drivers/usb/gadget/function/f_hid.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * f_hid.c -- USB HID function driver
   4  *
   5  * Copyright (C) 2010 Fabien Chouteau <fabien.chouteau@barco.com>
   6  */
   7
   8 #include <linux/kernel.h>
   9 #include <linux/module.h>
  10 #include <linux/hid.h>
  11 #include <linux/idr.h>
  12 #include <linux/cdev.h>
  13 #include <linux/mutex.h>
  14 #include <linux/poll.h>
  15 #include <linux/uaccess.h>
  16 #include <linux/wait.h>
  17 #include <linux/sched.h>
  18 #include <linux/usb/g_hid.h>
  19
  20 #include "u_f.h"
  21 #include "u_hid.h"
  22
  23 #define HIDG_MINORS     4
  24
  25 static int major, minors;
  26 static struct class *hidg_class;
  27 static DEFINE_IDA(hidg_ida);
  28 static DEFINE_MUTEX(hidg_ida_lock); /* protects access to hidg_ida */
  29
  30 /*-------------------------------------------------------------------------*/
  31 /*                            HID gadget struct                            */
  32
  33 struct f_hidg_req_list {
  34         struct usb_request      *req;
  35         unsigned int            pos;
  36         struct list_head        list;
  37 };
  38
  39 struct f_hidg {
  40         /* configuration */
  41         unsigned char                   bInterfaceSubClass;
  42         unsigned char                   bInterfaceProtocol;
  43         unsigned char                   protocol;
  44         unsigned char                   idle;
  45         unsigned short                  report_desc_length;
  46         char                            *report_desc;
  47         unsigned short                  report_length;
  48         /*
  49          * use_out_ep - if true, the OUT Endpoint (interrupt out method)
  50          *              will be used to receive reports from the host
  51          *              using functions with the "intout" suffix.
  52          *              Otherwise, the OUT Endpoint will not be configured
  53          *              and the SETUP/SET_REPORT method ("ssreport" suffix)
  54          *              will be used to receive reports.
  55          */
  56         bool                            use_out_ep;
  57
  58         /* recv report */
  59         spinlock_t                      read_spinlock;
  60         wait_queue_head_t               read_queue;
  61         /* recv report - interrupt out only (use_out_ep == 1) */
  62         struct list_head                completed_out_req;
  63         unsigned int                    qlen;
  64         /* recv report - setup set_report only (use_out_ep == 0) */
  65         char                            *set_report_buf;
  66         unsigned int                    set_report_length;
  67
  68         /* send report */
  69         spinlock_t                      write_spinlock;
  70         bool                            write_pending;
  71         wait_queue_head_t               write_queue;
  72         struct usb_request              *req;
  73
  74         struct device                   dev;
  75         struct cdev                     cdev;
  76         struct usb_function             func;
  77
  78         struct usb_ep                   *in_ep;
  79         struct usb_ep                   *out_ep;
  80 };
  81
  82 static inline struct f_hidg *func_to_hidg(struct usb_function *f)
  83 {
  84         return container_of(f, struct f_hidg, func);
  85 }
  86
  87 static void hidg_release(struct device *dev)
  88 {
  89         struct f_hidg *hidg = container_of(dev, struct f_hidg, dev);
  90
  91         kfree(hidg->report_desc);
  92         kfree(hidg->set_report_buf);
  93         kfree(hidg);
  94 }
  95
  96 /*-------------------------------------------------------------------------*/
  97 /*                           Static descriptors                            */
  98
  99 static struct usb_interface_descriptor hidg_interface_desc = {
 100         .bLength                = sizeof hidg_interface_desc,
 101         .bDescriptorType        = USB_DT_INTERFACE,
 102         /* .bInterfaceNumber    = DYNAMIC */
 103         .bAlternateSetting      = 0,
 104         /* .bNumEndpoints       = DYNAMIC (depends on use_out_ep) */
 105         .bInterfaceClass        = USB_CLASS_HID,
 106         /* .bInterfaceSubClass  = DYNAMIC */
 107         /* .bInterfaceProtocol  = DYNAMIC */
 108         /* .iInterface          = DYNAMIC */
 109 };
 110
 111 static struct hid_descriptor hidg_desc = {
 112         .bLength                        = sizeof hidg_desc,
 113         .bDescriptorType                = HID_DT_HID,
 114         .bcdHID                         = cpu_to_le16(0x0101),
 115         .bCountryCode                   = 0x00,
 116         .bNumDescriptors                = 0x1,
 117         /*.desc[0].bDescriptorType      = DYNAMIC */
 118         /*.desc[0].wDescriptorLenght    = DYNAMIC */
 119 };
 120
 121 /* Super-Speed Support */
 122
 123 static struct usb_endpoint_descriptor hidg_ss_in_ep_desc = {
 124         .bLength                = USB_DT_ENDPOINT_SIZE,
 125         .bDescriptorType        = USB_DT_ENDPOINT,
 126         .bEndpointAddress       = USB_DIR_IN,
 127         .bmAttributes           = USB_ENDPOINT_XFER_INT,
 128         /*.wMaxPacketSize       = DYNAMIC */
 129         .bInterval              = 4, /* FIXME: Add this field in the
 130                                       * HID gadget configuration?
 131                                       * (struct hidg_func_descriptor)
 132                                       */
 133 };
 134
 135 static struct usb_ss_ep_comp_descriptor hidg_ss_in_comp_desc = {
 136         .bLength                = sizeof(hidg_ss_in_comp_desc),
 137         .bDescriptorType        = USB_DT_SS_ENDPOINT_COMP,
 138
 139         /* .bMaxBurst           = 0, */
 140         /* .bmAttributes        = 0, */
 141         /* .wBytesPerInterval   = DYNAMIC */
 142 };
 143
 144 static struct usb_endpoint_descriptor hidg_ss_out_ep_desc = {
 145         .bLength                = USB_DT_ENDPOINT_SIZE,
 146         .bDescriptorType        = USB_DT_ENDPOINT,
 147         .bEndpointAddress       = USB_DIR_OUT,
 148         .bmAttributes           = USB_ENDPOINT_XFER_INT,
 149         /*.wMaxPacketSize       = DYNAMIC */
 150         .bInterval              = 4, /* FIXME: Add this field in the
 151                                       * HID gadget configuration?
