drivers/usb/gadget/function/f_uvc.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  *      uvc_gadget.c  --  USB Video Class Gadget driver
   4  *
   5  *      Copyright (C) 2009-2010
   6  *          Laurent Pinchart (laurent.pinchart@ideasonboard.com)
   7  */
   8
   9 #include <linux/device.h>
  10 #include <linux/errno.h>
  11 #include <linux/fs.h>
  12 #include <linux/kernel.h>
  13 #include <linux/list.h>
  14 #include <linux/module.h>
  15 #include <linux/mutex.h>
  16 #include <linux/string.h>
  17 #include <linux/usb/ch9.h>
  18 #include <linux/usb/gadget.h>
  19 #include <linux/usb/g_uvc.h>
  20 #include <linux/usb/video.h>
  21 #include <linux/vmalloc.h>
  22 #include <linux/wait.h>
  23
  24 #include <media/v4l2-dev.h>
  25 #include <media/v4l2-event.h>
  26
  27 #include "uvc.h"
  28 #include "uvc_configfs.h"
  29 #include "uvc_v4l2.h"
  30 #include "uvc_video.h"
  31
  32 unsigned int uvc_gadget_trace_param;
  33 module_param_named(trace, uvc_gadget_trace_param, uint, 0644);
  34 MODULE_PARM_DESC(trace, "Trace level bitmask");
  35
  36 /* --------------------------------------------------------------------------
  37  * Function descriptors
  38  */
  39
  40 /* string IDs are assigned dynamically */
  41
  42 static struct usb_string uvc_en_us_strings[] = {
  43         /* [UVC_STRING_CONTROL_IDX].s = DYNAMIC, */
  44         [UVC_STRING_STREAMING_IDX].s = "Video Streaming",
  45         {  }
  46 };
  47
  48 static struct usb_gadget_strings uvc_stringtab = {
  49         .language = 0x0409,     /* en-us */
  50         .strings = uvc_en_us_strings,
  51 };
  52
  53 static struct usb_gadget_strings *uvc_function_strings[] = {
  54         &uvc_stringtab,
  55         NULL,
  56 };
  57
  58 #define UVC_INTF_VIDEO_CONTROL                  0
  59 #define UVC_INTF_VIDEO_STREAMING                1
  60
  61 #define UVC_STATUS_MAX_PACKET_SIZE              16      /* 16 bytes status */
  62
  63 static struct usb_interface_assoc_descriptor uvc_iad = {
  64         .bLength                = sizeof(uvc_iad),
  65         .bDescriptorType        = USB_DT_INTERFACE_ASSOCIATION,
  66         .bFirstInterface        = 0,
  67         .bInterfaceCount        = 2,
  68         .bFunctionClass         = USB_CLASS_VIDEO,
  69         .bFunctionSubClass      = UVC_SC_VIDEO_INTERFACE_COLLECTION,
  70         .bFunctionProtocol      = 0x00,
  71         .iFunction              = 0,
  72 };
  73
  74 static struct usb_interface_descriptor uvc_control_intf = {
  75         .bLength                = USB_DT_INTERFACE_SIZE,
  76         .bDescriptorType        = USB_DT_INTERFACE,
  77         .bInterfaceNumber       = UVC_INTF_VIDEO_CONTROL,
  78         .bAlternateSetting      = 0,
  79         .bNumEndpoints          = 0,
  80         .bInterfaceClass        = USB_CLASS_VIDEO,
  81         .bInterfaceSubClass     = UVC_SC_VIDEOCONTROL,
  82         .bInterfaceProtocol     = 0x00,
  83         .iInterface             = 0,
  84 };
  85
  86 static struct usb_endpoint_descriptor uvc_interrupt_ep = {
  87         .bLength                = USB_DT_ENDPOINT_SIZE,
  88         .bDescriptorType        = USB_DT_ENDPOINT,
  89         .bEndpointAddress       = USB_DIR_IN,
  90         .bmAttributes           = USB_ENDPOINT_XFER_INT,
  91         .wMaxPacketSize         = cpu_to_le16(UVC_STATUS_MAX_PACKET_SIZE),
  92         .bInterval              = 8,
  93 };
  94
  95 static struct usb_ss_ep_comp_descriptor uvc_ss_interrupt_comp = {
  96         .bLength                = sizeof(uvc_ss_interrupt_comp),
  97         .bDescriptorType        = USB_DT_SS_ENDPOINT_COMP,
  98         /* The following 3 values can be tweaked if necessary. */
  99         .bMaxBurst              = 0,
 100         .bmAttributes           = 0,
 101         .wBytesPerInterval      = cpu_to_le16(UVC_STATUS_MAX_PACKET_SIZE),
 102 };
 103
 104 static struct uvc_control_endpoint_descriptor uvc_interrupt_cs_ep = {
 105         .bLength                = UVC_DT_CONTROL_ENDPOINT_SIZE,
 106         .bDescriptorType        = USB_DT_CS_ENDPOINT,
 107         .bDescriptorSubType     = UVC_EP_INTERRUPT,
 108         .wMaxTransferSize       = cpu_to_le16(UVC_STATUS_MAX_PACKET_SIZE),
 109 };
 110
 111 static struct usb_interface_descriptor uvc_streaming_intf_alt0 = {
 112         .bLength                = USB_DT_INTERFACE_SIZE,
 113         .bDescriptorType        = USB_DT_INTERFACE,
 114         .bInterfaceNumber       = UVC_INTF_VIDEO_STREAMING,
 115         .bAlternateSetting      = 0,
 116         .bNumEndpoints          = 0,
 117         .bInterfaceClass        = USB_CLASS_VIDEO,
 118         .bInterfaceSubClass     = UVC_SC_VIDEOSTREAMING,
 119         .bInterfaceProtocol     = 0x00,
 120         .iInterface             = 0,
 121 };
 122
 123 static struct usb_interface_descriptor uvc_streaming_intf_alt1 = {
 124         .bLength                = USB_DT_INTERFACE_SIZE,
 125         .bDescriptorType        = USB_DT_INTERFACE,
 126         .bInterfaceNumber       = UVC_INTF_VIDEO_STREAMING,
 127         .bAlternateSetting      = 1,
 128         .bNumEndpoints          = 1,
 129         .bInterfaceClass        = USB_CLASS_VIDEO,
 130         .bInterfaceSubClass     = UVC_SC_VIDEOSTREAMING,
 131         .bInterfaceProtocol     = 0x00,
 132         .iInterface             = 0,
 133 };
 134
 135 static struct usb_endpoint_descriptor uvc_fs_streaming_ep = {
 136         .bLength                = USB_DT_ENDPOINT_SIZE,
 137         .bDescriptorType        = USB_DT_ENDPOINT,
 138         .bEndpointAddress       = USB_DIR_IN,
 139         .bmAttributes           = USB_ENDPOINT_SYNC_ASYNC
 140                                 | USB_ENDPOINT_XFER_ISOC,
 141         /*
 142          * The wMaxPacketSize and bInterval values will be initialized from
 143          * module parameters.
