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