2 * Copyright (c) 2001 Paul Stewart
3 * Copyright (c) 2001 Vojtech Pavlik
5 * HID char devices, giving access to raw HID device events.
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.
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.
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
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>
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 <linux/compat.h>
40 #ifdef CONFIG_USB_DYNAMIC_MINORS
41 #define HIDDEV_MINOR_BASE 0
42 #define HIDDEV_MINORS 256
44 #define HIDDEV_MINOR_BASE 96
45 #define HIDDEV_MINORS 16
47 #define HIDDEV_BUFFER_SIZE 2048
52 struct mutex existancelock;
53 wait_queue_head_t wait;
54 struct hid_device *hid;
55 struct list_head list;
60 struct hiddev_usage_ref buffer[HIDDEV_BUFFER_SIZE];
64 struct fasync_struct *fasync;
65 struct hiddev *hiddev;
66 struct list_head node;
67 struct mutex thread_lock;
70 static struct usb_driver hiddev_driver;
73 * Find a report, given the report's type and ID. The ID can be specified
74 * indirectly by REPORT_ID_FIRST (which returns the first report of the given
75 * type) or by (REPORT_ID_NEXT | old_id), which returns the next report of the
76 * given type which follows old_id.
78 static struct hid_report *
79 hiddev_lookup_report(struct hid_device *hid, struct hiddev_report_info *rinfo)
81 unsigned int flags = rinfo->report_id & ~HID_REPORT_ID_MASK;
82 unsigned int rid = rinfo->report_id & HID_REPORT_ID_MASK;
83 struct hid_report_enum *report_enum;
84 struct hid_report *report;
85 struct list_head *list;
87 if (rinfo->report_type < HID_REPORT_TYPE_MIN ||
88 rinfo->report_type > HID_REPORT_TYPE_MAX)
91 report_enum = hid->report_enum +
92 (rinfo->report_type - HID_REPORT_TYPE_MIN);
95 case 0: /* Nothing to do -- report_id is already set correctly */
98 case HID_REPORT_ID_FIRST:
99 if (list_empty(&report_enum->report_list))
102 list = report_enum->report_list.next;
103 report = list_entry(list, struct hid_report, list);
104 rinfo->report_id = report->id;
107 case HID_REPORT_ID_NEXT:
108 report = report_enum->report_id_hash[rid];
112 list = report->list.next;
113 if (list == &report_enum->report_list)
116 report = list_entry(list, struct hid_report, list);
117 rinfo->report_id = report->id;
124 return report_enum->report_id_hash[rinfo->report_id];
128 * Perform an exhaustive search of the report table for a usage, given its
131 static struct hid_field *
132 hiddev_lookup_usage(struct hid_device *hid, struct hiddev_usage_ref *uref)
135 struct hid_report *report;
136 struct hid_report_enum *report_enum;
137 struct hid_field *field;
139 if (uref->report_type < HID_REPORT_TYPE_MIN ||
140 uref->report_type > HID_REPORT_TYPE_MAX)
143 report_enum = hid->report_enum +
144 (uref->report_type - HID_REPORT_TYPE_MIN);
146 list_for_each_entry(report, &report_enum->report_list, list) {
147 for (i = 0; i < report->maxfield; i++) {
148 field = report->field[i];
149 for (j = 0; j < field->maxusage; j++) {
150 if (field->usage[j].hid == uref->usage_code) {
151 uref->report_id = report->id;
152 uref->field_index = i;
153 uref->usage_index = j;
163 static void hiddev_send_event(struct hid_device *hid,
164 struct hiddev_usage_ref *uref)
166 struct hiddev *hiddev = hid->hiddev;
167 struct hiddev_list *list;
170 spin_lock_irqsave(&hiddev->list_lock, flags);
171 list_for_each_entry(list, &hiddev->list, node) {
