1 /* 2 * f_hid.c -- USB HID function driver 3 * 4 * Copyright (C) 2010 Fabien Chouteau <fabien.chouteau@barco.com> 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License, or 9 * (at your option) any later version. 10 */ 11 12 #include <linux/kernel.h> 13 #include <linux/module.h> 14 #include <linux/hid.h> 15 #include <linux/idr.h> 16 #include <linux/cdev.h> 17 #include <linux/mutex.h> 18 #include <linux/poll.h> 19 #include <linux/uaccess.h> 20 #include <linux/wait.h> 21 #include <linux/sched.h> 22 #include <linux/usb/g_hid.h> 23 24 #include "u_f.h" 25 #include "u_hid.h" 26 27 #define HIDG_MINORS 4 28 29 static int major, minors; 30 static struct class *hidg_class; 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 short report_desc_length; 48 char *report_desc; 49 unsigned short report_length; 50 51 /* recv report */ 52 struct list_head completed_out_req; 53 spinlock_t spinlock; 54 wait_queue_head_t read_queue; 55 unsigned int qlen; 56 57 /* send report */ 58 struct mutex lock; 59 bool write_pending; 60 wait_queue_head_t write_queue; 61 struct usb_request *req; 62 63 int minor; 64 struct cdev cdev; 65 struct usb_function func; 66 67 struct usb_ep *in_ep; 68 struct usb_ep *out_ep; 69 }; 70 71 static inline struct f_hidg *func_to_hidg(struct usb_function *f) 72 { 73 return container_of(f, struct f_hidg, func); 74 } 75 76 /*-------------------------------------------------------------------------*/ 77 /* Static descriptors */ 78 79 static struct usb_interface_descriptor hidg_interface_desc = { 80 .bLength = sizeof hidg_interface_desc, 81 .bDescriptorType = USB_DT_INTERFACE, 82 /* .bInterfaceNumber = DYNAMIC */ 83 .bAlternateSetting = 0, 84 .bNumEndpoints = 2, 85 .bInterfaceClass = USB_CLASS_HID, 86 /* .bInterfaceSubClass = DYNAMIC */ 87 /* .bInterfaceProtocol = DYNAMIC */ 88 /* .iInterface = DYNAMIC */ 89 }; 90 91 static struct hid_descriptor hidg_desc = { 92 .bLength = sizeof hidg_desc, 93 .bDescriptorType = HID_DT_HID, 94 .bcdHID = 0x0101, 95 .bCountryCode = 0x00, 96 .bNumDescriptors = 0x1, 97 /*.desc[0].bDescriptorType = DYNAMIC */ 98 /*.desc[0].wDescriptorLenght = DYNAMIC */ 99 }; 100 101 /* Super-Speed Support */ 102 103 static struct usb_endpoint_descriptor hidg_ss_in_ep_desc = { 104 .bLength = USB_DT_ENDPOINT_SIZE, 105 .bDescriptorType = USB_DT_ENDPOINT, 106 .bEndpointAddress = USB_DIR_IN, 107 .bmAttributes = USB_ENDPOINT_XFER_INT, 108 /*.wMaxPacketSize = DYNAMIC */ 109 .bInterval = 4, /* FIXME: Add this field in the 110 * HID gadget configuration? 111 * (struct hidg_func_descriptor) 112 */ 113 }; 114 115 static struct usb_ss_ep_comp_descriptor hidg_ss_in_comp_desc = { 116 .bLength = sizeof(hidg_ss_in_comp_desc), 117 .bDescriptorType = USB_DT_SS_ENDPOINT_COMP, 118 119 /* .bMaxBurst = 0, */ 120 /* .bmAttributes = 0, */ 121 /* .wBytesPerInterval = DYNAMIC */ 122 }; 123 124 static struct usb_endpoint_descriptor hidg_ss_out_ep_desc = { 125 .bLength = USB_DT_ENDPOINT_SIZE, 126 .bDescriptorType = USB_DT_ENDPOINT, 127 .bEndpointAddress = USB_DIR_OUT, 128 .bmAttributes = USB_ENDPOINT_XFER_INT, 129 /*.wMaxPacketSize = DYNAMIC */ 130 .bInterval = 4, /* FIXME: Add this field in the 131 * HID gadget configuration? 