1/*
2 *  Copyright (c) 2001 Paul Stewart
3 *  Copyright (c) 2001 Vojtech Pavlik
4 *
5 *  HID char devices, giving access to raw HID device events.
6 *
7 */
8
9/*
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18 * GNU General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23 *
24 * Should you need to contact me, the author, you can do so either by
25 * e-mail - mail your message to Paul Stewart <stewart@wetlogic.net>
26 */
27
28#include <linux/poll.h>
29#include <linux/slab.h>
30#include <linux/module.h>
31#include <linux/init.h>
32#include <linux/smp_lock.h>
33#include <linux/input.h>
34#include <linux/usb.h>
35#include <linux/hid.h>
36#include <linux/hiddev.h>
37#include "usbhid.h"
38
39#ifdef CONFIG_USB_DYNAMIC_MINORS
40#define HIDDEV_MINOR_BASE	0
41#define HIDDEV_MINORS		256
42#else
43#define HIDDEV_MINOR_BASE	96
44#define HIDDEV_MINORS		16
45#endif
46#define HIDDEV_BUFFER_SIZE	64
47
48struct hiddev {
49	int exist;
50	int open;
51	wait_queue_head_t wait;
52	struct hid_device *hid;
53	struct list_head list;
54	spinlock_t list_lock;
55};
56
57struct hiddev_list {
58	struct hiddev_usage_ref buffer[HIDDEV_BUFFER_SIZE];
59	int head;
60	int tail;
61	unsigned flags;
62	struct fasync_struct *fasync;
63	struct hiddev *hiddev;
64	struct list_head node;
65};
66
67static struct hiddev *hiddev_table[HIDDEV_MINORS];
68
69/*
70 * Find a report, given the report's type and ID.  The ID can be specified
71 * indirectly by REPORT_ID_FIRST (which returns the first report of the given
72 * type) or by (REPORT_ID_NEXT | old_id), which returns the next report of the
73 * given type which follows old_id.
74 */
75static struct hid_report *
76hiddev_lookup_report(struct hid_device *hid, struct hiddev_report_info *rinfo)
77{
78	unsigned int flags = rinfo->report_id & ~HID_REPORT_ID_MASK;
79	unsigned int rid = rinfo->report_id & HID_REPORT_ID_MASK;
80	struct hid_report_enum *report_enum;
81	struct hid_report *report;
82	struct list_head *list;
83
84	if (rinfo->report_type < HID_REPORT_TYPE_MIN ||
85	    rinfo->report_type > HID_REPORT_TYPE_MAX)
86		return NULL;
87
88	report_enum = hid->report_enum +
89		(rinfo->report_type - HID_REPORT_TYPE_MIN);
90
91	switch (flags) {
92	case 0: /* Nothing to do -- report_id is already set correctly */
93		break;
94
95	case HID_REPORT_ID_FIRST:
96		if (list_empty(&report_enum->report_list))
97			return NULL;
98
99		list = report_enum->report_list.next;
100		report = list_entry(list, struct hid_report, list);
101		rinfo->report_id = report->id;
102		break;
103
104	case HID_REPORT_ID_NEXT:
105		report = report_enum->report_id_hash[rid];
106		if (!report)
107			return NULL;
108
109		list = report->list.next;
110		if (list == &report_enum->report_list)
111			return NULL;
112
113		report = list_entry(list, struct hid_report, list);
114		rinfo->report_id = report->id;
115		break;
116
117	default:
118		return NULL;
119	}
120
121	return report_enum->report_id_hash[rinfo->report_id];
122}
123
124/*
125 * Perform an exhaustive search of the report table for a usage, given its
126 * type and usage id.
