@@ -1,5 +1,5 @@
uvcvideo-objs := uvc_driver.o uvc_queue.o uvc_v4l2.o uvc_video.o uvc_ctrl.o \
- uvc_status.o uvc_isight.o uvc_debugfs.o
+ uvc_status.o uvc_isight.o uvc_debugfs.o uvc_metadata.o
ifeq ($(CONFIG_MEDIA_CONTROLLER),y)
uvcvideo-objs += uvc_entity.o
endif
@@ -1883,6 +1883,7 @@ static void uvc_unregister_video(struct uvc_device *dev)
continue;
video_unregister_device(&stream->vdev);
+ video_unregister_device(&stream->meta.vdev);
uvc_debugfs_cleanup_stream(stream);
}
@@ -1930,6 +1931,9 @@ int uvc_register_video_device(struct uvc_device *dev,
case V4L2_BUF_TYPE_VIDEO_OUTPUT:
vdev->device_caps = V4L2_CAP_VIDEO_OUTPUT | V4L2_CAP_STREAMING;
break;
+ case V4L2_BUF_TYPE_META_CAPTURE:
+ vdev->device_caps = V4L2_CAP_META_CAPTURE | V4L2_CAP_STREAMING;
+ break;
}
strlcpy(vdev->name, dev->name, sizeof vdev->name);
@@ -1965,7 +1969,8 @@ static int uvc_register_video(struct uvc_device *dev,
}
if (stream->type == V4L2_BUF_TYPE_VIDEO_CAPTURE)
- stream->chain->caps |= V4L2_CAP_VIDEO_CAPTURE;
+ stream->chain->caps |= V4L2_CAP_VIDEO_CAPTURE
+ | V4L2_CAP_META_CAPTURE;
else
stream->chain->caps |= V4L2_CAP_VIDEO_OUTPUT;
@@ -2003,6 +2008,11 @@ static int uvc_register_terms(struct uvc_device *dev,
if (ret < 0)
return ret;
+ /* Register a metadata node, but ignore a possible failure,
+ * complete registration of video nodes anyway.
+ */
+ uvc_meta_register(stream);
+
term->vdev = &stream->vdev;
}
@@ -2037,6 +2047,7 @@ static int uvc_register_chains(struct uvc_device *dev)
struct uvc_device_info {
u32 quirks;
+ u32 meta_format;
};
static int uvc_probe(struct usb_interface *intf,
@@ -2074,6 +2085,8 @@ static int uvc_probe(struct usb_interface *intf,
dev->intfnum = intf->cur_altsetting->desc.bInterfaceNumber;
dev->quirks = (uvc_quirks_param == -1)
? quirks : uvc_quirks_param;
+ if (info)
+ dev->meta_format = info->meta_format;
if (udev->product != NULL)
strlcpy(dev->name, udev->product, sizeof dev->name);
@@ -100,7 +100,7 @@ static int isight_decode(struct uvc_video_queue *queue, struct uvc_buffer *buf,
}
void uvc_video_decode_isight(struct urb *urb, struct uvc_streaming *stream,
- struct uvc_buffer *buf)
+ struct uvc_buffer *buf, struct uvc_buffer *meta_buf)
{
int ret, i;
new file mode 100644
@@ -0,0 +1,179 @@
+/*
+ * uvc_metadata.c -- USB Video Class driver - Metadata handling
+ *
+ * Copyright (C) 2016
+ * Guennadi Liakhovetski (guennadi.liakhovetski@intel.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.
