drivers/usb/gadget/f_uvc.c

   1 /*
   2  *      uvc_gadget.c  --  USB Video Class Gadget driver
   3  *
   4  *      Copyright (C) 2009-2010
   5  *          Laurent Pinchart (laurent.pinchart@ideasonboard.com)
   6  *
   7  *      This program is free software; you can redistribute it and/or modify
   8  *      it under the terms of the GNU General Public License as published by
   9  *      the Free Software Foundation; either version 2 of the License, or
  10  *      (at your option) any later version.
  11  */
  12
  13 #include <linux/kernel.h>
  14 #include <linux/device.h>
  15 #include <linux/errno.h>
  16 #include <linux/fs.h>
  17 #include <linux/list.h>
  18 #include <linux/mutex.h>
  19 #include <linux/string.h>
  20 #include <linux/usb/ch9.h>
  21 #include <linux/usb/gadget.h>
  22 #include <linux/usb/video.h>
  23 #include <linux/vmalloc.h>
  24 #include <linux/wait.h>
  25
  26 #include <media/v4l2-dev.h>
  27 #include <media/v4l2-event.h>
  28
  29 #include "uvc.h"
  30
  31 unsigned int uvc_gadget_trace_param;
  32
  33 /*-------------------------------------------------------------------------*/
  34
  35 /* module parameters specific to the Video streaming endpoint */
  36 static unsigned int streaming_interval = 1;
  37 module_param(streaming_interval, uint, S_IRUGO|S_IWUSR);
  38 MODULE_PARM_DESC(streaming_interval, "1 - 16");
  39
  40 static unsigned int streaming_maxpacket = 1024;
  41 module_param(streaming_maxpacket, uint, S_IRUGO|S_IWUSR);
  42 MODULE_PARM_DESC(streaming_maxpacket, "1 - 1023 (FS), 1 - 3072 (hs/ss)");
  43
  44 static unsigned int streaming_maxburst;
  45 module_param(streaming_maxburst, uint, S_IRUGO|S_IWUSR);
  46 MODULE_PARM_DESC(streaming_maxburst, "0 - 15 (ss only)");
  47
  48 /* --------------------------------------------------------------------------
  49  * Function descriptors
  50  */
  51
  52 /* string IDs are assigned dynamically */
  53
  54 #define UVC_STRING_CONTROL_IDX                  0
  55 #define UVC_STRING_STREAMING_IDX                1
  56
  57 static struct usb_string uvc_en_us_strings[] = {
  58         [UVC_STRING_CONTROL_IDX].s = "UVC Camera",
  59         [UVC_STRING_STREAMING_IDX].s = "Video Streaming",
  60         {  }
  61 };
  62
  63 static struct usb_gadget_strings uvc_stringtab = {
  64         .language = 0x0409,     /* en-us */
  65         .strings = uvc_en_us_strings,
  66 };
  67
  68 static struct usb_gadget_strings *uvc_function_strings[] = {
  69         &uvc_stringtab,
  70         NULL,
  71 };
  72
  73 #define UVC_INTF_VIDEO_CONTROL                  0
  74 #define UVC_INTF_VIDEO_STREAMING                1
  75
  76 #define UVC_STATUS_MAX_PACKET_SIZE              16      /* 16 bytes status */
  77
  78 static struct usb_interface_assoc_descriptor uvc_iad __initdata = {
  79         .bLength                = sizeof(uvc_iad),
  80         .bDescriptorType        = USB_DT_INTERFACE_ASSOCIATION,
  81         .bFirstInterface        = 0,
  82         .bInterfaceCount        = 2,
  83         .bFunctionClass         = USB_CLASS_VIDEO,
  84         .bFunctionSubClass      = UVC_SC_VIDEO_INTERFACE_COLLECTION,
  85         .bFunctionProtocol      = 0x00,
  86         .iFunction              = 0,
  87 };
  88
  89 static struct usb_interface_descriptor uvc_control_intf __initdata = {
  90         .bLength                = USB_DT_INTERFACE_SIZE,
  91         .bDescriptorType        = USB_DT_INTERFACE,
  92         .bInterfaceNumber       = UVC_INTF_VIDEO_CONTROL,
  93         .bAlternateSetting      = 0,
  94         .bNumEndpoints          = 1,
  95         .bInterfaceClass        = USB_CLASS_VIDEO,
  96         .bInterfaceSubClass     = UVC_SC_VIDEOCONTROL,
  97         .bInterfaceProtocol     = 0x00,
  98         .iInterface             = 0,
  99 };
 100
 101 static struct usb_endpoint_descriptor uvc_control_ep __initdata = {