 144          */
 145 };
 146
 147 static struct usb_endpoint_descriptor uvc_hs_streaming_ep = {
 148         .bLength                = USB_DT_ENDPOINT_SIZE,
 149         .bDescriptorType        = USB_DT_ENDPOINT,
 150         .bEndpointAddress       = USB_DIR_IN,
 151         .bmAttributes           = USB_ENDPOINT_SYNC_ASYNC
 152                                 | USB_ENDPOINT_XFER_ISOC,
 153         /*
 154          * The wMaxPacketSize and bInterval values will be initialized from
 155          * module parameters.
 156          */
 157 };
 158
 159 static struct usb_endpoint_descriptor uvc_ss_streaming_ep = {
 160         .bLength                = USB_DT_ENDPOINT_SIZE,
 161         .bDescriptorType        = USB_DT_ENDPOINT,
 162
 163         .bEndpointAddress       = USB_DIR_IN,
 164         .bmAttributes           = USB_ENDPOINT_SYNC_ASYNC
 165                                 | USB_ENDPOINT_XFER_ISOC,
 166         /*
 167          * The wMaxPacketSize and bInterval values will be initialized from
 168          * module parameters.
 169          */
 170 };
 171
 172 static struct usb_ss_ep_comp_descriptor uvc_ss_streaming_comp = {
 173         .bLength                = sizeof(uvc_ss_streaming_comp),
 174         .bDescriptorType        = USB_DT_SS_ENDPOINT_COMP,
 175         /*
 176          * The bMaxBurst, bmAttributes and wBytesPerInterval values will be
 177          * initialized from module parameters.
 178          */
 179 };
 180
 181 static const struct usb_descriptor_header * const uvc_fs_streaming[] = {
 182         (struct usb_descriptor_header *) &uvc_streaming_intf_alt1,
 183         (struct usb_descriptor_header *) &uvc_fs_streaming_ep,
 184         NULL,
 185 };
 186
 187 static const struct usb_descriptor_header * const uvc_hs_streaming[] = {
 188         (struct usb_descriptor_header *) &uvc_streaming_intf_alt1,
 189         (struct usb_descriptor_header *) &uvc_hs_streaming_ep,
 190         NULL,
 191 };
 192
 193 static const struct usb_descriptor_header * const uvc_ss_streaming[] = {
 194         (struct usb_descriptor_header *) &uvc_streaming_intf_alt1,
 195         (struct usb_descriptor_header *) &uvc_ss_streaming_ep,
 196         (struct usb_descriptor_header *) &uvc_ss_streaming_comp,
 197         NULL,
 198 };
 199
 200 /* --------------------------------------------------------------------------
 201  * Control requests
 202  */
 203
 204 static void
 205 uvc_function_ep0_complete(struct usb_ep *ep, struct usb_request *req)
 206 {
 207         struct uvc_device *uvc = req->context;
 208         struct v4l2_event v4l2_event;
 209         struct uvc_event *uvc_event = (void *)&v4l2_event.u.data;
 210
 211         if (uvc->event_setup_out) {
 212                 uvc->event_setup_out = 0;
 213
 214                 memset(&v4l2_event, 0, sizeof(v4l2_event));
 215                 v4l2_event.type = UVC_EVENT_DATA;
 216                 uvc_event->data.length = min_t(unsigned int, req->actual,
 217                         sizeof(uvc_event->data.data));
 218                 memcpy(&uvc_event->data.data, req->buf, uvc_event->data.length);
 219                 v4l2_event_queue(&uvc->vdev, &v4l2_event);
 220         }
 221 }
 222
 223 static int
 224 uvc_function_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
 225 {
 226         struct uvc_device *uvc = to_uvc(f);
 227         struct v4l2_event v4l2_event;
 228         struct uvc_event *uvc_event = (void *)&v4l2_event.u.data;
 229         unsigned int interface = le16_to_cpu(ctrl->wIndex) & 0xff;
 230         struct usb_ctrlrequest *mctrl;
 231
 232         if ((ctrl->bRequestType & USB_TYPE_MASK) != USB_TYPE_CLASS) {
 233                 uvcg_info(f, "invalid request type\n");
 234                 return -EINVAL;
 235         }
 236
 237         /* Stall too big requests. */
 238         if (le16_to_cpu(ctrl->wLength) > UVC_MAX_REQUEST_SIZE)
 239                 return -EINVAL;
 240
 241         /*
 242          * Tell the complete callback to generate an event for the next request
 243          * that will be enqueued by UVCIOC_SEND_RESPONSE.
