自己写的uvc驱动支持IP2977/ip2970

/* 作者: [email protected]
 * 此驱动程序是基于linux2.6.31.14内核
 * 上一篇自己写的uvc驱动程序是针对环宇飞扬6190来写的，有一些缺点，这些缺点在本次的驱动
 * 中进行了修改此uvc驱动是针对IP2977进行了支持，根据IP2977芯片厂商提供的修改手册进行了修改。
 * 此驱动程序虽然支持IP2977摄像头，但是显示效果不太好，此驱动只是针对学习使用。
 */

#include
#include
#include
#include
#include
#include
#include
#include
#include
#include

#include
#include
#include

#include "uvcvideo.h"

/* 参考 drivers/media/video/uvc */

#define MYUVC_URBS 5

/* Values for bmHeaderInfo (Video and Still Image Payload Headers, 2.4.3.3) */
#define UVC_STREAM_EOH  (1 << 7)
#define UVC_STREAM_ERR  (1 << 6)
#define UVC_STREAM_STI  (1 << 5)
#define UVC_STREAM_RES  (1 << 4)
#define UVC_STREAM_SCR  (1 << 3)
#define UVC_STREAM_PTS  (1 << 2)
#define UVC_STREAM_EOF  (1 << 1)
#define UVC_STREAM_FID  (1 << 0)


struct myuvc_streaming_control {
    __u16 bmHint;
    __u8  bFormatIndex;
    __u8  bFrameIndex;
    __u32 dwFrameInterval;
    __u16 wKeyFrameRate;
    __u16 wPFrameRate;
    __u16 wCompQuality;
    __u16 wCompWindowSize;
    __u16 wDelay;
    __u32 dwMaxVideoFrameSize;
    __u32 dwMaxPayloadTransferSize;
    __u32 dwClockFrequency;
    __u8  bmFramingInfo;
    __u8  bPreferedVersion;
    __u8  bMinVersion;
    __u8  bMaxVersion;
};



struct frame_desc {
    int width;
    int height;
};

/* 参考uvc_video_queue定义一些结构体 */
struct myuvc_buffer {
    struct v4l2_buffer buf;
    int state;
    int vma_use_count; /* 表示是否已经被mmap */
    wait_queue_head_t wait;  /* APP要读某个缓冲区,如果无数据,在此休眠 */
    struct list_head stream;
    struct list_head irq;
};

struct myuvc_queue {
    void *mem;
    int count;
    int buf_size;
    struct myuvc_buffer buffer[32];

    struct urb *urb[32];
    char *urb_buffer[32];
    dma_addr_t urb_dma[32];
    unsigned int urb_size;

    struct list_head mainqueue;   /* 供APP消费用 */
    struct list_head irqqueue;    /* 供底层驱动生产用 */
};

static struct myuvc_queue myuvc_queue;

static struct video_device *myuvc_vdev;
static struct usb_device *myuvc_udev;

static int myuvc_bEndpointAddress = 0x82;
static int myuvc_streaming_intf;
static int myuvc_control_intf;
static struct v4l2_format myuvc_format;

static struct frame_desc frames[] = {{640, 480}, {320, 240}, {160, 120}};
static int frame_idx = 1;
static int bBitsPerPixel = 0; /* lsusb -v -d 0x1e4e:  "bBitsPerPixel" */
static int uvc_version = 0x0100; /* lsusb -v -d 0x1b3b: bcdUVC */

static int ProcessingUnitID = 3;  /* lsusb -v -d 0x1b3b: PROCESSING_UNIT */

/* 以后再设置 */
static int wMaxPacketSize = 800;
static int myuvc_streaming_bAlternateSetting = 5;
static int dwMaxVideoFrameSize = 77312;

static struct myuvc_streaming_control myuvc_params;

static int last_fid = -1;

/* A2 参考 uvc_v4l2_do_ioctl */
static int myuvc_vidioc_querycap(struct file *file, void  *priv,
                    struct v4l2_capability *cap)
{
    memset(cap, 0, sizeof *cap);
    strcpy(cap->driver, "myuvc");
    strcpy(cap->card, "myuvc");
    cap->version = 1;

    cap->capabilities = V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_STREAMING;

    return 0;
}

/* A3 列举支持哪种格式
 * 参考: uvc_fmts 数组
 */
static int myuvc_vidioc_enum_fmt_vid_cap(struct file *file, void  *priv,
                    struct v4l2_fmtdesc *f)
{
    /* 人工查看描述符可知我们用的摄像头只支持1种格式 */
    if (f->index >= 1)
        return -EINVAL;

    strcpy(f->description, "MJPEG");
    f->pixelformat = V4L2_PIX_FMT_MJPEG;
    //f->flags       = ;
    f->type        = V4L2_BUF_TYPE_VIDEO_CAPTURE;

    return 0;
}

/* A4 返回当前所使用的格式 */
static int myuvc_vidioc_g_fmt_vid_cap(struct file *file, void *priv,
                    struct v4l2_format *f)
{
    memcpy(f, &myuvc_format, sizeof(myuvc_format));
    return (0);
}

/* A5 测试驱动程序是否支持某种格式, 强制设置该格式
 * 参考: uvc_v4l2_try_format
 *       myvivi_vidioc_try_fmt_vid_cap
 */
static int myuvc_vidioc_try_fmt_vid_cap(struct file *file, void *priv,
            struct v4l2_format *f)
{
    if (f->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
    {
        return -EINVAL;
    }

    if (f->fmt.pix.pixelformat != V4L2_PIX_FMT_MJPEG)
        return -EINVAL;

    /* 调整format的width, height,
     * 计算bytesperline, sizeimage
     */

    /* 人工查看描述符, 确定支持哪几种分辨率 */
    f->fmt.pix.width  = frames[frame_idx].width;
    f->fmt.pix.height = frames[frame_idx].height;

    /* 对于MJPEG数据类型来说，bBitsPerPixel是无法知道的。因此我们设为0 */
    f->fmt.pix.bytesperline =
        (f->fmt.pix.width * bBitsPerPixel) >> 3;

