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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * Copyright (c) 2001 Paul Stewart4 * Copyright (c) 2001 Vojtech Pavlik5 *6 * HID char devices, giving access to raw HID device events.7 */8 9/*10 *11 * Should you need to contact me, the author, you can do so either by12 * e-mail - mail your message to Paul Stewart <stewart@wetlogic.net>13 */14 15#include <linux/poll.h>16#include <linux/slab.h>17#include <linux/sched/signal.h>18#include <linux/module.h>19#include <linux/init.h>20#include <linux/input.h>21#include <linux/usb.h>22#include <linux/hid.h>23#include <linux/hiddev.h>24#include <linux/compat.h>25#include <linux/vmalloc.h>26#include <linux/nospec.h>27#include "usbhid.h"28 29#ifdef CONFIG_USB_DYNAMIC_MINORS30#define HIDDEV_MINOR_BASE 031#define HIDDEV_MINORS 25632#else33#define HIDDEV_MINOR_BASE 9634#define HIDDEV_MINORS 1635#endif36#define HIDDEV_BUFFER_SIZE 204837 38struct hiddev_list {39 struct hiddev_usage_ref buffer[HIDDEV_BUFFER_SIZE];40 int head;41 int tail;42 unsigned flags;43 struct fasync_struct *fasync;44 struct hiddev *hiddev;45 struct list_head node;46 struct mutex thread_lock;47};48 49/*50 * Find a report, given the report's type and ID. The ID can be specified51 * indirectly by REPORT_ID_FIRST (which returns the first report of the given52 * type) or by (REPORT_ID_NEXT | old_id), which returns the next report of the53 * given type which follows old_id.54 */55static struct hid_report *56hiddev_lookup_report(struct hid_device *hid, struct hiddev_report_info *rinfo)57{58 unsigned int flags = rinfo->report_id & ~HID_REPORT_ID_MASK;59 unsigned int rid = rinfo->report_id & HID_REPORT_ID_MASK;60 struct hid_report_enum *report_enum;61 struct hid_report *report;62 struct list_head *list;63 64 if (rinfo->report_type < HID_REPORT_TYPE_MIN ||65 rinfo->report_type > HID_REPORT_TYPE_MAX)66 return NULL;67 68 report_enum = hid->report_enum +69 (rinfo->report_type - HID_REPORT_TYPE_MIN);70 71 switch (flags) {72 case 0: /* Nothing to do -- report_id is already set correctly */73 break;74 75 case HID_REPORT_ID_FIRST:76 if (list_empty(&report_enum->report_list))77 return NULL;78 79 list = report_enum->report_list.next;80 report = list_entry(list, struct hid_report, list);81 rinfo->report_id = report->id;82 break;83 84 case HID_REPORT_ID_NEXT:85 report = report_enum->report_id_hash[rid];86 if (!report)87 return NULL;88 89 list = report->list.next;90 if (list == &report_enum->report_list)91 return NULL;92 93 report = list_entry(list, struct hid_report, list);94 rinfo->report_id = report->id;95 break;96 97 default:98 return NULL;99 }100 101 return report_enum->report_id_hash[rinfo->report_id];102}103 104/*105 * Perform an exhaustive search of the report table for a usage, given its106 * type and usage id.107 */108static struct hid_field *109hiddev_lookup_usage(struct hid_device *hid, struct hiddev_usage_ref *uref)110{111 int i, j;112 struct hid_report *report;113 struct hid_report_enum *report_enum;114 struct hid_field *field;115 116 if (uref->report_type < HID_REPORT_TYPE_MIN ||117 uref->report_type > HID_REPORT_TYPE_MAX)118 return NULL;119 120 report_enum = hid->report_enum +121 (uref->report_type - HID_REPORT_TYPE_MIN);122 123 list_for_each_entry(report, &report_enum->report_list, list) {124 for (i = 0; i < report->maxfield; i++) {125 field = report->field[i];126 for (j = 0; j < field->maxusage; j++) {127 if (field->usage[j].hid == uref->usage_code) {128 uref->report_id = report->id;129 uref->field_index = i;130 uref->usage_index = j;131 return field;132 }133 }134 }135 }136 137 return NULL;138}139 140static void hiddev_send_event(struct hid_device *hid,141 struct hiddev_usage_ref *uref)142{143 struct hiddev *hiddev = hid->hiddev;144 struct hiddev_list *list;145 unsigned long flags;146 147 spin_lock_irqsave(&hiddev->list_lock, flags);148 list_for_each_entry(list, &hiddev->list, node) {149 if (uref->field_index != HID_FIELD_INDEX_NONE ||150 (list->flags & HIDDEV_FLAG_REPORT) != 0) {151 list->buffer[list->head] = *uref;152 list->head = (list->head + 1) &153 (HIDDEV_BUFFER_SIZE - 1);154 kill_fasync(&list->fasync, SIGIO, POLL_IN);155 }156 }157 spin_unlock_irqrestore(&hiddev->list_lock, flags);158 159 wake_up_interruptible(&hiddev->wait);160}161 162/*163 * This is where hid.c calls into hiddev to pass an event that occurred over164 * the interrupt pipe165 */166void hiddev_hid_event(struct hid_device *hid, struct hid_field *field,167 struct hid_usage *usage, __s32 value)168{169 unsigned type = field->report_type;170 struct hiddev_usage_ref uref;171 172 uref.report_type =173 (type == HID_INPUT_REPORT) ? HID_REPORT_TYPE_INPUT :174 ((type == HID_OUTPUT_REPORT) ? HID_REPORT_TYPE_OUTPUT :175 ((type == HID_FEATURE_REPORT) ? HID_REPORT_TYPE_FEATURE : 0));176 uref.report_id = field->report->id;177 uref.field_index = field->index;178 uref.usage_index = (usage - field->usage);179 uref.usage_code = usage->hid;180 uref.value = value;181 182 hiddev_send_event(hid, &uref);183}184EXPORT_SYMBOL_GPL(hiddev_hid_event);185 186void hiddev_report_event(struct hid_device *hid, struct hid_report *report)187{188 unsigned type = report->type;189 struct hiddev_usage_ref uref;190 191 memset(&uref, 0, sizeof(uref));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 = report->id;197 uref.field_index = HID_FIELD_INDEX_NONE;198 199 hiddev_send_event(hid, &uref);200}201 202/*203 * fasync file op204 */205static int hiddev_fasync(int fd, struct file *file, int on)206{207 struct hiddev_list *list = file->private_data;208 209 return fasync_helper(fd, file, on, &list->fasync);210}211 212 213/*214 * release file op215 */216static int hiddev_release(struct inode * inode, struct file * file)217{218 struct hiddev_list *list = file->private_data;219 unsigned long flags;220 221 spin_lock_irqsave(&list->hiddev->list_lock, flags);222 list_del(&list->node);223 spin_unlock_irqrestore(&list->hiddev->list_lock, flags);224 225 mutex_lock(&list->hiddev->existancelock);226 if (!