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authorLaurent Pinchart <laurent.pinchart@ideasonboard.com>2010-06-07 11:30:53 +0200
committerLaurent Pinchart <laurent.pinchart@ideasonboard.com>2010-06-07 11:30:53 +0200
commit9fbc003442056cdf59b87e94c1d0e3814575d4b3 (patch)
tree1f01cd85b4001e0fe954572087a6417d42f57803 /uvc-gadget.c
Initial import
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Diffstat (limited to 'uvc-gadget.c')
-rw-r--r--uvc-gadget.c744
1 files changed, 744 insertions, 0 deletions
diff --git a/uvc-gadget.c b/uvc-gadget.c
new file mode 100644
index 0000000..9ef315c
--- /dev/null
+++ b/uvc-gadget.c
@@ -0,0 +1,744 @@
+/*
+ * UVC gadget test application
+ *
+ * Copyright (C) 2010 Ideas on board SPRL <laurent.pinchart@ideasonboard.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ */
+
+#include <sys/time.h>
+#include <sys/ioctl.h>
+#include <sys/mman.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/select.h>
+
+#include <unistd.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <string.h>
+#include <errno.h>
+
+#include <linux/usb/ch9.h>
+#include <linux/usb/video.h>
+#include <linux/videodev2.h>
+
+#include "../drivers/usb/gadget/uvc.h"
+
+#define clamp(val, min, max) ({ \
+ typeof(val) __val = (val); \
+ typeof(min) __min = (min); \
+ typeof(max) __max = (max); \
+ (void) (&__val == &__min); \
+ (void) (&__val == &__max); \
+ __val = __val < __min ? __min: __val; \
+ __val > __max ? __max: __val; })
+
+#define ARRAY_SIZE(a) ((sizeof(a) / sizeof(a[0])))
+
+struct uvc_device
+{
+ int fd;
+
+ struct uvc_streaming_control probe;
+ struct uvc_streaming_control commit;
+
+ int control;
+
+ unsigned int fcc;
+ unsigned int width;
+ unsigned int height;
+
+ void **mem;
+ unsigned int nbufs;
+ unsigned int bufsize;
+
+ unsigned int bulk;
+ uint8_t color;
+ unsigned int imgsize;
+ void *imgdata;
+};
+
+static struct uvc_device *
+uvc_open(const char *devname)
+{
+ struct uvc_device *dev;
+ struct v4l2_capability cap;
+ int ret;
+ int fd;
+
+ fd = open(devname, O_RDWR | O_NONBLOCK);
+ if (fd == -1) {
+ printf("v4l2 open failed: %s (%d)\n", strerror(errno), errno);
+ return NULL;
+ }
+
+ printf("open succeeded, file descriptor = %d\n", fd);
+
+ ret = ioctl(fd, VIDIOC_QUERYCAP, &cap);
+ if (ret < 0) {
+ printf("unable to query device: %s (%d)\n", strerror(errno),
+ errno);
+ close(fd);
+ return NULL;
+ }
+
+ printf("device is %s on bus %s\n", cap.card, cap.bus_info);
+
+ dev = malloc(sizeof *dev);
+ if (dev == NULL) {
+ close(fd);
+ return NULL;
+ }
+
+ memset(dev, 0, sizeof *dev);
+ dev->fd = fd;
+
+ return dev;
+}
+
+static void
+uvc_close(struct uvc_device *dev)
+{
+ close(dev->fd);
+ free(dev->imgdata);
+ free(dev->mem);
+ free(dev);
+}
+
+/* ---------------------------------------------------------------------------
+ * Video streaming
+ */
+
+static void