127 */
128static struct hid_field *
129hiddev_lookup_usage(struct hid_device *hid, struct hiddev_usage_ref *uref)
130{
131	int i, j;
132	struct hid_report *report;
133	struct hid_report_enum *report_enum;
134	struct hid_field *field;
135
136	if (uref->report_type < HID_REPORT_TYPE_MIN ||
137	    uref->report_type > HID_REPORT_TYPE_MAX)
138		return NULL;
139
140	report_enum = hid->report_enum +
141		(uref->report_type - HID_REPORT_TYPE_MIN);
142
143	list_for_each_entry(report, &report_enum->report_list, list) {
144		for (i = 0; i < report->maxfield; i++) {
145			field = report->field[i];
146			for (j = 0; j < field->maxusage; j++) {
147				if (field->usage[j].hid == uref->usage_code) {
148					uref->report_id = report->id;
149					uref->field_index = i;
150					uref->usage_index = j;
151					return field;
152				}
153			}
154		}
155	}
156
157	return NULL;
158}
159
160static void hiddev_send_event(struct hid_device *hid,
161			      struct hiddev_usage_ref *uref)
162{
163	struct hiddev *hiddev = hid->hiddev;
164	struct hiddev_list *list;
165	unsigned long flags;
166
167	spin_lock_irqsave(&hiddev->list_lock, flags);
168	list_for_each_entry(list, &hiddev->list, node) {
169		if (uref->field_index != HID_FIELD_INDEX_NONE ||
170		    (list->flags & HIDDEV_FLAG_REPORT) != 0) {
171			list->buffer[list->head] = *uref;
172			list->head = (list->head + 1) &
173				(HIDDEV_BUFFER_SIZE - 1);
174			kill_fasync(&list->fasync, SIGIO, POLL_IN);
175		}
176	}
177	spin_unlock_irqrestore(&hiddev->list_lock, flags);
178
179	wake_up_interruptible(&hiddev->wait);
180}
181
182/*
183 * This is where hid.c calls into hiddev to pass an event that occurred over
184 * the interrupt pipe
185 */
186void hiddev_hid_event(struct hid_device *hid, struct hid_field *field,
187		      struct hid_usage *usage, __s32 value)
188{
189	unsigned type = field->report_type;
190	struct hiddev_usage_ref uref;
191
192	uref.report_type =
193	  (type == HID_INPUT_REPORT) ? HID_REPORT_TYPE_INPUT :
194	  ((type == HID_OUTPUT_REPORT) ? HID_REPORT_TYPE_OUTPUT :
195	   ((type == HID_FEATURE_REPORT) ? HID_REPORT_TYPE_FEATURE : 0));
196	uref.report_id = field->report->id;
197	uref.field_index = field->index;
198	uref.usage_index = (usage - field->usage);
199	uref.usage_code = usage->hid;
200	uref.value = value;
201
202	hiddev_send_event(hid, &uref);
203}
204EXPORT_SYMBOL_GPL(hiddev_hid_event);
205
206void hiddev_report_event(struct hid_device *hid, struct hid_report *report)
207{
208	unsigned type = report->type;
209	struct hiddev_usage_ref uref;
210
211	memset(&uref, 0, sizeof(uref));
212	uref.report_type =
213	  (type == HID_INPUT_REPORT) ? HID_REPORT_TYPE_INPUT :
214	  ((type == HID_OUTPUT_REPORT) ? HID_REPORT_TYPE_OUTPUT :
215	   ((type == HID_FEATURE_REPORT) ? HID_REPORT_TYPE_FEATURE : 0));
216	uref.report_id = report->id;
217	uref.field_index = HID_FIELD_INDEX_NONE;
218
219	hiddev_send_event(hid, &uref);
220}
221
222/*
223 * fasync file op
224 */
225static int hiddev_fasync(int fd, struct file *file, int on)
226{
227	int retval;
228	struct hiddev_list *list = file->private_data;
229
230	retval = fasync_helper(fd, file, on, &list->fasync);
231
232	return retval < 0 ? retval : 0;
233}
234
235
236/*
237 * release file op
238 */
239static int hiddev_release(struct inode * inode, struct file * file)
240{
241	struct hiddev_list *list = file->private_data;
242	unsigned long flags;