    /* 一帧数据最大为dwMaxVideoFrameSize=77312,是由确定带宽时确定出来的。 */
    f->fmt.pix.sizeimage = dwMaxVideoFrameSize;

    f->fmt.pix.field      = V4L2_FIELD_NONE;
    /* 由描述符bColorPrimaries  1 (BT.709,sRGB)可知 */
    f->fmt.pix.colorspace = V4L2_COLORSPACE_SRGB;
    f->fmt.pix.priv       = 0;       /* private data, depends on pixelformat */

    return 0;
}

/* A6 参考 myvivi_vidioc_s_fmt_vid_cap */
static int myuvc_vidioc_s_fmt_vid_cap(struct file *file, void *priv,
                    struct v4l2_format *f)
{
    int ret = myuvc_vidioc_try_fmt_vid_cap(file, NULL, f);
    if (ret < 0)
        return ret;

    memcpy(&myuvc_format, f, sizeof(myuvc_format));

    return 0;
}

static int myuvc_free_buffers(void)
{
    if (myuvc_queue.mem)
    {
        vfree(myuvc_queue.mem);
        memset(&myuvc_queue, 0, sizeof(myuvc_queue));
        myuvc_queue.mem = NULL;
    }
    return 0;
}

/* A7 APP调用该ioctl让驱动程序分配若干个缓存, APP将从这些缓存中读到视频数据
 * 参考: uvc_alloc_buffers
 */
static int myuvc_vidioc_reqbufs(struct file *file, void *priv,
              struct v4l2_requestbuffers *p)
{
    int nbuffers = p->count;
    int bufsize  = PAGE_ALIGN(myuvc_format.fmt.pix.sizeimage);
    unsigned int i;
    void *mem = NULL;
    int ret;

    if ((ret = myuvc_free_buffers()) < 0)
        goto done;

    /* Bail out if no buffers should be allocated. */
    if (nbuffers == 0)
        goto done;

    /* Decrement the number of buffers until allocation succeeds. */
    for (; nbuffers > 0; --nbuffers) {
        mem = vmalloc_32(nbuffers * bufsize);
        if (mem != NULL)
            break;
    }

    if (mem == NULL) {
        ret = -ENOMEM;
        goto done;
    }

    /* 这些缓存是一次性作为一个整体来分配的 */
    memset(&myuvc_queue, 0, sizeof(myuvc_queue));

    INIT_LIST_HEAD(&myuvc_queue.mainqueue);
    INIT_LIST_HEAD(&myuvc_queue.irqqueue);

    for (i = 0; i < nbuffers; ++i) {
        myuvc_queue.buffer[i].buf.index = i;
        myuvc_queue.buffer[i].buf.m.offset = i * bufsize;
        myuvc_queue.buffer[i].buf.length = myuvc_format.fmt.pix.sizeimage;
        myuvc_queue.buffer[i].buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
        myuvc_queue.buffer[i].buf.sequence = 0;
        myuvc_queue.buffer[i].buf.field = V4L2_FIELD_NONE;
        myuvc_queue.buffer[i].buf.memory = V4L2_MEMORY_MMAP;
        myuvc_queue.buffer[i].buf.flags = 0;
        myuvc_queue.buffer[i].state     = VIDEOBUF_IDLE;
        init_waitqueue_head(&myuvc_queue.buffer[i].wait);
    }

    myuvc_queue.mem = mem;
    myuvc_queue.count = nbuffers;
    myuvc_queue.buf_size = bufsize;
    ret = nbuffers;

done:
    return ret;
}

/* A8 查询缓存状态, 比如地址信息(APP可以用mmap进行映射)
 * 参考 uvc_query_buffer
 */
static int myuvc_vidioc_querybuf(struct file *file, void *priv, struct v4l2_buffer *v4l2_buf)
{
    int ret = 0;

    if (v4l2_buf->index >= myuvc_queue.count) {
        ret = -EINVAL;
        goto done;
    }

    memcpy(v4l2_buf, &myuvc_queue.buffer[v4l2_buf->index].buf, sizeof(*v4l2_buf));

    /* 更新flags */
    if (myuvc_queue.buffer[v4l2_buf->index].vma_use_count)
        v4l2_buf->flags |= V4L2_BUF_FLAG_MAPPED;


    switch (myuvc_queue.buffer[v4l2_buf->index].state) {
        case VIDEOBUF_ERROR:
        case VIDEOBUF_DONE:
            v4l2_buf->flags |= V4L2_BUF_FLAG_DONE;
            break;
        case VIDEOBUF_QUEUED:
        case VIDEOBUF_ACTIVE:
            v4l2_buf->flags |= V4L2_BUF_FLAG_QUEUED;
            break;
        case VIDEOBUF_IDLE:
        default:
            break;
    }

done:
    return ret;
}

/* A10 把缓冲区放入队列, 底层的硬件操作函数将会把数据放入这个队列的缓存
 * 参考: uvc_queue_buffer
 */
static int myuvc_vidioc_qbuf(struct file *file, void *priv, struct v4l2_buffer *v4l2_buf)
{
    struct myuvc_buffer *buf;

    /* 0. APP传入的v4l2_buf可能有问题, 要做判断 */

    if (v4l2_buf->type != V4L2_BUF_TYPE_VIDEO_CAPTURE ||
        v4l2_buf->memory != V4L2_MEMORY_MMAP) {
        return -EINVAL;
    }

    if (v4l2_buf->index >= myuvc_queue.count) {
        return -EINVAL;
    }

    buf = &myuvc_queue.buffer[v4l2_buf->index];

    if (buf->state != VIDEOBUF_IDLE) {
        return -EINVAL;
    }


    /* 1. 修改状态 */
    buf->state = VIDEOBUF_QUEUED;
    buf->buf.bytesused = 0;

    /* 2. 放入2个队列 */
    /* 队列1: 供APP使用
     * 当缓冲区没有数据时,放入mainqueue队列
     * 当缓冲区有数据时, APP从mainqueue队列中取出
     */
    list_add_tail(&buf->stream, &myuvc_queue.mainqueue);