 244          */
 245         uvc->event_setup_out = !(ctrl->bRequestType & USB_DIR_IN);
 246         uvc->event_length = le16_to_cpu(ctrl->wLength);
 247
 248         memset(&v4l2_event, 0, sizeof(v4l2_event));
 249         v4l2_event.type = UVC_EVENT_SETUP;
 250         memcpy(&uvc_event->req, ctrl, sizeof(uvc_event->req));
 251
 252         /* check for the interface number, fixup the interface number in
 253          * the ctrl request so the userspace doesn't have to bother with
 254          * offset and configfs parsing
 255          */
 256         mctrl = &uvc_event->req;
 257         mctrl->wIndex &= ~cpu_to_le16(0xff);
 258         if (interface == uvc->streaming_intf)
 259                 mctrl->wIndex = cpu_to_le16(UVC_STRING_STREAMING_IDX);
 260
 261         v4l2_event_queue(&uvc->vdev, &v4l2_event);
 262
 263         return 0;
 264 }
 265
 266 void uvc_function_setup_continue(struct uvc_device *uvc, int disable_ep)
 267 {
 268         struct usb_composite_dev *cdev = uvc->func.config->cdev;
 269
 270         if (disable_ep && uvc->video.ep)
 271                 usb_ep_disable(uvc->video.ep);
 272
 273         usb_composite_setup_continue(cdev);
 274 }
 275
 276 static int
 277 uvc_function_get_alt(struct usb_function *f, unsigned interface)
 278 {
 279         struct uvc_device *uvc = to_uvc(f);
 280
 281         uvcg_info(f, "%s(%u)\n", __func__, interface);
 282
 283         if (interface == uvc->control_intf)
 284                 return 0;
 285         else if (interface != uvc->streaming_intf)
 286                 return -EINVAL;
 287         else
 288                 return uvc->video.ep->enabled ? 1 : 0;
 289 }
 290
 291 static int
 292 uvc_function_set_alt(struct usb_function *f, unsigned interface, unsigned alt)
 293 {
 294         struct uvc_device *uvc = to_uvc(f);
 295         struct usb_composite_dev *cdev = f->config->cdev;
 296         struct v4l2_event v4l2_event;
 297         struct uvc_event *uvc_event = (void *)&v4l2_event.u.data;
 298         int ret;
 299
 300         uvcg_info(f, "%s(%u, %u)\n", __func__, interface, alt);
 301
 302         if (interface == uvc->control_intf) {
 303                 if (alt)
 304                         return -EINVAL;
 305
 306                 if (uvc->enable_interrupt_ep) {
 307                         uvcg_info(f, "reset UVC interrupt endpoint\n");
 308                         usb_ep_disable(uvc->interrupt_ep);
 309
 310                         if (!uvc->interrupt_ep->desc)
 311                                 if (config_ep_by_speed(cdev->gadget, f,
 312                                                        uvc->interrupt_ep))
 313                                         return -EINVAL;
 314
 315                         usb_ep_enable(uvc->interrupt_ep);
 316                 }
 317
 318                 if (uvc->state == UVC_STATE_DISCONNECTED) {
 319                         memset(&v4l2_event, 0, sizeof(v4l2_event));
 320                         v4l2_event.type = UVC_EVENT_CONNECT;
 321                         uvc_event->speed = cdev->gadget->speed;
 322                         v4l2_event_queue(&uvc->vdev, &v4l2_event);
 323
 324                         uvc->state = UVC_STATE_CONNECTED;
 325                 }
 326
 327                 return 0;
 328         }
 329
 330         if (interface != uvc->streaming_intf)
 331                 return -EINVAL;
 332
 333         /* TODO
 334         if (usb_endpoint_xfer_bulk(&uvc->desc.vs_ep))
 335                 return alt ? -EINVAL : 0;
 336         */
 337
 338         switch (alt) {
 339         case 0:
 340                 if (uvc->state != UVC_STATE_STREAMING)
 341                         return 0;
 342
 343                 memset(&v4l2_event, 0, sizeof(v4l2_event));
 344                 v4l2_event.type = UVC_EVENT_STREAMOFF;
 345                 v4l2_event_queue(&uvc->vdev, &v4l2_event);
 346
 347                 return USB_GADGET_DELAYED_STATUS;
 348
 349         case 1:
 350                 if (uvc->state != UVC_STATE_CONNECTED)
 351                         return 0;
 352
 353                 if (!uvc->video.ep)
 354                         return -EINVAL;
 355
 356                 uvcg_info(f, "reset UVC\n");
 357                 usb_ep_disable(uvc->video.ep);
 358
 359                 ret = config_ep_by_speed(f->config->cdev->gadget,
 360                                 &(uvc->func), uvc->video.ep);
 361                 if (ret)
 362                         return ret;
 363                 usb_ep_enable(uvc->video.ep);
 364
 365                 memset(&v4l2_event, 0, sizeof(v4l2_event));
 366                 v4l2_event.type = UVC_EVENT_STREAMON;
 367                 v4l2_event_queue(&uvc->vdev, &v4l2_event);
 368                 return USB_GADGET_DELAYED_STATUS;
 369
 370         default:
 371                 return -EINVAL;
 372         }
 373 }
 374
 375 static void
 376 uvc_function_disable(struct usb_function *f)
 377 {
 378         struct uvc_device *uvc = to_uvc(f);
 379         struct v4l2_event v4l2_event;
 380
 381         uvcg_info(f, "%s()\n", __func__);
 382
 383         memset(&v4l2_event, 0, sizeof(v4l2_event));
 384         v4l2_event.type = UVC_EVENT_DISCONNECT;
 385         v4l2_event_queue(&uvc->vdev, &v4l2_event);
 386
 387         uvc->state = UVC_STATE_DISCONNECTED;
 388
 389         usb_ep_disable(uvc->video.ep);
 390         if (uvc->enable_interrupt_ep)
 391                 usb_ep_disable(uvc->interrupt_ep);
 392 }
 393
 394 /* --------------------------------------------------------------------------
 395  * Connection / disconnection
 396  */
 397
 398 void
 399 uvc_function_connect(struct uvc_device *uvc)
 400 {
 401         int ret;
 402
 403         if ((ret = usb_function_activate(&uvc->func)) < 0)
 404                 uvcg_info(&uvc->func, "UVC connect failed with %d\n", ret);
 405 }
 406
 407 void
 408 uvc_function_disconnect(struct uvc_device *uvc)
 409 {
 410         int ret;
 411
 412         if ((ret = usb_function_deactivate(&uvc->func)) < 0)
 413                 uvcg_info(&uvc->func, "UVC disconnect failed with %d\n", ret);
 414 }
 415
 416 /* --------------------------------------------------------------------------
 417  * USB probe and disconnect
 418  */
 419
 420 static ssize_t function_name_show(struct device *dev,
 421                                   struct device_attribute *attr, char *buf)
 422 {
 423         struct uvc_device *uvc = dev_get_drvdata(dev);
 424
 425         return sprintf(buf, "%s\n", uvc->func.fi->group.cg_item.ci_name);
 426 }
 427
 428 static DEVICE_ATTR_RO(function_name);
 429
 430 static int
 431 uvc_register_video(struct uvc_device *uvc)
 432 {
 433         struct usb_composite_dev *cdev = uvc->func.config->cdev;