243
244	hiddev_fasync(-1, file, 0);
245
246	spin_lock_irqsave(&list->hiddev->list_lock, flags);
247	list_del(&list->node);
248	spin_unlock_irqrestore(&list->hiddev->list_lock, flags);
249
250	if (!--list->hiddev->open) {
251		if (list->hiddev->exist)
252			usbhid_close(list->hiddev->hid);
253		else
254			kfree(list->hiddev);
255	}
256
257	kfree(list);
258
259	return 0;
260}
261
262/*
263 * open file op
264 */
265static int hiddev_open(struct inode *inode, struct file *file)
266{
267	struct hiddev_list *list;
268	unsigned long flags;
269
270	int i = iminor(inode) - HIDDEV_MINOR_BASE;
271
272	if (i >= HIDDEV_MINORS || !hiddev_table[i])
273		return -ENODEV;
274
275	if (!(list = kzalloc(sizeof(struct hiddev_list), GFP_KERNEL)))
276		return -ENOMEM;
277
278	list->hiddev = hiddev_table[i];
279
280	spin_lock_irqsave(&list->hiddev->list_lock, flags);
281	list_add_tail(&list->node, &hiddev_table[i]->list);
282	spin_unlock_irqrestore(&list->hiddev->list_lock, flags);
283
284	file->private_data = list;
285
286	if (!list->hiddev->open++)
287		if (list->hiddev->exist)
288			usbhid_open(hiddev_table[i]->hid);
289
290	return 0;
291}
292
293/*
294 * "write" file op
295 */
296static ssize_t hiddev_write(struct file * file, const char __user * buffer, size_t count, loff_t *ppos)
297{
298	return -EINVAL;
299}
300
301/*
302 * "read" file op
303 */
304static ssize_t hiddev_read(struct file * file, char __user * buffer, size_t count, loff_t *ppos)
305{
306	DECLARE_WAITQUEUE(wait, current);
307	struct hiddev_list *list = file->private_data;
308	int event_size;
309	int retval = 0;
310
311	event_size = ((list->flags & HIDDEV_FLAG_UREF) != 0) ?
312		sizeof(struct hiddev_usage_ref) : sizeof(struct hiddev_event);
313
314	if (count < event_size)
315		return 0;
316
317	while (retval == 0) {
318		if (list->head == list->tail) {
319			add_wait_queue(&list->hiddev->wait, &wait);
320			set_current_state(TASK_INTERRUPTIBLE);
321
322			while (list->head == list->tail) {
323				if (file->f_flags & O_NONBLOCK) {
324					retval = -EAGAIN;
325					break;
326				}
327				if (signal_pending(current)) {
328					retval = -ERESTARTSYS;
329					break;
330				}
331				if (!list->hiddev->exist) {
332					retval = -EIO;
333					break;
334				}
335
336				schedule();
337				set_current_state(TASK_INTERRUPTIBLE);
338			}
339
340			set_current_state(TASK_RUNNING);
341			remove_wait_queue(&list->hiddev->wait, &wait);
342		}
343
344		if (retval)
345			return retval;
346
347
348		while (list->head != list->tail &&
349		       retval + event_size <= count) {
350			if ((list->flags & HIDDEV_FLAG_UREF) == 0) {
351				if (list->buffer[list->tail].field_index !=
352				    HID_FIELD_INDEX_NONE) {
353					struct hiddev_event event;
354					event.hid = list->buffer[list->tail].usage_code;
355					event.value = list->buffer[list->tail].value;
356					if (copy_to_user(buffer + retval, &event, sizeof(struct hiddev_event)))
357						return -EFAULT;
358					retval += sizeof(struct hiddev_event);
359				}
360			} else {
361				if (list->buffer[list->tail].field_index != HID_FIELD_INDEX_NONE ||
362				    (list->flags & HIDDEV_FLAG_REPORT) != 0) {
363					if (copy_to_user(buffer + retval, list->buffer + list->tail, sizeof(struct hiddev_usage_ref)))
364						return -EFAULT;
365					retval += sizeof(struct hiddev_usage_ref);
366				}
367			}
368			list->tail = (list->tail + 1) & (HIDDEV_BUFFER_SIZE - 1);
