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)
 267 {
 268         struct usb_composite_dev *cdev = uvc->func.config->cdev;
 269
 270         usb_composite_setup_continue(cdev);
 271 }
 272
 273 static int
 274 uvc_function_get_alt(struct usb_function *f, unsigned interface)
 275 {
 276         struct uvc_device *uvc = to_uvc(f);
 277
 278         uvcg_info(f, "%s(%u)\n", __func__, interface);
 279
 280         if (interface == uvc->control_intf)
 281                 return 0;
 282         else if (interface != uvc->streaming_intf)
 283                 return -EINVAL;
 284         else
 285                 return uvc->video.ep->enabled ? 1 : 0;
 286 }
 287
 288 static int
 289 uvc_function_set_alt(struct usb_function *f, unsigned interface, unsigned alt)
 290 {
 291         struct uvc_device *uvc = to_uvc(f);
 292         struct usb_composite_dev *cdev = f->config->cdev;
 293         struct v4l2_event v4l2_event;
 294         struct uvc_event *uvc_event = (void *)&v4l2_event.u.data;
 295         int ret;
 296
 297         uvcg_info(f, "%s(%u, %u)\n", __func__, interface, alt);
 298
 299         if (interface == uvc->control_intf) {
 300                 if (alt)
 301                         return -EINVAL;
 302
 303                 if (uvc->enable_interrupt_ep) {
 304                         uvcg_info(f, "reset UVC interrupt endpoint\n");
 305                         usb_ep_disable(uvc->interrupt_ep);
 306
 307                         if (!uvc->interrupt_ep->desc)
 308                                 if (config_ep_by_speed(cdev->gadget, f,
 309                                                        uvc->interrupt_ep))
 310                                         return -EINVAL;
 311
 312                         usb_ep_enable(uvc->interrupt_ep);
 313                 }
 314
 315                 if (uvc->state == UVC_STATE_DISCONNECTED) {
 316                         memset(&v4l2_event, 0, sizeof(v4l2_event));
 317                         v4l2_event.type = UVC_EVENT_CONNECT;
 318                         uvc_event->speed = cdev->gadget->speed;
 319                         v4l2_event_queue(&uvc->vdev, &v4l2_event);
 320
 321                         uvc->state = UVC_STATE_CONNECTED;
 322                 }
 323
 324                 return 0;
 325         }
 326
 327         if (interface != uvc->streaming_intf)
 328                 return -EINVAL;
 329
 330         /* TODO
 331         if (usb_endpoint_xfer_bulk(&uvc->desc.vs_ep))
 332                 return alt ? -EINVAL : 0;
 333         */
 334
 335         switch (alt) {
 336         case 0:
 337                 if (uvc->state != UVC_STATE_STREAMING)
 338                         return 0;
 339
 340                 if (uvc->video.ep)
 341                         usb_ep_disable(uvc->video.ep);
 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                 uvc->state = UVC_STATE_CONNECTED;
 348                 return 0;
 349
 350         case 1:
 351                 if (uvc->state != UVC_STATE_CONNECTED)
 352                         return 0;
 353
 354                 if (!uvc->video.ep)
 355                         return -EINVAL;
 356
 357                 uvcg_info(f, "reset UVC\n");
 358                 usb_ep_disable(uvc->video.ep);
 359
 360                 ret = config_ep_by_speed(f->config->cdev->gadget,
 361                                 &(uvc->func), uvc->video.ep);
 362                 if (ret)
 363                         return ret;
 364                 usb_ep_enable(uvc->video.ep);
 365
 366                 memset(&v4l2_event, 0, sizeof(v4l2_event));
 367                 v4l2_event.type = UVC_EVENT_STREAMON;
 368                 v4l2_event_queue(&uvc->vdev, &v4l2_event);
 369                 return USB_GADGET_DELAYED_STATUS;
 370
 371         default:
 372                 return -EINVAL;
 373         }
 374 }
 375
 376 static void
 377 uvc_function_disable(struct usb_function *f)
 378 {
 379         struct uvc_device *uvc = to_uvc(f);
 380         struct v4l2_event v4l2_event;
 381
 382         uvcg_info(f, "%s()\n", __func__);
 383
 384         memset(&v4l2_event, 0, sizeof(v4l2_event));
 385         v4l2_event.type = UVC_EVENT_DISCONNECT;
 386         v4l2_event_queue(&uvc->vdev, &v4l2_event);
 387
 388         uvc->state = UVC_STATE_DISCONNECTED;