132 * (struct hidg_func_descriptor) 133 */ 134 }; 135 136 static struct usb_ss_ep_comp_descriptor hidg_ss_out_comp_desc = { 137 .bLength = sizeof(hidg_ss_out_comp_desc), 138 .bDescriptorType = USB_DT_SS_ENDPOINT_COMP, 139 140 /* .bMaxBurst = 0, */ 141 /* .bmAttributes = 0, */ 142 /* .wBytesPerInterval = DYNAMIC */ 143 }; 144 145 static struct usb_descriptor_header *hidg_ss_descriptors[] = { 146 (struct usb_descriptor_header *)&hidg_interface_desc, 147 (struct usb_descriptor_header *)&hidg_desc, 148 (struct usb_descriptor_header *)&hidg_ss_in_ep_desc, 149 (struct usb_descriptor_header *)&hidg_ss_in_comp_desc, 150 (struct usb_descriptor_header *)&hidg_ss_out_ep_desc, 151 (struct usb_descriptor_header *)&hidg_ss_out_comp_desc, 152 NULL, 153 }; 154 155 /* High-Speed Support */ 156 157 static struct usb_endpoint_descriptor hidg_hs_in_ep_desc = { 158 .bLength = USB_DT_ENDPOINT_SIZE, 159 .bDescriptorType = USB_DT_ENDPOINT, 160 .bEndpointAddress = USB_DIR_IN, 161 .bmAttributes = USB_ENDPOINT_XFER_INT, 162 /*.wMaxPacketSize = DYNAMIC */ 163 .bInterval = 4, /* FIXME: Add this field in the 164 * HID gadget configuration? 165 * (struct hidg_func_descriptor) 166 */ 167 }; 168 169 static struct usb_endpoint_descriptor hidg_hs_out_ep_desc = { 170 .bLength = USB_DT_ENDPOINT_SIZE, 171 .bDescriptorType = USB_DT_ENDPOINT, 172 .bEndpointAddress = USB_DIR_OUT, 173 .bmAttributes = USB_ENDPOINT_XFER_INT, 174 /*.wMaxPacketSize = DYNAMIC */ 175 .bInterval = 4, /* FIXME: Add this field in the 176 * HID gadget configuration? 177 * (struct hidg_func_descriptor) 178 */ 179 }; 180 181 static struct usb_descriptor_header *hidg_hs_descriptors[] = { 182 (struct usb_descriptor_header *)&hidg_interface_desc, 183 (struct usb_descriptor_header *)&hidg_desc, 184 (struct usb_descriptor_header *)&hidg_hs_in_ep_desc, 185 (struct usb_descriptor_header *)&hidg_hs_out_ep_desc, 186 NULL, 187 }; 188 189 /* Full-Speed Support */ 190 191 static struct usb_endpoint_descriptor hidg_fs_in_ep_desc = { 192 .bLength = USB_DT_ENDPOINT_SIZE, 193 .bDescriptorType = USB_DT_ENDPOINT, 194 .bEndpointAddress = USB_DIR_IN, 195 .bmAttributes = USB_ENDPOINT_XFER_INT, 196 /*.wMaxPacketSize = DYNAMIC */ 197 .bInterval = 10, /* FIXME: Add this field in the 198 * HID gadget configuration? 199 * (struct hidg_func_descriptor) 200 */ 201 }; 202 203 static struct usb_endpoint_descriptor hidg_fs_out_ep_desc = { 204 .bLength = USB_DT_ENDPOINT_SIZE, 205 .bDescriptorType = USB_DT_ENDPOINT, 206 .bEndpointAddress = USB_DIR_OUT, 207 .bmAttributes = USB_ENDPOINT_XFER_INT, 208 /*.wMaxPacketSize = DYNAMIC */ 209 .bInterval = 10, /* FIXME: Add this field in the 210 * HID gadget configuration? 211 * (struct hidg_func_descriptor) 212 */ 213 }; 214 215 static struct usb_descriptor_header *hidg_fs_descriptors[] = { 216 (struct usb_descriptor_header *)&hidg_interface_desc, 217 (struct usb_descriptor_header *)&hidg_desc, 218 (struct usb_descriptor_header *)&hidg_fs_in_ep_desc, 219 (struct usb_descriptor_header *)&hidg_fs_out_ep_desc, 220 NULL, 221 }; 222 223 /*-------------------------------------------------------------------------*/ 224 /* Strings */ 225 226 #define CT_FUNC_HID_IDX 0 227 228 static struct usb_string ct_func_string_defs[] = { 229 [CT_FUNC_HID_IDX].s = "HID Interface", 230 {}, /* end of list */ 231 }; 232 233 static struct usb_gadget_strings ct_func_string_table = { 234 .language = 0x0409, /* en-US */ 235 .strings = ct_func_string_defs, 236 }; 237 238 static struct usb_gadget_strings *ct_func_strings[] = { 239 &ct_func_string_table, 240 NULL, 241 }; 242 243 /*-------------------------------------------------------------------------*/ 244 /* Char Device */ 245 246 static ssize_t f_hidg_read(struct file *file, char __user *buffer, 247 size_t count, loff_t *ptr) 248 { 249 struct f_hidg *hidg = file->private_data; 250 struct f_hidg_req_list *list; 251 struct usb_request *req; 252 unsigned long flags; 253 int ret; 254 255 if (!count) 256 return 0; 257 258 if (!access_ok(VERIFY_WRITE, buffer, count)) 259 return -EFAULT; 260 261 spin_lock_irqsave(&hidg->spinlock, flags); 262 263 #define READ_COND (!list_empty(&hidg->completed_out_req)) 264 265 /* wait for at least one buffer to complete */ 266 while (!READ_COND) { 267 spin_unlock_irqrestore(&hidg->spinlock, flags); 268 if (file->f_flags & O_NONBLOCK) 269 return -EAGAIN; 270 271 if (wait_event_interruptible(hidg->read_queue, READ_COND)) 272 return -ERESTARTSYS; 273 274 spin_lock_irqsave(&hidg->spinlock, flags); 275 } 276 277 /* pick the first one */ 278 list = list_first_entry(&hidg->completed_out_req, 279 struct f_hidg_req_list, list); 280 req = list->req; 281 count = min_t(unsigned int, count, req->actual - list->pos); 282 spin_unlock_irqrestore(&hidg->spinlock, flags); 283 284 /* copy to user outside spinlock */ 285 count -= copy_to_user(buffer, req->buf + list->pos, count); 286 list->pos += count; 287 288 /* 289 * if this request is completely handled and transfered to 290 * userspace, remove its entry from the list and requeue it 291 * again. Otherwise, we will revisit it again upon the next 292 * call, taking into account its current read position. 293 */ 294 if (list->pos == req->actual) { 295 spin_lock_irqsave(&hidg->spinlock, flags); 296 list_del(&list->list); 297 kfree(list); 298 spin_unlock_irqrestore(&hidg->spinlock, flags); 299 300 req->length = hidg->report_length; 301 ret = usb_ep_queue(hidg->out_ep, req, GFP_KERNEL); 302 if (ret < 0) 303 return ret; 304 } 305 306 return count; 307 } 308 309 static void f_hidg_req_complete(struct usb_ep *ep, struct usb_request *req) 310 { 311 struct f_hidg *hidg = (struct f_hidg *)ep->driver_data; 312 313 if (req->status != 0) { 314 ERROR(hidg->func.config->cdev, 315 "End Point Request ERROR: %d\n", req->status); 316 } 317 318 hidg->write_pending = 0; 319 wake_up(&hidg->write_queue); 320 } 321 322 static ssize_t f_hidg_write(struct file *file, const char __user *buffer, 323 size_t count, loff_t *offp) 324 { 325 struct f_hidg *hidg = file->private_data; 326 ssize_t status = -ENOMEM; 327 328 if (!access_ok(VERIFY_READ, buffer, count)) 329 return -EFAULT; 330 331 mutex_lock(&hidg->lock); 332 333 #define WRITE_COND (!hidg->write_pending) 334 335 /* write queue */ 336 while (!WRITE_COND) { 337 mutex_unlock(&hidg->lock); 338 if (file->f_flags & O_NONBLOCK) 339 return -EAGAIN; 340 341 if (wait_event_interruptible_exclusive( 342 hidg->write_queue, WRITE_COND)) 343 return -ERESTARTSYS; 344 345 mutex_lock(&hidg->lock); 346 } 347 348 count = min_t(unsigned, count, hidg->report_length); 349 status = copy_from_user(hidg->req->buf, buffer, count); 350 351 if (status != 0) { 352 ERROR(hidg->func.config->cdev, 353 "copy_from_user error\n"); 354 mutex_unlock(&hidg->lock); 355 return -EINVAL; 356 } 357 358 hidg->req->status = 0; 359 hidg->req->zero = 0; 360 hidg->req->length = count; 361 hidg->req->complete = f_hidg_req_complete; 362 hidg->req->context = hidg; 363 hidg->write_pending = 1; 364 365 status = usb_ep_queue(hidg->in_ep, hidg->req, GFP_ATOMIC); 366 if (status < 0) { 367 ERROR(hidg->func.config->cdev, 368 "usb_ep_queue error on int endpoint %zd\n", status); 369 hidg->write_pending = 0; 370 wake_up(&hidg->write_queue); 371 } else { 372 status = count; 373 } 374 375 mutex_unlock(&hidg->lock); 376 377 return status; 378 } 379 380 static unsigned int f_hidg_poll(struct file *file, poll_table *wait) 381 { 382 struct f_hidg *hidg = file->private_data; 383 unsigned int ret = 0; 384 385 poll_wait(file, &hidg->read_queue, wait); 386 poll_wait(file, &hidg->write_queue, wait); 387 388 if (WRITE_COND) 