+ */
+
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/usb.h>
+#include <linux/videodev2.h>
+
+#include <media/v4l2-ioctl.h>
+#include <media/videobuf2-v4l2.h>
+#include <media/videobuf2-vmalloc.h>
+
+#include "uvcvideo.h"
+
+/* -----------------------------------------------------------------------------
+ * V4L2 ioctls
+ */
+
+static int uvc_meta_v4l2_querycap(struct file *file, void *fh,
+ struct v4l2_capability *cap)
+{
+ struct v4l2_fh *vfh = file->private_data;
+ struct uvc_streaming *stream = video_get_drvdata(vfh->vdev);
+ struct uvc_video_chain *chain = stream->chain;
+
+ strlcpy(cap->driver, "uvcvideo", sizeof(cap->driver));
+ strlcpy(cap->card, vfh->vdev->name, sizeof(cap->card));
+ usb_make_path(stream->dev->udev, cap->bus_info, sizeof(cap->bus_info));
+ cap->capabilities = V4L2_CAP_DEVICE_CAPS | V4L2_CAP_STREAMING
+ | chain->caps;
+
+ return 0;
+}
+
+static int uvc_meta_v4l2_get_format(struct file *file, void *fh,
+ struct v4l2_format *format)
+{
+ struct v4l2_fh *vfh = file->private_data;
+ struct uvc_streaming *stream = video_get_drvdata(vfh->vdev);
+ struct v4l2_meta_format *fmt = &format->fmt.meta;
+
+ if (format->type != vfh->vdev->queue->type)
+ return -EINVAL;
+
+ memset(fmt, 0, sizeof(*fmt));
+
+ fmt->dataformat = stream->meta.format;
+ fmt->buffersize = UVC_METATADA_BUF_SIZE;
+
+ return 0;
+}
+
+static int uvc_meta_v4l2_try_format(struct file *file, void *fh,
+ struct v4l2_format *format)
+{
+ struct v4l2_fh *vfh = file->private_data;
+ struct uvc_streaming *stream = video_get_drvdata(vfh->vdev);
+ struct uvc_device *dev = stream->dev;
+ struct v4l2_meta_format *fmt = &format->fmt.meta;
+ u32 fmeta = fmt->dataformat;
+
+ if (format->type != vfh->vdev->queue->type)
+ return -EINVAL;
+
+ memset(fmt, 0, sizeof(*fmt));
+
+ fmt->dataformat = fmeta == dev->meta_format ? fmeta : V4L2_META_FMT_UVC;
+ fmt->buffersize = UVC_METATADA_BUF_SIZE;
+
+ return 0;
+}
+
+static int uvc_meta_v4l2_set_format(struct file *file, void *fh,
+ struct v4l2_format *format)
+{
+ struct v4l2_fh *vfh = file->private_data;
+ struct uvc_streaming *stream = video_get_drvdata(vfh->vdev);
+ struct v4l2_meta_format *fmt = &format->fmt.meta;
+ int ret;
+
+ ret = uvc_meta_v4l2_try_format(file, fh, format);
+ if (ret < 0)
+ return ret;
+
+ /*
+ * We could in principle switch at any time, also during streaming.
+ * Metadata buffers would still be perfectly parseable, but it's more
+ * consistent and cleaner to disallow that.
+ */
+ mutex_lock(&stream->mutex);
+
+ if (uvc_queue_allocated(&stream->queue))
+ ret = -EBUSY;
+ else
+ stream->meta.format = fmt->dataformat;
+
+ mutex_unlock(&stream->mutex);
+
+ return ret;
+}
+
+static int uvc_meta_v4l2_enum_formats(struct file *file, void *fh,
+ struct v4l2_fmtdesc *fdesc)
+{
+ struct v4l2_fh *vfh = file->private_data;
+ struct uvc_streaming *stream = video_get_drvdata(vfh->vdev);
+ struct uvc_device *dev = stream->dev;
+ u32 index = fdesc->index;
+
+ if (fdesc->type != vfh->vdev->queue->type ||
+ index > 1U || (index && !dev->meta_format))
+ return -EINVAL;
+
+ memset(fdesc, 0, sizeof(*fdesc));
+
+ fdesc->type = vfh->vdev->queue->type;
+ fdesc->index = index;
+ fdesc->pixelformat = index ? dev->meta_format : V4L2_META_FMT_UVC;
+
+ return 0;
+}
+
+static const struct v4l2_ioctl_ops uvc_meta_ioctl_ops = {
+ .vidioc_querycap = uvc_meta_v4l2_querycap,
+ .vidioc_g_fmt_meta_cap = uvc_meta_v4l2_get_format,
+ .vidioc_s_fmt_meta_cap = uvc_meta_v4l2_set_format,
+ .vidioc_try_fmt_meta_cap = uvc_meta_v4l2_try_format,
+ .vidioc_enum_fmt_meta_cap = uvc_meta_v4l2_enum_formats,
+ .vidioc_reqbufs = vb2_ioctl_reqbufs,
+ .vidioc_querybuf = vb2_ioctl_querybuf,
+ .vidioc_qbuf = vb2_ioctl_qbuf,
+ .vidioc_dqbuf = vb2_ioctl_dqbuf,
+ .vidioc_create_bufs = vb2_ioctl_create_bufs,
+ .vidioc_prepare_buf = vb2_ioctl_prepare_buf,
+ .vidioc_streamon = vb2_ioctl_streamon,
+ .vidioc_streamoff = vb2_ioctl_streamoff,
+};
+
+/* -----------------------------------------------------------------------------
+ * V4L2 File Operations
+ */
+
+static const struct v4l2_file_operations uvc_meta_fops = {
+ .owner = THIS_MODULE,
+ .unlocked_ioctl = video_ioctl2,
+ .open = v4l2_fh_open,
+ .release = vb2_fop_release,
+ .poll = vb2_fop_poll,
+ .mmap = vb2_fop_mmap,
+};
+
+int uvc_meta_register(struct uvc_streaming *stream)
+{
+ struct uvc_device *dev = stream->dev;
+ struct video_device *vdev = &stream->meta.vdev;
+ struct uvc_video_queue *queue = &stream->meta.queue;
+
+ stream->meta.format = V4L2_META_FMT_UVC;
+
+ /*
+ * The video interface queue uses manual locking and thus does not set
+ * the queue pointer. Set it manually here.