 389
 390         usb_ep_disable(uvc->video.ep);
 391         if (uvc->enable_interrupt_ep)
 392                 usb_ep_disable(uvc->interrupt_ep);
 393 }
 394
 395 /* --------------------------------------------------------------------------
 396  * Connection / disconnection
 397  */
 398
 399 void
 400 uvc_function_connect(struct uvc_device *uvc)
 401 {
 402         int ret;
 403
 404         if ((ret = usb_function_activate(&uvc->func)) < 0)
 405                 uvcg_info(&uvc->func, "UVC connect failed with %d\n", ret);
 406 }
 407
 408 void
 409 uvc_function_disconnect(struct uvc_device *uvc)
 410 {
 411         int ret;
 412
 413         if ((ret = usb_function_deactivate(&uvc->func)) < 0)
 414                 uvcg_info(&uvc->func, "UVC disconnect failed with %d\n", ret);
 415 }
 416
 417 /* --------------------------------------------------------------------------
 418  * USB probe and disconnect
 419  */
 420
 421 static ssize_t function_name_show(struct device *dev,
 422                                   struct device_attribute *attr, char *buf)
 423 {
 424         struct uvc_device *uvc = dev_get_drvdata(dev);
 425
 426         return sprintf(buf, "%s\n", uvc->func.fi->group.cg_item.ci_name);
 427 }
 428
 429 static DEVICE_ATTR_RO(function_name);
 430
 431 static int
 432 uvc_register_video(struct uvc_device *uvc)
 433 {
 434         struct usb_composite_dev *cdev = uvc->func.config->cdev;
 435         int ret;
 436
 437         /* TODO reference counting. */
 438         memset(&uvc->vdev, 0, sizeof(uvc->vdev));
 439         uvc->vdev.v4l2_dev = &uvc->v4l2_dev;
 440         uvc->vdev.v4l2_dev->dev = &cdev->gadget->dev;
 441         uvc->vdev.fops = &uvc_v4l2_fops;
 442         uvc->vdev.ioctl_ops = &uvc_v4l2_ioctl_ops;
 443         uvc->vdev.release = video_device_release_empty;
 444         uvc->vdev.vfl_dir = VFL_DIR_TX;
 445         uvc->vdev.lock = &uvc->video.mutex;
 446         uvc->vdev.device_caps = V4L2_CAP_VIDEO_OUTPUT | V4L2_CAP_STREAMING;
 447         strscpy(uvc->vdev.name, cdev->gadget->name, sizeof(uvc->vdev.name));
 448
 449         video_set_drvdata(&uvc->vdev, uvc);
 450
 451         ret = video_register_device(&uvc->vdev, VFL_TYPE_VIDEO, -1);
 452         if (ret < 0)
 453                 return ret;
 454
 455         ret = device_create_file(&uvc->vdev.dev, &dev_attr_function_name);
 456         if (ret < 0) {
 457                 video_unregister_device(&uvc->vdev);
 458                 return ret;
 459         }
 460
 461         return 0;
 462 }
 463
 464 #define UVC_COPY_DESCRIPTOR(mem, dst, desc) \
 465         do { \
 466                 memcpy(mem, desc, (desc)->bLength); \
 467                 *(dst)++ = mem; \
 468                 mem += (desc)->bLength; \
 469         } while (0);
 470
 471 #define UVC_COPY_DESCRIPTORS(mem, dst, src) \
 472         do { \
 473                 const struct usb_descriptor_header * const *__src; \
 474                 for (__src = src; *__src; ++__src) { \
 475                         memcpy(mem, *__src, (*__src)->bLength); \
 476                         *dst++ = mem; \
 477                         mem += (*__src)->bLength; \
 478                 } \
 479         } while (0)
 480
 481 #define UVC_COPY_XU_DESCRIPTOR(mem, dst, desc)                                  \
 482         do {                                                                    \
 483                 *(dst)++ = mem;                                                 \
 484                 memcpy(mem, desc, 22); /* bLength to bNrInPins */               \
 485                 mem += 22;                                                      \
 486                                                                                 \
 487                 memcpy(mem, (desc)->baSourceID, (desc)->bNrInPins);             \
 488                 mem += (desc)->bNrInPins;                                       \
 489                                                                                 \
 490                 memcpy(mem, &(desc)->bControlSize, 1);                          \
 491                 mem++;                                                          \
 492                                                                                 \
 493                 memcpy(mem, (desc)->bmControls, (desc)->bControlSize);          \