389 ret |= POLLOUT | POLLWRNORM; 390 391 if (READ_COND) 392 ret |= POLLIN | POLLRDNORM; 393 394 return ret; 395 } 396 397 #undef WRITE_COND 398 #undef READ_COND 399 400 static int f_hidg_release(struct inode *inode, struct file *fd) 401 { 402 fd->private_data = NULL; 403 return 0; 404 } 405 406 static int f_hidg_open(struct inode *inode, struct file *fd) 407 { 408 struct f_hidg *hidg = 409 container_of(inode->i_cdev, struct f_hidg, cdev); 410 411 fd->private_data = hidg; 412 413 return 0; 414 } 415 416 /*-------------------------------------------------------------------------*/ 417 /* usb_function */ 418 419 static inline struct usb_request *hidg_alloc_ep_req(struct usb_ep *ep, 420 unsigned length) 421 { 422 return alloc_ep_req(ep, length); 423 } 424 425 static void hidg_set_report_complete(struct usb_ep *ep, struct usb_request *req) 426 { 427 struct f_hidg *hidg = (struct f_hidg *) req->context; 428 struct f_hidg_req_list *req_list; 429 unsigned long flags; 430 431 req_list = kzalloc(sizeof(*req_list), GFP_ATOMIC); 432 if (!req_list) 433 return; 434 435 req_list->req = req; 436 437 spin_lock_irqsave(&hidg->spinlock, flags); 438 list_add_tail(&req_list->list, &hidg->completed_out_req); 439 spin_unlock_irqrestore(&hidg->spinlock, flags); 440 441 wake_up(&hidg->read_queue); 442 } 443 444 static int hidg_setup(struct usb_function *f, 445 const struct usb_ctrlrequest *ctrl) 446 { 447 struct f_hidg *hidg = func_to_hidg(f); 448 struct usb_composite_dev *cdev = f->config->cdev; 449 struct usb_request *req = cdev->req; 450 int status = 0; 451 __u16 value, length; 452 453 value = __le16_to_cpu(ctrl->wValue); 454 length = __le16_to_cpu(ctrl->wLength); 455 456 VDBG(cdev, 457 "%s crtl_request : bRequestType:0x%x bRequest:0x%x Value:0x%x\n", 458 __func__, ctrl->bRequestType, ctrl->bRequest, value); 459 460 switch ((ctrl->bRequestType << 8) | ctrl->bRequest) { 461 case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8 462 | HID_REQ_GET_REPORT): 463 VDBG(cdev, "get_report\n"); 464 465 /* send an empty report */ 466 length = min_t(unsigned, length, hidg->report_length); 467 memset(req->buf, 0x0, length); 468 469 goto respond; 470 break; 471 472 case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8 473 | HID_REQ_GET_PROTOCOL): 474 VDBG(cdev, "get_protocol\n"); 475 goto stall; 476 break; 477 478 case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8 479 | HID_REQ_SET_REPORT): 480 VDBG(cdev, "set_report | wLength=%d\n", ctrl->wLength); 481 goto stall; 482 break; 483 484 case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8 485 | HID_REQ_SET_PROTOCOL): 486 VDBG(cdev, "set_protocol\n"); 487 goto stall; 488 break; 489 490 case ((USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_INTERFACE) << 8 491 | USB_REQ_GET_DESCRIPTOR): 492 switch (value >> 8) { 493 case HID_DT_HID: 494 { 495 struct hid_descriptor hidg_desc_copy = hidg_desc; 496 497 VDBG(cdev, "USB_REQ_GET_DESCRIPTOR: HID\n"); 498 hidg_desc_copy.desc[0].bDescriptorType = HID_DT_REPORT; 499 hidg_desc_copy.desc[0].wDescriptorLength = 500 cpu_to_le16(hidg->report_desc_length); 501 502 length = min_t(unsigned short, length, 503 hidg_desc_copy.bLength); 504 memcpy(req->buf, &hidg_desc_copy, length); 505 goto respond; 506 break; 507 } 508 case HID_DT_REPORT: 509 VDBG(cdev, "USB_REQ_GET_DESCRIPTOR: REPORT\n"); 510 length = min_t(unsigned short, length, 511 hidg->report_desc_length); 512 memcpy(req->buf, hidg->report_desc, length); 513 goto respond; 514 break; 515 516 default: 517 VDBG(cdev, "Unknown descriptor request 0x%x\n", 518 value >> 8); 519 goto stall; 