+uvc_video_fill_buffer(struct uvc_device *dev, struct v4l2_buffer *buf)
+{
+ unsigned int bpl;
+ unsigned int i;
+
+ switch (dev->fcc) {
+ case V4L2_PIX_FMT_YUYV:
+ /* Fill the buffer with video data. */
+ bpl = dev->width * 2;
+ for (i = 0; i < dev->height; ++i)
+ memset(dev->mem[buf->index] + i*bpl, dev->color++, bpl);
+
+ buf->bytesused = bpl * dev->height;
+ break;
+
+ case V4L2_PIX_FMT_MJPEG:
+ memcpy(dev->mem[buf->index], dev->imgdata, dev->imgsize);
+ buf->bytesused = dev->imgsize;
+ break;
+ }
+}
+
+static int
+uvc_video_process(struct uvc_device *dev)
+{
+ struct v4l2_buffer buf;
+ int ret;
+
+ memset(&buf, 0, sizeof buf);
+ buf.type = V4L2_BUF_TYPE_VIDEO_OUTPUT;
+ buf.memory = V4L2_MEMORY_MMAP;
+
+ if ((ret = ioctl(dev->fd, VIDIOC_DQBUF, &buf)) < 0) {
+ printf("Unable to dequeue buffer: %s (%d).\n", strerror(errno),
+ errno);
+ return ret;
+ }
+
+ uvc_video_fill_buffer(dev, &buf);
+
+ if ((ret = ioctl(dev->fd, VIDIOC_QBUF, &buf)) < 0) {
+ printf("Unable to requeue buffer: %s (%d).\n", strerror(errno),
+ errno);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int
+uvc_video_reqbufs(struct uvc_device *dev, int nbufs)
+{
+ struct v4l2_requestbuffers rb;
+ struct v4l2_buffer buf;
+ unsigned int i;
+ int ret;
+
+ for (i = 0; i < dev->nbufs; ++i)
+ munmap(dev->mem[i], dev->bufsize);
+
+ free(dev->mem);
+ dev->mem = 0;
+ dev->nbufs = 0;
+
+ memset(&rb, 0, sizeof rb);
+ rb.count = nbufs;
+ rb.type = V4L2_BUF_TYPE_VIDEO_OUTPUT;
+ rb.memory = V4L2_MEMORY_MMAP;
+
+ ret = ioctl(dev->fd, VIDIOC_REQBUFS, &rb);
+ if (ret < 0) {
+ printf("Unable to allocate buffers: %s (%d).\n",
+ strerror(errno), errno);
+ return ret;
+ }
+
+ printf("%u buffers allocated.\n", rb.count);
+
+ /* Map the buffers. */
+ dev->mem = malloc(rb.count * sizeof dev->mem[0]);
+
+ for (i = 0; i < rb.count; ++i) {
+ memset(&buf, 0, sizeof buf);
+ buf.index = i;
+ buf.type = V4L2_BUF_TYPE_VIDEO_OUTPUT;
+ buf.memory = V4L2_MEMORY_MMAP;
+ ret = ioctl(dev->fd, VIDIOC_QUERYBUF, &buf);
+ if (ret < 0) {
+ printf("Unable to query buffer %u: %s (%d).\n", i,
+ strerror(errno), errno);
+ return -1;
+ }
+ printf("length: %u offset: %u\n", buf.length, buf.m.offset);
+
+ dev->mem[i] = mmap(0, buf.length, PROT_READ | PROT_WRITE, MAP_SHARED, dev->fd, buf.m.offset);
+ if (dev->mem[i] == MAP_FAILED) {
+ printf("Unable to map buffer %u: %s (%d)\n", i,
+ strerror(errno), errno);
+ return -1;
+ }
+ printf("Buffer %u mapped at address %p.\n", i, dev->mem[i]);
+ }
+
+ dev->bufsize = buf.length;
+ dev->nbufs = rb.count;
+
+ return 0;
+}
+
+static int
+uvc_video_stream(struct uvc_device *dev, int enable)
+{
+ struct v4l2_buffer buf;
+ unsigned int i;
+ int type = V4L2_BUF_TYPE_VIDEO_OUTPUT;
+ int ret;
+
+ if (!enable) {
+ printf("Stopping video stream.\n");
+ ioctl(dev->fd, VIDIOC_STREAMOFF, &type);
+ return 0;
+ }
+