+ */
+ vdev->queue = &queue->queue;
+
+ return uvc_register_video_device(dev, stream, vdev, queue,
+ V4L2_BUF_TYPE_META_CAPTURE,
+ &uvc_meta_fops, &uvc_meta_ioctl_ops);
+}
@@ -79,8 +79,19 @@ static int uvc_queue_setup(struct vb2_queue *vq,
unsigned int sizes[], struct device *alloc_devs[])
{
struct uvc_video_queue *queue = vb2_get_drv_priv(vq);
- struct uvc_streaming *stream = uvc_queue_to_stream(queue);
- unsigned size = stream->ctrl.dwMaxVideoFrameSize;
+ struct uvc_streaming *stream;
+ unsigned int size;
+
+ switch (vq->type) {
+ case V4L2_BUF_TYPE_META_CAPTURE:
+ size = UVC_METATADA_BUF_SIZE;
+ break;
+
+ default:
+ stream = uvc_queue_to_stream(queue);
+ size = stream->ctrl.dwMaxVideoFrameSize;
+ break;
+ }
/*
* When called with plane sizes, validate them. The driver supports
@@ -114,7 +125,7 @@ static int uvc_buffer_prepare(struct vb2_buffer *vb)
buf->error = 0;
buf->mem = vb2_plane_vaddr(vb, 0);
buf->length = vb2_plane_size(vb, 0);
- if (vb->type == V4L2_BUF_TYPE_VIDEO_CAPTURE)
+ if (vb->type != V4L2_BUF_TYPE_VIDEO_OUTPUT)
buf->bytesused = 0;
else
buf->bytesused = vb2_get_plane_payload(vb, 0);
@@ -177,10 +188,10 @@ static int uvc_start_streaming(struct vb2_queue *vq, unsigned int count)
static void uvc_stop_streaming(struct vb2_queue *vq)
{
struct uvc_video_queue *queue = vb2_get_drv_priv(vq);
- struct uvc_streaming *stream = uvc_queue_to_stream(queue);
unsigned long flags;
- uvc_video_enable(stream, 0);
+ if (vq->type != V4L2_BUF_TYPE_META_CAPTURE)
+ uvc_video_enable(uvc_queue_to_stream(queue), 0);
spin_lock_irqsave(&queue->irqlock, flags);
uvc_queue_return_buffers(queue, UVC_BUF_STATE_ERROR);
@@ -198,20 +209,39 @@ static void uvc_stop_streaming(struct vb2_queue *vq)
.stop_streaming = uvc_stop_streaming,
};
+static const struct vb2_ops uvc_meta_queue_qops = {
+ .queue_setup = uvc_queue_setup,
+ .buf_prepare = uvc_buffer_prepare,
+ .buf_queue = uvc_buffer_queue,
+ .wait_prepare = vb2_ops_wait_prepare,
+ .wait_finish = vb2_ops_wait_finish,
+ .stop_streaming = uvc_stop_streaming,
+};
+
int uvc_queue_init(struct uvc_video_queue *queue, enum v4l2_buf_type type,
int drop_corrupted)
{
int ret;
queue->queue.type = type;
- queue->queue.io_modes = VB2_MMAP | VB2_USERPTR | VB2_DMABUF;
+ queue->queue.io_modes = VB2_MMAP | VB2_USERPTR;
queue->queue.drv_priv = queue;
queue->queue.buf_struct_size = sizeof(struct uvc_buffer);
- queue->queue.ops = &uvc_queue_qops;
queue->queue.mem_ops = &vb2_vmalloc_memops;
queue->queue.timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC
| V4L2_BUF_FLAG_TSTAMP_SRC_SOE;
queue->queue.lock = &queue->mutex;
+
+ switch (type) {
+ case V4L2_BUF_TYPE_META_CAPTURE:
+ queue->queue.ops = &uvc_meta_queue_qops;
+ break;
+ default:
+ queue->queue.io_modes |= VB2_DMABUF;
+ queue->queue.ops = &uvc_queue_qops;
+ break;
+ }
+
ret = vb2_queue_init(&queue->queue);
if (ret)
return ret;
@@ -1120,6 +1120,82 @@ static int uvc_video_encode_data(struct uvc_streaming *stream,
}
/* ------------------------------------------------------------------------
+ * Metadata
+ */
+
+/*
+ * Additionally to the payload headers we also want to provide the user with USB
+ * Frame Numbers and system time values. The resulting buffer is thus composed
+ * of blocks, containing a 64-bit timestamp in nanoseconds, a 16-bit USB Frame
+ * Number, and a copy of the payload header.
