[media] usbtv: Add driver for Fushicai USBTV007 video frame grabber

Reverse-engineered driver for cheapo video digitizer, made from observations of
Windows XP driver. The protocol is not yet completely understood, so far we
don't provide any controls, only support a single format out of three and don't
support the audio device.

Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

3 files changed, 707 insertions, 0 deletions

diff --git a/drivers/media/usb/usbtv/Kconfig b/drivers/media/usb/usbtv/Kconfig
new file mode 100644
index 000000000000..8864436464bf
--- /dev/null
+++ b/drivers/media/usb/usbtv/Kconfig
@@ -0,0 +1,10 @@
+config VIDEO_USBTV
+        tristate "USBTV007 video capture support"
+        depends on VIDEO_DEV
+        select VIDEOBUF2_VMALLOC
+
+        ---help---
+          This is a video4linux2 driver for USBTV007 based video capture devices.
+
+          To compile this driver as a module, choose M here: the
+          module will be called usbtv
diff --git a/drivers/media/usb/usbtv/Makefile b/drivers/media/usb/usbtv/Makefile
new file mode 100644
index 000000000000..28b872fa94e1
--- /dev/null
+++ b/drivers/media/usb/usbtv/Makefile
@@ -0,0 +1 @@
+obj-$(CONFIG_VIDEO_USBTV) += usbtv.o
diff --git a/drivers/media/usb/usbtv/usbtv.c b/drivers/media/usb/usbtv/usbtv.c
new file mode 100644
index 000000000000..bf43f874685e
--- /dev/null
+++ b/drivers/media/usb/usbtv/usbtv.c
@@ -0,0 +1,696 @@
+/*
+ * Fushicai USBTV007 Video Grabber Driver
+ *
+ * Product web site:
+ * http://www.fushicai.com/products_detail/&productId=d05449ee-b690-42f9-a661-aa7353894bed.html
+ *
+ * Following LWN articles were very useful in construction of this driver:
+ * Video4Linux2 API series: http://lwn.net/Articles/203924/
+ * videobuf2 API explanation: http://lwn.net/Articles/447435/
+ * Thanks go to Jonathan Corbet for providing this quality documentation.
+ * He is awesome.
+ *
+ * Copyright (c) 2013 Lubomir Rintel
+ * All rights reserved.
+ * No physical hardware was harmed running Windows during the
+ * reverse-engineering activity
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions, and the following disclaimer,
+ *    without modification.
+ * 2. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * Alternatively, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL").
+ */
+
+#include <linux/init.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/usb.h>
+#include <linux/version.h>
+#include <linux/videodev2.h>
+
+#include <media/v4l2-device.h>
+#include <media/v4l2-ioctl.h>
+#include <media/videobuf2-core.h>
+#include <media/videobuf2-vmalloc.h>
+
+/* Hardware. */
+#define USBTV_VIDEO_ENDP        0x81
+#define USBTV_BASE              0xc000
+#define USBTV_REQUEST_REG       12
+
+/* Number of concurrent isochronous urbs submitted.
+ * Higher numbers was seen to overly saturate the USB bus. */
+#define USBTV_ISOC_TRANSFERS    16
+#define USBTV_ISOC_PACKETS      8
+
+#define USBTV_WIDTH             720
+#define USBTV_HEIGHT            480
+
+#define USBTV_CHUNK_SIZE        256
+#define USBTV_CHUNK             240
+#define USBTV_CHUNKS            (USBTV_WIDTH * USBTV_HEIGHT \
+                                        / 2 / USBTV_CHUNK)
+
+/* Chunk header. */
+#define USBTV_MAGIC_OK(chunk)   ((be32_to_cpu(chunk[0]) & 0xff000000) \
+                                                        == 0x88000000)
+#define USBTV_FRAME_ID(chunk)   ((be32_to_cpu(chunk[0]) & 0x00ff0000) >> 16)
+#define USBTV_ODD(chunk)        ((be32_to_cpu(chunk[0]) & 0x0000f000) >> 15)
+#define USBTV_CHUNK_NO(chunk)   (be32_to_cpu(chunk[0]) & 0x00000fff)
