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 "u_uvc.h"
  28 #include "uvc.h"
  29 #include "uvc_configfs.h"
  30 #include "uvc_v4l2.h"
  31 #include "uvc_video.h"
  32
  33 unsigned int uvc_gadget_trace_param;
  34 module_param_named(trace, uvc_gadget_trace_param, uint, 0644);
  35 MODULE_PARM_DESC(trace, "Trace level bitmask");
  36
  37 /* --------------------------------------------------------------------------
  38  * Function descriptors
  39  */
  40
  41 /* string IDs are assigned dynamically */
  42
  43 #define UVC_STRING_CONTROL_IDX                  0
  44 #define UVC_STRING_STREAMING_IDX                1
  45
  46 static struct usb_string uvc_en_us_strings[] = {
  47         [UVC_STRING_CONTROL_IDX].s = "UVC Camera",
  48         [UVC_STRING_STREAMING_IDX].s = "Video Streaming",
  49         {  }
  50 };
  51
  52 static struct usb_gadget_strings uvc_stringtab = {
  53         .language = 0x0409,     /* en-us */
  54         .strings = uvc_en_us_strings,
  55 };
  56
  57 static struct usb_gadget_strings *uvc_function_strings[] = {
  58         &uvc_stringtab,
  59         NULL,
  60 };
  61
  62 #define UVC_INTF_VIDEO_CONTROL                  0
  63 #define UVC_INTF_VIDEO_STREAMING                1
  64
  65 #define UVC_STATUS_MAX_PACKET_SIZE              16      /* 16 bytes status */
  66
  67 static struct usb_interface_assoc_descriptor uvc_iad = {
  68         .bLength                = sizeof(uvc_iad),
  69         .bDescriptorType        = USB_DT_INTERFACE_ASSOCIATION,
  70         .bFirstInterface        = 0,
  71         .bInterfaceCount        = 2,
  72         .bFunctionClass         = USB_CLASS_VIDEO,
  73         .bFunctionSubClass      = UVC_SC_VIDEO_INTERFACE_COLLECTION,
  74         .bFunctionProtocol      = 0x00,
  75         .iFunction              = 0,
  76 };
  77
  78 static struct usb_interface_descriptor uvc_control_intf = {
  79         .bLength                = USB_DT_INTERFACE_SIZE,
  80         .bDescriptorType        = USB_DT_INTERFACE,
  81         .bInterfaceNumber       = UVC_INTF_VIDEO_CONTROL,
  82         .bAlternateSetting      = 0,
  83         .bNumEndpoints          = 1,
  84         .bInterfaceClass        = USB_CLASS_VIDEO,
  85         .bInterfaceSubClass     = UVC_SC_VIDEOCONTROL,
  86         .bInterfaceProtocol     = 0x00,
  87         .iInterface             = 0,
  88 };
  89
  90 static struct usb_endpoint_descriptor uvc_control_ep = {
  91         .bLength                = USB_DT_ENDPOINT_SIZE,
  92         .bDescriptorType        = USB_DT_ENDPOINT,
  93         .bEndpointAddress       = USB_DIR_IN,
  94         .bmAttributes           = USB_ENDPOINT_XFER_INT,
  95         .wMaxPacketSize         = cpu_to_le16(UVC_STATUS_MAX_PACKET_SIZE),
  96         .bInterval              = 8,
  97 };
  98
  99 static struct usb_ss_ep_comp_descriptor uvc_ss_control_comp = {
 100         .bLength                = sizeof(uvc_ss_control_comp),
 101         .bDescriptorType        = USB_DT_SS_ENDPOINT_COMP,
 102         /* The following 3 values can be tweaked if necessary. */
 103         .bMaxBurst              = 0,
 104         .bmAttributes           = 0,
 105         .wBytesPerInterval      = cpu_to_le16(UVC_STATUS_MAX_PACKET_SIZE),
 106 };
 107
 108 static struct uvc_control_endpoint_descriptor uvc_control_cs_ep = {
 109         .bLength                = UVC_DT_CONTROL_ENDPOINT_SIZE,
 110         .bDescriptorType        = USB_DT_CS_ENDPOINT,
 111         .bDescriptorSubType     = UVC_EP_INTERRUPT,
 112         .wMaxTransferSize       = cpu_to_le16(UVC_STATUS_MAX_PACKET_SIZE),
 113 };
 114
 115 static struct usb_interface_descriptor uvc_streaming_intf_alt0 = {
 116         .bLength                = USB_DT_INTERFACE_SIZE,
 117         .bDescriptorType        = USB_DT_INTERFACE,
 118         .bInterfaceNumber       = UVC_INTF_VIDEO_STREAMING,
 119         .bAlternateSetting      = 0,
 120         .bNumEndpoints          = 0,
 121         .bInterfaceClass        = USB_CLASS_VIDEO,
 122         .bInterfaceSubClass     = UVC_SC_VIDEOSTREAMING,
 123         .bInterfaceProtocol     = 0x00,
 124         .iInterface             = 0,
 125 };
 126
 127 static struct usb_interface_descriptor uvc_streaming_intf_alt1 = {
 128         .bLength                = USB_DT_INTERFACE_SIZE,
 129         .bDescriptorType        = USB_DT_INTERFACE,
 130         .bInterfaceNumber       = UVC_INTF_VIDEO_STREAMING,
 131         .bAlternateSetting      = 1,
 132         .bNumEndpoints          = 1,
 133         .bInterfaceClass        = USB_CLASS_VIDEO,
 134         .bInterfaceSubClass     = UVC_SC_VIDEOSTREAMING,
 135         .bInterfaceProtocol     = 0x00,
 136         .iInterface             = 0,
 137 };
 138
 139 static struct usb_endpoint_descriptor uvc_fs_streaming_ep = {
 140         .bLength                = USB_DT_ENDPOINT_SIZE,
 141         .bDescriptorType        = USB_DT_ENDPOINT,
 142         .bEndpointAddress       = USB_DIR_IN,
 143         .bmAttributes           = USB_ENDPOINT_SYNC_ASYNC
 144                                 | USB_ENDPOINT_XFER_ISOC,
 145         /* The wMaxPacketSize and bInterval values will be initialized from
 146          * module parameters.