 102         .bLength                = USB_DT_ENDPOINT_SIZE,
 103         .bDescriptorType        = USB_DT_ENDPOINT,
 104         .bEndpointAddress       = USB_DIR_IN,
 105         .bmAttributes           = USB_ENDPOINT_XFER_INT,
 106         .wMaxPacketSize         = cpu_to_le16(UVC_STATUS_MAX_PACKET_SIZE),
 107         .bInterval              = 8,
 108 };
 109
 110 static struct usb_ss_ep_comp_descriptor uvc_ss_control_comp __initdata = {
 111         .bLength                = sizeof(uvc_ss_control_comp),
 112         .bDescriptorType        = USB_DT_SS_ENDPOINT_COMP,
 113         /* The following 3 values can be tweaked if necessary. */
 114         .bMaxBurst              = 0,
 115         .bmAttributes           = 0,
 116         .wBytesPerInterval      = cpu_to_le16(UVC_STATUS_MAX_PACKET_SIZE),
 117 };
 118
 119 static struct uvc_control_endpoint_descriptor uvc_control_cs_ep __initdata = {
 120         .bLength                = UVC_DT_CONTROL_ENDPOINT_SIZE,
 121         .bDescriptorType        = USB_DT_CS_ENDPOINT,
 122         .bDescriptorSubType     = UVC_EP_INTERRUPT,
 123         .wMaxTransferSize       = cpu_to_le16(UVC_STATUS_MAX_PACKET_SIZE),
 124 };
 125
 126 static struct usb_interface_descriptor uvc_streaming_intf_alt0 __initdata = {
 127         .bLength                = USB_DT_INTERFACE_SIZE,
 128         .bDescriptorType        = USB_DT_INTERFACE,
 129         .bInterfaceNumber       = UVC_INTF_VIDEO_STREAMING,
 130         .bAlternateSetting      = 0,
 131         .bNumEndpoints          = 0,
 132         .bInterfaceClass        = USB_CLASS_VIDEO,
 133         .bInterfaceSubClass     = UVC_SC_VIDEOSTREAMING,
 134         .bInterfaceProtocol     = 0x00,
 135         .iInterface             = 0,
 136 };
 137
 138 static struct usb_interface_descriptor uvc_streaming_intf_alt1 __initdata = {
 139         .bLength                = USB_DT_INTERFACE_SIZE,
 140         .bDescriptorType        = USB_DT_INTERFACE,
 141         .bInterfaceNumber       = UVC_INTF_VIDEO_STREAMING,
 142         .bAlternateSetting      = 1,
 143         .bNumEndpoints          = 1,
 144         .bInterfaceClass        = USB_CLASS_VIDEO,
 145         .bInterfaceSubClass     = UVC_SC_VIDEOSTREAMING,
 146         .bInterfaceProtocol     = 0x00,
 147         .iInterface             = 0,
 148 };
 149
 150 static struct usb_endpoint_descriptor uvc_fs_streaming_ep __initdata = {
 151         .bLength                = USB_DT_ENDPOINT_SIZE,
 152         .bDescriptorType        = USB_DT_ENDPOINT,
 153         .bEndpointAddress       = USB_DIR_IN,
 154         .bmAttributes           = USB_ENDPOINT_SYNC_ASYNC
 155                                 | USB_ENDPOINT_XFER_ISOC,
 156         /* The wMaxPacketSize and bInterval values will be initialized from
 157          * module parameters.
 158          */
 159 };
 160
 161 static struct usb_endpoint_descriptor uvc_hs_streaming_ep __initdata = {
 162         .bLength                = USB_DT_ENDPOINT_SIZE,
 163         .bDescriptorType        = USB_DT_ENDPOINT,
 164         .bEndpointAddress       = USB_DIR_IN,
 165         .bmAttributes           = USB_ENDPOINT_SYNC_ASYNC
 166                                 | USB_ENDPOINT_XFER_ISOC,
 167         /* The wMaxPacketSize and bInterval values will be initialized from
 168          * module parameters.
 169          */
 170 };
 171
 172 static struct usb_endpoint_descriptor uvc_ss_streaming_ep __initdata = {
 173         .bLength                = USB_DT_ENDPOINT_SIZE,
 174         .bDescriptorType        = USB_DT_ENDPOINT,
 175
 176         .bEndpointAddress       = USB_DIR_IN,
 177         .bmAttributes           = USB_ENDPOINT_SYNC_ASYNC
 178                                 | USB_ENDPOINT_XFER_ISOC,
 179         /* The wMaxPacketSize and bInterval values will be initialized from
 180          * module parameters.