    /* 队列2: 供产生数据的函数使用
     * 当采集到数据时,从irqqueue队列中取出第1个缓冲区,存入数据
     */
    list_add_tail(&buf->irq, &myuvc_queue.irqqueue);

    return 0;
}

static void myuvc_print_streaming_params(struct myuvc_streaming_control *ctrl)
{
    printk("video params:\n");
    printk("bmHint                   = %d\n", ctrl->bmHint);
    printk("bFormatIndex             = %d\n", ctrl->bFormatIndex);
    printk("bFrameIndex              = %d\n", ctrl->bFrameIndex);
    printk("dwFrameInterval          = %d\n", ctrl->dwFrameInterval);
    printk("wKeyFrameRate            = %d\n", ctrl->wKeyFrameRate);
    printk("wPFrameRate              = %d\n", ctrl->wPFrameRate);
    printk("wCompQuality             = %d\n", ctrl->wCompQuality);
    printk("wCompWindowSize          = %d\n", ctrl->wCompWindowSize);
    printk("wDelay                   = %d\n", ctrl->wDelay);
    printk("dwMaxVideoFrameSize      = %d\n", ctrl->dwMaxVideoFrameSize);
    printk("dwMaxPayloadTransferSize = %d\n", ctrl->dwMaxPayloadTransferSize);
    printk("dwClockFrequency         = %d\n", ctrl->dwClockFrequency);
    printk("bmFramingInfo            = %d\n", ctrl->bmFramingInfo);
    printk("bPreferedVersion         = %d\n", ctrl->bPreferedVersion);
    printk("bMinVersion              = %d\n", ctrl->bMinVersion);
    printk("bMinVersion              = %d\n", ctrl->bMinVersion);
}


/* 参考: uvc_get_video_ctrl
 (ret = uvc_get_video_ctrl(video, probe, 1, GET_CUR))
 static int uvc_get_video_ctrl(struct uvc_video_device *video,
     struct uvc_streaming_control *ctrl, int probe, __u8 query)
 */
static int myuvc_get_streaming_params(struct myuvc_streaming_control *ctrl)
{
    __u8 *data;
    __u16 size;
    int ret;
    __u8 type = USB_TYPE_CLASS | USB_RECIP_INTERFACE;
    unsigned int pipe;

    size = uvc_version >= 0x0110 ? 34 : 26;
    data = kmalloc(size, GFP_KERNEL);
    if (data == NULL)
        return -ENOMEM;

    pipe = (GET_CUR & 0x80) ? usb_rcvctrlpipe(myuvc_udev, 0)
                  : usb_sndctrlpipe(myuvc_udev, 0);
    type |= (GET_CUR & 0x80) ? USB_DIR_IN : USB_DIR_OUT;

    ret = usb_control_msg(myuvc_udev, pipe, GET_CUR, type, VS_PROBE_CONTROL << 8,
            0 << 8 | myuvc_streaming_intf, data, size, 5000);

    if (ret < 0)
        goto done;

    ctrl->bmHint = le16_to_cpup((__le16 *)&data[0]);
    ctrl->bFormatIndex = data[2];
    ctrl->bFrameIndex = data[3];
    ctrl->dwFrameInterval = le32_to_cpup((__le32 *)&data[4]);
    ctrl->wKeyFrameRate = le16_to_cpup((__le16 *)&data[8]);
    ctrl->wPFrameRate = le16_to_cpup((__le16 *)&data[10]);
    ctrl->wCompQuality = le16_to_cpup((__le16 *)&data[12]);
    ctrl->wCompWindowSize = le16_to_cpup((__le16 *)&data[14]);
    ctrl->wDelay = le16_to_cpup((__le16 *)&data[16]);
    ctrl->dwMaxVideoFrameSize = get_unaligned_le32(&data[18]);
    ctrl->dwMaxPayloadTransferSize = get_unaligned_le32(&data[22]);

    if (size == 34) {
        ctrl->dwClockFrequency = get_unaligned_le32(&data[26]);
        ctrl->bmFramingInfo = data[30];
        ctrl->bPreferedVersion = data[31];
        ctrl->bMinVersion = data[32];
        ctrl->bMaxVersion = data[33];
    } else {
        //ctrl->dwClockFrequency = video->dev->clock_frequency;
        ctrl->bmFramingInfo = 0;
        ctrl->bPreferedVersion = 0;
        ctrl->bMinVersion = 0;
        ctrl->bMaxVersion = 0;
    }

done:
    kfree(data);

    return (ret < 0) ? ret : 0;
}

/* 参考: uvc_v4l2_try_format ∕uvc_probe_video
 *       uvc_set_video_ctrl(video, probe, 1)
 */
static int myuvc_try_streaming_params(struct myuvc_streaming_control *ctrl)
{
    __u8 *data;
    __u16 size;
    int ret;
    __u8 type = USB_TYPE_CLASS | USB_RECIP_INTERFACE;
    unsigned int pipe;

    memset(ctrl, 0, sizeof *ctrl);

    ctrl->bmHint = 1;    /* dwFrameInterval */
    ctrl->bFormatIndex = 1;
    ctrl->bFrameIndex  = frame_idx + 1;
    ctrl->dwFrameInterval = 333333;


    size = uvc_version >= 0x0110 ? 34 : 26;
    data = kzalloc(size, GFP_KERNEL);
    if (data == NULL)
        return -ENOMEM;

    *(__le16 *)&data[0] = cpu_to_le16(ctrl->bmHint);
    data[2] = ctrl->bFormatIndex;
    data[3] = ctrl->bFrameIndex;
    *(__le32 *)&data[4] = cpu_to_le32(ctrl->dwFrameInterval);
    *(__le16 *)&data[8] = cpu_to_le16(ctrl->wKeyFrameRate);
    *(__le16 *)&data[10] = cpu_to_le16(ctrl->wPFrameRate);
    *(__le16 *)&data[12] = cpu_to_le16(ctrl->wCompQuality);
    *(__le16 *)&data[14] = cpu_to_le16(ctrl->wCompWindowSize);
    *(__le16 *)&data[16] = cpu_to_le16(ctrl->wDelay);
    put_unaligned_le32(ctrl->dwMaxVideoFrameSize, &data[18]);
    put_unaligned_le32(ctrl->dwMaxPayloadTransferSize, &data[22]);

    if (size == 34) {
        put_unaligned_le32(ctrl->dwClockFrequency, &data[26]);
        data[30] = ctrl->bmFramingInfo;
        data[31] = ctrl->bPreferedVersion;
        data[32] = ctrl->bMinVersion;
        data[33] = ctrl->bMaxVersion;
    }

    pipe = (SET_CUR & 0x80) ? usb_rcvctrlpipe(myuvc_udev, 0)
                  : usb_sndctrlpipe(myuvc_udev, 0);
    type |= (SET_CUR & 0x80) ? USB_DIR_IN : USB_DIR_OUT;

    ret = usb_control_msg(myuvc_udev, pipe, SET_CUR, type, VS_PROBE_CONTROL << 8,
            0 << 8 | myuvc_streaming_intf, data, size, 5000);

    kfree(data);

    return (ret < 0) ? ret : 0;