+ printf("Starting video stream.\n");
+
+ for (i = 0; i < dev->nbufs; ++i) {
+ memset(&buf, 0, sizeof buf);
+
+ buf.index = i;
+ buf.type = V4L2_BUF_TYPE_VIDEO_OUTPUT;
+ buf.memory = V4L2_MEMORY_MMAP;
+
+ uvc_video_fill_buffer(dev, &buf);
+
+ printf("Queueing buffer %u.\n", i);
+ if ((ret = ioctl(dev->fd, VIDIOC_QBUF, &buf)) < 0) {
+ printf("Unable to queue buffer: %s (%d).\n",
+ strerror(errno), errno);
+ break;
+ }
+ }
+
+ ioctl(dev->fd, VIDIOC_STREAMON, &type);
+ return ret;
+}
+
+static int
+uvc_video_set_format(struct uvc_device *dev)
+{
+ struct v4l2_format fmt;
+ int ret;
+
+ printf("Setting format to 0x%08x %ux%u\n",
+ dev->fcc, dev->width, dev->height);
+
+ memset(&fmt, 0, sizeof fmt);
+ fmt.type = V4L2_BUF_TYPE_VIDEO_OUTPUT;
+ fmt.fmt.pix.width = dev->width;
+ fmt.fmt.pix.height = dev->height;
+ fmt.fmt.pix.pixelformat = dev->fcc;
+ fmt.fmt.pix.field = V4L2_FIELD_NONE;
+ if (dev->fcc == V4L2_PIX_FMT_MJPEG)
+ fmt.fmt.pix.sizeimage = dev->imgsize * 1.5;
+
+ if ((ret = ioctl(dev->fd, VIDIOC_S_FMT, &fmt)) < 0)
+ printf("Unable to set format: %s (%d).\n",
+ strerror(errno), errno);
+
+ return ret;
+}
+
+static int
+uvc_video_init(struct uvc_device *dev __attribute__((__unused__)))
+{
+ return 0;
+}
+
+/* ---------------------------------------------------------------------------
+ * Request processing
+ */
+
+struct uvc_frame_info
+{
+ unsigned int width;
+ unsigned int height;
+ unsigned int intervals[8];
+};
+
+struct uvc_format_info
+{
+ unsigned int fcc;
+ const struct uvc_frame_info *frames;
+};
+
+static const struct uvc_frame_info uvc_frames_yuyv[] = {
+ { 640, 360, { 666666, 10000000, 50000000, 0 }, },
+ { 1280, 720, { 50000000, 0 }, },
+ { 0, 0, { 0, }, },
+};
+
+static const struct uvc_frame_info uvc_frames_mjpeg[] = {
+ { 640, 360, { 666666, 10000000, 50000000, 0 }, },
+ { 1280, 720, { 50000000, 0 }, },
+ { 0, 0, { 0, }, },
+};
+
+static const struct uvc_format_info uvc_formats[] = {
+ { V4L2_PIX_FMT_YUYV, uvc_frames_yuyv },
+ { V4L2_PIX_FMT_MJPEG, uvc_frames_mjpeg },
+};
+
+static void
+uvc_fill_streaming_control(struct uvc_device *dev,
+ struct uvc_streaming_control *ctrl,
+ int iframe, int iformat)
+{
+ const struct uvc_format_info *format;
+ const struct uvc_frame_info *frame;
+ unsigned int nframes;
+
+ if (iformat < 0)
+ iformat = ARRAY_SIZE(uvc_formats) + iformat;
+ if (iformat < 0 || iformat >= (int)ARRAY_SIZE(uvc_formats))
+ return;
+ format = &uvc_formats[iformat];
+
+ nframes = 0;
+ while (format->frames[nframes].width != 0)
+ ++nframes;
+
+ if (iframe < 0)
+ iframe = nframes + iframe;
+ if (iframe < 0 || iframe >= (int)nframes)
+ return;
+ frame = &format->frames[iframe];
+
+ memset(ctrl, 0, sizeof *ctrl);
+
+ ctrl->bmHint = 1;
+ ctrl->bFormatIndex = iformat + 1;
+ ctrl->bFrameIndex = iframe + 1;
+ ctrl->dwFrameInterval = frame->intervals[0];
+ switch (format->fcc) {