 152                                       * (struct hidg_func_descriptor)
 153                                       */
 154 };
 155
 156 static struct usb_ss_ep_comp_descriptor hidg_ss_out_comp_desc = {
 157         .bLength                = sizeof(hidg_ss_out_comp_desc),
 158         .bDescriptorType        = USB_DT_SS_ENDPOINT_COMP,
 159
 160         /* .bMaxBurst           = 0, */
 161         /* .bmAttributes        = 0, */
 162         /* .wBytesPerInterval   = DYNAMIC */
 163 };
 164
 165 static struct usb_descriptor_header *hidg_ss_descriptors_intout[] = {
 166         (struct usb_descriptor_header *)&hidg_interface_desc,
 167         (struct usb_descriptor_header *)&hidg_desc,
 168         (struct usb_descriptor_header *)&hidg_ss_in_ep_desc,
 169         (struct usb_descriptor_header *)&hidg_ss_in_comp_desc,
 170         (struct usb_descriptor_header *)&hidg_ss_out_ep_desc,
 171         (struct usb_descriptor_header *)&hidg_ss_out_comp_desc,
 172         NULL,
 173 };
 174
 175 static struct usb_descriptor_header *hidg_ss_descriptors_ssreport[] = {
 176         (struct usb_descriptor_header *)&hidg_interface_desc,
 177         (struct usb_descriptor_header *)&hidg_desc,
 178         (struct usb_descriptor_header *)&hidg_ss_in_ep_desc,
 179         (struct usb_descriptor_header *)&hidg_ss_in_comp_desc,
 180         NULL,
 181 };
 182
 183 /* High-Speed Support */
 184
 185 static struct usb_endpoint_descriptor hidg_hs_in_ep_desc = {
 186         .bLength                = USB_DT_ENDPOINT_SIZE,
 187         .bDescriptorType        = USB_DT_ENDPOINT,
 188         .bEndpointAddress       = USB_DIR_IN,
 189         .bmAttributes           = USB_ENDPOINT_XFER_INT,
 190         /*.wMaxPacketSize       = DYNAMIC */
 191         .bInterval              = 4, /* FIXME: Add this field in the
 192                                       * HID gadget configuration?
 193                                       * (struct hidg_func_descriptor)
 194                                       */
 195 };
 196
 197 static struct usb_endpoint_descriptor hidg_hs_out_ep_desc = {
 198         .bLength                = USB_DT_ENDPOINT_SIZE,
 199         .bDescriptorType        = USB_DT_ENDPOINT,
 200         .bEndpointAddress       = USB_DIR_OUT,
 201         .bmAttributes           = USB_ENDPOINT_XFER_INT,
 202         /*.wMaxPacketSize       = DYNAMIC */
 203         .bInterval              = 4, /* FIXME: Add this field in the
 204                                       * HID gadget configuration?
 205                                       * (struct hidg_func_descriptor)
 206                                       */
 207 };
 208
 209 static struct usb_descriptor_header *hidg_hs_descriptors_intout[] = {
 210         (struct usb_descriptor_header *)&hidg_interface_desc,
 211         (struct usb_descriptor_header *)&hidg_desc,
 212         (struct usb_descriptor_header *)&hidg_hs_in_ep_desc,
 213         (struct usb_descriptor_header *)&hidg_hs_out_ep_desc,
 214         NULL,
 215 };
 216
 217 static struct usb_descriptor_header *hidg_hs_descriptors_ssreport[] = {
 218         (struct usb_descriptor_header *)&hidg_interface_desc,
 219         (struct usb_descriptor_header *)&hidg_desc,
 220         (struct usb_descriptor_header *)&hidg_hs_in_ep_desc,
 221         NULL,
 222 };
 223
 224 /* Full-Speed Support */
 225
 226 static struct usb_endpoint_descriptor hidg_fs_in_ep_desc = {
 227         .bLength                = USB_DT_ENDPOINT_SIZE,
 228         .bDescriptorType        = USB_DT_ENDPOINT,
 229         .bEndpointAddress       = USB_DIR_IN,
 230         .bmAttributes           = USB_ENDPOINT_XFER_INT,
 231         /*.wMaxPacketSize       = DYNAMIC */
 232         .bInterval              = 10, /* FIXME: Add this field in the
 233                                        * HID gadget configuration?
 234                                        * (struct hidg_func_descriptor)
 235                                        */
 236 };
 237
 238 static struct usb_endpoint_descriptor hidg_fs_out_ep_desc = {
 239         .bLength                = USB_DT_ENDPOINT_SIZE,
 240         .bDescriptorType        = USB_DT_ENDPOINT,
 241         .bEndpointAddress       = USB_DIR_OUT,
 242         .bmAttributes           = USB_ENDPOINT_XFER_INT,
 243         /*.wMaxPacketSize       = DYNAMIC */
 244         .bInterval              = 10, /* FIXME: Add this field in the
 245                                        * HID gadget configuration?
 246                                        * (struct hidg_func_descriptor)
 247                                        */
 248 };
 249
 250 static struct usb_descriptor_header *hidg_fs_descriptors_intout[] = {
 251         (struct usb_descriptor_header *)&hidg_interface_desc,
 252         (struct usb_descriptor_header *)&hidg_desc,
 253         (struct usb_descriptor_header *)&hidg_fs_in_ep_desc,
 254         (struct usb_descriptor_header *)&hidg_fs_out_ep_desc,
 255         NULL,
 256 };
 257
 258 static struct usb_descriptor_header *hidg_fs_descriptors_ssreport[] = {
 259         (struct usb_descriptor_header *)&hidg_interface_desc,
 260         (struct usb_descriptor_header *)&hidg_desc,
 261         (struct usb_descriptor_header *)&hidg_fs_in_ep_desc,
 262         NULL,
 263 };
 264
 265 /*-------------------------------------------------------------------------*/
 266 /*                                 Strings                                 */
 267
 268 #define CT_FUNC_HID_IDX 0
 269
 270 static struct usb_string ct_func_string_defs[] = {
 271         [CT_FUNC_HID_IDX].s     = "HID Interface",
 272         {},                     /* end of list */
 273 };
 274
 275 static struct usb_gadget_strings ct_func_string_table = {
 276         .language       = 0x0409,       /* en-US */
 277         .strings        = ct_func_string_defs,
 278 };
 279
 280 static struct usb_gadget_strings *ct_func_strings[] = {
 281         &ct_func_string_table,
 282         NULL,
 283 };
 284
 285 /*-------------------------------------------------------------------------*/
 286 /*                              Char Device                                */
 287
 288 static ssize_t f_hidg_intout_read(struct file *file, char __user *buffer,
 289                                   size_t count, loff_t *ptr)
 290 {
 291         struct f_hidg *hidg = file->private_data;
 292         struct f_hidg_req_list *list;
 293         struct usb_request *req;
 294         unsigned long flags;
 295         int ret;
 296
 297         if (!count)
 298                 return 0;
 299
 300         if (!access_ok(VERIFY_WRITE, buffer, count))
 301                 return -EFAULT;
 302
 303         spin_lock_irqsave(&hidg->read_spinlock, flags);
 304
 305 #define READ_COND_INTOUT (!list_empty(&hidg->completed_out_req))
 306
 307         /* wait for at least one buffer to complete */
 308         while (!READ_COND_INTOUT) {
 309                 spin_unlock_irqrestore(&hidg->read_spinlock, flags);
 310                 if (file->f_flags & O_NONBLOCK)
 311                         return -EAGAIN;
 312
 313                 if (wait_event_interruptible(hidg->read_queue, READ_COND_INTOUT))
 314                         return -ERESTARTSYS;
 315
 316                 spin_lock_irqsave(&hidg->read_spinlock, flags);
 317         }
 318
 319         /* pick the first one */
 320         list = list_first_entry(&hidg->completed_out_req,
 321                                 struct f_hidg_req_list, list);
 322
 323         /*
 324          * Remove this from list to protect it from beign free()
 325          * while host disables our function
 326          */
 327         list_del(&list->list);
 328
 329         req = list->req;
 330         count = min_t(unsigned int, count, req->actual - list->pos);
 331         spin_unlock_irqrestore(&hidg->read_spinlock, flags);
 332
 333         /* copy to user outside spinlock */
 334         count -= copy_to_user(buffer, req->buf + list->pos, count);
 335         list->pos += count;
 336
 337         /*
 338          * if this request is completely handled and transfered to
 339          * userspace, remove its entry from the list and requeue it
 340          * again. Otherwise, we will revisit it again upon the next
 341          * call, taking into account its current read position.
