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v3.1
  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}
v4.17
  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) 2007-2014 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/signal.h>
 37#include <linux/string.h>
 38
 39#include <linux/hidraw.h>
 40
 41static int hidraw_major;
 42static struct cdev hidraw_cdev;
 43static struct class *hidraw_class;
 44static struct hidraw *hidraw_table[HIDRAW_MAX_DEVICES];
 45static DEFINE_MUTEX(minors_lock);
 46
 47static ssize_t hidraw_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos)
 48{
 49	struct hidraw_list *list = file->private_data;
 50	int ret = 0, len;
 51	DECLARE_WAITQUEUE(wait, current);
 52
 53	mutex_lock(&list->read_mutex);
 54
 55	while (ret == 0) {
 56		if (list->head == list->tail) {
 57			add_wait_queue(&list->hidraw->wait, &wait);
 58			set_current_state(TASK_INTERRUPTIBLE);
 59
 60			while (list->head == list->tail) {
 
 
 
 
 61				if (signal_pending(current)) {
 62					ret = -ERESTARTSYS;
 63					break;
 64				}
 65				if (!list->hidraw->exist) {
 66					ret = -EIO;
 67					break;
 68				}
 69				if (file->f_flags & O_NONBLOCK) {
 70					ret = -EAGAIN;
 71					break;
 72				}
 73
 74				/* allow O_NONBLOCK to work well from other threads */
 75				mutex_unlock(&list->read_mutex);
 76				schedule();
 77				mutex_lock(&list->read_mutex);
 78				set_current_state(TASK_INTERRUPTIBLE);
 79			}
 80
 81			set_current_state(TASK_RUNNING);
 82			remove_wait_queue(&list->hidraw->wait, &wait);
 83		}
 84
 85		if (ret)
 86			goto out;
 87
 88		len = list->buffer[list->tail].len > count ?
 89			count : list->buffer[list->tail].len;
 90
 91		if (list->buffer[list->tail].value) {
 92			if (copy_to_user(buffer, list->buffer[list->tail].value, len)) {
 93				ret = -EFAULT;
 94				goto out;
 95			}
 96			ret = len;
 97		}
 
 98
 99		kfree(list->buffer[list->tail].value);
100		list->buffer[list->tail].value = NULL;
101		list->tail = (list->tail + 1) & (HIDRAW_BUFFER_SIZE - 1);
102	}
103out:
104	mutex_unlock(&list->read_mutex);
105	return ret;
106}
107
108/*
109 * The first byte of the report buffer is expected to be a report number.
110 *
111 * This function is to be called with the minors_lock mutex held.
112 */
113static ssize_t hidraw_send_report(struct file *file, const char __user *buffer, size_t count, unsigned char report_type)
114{
115	unsigned int minor = iminor(file_inode(file));
116	struct hid_device *dev;
117	__u8 *buf;
118	int ret = 0;
119
120	if (!hidraw_table[minor] || !hidraw_table[minor]->exist) {
121		ret = -ENODEV;
122		goto out;
123	}
124
125	dev = hidraw_table[minor]->hid;
126
 
 
 
 
 
127	if (count > HID_MAX_BUFFER_SIZE) {
128		hid_warn(dev, "pid %d passed too large report\n",
129			 task_pid_nr(current));
130		ret = -EINVAL;
131		goto out;
132	}
133
134	if (count < 2) {
135		hid_warn(dev, "pid %d passed too short report\n",
136			 task_pid_nr(current));
137		ret = -EINVAL;
138		goto out;
139	}
140
141	buf = memdup_user(buffer, count);
142	if (IS_ERR(buf)) {
143		ret = PTR_ERR(buf);
144		goto out;
145	}
146
147	if ((report_type == HID_OUTPUT_REPORT) &&
148	    !(dev->quirks & HID_QUIRK_NO_OUTPUT_REPORTS_ON_INTR_EP)) {
149		ret = hid_hw_output_report(dev, buf, count);
150		/*
151		 * compatibility with old implementation of USB-HID and I2C-HID:
152		 * if the device does not support receiving output reports,
153		 * on an interrupt endpoint, fallback to SET_REPORT HID command.
154		 */
155		if (ret != -ENOSYS)
156			goto out_free;
157	}
158
159	ret = hid_hw_raw_request(dev, buf[0], buf, count, report_type,
160				HID_REQ_SET_REPORT);
161
162out_free:
163	kfree(buf);
164out:
165	return ret;
166}
167
 