--list->hiddev->open) {227 if (list->hiddev->exist) {228 hid_hw_close(list->hiddev->hid);229 hid_hw_power(list->hiddev->hid, PM_HINT_NORMAL);230 } else {231 mutex_unlock(&list->hiddev->existancelock);232 kfree(list->hiddev);233 vfree(list);234 return 0;235 }236 }237 238 mutex_unlock(&list->hiddev->existancelock);239 vfree(list);240 241 return 0;242}243 244static int __hiddev_open(struct hiddev *hiddev, struct file *file)245{246 struct hiddev_list *list;247 int error;248 249 lockdep_assert_held(&hiddev->existancelock);250 251 list = vzalloc(sizeof(*list));252 if (!list)253 return -ENOMEM;254 255 mutex_init(&list->thread_lock);256 list->hiddev = hiddev;257 258 if (!hiddev->open++) {259 error = hid_hw_power(hiddev->hid, PM_HINT_FULLON);260 if (error < 0)261 goto err_drop_count;262 263 error = hid_hw_open(hiddev->hid);264 if (error < 0)265 goto err_normal_power;266 }267 268 spin_lock_irq(&hiddev->list_lock);269 list_add_tail(&list->node, &hiddev->list);270 spin_unlock_irq(&hiddev->list_lock);271 272 file->private_data = list;273 274 return 0;275 276err_normal_power:277 hid_hw_power(hiddev->hid, PM_HINT_NORMAL);278err_drop_count:279 hiddev->open--;280 vfree(list);281 return error;282}283 284/*285 * open file op286 */287static int hiddev_open(struct inode *inode, struct file *file)288{289 struct usb_interface *intf;290 struct hid_device *hid;291 struct hiddev *hiddev;292 int res;293 294 intf = usbhid_find_interface(iminor(inode));295 if (!intf)296 return -ENODEV;297 298 hid = usb_get_intfdata(intf);299 hiddev = hid->hiddev;300 301 mutex_lock(&hiddev->existancelock);302 res = hiddev->exist ? __hiddev_open(hiddev, file) : -ENODEV;303 mutex_unlock(&hiddev->existancelock);304 305 return res;306}307 308/*309 * "write" file op310 */311static ssize_t hiddev_write(struct file * file, const char __user * buffer, size_t count, loff_t *ppos)312{313 return -EINVAL;314}315 316/*317 * "read" file op318 */319static ssize_t hiddev_read(struct file * file, char __user * buffer, size_t count, loff_t *ppos)320{321 DEFINE_WAIT(wait);322 struct hiddev_list *list = file->private_data;323 int event_size;324 int retval;325 326 event_size = ((list->flags & HIDDEV_FLAG_UREF) != 0) ?327 sizeof(struct hiddev_usage_ref) : sizeof(struct hiddev_event);328 329 if (count < event_size)330 return 0;331 332 /* lock against other threads */333 retval = mutex_lock_interruptible(&list->thread_lock);334 if (retval)335 return -ERESTARTSYS;336 337 while (retval == 0) {338 if (list->head == list->tail) {339 prepare_to_wait(&list->hiddev->wait, &wait, TASK_INTERRUPTIBLE);340 341 while (list->head == list->tail) {342 if (signal_pending(current)) {343 retval = -ERESTARTSYS;344 break;345 }346 if (!list->hiddev->exist) {347 retval = -EIO;348 break;349 }350 if (file->f_flags & O_NONBLOCK) {351 retval = -EAGAIN;352 break;353 }354 355 /* let O_NONBLOCK tasks run */356 mutex_unlock(&list->thread_lock);357 schedule();358 if (mutex_lock_interruptible(&list->thread_lock)) {359 finish_wait(&list->hiddev->wait, &wait);360 return -EINTR;361 }362 set_current_state(TASK_INTERRUPTIBLE);363 }364 finish_wait(&list->hiddev->wait, &wait);365 366 }367 368 if (retval) {369 mutex_unlock(&list->thread_lock);370 return retval;371 }372 373 374 while (list->head != list->tail &&375 retval + event_size <= count) {376 if ((list->flags & HIDDEV_FLAG_UREF) == 0) {377 if (list->buffer[list->tail].field_index != HID_FIELD_INDEX_NONE) {378 struct hiddev_event event;379 380 event.hid = list->buffer[list->tail].usage_code;381 event.value = list->buffer[list->tail].value;382 if (copy_to_user(buffer + retval, &event, sizeof(struct