+ *
+ * Ideally we want to capture all payload headers for each frame. However, their
+ * number is unknown and unbound. We thus drop headers that contain no vendor
+ * data and that either contain no SCR value or an SCR value identical to the
+ * previous header.
+ */
+static void uvc_video_decode_meta(struct uvc_streaming *stream,
+ struct uvc_buffer *meta_buf,
+ const u8 *mem, unsigned int length)
+{
+ struct uvc_meta_buf *meta;
+ size_t len_std = 2;
+ bool has_pts, has_scr;
+ unsigned long flags;
+ ktime_t time;
+ const u8 *scr;
+
+ if (!meta_buf || length == 2)
+ return;
+
+ if (meta_buf->length - meta_buf->bytesused <
+ length + sizeof(meta->ns) + sizeof(meta->sof)) {
+ meta_buf->error = 1;
+ return;
+ }
+
+ has_pts = mem[1] & UVC_STREAM_PTS;
+ has_scr = mem[1] & UVC_STREAM_SCR;
+
+ if (has_pts) {
+ len_std += 4;
+ scr = mem + 6;
+ } else {
+ scr = mem + 2;
+ }
+
+ if (has_scr)
+ len_std += 6;
+
+ if (stream->meta.format == V4L2_META_FMT_UVC)
+ length = len_std;
+
+ if (length == len_std && (!has_scr ||
+ !memcmp(scr, stream->clock.last_scr, 6)))
+ return;
+
+ meta = (struct uvc_meta_buf *)((u8 *)meta_buf->mem + meta_buf->bytesused);
+ local_irq_save(flags);
+ time = uvc_video_get_time();
+ meta->sof = usb_get_current_frame_number(stream->dev->udev);
+ local_irq_restore(flags);
+ __put_unaligned_cpu64(ktime_to_ns(time), &meta->ns);
+
+ if (has_scr)
+ memcpy(stream->clock.last_scr, scr, 6);
+
+ memcpy(&meta->length, mem, length);
+ meta_buf->bytesused += length + sizeof(meta->ns) + sizeof(meta->sof);
+
+ uvc_trace(UVC_TRACE_FRAME,
+ "%s(): t-sys %lluns, SOF %u, len %u, flags 0x%x, PTS %u, STC %u frame SOF %u\n",
+ __func__, time, meta->sof, meta->length, meta->flags,
+ has_pts ? *(u32 *)meta->buf : 0,
+ has_scr ? *(u32 *)scr : 0,
+ has_scr ? *(u32 *)(scr + 4) & 0x7ff : 0);
+}
+
+/* ------------------------------------------------------------------------
* URB handling
*/
@@ -1137,8 +1213,29 @@ static void uvc_video_validate_buffer(const struct uvc_streaming *stream,
/*
* Completion handler for video URBs.