 147          */
 148 };
 149
 150 static struct usb_endpoint_descriptor uvc_hs_streaming_ep = {
 151         .bLength                = USB_DT_ENDPOINT_SIZE,
 152         .bDescriptorType        = USB_DT_ENDPOINT,
 153         .bEndpointAddress       = USB_DIR_IN,
 154         .bmAttributes           = USB_ENDPOINT_SYNC_ASYNC
 155                                 | USB_ENDPOINT_XFER_ISOC,
 156         /* The wMaxPacketSize and bInterval values will be initialized from
 157          * module parameters.
 158          */
 159 };
 160
 161 static struct usb_endpoint_descriptor uvc_ss_streaming_ep = {
 162         .bLength                = USB_DT_ENDPOINT_SIZE,
 163         .bDescriptorType        = USB_DT_ENDPOINT,
 164
 165         .bEndpointAddress       = USB_DIR_IN,
 166         .bmAttributes           = USB_ENDPOINT_SYNC_ASYNC
 167                                 | USB_ENDPOINT_XFER_ISOC,
 168         /* The wMaxPacketSize and bInterval values will be initialized from
 169          * module parameters.
 170          */
 171 };
 172
 173 static struct usb_ss_ep_comp_descriptor uvc_ss_streaming_comp = {
 174         .bLength                = sizeof(uvc_ss_streaming_comp),
 175         .bDescriptorType        = USB_DT_SS_ENDPOINT_COMP,
 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 = req->actual;
 217                 memcpy(&uvc_event->data.data, req->buf, req->actual);
 218                 v4l2_event_queue(&uvc->vdev, &v4l2_event);
 219         }
 220 }
 221
 222 static int
 223 uvc_function_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
 224 {
 225         struct uvc_device *uvc = to_uvc(f);
 226         struct v4l2_event v4l2_event;
 227         struct uvc_event *uvc_event = (void *)&v4l2_event.u.data;
 228
 229         if ((ctrl->bRequestType & USB_TYPE_MASK) != USB_TYPE_CLASS) {
 230                 uvcg_info(f, "invalid request type\n");
 231                 return -EINVAL;
 232         }
 233
 234         /* Stall too big requests. */
 235         if (le16_to_cpu(ctrl->wLength) > UVC_MAX_REQUEST_SIZE)
 236                 return -EINVAL;
 237
 238         /* Tell the complete callback to generate an event for the next request
 239          * that will be enqueued by UVCIOC_SEND_RESPONSE.
 240          */
 241         uvc->event_setup_out = !(ctrl->bRequestType & USB_DIR_IN);
 242         uvc->event_length = le16_to_cpu(ctrl->wLength);
 243
 244         memset(&v4l2_event, 0, sizeof(v4l2_event));
 245         v4l2_event.type = UVC_EVENT_SETUP;
 246         memcpy(&uvc_event->req, ctrl, sizeof(uvc_event->req));
 247         v4l2_event_queue(&uvc->vdev, &v4l2_event);
 248
 249         return 0;
 250 }
 251
 252 void uvc_function_setup_continue(struct uvc_device *uvc)
 253 {
 254         struct usb_composite_dev *cdev = uvc->func.config->cdev;
 255
 256         usb_composite_setup_continue(cdev);
 257 }
 258
 259 static int
 260 uvc_function_get_alt(struct usb_function *f, unsigned interface)
 261 {
 262         struct uvc_device *uvc = to_uvc(f);
 263
 264         uvcg_info(f, "%s(%u)\n", __func__, interface);
 265
 266         if (interface == uvc->control_intf)
 267                 return 0;
 268         else if (interface != uvc->streaming_intf)
 269                 return -EINVAL;
 270         else
 271                 return uvc->video.ep->enabled ? 1 : 0;
 272 }
 273
 274 static int
 275 uvc_function_set_alt(struct usb_function *f, unsigned interface, unsigned alt)
 276 {
 277         struct uvc_device *uvc = to_uvc(f);
 278         struct usb_composite_dev *cdev = f->config->cdev;
 279         struct v4l2_event v4l2_event;
 280         struct uvc_event *uvc_event = (void *)&v4l2_event.u.data;
 281         int ret;
 282
 283         uvcg_info(f, "%s(%u, %u)\n", __func__, interface, alt);
 284
 285         if (interface == uvc->control_intf) {
 286                 if (alt)
 287                         return -EINVAL;
 288
 289                 uvcg_info(f, "reset UVC Control\n");
 290                 usb_ep_disable(uvc->control_ep);
 291
 292                 if (!uvc->control_ep->desc)
 293                         if (config_ep_by_speed(cdev->gadget, f, uvc->control_ep))