 494                 mem += (desc)->bControlSize;                                    \
 495                                                                                 \
 496                 memcpy(mem, &(desc)->iExtension, 1);                            \
 497                 mem++;                                                          \
 498         } while (0)
 499
 500 static struct usb_descriptor_header **
 501 uvc_copy_descriptors(struct uvc_device *uvc, enum usb_device_speed speed)
 502 {
 503         struct uvc_input_header_descriptor *uvc_streaming_header;
 504         struct uvc_header_descriptor *uvc_control_header;
 505         const struct uvc_descriptor_header * const *uvc_control_desc;
 506         const struct uvc_descriptor_header * const *uvc_streaming_cls;
 507         const struct usb_descriptor_header * const *uvc_streaming_std;
 508         const struct usb_descriptor_header * const *src;
 509         struct usb_descriptor_header **dst;
 510         struct usb_descriptor_header **hdr;
 511         struct uvcg_extension *xu;
 512         unsigned int control_size;
 513         unsigned int streaming_size;
 514         unsigned int n_desc;
 515         unsigned int bytes;
 516         void *mem;
 517
 518         switch (speed) {
 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                         bytes += uvc_ss_interrupt_comp.bLength;
 569                         n_desc += 1;
 570                 }
 571         }
 572
 573         for (src = (const struct usb_descriptor_header **)uvc_control_desc;
 574              *src; ++src) {
 575                 control_size += (*src)->bLength;
 576                 bytes += (*src)->bLength;
 577                 n_desc++;
 578         }
 579
 580         list_for_each_entry(xu, uvc->desc.extension_units, list) {
 581                 control_size += xu->desc.bLength;
 582                 bytes += xu->desc.bLength;
 583                 n_desc++;
 584         }
 585
 586         for (src = (const struct usb_descriptor_header **)uvc_streaming_cls;
 587              *src; ++src) {
 588                 streaming_size += (*src)->bLength;
 589                 bytes += (*src)->bLength;
 590                 n_desc++;
 591         }
 592         for (src = uvc_streaming_std; *src; ++src) {
 593                 bytes += (*src)->bLength;
 594                 n_desc++;
 595         }
 596
 597         mem = kmalloc((n_desc + 1) * sizeof(*src) + bytes, GFP_KERNEL);
 598         if (mem == NULL)
 599                 return NULL;
 600
 601         hdr = mem;
 602         dst = mem;
 603         mem += (n_desc + 1) * sizeof(*src);
 604
 605         /* Copy the descriptors. */
 606         UVC_COPY_DESCRIPTOR(mem, dst, &uvc_iad);
 607         UVC_COPY_DESCRIPTOR(mem, dst, &uvc_control_intf);
 608
 609         uvc_control_header = mem;
 610         UVC_COPY_DESCRIPTORS(mem, dst,
 611                 (const struct usb_descriptor_header **)uvc_control_desc);
 612
 613         list_for_each_entry(xu, uvc->desc.extension_units, list)
 614                 UVC_COPY_XU_DESCRIPTOR(mem, dst, &xu->desc);
 615
 616         uvc_control_header->wTotalLength = cpu_to_le16(control_size);
 617         uvc_control_header->bInCollection = 1;
 618         uvc_control_header->baInterfaceNr[0] = uvc->streaming_intf;
 619
 620         if (uvc->enable_interrupt_ep) {
 621                 UVC_COPY_DESCRIPTOR(mem, dst, &uvc_interrupt_ep);
 622                 if (speed == USB_SPEED_SUPER)
 623                         UVC_COPY_DESCRIPTOR(mem, dst, &uvc_ss_interrupt_comp);
 624
 625                 UVC_COPY_DESCRIPTOR(mem, dst, &uvc_interrupt_cs_ep);
 626         }
 627
 628         UVC_COPY_DESCRIPTOR(mem, dst, &uvc_streaming_intf_alt0);
 629
 630         uvc_streaming_header = mem;
 631         UVC_COPY_DESCRIPTORS(mem, dst,
 632                 (const struct usb_descriptor_header**)uvc_streaming_cls);
 633         uvc_streaming_header->wTotalLength = cpu_to_le16(streaming_size);
 634         uvc_streaming_header->bEndpointAddress = uvc->video.ep->address;
 635
 636         UVC_COPY_DESCRIPTORS(mem, dst, uvc_streaming_std);
 637
 638         *dst = NULL;
 639         return hdr;
 640 }
 641
 642 static int
 643 uvc_function_bind(struct usb_configuration *c, struct usb_function *f)