*/
+
+static void uvc_video_next_buffers(struct uvc_streaming *stream,
+ struct uvc_buffer **video_buf, struct uvc_buffer **meta_buf)
+{
+ if (*meta_buf) {
+ struct vb2_v4l2_buffer *vb2_meta = &(*meta_buf)->buf;
+ const struct vb2_v4l2_buffer *vb2_video = &(*video_buf)->buf;
+
+ vb2_meta->sequence = vb2_video->sequence;
+ vb2_meta->field = vb2_video->field;
+ vb2_meta->vb2_buf.timestamp = vb2_video->vb2_buf.timestamp;
+
+ (*meta_buf)->state = UVC_BUF_STATE_READY;
+ if (!(*meta_buf)->error)
+ (*meta_buf)->error = (*video_buf)->error;
+ *meta_buf = uvc_queue_next_buffer(&stream->meta.queue,
+ *meta_buf);
+ }
+ *video_buf = uvc_queue_next_buffer(&stream->queue, *video_buf);
+}
+
static void uvc_video_decode_isoc(struct urb *urb, struct uvc_streaming *stream,
- struct uvc_buffer *buf)
+ struct uvc_buffer *buf, struct uvc_buffer *meta_buf)
{
u8 *mem;
int ret, i;
@@ -1160,14 +1257,15 @@ static void uvc_video_decode_isoc(struct urb *urb, struct uvc_streaming *stream,
urb->iso_frame_desc[i].actual_length);
if (ret == -EAGAIN) {
uvc_video_validate_buffer(stream, buf);
- buf = uvc_queue_next_buffer(&stream->queue,
- buf);
+ uvc_video_next_buffers(stream, &buf, &meta_buf);
}
} while (ret == -EAGAIN);
if (ret < 0)
continue;
+ uvc_video_decode_meta(stream, meta_buf, mem, ret);
+
/* Decode the payload data. */
uvc_video_decode_data(stream, buf, mem + ret,
urb->iso_frame_desc[i].actual_length - ret);
@@ -1178,13 +1276,13 @@ static void uvc_video_decode_isoc(struct urb *urb, struct uvc_streaming *stream,
if (buf->state == UVC_BUF_STATE_READY) {
uvc_video_validate_buffer(stream, buf);
- buf = uvc_queue_next_buffer(&stream->queue, buf);
+ uvc_video_next_buffers(stream, &buf, &meta_buf);
}
}
}
static void uvc_video_decode_bulk(struct urb *urb, struct uvc_streaming *stream,
- struct uvc_buffer *buf)
+ struct uvc_buffer *buf, struct uvc_buffer *meta_buf)
{
u8 *mem;
int len, ret;
@@ -1207,8 +1305,7 @@ static void uvc_video_decode_bulk(struct urb *urb, struct uvc_streaming *stream,
do {
ret = uvc_video_decode_start(stream, buf, mem, len);
if (ret == -EAGAIN)
- buf = uvc_queue_next_buffer(&stream->queue,
- buf);
+ uvc_video_next_buffers(stream, &buf, &meta_buf);
} while (ret == -EAGAIN);
/* If an error occurred skip the rest of the payload. */
@@ -1218,6 +1315,8 @@ static void uvc_video_decode_bulk(struct urb *urb, struct uvc_streaming *stream,
memcpy(stream->bulk.header, mem, ret);
stream->bulk.header_size = ret;
+ uvc_video_decode_meta(stream, meta_buf, mem, ret);
+
mem += ret;
len -= ret;
}
@@ -1241,7 +1340,7 @@ static void uvc_video_decode_bulk(struct urb *urb, struct uvc_streaming *stream,
uvc_video_decode_end(stream, buf, stream->bulk.header,
stream->bulk.payload_size);
if (buf->state == UVC_BUF_STATE_READY)
- uvc_queue_next_buffer(&stream->queue, buf);
+ uvc_video_next_buffers(stream, &buf, &meta_buf);
}
stream->bulk.header_size = 0;
@@ -1251,7 +1350,7 @@ static void uvc_video_decode_bulk(struct urb *urb, struct uvc_streaming *stream,
}
static void uvc_video_encode_bulk(struct urb *urb, struct uvc_streaming *stream,
- struct uvc_buffer *buf)
+ struct uvc_buffer *buf, struct uvc_buffer *meta_buf)
{
u8 *mem = urb->transfer_buffer;
int len = stream->urb_size, ret;
@@ -1297,7 +1396,10 @@ static void uvc_video_complete(struct urb *urb)
{
struct uvc_streaming *stream = urb->context;
struct uvc_video_queue *queue = &stream->queue;
+ struct uvc_video_queue *qmeta = &stream->meta.queue;
+ struct vb2_queue *vb2_qmeta = stream->meta.vdev.queue;