hiddev_event))) {383 mutex_unlock(&list->thread_lock);384 return -EFAULT;385 }386 retval += sizeof(struct hiddev_event);387 }388 } else {389 if (list->buffer[list->tail].field_index != HID_FIELD_INDEX_NONE ||390 (list->flags & HIDDEV_FLAG_REPORT) != 0) {391 392 if (copy_to_user(buffer + retval, list->buffer + list->tail, sizeof(struct hiddev_usage_ref))) {393 mutex_unlock(&list->thread_lock);394 return -EFAULT;395 }396 retval += sizeof(struct hiddev_usage_ref);397 }398 }399 list->tail = (list->tail + 1) & (HIDDEV_BUFFER_SIZE - 1);400 }401 402 }403 mutex_unlock(&list->thread_lock);404 405 return retval;406}407 408/*409 * "poll" file op410 * No kernel lock - fine411 */412static __poll_t hiddev_poll(struct file *file, poll_table *wait)413{414 struct hiddev_list *list = file->private_data;415 416 poll_wait(file, &list->hiddev->wait, wait);417 if (list->head != list->tail)418 return EPOLLIN | EPOLLRDNORM | EPOLLOUT;419 if (!list->hiddev->exist)420 return EPOLLERR | EPOLLHUP;421 return 0;422}423 424/*425 * "ioctl" file op426 */427static noinline int hiddev_ioctl_usage(struct hiddev *hiddev, unsigned int cmd, void __user *user_arg)428{429 struct hid_device *hid = hiddev->hid;430 struct hiddev_report_info rinfo;431 struct hiddev_usage_ref_multi *uref_multi = NULL;432 struct hiddev_usage_ref *uref;433 struct hid_report *report;434 struct hid_field *field;435 int i;436 437 uref_multi = kmalloc(sizeof(struct hiddev_usage_ref_multi), GFP_KERNEL);438 if (!uref_multi)439 return -ENOMEM;440 uref = &uref_multi->uref;441 if (cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) {442 if (copy_from_user(uref_multi, user_arg,443 sizeof(*uref_multi)))444 goto fault;445 } else {446 if (copy_from_user(uref, user_arg, sizeof(*uref)))447 goto fault;448 }449 450 switch (cmd) {451 case HIDIOCGUCODE:452 rinfo.report_type = uref->report_type;453 rinfo.report_id = uref->report_id;454 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)455 goto inval;456 457 if (uref->field_index >= report->maxfield)458 goto inval;459 uref->field_index = array_index_nospec(uref->field_index,460 report->maxfield);461 462 field = report->field[uref->field_index];463 if (uref->usage_index >= field->maxusage)464 goto inval;465 uref->usage_index = array_index_nospec(uref->usage_index,466 field->maxusage);467 468 uref->usage_code = field->usage[uref->usage_index].hid;469 470 if (copy_to_user(user_arg, uref, sizeof(*uref)))471 goto fault;472 473 goto goodreturn;474 475 default:476 if (cmd != HIDIOCGUSAGE &&477 cmd != HIDIOCGUSAGES &&478 uref->report_type == HID_REPORT_TYPE_INPUT)479 goto inval;480 481 if (uref->report_id == HID_REPORT_ID_UNKNOWN) {482 field = hiddev_lookup_usage(hid, uref);483 if (field == NULL)484 goto inval;485 } else {486 rinfo.report_type = uref->report_type;487 rinfo.report_id = uref->report_id;488 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)489 goto inval;490 491 if (uref->field_index >= report->maxfield)492 goto inval;493 uref->field_index = array_index_nospec(uref->field_index,494 report->maxfield);495 496 field = report->field[uref->field_index];497 498 if (cmd == HIDIOCGCOLLECTIONINDEX) {499 if (uref->usage_index >= field->maxusage)500 goto inval;501 