520 break; 521 } 522 break; 523 524 default: 525 VDBG(cdev, "Unknown request 0x%x\n", 526 ctrl->bRequest); 527 goto stall; 528 break; 529 } 530 531 stall: 532 return -EOPNOTSUPP; 533 534 respond: 535 req->zero = 0; 536 req->length = length; 537 status = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC); 538 if (status < 0) 539 ERROR(cdev, "usb_ep_queue error on ep0 %d\n", value); 540 return status; 541 } 542 543 static void hidg_disable(struct usb_function *f) 544 { 545 struct f_hidg *hidg = func_to_hidg(f); 546 struct f_hidg_req_list *list, *next; 547 548 usb_ep_disable(hidg->in_ep); 549 usb_ep_disable(hidg->out_ep); 550 551 list_for_each_entry_safe(list, next, &hidg->completed_out_req, list) { 552 list_del(&list->list); 553 kfree(list); 554 } 555 } 556 557 static int hidg_set_alt(struct usb_function *f, unsigned intf, unsigned alt) 558 { 559 struct usb_composite_dev *cdev = f->config->cdev; 560 struct f_hidg *hidg = func_to_hidg(f); 561 int i, status = 0; 562 563 VDBG(cdev, "hidg_set_alt intf:%d alt:%d\n", intf, alt); 564 565 if (hidg->in_ep != NULL) { 566 /* restart endpoint */ 567 usb_ep_disable(hidg->in_ep); 568 569 status = config_ep_by_speed(f->config->cdev->gadget, f, 570 hidg->in_ep); 571 if (status) { 572 ERROR(cdev, "config_ep_by_speed FAILED!\n"); 573 goto fail; 574 } 575 status = usb_ep_enable(hidg->in_ep); 576 if (status < 0) { 577 ERROR(cdev, "Enable IN endpoint FAILED!\n"); 578 goto fail; 579 } 580 hidg->in_ep->driver_data = hidg; 581 } 582 583 584 if (hidg->out_ep != NULL) { 585 /* restart endpoint */ 586 usb_ep_disable(hidg->out_ep); 587 588 status = config_ep_by_speed(f->config->cdev->gadget, f, 589 hidg->out_ep); 590 if (status) { 591 ERROR(cdev, "config_ep_by_speed FAILED!\n"); 592 goto fail; 593 } 594 status = usb_ep_enable(hidg->out_ep); 595 if (status < 0) { 596 ERROR(cdev, "Enable OUT endpoint FAILED!\n"); 597 goto fail; 598 } 599 hidg->out_ep->driver_data = hidg; 600 601 /* 602 * allocate a bunch of read buffers and queue them all at once. 603 */ 604 for (i = 0; i < hidg->qlen && status == 0; i++) { 605 struct usb_request *req = 606 hidg_alloc_ep_req(hidg->out_ep, 607 hidg->report_length); 608 if (req) { 609 req->complete = hidg_set_report_complete; 610 req->context = hidg; 611 status = usb_ep_queue(hidg->out_ep, req, 612 GFP_ATOMIC); 613 if (status) 614 ERROR(cdev, "%s queue req --> %d\n", 615 hidg->out_ep->name, status); 616 } else { 617 usb_ep_disable(hidg->out_ep); 618 status = -ENOMEM; 619 goto fail; 620 } 621 } 622 } 623 624 fail: 625 return status; 626 } 627 628 static const struct file_operations f_hidg_fops = { 629 .owner = THIS_MODULE, 630 .open = f_hidg_open, 631 .release = f_hidg_release, 632 .write = f_hidg_write, 633 .read = f_hidg_read, 634 .poll = f_hidg_poll, 635 .llseek = noop_llseek, 636 }; 637 638 static int hidg_bind(struct usb_configuration *c, struct usb_function *f) 639 { 640 struct usb_ep *ep; 641 struct f_hidg *hidg = func_to_hidg(f); 642 struct usb_string *us; 643 struct device *device; 644 int status; 645 dev_t dev; 646 647 /* maybe allocate device-global string IDs, and patch descriptors */ 648 us = usb_gstrings_attach(c->cdev, ct_func_strings, 649 ARRAY_SIZE(ct_func_string_defs)); 650 if (IS_ERR(us)) 651 return PTR_ERR(us); 652 hidg_interface_desc.iInterface = us[CT_FUNC_HID_IDX].id; 653 654 /* allocate instance-specific interface IDs, and patch descriptors */ 655 status = usb_interface_id(c, f); 656 if (status < 0) 657 goto fail; 658 hidg_interface_desc.bInterfaceNumber = status; 659 660 /* allocate instance-specific endpoints */ 661 status = -ENODEV; 662 ep = usb_ep_autoconfig(c->cdev->gadget, &hidg_fs_in_ep_desc); 663 if (!ep) 664 goto fail; 665 hidg->in_ep = ep; 666 667 ep = usb_ep_autoconfig(c->cdev->gadget, &hidg_fs_out_ep_desc); 668 if (!ep) 669 goto fail; 670 hidg->out_ep = ep; 671 672 /* preallocate request and buffer */ 673 status = -ENOMEM; 674 hidg->req = alloc_ep_req(hidg->in_ep, hidg->report_length); 675 if (!hidg->req) 676 goto fail; 677 678 /* set descriptor dynamic values */ 679 hidg_interface_desc.bInterfaceSubClass = hidg->bInterfaceSubClass; 680 hidg_interface_desc.bInterfaceProtocol = hidg->bInterfaceProtocol; 681 hidg_ss_in_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length); 682 hidg_ss_in_comp_desc.wBytesPerInterval = 683 cpu_to_le16(hidg->report_length); 684 hidg_hs_in_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length); 685 hidg_fs_in_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length); 686 hidg_ss_out_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length); 687 hidg_ss_out_comp_desc.wBytesPerInterval = 688 cpu_to_le16(hidg->report_length); 689 hidg_hs_out_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length); 690 hidg_fs_out_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length); 691 /* 692 * We can use hidg_desc struct here but we should not relay 693 * that its content won't change after returning from this function. 694 */ 695 hidg_desc.desc[0].bDescriptorType = HID_DT_REPORT; 696 hidg_desc.desc[0].wDescriptorLength = 697 cpu_to_le16(hidg->report_desc_length); 698 699 hidg_hs_in_ep_desc.bEndpointAddress = 700 hidg_fs_in_ep_desc.bEndpointAddress; 701 hidg_hs_out_ep_desc.bEndpointAddress = 702 hidg_fs_out_ep_desc.bEndpointAddress; 703 704 hidg_ss_in_ep_desc.bEndpointAddress = 705 hidg_fs_in_ep_desc.bEndpointAddress; 706 hidg_ss_out_ep_desc.bEndpointAddress = 707 hidg_fs_out_ep_desc.bEndpointAddress; 708 709 status = usb_assign_descriptors(f, hidg_fs_descriptors, 710 hidg_hs_descriptors, hidg_ss_descriptors, NULL); 711 if (status) 712 goto fail; 713 714 mutex_init(&hidg->lock); 715 spin_lock_init(&hidg->spinlock); 716 init_waitqueue_head(&hidg->write_queue); 717 init_waitqueue_head(&hidg->read_queue); 718 INIT_LIST_HEAD(&hidg->completed_out_req); 719 720 /* create char device */ 721 cdev_init(&hidg->cdev, &f_hidg_fops); 722 dev = MKDEV(major, hidg->minor); 723 status = cdev_add(&hidg->cdev, dev, 1); 724 if (status) 725 goto fail_free_descs; 726 727 device = device_create(hidg_class, NULL, dev, NULL, 728 "%s%d", "hidg", hidg->minor); 729 if (IS_ERR(device)) { 730 status = PTR_ERR(device); 731 goto del; 732 } 733 734 return 0; 735 del: 736 cdev_del(&hidg->cdev); 737 fail_free_descs: 738 usb_free_all_descriptors(f); 739 fail: 740 ERROR(f->config->cdev, "hidg_bind FAILED\n"); 741 if (hidg->req != NULL) 742 free_ep_req(hidg->in_ep, hidg->req); 743 744 return status; 745 } 746 747 static inline int hidg_get_minor(void) 748 { 749 int ret; 750 751 ret = ida_simple_get(&hidg_ida, 0, 0, GFP_KERNEL); 752 if (ret >= HIDG_MINORS) { 753 ida_simple_remove(&hidg_ida, ret); 754 ret = -ENODEV; 755 } 756 757 return ret; 758 } 759 760 static inline struct f_hid_opts *to_f_hid_opts(struct config_item *item) 761 { 762 return container_of(to_config_group(item), struct f_hid_opts, 763 func_inst.group); 764 } 765 766 static void hid_attr_release(struct config_item *item) 767 { 768 struct f_hid_opts *opts = to_f_hid_opts(item); 769 770 usb_put_function_instance(&opts->func_inst); 771 } 772 773 static struct configfs_item_operations hidg_item_ops = { 774 .release = hid_attr_release, 775 }; 776 777 #define