+
+/* A single videobuf2 frame buffer. */
+struct usbtv_buf {
+        struct vb2_buffer vb;
+        struct list_head list;
+};
+
+/* Per-device structure. */
+struct usbtv {
+        struct device *dev;
+        struct usb_device *udev;
+        struct v4l2_device v4l2_dev;
+        struct video_device vdev;
+        struct vb2_queue vb2q;
+        struct mutex v4l2_lock;
+        struct mutex vb2q_lock;
+
+        /* List of videobuf2 buffers protected by a lock. */
+        spinlock_t buflock;
+        struct list_head bufs;
+
+        /* Number of currently processed frame, useful find
+         * out when a new one begins. */
+        u32 frame_id;
+
+        int iso_size;
+        unsigned int sequence;
+        struct urb *isoc_urbs[USBTV_ISOC_TRANSFERS];
+};
+
+static int usbtv_setup_capture(struct usbtv *usbtv)
+{
+        int ret;
+        int pipe = usb_rcvctrlpipe(usbtv->udev, 0);
+        int i;
+        static const u16 protoregs[][2] = {
+                /* These seem to enable the device. */
+                { USBTV_BASE + 0x0008, 0x0001 },
+                { USBTV_BASE + 0x01d0, 0x00ff },
+                { USBTV_BASE + 0x01d9, 0x0002 },
+
+                /* These seem to influence color parameters, such as
+                 * brightness, etc. */
+                { USBTV_BASE + 0x0239, 0x0040 },
+                { USBTV_BASE + 0x0240, 0x0000 },
+                { USBTV_BASE + 0x0241, 0x0000 },
+                { USBTV_BASE + 0x0242, 0x0002 },
+                { USBTV_BASE + 0x0243, 0x0080 },
+                { USBTV_BASE + 0x0244, 0x0012 },
+                { USBTV_BASE + 0x0245, 0x0090 },
+                { USBTV_BASE + 0x0246, 0x0000 },
+
+                { USBTV_BASE + 0x0278, 0x002d },
+                { USBTV_BASE + 0x0279, 0x000a },
+                { USBTV_BASE + 0x027a, 0x0032 },
+                { 0xf890, 0x000c },
+                { 0xf894, 0x0086 },
+
+                { USBTV_BASE + 0x00ac, 0x00c0 },
+                { USBTV_BASE + 0x00ad, 0x0000 },
+                { USBTV_BASE + 0x00a2, 0x0012 },
+                { USBTV_BASE + 0x00a3, 0x00e0 },
+                { USBTV_BASE + 0x00a4, 0x0028 },
+                { USBTV_BASE + 0x00a5, 0x0082 },
+                { USBTV_BASE + 0x00a7, 0x0080 },
+                { USBTV_BASE + 0x0000, 0x0014 },
+                { USBTV_BASE + 0x0006, 0x0003 },
+                { USBTV_BASE + 0x0090, 0x0099 },
+                { USBTV_BASE + 0x0091, 0x0090 },
+                { USBTV_BASE + 0x0094, 0x0068 },
+                { USBTV_BASE + 0x0095, 0x0070 },
+                { USBTV_BASE + 0x009c, 0x0030 },
+                { USBTV_BASE + 0x009d, 0x00c0 },
+                { USBTV_BASE + 0x009e, 0x00e0 },
+                { USBTV_BASE + 0x0019, 0x0006 },
+                { USBTV_BASE + 0x008c, 0x00ba },
+                { USBTV_BASE + 0x0101, 0x00ff },
+                { USBTV_BASE + 0x010c, 0x00b3 },
+                { USBTV_BASE + 0x01b2, 0x0080 },
+                { USBTV_BASE + 0x01b4, 0x00a0 },
+                { USBTV_BASE + 0x014c, 0x00ff },
+                { USBTV_BASE + 0x014d, 0x00ca },
+                { USBTV_BASE + 0x0113, 0x0053 },
+                { USBTV_BASE + 0x0119, 0x008a },
+                { USBTV_BASE + 0x013c, 0x0003 },
+                { USBTV_BASE + 0x0150, 0x009c },
+                { USBTV_BASE + 0x0151, 0x0071 },
+                { USBTV_BASE + 0x0152, 0x00c6 },
+                { USBTV_BASE + 0x0153, 0x0084 },
+                { USBTV_BASE + 0x0154, 0x00bc },
+                { USBTV_BASE + 0x0155, 0x00a0 },