 434         int ret;
 435
 436         /* TODO reference counting. */
 437         memset(&uvc->vdev, 0, sizeof(uvc->vdev));
 438         uvc->vdev.v4l2_dev = &uvc->v4l2_dev;
 439         uvc->vdev.v4l2_dev->dev = &cdev->gadget->dev;
 440         uvc->vdev.fops = &uvc_v4l2_fops;
 441         uvc->vdev.ioctl_ops = &uvc_v4l2_ioctl_ops;
 442         uvc->vdev.release = video_device_release_empty;
 443         uvc->vdev.vfl_dir = VFL_DIR_TX;
 444         uvc->vdev.lock = &uvc->video.mutex;
 445         uvc->vdev.device_caps = V4L2_CAP_VIDEO_OUTPUT | V4L2_CAP_STREAMING;
 446         strscpy(uvc->vdev.name, cdev->gadget->name, sizeof(uvc->vdev.name));
 447
 448         video_set_drvdata(&uvc->vdev, uvc);
 449
 450         ret = video_register_device(&uvc->vdev, VFL_TYPE_VIDEO, -1);
 451         if (ret < 0)
 452                 return ret;
 453
 454         ret = device_create_file(&uvc->vdev.dev, &dev_attr_function_name);
 455         if (ret < 0) {
 456                 video_unregister_device(&uvc->vdev);
 457                 return ret;
 458         }
 459
 460         return 0;
 461 }
 462
 463 #define UVC_COPY_DESCRIPTOR(mem, dst, desc) \
 464         do { \
 465                 memcpy(mem, desc, (desc)->bLength); \
 466                 *(dst)++ = mem; \
 467                 mem += (desc)->bLength; \
 468         } while (0);
 469
 470 #define UVC_COPY_DESCRIPTORS(mem, dst, src) \
 471         do { \
 472                 const struct usb_descriptor_header * const *__src; \
 473                 for (__src = src; *__src; ++__src) { \
 474                         memcpy(mem, *__src, (*__src)->bLength); \
 475                         *dst++ = mem; \
 476                         mem += (*__src)->bLength; \
 477                 } \
 478         } while (0)
 479
 480 #define UVC_COPY_XU_DESCRIPTOR(mem, dst, desc)                                  \
 481         do {                                                                    \
 482                 *(dst)++ = mem;                                                 \
 483                 memcpy(mem, desc, 22); /* bLength to bNrInPins */               \
 484                 mem += 22;                                                      \
 485                                                                                 \
 486                 memcpy(mem, (desc)->baSourceID, (desc)->bNrInPins);             \
 487                 mem += (desc)->bNrInPins;                                       \
 488                                                                                 \
 489                 memcpy(mem, &(desc)->bControlSize, 1);                          \
 490                 mem++;                                                          \
 491                                                                                 \
 492                 memcpy(mem, (desc)->bmControls, (desc)->bControlSize);          \
 493                 mem += (desc)->bControlSize;                                    \
 494                                                                                 \
 495                 memcpy(mem, &(desc)->iExtension, 1);                            \
 496                 mem++;                                                          \
 497         } while (0)
 498
 499 static struct usb_descriptor_header **
 500 uvc_copy_descriptors(struct uvc_device *uvc, enum usb_device_speed speed)
 501 {
 502         struct uvc_input_header_descriptor *uvc_streaming_header;
 503         struct uvc_header_descriptor *uvc_control_header;
 504         const struct uvc_descriptor_header * const *uvc_control_desc;
 505         const struct uvc_descriptor_header * const *uvc_streaming_cls;
 506         const struct usb_descriptor_header * const *uvc_streaming_std;
 507         const struct usb_descriptor_header * const *src;
 508         struct usb_descriptor_header **dst;
 509         struct usb_descriptor_header **hdr;
 510         struct uvcg_extension *xu;
 511         unsigned int control_size;
 512         unsigned int streaming_size;
 513         unsigned int n_desc;
 514         unsigned int bytes;
 515         void *mem;
 516
 517         switch (speed) {
 518         case USB_SPEED_SUPER_PLUS:
 519         case USB_SPEED_SUPER:
 520                 uvc_control_desc = uvc->desc.ss_control;
 521                 uvc_streaming_cls = uvc->desc.ss_streaming;
 522                 uvc_streaming_std = uvc_ss_streaming;
 523                 break;
 524
 525         case USB_SPEED_HIGH:
 526                 uvc_control_desc = uvc->desc.fs_control;
 527                 uvc_streaming_cls = uvc->desc.hs_streaming;
 528                 uvc_streaming_std = uvc_hs_streaming;
 529                 break;
 530
 531         case USB_SPEED_FULL:
 532         default:
 533                 uvc_control_desc = uvc->desc.fs_control;
 534                 uvc_streaming_cls = uvc->desc.fs_streaming;
 535                 uvc_streaming_std = uvc_fs_streaming;
 536                 break;
 537         }
 538
 539         if (!uvc_control_desc || !uvc_streaming_cls)
 540                 return ERR_PTR(-ENODEV);
 541
 542         /*
 543          * Descriptors layout
 544          *
 545          * uvc_iad
 546          * uvc_control_intf
 547          * Class-specific UVC control descriptors
 548          * uvc_interrupt_ep
 549          * uvc_interrupt_cs_ep
 550          * uvc_ss_interrupt_comp (for SS only)
 551          * uvc_streaming_intf_alt0
 552          * Class-specific UVC streaming descriptors
 553          * uvc_{fs|hs}_streaming
 554          */
 555
 556         /* Count descriptors and compute their size. */
 557         control_size = 0;
 558         streaming_size = 0;
 559         bytes = uvc_iad.bLength + uvc_control_intf.bLength
 560               + uvc_streaming_intf_alt0.bLength;
 561
 562         n_desc = 3;
 563         if (uvc->enable_interrupt_ep) {
 564                 bytes += uvc_interrupt_ep.bLength + uvc_interrupt_cs_ep.bLength;
 565                 n_desc += 2;
 566
 567                 if (speed == USB_SPEED_SUPER ||
 568                     speed == USB_SPEED_SUPER_PLUS) {
 569                         bytes += uvc_ss_interrupt_comp.bLength;
 570                         n_desc += 1;
 571                 }
 572         }
 573
 574         for (src = (const struct usb_descriptor_header **)uvc_control_desc;
 575              *src; ++src) {
 576                 control_size += (*src)->bLength;
 577                 bytes += (*src)->bLength;
 578                 n_desc++;
 579         }
 580
 581         list_for_each_entry(xu, uvc->desc.extension_units, list) {
 582                 control_size += xu->desc.bLength;