struct uvc_buffer *buf = NULL;
+ struct uvc_buffer *buf_meta = NULL;
unsigned long flags;
int ret;
@@ -1316,6 +1418,8 @@ static void uvc_video_complete(struct urb *urb)
case -ECONNRESET: /* usb_unlink_urb() called. */
case -ESHUTDOWN: /* The endpoint is being disabled. */
uvc_queue_cancel(queue, urb->status == -ESHUTDOWN);
+ if (vb2_qmeta)
+ uvc_queue_cancel(qmeta, urb->status == -ESHUTDOWN);
return;
}
@@ -1325,7 +1429,15 @@ static void uvc_video_complete(struct urb *urb)
queue);
spin_unlock_irqrestore(&queue->irqlock, flags);
- stream->decode(urb, stream, buf);
+ if (vb2_qmeta) {
+ spin_lock_irqsave(&qmeta->irqlock, flags);
+ if (!list_empty(&qmeta->irqqueue))
+ buf_meta = list_first_entry(&qmeta->irqqueue,
+ struct uvc_buffer, queue);
+ spin_unlock_irqrestore(&qmeta->irqlock, flags);
+ }
+
+ stream->decode(urb, stream, buf, buf_meta);
if ((ret = usb_submit_urb(urb, GFP_ATOMIC)) < 0) {
uvc_printk(KERN_ERR, "Failed to resubmit video URB (%d).\n",
@@ -478,6 +478,8 @@ struct uvc_stats_stream {
unsigned int max_sof; /* Maximum STC.SOF value */
};
+#define UVC_METATADA_BUF_SIZE 1024
+
struct uvc_streaming {
struct list_head list;
struct uvc_device *dev;
@@ -509,7 +511,13 @@ struct uvc_streaming {
unsigned int frozen : 1;
struct uvc_video_queue queue;
void (*decode) (struct urb *urb, struct uvc_streaming *video,
- struct uvc_buffer *buf);
+ struct uvc_buffer *buf, struct uvc_buffer *meta_buf);
+
+ struct {
+ struct video_device vdev;
+ struct uvc_video_queue queue;
+ __u32 format;
+ } meta;
/* Context data used by the bulk completion handler. */
struct {
@@ -551,6 +559,8 @@ struct uvc_streaming {
u16 last_sof;
u16 sof_offset;
+ u8 last_scr[6];
+
spinlock_t lock;
} clock;
};
@@ -560,6 +570,7 @@ struct uvc_device {
struct usb_interface *intf;
unsigned long warnings;
__u32 quirks;
+ __u32 meta_format;
int intfnum;
char name[32];
@@ -714,6 +725,7 @@ extern int uvc_query_ctrl(struct uvc_device *dev, __u8 query, __u8 unit,
void uvc_video_clock_update(struct uvc_streaming *stream,
struct vb2_v4l2_buffer *vbuf,
struct uvc_buffer *buf);
+int uvc_meta_register(struct uvc_streaming *stream);
int uvc_register_video_device(struct uvc_device *dev,
struct uvc_streaming *stream,
@@ -776,7 +788,7 @@ extern struct usb_host_endpoint *uvc_find_endpoint(
/* Quirks support */
void uvc_video_decode_isight(struct urb *urb, struct uvc_streaming *stream,
- struct uvc_buffer *buf);
+ struct uvc_buffer *buf, struct uvc_buffer *meta_buf);
/* debugfs and statistics */
void uvc_debugfs_init(void);
@@ -67,4 +67,30 @@ struct uvc_xu_control_query {
#define UVCIOC_CTRL_MAP _IOWR('u', 0x20, struct uvc_xu_control_mapping)
#define UVCIOC_CTRL_QUERY _IOWR('u', 0x21, struct uvc_xu_control_query)
+/*
+ * Metadata node
+ */
+
+/**
+ * struct uvc_meta_buf - metadata buffer building block
+ * @ns - system timestamp of the payload in nanoseconds
+ * @sof - USB Frame Number
+ * @length - length of the payload header
+ * @flags - payload header flags
+ * @buf - optional device-specific header data
+ *
+ * UVC metadata nodes fill buffers with possibly multiple instances of this
+ * struct. The first two fields are added by the driver, they can be used for
+ * clock synchronisation. The rest is an exact copy of a UVC payload header.
+ * Only complete objects with complete buffers are included. Therefore it's
+ * always sizeof(meta->ts) + sizeof(meta->sof) + meta->length bytes large.
+ */
+struct uvc_meta_buf {
+ __u64 ns;
+ __u16 sof;
+ __u8 length;
+ __u8 flags;
+ __u8 buf[];
+} __packed;
+
#endif