uref->usage_index =502 array_index_nospec(uref->usage_index,503 field->maxusage);504 } else if (uref->usage_index >= field->report_count)505 goto inval;506 }507 508 if (cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) {509 if (uref_multi->num_values > HID_MAX_MULTI_USAGES ||510 uref->usage_index + uref_multi->num_values >511 field->report_count)512 goto inval;513 514 uref->usage_index =515 array_index_nospec(uref->usage_index,516 field->report_count -517 uref_multi->num_values);518 }519 520 switch (cmd) {521 case HIDIOCGUSAGE:522 if (uref->usage_index >= field->report_count)523 goto inval;524 uref->value = field->value[uref->usage_index];525 if (copy_to_user(user_arg, uref, sizeof(*uref)))526 goto fault;527 goto goodreturn;528 529 case HIDIOCSUSAGE:530 if (uref->usage_index >= field->report_count)531 goto inval;532 field->value[uref->usage_index] = uref->value;533 goto goodreturn;534 535 case HIDIOCGCOLLECTIONINDEX:536 i = field->usage[uref->usage_index].collection_index;537 kfree(uref_multi);538 return i;539 case HIDIOCGUSAGES: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)))545 goto fault;546 goto goodreturn;547 case HIDIOCSUSAGES:548 for (i = 0; i < uref_multi->num_values; i++)549 field->value[uref->usage_index + i] =550 uref_multi->values[i];551 goto goodreturn;552 }553 554goodreturn:555 kfree(uref_multi);556 return 0;557fault:558 kfree(uref_multi);559 return -EFAULT;560inval:561 kfree(uref_multi);562 return -EINVAL;563 }564}565 566static noinline int hiddev_ioctl_string(struct hiddev *hiddev, unsigned int cmd, void __user *user_arg)567{568 struct hid_device *hid = hiddev->hid;569 struct usb_device *dev = hid_to_usb_dev(hid);570 int idx, len;571 char *buf;572 573 if (get_user(idx, (int __user *)user_arg))574 return -EFAULT;575 576 if ((buf = kmalloc(HID_STRING_SIZE, GFP_KERNEL)) == NULL)577 return -ENOMEM;578 579 if ((len = usb_string(dev, idx, buf, HID_STRING_SIZE-1)) < 0) {580 kfree(buf);581 return -EINVAL;582 }583 584 if (copy_to_user(user_arg+sizeof(int), buf, len+1)) {585 kfree(buf);586 return -EFAULT;587 }588 589 kfree(buf);590 591 return len;592}593 594static long hiddev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)595{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;606 int i, r = -EINVAL;607 608 /* Called without BKL by compat methods so no BKL taken */609 610 mutex_lock(&hiddev->existancelock);611 if (!hiddev->exist) {612 r = -ENODEV;613 goto ret_unlock;614 }615 616 hid = hiddev->hid;617 618 switch (cmd) {619 620 case HIDIOCGVERSION:621 r = put_user(HID_VERSION, (int __user *)arg) ?622 -EFAULT : 0;623 break;624 625 case HIDIOCAPPLICATION:626 if (arg >= hid->maxapplication)627 break;628 629 for (i = 0; i < hid->maxcollection; i++)630 if (hid->collection[i].type ==631 HID_COLLECTION_APPLICATION && arg-- == 0)632 break;633 634 if (i < hid->maxcollection)635 r = hid->collection[i].usage;636 break;637 638 case HIDIOCGDEVINFO:639 {640 struct usb_device *dev = hid_to_usb_dev(hid);641 struct usbhid_device *usbhid = hid->driver_data;642 643 memset(&dinfo, 0, sizeof(dinfo));644 645 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;653 654 r = copy_to_user(user_arg, &dinfo, sizeof(dinfo)) ?655 -EFAULT : 0;656 