 181          */
 182 };
 183
 184 static struct usb_ss_ep_comp_descriptor uvc_ss_streaming_comp __initdata = {
 185         .bLength                = sizeof(uvc_ss_streaming_comp),
 186         .bDescriptorType        = USB_DT_SS_ENDPOINT_COMP,
 187         /* The bMaxBurst, bmAttributes and wBytesPerInterval values will be
 188          * initialized from module parameters.
 189          */
 190 };
 191
 192 static const struct usb_descriptor_header * const uvc_fs_streaming[] = {
 193         (struct usb_descriptor_header *) &uvc_streaming_intf_alt1,
 194         (struct usb_descriptor_header *) &uvc_fs_streaming_ep,
 195         NULL,
 196 };
 197
 198 static const struct usb_descriptor_header * const uvc_hs_streaming[] = {
 199         (struct usb_descriptor_header *) &uvc_streaming_intf_alt1,
 200         (struct usb_descriptor_header *) &uvc_hs_streaming_ep,
 201         NULL,
 202 };
 203
 204 static const struct usb_descriptor_header * const uvc_ss_streaming[] = {
 205         (struct usb_descriptor_header *) &uvc_streaming_intf_alt1,
 206         (struct usb_descriptor_header *) &uvc_ss_streaming_ep,
 207         (struct usb_descriptor_header *) &uvc_ss_streaming_comp,
 208         NULL,
 209 };
 210
 211 /* --------------------------------------------------------------------------
 212  * Control requests
 213  */
 214
 215 static void
 216 uvc_function_ep0_complete(struct usb_ep *ep, struct usb_request *req)
 217 {
 218         struct uvc_device *uvc = req->context;
 219         struct v4l2_event v4l2_event;
 220         struct uvc_event *uvc_event = (void *)&v4l2_event.u.data;
 221
 222         if (uvc->event_setup_out) {
 223                 uvc->event_setup_out = 0;
 224
 225                 memset(&v4l2_event, 0, sizeof(v4l2_event));
 226                 v4l2_event.type = UVC_EVENT_DATA;
 227                 uvc_event->data.length = req->actual;
 228                 memcpy(&uvc_event->data.data, req->buf, req->actual);
 229                 v4l2_event_queue(uvc->vdev, &v4l2_event);
 230         }
 231 }
 232
 233 static int
 234 uvc_function_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
 235 {
 236         struct uvc_device *uvc = to_uvc(f);
 237         struct v4l2_event v4l2_event;
 238         struct uvc_event *uvc_event = (void *)&v4l2_event.u.data;
 239
 240         /* printk(KERN_INFO "setup request %02x %02x value %04x index %04x %04x\n",
 241          *      ctrl->bRequestType, ctrl->bRequest, le16_to_cpu(ctrl->wValue),
 242          *      le16_to_cpu(ctrl->wIndex), le16_to_cpu(ctrl->wLength));
 243          */
 244
 245         if ((ctrl->bRequestType & USB_TYPE_MASK) != USB_TYPE_CLASS) {
 246                 INFO(f->config->cdev, "invalid request type\n");
 247                 return -EINVAL;
 248         }
 249
 250         /* Stall too big requests. */
 251         if (le16_to_cpu(ctrl->wLength) > UVC_MAX_REQUEST_SIZE)
 252                 return -EINVAL;
 253
 254         memset(&v4l2_event, 0, sizeof(v4l2_event));
 255         v4l2_event.type = UVC_EVENT_SETUP;
 256         memcpy(&uvc_event->req, ctrl, sizeof(uvc_event->req));
 257         v4l2_event_queue(uvc->vdev, &v4l2_event);
 258
 259         return 0;
 260 }
 261
 262 void uvc_function_setup_continue(struct uvc_device *uvc)
 263 {
 264         struct usb_composite_dev *cdev = uvc->func.config->cdev;
 265
 266         usb_composite_setup_continue(cdev);
 267 }
 268
 269 static int
 270 uvc_function_get_alt(struct usb_function *f, unsigned interface)
 271 {
 272         struct uvc_device *uvc = to_uvc(f);
 273
 274         INFO(f->config->cdev, "uvc_function_get_alt(%u)\n", interface);
 275
 276         if (interface == uvc->control_intf)
 277                 return 0;
 278         else if (interface != uvc->streaming_intf)
 279                 return -EINVAL;
 280         else
 281                 return uvc->state == UVC_STATE_STREAMING ? 1 : 0;
 282 }
 283
 284 static int
