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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * User-space I/O driver support for HID subsystem4 * Copyright (c) 2012 David Herrmann5 */6 7/*8 */9 10#include <linux/atomic.h>11#include <linux/compat.h>12#include <linux/cred.h>13#include <linux/device.h>14#include <linux/fs.h>15#include <linux/hid.h>16#include <linux/input.h>17#include <linux/miscdevice.h>18#include <linux/module.h>19#include <linux/mutex.h>20#include <linux/poll.h>21#include <linux/sched.h>22#include <linux/spinlock.h>23#include <linux/uhid.h>24#include <linux/wait.h>25 26#define UHID_NAME "uhid"27#define UHID_BUFSIZE 3228 29struct uhid_device {30 struct mutex devlock;31 32 /* This flag tracks whether the HID device is usable for commands from33 * userspace. The flag is already set before hid_add_device(), which34 * runs in workqueue context, to allow hid_add_device() to communicate35 * with userspace.36 * However, if hid_add_device() fails, the flag is cleared without37 * holding devlock.38 * We guarantee that if @running changes from true to false while you're39 * holding @devlock, it's still fine to access @hid.40 */41 bool running;42 43 __u8 *rd_data;44 uint rd_size;45 46 /* When this is NULL, userspace may use UHID_CREATE/UHID_CREATE2. */47 struct hid_device *hid;48 struct uhid_event input_buf;49 50 wait_queue_head_t waitq;51 spinlock_t qlock;52 __u8 head;53 __u8 tail;54 struct uhid_event *outq[UHID_BUFSIZE];55 56 /* blocking GET_REPORT support; state changes protected by qlock */57 struct mutex report_lock;58 wait_queue_head_t report_wait;59 bool report_running;60 u32 report_id;61 u32 report_type;62 struct uhid_event report_buf;63 struct work_struct worker;64};65 66static struct miscdevice uhid_misc;67 68static void uhid_device_add_worker(struct work_struct *work)69{70 struct uhid_device *uhid = container_of(work, struct uhid_device, worker);71 int ret;72 73 ret = hid_add_device(uhid->hid);74 if (ret) {75 hid_err(uhid->hid, "Cannot register HID device: error %d\n", ret);76 77 /* We used to call hid_destroy_device() here, but that's really78 * messy to get right because we have to coordinate with79 * concurrent writes from userspace that might be in the middle80 * of using uhid->hid.81 * Just leave uhid->hid as-is for now, and clean it up when82 * userspace tries to close or reinitialize the uhid instance.83 *84 * However, we do have to clear the ->running flag and do a85 * wakeup to make sure userspace knows that the device is gone.86 */87 WRITE_ONCE(uhid->running, false);88 wake_up_interruptible(&uhid->report_wait);89 }90}91 92static void uhid_queue(struct uhid_device *uhid, struct uhid_event *ev)93{94 __u8 newhead;95 96 newhead = (uhid->head + 1) % UHID_BUFSIZE;97 98 if (newhead != uhid->tail) {99 uhid->outq[uhid->head] = ev;100 uhid->head = newhead;101 wake_up_interruptible(&uhid->waitq);102 } else {103 hid_warn(uhid->hid, "Output queue is full\n");104 kfree(ev);105 }106}107 108static int uhid_queue_event(struct uhid_device *uhid, __u32 event)109{110 unsigned long flags;111 struct uhid_event *ev;112 113 ev = kzalloc(sizeof(*ev), GFP_KERNEL);114 if (!ev)115 return -ENOMEM;116 117 ev->type = event;118 119 spin_lock_irqsave(&uhid->qlock, flags);120 uhid_queue(uhid, ev);121 spin_unlock_irqrestore(&uhid->qlock, flags);122 123 return 0;124}125 126static int uhid_hid_start(struct hid_device *hid)127{128 struct uhid_device *uhid = hid->driver_data;129 struct uhid_event *ev;130 unsigned long