break;657 }658 659 case HIDIOCGFLAG:660 r = put_user(list->flags, (int __user *)arg) ?661 -EFAULT : 0;662 break;663 664 case HIDIOCSFLAG:665 {666 int newflags;667 668 if (get_user(newflags, (int __user *)arg)) {669 r = -EFAULT;670 break;671 }672 673 if ((newflags & ~HIDDEV_FLAGS) != 0 ||674 ((newflags & HIDDEV_FLAG_REPORT) != 0 &&675 (newflags & HIDDEV_FLAG_UREF) == 0))676 break;677 678 list->flags = newflags;679 680 r = 0;681 break;682 }683 684 case HIDIOCGSTRING:685 r = hiddev_ioctl_string(hiddev, cmd, user_arg);686 break;687 688 case HIDIOCINITREPORT:689 usbhid_init_reports(hid);690 hiddev->initialized = true;691 r = 0;692 break;693 694 case HIDIOCGREPORT:695 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo))) {696 r = -EFAULT;697 break;698 }699 700 if (rinfo.report_type == HID_REPORT_TYPE_OUTPUT)701 break;702 703 report = hiddev_lookup_report(hid, &rinfo);704 if (report == NULL)705 break;706 707 hid_hw_request(hid, report, HID_REQ_GET_REPORT);708 hid_hw_wait(hid);709 710 r = 0;711 break;712 713 case HIDIOCSREPORT:714 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo))) {715 r = -EFAULT;716 break;717 }718 719 if (rinfo.report_type == HID_REPORT_TYPE_INPUT)720 break;721 722 report = hiddev_lookup_report(hid, &rinfo);723 if (report == NULL)724 break;725 726 hid_hw_request(hid, report, HID_REQ_SET_REPORT);727 hid_hw_wait(hid);728 729 r = 0;730 break;731 732 case HIDIOCGREPORTINFO:733 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo))) {734 r = -EFAULT;735 break;736 }737 738 report = hiddev_lookup_report(hid, &rinfo);739 if (report == NULL)740 break;741 742 rinfo.num_fields = report->maxfield;743 744 r = copy_to_user(user_arg, &rinfo, sizeof(rinfo)) ?745 -EFAULT : 0;746 break;747 748 case HIDIOCGFIELDINFO:749 if (copy_from_user(&finfo, user_arg, sizeof(finfo))) {750 r = -EFAULT;751 break;752 }753 754 rinfo.report_type = finfo.report_type;755 rinfo.report_id = finfo.report_id;756 757 report = hiddev_lookup_report(hid, &rinfo);758 if (report == NULL)759 break;760 761 if (finfo.field_index >= report->maxfield)762 break;763 finfo.field_index = array_index_nospec(finfo.field_index,764 report->maxfield);765 766 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;782 783 r = copy_to_user(user_arg, &finfo, sizeof(finfo)) ?784 -EFAULT : 0;785 break;786 787 case HIDIOCGUCODE:788 case HIDIOCGUSAGE:789 case HIDIOCSUSAGE:790 case HIDIOCGUSAGES:791 case HIDIOCSUSAGES:792 case HIDIOCGCOLLECTIONINDEX:793 if (!hiddev->initialized) {794 usbhid_init_reports(hid);795 hiddev->initialized = true;796 }797 r = hiddev_ioctl_usage(hiddev, cmd, user_arg);798 break;799 800 case HIDIOCGCOLLECTIONINFO:801 if (copy_from_user(&cinfo, user_arg, sizeof(cinfo))) {802 r = -EFAULT;803 break;804 }805 806 if (cinfo.index >= hid->maxcollection)807 break;808 cinfo.index = array_index_nospec(cinfo.index,809 hid->maxcollection);810 811 cinfo.type = hid->collection[cinfo.index].type;812 cinfo.usage = hid->collection[cinfo.index].usage;813 cinfo.level = hid->collection[cinfo.index].level;814 815 r = copy_to_user(user_arg, &cinfo, sizeof(cinfo)) ?816 -EFAULT : 0;817 break;818 819 default:820 if (_IOC_TYPE(cmd) != 'H' || _IOC_DIR(cmd) != _IOC_READ)821 break;822 823 