 285 uvc_function_set_alt(struct usb_function *f, unsigned interface, unsigned alt)
 286 {
 287         struct uvc_device *uvc = to_uvc(f);
 288         struct v4l2_event v4l2_event;
 289         struct uvc_event *uvc_event = (void *)&v4l2_event.u.data;
 290         int ret;
 291
 292         INFO(f->config->cdev, "uvc_function_set_alt(%u, %u)\n", interface, alt);
 293
 294         if (interface == uvc->control_intf) {
 295                 if (alt)
 296                         return -EINVAL;
 297
 298                 if (uvc->state == UVC_STATE_DISCONNECTED) {
 299                         memset(&v4l2_event, 0, sizeof(v4l2_event));
 300                         v4l2_event.type = UVC_EVENT_CONNECT;
 301                         uvc_event->speed = f->config->cdev->gadget->speed;
 302                         v4l2_event_queue(uvc->vdev, &v4l2_event);
 303
 304                         uvc->state = UVC_STATE_CONNECTED;
 305                 }
 306
 307                 return 0;
 308         }
 309
 310         if (interface != uvc->streaming_intf)
 311                 return -EINVAL;
 312
 313         /* TODO
 314         if (usb_endpoint_xfer_bulk(&uvc->desc.vs_ep))
 315                 return alt ? -EINVAL : 0;
 316         */
 317
 318         switch (alt) {
 319         case 0:
 320                 if (uvc->state != UVC_STATE_STREAMING)
 321                         return 0;
 322
 323                 if (uvc->video.ep)
 324                         usb_ep_disable(uvc->video.ep);
 325
 326                 memset(&v4l2_event, 0, sizeof(v4l2_event));
 327                 v4l2_event.type = UVC_EVENT_STREAMOFF;
 328                 v4l2_event_queue(uvc->vdev, &v4l2_event);
 329
 330                 uvc->state = UVC_STATE_CONNECTED;
 331                 return 0;
 332
 333         case 1:
 334                 if (uvc->state != UVC_STATE_CONNECTED)
 335                         return 0;
 336
 337                 if (uvc->video.ep) {
 338                         ret = config_ep_by_speed(f->config->cdev->gadget,
 339                                         &(uvc->func), uvc->video.ep);
 340                         if (ret)
 341                                 return ret;
 342                         usb_ep_enable(uvc->video.ep);
 343                 }
 344
 345                 memset(&v4l2_event, 0, sizeof(v4l2_event));
 346                 v4l2_event.type = UVC_EVENT_STREAMON;
 347                 v4l2_event_queue(uvc->vdev, &v4l2_event);
 348                 return USB_GADGET_DELAYED_STATUS;
 349
 350         default:
 351                 return -EINVAL;
 352         }
 353 }
 354
 355 static void
 356 uvc_function_disable(struct usb_function *f)
 357 {
 358         struct uvc_device *uvc = to_uvc(f);
 359         struct v4l2_event v4l2_event;
 360
 361         INFO(f->config->cdev, "uvc_function_disable\n");
 362
 363         memset(&v4l2_event, 0, sizeof(v4l2_event));
 364         v4l2_event.type = UVC_EVENT_DISCONNECT;
 365         v4l2_event_queue(uvc->vdev, &v4l2_event);
 366
 367         uvc->state = UVC_STATE_DISCONNECTED;
 368 }
 369
 370 /* --------------------------------------------------------------------------
 371  * Connection / disconnection
 372  */
 373
 374 void
 375 uvc_function_connect(struct uvc_device *uvc)
 376 {
 377         struct usb_composite_dev *cdev = uvc->func.config->cdev;
 378         int ret;
 379
 380         if ((ret = usb_function_activate(&uvc->func)) < 0)
 381                 INFO(cdev, "UVC connect failed with %d\n", ret);
 382 }
 383
 384 void
 385 uvc_function_disconnect(struct uvc_device *uvc)
 386 {
 387         struct usb_composite_dev *cdev = uvc->func.config->cdev;
 388         int ret;
 389
 390         if ((ret = usb_function_deactivate(&uvc->func)) < 0)
 391                 INFO(cdev, "UVC disconnect failed with %d\n", ret);
 392 }
 393
 394 /* --------------------------------------------------------------------------
 395  * USB probe and disconnect
 396  */
 397
 398 static int
