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 hid_device *hid;
270 struct hiddev *hiddev;
273 intf = usb_find_interface(&hiddev_driver, iminor(inode));
276 hid = usb_get_intfdata(intf);
277 hiddev = hid->hiddev;
279 if (!(list = kzalloc(sizeof(struct hiddev_list), GFP_KERNEL)))
281 mutex_init(&list->thread_lock);
282 list->hiddev = hiddev;
283 file->private_data = list;
286 * no need for locking because the USB major number
287 * is shared which usbcore guards against disconnect
289 if (list->hiddev->exist) {
290 if (!list->hiddev->open++) {
291 res = usbhid_open(hiddev->hid);
302 spin_lock_irq(&list->hiddev->list_lock);
303 list_add_tail(&list->node, &hiddev->list);
304 spin_unlock_irq(&list->hiddev->list_lock);
306 if (!list->hiddev->open++)
307 if (list->hiddev->exist) {
308 struct hid_device *hid = hiddev->hid;
309 res = usbhid_get_power(hid);
318 file->private_data = NULL;
326 static ssize_t hiddev_write(struct file * file, const char __user * buffer, size_t count, loff_t *ppos)
334 static ssize_t hiddev_read(struct file * file, char __user * buffer, size_t count, loff_t *ppos)
337 struct hiddev_list *list = file->private_data;
341 event_size = ((list->flags & HIDDEV_FLAG_UREF) != 0) ?
342 sizeof(struct hiddev_usage_ref) : sizeof(struct hiddev_event);
344 if (count < event_size)
347 /* lock against other threads */
348 retval = mutex_lock_interruptible(&list->thread_lock);
352 while (retval == 0) {
353 if (list->head == list->tail) {
354 prepare_to_wait(&list->hiddev->wait, &wait, TASK_INTERRUPTIBLE);
356 while (list->head == list->tail) {
357 if (file->f_flags & O_NONBLOCK) {
361 if (signal_pending(current)) {
362 retval = -ERESTARTSYS;
365 if (!list->hiddev->exist) {
370 /* let O_NONBLOCK tasks run */
371 mutex_unlock(&list->thread_lock);
373 if (mutex_lock_interruptible(&list->thread_lock))
375 set_current_state(TASK_INTERRUPTIBLE);
377 finish_wait(&list->hiddev->wait, &wait);
382 mutex_unlock(&list->thread_lock);
387 while (list->head != list->tail &&
388 retval + event_size <= count) {
389 if ((list->flags & HIDDEV_FLAG_UREF) == 0) {
390 if (list->buffer[list->tail].field_index != HID_FIELD_INDEX_NONE) {
391 struct hiddev_event event;
393 event.hid = list->buffer[list->tail].usage_code;
394 event.value = list->buffer[list->tail].value;
395 if (copy_to_user(buffer + retval, &event, sizeof(struct hiddev_event))) {
396 mutex_unlock(&list->thread_lock);
399 retval += sizeof(struct hiddev_event);
402 if (list->buffer[list->tail].field_index != HID_FIELD_INDEX_NONE ||
403 (list->flags & HIDDEV_FLAG_REPORT) != 0) {
405 if (copy_to_user(buffer + retval, list->buffer + list->tail, sizeof(struct hiddev_usage_ref))) {
406 mutex_unlock(&list->thread_lock);
409 retval += sizeof(struct hiddev_usage_ref);
412 list->tail = (list->tail + 1) & (HIDDEV_BUFFER_SIZE - 1);
416 mutex_unlock(&list->thread_lock);
423 * No kernel lock - fine
425 static unsigned int hiddev_poll(struct file *file, poll_table *wait)
427 struct hiddev_list *list = file->private_data;
429 poll_wait(file, &list->hiddev->wait, wait);
430 if (list->head != list->tail)
431 return POLLIN | POLLRDNORM;
432 if (!list->hiddev->exist)
433 return POLLERR | POLLHUP;
440 static noinline int hiddev_ioctl_usage(struct hiddev *hiddev, unsigned int cmd, void __user *user_arg)
442 struct hid_device *hid = hiddev->hid;
443 struct hiddev_report_info rinfo;
444 struct hiddev_usage_ref_multi *uref_multi = NULL;
445 struct hiddev_usage_ref *uref;
446 struct hid_report *report;
447 struct hid_field *field;
450 uref_multi = kmalloc(sizeof(struct hiddev_usage_ref_multi), GFP_KERNEL);