 342          */
 343         if (list->pos == req->actual) {
 344                 kfree(list);
 345
 346                 req->length = hidg->report_length;
 347                 ret = usb_ep_queue(hidg->out_ep, req, GFP_KERNEL);
 348                 if (ret < 0) {
 349                         free_ep_req(hidg->out_ep, req);
 350                         return ret;
 351                 }
 352         } else {
 353                 spin_lock_irqsave(&hidg->read_spinlock, flags);
 354                 list_add(&list->list, &hidg->completed_out_req);
 355                 spin_unlock_irqrestore(&hidg->read_spinlock, flags);
 356
 357                 wake_up(&hidg->read_queue);
 358         }
 359
 360         return count;
 361 }
 362
 363 #define READ_COND_SSREPORT (hidg->set_report_buf != NULL)
 364
 365 static ssize_t f_hidg_ssreport_read(struct file *file, char __user *buffer,
 366                                     size_t count, loff_t *ptr)
 367 {
 368         struct f_hidg *hidg = file->private_data;
 369         char *tmp_buf = NULL;
 370         unsigned long flags;
 371
 372         if (!count)
 373                 return 0;
 374
 375         spin_lock_irqsave(&hidg->read_spinlock, flags);
 376
 377         while (!READ_COND_SSREPORT) {
 378                 spin_unlock_irqrestore(&hidg->read_spinlock, flags);
 379                 if (file->f_flags & O_NONBLOCK)
 380                         return -EAGAIN;
 381
 382                 if (wait_event_interruptible(hidg->read_queue, READ_COND_SSREPORT))
 383                         return -ERESTARTSYS;
 384
 385                 spin_lock_irqsave(&hidg->read_spinlock, flags);
 386         }
 387
 388         count = min_t(unsigned int, count, hidg->set_report_length);
 389         tmp_buf = hidg->set_report_buf;
 390         hidg->set_report_buf = NULL;
 391
 392         spin_unlock_irqrestore(&hidg->read_spinlock, flags);
 393
 394         if (tmp_buf != NULL) {
 395                 count -= copy_to_user(buffer, tmp_buf, count);
 396                 kfree(tmp_buf);
 397         } else {
 398                 count = -ENOMEM;
 399         }
 400
 401         wake_up(&hidg->read_queue);
 402
 403         return count;
 404 }
 405
 406 static ssize_t f_hidg_read(struct file *file, char __user *buffer,
 407                            size_t count, loff_t *ptr)
 408 {
 409         struct f_hidg *hidg = file->private_data;
 410
 411         if (hidg->use_out_ep)
 412                 return f_hidg_intout_read(file, buffer, count, ptr);
 413         else
 414                 return f_hidg_ssreport_read(file, buffer, count, ptr);
 415 }
 416
 417 static void f_hidg_req_complete(struct usb_ep *ep, struct usb_request *req)
 418 {
 419         struct f_hidg *hidg = (struct f_hidg *)ep->driver_data;
 420         unsigned long flags;
 421
 422         if (req->status != 0) {
 423                 ERROR(hidg->func.config->cdev,
 424                         "End Point Request ERROR: %d\n", req->status);
 425         }
 426
 427         spin_lock_irqsave(&hidg->write_spinlock, flags);
 428         hidg->write_pending = 0;
 429         spin_unlock_irqrestore(&hidg->write_spinlock, flags);
 430         wake_up(&hidg->write_queue);
 431 }
 432
 433 static ssize_t f_hidg_write(struct file *file, const char __user *buffer,
 434                             size_t count, loff_t *offp)
 435 {
 436         struct f_hidg *hidg  = file->private_data;
 437         struct usb_request *req;
 438         unsigned long flags;
 439         ssize_t status = -ENOMEM;
 440
 441         if (!access_ok(VERIFY_READ, buffer, count))
 442                 return -EFAULT;
 443
 444         spin_lock_irqsave(&hidg->write_spinlock, flags);
 445
 446         if (!hidg->req) {
 447                 spin_unlock_irqrestore(&hidg->write_spinlock, flags);
 448                 return -ESHUTDOWN;
 449         }
 450
 451 #define WRITE_COND (!hidg->write_pending)
 452 try_again:
 453         /* write queue */
 454         while (!WRITE_COND) {
 455                 spin_unlock_irqrestore(&hidg->write_spinlock, flags);
 456                 if (file->f_flags & O_NONBLOCK)
 457                         return -EAGAIN;
 458
 459                 if (wait_event_interruptible_exclusive(
 460                                 hidg->write_queue, WRITE_COND))
 461                         return -ERESTARTSYS;
 462
 463                 spin_lock_irqsave(&hidg->write_spinlock, flags);
 464         }
 465
 466         hidg->write_pending = 1;
 467         req = hidg->req;
 468         count  = min_t(unsigned, count, hidg->report_length);
 469
 470         spin_unlock_irqrestore(&hidg->write_spinlock, flags);
 471
 472         if (!req) {
 473                 ERROR(hidg->func.config->cdev, "hidg->req is NULL\n");
 474                 status = -ESHUTDOWN;
 475                 goto release_write_pending;
 476         }
 477
 478         status = copy_from_user(req->buf, buffer, count);
 479         if (status != 0) {
 480                 ERROR(hidg->func.config->cdev,
 481                         "copy_from_user error\n");
 482                 status = -EINVAL;
 483                 goto release_write_pending;
 484         }
 485
 486         spin_lock_irqsave(&hidg->write_spinlock, flags);
 487
 488         /* when our function has been disabled by host */
 489         if (!hidg->req) {
 490                 free_ep_req(hidg->in_ep, req);
 491                 /*
 492                  * TODO
 493                  * Should we fail with error here?