 399 uvc_register_video(struct uvc_device *uvc)
 400 {
 401         struct usb_composite_dev *cdev = uvc->func.config->cdev;
 402         struct video_device *video;
 403
 404         /* TODO reference counting. */
 405         video = video_device_alloc();
 406         if (video == NULL)
 407                 return -ENOMEM;
 408
 409         video->parent = &cdev->gadget->dev;
 410         video->fops = &uvc_v4l2_fops;
 411         video->release = video_device_release;
 412         strlcpy(video->name, cdev->gadget->name, sizeof(video->name));
 413
 414         uvc->vdev = video;
 415         video_set_drvdata(video, uvc);
 416
 417         return video_register_device(video, VFL_TYPE_GRABBER, -1);
 418 }
 419
 420 #define UVC_COPY_DESCRIPTOR(mem, dst, desc) \
 421         do { \
 422                 memcpy(mem, desc, (desc)->bLength); \
 423                 *(dst)++ = mem; \
 424                 mem += (desc)->bLength; \
 425         } while (0);
 426
 427 #define UVC_COPY_DESCRIPTORS(mem, dst, src) \
 428         do { \
 429                 const struct usb_descriptor_header * const *__src; \
 430                 for (__src = src; *__src; ++__src) { \
 431                         memcpy(mem, *__src, (*__src)->bLength); \
 432                         *dst++ = mem; \
 433                         mem += (*__src)->bLength; \
 434                 } \
 435         } while (0)
 436
 437 static struct usb_descriptor_header ** __init
 438 uvc_copy_descriptors(struct uvc_device *uvc, enum usb_device_speed speed)
 439 {
 440         struct uvc_input_header_descriptor *uvc_streaming_header;
 441         struct uvc_header_descriptor *uvc_control_header;
 442         const struct uvc_descriptor_header * const *uvc_control_desc;
 443         const struct uvc_descriptor_header * const *uvc_streaming_cls;
 444         const struct usb_descriptor_header * const *uvc_streaming_std;
 445         const struct usb_descriptor_header * const *src;
 446         struct usb_descriptor_header **dst;
 447         struct usb_descriptor_header **hdr;
 448         unsigned int control_size;
 449         unsigned int streaming_size;
 450         unsigned int n_desc;
 451         unsigned int bytes;
 452         void *mem;
 453
 454         switch (speed) {
 455         case USB_SPEED_SUPER:
 456                 uvc_control_desc = uvc->desc.ss_control;
 457                 uvc_streaming_cls = uvc->desc.ss_streaming;
 458                 uvc_streaming_std = uvc_ss_streaming;
 459                 break;
 460
 461         case USB_SPEED_HIGH:
 462                 uvc_control_desc = uvc->desc.fs_control;
 463                 uvc_streaming_cls = uvc->desc.hs_streaming;
 464                 uvc_streaming_std = uvc_hs_streaming;
 465                 break;
 466
 467         case USB_SPEED_FULL:
 468         default:
 469                 uvc_control_desc = uvc->desc.fs_control;
 470                 uvc_streaming_cls = uvc->desc.fs_streaming;
 471                 uvc_streaming_std = uvc_fs_streaming;
 472                 break;
 473         }
 474
 475         /* Descriptors layout
 476          *
 477          * uvc_iad
 478          * uvc_control_intf
 479          * Class-specific UVC control descriptors
 480          * uvc_control_ep
 481          * uvc_control_cs_ep
 482          * uvc_ss_control_comp (for SS only)
 483          * uvc_streaming_intf_alt0
 484          * Class-specific UVC streaming descriptors
 485          * uvc_{fs|hs}_streaming
 486          */
 487
 488         /* Count descriptors and compute their size. */
 489         control_size = 0;
 490         streaming_size = 0;
 491         bytes = uvc_iad.bLength + uvc_control_intf.bLength
 492               + uvc_control_ep.bLength + uvc_control_cs_ep.bLength
 493               + uvc_streaming_intf_alt0.bLength;
 494
 495         if (speed == USB_SPEED_SUPER) {
 496                 bytes += uvc_ss_control_comp.bLength;
 497                 n_desc = 6;
 498         } else {