F_HID_OPT(name, prec, limit) \ 778 static ssize_t f_hid_opts_##name##_show(struct config_item *item, char *page)\ 779 { \ 780 struct f_hid_opts *opts = to_f_hid_opts(item); \ 781 int result; \ 782 \ 783 mutex_lock(&opts->lock); \ 784 result = sprintf(page, "%d\n", opts->name); \ 785 mutex_unlock(&opts->lock); \ 786 \ 787 return result; \ 788 } \ 789 \ 790 static ssize_t f_hid_opts_##name##_store(struct config_item *item, \ 791 const char *page, size_t len) \ 792 { \ 793 struct f_hid_opts *opts = to_f_hid_opts(item); \ 794 int ret; \ 795 u##prec num; \ 796 \ 797 mutex_lock(&opts->lock); \ 798 if (opts->refcnt) { \ 799 ret = -EBUSY; \ 800 goto end; \ 801 } \ 802 \ 803 ret = kstrtou##prec(page, 0, &num); \ 804 if (ret) \ 805 goto end; \ 806 \ 807 if (num > limit) { \ 808 ret = -EINVAL; \ 809 goto end; \ 810 } \ 811 opts->name = num; \ 812 ret = len; \ 813 \ 814 end: \ 815 mutex_unlock(&opts->lock); \ 816 return ret; \ 817 } \ 818 \ 819 CONFIGFS_ATTR(f_hid_opts_, name) 820 821 F_HID_OPT(subclass, 8, 255); 822 F_HID_OPT(protocol, 8, 255); 823 F_HID_OPT(report_length, 16, 65535); 824 825 static ssize_t f_hid_opts_report_desc_show(struct config_item *item, char *page) 826 { 827 struct f_hid_opts *opts = to_f_hid_opts(item); 828 int result; 829 830 mutex_lock(&opts->lock); 831 result = opts->report_desc_length; 832 memcpy(page, opts->report_desc, opts->report_desc_length); 833 mutex_unlock(&opts->lock); 834 835 return result; 836 } 837 838 static ssize_t f_hid_opts_report_desc_store(struct config_item *item, 839 const char *page, size_t len) 840 { 841 struct f_hid_opts *opts = to_f_hid_opts(item); 842 int ret = -EBUSY; 843 char *d; 844 845 mutex_lock(&opts->lock); 846 847 if (opts->refcnt) 848 goto end; 849 if (len > PAGE_SIZE) { 850 ret = -ENOSPC; 851 goto end; 852 } 853 d = kmemdup(page, len, GFP_KERNEL); 854 if (!d) { 855 ret = -ENOMEM; 856 goto end; 857 } 858 kfree(opts->report_desc); 859 opts->report_desc = d; 860 opts->report_desc_length = len; 861 opts->report_desc_alloc = true; 862 ret = len; 863 end: 864 mutex_unlock(&opts->lock); 865 return ret; 866 } 867 868 CONFIGFS_ATTR(f_hid_opts_, report_desc); 869 870 static ssize_t f_hid_opts_dev_show(struct config_item *item, char *page) 871 { 872 struct f_hid_opts *opts = to_f_hid_opts(item); 873 874 return sprintf(page, "%d:%d\n", major, opts->minor); 875 } 876 877 CONFIGFS_ATTR_RO(f_hid_opts_, dev); 878 879 static struct configfs_attribute *hid_attrs[] = { 880 &f_hid_opts_attr_subclass, 881 &f_hid_opts_attr_protocol, 882 &f_hid_opts_attr_report_length, 883 &f_hid_opts_attr_report_desc, 884 &f_hid_opts_attr_dev, 885 NULL, 886 }; 887 888 static struct config_item_type hid_func_type = { 889 .ct_item_ops = &hidg_item_ops, 890 .ct_attrs = hid_attrs, 891 .ct_owner = THIS_MODULE, 892 }; 893 894 static inline void hidg_put_minor(int minor) 895 { 896 ida_simple_remove(&hidg_ida, minor); 897 } 898 899 static void hidg_free_inst(struct usb_function_instance *f) 900 { 901 struct f_hid_opts *opts; 902 903 opts = container_of(f, struct f_hid_opts, func_inst); 904 905 mutex_lock(&hidg_ida_lock); 906 907 hidg_put_minor(opts->minor); 908 if (ida_is_empty(&hidg_ida)) 909 ghid_cleanup(); 910 911 mutex_unlock(&hidg_ida_lock); 912 913 if (opts->report_desc_alloc) 914 kfree(opts->report_desc); 915 916 kfree(opts); 917 } 918 919 static struct usb_function_instance *hidg_alloc_inst(void) 920 { 921 struct f_hid_opts *opts; 922 struct usb_function_instance *ret; 923 int status = 0; 924 925 opts = kzalloc(sizeof(*opts), GFP_KERNEL); 926 if (!opts) 927 return ERR_PTR(-ENOMEM); 928 