 494                  */
 495                 goto try_again;
 496         }
 497
 498         req->status   = 0;
 499         req->zero     = 0;
 500         req->length   = count;
 501         req->complete = f_hidg_req_complete;
 502         req->context  = hidg;
 503
 504         spin_unlock_irqrestore(&hidg->write_spinlock, flags);
 505
 506         if (!hidg->in_ep->enabled) {
 507                 ERROR(hidg->func.config->cdev, "in_ep is disabled\n");
 508                 status = -ESHUTDOWN;
 509                 goto release_write_pending;
 510         }
 511
 512         status = usb_ep_queue(hidg->in_ep, req, GFP_ATOMIC);
 513         if (status < 0)
 514                 goto release_write_pending;
 515         else
 516                 status = count;
 517
 518         return status;
 519 release_write_pending:
 520         spin_lock_irqsave(&hidg->write_spinlock, flags);
 521         hidg->write_pending = 0;
 522         spin_unlock_irqrestore(&hidg->write_spinlock, flags);
 523
 524         wake_up(&hidg->write_queue);
 525
 526         return status;
 527 }
 528
 529 static __poll_t f_hidg_poll(struct file *file, poll_table *wait)
 530 {
 531         struct f_hidg   *hidg  = file->private_data;
 532         __poll_t        ret = 0;
 533
 534         poll_wait(file, &hidg->read_queue, wait);
 535         poll_wait(file, &hidg->write_queue, wait);
 536
 537         if (WRITE_COND)
 538                 ret |= EPOLLOUT | EPOLLWRNORM;
 539
 540         if (hidg->use_out_ep) {
 541                 if (READ_COND_INTOUT)
 542                         ret |= EPOLLIN | EPOLLRDNORM;
 543         } else {
 544                 if (READ_COND_SSREPORT)
 545                         ret |= EPOLLIN | EPOLLRDNORM;
 546         }
 547
 548         return ret;
 549 }
 550
 551 #undef WRITE_COND
 552 #undef READ_COND_SSREPORT
 553 #undef READ_COND_INTOUT
 554
 555 static int f_hidg_release(struct inode *inode, struct file *fd)
 556 {
 557         fd->private_data = NULL;
 558         return 0;
 559 }
 560
 561 static int f_hidg_open(struct inode *inode, struct file *fd)
 562 {
 563         struct f_hidg *hidg =
 564                 container_of(inode->i_cdev, struct f_hidg, cdev);
 565
 566         fd->private_data = hidg;
 567
 568         return 0;
 569 }
 570
 571 /*-------------------------------------------------------------------------*/
 572 /*                                usb_function                             */
 573
 574 static inline struct usb_request *hidg_alloc_ep_req(struct usb_ep *ep,
 575                                                     unsigned length)
 576 {
 577         return alloc_ep_req(ep, length);
 578 }
 579
 580 static void hidg_intout_complete(struct usb_ep *ep, struct usb_request *req)
 581 {
 582         struct f_hidg *hidg = (struct f_hidg *) req->context;
 583         struct usb_composite_dev *cdev = hidg->func.config->cdev;
 584         struct f_hidg_req_list *req_list;
 585         unsigned long flags;
 586
 587         switch (req->status) {
 588         case 0:
 589                 req_list = kzalloc(sizeof(*req_list), GFP_ATOMIC);
 590                 if (!req_list) {
 591                         ERROR(cdev, "Unable to allocate mem for req_list\n");
 592                         goto free_req;
 593                 }
 594
 595                 req_list->req = req;
 596
 597                 spin_lock_irqsave(&hidg->read_spinlock, flags);
 598                 list_add_tail(&req_list->list, &hidg->completed_out_req);
 599                 spin_unlock_irqrestore(&hidg->read_spinlock, flags);
 600
 601                 wake_up(&hidg->read_queue);
 602                 break;
 603         default:
 604                 ERROR(cdev, "Set report failed %d\n", req->status);
 605                 /* FALLTHROUGH */
 606         case -ECONNABORTED:             /* hardware forced ep reset */
 607         case -ECONNRESET:               /* request dequeued */
 608         case -ESHUTDOWN:                /* disconnect from host */
 609 free_req:
 610                 free_ep_req(ep, req);
 611                 return;
 612         }
 613 }
 614
 615 static void hidg_ssreport_complete(struct usb_ep *ep, struct usb_request *req)
 616 {
 617         struct f_hidg *hidg = (struct f_hidg *)req->context;
 618         struct usb_composite_dev *cdev = hidg->func.config->cdev;
 619         char *new_buf = NULL;
 620         unsigned long flags;
 621
 622         if (req->status != 0 || req->buf == NULL || req->actual == 0) {
 623                 ERROR(cdev,
 624                       "%s FAILED: status=%d, buf=%p, actual=%d\n",
 625                       __func__, req->status, req->buf, req->actual);
 626                 return;
 627         }
 628
 629         spin_lock_irqsave(&hidg->read_spinlock, flags);
 630
 631         new_buf = krealloc(hidg->set_report_buf, req->actual, GFP_ATOMIC);
 632         if (new_buf == NULL) {
 633                 spin_unlock_irqrestore(&hidg->read_spinlock, flags);
 634                 return;
 635         }
 636         hidg->set_report_buf = new_buf;
 637
 638         hidg->set_report_length = req->actual;
 639         memcpy(hidg->set_report_buf, req->buf, req->actual);
 640
 641         spin_unlock_irqrestore(&hidg->read_spinlock, flags);
 642
 643         wake_up(&hidg->read_queue);
 644 }
 645
 646 static int hidg_setup(struct usb_function *f,
 647                 const struct usb_ctrlrequest *ctrl)
 648 {
 649         struct f_hidg                   *hidg = func_to_hidg(f);
 650         struct usb_composite_dev        *cdev = f->config->cdev;
 651         struct usb_request              *req  = cdev->req;
 652         int status = 0;
 653         __u16 value, length;
 654
 655         value   = __le16_to_cpu(ctrl->wValue);
 656         length  = __le16_to_cpu(ctrl->wLength);
 657
 658         VDBG(cdev,
 659              "%s crtl_request : bRequestType:0x%x bRequest:0x%x Value:0x%x\n",
 660              __func__, ctrl->bRequestType, ctrl->bRequest, value);
 661
 662         switch ((ctrl->bRequestType << 8) | ctrl->bRequest) {
 663         case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
 664                   | HID_REQ_GET_REPORT):
 665                 VDBG(cdev, "get_report\n");
 666
 667                 /* send an empty report */
 668                 length = min_t(unsigned, length, hidg->report_length);
 669                 memset(req->buf, 0x0, length);
 670
 671                 goto respond;
 672                 break;
 673
 674         case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
 675                   | HID_REQ_GET_PROTOCOL):
 676                 VDBG(cdev, "get_protocol\n");
 677                 length = min_t(unsigned int, length, 1);
 678                 ((u8 *) req->buf)[0] = hidg->protocol;
 679                 goto respond;
 680                 break;
 681
 682         case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
 683                   | HID_REQ_GET_IDLE):
 684                 VDBG(cdev, "get_idle\n");
 685                 length = min_t(unsigned int, length, 1);
 686                 ((u8 *) req->buf)[0] = hidg->idle;
 687                 goto respond;
 688                 break;
 689