453 uref = &uref_multi->uref;
454 if (cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) {
455 if (copy_from_user(uref_multi, user_arg,
456 sizeof(*uref_multi)))
459 if (copy_from_user(uref, user_arg, sizeof(*uref)))
465 rinfo.report_type = uref->report_type;
466 rinfo.report_id = uref->report_id;
467 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
470 if (uref->field_index >= report->maxfield)
473 field = report->field[uref->field_index];
474 if (uref->usage_index >= field->maxusage)
477 uref->usage_code = field->usage[uref->usage_index].hid;
479 if (copy_to_user(user_arg, uref, sizeof(*uref)))
485 if (cmd != HIDIOCGUSAGE &&
486 cmd != HIDIOCGUSAGES &&
487 uref->report_type == HID_REPORT_TYPE_INPUT)
490 if (uref->report_id == HID_REPORT_ID_UNKNOWN) {
491 field = hiddev_lookup_usage(hid, uref);
495 rinfo.report_type = uref->report_type;
496 rinfo.report_id = uref->report_id;
497 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
500 if (uref->field_index >= report->maxfield)
503 field = report->field[uref->field_index];
505 if (cmd == HIDIOCGCOLLECTIONINDEX) {
506 if (uref->usage_index >= field->maxusage)
508 } else if (uref->usage_index >= field->report_count)
511 else if ((cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) &&
512 (uref_multi->num_values > HID_MAX_MULTI_USAGES ||
513 uref->usage_index + uref_multi->num_values > field->report_count))
519 uref->value = field->value[uref->usage_index];
520 if (copy_to_user(user_arg, uref, sizeof(*uref)))
525 field->value[uref->usage_index] = uref->value;
528 case HIDIOCGCOLLECTIONINDEX:
529 i = field->usage[uref->usage_index].collection_index;
533 for (i = 0; i < uref_multi->num_values; i++)
534 uref_multi->values[i] =
535 field->value[uref->usage_index + i];
536 if (copy_to_user(user_arg, uref_multi,
537 sizeof(*uref_multi)))
541 for (i = 0; i < uref_multi->num_values; i++)
542 field->value[uref->usage_index + i] =
543 uref_multi->values[i];
559 static noinline int hiddev_ioctl_string(struct hiddev *hiddev, unsigned int cmd, void __user *user_arg)
561 struct hid_device *hid = hiddev->hid;
562 struct usb_device *dev = hid_to_usb_dev(hid);
566 if (get_user(idx, (int __user *)user_arg))
569 if ((buf = kmalloc(HID_STRING_SIZE, GFP_KERNEL)) == NULL)
572 if ((len = usb_string(dev, idx, buf, HID_STRING_SIZE-1)) < 0) {
577 if (copy_to_user(user_arg+sizeof(int), buf, len+1)) {
587 static long hiddev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
589 struct hiddev_list *list = file->private_data;
590 struct hiddev *hiddev = list->hiddev;
591 struct hid_device *hid = hiddev->hid;
592 struct usb_device *dev;
593 struct hiddev_collection_info cinfo;
594 struct hiddev_report_info rinfo;
595 struct hiddev_field_info finfo;
596 struct hiddev_devinfo dinfo;
597 struct hid_report *report;
598 struct hid_field *field;
599 struct usbhid_device *usbhid = hid->driver_data;
600 void __user *user_arg = (void __user *)arg;
603 /* Called without BKL by compat methods so no BKL taken */
605 /* FIXME: Who or what stop this racing with a disconnect ?? */
606 if (!hiddev->exist || !hid)
609 dev = hid_to_usb_dev(hid);
614 return put_user(HID_VERSION, (int __user *)arg);
616 case HIDIOCAPPLICATION:
617 if (arg < 0 || arg >= hid->maxapplication)
620 for (i = 0; i < hid->maxcollection; i++)
621 if (hid->collection[i].type ==
622 HID_COLLECTION_APPLICATION && arg-- == 0)
625 if (i == hid->maxcollection)
628 return hid->collection[i].usage;
631 dinfo.bustype = BUS_USB;
632 dinfo.busnum = dev->bus->busnum;
633 dinfo.devnum = dev->devnum;