172 if (uref->field_index != HID_FIELD_INDEX_NONE ||
173 (list->flags & HIDDEV_FLAG_REPORT) != 0) {
174 list->buffer[list->head] = *uref;
175 list->head = (list->head + 1) &
176 (HIDDEV_BUFFER_SIZE - 1);
177 kill_fasync(&list->fasync, SIGIO, POLL_IN);
180 spin_unlock_irqrestore(&hiddev->list_lock, flags);
182 wake_up_interruptible(&hiddev->wait);
186 * This is where hid.c calls into hiddev to pass an event that occurred over
189 void hiddev_hid_event(struct hid_device *hid, struct hid_field *field,
190 struct hid_usage *usage, __s32 value)
192 unsigned type = field->report_type;
193 struct hiddev_usage_ref uref;
196 (type == HID_INPUT_REPORT) ? HID_REPORT_TYPE_INPUT :
197 ((type == HID_OUTPUT_REPORT) ? HID_REPORT_TYPE_OUTPUT :
198 ((type == HID_FEATURE_REPORT) ? HID_REPORT_TYPE_FEATURE : 0));
199 uref.report_id = field->report->id;
200 uref.field_index = field->index;
201 uref.usage_index = (usage - field->usage);
202 uref.usage_code = usage->hid;
205 hiddev_send_event(hid, &uref);
207 EXPORT_SYMBOL_GPL(hiddev_hid_event);
209 void hiddev_report_event(struct hid_device *hid, struct hid_report *report)
211 unsigned type = report->type;
212 struct hiddev_usage_ref uref;
214 memset(&uref, 0, sizeof(uref));
216 (type == HID_INPUT_REPORT) ? HID_REPORT_TYPE_INPUT :
217 ((type == HID_OUTPUT_REPORT) ? HID_REPORT_TYPE_OUTPUT :
218 ((type == HID_FEATURE_REPORT) ? HID_REPORT_TYPE_FEATURE : 0));
219 uref.report_id = report->id;
220 uref.field_index = HID_FIELD_INDEX_NONE;
222 hiddev_send_event(hid, &uref);
228 static int hiddev_fasync(int fd, struct file *file, int on)
230 struct hiddev_list *list = file->private_data;
232 return fasync_helper(fd, file, on, &list->fasync);
239 static int hiddev_release(struct inode * inode, struct file * file)
241 struct hiddev_list *list = file->private_data;
244 spin_lock_irqsave(&list->hiddev->list_lock, flags);
245 list_del(&list->node);
246 spin_unlock_irqrestore(&list->hiddev->list_lock, flags);
248 if (!--list->hiddev->open) {
249 if (list->hiddev->exist) {
250 usbhid_close(list->hiddev->hid);
251 usbhid_put_power(list->hiddev->hid);
265 static int hiddev_open(struct inode *inode, struct file *file)
267 struct hiddev_list *list;
268 struct usb_interface *intf;
269 struct hiddev *hiddev;
272 intf = usb_find_interface(&hiddev_driver, iminor(inode));
275 hiddev = usb_get_intfdata(intf);
277 if (!(list = kzalloc(sizeof(struct hiddev_list), GFP_KERNEL)))
279 mutex_init(&list->thread_lock);
280 list->hiddev = hiddev;
281 file->private_data = list;
284 * no need for locking because the USB major number
285 * is shared which usbcore guards against disconnect
287 if (list->hiddev->exist) {
288 if (!list->hiddev->open++) {
289 res = usbhid_open(hiddev->hid);
300 spin_lock_irq(&list->hiddev->list_lock);
301 list_add_tail(&list->node, &hiddev->list);
302 spin_unlock_irq(&list->hiddev->list_lock);
304 if (!list->hiddev->open++)
305 if (list->hiddev->exist) {
306 struct hid_device *hid = hiddev->hid;
307 res = usbhid_get_power(hid);
316 file->private_data = NULL;
324 static ssize_t hiddev_write(struct file * file, const char __user * buffer, size_t count, loff_t *ppos)
332 static ssize_t hiddev_read(struct file * file, char __user * buffer, size_t count, loff_t *ppos)
335 struct hiddev_list *list = file->private_data;
339 event_size = ((list->flags & HIDDEV_FLAG_UREF) != 0) ?
