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/sched/signal.h>
31 #include <linux/module.h>
32 #include <linux/init.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>
38 #include <linux/vmalloc.h>
39 #include <linux/nospec.h>
42 #ifdef CONFIG_USB_DYNAMIC_MINORS
43 #define HIDDEV_MINOR_BASE 0
44 #define HIDDEV_MINORS 256
46 #define HIDDEV_MINOR_BASE 96
47 #define HIDDEV_MINORS 16
49 #define HIDDEV_BUFFER_SIZE 2048
52 struct hiddev_usage_ref buffer[HIDDEV_BUFFER_SIZE];
56 struct fasync_struct *fasync;
57 struct hiddev *hiddev;
58 struct list_head node;
59 struct mutex thread_lock;
63 * Find a report, given the report's type and ID. The ID can be specified
64 * indirectly by REPORT_ID_FIRST (which returns the first report of the given
65 * type) or by (REPORT_ID_NEXT | old_id), which returns the next report of the
66 * given type which follows old_id.
68 static struct hid_report *
69 hiddev_lookup_report(struct hid_device *hid, struct hiddev_report_info *rinfo)
71 unsigned int flags = rinfo->report_id & ~HID_REPORT_ID_MASK;
72 unsigned int rid = rinfo->report_id & HID_REPORT_ID_MASK;
73 struct hid_report_enum *report_enum;
74 struct hid_report *report;
75 struct list_head *list;
77 if (rinfo->report_type < HID_REPORT_TYPE_MIN ||
78 rinfo->report_type > HID_REPORT_TYPE_MAX)
81 report_enum = hid->report_enum +
82 (rinfo->report_type - HID_REPORT_TYPE_MIN);
85 case 0: /* Nothing to do -- report_id is already set correctly */
88 case HID_REPORT_ID_FIRST:
89 if (list_empty(&report_enum->report_list))
92 list = report_enum->report_list.next;
93 report = list_entry(list, struct hid_report, list);
94 rinfo->report_id = report->id;
97 case HID_REPORT_ID_NEXT:
98 report = report_enum->report_id_hash[rid];
102 list = report->list.next;
103 if (list == &report_enum->report_list)
106 report = list_entry(list, struct hid_report, list);
107 rinfo->report_id = report->id;
114 return report_enum->report_id_hash[rinfo->report_id];
118 * Perform an exhaustive search of the report table for a usage, given its
121 static struct hid_field *
122 hiddev_lookup_usage(struct hid_device *hid, struct hiddev_usage_ref *uref)
125 struct hid_report *report;
126 struct hid_report_enum *report_enum;
127 struct hid_field *field;
129 if (uref->report_type < HID_REPORT_TYPE_MIN ||
130 uref->report_type > HID_REPORT_TYPE_MAX)
133 report_enum = hid->report_enum +
134 (uref->report_type - HID_REPORT_TYPE_MIN);
136 list_for_each_entry(report, &report_enum->report_list, list) {
137 for (i = 0; i < report->maxfield; i++) {
138 field = report->field[i];
139 for (j = 0; j < field->maxusage; j++) {
140 if (field->usage[j].hid == uref->usage_code) {
141 uref->report_id = report->id;
142 uref->field_index = i;
143 uref->usage_index = j;
153 static void hiddev_send_event(struct hid_device *hid,
154 struct hiddev_usage_ref *uref)
156 struct hiddev *hiddev = hid->hiddev;
157 struct hiddev_list *list;
160 spin_lock_irqsave(&hiddev->list_lock, flags);
161 list_for_each_entry(list, &hiddev->list, node) {
162 if (uref->field_index != HID_FIELD_INDEX_NONE ||
163 (list->flags & HIDDEV_FLAG_REPORT) != 0) {
164 list->buffer[list->head] = *uref;
165 list->head = (list->head + 1) &
166 (HIDDEV_BUFFER_SIZE - 1);
167 kill_fasync(&list->fasync, SIGIO, POLL_IN);
170 spin_unlock_irqrestore(&hiddev->list_lock, flags);
172 wake_up_interruptible(&hiddev->wait);