 294                                 return -EINVAL;
 295
 296                 usb_ep_enable(uvc->control_ep);
 297
 298                 if (uvc->state == UVC_STATE_DISCONNECTED) {
 299                         memset(&v4l2_event, 0, sizeof(v4l2_event));
 300                         v4l2_event.type = UVC_EVENT_CONNECT;
 301                         uvc_event->speed = cdev->gadget->speed;
 302                         v4l2_event_queue(&uvc->vdev, &v4l2_event);
 303
 304                         uvc->state = UVC_STATE_CONNECTED;
 305                 }
 306
 307                 return 0;
 308         }
 309
 310         if (interface != uvc->streaming_intf)
 311                 return -EINVAL;
 312
 313         /* TODO
 314         if (usb_endpoint_xfer_bulk(&uvc->desc.vs_ep))
 315                 return alt ? -EINVAL : 0;
 316         */
 317
 318         switch (alt) {
 319         case 0:
 320                 if (uvc->state != UVC_STATE_STREAMING)
 321                         return 0;
 322
 323                 if (uvc->video.ep)
 324                         usb_ep_disable(uvc->video.ep);
 325
 326                 memset(&v4l2_event, 0, sizeof(v4l2_event));
 327                 v4l2_event.type = UVC_EVENT_STREAMOFF;
 328                 v4l2_event_queue(&uvc->vdev, &v4l2_event);
 329
 330                 uvc->state = UVC_STATE_CONNECTED;
 331                 return 0;
 332
 333         case 1:
 334                 if (uvc->state != UVC_STATE_CONNECTED)
 335                         return 0;
 336
 337                 if (!uvc->video.ep)
 338                         return -EINVAL;
 339
 340                 uvcg_info(f, "reset UVC\n");
 341                 usb_ep_disable(uvc->video.ep);
 342
 343                 ret = config_ep_by_speed(f->config->cdev->gadget,
 344                                 &(uvc->func), uvc->video.ep);
 345                 if (ret)
 346                         return ret;
 347                 usb_ep_enable(uvc->video.ep);
 348
 349                 memset(&v4l2_event, 0, sizeof(v4l2_event));
 350                 v4l2_event.type = UVC_EVENT_STREAMON;
 351                 v4l2_event_queue(&uvc->vdev, &v4l2_event);
 352                 return USB_GADGET_DELAYED_STATUS;
 353
 354         default:
 355                 return -EINVAL;
 356         }
 357 }
 358
 359 static void
 360 uvc_function_disable(struct usb_function *f)
 361 {
 362         struct uvc_device *uvc = to_uvc(f);
 363         struct v4l2_event v4l2_event;
 364
 365         uvcg_info(f, "%s()\n", __func__);
 366
 367         memset(&v4l2_event, 0, sizeof(v4l2_event));
 368         v4l2_event.type = UVC_EVENT_DISCONNECT;
 369         v4l2_event_queue(&uvc->vdev, &v4l2_event);
 370
 371         uvc->state = UVC_STATE_DISCONNECTED;
 372
 373         usb_ep_disable(uvc->video.ep);
 374         usb_ep_disable(uvc->control_ep);
 375 }
 376
 377 /* --------------------------------------------------------------------------
 378  * Connection / disconnection
 379  */
 380
 381 void
 382 uvc_function_connect(struct uvc_device *uvc)
 383 {
 384         int ret;
 385
 386         if ((ret = usb_function_activate(&uvc->func)) < 0)
 387                 uvcg_info(&uvc->func, "UVC connect failed with %d\n", ret);
 388 }
 389
 390 void
 391 uvc_function_disconnect(struct uvc_device *uvc)
 392 {
 393         int ret;
 394
 395         if ((ret = usb_function_deactivate(&uvc->func)) < 0)
 396                 uvcg_info(&uvc->func, "UVC disconnect failed with %d\n", ret);
 397 }
 398
 399 /* --------------------------------------------------------------------------
 400  * USB probe and disconnect
 401  */
 402
 403 static ssize_t function_name_show(struct device *dev,
 404                                   struct device_attribute *attr, char *buf)
 405 {
 406         struct uvc_device *uvc = dev_get_drvdata(dev);
 407
 408         return sprintf(buf, "%s\n", uvc->func.fi->group.cg_item.ci_name);
 409 }
 410
 411 static DEVICE_ATTR_RO(function_name);
 412
 413 static int
 414 uvc_register_video(struct uvc_device *uvc)
 415 {