 583                 bytes += xu->desc.bLength;
 584                 n_desc++;
 585         }
 586
 587         for (src = (const struct usb_descriptor_header **)uvc_streaming_cls;
 588              *src; ++src) {
 589                 streaming_size += (*src)->bLength;
 590                 bytes += (*src)->bLength;
 591                 n_desc++;
 592         }
 593         for (src = uvc_streaming_std; *src; ++src) {
 594                 bytes += (*src)->bLength;
 595                 n_desc++;
 596         }
 597
 598         mem = kmalloc((n_desc + 1) * sizeof(*src) + bytes, GFP_KERNEL);
 599         if (mem == NULL)
 600                 return NULL;
 601
 602         hdr = mem;
 603         dst = mem;
 604         mem += (n_desc + 1) * sizeof(*src);
 605
 606         /* Copy the descriptors. */
 607         UVC_COPY_DESCRIPTOR(mem, dst, &uvc_iad);
 608         UVC_COPY_DESCRIPTOR(mem, dst, &uvc_control_intf);
 609
 610         uvc_control_header = mem;
 611         UVC_COPY_DESCRIPTORS(mem, dst,
 612                 (const struct usb_descriptor_header **)uvc_control_desc);
 613
 614         list_for_each_entry(xu, uvc->desc.extension_units, list)
 615                 UVC_COPY_XU_DESCRIPTOR(mem, dst, &xu->desc);
 616
 617         uvc_control_header->wTotalLength = cpu_to_le16(control_size);
 618         uvc_control_header->bInCollection = 1;
 619         uvc_control_header->baInterfaceNr[0] = uvc->streaming_intf;
 620
 621         if (uvc->enable_interrupt_ep) {
 622                 UVC_COPY_DESCRIPTOR(mem, dst, &uvc_interrupt_ep);
 623                 if (speed == USB_SPEED_SUPER ||
 624                     speed == USB_SPEED_SUPER_PLUS)
 625                         UVC_COPY_DESCRIPTOR(mem, dst, &uvc_ss_interrupt_comp);
 626
 627                 UVC_COPY_DESCRIPTOR(mem, dst, &uvc_interrupt_cs_ep);
 628         }
 629
 630         UVC_COPY_DESCRIPTOR(mem, dst, &uvc_streaming_intf_alt0);
 631
 632         uvc_streaming_header = mem;
 633         UVC_COPY_DESCRIPTORS(mem, dst,
 634                 (const struct usb_descriptor_header**)uvc_streaming_cls);
 635         uvc_streaming_header->wTotalLength = cpu_to_le16(streaming_size);
 636         uvc_streaming_header->bEndpointAddress = uvc->video.ep->address;
 637
 638         UVC_COPY_DESCRIPTORS(mem, dst, uvc_streaming_std);
 639
 640         *dst = NULL;
 641         return hdr;
 642 }
 643
 644 static int
 645 uvc_function_bind(struct usb_configuration *c, struct usb_function *f)
 646 {
 647         struct usb_composite_dev *cdev = c->cdev;
 648         struct uvc_device *uvc = to_uvc(f);
 649         struct uvcg_extension *xu;
 650         struct usb_string *us;
 651         unsigned int max_packet_mult;
 652         unsigned int max_packet_size;
 653         struct usb_ep *ep;
 654         struct f_uvc_opts *opts;
 655         int ret = -EINVAL;
 656
 657         uvcg_info(f, "%s()\n", __func__);
 658
 659         opts = fi_to_f_uvc_opts(f->fi);
 660         /* Sanity check the streaming endpoint module parameters. */
 661         opts->streaming_interval = clamp(opts->streaming_interval, 1U, 16U);
 662         opts->streaming_maxpacket = clamp(opts->streaming_maxpacket, 1U, 3072U);
 663         opts->streaming_maxburst = min(opts->streaming_maxburst, 15U);
 664
 665         /* For SS, wMaxPacketSize has to be 1024 if bMaxBurst is not 0 */
 666         if (opts->streaming_maxburst &&
 667             (opts->streaming_maxpacket % 1024) != 0) {
 668                 opts->streaming_maxpacket = roundup(opts->streaming_maxpacket, 1024);
 669                 uvcg_info(f, "overriding streaming_maxpacket to %d\n",
 670                           opts->streaming_maxpacket);
 671         }
 672
 673         /*
 674          * Fill in the FS/HS/SS Video Streaming specific descriptors from the
 675          * module parameters.
 676          *
 677          * NOTE: We assume that the user knows what they are doing and won't
 678          * give parameters that their UDC doesn't support.
 679          */
 680         if (opts->streaming_maxpacket <= 1024) {
 681                 max_packet_mult = 1;
 682                 max_packet_size = opts->streaming_maxpacket;
 683         } else if (opts->streaming_maxpacket <= 2048) {
 684                 max_packet_mult = 2;
 685                 max_packet_size = opts->streaming_maxpacket / 2;
 686         } else {
 687                 max_packet_mult = 3;
 688                 max_packet_size = opts->streaming_maxpacket / 3;
 689         }
 690
 691         uvc_fs_streaming_ep.wMaxPacketSize =
 692                 cpu_to_le16(min(opts->streaming_maxpacket, 1023U));
 693         uvc_fs_streaming_ep.bInterval = opts->streaming_interval;
 694
 695         uvc_hs_streaming_ep.wMaxPacketSize =
 696                 cpu_to_le16(max_packet_size | ((max_packet_mult - 1) << 11));
 697
 698         /* A high-bandwidth endpoint must specify a bInterval value of 1 */
 699         if (max_packet_mult > 1)
 700                 uvc_hs_streaming_ep.bInterval = 1;
 701         else
 702                 uvc_hs_streaming_ep.bInterval = opts->streaming_interval;
 703
 704         uvc_ss_streaming_ep.wMaxPacketSize = cpu_to_le16(max_packet_size);
 705         uvc_ss_streaming_ep.bInterval = opts->streaming_interval;
 706         uvc_ss_streaming_comp.bmAttributes = max_packet_mult - 1;
 707         uvc_ss_streaming_comp.bMaxBurst = opts->streaming_maxburst;
 708         uvc_ss_streaming_comp.wBytesPerInterval =
 709                 cpu_to_le16(max_packet_size * max_packet_mult *
 710                             (opts->streaming_maxburst + 1));
 711
 712         /* Allocate endpoints. */
 713         if (opts->enable_interrupt_ep) {
 714                 ep = usb_ep_autoconfig(cdev->gadget, &uvc_interrupt_ep);
 715                 if (!ep) {
 716                         uvcg_info(f, "Unable to allocate interrupt EP\n");
 717                         goto error;
 718                 }
 719                 uvc->interrupt_ep = ep;
 720                 uvc_control_intf.bNumEndpoints = 1;
 721         }
 722         uvc->enable_interrupt_ep = opts->enable_interrupt_ep;
 723
 724         /*
 725          * gadget_is_{super|dual}speed() API check UDC controller capitblity. It should pass down
 726          * highest speed endpoint descriptor to UDC controller. So UDC controller driver can reserve
 727          * enough resource at check_config(), especially mult and maxburst. So UDC driver (such as
 728          * cdns3) can know need at least (mult + 1) * (maxburst + 1) * wMaxPacketSize internal
 729          * memory for this uvc functions. This is the only straightforward method to resolve the UDC
 730          * resource allocation issue in the current gadget framework.