 690         case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
 691                   | HID_REQ_SET_REPORT):
 692                 VDBG(cdev, "set_report | wLength=%d\n", ctrl->wLength);
 693                 if (hidg->use_out_ep)
 694                         goto stall;
 695                 req->complete = hidg_ssreport_complete;
 696                 req->context  = hidg;
 697                 goto respond;
 698                 break;
 699
 700         case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
 701                   | HID_REQ_SET_PROTOCOL):
 702                 VDBG(cdev, "set_protocol\n");
 703                 if (value > HID_REPORT_PROTOCOL)
 704                         goto stall;
 705                 length = 0;
 706                 /*
 707                  * We assume that programs implementing the Boot protocol
 708                  * are also compatible with the Report Protocol
 709                  */
 710                 if (hidg->bInterfaceSubClass == USB_INTERFACE_SUBCLASS_BOOT) {
 711                         hidg->protocol = value;
 712                         goto respond;
 713                 }
 714                 goto stall;
 715                 break;
 716
 717         case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
 718                   | HID_REQ_SET_IDLE):
 719                 VDBG(cdev, "set_idle\n");
 720                 length = 0;
 721                 hidg->idle = value >> 8;
 722                 goto respond;
 723                 break;
 724
 725         case ((USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_INTERFACE) << 8
 726                   | USB_REQ_GET_DESCRIPTOR):
 727                 switch (value >> 8) {
 728                 case HID_DT_HID:
 729                 {
 730                         struct hid_descriptor hidg_desc_copy = hidg_desc;
 731
 732                         VDBG(cdev, "USB_REQ_GET_DESCRIPTOR: HID\n");
 733                         hidg_desc_copy.desc[0].bDescriptorType = HID_DT_REPORT;
 734                         hidg_desc_copy.desc[0].wDescriptorLength =
 735                                 cpu_to_le16(hidg->report_desc_length);
 736
 737                         length = min_t(unsigned short, length,
 738                                                    hidg_desc_copy.bLength);
 739                         memcpy(req->buf, &hidg_desc_copy, length);
 740                         goto respond;
 741                         break;
 742                 }
 743                 case HID_DT_REPORT:
 744                         VDBG(cdev, "USB_REQ_GET_DESCRIPTOR: REPORT\n");
 745                         length = min_t(unsigned short, length,
 746                                                    hidg->report_desc_length);
 747                         memcpy(req->buf, hidg->report_desc, length);
 748                         goto respond;
 749                         break;
 750
 751                 default:
 752                         VDBG(cdev, "Unknown descriptor request 0x%x\n",
 753                                  value >> 8);
 754                         goto stall;
 755                         break;
 756                 }
 757                 break;
 758
 759         default:
 760                 VDBG(cdev, "Unknown request 0x%x\n",
 761                          ctrl->bRequest);
 762                 goto stall;
 763                 break;
 764         }
 765
 766 stall:
 767         return -EOPNOTSUPP;
 768
 769 respond:
 770         req->zero = 0;
 771         req->length = length;
 772         status = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
 773         if (status < 0)
 774                 ERROR(cdev, "usb_ep_queue error on ep0 %d\n", value);
 775         return status;
 776 }
 777
 778 static void hidg_disable(struct usb_function *f)
 779 {
 780         struct f_hidg *hidg = func_to_hidg(f);
 781         struct f_hidg_req_list *list, *next;
 782         unsigned long flags;
 783
 784         usb_ep_disable(hidg->in_ep);
 785
 786         if (hidg->out_ep) {
 787                 usb_ep_disable(hidg->out_ep);
 788
 789                 spin_lock_irqsave(&hidg->read_spinlock, flags);
 790                 list_for_each_entry_safe(list, next, &hidg->completed_out_req, list) {
 791                         free_ep_req(hidg->out_ep, list->req);
 792                         list_del(&list->list);
 793                         kfree(list);
 794                 }
 795                 spin_unlock_irqrestore(&hidg->read_spinlock, flags);
 796         }
 797
 798         spin_lock_irqsave(&hidg->write_spinlock, flags);
 799         if (!hidg->write_pending) {
 800                 free_ep_req(hidg->in_ep, hidg->req);
 801                 hidg->write_pending = 1;
 802         }
 803
 804         hidg->req = NULL;
 805         spin_unlock_irqrestore(&hidg->write_spinlock, flags);
 806 }
 807
 808 static int hidg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
 809 {
 810         struct usb_composite_dev                *cdev = f->config->cdev;
 811         struct f_hidg                           *hidg = func_to_hidg(f);
 812         struct usb_request                      *req_in = NULL;
 813         unsigned long                           flags;
 814         int i, status = 0;
 815
 816         VDBG(cdev, "hidg_set_alt intf:%d alt:%d\n", intf, alt);
 817
 818         if (hidg->in_ep != NULL) {
 819                 /* restart endpoint */
 820                 usb_ep_disable(hidg->in_ep);
 821
 822                 status = config_ep_by_speed(f->config->cdev->gadget, f,
 823                                             hidg->in_ep);
 824                 if (status) {
 825                         ERROR(cdev, "config_ep_by_speed FAILED!\n");
 826                         goto fail;
 827                 }
 828                 status = usb_ep_enable(hidg->in_ep);
 829                 if (status < 0) {
 830                         ERROR(cdev, "Enable IN endpoint FAILED!\n");
 831                         goto fail;
 832                 }
 833                 hidg->in_ep->driver_data = hidg;
 834
 835                 req_in = hidg_alloc_ep_req(hidg->in_ep, hidg->report_length);
 836                 if (!req_in) {
 837                         status = -ENOMEM;
 838                         goto disable_ep_in;
 839                 }
 840         }
 841
 842         if (hidg->use_out_ep && hidg->out_ep != NULL) {
 843                 /* restart endpoint */
 844                 usb_ep_disable(hidg->out_ep);
 845
 846                 status = config_ep_by_speed(f->config->cdev->gadget, f,
 847                                             hidg->out_ep);
 848                 if (status) {
 849                         ERROR(cdev, "config_ep_by_speed FAILED!\n");
 850                         goto free_req_in;
 851                 }
 852                 status = usb_ep_enable(hidg->out_ep);
 853                 if (status < 0) {
 854                         ERROR(cdev, "Enable OUT endpoint FAILED!\n");
 855                         goto free_req_in;
 856                 }
 857                 hidg->out_ep->driver_data = hidg;
 858
 859                 /*
 860                  * allocate a bunch of read buffers and queue them all at once.