 416         struct usb_composite_dev *cdev = uvc->func.config->cdev;
 417         int ret;
 418
 419         /* TODO reference counting. */
 420         uvc->vdev.v4l2_dev = &uvc->v4l2_dev;
 421         uvc->vdev.fops = &uvc_v4l2_fops;
 422         uvc->vdev.ioctl_ops = &uvc_v4l2_ioctl_ops;
 423         uvc->vdev.release = video_device_release_empty;
 424         uvc->vdev.vfl_dir = VFL_DIR_TX;
 425         uvc->vdev.lock = &uvc->video.mutex;
 426         uvc->vdev.device_caps = V4L2_CAP_VIDEO_OUTPUT | V4L2_CAP_STREAMING;
 427         strlcpy(uvc->vdev.name, cdev->gadget->name, sizeof(uvc->vdev.name));
 428
 429         video_set_drvdata(&uvc->vdev, uvc);
 430
 431         ret = video_register_device(&uvc->vdev, VFL_TYPE_VIDEO, -1);
 432         if (ret < 0)
 433                 return ret;
 434
 435         ret = device_create_file(&uvc->vdev.dev, &dev_attr_function_name);
 436         if (ret < 0) {
 437                 video_unregister_device(&uvc->vdev);
 438                 return ret;
 439         }
 440
 441         return 0;
 442 }
 443
 444 #define UVC_COPY_DESCRIPTOR(mem, dst, desc) \
 445         do { \
 446                 memcpy(mem, desc, (desc)->bLength); \
 447                 *(dst)++ = mem; \
 448                 mem += (desc)->bLength; \
 449         } while (0);
 450
 451 #define UVC_COPY_DESCRIPTORS(mem, dst, src) \
 452         do { \
 453                 const struct usb_descriptor_header * const *__src; \
 454                 for (__src = src; *__src; ++__src) { \
 455                         memcpy(mem, *__src, (*__src)->bLength); \
 456                         *dst++ = mem; \
 457                         mem += (*__src)->bLength; \
 458                 } \
 459         } while (0)
 460
 461 static struct usb_descriptor_header **
 462 uvc_copy_descriptors(struct uvc_device *uvc, enum usb_device_speed speed)
 463 {
 464         struct uvc_input_header_descriptor *uvc_streaming_header;
 465         struct uvc_header_descriptor *uvc_control_header;
 466         const struct uvc_descriptor_header * const *uvc_control_desc;
 467         const struct uvc_descriptor_header * const *uvc_streaming_cls;
 468         const struct usb_descriptor_header * const *uvc_streaming_std;
 469         const struct usb_descriptor_header * const *src;
 470         struct usb_descriptor_header **dst;
 471         struct usb_descriptor_header **hdr;
 472         unsigned int control_size;
 473         unsigned int streaming_size;
 474         unsigned int n_desc;
 475         unsigned int bytes;
 476         void *mem;
 477
 478         switch (speed) {
 479         case USB_SPEED_SUPER:
 480                 uvc_control_desc = uvc->desc.ss_control;
 481                 uvc_streaming_cls = uvc->desc.ss_streaming;
 482                 uvc_streaming_std = uvc_ss_streaming;
 483                 break;
 484
 485         case USB_SPEED_HIGH:
 486                 uvc_control_desc = uvc->desc.fs_control;
 487                 uvc_streaming_cls = uvc->desc.hs_streaming;
 488                 uvc_streaming_std = uvc_hs_streaming;
 489                 break;
 490
 491         case USB_SPEED_FULL:
 492         default:
 493                 uvc_control_desc = uvc->desc.fs_control;
 494                 uvc_streaming_cls = uvc->desc.fs_streaming;
 495                 uvc_streaming_std = uvc_fs_streaming;
 496                 break;
 497         }
 498
 499         if (!uvc_control_desc || !uvc_streaming_cls)
 500                 return ERR_PTR(-ENODEV);
 501
 502         /* Descriptors layout
 503          *
 504          * uvc_iad
 505          * uvc_control_intf
 506          * Class-specific UVC control descriptors
 507          * uvc_control_ep
 508          * uvc_control_cs_ep
 509          * uvc_ss_control_comp (for SS only)
 510          * uvc_streaming_intf_alt0
 511          * Class-specific UVC streaming descriptors
 512          * uvc_{fs|hs}_streaming
 513          */
 514
 515         /* Count descriptors and compute their size. */
 516         control_size = 0;
 517         streaming_size = 0;
 518         bytes = uvc_iad.bLength + uvc_control_intf.bLength