369		}
370
371	}
372
373	return retval;
374}
375
376/*
377 * "poll" file op
378 * No kernel lock - fine
379 */
380static unsigned int hiddev_poll(struct file *file, poll_table *wait)
381{
382	struct hiddev_list *list = file->private_data;
383
384	poll_wait(file, &list->hiddev->wait, wait);
385	if (list->head != list->tail)
386		return POLLIN | POLLRDNORM;
387	if (!list->hiddev->exist)
388		return POLLERR | POLLHUP;
389	return 0;
390}
391
392/*
393 * "ioctl" file op
394 */
395static int hiddev_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
396{
397	struct hiddev_list *list = file->private_data;
398	struct hiddev *hiddev = list->hiddev;
399	struct hid_device *hid = hiddev->hid;
400	struct usb_device *dev = hid_to_usb_dev(hid);
401	struct hiddev_collection_info cinfo;
402	struct hiddev_report_info rinfo;
403	struct hiddev_field_info finfo;
404	struct hiddev_usage_ref_multi *uref_multi = NULL;
405	struct hiddev_usage_ref *uref;
406	struct hiddev_devinfo dinfo;
407	struct hid_report *report;
408	struct hid_field *field;
409	struct usbhid_device *usbhid = hid->driver_data;
410	void __user *user_arg = (void __user *)arg;
411	int i;
412
413	if (!hiddev->exist)
414		return -EIO;
415
416	switch (cmd) {
417
418	case HIDIOCGVERSION:
419		return put_user(HID_VERSION, (int __user *)arg);
420
421	case HIDIOCAPPLICATION:
422		if (arg < 0 || arg >= hid->maxapplication)
423			return -EINVAL;
424
425		for (i = 0; i < hid->maxcollection; i++)
426			if (hid->collection[i].type ==
427			    HID_COLLECTION_APPLICATION && arg-- == 0)
428				break;
429
430		if (i == hid->maxcollection)
431			return -EINVAL;
432
433		return hid->collection[i].usage;
434
435	case HIDIOCGDEVINFO:
436		dinfo.bustype = BUS_USB;
437		dinfo.busnum = dev->bus->busnum;
438		dinfo.devnum = dev->devnum;
439		dinfo.ifnum = usbhid->ifnum;
440		dinfo.vendor = le16_to_cpu(dev->descriptor.idVendor);
441		dinfo.product = le16_to_cpu(dev->descriptor.idProduct);
442		dinfo.version = le16_to_cpu(dev->descriptor.bcdDevice);
443		dinfo.num_applications = hid->maxapplication;
444		if (copy_to_user(user_arg, &dinfo, sizeof(dinfo)))
445			return -EFAULT;
446
447		return 0;
448
449	case HIDIOCGFLAG:
450		if (put_user(list->flags, (int __user *)arg))
451			return -EFAULT;
452
453		return 0;
454
455	case HIDIOCSFLAG:
456		{
457			int newflags;
458			if (get_user(newflags, (int __user *)arg))
459				return -EFAULT;
460
461			if ((newflags & ~HIDDEV_FLAGS) != 0 ||
462			    ((newflags & HIDDEV_FLAG_REPORT) != 0 &&
463			     (newflags & HIDDEV_FLAG_UREF) == 0))
464				return -EINVAL;
465
466			list->flags = newflags;
467
468			return 0;
469		}
470
471	case HIDIOCGSTRING:
472		{
473			int idx, len;
474			char *buf;
475
476			if (get_user(idx, (int __user *)arg))
477				return -EFAULT;
478
479			if ((buf = kmalloc(HID_STRING_SIZE, GFP_KERNEL)) == NULL)
480				return -ENOMEM;
481
482			if ((len = usb_string(dev, idx, buf, HID_STRING_SIZE-1)) < 0) {
483				kfree(buf);
484				return -EINVAL;
485			}
486
487			if (copy_to_user(user_arg+sizeof(int), buf, len+1)) {
488				kfree(buf);
489				return -EFAULT;
490			}
491
492			kfree(buf);
493
494			return len;
495		}
496
497	case HIDIOCINITREPORT:
498		usbhid_init_reports(hid);
499
500		return 0;
501
502	case HIDIOCGREPORT:
503		if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
504			return -EFAULT;