 644 {
 645         struct usb_composite_dev *cdev = c->cdev;
 646         struct uvc_device *uvc = to_uvc(f);
 647         struct uvcg_extension *xu;
 648         struct usb_string *us;
 649         unsigned int max_packet_mult;
 650         unsigned int max_packet_size;
 651         struct usb_ep *ep;
 652         struct f_uvc_opts *opts;
 653         int ret = -EINVAL;
 654
 655         uvcg_info(f, "%s()\n", __func__);
 656
 657         opts = fi_to_f_uvc_opts(f->fi);
 658         /* Sanity check the streaming endpoint module parameters. */
 659         opts->streaming_interval = clamp(opts->streaming_interval, 1U, 16U);
 660         opts->streaming_maxpacket = clamp(opts->streaming_maxpacket, 1U, 3072U);
 661         opts->streaming_maxburst = min(opts->streaming_maxburst, 15U);
 662
 663         /* For SS, wMaxPacketSize has to be 1024 if bMaxBurst is not 0 */
 664         if (opts->streaming_maxburst &&
 665             (opts->streaming_maxpacket % 1024) != 0) {
 666                 opts->streaming_maxpacket = roundup(opts->streaming_maxpacket, 1024);
 667                 uvcg_info(f, "overriding streaming_maxpacket to %d\n",
 668                           opts->streaming_maxpacket);
 669         }
 670
 671         /*
 672          * Fill in the FS/HS/SS Video Streaming specific descriptors from the
 673          * module parameters.
 674          *
 675          * NOTE: We assume that the user knows what they are doing and won't
 676          * give parameters that their UDC doesn't support.
 677          */
 678         if (opts->streaming_maxpacket <= 1024) {
 679                 max_packet_mult = 1;
 680                 max_packet_size = opts->streaming_maxpacket;
 681         } else if (opts->streaming_maxpacket <= 2048) {
 682                 max_packet_mult = 2;
 683                 max_packet_size = opts->streaming_maxpacket / 2;
 684         } else {
 685                 max_packet_mult = 3;
 686                 max_packet_size = opts->streaming_maxpacket / 3;
 687         }
 688
 689         uvc_fs_streaming_ep.wMaxPacketSize =
 690                 cpu_to_le16(min(opts->streaming_maxpacket, 1023U));
 691         uvc_fs_streaming_ep.bInterval = opts->streaming_interval;
 692
 693         uvc_hs_streaming_ep.wMaxPacketSize =
 694                 cpu_to_le16(max_packet_size | ((max_packet_mult - 1) << 11));
 695
 696         /* A high-bandwidth endpoint must specify a bInterval value of 1 */
 697         if (max_packet_mult > 1)
 698                 uvc_hs_streaming_ep.bInterval = 1;
 699         else
 700                 uvc_hs_streaming_ep.bInterval = opts->streaming_interval;
 701
 702         uvc_ss_streaming_ep.wMaxPacketSize = cpu_to_le16(max_packet_size);
 703         uvc_ss_streaming_ep.bInterval = opts->streaming_interval;
 704         uvc_ss_streaming_comp.bmAttributes = max_packet_mult - 1;
 705         uvc_ss_streaming_comp.bMaxBurst = opts->streaming_maxburst;
 706         uvc_ss_streaming_comp.wBytesPerInterval =
 707                 cpu_to_le16(max_packet_size * max_packet_mult *
 708                             (opts->streaming_maxburst + 1));
 709
 710         /* Allocate endpoints. */
 711         if (opts->enable_interrupt_ep) {
 712                 ep = usb_ep_autoconfig(cdev->gadget, &uvc_interrupt_ep);
 713                 if (!ep) {
 714                         uvcg_info(f, "Unable to allocate interrupt EP\n");
 715                         goto error;
 716                 }
 717                 uvc->interrupt_ep = ep;
 718                 uvc_control_intf.bNumEndpoints = 1;
 719         }
 720         uvc->enable_interrupt_ep = opts->enable_interrupt_ep;
 721
 722         /*
 723          * gadget_is_{super|dual}speed() API check UDC controller capitblity. It should pass down
 724          * highest speed endpoint descriptor to UDC controller. So UDC controller driver can reserve
 725          * enough resource at check_config(), especially mult and maxburst. So UDC driver (such as
 726          * cdns3) can know need at least (mult + 1) * (maxburst + 1) * wMaxPacketSize internal
 727          * memory for this uvc functions. This is the only straightforward method to resolve the UDC
 728          * resource allocation issue in the current gadget framework.