 519               + uvc_control_ep.bLength + uvc_control_cs_ep.bLength
 520               + uvc_streaming_intf_alt0.bLength;
 521
 522         if (speed == USB_SPEED_SUPER) {
 523                 bytes += uvc_ss_control_comp.bLength;
 524                 n_desc = 6;
 525         } else {
 526                 n_desc = 5;
 527         }
 528
 529         for (src = (const struct usb_descriptor_header **)uvc_control_desc;
 530              *src; ++src) {
 531                 control_size += (*src)->bLength;
 532                 bytes += (*src)->bLength;
 533                 n_desc++;
 534         }
 535         for (src = (const struct usb_descriptor_header **)uvc_streaming_cls;
 536              *src; ++src) {
 537                 streaming_size += (*src)->bLength;
 538                 bytes += (*src)->bLength;
 539                 n_desc++;
 540         }
 541         for (src = uvc_streaming_std; *src; ++src) {
 542                 bytes += (*src)->bLength;
 543                 n_desc++;
 544         }
 545
 546         mem = kmalloc((n_desc + 1) * sizeof(*src) + bytes, GFP_KERNEL);
 547         if (mem == NULL)
 548                 return NULL;
 549
 550         hdr = mem;
 551         dst = mem;
 552         mem += (n_desc + 1) * sizeof(*src);
 553
 554         /* Copy the descriptors. */
 555         UVC_COPY_DESCRIPTOR(mem, dst, &uvc_iad);
 556         UVC_COPY_DESCRIPTOR(mem, dst, &uvc_control_intf);
 557
 558         uvc_control_header = mem;
 559         UVC_COPY_DESCRIPTORS(mem, dst,
 560                 (const struct usb_descriptor_header **)uvc_control_desc);
 561         uvc_control_header->wTotalLength = cpu_to_le16(control_size);
 562         uvc_control_header->bInCollection = 1;
 563         uvc_control_header->baInterfaceNr[0] = uvc->streaming_intf;
 564
 565         UVC_COPY_DESCRIPTOR(mem, dst, &uvc_control_ep);
 566         if (speed == USB_SPEED_SUPER)
 567                 UVC_COPY_DESCRIPTOR(mem, dst, &uvc_ss_control_comp);
 568
 569         UVC_COPY_DESCRIPTOR(mem, dst, &uvc_control_cs_ep);
 570         UVC_COPY_DESCRIPTOR(mem, dst, &uvc_streaming_intf_alt0);
 571
 572         uvc_streaming_header = mem;
 573         UVC_COPY_DESCRIPTORS(mem, dst,
 574                 (const struct usb_descriptor_header**)uvc_streaming_cls);
 575         uvc_streaming_header->wTotalLength = cpu_to_le16(streaming_size);
 576         uvc_streaming_header->bEndpointAddress = uvc->video.ep->address;
 577
 578         UVC_COPY_DESCRIPTORS(mem, dst, uvc_streaming_std);
 579
 580         *dst = NULL;
 581         return hdr;
 582 }
 583
 584 static int
 585 uvc_function_bind(struct usb_configuration *c, struct usb_function *f)
 586 {
 587         struct usb_composite_dev *cdev = c->cdev;
 588         struct uvc_device *uvc = to_uvc(f);
 589         struct usb_string *us;
 590         unsigned int max_packet_mult;
 591         unsigned int max_packet_size;
 592         struct usb_ep *ep;
 593         struct f_uvc_opts *opts;
 594         int ret = -EINVAL;
 595
 596         uvcg_info(f, "%s()\n", __func__);
 597
 598         opts = fi_to_f_uvc_opts(f->fi);
 599         /* Sanity check the streaming endpoint module parameters.
 600          */
 601         opts->streaming_interval = clamp(opts->streaming_interval, 1U, 16U);
 602         opts->streaming_maxpacket = clamp(opts->streaming_maxpacket, 1U, 3072U);
 603         opts->streaming_maxburst = min(opts->streaming_maxburst, 15U);
 604
 605         /* For SS, wMaxPacketSize has to be 1024 if bMaxBurst is not 0 */
 606         if (opts->streaming_maxburst &&
 607             (opts->streaming_maxpacket % 1024) != 0) {
 608                 opts->streaming_maxpacket = roundup(opts->streaming_maxpacket, 1024);
 609                 uvcg_info(f, "overriding streaming_maxpacket to %d\n",
 610                           opts->streaming_maxpacket);
 611         }
 612
 613         /* Fill in the FS/HS/SS Video Streaming specific descriptors from the
 614          * module parameters.
 615          *
 616          * NOTE: We assume that the user knows what they are doing and won't
 617          * give parameters that their UDC doesn't support.