+                { USBTV_BASE + 0x0156, 0x00a0 },
+                { USBTV_BASE + 0x0157, 0x009c },
+                { USBTV_BASE + 0x0158, 0x001f },
+                { USBTV_BASE + 0x0159, 0x0006 },
+                { USBTV_BASE + 0x015d, 0x0000 },
+
+                { USBTV_BASE + 0x0284, 0x0088 },
+                { USBTV_BASE + 0x0003, 0x0004 },
+                { USBTV_BASE + 0x001a, 0x0079 },
+                { USBTV_BASE + 0x0100, 0x00d3 },
+                { USBTV_BASE + 0x010e, 0x0068 },
+                { USBTV_BASE + 0x010f, 0x009c },
+                { USBTV_BASE + 0x0112, 0x00f0 },
+                { USBTV_BASE + 0x0115, 0x0015 },
+                { USBTV_BASE + 0x0117, 0x0000 },
+                { USBTV_BASE + 0x0118, 0x00fc },
+                { USBTV_BASE + 0x012d, 0x0004 },
+                { USBTV_BASE + 0x012f, 0x0008 },
+                { USBTV_BASE + 0x0220, 0x002e },
+                { USBTV_BASE + 0x0225, 0x0008 },
+                { USBTV_BASE + 0x024e, 0x0002 },
+                { USBTV_BASE + 0x024f, 0x0001 },
+                { USBTV_BASE + 0x0254, 0x005f },
+                { USBTV_BASE + 0x025a, 0x0012 },
+                { USBTV_BASE + 0x025b, 0x0001 },
+                { USBTV_BASE + 0x0263, 0x001c },
+                { USBTV_BASE + 0x0266, 0x0011 },
+                { USBTV_BASE + 0x0267, 0x0005 },
+                { USBTV_BASE + 0x024e, 0x0002 },
+                { USBTV_BASE + 0x024f, 0x0002 },
+        };
+
+        for (i = 0; i < ARRAY_SIZE(protoregs); i++) {
+                u16 index = protoregs[i][0];
+                u16 value = protoregs[i][1];
+
+                ret = usb_control_msg(usbtv->udev, pipe, USBTV_REQUEST_REG,
+                        USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
+                        value, index, NULL, 0, 0);
+                if (ret < 0)
+                        return ret;
+        }
+
+        return 0;
+}
+
+/* Called for each 256-byte image chunk.
+ * First word identifies the chunk, followed by 240 words of image
+ * data and padding. */
+static void usbtv_image_chunk(struct usbtv *usbtv, u32 *chunk)
+{
+        int frame_id, odd, chunk_no;
+        u32 *frame;
+        struct usbtv_buf *buf;
+        unsigned long flags;
+
+        /* Ignore corrupted lines. */
+        if (!USBTV_MAGIC_OK(chunk))
+                return;
+        frame_id = USBTV_FRAME_ID(chunk);
+        odd = USBTV_ODD(chunk);
+        chunk_no = USBTV_CHUNK_NO(chunk);
+
+        /* Deinterlace. TODO: Use interlaced frame format. */
+        chunk_no = (chunk_no - chunk_no % 3) * 2 + chunk_no % 3;
+        chunk_no += !odd * 3;
+
+        if (chunk_no >= USBTV_CHUNKS)
+                return;
+
+        /* Beginning of a frame. */
+        if (chunk_no == 0)
+                usbtv->frame_id = frame_id;
+
+        spin_lock_irqsave(&usbtv->buflock, flags);
+        if (list_empty(&usbtv->bufs)) {
+                /* No free buffers. Userspace likely too slow. */
+                spin_unlock_irqrestore(&usbtv->buflock, flags);
+                return;
+        }
+
+        /* First available buffer. */
+        buf = list_first_entry(&usbtv->bufs, struct usbtv_buf, list);
+        frame = vb2_plane_vaddr(&buf->vb, 0);
+
+        /* Copy the chunk. */
+        memcpy(&frame[chunk_no * USBTV_CHUNK], &chunk[1],
+                        USBTV_CHUNK * sizeof(chunk[1]));
+
+        /* Last chunk in a frame, signalling an end */
+        if (usbtv->frame_id && chunk_no == USBTV_CHUNKS-1) {
+                int size = vb2_plane_size(&buf->vb, 0);
+