 861                  */
 862                 for (i = 0; i < hidg->qlen && status == 0; i++) {
 863                         struct usb_request *req =
 864                                         hidg_alloc_ep_req(hidg->out_ep,
 865                                                           hidg->report_length);
 866                         if (req) {
 867                                 req->complete = hidg_intout_complete;
 868                                 req->context  = hidg;
 869                                 status = usb_ep_queue(hidg->out_ep, req,
 870                                                       GFP_ATOMIC);
 871                                 if (status) {
 872                                         ERROR(cdev, "%s queue req --> %d\n",
 873                                                 hidg->out_ep->name, status);
 874                                         free_ep_req(hidg->out_ep, req);
 875                                 }
 876                         } else {
 877                                 status = -ENOMEM;
 878                                 goto disable_out_ep;
 879                         }
 880                 }
 881         }
 882
 883         if (hidg->in_ep != NULL) {
 884                 spin_lock_irqsave(&hidg->write_spinlock, flags);
 885                 hidg->req = req_in;
 886                 hidg->write_pending = 0;
 887                 spin_unlock_irqrestore(&hidg->write_spinlock, flags);
 888
 889                 wake_up(&hidg->write_queue);
 890         }
 891         return 0;
 892 disable_out_ep:
 893         if (hidg->out_ep)
 894                 usb_ep_disable(hidg->out_ep);
 895 free_req_in:
 896         if (req_in)
 897                 free_ep_req(hidg->in_ep, req_in);
 898
 899 disable_ep_in:
 900         if (hidg->in_ep)
 901                 usb_ep_disable(hidg->in_ep);
 902
 903 fail:
 904         return status;
 905 }
 906
 907 static const struct file_operations f_hidg_fops = {
 908         .owner          = THIS_MODULE,
 909         .open           = f_hidg_open,
 910         .release        = f_hidg_release,
 911         .write          = f_hidg_write,
 912         .read           = f_hidg_read,
 913         .poll           = f_hidg_poll,
 914         .llseek         = noop_llseek,
 915 };
 916
 917 static int hidg_bind(struct usb_configuration *c, struct usb_function *f)
 918 {
 919         struct usb_ep           *ep;
 920         struct f_hidg           *hidg = func_to_hidg(f);
 921         struct usb_string       *us;
 922         int                     status;
 923
 924         /* maybe allocate device-global string IDs, and patch descriptors */
 925         us = usb_gstrings_attach(c->cdev, ct_func_strings,
 926                                  ARRAY_SIZE(ct_func_string_defs));
 927         if (IS_ERR(us))
 928                 return PTR_ERR(us);
 929         hidg_interface_desc.iInterface = us[CT_FUNC_HID_IDX].id;
 930
 931         /* allocate instance-specific interface IDs, and patch descriptors */
 932         status = usb_interface_id(c, f);
 933         if (status < 0)
 934                 goto fail;
 935         hidg_interface_desc.bInterfaceNumber = status;
 936
 937         /* allocate instance-specific endpoints */
 938         status = -ENODEV;
 939         ep = usb_ep_autoconfig(c->cdev->gadget, &hidg_fs_in_ep_desc);
 940         if (!ep)
 941                 goto fail;
 942         hidg->in_ep = ep;
 943
 944         hidg->out_ep = NULL;
 945         if (hidg->use_out_ep) {
 946                 ep = usb_ep_autoconfig(c->cdev->gadget, &hidg_fs_out_ep_desc);
 947                 if (!ep)
 948                         goto fail;
 949                 hidg->out_ep = ep;
 950         }
 951
 952         /* used only if use_out_ep == 1 */
 953         hidg->set_report_buf = NULL;
 954
 955         /* set descriptor dynamic values */
 956         hidg_interface_desc.bInterfaceSubClass = hidg->bInterfaceSubClass;
 957         hidg_interface_desc.bInterfaceProtocol = hidg->bInterfaceProtocol;
 958         hidg_interface_desc.bNumEndpoints = hidg->use_out_ep ? 2 : 1;
 959         hidg->protocol = HID_REPORT_PROTOCOL;
 960         hidg->idle = 1;
 961         hidg_ss_in_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length);
 962         hidg_ss_in_comp_desc.wBytesPerInterval =
 963                                 cpu_to_le16(hidg->report_length);
 964         hidg_hs_in_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length);
 965         hidg_fs_in_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length);
 966         hidg_ss_out_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length);
 967         hidg_ss_out_comp_desc.wBytesPerInterval =
 968                                 cpu_to_le16(hidg->report_length);
 969         hidg_hs_out_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length);
 970         hidg_fs_out_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length);
 971         /*
 972          * We can use hidg_desc struct here but we should not relay
 973          * that its content won't change after returning from this function.