 618          */
 619         if (opts->streaming_maxpacket <= 1024) {
 620                 max_packet_mult = 1;
 621                 max_packet_size = opts->streaming_maxpacket;
 622         } else if (opts->streaming_maxpacket <= 2048) {
 623                 max_packet_mult = 2;
 624                 max_packet_size = opts->streaming_maxpacket / 2;
 625         } else {
 626                 max_packet_mult = 3;
 627                 max_packet_size = opts->streaming_maxpacket / 3;
 628         }
 629
 630         uvc_fs_streaming_ep.wMaxPacketSize =
 631                 cpu_to_le16(min(opts->streaming_maxpacket, 1023U));
 632         uvc_fs_streaming_ep.bInterval = opts->streaming_interval;
 633
 634         uvc_hs_streaming_ep.wMaxPacketSize =
 635                 cpu_to_le16(max_packet_size | ((max_packet_mult - 1) << 11));
 636
 637         /* A high-bandwidth endpoint must specify a bInterval value of 1 */
 638         if (max_packet_mult > 1)
 639                 uvc_hs_streaming_ep.bInterval = 1;
 640         else
 641                 uvc_hs_streaming_ep.bInterval = opts->streaming_interval;
 642
 643         uvc_ss_streaming_ep.wMaxPacketSize = cpu_to_le16(max_packet_size);
 644         uvc_ss_streaming_ep.bInterval = opts->streaming_interval;
 645         uvc_ss_streaming_comp.bmAttributes = max_packet_mult - 1;
 646         uvc_ss_streaming_comp.bMaxBurst = opts->streaming_maxburst;
 647         uvc_ss_streaming_comp.wBytesPerInterval =
 648                 cpu_to_le16(max_packet_size * max_packet_mult *
 649                             (opts->streaming_maxburst + 1));
 650
 651         /* Allocate endpoints. */
 652         ep = usb_ep_autoconfig(cdev->gadget, &uvc_control_ep);
 653         if (!ep) {
 654                 uvcg_info(f, "Unable to allocate control EP\n");
 655                 goto error;
 656         }
 657         uvc->control_ep = ep;
 658
 659         if (gadget_is_superspeed(c->cdev->gadget))
 660                 ep = usb_ep_autoconfig_ss(cdev->gadget, &uvc_ss_streaming_ep,
 661                                           &uvc_ss_streaming_comp);
 662         else if (gadget_is_dualspeed(cdev->gadget))
 663                 ep = usb_ep_autoconfig(cdev->gadget, &uvc_hs_streaming_ep);
 664         else
 665                 ep = usb_ep_autoconfig(cdev->gadget, &uvc_fs_streaming_ep);
 666
 667         if (!ep) {
 668                 uvcg_info(f, "Unable to allocate streaming EP\n");
 669                 goto error;
 670         }
 671         uvc->video.ep = ep;
 672
 673         uvc_fs_streaming_ep.bEndpointAddress = uvc->video.ep->address;
 674         uvc_hs_streaming_ep.bEndpointAddress = uvc->video.ep->address;
 675         uvc_ss_streaming_ep.bEndpointAddress = uvc->video.ep->address;
 676
 677         us = usb_gstrings_attach(cdev, uvc_function_strings,
 678                                  ARRAY_SIZE(uvc_en_us_strings));
 679         if (IS_ERR(us)) {
 680                 ret = PTR_ERR(us);
 681                 goto error;
 682         }
 683         uvc_iad.iFunction = us[UVC_STRING_CONTROL_IDX].id;
 684         uvc_control_intf.iInterface = us[UVC_STRING_CONTROL_IDX].id;
 685         ret = us[UVC_STRING_STREAMING_IDX].id;
 686         uvc_streaming_intf_alt0.iInterface = ret;
 687         uvc_streaming_intf_alt1.iInterface = ret;
 688
 689         /* Allocate interface IDs. */
 690         if ((ret = usb_interface_id(c, f)) < 0)
 691                 goto error;
 692         uvc_iad.bFirstInterface = ret;
 693         uvc_control_intf.bInterfaceNumber = ret;
 694         uvc->control_intf = ret;
 695         opts->control_interface = ret;
 696
 697         if ((ret = usb_interface_id(c, f)) < 0)
 698                 goto error;
 699         uvc_streaming_intf_alt0.bInterfaceNumber = ret;
 700         uvc_streaming_intf_alt1.bInterfaceNumber = ret;
 701         uvc->streaming_intf = ret;
 702         opts->streaming_interface = ret;
 703
 704         /* Copy descriptors */
 705         f->fs_descriptors = uvc_copy_descriptors(uvc, USB_SPEED_FULL);
 706         if (IS_ERR(f->fs_descriptors)) {
 707                 ret = PTR_ERR(f->fs_descriptors);
 708                 f->fs_descriptors = NULL;
 709                 goto error;
 710         }
 711         if (gadget_is_dualspeed(cdev->gadget)) {
 712                 f->hs_descriptors = uvc_copy_descriptors(uvc, USB_SPEED_HIGH);
 713                 if (IS_ERR(f->hs_descriptors)) {
 714                         ret = PTR_ERR(f->hs_descriptors);
 715                         f->hs_descriptors = NULL;
 716                         goto error;
 717                 }
 718         }
 719         if (gadget_is_superspeed(c->cdev->gadget)) {
 720                 f->ss_descriptors = uvc_copy_descriptors(uvc, USB_SPEED_SUPER);
 721                 if (IS_ERR(f->ss_descriptors)) {
 722                         ret = PTR_ERR(f->ss_descriptors);