+                buf->vb.v4l2_buf.field = V4L2_FIELD_INTERLACED;
+                buf->vb.v4l2_buf.sequence = usbtv->sequence++;
+                v4l2_get_timestamp(&buf->vb.v4l2_buf.timestamp);
+                vb2_set_plane_payload(&buf->vb, 0, size);
+                vb2_buffer_done(&buf->vb, VB2_BUF_STATE_DONE);
+                list_del(&buf->list);
+        }
+
+        spin_unlock_irqrestore(&usbtv->buflock, flags);
+}
+
+/* Got image data. Each packet contains a number of 256-word chunks we
+ * compose the image from. */
+static void usbtv_iso_cb(struct urb *ip)
+{
+        int ret;
+        int i;
+        struct usbtv *usbtv = (struct usbtv *)ip->context;
+
+        switch (ip->status) {
+        /* All fine. */
+        case 0:
+                break;
+        /* Device disconnected or capture stopped? */
+        case -ENODEV:
+        case -ENOENT:
+        case -ECONNRESET:
+        case -ESHUTDOWN:
+                return;
+        /* Unknown error. Retry. */
+        default:
+                dev_warn(usbtv->dev, "Bad response for ISO request.\n");
+                goto resubmit;
+        }
+
+        for (i = 0; i < ip->number_of_packets; i++) {
+                int size = ip->iso_frame_desc[i].actual_length;
+                unsigned char *data = ip->transfer_buffer +
+                                ip->iso_frame_desc[i].offset;
+                int offset;
+
+                for (offset = 0; USBTV_CHUNK_SIZE * offset < size; offset++)
+                        usbtv_image_chunk(usbtv,
+                                (u32 *)&data[USBTV_CHUNK_SIZE * offset]);
+        }
+
+resubmit:
+        ret = usb_submit_urb(ip, GFP_ATOMIC);
+        if (ret < 0)
+                dev_warn(usbtv->dev, "Could not resubmit ISO URB\n");
+}
+
+static struct urb *usbtv_setup_iso_transfer(struct usbtv *usbtv)
+{
+        struct urb *ip;
+        int size = usbtv->iso_size;
+        int i;
+
+        ip = usb_alloc_urb(USBTV_ISOC_PACKETS, GFP_KERNEL);
+        if (ip == NULL)
+                return NULL;
+
+        ip->dev = usbtv->udev;
+        ip->context = usbtv;
+        ip->pipe = usb_rcvisocpipe(usbtv->udev, USBTV_VIDEO_ENDP);
+        ip->interval = 1;
+        ip->transfer_flags = URB_ISO_ASAP;
+        ip->transfer_buffer = kzalloc(size * USBTV_ISOC_PACKETS,
+                                                GFP_KERNEL);
+        ip->complete = usbtv_iso_cb;
+        ip->number_of_packets = USBTV_ISOC_PACKETS;
+        ip->transfer_buffer_length = size * USBTV_ISOC_PACKETS;
+        for (i = 0; i < USBTV_ISOC_PACKETS; i++) {
+                ip->iso_frame_desc[i].offset = size * i;
+                ip->iso_frame_desc[i].length = size;
+        }
+
+        return ip;
+}
+
+static void usbtv_stop(struct usbtv *usbtv)
+{
+        int i;
+        unsigned long flags;
+
+        /* Cancel running transfers. */
+        for (i = 0; i < USBTV_ISOC_TRANSFERS; i++) {
+                struct urb *ip = usbtv->isoc_urbs[i];
+                if (ip == NULL)
+                        continue;
+                usb_kill_urb(ip);
+                kfree(ip->transfer_buffer);
+                usb_free_urb(ip);
+                usbtv->isoc_urbs[i] = NULL;
+        }
+
+        /* Return buffers to userspace. */
+        spin_lock_irqsave(&usbtv->buflock, flags);
+        while (!list_empty(&usbtv->bufs)) {
+                struct usbtv_buf *buf = list_first_entry(&usbtv->bufs,
+                                                struct usbtv_buf, list);
+                vb2_buffer_done(&buf->vb, VB2_BUF_STATE_ERROR);
+                list_del(&buf->list);
+        }