168static ssize_t hidraw_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
169{
170	ssize_t ret;
171	mutex_lock(&minors_lock);
172	ret = hidraw_send_report(file, buffer, count, HID_OUTPUT_REPORT);
173	mutex_unlock(&minors_lock);
174	return ret;
175}
176
177
178/*
179 * This function performs a Get_Report transfer over the control endpoint
180 * per section 7.2.1 of the HID specification, version 1.1.  The first byte
181 * of buffer is the report number to request, or 0x0 if the defice does not
182 * use numbered reports. The report_type parameter can be HID_FEATURE_REPORT
183 * or HID_INPUT_REPORT.
184 *
185 * This function is to be called with the minors_lock mutex held.
186 */
187static ssize_t hidraw_get_report(struct file *file, char __user *buffer, size_t count, unsigned char report_type)
188{
189	unsigned int minor = iminor(file_inode(file));
190	struct hid_device *dev;
191	__u8 *buf;
192	int ret = 0, len;
193	unsigned char report_number;
194
195	if (!hidraw_table[minor] || !hidraw_table[minor]->exist) {
196		ret = -ENODEV;
197		goto out;
198	}
199
200	dev = hidraw_table[minor]->hid;
201
202	if (!dev->ll_driver->raw_request) {
203		ret = -ENODEV;
204		goto out;
205	}
206
207	if (count > HID_MAX_BUFFER_SIZE) {
208		printk(KERN_WARNING "hidraw: pid %d passed too large report\n",
209				task_pid_nr(current));
210		ret = -EINVAL;
211		goto out;
212	}
213
214	if (count < 2) {
215		printk(KERN_WARNING "hidraw: pid %d passed too short report\n",
216				task_pid_nr(current));
217		ret = -EINVAL;
218		goto out;
219	}
220
221	buf = kmalloc(count * sizeof(__u8), GFP_KERNEL);
222	if (!buf) {
223		ret = -ENOMEM;
224		goto out;
225	}
226
227	/*
228	 * Read the first byte from the user. This is the report number,
229	 * which is passed to hid_hw_raw_request().
230	 */
231	if (copy_from_user(&report_number, buffer, 1)) {
232		ret = -EFAULT;
233		goto out_free;
234	}
235
236	ret = hid_hw_raw_request(dev, report_number, buf, count, report_type,
237				 HID_REQ_GET_REPORT);
238
239	if (ret < 0)
240		goto out_free;
241
242	len = (ret < count) ? ret : count;
243
244	if (copy_to_user(buffer, buf, len)) {
245		ret = -EFAULT;
246		goto out_free;
247	}
248
249	ret = len;
250
251out_free:
252	kfree(buf);
253out:
254	return ret;
255}
256
257static __poll_t hidraw_poll(struct file *file, poll_table *wait)
258{
259	struct hidraw_list *list = file->private_data;
260
261	poll_wait(file, &list->hidraw->wait, wait);
262	if (list->head != list->tail)
263		return EPOLLIN | EPOLLRDNORM;
264	if (!list->hidraw->exist)
265		return EPOLLERR | EPOLLHUP;
266	return 0;
267}
268
269static int hidraw_open(struct inode *inode, struct file *file)
270{
271	unsigned int minor = iminor(inode);
272	struct hidraw *dev;
273	struct hidraw_list *list;
274	unsigned long flags;
275	int err = 0;
276
277	if (!(list = kzalloc(sizeof(struct hidraw_list), GFP_KERNEL))) {
278		err = -ENOMEM;
279		goto out;
280	}
281
282	mutex_lock(&minors_lock);
283	if (!hidraw_table[minor] || !hidraw_table[minor]->exist) {
 