176 * This is where hid.c calls into hiddev to pass an event that occurred over
179 void hiddev_hid_event(struct hid_device *hid, struct hid_field *field,
180 struct hid_usage *usage, __s32 value)
182 unsigned type = field->report_type;
183 struct hiddev_usage_ref uref;
186 (type == HID_INPUT_REPORT) ? HID_REPORT_TYPE_INPUT :
187 ((type == HID_OUTPUT_REPORT) ? HID_REPORT_TYPE_OUTPUT :
188 ((type == HID_FEATURE_REPORT) ? HID_REPORT_TYPE_FEATURE : 0));
189 uref.report_id = field->report->id;
190 uref.field_index = field->index;
191 uref.usage_index = (usage - field->usage);
192 uref.usage_code = usage->hid;
195 hiddev_send_event(hid, &uref);
197 EXPORT_SYMBOL_GPL(hiddev_hid_event);
199 void hiddev_report_event(struct hid_device *hid, struct hid_report *report)
201 unsigned type = report->type;
202 struct hiddev_usage_ref uref;
204 memset(&uref, 0, sizeof(uref));
206 (type == HID_INPUT_REPORT) ? HID_REPORT_TYPE_INPUT :
207 ((type == HID_OUTPUT_REPORT) ? HID_REPORT_TYPE_OUTPUT :
208 ((type == HID_FEATURE_REPORT) ? HID_REPORT_TYPE_FEATURE : 0));
209 uref.report_id = report->id;
210 uref.field_index = HID_FIELD_INDEX_NONE;
212 hiddev_send_event(hid, &uref);
218 static int hiddev_fasync(int fd, struct file *file, int on)
220 struct hiddev_list *list = file->private_data;
222 return fasync_helper(fd, file, on, &list->fasync);
229 static int hiddev_release(struct inode * inode, struct file * file)
231 struct hiddev_list *list = file->private_data;
234 spin_lock_irqsave(&list->hiddev->list_lock, flags);
235 list_del(&list->node);
236 spin_unlock_irqrestore(&list->hiddev->list_lock, flags);
238 mutex_lock(&list->hiddev->existancelock);
239 if (!--list->hiddev->open) {
240 if (list->hiddev->exist) {
241 hid_hw_close(list->hiddev->hid);
242 hid_hw_power(list->hiddev->hid, PM_HINT_NORMAL);
244 mutex_unlock(&list->hiddev->existancelock);
251 mutex_unlock(&list->hiddev->existancelock);
260 static int hiddev_open(struct inode *inode, struct file *file)
262 struct hiddev_list *list;
263 struct usb_interface *intf;
264 struct hid_device *hid;
265 struct hiddev *hiddev;
268 intf = usbhid_find_interface(iminor(inode));
271 hid = usb_get_intfdata(intf);
272 hiddev = hid->hiddev;
274 if (!(list = vzalloc(sizeof(struct hiddev_list))))
276 mutex_init(&list->thread_lock);
277 list->hiddev = hiddev;
278 file->private_data = list;
281 * no need for locking because the USB major number
282 * is shared which usbcore guards against disconnect
284 if (list->hiddev->exist) {
285 if (!list->hiddev->open++) {
286 res = hid_hw_open(hiddev->hid);
295 spin_lock_irq(&list->hiddev->list_lock);
296 list_add_tail(&list->node, &hiddev->list);
297 spin_unlock_irq(&list->hiddev->list_lock);
299 mutex_lock(&hiddev->existancelock);
300 if (!list->hiddev->open++)
301 if (list->hiddev->exist) {
302 struct hid_device *hid = hiddev->hid;
303 res = hid_hw_power(hid, PM_HINT_FULLON);
306 res = hid_hw_open(hid);
308 goto bail_normal_power;
310 mutex_unlock(&hiddev->existancelock);
313 hid_hw_power(hid, PM_HINT_NORMAL);
315 mutex_unlock(&hiddev->existancelock);
317 file->private_data = NULL;
325 static ssize_t hiddev_write(struct file * file, const char __user * buffer, size_t count, loff_t *ppos)
333 static ssize_t hiddev_read(struct file * file, char __user * buffer, size_t count, loff_t *ppos)
336 struct hiddev_list *list = file->private_data;
340 event_size = ((list->flags & HIDDEV_FLAG_UREF) != 0) ?