 499                 n_desc = 5;
 500         }
 501
 502         for (src = (const struct usb_descriptor_header **)uvc_control_desc;
 503              *src; ++src) {
 504                 control_size += (*src)->bLength;
 505                 bytes += (*src)->bLength;
 506                 n_desc++;
 507         }
 508         for (src = (const struct usb_descriptor_header **)uvc_streaming_cls;
 509              *src; ++src) {
 510                 streaming_size += (*src)->bLength;
 511                 bytes += (*src)->bLength;
 512                 n_desc++;
 513         }
 514         for (src = uvc_streaming_std; *src; ++src) {
 515                 bytes += (*src)->bLength;
 516                 n_desc++;
 517         }
 518
 519         mem = kmalloc((n_desc + 1) * sizeof(*src) + bytes, GFP_KERNEL);
 520         if (mem == NULL)
 521                 return NULL;
 522
 523         hdr = mem;
 524         dst = mem;
 525         mem += (n_desc + 1) * sizeof(*src);
 526
 527         /* Copy the descriptors. */
 528         UVC_COPY_DESCRIPTOR(mem, dst, &uvc_iad);
 529         UVC_COPY_DESCRIPTOR(mem, dst, &uvc_control_intf);
 530
 531         uvc_control_header = mem;
 532         UVC_COPY_DESCRIPTORS(mem, dst,
 533                 (const struct usb_descriptor_header **)uvc_control_desc);
 534         uvc_control_header->wTotalLength = cpu_to_le16(control_size);
 535         uvc_control_header->bInCollection = 1;
 536         uvc_control_header->baInterfaceNr[0] = uvc->streaming_intf;
 537
 538         UVC_COPY_DESCRIPTOR(mem, dst, &uvc_control_ep);
 539         if (speed == USB_SPEED_SUPER)
 540                 UVC_COPY_DESCRIPTOR(mem, dst, &uvc_ss_control_comp);
 541
 542         UVC_COPY_DESCRIPTOR(mem, dst, &uvc_control_cs_ep);
 543         UVC_COPY_DESCRIPTOR(mem, dst, &uvc_streaming_intf_alt0);
 544
 545         uvc_streaming_header = mem;
 546         UVC_COPY_DESCRIPTORS(mem, dst,
 547                 (const struct usb_descriptor_header**)uvc_streaming_cls);
 548         uvc_streaming_header->wTotalLength = cpu_to_le16(streaming_size);
 549         uvc_streaming_header->bEndpointAddress = uvc->video.ep->address;
 550
 551         UVC_COPY_DESCRIPTORS(mem, dst, uvc_streaming_std);
 552
 553         *dst = NULL;
 554         return hdr;
 555 }
 556
 557 static void
 558 uvc_function_unbind(struct usb_configuration *c, struct usb_function *f)
 559 {
 560         struct usb_composite_dev *cdev = c->cdev;
 561         struct uvc_device *uvc = to_uvc(f);
 562
 563         INFO(cdev, "uvc_function_unbind\n");
 564
 565         video_unregister_device(uvc->vdev);
 566         uvc->control_ep->driver_data = NULL;
 567         uvc->video.ep->driver_data = NULL;
 568
 569         uvc_en_us_strings[UVC_STRING_CONTROL_IDX].id = 0;
 570         usb_ep_free_request(cdev->gadget->ep0, uvc->control_req);
 571         kfree(uvc->control_buf);
 572
 573         usb_free_all_descriptors(f);
 574
 575         kfree(uvc);
 576 }
 577
 578 static int __init
 579 uvc_function_bind(struct usb_configuration *c, struct usb_function *f)
 580 {
 581         struct usb_composite_dev *cdev = c->cdev;
 582         struct uvc_device *uvc = to_uvc(f);
 583         unsigned int max_packet_mult;
 584         unsigned int max_packet_size;
 585         struct usb_ep *ep;
 586         int ret = -EINVAL;
 587
 588         INFO(cdev, "uvc_function_bind\n");
 589
 590         /* Sanity check the streaming endpoint module parameters.
 591          */
 592         streaming_interval = clamp(streaming_interval, 1U, 16U);
 593         streaming_maxpacket = clamp(streaming_maxpacket, 1U, 3072U);
 594         streaming_maxburst = min(streaming_maxburst, 15U);
 595
 596         /* Fill in the FS/HS/SS Video Streaming specific descriptors from the
 597          * module parameters.
 598          *
 599          * NOTE: We assume that the user knows what they are doing and won't
 600          * give parameters that their UDC doesn't support.
