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