 729          */
 730         if (gadget_is_superspeed(c->cdev->gadget))
 731                 ep = usb_ep_autoconfig_ss(cdev->gadget, &uvc_ss_streaming_ep,
 732                                           &uvc_ss_streaming_comp);
 733         else if (gadget_is_dualspeed(cdev->gadget))
 734                 ep = usb_ep_autoconfig(cdev->gadget, &uvc_hs_streaming_ep);
 735         else
 736                 ep = usb_ep_autoconfig(cdev->gadget, &uvc_fs_streaming_ep);
 737
 738         if (!ep) {
 739                 uvcg_info(f, "Unable to allocate streaming EP\n");
 740                 goto error;
 741         }
 742         uvc->video.ep = ep;
 743
 744         uvc_fs_streaming_ep.bEndpointAddress = uvc->video.ep->address;
 745         uvc_hs_streaming_ep.bEndpointAddress = uvc->video.ep->address;
 746         uvc_ss_streaming_ep.bEndpointAddress = uvc->video.ep->address;
 747
 748         /*
 749          * XUs can have an arbitrary string descriptor describing them. If they
 750          * have one pick up the ID.
 751          */
 752         list_for_each_entry(xu, &opts->extension_units, list)
 753                 if (xu->string_descriptor_index)
 754                         xu->desc.iExtension = cdev->usb_strings[xu->string_descriptor_index].id;
 755
 756         /*
 757          * We attach the hard-coded defaults incase the user does not provide
 758          * any more appropriate strings through configfs.
 759          */
 760         uvc_en_us_strings[UVC_STRING_CONTROL_IDX].s = opts->function_name;
 761         us = usb_gstrings_attach(cdev, uvc_function_strings,
 762                                  ARRAY_SIZE(uvc_en_us_strings));
 763         if (IS_ERR(us)) {
 764                 ret = PTR_ERR(us);
 765                 goto error;
 766         }
 767
 768         uvc_iad.iFunction = opts->iad_index ? cdev->usb_strings[opts->iad_index].id :
 769                             us[UVC_STRING_CONTROL_IDX].id;
 770         uvc_streaming_intf_alt0.iInterface = opts->vs0_index ?
 771                                              cdev->usb_strings[opts->vs0_index].id :
 772                                              us[UVC_STRING_STREAMING_IDX].id;
 773         uvc_streaming_intf_alt1.iInterface = opts->vs1_index ?
 774                                              cdev->usb_strings[opts->vs1_index].id :
 775                                              us[UVC_STRING_STREAMING_IDX].id;
 776
 777         /* Allocate interface IDs. */
 778         if ((ret = usb_interface_id(c, f)) < 0)
 779                 goto error;
 780         uvc_iad.bFirstInterface = ret;
 781         uvc_control_intf.bInterfaceNumber = ret;
 782         uvc->control_intf = ret;
 783         opts->control_interface = ret;
 784
 785         if ((ret = usb_interface_id(c, f)) < 0)
 786                 goto error;
 787         uvc_streaming_intf_alt0.bInterfaceNumber = ret;
 788         uvc_streaming_intf_alt1.bInterfaceNumber = ret;
 789         uvc->streaming_intf = ret;
 790         opts->streaming_interface = ret;
 791
 792         /* Copy descriptors */
 793         f->fs_descriptors = uvc_copy_descriptors(uvc, USB_SPEED_FULL);
 794         if (IS_ERR(f->fs_descriptors)) {
 795                 ret = PTR_ERR(f->fs_descriptors);
 796                 f->fs_descriptors = NULL;
 797                 goto error;
 798         }
 799
 800         f->hs_descriptors = uvc_copy_descriptors(uvc, USB_SPEED_HIGH);
 801         if (IS_ERR(f->hs_descriptors)) {
 802                 ret = PTR_ERR(f->hs_descriptors);
 803                 f->hs_descriptors = NULL;
 804                 goto error;
 805         }
 806
 807         f->ss_descriptors = uvc_copy_descriptors(uvc, USB_SPEED_SUPER);
 808         if (IS_ERR(f->ss_descriptors)) {
 809                 ret = PTR_ERR(f->ss_descriptors);
 810                 f->ss_descriptors = NULL;
 811                 goto error;
 812         }
 813
 814         /* Preallocate control endpoint request. */
 815         uvc->control_req = usb_ep_alloc_request(cdev->gadget->ep0, GFP_KERNEL);
 816         uvc->control_buf = kmalloc(UVC_MAX_REQUEST_SIZE, GFP_KERNEL);
 817         if (uvc->control_req == NULL || uvc->control_buf == NULL) {
 818                 ret = -ENOMEM;
 819                 goto error;
 820         }
 821
 822         uvc->control_req->buf = uvc->control_buf;