 601          */
 602         if (streaming_maxpacket <= 1024) {
 603                 max_packet_mult = 1;
 604                 max_packet_size = streaming_maxpacket;
 605         } else if (streaming_maxpacket <= 2048) {
 606                 max_packet_mult = 2;
 607                 max_packet_size = streaming_maxpacket / 2;
 608         } else {
 609                 max_packet_mult = 3;
 610                 max_packet_size = streaming_maxpacket / 3;
 611         }
 612
 613         uvc_fs_streaming_ep.wMaxPacketSize = min(streaming_maxpacket, 1023U);
 614         uvc_fs_streaming_ep.bInterval = streaming_interval;
 615
 616         uvc_hs_streaming_ep.wMaxPacketSize = max_packet_size;
 617         uvc_hs_streaming_ep.wMaxPacketSize |= ((max_packet_mult - 1) << 11);
 618         uvc_hs_streaming_ep.bInterval = streaming_interval;
 619
 620         uvc_ss_streaming_ep.wMaxPacketSize = max_packet_size;
 621         uvc_ss_streaming_ep.bInterval = streaming_interval;
 622         uvc_ss_streaming_comp.bmAttributes = max_packet_mult - 1;
 623         uvc_ss_streaming_comp.bMaxBurst = streaming_maxburst;
 624         uvc_ss_streaming_comp.wBytesPerInterval =
 625                 max_packet_size * max_packet_mult * streaming_maxburst;
 626
 627         /* Allocate endpoints. */
 628         ep = usb_ep_autoconfig(cdev->gadget, &uvc_control_ep);
 629         if (!ep) {
 630                 INFO(cdev, "Unable to allocate control EP\n");
 631                 goto error;
 632         }
 633         uvc->control_ep = ep;
 634         ep->driver_data = uvc;
 635
 636         if (gadget_is_superspeed(c->cdev->gadget))
 637                 ep = usb_ep_autoconfig_ss(cdev->gadget, &uvc_ss_streaming_ep,
 638                                           &uvc_ss_streaming_comp);
 639         else if (gadget_is_dualspeed(cdev->gadget))
 640                 ep = usb_ep_autoconfig(cdev->gadget, &uvc_hs_streaming_ep);
 641         else
 642                 ep = usb_ep_autoconfig(cdev->gadget, &uvc_fs_streaming_ep);
 643
 644         if (!ep) {
 645                 INFO(cdev, "Unable to allocate streaming EP\n");
 646                 goto error;
 647         }
 648         uvc->video.ep = ep;
 649         ep->driver_data = uvc;
 650
 651         uvc_fs_streaming_ep.bEndpointAddress = uvc->video.ep->address;
 652         uvc_hs_streaming_ep.bEndpointAddress = uvc->video.ep->address;
 653         uvc_ss_streaming_ep.bEndpointAddress = uvc->video.ep->address;
 654
 655         /* Allocate interface IDs. */
 656         if ((ret = usb_interface_id(c, f)) < 0)
 657                 goto error;
 658         uvc_iad.bFirstInterface = ret;
 659         uvc_control_intf.bInterfaceNumber = ret;
 660         uvc->control_intf = ret;
 661
 662         if ((ret = usb_interface_id(c, f)) < 0)
 663                 goto error;
 664         uvc_streaming_intf_alt0.bInterfaceNumber = ret;
 665         uvc_streaming_intf_alt1.bInterfaceNumber = ret;
 666         uvc->streaming_intf = ret;
 667
 668         /* Copy descriptors */
 669         f->fs_descriptors = uvc_copy_descriptors(uvc, USB_SPEED_FULL);
 670         if (gadget_is_dualspeed(cdev->gadget))
 671                 f->hs_descriptors = uvc_copy_descriptors(uvc, USB_SPEED_HIGH);
 672         if (gadget_is_superspeed(c->cdev->gadget))
 673                 f->ss_descriptors = uvc_copy_descriptors(uvc, USB_SPEED_SUPER);
 674
 675         /* Preallocate control endpoint request. */
 676         uvc->control_req = usb_ep_alloc_request(cdev->gadget->ep0, GFP_KERNEL);
 677         uvc->control_buf = kmalloc(UVC_MAX_REQUEST_SIZE, GFP_KERNEL);
 678         if (uvc->control_req == NULL || uvc->control_buf == NULL) {
 679                 ret = -ENOMEM;
 680                 goto error;
 681         }
 682
 683         uvc->control_req->buf = uvc->control_buf;
 684         uvc->control_req->complete = uvc_function_ep0_complete;
 685         uvc->control_req->context = uvc;
 686
 687         /* Avoid letting this gadget enumerate until the userspace server is
 688          * active.
 689          */
 690         if ((ret = usb_function_deactivate(f)) < 0)
 691                 goto error;
 692
 693         /* Initialise video. */
 694         ret = uvc_video_init(&uvc->video);
 695         if (ret < 0)
 696                 goto error;
 697
 698         /* Register a V4L2 device. */
 699         ret = uvc_register_video(uvc);
 700         if (ret < 0) {
 701                 printk(KERN_INFO "Unable to register video device\n");
 702                 goto error;
 703         }
 704
 705         return 0;
 706
 707 error:
 708         if (uvc->vdev)
 709                 video_device_release(uvc->vdev);
 710
 711         if (uvc->control_ep)
 712                 uvc->control_ep->driver_data = NULL;
 713         if (uvc->video.ep)
 714                 uvc->video.ep->driver_data = NULL;
 715
 716         if (uvc->control_req) {
 717                 usb_ep_free_request(cdev->gadget->ep0, uvc->control_req);
 718                 kfree(uvc->control_buf);
 719         }
 720
 721         usb_free_all_descriptors(f);
 722         return ret;
 723 }
 724
 725 /* --------------------------------------------------------------------------
 726  * USB gadget function
 727  */
 728
 729 /**
 730  * uvc_bind_config - add a UVC function to a configuration
 731  * @c: the configuration to support the UVC instance
 732  * Context: single threaded during gadget setup
 733  *
 734  * Returns zero on success, else negative errno.
