printk(KERN_WARNING "hidraw: can't get major number\n");
436 result = 0;
437 goto out;
438 }
439
440 hidraw_class = class_create(THIS_MODULE, "hidraw");
441 if (IS_ERR(hidraw_class)) {
442 result = PTR_ERR(hidraw_class);
443 unregister_chrdev(hidraw_major, "hidraw");
444 goto out;
445 }
446
447 cdev_init(&hidraw_cdev, &hidraw_ops);
448 cdev_add(&hidraw_cdev, dev_id, HIDRAW_MAX_DEVICES);
449out:
450 return result;
451}
452
453void hidraw_exit(void)
454{
455 dev_t dev_id = MKDEV(hidraw_major, 0);
456
457 cdev_del(&hidraw_cdev);
458 class_destroy(hidraw_class);
459 unregister_chrdev_region(dev_id, HIDRAW_MAX_DEVICES);
460
461}
462