+        spin_unlock_irqrestore(&usbtv->buflock, flags);
+}
+
+static int usbtv_start(struct usbtv *usbtv)
+{
+        int i;
+        int ret;
+
+        ret = usb_set_interface(usbtv->udev, 0, 0);
+        if (ret < 0)
+                return ret;
+
+        ret = usbtv_setup_capture(usbtv);
+        if (ret < 0)
+                return ret;
+
+        ret = usb_set_interface(usbtv->udev, 0, 1);
+        if (ret < 0)
+                return ret;
+
+        for (i = 0; i < USBTV_ISOC_TRANSFERS; i++) {
+                struct urb *ip;
+
+                ip = usbtv_setup_iso_transfer(usbtv);
+                if (ip == NULL) {
+                        ret = -ENOMEM;
+                        goto start_fail;
+                }
+                usbtv->isoc_urbs[i] = ip;
+
+                ret = usb_submit_urb(ip, GFP_KERNEL);
+                if (ret < 0)
+                        goto start_fail;
+        }
+
+        return 0;
+
+start_fail:
+        usbtv_stop(usbtv);
+        return ret;
+}
+
+struct usb_device_id usbtv_id_table[] = {
+        { USB_DEVICE(0x1b71, 0x3002) },
+        {}
+};
+MODULE_DEVICE_TABLE(usb, usbtv_id_table);
+
+static int usbtv_querycap(struct file *file, void *priv,
+                                struct v4l2_capability *cap)
+{
+        struct usbtv *dev = video_drvdata(file);
+
+        strlcpy(cap->driver, "usbtv", sizeof(cap->driver));
+        strlcpy(cap->card, "usbtv", sizeof(cap->card));
+        usb_make_path(dev->udev, cap->bus_info, sizeof(cap->bus_info));
+        cap->device_caps = V4L2_CAP_VIDEO_CAPTURE;
+        cap->device_caps |= V4L2_CAP_READWRITE | V4L2_CAP_STREAMING;
+        cap->capabilities = cap->device_caps | V4L2_CAP_DEVICE_CAPS;
+        return 0;
+}
+
+static int usbtv_enum_input(struct file *file, void *priv,
+                                        struct v4l2_input *i)
+{
+        if (i->index > 0)
+                return -EINVAL;
+
+        strlcpy(i->name, "Composite", sizeof(i->name));
+        i->type = V4L2_INPUT_TYPE_CAMERA;
+        i->std = V4L2_STD_525_60;
+        return 0;
+}
+
+static int usbtv_enum_fmt_vid_cap(struct file *file, void  *priv,
+                                        struct v4l2_fmtdesc *f)
+{
+        if (f->index > 0)
+                return -EINVAL;
+
+        strlcpy(f->description, "16 bpp YUY2, 4:2:2, packed",
+                                        sizeof(f->description));
+        f->pixelformat = V4L2_PIX_FMT_YUYV;
+        return 0;
+}
+
+static int usbtv_fmt_vid_cap(struct file *file, void *priv,
+                                        struct v4l2_format *f)
+{
+        f->fmt.pix.width = USBTV_WIDTH;
+        f->fmt.pix.height = USBTV_HEIGHT;
+        f->fmt.pix.pixelformat = V4L2_PIX_FMT_YUYV;
+        f->fmt.pix.field = V4L2_FIELD_INTERLACED;
+        f->fmt.pix.bytesperline = USBTV_WIDTH * 2;
+        f->fmt.pix.sizeimage = (f->fmt.pix.bytesperline * f->fmt.pix.height);
+        f->fmt.pix.colorspace = V4L2_COLORSPACE_SMPTE170M;
+        f->fmt.pix.priv = 0;
+        return 0;
+}
+
+static int usbtv_g_std(struct file *file, void *priv, v4l2_std_id *norm)
+{
+        *norm = V4L2_STD_525_60;
+        return 0;
+}
+
+static int usbtv_g_input(struct file *file, void *priv, unsigned int *i)
+{
+        *i = 0;
+        return 0;
+}
+
+static int usbtv_s_input(struct file *file, void *priv, unsigned int i)
+{
+        if (i > 0)
+                return -EINVAL;
+        return 0;
+}
+
+static int usbtv_s_std(struct file *file, void *priv, v4l2_std_id norm)
+{
+        if (norm & V4L2_STD_525_60)
+                return 0;