 735  *
 736  * Caller must have called @uvc_setup(). Caller is also responsible for
 737  * calling @uvc_cleanup() before module unload.
 738  */
 739 int __init
 740 uvc_bind_config(struct usb_configuration *c,
 741                 const struct uvc_descriptor_header * const *fs_control,
 742                 const struct uvc_descriptor_header * const *ss_control,
 743                 const struct uvc_descriptor_header * const *fs_streaming,
 744                 const struct uvc_descriptor_header * const *hs_streaming,
 745                 const struct uvc_descriptor_header * const *ss_streaming)
 746 {
 747         struct uvc_device *uvc;
 748         int ret = 0;
 749
 750         /* TODO Check if the USB device controller supports the required
 751          * features.
 752          */
 753         if (!gadget_is_dualspeed(c->cdev->gadget))
 754                 return -EINVAL;
 755
 756         uvc = kzalloc(sizeof(*uvc), GFP_KERNEL);
 757         if (uvc == NULL)
 758                 return -ENOMEM;
 759
 760         uvc->state = UVC_STATE_DISCONNECTED;
 761
 762         /* Validate the descriptors. */
 763         if (fs_control == NULL || fs_control[0] == NULL ||
 764             fs_control[0]->bDescriptorSubType != UVC_VC_HEADER)
 765                 goto error;
 766
 767         if (ss_control == NULL || ss_control[0] == NULL ||
 768             ss_control[0]->bDescriptorSubType != UVC_VC_HEADER)
 769                 goto error;
 770
 771         if (fs_streaming == NULL || fs_streaming[0] == NULL ||
 772             fs_streaming[0]->bDescriptorSubType != UVC_VS_INPUT_HEADER)
 773                 goto error;
 774
 775         if (hs_streaming == NULL || hs_streaming[0] == NULL ||
 776             hs_streaming[0]->bDescriptorSubType != UVC_VS_INPUT_HEADER)
 777                 goto error;
 778
 779         if (ss_streaming == NULL || ss_streaming[0] == NULL ||
 780             ss_streaming[0]->bDescriptorSubType != UVC_VS_INPUT_HEADER)
 781                 goto error;
 782
 783         uvc->desc.fs_control = fs_control;
 784         uvc->desc.ss_control = ss_control;
 785         uvc->desc.fs_streaming = fs_streaming;
 786         uvc->desc.hs_streaming = hs_streaming;
 787         uvc->desc.ss_streaming = ss_streaming;
 788
 789         /* String descriptors are global, we only need to allocate string IDs
 790          * for the first UVC function. UVC functions beyond the first (if any)
 791          * will reuse the same IDs.
 792          */
 793         if (uvc_en_us_strings[UVC_STRING_CONTROL_IDX].id == 0) {
 794                 ret = usb_string_ids_tab(c->cdev, uvc_en_us_strings);
 795                 if (ret)
 796                         goto error;
 797                 uvc_iad.iFunction =
 798                         uvc_en_us_strings[UVC_STRING_CONTROL_IDX].id;
 799                 uvc_control_intf.iInterface =
 800                         uvc_en_us_strings[UVC_STRING_CONTROL_IDX].id;
 801                 ret = uvc_en_us_strings[UVC_STRING_STREAMING_IDX].id;
 802                 uvc_streaming_intf_alt0.iInterface = ret;
 803                 uvc_streaming_intf_alt1.iInterface = ret;
 804         }
 805
 806         /* Register the function. */
 807         uvc->func.name = "uvc";
 808         uvc->func.strings = uvc_function_strings;
 809         uvc->func.bind = uvc_function_bind;
 810         uvc->func.unbind = uvc_function_unbind;
 811         uvc->func.get_alt = uvc_function_get_alt;
 812         uvc->func.set_alt = uvc_function_set_alt;
 813         uvc->func.disable = uvc_function_disable;
 814         uvc->func.setup = uvc_function_setup;
 815
 816         ret = usb_add_function(c, &uvc->func);
 817         if (ret)
 818                 kfree(uvc);
 819
 820         return ret;
 821
 822 error:
 823         kfree(uvc);
 824         return ret;
 825 }
 826
 827 module_param_named(trace, uvc_gadget_trace_param, uint, S_IRUGO|S_IWUSR);
 828 MODULE_PARM_DESC(trace, "Trace level bitmask");
 829