 974          */
 975         hidg_desc.desc[0].bDescriptorType = HID_DT_REPORT;
 976         hidg_desc.desc[0].wDescriptorLength =
 977                 cpu_to_le16(hidg->report_desc_length);
 978
 979         hidg_hs_in_ep_desc.bEndpointAddress =
 980                 hidg_fs_in_ep_desc.bEndpointAddress;
 981         hidg_hs_out_ep_desc.bEndpointAddress =
 982                 hidg_fs_out_ep_desc.bEndpointAddress;
 983
 984         hidg_ss_in_ep_desc.bEndpointAddress =
 985                 hidg_fs_in_ep_desc.bEndpointAddress;
 986         hidg_ss_out_ep_desc.bEndpointAddress =
 987                 hidg_fs_out_ep_desc.bEndpointAddress;
 988
 989         if (hidg->use_out_ep)
 990                 status = usb_assign_descriptors(f,
 991                         hidg_fs_descriptors_intout,
 992                         hidg_hs_descriptors_intout,
 993                         hidg_ss_descriptors_intout,
 994                         hidg_ss_descriptors_intout);
 995         else
 996                 status = usb_assign_descriptors(f,
 997                         hidg_fs_descriptors_ssreport,
 998                         hidg_hs_descriptors_ssreport,
 999                         hidg_ss_descriptors_ssreport,
1000                         hidg_ss_descriptors_ssreport);
1001
1002         if (status)
1003                 goto fail;
1004
1005         spin_lock_init(&hidg->write_spinlock);
1006         hidg->write_pending = 1;
1007         hidg->req = NULL;
1008         spin_lock_init(&hidg->read_spinlock);
1009         init_waitqueue_head(&hidg->write_queue);
1010         init_waitqueue_head(&hidg->read_queue);
1011         INIT_LIST_HEAD(&hidg->completed_out_req);
1012
1013         /* create char device */
1014         cdev_init(&hidg->cdev, &f_hidg_fops);
1015         status = cdev_device_add(&hidg->cdev, &hidg->dev);
1016         if (status)
1017                 goto fail_free_descs;
1018
1019         return 0;
1020 fail_free_descs:
1021         usb_free_all_descriptors(f);
1022 fail:
1023         ERROR(f->config->cdev, "hidg_bind FAILED\n");
1024         if (hidg->req != NULL)
1025                 free_ep_req(hidg->in_ep, hidg->req);
1026
1027         return status;
1028 }
1029
1030 static inline int hidg_get_minor(void)
1031 {
1032         int ret;
1033
1034         ret = ida_simple_get(&hidg_ida, 0, 0, GFP_KERNEL);
1035         if (ret >= HIDG_MINORS) {
1036                 ida_simple_remove(&hidg_ida, ret);
1037                 ret = -ENODEV;
1038         }
1039
1040         return ret;
1041 }
1042
1043 static inline struct f_hid_opts *to_f_hid_opts(struct config_item *item)
1044 {
1045         return container_of(to_config_group(item), struct f_hid_opts,
1046                             func_inst.group);
1047 }
1048
1049 static void hid_attr_release(struct config_item *item)
1050 {
1051         struct f_hid_opts *opts = to_f_hid_opts(item);
1052
1053         usb_put_function_instance(&opts->func_inst);
1054 }
1055
1056 static struct configfs_item_operations hidg_item_ops = {
1057         .release        = hid_attr_release,
1058 };
1059
1060 #define F_HID_OPT(name, prec, limit)                                    \
1061 static ssize_t f_hid_opts_##name##_show(struct config_item *item, char *page)\
1062 {                                                                       \
1063         struct f_hid_opts *opts = to_f_hid_opts(item);                  \
1064         int result;                                                     \
1065                                                                         \
1066         mutex_lock(&opts->lock);                                        \
1067         result = sprintf(page, "%d\n", opts->name);                     \
1068         mutex_unlock(&opts->lock);                                      \
1069                                                                         \
1070         return result;                                                  \
1071 }                                                                       \
1072                                                                         \
1073 static ssize_t f_hid_opts_##name##_store(struct config_item *item,      \
1074                                          const char *page, size_t len)  \
1075 {                                                                       \
1076         struct f_hid_opts *opts = to_f_hid_opts(item);                  \
1077         int ret;                                                        \
1078         u##prec num;                                                    \
1079                                                                         \
1080         mutex_lock(&opts->lock);                                        \
1081         if (opts->refcnt) {                                             \
1082                 ret = -EBUSY;                                           \
1083                 goto end;                                               \
1084         }                                                               \
1085                                                                         \
1086         ret = kstrtou##prec(page, 0, &num);                             \
1087         if (ret)                                                        \
1088                 goto end;                                               \
1089                                                                         \
1090         if (num > limit) {                                              \
1091                 ret = -EINVAL;                                          \
1092                 goto end;                                               \
1093         }                                                               \
1094         opts->name = num;                                               \
1095         ret = len;                                                      \
1096                                                                         \
1097 end:                                                                    \
1098         mutex_unlock(&opts->lock);                                      \
1099         return ret;                                                     \
1100 }                                                                       \
1101                                                                         \
1102 CONFIGFS_ATTR(f_hid_opts_, name)
1103
1104 F_HID_OPT(subclass, 8, 255);
1105 F_HID_OPT(protocol, 8, 255);
1106 F_HID_OPT(no_out_endpoint, 8, 1);
1107 F_HID_OPT(report_length, 16, 65535);
1108
1109 static ssize_t f_hid_opts_report_desc_show(struct config_item *item, char *page)
1110 {
1111         struct f_hid_opts *opts = to_f_hid_opts(item);
1112         int result;
1113
1114         mutex_lock(&opts->lock);
1115         result = opts->report_desc_length;
1116         memcpy(page, opts->report_desc, opts->report_desc_length);
1117         mutex_unlock(&opts->lock);
1118
1119         return result;
1120 }
1121
1122 static ssize_t f_hid_opts_report_desc_store(struct config_item *item,
1123                                             const char *page, size_t len)
1124 {
1125         struct f_hid_opts *opts = to_f_hid_opts(item);
1126         int ret = -EBUSY;
1127         char *d;
1128
1129         mutex_lock(&opts->lock);
1130
1131         if (opts->refcnt)
1132                 goto end;
1133         if (len > PAGE_SIZE) {