+ case V4L2_PIX_FMT_YUYV:
+ ctrl->dwMaxVideoFrameSize = frame->width * frame->height * 2;
+ break;
+ case V4L2_PIX_FMT_MJPEG:
+ ctrl->dwMaxVideoFrameSize = dev->imgsize;
+ break;
+ }
+ ctrl->dwMaxPayloadTransferSize = 512; /* TODO this should be filled by the driver. */
+ ctrl->bmFramingInfo = 3;
+ ctrl->bPreferedVersion = 1;
+ ctrl->bMaxVersion = 1;
+}
+
+static void
+uvc_events_process_standard(struct uvc_device *dev, struct usb_ctrlrequest *ctrl,
+ struct uvc_request_data *resp)
+{
+ printf("standard request\n");
+ (void)dev;
+ (void)ctrl;
+ (void)resp;
+}
+
+static void
+uvc_events_process_control(struct uvc_device *dev, uint8_t req, uint8_t cs,
+ struct uvc_request_data *resp)
+{
+ printf("control request (req %02x cs %02x)\n", req, cs);
+ (void)dev;
+ (void)resp;
+}
+
+static void
+uvc_events_process_streaming(struct uvc_device *dev, uint8_t req, uint8_t cs,
+ struct uvc_request_data *resp)
+{
+ struct uvc_streaming_control *ctrl;
+
+ printf("streaming request (req %02x cs %02x)\n", req, cs);
+
+ if (cs != UVC_VS_PROBE_CONTROL && cs != UVC_VS_COMMIT_CONTROL)
+ return;
+
+ ctrl = (struct uvc_streaming_control *)&resp->data;
+ resp->length = sizeof *ctrl;
+
+ switch (req) {
+ case UVC_SET_CUR:
+ dev->control = cs;
+ resp->length = 34;
+ break;
+
+ case UVC_GET_CUR:
+ if (cs == UVC_VS_PROBE_CONTROL)
+ memcpy(ctrl, &dev->probe, sizeof *ctrl);
+ else
+ memcpy(ctrl, &dev->commit, sizeof *ctrl);
+ break;
+
+ case UVC_GET_MIN:
+ case UVC_GET_MAX:
+ case UVC_GET_DEF:
+ uvc_fill_streaming_control(dev, ctrl, req == UVC_GET_MAX ? -1 : 0,
+ req == UVC_GET_MAX ? -1 : 0);
+ break;
+
+ case UVC_GET_RES:
+ memset(ctrl, 0, sizeof *ctrl);
+ break;
+
+ case UVC_GET_LEN:
+ resp->data[0] = 0x00;
+ resp->data[1] = 0x22;
+ resp->length = 2;
+ break;
+
+ case UVC_GET_INFO:
+ resp->data[0] = 0x03;
+ resp->length = 1;
+ break;
+ }
+}
+
+static void
+uvc_events_process_class(struct uvc_device *dev, struct usb_ctrlrequest *ctrl,
+ struct uvc_request_data *resp)
+{
+ if ((ctrl->bRequestType & USB_RECIP_MASK) != USB_RECIP_INTERFACE)
+ return;
+
+ switch (ctrl->wIndex & 0xff) {
+ case UVC_INTF_CONTROL:
+ uvc_events_process_control(dev, ctrl->bRequest, ctrl->wValue >> 8, resp);
+ break;
+
+ case UVC_INTF_STREAMING:
+ uvc_events_process_streaming(dev, ctrl->bRequest, ctrl->wValue >> 8, resp);
+ break;
+
+ default:
+ break;
+ }
+}
+
+static void
+uvc_events_process_setup(struct uvc_device *dev, struct usb_ctrlrequest *ctrl,
+ struct uvc_request_data *resp)
+{
+ dev->control = 0;
+
+ printf("bRequestType %02x bRequest %02x wValue %04x wIndex %04x "
+ "wLength %04x\n", ctrl->bRequestType, ctrl->bRequest,
+ ctrl->wValue, ctrl->wIndex, ctrl->wLength);
+
+ switch (ctrl->bRequestType & USB_TYPE_MASK) {
+ case USB_TYPE_STANDARD:
+ uvc_events_process_standard(dev, ctrl, resp);
+ break;
+
+ case USB_TYPE_CLASS:
+ uvc_events_process_class(dev, ctrl, resp);
+ break;
+
+ default:
+ break;
+ }
+}
+
+static void
+uvc_events_process_data(struct uvc_device *dev, struct uvc_request_data *data)
+{
+ struct uvc_streaming_control *target;
+ struct uvc_streaming_control *ctrl;
+ const struct uvc_format_info *format;
+ const struct uvc_frame_info *frame;
+ const unsigned int *interval;
+ unsigned int iformat, iframe;
+ unsigned int nframes;
+
+ switch (dev->control) {
+ case UVC_VS_PROBE_CONTROL:
+ printf("setting probe control, length = %d\n", data->length);
+ target = &dev->probe;
+ break;
+
+ case UVC_VS_COMMIT_CONTROL:
+ printf("setting commit control, length = %d\n", data->length);
+ target = &dev->commit;
+ break;
+
+ default:
+ printf("setting unknown control, length = %d\n", data->length);
+ return;
+ }
+
+ ctrl = (struct uvc_streaming_control *)&data->data;
+ iformat = clamp((unsigned int)ctrl->bFormatIndex, 1U,
+ (unsigned int)ARRAY_SIZE(uvc_formats));
+ format = &uvc_formats[iformat-1];
+
+ nframes = 0;
+ while (format->frames[nframes].width != 0)
+ ++nframes;
+
+ iframe = clamp((unsigned int)ctrl->bFrameIndex, 1U, nframes);
+ frame = &format->frames[iframe-1];
+ interval = frame->intervals;
+
+ while (interval[0] < ctrl->dwFrameInterval && interval[1])
+ ++interval;
+
+ target->bFormatIndex = iformat;
+ target->bFrameIndex = iframe;
+ switch (format->fcc) {
+ case V4L2_PIX_FMT_YUYV:
+ target->dwMaxVideoFrameSize = frame->width * frame->height * 2;
+ break;
+ case V4L2_PIX_FMT_MJPEG:
+ if (dev->imgsize == 0)
+ printf("WARNING: MJPEG requested and no image loaded.\n");
+ target->dwMaxVideoFrameSize = dev->imgsize;
+ break;
+ }
+ target->dwFrameInterval = *interval;
+
+ if (dev->control == UVC_VS_COMMIT_CONTROL) {
+ dev->fcc = format->fcc;
+ dev->width = frame->width;
+ dev->height = frame->height;
+
+ uvc_video_set_format(dev);
+ if (dev->bulk)
+ uvc_video_stream(dev, 1);
+ }
+}
+
+static void
+uvc_events_process(struct uvc_device *dev)
+{
+ struct v4l2_event v4l2_event;
+ struct uvc_event *uvc_event = (void *)&v4l2_event.u.data;
+ struct uvc_request_data resp;
+ int ret;
+
+ ret = ioctl(dev->fd, VIDIOC_DQEVENT, &v4l2_event);
+ if (ret < 0) {
+ printf("VIDIOC_DQEVENT failed: %s (%d)\n", strerror(errno),
+ errno);
+ return;
+ }
+
+ memset(&resp, 0, sizeof resp);
+ resp.length = -EL2HLT;
+
+ switch (v4l2_event.type) {
+ case UVC_EVENT_CONNECT:
+ case UVC_EVENT_DISCONNECT:
+ return;
+
+ case UVC_EVENT_SETUP:
+ uvc_events_process_setup(dev, &uvc_event->req, &resp);
+ break;
+
+ case UVC_EVENT_DATA:
+ uvc_events_process_data(dev, &uvc_event->data);
+ return;
+
+ case UVC_EVENT_STREAMON:
+ uvc_video_reqbufs(dev, 4);
+ uvc_video_stream(dev, 1);
+ break;
+
+ case UVC_EVENT_STREAMOFF:
+ uvc_video_stream(dev, 0);
+ uvc_video_reqbufs(dev, 0);
+ break;
+ }
+
+ ioctl(dev->fd, UVCIOC_SEND_RESPONSE, &resp);
