linux/drivers/usb/gadget/function/f_uvc.c
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   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
  33unsigned int uvc_gadget_trace_param;
  34module_param_named(trace, uvc_gadget_trace_param, uint, 0644);
  35MODULE_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
  46static 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
  52static struct usb_gadget_strings uvc_stringtab = {
  53        .language = 0x0409,     /* en-us */
  54        .strings = uvc_en_us_strings,
  55};
  56
  57static 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
  67static 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
  78static 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
  90static 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
  99static 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
 108static 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
 115static 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
 127static 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
 139static 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
 150static 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
 161static 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
 173static 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
 181static 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
 187static 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
 193static 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
 204static void
 205uvc_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
 222static int
 223uvc_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
 252void 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
 259static int
 260uvc_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
 274static int
 275uvc_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
 359static void
 360uvc_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
 381void
 382uvc_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
 390void
 391uvc_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
 403static 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
 411static DEVICE_ATTR_RO(function_name);
 412
 413static int
 414uvc_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.v4l2_dev->dev = &cdev->gadget->dev;
 422        uvc->vdev.fops = &uvc_v4l2_fops;
 423        uvc->vdev.ioctl_ops = &uvc_v4l2_ioctl_ops;
 424        uvc->vdev.release = video_device_release_empty;
 425        uvc->vdev.vfl_dir = VFL_DIR_TX;
 426        uvc->vdev.lock = &uvc->video.mutex;
 427        uvc->vdev.device_caps = V4L2_CAP_VIDEO_OUTPUT | V4L2_CAP_STREAMING;
 428        strlcpy(uvc->vdev.name, cdev->gadget->name, sizeof(uvc->vdev.name));
 429
 430        video_set_drvdata(&uvc->vdev, uvc);
 431
 432        ret = video_register_device(&uvc->vdev, VFL_TYPE_VIDEO, -1);
 433        if (ret < 0)
 434                return ret;
 435
 436        ret = device_create_file(&uvc->vdev.dev, &dev_attr_function_name);
 437        if (ret < 0) {
 438                video_unregister_device(&uvc->vdev);
 439                return ret;
 440        }
 441
 442        return 0;
 443}
 444
 445#define UVC_COPY_DESCRIPTOR(mem, dst, desc) \
 446        do { \
 447                memcpy(mem, desc, (desc)->bLength); \
 448                *(dst)++ = mem; \
 449                mem += (desc)->bLength; \
 450        } while (0);
 451
 452#define UVC_COPY_DESCRIPTORS(mem, dst, src) \
 453        do { \
 454                const struct usb_descriptor_header * const *__src; \
 455                for (__src = src; *__src; ++__src) { \
 456                        memcpy(mem, *__src, (*__src)->bLength); \
 457                        *dst++ = mem; \
 458                        mem += (*__src)->bLength; \
 459                } \
 460        } while (0)
 461
 462static struct usb_descriptor_header **
 463uvc_copy_descriptors(struct uvc_device *uvc, enum usb_device_speed speed)
 464{
 465        struct uvc_input_header_descriptor *uvc_streaming_header;
 466        struct uvc_header_descriptor *uvc_control_header;
 467        const struct uvc_descriptor_header * const *uvc_control_desc;
 468        const struct uvc_descriptor_header * const *uvc_streaming_cls;
 469        const struct usb_descriptor_header * const *uvc_streaming_std;
 470        const struct usb_descriptor_header * const *src;
 471        struct usb_descriptor_header **dst;
 472        struct usb_descriptor_header **hdr;
 473        unsigned int control_size;
 474        unsigned int streaming_size;
 475        unsigned int n_desc;
 476        unsigned int bytes;
 477        void *mem;