flags;131 132 ev = kzalloc(sizeof(*ev), GFP_KERNEL);133 if (!ev)134 return -ENOMEM;135 136 ev->type = UHID_START;137 138 if (hid->report_enum[HID_FEATURE_REPORT].numbered)139 ev->u.start.dev_flags |= UHID_DEV_NUMBERED_FEATURE_REPORTS;140 if (hid->report_enum[HID_OUTPUT_REPORT].numbered)141 ev->u.start.dev_flags |= UHID_DEV_NUMBERED_OUTPUT_REPORTS;142 if (hid->report_enum[HID_INPUT_REPORT].numbered)143 ev->u.start.dev_flags |= UHID_DEV_NUMBERED_INPUT_REPORTS;144 145 spin_lock_irqsave(&uhid->qlock, flags);146 uhid_queue(uhid, ev);147 spin_unlock_irqrestore(&uhid->qlock, flags);148 149 return 0;150}151 152static void uhid_hid_stop(struct hid_device *hid)153{154 struct uhid_device *uhid = hid->driver_data;155 156 hid->claimed = 0;157 uhid_queue_event(uhid, UHID_STOP);158}159 160static int uhid_hid_open(struct hid_device *hid)161{162 struct uhid_device *uhid = hid->driver_data;163 164 return uhid_queue_event(uhid, UHID_OPEN);165}166 167static void uhid_hid_close(struct hid_device *hid)168{169 struct uhid_device *uhid = hid->driver_data;170 171 uhid_queue_event(uhid, UHID_CLOSE);172}173 174static int uhid_hid_parse(struct hid_device *hid)175{176 struct uhid_device *uhid = hid->driver_data;177 178 return hid_parse_report(hid, uhid->rd_data, uhid->rd_size);179}180 181/* must be called with report_lock held */182static int __uhid_report_queue_and_wait(struct uhid_device *uhid,183 struct uhid_event *ev,184 __u32 *report_id)185{186 unsigned long flags;187 int ret;188 189 spin_lock_irqsave(&uhid->qlock, flags);190 *report_id = ++uhid->report_id;191 uhid->report_type = ev->type + 1;192 uhid->report_running = true;193 uhid_queue(uhid, ev);194 spin_unlock_irqrestore(&uhid->qlock, flags);195 196 ret = wait_event_interruptible_timeout(uhid->report_wait,197 !uhid->report_running || !READ_ONCE(uhid->running),198 5 * HZ);199 if (!ret || !READ_ONCE(uhid->running) || uhid->report_running)200 ret = -EIO;201 else if (ret < 0)202 ret = -ERESTARTSYS;203 else204 ret = 0;205 206 uhid->report_running = false;207 208 return ret;209}210 211static void uhid_report_wake_up(struct uhid_device *uhid, u32 id,212 const struct uhid_event *ev)213{214 unsigned long flags;215 216 spin_lock_irqsave(&uhid->qlock, flags);217 218 /* id for old report; drop it silently */219 if (uhid->report_type != ev->type || uhid->report_id != id)220 goto unlock;221 if (!uhid->report_running)222 goto unlock;223 224 memcpy(&uhid->report_buf, ev, sizeof(*ev));225 uhid->report_running = false;226 wake_up_interruptible(&uhid->report_wait);227 228unlock:229 spin_unlock_irqrestore(&uhid->qlock, flags);230}231 232static int uhid_hid_get_report(struct hid_device *hid, unsigned char rnum,233 u8 *buf, size_t count, u8 rtype)234{235 struct uhid_device *uhid = hid->driver_data;236 struct uhid_get_report_reply_req *req;237 struct uhid_event *ev;238 int ret;239 240 if (!READ_ONCE(uhid->running))241 return -EIO;242 243 ev = kzalloc(sizeof(*ev), GFP_KERNEL);244 if (!ev)245 return -ENOMEM;246 247 ev->type = UHID_GET_REPORT;248 ev->u.get_report.rnum = rnum;249 ev->u.get_report.rtype = rtype;250 251 ret = mutex_lock_interruptible(&uhid->report_lock);252 if (ret) {253 kfree(ev);254 return ret;255 }256 257 /* this _always_ takes ownership of @ev */258 ret = __uhid_report_queue_and_wait(uhid, ev, &ev->u.get_report.id);259 if (ret)260 goto unlock;261 262 req = &uhid->report_buf.u.get_report_reply;263 if (req->err) {264 ret = -EIO;265 } else {266 ret = min3(count, (size_t)req->size, (size_t)UHID_DATA_MAX);267 