505
506		if (rinfo.report_type == HID_REPORT_TYPE_OUTPUT)
507			return -EINVAL;
508
509		if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
510			return -EINVAL;
511
512		usbhid_submit_report(hid, report, USB_DIR_IN);
513		usbhid_wait_io(hid);
514
515		return 0;
516
517	case HIDIOCSREPORT:
518		if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
519			return -EFAULT;
520
521		if (rinfo.report_type == HID_REPORT_TYPE_INPUT)
522			return -EINVAL;
523
524		if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
525			return -EINVAL;
526
527		usbhid_submit_report(hid, report, USB_DIR_OUT);
528		usbhid_wait_io(hid);
529
530		return 0;
531
532	case HIDIOCGREPORTINFO:
533		if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
534			return -EFAULT;
535
536		if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
537			return -EINVAL;
538
539		rinfo.num_fields = report->maxfield;
540
541		if (copy_to_user(user_arg, &rinfo, sizeof(rinfo)))
542			return -EFAULT;
543
544		return 0;
545
546	case HIDIOCGFIELDINFO:
547		if (copy_from_user(&finfo, user_arg, sizeof(finfo)))
548			return -EFAULT;
549		rinfo.report_type = finfo.report_type;
550		rinfo.report_id = finfo.report_id;
551		if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
552			return -EINVAL;
553
554		if (finfo.field_index >= report->maxfield)
555			return -EINVAL;
556
557		field = report->field[finfo.field_index];
558		memset(&finfo, 0, sizeof(finfo));
559		finfo.report_type = rinfo.report_type;
560		finfo.report_id = rinfo.report_id;
561		finfo.field_index = field->report_count - 1;
562		finfo.maxusage = field->maxusage;
563		finfo.flags = field->flags;
564		finfo.physical = field->physical;
565		finfo.logical = field->logical;
566		finfo.application = field->application;
567		finfo.logical_minimum = field->logical_minimum;
568		finfo.logical_maximum = field->logical_maximum;
569		finfo.physical_minimum = field->physical_minimum;
570		finfo.physical_maximum = field->physical_maximum;
571		finfo.unit_exponent = field->unit_exponent;
572		finfo.unit = field->unit;
573
574		if (copy_to_user(user_arg, &finfo, sizeof(finfo)))
575			return -EFAULT;
576
577		return 0;
578
579	case HIDIOCGUCODE:
580		uref_multi = kmalloc(sizeof(struct hiddev_usage_ref_multi), GFP_KERNEL);
581		if (!uref_multi)
582			return -ENOMEM;
583		uref = &uref_multi->uref;
584		if (copy_from_user(uref, user_arg, sizeof(*uref)))
585			goto fault;
586
587		rinfo.report_type = uref->report_type;
588		rinfo.report_id = uref->report_id;
589		if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
590			goto inval;
591
592		if (uref->field_index >= report->maxfield)
593			goto inval;
594
595		field = report->field[uref->field_index];
596		if (uref->usage_index >= field->maxusage)
597			goto inval;
598
599		uref->usage_code = field->usage[uref->usage_index].hid;
600
601		if (copy_to_user(user_arg, uref, sizeof(*uref)))
602			goto fault;
603
604		kfree(uref_multi);
605		return 0;
606
607	case HIDIOCGUSAGE:
608	case HIDIOCSUSAGE:
609	case HIDIOCGUSAGES:
610	case HIDIOCSUSAGES:
611	case HIDIOCGCOLLECTIONINDEX:
612		uref_multi = kmalloc(sizeof(struct hiddev_usage_ref_multi), GFP_KERNEL);
613		if (!uref_multi)
614			return -ENOMEM;
615		uref = &uref_multi->uref;
616		if (cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) {
617			if (copy_from_user(uref_multi, user_arg,
618					   sizeof(*uref_multi)))