340 sizeof(struct hiddev_usage_ref) : sizeof(struct hiddev_event);
342 if (count < event_size)
345 /* lock against other threads */
346 retval = mutex_lock_interruptible(&list->thread_lock);
350 while (retval == 0) {
351 if (list->head == list->tail) {
352 prepare_to_wait(&list->hiddev->wait, &wait, TASK_INTERRUPTIBLE);
354 while (list->head == list->tail) {
355 if (file->f_flags & O_NONBLOCK) {
359 if (signal_pending(current)) {
360 retval = -ERESTARTSYS;
363 if (!list->hiddev->exist) {
368 /* let O_NONBLOCK tasks run */
369 mutex_unlock(&list->thread_lock);
371 if (mutex_lock_interruptible(&list->thread_lock))
373 set_current_state(TASK_INTERRUPTIBLE);
375 finish_wait(&list->hiddev->wait, &wait);
380 mutex_unlock(&list->thread_lock);
385 while (list->head != list->tail &&
386 retval + event_size <= count) {
387 if ((list->flags & HIDDEV_FLAG_UREF) == 0) {
388 if (list->buffer[list->tail].field_index != HID_FIELD_INDEX_NONE) {
389 struct hiddev_event event;
391 event.hid = list->buffer[list->tail].usage_code;
392 event.value = list->buffer[list->tail].value;
393 if (copy_to_user(buffer + retval, &event, sizeof(struct hiddev_event))) {
394 mutex_unlock(&list->thread_lock);
397 retval += sizeof(struct hiddev_event);
400 if (list->buffer[list->tail].field_index != HID_FIELD_INDEX_NONE ||
401 (list->flags & HIDDEV_FLAG_REPORT) != 0) {
403 if (copy_to_user(buffer + retval, list->buffer + list->tail, sizeof(struct hiddev_usage_ref))) {
404 mutex_unlock(&list->thread_lock);
407 retval += sizeof(struct hiddev_usage_ref);
410 list->tail = (list->tail + 1) & (HIDDEV_BUFFER_SIZE - 1);
414 mutex_unlock(&list->thread_lock);
421 * No kernel lock - fine
423 static unsigned int hiddev_poll(struct file *file, poll_table *wait)
425 struct hiddev_list *list = file->private_data;
427 poll_wait(file, &list->hiddev->wait, wait);
428 if (list->head != list->tail)
429 return POLLIN | POLLRDNORM;
430 if (!list->hiddev->exist)
431 return POLLERR | POLLHUP;
438 static noinline int hiddev_ioctl_usage(struct hiddev *hiddev, unsigned int cmd, void __user *user_arg)
440 struct hid_device *hid = hiddev->hid;
441 struct hiddev_report_info rinfo;
442 struct hiddev_usage_ref_multi *uref_multi = NULL;
443 struct hiddev_usage_ref *uref;
444 struct hid_report *report;
445 struct hid_field *field;
448 uref_multi = kmalloc(sizeof(struct hiddev_usage_ref_multi), GFP_KERNEL);
451 uref = &uref_multi->uref;
452 if (cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) {
453 if (copy_from_user(uref_multi, user_arg,
454 sizeof(*uref_multi)))
457 if (copy_from_user(uref, user_arg, sizeof(*uref)))
463 rinfo.report_type = uref->report_type;
464 rinfo.report_id = uref->report_id;
465 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
468 if (uref->field_index >= report->maxfield)
471 field = report->field[uref->field_index];
472 if (uref->usage_index >= field->maxusage)
475 uref->usage_code = field->usage[uref->usage_index].hid;
477 if (copy_to_user(user_arg, uref, sizeof(*uref)))
483 if (cmd != HIDIOCGUSAGE &&
484 cmd != HIDIOCGUSAGES &&
485 uref->report_type == HID_REPORT_TYPE_INPUT)
488 if (uref->report_id == HID_REPORT_ID_UNKNOWN) {
489 field = hiddev_lookup_usage(hid, uref);
493 rinfo.report_type = uref->report_type;
494 rinfo.report_id = uref->report_id;
495 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
498 if (uref->field_index >= report->maxfield)
501 field = report->field[uref->field_index];
503 if (cmd == HIDIOCGCOLLECTIONINDEX) {
504 if (uref->usage_index >= field->maxusage)
506 } else if (uref->usage_index >= field->report_count)
509 else if ((cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) &&
510 (uref_multi->num_values > HID_MAX_MULTI_USAGES ||
511 uref->usage_index + uref_multi->num_values > field->report_count))
517 uref->value = field->value[uref->usage_index];
518 if (copy_to_user(user_arg, uref, sizeof(*uref)))
523 field->value[uref->usage_index] = uref->value;
526 case HIDIOCGCOLLECTIONINDEX:
527 i = field->usage[uref->usage_index].collection_index;
531 for (i = 0; i < uref_multi->num_values; i++)
532 uref_multi->values[i] =
533 field->value[uref->usage_index + i];
534 if (copy_to_user(user_arg, uref_multi,
535 sizeof(*uref_multi)))
539 for (i = 0; i < uref_multi->num_values; i++)
540 field->value[uref->usage_index + i] =
541 uref_multi->values[i];
557 static noinline int hiddev_ioctl_string(struct hiddev *hiddev, unsigned int cmd, void __user *user_arg)
559 struct hid_device *hid = hiddev->hid;
560 struct usb_device *dev = hid_to_usb_dev(hid);
564 if (get_user(idx, (int __user *)user_arg))
567 if ((buf = kmalloc(HID_STRING_SIZE, GFP_KERNEL)) == NULL)
570 if ((len = usb_string(dev, idx, buf, HID_STRING_SIZE-1)) < 0) {