memcpy(buf, req->data, ret);268 }269 270unlock:271 mutex_unlock(&uhid->report_lock);272 return ret;273}274 275static int uhid_hid_set_report(struct hid_device *hid, unsigned char rnum,276 const u8 *buf, size_t count, u8 rtype)277{278 struct uhid_device *uhid = hid->driver_data;279 struct uhid_event *ev;280 int ret;281 282 if (!READ_ONCE(uhid->running) || count > UHID_DATA_MAX)283 return -EIO;284 285 ev = kzalloc(sizeof(*ev), GFP_KERNEL);286 if (!ev)287 return -ENOMEM;288 289 ev->type = UHID_SET_REPORT;290 ev->u.set_report.rnum = rnum;291 ev->u.set_report.rtype = rtype;292 ev->u.set_report.size = count;293 memcpy(ev->u.set_report.data, buf, count);294 295 ret = mutex_lock_interruptible(&uhid->report_lock);296 if (ret) {297 kfree(ev);298 return ret;299 }300 301 /* this _always_ takes ownership of @ev */302 ret = __uhid_report_queue_and_wait(uhid, ev, &ev->u.set_report.id);303 if (ret)304 goto unlock;305 306 if (uhid->report_buf.u.set_report_reply.err)307 ret = -EIO;308 else309 ret = count;310 311unlock:312 mutex_unlock(&uhid->report_lock);313 return ret;314}315 316static int uhid_hid_raw_request(struct hid_device *hid, unsigned char reportnum,317 __u8 *buf, size_t len, unsigned char rtype,318 int reqtype)319{320 u8 u_rtype;321 322 switch (rtype) {323 case HID_FEATURE_REPORT:324 u_rtype = UHID_FEATURE_REPORT;325 break;326 case HID_OUTPUT_REPORT:327 u_rtype = UHID_OUTPUT_REPORT;328 break;329 case HID_INPUT_REPORT:330 u_rtype = UHID_INPUT_REPORT;331 break;332 default:333 return -EINVAL;334 }335 336 switch (reqtype) {337 case HID_REQ_GET_REPORT:338 return uhid_hid_get_report(hid, reportnum, buf, len, u_rtype);339 case HID_REQ_SET_REPORT:340 return uhid_hid_set_report(hid, reportnum, buf, len, u_rtype);341 default:342 return -EIO;343 }344}345 346static int uhid_hid_output_raw(struct hid_device *hid, __u8 *buf, size_t count,347 unsigned char report_type)348{349 struct uhid_device *uhid = hid->driver_data;350 __u8 rtype;351 unsigned long flags;352 struct uhid_event *ev;353 354 switch (report_type) {355 case HID_FEATURE_REPORT:356 rtype = UHID_FEATURE_REPORT;357 break;358 case HID_OUTPUT_REPORT:359 rtype = UHID_OUTPUT_REPORT;360 break;361 default:362 return -EINVAL;363 }364 365 if (count < 1 || count > UHID_DATA_MAX)366 return -EINVAL;367 368 ev = kzalloc(sizeof(*ev), GFP_KERNEL);369 if (!ev)370 return -ENOMEM;371 372 ev->type = UHID_OUTPUT;373 ev->u.output.size = count;374 ev->u.output.rtype = rtype;375 memcpy(ev->u.output.data, buf, count);376 377 spin_lock_irqsave(&uhid->qlock, flags);378 uhid_queue(uhid, ev);379 spin_unlock_irqrestore(&uhid->qlock, flags);380 381 return count;382}383 384static int uhid_hid_output_report(struct hid_device *hid, __u8 *buf,385 size_t count)386{387 return uhid_hid_output_raw(hid, buf, count, HID_OUTPUT_REPORT);388}389 390static const struct hid_ll_driver uhid_hid_driver = {391 .start = uhid_hid_start,392 .stop = uhid_hid_stop,393 .open = uhid_hid_open,394 .close = uhid_hid_close,395 .parse = uhid_hid_parse,396 .raw_request = uhid_hid_raw_request,397 .output_report = uhid_hid_output_report,398 .max_buffer_size = UHID_DATA_MAX,399};400 401#ifdef CONFIG_COMPAT402 403/* Apparently we haven't stepped on these rakes enough times yet. */404struct uhid_create_req_compat {405 __u8 name[128];406 __u8 phys[64];407 __u8 uniq[64];408 409 compat_uptr_t rd_data;410 __u16 rd_size;411 412 __u16 bus;413 __u32 vendor;414 __u32 product;415 __u32 version;416 __u32 country;417} __attribute__((__packed__));418 