}


/* 参考: uvc_v4l2_try_format ∕uvc_probe_video
 *       uvc_set_video_ctrl(video, probe, 1)
 */
static int myuvc_set_streaming_params(struct myuvc_streaming_control *ctrl)
{
    __u8 *data;
    __u16 size;
    int ret;
    __u8 type = USB_TYPE_CLASS | USB_RECIP_INTERFACE;
    unsigned int pipe;

    size = uvc_version >= 0x0110 ? 34 : 26;
    data = kzalloc(size, GFP_KERNEL);
    if (data == NULL)
        return -ENOMEM;

    *(__le16 *)&data[0] = cpu_to_le16(ctrl->bmHint);
    data[2] = ctrl->bFormatIndex;
    data[3] = ctrl->bFrameIndex;
    *(__le32 *)&data[4] = cpu_to_le32(ctrl->dwFrameInterval);
    *(__le16 *)&data[8] = cpu_to_le16(ctrl->wKeyFrameRate);
    *(__le16 *)&data[10] = cpu_to_le16(ctrl->wPFrameRate);
    *(__le16 *)&data[12] = cpu_to_le16(ctrl->wCompQuality);
    *(__le16 *)&data[14] = cpu_to_le16(ctrl->wCompWindowSize);
    *(__le16 *)&data[16] = cpu_to_le16(ctrl->wDelay);
    put_unaligned_le32(ctrl->dwMaxVideoFrameSize, &data[18]);
    put_unaligned_le32(ctrl->dwMaxPayloadTransferSize, &data[22]);

    if (size == 34) {
        put_unaligned_le32(ctrl->dwClockFrequency, &data[26]);
        data[30] = ctrl->bmFramingInfo;
        data[31] = ctrl->bPreferedVersion;
        data[32] = ctrl->bMinVersion;
        data[33] = ctrl->bMaxVersion;
    }

    pipe = (SET_CUR & 0x80) ? usb_rcvctrlpipe(myuvc_udev, 0)
                  : usb_sndctrlpipe(myuvc_udev, 0);
    type |= (SET_CUR & 0x80) ? USB_DIR_IN : USB_DIR_OUT;

    ret = usb_control_msg(myuvc_udev, pipe, SET_CUR, type, VS_COMMIT_CONTROL << 8,
            0 << 8 | myuvc_streaming_intf, data, size, 5000);

    kfree(data);

    return (ret < 0) ? ret : 0;

}

static void myuvc_uninit_urbs(void)
{
    int i;
    for (i = 0; i < MYUVC_URBS; ++i) {
        if (myuvc_queue.urb_buffer[i])
        {
            usb_buffer_free(myuvc_udev, myuvc_queue.urb_size, myuvc_queue.urb_buffer[i], myuvc_queue.urb_dma[i]);
            myuvc_queue.urb_buffer[i] = NULL;
        }

        if (myuvc_queue.urb[i])
        {
            usb_free_urb(myuvc_queue.urb[i]);
            myuvc_queue.urb[i] = NULL;
        }
    }
}

/* 参考: uvc_video_complete / uvc_video_decode_isoc */
static void myuvc_video_complete(struct urb *urb)
{
    u8 *src;
    u8 *dest;
    int ret, i;
    int len;
    int maxlen;
    int nbytes;
    struct myuvc_buffer *buf;
    static int fid;
    static int wake_cnt = 0;

    // 要修改影像資料，必須先宣告一個特別型態的指標變數，才能正確存取記憶體中的資料
    unsigned char *point_mem;
    static unsigned char *mem_temp = NULL;

    // 初始化暫存用的記憶體位置
    static unsigned int nArrayTemp_Size = 1000;

    u8* mem;
    int data_len;

    switch (urb->status) {
    case 0:
        break;

    default:
        printk("Non-zero status (%d) in video "
            "completion handler.\n", urb->status);
        return;
    }

    /* 如果irqqueue队列不空的话，从irqqueue队列中取出第1个缓冲区，用于存放urb的数据 */
    if (!list_empty(&myuvc_queue.irqqueue))
    {
        buf = list_first_entry(&myuvc_queue.irqqueue, struct myuvc_buffer, irq);
    }
    else
    {
        /* 什么情况下会导致irqqueue队列为空呢?
         * usb设备填充数据太快，但是应用程序没能及时处理
         */
        buf = NULL;
    }

    /* 开始处理urb中的每一个小包 */
    for (i = 0; i < urb->number_of_packets; ++i) {
        if (urb->iso_frame_desc[i].status < 0) {
            //printk("USB isochronous frame "
            //  "lost (%d).\n", urb->iso_frame_desc[i].status);
            continue;
        }

        src  = urb->transfer_buffer + urb->iso_frame_desc[i].offset;


        len = urb->iso_frame_desc[i].actual_length;
        /* 判断数据是否有效 */
        /* URB数据含义:
         * data[0] : 头部长度
         * data[1] : 错误状态
         */
        if (len < 2 || src[0] < 2 || src[0] > len)
            continue;

        /* Skip payloads marked with the error bit ("error frames"). */
        if (src[1] & UVC_STREAM_ERR) {
            //printk("Dropping payload (error bit set).\n");
            continue;
        }

        /* 根据ip2970/ip2977厂家提供的修改手册，如果想要支持ip2970/ip2977就必须
         * 添加如下代码
         */
        if (myuvc_udev->descriptor.idVendor == 0x1B3B)
        {
            if ( len >= 16 ) // have data in buffer
            {
                // 資料必須從data[12]開始判斷，是因為前面的資料是封包專用
                if ( (src[12]==0xFF && src[13]==0xD8 && src[14]==0xFF) ||
                    (src[12]==0xD8 && src[13]==0xFF && src[14]==0xC4))
                {
                    if(last_fid)
                        fid &= ~UVC_STREAM_FID;
                    else
                        fid |= UVC_STREAM_FID;
                }
            }
        }
        else
        {
            fid = src[1] & UVC_STREAM_FID;
        }

        /* Store the payload FID bit and return immediately when the buffer is
         * NULL.
         */
        if (buf == NULL) {
            last_fid = fid;
            continue;
        }