341 sizeof(struct hiddev_usage_ref) : sizeof(struct hiddev_event);
343 if (count < event_size)
346 /* lock against other threads */
347 retval = mutex_lock_interruptible(&list->thread_lock);
351 while (retval == 0) {
352 if (list->head == list->tail) {
353 prepare_to_wait(&list->hiddev->wait, &wait, TASK_INTERRUPTIBLE);
355 while (list->head == list->tail) {
356 if (signal_pending(current)) {
357 retval = -ERESTARTSYS;
360 if (!list->hiddev->exist) {
364 if (file->f_flags & O_NONBLOCK) {
369 /* let O_NONBLOCK tasks run */
370 mutex_unlock(&list->thread_lock);
372 if (mutex_lock_interruptible(&list->thread_lock)) {
373 finish_wait(&list->hiddev->wait, &wait);
376 set_current_state(TASK_INTERRUPTIBLE);
378 finish_wait(&list->hiddev->wait, &wait);
383 mutex_unlock(&list->thread_lock);
388 while (list->head != list->tail &&
389 retval + event_size <= count) {
390 if ((list->flags & HIDDEV_FLAG_UREF) == 0) {
391 if (list->buffer[list->tail].field_index != HID_FIELD_INDEX_NONE) {
392 struct hiddev_event event;
394 event.hid = list->buffer[list->tail].usage_code;
395 event.value = list->buffer[list->tail].value;
396 if (copy_to_user(buffer + retval, &event, sizeof(struct hiddev_event))) {
397 mutex_unlock(&list->thread_lock);
400 retval += sizeof(struct hiddev_event);
403 if (list->buffer[list->tail].field_index != HID_FIELD_INDEX_NONE ||
404 (list->flags & HIDDEV_FLAG_REPORT) != 0) {
406 if (copy_to_user(buffer + retval, list->buffer + list->tail, sizeof(struct hiddev_usage_ref))) {
407 mutex_unlock(&list->thread_lock);
410 retval += sizeof(struct hiddev_usage_ref);
413 list->tail = (list->tail + 1) & (HIDDEV_BUFFER_SIZE - 1);
417 mutex_unlock(&list->thread_lock);
424 * No kernel lock - fine
426 static __poll_t hiddev_poll(struct file *file, poll_table *wait)
428 struct hiddev_list *list = file->private_data;
430 poll_wait(file, &list->hiddev->wait, wait);
431 if (list->head != list->tail)
432 return EPOLLIN | EPOLLRDNORM;
433 if (!list->hiddev->exist)
434 return EPOLLERR | EPOLLHUP;
441 static noinline int hiddev_ioctl_usage(struct hiddev *hiddev, unsigned int cmd, void __user *user_arg)
443 struct hid_device *hid = hiddev->hid;
444 struct hiddev_report_info rinfo;
445 struct hiddev_usage_ref_multi *uref_multi = NULL;
446 struct hiddev_usage_ref *uref;
447 struct hid_report *report;
448 struct hid_field *field;
451 uref_multi = kmalloc(sizeof(struct hiddev_usage_ref_multi), GFP_KERNEL);
454 uref = &uref_multi->uref;
455 if (cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) {
456 if (copy_from_user(uref_multi, user_arg,
457 sizeof(*uref_multi)))
460 if (copy_from_user(uref, user_arg, sizeof(*uref)))
466 rinfo.report_type = uref->report_type;
467 rinfo.report_id = uref->report_id;
468 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
471 if (uref->field_index >= report->maxfield)
473 uref->field_index = array_index_nospec(uref->field_index,
476 field = report->field[uref->field_index];
477 if (uref->usage_index >= field->maxusage)
479 uref->usage_index = array_index_nospec(uref->usage_index,
482 uref->usage_code = field->usage[uref->usage_index].hid;
484 if (copy_to_user(user_arg, uref, sizeof(*uref)))
490 if (cmd != HIDIOCGUSAGE &&
491 cmd != HIDIOCGUSAGES &&
492 uref->report_type == HID_REPORT_TYPE_INPUT)
495 if (uref->report_id == HID_REPORT_ID_UNKNOWN) {
496 field = hiddev_lookup_usage(hid, uref);
500 rinfo.report_type = uref->report_type;
501 rinfo.report_id = uref->report_id;
502 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
505 if (uref->field_index >= report->maxfield)
507 uref->field_index = array_index_nospec(uref->field_index,
510 field = report->field[uref->field_index];
512 if (cmd == HIDIOCGCOLLECTIONINDEX) {
513 if (uref->usage_index >= field->maxusage)
515 } else if (uref->usage_index >= field->report_count)
519 if ((cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) &&
520 (uref_multi->num_values > HID_MAX_MULTI_USAGES ||
521 uref->usage_index + uref_multi->num_values > field->report_count))
526 uref->value = field->value[uref->usage_index];
527 if (copy_to_user(user_arg, uref, sizeof(*uref)))
532 field->value[uref->usage_index] = uref->value;
535 case HIDIOCGCOLLECTIONINDEX:
536 i = field->usage[uref->usage_index].collection_index;
540 for (i = 0; i < uref_multi->num_values; i++)
541 uref_multi->values[i] =
542 field->value[uref->usage_index + i];
543 if (copy_to_user(user_arg, uref_multi,
544 sizeof(*uref_multi)))
548 for (i = 0; i < uref_multi->num_values; i++)
549 field->value[uref->usage_index + i] =
550 uref_multi->values[i];
566 static noinline int hiddev_ioctl_string(struct hiddev *hiddev, unsigned int cmd, void __user *user_arg)
568 struct hid_device *hid = hiddev->hid;
569 struct usb_device *dev = hid_to_usb_dev(hid);
573 if (get_user(idx, (int __user *)user_arg))
576 if ((buf = kmalloc(HID_STRING_SIZE, GFP_KERNEL)) == NULL)
579 if ((len = usb_string(dev, idx, buf, HID_STRING_SIZE-1)) < 0) {
584 if (copy_to_user(user_arg+sizeof(int), buf, len+1)) {
594 static long hiddev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
596 struct hiddev_list *list = file->private_data;
597 struct hiddev *hiddev = list->hiddev;
598 struct hid_device *hid;
599 struct hiddev_collection_info cinfo;
600 struct hiddev_report_info rinfo;
601 struct hiddev_field_info finfo;
602 struct hiddev_devinfo dinfo;
603 struct hid_report *report;
604 struct hid_field *field;
605 void __user *user_arg = (void __user *)arg;
608 /* Called without BKL by compat methods so no BKL taken */
610 mutex_lock(&hiddev->existancelock);
611 if (!hiddev->exist) {
621 r = put_user(HID_VERSION, (int __user *)arg) ?