284		err = -ENODEV;
285		goto out_unlock;
286	}
287
 
 
 
 
 
288	dev = hidraw_table[minor];
289	if (!dev->open++) {
290		err = hid_hw_power(dev->hid, PM_HINT_FULLON);
291		if (err < 0) {
292			dev->open--;
293			goto out_unlock;
294		}
295
296		err = hid_hw_open(dev->hid);
297		if (err < 0) {
298			hid_hw_power(dev->hid, PM_HINT_NORMAL);
299			dev->open--;
300			goto out_unlock;
301		}
302	}
303
304	list->hidraw = hidraw_table[minor];
305	mutex_init(&list->read_mutex);
306	spin_lock_irqsave(&hidraw_table[minor]->list_lock, flags);
307	list_add_tail(&list->node, &hidraw_table[minor]->list);
308	spin_unlock_irqrestore(&hidraw_table[minor]->list_lock, flags);
309	file->private_data = list;
310out_unlock:
311	mutex_unlock(&minors_lock);
312out:
313	if (err < 0)
314		kfree(list);
315	return err;
316
317}
318
319static int hidraw_fasync(int fd, struct file *file, int on)
320{
321	struct hidraw_list *list = file->private_data;
322
323	return fasync_helper(fd, file, on, &list->fasync);
324}
325
326static void drop_ref(struct hidraw *hidraw, int exists_bit)
327{
328	if (exists_bit) {
329		hidraw->exist = 0;
330		if (hidraw->open) {
331			hid_hw_close(hidraw->hid);
332			wake_up_interruptible(&hidraw->wait);
333		}
334		device_destroy(hidraw_class,
335			       MKDEV(hidraw_major, hidraw->minor));
336	} else {
337		--hidraw->open;
338	}
339	if (!hidraw->open) {
340		if (!hidraw->exist) {
341			hidraw_table[hidraw->minor] = NULL;
342			kfree(hidraw);
343		} else {
344			/* close device for last reader */
345			hid_hw_close(hidraw->hid);
346			hid_hw_power(hidraw->hid, PM_HINT_NORMAL);
347		}
348	}
349}
350
351static int hidraw_release(struct inode * inode, struct file * file)
352{
353	unsigned int minor = iminor(inode);
 
354	struct hidraw_list *list = file->private_data;
355	unsigned long flags;
356
357	mutex_lock(&minors_lock);
 
 
 
 
358
359	spin_lock_irqsave(&hidraw_table[minor]->list_lock, flags);
360	list_del(&list->node);
361	spin_unlock_irqrestore(&hidraw_table[minor]->list_lock, flags);
 
 
 
 
 
 
 
 
362	kfree(list);
 
 
 