        /* 根据FID判断当前帧的数据是否结束 */
        /* VIDEOBUF_ACTIVE表示正在接收数据，buf->state!= VIDEOBUF_ACTIVE, 表示"之前还未接收数据"，
         * 因此就是说即将接收数据
        */
        if (buf->state != VIDEOBUF_ACTIVE) {
            if (fid == last_fid) {
                /* 既然你刚开始接收数据, 那么FID应该是一个新的值,不应该等于原来的last_fid */
                continue;
            }

            /* 表示开始接收第1个数据 */
            buf->state = VIDEOBUF_ACTIVE;
        }

        /* fid表示当前的fid。
         * fid != last_fid 表示开始新一帧了，当前的buffer已经被填充完了。
         * 这个地方是从fid来判断是否一帧数据已经结束，下面还有从数据是否填充不下了来
         * 强制认为一帧数据已经结束
         */
        if (fid != last_fid && buf->buf.bytesused != 0) {
            buf->state = VIDEOBUF_DONE;

            /* 从队列中删除, 唤醒进程 */
            list_del(&buf->irq);
            wake_up(&buf->wait);

            mem = myuvc_queue.mem + buf->buf.m.offset;
            data_len = buf->buf.bytesused;
            //printk("wake_up %d : %s %d, start data: %02x %02x, end data: %02x %02x", wake_cnt++, __FUNCTION__, __LINE__, mem[0], mem[1], mem[data_len - 2], mem[data_len - 1]);

            /* 取出下一个buf */
            if (!list_empty(&myuvc_queue.irqqueue))
            {
                buf = list_first_entry(&myuvc_queue.irqqueue, struct myuvc_buffer, irq);
            }
            else
            {
                buf = NULL;
            }
            continue;
        }
        last_fid = fid;

        dest = myuvc_queue.mem + buf->buf.m.offset + buf->buf.bytesused;

        /* 除去头部后的数据长度 */
        len -= src[0];

        /* 缓冲区最多还能存多少数据 */
        maxlen = buf->buf.length - buf->buf.bytesused;
        nbytes = min(len, maxlen);

        /* 复制数据 */
        memcpy(dest, src + src[0], nbytes);
        buf->buf.bytesused += nbytes;

        /* ip2970/ip2977 */
        if (myuvc_udev->descriptor.idVendor == 0x1B3B)
        {
            if(mem_temp == NULL) {
                mem_temp = kmalloc(nArrayTemp_Size, GFP_KERNEL);
            }
            else if(nArrayTemp_Size <= nbytes){ // 當收到的資料長度大於上一次的資料長度，則重新分配所需的空間+
                kfree(mem_temp);
                nArrayTemp_Size += 500;
                mem_temp = kmalloc(nArrayTemp_Size, GFP_KERNEL);
            }
            memset(mem_temp, 0x00, nArrayTemp_Size);

            // 指向資料儲存的記憶體位置
            point_mem = (unsigned char *)dest;
            if( *(point_mem) == 0xD8 && *(point_mem + 1) == 0xFF && *(point_mem + 2) == 0xC4){
                memcpy( mem_temp + 1, point_mem, nbytes);
                mem_temp[0] = 0xFF;
                memcpy(point_mem, mem_temp, nbytes + 1);
            }
        }



        /* 判断一帧数据是否已经全部接收到
         * 如果数据已经满了，就强制认为已经结束了
         */
        if (len > maxlen) {
            buf->state = VIDEOBUF_DONE;
        }

        /* Mark the buffer as done if the EOF marker is set. */
        if (src[1] & UVC_STREAM_EOF && buf->buf.bytesused != 0) {
           // printk("Frame complete (EOF found).\n");
            //if (len == 0)
           //     printk("EOF in empty payload.\n");
            buf->state = VIDEOBUF_DONE;
        }

        /* 当接收完一帧数据,
         * 从irqqueue中删除这个缓冲区
         * 唤醒等待数据的进程
         */
        if (buf->state == VIDEOBUF_DONE ||
            buf->state == VIDEOBUF_ERROR)
        {
            list_del(&buf->irq);
            wake_up(&buf->wait);

            mem = myuvc_queue.mem + buf->buf.m.offset;
            data_len = buf->buf.bytesused;
            //printk("wake_up %d : %s %d, start data: %02x %02x, end data: %02x %02x", wake_cnt++, __FUNCTION__, __LINE__, mem[0], mem[1], mem[data_len - 2], mem[data_len - 1]);

            /* 取出下一个buf */
            if (!list_empty(&myuvc_queue.irqqueue))
            {
                buf = list_first_entry(&myuvc_queue.irqqueue, struct myuvc_buffer, irq);
            }
            else
            {
                buf = NULL;
            }
        }

    }


    /* 再次提交URB */
    if ((ret = usb_submit_urb(urb, GFP_ATOMIC)) < 0) {
        printk("Failed to resubmit video URB (%d).\n", ret);
    }
}

/* 参考: uvc_init_video_isoc */
static int myuvc_alloc_init_urbs(void)
{
    u16 psize;
    u32 size;
    int npackets;
    int i;
    int j;

    struct urb *urb;

    psize = wMaxPacketSize; /* 实时传输端点一次能传输的最大字节数 */
    size  = myuvc_params.dwMaxVideoFrameSize;  /* 一帧数据的最大长度 */
    npackets = DIV_ROUND_UP(size, psize);
    if (npackets > 32)
        npackets = 32;

    size = myuvc_queue.urb_size = psize * npackets;

    for (i = 0; i < MYUVC_URBS; ++i) {
        /* 1. 分配usb_buffers */

        myuvc_queue.urb_buffer[i] = usb_buffer_alloc(
            myuvc_udev, size,
            GFP_KERNEL | __GFP_NOWARN, &myuvc_queue.urb_dma[i]);

        /* 2. 分配urb */
        myuvc_queue.urb[i] = usb_alloc_urb(npackets, GFP_KERNEL);

        if (!myuvc_queue.urb_buffer[i] || !myuvc_queue.urb[i])
        {
            myuvc_uninit_urbs();
            return -ENOMEM;
        }