625 case HIDIOCAPPLICATION:
626 if (arg >= hid->maxapplication)
629 for (i = 0; i < hid->maxcollection; i++)
630 if (hid->collection[i].type ==
631 HID_COLLECTION_APPLICATION && arg-- == 0)
634 if (i < hid->maxcollection)
635 r = hid->collection[i].usage;
640 struct usb_device *dev = hid_to_usb_dev(hid);
641 struct usbhid_device *usbhid = hid->driver_data;
643 memset(&dinfo, 0, sizeof(dinfo));
645 dinfo.bustype = BUS_USB;
646 dinfo.busnum = dev->bus->busnum;
647 dinfo.devnum = dev->devnum;
648 dinfo.ifnum = usbhid->ifnum;
649 dinfo.vendor = le16_to_cpu(dev->descriptor.idVendor);
650 dinfo.product = le16_to_cpu(dev->descriptor.idProduct);
651 dinfo.version = le16_to_cpu(dev->descriptor.bcdDevice);
652 dinfo.num_applications = hid->maxapplication;
654 r = copy_to_user(user_arg, &dinfo, sizeof(dinfo)) ?
660 r = put_user(list->flags, (int __user *)arg) ?
668 if (get_user(newflags, (int __user *)arg)) {
673 if ((newflags & ~HIDDEV_FLAGS) != 0 ||
674 ((newflags & HIDDEV_FLAG_REPORT) != 0 &&
675 (newflags & HIDDEV_FLAG_UREF) == 0))
678 list->flags = newflags;
685 r = hiddev_ioctl_string(hiddev, cmd, user_arg);
688 case HIDIOCINITREPORT:
689 usbhid_init_reports(hid);
690 hiddev->initialized = true;
695 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo))) {
700 if (rinfo.report_type == HID_REPORT_TYPE_OUTPUT)
703 report = hiddev_lookup_report(hid, &rinfo);
707 hid_hw_request(hid, report, HID_REQ_GET_REPORT);
714 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo))) {
719 if (rinfo.report_type == HID_REPORT_TYPE_INPUT)
722 report = hiddev_lookup_report(hid, &rinfo);
726 hid_hw_request(hid, report, HID_REQ_SET_REPORT);
732 case HIDIOCGREPORTINFO:
733 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo))) {
738 report = hiddev_lookup_report(hid, &rinfo);
742 rinfo.num_fields = report->maxfield;
744 r = copy_to_user(user_arg, &rinfo, sizeof(rinfo)) ?
748 case HIDIOCGFIELDINFO:
749 if (copy_from_user(&finfo, user_arg, sizeof(finfo))) {
754 rinfo.report_type = finfo.report_type;
755 rinfo.report_id = finfo.report_id;
757 report = hiddev_lookup_report(hid, &rinfo);
761 if (finfo.field_index >= report->maxfield)
763 finfo.field_index = array_index_nospec(finfo.field_index,
766 field = report->field[finfo.field_index];
767 memset(&finfo, 0, sizeof(finfo));
768 finfo.report_type = rinfo.report_type;
769 finfo.report_id = rinfo.report_id;
770 finfo.field_index = field->report_count - 1;
771 finfo.maxusage = field->maxusage;
772 finfo.flags = field->flags;
773 finfo.physical = field->physical;
774 finfo.logical = field->logical;
775 finfo.application = field->application;
776 finfo.logical_minimum = field->logical_minimum;
777 finfo.logical_maximum = field->logical_maximum;
778 finfo.physical_minimum = field->physical_minimum;
779 finfo.physical_maximum = field->physical_maximum;
780 finfo.unit_exponent = field->unit_exponent;
781 finfo.unit = field->unit;
783 r = copy_to_user(user_arg, &finfo, sizeof(finfo)) ?