363
364	drop_ref(hidraw_table[minor], 0);
365
366	mutex_unlock(&minors_lock);
367	return 0;
368}
369
370static long hidraw_ioctl(struct file *file, unsigned int cmd,
371							unsigned long arg)
372{
373	struct inode *inode = file_inode(file);
374	unsigned int minor = iminor(inode);
375	long ret = 0;
376	struct hidraw *dev;
377	void __user *user_arg = (void __user*) arg;
378
379	mutex_lock(&minors_lock);
380	dev = hidraw_table[minor];
381	if (!dev) {
382		ret = -ENODEV;
383		goto out;
384	}
385
386	switch (cmd) {
387		case HIDIOCGRDESCSIZE:
388			if (put_user(dev->hid->rsize, (int __user *)arg))
389				ret = -EFAULT;
390			break;
391
392		case HIDIOCGRDESC:
393			{
394				__u32 len;
395
396				if (get_user(len, (int __user *)arg))
397					ret = -EFAULT;
398				else if (len > HID_MAX_DESCRIPTOR_SIZE - 1)
399					ret = -EINVAL;
400				else if (copy_to_user(user_arg + offsetof(
401					struct hidraw_report_descriptor,
402					value[0]),
403					dev->hid->rdesc,
404					min(dev->hid->rsize, len)))
405					ret = -EFAULT;
406				break;
407			}
408		case HIDIOCGRAWINFO:
409			{
410				struct hidraw_devinfo dinfo;
411
412				dinfo.bustype = dev->hid->bus;
413				dinfo.vendor = dev->hid->vendor;
414				dinfo.product = dev->hid->product;
415				if (copy_to_user(user_arg, &dinfo, sizeof(dinfo)))
416					ret = -EFAULT;
417				break;
418			}
419		default:
420			{
421				struct hid_device *hid = dev->hid;
422				if (_IOC_TYPE(cmd) != 'H') {
423					ret = -EINVAL;
424					break;
425				}
426
427				if (_IOC_NR(cmd) == _IOC_NR(HIDIOCSFEATURE(0))) {
428					int len = _IOC_SIZE(cmd);
429					ret = hidraw_send_report(file, user_arg, len, HID_FEATURE_REPORT);
430					break;
431				}
432				if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGFEATURE(0))) {
433					int len = _IOC_SIZE(cmd);
434					ret = hidraw_get_report(file, user_arg, len, HID_FEATURE_REPORT);
435					break;
436				}
437
438				/* Begin Read-only ioctls. */
439				if (_IOC_DIR(cmd) != _IOC_READ) {
440					ret = -EINVAL;
441					break;
442				}
443
444				if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGRAWNAME(0))) {
445					int len = strlen(hid->name) + 1;
446					if (len > _IOC_SIZE(cmd))
447						len = _IOC_SIZE(cmd);
448					ret = copy_to_user(user_arg, hid->name, len) ?
449						-EFAULT : len;
450					break;
451				}
452
453				if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGRAWPHYS(0))) {
454					int len = strlen(hid->phys) + 1;
455					if (len > _IOC_SIZE(cmd))
456						len = _IOC_SIZE(cmd);
457					ret = copy_to_user(user_arg, hid->phys, len) ?
458						-EFAULT : len;
459					break;
460				}
461			}
462
463		ret = -ENOTTY;
464	}
465out:
466	mutex_unlock(&minors_lock);
467	return ret;
468}
469
470static const struct file_operations hidraw_ops = {
471	.owner =        THIS_MODULE,
472	.read =         hidraw_read,
473	.write =        hidraw_write,
474	.poll =         hidraw_poll,
475	.open =         hidraw_open,
476	.release =      hidraw_release,
477	.unlocked_ioctl = hidraw_ioctl,
478	.fasync =	hidraw_fasync,
479#ifdef CONFIG_COMPAT
480	.compat_ioctl   = hidraw_ioctl,
481#endif
482	.llseek =	noop_llseek,
483};
484
485int hidraw_report_event(struct hid_device *hid, u8 *data, int len)
486{
487	struct hidraw *dev = hid->hidraw;
488	struct hidraw_list *list;
489	int ret = 0;
490	unsigned long flags;
491
492	spin_lock_irqsave(&dev->list_lock, flags);
493	list_for_each_entry(list, &dev->list, node) {
494		int new_head = (list->head + 1) & (HIDRAW_BUFFER_SIZE - 1);
495
496		if (new_head == list->tail)
497			continue;
498
499		if (!(list->buffer[list->head].value = kmemdup(data, len, GFP_ATOMIC))) {
500			ret = -ENOMEM;
501			break;
502		}
503		list->buffer[list->head].len = len;
504		list->head = new_head;
505		kill_fasync(&list->fasync, SIGIO, POLL_IN);
506	}
507	spin_unlock_irqrestore(&dev->list_lock, flags);
508
509	wake_up_interruptible(&dev->wait);
510	return ret;
511}
512EXPORT_SYMBOL_GPL(hidraw_report_event);
513
514int hidraw_connect(struct hid_device *hid)
515{
516	int minor, result;
517	struct hidraw *dev;
518
519	/* we accept any HID device, all applications */
520
521	dev = kzalloc(sizeof(struct hidraw), GFP_KERNEL);
522	if (!dev)
523		return -ENOMEM;
524
525	result = -EINVAL;
526
527	mutex_lock(&minors_lock);
528
529	for (minor = 0; minor < HIDRAW_MAX_DEVICES; minor++) {
530		if (hidraw_table[minor])
531			continue;
532		hidraw_table[minor] = dev;
533		result = 0;
534		break;
535	}
536
537	if (result) {
538		mutex_unlock(&minors_lock);
539		kfree(dev);
540		goto out;
541	}
542
543	dev->dev = device_create(hidraw_class, &hid->dev, MKDEV(hidraw_major, minor),
544				 NULL, "%s%d", "hidraw", minor);
545
546	if (IS_ERR(dev->dev)) {
547		hidraw_table[minor] = NULL;
548		mutex_unlock(&minors_lock);
549		result = PTR_ERR(dev->dev);
550		kfree(dev);
551		goto out;
552	}
553
 