    }


    /* 3. 设置urb */
    for (i = 0; i < MYUVC_URBS; ++i) {
        urb = myuvc_queue.urb[i];

        urb->dev = myuvc_udev;
        urb->context = NULL;
        urb->pipe = usb_rcvisocpipe(myuvc_udev,myuvc_bEndpointAddress);
        urb->transfer_flags = URB_ISO_ASAP | URB_NO_TRANSFER_DMA_MAP;
        urb->interval = 1;
        urb->transfer_buffer = myuvc_queue.urb_buffer[i];
        urb->transfer_dma = myuvc_queue.urb_dma[i];
        urb->complete = myuvc_video_complete;
        urb->number_of_packets = npackets;
        urb->transfer_buffer_length = size;

        for (j = 0; j < npackets; ++j) {
            urb->iso_frame_desc[j].offset = j * psize;
            urb->iso_frame_desc[j].length = psize;
        }

    }

    return 0;
}

/* A11 启动传输
 * 参考: uvc_video_enable(video, 1):
 *           uvc_commit_video
 *           uvc_init_video
 */
static int myuvc_vidioc_streamon(struct file *file, void *priv, enum v4l2_buf_type i)
{
    int ret;

    /* 1. 向USB摄像头设置参数: 比如使用哪个format, 使用这个format下的哪个frame(分辨率)
     * 参考: uvc_set_video_ctrl / uvc_get_video_ctrl
     * 1.1 根据一个结构体uvc_streaming_control设置数据包: 可以手工设置,也可以读出后再修改
     * 1.2 调用usb_control_msg发出数据包
     */

    /* a. 测试参数 */
    ret = myuvc_try_streaming_params(&myuvc_params);
    printk("myuvc_try_streaming_params ret = %d\n", ret);

    /* b. 取出参数 */
    ret = myuvc_get_streaming_params(&myuvc_params);
    printk("myuvc_get_streaming_params ret = %d\n", ret);

    /* c. 设置参数 */
    ret = myuvc_set_streaming_params(&myuvc_params);
    printk("myuvc_set_streaming_params ret = %d\n", ret);

    myuvc_print_streaming_params(&myuvc_params);

    /* d. 设置VideoStreaming Interface所使用的setting
     * d.1 从myuvc_params确定带宽
     * d.2 根据setting的endpoint能传输的wMaxPacketSize
     *     找到能满足该带宽的setting
     */
    /* 手工确定:
     * bandwidth = myuvc_params.dwMaxPayloadTransferSize = 800
     * 观察lsusb -v -d 0x1e4e:的结果:
     *                wMaxPacketSize     0x0320  1x 800 bytes
     * bAlternateSetting       5
     */
    usb_set_interface(myuvc_udev, myuvc_streaming_intf, myuvc_streaming_bAlternateSetting);

    /* 2. 分配设置URB */
    ret = myuvc_alloc_init_urbs();
    if (ret)
        printk("myuvc_alloc_init_urbs err : ret = %d\n", ret);

    /* 3. 提交URB以接收数据 */
    for (i = 0; i < MYUVC_URBS; ++i) {
        if ((ret = usb_submit_urb(myuvc_queue.urb[i], GFP_KERNEL)) < 0) {
            printk("Failed to submit URB %u (%d).\n", i, ret);
            myuvc_uninit_urbs();
            return ret;
        }
    }

    return 0;
}

/* A13 APP通过poll/select确定有数据后, 把缓存从队列中取出来
 * 参考: uvc_dequeue_buffer
 */
static int myuvc_vidioc_dqbuf(struct file *file, void *priv, struct v4l2_buffer *v4l2_buf)
{
    /* APP发现数据就绪后, 从mainqueue里取出这个buffer */

    struct myuvc_buffer *buf;
    int ret = 0;

    if (list_empty(&myuvc_queue.mainqueue)) {
        ret = -EINVAL;
        goto done;
    }

    buf = list_first_entry(&myuvc_queue.mainqueue, struct myuvc_buffer, stream);

    switch (buf->state) {
    case VIDEOBUF_ERROR:
        ret = -EIO;
    case VIDEOBUF_DONE:
        buf->state = VIDEOBUF_IDLE;
        break;

    case VIDEOBUF_IDLE:
    case VIDEOBUF_QUEUED:
    case VIDEOBUF_ACTIVE:
    default:
        ret = -EINVAL;
        goto done;
    }

    list_del(&buf->stream);
    memcpy(v4l2_buf, &buf->buf, sizeof *v4l2_buf);

done:
    return ret;
}

/*
 * A14 之前已经通过mmap映射了缓存, APP可以直接读数据
 * A15 再次调用myuvc_vidioc_qbuf把缓存放入队列
 * A16 poll...
 */

/* A17 停止
 * 参考 : uvc_video_enable(video, 0)
 */
static int myuvc_vidioc_streamoff(struct file *file, void *priv, enum v4l2_buf_type t)
{
    struct urb *urb;
    unsigned int i;

    /* 1. kill URB */
    for (i = 0; i < MYUVC_URBS; ++i) {
        if ((urb = myuvc_queue.urb[i]) == NULL)
            continue;
        usb_kill_urb(urb);
    }

    /* 2. free URB */
    myuvc_uninit_urbs();

    /* 3. 设置VideoStreaming Interface为setting 0 */
    usb_set_interface(myuvc_udev, myuvc_streaming_intf, 0);

    return 0;
}

    /* Control handling */


/* Extract the bit string specified by mapping->offset and mapping->size
 * from the little-endian data stored at 'data' and return the result as
 * a signed 32bit integer. Sign extension will be performed if the mapping
 * references a signed data type.
 */
static __s32 myuvc_get_le_value(const __u8 *data)
{
    int bits = 16;
    int offset = 0;
    __s32 value = 0;
    __u8 mask;

    data += offset / 8;
    offset &= 7;
    mask = ((1LL << bits) - 1) << offset;

    for (; bits > 0; data++) {
        __u8 byte = *data & mask;
        value |= offset > 0 ? (byte >> offset) : (byte << (-offset));
        bits -= 8 - (offset > 0 ? offset : 0);
        offset -= 8;
        mask = (1 << bits) - 1;
    }

    /* Sign-extend the value if needed. */
    value |= -(value & (1 << (16 - 1)));

    return value;
}

/* Set the bit string specified by mapping->offset and mapping->size
 * in the little-endian data stored at 'data' to the value 'value'.
 */
static void myuvc_set_le_value(__s32 value, __u8 *data)
{
    int bits = 16;
    int offset = 0;
    __u8 mask;

    data += offset / 8;
    offset &= 7;

    for (; bits > 0; data++) {
        mask = ((1LL << bits) - 1) << offset;
        *data = (*data & ~mask) | ((value << offset) & mask);
        value >>= offset ? offset : 8;
        bits -= 8 - offset;
        offset = 0;
    }
}