 823         uvc->control_req->complete = uvc_function_ep0_complete;
 824         uvc->control_req->context = uvc;
 825
 826         if (v4l2_device_register(&cdev->gadget->dev, &uvc->v4l2_dev)) {
 827                 uvcg_err(f, "failed to register V4L2 device\n");
 828                 goto error;
 829         }
 830
 831         /* Initialise video. */
 832         ret = uvcg_video_init(&uvc->video, uvc);
 833         if (ret < 0)
 834                 goto v4l2_error;
 835
 836         /* Register a V4L2 device. */
 837         ret = uvc_register_video(uvc);
 838         if (ret < 0) {
 839                 uvcg_err(f, "failed to register video device\n");
 840                 goto v4l2_error;
 841         }
 842
 843         return 0;
 844
 845 v4l2_error:
 846         v4l2_device_unregister(&uvc->v4l2_dev);
 847 error:
 848         if (uvc->control_req)
 849                 usb_ep_free_request(cdev->gadget->ep0, uvc->control_req);
 850         kfree(uvc->control_buf);
 851
 852         usb_free_all_descriptors(f);
 853         return ret;
 854 }
 855
 856 /* --------------------------------------------------------------------------
 857  * USB gadget function
 858  */
 859
 860 static void uvc_free_inst(struct usb_function_instance *f)
 861 {
 862         struct f_uvc_opts *opts = fi_to_f_uvc_opts(f);
 863
 864         mutex_destroy(&opts->lock);
 865         kfree(opts);
 866 }
 867
 868 static struct usb_function_instance *uvc_alloc_inst(void)
 869 {
 870         struct f_uvc_opts *opts;
 871         struct uvc_camera_terminal_descriptor *cd;
 872         struct uvc_processing_unit_descriptor *pd;
 873         struct uvc_output_terminal_descriptor *od;
 874         struct uvc_descriptor_header **ctl_cls;
 875         int ret;
 876
 877         opts = kzalloc(sizeof(*opts), GFP_KERNEL);
 878         if (!opts)
 879                 return ERR_PTR(-ENOMEM);
 880         opts->func_inst.free_func_inst = uvc_free_inst;
 881         mutex_init(&opts->lock);
 882
 883         cd = &opts->uvc_camera_terminal;
 884         cd->bLength                     = UVC_DT_CAMERA_TERMINAL_SIZE(3);
 885         cd->bDescriptorType             = USB_DT_CS_INTERFACE;
 886         cd->bDescriptorSubType          = UVC_VC_INPUT_TERMINAL;
 887         cd->bTerminalID                 = 1;
 888         cd->wTerminalType               = cpu_to_le16(0x0201);
 889         cd->bAssocTerminal              = 0;
 890         cd->iTerminal                   = 0;
 891         cd->wObjectiveFocalLengthMin    = cpu_to_le16(0);
 892         cd->wObjectiveFocalLengthMax    = cpu_to_le16(0);
 893         cd->wOcularFocalLength          = cpu_to_le16(0);
 894         cd->bControlSize                = 3;
 895         cd->bmControls[0]               = 2;
 896         cd->bmControls[1]               = 0;
 897         cd->bmControls[2]               = 0;
 898
 899         pd = &opts->uvc_processing;
 900         pd->bLength                     = UVC_DT_PROCESSING_UNIT_SIZE(2);
 901         pd->bDescriptorType             = USB_DT_CS_INTERFACE;
 902         pd->bDescriptorSubType          = UVC_VC_PROCESSING_UNIT;
 903         pd->bUnitID                     = 2;
 904         pd->bSourceID                   = 1;
 905         pd->wMaxMultiplier              = cpu_to_le16(16*1024);
 906         pd->bControlSize                = 2;
 907         pd->bmControls[0]               = 1;
 908         pd->bmControls[1]               = 0;
 909         pd->iProcessing                 = 0;
 910         pd->bmVideoStandards            = 0;
 911
 912         od = &opts->uvc_output_terminal;
 913         od->bLength                     = UVC_DT_OUTPUT_TERMINAL_SIZE;
 914         od->bDescriptorType             = USB_DT_CS_INTERFACE;
 915         od->bDescriptorSubType          = UVC_VC_OUTPUT_TERMINAL;
 916         od->bTerminalID                 = 3;
 917         od->wTerminalType               = cpu_to_le16(0x0101);
 918         od->bAssocTerminal              = 0;
 919         od->bSourceID                   = 2;
 920         od->iTerminal                   = 0;
 921
 922         /*
 923          * With the ability to add XUs to the UVC function graph, we need to be
 924          * able to allocate unique unit IDs to them. The IDs are 1-based, with
 925          * the CT, PU and OT above consuming the first 3.