 478
 479        switch (speed) {
 480        case USB_SPEED_SUPER:
 481                uvc_control_desc = uvc->desc.ss_control;
 482                uvc_streaming_cls = uvc->desc.ss_streaming;
 483                uvc_streaming_std = uvc_ss_streaming;
 484                break;
 485
 486        case USB_SPEED_HIGH:
 487                uvc_control_desc = uvc->desc.fs_control;
 488                uvc_streaming_cls = uvc->desc.hs_streaming;
 489                uvc_streaming_std = uvc_hs_streaming;
 490                break;
 491
 492        case USB_SPEED_FULL:
 493        default:
 494                uvc_control_desc = uvc->desc.fs_control;
 495                uvc_streaming_cls = uvc->desc.fs_streaming;
 496                uvc_streaming_std = uvc_fs_streaming;
 497                break;
 498        }
 499
 500        if (!uvc_control_desc || !uvc_streaming_cls)
 501                return ERR_PTR(-ENODEV);
 502
 503        /* Descriptors layout
 504         *
 505         * uvc_iad
 506         * uvc_control_intf
 507         * Class-specific UVC control descriptors
 508         * uvc_control_ep
 509         * uvc_control_cs_ep
 510         * uvc_ss_control_comp (for SS only)
 511         * uvc_streaming_intf_alt0
 512         * Class-specific UVC streaming descriptors
 513         * uvc_{fs|hs}_streaming
 514         */
 515
 516        /* Count descriptors and compute their size. */
 517        control_size = 0;
 518        streaming_size = 0;
 519        bytes = uvc_iad.bLength + uvc_control_intf.bLength
 520              + uvc_control_ep.bLength + uvc_control_cs_ep.bLength
 521              + uvc_streaming_intf_alt0.bLength;
 522
 523        if (speed == USB_SPEED_SUPER) {
 524                bytes += uvc_ss_control_comp.bLength;
 525                n_desc = 6;
 526        } else {
 527                n_desc = 5;
 528        }
 529
 530        for (src = (const struct usb_descriptor_header **)uvc_control_desc;
 531             *src; ++src) {
 532                control_size += (*src)->bLength;
 533                bytes += (*src)->bLength;
 534                n_desc++;
 535        }
 536        for (src = (const struct usb_descriptor_header **)uvc_streaming_cls;
 537             *src; ++src) {
 538                streaming_size += (*src)->bLength;
 539                bytes += (*src)->bLength;
 540                n_desc++;
 541        }
 542        for (src = uvc_streaming_std; *src; ++src) {
 543                bytes += (*src)->bLength;
 544                n_desc++;
 545        }
 546
 547        mem = kmalloc((n_desc + 1) * sizeof(*src) + bytes, GFP_KERNEL);
 548        if (mem == NULL)
 549                return NULL;
 550
 551        hdr = mem;
 552        dst = mem;
 553        mem += (n_desc + 1) * sizeof(*src);
 554
 555        /* Copy the descriptors. */
 556        UVC_COPY_DESCRIPTOR(mem, dst, &uvc_iad);
 557        UVC_COPY_DESCRIPTOR(mem, dst, &uvc_control_intf);
 558
 559        uvc_control_header = mem;
 560        UVC_COPY_DESCRIPTORS(mem, dst,
 561                (const struct usb_descriptor_header **)uvc_control_desc);
 562        uvc_control_header->wTotalLength = cpu_to_le16(control_size);
 563        uvc_control_header->bInCollection = 1;
 564        uvc_control_header->baInterfaceNr[0] = uvc->streaming_intf;
 565
 566        UVC_COPY_DESCRIPTOR(mem, dst, &uvc_control_ep);
 567        if (speed == USB_SPEED_SUPER)
 568                UVC_COPY_DESCRIPTOR(mem, dst, &uvc_ss_control_comp);
 569
 570        UVC_COPY_DESCRIPTOR(mem, dst, &uvc_control_cs_ep);
 571        UVC_COPY_DESCRIPTOR(mem, dst, &uvc_streaming_intf_alt0);
 572
 573        uvc_streaming_header = mem;
 574        UVC_COPY_DESCRIPTORS(mem, dst,
 575                (const struct usb_descriptor_header**)uvc_streaming_cls);
 576        uvc_streaming_header->wTotalLength = cpu_to_le16(streaming_size);
 577        uvc_streaming_header->bEndpointAddress = uvc->video.ep->address;
 578
 579        UVC_COPY_DESCRIPTORS(mem, dst, uvc_streaming_std);
 580
 581        *dst = NULL;
 582        return hdr;
 583}
 584
 585static int
 586uvc_function_bind(struct usb_configuration *c, struct usb_function *f)
 587{
 588        struct usb_composite_dev *cdev = c->cdev;
 589        struct uvc_device *uvc = to_uvc(f);
 590        struct usb_string *us;
 591        unsigned int max_packet_mult;
 592        unsigned int max_packet_size;
 593        struct usb_ep *ep;
 594        struct f_uvc_opts *opts;
 595        int ret = -EINVAL;
 596
 597        uvcg_info(f, "%s()\n", __func__);
 598
 599        opts = fi_to_f_uvc_opts(f->fi);
 600        /* Sanity check the streaming endpoint module parameters.