634 dinfo.ifnum = usbhid->ifnum;
635 dinfo.vendor = le16_to_cpu(dev->descriptor.idVendor);
636 dinfo.product = le16_to_cpu(dev->descriptor.idProduct);
637 dinfo.version = le16_to_cpu(dev->descriptor.bcdDevice);
638 dinfo.num_applications = hid->maxapplication;
639 if (copy_to_user(user_arg, &dinfo, sizeof(dinfo)))
645 if (put_user(list->flags, (int __user *)arg))
653 if (get_user(newflags, (int __user *)arg))
656 if ((newflags & ~HIDDEV_FLAGS) != 0 ||
657 ((newflags & HIDDEV_FLAG_REPORT) != 0 &&
658 (newflags & HIDDEV_FLAG_UREF) == 0))
661 list->flags = newflags;
667 mutex_lock(&hiddev->existancelock);
669 r = hiddev_ioctl_string(hiddev, cmd, user_arg);
672 mutex_unlock(&hiddev->existancelock);
675 case HIDIOCINITREPORT:
676 mutex_lock(&hiddev->existancelock);
677 if (!hiddev->exist) {
678 mutex_unlock(&hiddev->existancelock);
681 usbhid_init_reports(hid);
682 mutex_unlock(&hiddev->existancelock);
687 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
690 if (rinfo.report_type == HID_REPORT_TYPE_OUTPUT)
693 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
696 mutex_lock(&hiddev->existancelock);
698 usbhid_submit_report(hid, report, USB_DIR_IN);
701 mutex_unlock(&hiddev->existancelock);
706 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
709 if (rinfo.report_type == HID_REPORT_TYPE_INPUT)
712 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
715 mutex_lock(&hiddev->existancelock);
717 usbhid_submit_report(hid, report, USB_DIR_OUT);
720 mutex_unlock(&hiddev->existancelock);
724 case HIDIOCGREPORTINFO:
725 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
728 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
731 rinfo.num_fields = report->maxfield;
733 if (copy_to_user(user_arg, &rinfo, sizeof(rinfo)))
738 case HIDIOCGFIELDINFO:
739 if (copy_from_user(&finfo, user_arg, sizeof(finfo)))
741 rinfo.report_type = finfo.report_type;
742 rinfo.report_id = finfo.report_id;
743 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
746 if (finfo.field_index >= report->maxfield)
749 field = report->field[finfo.field_index];
750 memset(&finfo, 0, sizeof(finfo));
751 finfo.report_type = rinfo.report_type;
752 finfo.report_id = rinfo.report_id;
753 finfo.field_index = field->report_count - 1;
754 finfo.maxusage = field->maxusage;
755 finfo.flags = field->flags;
756 finfo.physical = field->physical;
757 finfo.logical = field->logical;
758 finfo.application = field->application;
759 finfo.logical_minimum = field->logical_minimum;
760 finfo.logical_maximum = field->logical_maximum;
761 finfo.physical_minimum = field->physical_minimum;
762 finfo.physical_maximum = field->physical_maximum;
763 finfo.unit_exponent = field->unit_exponent;
764 finfo.unit = field->unit;
766 if (copy_to_user(user_arg, &finfo, sizeof(finfo)))
777 case HIDIOCGCOLLECTIONINDEX:
778 mutex_lock(&hiddev->existancelock);
780 r = hiddev_ioctl_usage(hiddev, cmd, user_arg);
783 mutex_unlock(&hiddev->existancelock);
786 case HIDIOCGCOLLECTIONINFO:
787 if (copy_from_user(&cinfo, user_arg, sizeof(cinfo)))
790 if (cinfo.index >= hid->maxcollection)
793 cinfo.type = hid->collection[cinfo.index].type;
794 cinfo.usage = hid->collection[cinfo.index].usage;
795 cinfo.level = hid->collection[cinfo.index].level;
797 if (copy_to_user(user_arg, &cinfo, sizeof(cinfo)))
803 if (_IOC_TYPE(cmd) != 'H' || _IOC_DIR(cmd) != _IOC_READ)
806 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGNAME(0))) {
810 len = strlen(hid->name) + 1;
811 if (len > _IOC_SIZE(cmd))
812 len = _IOC_SIZE(cmd);
813 return copy_to_user(user_arg, hid->name, len) ?