+        return -EINVAL;
+}
+
+struct v4l2_ioctl_ops usbtv_ioctl_ops = {
+        .vidioc_querycap = usbtv_querycap,
+        .vidioc_enum_input = usbtv_enum_input,
+        .vidioc_enum_fmt_vid_cap = usbtv_enum_fmt_vid_cap,
+        .vidioc_g_fmt_vid_cap = usbtv_fmt_vid_cap,
+        .vidioc_try_fmt_vid_cap = usbtv_fmt_vid_cap,
+        .vidioc_s_fmt_vid_cap = usbtv_fmt_vid_cap,
+        .vidioc_g_std = usbtv_g_std,
+        .vidioc_s_std = usbtv_s_std,
+        .vidioc_g_input = usbtv_g_input,
+        .vidioc_s_input = usbtv_s_input,
+
+        .vidioc_reqbufs = vb2_ioctl_reqbufs,
+        .vidioc_prepare_buf = vb2_ioctl_prepare_buf,
+        .vidioc_querybuf = vb2_ioctl_querybuf,
+        .vidioc_create_bufs = vb2_ioctl_create_bufs,
+        .vidioc_qbuf = vb2_ioctl_qbuf,
+        .vidioc_dqbuf = vb2_ioctl_dqbuf,
+        .vidioc_streamon = vb2_ioctl_streamon,
+        .vidioc_streamoff = vb2_ioctl_streamoff,
+};
+
+struct v4l2_file_operations usbtv_fops = {
+        .owner = THIS_MODULE,
+        .unlocked_ioctl = video_ioctl2,
+        .mmap = vb2_fop_mmap,
+        .open = v4l2_fh_open,
+        .release = vb2_fop_release,
+        .read = vb2_fop_read,
+        .poll = vb2_fop_poll,
+};
+
+static int usbtv_queue_setup(struct vb2_queue *vq,
+        const struct v4l2_format *v4l_fmt, unsigned int *nbuffers,
+        unsigned int *nplanes, unsigned int sizes[], void *alloc_ctxs[])
+{
+        if (*nbuffers < 2)
+                *nbuffers = 2;
+        *nplanes = 1;
+        sizes[0] = USBTV_CHUNK * USBTV_CHUNKS * sizeof(u32);
+
+        return 0;
+}
+
+static void usbtv_buf_queue(struct vb2_buffer *vb)
+{
+        struct usbtv *usbtv = vb2_get_drv_priv(vb->vb2_queue);
+        struct usbtv_buf *buf = container_of(vb, struct usbtv_buf, vb);
+        unsigned long flags;
+
+        if (usbtv->udev == NULL) {
+                vb2_buffer_done(vb, VB2_BUF_STATE_ERROR);
+                return;
+        }
+
+        spin_lock_irqsave(&usbtv->buflock, flags);
+        list_add_tail(&buf->list, &usbtv->bufs);
+        spin_unlock_irqrestore(&usbtv->buflock, flags);
+}
+
+static int usbtv_start_streaming(struct vb2_queue *vq, unsigned int count)
+{
+        struct usbtv *usbtv = vb2_get_drv_priv(vq);
+
+        if (usbtv->udev == NULL)
+                return -ENODEV;
+
+        return usbtv_start(usbtv);
+}
+
+static int usbtv_stop_streaming(struct vb2_queue *vq)
+{
+        struct usbtv *usbtv = vb2_get_drv_priv(vq);
+
+        if (usbtv->udev == NULL)
+                return -ENODEV;
+
+        usbtv_stop(usbtv);
+        return 0;
+}
+
+struct vb2_ops usbtv_vb2_ops = {
+        .queue_setup = usbtv_queue_setup,
+        .buf_queue = usbtv_buf_queue,
+        .start_streaming = usbtv_start_streaming,
+        .stop_streaming = usbtv_stop_streaming,
+};
+
+static void usbtv_release(struct v4l2_device *v4l2_dev)
+{
+        struct usbtv *usbtv = container_of(v4l2_dev, struct usbtv, v4l2_dev);
+
+        v4l2_device_unregister(&usbtv->v4l2_dev);
+        vb2_queue_release(&usbtv->vb2q);
+        kfree(usbtv);
+}
+
+static int usbtv_probe(struct usb_interface *intf,
+        const struct usb_device_id *id)
+{
+        int ret;
+        int size;
+        struct device *dev = &intf->dev;
+        struct usbtv *usbtv;
+
+        /* Checks that the device is what we think it is. */
+        if (intf->num_altsetting != 2)
+                return -ENODEV;
+        if (intf->altsetting[1].desc.bNumEndpoints != 4)
+                return -ENODEV;
+
+        /* Packet size is split into 11 bits of base size and count of