 601         */
 602        opts->streaming_interval = clamp(opts->streaming_interval, 1U, 16U);
 603        opts->streaming_maxpacket = clamp(opts->streaming_maxpacket, 1U, 3072U);
 604        opts->streaming_maxburst = min(opts->streaming_maxburst, 15U);
 605
 606        /* For SS, wMaxPacketSize has to be 1024 if bMaxBurst is not 0 */
 607        if (opts->streaming_maxburst &&
 608            (opts->streaming_maxpacket % 1024) != 0) {
 609                opts->streaming_maxpacket = roundup(opts->streaming_maxpacket, 1024);
 610                uvcg_info(f, "overriding streaming_maxpacket to %d\n",
 611                          opts->streaming_maxpacket);
 612        }
 613
 614        /* Fill in the FS/HS/SS Video Streaming specific descriptors from the
 615         * module parameters.
 616         *
 617         * NOTE: We assume that the user knows what they are doing and won't
 618         * give parameters that their UDC doesn't support.
 619         */
 620        if (opts->streaming_maxpacket <= 1024) {
 621                max_packet_mult = 1;
 622                max_packet_size = opts->streaming_maxpacket;
 623        } else if (opts->streaming_maxpacket <= 2048) {
 624                max_packet_mult = 2;
 625                max_packet_size = opts->streaming_maxpacket / 2;
 626        } else {
 627                max_packet_mult = 3;
 628                max_packet_size = opts->streaming_maxpacket / 3;
 629        }
 630
 631        uvc_fs_streaming_ep.wMaxPacketSize =
 632                cpu_to_le16(min(opts->streaming_maxpacket, 1023U));
 633        uvc_fs_streaming_ep.bInterval = opts->streaming_interval;
 634
 635        uvc_hs_streaming_ep.wMaxPacketSize =
 636                cpu_to_le16(max_packet_size | ((max_packet_mult - 1) << 11));
 637
 638        /* A high-bandwidth endpoint must specify a bInterval value of 1 */
 639        if (max_packet_mult > 1)
 640                uvc_hs_streaming_ep.bInterval = 1;
 641        else
 642                uvc_hs_streaming_ep.bInterval = opts->streaming_interval;
 643
 644        uvc_ss_streaming_ep.wMaxPacketSize = cpu_to_le16(max_packet_size);
 645        uvc_ss_streaming_ep.bInterval = opts->streaming_interval;
 646        uvc_ss_streaming_comp.bmAttributes = max_packet_mult - 1;
 647        uvc_ss_streaming_comp.bMaxBurst = opts->streaming_maxburst;
 648        uvc_ss_streaming_comp.wBytesPerInterval =
 649                cpu_to_le16(max_packet_size * max_packet_mult *
 650                            (opts->streaming_maxburst + 1));
 651
 652        /* Allocate endpoints. */
 653        ep = usb_ep_autoconfig(cdev->gadget, &uvc_control_ep);
 654        if (!ep) {
 655                uvcg_info(f, "Unable to allocate control EP\n");
 656                goto error;
 657        }
 658        uvc->control_ep = ep;
 659
 660        if (gadget_is_superspeed(c->cdev->gadget))
 661                ep = usb_ep_autoconfig_ss(cdev->gadget, &uvc_ss_streaming_ep,
 662                                          &uvc_ss_streaming_comp);
 663        else if (gadget_is_dualspeed(cdev->gadget))
 664                ep = usb_ep_autoconfig(cdev->gadget, &uvc_hs_streaming_ep);
 665        else
 666                ep = usb_ep_autoconfig(cdev->gadget, &uvc_fs_streaming_ep);
 667
 668        if (!ep) {
 669                uvcg_info(f, "Unable to allocate streaming EP\n");
 670                goto error;
 671        }
 672        uvc->video.ep = ep;
 673
 674        uvc_fs_streaming_ep.bEndpointAddress = uvc->video.ep->address;
 675        uvc_hs_streaming_ep.bEndpointAddress = uvc->video.ep->address;
 676        uvc_ss_streaming_ep.bEndpointAddress = uvc->video.ep->address;
 677
 678        us = usb_gstrings_attach(cdev, uvc_function_strings,
 679                                 ARRAY_SIZE(uvc_en_us_strings));
 680        if (IS_ERR(us)) {