 723                         f->ss_descriptors = NULL;
 724                         goto error;
 725                 }
 726         }
 727
 728         /* Preallocate control endpoint request. */
 729         uvc->control_req = usb_ep_alloc_request(cdev->gadget->ep0, GFP_KERNEL);
 730         uvc->control_buf = kmalloc(UVC_MAX_REQUEST_SIZE, GFP_KERNEL);
 731         if (uvc->control_req == NULL || uvc->control_buf == NULL) {
 732                 ret = -ENOMEM;
 733                 goto error;
 734         }
 735
 736         uvc->control_req->buf = uvc->control_buf;
 737         uvc->control_req->complete = uvc_function_ep0_complete;
 738         uvc->control_req->context = uvc;
 739
 740         if (v4l2_device_register(&cdev->gadget->dev, &uvc->v4l2_dev)) {
 741                 uvcg_err(f, "failed to register V4L2 device\n");
 742                 goto error;
 743         }
 744
 745         /* Initialise video. */
 746         ret = uvcg_video_init(&uvc->video, uvc);
 747         if (ret < 0)
 748                 goto v4l2_error;
 749
 750         /* Register a V4L2 device. */
 751         ret = uvc_register_video(uvc);
 752         if (ret < 0) {
 753                 uvcg_err(f, "failed to register video device\n");
 754                 goto v4l2_error;
 755         }
 756
 757         return 0;
 758
 759 v4l2_error:
 760         v4l2_device_unregister(&uvc->v4l2_dev);
 761 error:
 762         if (uvc->control_req)
 763                 usb_ep_free_request(cdev->gadget->ep0, uvc->control_req);
 764         kfree(uvc->control_buf);
 765
 766         usb_free_all_descriptors(f);
 767         return ret;
 768 }
 769
 770 /* --------------------------------------------------------------------------
 771  * USB gadget function
 772  */
 773
 774 static void uvc_free_inst(struct usb_function_instance *f)
 775 {
 776         struct f_uvc_opts *opts = fi_to_f_uvc_opts(f);
 777
 778         mutex_destroy(&opts->lock);
 779         kfree(opts);
 780 }
 781
 782 static struct usb_function_instance *uvc_alloc_inst(void)
 783 {
 784         struct f_uvc_opts *opts;
 785         struct uvc_camera_terminal_descriptor *cd;
 786         struct uvc_processing_unit_descriptor *pd;
 787         struct uvc_output_terminal_descriptor *od;
 788         struct uvc_color_matching_descriptor *md;
 789         struct uvc_descriptor_header **ctl_cls;
 790         int ret;
 791
 792         opts = kzalloc(sizeof(*opts), GFP_KERNEL);
 793         if (!opts)
 794                 return ERR_PTR(-ENOMEM);
 795         opts->func_inst.free_func_inst = uvc_free_inst;
 796         mutex_init(&opts->lock);
 797
 798         cd = &opts->uvc_camera_terminal;
 799         cd->bLength                     = UVC_DT_CAMERA_TERMINAL_SIZE(3);
 800         cd->bDescriptorType             = USB_DT_CS_INTERFACE;
 801         cd->bDescriptorSubType          = UVC_VC_INPUT_TERMINAL;
 802         cd->bTerminalID                 = 1;
 803         cd->wTerminalType               = cpu_to_le16(0x0201);
 804         cd->bAssocTerminal              = 0;
 805         cd->iTerminal                   = 0;
 806         cd->wObjectiveFocalLengthMin    = cpu_to_le16(0);
 807         cd->wObjectiveFocalLengthMax    = cpu_to_le16(0);
 808         cd->wOcularFocalLength          = cpu_to_le16(0);
 809         cd->bControlSize                = 3;
 810         cd->bmControls[0]               = 2;
 811         cd->bmControls[1]               = 0;
 812         cd->bmControls[2]               = 0;
 813
 814         pd = &opts->uvc_processing;
 815         pd->bLength                     = UVC_DT_PROCESSING_UNIT_SIZE(2);
 816         pd->bDescriptorType             = USB_DT_CS_INTERFACE;
 817         pd->bDescriptorSubType          = UVC_VC_PROCESSING_UNIT;
 818         pd->bUnitID                     = 2;
 819         pd->bSourceID                   = 1;
 820         pd->wMaxMultiplier              = cpu_to_le16(16*1024);
 821         pd->bControlSize                = 2;
 822         pd->bmControls[0]               = 1;
 823         pd->bmControls[1]               = 0;
 824         pd->iProcessing                 = 0;
 825         pd->bmVideoStandards            = 0;
 826
 827         od = &opts->uvc_output_terminal;
 828         od->bLength                     = UVC_DT_OUTPUT_TERMINAL_SIZE;
 829         od->bDescriptorType             = USB_DT_CS_INTERFACE;
 830         od->bDescriptorSubType          = UVC_VC_OUTPUT_TERMINAL;
 831         od->bTerminalID                 = 3;
 832         od->wTerminalType               = cpu_to_le16(0x0101);
 833         od->bAssocTerminal              = 0;
 834         od->bSourceID                   = 2;
 835         od->iTerminal                   = 0;
 836
 837         md = &opts->uvc_color_matching;
 838         md->bLength                     = UVC_DT_COLOR_MATCHING_SIZE;
 839         md->bDescriptorType             = USB_DT_CS_INTERFACE;