554	init_waitqueue_head(&dev->wait);
555	spin_lock_init(&dev->list_lock);
556	INIT_LIST_HEAD(&dev->list);
557
558	dev->hid = hid;
559	dev->minor = minor;
560
561	dev->exist = 1;
562	hid->hidraw = dev;
563
564	mutex_unlock(&minors_lock);
565out:
566	return result;
567
568}
569EXPORT_SYMBOL_GPL(hidraw_connect);
570
571void hidraw_disconnect(struct hid_device *hid)
572{
573	struct hidraw *hidraw = hid->hidraw;
574
575	mutex_lock(&minors_lock);
576
577	drop_ref(hidraw, 1);
578
 
 
579	mutex_unlock(&minors_lock);
 
 
 
 
 
 
 
580}
581EXPORT_SYMBOL_GPL(hidraw_disconnect);
582
583int __init hidraw_init(void)
584{
585	int result;
586	dev_t dev_id;
587
588	result = alloc_chrdev_region(&dev_id, HIDRAW_FIRST_MINOR,
589			HIDRAW_MAX_DEVICES, "hidraw");
 
 
 
590	if (result < 0) {
591		pr_warn("can't get major number\n");
 
592		goto out;
593	}
594
595	hidraw_major = MAJOR(dev_id);
596
597	hidraw_class = class_create(THIS_MODULE, "hidraw");
598	if (IS_ERR(hidraw_class)) {
599		result = PTR_ERR(hidraw_class);
600		goto error_cdev;
 
601	}
602
603        cdev_init(&hidraw_cdev, &hidraw_ops);
604	result = cdev_add(&hidraw_cdev, dev_id, HIDRAW_MAX_DEVICES);
605	if (result < 0)
606		goto error_class;
607
608	printk(KERN_INFO "hidraw: raw HID events driver (C) Jiri Kosina\n");
609out:
610	return result;
611
612error_class:
613	class_destroy(hidraw_class);
614error_cdev:
615	unregister_chrdev_region(dev_id, HIDRAW_MAX_DEVICES);
616	goto out;
617}
618
619void hidraw_exit(void)
620{
621	dev_t dev_id = MKDEV(hidraw_major, 0);
622
623	cdev_del(&hidraw_cdev);
624	class_destroy(hidraw_class);
625	unregister_chrdev_region(dev_id, HIDRAW_MAX_DEVICES);
626
627}