+         * extra multiplies of it.*/
+        size = usb_endpoint_maxp(&intf->altsetting[1].endpoint[0].desc);
+        size = (size & 0x07ff) * (((size & 0x1800) >> 11) + 1);
+
+        /* Device structure */
+        usbtv = kzalloc(sizeof(struct usbtv), GFP_KERNEL);
+        if (usbtv == NULL)
+                return -ENOMEM;
+        usbtv->dev = dev;
+        usbtv->udev = usb_get_dev(interface_to_usbdev(intf));
+        usbtv->iso_size = size;
+        spin_lock_init(&usbtv->buflock);
+        mutex_init(&usbtv->v4l2_lock);
+        mutex_init(&usbtv->vb2q_lock);
+        INIT_LIST_HEAD(&usbtv->bufs);
+
+        /* videobuf2 structure */
+        usbtv->vb2q.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+        usbtv->vb2q.io_modes = VB2_MMAP | VB2_USERPTR | VB2_READ;
+        usbtv->vb2q.drv_priv = usbtv;
+        usbtv->vb2q.buf_struct_size = sizeof(struct usbtv_buf);
+        usbtv->vb2q.ops = &usbtv_vb2_ops;
+        usbtv->vb2q.mem_ops = &vb2_vmalloc_memops;
+        usbtv->vb2q.timestamp_type = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
+        usbtv->vb2q.lock = &usbtv->vb2q_lock;
+        ret = vb2_queue_init(&usbtv->vb2q);
+        if (ret < 0) {
+                dev_warn(dev, "Could not initialize videobuf2 queue\n");
+                goto usbtv_fail;
+        }
+
+        /* v4l2 structure */
+        usbtv->v4l2_dev.release = usbtv_release;
+        ret = v4l2_device_register(dev, &usbtv->v4l2_dev);
+        if (ret < 0) {
+                dev_warn(dev, "Could not register v4l2 device\n");
+                goto v4l2_fail;
+        }
+
+        usb_set_intfdata(intf, usbtv);
+
+        /* Video structure */
+        strlcpy(usbtv->vdev.name, "usbtv", sizeof(usbtv->vdev.name));
+        usbtv->vdev.v4l2_dev = &usbtv->v4l2_dev;
+        usbtv->vdev.release = video_device_release_empty;
+        usbtv->vdev.fops = &usbtv_fops;
+        usbtv->vdev.ioctl_ops = &usbtv_ioctl_ops;
+        usbtv->vdev.tvnorms = V4L2_STD_525_60;
+        usbtv->vdev.queue = &usbtv->vb2q;
+        usbtv->vdev.lock = &usbtv->v4l2_lock;
+        set_bit(V4L2_FL_USE_FH_PRIO, &usbtv->vdev.flags);
+        video_set_drvdata(&usbtv->vdev, usbtv);
+        ret = video_register_device(&usbtv->vdev, VFL_TYPE_GRABBER, -1);
+        if (ret < 0) {
+                dev_warn(dev, "Could not register video device\n");
+                goto vdev_fail;
+        }
+
+        dev_info(dev, "Fushicai USBTV007 Video Grabber\n");
+        return 0;
+
+vdev_fail:
+        v4l2_device_unregister(&usbtv->v4l2_dev);
+v4l2_fail:
+        vb2_queue_release(&usbtv->vb2q);
+usbtv_fail:
+        kfree(usbtv);
+
+        return ret;
+}
+
+static void usbtv_disconnect(struct usb_interface *intf)
+{
+        struct usbtv *usbtv = usb_get_intfdata(intf);
+
+        mutex_lock(&usbtv->vb2q_lock);
+        mutex_lock(&usbtv->v4l2_lock);
+
+        usbtv_stop(usbtv);
+        usb_set_intfdata(intf, NULL);
+        video_unregister_device(&usbtv->vdev);
+        v4l2_device_disconnect(&usbtv->v4l2_dev);
+        usb_put_dev(usbtv->udev);
+        usbtv->udev = NULL;
+
+        mutex_unlock(&usbtv->v4l2_lock);
+        mutex_unlock(&usbtv->vb2q_lock);
+
+        v4l2_device_put(&usbtv->v4l2_dev);
+}
+
+MODULE_AUTHOR("Lubomir Rintel");
+MODULE_DESCRIPTION("Fushicai USBTV007 Video Grabber Driver");
+MODULE_LICENSE("Dual BSD/GPL");
+
+struct usb_driver usbtv_usb_driver = {
+        .name = "usbtv",
+        .id_table = usbtv_id_table,
+        .probe = usbtv_probe,
+        .disconnect = usbtv_disconnect,
+};
+
+module_usb_driver(usbtv_usb_driver);