419static int uhid_event_from_user(const char __user *buffer, size_t len,420 struct uhid_event *event)421{422 if (in_compat_syscall()) {423 u32 type;424 425 if (get_user(type, buffer))426 return -EFAULT;427 428 if (type == UHID_CREATE) {429 /*430 * This is our messed up request with compat pointer.431 * It is largish (more than 256 bytes) so we better432 * allocate it from the heap.433 */434 struct uhid_create_req_compat *compat;435 436 compat = kzalloc(sizeof(*compat), GFP_KERNEL);437 if (!compat)438 return -ENOMEM;439 440 buffer += sizeof(type);441 len -= sizeof(type);442 if (copy_from_user(compat, buffer,443 min(len, sizeof(*compat)))) {444 kfree(compat);445 return -EFAULT;446 }447 448 /* Shuffle the data over to proper structure */449 event->type = type;450 451 memcpy(event->u.create.name, compat->name,452 sizeof(compat->name));453 memcpy(event->u.create.phys, compat->phys,454 sizeof(compat->phys));455 memcpy(event->u.create.uniq, compat->uniq,456 sizeof(compat->uniq));457 458 event->u.create.rd_data = compat_ptr(compat->rd_data);459 event->u.create.rd_size = compat->rd_size;460 461 event->u.create.bus = compat->bus;462 event->u.create.vendor = compat->vendor;463 event->u.create.product = compat->product;464 event->u.create.version = compat->version;465 event->u.create.country = compat->country;466 467 kfree(compat);468 return 0;469 }470 /* All others can be copied directly */471 }472 473 if (copy_from_user(event, buffer, min(len, sizeof(*event))))474 return -EFAULT;475 476 return 0;477}478#else479static int uhid_event_from_user(const char __user *buffer, size_t len,480 struct uhid_event *event)481{482 if (copy_from_user(event, buffer, min(len, sizeof(*event))))483 return -EFAULT;484 485 return 0;486}487#endif488 489static int uhid_dev_create2(struct uhid_device *uhid,490 const struct uhid_event *ev)491{492 struct hid_device *hid;493 size_t rd_size;494 void *rd_data;495 int ret;496 497 if (uhid->hid)498 return -EALREADY;499 500 rd_size = ev->u.create2.rd_size;501 if (rd_size <= 0 || rd_size > HID_MAX_DESCRIPTOR_SIZE)502 return -EINVAL;503 504 rd_data = kmemdup(ev->u.create2.rd_data, rd_size, GFP_KERNEL);505 if (!rd_data)506 return -ENOMEM;507 508 uhid->rd_size = rd_size;509 uhid->rd_data = rd_data;510 511 hid = hid_allocate_device();512 if (IS_ERR(hid)) {513 ret = PTR_ERR(hid);514 goto err_free;515 }516 517 BUILD_BUG_ON(sizeof(hid->name) != sizeof(ev->u.create2.name));518 strscpy(hid->name, ev->u.create2.name, sizeof(hid->name));519 BUILD_BUG_ON(sizeof(hid->phys) != sizeof(ev->u.create2.phys));520 strscpy(hid->phys, ev->u.create2.phys, sizeof(hid->phys));521 BUILD_BUG_ON(sizeof(hid->uniq) != sizeof(ev->u.create2.uniq));522 strscpy(hid->uniq, ev->u.create2.uniq, sizeof(hid->uniq));523 524 hid->ll_driver = &uhid_hid_driver;525 hid->bus = ev->u.create2.bus;526 hid->vendor = ev->u.create2.vendor;527 hid->product = ev->u.create2.product;528 hid->version = ev->u.create2.version;529 hid->country = ev->u.create2.country;530 hid->driver_data = uhid;531 hid->dev.parent = uhid_misc.this_device;532 533 uhid->hid = hid;534 uhid->running = true;535 536 /* Adding of a HID device is done through a worker, to allow HID drivers537 * which use feature requests during .probe to work, without they would538 * be blocked on devlock, which is held by uhid_char_write.539 */540 schedule_work(&uhid->worker);541 542 return 0;543 544err_free:545 kfree(uhid->rd_data);546 uhid->rd_data = NULL;547 uhid->rd_size = 0;548 return