575 if (copy_to_user(user_arg+sizeof(int), buf, len+1)) {
585 static long hiddev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
587 struct hiddev_list *list = file->private_data;
588 struct hiddev *hiddev = list->hiddev;
589 struct hid_device *hid = hiddev->hid;
590 struct usb_device *dev = hid_to_usb_dev(hid);
591 struct hiddev_collection_info cinfo;
592 struct hiddev_report_info rinfo;
593 struct hiddev_field_info finfo;
594 struct hiddev_devinfo dinfo;
595 struct hid_report *report;
596 struct hid_field *field;
597 struct usbhid_device *usbhid = hid->driver_data;
598 void __user *user_arg = (void __user *)arg;
601 /* Called without BKL by compat methods so no BKL taken */
603 /* FIXME: Who or what stop this racing with a disconnect ?? */
610 return put_user(HID_VERSION, (int __user *)arg);
612 case HIDIOCAPPLICATION:
613 if (arg < 0 || arg >= hid->maxapplication)
616 for (i = 0; i < hid->maxcollection; i++)
617 if (hid->collection[i].type ==
618 HID_COLLECTION_APPLICATION && arg-- == 0)
621 if (i == hid->maxcollection)
624 return hid->collection[i].usage;
627 dinfo.bustype = BUS_USB;
628 dinfo.busnum = dev->bus->busnum;
629 dinfo.devnum = dev->devnum;
630 dinfo.ifnum = usbhid->ifnum;
631 dinfo.vendor = le16_to_cpu(dev->descriptor.idVendor);
632 dinfo.product = le16_to_cpu(dev->descriptor.idProduct);
633 dinfo.version = le16_to_cpu(dev->descriptor.bcdDevice);
634 dinfo.num_applications = hid->maxapplication;
635 if (copy_to_user(user_arg, &dinfo, sizeof(dinfo)))
641 if (put_user(list->flags, (int __user *)arg))
649 if (get_user(newflags, (int __user *)arg))
652 if ((newflags & ~HIDDEV_FLAGS) != 0 ||
653 ((newflags & HIDDEV_FLAG_REPORT) != 0 &&
654 (newflags & HIDDEV_FLAG_UREF) == 0))
657 list->flags = newflags;
663 mutex_lock(&hiddev->existancelock);
665 r = hiddev_ioctl_string(hiddev, cmd, user_arg);
668 mutex_unlock(&hiddev->existancelock);
671 case HIDIOCINITREPORT:
672 mutex_lock(&hiddev->existancelock);
673 if (!hiddev->exist) {
674 mutex_unlock(&hiddev->existancelock);
677 usbhid_init_reports(hid);
678 mutex_unlock(&hiddev->existancelock);
683 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
686 if (rinfo.report_type == HID_REPORT_TYPE_OUTPUT)
689 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
692 mutex_lock(&hiddev->existancelock);
694 usbhid_submit_report(hid, report, USB_DIR_IN);
697 mutex_unlock(&hiddev->existancelock);
702 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
705 if (rinfo.report_type == HID_REPORT_TYPE_INPUT)
708 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
711 mutex_lock(&hiddev->existancelock);
713 usbhid_submit_report(hid, report, USB_DIR_OUT);
716 mutex_unlock(&hiddev->existancelock);
720 case HIDIOCGREPORTINFO:
721 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
724 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
727 rinfo.num_fields = report->maxfield;
729 if (copy_to_user(user_arg, &rinfo, sizeof(rinfo)))
734 case HIDIOCGFIELDINFO:
735 if (copy_from_user(&finfo, user_arg, sizeof(finfo)))
737 rinfo.report_type = finfo.report_type;
738 rinfo.report_id = finfo.report_id;
739 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
742 if (finfo.field_index >= report->maxfield)
745 field = report->field[finfo.field_index];
746 memset(&finfo, 0, sizeof(finfo));
747 finfo.report_type = rinfo.report_type;
748 finfo.report_id = rinfo.report_id;
749 finfo.field_index = field->report_count - 1;
750 finfo.maxusage = field->maxusage;
751 finfo.flags = field->flags;
752 finfo.physical = field->physical;
753 finfo.logical = field->logical;
754 finfo.application = field->application;
755 finfo.logical_minimum = field->logical_minimum;
756 finfo.logical_maximum = field->logical_maximum;
757 finfo.physical_minimum = field->physical_minimum;
758 finfo.physical_maximum = field->physical_maximum;
759 finfo.unit_exponent = field->unit_exponent;
760 finfo.unit = field->unit;
762 if (copy_to_user(user_arg, &finfo, sizeof(finfo)))
773 case HIDIOCGCOLLECTIONINDEX:
774 mutex_lock(&hiddev->existancelock);
776 r = hiddev_ioctl_usage(hiddev, cmd, user_arg);
779 mutex_unlock(&hiddev->existancelock);
782 case HIDIOCGCOLLECTIONINFO:
783 if (copy_from_user(&cinfo, user_arg, sizeof(cinfo)))
786 if (cinfo.index >= hid->maxcollection)
789 cinfo.type = hid->collection[cinfo.index].type;
790 cinfo.usage = hid->collection[cinfo.index].usage;
791 cinfo.level = hid->collection[cinfo.index].level;
793 if (copy_to_user(user_arg, &cinfo, sizeof(cinfo)))
799 if (_IOC_TYPE(cmd) != 'H' || _IOC_DIR(cmd) != _IOC_READ)
802 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGNAME(0))) {
806 len = strlen(hid->name) + 1;
807 if (len > _IOC_SIZE(cmd))
808 len = _IOC_SIZE(cmd);
809 return copy_to_user(user_arg, hid->name, len) ?