/* 参考:uvc_query_v4l2_ctrl */
int myuvc_vidioc_queryctrl (struct file *file, void *fh,
                struct v4l2_queryctrl *ctrl)
{
    __u8 type = USB_TYPE_CLASS | USB_RECIP_INTERFACE;
    unsigned int pipe;
    int ret;
    u8 data[2];

    if (ctrl->id != V4L2_CID_BRIGHTNESS)
        return -EINVAL;

    memset(ctrl, 0, sizeof *ctrl);
    ctrl->id   = V4L2_CID_BRIGHTNESS;
    ctrl->type = V4L2_CTRL_TYPE_INTEGER;
    strcpy(ctrl->name, "MyUVC_BRIGHTNESS");
    ctrl->flags = 0;

    pipe = usb_rcvctrlpipe(myuvc_udev, 0);
    type |= USB_DIR_IN;

    /* 发起USB传输确定这些值 */
    ret = usb_control_msg(myuvc_udev, pipe, GET_MIN, type, PU_BRIGHTNESS_CONTROL << 8,
            ProcessingUnitID << 8 | myuvc_control_intf, data, 2, 5000);
    if (ret != 2)
        return -EIO;
    ctrl->minimum = myuvc_get_le_value(data);    /* Note signedness */


    ret = usb_control_msg(myuvc_udev, pipe, GET_MAX, type,  PU_BRIGHTNESS_CONTROL << 8,
            ProcessingUnitID << 8 | myuvc_control_intf, data, 2, 5000);
    if (ret != 2)
        return -EIO;
    ctrl->maximum = myuvc_get_le_value(data);    /* Note signedness */

    ret = usb_control_msg(myuvc_udev, pipe, GET_RES, type, PU_BRIGHTNESS_CONTROL << 8,
             ProcessingUnitID << 8 | myuvc_control_intf, data, 2, 5000);
    if (ret != 2)
        return -EIO;
    ctrl->step = myuvc_get_le_value(data);   /* Note signedness */

    ret = usb_control_msg(myuvc_udev, pipe, GET_DEF, type, PU_BRIGHTNESS_CONTROL << 8,
            ProcessingUnitID << 8 | myuvc_control_intf, data, 2, 5000);
    if (ret != 2)
        return -EIO;
    ctrl->default_value = myuvc_get_le_value(data);  /* Note signedness */

    printk("Brightness: min =%d, max = %d, step = %d, default = %d\n", ctrl->minimum, ctrl->maximum, ctrl->step, ctrl->default_value);

    return 0;
}

/* 参考 : uvc_ctrl_get */
int myuvc_vidioc_g_ctrl (struct file *file, void *fh,
                struct v4l2_control *ctrl)
{
    __u8 type = USB_TYPE_CLASS | USB_RECIP_INTERFACE;
    unsigned int pipe;
    int ret;
    u8 data[2];

    if (ctrl->id != V4L2_CID_BRIGHTNESS)
        return -EINVAL;

    pipe = usb_rcvctrlpipe(myuvc_udev, 0);
    type |= USB_DIR_IN;

    ret = usb_control_msg(myuvc_udev, pipe, GET_CUR, type, PU_BRIGHTNESS_CONTROL << 8,
            ProcessingUnitID << 8 | myuvc_control_intf, data, 2, 5000);
    if (ret != 2)
        return -EIO;
    ctrl->value = myuvc_get_le_value(data);  /* Note signedness */

    return 0;
}

/* 参考: uvc_ctrl_set/uvc_ctrl_commit */
int myuvc_vidioc_s_ctrl (struct file *file, void *fh,
                struct v4l2_control *ctrl)
{
    __u8 type = USB_TYPE_CLASS | USB_RECIP_INTERFACE;
    unsigned int pipe;
    int ret;
    u8 data[2];

    if (ctrl->id != V4L2_CID_BRIGHTNESS)
        return -EINVAL;

    myuvc_set_le_value(ctrl->value, data);

    pipe = usb_sndctrlpipe(myuvc_udev, 0);
    type |= USB_DIR_OUT;

    ret = usb_control_msg(myuvc_udev, pipe, SET_CUR, type, PU_BRIGHTNESS_CONTROL << 8,
            ProcessingUnitID  << 8 | myuvc_control_intf, data, 2, 5000);
    if (ret != 2)
        return -EIO;

    return 0;
}



static const struct v4l2_ioctl_ops myuvc_ioctl_ops = {
        // 表示它是一个摄像头设备
        .vidioc_querycap      = myuvc_vidioc_querycap,

        /* 用于列举、获得、测试、设置摄像头的数据的格式 */
        .vidioc_enum_fmt_vid_cap  = myuvc_vidioc_enum_fmt_vid_cap,
        .vidioc_g_fmt_vid_cap     = myuvc_vidioc_g_fmt_vid_cap,
        .vidioc_try_fmt_vid_cap   = myuvc_vidioc_try_fmt_vid_cap,
        .vidioc_s_fmt_vid_cap     = myuvc_vidioc_s_fmt_vid_cap,

        /* 缓冲区操作: 申请/查询/放入队列/取出队列 */
        .vidioc_reqbufs       = myuvc_vidioc_reqbufs,
        .vidioc_querybuf      = myuvc_vidioc_querybuf,
        .vidioc_qbuf          = myuvc_vidioc_qbuf,
        .vidioc_dqbuf         = myuvc_vidioc_dqbuf,

        /* 查询/获得/设置属性 */
        .vidioc_queryctrl     = myuvc_vidioc_queryctrl,
        .vidioc_g_ctrl        = myuvc_vidioc_g_ctrl,
        .vidioc_s_ctrl        = myuvc_vidioc_s_ctrl,

        // 启动/停止
        .vidioc_streamon      = myuvc_vidioc_streamon,
        .vidioc_streamoff     = myuvc_vidioc_streamoff,
};

/* A1 */
static int myuvc_open(struct file *file)
{
    return 0;
}

static void myuvc_vm_open(struct vm_area_struct *vma)
{
    struct myuvc_buffer *buffer = vma->vm_private_data;
    buffer->vma_use_count++;
}

static void myuvc_vm_close(struct vm_area_struct *vma)
{
    struct myuvc_buffer *buffer = vma->vm_private_data;
    buffer->vma_use_count--;
}

static struct vm_operations_struct myuvc_vm_ops = {
    .open       = myuvc_vm_open,
    .close      = myuvc_vm_close,
};