+ if (ret < 0) {
+ printf("UVCIOC_S_EVENT failed: %s (%d)\n", strerror(errno),
+ errno);
+ return;
+ }
+}
+
+static void
+uvc_events_init(struct uvc_device *dev)
+{
+ struct v4l2_event_subscription sub;
+
+ uvc_fill_streaming_control(dev, &dev->probe, 0, 0);
+ uvc_fill_streaming_control(dev, &dev->commit, 0, 0);
+
+ if (dev->bulk) {
+ /* FIXME Crude hack, must be negotiated with the driver. */
+ dev->probe.dwMaxPayloadTransferSize = 16 * 1024;
+ dev->commit.dwMaxPayloadTransferSize = 16 * 1024;
+ }
+
+
+ memset(&sub, 0, sizeof sub);
+ sub.type = UVC_EVENT_SETUP;
+ ioctl(dev->fd, VIDIOC_SUBSCRIBE_EVENT, &sub);
+ sub.type = UVC_EVENT_DATA;
+ ioctl(dev->fd, VIDIOC_SUBSCRIBE_EVENT, &sub);
+ sub.type = UVC_EVENT_STREAMON;
+ ioctl(dev->fd, VIDIOC_SUBSCRIBE_EVENT, &sub);
+ sub.type = UVC_EVENT_STREAMOFF;
+ ioctl(dev->fd, VIDIOC_SUBSCRIBE_EVENT, &sub);
+}
+
+/* ---------------------------------------------------------------------------
+ * main
+ */
+
+static void image_load(struct uvc_device *dev, const char *img)
+{
+ int fd = -1;
+
+ if (img == NULL)
+ return;
+
+ fd = open(img, O_RDONLY);
+ if (fd == -1) {
+ printf("Unable to open MJPEG image '%s'\n", img);
+ return;
+ }
+
+ dev->imgsize = lseek(fd, 0, SEEK_END);
+ lseek(fd, 0, SEEK_SET);
+ dev->imgdata = malloc(dev->imgsize);
+ if (dev->imgdata == NULL) {
+ printf("Unable to allocate memory for MJPEG image\n");
+ dev->imgsize = 0;
+ return;
+ }
+
+ read(fd, dev->imgdata, dev->imgsize);
+ close(fd);
+}
+
+static void usage(const char *argv0)
+{
+ fprintf(stderr, "Usage: %s [options]\n", argv0);
+ fprintf(stderr, "Available options are\n");
+ fprintf(stderr, " -b Use bulk mode\n");
+ fprintf(stderr, " -d device Video device\n");
+ fprintf(stderr, " -h Print this help screen and exit\n");
+ fprintf(stderr, " -i image MJPEG image\n");
+}
+
+int main(int argc, char *argv[])
+{
+ char *device = "/dev/video0";
+ struct uvc_device *dev;
+ int bulk_mode = 0;
+ char *mjpeg_image = NULL;
+ fd_set fds;
+ int ret, opt;
+
+ while ((opt = getopt(argc, argv, "bd:hi:")) != -1) {
+ switch (opt) {
+ case 'b':
+ bulk_mode = 1;
+ break;
+
+ case 'd':
+ device = optarg;
+ break;
+
+ case 'h':
+ usage(argv[0]);
+ return 0;
+
+ case 'i':
+ mjpeg_image = optarg;
+ break;
+
+ default:
+ fprintf(stderr, "Invalid option '-%c'\n", opt);
+ usage(argv[0]);
+ return 1;
+ }
+ }
+
+ dev = uvc_open(device);
+ if (dev == NULL)
+ return 1;
+
+ image_load(dev, mjpeg_image);
+
+ dev->bulk = bulk_mode;
+
+ uvc_events_init(dev);
+ uvc_video_init(dev);
+
+ FD_ZERO(&fds);
+ FD_SET(dev->fd, &fds);
+
+ while (1) {
+ fd_set efds = fds;
+ fd_set wfds = fds;
+
+ ret = select(dev->fd + 1, NULL, &wfds, &efds, NULL);
+ if (FD_ISSET(dev->fd, &efds))
+ uvc_events_process(dev);
+ if (FD_ISSET(dev->fd, &wfds))
+ uvc_video_process(dev);
+ }
+
+ uvc_close(dev);
+ return 0;
+}
+