 681                ret = PTR_ERR(us);
 682                goto error;
 683        }
 684        uvc_iad.iFunction = us[UVC_STRING_CONTROL_IDX].id;
 685        uvc_control_intf.iInterface = us[UVC_STRING_CONTROL_IDX].id;
 686        ret = us[UVC_STRING_STREAMING_IDX].id;
 687        uvc_streaming_intf_alt0.iInterface = ret;
 688        uvc_streaming_intf_alt1.iInterface = ret;
 689
 690        /* Allocate interface IDs. */
 691        if ((ret = usb_interface_id(c, f)) < 0)
 692                goto error;
 693        uvc_iad.bFirstInterface = ret;
 694        uvc_control_intf.bInterfaceNumber = ret;
 695        uvc->control_intf = ret;
 696        opts->control_interface = ret;
 697
 698        if ((ret = usb_interface_id(c, f)) < 0)
 699                goto error;
 700        uvc_streaming_intf_alt0.bInterfaceNumber = ret;
 701        uvc_streaming_intf_alt1.bInterfaceNumber = ret;
 702        uvc->streaming_intf = ret;
 703        opts->streaming_interface = ret;
 704
 705        /* Copy descriptors */
 706        f->fs_descriptors = uvc_copy_descriptors(uvc, USB_SPEED_FULL);
 707        if (IS_ERR(f->fs_descriptors)) {
 708                ret = PTR_ERR(f->fs_descriptors);
 709                f->fs_descriptors = NULL;
 710                goto error;
 711        }
 712        if (gadget_is_dualspeed(cdev->gadget)) {
 713                f->hs_descriptors = uvc_copy_descriptors(uvc, USB_SPEED_HIGH);
 714                if (IS_ERR(f->hs_descriptors)) {
 715                        ret = PTR_ERR(f->hs_descriptors);
 716                        f->hs_descriptors = NULL;
 717                        goto error;
 718                }
 719        }
 720        if (gadget_is_superspeed(c->cdev->gadget)) {
 721                f->ss_descriptors = uvc_copy_descriptors(uvc, USB_SPEED_SUPER);
 722                if (IS_ERR(f->ss_descriptors)) {
 723                        ret = PTR_ERR(f->ss_descriptors);
 724                        f->ss_descriptors = NULL;
 725                        goto error;
 726                }
 727        }
 728
 729        /* Preallocate control endpoint request. */
 730        uvc->control_req = usb_ep_alloc_request(cdev->gadget->ep0, GFP_KERNEL);
 731        uvc->control_buf = kmalloc(UVC_MAX_REQUEST_SIZE, GFP_KERNEL);
 732        if (uvc->control_req == NULL || uvc->control_buf == NULL) {
 733                ret = -ENOMEM;
 734                goto error;
 735        }
 736
 737        uvc->control_req->buf = uvc->control_buf;
 738        uvc->control_req->complete = uvc_function_ep0_complete;
 739        uvc->control_req->context = uvc;
 740
 741        if (v4l2_device_register(&cdev->gadget->dev, &uvc->v4l2_dev)) {
 742                uvcg_err(f, "failed to register V4L2 device\n");
 743                goto error;
 744        }
 745
 746        /* Initialise video. */
 747        ret = uvcg_video_init(&uvc->video, uvc);
 748        if (ret < 0)
 749                goto v4l2_error;
 750
 751        /* Register a V4L2 device. */
 752        ret = uvc_register_video(uvc);
 753        if (ret < 0) {
 754                uvcg_err(f, "failed to register video device\n");
 755                goto v4l2_error;
 756        }
 757
 758        return 0;
 759
 760v4l2_error:
 761        v4l2_device_unregister(&uvc->v4l2_dev);
 762error:
 763        if (uvc->control_req)
 764                usb_ep_free_request(cdev->gadget->ep0, uvc->control_req);
 765        kfree(uvc->control_buf);
 766
 767        usb_free_all_descriptors(f);
 768        return ret;
 769}
 770
 771/* --------------------------------------------------------------------------
 772 * USB gadget function
 773 */
 774
 775static void uvc_free_inst(struct usb_function_instance *f)
 776{
 777        struct f_uvc_opts *opts = fi_to_f_uvc_opts(f);
 778
 779        mutex_destroy(&opts->lock);