817 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGPHYS(0))) {
821 len = strlen(hid->phys) + 1;
822 if (len > _IOC_SIZE(cmd))
823 len = _IOC_SIZE(cmd);
824 return copy_to_user(user_arg, hid->phys, len) ?
832 static long hiddev_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
834 return hiddev_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
838 static const struct file_operations hiddev_fops = {
839 .owner = THIS_MODULE,
841 .write = hiddev_write,
844 .release = hiddev_release,
845 .unlocked_ioctl = hiddev_ioctl,
846 .fasync = hiddev_fasync,
848 .compat_ioctl = hiddev_compat_ioctl,
852 static char *hiddev_devnode(struct device *dev, mode_t *mode)
854 return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev));
857 static struct usb_class_driver hiddev_class = {
859 .devnode = hiddev_devnode,
860 .fops = &hiddev_fops,
861 .minor_base = HIDDEV_MINOR_BASE,
865 * This is where hid.c calls us to connect a hid device to the hiddev driver
867 int hiddev_connect(struct hid_device *hid, unsigned int force)
869 struct hiddev *hiddev;
870 struct usbhid_device *usbhid = hid->driver_data;
875 for (i = 0; i < hid->maxcollection; i++)
876 if (hid->collection[i].type ==
877 HID_COLLECTION_APPLICATION &&
878 !IS_INPUT_APPLICATION(hid->collection[i].usage))
881 if (i == hid->maxcollection)
885 if (!(hiddev = kzalloc(sizeof(struct hiddev), GFP_KERNEL)))
888 init_waitqueue_head(&hiddev->wait);
889 INIT_LIST_HEAD(&hiddev->list);
890 spin_lock_init(&hiddev->list_lock);
891 mutex_init(&hiddev->existancelock);
892 hid->hiddev = hiddev;
895 retval = usb_register_dev(usbhid->intf, &hiddev_class);
897 err_hid("Not able to get a minor for this device.");
906 * This is where hid.c calls us to disconnect a hiddev device from the
907 * corresponding hid device (usually because the usb device has disconnected)
909 static struct usb_class_driver hiddev_class;
910 void hiddev_disconnect(struct hid_device *hid)
912 struct hiddev *hiddev = hid->hiddev;
913 struct usbhid_device *usbhid = hid->driver_data;
915 mutex_lock(&hiddev->existancelock);
917 mutex_unlock(&hiddev->existancelock);
919 usb_deregister_dev(usbhid->intf, &hiddev_class);
922 usbhid_close(hiddev->hid);
923 wake_up_interruptible(&hiddev->wait);
929 /* Currently this driver is a USB driver. It's not a conventional one in
930 * the sense that it doesn't probe at the USB level. Instead it waits to
931 * be connected by HID through the hiddev_connect / hiddev_disconnect
932 * routines. The reason to register as a USB device is to gain part of the
933 * minor number space from the USB major.
935 * In theory, should the HID code be generalized to more than one physical
936 * medium (say, IEEE 1384), this driver will probably need to register its
937 * own major number, and in doing so, no longer need to register with USB.
938 * At that point the probe routine and hiddev_driver struct below will no
943 /* We never attach in this manner, and rely on HID to connect us. This
944 * is why there is no disconnect routine defined in the usb_driver either.
946 static int hiddev_usbd_probe(struct usb_interface *intf,
947 const struct usb_device_id *hiddev_info)
952 static /* const */ struct usb_driver hiddev_driver = {
954 .probe = hiddev_usbd_probe,
957 int __init hiddev_init(void)
959 return usb_register(&hiddev_driver);
962 void hiddev_exit(void)
964 usb_deregister(&hiddev_driver);