 926          */
 927         opts->last_unit_id              = 3;
 928
 929         /* Prepare fs control class descriptors for configfs-based gadgets */
 930         ctl_cls = opts->uvc_fs_control_cls;
 931         ctl_cls[0] = NULL;      /* assigned elsewhere by configfs */
 932         ctl_cls[1] = (struct uvc_descriptor_header *)cd;
 933         ctl_cls[2] = (struct uvc_descriptor_header *)pd;
 934         ctl_cls[3] = (struct uvc_descriptor_header *)od;
 935         ctl_cls[4] = NULL;      /* NULL-terminate */
 936         opts->fs_control =
 937                 (const struct uvc_descriptor_header * const *)ctl_cls;
 938
 939         /* Prepare hs control class descriptors for configfs-based gadgets */
 940         ctl_cls = opts->uvc_ss_control_cls;
 941         ctl_cls[0] = NULL;      /* assigned elsewhere by configfs */
 942         ctl_cls[1] = (struct uvc_descriptor_header *)cd;
 943         ctl_cls[2] = (struct uvc_descriptor_header *)pd;
 944         ctl_cls[3] = (struct uvc_descriptor_header *)od;
 945         ctl_cls[4] = NULL;      /* NULL-terminate */
 946         opts->ss_control =
 947                 (const struct uvc_descriptor_header * const *)ctl_cls;
 948
 949         INIT_LIST_HEAD(&opts->extension_units);
 950
 951         opts->streaming_interval = 1;
 952         opts->streaming_maxpacket = 1024;
 953         snprintf(opts->function_name, sizeof(opts->function_name), "UVC Camera");
 954
 955         ret = uvcg_attach_configfs(opts);
 956         if (ret < 0) {
 957                 kfree(opts);
 958                 return ERR_PTR(ret);
 959         }
 960
 961         return &opts->func_inst;
 962 }
 963
 964 static void uvc_free(struct usb_function *f)
 965 {
 966         struct uvc_device *uvc = to_uvc(f);
 967         struct f_uvc_opts *opts = container_of(f->fi, struct f_uvc_opts,
 968                                                func_inst);
 969         config_item_put(&uvc->header->item);
 970         --opts->refcnt;
 971         kfree(uvc);
 972 }
 973
 974 static void uvc_function_unbind(struct usb_configuration *c,
 975                                 struct usb_function *f)
 976 {
 977         struct usb_composite_dev *cdev = c->cdev;
 978         struct uvc_device *uvc = to_uvc(f);
 979         struct uvc_video *video = &uvc->video;
 980         long wait_ret = 1;
 981
 982         uvcg_info(f, "%s()\n", __func__);
 983
 984         if (video->async_wq)
 985                 destroy_workqueue(video->async_wq);
 986
 987         /*
 988          * If we know we're connected via v4l2, then there should be a cleanup
 989          * of the device from userspace either via UVC_EVENT_DISCONNECT or
 990          * though the video device removal uevent. Allow some time for the
 991          * application to close out before things get deleted.
 992          */
 993         if (uvc->func_connected) {
 994                 uvcg_dbg(f, "waiting for clean disconnect\n");
 995                 wait_ret = wait_event_interruptible_timeout(uvc->func_connected_queue,
 996                                 uvc->func_connected == false, msecs_to_jiffies(500));
 997                 uvcg_dbg(f, "done waiting with ret: %ld\n", wait_ret);
 998         }
 999
1000         device_remove_file(&uvc->vdev.dev, &dev_attr_function_name);
1001         video_unregister_device(&uvc->vdev);
1002         v4l2_device_unregister(&uvc->v4l2_dev);
1003
1004         if (uvc->func_connected) {
1005                 /*
1006                  * Wait for the release to occur to ensure there are no longer any
1007                  * pending operations that may cause panics when resources are cleaned
1008                  * up.