813 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGPHYS(0))) {
817 len = strlen(hid->phys) + 1;
818 if (len > _IOC_SIZE(cmd))
819 len = _IOC_SIZE(cmd);
820 return copy_to_user(user_arg, hid->phys, len) ?
828 static long hiddev_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
830 return hiddev_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
834 static const struct file_operations hiddev_fops = {
835 .owner = THIS_MODULE,
837 .write = hiddev_write,
840 .release = hiddev_release,
841 .unlocked_ioctl = hiddev_ioctl,
842 .fasync = hiddev_fasync,
844 .compat_ioctl = hiddev_compat_ioctl,
848 static char *hiddev_devnode(struct device *dev, mode_t *mode)
850 return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev));
853 static struct usb_class_driver hiddev_class = {
855 .devnode = hiddev_devnode,
856 .fops = &hiddev_fops,
857 .minor_base = HIDDEV_MINOR_BASE,
861 * This is where hid.c calls us to connect a hid device to the hiddev driver
863 int hiddev_connect(struct hid_device *hid, unsigned int force)
865 struct hiddev *hiddev;
866 struct usbhid_device *usbhid = hid->driver_data;
871 for (i = 0; i < hid->maxcollection; i++)
872 if (hid->collection[i].type ==
873 HID_COLLECTION_APPLICATION &&
874 !IS_INPUT_APPLICATION(hid->collection[i].usage))
877 if (i == hid->maxcollection)
881 if (!(hiddev = kzalloc(sizeof(struct hiddev), GFP_KERNEL)))
884 init_waitqueue_head(&hiddev->wait);
885 INIT_LIST_HEAD(&hiddev->list);
886 spin_lock_init(&hiddev->list_lock);
887 mutex_init(&hiddev->existancelock);
888 hid->hiddev = hiddev;
891 usb_set_intfdata(usbhid->intf, usbhid);
892 retval = usb_register_dev(usbhid->intf, &hiddev_class);
894 err_hid("Not able to get a minor for this device.");
903 * This is where hid.c calls us to disconnect a hiddev device from the
904 * corresponding hid device (usually because the usb device has disconnected)
906 static struct usb_class_driver hiddev_class;
907 void hiddev_disconnect(struct hid_device *hid)
909 struct hiddev *hiddev = hid->hiddev;
910 struct usbhid_device *usbhid = hid->driver_data;
912 mutex_lock(&hiddev->existancelock);
914 mutex_unlock(&hiddev->existancelock);
916 usb_deregister_dev(usbhid->intf, &hiddev_class);
919 usbhid_close(hiddev->hid);
920 wake_up_interruptible(&hiddev->wait);
926 /* Currently this driver is a USB driver. It's not a conventional one in
927 * the sense that it doesn't probe at the USB level. Instead it waits to
928 * be connected by HID through the hiddev_connect / hiddev_disconnect
929 * routines. The reason to register as a USB device is to gain part of the
930 * minor number space from the USB major.
932 * In theory, should the HID code be generalized to more than one physical
933 * medium (say, IEEE 1384), this driver will probably need to register its
934 * own major number, and in doing so, no longer need to register with USB.
935 * At that point the probe routine and hiddev_driver struct below will no
940 /* We never attach in this manner, and rely on HID to connect us. This
941 * is why there is no disconnect routine defined in the usb_driver either.
943 static int hiddev_usbd_probe(struct usb_interface *intf,
944 const struct usb_device_id *hiddev_info)
949 static /* const */ struct usb_driver hiddev_driver = {
951 .probe = hiddev_usbd_probe,
954 int __init hiddev_init(void)
956 return usb_register(&hiddev_driver);
959 void hiddev_exit(void)
961 usb_deregister(&hiddev_driver);