619				goto fault;
620		} else {
621			if (copy_from_user(uref, user_arg, sizeof(*uref)))
622				goto fault;
623		}
624
625		if (cmd != HIDIOCGUSAGE &&
626		    cmd != HIDIOCGUSAGES &&
627		    uref->report_type == HID_REPORT_TYPE_INPUT)
628			goto inval;
629
630		if (uref->report_id == HID_REPORT_ID_UNKNOWN) {
631			field = hiddev_lookup_usage(hid, uref);
632			if (field == NULL)
633				goto inval;
634		} else {
635			rinfo.report_type = uref->report_type;
636			rinfo.report_id = uref->report_id;
637			if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
638				goto inval;
639
640			if (uref->field_index >= report->maxfield)
641				goto inval;
642
643			field = report->field[uref->field_index];
644
645			if (cmd == HIDIOCGCOLLECTIONINDEX) {
646				if (uref->usage_index >= field->maxusage)
647					goto inval;
648			} else if (uref->usage_index >= field->report_count)
649				goto inval;
650
651			else if ((cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) &&
652				 (uref_multi->num_values > HID_MAX_MULTI_USAGES ||
653				  uref->usage_index + uref_multi->num_values > field->report_count))
654				goto inval;
655			}
656
657		switch (cmd) {
658			case HIDIOCGUSAGE:
659				uref->value = field->value[uref->usage_index];
660				if (copy_to_user(user_arg, uref, sizeof(*uref)))
661					goto fault;
662				goto goodreturn;
663
664			case HIDIOCSUSAGE:
665				field->value[uref->usage_index] = uref->value;
666				goto goodreturn;
667
668			case HIDIOCGCOLLECTIONINDEX:
669				kfree(uref_multi);
670				return field->usage[uref->usage_index].collection_index;
671			case HIDIOCGUSAGES:
672				for (i = 0; i < uref_multi->num_values; i++)
673					uref_multi->values[i] =
674					    field->value[uref->usage_index + i];
675				if (copy_to_user(user_arg, uref_multi,
676						 sizeof(*uref_multi)))
677					goto fault;
678				goto goodreturn;
679			case HIDIOCSUSAGES:
680				for (i = 0; i < uref_multi->num_values; i++)
681					field->value[uref->usage_index + i] =
682					    uref_multi->values[i];
683				goto goodreturn;
684		}
685
686goodreturn:
687		kfree(uref_multi);
688		return 0;
689fault:
690		kfree(uref_multi);
691		return -EFAULT;
692inval:
693		kfree(uref_multi);
694		return -EINVAL;
695
696	case HIDIOCGCOLLECTIONINFO:
697		if (copy_from_user(&cinfo, user_arg, sizeof(cinfo)))
698			return -EFAULT;
699
700		if (cinfo.index >= hid->maxcollection)
701			return -EINVAL;
702
703		cinfo.type = hid->collection[cinfo.index].type;
704		cinfo.usage = hid->collection[cinfo.index].usage;
705		cinfo.level = hid->collection[cinfo.index].level;
706
707		if (copy_to_user(user_arg, &cinfo, sizeof(cinfo)))
708			return -EFAULT;
709		return 0;
710
711	default:
712
713		if (_IOC_TYPE(cmd) != 'H' || _IOC_DIR(cmd) != _IOC_READ)
714			return -EINVAL;
715
716		if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGNAME(0))) {
717			int len;
718			if (!hid->name)
719				return 0;
720			len = strlen(hid->name) + 1;
721			if (len > _IOC_SIZE(cmd))
722				 len = _IOC_SIZE(cmd);
723			return copy_to_user(user_arg, hid->name, len) ?
724				-EFAULT : len;
725		}
726
727		if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGPHYS(0))) {
728			int len;
729			if (!hid->phys)
730				return 0;
731			len = strlen(hid->phys) + 1;
732			if (len > _IOC_SIZE(cmd))
733				len = _IOC_SIZE(cmd);
734			return copy_to_user(user_arg, hid->phys, len) ?