mutex_init(&opts->lock); 929 opts->func_inst.free_func_inst = hidg_free_inst; 930 ret = &opts->func_inst; 931 932 mutex_lock(&hidg_ida_lock); 933 934 if (ida_is_empty(&hidg_ida)) { 935 status = ghid_setup(NULL, HIDG_MINORS); 936 if (status) { 937 ret = ERR_PTR(status); 938 kfree(opts); 939 goto unlock; 940 } 941 } 942 943 opts->minor = hidg_get_minor(); 944 if (opts->minor < 0) { 945 ret = ERR_PTR(opts->minor); 946 kfree(opts); 947 if (ida_is_empty(&hidg_ida)) 948 ghid_cleanup(); 949 goto unlock; 950 } 951 config_group_init_type_name(&opts->func_inst.group, "", &hid_func_type); 952 953 unlock: 954 mutex_unlock(&hidg_ida_lock); 955 return ret; 956 } 957 958 static void hidg_free(struct usb_function *f) 959 { 960 struct f_hidg *hidg; 961 struct f_hid_opts *opts; 962 963 hidg = func_to_hidg(f); 964 opts = container_of(f->fi, struct f_hid_opts, func_inst); 965 kfree(hidg->report_desc); 966 kfree(hidg); 967 mutex_lock(&opts->lock); 968 --opts->refcnt; 969 mutex_unlock(&opts->lock); 970 } 971 972 static void hidg_unbind(struct usb_configuration *c, struct usb_function *f) 973 { 974 struct f_hidg *hidg = func_to_hidg(f); 975 976 device_destroy(hidg_class, MKDEV(major, hidg->minor)); 977 cdev_del(&hidg->cdev); 978 979 /* disable/free request and end point */ 980 usb_ep_disable(hidg->in_ep); 981 free_ep_req(hidg->in_ep, hidg->req); 982 983 usb_free_all_descriptors(f); 984 } 985 986 static struct usb_function *hidg_alloc(struct usb_function_instance *fi) 987 { 988 struct f_hidg *hidg; 989 struct f_hid_opts *opts; 990 991 /* allocate and initialize one new instance */ 992 hidg = kzalloc(sizeof(*hidg), GFP_KERNEL); 993 if (!hidg) 994 return ERR_PTR(-ENOMEM); 995 996 opts = container_of(fi, struct f_hid_opts, func_inst); 997 998 mutex_lock(&opts->lock); 999 ++opts->refcnt; 1000 1001 hidg->minor = opts->minor; 1002 hidg->bInterfaceSubClass = opts->subclass; 1003 hidg->bInterfaceProtocol = opts->protocol; 1004 hidg->report_length = opts->report_length; 1005 hidg->report_desc_length = opts->report_desc_length; 1006 if (opts->report_desc) { 1007 hidg->report_desc = kmemdup(opts->report_desc, 1008 opts->report_desc_length, 1009 GFP_KERNEL); 1010 if (!hidg->report_desc) { 1011 kfree(hidg); 1012 mutex_unlock(&opts->lock); 1013 return ERR_PTR(-ENOMEM); 1014 } 1015 } 1016 1017 mutex_unlock(&opts->lock); 1018 1019 hidg->func.name = "hid"; 1020 hidg->func.bind = hidg_bind; 1021 hidg->func.unbind = hidg_unbind; 1022 hidg->func.set_alt = hidg_set_alt; 1023 hidg->func.disable = hidg_disable; 1024 hidg->func.setup = hidg_setup; 1025 hidg->func.free_func = hidg_free; 1026 1027 /* this could me made configurable at some point */ 1028 hidg->qlen = 4; 1029 1030 return &hidg->func; 1031 } 1032 1033 DECLARE_USB_FUNCTION_INIT(hid, hidg_alloc_inst, hidg_alloc); 1034 MODULE_LICENSE("GPL"); 1035 MODULE_AUTHOR("Fabien Chouteau"); 1036 1037 int ghid_setup(struct usb_gadget *g, int count) 1038 { 1039 int status; 1040 dev_t dev; 1041 1042 hidg_class = class_create(THIS_MODULE, "hidg"); 1043 if (IS_ERR(hidg_class)) { 1044 status = PTR_ERR(hidg_class); 1045 hidg_class = NULL; 1046 return status; 1047 } 1048 1049 status = alloc_chrdev_region(&dev, 0, count, "hidg"); 1050 if (status) { 1051 class_destroy(hidg_class); 1052 hidg_class = NULL; 1053 return status; 1054 } 1055 1056 major = MAJOR(dev); 1057 minors = count; 1058 1059 return 0; 1060 } 1061 1062 void ghid_cleanup(void) 1063 { 1064 if (major) { 1065 unregister_chrdev_region(MKDEV(major, 0), minors); 1066 major = minors = 0; 1067 } 1068 1069 class_destroy(hidg_class); 1070 hidg_class = NULL; 1071 } 1072