 840         md->bDescriptorSubType          = UVC_VS_COLORFORMAT;
 841         md->bColorPrimaries             = 1;
 842         md->bTransferCharacteristics    = 1;
 843         md->bMatrixCoefficients         = 4;
 844
 845         /* Prepare fs control class descriptors for configfs-based gadgets */
 846         ctl_cls = opts->uvc_fs_control_cls;
 847         ctl_cls[0] = NULL;      /* assigned elsewhere by configfs */
 848         ctl_cls[1] = (struct uvc_descriptor_header *)cd;
 849         ctl_cls[2] = (struct uvc_descriptor_header *)pd;
 850         ctl_cls[3] = (struct uvc_descriptor_header *)od;
 851         ctl_cls[4] = NULL;      /* NULL-terminate */
 852         opts->fs_control =
 853                 (const struct uvc_descriptor_header * const *)ctl_cls;
 854
 855         /* Prepare hs control class descriptors for configfs-based gadgets */
 856         ctl_cls = opts->uvc_ss_control_cls;
 857         ctl_cls[0] = NULL;      /* assigned elsewhere by configfs */
 858         ctl_cls[1] = (struct uvc_descriptor_header *)cd;
 859         ctl_cls[2] = (struct uvc_descriptor_header *)pd;
 860         ctl_cls[3] = (struct uvc_descriptor_header *)od;
 861         ctl_cls[4] = NULL;      /* NULL-terminate */
 862         opts->ss_control =
 863                 (const struct uvc_descriptor_header * const *)ctl_cls;
 864
 865         opts->streaming_interval = 1;
 866         opts->streaming_maxpacket = 1024;
 867
 868         ret = uvcg_attach_configfs(opts);
 869         if (ret < 0) {
 870                 kfree(opts);
 871                 return ERR_PTR(ret);
 872         }
 873
 874         return &opts->func_inst;
 875 }
 876
 877 static void uvc_free(struct usb_function *f)
 878 {
 879         struct uvc_device *uvc = to_uvc(f);
 880         struct f_uvc_opts *opts = container_of(f->fi, struct f_uvc_opts,
 881                                                func_inst);
 882         --opts->refcnt;
 883         kfree(uvc);
 884 }
 885
 886 static void uvc_unbind(struct usb_configuration *c, struct usb_function *f)
 887 {
 888         struct usb_composite_dev *cdev = c->cdev;
 889         struct uvc_device *uvc = to_uvc(f);
 890
 891         uvcg_info(f, "%s\n", __func__);
 892
 893         device_remove_file(&uvc->vdev.dev, &dev_attr_function_name);
 894         video_unregister_device(&uvc->vdev);
 895         v4l2_device_unregister(&uvc->v4l2_dev);
 896
 897         usb_ep_free_request(cdev->gadget->ep0, uvc->control_req);
 898         kfree(uvc->control_buf);
 899
 900         usb_free_all_descriptors(f);
 901 }
 902
 903 static struct usb_function *uvc_alloc(struct usb_function_instance *fi)
 904 {
 905         struct uvc_device *uvc;
 906         struct f_uvc_opts *opts;
 907         struct uvc_descriptor_header **strm_cls;
 908
 909         uvc = kzalloc(sizeof(*uvc), GFP_KERNEL);
 910         if (uvc == NULL)
 911                 return ERR_PTR(-ENOMEM);
 912
 913         mutex_init(&uvc->video.mutex);
 914         uvc->state = UVC_STATE_DISCONNECTED;
 915         opts = fi_to_f_uvc_opts(fi);
 916
 917         mutex_lock(&opts->lock);
 918         if (opts->uvc_fs_streaming_cls) {
 919                 strm_cls = opts->uvc_fs_streaming_cls;
 920                 opts->fs_streaming =
 921                         (const struct uvc_descriptor_header * const *)strm_cls;
 922         }
 923         if (opts->uvc_hs_streaming_cls) {
 924                 strm_cls = opts->uvc_hs_streaming_cls;
 925                 opts->hs_streaming =
 926                         (const struct uvc_descriptor_header * const *)strm_cls;
 927         }
 928         if (opts->uvc_ss_streaming_cls) {
 929                 strm_cls = opts->uvc_ss_streaming_cls;
 930                 opts->ss_streaming =
 931                         (const struct uvc_descriptor_header * const *)strm_cls;
 932         }
 933
 934         uvc->desc.fs_control = opts->fs_control;
 935         uvc->desc.ss_control = opts->ss_control;
 936         uvc->desc.fs_streaming = opts->fs_streaming;
 937         uvc->desc.hs_streaming = opts->hs_streaming;
 938         uvc->desc.ss_streaming = opts->ss_streaming;
 939         ++opts->refcnt;
 940         mutex_unlock(&opts->lock);
 941
 942         /* Register the function. */
 943         uvc->func.name = "uvc";
 944         uvc->func.bind = uvc_function_bind;
 945         uvc->func.unbind = uvc_unbind;
 946         uvc->func.get_alt = uvc_function_get_alt;
 947         uvc->func.set_alt = uvc_function_set_alt;
 948         uvc->func.disable = uvc_function_disable;
 949         uvc->func.setup = uvc_function_setup;
 950         uvc->func.free_func = uvc_free;
 951         uvc->func.bind_deactivated = true;
 952
 953         return &uvc->func;
 954 }
 955
 956 DECLARE_USB_FUNCTION_INIT(uvc, uvc_alloc_inst, uvc_alloc);
 957 MODULE_LICENSE("GPL");
 958 MODULE_AUTHOR("Laurent Pinchart");