1134                 ret = -ENOSPC;
1135                 goto end;
1136         }
1137         d = kmemdup(page, len, GFP_KERNEL);
1138         if (!d) {
1139                 ret = -ENOMEM;
1140                 goto end;
1141         }
1142         kfree(opts->report_desc);
1143         opts->report_desc = d;
1144         opts->report_desc_length = len;
1145         opts->report_desc_alloc = true;
1146         ret = len;
1147 end:
1148         mutex_unlock(&opts->lock);
1149         return ret;
1150 }
1151
1152 CONFIGFS_ATTR(f_hid_opts_, report_desc);
1153
1154 static ssize_t f_hid_opts_dev_show(struct config_item *item, char *page)
1155 {
1156         struct f_hid_opts *opts = to_f_hid_opts(item);
1157
1158         return sprintf(page, "%d:%d\n", major, opts->minor);
1159 }
1160
1161 CONFIGFS_ATTR_RO(f_hid_opts_, dev);
1162
1163 static struct configfs_attribute *hid_attrs[] = {
1164         &f_hid_opts_attr_subclass,
1165         &f_hid_opts_attr_protocol,
1166         &f_hid_opts_attr_no_out_endpoint,
1167         &f_hid_opts_attr_report_length,
1168         &f_hid_opts_attr_report_desc,
1169         &f_hid_opts_attr_dev,
1170         NULL,
1171 };
1172
1173 static const struct config_item_type hid_func_type = {
1174         .ct_item_ops    = &hidg_item_ops,
1175         .ct_attrs       = hid_attrs,
1176         .ct_owner       = THIS_MODULE,
1177 };
1178
1179 static inline void hidg_put_minor(int minor)
1180 {
1181         ida_simple_remove(&hidg_ida, minor);
1182 }
1183
1184 static void hidg_free_inst(struct usb_function_instance *f)
1185 {
1186         struct f_hid_opts *opts;
1187
1188         opts = container_of(f, struct f_hid_opts, func_inst);
1189
1190         mutex_lock(&hidg_ida_lock);
1191
1192         hidg_put_minor(opts->minor);
1193         if (ida_is_empty(&hidg_ida))
1194                 ghid_cleanup();
1195
1196         mutex_unlock(&hidg_ida_lock);
1197
1198         if (opts->report_desc_alloc)
1199                 kfree(opts->report_desc);
1200
1201         kfree(opts);
1202 }
1203
1204 static struct usb_function_instance *hidg_alloc_inst(void)
1205 {
1206         struct f_hid_opts *opts;
1207         struct usb_function_instance *ret;
1208         int status = 0;
1209
1210         opts = kzalloc(sizeof(*opts), GFP_KERNEL);
1211         if (!opts)
1212                 return ERR_PTR(-ENOMEM);
1213         mutex_init(&opts->lock);
1214         opts->func_inst.free_func_inst = hidg_free_inst;
1215         ret = &opts->func_inst;
1216
1217         mutex_lock(&hidg_ida_lock);
1218
1219         if (ida_is_empty(&hidg_ida)) {
1220                 status = ghid_setup(NULL, HIDG_MINORS);
1221                 if (status)  {
1222                         ret = ERR_PTR(status);
1223                         kfree(opts);
1224                         goto unlock;
1225                 }
1226         }
1227
1228         opts->minor = hidg_get_minor();
1229         if (opts->minor < 0) {
1230                 ret = ERR_PTR(opts->minor);
1231                 kfree(opts);
1232                 if (ida_is_empty(&hidg_ida))
1233                         ghid_cleanup();
1234                 goto unlock;
1235         }
1236         config_group_init_type_name(&opts->func_inst.group, "", &hid_func_type);
1237
1238 unlock:
1239         mutex_unlock(&hidg_ida_lock);
1240         return ret;
1241 }
1242
1243 static void hidg_free(struct usb_function *f)
1244 {
1245         struct f_hidg *hidg;
1246         struct f_hid_opts *opts;
1247
1248         hidg = func_to_hidg(f);
1249         opts = container_of(f->fi, struct f_hid_opts, func_inst);
1250         put_device(&hidg->dev);
1251         mutex_lock(&opts->lock);
1252         --opts->refcnt;
1253         mutex_unlock(&opts->lock);
1254 }
1255
1256 static void hidg_unbind(struct usb_configuration *c, struct usb_function *f)
1257 {
1258         struct f_hidg *hidg = func_to_hidg(f);
1259
1260         cdev_device_del(&hidg->cdev, &hidg->dev);
1261
1262         usb_free_all_descriptors(f);
1263 }
1264
1265 static struct usb_function *hidg_alloc(struct usb_function_instance *fi)
1266 {
1267         struct f_hidg *hidg;
1268         struct f_hid_opts *opts;
1269         int ret;
1270
1271         /* allocate and initialize one new instance */
1272         hidg = kzalloc(sizeof(*hidg), GFP_KERNEL);
1273         if (!hidg)
1274                 return ERR_PTR(-ENOMEM);
1275
1276         opts = container_of(fi, struct f_hid_opts, func_inst);
1277
1278         mutex_lock(&opts->lock);
1279         ++opts->refcnt;
1280
1281         device_initialize(&hidg->dev);
1282         hidg->dev.release = hidg_release;
1283         hidg->dev.class = hidg_class;
1284         hidg->dev.devt = MKDEV(major, opts->minor);
1285         ret = dev_set_name(&hidg->dev, "hidg%d", opts->minor);
1286         if (ret) {
1287                 --opts->refcnt;
1288                 mutex_unlock(&opts->lock);
1289                 return ERR_PTR(ret);
1290         }
1291
1292         hidg->bInterfaceSubClass = opts->subclass;
1293         hidg->bInterfaceProtocol = opts->protocol;
1294         hidg->report_length = opts->report_length;
1295         hidg->report_desc_length = opts->report_desc_length;
1296         if (opts->report_desc) {
1297                 hidg->report_desc = kmemdup(opts->report_desc,
1298                                             opts->report_desc_length,
1299                                             GFP_KERNEL);
1300                 if (!hidg->report_desc) {
1301                         put_device(&hidg->dev);
1302                         --opts->refcnt;
1303                         mutex_unlock(&opts->lock);
1304                         return ERR_PTR(-ENOMEM);
1305                 }
1306         }
1307         hidg->use_out_ep = !opts->no_out_endpoint;
1308
1309         mutex_unlock(&opts->lock);
1310
1311         hidg->func.name    = "hid";
1312         hidg->func.bind    = hidg_bind;
1313         hidg->func.unbind  = hidg_unbind;
1314         hidg->func.set_alt = hidg_set_alt;
1315         hidg->func.disable = hidg_disable;
1316         hidg->func.setup   = hidg_setup;
1317         hidg->func.free_func = hidg_free;
1318
1319         /* this could me made configurable at some point */
1320         hidg->qlen         = 4;
1321
1322         return &hidg->func;
1323 }
1324
1325 DECLARE_USB_FUNCTION_INIT(hid, hidg_alloc_inst, hidg_alloc);
1326 MODULE_LICENSE("GPL");
1327 MODULE_AUTHOR("Fabien Chouteau");
1328
1329 int ghid_setup(struct usb_gadget *g, int count)
1330 {
1331         int status;
1332         dev_t dev;
1333
1334         hidg_class = class_create(THIS_MODULE, "hidg");
1335         if (IS_ERR(hidg_class)) {
1336                 status = PTR_ERR(hidg_class);
1337                 hidg_class = NULL;
1338                 return status;
1339         }
1340
1341         status = alloc_chrdev_region(&dev, 0, count, "hidg");
1342         if (status) {
1343                 class_destroy(hidg_class);
1344                 hidg_class = NULL;
1345                 return status;
1346         }
1347
1348         major = MAJOR(dev);
1349         minors = count;
1350
1351         return 0;
1352 }
1353
1354 void ghid_cleanup(void)
1355 {
1356         if (major) {
1357                 unregister_chrdev_region(MKDEV(major, 0), minors);
1358                 major = minors = 0;
1359         }
1360
1361         class_destroy(hidg_class);
1362         hidg_class = NULL;
1363 }