 731          */
 732         if (gadget_is_superspeed(c->cdev->gadget))
 733                 ep = usb_ep_autoconfig_ss(cdev->gadget, &uvc_ss_streaming_ep,
 734                                           &uvc_ss_streaming_comp);
 735         else if (gadget_is_dualspeed(cdev->gadget))
 736                 ep = usb_ep_autoconfig(cdev->gadget, &uvc_hs_streaming_ep);
 737         else
 738                 ep = usb_ep_autoconfig(cdev->gadget, &uvc_fs_streaming_ep);
 739
 740         if (!ep) {
 741                 uvcg_info(f, "Unable to allocate streaming EP\n");
 742                 goto error;
 743         }
 744         uvc->video.ep = ep;
 745
 746         uvc_fs_streaming_ep.bEndpointAddress = uvc->video.ep->address;
 747         uvc_hs_streaming_ep.bEndpointAddress = uvc->video.ep->address;
 748         uvc_ss_streaming_ep.bEndpointAddress = uvc->video.ep->address;
 749
 750         /*
 751          * XUs can have an arbitrary string descriptor describing them. If they
 752          * have one pick up the ID.
 753          */
 754         list_for_each_entry(xu, &opts->extension_units, list)
 755                 if (xu->string_descriptor_index)
 756                         xu->desc.iExtension = cdev->usb_strings[xu->string_descriptor_index].id;
 757
 758         /*
 759          * We attach the hard-coded defaults incase the user does not provide
 760          * any more appropriate strings through configfs.
 761          */
 762         uvc_en_us_strings[UVC_STRING_CONTROL_IDX].s = opts->function_name;
 763         us = usb_gstrings_attach(cdev, uvc_function_strings,
 764                                  ARRAY_SIZE(uvc_en_us_strings));
 765         if (IS_ERR(us)) {
 766                 ret = PTR_ERR(us);
 767                 goto error;
 768         }
 769
 770         uvc_iad.iFunction = opts->iad_index ? cdev->usb_strings[opts->iad_index].id :
 771                             us[UVC_STRING_CONTROL_IDX].id;
 772         uvc_streaming_intf_alt0.iInterface = opts->vs0_index ?
 773                                              cdev->usb_strings[opts->vs0_index].id :
 774                                              us[UVC_STRING_STREAMING_IDX].id;
 775         uvc_streaming_intf_alt1.iInterface = opts->vs1_index ?
 776                                              cdev->usb_strings[opts->vs1_index].id :
 777                                              us[UVC_STRING_STREAMING_IDX].id;
 778
 779         /* Allocate interface IDs. */
 780         if ((ret = usb_interface_id(c, f)) < 0)
 781                 goto error;
 782         uvc_iad.bFirstInterface = ret;
 783         uvc_control_intf.bInterfaceNumber = ret;
 784         uvc->control_intf = ret;
 785         opts->control_interface = ret;
 786
 787         if ((ret = usb_interface_id(c, f)) < 0)
 788                 goto error;
 789         uvc_streaming_intf_alt0.bInterfaceNumber = ret;
 790         uvc_streaming_intf_alt1.bInterfaceNumber = ret;
 791         uvc->streaming_intf = ret;
 792         opts->streaming_interface = ret;
 793
 794         /* Copy descriptors */
 795         f->fs_descriptors = uvc_copy_descriptors(uvc, USB_SPEED_FULL);
 796         if (IS_ERR(f->fs_descriptors)) {
 797                 ret = PTR_ERR(f->fs_descriptors);
 798                 f->fs_descriptors = NULL;
 799                 goto error;
 800         }
 801
 802         f->hs_descriptors = uvc_copy_descriptors(uvc, USB_SPEED_HIGH);
 803         if (IS_ERR(f->hs_descriptors)) {
 804                 ret = PTR_ERR(f->hs_descriptors);
 805                 f->hs_descriptors = NULL;
 806                 goto error;
 807         }
 808
 809         f->ss_descriptors = uvc_copy_descriptors(uvc, USB_SPEED_SUPER);
 810         if (IS_ERR(f->ss_descriptors)) {
 811                 ret = PTR_ERR(f->ss_descriptors);
 812                 f->ss_descriptors = NULL;
 813                 goto error;
 814         }
 815
 816         f->ssp_descriptors = uvc_copy_descriptors(uvc, USB_SPEED_SUPER_PLUS);
 817         if (IS_ERR(f->ssp_descriptors)) {
 818                 ret = PTR_ERR(f->ssp_descriptors);
 819                 f->ssp_descriptors = NULL;
 820                 goto error;
 821         }
 822
 823         /* Preallocate control endpoint request. */
 824         uvc->control_req = usb_ep_alloc_request(cdev->gadget->ep0, GFP_KERNEL);
 825         uvc->control_buf = kmalloc(UVC_MAX_REQUEST_SIZE, GFP_KERNEL);
 826         if (uvc->control_req == NULL || uvc->control_buf == NULL) {
 827                 ret = -ENOMEM;
 828                 goto error;
 829         }
 830
 831         uvc->control_req->buf = uvc->control_buf;
 832         uvc->control_req->complete = uvc_function_ep0_complete;
 833         uvc->control_req->context = uvc;
 834
 835         if (v4l2_device_register(&cdev->gadget->dev, &uvc->v4l2_dev)) {
 836                 uvcg_err(f, "failed to register V4L2 device\n");
 837                 goto error;
 838         }
 839
 840         /* Initialise video. */
 841         ret = uvcg_video_init(&uvc->video, uvc);
 842         if (ret < 0)
 843                 goto v4l2_error;
 844
 845         /* Register a V4L2 device. */
 846         ret = uvc_register_video(uvc);
 847         if (ret < 0) {
 848                 uvcg_err(f, "failed to register video device\n");
 849                 goto v4l2_error;
 850         }
 851
 852         return 0;
 853
 854 v4l2_error:
 855         v4l2_device_unregister(&uvc->v4l2_dev);
 856 error:
 857         if (uvc->control_req)
 858                 usb_ep_free_request(cdev->gadget->ep0, uvc->control_req);
 859         kfree(uvc->control_buf);
 860
 861         usb_free_all_descriptors(f);
 862         return ret;
 863 }
 864
 865 /* --------------------------------------------------------------------------
 866  * USB gadget function
 867  */
 868
 869 static void uvc_free_inst(struct usb_function_instance *f)
 870 {