 780        kfree(opts);
 781}
 782
 783static struct usb_function_instance *uvc_alloc_inst(void)
 784{
 785        struct f_uvc_opts *opts;
 786        struct uvc_camera_terminal_descriptor *cd;
 787        struct uvc_processing_unit_descriptor *pd;
 788        struct uvc_output_terminal_descriptor *od;
 789        struct uvc_color_matching_descriptor *md;
 790        struct uvc_descriptor_header **ctl_cls;
 791        int ret;
 792
 793        opts = kzalloc(sizeof(*opts), GFP_KERNEL);
 794        if (!opts)
 795                return ERR_PTR(-ENOMEM);
 796        opts->func_inst.free_func_inst = uvc_free_inst;
 797        mutex_init(&opts->lock);
 798
 799        cd = &opts->uvc_camera_terminal;
 800        cd->bLength                     = UVC_DT_CAMERA_TERMINAL_SIZE(3);
 801        cd->bDescriptorType             = USB_DT_CS_INTERFACE;
 802        cd->bDescriptorSubType          = UVC_VC_INPUT_TERMINAL;
 803        cd->bTerminalID                 = 1;
 804        cd->wTerminalType               = cpu_to_le16(0x0201);
 805        cd->bAssocTerminal              = 0;
 806        cd->iTerminal                   = 0;
 807        cd->wObjectiveFocalLengthMin    = cpu_to_le16(0);
 808        cd->wObjectiveFocalLengthMax    = cpu_to_le16(0);
 809        cd->wOcularFocalLength          = cpu_to_le16(0);
 810        cd->bControlSize                = 3;
 811        cd->bmControls[0]               = 2;
 812        cd->bmControls[1]               = 0;
 813        cd->bmControls[2]               = 0;
 814
 815        pd = &opts->uvc_processing;
 816        pd->bLength                     = UVC_DT_PROCESSING_UNIT_SIZE(2);
 817        pd->bDescriptorType             = USB_DT_CS_INTERFACE;
 818        pd->bDescriptorSubType          = UVC_VC_PROCESSING_UNIT;
 819        pd->bUnitID                     = 2;
 820        pd->bSourceID                   = 1;
 821        pd->wMaxMultiplier              = cpu_to_le16(16*1024);
 822        pd->bControlSize                = 2;
 823        pd->bmControls[0]               = 1;
 824        pd->bmControls[1]               = 0;
 825        pd->iProcessing                 = 0;
 826        pd->bmVideoStandards            = 0;
 827
 828        od = &opts->uvc_output_terminal;
 829        od->bLength                     = UVC_DT_OUTPUT_TERMINAL_SIZE;
 830        od->bDescriptorType             = USB_DT_CS_INTERFACE;
 831        od->bDescriptorSubType          = UVC_VC_OUTPUT_TERMINAL;
 832        od->bTerminalID                 = 3;
 833        od->wTerminalType               = cpu_to_le16(0x0101);
 834        od->bAssocTerminal              = 0;
 835        od->bSourceID                   = 2;
 836        od->iTerminal                   = 0;
 837
 838        md = &opts->uvc_color_matching;
 839        md->bLength                     = UVC_DT_COLOR_MATCHING_SIZE;
 840        md->bDescriptorType             = USB_DT_CS_INTERFACE;
 841        md->bDescriptorSubType          = UVC_VS_COLORFORMAT;
 842        md->bColorPrimaries             = 1;
 843        md->bTransferCharacteristics    = 1;
 844        md->bMatrixCoefficients         = 4;
 845
 846        /* Prepare fs control class descriptors for configfs-based gadgets */
 847        ctl_cls = opts->uvc_fs_control_cls;
 848        ctl_cls[0] = NULL;      /* assigned elsewhere by configfs */
 849        ctl_cls[1] = (struct uvc_descriptor_header *)cd;
 850        ctl_cls[2] = (struct uvc_descriptor_header *)pd;
 851        ctl_cls[3] = (struct uvc_descriptor_header *)od;
 852        ctl_cls[4] = NULL;      /* NULL-terminate */
 853        opts->fs_control =
 854                (const struct uvc_descriptor_header * const *)ctl_cls;
 855
 856        /* Prepare hs control class descriptors for configfs-based gadgets */
 857        ctl_cls = opts->uvc_ss_control_cls;
 858        ctl_cls[0] = NULL;      /* assigned elsewhere by configfs */