1009                  */
1010                 uvcg_warn(f, "%s no clean disconnect, wait for release\n", __func__);
1011                 wait_ret = wait_event_interruptible_timeout(uvc->func_connected_queue,
1012                                 uvc->func_connected == false, msecs_to_jiffies(1000));
1013                 uvcg_dbg(f, "done waiting for release with ret: %ld\n", wait_ret);
1014         }
1015
1016         usb_ep_free_request(cdev->gadget->ep0, uvc->control_req);
1017         kfree(uvc->control_buf);
1018
1019         usb_free_all_descriptors(f);
1020 }
1021
1022 static struct usb_function *uvc_alloc(struct usb_function_instance *fi)
1023 {
1024         struct uvc_device *uvc;
1025         struct f_uvc_opts *opts;
1026         struct uvc_descriptor_header **strm_cls;
1027         struct config_item *streaming, *header, *h;
1028
1029         uvc = kzalloc(sizeof(*uvc), GFP_KERNEL);
1030         if (uvc == NULL)
1031                 return ERR_PTR(-ENOMEM);
1032
1033         mutex_init(&uvc->video.mutex);
1034         uvc->state = UVC_STATE_DISCONNECTED;
1035         init_waitqueue_head(&uvc->func_connected_queue);
1036         opts = fi_to_f_uvc_opts(fi);
1037
1038         mutex_lock(&opts->lock);
1039         if (opts->uvc_fs_streaming_cls) {
1040                 strm_cls = opts->uvc_fs_streaming_cls;
1041                 opts->fs_streaming =
1042                         (const struct uvc_descriptor_header * const *)strm_cls;
1043         }
1044         if (opts->uvc_hs_streaming_cls) {
1045                 strm_cls = opts->uvc_hs_streaming_cls;
1046                 opts->hs_streaming =
1047                         (const struct uvc_descriptor_header * const *)strm_cls;
1048         }
1049         if (opts->uvc_ss_streaming_cls) {
1050                 strm_cls = opts->uvc_ss_streaming_cls;
1051                 opts->ss_streaming =
1052                         (const struct uvc_descriptor_header * const *)strm_cls;
1053         }
1054
1055         uvc->desc.fs_control = opts->fs_control;
1056         uvc->desc.ss_control = opts->ss_control;
1057         uvc->desc.fs_streaming = opts->fs_streaming;
1058         uvc->desc.hs_streaming = opts->hs_streaming;
1059         uvc->desc.ss_streaming = opts->ss_streaming;
1060
1061         streaming = config_group_find_item(&opts->func_inst.group, "streaming");
1062         if (!streaming)
1063                 goto err_config;
1064
1065         header = config_group_find_item(to_config_group(streaming), "header");
1066         config_item_put(streaming);
1067         if (!header)
1068                 goto err_config;
1069
1070         h = config_group_find_item(to_config_group(header), "h");
1071         config_item_put(header);
1072         if (!h)
1073                 goto err_config;
1074
1075         uvc->header = to_uvcg_streaming_header(h);
1076         if (!uvc->header->linked) {
1077                 mutex_unlock(&opts->lock);
1078                 kfree(uvc);
1079                 return ERR_PTR(-EBUSY);
1080         }
1081
1082         uvc->desc.extension_units = &opts->extension_units;
1083
1084         ++opts->refcnt;
1085         mutex_unlock(&opts->lock);
1086
1087         /* Register the function. */
1088         uvc->func.name = "uvc";
1089         uvc->func.bind = uvc_function_bind;
1090         uvc->func.unbind = uvc_function_unbind;
1091         uvc->func.get_alt = uvc_function_get_alt;
1092         uvc->func.set_alt = uvc_function_set_alt;
1093         uvc->func.disable = uvc_function_disable;
1094         uvc->func.setup = uvc_function_setup;
1095         uvc->func.free_func = uvc_free;
1096         uvc->func.bind_deactivated = true;
1097
1098         return &uvc->func;
1099
1100 err_config:
1101         mutex_unlock(&opts->lock);
1102         kfree(uvc);
1103         return ERR_PTR(-ENOENT);
1104 }
1105
1106 DECLARE_USB_FUNCTION_INIT(uvc, uvc_alloc_inst, uvc_alloc);
1107 MODULE_LICENSE("GPL");
1108 MODULE_AUTHOR("Laurent Pinchart");