793 case HIDIOCGCOLLECTIONINDEX:
794 if (!hiddev->initialized) {
795 usbhid_init_reports(hid);
796 hiddev->initialized = true;
798 r = hiddev_ioctl_usage(hiddev, cmd, user_arg);
801 case HIDIOCGCOLLECTIONINFO:
802 if (copy_from_user(&cinfo, user_arg, sizeof(cinfo))) {
807 if (cinfo.index >= hid->maxcollection)
809 cinfo.index = array_index_nospec(cinfo.index,
812 cinfo.type = hid->collection[cinfo.index].type;
813 cinfo.usage = hid->collection[cinfo.index].usage;
814 cinfo.level = hid->collection[cinfo.index].level;
816 r = copy_to_user(user_arg, &cinfo, sizeof(cinfo)) ?
821 if (_IOC_TYPE(cmd) != 'H' || _IOC_DIR(cmd) != _IOC_READ)
824 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGNAME(0))) {
825 int len = strlen(hid->name) + 1;
826 if (len > _IOC_SIZE(cmd))
827 len = _IOC_SIZE(cmd);
828 r = copy_to_user(user_arg, hid->name, len) ?
833 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGPHYS(0))) {
834 int len = strlen(hid->phys) + 1;
835 if (len > _IOC_SIZE(cmd))
836 len = _IOC_SIZE(cmd);
837 r = copy_to_user(user_arg, hid->phys, len) ?
844 mutex_unlock(&hiddev->existancelock);
849 static long hiddev_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
851 return hiddev_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
855 static const struct file_operations hiddev_fops = {
856 .owner = THIS_MODULE,
858 .write = hiddev_write,
861 .release = hiddev_release,
862 .unlocked_ioctl = hiddev_ioctl,
863 .fasync = hiddev_fasync,
865 .compat_ioctl = hiddev_compat_ioctl,
867 .llseek = noop_llseek,
870 static char *hiddev_devnode(struct device *dev, umode_t *mode)
872 return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev));
875 static struct usb_class_driver hiddev_class = {
877 .devnode = hiddev_devnode,
878 .fops = &hiddev_fops,
879 .minor_base = HIDDEV_MINOR_BASE,
883 * This is where hid.c calls us to connect a hid device to the hiddev driver
885 int hiddev_connect(struct hid_device *hid, unsigned int force)
887 struct hiddev *hiddev;
888 struct usbhid_device *usbhid = hid->driver_data;
893 for (i = 0; i < hid->maxcollection; i++)
894 if (hid->collection[i].type ==
895 HID_COLLECTION_APPLICATION &&
896 !IS_INPUT_APPLICATION(hid->collection[i].usage))
899 if (i == hid->maxcollection)
903 if (!(hiddev = kzalloc(sizeof(struct hiddev), GFP_KERNEL)))
906 init_waitqueue_head(&hiddev->wait);
907 INIT_LIST_HEAD(&hiddev->list);
908 spin_lock_init(&hiddev->list_lock);
909 mutex_init(&hiddev->existancelock);
910 hid->hiddev = hiddev;
913 retval = usb_register_dev(usbhid->intf, &hiddev_class);
915 hid_err(hid, "Not able to get a minor for this device\n");
922 * If HID_QUIRK_NO_INIT_REPORTS is set, make sure we don't initialize
925 hiddev->initialized = hid->quirks & HID_QUIRK_NO_INIT_REPORTS;
927 hiddev->minor = usbhid->intf->minor;
933 * This is where hid.c calls us to disconnect a hiddev device from the
934 * corresponding hid device (usually because the usb device has disconnected)
936 static struct usb_class_driver hiddev_class;
937 void hiddev_disconnect(struct hid_device *hid)
939 struct hiddev *hiddev = hid->hiddev;
940 struct usbhid_device *usbhid = hid->driver_data;
942 usb_deregister_dev(usbhid->intf, &hiddev_class);
944 mutex_lock(&hiddev->existancelock);
948 mutex_unlock(&hiddev->existancelock);
949 hid_hw_close(hiddev->hid);
950 wake_up_interruptible(&hiddev->wait);
952 mutex_unlock(&hiddev->existancelock);