ret;549}550 551static int uhid_dev_create(struct uhid_device *uhid,552 struct uhid_event *ev)553{554 struct uhid_create_req orig;555 556 orig = ev->u.create;557 558 if (orig.rd_size <= 0 || orig.rd_size > HID_MAX_DESCRIPTOR_SIZE)559 return -EINVAL;560 if (copy_from_user(&ev->u.create2.rd_data, orig.rd_data, orig.rd_size))561 return -EFAULT;562 563 memcpy(ev->u.create2.name, orig.name, sizeof(orig.name));564 memcpy(ev->u.create2.phys, orig.phys, sizeof(orig.phys));565 memcpy(ev->u.create2.uniq, orig.uniq, sizeof(orig.uniq));566 ev->u.create2.rd_size = orig.rd_size;567 ev->u.create2.bus = orig.bus;568 ev->u.create2.vendor = orig.vendor;569 ev->u.create2.product = orig.product;570 ev->u.create2.version = orig.version;571 ev->u.create2.country = orig.country;572 573 return uhid_dev_create2(uhid, ev);574}575 576static int uhid_dev_destroy(struct uhid_device *uhid)577{578 if (!uhid->hid)579 return -EINVAL;580 581 WRITE_ONCE(uhid->running, false);582 wake_up_interruptible(&uhid->report_wait);583 584 cancel_work_sync(&uhid->worker);585 586 hid_destroy_device(uhid->hid);587 uhid->hid = NULL;588 kfree(uhid->rd_data);589 590 return 0;591}592 593static int uhid_dev_input(struct uhid_device *uhid, struct uhid_event *ev)594{595 if (!READ_ONCE(uhid->running))596 return -EINVAL;597 598 hid_input_report(uhid->hid, HID_INPUT_REPORT, ev->u.input.data,599 min_t(size_t, ev->u.input.size, UHID_DATA_MAX), 0);600 601 return 0;602}603 604static int uhid_dev_input2(struct uhid_device *uhid, struct uhid_event *ev)605{606 if (!READ_ONCE(uhid->running))607 return -EINVAL;608 609 hid_input_report(uhid->hid, HID_INPUT_REPORT, ev->u.input2.data,610 min_t(size_t, ev->u.input2.size, UHID_DATA_MAX), 0);611 612 return 0;613}614 615static int uhid_dev_get_report_reply(struct uhid_device *uhid,616 struct uhid_event *ev)617{618 if (!READ_ONCE(uhid->running))619 return -EINVAL;620 621 uhid_report_wake_up(uhid, ev->u.get_report_reply.id, ev);622 return 0;623}624 625static int uhid_dev_set_report_reply(struct uhid_device *uhid,626 struct uhid_event *ev)627{628 if (!READ_ONCE(uhid->running))629 return -EINVAL;630 631 uhid_report_wake_up(uhid, ev->u.set_report_reply.id, ev);632 return 0;633}634 635static int uhid_char_open(struct inode *inode, struct file *file)636{637 struct uhid_device *uhid;638 639 uhid = kzalloc(sizeof(*uhid), GFP_KERNEL);640 if (!uhid)641 return -ENOMEM;642 643 mutex_init(&uhid->devlock);644 mutex_init(&uhid->report_lock);645 spin_lock_init(&uhid->qlock);646 init_waitqueue_head(&uhid->waitq);647 init_waitqueue_head(&uhid->report_wait);648 uhid->running = false;649 INIT_WORK(&uhid->worker, uhid_device_add_worker);650 651 file->private_data = uhid;652 stream_open(inode, file);653 654 return 0;655}656 657static int uhid_char_release(struct inode *inode, struct file *file)658{659 struct uhid_device *uhid = file->private_data;660 unsigned int i;661 662 uhid_dev_destroy(uhid);663 664 for (i = 0; i < UHID_BUFSIZE; ++i)665 kfree(uhid->outq[i]);666 667 kfree(uhid);668 669 return 0;670}671 672static ssize_t uhid_char_read(struct file *file, char __user *buffer,673 size_t count, loff_t *ppos)674{675 struct uhid_device *uhid = file->private_data;676 int ret;677 unsigned long flags;678 size_t len;679 680 /* they need at least the "type" member of uhid_event */681 if (count < sizeof(__u32))682 return -EINVAL;683 684try_again:685 if (file->f_flags & O_NONBLOCK) {686 if (uhid->head == uhid->tail)687 return -EAGAIN;688 } else {689 ret = wait_event_interruptible(uhid->waitq,690 