 859        ctl_cls[1] = (struct uvc_descriptor_header *)cd;
 860        ctl_cls[2] = (struct uvc_descriptor_header *)pd;
 861        ctl_cls[3] = (struct uvc_descriptor_header *)od;
 862        ctl_cls[4] = NULL;      /* NULL-terminate */
 863        opts->ss_control =
 864                (const struct uvc_descriptor_header * const *)ctl_cls;
 865
 866        opts->streaming_interval = 1;
 867        opts->streaming_maxpacket = 1024;
 868
 869        ret = uvcg_attach_configfs(opts);
 870        if (ret < 0) {
 871                kfree(opts);
 872                return ERR_PTR(ret);
 873        }
 874
 875        return &opts->func_inst;
 876}
 877
 878static void uvc_free(struct usb_function *f)
 879{
 880        struct uvc_device *uvc = to_uvc(f);
 881        struct f_uvc_opts *opts = container_of(f->fi, struct f_uvc_opts,
 882                                               func_inst);
 883        --opts->refcnt;
 884        kfree(uvc);
 885}
 886
 887static void uvc_unbind(struct usb_configuration *c, struct usb_function *f)
 888{
 889        struct usb_composite_dev *cdev = c->cdev;
 890        struct uvc_device *uvc = to_uvc(f);
 891
 892        uvcg_info(f, "%s\n", __func__);
 893
 894        device_remove_file(&uvc->vdev.dev, &dev_attr_function_name);
 895        video_unregister_device(&uvc->vdev);
 896        v4l2_device_unregister(&uvc->v4l2_dev);
 897
 898        usb_ep_free_request(cdev->gadget->ep0, uvc->control_req);
 899        kfree(uvc->control_buf);
 900
 901        usb_free_all_descriptors(f);
 902}
 903
 904static struct usb_function *uvc_alloc(struct usb_function_instance *fi)
 905{
 906        struct uvc_device *uvc;
 907        struct f_uvc_opts *opts;
 908        struct uvc_descriptor_header **strm_cls;
 909
 910        uvc = kzalloc(sizeof(*uvc), GFP_KERNEL);
 911        if (uvc == NULL)
 912                return ERR_PTR(-ENOMEM);
 913
 914        mutex_init(&uvc->video.mutex);
 915        uvc->state = UVC_STATE_DISCONNECTED;
 916        opts = fi_to_f_uvc_opts(fi);
 917
 918        mutex_lock(&opts->lock);
 919        if (opts->uvc_fs_streaming_cls) {
 920                strm_cls = opts->uvc_fs_streaming_cls;
 921                opts->fs_streaming =
 922                        (const struct uvc_descriptor_header * const *)strm_cls;
 923        }
 924        if (opts->uvc_hs_streaming_cls) {
 925                strm_cls = opts->uvc_hs_streaming_cls;
 926                opts->hs_streaming =
 927                        (const struct uvc_descriptor_header * const *)strm_cls;
 928        }
 929        if (opts->uvc_ss_streaming_cls) {
 930                strm_cls = opts->uvc_ss_streaming_cls;
 931                opts->ss_streaming =
 932                        (const struct uvc_descriptor_header * const *)strm_cls;
 933        }
 934
 935        uvc->desc.fs_control = opts->fs_control;
 936        uvc->desc.ss_control = opts->ss_control;
 937        uvc->desc.fs_streaming = opts->fs_streaming;
 938        uvc->desc.hs_streaming = opts->hs_streaming;
 939        uvc->desc.ss_streaming = opts->ss_streaming;
 940        ++opts->refcnt;
 941        mutex_unlock(&opts->lock);
 942
 943        /* Register the function. */
 944        uvc->func.name = "uvc";
 945        uvc->func.bind = uvc_function_bind;
 946        uvc->func.unbind = uvc_unbind;
 947        uvc->func.get_alt = uvc_function_get_alt;
 948        uvc->func.set_alt = uvc_function_set_alt;
 949        uvc->func.disable = uvc_function_disable;
 950        uvc->func.setup = uvc_function_setup;
 951        uvc->func.free_func = uvc_free;
 952        uvc->func.bind_deactivated = true;
 953
 954        return &uvc->func;
 955}
 956
 957DECLARE_USB_FUNCTION_INIT(uvc, uvc_alloc_inst, uvc_alloc);
 958MODULE_LICENSE("GPL");
 959MODULE_AUTHOR("Laurent Pinchart");
 960