 871         struct f_uvc_opts *opts = fi_to_f_uvc_opts(f);
 872
 873         mutex_destroy(&opts->lock);
 874         kfree(opts);
 875 }
 876
 877 static struct usb_function_instance *uvc_alloc_inst(void)
 878 {
 879         struct f_uvc_opts *opts;
 880         struct uvc_camera_terminal_descriptor *cd;
 881         struct uvc_processing_unit_descriptor *pd;
 882         struct uvc_output_terminal_descriptor *od;
 883         struct uvc_descriptor_header **ctl_cls;
 884         int ret;
 885
 886         opts = kzalloc(sizeof(*opts), GFP_KERNEL);
 887         if (!opts)
 888                 return ERR_PTR(-ENOMEM);
 889         opts->func_inst.free_func_inst = uvc_free_inst;
 890         mutex_init(&opts->lock);
 891
 892         cd = &opts->uvc_camera_terminal;
 893         cd->bLength                     = UVC_DT_CAMERA_TERMINAL_SIZE(3);
 894         cd->bDescriptorType             = USB_DT_CS_INTERFACE;
 895         cd->bDescriptorSubType          = UVC_VC_INPUT_TERMINAL;
 896         cd->bTerminalID                 = 1;
 897         cd->wTerminalType               = cpu_to_le16(0x0201);
 898         cd->bAssocTerminal              = 0;
 899         cd->iTerminal                   = 0;
 900         cd->wObjectiveFocalLengthMin    = cpu_to_le16(0);
 901         cd->wObjectiveFocalLengthMax    = cpu_to_le16(0);
 902         cd->wOcularFocalLength          = cpu_to_le16(0);
 903         cd->bControlSize                = 3;
 904         cd->bmControls[0]               = 2;
 905         cd->bmControls[1]               = 0;
 906         cd->bmControls[2]               = 0;
 907
 908         pd = &opts->uvc_processing;
 909         pd->bLength                     = UVC_DT_PROCESSING_UNIT_SIZE(2);
 910         pd->bDescriptorType             = USB_DT_CS_INTERFACE;
 911         pd->bDescriptorSubType          = UVC_VC_PROCESSING_UNIT;
 912         pd->bUnitID                     = 2;
 913         pd->bSourceID                   = 1;
 914         pd->wMaxMultiplier              = cpu_to_le16(16*1024);
 915         pd->bControlSize                = 2;
 916         pd->bmControls[0]               = 1;
 917         pd->bmControls[1]               = 0;
 918         pd->iProcessing                 = 0;
 919         pd->bmVideoStandards            = 0;
 920
 921         od = &opts->uvc_output_terminal;
 922         od->bLength                     = UVC_DT_OUTPUT_TERMINAL_SIZE;
 923         od->bDescriptorType             = USB_DT_CS_INTERFACE;
 924         od->bDescriptorSubType          = UVC_VC_OUTPUT_TERMINAL;
 925         od->bTerminalID                 = 3;
 926         od->wTerminalType               = cpu_to_le16(0x0101);
 927         od->bAssocTerminal              = 0;
 928         od->bSourceID                   = 2;
 929         od->iTerminal                   = 0;
 930
 931         /*
 932          * With the ability to add XUs to the UVC function graph, we need to be
 933          * able to allocate unique unit IDs to them. The IDs are 1-based, with
 934          * the CT, PU and OT above consuming the first 3.
 935          */
 936         opts->last_unit_id              = 3;
 937
 938         /* Prepare fs control class descriptors for configfs-based gadgets */
 939         ctl_cls = opts->uvc_fs_control_cls;
 940         ctl_cls[0] = NULL;      /* assigned elsewhere by configfs */
 941         ctl_cls[1] = (struct uvc_descriptor_header *)cd;
 942         ctl_cls[2] = (struct uvc_descriptor_header *)pd;
 943         ctl_cls[3] = (struct uvc_descriptor_header *)od;
 944         ctl_cls[4] = NULL;      /* NULL-terminate */
 945         opts->fs_control =
 946                 (const struct uvc_descriptor_header * const *)ctl_cls;
 947
 948         /* Prepare hs control class descriptors for configfs-based gadgets */
 949         ctl_cls = opts->uvc_ss_control_cls;
 950         ctl_cls[0] = NULL;      /* assigned elsewhere by configfs */
 951         ctl_cls[1] = (struct uvc_descriptor_header *)cd;
 952         ctl_cls[2] = (struct uvc_descriptor_header *)pd;
 953         ctl_cls[3] = (struct uvc_descriptor_header *)od;
 954         ctl_cls[4] = NULL;      /* NULL-terminate */
 955         opts->ss_control =
 956                 (const struct uvc_descriptor_header * const *)ctl_cls;
 957
 958         INIT_LIST_HEAD(&opts->extension_units);
 959
 960         opts->streaming_interval = 1;
 961         opts->streaming_maxpacket = 1024;
 962         snprintf(opts->function_name, sizeof(opts->function_name), "UVC Camera");
 963
 964         ret = uvcg_attach_configfs(opts);
 965         if (ret < 0) {
 966                 kfree(opts);
 967                 return ERR_PTR(ret);
 968         }
 969
 970         return &opts->func_inst;
 971 }
 972
 973 static void uvc_free(struct usb_function *f)
 974 {
 975         struct uvc_device *uvc = to_uvc(f);
 976         struct f_uvc_opts *opts = container_of(f->fi, struct f_uvc_opts,
 977                                                func_inst);
 978         if (!opts->header)
 979                 config_item_put(&uvc->header->item);
 980         --opts->refcnt;
 981         kfree(uvc);
 982 }
 983
 984 static void uvc_function_unbind(struct usb_configuration *c,
 985                                 struct usb_function *f)
 986 {
 987         struct usb_composite_dev *cdev = c->cdev;
 988         struct uvc_device *uvc = to_uvc(f);
 989         struct uvc_video *video = &uvc->video;
 990         long wait_ret = 1;
 991
 992         uvcg_info(f, "%s()\n", __func__);
 993
 994         if (video->async_wq)
 995                 destroy_workqueue(video->async_wq);
 996
 997         /*
 998          * If we know we're connected via v4l2, then there should be a cleanup
 999          * of the device from userspace either via UVC_EVENT_DISCONNECT or
1000          * though the video device removal uevent. Allow some time for the
1001          * application to close out before things get deleted.