uhid->head != uhid->tail);691 if (ret)692 return ret;693 }694 695 ret = mutex_lock_interruptible(&uhid->devlock);696 if (ret)697 return ret;698 699 if (uhid->head == uhid->tail) {700 mutex_unlock(&uhid->devlock);701 goto try_again;702 } else {703 len = min(count, sizeof(**uhid->outq));704 if (copy_to_user(buffer, uhid->outq[uhid->tail], len)) {705 ret = -EFAULT;706 } else {707 kfree(uhid->outq[uhid->tail]);708 uhid->outq[uhid->tail] = NULL;709 710 spin_lock_irqsave(&uhid->qlock, flags);711 uhid->tail = (uhid->tail + 1) % UHID_BUFSIZE;712 spin_unlock_irqrestore(&uhid->qlock, flags);713 }714 }715 716 mutex_unlock(&uhid->devlock);717 return ret ? ret : len;718}719 720static ssize_t uhid_char_write(struct file *file, const char __user *buffer,721 size_t count, loff_t *ppos)722{723 struct uhid_device *uhid = file->private_data;724 int ret;725 size_t len;726 727 /* we need at least the "type" member of uhid_event */728 if (count < sizeof(__u32))729 return -EINVAL;730 731 ret = mutex_lock_interruptible(&uhid->devlock);732 if (ret)733 return ret;734 735 memset(&uhid->input_buf, 0, sizeof(uhid->input_buf));736 len = min(count, sizeof(uhid->input_buf));737 738 ret = uhid_event_from_user(buffer, len, &uhid->input_buf);739 if (ret)740 goto unlock;741 742 switch (uhid->input_buf.type) {743 case UHID_CREATE:744 /*745 * 'struct uhid_create_req' contains a __user pointer which is746 * copied from, so it's unsafe to allow this with elevated747 * privileges (e.g. from a setuid binary) or via kernel_write().748 */749 if (file->f_cred != current_cred()) {750 pr_err_once("UHID_CREATE from different security context by process %d (%s), this is not allowed.\n",751 task_tgid_vnr(current), current->comm);752 ret = -EACCES;753 goto unlock;754 }755 ret = uhid_dev_create(uhid, &uhid->input_buf);756 break;757 case UHID_CREATE2:758 ret = uhid_dev_create2(uhid, &uhid->input_buf);759 break;760 case UHID_DESTROY:761 ret = uhid_dev_destroy(uhid);762 break;763 case UHID_INPUT:764 ret = uhid_dev_input(uhid, &uhid->input_buf);765 break;766 case UHID_INPUT2:767 ret = uhid_dev_input2(uhid, &uhid->input_buf);768 break;769 case UHID_GET_REPORT_REPLY:770 ret = uhid_dev_get_report_reply(uhid, &uhid->input_buf);771 break;772 case UHID_SET_REPORT_REPLY:773 ret = uhid_dev_set_report_reply(uhid, &uhid->input_buf);774 break;775 default:776 ret = -EOPNOTSUPP;777 }778 779unlock:780 mutex_unlock(&uhid->devlock);781 782 /* return "count" not "len" to not confuse the caller */783 return ret ? ret : count;784}785 786static __poll_t uhid_char_poll(struct file *file, poll_table *wait)787{788 struct uhid_device *uhid = file->private_data;789 __poll_t mask = EPOLLOUT | EPOLLWRNORM; /* uhid is always writable */790 791 poll_wait(file, &uhid->waitq, wait);792 793 if (uhid->head != uhid->tail)794 mask |= EPOLLIN | EPOLLRDNORM;795 796 return mask;797}798 799static const struct file_operations uhid_fops = {800 .owner = THIS_MODULE,801 .open = uhid_char_open,802 .release = uhid_char_release,803 .read = uhid_char_read,804 .write = uhid_char_write,805 .poll = uhid_char_poll,806};807 808static struct miscdevice uhid_misc = {809 .fops = &uhid_fops,810 .minor = UHID_MINOR,811 .name = UHID_NAME,812};813module_misc_device(uhid_misc);814 815MODULE_LICENSE("GPL");816MODULE_AUTHOR("David Herrmann <dh.herrmann@gmail.com>");817MODULE_DESCRIPTION("User-space I/O driver support for HID subsystem");818MODULE_ALIAS_MISCDEV(UHID_MINOR);819MODULE_ALIAS("devname:" UHID_NAME);820