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGNAME(0))) {824 int len = strlen(hid->name) + 1;825 if (len > _IOC_SIZE(cmd))826 len = _IOC_SIZE(cmd);827 r = copy_to_user(user_arg, hid->name, len) ?828 -EFAULT : len;829 break;830 }831 832 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGPHYS(0))) {833 int len = strlen(hid->phys) + 1;834 if (len > _IOC_SIZE(cmd))835 len = _IOC_SIZE(cmd);836 r = copy_to_user(user_arg, hid->phys, len) ?837 -EFAULT : len;838 break;839 }840 }841 842ret_unlock:843 mutex_unlock(&hiddev->existancelock);844 return r;845}846 847static const struct file_operations hiddev_fops = {848 .owner = THIS_MODULE,849 .read = hiddev_read,850 .write = hiddev_write,851 .poll = hiddev_poll,852 .open = hiddev_open,853 .release = hiddev_release,854 .unlocked_ioctl = hiddev_ioctl,855 .fasync = hiddev_fasync,856 .compat_ioctl = compat_ptr_ioctl,857 .llseek = noop_llseek,858};859 860static char *hiddev_devnode(const struct device *dev, umode_t *mode)861{862 return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev));863}864 865static struct usb_class_driver hiddev_class = {866 .name = "hiddev%d",867 .devnode = hiddev_devnode,868 .fops = &hiddev_fops,869 .minor_base = HIDDEV_MINOR_BASE,870};871 872/*873 * This is where hid.c calls us to connect a hid device to the hiddev driver874 */875int hiddev_connect(struct hid_device *hid, unsigned int force)876{877 struct hiddev *hiddev;878 struct usbhid_device *usbhid = hid->driver_data;879 int retval;880 881 if (!force) {882 unsigned int i;883 for (i = 0; i < hid->maxcollection; i++)884 if (hid->collection[i].type ==885 HID_COLLECTION_APPLICATION &&886 !IS_INPUT_APPLICATION(hid->collection[i].usage))887 break;888 889 if (i == hid->maxcollection)890 return -EINVAL;891 }892 893 if (!(hiddev = kzalloc(sizeof(struct hiddev), GFP_KERNEL)))894 return -ENOMEM;895 896 init_waitqueue_head(&hiddev->wait);897 INIT_LIST_HEAD(&hiddev->list);898 spin_lock_init(&hiddev->list_lock);899 mutex_init(&hiddev->existancelock);900 hid->hiddev = hiddev;901 hiddev->hid = hid;902 hiddev->exist = 1;903 retval = usb_register_dev(usbhid->intf, &hiddev_class);904 if (retval) {905 hid_err(hid, "Not able to get a minor for this device\n");906 hid->hiddev = NULL;907 kfree(hiddev);908 return retval;909 }910 911 /*912 * If HID_QUIRK_NO_INIT_REPORTS is set, make sure we don't initialize913 * the reports.914 */915 hiddev->initialized = hid->quirks & HID_QUIRK_NO_INIT_REPORTS;916 917 hiddev->minor = usbhid->intf->minor;918 919 return 0;920}921 922/*923 * This is where hid.c calls us to disconnect a hiddev device from the924 * corresponding hid device (usually because the usb device has disconnected)925 */926static struct usb_class_driver hiddev_class;927void hiddev_disconnect(struct hid_device *hid)928{929 struct hiddev *hiddev = hid->hiddev;930 struct usbhid_device *usbhid = hid->driver_data;931 932 usb_deregister_dev(usbhid->intf, &hiddev_class);933 934 mutex_lock(&hiddev->existancelock);935 hiddev->exist = 0;936 937 if (hiddev->open) {938 hid_hw_close(hiddev->hid);939 wake_up_interruptible(&hiddev->wait);940 mutex_unlock(&hiddev->existancelock);941 } else {942 mutex_unlock(&hiddev->existancelock);943 kfree(hiddev);944 }945}946