735				-EFAULT : len;
736		}
737	}
738	return -EINVAL;
739}
740
741static const struct file_operations hiddev_fops = {
742	.owner =	THIS_MODULE,
743	.read =		hiddev_read,
744	.write =	hiddev_write,
745	.poll =		hiddev_poll,
746	.open =		hiddev_open,
747	.release =	hiddev_release,
748	.ioctl =	hiddev_ioctl,
749	.fasync =	hiddev_fasync,
750};
751
752static struct usb_class_driver hiddev_class = {
753	.name =		"hiddev%d",
754	.fops =		&hiddev_fops,
755	.minor_base =	HIDDEV_MINOR_BASE,
756};
757
758/*
759 * This is where hid.c calls us to connect a hid device to the hiddev driver
760 */
761int hiddev_connect(struct hid_device *hid)
762{
763	struct hiddev *hiddev;
764	struct usbhid_device *usbhid = hid->driver_data;
765	int i;
766	int retval;
767
768	for (i = 0; i < hid->maxcollection; i++)
769		if (hid->collection[i].type ==
770		    HID_COLLECTION_APPLICATION &&
771		    !IS_INPUT_APPLICATION(hid->collection[i].usage))
772			break;
773
774	if (i == hid->maxcollection && (hid->quirks & HID_QUIRK_HIDDEV) == 0)
775		return -1;
776
777	if (!(hiddev = kzalloc(sizeof(struct hiddev), GFP_KERNEL)))
778		return -1;
779
780	retval = usb_register_dev(usbhid->intf, &hiddev_class);
781	if (retval) {
782		err("Not able to get a minor for this device.");
783		kfree(hiddev);
784		return -1;
785	}
786
787	init_waitqueue_head(&hiddev->wait);
788	INIT_LIST_HEAD(&hiddev->list);
789	spin_lock_init(&hiddev->list_lock);
790	hiddev->hid = hid;
791	hiddev->exist = 1;
792
793	hid->minor = usbhid->intf->minor;
794	hid->hiddev = hiddev;
795
796	hiddev_table[usbhid->intf->minor - HIDDEV_MINOR_BASE] = hiddev;
797
798	return 0;
799}
800
801/*
802 * This is where hid.c calls us to disconnect a hiddev device from the
803 * corresponding hid device (usually because the usb device has disconnected)
804 */
805static struct usb_class_driver hiddev_class;
806void hiddev_disconnect(struct hid_device *hid)
807{
808	struct hiddev *hiddev = hid->hiddev;
809	struct usbhid_device *usbhid = hid->driver_data;
810
811	hiddev->exist = 0;
812
813	hiddev_table[hiddev->hid->minor - HIDDEV_MINOR_BASE] = NULL;
814	usb_deregister_dev(usbhid->intf, &hiddev_class);
815
816	if (hiddev->open) {
817		usbhid_close(hiddev->hid);
818		wake_up_interruptible(&hiddev->wait);
819	} else {
820		kfree(hiddev);
821	}
822}
823
824/* Currently this driver is a USB driver.  It's not a conventional one in
825 * the sense that it doesn't probe at the USB level.  Instead it waits to
826 * be connected by HID through the hiddev_connect / hiddev_disconnect
827 * routines.  The reason to register as a USB device is to gain part of the
828 * minor number space from the USB major.
829 *
830 * In theory, should the HID code be generalized to more than one physical
831 * medium (say, IEEE 1384), this driver will probably need to register its
832 * own major number, and in doing so, no longer need to register with USB.
833 * At that point the probe routine and hiddev_driver struct below will no
834 * longer be useful.
835 */
836
837
838/* We never attach in this manner, and rely on HID to connect us.  This
839 * is why there is no disconnect routine defined in the usb_driver either.
840 */
841static int hiddev_usbd_probe(struct usb_interface *intf,
842			     const struct usb_device_id *hiddev_info)
843{
844	return -ENODEV;
845}
846
847
848static /* const */ struct usb_driver hiddev_driver = {
849	.name =		"hiddev",
850	.probe =	hiddev_usbd_probe,
851};
852
853int __init hiddev_init(void)
854{
855	return usb_register(&hiddev_driver);
856}
857
858void hiddev_exit(void)
859{
860	usb_deregister(&hiddev_driver);
861}
862