1002          */
1003         if (uvc->func_connected) {
1004                 uvcg_dbg(f, "waiting for clean disconnect\n");
1005                 wait_ret = wait_event_interruptible_timeout(uvc->func_connected_queue,
1006                                 uvc->func_connected == false, msecs_to_jiffies(500));
1007                 uvcg_dbg(f, "done waiting with ret: %ld\n", wait_ret);
1008         }
1009
1010         device_remove_file(&uvc->vdev.dev, &dev_attr_function_name);
1011         video_unregister_device(&uvc->vdev);
1012         v4l2_device_unregister(&uvc->v4l2_dev);
1013
1014         if (uvc->func_connected) {
1015                 /*
1016                  * Wait for the release to occur to ensure there are no longer any
1017                  * pending operations that may cause panics when resources are cleaned
1018                  * up.
1019                  */
1020                 uvcg_warn(f, "%s no clean disconnect, wait for release\n", __func__);
1021                 wait_ret = wait_event_interruptible_timeout(uvc->func_connected_queue,
1022                                 uvc->func_connected == false, msecs_to_jiffies(1000));
1023                 uvcg_dbg(f, "done waiting for release with ret: %ld\n", wait_ret);
1024         }
1025
1026         usb_ep_free_request(cdev->gadget->ep0, uvc->control_req);
1027         kfree(uvc->control_buf);
1028
1029         usb_free_all_descriptors(f);
1030 }
1031
1032 static struct usb_function *uvc_alloc(struct usb_function_instance *fi)
1033 {
1034         struct uvc_device *uvc;
1035         struct f_uvc_opts *opts;
1036         struct uvc_descriptor_header **strm_cls;
1037         struct config_item *streaming, *header, *h;
1038
1039         uvc = kzalloc(sizeof(*uvc), GFP_KERNEL);
1040         if (uvc == NULL)
1041                 return ERR_PTR(-ENOMEM);
1042
1043         mutex_init(&uvc->video.mutex);
1044         uvc->state = UVC_STATE_DISCONNECTED;
1045         init_waitqueue_head(&uvc->func_connected_queue);
1046         opts = fi_to_f_uvc_opts(fi);
1047
1048         mutex_lock(&opts->lock);
1049         if (opts->uvc_fs_streaming_cls) {
1050                 strm_cls = opts->uvc_fs_streaming_cls;
1051                 opts->fs_streaming =
1052                         (const struct uvc_descriptor_header * const *)strm_cls;
1053         }
1054         if (opts->uvc_hs_streaming_cls) {
1055                 strm_cls = opts->uvc_hs_streaming_cls;
1056                 opts->hs_streaming =
1057                         (const struct uvc_descriptor_header * const *)strm_cls;
1058         }
1059         if (opts->uvc_ss_streaming_cls) {
1060                 strm_cls = opts->uvc_ss_streaming_cls;
1061                 opts->ss_streaming =
1062                         (const struct uvc_descriptor_header * const *)strm_cls;
1063         }
1064
1065         uvc->desc.fs_control = opts->fs_control;
1066         uvc->desc.ss_control = opts->ss_control;
1067         uvc->desc.fs_streaming = opts->fs_streaming;
1068         uvc->desc.hs_streaming = opts->hs_streaming;
1069         uvc->desc.ss_streaming = opts->ss_streaming;
1070
1071         if (opts->header) {
1072                 uvc->header = opts->header;
1073         } else {
1074                 streaming = config_group_find_item(&opts->func_inst.group, "streaming");
1075                 if (!streaming)
1076                         goto err_config;
1077
1078                 header = config_group_find_item(to_config_group(streaming), "header");
1079                 config_item_put(streaming);
1080                 if (!header)
1081                         goto err_config;
1082
1083                 h = config_group_find_item(to_config_group(header), "h");
1084                 config_item_put(header);
1085                 if (!h)
1086                         goto err_config;
1087
1088                 uvc->header = to_uvcg_streaming_header(h);
1089                 if (!uvc->header->linked) {
1090                         mutex_unlock(&opts->lock);
1091                         kfree(uvc);
1092                         return ERR_PTR(-EBUSY);
1093                 }
1094         }
1095
1096         uvc->desc.extension_units = &opts->extension_units;
1097
1098         ++opts->refcnt;
1099         mutex_unlock(&opts->lock);
1100
1101         /* Register the function. */
1102         uvc->func.name = "uvc";
1103         uvc->func.bind = uvc_function_bind;
1104         uvc->func.unbind = uvc_function_unbind;
1105         uvc->func.get_alt = uvc_function_get_alt;
1106         uvc->func.set_alt = uvc_function_set_alt;
1107         uvc->func.disable = uvc_function_disable;
1108         uvc->func.setup = uvc_function_setup;
1109         uvc->func.free_func = uvc_free;
1110         uvc->func.bind_deactivated = true;
1111
1112         return &uvc->func;
1113
1114 err_config:
1115         mutex_unlock(&opts->lock);
1116         kfree(uvc);
1117         return ERR_PTR(-ENOENT);
1118 }
1119
1120 DECLARE_USB_FUNCTION_INIT(uvc, uvc_alloc_inst, uvc_alloc);
1121 MODULE_LICENSE("GPL");
1122 MODULE_AUTHOR("Laurent Pinchart");