/* A9 把缓存映射到APP的空间,以后APP就可以直接操作这块缓存
 * 参考: uvc_v4l2_mmap
 */
static int myuvc_mmap(struct file *file, struct vm_area_struct *vma)
{
    struct myuvc_buffer *buffer;
    struct page *page;
    unsigned long addr, start, size;
    unsigned int i;
    int ret = 0;

    start = vma->vm_start;
    size = vma->vm_end - vma->vm_start;

    /* 应用程序调用mmap函数时, 会传入offset参数
     * 根据这个offset找出指定的缓冲区
     */
    for (i = 0; i < myuvc_queue.count; ++i) {
        buffer = &myuvc_queue.buffer[i];
        if ((buffer->buf.m.offset >> PAGE_SHIFT) == vma->vm_pgoff)
            break;
    }

    if (i == myuvc_queue.count || size != myuvc_queue.buf_size) {
        ret = -EINVAL;
        goto done;
    }

    /*
     * VM_IO marks the area as being an mmaped region for I/O to a
     * device. It also prevents the region from being core dumped.
     */
    vma->vm_flags |= VM_IO;

    /* 根据虚拟地址找到缓冲区对应的page构体 */
    addr = (unsigned long)myuvc_queue.mem + buffer->buf.m.offset;
    while (size > 0) {
        page = vmalloc_to_page((void *)addr);

        /* 把page和APP传入的虚拟地址挂构 */
        if ((ret = vm_insert_page(vma, start, page)) < 0)
            goto done;

        start += PAGE_SIZE;
        addr += PAGE_SIZE;
        size -= PAGE_SIZE;
    }

    vma->vm_ops = &myuvc_vm_ops;
    vma->vm_private_data = buffer;
    myuvc_vm_open(vma);

done:
    return ret;
}

/* A12 APP调用POLL/select来确定缓存是否就绪(有数据)
 * 参考 : uvc_v4l2_poll
 */
static unsigned int myuvc_poll(struct file *file, struct poll_table_struct *wait)
{
    struct myuvc_buffer *buf;
    unsigned int mask = 0;

    /* 从mainqueuq中取出第1个缓冲区 */

    /*判断它的状态, 如果未就绪, 休眠 */

    if (list_empty(&myuvc_queue.mainqueue)) {
        mask |= POLLERR;
        goto done;
    }

    buf = list_first_entry(&myuvc_queue.mainqueue, struct myuvc_buffer, stream);

    poll_wait(file, &buf->wait, wait);
    if (buf->state == VIDEOBUF_DONE ||
        buf->state == VIDEOBUF_ERROR)
        mask |= POLLIN | POLLRDNORM;

done:
    return mask;
}

/* A18 关闭 */
static int myuvc_vidioc_streamoff(struct file *file, void *priv, enum v4l2_buf_type t);
static int myuvc_close(struct file *file)
{
    myuvc_vidioc_streamoff(NULL, NULL, 0);
    return 0;
}

static const struct v4l2_file_operations myuvc_fops = {
    .owner      = THIS_MODULE,
    .open       = myuvc_open,
    .release    = myuvc_close,
    .mmap       = myuvc_mmap,
    .ioctl      = video_ioctl2, /* V4L2 ioctl handler */
    .poll       = myuvc_poll,
};

static void myuvc_release(struct video_device *vdev)
{
}


static int myuvc_probe(struct usb_interface *intf,
             const struct usb_device_id *id)
{
    static int cnt = 0;
    struct usb_device *dev = interface_to_usbdev(intf);
    int ret;

    myuvc_udev = dev;

    printk("myuvc_probe : cnt = %d\n", cnt++);

    if (cnt == 1)
    {
        myuvc_control_intf = intf->cur_altsetting->desc.bInterfaceNumber;
    }
    else if (cnt == 2)
    {
        myuvc_streaming_intf = intf->cur_altsetting->desc.bInterfaceNumber;
    }

    if (cnt == 2)
    {
        /* 1. 分配一个video_device结构体 */
        myuvc_vdev = video_device_alloc();

        /* 2. 设置 */
        /* 2.1 */
        myuvc_vdev->release = myuvc_release;

        /* 2.2 */
        myuvc_vdev->fops    = &myuvc_fops;

        /* 2.3 */
        myuvc_vdev->ioctl_ops = &myuvc_ioctl_ops;

        /* 3. 注册 */
        video_register_device(myuvc_vdev, VFL_TYPE_GRABBER, -1);

        /* 为了确定带宽,使用哪一个setting */
        /* a. 测试参数 */
        ret = myuvc_try_streaming_params(&myuvc_params);
        printk("myuvc_try_streaming_params ret = %d\n", ret);

        /* b. 取出参数 */
        ret = myuvc_get_streaming_params(&myuvc_params);
        printk("myuvc_get_streaming_params ret = %d\n", ret);

        /* c. 设置参数 */
        ret = myuvc_set_streaming_params(&myuvc_params);
        printk("myuvc_set_streaming_params ret = %d\n", ret);

        myuvc_print_streaming_params(&myuvc_params);

    }


    return 0;
}

static void myuvc_disconnect(struct usb_interface *intf)
{
    static int cnt = 0;
    printk("myuvc_disconnect : cnt = %d\n", cnt++);

    if (cnt == 2)
    {
        video_unregister_device(myuvc_vdev);
        video_device_release(myuvc_vdev);
    }

}

static struct usb_device_id myuvc_ids[] = {
    /* Generic USB Video Class */
    { USB_INTERFACE_INFO(USB_CLASS_VIDEO, 1, 0) },  /* VideoControl Interface */
    { USB_INTERFACE_INFO(USB_CLASS_VIDEO, 2, 0) },  /* VideoStreaming Interface */
    {}
};

/* 1. 分配usb_driver */
/* 2. 设置 */
static struct usb_driver myuvc_driver = {
    .name       = "myuvc",
    .probe      = myuvc_probe,
    .disconnect = myuvc_disconnect,
    .id_table   = myuvc_ids,
};

static int myuvc_init(void)
{
    /* 3. 注册 */
    usb_register(&myuvc_driver);
    return 0;
}

static void myuvc_exit(void)
{
    usb_deregister(&myuvc_driver);
}

module_init(myuvc_init);
module_exit(myuvc_exit);

MODULE_LICENSE("GPL");